Bio

Clinical Focus


  • Pediatric Radiology

Professional Education


  • Board Certification: Pediatric Radiology, American Board of Radiology (1995)
  • Fellowship:Boston Children's Hospital (1989) MA
  • Board Certification: Diagnostic Radiology, American Board of Radiology (1987)
  • Residency:University of Texas Medical School at Houston (1987) TX
  • Internship:Jackson Memorial Hospital (1983) FL
  • Medical Education:Pontifica Universidad Javeriana (1981) Colombia

Teaching

2018-19 Courses


Publications

All Publications


  • Fetal suprarenal masses - assessing the complementary role of magnetic resonance and ultrasound for diagnosis. Pediatric radiology Flanagan, S. M., Rubesova, E., Jaramillo, D., Barth, R. A. 2016; 46 (2): 246-254

    Abstract

    To assess the value and complementary roles of fetal MRI and US for characterization and diagnosis of suprarenal masses.We conducted a multi-institutional retrospective database search for prenatally diagnosed suprarenal masses between 1999 and 2012 and evaluated the roles of prenatal US and fetal MRI for characterization and diagnosis, using postnatal diagnosis or surgical pathology as the reference standard. Prenatal US and fetal MRI were assessed for unique findings of each modality.The database yielded 25 fetuses (gestational age 20-37 weeks) with suprarenal masses. Twenty-one fetuses had prenatal US, 22 had MRI, 17 had both. Postnatal diagnoses included nine subdiaphragmatic extralobar sequestrations, seven adrenal hemorrhages, five neuroblastomas (four metastatic), two lymphatic malformations, one duplex kidney with upper pole cystic dysplasia, and one adrenal hyperplasia. Ultrasound was concordant with MRI for diagnoses in 12/17 (70.6%) cases. Discordant diagnoses between US and MRI included three neuroblastomas and two adrenal hemorrhages. In the three neuroblastomas US was equivocal and MRI was definitive for neuroblastoma, demonstrating heterogeneous, intermediate-signal solid masses and liver metastases. In the two cases of adrenal hemorrhage US was equivocal and MRI was definitive with signal characteristics of hemorrhage. In 2/4 neuroblastomas, Doppler US demonstrated a systemic artery suggesting extralobar sequestration; however MRI signal characteristics correctly diagnosed neuroblastoma. All cases of extralobar sequestration were correctly diagnosed by US and MRI.US and MRI both accurately detect suprarenal masses. MRI complements US in equivocal diagnoses and detects additional findings such as liver metastases in neuroblastoma.

    View details for DOI 10.1007/s00247-015-3470-1

    View details for PubMedID 26589304

  • Comparison Between 1.5-T and 3-T MRI for Fetal Imaging: Is There an Advantage to Imaging With a Higher Field Strength? AMERICAN JOURNAL OF ROENTGENOLOGY Victoria, T., Johnson, A. M., Edgar, J. C., Zarnow, D. M., Vossough, A., Jaramillo, D. 2016; 206 (1): 195-201

    Abstract

    Fetal MRI at 3 T is emerging as a promising modality for evaluating fetal anatomy. The objective of this study was to compare the quality of images obtained with commonly used fetal imaging sequences at 1.5 T and 3 T. We hypothesized that the visualization and anatomic detail of fetal structures would be better at 3 T than at 1.5 T.A retrospective search of the radiology department database at our institution identified 58 fetal MRI examinations performed at 3 T to evaluate body abnormalities during the period from July 2012 to February 2014. A blind comparison was conducted between these examinations and 58 1.5-T MRI examinations of age-matched fetuses undergoing evaluation for similar abnormalities during the same period. The anatomic structures analyzed included the bowel, liver, kidney, airway, cartilage, and spine. Scores for the depiction of anatomic structures ranged from 0 to 4, with 4 denoting the best depiction.Fetal imaging at 3 T was associated with higher imaging scores in the evaluation of the cartilage and spine when single-shot turbo spin-echo (SSTSE) and steady-state free precession (SSFP) sequences were used and in the assessment of most structures (e.g., bowel, liver, kidney, cartilage, and spine) when SSFP sequences were used. The mean scores for all structures evaluated with the use of SSTSE sequences were higher when MRI was performed at 3 T than at 1.5 T; similar findings were noted when SSFP sequences were used. Evaluation of imaging scores with regard to gestational age showed that scores improved with increasing gestational age on 1.5-T MRI but not on 3-T MRI. Overall, more imaging artifacts were found when imaging was performed at 3 T than at 1.5 T.An overall advantage to performing fetal imaging at 3 T was made evident by the higher imaging scores obtained with 3-T MRI versus 1.5-T MRI when different fetal anatomic structures were evaluated. These higher scores were predominantly associated with use of SSFP sequences. The findings of this study and future advancements in MRI software and 3-T protocols may allow optimal visualization and examination of fetal pathologic abnormalities, thus better identifying fetal and maternal needs both prenatally and postnatally.

