Hemorrhage risk of cerebral dural arteriovenous fistulas following Gamma Knife radiosurgery in a multicenter international consortium.

OBJECTIVE: The authors performed a study to evaluate the hemorrhagic rates of cerebral dural arteriovenous fistulas (dAVFs) and the risk factors of hemorrhage following Gamma Knife radiosurgery (GKRS). METHODS: Data from a cohort of patients undergoing GKRS for cerebral dAVFs were compiled from the International Radiosurgery Research Foundation. The annual posttreatment hemorrhage rate was calculated as the number of hemorrhages divided by the patient-years at risk. Risk factors for dAVF hemorrhage prior to GKRS and during the latency period after radiosurgery were evaluated in a multivariate analysis. RESULTS: A total of 147 patients with dAVFs were treated with GKRS. Thirty-six patients (24.5%) presented with hemorrhage. dAVFs that had any cortical venous drainage (CVD) (OR = 3.8, p = 0.003) or convexity or torcula location (OR = 3.3, p = 0.017) were more likely to present with hemorrhage in multivariate analysis. Half of the patients had prior treatment (49.7%). Post-GRKS hemorrhage occurred in 4 patients, with an overall annual risk of 0.84% during the latency period. The annual risks of post-GKRS hemorrhage for Borden type 2-3 dAVFs and Borden type 2-3 hemorrhagic dAVFs were 1.45% and 0.93%, respectively. No hemorrhage occurred after radiological confirmation of obliteration. Independent predictors of hemorrhage following GKRS included nonhemorrhagic neural deficit presentation (HR = 21.6, p = 0.027) and increasing number of past endovascular treatments (HR = 1.81, p = 0.036). CONCLUSIONS: Patients have similar rates of hemorrhage before and after radiosurgery until obliteration is achieved. dAVFs that have any CVD or are located in the convexity or torcula were more likely to present with hemorrhage. Patients presenting with nonhemorrhagic neural deficits and a history of endovascular treatments had higher risks of post-GKRS hemorrhage.

Evaluation of stereotactic radiosurgery for cerebral dural arteriovenous fistulas in a multicenter international consortium.

OBJECTIVE: In this multicenter study, the authors reviewed the results obtained in patients who underwent Gamma Knife radiosurgery (GKRS) for dural arteriovenous fistulas (dAVFs) and determined predictors of outcome. METHODS: Data from a cohort of 114 patients who underwent GKRS for cerebral dAVFs were compiled from the International Gamma Knife Research Foundation. Favorable outcome was defined as dAVF obliteration and no posttreatment hemorrhage or permanent symptomatic radiation-induced complications. Patient and dAVF characteristics were assessed to determine predictors of outcome in a multivariate logistic regression analysis; dAVF-free obliteration was calculated in a competing-risk survival analysis; and Youden indices were used to determine optimal radiosurgical dose. RESULTS: A mean margin dose of 21.8 Gy was delivered. The mean follow-up duration was 4 years (range 0.5-18 years). The overall obliteration rate was 68.4%. The postradiosurgery actuarial rates of obliteration at 3, 5, 7, and 10 years were 41.3%, 61.1%, 70.1%, and 82.0%, respectively. Post-GRKS hemorrhage occurred in 4 patients (annual risk of 0.9%). Radiation-induced imaging changes occurred in 10.4% of patients; 5.2% were symptomatic, and 3.5% had permanent deficits. Favorable outcome was achieved in 63.2% of patients. Patients with middle fossa and tentorial dAVFs (OR 2.4, p = 0.048) and those receiving a margin dose greater than 23 Gy (OR 2.6, p = 0.030) were less likely to achieve a favorable outcome. Commonly used grading scales (e.g., Borden and Cognard) were not predictive of outcome. Female sex (OR 1.7, p = 0.03), absent venous ectasia (OR 3.4, p < 0.001), and cavernous carotid location (OR 2.1, p = 0.019) were predictors of GKRS-induced dAVF obliteration. CONCLUSIONS: GKRS for cerebral dAVFs achieved obliteration and avoided permanent complications in the majority of patients. Those with cavernous carotid location and no venous ectasia were more likely to have fistula obliteration following radiosurgery. Commonly used grading scales were not reliable predictors of outcome following radiosurgery.

Stereotactic Radiosurgery for Acromegaly: An International Multicenter Retrospective Cohort Study.

