Kathryn Stevens

All Publications

• Super-resolution musculoskeletal MRI using deep learning. Magnetic resonance in medicine Chaudhari, A. S., Fang, Z., Kogan, F., Wood, J., Stevens, K. J., Gibbons, E. K., Lee, J. H., Gold, G. E., Hargreaves, B. A. 2018

  Abstract

  PURPOSE: To develop a super-resolution technique using convolutional neural networks for generating thin-slice knee MR images from thicker input slices, and compare this method with alternative through-plane interpolation methods.METHODS: We implemented a 3D convolutional neural network entitled DeepResolve to learn residual-based transformations between high-resolution thin-slice images and lower-resolution thick-slice images at the same center locations. DeepResolve was trained using 124 double echo in steady-state (DESS) data sets with 0.7-mm slice thickness and tested on 17 patients. Ground-truth images were compared with DeepResolve, clinically used tricubic interpolation, and Fourier interpolation methods, along with state-of-the-art single-image sparse-coding super-resolution. Comparisons were performed using structural similarity, peak SNR, and RMS error image quality metrics for a multitude of thin-slice downsampling factors. Two musculoskeletal radiologists ranked the 3 data sets and reviewed the diagnostic quality of the DeepResolve, tricubic interpolation, and ground-truth images for sharpness, contrast, artifacts, SNR, and overall diagnostic quality. Mann-Whitney U tests evaluated differences among the quantitative image metrics, reader scores, and rankings. Cohen's Kappa (kappa) evaluated interreader reliability.RESULTS: DeepResolve had significantly better structural similarity, peak SNR, and RMS error than tricubic interpolation, Fourier interpolation, and sparse-coding super-resolution for all downsampling factors (p<.05, except 4*and 8*sparse-coding super-resolution downsampling factors). In the reader study, DeepResolve significantly outperformed (p<.01) tricubic interpolation in all image quality categories and overall image ranking. Both readers had substantial scoring agreement (kappa=0.73).CONCLUSION: DeepResolve was capable of resolving high-resolution thin-slice knee MRI from lower-resolution thicker slices, achieving superior quantitative and qualitative diagnostic performance to both conventionally used and state-of-the-art methods.

  View details for DOI 10.1002/mrm.27178

  View details for PubMedID 29582464

• Accelerated three-dimensional multispectral MRI with robust principal component analysis for separation of on- and off-resonance signals MAGNETIC RESONANCE IN MEDICINE Levine, E., Stevens, K., Beaulieu, C., Hargreaves, B. 2018; 79 (3): 1495–1505

  Abstract

  To enable highly accelerated distortion-free MRI near metal by separating on- and off-resonance to exploit the redundancy of slice-phase encoding for the dominant on-resonance component.Multispectral MRI techniques resolve off-resonance distortions by a combination of limited excitation bins and additional encoding. Inspired by robust principal component analysis, a novel compact representation of multispectral images as a sum of rank-one and sparse matrices corresponding to on- and off-resonance respectively is described. This representation is used in a calibration-free and model-free reconstruction for data with an undersampling pattern that varies between bins. Retrospective undersampling was used to compare the proposed reconstruction and bin-by-bin compressed sensing. Hip images were acquired in eight patients with standard and prospectively undersampled three-dimensional multispectral imaging, and image quality was evaluated by two radiologists on a 5-point scale.Experiments with retrospective undersampling showed that the enhanced sparsity afforded by the separation greatly reduces reconstruction errors and artifacts. Images from prospectively undersampled multispectral imaging offered 2.6-3.4-fold (18-24-fold overall) acceleration compared to standard multispectral imaging with parallel imaging and partial-Fourier acceleration with equivalence in all qualitative assessments within a tolerance of one point (P < 0.004).Three-dimensional multispectral imaging can be highly accelerated by varying undersampling between bins and separating on- and off-resonance. Magn Reson Med 79:1495-1505, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

  View details for DOI 10.1002/mrm.26819

  View details for Web of Science ID 000427184700026

  View details for PubMedID 28686800

  View details for PubMedCentralID PMC5756705

• Musculoskeletal imaging insight 2015: Kenya SKELETAL RADIOLOGY Stevens, K. J., Mutiso, K., Sconfienza, L. M., Monu, J. 2016; 45 (7): 883-888

  Abstract

  Over the past 6 years the International Skeletal Society (ISS) outreach programs have become popular amongst the various radiology organizations in sub-Saharan Africa. So much so that that the ISS outreach is now routinely expected to participate in many of the international radiology conferences in that part of the world. The organizational planning for an outreach visit to Kenya took place over a 3-year period. Eventually a double-headed event; the seventh and eighth sub-Saharan outreach efforts were organized in Nairobi and in Mombasa, Kenya. The Nairobi outreach was an educational course on musculoskeletal imaging at the University of Nairobi and the Aga Khan University in Nairobi from 26 to 28 May 2015. The Mombasa outreach was organized in collaboration with the African Society of Radiology (ASR) at their annual meeting in Mombasa from 30 May to 2 June 2015.

  View details for DOI 10.1007/s00256-016-2391-x

  View details for Web of Science ID 000376510000001

  View details for PubMedID 27115883

• Elbow Imaging in Sport: Sports Imaging Series RADIOLOGY Bucknor, M. D., Stevens, K. J., Steinbach, L. S. 2016; 279 (1): 12-28

  Abstract

  Elbow pain is a frequent presenting symptom in athletes, particularly athletes who throw. The elbow can be injured as a result of acute trauma, such as a direct blow or a fall onto an outstretched hand or from chronic microtrauma. In particular, valgus extension overload during the throwing motion can precipitate a cascade of chronic injuries that can be debilitating for both casual and high-performance athletes. Prompt imaging evaluation facilitates accurate diagnosis and appropriate targeted interventions.

  View details for DOI 10.1148/radiol.2016150501

  View details for Web of Science ID 000378709700002

  View details for PubMedID 26989928

• MRI findings of serous atrophy of bone marrow and associated complications EUROPEAN RADIOLOGY Boutin, R. D., White, L. M., Laor, T., Spitz, D. J., Lopez-Ben, R. R., Stevens, K. J., Bredella, M. A. 2015; 25 (9): 2771-2778

  Abstract

  To report the MRI appearance of serous atrophy of bone marrow (SABM) and analyse clinical findings and complications of SABM.A retrospective search of MRI examinations of SABM was performed. Symptoms, underlying conditions, MRI findings, delay in diagnosis and associated complications were recorded.We identified 30 patients (15 male, 15 female; mean age: 46 ± 21 years) with MRI findings of SABM. Underlying conditions included anorexia nervosa (n = 10), cachexia from malignant (n = 5) and non-malignant (n = 7) causes, massive weight loss after bariatric surgery (n = 1), biliary atresia (n = 1), AIDS (n = 3), endocrine disorders (n = 2) and scurvy (n = 1). MRI showed mildly hypointense signal on T1- weighted and hyperintense signal on fat-suppressed fluid-sensitive images of affected bone marrow in all cases and similar signal abnormalities of the adjacent subcutaneous fat in 29/30 cases. Seven patients underwent repeat MRI due to initial misinterpretation of bone marrow signal as technical error. Superimposed fractures of the hips and lower extremities were common (n = 14).SABM occurs most commonly in anorexia nervosa and cachexia. MRI findings of SABM are often misinterpreted as technical error requiring unnecessary repeat imaging. SABM is frequently associated with fractures of the lower extremities.• SABM occurs in several underlying conditions, most commonly anorexia nervosa and cachexia. • Abnormal marrow signal is often misinterpreted as technical error requiring unnecessary repeat imaging. • SABM is frequently associated with stress fractures. • Fractures in SABM can be obscured by marrow signal abnormality on MRI.

  View details for DOI 10.1007/s00330-015-3692-5

  View details for Web of Science ID 000359396700031

  View details for PubMedID 25773942

• Approach to MR Imaging of the Elbow and Wrist: Technical Aspects and Innovation. Magnetic resonance imaging clinics of North America Johnson, D., Stevens, K. J., Riley, G., Shapiro, L., Yoshioka, H., Gold, G. E. 2015; 23 (3): 355-366

  View details for DOI 10.1016/j.mric.2015.04.008

  View details for PubMedID 26216768

• Femoral Neck Stress Fractures and Imaging Features of Femoroacetabular Impingement PM&R Goldin, M., Anderson, C. N., Fredericson, M., Safran, M. R., Stevens, K. J. 2015; 7 (6): 584-592

  Abstract

  Prior literature has suggested an association between the radiographic signs of femoroacetabular impingement (FAI) and femoral neck stress fractures (FNSF) or femoral neck stress reactions (FNSR). At the time of the writing of this article, no study has described the association of FAI and FNSF/FNSR along with the need for surgical intervention and outcomes.To determine the prevalence of radiographic features of FAI in patients diagnosed with FNSF.Retrospective case series.Tertiary care, institutional setting.A medical records search program (Stanford Translational Research Integrated Database Environment, Stanford University, California) was used to retrospectively search for patients 18-40 years old with a history of FNSF or FNSR. The records were obtained from the period July 25, 2003, to September 23, 2011.For assessment of risk factors, plain radiographs and magnetic resonance imaging studies were reviewed for features of cam or pincer FAI. Medical records were reviewed to determine whether patients required operative intervention.Incidence of abnormal alpha (α) angle, abnormal anterior offset ratio, abnormal femoral head-neck junction, coxa profunda, positive crossover sign, and abnormal lateral center-to-edge angle.Twenty-one female and 3 male participants (mean age 27 years, range 19-39 years) were identified with magnetic resonance imaging evidence of femoral neck stress injury. Cam morphology was seen in 10 patients (42%). Pincer morphology could be assessed in 18 patients, with coxa profunda in 14 (78%) and acetabular retroversion in 6 (14%). Features of combined pincer and cam impingement were observed in 4 patients (17%). Seven patients (29%) had operative intervention, with 3 (12%) requiring internal fixation of their femoral neck fractures, and all had radiographic evidence of fracture union after surgery. Four patients (17%) had persistent symptoms after healing of their FNSF with conservative treatment and eventually required surgery for FAI, 3 had no pain at final follow-up 1 year post-surgery, and one patient was lost to follow-up.The results of the current study suggest that patients in the general population with femoral neck stress injuries have a higher incidence of bony abnormalities associated with pincer impingement, including coxa profunda and acetabular retroversion, although it is unclear whether pincer FAI is a true risk factor in the development of FNSF.