    View details for DOI 10.2214/AJR.14.14205

    View details for Web of Science ID 000367181400039

    View details for PubMedID 26700352

  • Utility of unenhanced fat-suppressed T1-weighted MRI in children with sickle cell disease - can it differentiate bone infarcts from acute osteomyelitis? PEDIATRIC RADIOLOGY Delgado, J., Bedoya, M. A., Green, A. M., Jaramillo, D., Ho-Fung, V. 2015; 45 (13): 1981-1987

    Abstract

    Children with sickle cell disease (SCD) are at risk of bone infarcts and acute osteomyelitis. The clinical differentiation between a bone infarct and acute osteomyelitis is a diagnostic challenge. Unenhanced T1-W fat-saturated MR images have been proposed as a potential tool to differentiate bone infarcts from osteomyelitis.To evaluate the reliability of unenhanced T1-W fat-saturated MRI for differentiation between bone infarcts and acute osteomyelitis in children with SCD.We retrospectively reviewed the records of 31 children (20 boys, 11 girls; mean age 10.6 years, range 1.1-17.9 years) with SCD and acute bone pain who underwent MR imaging including unenhanced T1-W fat-saturated images from 2005 to 2010. Complete clinical charts were reviewed by a pediatric hematologist with training in infectious diseases to determine a clinical standard to define the presence or absence of osteomyelitis. A pediatric radiologist reviewed all MR imaging and was blinded to clinical information. Based on the signal intensity in T1-W fat-saturated images, the children were further classified as positive for osteomyelitis (low bone marrow signal intensity) or positive for bone infarct (high bone marrow signal intensity).Based on the clinical standard, 5 children were classified as positive for osteomyelitis and 26 children as positive for bone infarct (negative for osteomyelitis). The bone marrow signal intensity on T1-W fat-saturated imaging was not significant for the differentiation between bone infarct and osteomyelitis (P = 0.56). None of the additional evaluated imaging parameters on unenhanced MRI proved reliable in differentiating these diagnoses.The bone marrow signal intensity on unenhanced T1-W fat-saturated MR images is not a reliable criterion to differentiate bone infarcts from osteomyelitis in children.

    View details for DOI 10.1007/s00247-015-3423-8

    View details for Web of Science ID 000365754700012

    View details for PubMedID 26209118

  • Quantification of Bone Marrow Involvement in Treated Gaucher Disease With Proton MR Spectroscopy: Correlation With Bone Marrow MRI Scores and Clinical Status AMERICAN JOURNAL OF ROENTGENOLOGY Jaramillo, D., Bedoya, M. A., Wang, D., Pena, A. H., Delgado, J., Jaimes, C., Ho-Fung, V., Kaplan, P. 2015; 204 (6): 1296-1302

