Neuropathological and Neuroradiological Spectrum of Pediatric Malignant Gliomas: Correlation With Outcome

Neurosurgery 69:215–224, 2011 DOI: 10.1227/NEU.0b013e3182134340

The diagnostic accuracy and reproducibility for glioma histological diagnosis are suboptimal.

OBJECTIVE: To characterize radiological and histological features in pediatric malignant gliomas and to determine whether they had an impact on survival.

METHODS: We retrospectively reviewed a series of 96 pediatric malignant gliomas. All histological samples were blindly and independently reviewed and classified according to World Health Organization 2007 and Sainte-Anne classifications. Radiological features were reviewed independently. Statistical analyses were performed to investigate the relationship between clinical, radiological, and histological features and survival.

RESULTS: Cohort median age was 7.8 years; median follow-up was 4.8 years. Tumors involved cerebral hemispheres or basal ganglia in 82% of cases and brainstem in the remaining 18%. After histopathological review, low-grade gliomas and nonglial tumors were excluded (n = 27). The World Health Organization classification was not able to demonstrate differences between groups and patients survival. The Sainte-Anne classification identified a 3-year survival rate difference between the histological subgroups (oligodendroglioma A, oligodendroglioma B, malignant glioneuronal tumors, and glioblastomas; P = .02). The malignant glioneuronal tumor was the only glioma subtype with specific radiological features. Tumor location was significantly associated with 3-year survival rate (P = .005). Meningeal attachment was the only radiological criteria associated with longer survival (P = .02).

CONCLUSION: The Sainte-Anne classification was better able to distinguish pediatric malignant gliomas in terms of survival compared with the World Health Organization classification. In this series, neither of these 2 histological classifications provided a prognostic stratification of the patients.

Endonasal endoscopic resection of esthesioneuroblastoma: the Johns Hopkins Hospital experience and review of the literature

Neurosurg Rev. DOI 10.1007/s10143-011-0329-2

Esthesioneuroblastoma is an uncommon malignant tumor originating in the upper nasal cavity. The surgical treatment for this tumor has traditionally been via an open craniofacial resection. Over the past decade, there has been tremendous development in endoscopic techniques.

In this report, we performed a retrospective analysis of patients with esthesioneuroblastomas treated with a purely endonasal endoscopic approach and resection at the Johns Hopkins Hospital between January 2005 and April 2010.

A total of eight patients with esthesioneuroblastoma, five men and three women, were identified. Six patients were treated for primary disease, and two were treated for tumor recurrence. The modified Kadish staging was A in one patient (12.5%), B in two patients (25%), C in four patients (50%), and D in one patient (12.5%). All patients had a complete resection with negative intraoperative margins. One patient had intraoperative hypertension; there were no perioperative complications. With a mean follow-up of over 27 months, all patients are without evidence of disease. In addition, we reviewed the literature and identified several overlapping case series of patients with esthesioneuroblastoma treated via a purely endoscopic technique.

Our series adds to the growing experience of expanded endonasal endoscopic surgery in the treatment of skull base tumors including esthesioneuroblastoma. Longer follow-up on a larger number of patients is required to further demonstrate the utility of endoscopic approaches in the management of this malignancy.

An extent of resection threshold for newly diagnosed glioblastomas

J Neurosurg 115:3–8, 2011. DOI: 10.3171/2011.2.JNS10998

The value of extent of resection (EOR) in improving survival in patients with glioblastoma multiforme (GBM) remains controversial. Specifically, it is unclear what proportion of contrast-enhancing tumor must be resected for a survival advantage and how much survival improves beyond this threshold. The authors attempt to define these values for the patient with newly diagnosed GBM in the modern neurosurgical era.

Methods. The authors identified 500 consecutive newly diagnosed patients with supratentorial GBM treated at the University of California, San Francisco between 1997 and 2009. Clinical, radiographic, and outcome parameters were measured for each case, including MR imaging–based volumetric tumor analysis.

Results. The patients had a median age of 60 years and presented with a median Karnofsky Performance Scale (KPS) score of 80. The mean clinical follow-up period was 15.3 months, and no patient was unaccounted for. All patients underwent resection followed by chemotherapy and radiation therapy. The median postoperative tumor volume was 2.3 cm3, equating to a 96% EOR. The median overall survival was 12.2 months. Using Cox proportional hazards analysis, age, KPS score, and EOR were predictive of survival (p < 0.0001). A significant survival advantage was seen with as little as 78% EOR, and stepwise improvement in survival was evident even in the 95%–100% EOR range. A recursive partitioning analysis validated these findings and provided additional risk stratification parameters related to age, EOR, and tumor burden.

Conclusions. For patients with newly diagnosed GBMs, aggressive EOR equates to improvement in overall survival, even at the highest levels of resection. Interestingly, subtotal resections as low as 78% also correspond to a survival benefit.