  View details for DOI 10.1016/j.pmrj.2014.12.008

  View details for Web of Science ID 000356053400005

  View details for PubMedID 25591871

• MR Imaging Near Metallic Implants Using MAVRIC SL: Initial Clinical Experience at 3T ACADEMIC RADIOLOGY Gutierrez, L. B., Do, B. H., Gold, G. E., Hargreaves, B. A., Koch, K. M., Worters, P. W., Stevens, K. J. 2015; 22 (3): 370-379

  Abstract

  To compare the effectiveness of multiacquisition with variable resonance image combination selective (MAVRIC SL) with conventional two-dimensional fast spin-echo (2D-FSE) magnetic resonance (MR) techniques at 3T in imaging patients with a variety of metallic implants.Twenty-one 3T MR studies were obtained in 19 patients with different types of metal implants. Paired MAVRIC SL and 2D-FSE sequences were reviewed by two radiologists and compared for in-plane and through-plane metal artifact, visualization of the bone implant interface and surrounding soft tissues, blurring, and overall image quality using a two-tailed Wilcoxon signed rank test. The area of artifact on paired images was measured and compared using a paired Wilcoxon signed rank test. Changes in patient management resulting from MAVRIC SL imaging were documented.Significantly less in-plane and through-plane artifact was seen with MAVRIC SL, with improved visualization of the bone-implant interface and surrounding soft tissues, and superior overall image quality (P = .0001). Increased blurring was seen with MAVRIC SL (P = .0016). MAVRIC SL significantly decreased the image artifact compared to 2D-FSE (P = .0001). Inclusion of MAVRIC SL to the imaging protocol determined the need for surgery or type of surgery in five patients and ruled out the need for surgery in 13 patients. In three patients, the area of interest was well seen on both MAVRIC SL and 2D-FSE images, so the addition of MAVRIC had no effect on patient management.Imaging around metal implants with MAVRIC SL at 3T significantly improved image quality and decreased image artifact compared to conventional 2D-FSE imaging techniques and directly impacted patient management.

  View details for DOI 10.1016/j.acra.2014.09.010

  View details for Web of Science ID 000349659300014

  View details for PubMedID 25435186

• MRI of the Hip for the evaluation of femoroacetabular impingement; past, present, and future. Journal of magnetic resonance imaging : JMRI Riley, G. M., McWalter, E. J., Stevens, K. J., Safran, M. R., Lattanzi, R., Gold, G. E. 2015; 41 (3): 558-572

  Abstract

  The concept of femoroacetabular impingement (FAI) has, in a relatively short time, come to the forefront of orthopedic imaging. In just a few short years MRI findings that were in the past ascribed to degenerative change, normal variation, or other pathologies must now be described and included in radiology reports, as they have been shown, or are suspected to be related to, FAI. Crucial questions have come up in this time, including: what is the relationship of bony morphology to subsequent cartilage and labral damage, and most importantly, how is this morphology related to the development of osteoarthritis? In this review, we attempt to place a historical perspective on the controversy, provide guidelines for interpretation of MRI examinations of patients with suspected FAI, and offer a glimpse into the future of MRI of this complex condition. J. Magn. Reson. Imaging 2014. © 2014 Wiley Periodicals, Inc.

  View details for DOI 10.1002/jmri.24725

  View details for PubMedID 25155435

• Validation of a Novel Radiographic Scoring System for Calcinosis Affecting the Hands of Patients With Systemic Sclerosis ARTHRITIS CARE & RESEARCH Chung, L., Valenzuela, A., Fiorentino, D., Stevens, K., Li, S., Harris, J., Hutchinson, C., Assassi, S., Beretta, L., Lakshminarayanan, S., Rodriguez-Reyna, T. S., Denton, C. P., Taillefer, R. G., Herrick, A. L., Baron, M. 2015; 67 (3): 425-430

  Abstract

  Objective: There are currently no validated outcome measures to assess calcinosis severity in systemic sclerosis (SSc). We sought to develop and validate a novel radiographic scoring system for calcinosis affecting the hands of SSc patients for potential use in future clinical trials. Methods: Following a 1-hour teleconference training session, 12 investigators (8 rheumatologists, 1 dermatologist, 3 radiologists) scored 12 hand radiographs in random order using two scoring systems (termed "simple" and "complex"), and re-scored 2 randomly assigned radiographs after a minimum of 24 hours. Inter-rater and intra-rater reliability were assessed using a weighted kappa coefficient for the simple system, and intraclass correlation coefficient (ICC) for the complex system (ICC < 0.4 poor, 0.4-0.7 moderate, > 0.7 excellent). Results: Mean time to complete the complex scoring system was significantly longer than the simple scoring system (4.0 vs. 0.4 minutes, p<.0001). Overall inter-rater reliability for the simple scoring system was poor (kappa=0.39, 95% CI 0.1-0.52), but improved if dichotomized as mild/moderate vs. severe (kappa=0.51, 95% CI 0.26-0.7). Inter-rater reliability was excellent for the complex scoring system (ICC=0.89, 95% CI 0.86-0.92). Intra-rater reliability was moderate for the simple scoring system (kappa=0.67, 95% CI 0.37-0.96), but almost perfect for the complex scoring system (ICC=0.93, 95%CI 0.89-0.97). Conclusion: We developed a novel radiographic scoring system that accounts for the area coverage, density, and anatomic location of calcinosis affecting the hands in patients with SSc. This scoring system is feasible with excellent reliability and should undergo further validation testing for use in clinical trials. © 2014 American College of Rheumatology.

  View details for DOI 10.1002/acr.22434

  View details for Web of Science ID 000350295500015

  View details for PubMedID 25155948

• Metal Artifact Reduction With MAVRIC SL at 3-T MRI in Patients With Hip Arthroplasty AMERICAN JOURNAL OF ROENTGENOLOGY Choi, S., Koch, K. M., Hargreaves, B. A., Stevens, K. J., Gold, G. E. 2015; 204 (1): 140-147

  Abstract

  The objective of our study was to compare the multiacquisition variable-resonance image combination selective (MAVRIC SL) sequence with the 2D fast spin-echo (FSE) sequence for metal artifact reduction on 3-T MRI in patients with hip arthroplasty (HA).Matched 2D FSE and MAVRIC SL images of 21 hips (19 patients with HA) were included in the study group. Paired image sets, composed of 13 coronal and 12 axial slices (total, 25 image sets), of the 21 hips were evaluated. For quantitative analysis, the artifact area was measured at the level of the hip and femur. For qualitative analysis, two musculoskeletal radiologists independently compared paired 2D FSE and MAVRIC SL sets in terms of artifacts, depiction of anatomic detail, level of diagnostic confidence, and detection of abnormal findings.The measured artifact area was significantly smaller (p < 0.05) on MAVRIC SL than 2D FSE at both the level of hip (59.9% reduction with MAVRIC SL) and femur (31.3% reduction with MAVRIC SL). The artifact score was also significantly decreased (p < 0.0001) with MAVRIC SL compared with 2D FSE for both reviewers. The hip joint capsule and the muscle and tendon attachment sites of the obturator externus and iliopsoas muscles were better depicted with MAVRIC SL than 2D FSE (p < 0.0125). Abnormal findings were significantly better shown on MAVRIC SL imaging compared with 2D FSE imaging (p < 0.0001).The MAVRIC SL sequence can significantly reduce metal artifact on 3-T MRI compared with the 2D FSE sequence and can increase diagnostic confidence of 3-T MRI in patients with total HA.

  View details for DOI 10.2214/AJR.13.11785

  View details for Web of Science ID 000348562300044

  View details for PubMedID 25539249

• Ultrasound-guided musculoskeletal interventions in American football: 18 years of experience. AJR. American journal of roentgenology Dave, R. B., Stevens, K. J., Shivaram, G. M., McAdams, T. R., Dillingham, M. F., Beaulieu, C. F. 2014; 203 (6): W674-83

  Abstract

  Myotendinous strains, contusions, and hematomas are common injuries in American football. Along with ligament sprains and inflammatory disorders, musculoskeletal injuries often result in lost participation time. This article summarizes 18 years of experience with 128 ultrasound-guided drainages and injections in 69 football players with 88 injuries.When performed by an operator with sufficient expertise in diagnostic and procedural skills, ultrasound-guided musculoskeletal interventions are minimally invasive, are safe, and can play an integral role in injury management.