BACKGROUND: Stereotactic radiosurgery (SRS) is a treatment option for persistent or recurrent acromegaly secondary to a growth hormone secreting pituitary adenoma, but its efficacy is inadequately defined. OBJECTIVE: To assess, in a multicenter, retrospective cohort study, the outcomes of SRS for acromegaly and determine predictors. METHODS: We pooled and analyzed data from 10 participating institutions of the International Gamma Knife Research Foundation for patients with acromegaly who underwent SRS with endocrine follow-up of ≥6 mo. RESULTS: The study cohort comprised 371 patients with a mean endocrine follow-up of 79 mo. IGF-1 lowering medications were held in 56% of patients who were on pre-SRS medical therapy. The mean SRS treatment volume and margin dose were 3.0 cm3 and 24.2 Gy, respectively. The actuarial rates of initial and durable endocrine remission at 10 yr were 69% and 59%, respectively. The mean time to durable remission after SRS was 38 mo. Biochemical relapse after initial remission occurred in 9%, with a mean time to recurrence of 17 mo. Cessation of IGF-1 lowering medication prior to SRS was the only independent predictor of durable remission (P = .01). Adverse radiation effects included the development of ≥1 new endocrinopathy in 26% and ≥1 cranial neuropathy in 4%. CONCLUSION: SRS is a definitive treatment option for patients with persistent or recurrent acromegaly after surgical resection. There appears to be a statistical association between the cessation of IGF-1 lowering medications prior to SRS and durable remission.

Effect of treatment period on outcomes after stereotactic radiosurgery for brain arteriovenous malformations: an international multicenter study.

OBJECTIVEThe role of and technique for stereotactic radiosurgery (SRS) in the management of arteriovenous malformations (AVMs) have evolved over the past four decades. The aim of this multicenter, retrospective cohort study was to compare the SRS outcomes of AVMs treated during different time periods.METHODSThe authors selected patients with AVMs who underwent single-session SRS at 8 different centers from 1988 to 2014 with follow-up ≥ 6 months. The SRS eras were categorized as early (1988-2000) or modern (2001-2014). Statistical analyses were performed to compare the baseline characteristics and outcomes of the early versus modern SRS eras. Favorable outcome was defined as AVM obliteration, no post-SRS hemorrhage, and no permanently symptomatic radiation-induced changes (RICs).RESULTSThe study cohort comprised 2248 patients with AVMs, including 1584 in the early and 664 in the modern SRS eras. AVMs in the early SRS era were significantly smaller (p < 0.001 for maximum diameter and volume), and they were treated with a significantly higher radiosurgical margin dose (p < 0.001). The obliteration rate was significantly higher in the early SRS era (65% vs 51%, p < 0.001), and earlier SRS treatment period was an independent predictor of obliteration in the multivariate analysis (p < 0.001). The rates of post-SRS hemorrhage and radiological, symptomatic, and permanent RICs were not significantly different between the two groups. Favorable outcome was achieved in a significantly higher proportion of patients in the early SRS era (61% vs 45%, p < 0.001), but the earlier SRS era was not statistically significant in the multivariate analysis (p = 0.470) with favorable outcome.CONCLUSIONSDespite considerable advances in SRS technology, refinement of AVM selection, and contemporary multimodality AVM treatment, the study failed to observe substantial improvements in SRS favorable outcomes or obliteration for patients with AVMs over time. Differences in baseline AVM characteristics and SRS treatment parameters may partially account for the significantly lower obliteration rates in the modern SRS era. However, improvements in patient selection and dose planning are necessary to optimize the utility of SRS in the contemporary management of AVMs.

Factors affecting early versus late remission in acromegaly following stereotactic radiosurgery.