Quantitative fluorescence in intracranial tumor: implications for ALA-induced PpIX as an intraoperative biomarker

J Neurosurg 115:11–17, 2011. DOI: 10.3171/2011.2.JNS101451

Accurate discrimination between tumor and normal tissue is crucial for optimal tumor resection. Qualitative fluorescence of protoporphyrin IX (PpIX), synthesized endogenously following d-aminolevulinic acid (ALA) administration, has been used for this purpose in high-grade glioma (HGG). The authors show that diagnostically significant but visually imperceptible concentrations of PpIX can be quantitatively measured in vivo and used to discriminate normal from neoplastic brain tissue across a range of tumor histologies.

Methods. The authors studied 14 patients with diagnoses of low-grade glioma (LGG), HGG, meningioma, and metastasis under an institutional review board–approved protocol for fluorescence-guided resection. The primary aim of the study was to compare the diagnostic capabilities of a highly sensitive, spectrally resolved quantitative fluorescence approach to conventional fluorescence imaging for detection of neoplastic tissue in vivo.

Results. A significant difference in the quantitative measurements of PpIX concentration occurred in all tumor groups compared with normal brain tissue. Receiver operating characteristic (ROC) curve analysis of PpIX concentration as a diagnostic variable for detection of neoplastic tissue yielded a classification efficiency of 87% (AUC = 0.95, specificity = 92%, sensitivity = 84%) compared with 66% (AUC = 0.73, specificity = 100%, sensitivity = 47%) for conventional fluorescence imaging (p < 0.0001). More than 81% (57 of 70) of the quantitative fluorescence measurements that were below the threshold of the surgeon’s visual perception were classified correctly in an analysis of all tumors.

Conclusions. These findings are clinically profound because they demonstrate that ALA-induced PpIX is a targeting biomarker for a variety of intracranial tumors beyond HGGs. This study is the first to measure quantitative ALA-induced PpIX concentrations in vivo, and the results have broad implications for guidance during resection of intracranial tumors.

Cytokine networks in glioma

Neurosurg Rev (2011) 34:253–264. DOI 10.1007/s10143-011-0320-y

Glioma is the most frequently occurring brain tumor, but the prognosis of patients with gliomas remains poor despite advances in surgery, radiotherapy, and chemotherapy. Therefore, great efforts have been made to develop improved therapeutic strategies.

Cytokines are a heterogeneous group of soluble small polypeptides or glycoproteins that exert pleiotropic and redundant effects that promote the growth, differentiation, and activation of normal cells. Cytokines have either pro- or anti-inflammatory activity and immunosuppressive activity, depending on the microenvironment surrounding the tumor. The microenvironment consists of heterogeneous tumor cells, immune cells, and extracellular matrix.

Modulation of the microenvironment by the tumor is essential for its growth and progress. Cytokine production acts as a means of communication in the tumor microenvironment.

In this article, we review the cross-talk between cytokines in the tumor microenvironment and the cytokine therapies that have been used till date for glioma treatment.

Lateral Supraorbital Approach Applied to Anterior Clinoidal Meningiomas: Experience With 73 Consecutive Patients

Neurosurgery 68:1632–1647, 2011 DOI: 10.1227/NEU.0b013e318214a840

Anterior clinoidal meningiomas (ACMs) are a subgroup of meningiomas accounting for less than 10% of supratentorial meningiomas.

OBJECTIVE: To assess the reliability and safeness of the lateral supraorbital approach (LSO) to remove ACMs.

METHODS: Between September 1997 and October 2009, a total of 73 ACM patients were operated on at the Department of Neurosurgery, Helsinki University Central Hospital, by the senior author (J.H.). We retrospectively analyzed the clinical data, radiological findings, surgical treatment, histology, and outcome of patients, and discuss the operative technique.

RESULTS: Seventy-three patients were operated on by applying the LSO approach. Apparently complete removal was achieved in 57 patients (78%). Anterior clinoidectomy was performed in 21 cases. Preexisting visual deficit improved in 11 of 39 patients and worsened in 4; 3 had de novo visual deficit. At 3 months after discharge, 60 (82%) patients had a good recovery, 9 (12%) patients were moderately disabled, 1 presented with severe disability, and 3 (4%) patients died of surgery-related causes. Sixteen (22%) patients had residual tumors, 6 of which required reoperation. During the median followup of 36 months (range, 3-146), tumor recurred in 3 patients: 2 were followed-up and 1 was reoperated on.

CONCLUSION: ACMs can be removed via the LSO approach with relatively low morbidity and mortality. Anterior clinoidectomy is required only in selected cases, and we prefer the intradural approach during the LSO approach. High-power coagulation should be avoided in proximity of the optic nerve.

