Faculty Bibliography

OBJECTIVE: Incisional cerebrospinal fluid (CSF) leakage after cranial surgery is a significant cause of morbidity due to poor wound healing and infection, meningitis, and pseudomeningocele formation. Many common dural closure techniques, such as sutures, autologous grafts, gelatin or collagen sponges, and fibrin glues, are used to achieve watertight closure, although none are US Food and Drug Administration approved for this use. DuraSeal Dural Sealant System is a polyethylene glycol (PEG) hydrogel approved by the U.S. Food and Drug Administration for obtaining watertight dural closure when applied after standard dural suturing. This multicenter, prospective randomized study further evaluated the safety of a PEG hydrogel compared with common dural sealing techniques. METHODS: A total of 237 patients undergoing elective cranial surgery at 17 institutions were randomized to dural closure augmented with the PEG hydrogel or a control "standard of care" dural sealing technique after Valsalva maneuver demonstrated an intraoperative nonwatertight dural closure. Data were collected on complications resulting in unplanned postoperative interventions or reoperations, surgical site infections, CSF leaks, and other neurological complications within 30 days. Surgeons also provided data on the ease of use of the dural sealing techniques, as well as preparation and application times. RESULTS: The incidences of neurosurgical complications, surgical site infections, and CSF leaks were similar between treatment and control groups, with no statistically significant difference between the measures. In the PEG hydrogel group (n = 120), the incidence of neurosurgical complications was 5.8% (n = 7), the incidence of surgical site infections was 1.7% (n = 2), and the incidence of CSF leak was 0.8% (n = 1). In the control group (n = 117), the incidence of neurosurgical complications was 7.7% (n = 9), the incidence of surgical site infection was 2.6% (n = 3), and the incidence of CSF leak was 1.7% (n = 2). Sealant preparation time was less than 5 minutes in 96.6% of the PEG hydrogel group compared with 66.4% of controls (P < 0.001). The dural augmentation was applied in less than 1 minute in 85.7% of the PEG hydrogel group compared with 66.4% of the control group (P < 0.001). CONCLUSIONS: The PEG hydrogel dural sealant used in this study has a similar safety profile to commonly used dural sealing techniques when used as dural closure augmentation in cranial surgery. The PEG hydrogel dural sealant demonstrated faster preparation and application times than other commonly used dural sealing techniques.

INTRODUCTION: : Glutamic acid decarboxylase (GAD) is the rate-limiting enzyme converting glutamate into gamma-aminobutyric acid. Impaired GAD function can alter motor, cognitive, and behavioral function. Anti-GAD antibodies (GADAbs) can cause several neurological disorders. However, the association between anti-GADAbs and pure psychosis, without seizures or focal neurological deficits, is not well defined. CASE REPORT: : A 19-year-old woman with recent-onset psychotic disorder was diagnosed with schizophrenia. Brain magnetic resonance imaging and cerebrospinal fluid analysis were normal. Serum anti-GADAb titers were elevated. Brain biopsy showed subcortical gliosis and microglia-macrophage infiltration. The clinical syndrome improved with immune therapy. CONCLUSIONS: : Severe psychosis and mild cognitive decline without other neurological features, meeting the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revision diagnostic criteria for schizophrenia, can result from brain inflammation associated with elevated serum anti-GADAbs.

Object The presence of angiogenesis is a hallmark of glioblastoma (GBM). Vascular endothelial growth factor (VEGF), which drives angiogenesis, provides an additional target for conventional therapy. The authors conducted a prospective clinical trial to test the effectiveness of bevacizumab, an inhibitor of VEGF, in newly diagnosed GBM. Methods From 2006 through 2010, 51 eligible patients with newly diagnosed GBM were treated with involved-field radiation therapy and concomitant temozolomide (75 mg/m(2) daily for 42 days) along with bevacizumab (10 mg/kg every 2 weeks), starting 29 days after surgery. This was followed by 6 cycles of adjuvant temozolomide therapy (150 mg/m(2) on Days 1-7 of a 28-day cycle) with bevacizumab administered at 10 mg/kg on Days 8 and 22 of each 28-day cycle. Results The 6- and 12-month progression-free survival (PFS) rates were 85.1% and 51%, respectively. The 12- and 24-month overall survival (OS) rates were 85.1% and 42.5%, respectively. Grade III/IV toxicities were noted in 10 patients (19.6%). No treatment-related deaths were observed. Asymptomatic intracranial bleeding was noted in 5 patients. Conclusions The addition of bevacizumab to conventional therapy in newly diagnosed GBM appears to improve both PFS and OS in patients with newly diagnosed GBM, with acceptable morbidity. A shift toward diffuse relapse was noted in a significant number of patients. Ongoing Phase III clinical trials will show the true benefit of this antiangiogenic approach.