Stereotactic radiosurgery (SRS) is a well-established treatment modality for patients with acromegaly. Our previously published study demonstrated a median time to remission of 29 months. This study aims to identify factors affecting the timing of remission and also to quantify the rate of late remission. This is a retrospective analysis of acromegaly patients who underwent SRS between 1988 and 2016. Early and late remissions were defined based on our prior median remission time of 29 months. The median imaging and endocrine follow-ups are 66 and 104.8 months, respectively. Multivariate analysis was conducted to analyze factors leading to late remission. A total number of 157 patients, of those 102 (64.9%) patients achieved remission. of those 102 patients, 62 patients (60.7%) had remission in less than 29 months (early remission) whereas 40 patients (39.3%) achieved remission later than (late remission) 29 months. The two groups differed significantly in the time interval between the last resection and the first SRS (p = 0.040) whole sella radiosurgery (p = 0.025) or radiosurgery to the cavernous sinus (p = 0.041). Competing risk analysis showed the interval between resection and SRS was significantly longer in the late remission group (HR 1.013, 95% CI 1.004-1.02; p = 0.007). Fifty-one of 157 patients (32.5%) developed a new endocrine deficiency following SRS. Those with shorter time between resection and SRS were more likely to achieve early remission. While most patients achieve remission in less than 4 years, the latency of effect with SRS yields a small percentage of patients achieving remission beyond that time point.

Stereotactic radiosurgery for WHO grade I posterior fossa meningiomas: long-term outcomes with volumetric evaluation.

OBJECTIVEResearch over the past 2 decades has been characterizing the role of stereotactic radiosurgery (SRS) in the treatment of benign intracranial tumors, including meningiomas. However, few studies have examined the long-term outcomes of SRS treatment for posterior fossa meningiomas (PFMs). Furthermore, previous studies have typically used single diameter measurements when reporting outcomes, which can yield misleading results. The authors describe the use of SRS in the treatment of benign WHO grade I PFMs and correlate volumetric analysis with long-term outcomes.METHODSThis study is a retrospective analysis of a prospectively maintained IRB-approved database. Inclusion criteria were a diagnosis of WHO grade I PFM with subsequent treatment via single-session SRS and a minimum of 3 follow-up MRI studies available. Volumetric analysis was performed on the radiosurgical scan and each subsequently available follow-up scan by using slice-by-slice area calculations of the meningioma and numerical integration with the trapezoid rule.RESULTSThe final cohort consisted of 120 patients, 76.6% (92) of whom were female, with a median age of 61 years (12-88 years). Stereotactic radiosurgery was the primary treatment for 65% (78) of the patients, whereas 28.3% (34) had 1 resection before SRS treatment and 6.7% (8) had 2 or more resections before SRS. One patient had prior radiotherapy. Tumor characteristics included a median volume of 4.0 cm3 (0.4-40.9 cm3) at treatment with a median margin dose of 15 Gy (8-20 Gy). The median clinical and imaging follow-ups were 79.5 (15-224) and 72 (6-213) months, respectively. For patients treated with a margin dose ≥ 16 Gy, actuarial progression-free survival rates during the period 2-10 years post-SRS were 100%. In patients treated with a margin dose of 13-15 Gy, the actuarial progression-free survival rates at 2, 4, 6, 8, and 10 years were 97.5%, 97.5%, 93.4%, 93.4%, and 93.4%, respectively. Those who were treated with ≤ 12 Gy had actuarial progression-free survival rates of 95.8%, 82.9%, 73.2%, 56.9%, and 56.9% at 2, 4, 6, 8, and 10 years, respectively. The overall tumor control rate was 89.2% (107 patients). Post-SRS improvement in neurological symptoms occurred in 23.3% (28 patients), whereas symptoms were stable in 70.8% (85 patients) and worsened in 5.8% (7 patients). Volumetric analysis demonstrated that a change in tumor volume at 3 years after SRS reliably predicted a volumetric change and tumor control at 5 years (R2 = 0.756) with a p < 0.001 and at 10 years (R2 = 0.421) with a p = 0.001. The authors also noted that the 1- to 5-year tumor response is predictive of the 5- to 10-year tumor response (R2 = 0.636, p < 0.001).CONCLUSIONSStereotactic radiosurgery, as an either upfront or adjuvant treatment, is a durable therapeutic option for WHO grade I PFMs, with high tumor control and a low incidence of post-SRS neurological deficits compared with those obtained using alternate treatment modalities. Lesion volumetric response at the short-term follow-up of 3 years is predictive of the long-term response at 5 and 10 years.

A Long-Term Study of the Treatment of Nelson's Syndrome With Gamma Knife Radiosurgery.

