Iman Feiz-Erfan

The University of Arizona, Tucson, Arizona, United States

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Publications (84)192.58 Total impact

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    ABSTRACT: Large cranial defects represent reconstructive challenges. Polyetheretherketone (PEEK) implants are preoperatively tailored to the exact size of the defect and exhibit an excellent combination of strength, durability, and environmental resistance. This study presents our experience with patient-specific PEEK implants with computer modeling. A retrospective chart review was conducted on all patients who underwent cranioplasty treated by a PEEK implant between 2007 and 2012. Analysis of the preoperative and perioperative data as well as outcome analysis was performed. A total of 11 patients were included. Mean age was 46 years. The indication for cranioplasty was bone flap infection and subsequent removal in 8 patients, traumatic bone loss in 2 patients, and acquired defect due to cancer resection in 1 patient. The mean time to PEEK cranioplasty since the patient's last operation was 16 months. The mean defect size was 74 cm. The mean surgical blood loss was 124 mL. The mean length of stay was 3 days. Complications included 1 postoperative bleeding that required reoperation, but the PEEK implant was successfully salvaged. The mean time to follow-up was 6 months. Use of patient-specific PEEK implants is a good alternative for alloplastic cranioplasty. It is associated with low morbidity as reported in our series, with additional advantages including strength, stiffness, durability, and inertness. It would be beneficial to assess the longer-term outcomes; however, it appears at first glance that PEEK implants show great promise in calvarial reconstruction.
    The Journal of craniofacial surgery 04/2015; 26(3). DOI:10.1097/SCS.0000000000001413 · 0.68 Impact Factor
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    ABSTRACT: Microcystic meningioma is a rare tumor with myxoid and microcystic features. Our objective was to evaluate the efficacy of surgical resection of microcystic meningioma. Between December 1985 and October 2000 we treated 25 microcystic meningioma patients with surgical resection. We retrospectively analyzed the results including the long-term follow-up of this patient population. We identified 15 women and 10 men with a mean age of 53.8years (24-76years) who had microcystic meningiomas treated with surgery. Based on the Simpson grade, we found four Grade I (16%), 16 Grade II (64%), three Grade III (12%) and two Grade IV (8%) resections. The mean preoperative Karnofsky Performance Scale (KPS) score was 80.3 (range 60-100). The mean postoperative KPS score was 90.4 (range 60-100). At a mean follow-up of 101.7months (range 16-221) the KPS score improved to a mean of 93.8. The recurrence/progression free survival (RFS/PFS) rates at 3 and 5years were 96% and 88%, respectively. The 3 and 5year RFS/PFS rates based on the Simpson grade were evaluated. The 3year RFS/PFS rates for Grade I, II, III and IV were 100%, 100%, 66.6% and 100%, respectively. The 5year RFS/PFS rates were 66.6%, 90%, 66.6% and 100%, respectively. Microcystic meningioma is a rare tumor, which is characterized by extracellular microcystic spaces filled by edematous fluid and peritumoral edema. Following surgical resection these tumors have a positive prognosis with a benign course. The surgical outcomes seem to be associated with the risks related to the surgical procedure. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Journal of Clinical Neuroscience 02/2015; 22(4). DOI:10.1016/j.jocn.2014.12.004 · 1.32 Impact Factor
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    ABSTRACT: A 22-month-old girl presented with neck pain and stiffness and magnetic resonance imaging showed an extradural mass extending from C2 through the C4 level with moderate to severe compression of the cord. A left unilateral C2-C4 laminectomy was performed revealing an extradural rubbery tumor; a small biopsy was obtained. Examination of stained tissue revealed the presence of a parasitic worm that was identified as a gravid female Onchocerca lupi. A magnetic resonance imaging at 7 weeks follow-up showed a significantly decreased size of the enhancing lesion and the patient's symptoms gradually resolved. This is the first report of zoonotic O. lupi in the United States. The parasite has been reported in dogs and cats in the western United States, and from people in four cases reported from Europe. A great deal more needs to be learned, including full host range and geographic distribution, before we fully understand O. lupi infections in animals and man.