  View details for DOI 10.2214/AJR.14.12678

  View details for PubMedID 25415734

• Late-onset en coup de sabre of the skull. Skeletal radiology Mohan, S. V., Nittur, V., Stevens, K. J. 2013; 42 (10): 1447-1450

  Abstract

  En coup de sabre is a rare subtype of linear scleroderma that characteristically affects the skin, underlying muscle, and bone of the frontoparietal region of the face and scalp. It typically presents in the first two decades of life, and may be associated with focal neurological deficits. We present a case of late-onset en coup de sabre of the frontal bone where the diagnosis was further complicated by a history of breast cancer, prior trauma to the region, and use of topical medication.

  View details for DOI 10.1007/s00256-013-1617-4

  View details for PubMedID 23615776

• Preface. Radiologic clinics of North America Stevens, K. J. 2013; 51 (3): xi-xii

  View details for DOI 10.1016/j.rcl.2013.03.001

  View details for PubMedID 23622098

• Femoroacetabular Impingement RADIOLOGIC CLINICS OF NORTH AMERICA Dimmick, S., Stevens, K. J., Brazier, D., Anderson, S. E. 2013; 51 (3): 337-?

  Abstract

  Femoroacetabular impingement (FAI) of the hip is a well-recognized entity that can cause hip pain and limit range of motion. Although there are 2 types of FAI (cam and pincer), these 2 entities most commonly coexist. Plain radiographs and magnetic resonance imaging are commonly used to assess FAI, and play an integral role in diagnosis in conjunction with patient symptoms and clinical examination. Treatment of FAI is also evolving, with arthroscopic management becoming increasingly more popular. This review provides an overview of the proposed etiology, mechanisms, clinical history, imaging, and treatment of FAI.

  View details for DOI 10.1016/j.rcl.2012.12.002

  View details for Web of Science ID 000319085300002

  View details for PubMedID 23622088

• Imaging of Cysts and Bursae About the Knee RADIOLOGIC CLINICS OF NORTH AMERICA Steinbach, L. S., Stevens, K. J. 2013; 51 (3): 433-?

  Abstract

  Cystic lesions are common around the knee and are often encountered as an incidental finding on routine magnetic resonance imaging examinations. The clinical presentation of cysts and other fluid collections is variable, depending on their size, location, and relationship to adjacent anatomic structures. This article reviews the anatomy, etiology, clinical presentation, and imaging features of commonly occurring cystic lesions around the knee and discusses some of the potential pitfalls that may be encountered in clinical practice.

  View details for DOI 10.1016/j.rcl.2012.10.005

  View details for Web of Science ID 000319085300007

  View details for PubMedID 23622093

• Compressed-Sensing multispectral imaging of the postoperative spine JOURNAL OF MAGNETIC RESONANCE IMAGING Worters, P. W., Sung, K., Stevens, K. J., Koch, K. M., Hargreaves, B. A. 2013; 37 (1): 243-248

  Abstract

  To apply compressed sensing (CS) to in vivo multispectral imaging (MSI), which uses additional encoding to avoid magnetic resonance imaging (MRI) artifacts near metal, and demonstrate the feasibility of CS-MSI in postoperative spinal imaging.Thirteen subjects referred for spinal MRI were examined using T2-weighted MSI. A CS undersampling factor was first determined using a structural similarity index as a metric for image quality. Next, these fully sampled datasets were retrospectively undersampled using a variable-density random sampling scheme and reconstructed using an iterative soft-thresholding method. The fully and undersampled images were compared using a 5-point scale. Prospectively undersampled CS-MSI data were also acquired from two subjects to ensure that the prospective random sampling did not affect the image quality.A two-fold outer reduction factor was deemed feasible for the spinal datasets. CS-MSI images were shown to be equivalent or better than the original MSI images in all categories: nerve visualization: P = 0.00018; image artifact: P = 0.00031; image quality: P = 0.0030. No alteration of image quality and T2 contrast was observed from prospectively undersampled CS-MSI.This study shows that the inherently sparse nature of MSI data allows modest undersampling followed by CS reconstruction with no loss of diagnostic quality.

  View details for DOI 10.1002/jmri.23750

  View details for Web of Science ID 000312720000028

  View details for PubMedID 22791572

• The Biceps Muscle from Shoulder to Elbow SEMINARS IN MUSCULOSKELETAL RADIOLOGY Stevens, K., Kwak, A., Poplawski, S. 2012; 16 (4): 296-315

  Abstract

  The biceps brachii plays an integral role in movement of the shoulder and elbow, and pathology can occur in athletes of all ages. Injuries of the proximal biceps tendon can be seen in overhead athletes as a result of chronic impingement, tendon instability, or tensile overload, often with accompanying lesions of the labrum or rotator cuff. Presentation may be insidious or can be precipitated by an acute event. Injuries to the distal biceps are more common in athletes involved in strength training such as weightlifters, or occasionally in contact sports. Although injury to the proximal and distal biceps can often be diagnosed clinically, MRI is an excellent imaging modality to evaluate the extent of disease and involvement of adjacent structures. This article reviews the anatomy of the biceps brachii from the shoulder to elbow and discusses commonly occurring pathology of the biceps and adjacent anatomical structures.

  View details for DOI 10.1055/s-0032-1327004

  View details for Web of Science ID 000309850500005

  View details for PubMedID 23047278

• Fluoroscopically Guided Supraglenoid Tubercle Steroid Injections for the Management of Biceps Tendonitis PAIN PRACTICE Mitra, R., Nguyen, A., Stevens, K. J. 2011; 11 (4): 392-396

  Abstract

  The management of bicipital tendonitis can be challenging to the clinician. Traditionally, blind injections near the bicipital groove have been performed by clinicians with risk of bicipital tendon rupture or atrophy. Because of the inaccuracy and risk associated with blind bicipital tendon steroid injections, we sought to ascertain whether a fluoroscopically guided steroid injection into the region of the origin of the long head of the bicipital tendon (supraglenoid tubercle) was efficacious.A retrospective chart review of 6 consecutive patients with a diagnosis of bicipital tendonitis was performed. All patients underwent a fluoroscopically guided steroid/anesthetic injection into the supraglenoid tubercle of the shoulder. The main outcome measure was post-procedure change in visual analog pain scale; the secondary outcome was the physical examination (presence of a Speed's test).Ten cases were identified, but only 6 had complete data and were included in the analysis. Five of the 6 patients experienced a reduction in pain by 50% at follow-up.A fluoroscopically guided block injected into the supraglenoid tubercle may be effective in the management of bicipital tendonitis.

  View details for DOI 10.1111/j.1533-2500.2010.00424.x

  View details for Web of Science ID 000296467400009

  View details for PubMedID 21114615

• Imaging of the Wrist at 1.5 Tesla Using Isotropic Three-Dimensional Fast Spin Echo Cube JOURNAL OF MAGNETIC RESONANCE IMAGING Stevens, K. J., Wallace, C. G., Chen, W., Rosenberg, J. K., Gold, G. E. 2011; 33 (4): 908-915

  Abstract

  To compare three-dimensional fast spin echo Cube (3D-FSE-Cube) with conventional 2D-FSE in MR imaging of the wrist.The wrists of 10 volunteers were imaged in a 1.5 Tesla MRI scanner using an eight-channel wrist coil. The 3D-FSE-Cube images were acquired in the coronal plane with 0.5-mm isotropic resolution. The 2D-FSE images were acquired in both coronal and axial planes for comparison. An ROI was placed in fluid, cartilage, and muscle for SNR analysis. Comparable coronal and axial images were selected for each sequence, and paired images were randomized and graded for blurring, artifact, anatomic details, and overall image quality by three blinded musculoskeletal radiologists.SNR of fluid, cartilage and muscle at prescribed locations were higher using 3D-FSE-Cube, without reaching statistical significance. Fluid-cartilage CNR was also higher with 3D-FSE-Cube, but not statistically significant. Blurring, artifact, anatomic details, and overall image quality were significantly better on coronal 3D-FSE-Cube images (P < 0.001), but significantly better on axial 2D-FSE images compared with axial 3D-FSE-Cube reformats (P < 0.01).Isotropic data from 3D-FSE-Cube allows reformations in arbitrary scan planes, which may make multiple 2D acquisitions unnecessary, and improve depiction of complex wrist anatomy. However, axial reformations suffer from blurring, likely due to T2 decay during the long echo train, limiting overall image quality in this plane.