BACKGROUND: Nelson's syndrome may be a devastating complication for patients with Cushing's disease who underwent a bilateral adrenalectomy. Previous studies have demonstrated that stereotactic radiosurgery (SRS) can be used to treat patients with Nelson's syndrome. OBJECTIVE: To report a retrospective study of patients with Nelson's syndrome treated with Gamma Knife radiosurgery to evaluate the effect of SRS on endocrine remission and tumor control. METHODS: Twenty-seven patients with Nelson's syndrome treated with Gamma Knife radiosurgery after bilateral adrenalectomy were included in this study. After radiosurgery, patients were followed with serial adrenocorticotropic hormone (ACTH) levels and MRI sequences to assess for endocrine remission and tumor control. Cox proportional hazards regression analysis was used to evaluate the relationship between the time to remission and potential prognostic factors. RESULTS: In 21 patients with elevated ACTH prior to SRS and endocrine follow-up data, 14 (67%) had decreased or stable ACTH levels, and 7 achieved a normal ACTH level at a median of 115 mo (range 7-272) post-SRS. Tumor volume was stable or reduced after SRS in 92.5% of patients (25/27) with radiological follow-up. Time to remission was not significantly associated with the ACTH prior to SRS (P = .252) or with the margin dose (P = .3). However, a shorter duration between the patient's immediate prior transsphenoidal resection and SRS was significantly associated with a shorter time to remission (P = .045). CONCLUSION: This retrospective analysis suggests that SRS is an effective means of achieving endocrine remission and tumor control in patients with Nelson's syndrome.

Outcomes of stereotactic radiosurgery for foramen magnum meningiomas: an international multicenter study.

OBJECTIVE Meningiomas are the most common benign extramedullary lesions of the foramen magnum; however, their optimal management remains undefined. Given their location, foramen magnum meningiomas (FMMs) can cause significant morbidity, and complete microsurgical removal can be challenging. Anterior and anterolateral FMMs carry greater risks with surgery, but they comprise the majority of these lesions. As an alternative to resection, stereotactic radiosurgery (SRS) has been used to treat FMMs in small case series. To more clearly define the outcomes of SRS and to delineate a rational management paradigm for these lesions, the authors analyzed the safety and efficacy of SRS for FMM in an international multicenter trial. METHODS Seven medical centers participating in the International Gamma Knife Research Foundation (IGKRF) provided data for this retrospective cohort study. Patients who were treated with Gamma Knife radiosurgery and whose clinical and radiological follow-up was longer than 6 months were eligible for study inclusion. Data from pre- and post-SRS radiological and clinical evaluations were analyzed. Stereotactic radiosurgery treatment variables were recorded. RESULTS Fifty-seven patients (39 females and 18 males, with a median age of 64 years) met the study inclusion criteria. Thirty-two percent had undergone prior microsurgical resection. Patients most frequently presented with cranial neuropathy (39%), headache (35%), numbness (32%), and ataxia (30%). Median pre-SRS tumor volume was 2.9 cm3. Median SRS margin dose was 12.5 Gy (range 10-16 Gy). At the last follow-up after SRS, 49% of tumors were stable, 44% had regressed, and 7% had progressed. Progression-free survival rates at 5 and 10 years were each 92%. A greater margin dose was associated with a significantly increased likelihood of tumor regression, with 53% of tumors treated with > 12 Gy regressing. Fifty-two percent of symptomatic patients noted some clinical improvement. Adverse radiation effects were limited to hearing loss and numbness in 1 patient (2%). CONCLUSIONS Stereotactic radiosurgery for FMM frequently results in tumor control or tumor regression, as well as symptom improvement. Margin doses > 12 Gy were associated with increased rates of tumor regression. Stereotactic radiosurgery was generally safe and well tolerated. Given its risk-benefit profile, SRS may be particularly useful in the management of small- to moderate-volume anterior and anterolateral FMMs.

Stereotactic radiosurgery for Spetzler-Martin Grade IV and V arteriovenous malformations: an international multicenter study.