    The American journal of tropical medicine and hygiene 02/2013; 88(3). DOI:10.4269/ajtmh.12-0733 · 2.74 Impact Factor
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    ABSTRACT: Object Resection of cancer and the involved artery in the neck has been applied with some success, but the indications for such an aggressive approach at the skull base are less well defined. The authors therefore evaluated the outcomes of advanced skull base malignancies in patients who were treated with bypass and resection of the internal carotid artery (ICA). Methods The authors retrospectively reviewed the charts of all patients with advanced head and neck cancers who underwent ICA sacrifice with revascularization in which an extracranial-intracranial bypass was used between 1995 and 2010 at the Barrow Neurological Institute. Results Eighteen patients (11 male and 7 female patients; mean age 46 years, range 7-69 years) were identified. There were 4 sarcomas and 14 carcinomas that involved the ICA at the skull base. All patients underwent ICA sacrifice with revascularization. One patient died of a stroke after revascularization. A second patient died of the effects of a fistula between the oral and cranial cavities (surgery-related mortality rate 11.1%). Eight months after the operation, 1 patient developed occlusion of the bypass and died. Complications associated with the bypass surgery included 1 case of subdural hematoma (SDH) with blindness, 1 case of status epilepticus, and 1 case of asymptomatic bypass occlusion (bypass-related morbidity 16.7%). Complications associated with tumor resection included 3 cases of CSF leakage requiring repair and shunting, 1 case of hydrocephalus requiring shunting, 1 case of SDH, and 1 case of contralateral ICA injury requiring a bypass (tumor resection morbidity rate 33.3%). In 1 patient treated with adjuvant therapy before surgery, the authors identified only a radiation effect and no tumor on resection. In a second patient the bypass was occluded, and her tumor was not resected. The other 16 patients underwent gross-total resection of their tumor. Excluding the surgery-related deaths, the mean and median lengths of survival in this series were 13.2 and 8.3 months, respectively (range 1.5-48 months). Including the surgery-related deaths, the mean and median lengths of survival were 11.8 and 8 months, respectively (range 17 days-48 months). At last follow-up all patients had died of cancer or cancer-related causes. Conclusions Despite maximal surgical intervention, including ICA sacrifice at the skull base with revascularization, patient survival was dismal, and the complication rate was significant. The authors no longer advocate such an aggressive approach in this patient population. On rare occasions, however, such an approach may be considered for low-grade malignancies.
    Journal of Neurosurgery 10/2012; 118(3). DOI:10.3171/2012.9.JNS12332 · 3.15 Impact Factor
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    ABSTRACT: Object Hematogenous metastases to the sacrum can produce significant pain and lead to spinal instability. The object of this study was to evaluate the palliative benefit of surgery in patients with these metastases. Methods The authors retrospectively reviewed all cases involving patients undergoing surgery for metastatic disease to the sacrum at a single tertiary cancer center between 1993 and 2005. Results Twenty-five patients (21 men, 4 women) were identified as having undergone sacral surgery for hematogenous metastatic disease during the study period. Their median age was 57 years (range 25-71 years). The indications for surgery included palliation of pain (in 24 cases), need for diagnosis (in 1 case), and spinal instability (in 3 cases). The most common primary disease was renal cell carcinoma. Complications occurred in 10 patients (40%). The median overall survival was 11 months (95% CI 5.4-16.6 months). The median time from the initial diagnosis to the diagnosis of metastatic disease in the sacrum was 14 months (95% CI 0.0-29.3 months). The numerical pain scores (scale 0-10) were improved from a median of 8 preoperatively to a median of 3 postoperatively at 90 days, 6 months, and 1 year (p < 0.01). Postoperative modified Frankel grades improved in 8 cases, worsened in 3 (due to disease progression), and remained unchanged in 14 (p = 0.19). Among patients with renal cell carcinoma, the median overall survival was better in those in whom the sacrum was the sole site of metastatic disease than in those with multiple sites of metastatic disease (16 vs 9 months, respectively; p = 0.053). Conclusions Surgery is effective to palliate pain with acceptable morbidity in patients with metastatic disease to the sacrum. In the subgroup of patients with renal cell carcinoma, those with the sacrum as their solitary site of metastatic disease demonstrated improved survival.
