Clinical Focus

  • Minimally Invasive Surgery
  • Brain and Spinal Oncology/ Metastases
  • Cyberknife Radiosurgery
  • Cancer > Neuro Oncology
  • Neurosurgery

Academic Appointments

Administrative Appointments

  • Director, Spinal Oncology Surgery (2010 - Present)
  • Director, Minimally Invasive Spinal Surgery (2009 - Present)

Honors & Awards

  • Goldberg Award, Northwestern Memorial Hospital (-)
  • Eckenhoff Award, Northwestern University Medical School (-)

Professional Education

  • Residency:Northwestern Memorial Hospital (2008) IL
  • Fellowship:Northwestern Memorial Hospital (2007) IL
  • Internship:Northwestern Memorial Hospital (2003) IL
  • Medical Education:Northwestern University Medical School (2002) IL
  • Fellowship, Northwestern Memorial Hospital, Minimally Invasive / Complex Spinal Reconstruction Fellow (2007)
  • Residency, Northwestern Memorial Hospital, Neurological Surgery (2008)
  • M.D, Northwestern University, Feinberg School of Medicine (2002)

Research & Scholarship

Current Research and Scholarly Interests

Dr. Mindea’'s primary clinical interests include the management of primary and metastatic brain and spinal tumors (cyberknife/ surgical oncology) and include minimally invasive spinal surgery techniques for degenerative disease and scoliosis.

His research interests include the development medical devices and cutting-edge technologies for the treatment of various neurological disorders and tumors.

In 2009, Dr Mindea performed the first Endoscopic Odontoidectomy surgery at Stanford University. His clinical and research interests include "En Bloc" resections of various tumors to achieve maximal tumor removal reducing the chance for tumor recurrence.

In 2010, Dr Mindea also performed the first "En Bloc Total Sacrectomy" for Tumor with reconstruction at Stanford University.


2013-14 Courses

Graduate and Fellowship Programs


Journal Articles

  • rhBMP-2 -induced Radiculitis in Elective Minimally Invasive Transforaminal Lumbar Interbody Fusions: A Series Review Spine Mindea SA, Shih P, Song JK 2009; July 1
  • Unruptured arteriovenous malformation in a patient presenting with obstructive hydrocephalus. Case report and review of the literature. Neurosurgical focus Mindea, S. A., Yang, B. P., Batjer, H. H. 2007; 22 (4): E11-?


    The authors report on a patient harboring an unruptured cortical arteriovenous malformation (AVM), who had presented with obstructive hydrocephalus due to compression of the cerebral aqueduct by a large venous varix. Although patients with ruptured AVMs are known to either present with or later suffer from obstructive hydrocephalus, those with unruptured AVMs who present in this manner are quite rare. Moreover, hydrocephalus caused by a venous varix draining an AVM, to our knowledge, has never been previously reported in the literature. This report serves to illustrate two primary points, namely, that tortuous venous varices draining AVMs can result in obstructive hydrocephalus and that this unusual circumstance can be fostered in the setting of venous outflow obstruction.

    View details for PubMedID 17613189

  • Granular cell tumor involving the axillary nerve: an unusual occurrence. Case report. Neurosurgical focus Mindea, S. A., Kaplan, K. J., Howard, M. A., O'Leary, S. T. 2007; 22 (6): E24-?


    Granular cell tumors (GCTs) are benign lesions that, paradoxically, despite originating from the Schwann cell, are most commonly seen in nonneuronal tissue including the skin, subcutaneous tissue, and tongue. Their presence in the brachial plexus is quite rare, but their involvement of peripheral nerves is exceptional. The authors report on a case of GCT involving the axillary nerve in a 54-year-old woman who underwent complete resection of the lesion. To the author's knowledge, this case marks the first report of a GCT involving the axillary nerve. Aspects pertaining to the radiographic and histopathological features as well as the surgical management of this lesion are discussed.

    View details for PubMedID 17613216

  • Medical management of Cushing disease. Neurosurgical focus Gross, B. A., Mindea, S. A., Pick, A. J., Chandler, J. P., Batjer, H. H. 2007; 23 (3): E10-?


    Although transsphenoidal excision of the adrenocorticotropic hormone (ACTH)-producing neoplasm is often the treatment of choice in patients with Cushing disease, medical management is itself a useful preoperative temporizing measure, an option for long-term management in nonsurgical candidates, and an option for patients in whom surgery and/or radiotherapy have failed. Three pathophysiologically based approaches exist in the research literature--neuro-modulation to limit ACTH levels, adrenal enzyme inhibition, and glucocorticoid receptor antagonism. Unfortunately, the neuromodulatory approach involving agents such as bromocriptine, cyproheptadine, octreotide, and valproate has yielded only suboptimal results. Glucocorticoid receptor antagonism remains in its infancy but may overall be limited by side effects and a resultant increase in ACTH and cortisol levels. Adrenal enzyme inhibitors, however, offer substantial future promise in the management of Cushing disease but are limited by the potential need to use them indefinitely and by dose-tolerance effects. Although etomidate is a potential intravenous alternative for acute cortisol level control, ketoconazole has shown efficacy in the long-term treatment of patients with the disease. Metyrapone and/or aminoglutethimide can be added to ketoconazole if additional control is needed. If success is still not achieved, the potent adrenolytic agent often used for adrenocortical carcinomas, mitotane, is another alternative.