Gamma Knife surgery for parasellar meningiomas: long-term results including complications, predictive factors, and progression-free survival

J Neurosurg 114:1571–1577, 2011. DOI: 10.3171/2011.1.JNS091939

Stereotactic radiosurgery serves as an important primary and adjuvant treatment option for patients with many types of intracranial meningiomas. This is particularly true for patients with parasellar meningiomas. In this study, the authors evaluated the outcomes of Gamma Knife surgery (GKS) used to treat parasellar meningiomas.

Methods. The study is a retrospective review of the outcomes in 138 patients with meningiomas treated at the University of Virginia from 1989 to 2006; all patients had a minimum follow-up of 24 months. There were 31 men and 107 women whose mean age was 54 years (range 19–85 years). Eighty-four patients had previously undergone resection. The mean pre-GKS tumor volume was 7.5 ml (range 0.2–54.8 ml). Clinical and radiographic evaluations were performed, and factors related to favorable outcomes in each case were assessed.

Results. The mean follow-up duration was 84 months (median 75.5 months, range 24–216 months). In 118 patients (86%), the tumor volume was unchanged or had decreased at last follow-up. Kaplan-Meier analysis demonstrated radiographic progression-free survival at 5 and 10 years to be 95.4% and 69%, respectively. Fourteen patients (10%) developed new cranial nerve palsies following GKS. Factors associated with tumor control included younger age, a higher isodose, and smaller tumor volume. A longer follow-up duration was associated with either a decrease or increase in tumor volume. Fourteen patients (10%) experienced new or worsening cranial nerve deficits after treatment. Factors associated with this occurrence were larger pretreatment tumor volume, lower peripheral radiation dose, lower maximum dose, tumor progression, and longer follow-up.

Conclusions. Gamma Knife surgery offers an acceptable rate of tumor control for parasellar meningiomas and accomplishes this with a low incidence of neurological deficits. Radiological control after radiosurgery is more likely in those patients with a smaller tumor volume and a higher prescription dose.

Intraoperative Confocal Microscopy for Brain Tumors: A Feasibility Analysis in Humans

Neurosurgery 68[ONS Suppl 2]:ons282–ons290, 2011. DOI: 10.1227/NEU.0b013e318212464e

The ability to diagnose brain tumors intraoperatively and identify tumor margins during resection could maximize resection and minimize morbidity. Advances in optical imaging enabled production of a handheld intraoperative confocal microscope.

OBJECTIVE: To present a feasibility analysis of the intraoperative confocal microscope for brain tumor resection.

METHODS: Thirty-three patients with brain tumor treated at Barrow Neurological Institute were examined. All patients received an intravenous bolus of sodium fluorescein before confocal imaging with the Optiscan FIVE 1 system probe. Optical biopsies were obtained within each tumor and along the tumor-brain interfaces. Corresponding pathologic specimens were then excised and processed. These data was compared by a neuropathologist to identify the concordance for tumor histology, grade, and margins.

RESULTS: Thirty-one of 33 lesions were tumors (93.9%) and 2 cases were identified as radiation necrosis (6.1%). Of the former, 25 (80.6%) were intra-axial and 6 (19.4%) were extra-axial. Intra-axial tumors were most commonly gliomas and metastases, while all extra-axial tumors were meningiomas. Among high-grade gliomas, vascular neoproliferation, as well as tumor margins, were identifiable using confocal imaging. Meningothelial and fibrous meningiomas were distinct on confocal microcopy—the latter featured spindle-shaped cells distinguishable from adjacent parenchyma. Other tumor histologies correlated well with standard neuropathology tissue preparations.

CONCLUSION: Intraoperative confocal microscopy is a practicable technology for the resection of human brain tumors. Preliminary analysis demonstrates reliability for a variety of lesions in identifying tumor cells and the tumor-brain interface. Further refinement of this technology depends upon the approval of tumor-specific fluorescent contrast agents for human use.

Use of 5-ALA fluorescence guided endoscopic biopsy of a deep-seated primary malignant brain tumor

J Neurosurg 114:1410–1413, 2011. DOI: 10.3171/2010.11.JNS10250

The introduction of fluorescence-guided resection of primary malignant brain tumors was a milestone in neurosurgery. Deep-seated malignant brain tumors are often not approachable for microsurgical resection. For diagnosis and therapy, new strategies are recommended. The combination of endoscopy and 5-aminolevulinic acid–induced protoporphyrin IX (5-ALA-induced Pp IX) fluorescence–guided procedures supported by neuronavigation seems an interesting option. Here the authors report on a combined approach for 5-ALA fluorescence–guided biopsy in which they use an endoscopy system based on an Xe lamp (excitation approximately lambda = 407 nm; dichroic filter system lambda = 380–430 nm) to treat a malignant tumor of the thalamus and perform a ventriculostomy and septostomy. The excitation filter and emission filter are adapted to ensure that the remaining visible blue remission is sufficient to superimpose on or suppress the excited red fluorescence of the endogenous fluorochromes. The authors report that the lesion was easily detectable in the fluorescence mode and that biopsy led to histological diagnosis.