    Journal of neurosurgery. Spine 08/2012; 17(4):285-91. DOI:10.3171/2012.7.SPINE09351 · 2.36 Impact Factor
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    ABSTRACT: It has been suggested that specific cervical spine fractures (CSfx) (location at upper cervical spine [CS], subluxation, or involvement of the transverse foramen) are predictive of blunt cerebrovascular injury (BCVI). We sought to determine the incidence of BCVI with CSfx in the absence of high-risk injury patterns. We performed a retrospective study in patients with CSfx who underwent evaluation for BCVI. The presence of recognized CS risk factors for BCVI and other risk factors (Glasgow coma score ≤ 8, skull-based fracture, complex facial fractures, soft-tissue neck injury) were reviewed. Patients were divided into 2 groups based on the presence/absence of risk factors. A total of 260 patients had CSfx. When screened for high-risk pattern of injury for BCVI, 168 patients were identified and 13 had a BCVI (8%). The remaining 92 patients had isolated low CSfx (C4-C7) without other risk factors for BCVI. In this group, 2 patients were diagnosed with BCVI (2%). Failure to screen all patients with CSfx would have missed 2 of 15 BCVIs (13%). We propose that all CS fracture patterns warrant screening for BCVI.
    American journal of surgery 12/2011; 202(6):684-8; discussion 688-9. DOI:10.1016/j.amjsurg.2011.06.033 · 2.41 Impact Factor
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    ABSTRACT: Eastern Association for the Surgery of Trauma guideline for the evaluation of blunt cerebrovascular injury (BCVI) states that pediatric trauma patients should be evaluated using the same criteria as the adult population. The purpose of our study was to determine whether adult criteria translate to the pediatric population. Retrospective evaluation was performed at a Level I trauma center of blunt pediatric trauma patients (age <15 years) presenting over a 5-year period. Data obtained included patient demographics, presence of adult risk factors for BCVI (Glasgow coma scale ≤8, skull base fracture, cervical spine fracture, complex facial fractures, and soft tissue injury to the neck), presence of signs/symptoms of BCVI, method of evaluation, treatment, and outcome. A total of 1,209 pediatric trauma patients were admitted during the study period. While 128 patients met criteria on retrospective review for evaluation based on Eastern Association for the Surgery of Trauma criteria, only 52 patients (42%) received subsequent radiographic evaluation. In all, 14 carotid artery or vertebral artery injuries were identified in 11 patients (all admissions, 0.9% incidence; all screened, 21% incidence). Adult risk factors were present in 91% of patients diagnosed with an injury. Major thoracic injury was found in 67% of patients with carotid artery injuries. Cervical spine fracture was found in 100% of patients with vertebral artery injuries. Stroke occurred in four patients (36%). Stroke rate after admission for untreated patients was 38% (3/8) versus 0.0% in those treated (0/2). Mortality was 27% because of concomitant severe traumatic brain injury. Risk factors for BCVI in the pediatric trauma patient appear to mimic those of the adult patient.
    The Journal of trauma 09/2011; 71(3):559-64; discussion 564. DOI:10.1097/TA.0b013e318226eadd · 2.96 Impact Factor
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    ABSTRACT: Craniofacial approaches provide excellent exposure to lesions in the anterior and middle cranial fossae. The authors review their experience with craniofacial approaches for resection of large juvenile nasopharyngeal angiofibromas. Between 1992 and 2009, 22 patients (all male, mean age 15 years, range 9-27 years) underwent 30 procedures. These cases were reviewed retrospectively. Gross-total resection of 17 (77%) of the 22 lesions was achieved. The average duration of hospitalization was 8.2 days (range 3-20 days). The rate of recurrence and/or progression was 4 (18%) of 22, with recurrences occurring a mean of 21 months after the first resection. All patients underwent preoperative embolization. Nine patients (41%) developed complications, the most common of which was CSF leakage (23%). The average follow-up was 27.7 months (range 2-144 months). The surgery-related mortality rate was 0%. Based on their mean preoperative (90) and postoperative (90) Karnofsky Performance Scale scores, 100% of patients improved or remained the same. The authors' experience shows that craniofacial approaches provide an excellent avenue for the resection of large juvenile nasopharyngeal angiofibromas, with acceptable rates of morbidity and no deaths.