    View details for PubMedID 17961023

  • Cerebral cavernous malformations: clinical insights from genetic studies. Neurosurgical focus Mindea, S. A., Yang, B. P., Shenkar, R., Bendok, B., Batjer, H. H., Awad, I. A. 2006; 21 (1)


    Familial disease is responsible for one third to one half of cerebral cavernous malformation (CCM) cases presenting to clinical attention. Much has been learned in the past decade about the genetics of these cases, which are all inherited in an autosomal dominant pattern, at three known chromosome loci. Unique features of inherited CCMs in Hispanic-Americans of Mexican descent have been described. The respective genes for each locus have been identified and preliminary observations on disease pathways and mechanisms are coming to light, including possible explanations for selectivity of neural milieu and relationships to endothelial layer abnormalities. Mechanisms of lesion genesis in cases of genetic predisposition are being investigated, with evidence to support a two-hit model emerging from somatic mutation screening of the lesions themselves and from lesion formation in transgenic murine models of the disease. Other information on potential inflammatory factors has emerged from differential gene expression studies. Unique phenotypic features of solitary versus familial cases have emerged: different associations with venous developmental anomaly and the exceptionally high penetrance rates that are found in inherited cases when high-sensitivity screening is performed with gradient echo magnetic resonance imaging. This information has changed the landscape of screening and counseling for patients and their families, and promises to lead to the development of new tools for predicting, explaining, and modifying disease behavior.

    View details for PubMedID 16859247

  • Indications and rationale for use of vascularized fibula bone flaps in cervical spine arthrodeses PLASTIC AND RECONSTRUCTIVE SURGERY Lee, M. J., Ondra, S. L., Mindea, S. A., Fine, N. A., Dumanian, G. A. 2005; 116 (1): 1-7


    Anterior cervical spine arthrodesis for large defects using autograft or allograft fibula for anterior structural support is a widely accepted procedure. In unique demand situations, a vascularized fibular flap is regarded as an "improvement" to the standard procedure. While a vascularized flap does deliver living tissue to the region, it does so with added potential morbidity and increased technical demand. The indications in the literature for this procedure have not been clearly defined. In this article, the authors review specific high-demand situations where they believe a vascularized flap is indicated. They also review patient outcomes after this procedure.Fibular free flaps were used in six patients with failed previous cervical spine arthrodeses. Three of the six patients had preoperative radiation therapy, and one received postoperative radiation treatment. All six patients had tumor and/or osteomyelitis present.One patient died of intraoperative hypotension 3 days after a successful free flap transfer during an elective posterior spine instrumentation procedure. One flap was lost from a venous thrombosis, and the patient was then treated successfully with a second fibular free flap. Clinical and radio-graphic evidence of fusion was obtained at 3 months in the five surviving patients, and neurologic function remained stable or improved.Analyzing their results and the literature, the authors propose that fibular free flaps are indeed a useful adjunct in difficult cervical spine stabilization procedures. Indications for this flap include combinations of the following situations: failed prior attempts at fusion, anterior cervical arthrodeses of three or more vertebral levels, osteomyelitis of the spine, and tumor cases when the spine has been or will be radiated.

    View details for DOI 10.1097/01.PRS.0000169710.53269.BC

    View details for Web of Science ID 000230254100001

    View details for PubMedID 15988237

  • Lumbosacropelvic junction reconstruction resulting in early ambulation for patients with lumbosacral neoplasms or osteomyelitis. Neurosurgical focus Mindea, S. A., Salehi, S. A., Ganju, A., Rosner, M. K., O'Shaughnessy, B. A., Jorge, A., Ondra, S. L. 2003; 15 (2): E6-?


    Lumbosacropelvic junction instability may result from a variety of disease processes including primary and metastatic sacral tumors and degenerative disease. Regardless of the origin of the disease, restoring or maintaining spinal stability at this junction is essential for normal translation of axial forces from the lumbar spine and sacrum to the pelvis. Spinal stability is also critical for maintaining structural integrity, preventing neurological function deterioration, and alleviating resultant mechanical or axial pain. In this report, the authors describe one option for safe and effective spinal pelvic stabilization by using a transiliac rod and iliac bolt construct, which results in early postoperative ambulation, preserved neurological function, and reduced axial pain in selected patients.