OBJECTIVE Due to the complexity of Spetzler-Martin (SM) Grade IV-V arteriovenous malformations (AVMs), the management of these lesions remains controversial. The aims of this multicenter, retrospective cohort study were to evaluate the outcomes after single-session stereotactic radiosurgery (SRS) for SM Grade IV-V AVMs and determine predictive factors. METHODS The authors retrospectively pooled data from 233 patients (mean age 33 years) with SM Grade IV (94.4%) or V AVMs (5.6%) treated with single-session SRS at 8 participating centers in the International Gamma Knife Research Foundation. Pre-SRS embolization was performed in 71 AVMs (30.5%). The mean nidus volume, SRS margin dose, and follow-up duration were 9.7 cm3, 17.3 Gy, and 84.5 months, respectively. Statistical analyses were performed to identify factors associated with post-SRS outcomes. RESULTS At a mean follow-up interval of 84.5 months, favorable outcome was defined as AVM obliteration, no post-SRS hemorrhage, and no permanently symptomatic radiation-induced changes (RIC) and was achieved in 26.2% of patients. The actuarial obliteration rates at 3, 7, 10, and 12 years were 15%, 34%, 37%, and 42%, respectively. The annual post-SRS hemorrhage rate was 3.0%. Symptomatic and permanent RIC occurred in 10.7% and 4% of the patients, respectively. Only larger AVM diameter (p = 0.04) was found to be an independent predictor of unfavorable outcome in the multivariate logistic regression analysis. The rate of favorable outcome was significantly lower for unruptured SM Grade IV-V AVMs compared with ruptured ones (p = 0.042). Prior embolization was a negative independent predictor of AVM obliteration (p = 0.024) and radiologically evident RIC (p = 0.05) in the respective multivariate analyses. CONCLUSIONS In this multi-institutional study, single-session SRS had limited efficacy in the management of SM Grade IV-V AVMs. Favorable outcome was only achieved in a minority of unruptured SM Grade IV-V AVMs, which supports less frequent utilization of SRS for the management of these lesions. A volume-staged SRS approach for large AVMs represents an alternative approach for high-grade AVMs, but it requires further investigation.

Cavernous carotid stenosis following stereotactic radiosurgery for Cushing's disease: A rare complication and review of the literature.

Intracranial carotid stenosis or occlusion after SRS is an extraordinarily rare event. Because of the rarity of this event, increased awareness within the neurosurgical community is required. For those with post-radiosurgical carotid stenosis who are asymptomatic, longitudinal follow up is recommended. Management depends on whether the patient is symptomatic or asymptomatic. Those who are symptomatic may require balloon angioplasty, stenting, or bypass surgery.

Stereotactic Radiosurgery of Central Skull Base Meningiomas-Volumetric Evaluation and Long-Term Outcomes.

BACKGROUND AND OBJECTIVE: Complete resection of a central skull base meningioma (CSM) is possible, but it is often associated with high morbidity. Stereotactic radiosurgery (SRS) plays an appreciable role in the management of skull base meningiomas. This study aims to apply volumetric methods to assess the CSM response after SRS and correlate it with clinical outcomes. MATERIALS AND METHODS: The cohort consisted of 219 patients, of whom 73.9% were female (n = 162), with a median age of 55 years (19-88). SRS was the primary treatment for 45.7% (n = 100), while 37.9% (n = 83) underwent treatment for residual tumors, 14.2% (n = 31) for recurrence, and in 5 with others reasons. The median tumor volume was 4.9 cm3 (0.3-105 cm3) to a median margin dose of 14 Gy (5-35 Gy). Volumetric analysis of CSM was performed on the SRS scan and each available magnetic resonance image thereafter. RESULTS: The median clinical and imaging follow-ups of the cohort were 72 (24-298) and 66 (18-298) months, respectively. The overall tumor control rate was 83.4% (n = 183) at last follow-up with tumor regression 72.1% (n = 158). Neurologic symptoms were improved after SRS in 6.8% (n = 15), stable in 72.6% (n = 159), and worsened in 20.5% (n = 45). The clinical deterioration usually occurred in the patients with tumor progression (P < 0.001). Following SRS, the volumetric analysis confirmed that tumor response at 3 years reliably projected volumetric change and tumor control at 5 years (R2 = 0.694) with P < 0.001 and 10 years (R2 = 0.571) with P = 0.001. CONCLUSION: SRS affords effective tumor volumetric control and neurologic stability or improvement in the majority of patients with CSMs. The radiologic response of CSM as determined by volumetry at 3 years post-SRS is predictive of long-term tumor response at 5 and 10 years following SRS.

Stereotactic Radiosurgery for Cushing Disease: Results of an International, Multicenter Study.