    Journal of Neurosurgery Pediatrics 07/2011; 8(1):71-8. DOI:10.3171/2011.4.PEDS10514 · 1.37 Impact Factor
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    ABSTRACT: Resection of tumors of the third ventricle via the anterior interhemispheric transcallosal approach represents a surgical challenge. It carries a risk of postoperative complications, due to the role of surrounding structures in control of eloquent functions. We reviewed the immediate morbidity and mortality associated with this approach. Between June 1993 and July 2007, 38 patients underwent resection of tumors of the third ventricle via the anterior interhemispheric transcallosal approach at The University of Texas M. D. Anderson Cancer Center. Their 30-day postoperative morbidity and mortality rates were retrospectively analyzed relative to clinical variables possibly affecting these rates. Complications were categorized as neurological, regional, and systemic and were subclassified as major or minor. The overall complication rate was 50%. Major complications occurred in 37% of patients; 34% suffered neurological complications (16% being major complications). Surgical mortality was 8%. Univariate analysis demonstrated that tumor hemorrhage (p=0.04), preoperative Karnofsky Performance Scale (KPS) score (p=0.04), tumor status (recurrent versus [vs.] new or residual; p=0.01), and cauterization of any of the bridging veins (p=0.04) were associated with the incidence of postoperative complications. Multivariate analysis showed that increased age at surgery (p=0.04), tumor status (p=0.03), preoperative KPS score (p=0.02), and the extent of tumor resection (p=0.05) correlated significantly with the incidence of postoperative complications. Resection of tumors of the third ventricle via the interhemispheric transcallosal approach is associated with significant postoperative morbidity. Preserving the venous structures is of paramount importance in minimizing major neurological complications. Our results have practical risk-predictive value and can serve as the foundation for subsequent outcome studies.
    Journal of Clinical Neuroscience 07/2010; 17(7):830-6. DOI:10.1016/j.jocn.2009.12.007 · 1.32 Impact Factor
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    ABSTRACT: The aim of this study was to describe quantitatively the properties of the posterolateral approaches and their combination. Six silicone-injected cadaveric heads were dissected bilaterally. Quantitative data were generated with the Optotrak 3020 system (Northern Digital, Waterloo, Canada) and Surgiscope (Elekta Instruments, Inc., Atlanta, GA), including key anatomic points on the skull base and brainstem. All parameters were measured after the basic retrosigmoid craniectomy and then after combination with a basic far-lateral extension. The clinical results of 20 patients who underwent a combined retrosigmoid and far-lateral approach were reviewed. The change in accessibility to the lower clivus was greatest after the far-lateral extension (mean change, 43.62 +/- 10.98 mm2; P = .001). Accessibility to the constant landmarks, Meckel's cave, internal auditory meatus, and jugular foramen did not change significantly between the 2 approaches (P > .05). The greatest change in accessibility to soft tissue between the 2 approaches was to the lower brainstem (mean change, 33.88 +/- 5.25 mm2; P = .0001). Total removal was achieved in 75% of the cases. The average postoperative Glasgow Outcome Scale score of patients who underwent the combined retrosigmoid and far-lateral approach improved significantly, compared with the preoperative scores. The combination of the far-lateral and simple retrosigmoid approaches significantly increases the petroclival working area and access to the cranial nerves. However, risk of injury to neurovascular structures and time needed to extend the craniotomy must be weighed against the increased working area and angles of attack.