    View details for PubMedID 15350037

  • Spontaneous intracranial hypotension secondary to anterior thoracic osteophyte: Resolution after primary dural repair via posterior approach. International journal of surgery case reports Veeravagu, A., Gupta, G., Jiang, B., Berta, S. C., Mindea, S. A., Chang, S. D. 2013; 4 (1): 26-29


    Spontaneous intracranial hypotension (SIH) is an uncommon syndrome widely attributed to CSF hypovolemia, typically secondary to spontaneous CSF leak. Although commonly associated with postural headache and variable neurological symptoms, one of the most severe consequences of SIH is bilateral subdural hematomas with resultant neurological deterioration.We present the case of a patient diagnosed with SIH secondary to an anteriorly positioned thoracic osteophyte with resultant dural disruption, who after multiple attempts at nonsurgical management developed bilateral subdural hematomas necessitating emergent surgical intervention. The patient underwent a unilateral posterior repair of his osteophyte with successful anterior decompression. At 36months follow up, the patient reported completely resolved headaches with no focal neurological deficits.We outline our posterior approach to repair of the dural defect and review the management algorithm for the treatment of patients with SIH. We also examine the current hypotheses as to the origin, pathophysiology, diagnosis and treatment of this syndrome.A posterior approach was utilized to repair the dural defect caused by an anterior thoracic osteophyte in a patient with severe SIH complicated by bilateral subdural hematomas. This approach minimizes morbidity compared to an anterior approach and allowed for removal of the osteophyte and repair of the dural defect.

    View details for DOI 10.1016/j.ijscr.2012.06.009

    View details for PubMedID 23108168

  • Biomechanical Comparison of Spinopelvic Reconstruction Techniques in the Setting of Total Sacrectomy SPINE Mindea, S. A., Chinthakunta, S., Moldavsky, M., Gudipally, M., Khalil, S. 2012; 37 (26): E1622-E1627


    An in vitro biomechanical study.To biomechanically test and evaluate 4 different methods of spinopelvic reconstruction techniques and determine the most biomechanically stable construct for stabilization of the spinopelvic junction after total sacrectomy.Total sacrectomy is necessary to treat a sacral tumor when it involves the S1 vertebra. Instrumentation and reconstruction of the lumbar spine and pelvis are required after total sacrectomy and can be achieved by various reconstruction techniques. Currently, the preferred method of spinopelvic fixation is controversial.Seven human cadaveric (L1-pelvis) specimens were evaluated in flexion-extension, lateral bending, and axial rotation in a total sacrectomy model. Test constructs included (1) intact; (2) double-rod, double iliac screw (DDS); (3) single-rod, single iliac screw (SSS); (4) double iliac screw (DIS) fixation; and (5) modified Galveston technique (MGT). A load control protocol with 7.0 Nm moments applied at a rate of 1.5°/s was used to establish range of motion values for each tested construct on a 6-df spine motion simulator. Data were analyzed and normalized to intact.All instrumented constructs offered significant stability in all loading conditions compared with the intact condition. Stability offered by different constructs in all loading conditions trended as follows: DDS>DIS>SSS>MGT. Overall, the DDS construct provided 55%, 43%, and 60% more stability than SSS, DIS, and MGT, respectively. This was significant in flexion-extension when compared with SSS and in all loading conditions when compared with MGT.In the setting of total sacrectomy, the double-rod double iliac screw method provided the most rigid fixation, followed by DIS fixation, single-rod single screw, and the MGT. In spinopelvic reconstruction, the use of double iliac screws is recommended compared with single iliac screw fixation techniques when treating unstable conditions caused by total sacrectomy.

    View details for DOI 10.1097/BRS.0b013e31827619d3

    View details for Web of Science ID 000312396300004

    View details for PubMedID 23038619

  • Intracranial hypotension producing reversible coma: a systematic review, including three new cases A review JOURNAL OF NEUROSURGERY Loya, J. J., Mindea, S. A., Yu, H., Venkatasubramanian, C., Chang, S. D., Burns, T. C. 2012; 117 (3): 615-628


    Intracranial hypotension is a disorder of CSF hypovolemia due to iatrogenic or spontaneous spinal CSF leakage. Rarely, positional headaches may progress to coma, with frequent misdiagnosis. The authors review reported cases of verified intracranial hypotension-associated coma, including 3 previously unpublished cases, totaling 29. Most patients presented with headache prior to neurological deterioration, with positional symptoms elicited in almost half. Eight patients had recently undergone a spinal procedure such as lumbar drainage. Diagnostic workup almost always began with a head CT scan. Subdural collections were present in 86%; however, intracranial hypotension was frequently unrecognized as the underlying cause. Twelve patients underwent one or more procedures to evacuate the collections, sometimes with transiently improved mental status. However, no patient experienced lasting neurological improvement after subdural fluid evacuation alone, and some deteriorated further. Intracranial hypotension was diagnosed in most patients via MRI studies, which were often obtained due to failure to improve after subdural hematoma (SDH) evacuation. Once the diagnosis of intracranial hypotension was made, placement of epidural blood patches was curative in 85% of patients. Twenty-seven patients (93%) experienced favorable outcomes after diagnosis and treatment; 1 patient died, and 1 patient had a morbid outcome secondary to duret hemorrhages. The literature review revealed that numerous additional patients with clinical histories consistent with intracranial hypotension but no radiological confirmation developed SDH following a spinal procedure. Several such patients experienced poor outcomes, and there were multiple deaths. To facilitate recognition of this treatable but potentially life-threatening condition, the authors propose criteria that should prompt intracranial hypotension workup in the comatose patient and present a stepwise management algorithm to guide the appropriate diagnosis and treatment of these patients.