Neurosurgical treatment of craniopharyngioma in adults and children: early and long-term results in a large case series

J Neurosurg 114:1350–1359, 2011.DOI: 10.3171/2010.11.JNS10670

Craniopharyngioma accounts for 2%–5% of all primary intracranial neoplasms. The optimal management of craniopharyngioma remains controversial. The authors evaluated the early results of surgery and the longterm risk of tumor recurrence in a large series of patients undergoing resection of craniopharyngiomas.

Methods. Between 1990 and 2008, 112 consecutive patients (57 male and 55 female patients with a mean [± SEM] age of 33.3 ± 1.8 years) underwent resection of craniopharyngiomas at the authors’ hospital. Recurrence or growth of residual tumor tissue during follow-up was assessed using MR imaging.

Results. There were 3 perioperative deaths (2.7%). Severe adverse events were more frequent in patients who underwent operations via the transcranial route (37%) than the transsphenoidal approach (5.6%; p < 0.001). Magnetic resonance imaging showed radical resection of the tumor in 78 (71.6%) of the remaining 109 patients. Previous surgery and maximum tumor diameter were associated with persistence of disease after surgery. Craniopharyngioma recurred in 26 (24.5%) of 106 patients. Presence of residual tumor on the first postoperative MR imaging, male sex, and no postoperative radiation therapy were associated with a risk of tumor recurrence. Quality-of-life data were assessed in the 91 patients who attended the authors’ institution for follow-up visits. Among them, 8.8% patients were partially or completely dependent on others for daily living activities before surgery. This percentage increased to 14.3% at the last follow-up visit. The 5- and 10-year overall survival rates were 94.4% (95% CI 90.0%–98.8%) and 90.3% (95% CI 83.4%–97.3%), respectively.

Conclusions. Complete surgical removal of craniopharyngioma can be achieved with reasonable safety in more than 70% of patients. Recurrence of craniopharyngioma may occur even after apparent radical excision. Prompt management of residual or recurring disease by radiotherapy, repeat surgery, or a combination of both is usually successful in controlling further tumor growth.

The natural history of intracranial meningiomas

J Neurosurg 114:1250–1256, 2011. DOI: 10.3171/2010.12.JNS101623

Despite the increased detection of incidental or small meningiomas, the lesion’s natural history is largely unknown.

Methods. One year or longer of follow-up was conducted in 244 patients with 273 meningiomas managed conservatively by a single surgeon between 2003 and 2008. Data were stratified according to age, sex, tumor location, symptoms, initial tumor diameter, calcification, MR imaging intensity, and edema. Linear tumor growth was defined as a 2-mm or larger increase in the maximum diameter in any direction of the tumor. Volumetric analysis (ImageJ version 1.43) was also conducted in 154 of 273 meningiomas for which complete radiological data were available in the form of DICOM files throughout the follow-up period. A volume increase greater than 8.2% was regarded as significant because the preliminary volumetry based on 20 randomly selected meningiomas showed that the average SD was 4.1%.

Results. Linear growth was observed in 120 tumors (44.0%) with a mean follow-up of 3.8 years. Factors related to tumor growth were age of 60 or younger (p = 0.0004), absence of calcification (p = 0.027), MR imaging T2 signal hyperintensity (p = 0.021), and edema (p = 0.018). Kaplan-Meier analysis and Cox proportional hazards regression analysis revealed that age 60 or younger (hazard ratio [HR] 1.54, 95% CI 1.05–2.30, p = 0.026), initial tumor diameter greater than 25 mm (HR 2.23, 95% CI 1.44–3.38, p = 0.0004), and the absence of calcification (HR 4.57, 95% CI 2.69–8.20, p < 0.0001) were factors associated with a short time to progression. Volumetric growth was seen in 74.0% of the cases. Factors associated with a higher annual growth rate were male sex (p = 0.0002), initial tumor diameter greater than 25 mm (p < 0.0001), MR imaging T2 signal hyperintensity (p = 0.0001), presence of symptoms (p = 0.037), and edema (p < 0.0001).

Conclusions. Although the authors could obtain variable results depending on the measurement method, the data demonstrate patients younger than 60 years of age and those with meningiomas characterized by hyperintensity on T2-weighted MR imaging, no calcification, diameter greater than 25 mm, and edema need to be observed more closely. Volumetry was more sensitive to detecting tumor growth than measuring the linear diameter.