    Neurosurgery 03/2010; 66(3 Suppl Operative):54-64. DOI:10.1227/01.NEU.0000354366.48105.FE · 3.03 Impact Factor
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    ABSTRACT: Adjuvant whole-brain radiation therapy (WBRT) after resection of single brain metastases remains controversial. Despite a phase III trial to the contrary, clinicians often withhold WBRT after resection of single brain metastases based on the argument that available evidence does not inform regarding treatment of all patients, such as those with radioresistant tumors. However, there is limited information about whether subpopulations benefit equally from WBRT after resection. Therefore, we undertook a retrospective study to determine the clinical, radiographic, and histologic features that influenced the effectiveness of adjuvant WBRT. We reviewed 358 patients with newly diagnosed, single brain metastases, who underwent resection, of which 142 (40%) received adjuvant WBRT and 216 (60%) did not. Median follow-up was 60.1 months. There were multiple tumor histologies, including 197 (55%) "radiosensitive" and 161 (45%) "radioresistant" tumors. Compared with observation, WBRT significantly reduced recurrence both locally (HR = 0.58; 95% CI 0.35-0.98, P = .04) and at distant brain sites (HR = 0.43, 95% CI 0.30-0.61, P < .001). Multivariate analyses demonstrated that withholding WBRT was an independent predictor of local and distant recurrence. For local recurrence, tumors with a maximum diameter of ≥3 cm that did not receive adjuvant WBRT had an increased risk of recurring locally (HR = 3.14, 95% CI 1.02-9.69, P = .05). For distant recurrence, patients whose primary disease was progressing and who did not receive WBRT had an increased risk of distant recurrence (HR = 2.16, 95% CI 1.01-4.66, P = .05). There was no effect of WBRT based on tumor type. Adjuvant WBRT significantly reduces local and distant recurrences in subsets of patients, particularly those with metastases >3 cm or with active systemic disease.
    Neuro-Oncology 02/2010; 12(7):711-9. DOI:10.1093/neuonc/noq005 · 5.29 Impact Factor
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    ABSTRACT: We sought to quantitate the effect of extensions of transbasal approaches (TBAs) on midline and paramedian targets of the cranial base. Eight silicone-injected cadaveric heads were dissected with extensions of TBA level I removal of the orbital bar. Objective measures were the comparisons of the accessibility of midline and paramedian targets with progressive dissections by level II detachment of the medial canthal ligaments and removal of the nasal bone and by level III removal of the lateral orbital walls with lateral orbital retraction. Mean areas of freedom increased for most targets with progressive bone removal. For midline targets, the most effective freedom increment was at the pituitary gland (level II: 28.8%, p = 0.05; level III: 107.1%, p < 0.001). For paramedian targets, the best freedom increment was for the foramen rotundum (level II: 56.4%; level III: 134.5%, all p < 0.001). Extensions of the TBA can increase the surgical corridor to midline and paramedian structures, especially for pituitary and maxillary regions. Level II exposure offers no clear benefit for most targets except the foramen rotundum. With level III exposure, all targets are effectively exposed compared with levels I and II.
    Skull Base 11/2009; 19(6):387-99. DOI:10.1055/s-0029-1224773 · 0.66 Impact Factor
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    ABSTRACT: Nonpowder (ball-bearing and pellet) weapons derive their source of energy from compressed air or carbon dioxide. Such weapons are dangerous toys that cause serious injuries and even death to children and adolescents. A retrospective chart review study was undertaken to describe nonpowder gun injuries at a southwestern US urban level I adult and pediatric trauma center. Specific emphasis was placed on intracranial injuries. Over the past 6 years, a total of 29 pediatric and 7 adult patients were identified as having nonpowder firearm injuries. The patient population was overwhelmingly male (89.7%; mean age, 11 years). Overall, 17 out of 29 pediatric patients (56.8%) sustained serious injury. Nine patients (30.0%) required operation, 6 (20.7%) sustained significant morbidity, and there were 2 deaths (6.9%). Injuries to the brain, eye, head, and neck were the most common sites of injury (65.6%). Specific intracranial injuries in 3 pediatric patients are described that resulted in the death of 2 children. We suggest that age warning should be adjusted to 18 years or older for unsupervised use to be considered safe of these potentially lethal weapons.