    View details for DOI 10.3171/2012.4.JNS112030

    View details for Web of Science ID 000307627100031

    View details for PubMedID 22725982

  • Inclusion of Asymptomatic Degenerative Discs in a Two-Level Anterior Cervical Discectomy and Fusion: A Decision Analysis WORLD NEUROSURGERY Boakye, M., Mindea, S. 2012; 78 (3-4): 339-343


    To perform a decision analysis model to compare single-level fusion versus two-level fusion in patients with an asymptomatic disc adjacent to a symptomatic disc.Probabilities and utilities of alternative outcomes in the decision tree were assigned based on systematic review of the literature and expert opinion. Rollback analysis determined the optimal treatment. Sensitivity analyses and Monte Carlo simulations were performed to identify effects of varying model parameters.Rollback analysis provided expected values of 0.92 versus 0.84 in favor of observation as the optimal decision. Sensitivity analysis identified the probability of developing adjacent segment disease (ASD) and the likelihood of surgery given a diagnosis of ASD as the most critical parameters influencing the decision. Observation was the preferred strategy at all values of probability of ASD < 100%. At a probability of ASD of 100%, fusion was the preferred strategy only when the probability of surgery for ASD was ? 66% or the utility assigned to successful nonoperative management was ? 0.84.Observation was the preferred strategy for management of asymptomatic adjacent degenerative discs (AADDs) given the probabilities and utilities used in the decision analysis model. The study was limited by unavailability of precise estimates of the probability of development of ASD and the probability of surgery after diagnosis of ASD, the most critical factors influencing the decision. However, the conclusions were robust given wide ranges used for these parameters in the sensitivity analysis.

    View details for DOI 10.1016/j.wneu.2011.11.035

    View details for Web of Science ID 000309908100036

    View details for PubMedID 22381313

  • International Spine Radiosurgery Consortium Consensus Guidelines for Target Volume Definition in Spinal Stereotactic Radiosurgery INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS Cox, B. W., Spratt, D. E., Lovelock, M., Bilsky, M. H., Lis, E., Ryu, S., Sheehan, J., Gerszten, P. C., Chang, E., Gibbs, I., Soltys, S., Sahgal, A., Deasy, J., Flickinger, J., Quader, M., Mindea, S., Yamada, Y. 2012; 83 (5): E597-E605


    Spinal stereotactic radiosurgery (SRS) is increasingly used to manage spinal metastases. However, target volume definition varies considerably and no consensus target volume guidelines exist. This study proposes consensus target volume definitions using common scenarios in metastatic spine radiosurgery.Seven radiation oncologists and 3 neurological surgeons with spinal radiosurgery expertise independently contoured target and critical normal structures for 10 cases representing common scenarios in metastatic spine radiosurgery. Each set of volumes was imported into the Computational Environment for Radiotherapy Research. Quantitative analysis was performed using an expectation maximization algorithm for Simultaneous Truth and Performance Level Estimation (STAPLE) with kappa statistics calculating agreement between physicians. Optimized confidence level consensus contours were identified using histogram agreement analysis and characterized to create target volume definition guidelines.Mean STAPLE agreement sensitivity and specificity was 0.76 (range, 0.67-0.84) and 0.97 (range, 0.94-0.99), respectively, for gross tumor volume (GTV) and 0.79 (range, 0.66-0.91) and 0.96 (range, 0.92-0.98), respectively, for clinical target volume (CTV). Mean kappa agreement was 0.65 (range, 0.54-0.79) for GTV and 0.64 (range, 0.54-0.82) for CTV (P<.01 for GTV and CTV in all cases). STAPLE histogram agreement analysis identified optimal consensus contours (80% confidence limit). Consensus recommendations include that the CTV should include abnormal marrow signal suspicious for microscopic invasion and an adjacent normal bony expansion to account for subclinical tumor spread in the marrow space. No epidural CTV expansion is recommended without epidural disease, and circumferential CTVs encircling the cord should be used only when the vertebral body, bilateral pedicles/lamina, and spinous process are all involved or there is extensive metastatic disease along the circumference of the epidural space.This report provides consensus guidelines for target volume definition for spinal metastases receiving upfront SRS in common clinical situations.

    View details for DOI 10.1016/j.ijrobp.2012.03.009

    View details for Web of Science ID 000306128100006

    View details for PubMedID 22608954

  • Arachnoid ossificans containing metaplastic hematopoietic marrow resulting in diffuse thoracic intrathecal cysts and severe myelopathy. European spine journal Abrams, J., Li, G., Mindea, S. A., Haynes, C. M., Cheng, I. 2012; 21: S436-40


    To present a rare case of multiple compressive thoracic intradural cysts with pathologic arachnoid ossification, review the literature and present the surgical options. Few reports have identified the existence of arachnoid calcifications and intrathecal cysts causing progressive myelopathy. The literature regarding each of these pathologies is limited to case reports. Their clinical significance is not well studied, although known to cause neurologic sequelae.An 81-year-old female clinically presents with rapidly progressive myelopathy. Pre-operative magnetic resonance imaging identified multiple compressive thoracic intrathecal cysts. Surgical exploration and decompression of these cysts identified calcified plaques within the arachnoid. Histopathologic examination revealed fibrocalcific tissue undergoing ossification with bone marrow elements.Due to progressive myelopathy, the thoracic cysts were decompressed and calcified plaques were excised, once identified intra-operatively.On last examination, the patient's neurologic status had not improved, but had stabilized. The rate of neurologic improvement from excision and decompression is variable, but it may still be warranted in the face of progressive neurologic deficits.