  View details for DOI 10.1002/jmri.22494

  View details for Web of Science ID 000288913200019

  View details for PubMedID 21448957

• Athletic Osteitis Pubis SPORTS MEDICINE Hiti, C. J., Stevens, K. J., Jamati, M. K., Garza, D., Matheson, G. O. 2011; 41 (5): 361-376

  Abstract

  Athletic osteitis pubis is a painful and chronic condition affecting the pubic symphysis and/or parasymphyseal bone that develops after athletic activity. Athletes with osteitis pubis commonly present with anterior and medial groin pain and, in some cases, may have pain centred directly over the pubic symphysis. Pain may also be felt in the adductor region, lower abdominal muscles, perineal region, inguinal region or scrotum. The pain is usually aggravated by running, cutting, hip adduction and flexion against resistance, and loading of the rectus abdominis. The pain can progress such that athletes are unable to sustain athletic activity at high levels. It is postulated that osteitis pubis is an overuse injury caused by biomechanical overloading of the pubic symphysis and adjacent parasymphyseal bone with subsequent bony stress reaction. The differential diagnosis for osteitis pubis is extensive and includes many other syndromes resulting in groin pain. Imaging, particularly in the form of MRI, may be helpful in making the diagnosis. Treatment is variable, but typically begins with conservative measures and may include injections and/or surgical procedures. Prolotherapy injections of dextrose, anti-inflammatory corticosteroids and a variety of surgical procedures have been reported in the literature with varying efficacies. Future studies of athletic osteitis pubis should attempt to define specific and reliable criteria to make the diagnosis of athletic osteitis pubis, empirically define standards of care and reduce the variability of proposed treatment regimens.

  View details for Web of Science ID 000290741000002

  View details for PubMedID 21510714

• High Hamstring Tendinopathy: MRI and Ultrasound Imaging and Therapeutic Efficacy of Percutaneous Corticosteroid Injection AMERICAN JOURNAL OF ROENTGENOLOGY Zissen, M. H., Wallace, G., Stevens, K. J., Fredericson, M., Beaulieu, C. F. 2010; 195 (4): 993-998

  Abstract

  The goals of this study were to review the MRI and sonographic findings in patients diagnosed clinically with high hamstring tendinopathy and to evaluate the efficacy of ultrasound-guided corticosteroid injections in providing symptomatic relief.MRI is more sensitive than ultrasound in detecting peritendinous edema and tendinopathy at the proximal hamstring origin. Fifty percent of patients had symptomatic improvement lasting longer than 1 month after percutaneous corticosteroid injection, and 24% of patients had symptom relief for more than 6 months.

  View details for DOI 10.2214/AJR.09.3674

  View details for Web of Science ID 000282033600030

  View details for PubMedID 20858830

• Magnetic Resonance Imaging of the Elbow in Athletes CLINICS IN SPORTS MEDICINE Stevens, K. J., McNally, E. G. 2010; 29 (4): 521-?

  Abstract

  Acute and chronic elbow pain is common, particularly in athletes. Although plain radiographs, ultrasound, and computed tomography all have a role to play in the investigation of elbow pain, magnetic resonance imaging (MRI) has emerged as the imaging modality of choice for diagnosis of soft tissue disease and osteochondral injury around the elbow. The high spatial resolution, excellent soft-tissue contrast, and multiplanar imaging capabilities of MRI make it ideal for evaluating the complex joint anatomy of the elbow. This article reviews imaging of common disease conditions occurring around the elbow in athletes, with an emphasis on MRI.

  View details for DOI 10.1016/j.csm.2010.06.004

  View details for Web of Science ID 000283562000003

  View details for PubMedID 20883896

• Magnetic Resonance Imaging of the Elbow JOURNAL OF MAGNETIC RESONANCE IMAGING Stevens, K. J. 2010; 31 (5): 1036-1053

  Abstract

  Elbow pain is frequently encountered in clinical practice and can result in significant morbidity, particularly in athletes. Magnetic resonance imaging (MRI) is an excellent diagnostic imaging tool for the evaluation of soft tissue and osteochondral pathology around the elbow. Recent advances in magnetic field strength and coil design have lead to improved spatial resolution and superior soft tissue contrast, making it ideal for visualization of complex joint anatomy. This article describes the normal imaging appearances of anatomy around the elbow and reviews commonly occurring ligamentous, myotendinous, neural, and bursal pathology around the elbow.

  View details for DOI 10.1002/jmri.22154

  View details for Web of Science ID 000277397100001

  View details for PubMedID 20432337

• Imaging and Ultrasound-Guided Steroid Injection of Internal Oblique Muscle Strains in Baseball Pitchers AMERICAN JOURNAL OF SPORTS MEDICINE Stevens, K. J., Crain, J. M., Akizuki, K. H., Beaulieu, C. F. 2010; 38 (3): 581-585

  Abstract

  Internal oblique muscle injuries are common in professional baseball pitchers and may require a prolonged convalescence of up to 10 weeks. Most strains can be diagnosed clinically, but imaging can be helpful to assess the severity of injury, which may predict recovery and return to play.Ultrasound-guided injection of steroid and local anesthetic into the muscle tear can speed recovery and subsequent return to play.Case series; Level of evidence, 4.Three professional baseball pitchers with acute tears of the internal oblique muscle confirmed by magnetic resonance imaging underwent ultrasound-guided injection of steroid and local anesthetic.All 3 patients experienced significant pain relief within a few days of the injection and were able to pitch at full speed within 3 weeks of injury (mean, 21 days) and return to able status by 5 weeks (mean, 30.7 days). The 3 athletes continue to pitch in Major League Baseball 36 months, 36 months, and 14 months, respectively, after injury, and none have sustained reinjury during this time.Therapeutic injection of steroids and anesthetic under ultrasound guidance appears to speed recovery and rehabilitation in professional baseball pitchers with acute side strains.

  View details for DOI 10.1177/0363546509350105

  View details for Web of Science ID 000274803800021

  View details for PubMedID 20051499

• Dynamic Ultrasound to Diagnose Subluxating Biceps Femoris Tendon over the Fibular Head: A Case Report PM&R Huang, L., Stevens, K. J., Fredericson, M. 2009; 1 (7): 681-683

  View details for DOI 10.1016/j.pmrj.2009.02.009

  View details for Web of Science ID 000208411700011

• Ankle: Isotropic MR Imaging with 3D-FSE-Cube-Initial Experience in Healthy Volunteers RADIOLOGY Stevens, K. J., Busse, R. F., Han, E., Brau, A. C., Beatty, P. J., Beaulieu, C. F., Gold, G. E. 2008; 249 (3): 1026-1033

  Abstract

  The purpose of this prospective study was to compare a new isotropic three-dimensional (3D) fast spin-echo (FSE) pulse sequence with parallel imaging and extended echo train acquisition (3D-FSE-Cube) with a conventional two-dimensional (2D) FSE sequence for magnetic resonance (MR) imaging of the ankle. After institutional review board approval and informed consent were obtained and in accordance with HIPAA privacy guidelines, MR imaging was performed in the ankles of 10 healthy volunteers (four men, six women; age range, 25-41 years). Imaging with the 3D-FSE-Cube sequence was performed at 3.0 T by using both one-dimensional- and 2D-accelerated autocalibrated parallel imaging to decrease imaging time. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) with 3D-FSE-Cube were compared with those of the standard 2D FSE sequence. Cartilage, muscle, and fluid SNRs were significantly higher with the 3D-FSE-Cube sequence (P < .01 for all). Fluid-cartilage CNR was similar for both techniques. The two sequences were also compared for overall image quality, blurring, and artifacts. No significant difference for overall image quality and artifacts was demonstrated between the 2D FSE and 3D-FSE-Cube sequences, although the section thickness in 3D-FSE-Cube imaging was much thinner (0.6 mm). However, blurring was significantly greater on the 3D-FSE-Cube images (P < .04). The 3D-FSE-Cube sequence with isotropic resolution is a promising new MR imaging sequence for viewing complex joint anatomy.

  View details for DOI 10.1148/radiol.2493080227

  View details for Web of Science ID 000261139300036

  View details for PubMedID 19011194

• Discordance rates between preliminary and final radiology reports on cross-sectional imaging studies at a level 1 trauma center ACADEMIC RADIOLOGY Stevens, K. J., Griffiths, K. L., Rosenberg, J., Mahadevan, S., Zatz, L. M., Leung, A. N. 2008; 15 (10): 1217-1226

  Abstract

  The goal was to determine discordance rates between preliminary radiology reports provided by on-call radiology house staff and final reports from attending radiologists on cross-sectional imaging studies requested by emergency department staff after hours.A triplicate carbon copy reporting form was developed to provide permanent records of preliminary radiology reports and to facilitate communication of discrepant results to the emergency department. Data were collected over 21 weeks to determine the number of discordant readings. Patients' medical records were reviewed to show whether discrepancies were significant or insignificant and to assess their impact on subsequent management and patient outcome.The emergency department requested 2830 cross-sectional imaging studies after hours and 2311 (82%) had a copy of the triplicate form stored in radiology archives. Discrepancies between the preliminary and final report were recorded in 47 (2.0%), with 37 (1.6%) considered significant: 14 patients needed no change, 13 needed a minor change, and 10 needed a major change in subsequent management. Ten (0.43%) of the discordant scans were considered insignificant. A random sample of 104 (20%) of the 519 scans without a paper triplicate form was examined. Seventy-one (68%) did have a scanned copy of the triplicate form in the electronic record, with a discrepancy recorded in 3 (4.2%), which was not statistically different from the main cohort (P = .18).Our study suggests a high level of concordance between preliminary reports from on-call radiology house staff and final reports by attending subspecialty radiologists on cross-sectional imaging studies requested by the emergency department.