Context: Cushing disease (CD) due to adrenocorticotropic hormone-secreting pituitary tumors can be a management challenge. Objective: To better understand the outcomes of stereotactic radiosurgery (SRS) for CD and define its role in management. Design: International, multicenter, retrospective cohort analysis. Setting: Ten medical centers participating in the International Gamma Knife Research Foundation. Patients: Patients with CD with >6 months endocrine follow-up. Intervention: SRS using Gamma Knife radiosurgery. Main Outcome Measures: The primary outcome was control of hypercortisolism (defined as normalization of free urinary cortisol). Radiologic response and adverse radiation effects (AREs) were recorded. Results: In total, 278 patients met inclusion criteria, with a mean follow-up of 5.6 years (0.5 to 20.5 years). Twenty-two patients received SRS as a primary treatment of CD. Mean margin dose was 23.7 Gy. Cumulative initial control of hypercortisolism was 80% at 10 years. Mean time to cortisol normalization was 14.5 months. Recurrences occurred in 18% with initial cortisol normalization. Overall, the rate of durable control of hypercortisolism was 64% at 10 years and 68% among patients who received SRS as a primary treatment. AREs included hypopituitarism (25%) and cranial neuropathy (3%). Visual deficits were related to treatment of tumor within the suprasellar cistern (P = 0.01), whereas both visual (P < 0.0001) and nonvisual cranial neuropathy (P = 0.02) were related to prior pituitary irradiation. Conclusions: SRS for CD is well tolerated and frequently results in control of hypercortisolism. However, recurrences can occur. SRS should be considered for patients with persistent hypercortisolism after pituitary surgery and as a primary treatment in those unfit for surgery. Long-term endocrine follow-up is essential after SRS.

Postoperative hematoma involving brainstem, peduncles, cerebellum, deep subcortical white matter, cerebral hemispheres following chronic subdural hematoma evacuation.

Among the intracranial hematomas, chronic subdural hematomas (CSDH) are the most benign with a mortality rate of 0.5-4.0%. The elderly and alcoholics are commonly affected by CSDH. Even though high percentage of CSDH patients improves after the evacuation, there are some unexpected potential complications altering the postoperative course with neurological deterioration. Poor outcome in postoperative period is due to complications like failure of brain to re-expand, recurrence of hematoma and tension pneumocephalus. We present a case report with multiple intraparenchymal hemorrhages in various locations like brainstem, cerebral and cerebellar peduncles, right cerebellar hemisphere, right thalamus, right capsulo-ganglionic region, right corona radiata and cerebral hemispheres after CSDH evacuation. Awareness of this potential problem and the immediate use of imaging if the patient does not awake from anesthesia or if he develops new onset focal neurological deficits, are the most important concerns to the early diagnosis of this rare complication.

Predictors of visual outcome with transsphenoidal excision of pituitary adenomas having suprasellar extension: A prospective series of 100 cases and brief review of the literature.

OBJECTIVE: The aim was to assess the factors influencing the visual outcome following trans-sphenoidal excision of pituitary adenomas. MATERIALS AND METHODS: One hundred consecutive patients of pituitary adenomas with suprasellar extension (SSE) were operated by trans-sphenoidal approach from July 2003 to December 2006. There were 52 male and 48 female patients with a mean age of 42.47 years. The visual impairment score, which was used to evaluate the visual outcome was produced by adding the scores for visual acuity and visual field defects of each patient (from the tables of the German Ophthalmological Society). The mean diameter, the SSE and the parasellar extension of the lesion were noted in the magnetic resonance imaging study. The average follow-up was 43.5 months. RESULTS: The mean diameter of the tumor was 32.97 mm, and the mean SSE was 14.95 mm. The parasellar extension was present in 27 patients. The vision improved in 61 of the 71 patients (85.91%). The shorter the duration of visual symptoms and smaller the size of the lesion resulted in better visual outcome. The age and the preoperative visual impairment did not show any correlation with the visual outcome. CONCLUSIONS: Patients with visual symptoms of <1-year duration (P < 0.01) and adenomas of <36.5 mm diameter (P < 0.009) have better visual outcome.

Clival giant cell tumor - A rare case report and review of literature with respect to current line of management.

Giant-cell tumor (GCT) involving the skull base is rare. Sphenoid bone is the most commonly involved bone followed by petrous temporal bone. Histopathology and radiological features of these lesions are similar to GCT involving bone elsewhere. Unlike other sites, skull base is not an ideal site for the radical surgery. Hence adjuvant treatment has pivotal role. Radiation therapy with intensity-modulated radiation therapy, stereotactic radiosurgery or chemotherapy with adriamycin are promising as described in some case reports. Bisphosphonates showed good control in local recurrence. In vitro studies with Zolendronate loaded bone cement and phase 2 trials of Denosumab showed hopeful results, may be useful in future.