    View details for DOI 10.1007/s00586-011-2005-1

    View details for PubMedID 21892775

  • Morbidity and Mortality of C2 Fractures in the Elderly: Surgery and Conservative Treatment NEUROSURGERY Chen, Y., Boakye, M., Arrigo, R. T., Kalanithi, P. S., Cheng, I., Alamin, T., Carragee, E. J., Mindea, S. A., Park, J. 2012; 70 (5): 1055-1059


    Closed C2 fractures commonly occur after falls or other trauma in the elderly and are associated with significant morbidity and mortality. Controversy exists as to best treatment practices for these patients.To compare outcomes for elderly patients with closed C2 fractures by treatment modality.We retrospectively reviewed 28 surgically and 28 nonsurgically treated cases of closed C2 fractures without spinal cord injury in patients aged 65 years of age or older treated at Stanford Hospital between January 2000 and July 2010. Comorbidities, fracture characteristics, and treatment details were recorded; primary outcomes were 30-day mortality and complication rates; secondary outcomes were length of hospital stay and long-term survival.Surgically treated patients tended to have more severe fractures with larger displacement. Charlson comorbidity scores were similar in both groups. Thirty-day mortality was 3.6% in the surgical group and 7.1% in the nonsurgical group, and the 30-day complication rates were 17.9% and 25.0%, respectively; these differences were not statistically significant. Surgical patients had significantly longer lengths of hospital stay than nonsurgical patients (11.8 days vs 4.4 days). Long-term median survival was not significantly different between groups.The 30-day mortality and complication rates in surgically and nonsurgically treated patients were comparable. Elderly patients faced relatively high morbidity and mortality regardless of treatment modality; thus, age alone does not appear to be a contraindication to surgical fixation of C2 fractures.

    View details for DOI 10.1227/NEU.0b013e3182446742

    View details for Web of Science ID 000303390400013

    View details for PubMedID 22157549

  • Charlson Score is a Robust Predictor of 30-Day Complications Following Spinal Metastasis Surgery SPINE Arrigo, R. T., Kalanithi, P., Cheng, I., Alamin, T., Carragee, E. J., Mindea, S. A., Boakye, M., Park, J. 2011; 36 (19): E1274-E1280


    Retrospective chart review.To identify predictors of 30-day complications after the surgical treatment of spinal metastasis.Surgical treatment of spinal metastasis is considered palliative with the aim of reducing or delaying neurologic deficit. Postoperative complication rates as high as 39% have been reported in the literature. Complications may impact patient quality of life and increase costs; therefore, an understanding of which preoperative variables best predict 30-day complications will help risk-stratify patients and guide therapeutic decision making and informed consent.We retrospectively reviewed 200 cases of spinal metastasis surgically treated at Stanford Hospital between 1999 and 2009. Multiple logistic regression was performed to determine which preoperative variables were independent predictors of 30-day complications.Sixty-eight patients (34%) experienced one or more complications within 30 days of surgery. The most common complications were respiratory failure, venous thromboembolism, and pneumonia. On multivariate analysis, Charlson Comorbidity Index score was the most significant predictor of 30-day complications. Patients with a Charlson score of two or greater had over five times the odds of a 30-day complication as patients with a score of zero or one.After adjusting for demographic, oncologic, neurologic, operative, and health factors, Charlson score was the most robust predictor of 30-day complications. A Charlson score of two or greater should be considered a surgical risk factor for 30-day complications, and should be used to risk-stratify surgical candidates. If complications are anticipated, medical staff can prepare in advance, for instance, scheduling aggressive ICU care to monitor for and treat complications. Finally, Charlson score should be controlled for in future spinal metastasis outcomes studies and compared to other comorbidity assessment tools.

    View details for DOI 10.1097/BRS.0b013e318206cda3

    View details for Web of Science ID 000294207500005

    View details for PubMedID 21358481

  • Biomechanical Evaluations of Various C1-C2 Posterior Fixation Techniques SPINE Sim, H. B., Lee, J. W., Park, J. T., Mindea, S. A., Lim, J., Park, J. 2011; 36 (6): E401-E407