    Pediatric Neurosurgery 07/2009; 45(3):205-9. DOI:10.1159/000222671 · 0.50 Impact Factor
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    ABSTRACT: Sarcomas of the spine are a challenging problem due to their frequent and extensive involvement of multiple spinal segments and high recurrence rates. Gross-total resection to negative margins, with preservation of neurological function and palliation of pain, is the surgical goal and may be achieved using either intralesional resection or en bloc excision. The authors report outcomes of surgery for primary and metastatic sarcomas of the mobile spine in a large patient series. A retrospective review of patients undergoing resection for sarcomas of the mobile spine between 1993 and 2005 was undertaken. Sarcomas were classified by histology study results and as either primary or metastatic. Details of the surgical approach, levels of involvement, and operative complications were recorded. Outcome measures included neurological function, palliation of pain, local recurrence, and overall survival. Eighty patients underwent 110 resections of either primary or metastatic sarcomas of the mobile spine. Twenty-nine lesions were primary sarcomas (36%) and 51 were metastatic sarcomas (64%). Intralesional resections were performed in 98 surgeries (89%) and en bloc resections were performed in 12 (11%). Median survival from surgery for all patients was 20.6 months. Median survival for patients with a primary sarcoma of the spine was 40.2 months and was 17.3 months for patients with a metastatic sarcoma. Predictors of improved survival included a chondrosarcoma histological type and a better preoperative functional status, whereas osteosarcoma and a high-grade tumor were negative influences on survival. Multivariate analysis showed that only a high-grade tumor was an independent predictor of shorter overall survival. American Spinal Injury Association scale grades were maintained or improved in 97% of patients postoperatively, and there was a significant decrease in pain scores postoperatively. No significant differences in survival or local recurrence rates between intralesional or en bloc resections for either primary or metastatic spine sarcomas were found. Surgery for primary or metastatic sarcoma of the spine is associated with an improvement in neurological function and palliation of pain. The results of this study show a significant difference in patient survival for primary versus metastatic spine sarcomas. The results do not show a statistically significant benefit in survival or local recurrence rates for en bloc versus intralesional resections for either metastatic or primary sarcomas of the spine, but this may be due to the small number of patients undergoing en bloc resections.
    Journal of Neurosurgery Spine 09/2008; 9(2):120-8. DOI:10.3171/SPI/2008/9/8/120 · 2.36 Impact Factor
  • Iman Feiz-Erfan · Eric M Horn · Robert F Spetzler
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    ABSTRACT: Lesions in the thalamomesencephalic junction can be reached via an anterolateral approach, interhemispheric approach, transcortical (parieto-occipital lobule) approach, subtemporal approach, supracerebellar approaches, or transsylvian-insular approach. We now describe a new approach, a transanterior perforating substance approach, to this territory. A 33-year-old man with progressive right arm tremors, mild hemiparesis, and a cavernous malformation of the thalamomesencephalic junction was followed for 5 years. Because of clinical progression, he underwent a left orbitozygomatic approach to the cavernous malformation, which could not be accessed because of a high-riding basilar artery. Hence, a new transsylvian corridor of exposure was developed using frameless neuronavigation. The trajectory, which was dorsal to M1, led through the perforating branches of M1. Care was taken to avoid violating any arterial perforators. To reach the lesion, a small opening into the brain was created near the optic tract. The cavernous malformation was resected totally. Postoperatively, the patient's tremors were cured. No visual deficits were encountered. Imaging showed a small ischemic stroke in the basal ganglia likely related to manipulation of a perforator. Initially, his hemiparesis worsened, but it improved significantly within 10 months with only a moderate decrease in strength. The transanterior perforating substance approach effectively allowed access to the thalamomesencephalic junction and was associated with significant morbidity. However, the safety of the approach needs further validation. Neuronavigation is indicated to choose the most direct trajectory through the M1 perforators. Tractography may help protect the optic tract.
    Neurosurgery 08/2008; 63(1 Suppl 1):ONS69-72; discussion ONS72. DOI:10.1227/01.neu.0000335014.75993.36 · 3.03 Impact Factor
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    ABSTRACT: The authors conducted a study to evaluate the clinical characteristics and surgical outcomes in patients with spinal schwannomas and without neurofibromatosis (NF). The data obtained in 128 patients who underwent resection of spinal schwannomas were analyzed. All cases with neurofibromas and those with a known diagnosis of NF Type 1 or 2 were excluded. Karnofsky Performance Scale (KPS) scores were used to compare patient outcomes when examining the anatomical location and spinal level of the tumor. The neurological outcome was further assessed using the Medical Research Council (MRC) muscle testing scale. Altogether, 131 schwannomas were treated in 128 patients (76 males and 52 females; mean age 47.7 years). The peak prevalence is seen between the 3rd and 6th decades. Pain was the most common presenting symptom. Gross-total resection was achieved in 127 (97.0%) of the 131 lesions. The nerve root had to be sacrificed in 34 cases and resulted in minor sensory deficits in 16 patients (12.5%) and slight motor weakness (MRC Grade 3/5) in 3 (2.3%). The KPS scores and MRC grades were significantly higher at the time of last follow-up in all patient groups (p = 0.001 and p = 0.005, respectively). Spinal schwannomas may occur at any level of the spinal axis and are most commonly intradural. The most frequent clinical presentation is pain. Most spinal schwannomas in non-NF cases can be resected totally without or with minor postoperative deficits. Preoperative autonomic dysfunction does not improve significantly after surgical management.