C2 Primary leiomyoma in an immunocompetent woman: A case report and review of literature.

Clinical case report and review of the literature. This is the first case of primary leiomyoma in an immunocompetent woman without previous history of uterine leiomyoma being reported in the literature to the best of our knowledge. Leiomyoma, a type of smooth muscle cell tumor, involving the vertebra is extremely rare. There were very few primary leiomyoma in patients with AIDS or in the immune-suppressed patients. This 48-year-old female came with H/o neck pain, weakness and bladder retention. On examination, tone increased in all four limbs, power on the right side of the limbs 4/5, power on the left upper limb 0/5, lower limb 3/5, left plantar was up going, decreased sensation over the left second cervical vertebra (C2) dermatome and all modalities decreased below C2. X-ray and magnetic resonance imaging (MRI) of the cervical spine showed kyphosis of the cervical spine with destruction of the C2 vertebral body along with pathological fracture. The patient underwent decompression of the C2 lesion through the C2 right pedicle with occipito-C1-C3 lateral mass screws fixation. Lesion anterior to the cord was reached by a transpedicular approach and decompression was performed. The lesion was pinkish grey, firm and moderately vascular and was destroying the C2 vertebral body. The patient improved symptomatically in power in the left upper limb and lower limb over the next 1 week duration from 0/5 to 4+/5. Histopathology revealed primary leiomyoma. The patient was evaluated with ultrasound abdomen and contrast tomogram of the chest, abdomen and pelvis to rule out other possible lesions in the lung, intestines and uterus. We suggest that leiomyoma should be included in the differential diagnosis of destructive lytic lesions involving the C2 vertebra. Histopathological examination with immunohistochemistry is necessary for the definitive diagnosis. Treatment of choice is surgery with complete removal.

Stereotactic Radiosurgery for Pediatric High-Grade Brain Arteriovenous Malformations: Our Experience and Review of Literature.

INTRODUCTION: Although high-grade AVMs pose a particularly high lifetime hemorrhage risk to pediatric patients (age <18 years), little is known about the treatment outcomes. Therefore, the aim of this retrospective cohort study was to evaluate the outcomes after single-session stereotactic radiosurgery (SRS) for pediatric high-grade AVMs. METHODS: We reviewed baseline and treatment outcomes data from pediatric patients aged less than 18 years with Spetzler-Martin grade IV AVMs treated with SRS in a single session at our institution. The study cohort comprised 28 pediatric patients with Spetzler-Martin grade IV AVMs, with a mean age of 12.1 years. Statistical analyses were performed to determine predictors of obliteration and compare the outcomes of patients with versus without previous AVM hemorrhage. RESULTS: The mean nidus volume, radiosurgical margin dose, and follow-up duration were 5.9 cm3, 19.4 Gy, and 116 months, respectively. The actuarial obliteration rates at 3, 5, 7, and 10 years were 11%, 19%, 29%, and 35%, respectively. Older age was significantly associated with obliteration in the univariate Cox proportional regression analysis (P = 0.01). During the latency period before obliteration, the annual post-SRS hemorrhage rate was 3.2%. Symptomatic and permanent radiation-induced changes were detected in 7.1% and 3.5%, respectively. A favorable outcome was achieved in 35.7%, and it was more frequently achieved for those with ruptured AVMs (P = 0.0484). CONCLUSIONS: The efficacy of single-session SRS for the treatment of high-grade AVMs in the pediatric population is limited, particularly for those with unruptured nidi. Multimodal therapies should be considered in the management of selected pediatric high-grade AVMs. However, further prospective analyses are warranted to define the optimal management strategy for these challenging vascular malformations.

Morphometric analysis of posterior fossa in Indian CP angle acoustic schwannoma patients.