Gamma Knife surgery of meningiomas located in the posterior fossa: factors predictive of outcome and remission

J Neurosurg 114:1399–1409, 2011. DOI: 10.3171/2010.11.JNS101193

Although numerous studies have analyzed the role of stereotactic radiosurgery for intracranial meningiomas, few studies have assessed outcomes of posterior fossa meningiomas after stereotactic radiosurgery. In this study, the authors evaluate the outcomes of posterior fossa meningiomas treated with Gamma Knife surgery (GKS). The authors also assess factors predictive of new postoperative neurological deficits and tumor progression.

Methods. A retrospective review was performed of a prospectively compiled database documenting the outcomes of 152 patients with posterior fossa meningiomas treated at the University of Virginia from 1990 to 2006. All patients had a minimum follow-up of 24 months. There were 30 males and 122 females, with a median age of 58 years (range 12–82 years). Seventy-five patients were treated with radiosurgery initially, and 77 patients were treated with GKS after resection. Patients were assessed clinically and radiographically at routine intervals following GKS. Factors predictive of new neurological deficit following GKS were assessed via univariate and multivariate analysis, and Kaplan-Meier analysis and Cox multivariate regression analysis were used to assess factors predictive of tumor progression.

Results. Patients had meningiomas centered over the tentorium (35 patients, 23%), cerebellopontine angle (43 patients, 28%), petroclival region (28 patients, 18%), petrous region (6 patients, 4%), and clivus (40 patients, 26%). The median follow-up was 7 years (range 2–16 years). The mean preradiosurgical tumor volume was 5.7 cm3 (range 0.3–33 cm3), and mean postradiosurgical tumor volume was 4.9 cm3 (range 0.1–33 cm3). At last follow-up, 55 patients (36%) displayed no change in tumor volume, 78 (51%) displayed a decrease in volume, and 19 (13%) displayed an increase in volume. Kaplan-Meier analysis demonstrated radiographic progression-free survival at 3, 5, and 10 years to be 98%, 96%, and 78%, respectively. In Cox multivariable analysis, pre-GKS covariates associated with tumor progression included age greater than 65 years (hazard ratio [HR] 3.24, 95% CI 1.12–9.37; p = 0.03) and a low dose to the tumor margin (HR 0.76, 95% CI 0.60–0.97; p = 0.03), and post-GKS covariates included shunt-dependent hydrocephalus (HR 25.0, 95% CI 3.72–100.0; p = 0.001). At last clinical follow-up, 139 patients (91%) demonstrated no change or improvement in their neurological condition, and 13 patients showed symptom deterioration (9%). In multivariate analysis, the only factors predictive of new or worsening symptoms were clival or petrous location (OR 4.0, 95% CI 1.1–13.7; p = 0.03).

Conclusions. Gamma Knife surgery offers an acceptable rate of tumor control for posterior fossa meningiomas and accomplishes this with a low incidence of neurological deficits. In patients selected for GKS, tumor progression is associated with age greater than 65 years and decreasing dose to the tumor margin. Clival- or petrous-based locations are predictive of an increased risk of new or worsening neurological deficit following GKS.

Surgical management and outcome of schwannomas in the craniocervical region

J Neurosurg 114:1257–1267, 2011. DOI: 10.3171/2010.5.JNS0966

Schwannomas occupying the craniocervical junction (CCJ) are rare and usually originate from the jugular foramen, hypoglossal nerves, and C-1 and C-2 nerves. Although they may have different origins, they may share the same symptoms, surgical approaches, and complications. An extension of these lesions along the posterior fossa cisterns, foramina, and spinal canal—usually involving various cranial nerves (CNs) and the vertebral and cerebellar arteries—poses a surgical challenge. The primary goals of both surgical and radiosurgical management of schwannomas in the CCJ are the preservation and restoration of function of the lower CNs, and of hearing and facial nerve function. The origins of schwannomas in the CCJ and their clinical presentation, surgical management, adjuvant stereotactic radiosurgery, and outcomes in 36 patients treated at Barrow Neurological Institute (BNI) are presented.

Methods. Between 1989 and 2009, 36 patients (mean age 43.6 years, range 17–68 years) with craniocervical schwannomas underwent surgical resection at BNI. The records were reviewed retrospectively regarding clinical presentation, radiographic assessment, surgical approaches, adjuvant therapies, and follow-up outcomes.

Results. Headache or neck pain was present in 72.2% of patients. Cranial nerve impairments, mainly involving the vagus nerve, were present in 14 patients (38.9%). Motor deficits were found in 27.8% of the patients. Sixteen tumors were intra- and extradural, 15 were intradural, and 5 were extradural. Gross-total resection was achieved in 25 patients (69.4%). Adjunctive radiosurgery was used in the management of residual tumor in 8 patients; tumor control was ultimately obtained in all cases.