    A biomechanical in vitro study using human cadaveric spine.To compare the biomechanical stability of pedicle screws versus various established posterior atlantoaxial fixations used to manage atlantoaxial instability.Rigid screw fixation of the atlantoaxial complex provides immediate stability and excellent fusion success though has a high risk of neurovascular complications. Some spine surgeons thus insert shorter C2 pedicle or pars/isthmus screws as alternatives to minimize the latter risks. The biomechanical consequences of short pedicle screw fixation remain unclear, however.Seven human cadaveric cervical spines with the occiput attached (C0-C3) had neutral zone (NZ) and range of motion (ROM) evaluated in three modes of loading. Specimens were tested in the following sequence: initially (1) the intact specimens were tested, after destabilization of C1-C2, then the specimens underwent (2) C1 lateral mass and C2 short pedicle screw fixation (PS-S), (3) C1 lateral mass and C2 long pedicle screw fixation (PS-L), (4) C1 lateral mass and C2 intralaminar screw fixation (ILS), (5) Sonntag's modified Gallie fixation (MG) and (6) C1-C2 transarticular screw fixation with posterior wiring (TAS 1 MG). (7) The destabilized spine was also tested.All instrumented groups were significantly stiffer in NZ and ROM than the intact spines, except in lateral bending, which was statistically significantly increased in the TAS 1 MG group. The MG group's NZ and ROM values were statistically significantly weaker than those of the PS-S, PS-L, and the ROM values of the TAS 1 MG groups. The ILS group's NZ values were higher than those of the TAS 1 MG group and for ROM, than that of the PS-S and PS-L groups. In flexion, the NZ and ROM values of the TAS 1 MG group were significantly less than those of the PS-S, PS-L, ILS, and MG groups. In axial rotation, the NZ and ROM values of the MG group were statistically significantly higher than those of the PS-S, PS-L, ISL and TAS 1 MG groups.The TAS 1 MG procedures provided the highest stability. The MG method alone may not be adequate for atlantoaxial arthrodesis, because it does not provide sufficient stability in lateral bending and rotation modes. The C2 pedicle screw and C2 ILS techniques are biomechanically less stable than the TAS 1 MG. In the C1 lateral mass-C2 pedicle screw fixation, the use of a short pedicle screw may be an alternative when other screw fixation techniques are not feasible.

    View details for DOI 10.1097/BRS.0b013e31820611ba

    View details for Web of Science ID 000288005700005

    View details for PubMedID 21372651

  • Predictors of Survival After Surgical Treatment of Spinal Metastasis NEUROSURGERY Arrigo, R. T., Kalanithi, P., Cheng, I., Alamin, T., Carragee, E. J., Mindea, S. A., Park, J., Boakye, M. 2011; 68 (3): 674-681


    Surgery for spinal metastasis is a palliative treatment aimed at improving patient quality of life by alleviating pain and reversing or delaying neurologic dysfunction, but with a mean survival time of less than 1 year and significant complication rates, appropriate patient selection is crucial.To identify the most significant prognostic variables of survival after surgery for spinal metastasis.Chart review was performed on 200 surgically treated spinal metastasis patients at Stanford Hospital between 1999 and 2009. Survival analysis was performed and variables entered into a Cox proportional hazards model to determine their significance.Median overall survival was 8.0 months, with a 30-day mortality rate of 3.0% and a 30-day complication rate of 34.0%. A Cox proportional hazards model showed radiosensitivity of the tumor (hazard ratio: 2.557, P<.001), preoperative ambulatory status (hazard ratio: 2.355, P=.0001), and Charlson Comorbidity Index (hazard ratio: 2.955, P<.01) to be significant predictors of survival. Breast cancer had the best prognosis (median survival, 27.1 months), whereas gastrointestinal tumors had the worst (median survival, 2.66 months).We identified the Charlson Comorbidity Index score as one of the strongest predictors of survival after surgery for spinal metastasis. We confirmed previous findings that radiosensitivity of the tumor and ambulatory status are significant predictors of survival.

    View details for DOI 10.1227/NEU.0b013e318207780c

    View details for Web of Science ID 000287242300036

    View details for PubMedID 21311295

  • Recombinant Human Bone Morphogenetic Protein-2-Induced Radiculitis in Elective Minimally Invasive Transforaminal Lumbar Interbody Fusions A Series Review SPINE Mindea, S. A., Shih, P., Song, J. K. 2009; 34 (14): 1480-1484


    Retrospective single center analysis.The purpose of our study is to quantify the development of a postoperative radiculitis in our minimally invasive transforaminal lumbar interbody fusion patient population.The application of recombinant human Bone Morphogenetic Protein-2 (BMP) in spinal surgery has allowed for greater success in spinal fusions. This has led to the FDA approving its use in anterior lumbar interbody fusion. However, its well-recognized benefits have generated its "off-label" use in the cervical, thoracic, and lumbar spine. Despite its benefits, the adverse effects of its inflammatory properties are just starting to get recognized. Some clear adverse reactions have been documented in the literature in the cervical spine. However, we feel that these inflammatory properties may be present in the lumbar spine as well.We performed a retrospective chart review of 43 patients who had undergone a minimally invasive transforaminal lumbar interbody fusions. Thirty-five of these patients had BMP and 8 patients did not have BMP. We documented whether there was a preoperative radiculopathy present and whether a radiculopathy was present postoperative. We reviewed radiographic postoperative imaging to establish a structural cause for any radiculopathy. If new or increasing radicular symptoms were present, we attempted to assess the duration of these symptoms.Our analysis, showed that 0 of the 8 patients of the non-BMP group had new radicular symptoms that were not attributed to structural causes. In the BMP group, 4 of the 35 patients (11.4%) had new radicular symptoms without structural etiology.Our analysis suggest that patients undergoing minimally invasive transforaminal lumbar interbody fusions procedures have a higher incidence of developing new radicular symptoms that could be attributed to BMP.