AIM: To study the morphometry of posterior fossa in Indian CP angle schwannoma patients in order to know its influence on the extent of excision of the CP angle acoustic schwannomas. MATERIALS AND METHODS: One hundred cases of cerebellopontine angle schwannomas treated surgically by the senior author and 20 controls between January 2006 and June 2011 were consecutively investigated with computed tomography (CT) using the high-resolution CT bone windows before surgery. Evaluation of anatomic parameters of the petrous bone and posterior fossa cavity were done in all patients and controls. Data were entered in Excel software and were analyzed using NCSS software. All possible regression analysis was done to select the important variables to be included in the model to predict the excision of tumor with these variables. A prediction model was developed defining the binary outcome as total excision or subtotal excision as dependent variable and the morphometric data and grading of tumor as independent variables. RESULTS: Interpetrous distance (IP) is the distance between the two petrous apices. Sigmoid distance (IS) distance is the distance between the two sigmoid points. Sigmoid point is the point at which the scalloped impression of the sigmoid sinus straightens to join the occipital bone posteriorly. SAG is the distance between the mid IP point and the mid-point on the inner wall of the occipital bone. The PM angle was 47.8±4.14 degrees (38-58), the PA angle was 42.68±4.47 degrees (34-53), the IP distance was 2.07±0.13 cm (1.5-2.8), the sagittal diameter of posterior fossa was 6.22±0.73 cm (5.1-9.8) and the intersigmoid distance was 9.45±0.73 cm (7.4-11). There was no significant gender difference in the posterior fossa morphometry between patients and controls. Inter-sigmoid distance and the petrous-apex angle were more in the Indians when compared to the European population mentioned in the Mathies and Samii study. CONCLUSIONS: The posterior fossa morphological parameters of the Indian and European population differ significantly. Inter-sigmoid distance and the petrous-apex angle were more in the Indians when compared to the Europeans. There is no significant gender difference in the morphometry of the Indians. There is no significant difference between the patients and the control groups. In our study the adhesions with surrounding structures along with the posterior fossa morphometry significantly affect the extent of excision.

Parietal pilomyxoid astrocytoma with recurrence in 10 months: A case report and review of literature.

Pilomyxoid astrocytoma (PMA) is a new entity described in WHO 2007 classification of brain tumors. Pilocytic astrocytoma (PA) and PMA share many histopathological features with a few differences in histopathology and behavior of the tumor. This tumor is commonly located in the hypothalamic chiasmatic region. PMA behaves more aggressively than PA, with shorter progression-free survival as well as a higher rate of recurrence and CNS dissemination. We describe a case of PMA in a 10-year-old male involving left parietal lobe presenting with raised ICP features along with the follow-up. Patient was symptom free after 7 months of postoperative and 5½ months of post-radiation. The unusual site and atypical Magnetic resonance imaging features are distinctive in this case report.

Atypical pediatric ganglioglioma is common and associated with a less favorable clinical course.

OBJECT Ganglioglioma (GG) is commonly recognized as a low-grade tumor located in the temporal lobe, often presenting with seizures. Most are amenable to complete resection and are associated with excellent oncological outcome. The authors encountered several GGs in various locations, which seem to have a less favorable clinical course than GGs in the temporal lobe. METHODS The authors performed a single-center retrospective review of all children with a histological diagnosis of GG who were treated at Children's Hospital Colorado between 1997 and 2013. Each tumor was categorized by 2 pediatric neuroradiologists as typical or atypical based on preoperative MRI appearance. Typical lesions were cortically based, within a single cerebral lobe, well-circumscribed, and solid or mixed solid/cystic. The treatment and clinical course of each patient was analyzed. RESULTS Thirty-seven children were identified, with a median age at presentation of 8.2 years and median follow-up of 38.0 months. Eighteen tumors (48.6%) were typical and 19 (51.4%) were atypical. All typical lesions presented with seizures, whereas no atypical lesions did so. Sixteen (88.9%) typical lesions were located in the temporal lobe. In the atypical group, tumor location was variable, including 11 (57.9%) in the brainstem. Death during follow-up was statistically more common in the atypical group (31.6% vs 0%, p = 0.02). Gross-total resection (GTR) was achieved for 15 of 16 typical tumors (93.8%), compared with 3 atypical tumors (15.8%, p < 0.0001). Presentation with seizure or non-brainstem location were each associated with survival (p = 0.02 and 0.004, respectively). The presence of mutation in BRAF exon 15 did not differ between the 2 groups. CONCLUSIONS Pediatric GG with typical imaging features is associated with excellent rates of GTR and overall survival. Atypical GG is commonly encountered, less amenable to GTR, and associated with a worse outcome. This may relate to anatomical or biological characteristics and merits further investigation.