Conclusions. Surgical removal, which is the treatment of choice, is curative when schwannomas in the CCJ are excised completely. The far-lateral approach and its variations are our preferred approaches for managing these lesions. Most common complications involve deficits of the lower CNs, and their early recognition and rehabilitation are needed. Stereotactic radiosurgery, an important tool for the management of these tumors as adjuvant therapy, can help decrease morbidity rates.

Sphenoorbital meningioma: surgical technique and outcome

J Neurosurg 114:1241–1249, 2011.DOI: 10.3171/2010.10.JNS101128

The aim of this study was to describe the surgical technique used for removal of sphenoorbital meningiomas in the authors’ practice and to review the operative outcome.

Methods. Review of the senior author’s practice between 1994 and 2009 revealed 39 patients (mean age 48 years) eligible for this study. Clinical presentation, surgical technique, postoperative outcome, and follow-up data are presented. Surgical technique is detailed, with an emphasis on aggressive removal consisting of drilling of the hypertrophied sphenoid bone, orbital wall, and anterior clinoid process, followed by tumor removal and a wide resection of the involved dura. A simple dural closure without reconstruction of the orbital roof or the lateral wall of the orbit is also described.

Results. Gross-total resection was achieved in 15 cases (38.5%), near-total resection with small residual in the cavernous sinus or periorbita in 20 cases (51.3%), and subtotal resection in 4 cases (10.3%). Postoperative complications included trigeminal hypesthesia in 9 patients, oculomotor palsy in 3 patients, and seizure in 2 patients. Seven patients had recurrence within the mean follow-up period of 40.7 months. Preoperative visual deficits were present in 21 patients (53.8%). Of these, 14 (66.7%) experienced visual recovery to normal levels postoperatively. Statistical analyses revealed preoperative severe visual deficit and sphenoid bone hypertrophy as an independent risk factor and an independent favorable factor, respectively, for a favorable visual outcome. Proptosis was resolved (≤ 2 mm) in 73.5% of the authors’ patients. No patient had postoperative enophthalmos.

Conclusions. In the authors’ practice, surgery for sphenoorbital meningiomas consists of resection of the orbital/ sphenoid intraosseous, intraorbital, and intradural tumor components. The authors believe that aggressive removal of the orbital/sphenoid intraosseous tumor is critical for a favorable visual outcome and tumor control. Furthermore, satisfactory cosmetic results can be achieved with simple reconstruction techniques as described.

Hydrocephalus associated with vestibular schwannomas: management options and factors predicting the outcome

J Neurosurg 114:1209–1215, 2011. DOI: 10.3171/2010.10.JNS1029

The current, generally accepted optimal management for hydrocephalus related to vestibular schwannomas (VSs) is primary tumor removal, with further treatment reserved only for patients who remain symptomatic. Previous studies have shown, however, that this management can lead to an increase in surgery-related complications. In this study, the authors evaluated their experience with the treatment of such patients, with the aim of identifying the following: 1) the parameters correlating to the need for specific hydrocephalus treatment following VS surgery; and 2) patients at risk for developing hydrocephalus-related complications.

Methods. This was a retrospective study of a 400-patient series. The complication rates and outcomes following primary hydrocephalus treatment versus primary VS removal were compared. Patients undergoing primary tumor removal were further subdivided on the basis of the need for subsequent hydrocephalus treatment. The 3 categories of parameters tested for correlation with the need for such subsequent treatment as well as with heightened risk for developing complications were patient-, tumor-, and hydrocephalus-related.

Results. Of the entire series, 53 patients presented with hydrocephalus. Forty-eight of 53 patients underwent primary VS surgery, of whom 42 (87.5%) did not require additional hydrocephalus treatment. Of the 6 patients who did require additional hydrocephalus treatment, only 3 ultimately required a VP shunt. Factors correlating to the need of hydrocephalus treatment after VS removal were large tumor size, irregular tumor surface, and severe preoperative hydrocephalus. Patients with a longer symptom duration prior to surgery, those with polycyclic tumors, or with inhomogeneous VS, were at heightened risk for the development of CSF leaks. The general and functional outcome of surgery showed no correlation to the presence of preoperative hydrocephalus.

Conclusions. Primary tumor removal is the optimum management of disease in patients with VS with associated hydrocephalus; it leads to resolution of the hydrocephalus in the majority of cases, and the outcome is similar to that of patients without hydrocephalus. Certain factors may aid in identifying patients at risk for developing persistent hydrocephalus as well as those at risk for CSF leaks

Are stereotactic sample biopsies still of value in the modern management of pineal region tumours? Lessons from a single-department, retrospective series

Acta Neurochir (2011) 153:1111–1122. DOI 10.1007/s00701-010-0936-7

Recent improvements in imaging-based diagnosis, the broader application of neuroendoscopic techniques and advances in open surgery techniques mean that the need for stereotactic biopsies in the management of pineal region tumours must be reevaluated. The primary aim of this retrospective study was to establish whether stereotactic biopsy is still of value in the modern management of pineal region tumours.