    View details for DOI 10.1097/BRS.0b013e3181a396a1

    View details for Web of Science ID 000267112700009

    View details for PubMedID 19525840

  • Endovascular embolization of a recurrent cervical giant cell neoplasm using N-butyl 2-cyanoacrylate JOURNAL OF CLINICAL NEUROSCIENCE Mindea, S. A., Eddlerman, C. S., Hage, Z. A., Batjer, H. H., Ondra, S. L., Bendok, B. R. 2009; 16 (3): 452-454


    Pre-operative endovascular embolization of spinal giant cell tumors (GCTs) has been an effective strategy to reduce blood loss during surgical resection. Traditionally, spinal GCTs have been embolized with polyvinyl acetate (PVA) particles. We present the pre-operative embolization of a recurrent cervical GCT with N-butyl 2-cyanoacrylate (NBCA) rather than PVA. The patient was a 17-year-old female who, 3 months prior, had undergone a surgical resection of a cervical GCT without pre-operative embolization. She returned with tumor recurrence in the approximate location. Resection was recommended, and pre-operative embolization was requested. The tumor was embolized with NBCA. Post-embolization angiography demonstrated significantly decreased tumor "blush" and a significant reduction of the vascular supply. This is the first reported use of NBCA for the pre-operative embolization of a cervical GCT. The benefits of NBCA over PVA particles include superior penetration, permanent tumor embolization and lower exposure to radiation due to shorter procedure time.

    View details for DOI 10.1016/j.jocn.2008.03.017

    View details for Web of Science ID 000263762300020

    View details for PubMedID 19136261

  • The management of cranial injuries in antiquity and beyond. Neurosurgical focus Kshettry, V. R., Mindea, S. A., Batjer, H. H. 2007; 23 (1): E8-?


    Cranial injuries were among the earliest neurosurgical problems faced by ancient physicians and surgeons. In this review, the authors trace the development of neurosurgical theory and practice for the treatment of cranial injuries beginning from the earliest ancient evidence available to the collapse of the Greco-Roman civilizations. The earliest neurosurgical procedure was trephination, which modern scientists believe was used to treat skull fractures in some civilizations. The Egyptian papyri of Edwin Smith provide a thorough description of 27 head injuries with astute observations of clinical signs and symptoms, but little information on the treatment of these injuries. Hippocrates offered the first classification of skull fractures and discussion of which types required trephining, in addition to refining this technique. Hippocrates was also the first to understand the basis of increased intracranial pressure. After Hippocrates, the physicians of the Alexandrian school provided further insight into the clinical evaluation of patients with head trauma, including the rudiments of a Glasgow Coma Scale. Finally, Galen of Pergamon, a physician to fallen gladiators, substantially contributed to the understanding of the neuroanatomy and physiology. He also described his own classification system for skull fractures and further refined the surgical technique of trephination. From the study of these important ancient figures, it is clearly evident that the knowledge and experience gained from the management of cranial injuries has laid the foundation not only for how these injuries are managed today, but also for the development of the field of neurosurgery.

    View details for PubMedID 17961060

  • Diagnostic approach to Cushing disease. Neurosurgical focus Gross, B. A., Mindea, S. A., Pick, A. J., Chandler, J. P., Batjer, H. H. 2007; 23 (3): E1-?


    In Cushing disease, a pituitary corticotroph neoplasm causes secondary adrenal hypercortisolism. This condition has known morbidity and mortality, underscoring the need for an efficient and accurate diagnostic approach. An 11 p.m. salivary cortisol level is a modern, simple initial screening tool for the diagnosis of Cushing syndrome. Confirmation with a 24-hour urinary free cortisol test and/or a low-dose dexamethasone suppression test may subsequently be performed. Patients with repeatedly equivocal results should be reevaluated after several months or undergo a corticotropin-releasing hormone (CRH) stimulation test following low-dose dexamethasone suppression to help rule out pseudo-Cushing states. The presence of low morning serum adrenocorticotropic hormone (ACTH) levels then distinguishes primary adrenal hypercortisolism from Cushing disease and the ectopic ACTH syndrome. Patients with moderate ACTH levels can undergo CRH stimulation testing to clarify the underlying disease because those with an ACTH-independent disorder have blunted subsequent ACTH levels. Once ACTH-dependent hypercortisolemia is detected, magnetic resonance (MR) imaging of the pituitary gland can be performed to detect a pituitary neoplasm. Normal or equivocal MR imaging results revealing small pituitary lesions should be followed up with inferior petrosal sinus sampling, a highly specific measure for the diagnosis of Cushing disease in experienced hands. If necessary, body imaging may be used in turn to detect sources of ectopic ACTH.