  View details for DOI 10.1016/j.acra.2008.03.017

  View details for Web of Science ID 000259742400002

  View details for PubMedID 18790392

• Tibial aperture bone disruption after retrograde versus antegrade tibial tunnel drilling: a cadaveric study KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY McAdams, T. R., Biswal, S., Stevens, K. J., Beaulieu, C. F., Mandelbaum, B. R. 2008; 16 (9): 818-822

  Abstract

  The purpose of this study is to compare the local microfracture effects of antegrade versus retrograde drilling of the tibial tunnel in ACL reconstruction. Arthroscopic ACL excision was performed on eight matched cadaveric knees. Arthroscopic guided tibial tunnel reaming was performed in either an antegrade (four) or retrograde (four) direction. A 3 x 3 cm section of proximal tibial surrounding the tibial aperture was removed with open dissection, and each section underwent micro-computed tomography analysis. Three musculoskeletal radiologists graded the specimens for bone aperture disruption and discrete fracture lines. Tibial aperture irregularity was seen in all four of the antegrade specimens (mean, Grade 1.5), and in none of the retrograde specimens. Discrete fracture lines were present in all four antegrade specimens (mean 10.13 mm depth; 8.95 mm length). No fracture lines were seen in the retrograde group. Retrograde drilling of the tibial tunnel in ACL reconstruction results in less microfracture trauma to the surrounding aperture bone. The use of retrograde drilling in ACL reconstruction may decrease synovialization of the graft-tissue interface when compared to antegrade drilling.

  View details for DOI 10.1007/s00167-008-0554-6

  View details for Web of Science ID 000258718100004

  View details for PubMedID 18516594

• Reduction of truncation artifacts in rapid 3D articular cartilage imaging JOURNAL OF MAGNETIC RESONANCE IMAGING Rakow-Penner, R., Gold, G., Daniel, B., Stevens, K., Rosenberg, J., Mazin, S. 2008; 27 (4): 860-865

  Abstract

  To reduce Gibbs ringing artifact in three-dimensional (3D) articular knee cartilage imaging with linear prediction (LP).A reconstruction method using LP in 3D was applied to truncated data sets of six healthy knees. The technique first linearizes the data before applying the prediction algorithm. Three radiologists blindly reviewed and ranked images of the full, truncated, and predicted data sets. Statistical analysis of the radiologists' reviews was performed for image quality, clinical acceptability of the images, and equivalence with the gold standard.LP applied to 3D knee cartilage imaging allows for 40% decreased scan time while providing image quality with statistical equivalence to a full data set.3D spoiled gradient echo imaging (SPGR) knee cartilage imaging requires significant scan time. This 40% reduction in scan time will allow such scans to be more feasible without sacrificing clinical acceptability.

  View details for DOI 10.1002/jmri.21312

  View details for Web of Science ID 000254709500024

  View details for PubMedID 18383247

• Introduction to diagnostic musculoskeletal ultrasound - Part 2: Examination of the lower limb AMERICAN JOURNAL OF PHYSICAL MEDICINE & REHABILITATION Chew, K., Stevens, K. J., Wang, T., Fredericson, M., Lew, H. L. 2008; 87 (3): 238-248

  Abstract

  This is the second of two articles focusing on ultrasound examination of musculoskeletal components of the upper and lower limbs. Treatment of musculoskeletal injuries is based on establishing an accurate diagnosis. No one would dispute that a good history and physical examination by a competent clinician can help achieve that in the majority of cases. However, musculoskeletal imaging is also an essential adjunct in the work-up of many musculoskeletal disorders. This article describes the ultrasound examination of the lower limb in terms of anatomic structure. Normal and pathologic ultrasound features of these structures, including muscles, tendons, ligaments, bursae, and other soft tissues of the lower limb, will be described by reviewing several representative pathologies commonly seen in musculoskeletal medicine.

  View details for DOI 10.1097/PHM.0b013e31816198c2

  View details for Web of Science ID 000253342200012

  View details for PubMedID 18174843

• VEGF and osteosclerosis in POEMS syndrome Annal of Hematology Gutgemann I, Stevens K, Loftus D, Schmidt-Wolf IGH, George TI 2008; 87: 87
• Temporal progression of skeletal cystic angiomatosis SKELETAL RADIOLOGY Shivaram, G. M., Pai, R. K., Ireland, K. B., Stevens, K. J. 2007; 36 (12): 1199-1204

  Abstract

  Cystic angiomatosis is a rare, benign, multifocal disorder of bone and viscera, in which angiomatous deposits of both vascular and lymphatic elements result in bone lysis and organ dysfunction. We report on a case of late-onset cystic angiomatosis in a Caucasian woman who first presented at age 35 years with a lytic expansile lesion of the proximal humerus, initially diagnosed as low-grade hemangio-endothelioma. This was treated with injection of cement and prophylactic pinning. However, the lesion continued to grow, and, 5 years later, she was discovered to have disseminated bony involvement, initially thought to represent metastatic disease. However, further investigation revealed a diagnosis of cystic angiomatosis, and the patient was treated with bisphosphonates. Follow-up over a 15-year period since her initial presentation at age 35 years has shown osteosclerotic conversion of many of the lesions, with development of numerous pathologic stress fractures that have failed to heal, despite operative intervention.

  View details for DOI 10.1007/s00256-007-0378-3

  View details for Web of Science ID 000250443800015

  View details for PubMedID 17912518

• Utility of Judet views in pre-operative assessment of acetabular osteolysis American Journal of Orthopedics Thomas AJ, Stevens K, Goodman SB 2007; 36 (7): 107 - 108
• Anterior cruciate ligament tears and associated injuries. Topics in magnetic resonance imaging Stevens, K. J., Dragoo, J. L. 2006; 17 (5): 347-362

  Abstract

  Anterior cruciate ligament (ACL) tears are a commonly sustained sports injury, often occurring in association with meniscal tears and trauma to other ligamentous structures around the knee. Diagnosis can often be made clinically, but assessment may be difficult in the acute setting when there is a large joint effusion and severe pain. Plain radiographs may detect the presence of a joint effusion and any associated fractures. However, magnetic resonance imaging is vital for assessing acute knee injuries and plays an important role in deciding treatment options and planning surgical intervention. Some of the associated meniscal and ligamentous injuries can be subtle and may easily be overlooked if these structures are not scrutinized closely. This article will discuss the anatomy of the ACL and the mechanisms and initial clinical assessment of ACL injuries, and review the imaging features of ACL tears and some of the associated injuries, including the posterolateral corner structures. These associated injuries have important implications for determining treatment options and subsequent return to athletic activities.

  View details for PubMedID 17414996

• Advanced magnetic resonance imaging of articular cartilage ORTHOPEDIC CLINICS OF NORTH AMERICA Gold, G. E., Hargreaves, B. A., Stevens, K. J., Beaulieu, C. F. 2006; 37 (3): 331-?

  Abstract

  MRI is one of the most accurate imaging methods available to diagnose disorders of articular cartilage. Conventional two-dimensional and three-dimensional approaches show changes in cartilage morphology. Newer and substantially faster three-dimensional imaging methods show great promise to improve MRI of cartilage. These methods may allow acquisition of fluid-sensitive isotropic data that can be reformatted into arbitrary planes for improved detection and visualization of pathology. Unique MRI contrast mechanisms also allow clinicians to probe cartilage physiology and detect early changes in cartilage macromolecules.

  View details for DOI 10.1016/j.ocl.2006.04.006

  View details for Web of Science ID 000239903400007

  View details for PubMedID 16846765

• Comparison of minimally invasive and conventional open posterolateral lumbar fusion using magnetic resonance imaging and retraction pressure studies JOURNAL OF SPINAL DISORDERS & TECHNIQUES Stevens, K. J., Spenciner, D. B., Griffiths, K. L., Kim, K. D., Zivienenberg-Lee, M., Alamin, T., Bammer, R. 2006; 19 (2): 77-86

  Abstract

  To determine whether minimally invasive lumbar spinal fusion results in less paraspinal muscle damage than conventional open posterior fusion.The maximum intramuscular pressure (IMP) generated by a minimally invasive and standard open retractor was compared in cadavers using an ultra-miniature pressure transducer. In a second clinical study, eight patients with either minimally invasive or open posterolateral lumbar spinal fusion underwent magnetic resonance imaging (MRI) scanning approximately 6 months post surgery. MRI was used to estimate edema and atrophy within multifidus, with T2 mapping and diffusion-weighted imaging allowing quantification of differences between the two surgical techniques.IMP measured with the minimally invasive retractor was 1.4 versus 4.7 kPa with the open retractor (P < 0.001). The minimally invasive retractor produced a transient maximal IMP only on initial expansion. Maximum IMP was constant throughout open retractor deployment. Striking visual differences in muscle edema were seen between open and minimally invasive groups on MRI. The mean T2 relaxation time at the level of fusion was 47 milliseconds in the minimally invasive and 90 milliseconds in the open group (P = 0.013). The mean apparent diffusion coefficient was 1357 x 10(-6) mm/s and 1626 x 10(-6) mm(2)/s (P = 0.0184), respectively.The peak IMP generated by the minimally invasive retractor was significantly less than with the open retractor. Postoperatively, less muscle edema was demonstrated after the minimally invasive lumbar spinal fusion, with lower mean T2 and apparent diffusion coefficient measurements supporting the hypothesis that less damage occurs using a minimally invasive approach.