Methods From 1985 to 2009, 88 consecutive patients underwent a stereotactic biopsy in our institution (51 males and 37 females; median age at presentation 30; range 2–74).

Results Accurate tissue diagnoses were obtained in all but one case (i.e. 99%). In one case (1%), three distinct stereotactic procedures were necessary to obtain a tissue diagnosis. There was no mortality or permanent morbidity associated with stereotactic biopsy. One patient (1%) presented an intra-parenchymal hematoma but no related clinical symptoms. Five patients (6%) presented transient morbidity, which lasted for between 2 days and 3 weeks after the biopsy.

Conclusions To guide subsequent treatment, we believe that histological diagnosis is paramount. Stereotactic biopsies are currently the safest and the most efficient way of obtaining this essential information. Recent improvements in stereotactic technology (particularly robotic techniques) appear to be very valuable, with almost no permanent morbidity or mortality risk and no decrease in the accuracy rate. In our opinion, other available neurosurgical techniques (such as endoscopic neurosurgery, stereotactic neurosurgery and open microsurgery) are complementary and not competitive.

Navigated Transcranial Magnetic Stimulation and Functional Magnetic Resonance Imaging: Advanced Adjuncts in Preoperative Planning for Central Region Tumors

Neurosurgery 68:1317–1325, 2011 DOI: 10.1227/NEU.0b013e31820b528c

Tumor resection in the vicinity of the motor cortex poses a challenge to all neurosurgeons. For preoperative assessment of eloquent cortical areas, functional magnetic resonance imaging (fMRI) is used, whereas intraoperatively, direct cortical stimulation (DCS) is performed. Navigated transcranial magnetic stimulation (nTMS) is comparable to DCS in activating cortical pyramidal neurons.

OBJECTIVE: To evaluate the reliability of nTMS compared with fMRI and DCS for preoperative resection planning of centrally located tumors.

METHODS: In a prospective series, 11 patients (ages, 20-63 years; mean, 41.9 ± 14.9 years, 2 women) with tumors located in or adjacent to the motor cortex were evaluated for surgery. fMRI and nTMS were applied for preoperative assessment of the extent of tumor resection. A 3-dimensional anatomic data set with superimposed fMRI data was integrated in the eXimia Navigated Brain Stimulation station for ensuing motor cortex mapping by nTMS. Responses from nTMS were evaluated by electromyographic response. During surgery, the coordinates of each DCS site were unambiguously defined and integrated into neuronavigation. A post hoc comparison of the coordinates of nTMS, fMRI, and DCS was performed.

RESULTS: Distances from nTMS to DCS (10.5 ± 5.67 mm) were significantly smaller than those from fMRI to DCS (15.0 ± 7.6 mm).

CONCLUSION: nTMS anticipates information usually only enabled by DCS and therefore allows surgical planning in eloquent cortex surgery.

Pineal region tumors: an optimal approach for simultaneous endoscopic third ventriculostomy and biopsy

Neurosurg Focus 30 (4):E3, 2011. DOI: 10.3171/2011.2.FOCUS10301

Simultaneous endoscopic third ventriculostomy (ETV) and tumor biopsy is a widely accepted therapeutic and diagnostic procedure for patients with noncommunicating hydrocephalus secondary to a pineal region tumor. Multiple approaches have been advocated, including the use of a steerable fiberoptic or rigid lens endoscope via 1 or 2 trajectories. However, the optimal approach has not been established based on the individual anatomical characteristics of the patient.

 Methods. A retrospective review of patients undergoing simultaneous ETV and tumor biopsy was undertaken. Preoperative MR images were examined to measure the width of the anterior third ventricle and maximal diameters of the tumor, Monro foramen (right), and massa intermedia. The distances between the tumor and massa intermedia, tumor and anterior commissure, midbrain and massa intermedia, and the dorsum sella and anterior commissure were also recorded. Single and dual trajectory approaches were compared using paired t-tests for each parameter.

Results. Over an 8-year interval, 15 patients underwent simultaneous ETV and tumor management. These patients ranged from 6 to 71 years of age (mean 36.7 years); 5 were younger than 18 years of age. Seven were treated using a dual trajectory approach, and 8 were treated using a single trajectory approach. All cases were completed without complications or the need for an additional CSF diversionary procedure within 6 months. The diagnostic yield at biopsy was 86.7%. There were no statistically significant differences between the single and dual trajectory groups for the measured parameters. However, the dual trajectory group demonstrated a larger anterior third ventricular diameter (1.43 vs 1.21 cm, p = 0.29). The single trajectory group trended toward a smaller tumor– anterior commissure interval (2.23 vs 2.51 cm, p = 0.24) and a larger dorsum sella–anterior commissure distance (1.67 vs 1.49 cm, p = 0.28).