    Journal of Neurosurgery Spine 08/2008; 9(1):40-7. DOI:10.3171/SPI/2008/9/7/040 · 2.36 Impact Factor
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    ABSTRACT: We retrospectively reviewed our experience treating third ventricular colloid cysts to compare the efficacy of endoscopic and transcallosal approaches. Between September 1994 and March 2004, 55 patients underwent third ventricular colloid cyst resection. The transcallosal approach was used in 27 patients; the endoscopic approach was used in 28 patients. Age, sex, cyst diameter, and presence of hydrocephalus were similar between the two groups. The operating time and hospital stay were significantly longer in the transcallosal craniotomy group compared with the endoscopic group. Both approaches led to reoperations in three patients. The endoscopic group had two subsequent craniotomies for residual cysts and one repeat endoscopic procedure because of equipment malfunction. The transcallosal craniotomy group had two reoperations for fractured drainage catheters and one operation for epidural hematoma evacuation. The transcallosal craniotomy group had a higher rate of patients requiring a ventriculoperitoneal shunt (five versus two) and a higher infection rate (five versus none). Intermediate follow-up demonstrated more small residual cysts in the endoscopic group than in the transcallosal craniotomy group (seven versus one). Overall neurological outcomes, however, were similar in the two groups. Compared with transcallosal craniotomy, neuroendoscopy is a safe and effective approach for removal of colloid cysts in the third ventricle. The endoscope can be considered a first-line treatment for these lesions, with the understanding that a small number of these patients may need an open craniotomy to remove residual cysts.
    Neurosurgery 07/2008; 62(6 Suppl 3):1076-83. DOI:10.1227/01.neu.0000333773.43445.7b · 3.03 Impact Factor
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    ABSTRACT: We explored relevant regional microanatomy as it relates to the challenging anterior interforniceal (AIF) approach for removing hypothalamic hamartomas. Five silicone-injected cadaveric heads were dissected by use of frameless stereotactic navigation to reveal microanatomy and extent of exposure through the transcallosal AIF approach. Distances between trajectories to the coronal suture and the genu of the corpus callosum (CC) and between the posterior border of the anterior commissure to the lower end of the rostrum of the CC and posterior border of the foramen of Monro were measured. The AIF approach provided adequate access to the anterior third ventricle and related structures (i.e., hypothalamus, infundibular recess, and mamillary bodies) through the corridor bounded by the anterior commissure anteriorly and the choroid plexus at the foramen of Monro posteriorly. The mean distances from the posterior trajectory to the coronal suture and the genu of the CC were 44.8 mm (range, 43.8-46.2 mm) and 14.88 mm (14.1-15.7 mm), respectively. The mean distance from the anterior trajectory posterior to the coronal suture was 4.66 mm (0-8.9 mm), and 32.6 mm (30.5-33.9 mm) to the genu of the CC. The mean length of callosotomy was 17.52 mm (16.2-19.1 mm). The mean distance between the posterior border of the anterior commissure and the lower end of the rostrum of the CC was 5.22 mm (4.6-5.6 mm), and 10.52 mm (9.7-11.5 mm) to the posterior border of the foramen of Monro. The technically safe AIF approach permitted limited interforniceal splitting, no major deep vein manipulation, and adequate visualization of the hypothalamus, infundibular recess, and mamillary bodies.