    Abstract

    The objective of our study was to use proton MR spectroscopy (MRS) to quantitatively evaluate bone marrow infiltration by measuring the fat fraction (FF) and to compare the FF with semiquantitative bone marrow MRI scores and clinical status in children treated for type 1 Gaucher disease (GD).Over a 2-year period, we prospectively evaluated 10 treated GD patients (six males, four females; median age, 15.1 years) and 10 healthy age-matched control subjects (five males, five females; median age, 15.3 years) using 3-T proton MRS of L5 and the femoral neck. Water and lipid AUCs were measured to calculate the FF. Two blinded pediatric musculoskeletal radiologists performed a semiquantitative analysis of the conventional MR images using the bone marrow burden score and modified Spanish MRI score. We evaluated symptoms, spleen and liver volumes, platelet levels, hemoglobin levels, and bone complications.In the femur, the FF was higher in the control subjects (median, 0.71) than the GD patients (0.54) (p = 0.02). In L5, the difference in FF--higher FF in control subjects (0.37) than in GD patients (0.26)--was not significant (p = 0.16). In both groups and both regions, the FF increased with patient age (p < 0.02). Semiquantitative scores showed no differences between control subjects and treated GD patients (p > 0.11). Eight of 10 GD patients were asymptomatic and two had chronic bone pain. The median age of patients at symptom onset was 4.0 years, the median age of patients at the initiation of enzyme replacement therapy was 4.3 years, and the median treatment duration was 10.2 years. Hemoglobin level, platelet count, and liver volume at MRI were normal. Mean pretreatment spleen volume (15.4-fold above normal) decreased to 2.8-fold above normal at the time of MRI (p = 0.01).Proton MRS detected FF differences that were undetectable using conventional MRI; for that reason, proton MRS can be used to optimize treatment of GD patients.

    View details for DOI 10.2214/AJR.14.13563

    View details for Web of Science ID 000360472100044

    View details for PubMedID 26001241

  • Diffusion-Tensor Imaging of the Growing Ends of Long Bones: Pilot Demonstration of Columnar Structure in the Physes and Metaphyses of the Knee RADIOLOGY Jaimes, C., Berman, J. I., Delgado, J., Ho-Fung, V., Jaramillo, D. 2014; 273 (2): 491-501

    Abstract

    To determine the feasibility of using in vivo diffusion-tensor imaging and tractography of the physis to examine changes related to rate of growth, location, and age.This retrospective study was institutional review board approved and HIPAA compliant and the requirement for informed consent was waived. Diffusion-tensor imaging of the knee was performed at 3.0 T in 31 subjects (nine boys and 22 girls) with a median age of 13.6 years. The mean ages of boys and girls were 14.7 years (range, 12.0-18.3 years) and 13.2 years (range, 7.0-18.6 years), respectively. Regions of interest were placed in the physis of the tibia and femur, and in the epiphyseal and articular cartilage of these bones. Tractography was performed by using a fractional anisotropic threshold of 0.15 and an angle threshold of 40°. The tractographic patterns were qualitatively evaluated and changes related to age were described. The tract-based apparent diffusion coefficient, fractional anistropy, tensor eigenvalues, and tract length were measured. Diffusion parameters were compared between the center and periphery of the physis, and between the distal femur and proximal tibia.Tractography resulted in parallel tracts in the physis and the adjacent metaphysis. Tractographic pattern changed with age, with individuals approaching physeal closure having shorter tracts in a random arrangement. Patterns of tractography varied with age in the femur (P < .001) and tibia (P < .001). Femoral tracts (median length, 6.5 mm) were longer than tibial tracts (median length, 4.3 mm) (P < .001). Tracts in the periphery of the physes were longer than those in the center (femur, P = .005; tibia, P = .004). In the physis of the femur and tibia, a significant age-related decrease was observed in apparent diffusion coefficient (P < .001 for both), axial diffusion (femur, P = .001; tibia, P < .001), and transverse diffusion [P < .001 for both]), and an age-related increase was seen in fractional anistropy (P < .001, for both).Diffusion-tensor imaging shows the columnar microstructure of the physis and adjacent metaphysis, and provides further insight into normal growth.