Conclusions. These data confirm the safety and diagnostic efficacy of simultaneous ETV and biopsy for tumors of the pineal region. Although no statistically significant differences were seen in the authors’ recorded measurements, several trends suggest a role for a tailored approach to selecting a single or dual trajectory approach when using a rigid endoscope

Neuroendoscopic biopsy of ventricular tumors: a multicentric experience

Neurosurg Focus 30 (4):E2, 2011. DOI: 10.3171/2011.1.FOCUS10326

Although neuroendoscopic biopsy is routinely performed, the safety and validity of this procedure has been studied only in small numbers of patients in single-center reports. The Section of Neuroendoscopy of the Italian Neurosurgical Society invited some of its members to review their own experience, gathering a sufficient number of cases for a wide analysis.

Methods. Retrospective data were collected by 7 centers routinely performing neuroendoscopic biopsies over a period of 10 years. Sixty patients with newly diagnosed intraventricular and paraventricular tumors were included. No patient harboring a colloid cyst was included. Data regarding clinical presentation, neuroimaging findings, operative techniques, pathological diagnosis, postoperative complications, and subsequent therapy were analyzed.

Results. In all patients, a neuroendoscopic tumor biopsy was performed. In 38 patients (64%), obstructive hydrocephalus was present. In addition to the tumor biopsy, 32 patients (53%) underwent endoscopic third ventriculostomy (ETV), and 7 (12%) underwent septum pellucidotomy. Only 2 patients required a ventriculoperitoneal shunt shortly after the endoscopy procedure because ETV was not feasible. The major complication due to the endoscopy procedure was ventricular hemorrhage noted on the postoperative images in 8 cases (13%). Only 2 patients were symptomatic and required medical therapy. Infection occurred in only 1 case, and the other complications were all reversible. In no case did clinically significant sequelae affect the patient’s outcome. Tumor types ranged across the spectrum and included glioma (low- and high-grade [27%]), pure germinoma (15%), pineal parenchymal tumor (12%), primary neuroectodermal tumor (4%), lymphoma (9%), metastasis (4%), craniopharyngioma (6%), and other tumor types (13%). In 10% of patients, the pathological findings were inconclusive. According to diagnosis, specific therapy was performed in 35% of patients: 17% underwent microsurgical removal, and 18% underwent chemotherapy or radiotherapy.

Conclusions. This is one of the largest series confirming the safety and validity of the neuroendoscopic biopsy procedure. Complications were relatively low (about 13%), and they were all reversible. Neuroendoscopic biopsy provided meaningful pathological data in 90% of patients, making subsequent tumor therapy feasible. Cerebrospinal fluid pathways can be restored by ETV or septum pellucidotomy (65%) to control intracranial hypertension. In light of the results obtained, a neuroendoscopic biopsy should be considered a possible alternative to the stereotactic biopsy in the diagnosis and treatment of ventricular or paraventricular tumors. Furthermore, it could be the only surgical procedure necessary for the treatment of selected tumors.

Trigeminal schwannomas: experience with 57 cases and a review of the literature

Neurosurg Rev (2011) 34:159–171. DOI 10.1007/s10143-010-0289-y

Trigeminal schwannoma is a mostly benign tumor that can be cured by complete resection. Over the last few decades, several pioneers have developed surgical approaches enabling the total removal of such tumors.

We analyzed 57 patients who underwent radical surgery, including 45 patients who underwent skull base surgery as their initial treatment, for removal of trigeminal schwannomas. Here, we report the surgical management of these cases. Since 1990, all such patients have been treated using three main types of middle fossa skull base approaches, which minimize the exposure of the brain: the anterior transpetrosal approach, subtemporal interdural approach (Dolenc), or a combination of these approaches.

Before 1990, total tumor removal was achieved in only three of eight patients (38%). After 1990, the tumors were totally removed in 43 patients (90%) and were nearly completely removed in an additional three patients (6%). Among the patients who underwent skull base surgery as their initial treatment, a complete resection was achieved in 93% (42/45 patients) of the cases. However, total surgical removal after surgery and Gamma knife surgery was very difficult because of dense adhesions to the brain stem and cranial nerves. No surgery-related mortalities occurred in this series, and the individual KPS scores were more than 90% among the patients who underwent skull base surgery. No recurrences requiring additional surgery have occurred after an average follow-up period of 4.9 years.

Most of the trigeminal schwannomas could be removed totally and safely during a single operation after the introduction of skull base surgery. Therefore, radiosurgery should not be applied as the treatment of first choice for younger patients. A correct anatomical knowledge is critical for minimizing brain exposure and avoiding surgical complications.