  View details for Web of Science ID 000237437600001

  View details for PubMedID 16760779

• Sunburst periosteal reaction in osteogenic sarcoma PEDIATRIC RADIOLOGY Gross, M., Stevens, K. 2005; 35 (6): 647-648

  View details for DOI 10.1007/s00247-005-1442-6

  View details for Web of Science ID 000229106800016

  View details for PubMedID 15812635

• Driven equilibrium magnetic resonance imaging of articular cartilage: Initial clinical experience JOURNAL OF MAGNETIC RESONANCE IMAGING Gold, G. E., Fuller, S. E., Hargreaves, B. A., Stevens, K. J., Beaulieu, C. F. 2005; 21 (4): 476-481

  Abstract

  To evaluate three-dimensional driven equilibrium Fourier transform (3D-DEFT) for image quality and detection of articular cartilage lesions in the knee.We imaged 104 consecutive patients with knee pain with 3D-DEFT and proton density (PD-FSE) and T2-weighted (T2-FSE) fast spin echo. Twenty-four went on to arthroscopy. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) efficiency were measured. Subjective image quality, fat suppression, and cartilage thickness visibility were assessed. Cartilage lesions on 3D-DEFT and T2-FSE were compared with findings outlined in operative reports.SNR efficiency was higher for 3D-DEFT and PD-FSE than for T2-FSE (P < 0.02). 3D-DEFT and PD-FSE showed superior cartilage thickness visibility compared with T2-FSE (P < 0.02). T2-FSE showed better fat suppression and fewer image artifacts than 3D-DEFT (P < 0.04). 3D-DEFT had similar sensitivity and similar specificity for cartilage lesions compared with PD-FSE and T2-FSE.3D-DEFT provides excellent synovial fluid-to-cartilage contrast while preserving signal from cartilage, giving this method a high cartilage SNR. 3D-DEFT shows the full cartilage thickness better than T2-FSE. T2-FSE had superior fat saturation and fewer artifacts than 3D-DEFT. Overall, 3D-DEFT requires further technical development, but is a promising method for imaging articular cartilage.

  View details for DOI 10.1002/jhmi.20276

  View details for Web of Science ID 000228029900022

  View details for PubMedID 15779031

• Magnetic resonance imaging of articular cartilage of the knee: Comparison between fat-suppressed three-dimensional SPGR imaging, fat-suppressed FSE imaging, and fat-suppressed three-dimensional DEFT imaging, and correlation with arthroscopy JOURNAL OF MAGNETIC RESONANCE IMAGING Yoshioka, H., Stevens, K., Hargreaves, B. A., Steines, D., Genovese, M., Dillingham, M. F., Winalski, C. S., Lang, P. 2004; 20 (5): 857-864

  Abstract

  To compare signal-to-noise ratios (S/N) and contrast-to-noise ratios (C/N) in various MR sequences, including fat-suppressed three-dimensional spoiled gradient-echo (SPGR) imaging, fat-suppressed fast spin echo (FSE) imaging, and fat-suppressed three-dimensional driven equilibrium Fourier transform (DEFT) imaging, and to determine the diagnostic accuracy of these imaging sequences for detecting cartilage lesions in osteoarthritic knees, as compared with arthroscopy.Two sagittal fat-suppressed FSE images (repetition time [TR] / echo time [TE], 4000/13 [FSE short TE] and 4000/39 [FSE long TE]), sagittal fat-suppressed three-dimensional SPGR images (60/5, 40 degrees flip angle), and sagittal fat-suppressed echo-planar three-dimensional DEFT images (400/21.2) were acquired in 35 knees from 28 patients with osteoarthritis of the knee. The S/N efficiencies (S/Neffs) of cartilage, synovial fluid, muscle, meniscus, bone marrow, and fat tissue, and the C/N efficiencies (C/Neffs) of these structures were calculated. Kappa values, exact agreement, sensitivity, specificity, positive predictive value, and negative predictive value were determined by comparison of MR grading with arthroscopic results.The synovial fluid S/Neff on fat-suppressed FSE short TE images, fat-suppressed FSE long TE images, and fat-suppressed three-dimensional DEFT images showed similar values. Fat-suppressed three-dimensional DEFT images showed the highest fluid-cartilage C/Neff of all sequences. All images showed fair to good agreement with arthroscopy (kappa, 0.615 in FSE short TE, 0.601 in FSE long TE, 0.583 in three-dimensional SPGR, and 0.561 in three-dimensional DEFT). Although the sensitivity of all sequences was high (100% in FSE short TE, FSE long TE, and DEFT; 96.7% in SPGR), specificity was relatively low (67.6% in FSE short TE and FSE long TE; 85.3% in SPGR; 58.3% in DEFT). The peripheral area of bone marrow edema or whole area of bone marrow edema on fat-suppressed FSE images was demonstrated as low or iso-signal intensity on fat-suppressed three-dimensional DEFT images.Fat-suppressed three-dimensional SPGR imaging and fat-suppressed FSE imaging showed high sensitivity and high negative predictive values, but relatively low specificity. The Kappa value and exact agreement was the highest on fat-suppressed FSE short TE images. Fat-suppressed three-dimensional DEFT images showed results similar to the conventional sequences.

  View details for DOI 10.1002/jmri.20193

  View details for Web of Science ID 000224762700017

  View details for PubMedID 15503323

• Articular cartilage of knee: Normal patterns at MR imaging that mimic disease in healthy subjects and patients with osteoarthritis RADIOLOGY Yoshioka, H., Stevens, K., Genovese, M., Dillingham, M. F., Lang, P. 2004; 231 (1): 31-38

  Abstract

  To evaluate normal magnetic resonance (MR) imaging findings that may mimic articular cartilage diseases in healthy subjects and patients with osteoarthritis of the knee.Sagittal fat-suppressed intermediate-weighted fast spin-echo (FSE) (repetition time msec/echo time [TE] msec, 4,000/13), sagittal T2-weighted FSE (4,000/39), and sagittal fat-suppressed three-dimensional (3D) spoiled gradient-echo (SPGR) (60/5, 40 degrees flip angle) MR images were acquired in 28 patients and four volunteers. FSE images with a TE of 13 msec were considered "short-TE images"; those with a TE of 39 msec were considered "long-TE images." Presence of normal MR imaging appearance of articular cartilage was determined by one author. Contrast between cartilage and adjacent structures (meniscus, joint capsule, synovial fluid, muscle) was calculated in posterior regions of the femoral condyle on images obtained with each sequence; Wilcoxon signed rank testing was performed.The following appearances were observed in patients with knee osteoarthritis (on short-TE FSE, long-TE FSE, and SPGR MR images, respectively): (a) ambiguity of surface contour in posterior region of the femoral condylar cartilage (in zero, zero, and 20 patients), (b) linear area of high signal intensity in deep zone adjacent to subchondral bone of femoral condyle (in zero, zero, and 26 patients), (c) pseudolaminar appearance in posterior region of femoral condylar cartilage (in seven, nine, and 24 patients), (d) truncation artifact in patellofemoral compartment (in seven, six, and 27 patients), (e) susceptibility artifact on cartilage surface caused by air or metal (in three, three, and 11 patients), (f) decreased signal intensity in distal part of trochlear cartilage (in 28, 28, and 28 patients), (g) cartilage thinning adjacent to the anterior horn of the lateral meniscus (in 19, 19, and 21 patients), and (h) focal cartilage flattening in posterior region of femoral condyle (in 16, 16, and nine patients). Cartilage-meniscus and cartilage-synovial fluid contrast was significantly higher on fat-suppressed FSE than on fat-suppressed 3D SPGR MR images (P <.001).Fat-suppressed FSE and 3D SPGR MR images showed nonuniform signal intensity arising from articular cartilage and cartilage thinning, both of which could mimic disease.

  View details for DOI 10.1148/radiol.2311020453

  View details for Web of Science ID 000220394300006

  View details for PubMedID 15068938

• Power Doppler ultrasound of rheumatoid synovitis: quantification of therapeutic response BRITISH JOURNAL OF RADIOLOGY Teh, J., Stevens, K., Williamson, L., Leung, J., McNally, E. G. 2003; 76 (912): 875-879

  Abstract

  The aim of this study is to quantify power Doppler assessment of therapeutic response in rheumatoid synovitis. 13 patients (6 male, 7 female) with rheumatoid arthritis, who had an acute exacerbation of small joint synovitis in the hands, were examined with quantitative power Doppler, before and after intravenous corticosteroid treatment. All patients were examined by a single radiologist, using an ATL HDI 5000 ultrasound machine (ATL, Boswell). The images were analysed using a specially developed software package (HDI Lab), which quantifies power Doppler signal. All patients improved clinically following treatment, which was reflected in functional disability scores, and in the C-reactive protein levels and erythrocyte sedimentation rate. In all cases, there was a significant decrease in synovial vascularity as measured by the mean amplitude of signal on quantitative power Doppler. Quantitative power Doppler may allow objective assessment of treatment in small joint synovitis.