    View details for DOI 10.1148/radiol.14132136

    View details for Web of Science ID 000345069800022

    View details for PubMedID 25102295

  • Dynamic Gadolinium-Enhanced MRI of the Proximal Femur: Preliminary Experience in Healthy Children AMERICAN JOURNAL OF ROENTGENOLOGY Bedoya, M. A., Jaimes, C., Khrichenko, D., Delgado, J., Dardzinski, B. J., Jaramillo, D. 2014; 203 (4): W440-W446

    Abstract

    The purpose of this study is to use dynamic contrast-enhanced MRI to evaluate the perfusion characteristics of the proximal femur in the growing skeleton.We evaluated 159 subjects (mean age, 5.67 years) who underwent a well-controlled protocol of contrast-enhanced MRI of the abdomen and hips. Perfusion and permeability parameters (enhancement ratio peak, AUC, time to peak, and rate of extraction) for six regions of the proximal femur were calculated.A decrease with age was found for all contrast kinetics parameters in all regions (p < 0.001). Perfusion parameters differed between the regions (p < 0.001). The highest perfusion and permeability parameters were found in the metaphyseal spongiosa, metaphyseal marrow, and periosteum. The metaphyseal spongiosa had a highly vascular pattern of enhancement and showed the highest enhancement ratio peak, AUC, and rate of extraction and the lowest time to peak. The metaphyseal marrow showed a vascular pattern of enhancement with a lower peak compared with the metaphyseal spongiosa. The periosteum showed prompt nonvascular contrast enhancement that reached a plateau that remained elevated.The highest enhancement was seen in areas involved with growth: the metaphyseal spongiosa, which is related to endochondral ossification, and the periosteal cambium, which is related to membranous ossification. The enhancement characteristics are radically different: in the spongiosa; enhancement is brisk and declines, with a vascular pattern, whereas contrast uptake increases with time in the periosteum. Recognition of normal enhancement patterns of the proximal femur is important for distinguishing normal development from pathologic processes.

    View details for DOI 10.2214/AJR.13.12341

    View details for Web of Science ID 000345523500013

    View details for PubMedID 25247974

  • Fetal magnetic resonance imaging: jumping from 1.5 to 3 tesla (preliminary experience) PEDIATRIC RADIOLOGY Victoria, T., Jaramillo, D., Roberts, T. P., Zarnow, D., Johnson, A. M., Delgado, J., Rubesova, E., Vossough, A. 2014; 44 (4): 376-386

    Abstract

    Several attempts have been made at imaging the fetus at 3 T as part of the continuous search for increased image signal and better anatomical delineation of the developing fetus. Until very recently, imaging of the fetus at 3 T has been disappointing, with numerous artifacts impeding image analysis. Better magnets and coils and improved technology now allow imaging of the fetus at greater magnetic strength, some hurdles in the shape of imaging artifacts notwithstanding. In this paper we present the preliminary experience of evaluating the developing fetus at 3 T and discuss several artifacts encountered and techniques to decrease them, as well as safety concerns associated with scanning the fetus at higher magnetic strength.

    View details for DOI 10.1007/s00247-013-2857-0

    View details for Web of Science ID 000333529100002

    View details for PubMedID 24671739

  • Image interpretation session - Sunday, November 27, 2005 RADIOGRAPHICS Rubin, G. D., Bradley, W. G., Foley, W. D., Herold, C. J., Jaramillo, D., Seeger, L. L. 2005; 25 (5): 1437-1447

    Abstract

    The Sunday afternoon Image Interpretation Session has been a high point of the annual meeting of the Radiological Society of North America for over 65 years. A panel of five experts has been selected, representing the very best from the fields of neurologic, abdominal, thoracic, pediatric, and musculoskeletal radiology. Each panelist will dazzle us with an insightful analysis of two difficult cases in their area of expertise. The panelists are to be lauded for their bravery in subjecting their diagnostic acumen to the scrutiny of the thousands of radiologists in the audience. The cases, representing a diverse spectrum of diseases and disease manifestations, were selected from recent clinical imaging studies performed at the Stanford University Medical Center or the Lucille Salter Packard Children's Hospital. This session celebrates the skills of diagnostic radiologists worldwide, who are called on daily to amalgamate disparate clinical information with complex imaging data into focused differential diagnoses and effective treatment planning. We hope that these cases will serve to illustrate the central role that expert image interpretation plays in the care of patients. We welcome our audience of RSNA attendees, readers of RadioGraphics, and cyberspace denizens to join with our experts in solving these medical puzzles and to enjoy the excitement of unraveling the unknown.

    View details for DOI 10.1148/rg.255055941

    View details for Web of Science ID 000236951300024

    View details for PubMedID 16163794