    Neurosurgery 07/2008; 62(6 Suppl 3):1059-65. DOI:10.1227/01.neu.0000333771.58693.a4 · 3.03 Impact Factor
  • Iman Feiz-Erfan · Laurence D Rhines · Jeffrey S Weinberg
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    ABSTRACT: The role of surgery in the treatment of metastatic spinal tumors causing epidural compression traditionally consisted of posterior decompression. This procedure plus radiotherapy, however, could not be demonstrated to provide any benefit over radiotherapy alone, and surgery fell into disfavor in managing metastatic vertebral tumors. The advent of newer, more sophisticated approaches, along with improved spinal instrumentation and reconstruction techniques, which allowed direct decompression of neural elements and resection of the tumor, have revived the use of surgery in these tumors. These modern spinal surgery techniques, in combination with radiotherapy, have yielded significantly superior functional outcomes and prolonged survival in symptomatic metastatic epidural compression when compared to radiotherapy alone. Management of spinal metastases is evolving, and a multitude of factors determine the indication for and the technique and goals of surgical intervention. Between 1993 and 2005, 21.1% of patients with metastatic spinal tumors evaluated at The University of Texas M.D. Anderson Cancer Center were treated surgically by the Department of Neurosurgery. The most common spinal metastasis operated upon was metastatic kidney cancer (31.5%), even though kidney cancer was only the third most common primary tumor (after lung and breast cancers) giving rise to vertebral metastases observed during the same time period at this institution. This highlights the importance of the histology of the primary cancer (among other factors) in determining the indication for surgical intervention.
    Seminars in Oncology 05/2008; 35(2):108-17. DOI:10.1053/j.seminoncol.2007.12.005 · 3.94 Impact Factor
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    ABSTRACT: Hypothalamic hamartomas (HHs), rare developmental abnormalities of the inferior hypothalamus, often cause refractory, symptomatic, mixed epilepsy, including gelastic seizures. We present 37 patients with HH who underwent transcortical transventricular endoscopic resection. Between October 2003 and April 2005, 42 consecutive patients with refractory epilepsy who underwent endoscopic resection of HH were studied prospectively. The endoscope was held by an articulated pneumatic arm and tracked with a frameless stereotactic neuronavigation system. Data collection and follow-up were performed by personal interview. Five patients were excluded. The remaining 37 patients (22 males, 15 females; median age 11.8 years; range 8 months to 55 years) had frequent and usually multiple types of seizures. Postoperative MRI confirmed 100% resection of the HH from the hypothalamus in 12 patients. At last follow-up (median 21 months; range 13-28 months), 18 (48.6%) patients were seizure free. Seizures were reduced more than 90% in 26 patients (70.3%) and by 50% to 90% in 8 patients (21.6%). Overall, the mean postoperative stay was shorter in the endoscopic patients compared with our previously reported patients who underwent transcallosal resection (mean 4.1 days vs 7.7 days, respectively; p = 0.0006). The main complications were permanent short-term memory loss in 3 patients and small thalamic infarcts in 11 patients (asymptomatic in 9). Endoscopic resection of hypothalamic hamartoma (HH) is a safe and effective treatment for seizures. Its efficacy seems to be comparable to that of transcallosal resection of HH, but postoperative recovery time is significantly shorter.
    Neurology 05/2008; 70(17):1543-8. DOI:10.1212/01.wnl.0000310644.40767.aa · 8.30 Impact Factor

Publication Stats

1k Citations
192.58 Total Impact Points


  • 2013
    • The University of Arizona
      Tucson, Arizona, United States
  • 2011–2012
    • St. Luke's Medical Center (Phoenix)
      Phoenix, Arizona, United States
    • Barrow Neurological Institute
      • Department of Neurosurgery
      Phoenix, AZ, United States
  • 2006–2012
    • University of Texas MD Anderson Cancer Center
      • Department of NeuroSurgery
      Houston, TX, United States
  • 2002–2009
    • St. Joseph's Hospital and Medical Center (AZ, USA)
      • Department of Neurosurgery
      Phoenix, Arizona, United States
  • 2008
    • Phoenix Center
      Washington, Washington, D.C., United States
  • 2007
    • St. Joseph Medical Center
      Houston, Texas, United States