  View details for DOI 10.1259/bjr/40466706

  View details for Web of Science ID 000188590400005

  View details for PubMedID 14711774

• Imaging of the articular cartilage in osteoarthritis of the knee joint: 3D spatial-spectral spoiled gradient-echo vs. fat-suppressed 3D spoiled gradient-echo MR imaging JOURNAL OF MAGNETIC RESONANCE IMAGING Yoshioka, H., Alley, M., Steines, D., Stevens, K., Rubesova, E., Genovese, M., Dillingham, M. F., Lang, P. 2003; 18 (1): 66-71

  Abstract

  To compare three-dimensional (3D) spatial-spectral (SS) spoiled gradient-recalled acquisition in the steady state (SPGR) imaging with fat-suppressed 3D SPGR sequences in MR imaging of articular cartilage of the knee joint in patients with osteoarthritis.MR images of six patients with osteoarthritis of the knee were prospectively examined with a 1.5T MR scanner. For quantitative analyses, the signal-to-noise ratios, contrast-to-noise ratios, and contrast of cartilage and adjacent structures including meniscus, synovial fluid, muscle, fat tissue, and bone marrow were measured.In patients with osteoarthritis, 3DSS-SPGR images demonstrated higher spatial resolution and higher mean signal-to-noise (S/N) ratios (cartilage, 24.9; synovial fluid, 12.3; muscle, 20.7; meniscus, 21.6), with shorter acquisition times (7 minutes 20 seconds), when compared to fat-suppressed 3D SPGR images (cartilage, 22.3; synovial fluid, 10.8; muscle, 16.7; meniscus, 13.4).3DSS-SPGR imaging is a promising method for evaluating cartilage pathology in patients with osteoarthritis of the knee and has the potential to replace fat-suppressed 3D SPGR imaging.

  View details for DOI 10.1002/jmri.10320

  View details for Web of Science ID 000183899500008

  View details for PubMedID 12815641

• Subchondral fractures in osteonecrosis of the femoral head: Comparison of radiography, CT, and MR imaging AMERICAN JOURNAL OF ROENTGENOLOGY Stevens, K., Tao, C., Lee, S. U., Salem, N., Vandevenne, J., Cheng, C., Neumann, G., Alexandre-Valentrin-Opran, Lang, P. 2003; 180 (2): 363-368

  Abstract

  Our objective was to compare the sensitivity of unenhanced radiography, CT, and MR imaging in revealing subchondral fractures.Forty-five subjects with stage I and stage II osteonecrosis of the femoral head were included in the study as part of a multicenter clinical trial to evaluate the effectiveness of recombinant human bone morphogenetic protein as an adjuvant treatment to core decompression. Patients were evaluated with radiography, CT, and MR imaging 6 and 12 months after surgery.At 6 months, 18 fractures were shown on CT scans, but only 12 were detected on radiographs and six, on MR images. At 12 months, 20 subchondral fractures were detected on CT scans, but only 17 were seen on radiographs and 11, on MR images. Compared with CT, MR imaging has a sensitivity and specificity of 38% and 100%, and unenhanced radiography has a sensitivity and specificity of 71% and 97%, respectively. On T2-weighted MR images, the subchondral fractures were visualized as crescentic high-signal-intensity lines, and in all patients, on the corresponding CT scans, the fracture clearly breached the femoral cortex.CT reveals more subchondral fractures in osteonecrosis of the femoral head than unenhanced radiography or MR imaging. The high-signal-intensity line seen on T2-weighted MR images appears to represent fluid accumulating in the subchondral fracture, which may indicate a breach in the overlying articular cartilage.

  View details for Web of Science ID 000180753200015

  View details for PubMedID 12540435

• Gd-labeled liposomes for monitoring liposome-encapsulated chemotherapy: Quantification of regional uptake in tumor and effect on drug delivery Contrast Media Research Conference Rubesova, E., Berger, F., Wendland, M. F., Hong, K. L., Stevens, K. J., Gooding, C. A., Lang, P. ELSEVIER SCIENCE INC. 2002: S525–S527

  View details for Web of Science ID 000177420700083

  View details for PubMedID 12188328

• Tumoral enthesopathy in psoriasis RHEUMATOLOGY Stevens, K. J., Smith, S. L., Preston, B. J., Deighton, C. 2001; 40 (3): 342-344

  View details for Web of Science ID 000167965200017

  View details for PubMedID 11285385

• Imaging of plant-thorn synovitis SKELETAL RADIOLOGY Stevens, K. J., Theologis, T., McNally, E. G. 2000; 29 (10): 605-608

  Abstract

  We describe a case of plant-thorn synovitis of the elbow resulting from a thorn injury. This caused recurrent pain and swelling of the elbow over a 3-month period. A magnetic resonance imaging examination was initially requested to exclude septic arthritis, and demonstrated a joint effusion, synovitis, and a 2-cm linear opacity embedded in the synovium. Ultrasound was performed prior to surgery to confirm these findings and provide accurate localization of the thorn fragment, later removed at surgery. To our knowledge this is the first example of this condition that has been confirmed by radiological imaging prior to surgery.

  View details for Web of Science ID 000165478400010

  View details for PubMedID 11127686

• Bilateral fractures of the middle phalanx of the middle finger in an adolescent climber AMERICAN JOURNAL OF SPORTS MEDICINE Chell, J., Stevens, K., Preston, B., Davis, T. R. 1999; 27 (6): 817-819

  View details for Web of Science ID 000083719300023

  View details for PubMedID 10569373

• Is mammography of value in women with disseminated cancer of unknown origin? CLINICAL ONCOLOGY Stevens, K. J., Smith, S. L., Denley, H., Pinder, S. E., Evans, A. J., Chan, S. Y. 1999; 11 (2): 90-92

  Abstract

  Mammography is often requested to try to identify occult primary breast carcinoma in women with metastatic cancer of unknown primary site. This study aimed to investigate whether mammography is of use in these patients in identifying the breast as the origin of the metastatic disease. Thirty-one women with a working diagnosis of metastatic cancer underwent mammography in an attempt to determine the primary site. None of these women had a palpable breast mass. The site of presentation, pathological type of tumour, site of origin, and benefit of mammography and mammography-provoked biopsy were clarified for each patient. The patients were also followed up to determine survival. The commonest sites of presentation were lung (45%), lymph nodes (19%) and abdomen (16%). The primary sites of these cancers were identified with confidence in 27 patients (87%). The commonest known primary tumour sites were lung (45%), breast (16%) and ovary (16%). Abnormal mammograms were detected in four patients (13%), but three of these did not have breast cancer. In one, the site of origin remained indeterminate, as either breast or lung. Five (16%) had a confident diagnosis of breast carcinoma; all of these women had normal mammograms. We conclude that mammography in women presenting with metastatic disease from an unknown primary site is unhelpful and is not recommended. Furthermore, we could not demonstrate its value in women presenting with axillary lymphadenopathy.

  View details for Web of Science ID 000083698700005

  View details for PubMedID 10378633

• Magnetic resonance imaging to customize lower limb modelling in cerebral palsy. Gait and Posture Harrington M, Stevens K, Thompson N, O'Connor J, Theologic T. 1999; 10: 84 - 85
• CT imaging and three-dimensional reconstructions of shoulders with anterior glenohumeral instability CLINICAL ANATOMY Stevens, K. J., Preston, B. J., Wallace, W. A., Kerslake, R. W. 1999; 12 (5): 326-336

  Abstract

  Glenohumeral instability is a common occurrence following anterior dislocation of the shoulder joint, particularly in young men. The bony abnormalities encountered in patients with glenohumeral instability can be difficult to detect with conventional radiography, even with special views. The aim of our study was to evaluate the bony abnormalities associated with glenohumeral instability using CT imaging with 3-D reconstruction images. We scanned 11 patients with glenohumeral instability, one with bilateral symptoms; 10 were male, one female, and their ages ranged from 18-66 years. Contiguous 3 mm axial slices of the glenohumeral joint were taken at 2 mm intervals using a Siemens Somatom CT scanner. In the 12 shoulders imaged, we identified four main abnormalities. A humeral-head defect or Hill-Sachs deformity was seen in 83% cases, fractures of the anterior glenoid rim in 50%, periosteal new bone formation secondary to capsular stripping in 42%, and loose bone fragments in 25%. Manipulation of the 3-D images enabled the abnormalities to be well seen in all cases, giving a graphic visualization of the joint, and only two 3-D images were needed to demonstrate all the necessary information. We feel that CT is the imaging modality most likely to show all the bone abnormalities associated with glenohumeral instability. These bony changes may lead to the correct inference of soft tissue abnormalities making more invasive examinations such as arthrography unnecessary.

  View details for Web of Science ID 000082326600003

  View details for PubMedID 10462730

• Pneumothorax post transthoracic biopsy: Incidence, detection and management J Diag Radiogr Imag Smith S, Stevens KJ, Manhire AR 1999; 2: 89 - 93
• Magnetic resonance imaging of elephantiasis neuromatosa SKELETAL RADIOLOGY Stevens, K. J., Ludman, C. N., Sully, L., Preston, B. J. 1998; 27 (12): 696-701

  Abstract

  We present the case of a 43-year-old man with neurofibromatosis type 1 who developed elephantiasis neuromatosa of his left leg. The gross limb enlargement was extremely disfiguring, and resulted in such severe disability that he was only able to walk a very short distance using crutches. Previous debulking procedures had resulted in massive blood loss, and prior to attempting further surgical intervention MRI studies were requested. Taking advantage of the excellent tissue characterisation and multiplanar imaging capabilities of MRI, we were able to assess the extent of soft tissue and osseous involvement. The use of recently developed MR angiographic sequences enabled us to non-invasively provide detailed images to assess the relationship of the lesions to the major vessels, as well as the vascular supply and angiographic features of the lesions themselves. This article describes our MRI-based findings, which precluded debulking surgery in this unusual manifestation of neurofibromatosis.

  View details for Web of Science ID 000077909100009

  View details for PubMedID 9921933

• Brown-Sequard syndrome due to traumatic brachial plexus root avulsion INJURY-INTERNATIONAL JOURNAL OF THE CARE OF THE INJURED Stephen, A. B., Stevens, K., Craigen, M. A., Kerslake, R. W. 1997; 28 (8): 557-558

  View details for Web of Science ID 000072481800016

  View details for PubMedID 9616398

• Pseudomyxoma extraperitonei: A lethal complication of mucinous adenocarcinoma of the appendix AMERICAN JOURNAL OF GASTROENTEROLOGY Stevens, K. J., Dunn, W. K., Balfour, T. 1997; 92 (10): 1920-1922

  Abstract

  We report the unusual case of a 56-yr-old man who presented with an appendix abscess. This abscess failed to respond to standard treatment, and recurred despite operative intervention. A colocutaneous fistula developed, which initially discharged frank pus, then began discharging mucus via two cutaneous sinuses. No evidence of malignancy was detected from either repeat curettings or a diagnostic laparotomy. One and a half years after the initial presentation, histologic examination finally revealed mucinous adenocarcinoma of the appendix. We postulate that this malignancy in a retrocecal appendix resulted in a mucocele, which ruptured into the retroperitoneal space and drained via cutaneous sinuses, so-called pseudomyxoma extraperitonei. The patient declined further surgical intervention, and despite initial control by radiotherapy, the tumor spread locally to involve the entire right lower quadrant of the abdomen. The patient eventually died 39 months after the initial presentation.

  View details for Web of Science ID A1997XZ84800035

  View details for PubMedID 9382067

• Bilateral fracture dislocation of the sacroiliac joint SKELETAL RADIOLOGY Stevens, K. J., Preston, B. J., Hahn, D. M. 1997; 26 (9): 556-558

  Abstract

  We present a rare case of a 27-year-old man sustaining a bilateral fracture dislocation of the sacroiliac joints without disruption of the anterior pelvis, following a fall from a height. Reconstructed images in the coronal plane and three-dimensional CT images were invaluable in the diagnosis and assessment of this injury.

  View details for Web of Science ID A1997XY82100010

  View details for PubMedID 9342818

• The ultrasound appearances of galactocoeles BRITISH JOURNAL OF RADIOLOGY Stevens, K., Burrell, H. C., Evans, A. J., Sibbering, D. M. 1997; 70: 239-241

  Abstract

  Galactocoeles are an uncommon cause of breast masses, usually occurring in lactating women. The purpose of this study was to review the ultrasound (US) features of galactocoeles presenting to the Nottingham Breast Unit. Eight women with galactocoeles were scanned during 1994 and 1995. All the scans were abnormal, 50% of lesions were cystic or multicystic, 37% mixed cystic/solid and 13% appeared solid. A fat-fluid level was seen in only one case. Two of the cystic/solid lesions had ill defined solid components, raising the possibility of an intracystic carcinoma. All cases were confirmed by the aspiration of milk and clinical resolution following aspiration.

  View details for Web of Science ID A1997WP55800003

  View details for PubMedID 9166046

• False aneurysm of a lumbar artery following vertebral biopsy. European spine journal Stevens, K. J., Gregson, R. H., Kerslake, R. W. 1997; 6 (3): 205-207

  Abstract

  Vertebral body biopsy is regarded as a simple and relatively safe technique, with a low complication rate. We report the case of an 80-year-old man who developed a false aneurysm of a lumbar artery following biopsy of the fourth lumbar vertebra.

  View details for PubMedID 9258641

• Diagnostic echographique d'une galactocele Journal Francais d'Echographie Stevens KJ, Burrell HC, Evans A, Sibbering DM 1997; 5: 47 - 48
• FEMORAL NERVE PALSY - AN UNUSUAL COMPLICATION OF ANTERIOR LUMBAR INTERBODY FUSION SPINE Papastefanou, S. L., Stevens, K., Mulholland, R. C. 1994; 19 (24): 2842-2844

  Abstract

  Compression neuropathy of the femoral nerve has been reported as an uncommon complication of bleeding into the iliopsoas muscle.The authors detected anatomic reasons of direct injury to the femoral nerve at the lower lumbar level.Keeping the hip in extension during the course of carrying out anterior fusion on a previously failed posterior fusion was considered another causative factor of femoral nerve injury. Anatomical dissection confirmed the likelihood of this injury being produced in this situation.Femoral nerve traction and compression can occur after prolonged compression of the nerve within the psoas muscle stretched between an immobile lower lumbar spine and the lesser trochanter when the hip is kept in extension. In the patients described no other reasons for direct or indirect injury were identified.Although uncommon, the complication should be kept in mind. It can be avoided by intraoperative hip flexion.

  View details for Web of Science ID A1994PY22600020

  View details for PubMedID 7899989

• VOLAR DISLOCATION OF THE LUNATE CAUSING MULTIPLE FLEXOR TENDON RUPTURES - AN UNUSUAL MANIFESTATION OF PYROPHOSPHATE ARTHROPATHY JOURNAL OF HAND SURGERY-BRITISH AND EUROPEAN VOLUME Stevens, K. J., Pathak, G., Davis, T. R. 1994; 19B (2): 195-196

  View details for Web of Science ID A1994NH11000015

• Sciatic nerve palsy caused by haematoma from iliac bone graft donor site. European spine journal Stevens, K. J., Banuls, M. 1994; 3 (5): 291-293

  Abstract

  A 27-year-old woman developed a haematoma-related compressive neuropathy of the right sciatic nerve following the harvesting of a bone graft from the posterior aspect of the right iliac crest. The nerve was compressed in an enclosed compartment between the sciatic notch and the piriformis muscle, which is thought to be involved in the piriformis syndrome. The symptoms improved once the haematoma was evacuated, and this complication stresses the importance of adequate haemostasis of the area from which the bone graft is taken.

  View details for PubMedID 7866855

• Iliolumbar hernia following bone grafting. European spine journal Stevens, K. J., Banuls, M. 1994; 3 (2): 118-119

  Abstract

  A 40-year-old man developed a lumbar hernia through an iliac bone graft donor site. The defect was repaired using an autologous bone graft reinforced by titanium mesh.

  View details for PubMedID 7874549

• THE INCIDENCE OF ABDOMINAL AORTIC-ANEURYSMS BRITISH JOURNAL OF CLINICAL PRACTICE Stevens, K. 1993; 47 (4): 208-210

  Abstract

  The incidence of abdominal aortic aneurysms (AAAs) is increasing, especially in the elderly. This trend has been observed in the United Kingdom, USA, Australia, and Sweden. The increase can be explained partly by an enhanced awareness of the condition and partly by the rising numbers of elderly in the population. In addition, improved diagnostic techniques have enabled earlier detection of aneurysms. But this does not fully explain why we are seeing such a high prevalence of the condition. Evidence for the increase can be obtained from a number of sources, such as routine mortality statistics.

  View details for Web of Science ID A1993MA78800012

  View details for PubMedID 8260341

• A study of Peroneus Tertius British Journal of Clinical Anatomy Stevens K, Platt A, Ellis H 1992; 6 (6): 106 -110
• ALDOSTERONE IS SECRETED INTERMITTENTLY DURING PREGNANCY BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY Stevens, K. J., Paintin, D. B., Few, J. D. 1989; 96 (1): 80-87

  Abstract

  Saliva aldosterone concentration was measured in samples collected at hourly intervals from healthy pregnant women (approximately 26 and 36 weeks gestation) who were going about their normal daily activities, and from some women hospitalized for disorders of pregnancy. In the healthy women diurnal saliva aldosterone fluctuated considerably, the highest values being 2-22 times the lowest on a given day. Because of the known correlation between saliva and plasma aldosterone concentrations we believe that the fluctuating salivary level is indicative of fluctuating plasma levels and that this is due to the intermittent secretion of aldosterone. The rate of decline of saliva aldosterone from peak levels indicated a half life (t 1/2) of 72 (SD 31) min which was not significantly different from that in non-pregnant subjects. The temporal pattern of saliva aldosterone suggests an enhanced response of the zona glomerulosa to the factors that cause aldosterone secretion to fluctuate in non-pregnant subjects, rather than the development of a more potent stimulus to the zona glomerulosa during pregnancy. In addition to hour-to-hour variation there is also substantial day-to-day variation, so that estimation of aldosterone in a single sample of saliva or plasma is of little value during pregnancy. The mean diurnal aldosterone concentration can be estimated from five saliva samples so this measurement presents a convenient technique for the assessment of aldosterone status in pregnancy. In contrast to healthy pregnancy, a patient with pre-eclampsia at 39 weeks gestation showed no elevation of saliva aldosterone above non-pregnant levels at any time during the day.

  View details for Web of Science ID A1989T064100014

  View details for PubMedID 2923844