PURPOSE: Local recurrence is the dominant pattern of relapse in high-grade glioma (HGG) after conventional therapy. The recent use of antiangiogenic therapy has shown impressive radiologic and clinical responses in adult HGG. The preclinical data suggesting increased invasiveness after angiogenic blockade have necessitated a detailed analysis of the pattern of recurrence after therapy. METHODS AND MATERIALS: A total of 162 consecutive patients with HGG, either newly diagnosed (n = 58) or with recurrent disease (n = 104) underwent therapy with bevacizumab at 10 mg/kg every 2 weeks and conventional chemotherapy with or without involved field radiotherapy until disease progression. The pattern of recurrence and interval to progression were the primary aims of the present study. Diffuse invasive recurrence (DIR) was defined as the involvement of multiple lobes with or without crossing the midline. RESULTS: At a median follow-up of 7 months (range, 1-37), 105 patients had recurrence, and 79 patients ultimately developed DIR. The interval to progression was similar in the DIR and local recurrence groups (6.5 and 6.3 months, p = .296). The hazard risk of DIR increased exponentially with time and was similar in those with newly diagnosed and recurrent HGG (R(2) = 0.957). The duration of bevacizumab therapy increased the interval to recurrence (p < .0001) and improved overall survival (p < .0001). However, the pattern of relapse did not affect overall survival (p = .253). CONCLUSION: Along with an increase in median progression-free survival, bevacizumab therapy increased the risk of DIR in HGG patients. The risk of increased invasion with prolonged angiogenic blockade should be addressed in future clinical trials

OBJECT: In this paper, the authors' goal was to analyze the incidence, timing, and treatment of new metastases following initial treatment with 20-Gy Gamma Knife surgery (GKS) alone in patients with limited brain metastases without whole-brain radiation therapy (WBRT). METHODS: A retrospective analysis of 114 consecutive adults (75 women and 34 men; median age 61 years) with KPS scores of 60 or higher who received GKS for 1-3 brain metastases </= 2 cm was performed (median lesion volume 0.35 cm(3)). Five patients lacking follow-up data were excluded from analysis. After treatment, patients underwent MR imaging at 6 weeks and every 3 months thereafter. New metastases were preferentially treated with additional GKS. Indications for WBRT included development of numerous metastases, leptomeningeal disease, or diffuse surgical-site recurrence. RESULTS: The median overall survival from GKS was 13.8 months. Excluding the 3 patients who died before follow-up imaging, 12 patients (11.3%) experienced local failure at a median of 7.4 months. Fifty-three patients (50%) developed new metastases at a median of 5 months. Six (7%) of 86 instances of new lesions were symptomatic. Most patients (67%) with distant failures were successfully treated using salvage GKS alone. Whole-brain radiotherapy was indicated in 20 patients (18.3%). Thirteen patients (11.9%) died of neurological disease. CONCLUSIONS: For patients with limited brain metastases and functional independence, 20-Gy GKS provides excellent disease control and high-functioning survival with minimal morbidity. New metastases developed in almost 50% of patients, but additional GKS was extremely effective in controlling disease. Using our algorithm, fewer than 20% of patients required WBRT, and only 12% died of progressive intracranial disease

Purpose: The role of invasion as a prognostic factor in high-grade gliomas (HGG) remains controversial. An apparent increase in invasiveness following anti-angiogenic therapy makes this question clinically relevant. The goal of this study is to assess survival differences in patients with newly diagnosed HGG who present with diffuse invasive disease compared to those who did not, but went on to develop diffuse invasive disease following bevacizumab therapy. Materials and Methods: Twenty-three patients presented as newly diagnosed diffuse invasive HGG. All patients underwent surgical resection with radiation therapy and temozolomide for one year. Progression-free survival (PFS) and overall survival (OS) were compared to a control of 58 patients with focal high-grade glioma who received similar therapy, but that included bevacizumab at 10 mg/kg given every two weeks. Results: The patient characteristics were similar in each group. The median PFS and OS for invasive HGG patients were 6 and 13 months and for the focal HGG patients, 11 and 24 months, respectively (P=0.092 and P=0.071). In the subgroup of invasive HGG that showed significant angiogenesis, the median PFS and OS were 3 and 9 months, respectively. 56% of the focal HGG patients recurred as diffuse invasive relapse. For patients with focal HGG who recurred as invasive disease, the median PFS and OS were 9 and 21 months respectively. Conclusions: Presence of diffuse invasive disease not accompanied by angiogenesis either prior to therapy or subsequent to anti-angiogenic therapy does not seem to have prognostic significance. However, invasion accompanied by angiogenesis in newly diagnosed HGG may confer a poor prognosis