    View details for PubMedID 17961030

  • Cervical spinal cord compression in chondrodysplasia punctata - Case illustration JOURNAL OF NEUROSURGERY Yang, B. P., Mindea, S. A., DiPatri, A. J. 2006; 104 (3): 212-212

    View details for Web of Science ID 000236400300013

    View details for PubMedID 16572643

  • Endovascular treatment strategies for cerebral vasospasm. Neurosurgical focus Mindea, S. A., Yang, B. P., Bendok, B. R., Miller, J. W., Batjer, H. H. 2006; 21 (3): E13-?


    Cerebral vasospasm is a significant cause of morbidity and mortality in patients who have sustained a subarachnoid hemorrhage from aneurysm rupture. Symptomatic cerebral vasospasm is also a strong predictor of poor clinical outcome and has thus drawn a great deal of interest from cerebrovascular surgeons. Although medical management is the cornerstone of treatment for this condition, endovascular intervention may be warranted for those in whom this treatment fails and in whom symptomatic vasospasm subsequently develops. The rapid advancements in endovascular techniques and pharmacological agents used to combat this pathological state continue to offer promise in broadening the available treatment armamentarium. In this article the authors discuss the rationale and basis for using the various endovascular options for the treatment of cerebral vasospasm, and they also discuss the limitations, complications, and efficacy of these treatment strategies in regard to neurological condition and outcome.

    View details for PubMedID 17029337

  • Pituitary apoplexy PEDIATRIC RADIOLOGY Yang, B. P., Yang, C. W., Mindea, S. A., Tomita, T. 2005; 35 (8): 830-831

    View details for DOI 10.1007/s00247-005-1460-4

    View details for Web of Science ID 000230809300017

    View details for PubMedID 15864575

  • Reduplication of ventriculoperitoneal shunt catheter tip back through shunt tract PEDIATRIC NEUROSURGERY Yang, B. P., Yang, C. W., Mindea, S. A., Alden, T. D. 2005; 41 (3): 168-169

    View details for DOI 10.1159/000085879

    View details for Web of Science ID 000230306300013

    View details for PubMedID 15995339

  • Surgical management of a ruptured posterior choroidal intraventricular aneurysm associated with moyamoya disease using nameless stereotaxy: Case report and review of the literature NEUROSURGERY Ali, M. L., Bendok, B. R., Getch, C. C., Gottardi-Littell, N. R., Mindea, S., Batjer, H. H. 2004; 54 (4): 1019-1024


    Prevention of rebleeding is the most important aspect of the management of hemorrhagic moyamoya disease, because rebleeding causes significant morbidity and mortality.A 26-year-old male patient with a history of moyamoya disease since the age of 3 years and multiple strokes was in a semicomatose state at presentation. He was found to have intraventricular and periventricular hemorrhages abutting the atrium of the right ventricle. His hospital course was complicated by a second hemorrhage. Both bleeding events were believed to be secondary to a ruptured right lateral posterior choroidal aneurysm.The aneurysm was excised and revealed histopathology consistent with a true saccular aneurysm. Frameless stereotactic guidance was used during surgery to minimize damage to collateral vessels and to shorten the surgical corridor.The management of hemorrhagic moyamoya disease should be modified based on the source of hemorrhage and its relation to a specifically located aneurysm. In the case of aneurysms arising from the choroidal artery, the general belief is that most of these represent pseudoaneurysms and have a tendency to regress spontaneously. Because of the rebleeding risk, we recommend early intervention in treating ruptured intracranial aneurysms using the least invasive surgical techniques.

    View details for Web of Science ID 000220769100060

    View details for PubMedID 15046673

  • Selective cerebral revascularization as an adjunct in the treatment of giant anterior circulation aneurysms. Neurosurgical focus O'Shaughnessy, B. A., Salehi, S. A., Mindea, S. A., Batjer, H. H. 2003; 14 (3)


    Cerebral revascularization, an indispensable component of neurovascular surgery, has been performed in the treatment of cranial base tumors, complex cerebral aneurysms, and occlusive cerebrovascular disease. The goal of a revascularization procedure is to augment blood flow distally. It can therefore be used as an adjunctive measure in the treatment of complex neurosurgical disease processes that require parent artery sacrifice for definitive treatment. In the treatment of giant anterior circulation aneurysms, for instance, a cerebral revascularization procedure may be considered in patients in whom the collateral circulation is marginal and in whom lesions may be treated either using a Hunterian-based strategy or clip-assisted reconstruction requiring a prolonged period of temporary occlusion. To date, there is no entirely effective method known to produce long-term tolerance to carotid artery (CA) sacrifice and, largely for that reason, some neurovascular surgeons advocate universal revascularization. The authors of this report, however, prefer to perform revascularization only in the limited subset of patients in whom preoperative assessment has revealed risk factors for cerebral ischemia due to hypoperfusion. In this paper, the authors introduce their protocol for assessing cerebrovascular reserve capacity, indications for cerebral revascularization in the treatment of complex anterior circulation aneurysms, and discuss their rationale for choosing to practice selective, rather than universal, revascularization.

    View details for PubMedID 15709721

Stanford Medicine Resources: