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Background: Endoscopic endonasal approach (EEA) for skull base surgery (SBS) is a significant modification of the current practice. Methods: We reviewed our experience at the University of Pittsburgh with EEAs for 800 patients from 1998 to July 2007. Results: Modular approaches to multiple pathologies of the skull base were designed totally based on intrinsic anatomy. Stages of training were established based on the level of technical difficulty and potential risk of vascular and neural injury. Five levels were defined in an incremental manner. Conclusions: Practice standardization with modular, incremental training is projected to facilitate the gaining of knowledge and skills to safely master EEAs for SBS in an organized manner. We suggest adherence to the systematic acquisition of endoscopic skills, to work as an integrated team of surgeons and to have a thorough perspective of conventional SBS and endoscopic surgery. Therefore, the choice of approach must be a specific function of the anatomy and pathology rather than the surgeon’s bias or lack of experience with alternative approaches.

Local failure and subsequent neurologic death continue to be problematic for brain metastases resulting from renal cell carcinoma (RCC), which are highly resistant to whole brain radiation therapy. The objective of this single-institution series is to determine the outcomes of patients with RCC brain metastases treated with stereotactic radiosurgery (SRS). Between January 2005 and December 2011, 51 patients with a total of 104 brain metastases from RCC were treated with linac-based SRS. The median age of this cohort was 60 years (range, 39–82) and consisted of 39 males and 12 females. The average size of the target lesion was 1.6 cc (0.2–82.7) of which 97 (93 %) lesions were treated with a single fraction of 14–24 Gy. Median follow-up for this cohort was 37.5 months. The actuarial 6- and 12-month rates of local control were 89 and 80 %, respectively. By Cox regression analysis, volume was the only predictor of local failure (p = 0.04). Overall survival determined from the time of SRS at 6 and 12 months was 56 and 44 %, respectively. Smaller tumor volume was found to be a significant predictor of improved survival (p = 0.01). None of the patients experienced grade 3 or greater acute or late toxicities. SRS for brain metastases from renal cell carcinoma is a safe and effective treatment resulting in a high rate of local control. To our knowledge, this is the first report demonstrating a relationship between smaller tumor volume and improved outcomes.

Local tumor control remains a significant challenge in patients with glioblastoma multiforme (GBM). Despite aggressive radiation therapy approaches, most recurrences are within the high-dose field, limiting the ability to safely re-irradiate recurrence using conventional techniques. Fractionated stereotactic radiosurgery (fSRS) is a technique whose properties make it useful for re-irradiation. We retrospectively reviewed the charts of 14 patients with recurrent GBM treated with salvage radiosurgery. Seven patients were male and seven were female with a median age of 58 (range: 39–76). All patients had prior cranial radiation therapy to a median dose of 60 Gy (58–69). There were 18 lesions treated with a median tumor volume of 6.97 cm3 (0.54–50.0 cm3). fSRS was delivered in 1–3 fractions to a median dose of 24 Gy (18–30 Gy). Median follow-up for the cohort was 8 months (3–22 months). On follow-up MRI, 8 of 18 lesions had a radiographic response. The median time-to-progression following primary irradiation was 8 months (1-28 months) while the median time-to-progression (TTP) following fSRS was 5 months (1–16 months). Median local control following re-irradiation was 5 months and actuarial local control was 21% at 1-year. Overall survival following primary irradiation was 79% at 12 months and 46% at 2 years. Overall survival following re-irradiation was 79% at 6 months and 30% at 1 year. No significant treatment-related toxicity was seen in follow-up. These results indicate that re-irradiation for recurrent GBM using fSRS is well-tolerated and can offer a benefit in terms of progression-free survival (PFS).

Object Image-guided frameless stereotactic techniques provide an alternative to traditional head-frame fixation in the performance of fine-needle biopsies. However, these techniques still require rigid head fixation, usually in the form of a head holder. The authors report on a series of fine-needle biopsies and brain abscess aspirations in which a frameless technique was used with a patient's head supported on a horseshoe headholder. To validate this technique, they performed an in vitro accuracy study. Methods Forty-eight patients underwent fine-needle biopsy of intracranial lesions that ranged in size from 0.9 to more than 107.7 ml; a fiducial-less, frameless, image-guided technique was used without rigid head fixation. In 1 of the 48 patients a cerebral abscess was drained. The accuracy study was performed with a skull phantom that was imaged with a CT scanner and tracked with a registration mask containing light-emitting diodes. The objective was a skin fiducial marker with a 4-mm circular target to accommodate the 2.5-mm biopsy needle. A series of 50 trials was conducted. Results Diagnostic tissue was obtained on the first attempt in 47 of 48 brain biopsy cases. In 2 cases small hemorrhages at the biopsy site were noted as a complication on the postoperative CT scan. One of these hemorrhages resulted in hand and arm weakness. The accuracy study demonstrated a 98% success rate of the biopsy needle passing through the 4-mm circular target using the registration mask as the registration and tracking device. This demonstrates a ± 0.75-mm tolerance on the targeting method. Conclusions The accuracy study demonstrated the ability of the mask to actively track the target and allow navigation to a 4-mm-diameter circular target with a 98% success rate. The frameless, pinless, fiducial-less technique described herein will likely be another safe, fast alternative to frame-based stereotactic techniques for fine-needle biopsy that avoids the potential morbidity of rigid head-pin fixation. Furthermore, it should lend itself to other image-guided applications such as the placement of ventricular catheters for shunting or Ommaya reservoirs.

Purpose A phase I/II trial was performed to evaluate the safety and immunogenicity of a novel vaccination with α-type 1 polarized dendritic cells (αDC1) loaded with synthetic peptides for glioma-associated antigen (GAA) epitopes and administration of polyinosinic-polycytidylic acid [poly(I:C)] stabilized by lysine and carboxymethylcellulose (poly-ICLC) in HLA-A2+ patients with recurrent malignant gliomas. GAAs for these peptides are EphA2, interleukin (IL)-13 receptor-α2, YKL-40, and gp100. Patients and Methods Twenty-two patients (13 with glioblastoma multiforme [GBM], five with anaplastic astrocytoma [AA], three with anaplastic oligodendroglioma [AO], and one with anaplastic oligoastrocytoma [AOA]) received at least one vaccination, and 19 patients received at least four vaccinations at two αDC1 dose levels (1 × or 3 × 107/dose) at 2-week intervals intranodally. Patients also received twice weekly intramuscular injections of 20 μg/kg poly-ICLC. Patients who demonstrated positive radiologic response or stable disease without major adverse events were allowed to receive booster vaccines. T-lymphocyte responses against GAA epitopes were assessed by enzyme-linked immunosorbent spot and HLA-tetramer assays. Results The regimen was well-tolerated. The first four vaccines induced positive immune responses against at least one of the vaccination-targeted GAAs in peripheral blood mononuclear cells in 58% of patients. Peripheral blood samples demonstrated significant upregulation of type 1 cytokines and chemokines, including interferon-α and CXCL10. Nine (four GBM, two AA, two AO, and one AOA) achieved progression-free status lasting at least 12 months. One patient with recurrent GBM demonstrated sustained complete response. IL-12 production levels by αDC1 positively correlated with time to progression. Conclusion These data support safety, immunogenicity, and preliminary clinical activity of poly-ICLC-boosted αDC1-based vaccines.

Removal of excessive mitochondrial reactive oxygen species by electron scavengers and antioxidants is a promising therapeutic strategy to reduce the detrimental effects of radiation exposure. Here we exploited triphenylphosphonium (TPP) cation as a means to target nitroxide radicals to mitochondria. We synthesized a library of TPP-conjugated nitroxides and tested their radioprotective effects in gamma-irradiated mouse embryo cells and human epithelial BEAS-2B cells. Cells were incubated with conjugates either before or after irradiation. We found that [2-(1-oxyl-2,2,6,6-tetramethyl-piperidin-4-ylimino)-ethyl]-triphenyl-phosphonium (TPEY-Tempo) significantly blocked radiation-induced apoptosis as revealed by externalization of phosphatidylserine on the cell surface and inhibition of cytochrome c release from mitochondria. Using electron paramagnetic resonance, we showed that TPEY-Tempo was integrated into cells and mitochondria, where it underwent one-electron reduction to hydroxylamine. TPEY-Tempo acted as an electron scavenger that prevented superoxide generation and cardiolipin oxidation in mitochondria. Finally, TPEY-Tempo increased the clonogenic survival rate of irradiated cells. The cellular integration efficiencies of nonradioprotective TPP conjugates, including Mito-Tempo (Alexis, San Diego, CA), were markedly lower, although these homologues were integrated into isolated succinate-energized mitochondria to a similar extent as TPEY-Tempo. We conclude that mitochondrial targeting of TPP-conjugated nitroxides represents a promising approach for the development of novel radioprotectors.

The authors report the safety and efficacy of using a percutaneous minimal-access insertion technique for distal shunt catheter placement in 100 cases. From June 2007 to March 2008, they attempted 100 minimal-access insertions of distal shunt catheters in 91 patients who required ventriculoperitoneal shunting. Using the minimal-access approach, they avoided utilizing laparoscopic assistance or a mini-laparotomy in 91% of the cases. There were no bowel injuries or misplaced distal catheters. Additional outcomes in terms of operative times, cases that required conversion to open or laparoscopically assisted implantation, and infection rates are presented. They conclude that intraperitoneal shunt catheter placement can be safely and effectively accomplished using a simplified percutaneous minimal-access insertion method that does not require direct laparoscopic visualization.

Hypoxia contributes to the progression of a variety of cancers by activating adaptive transcriptional programs that promote cell survival, motility and tumor angiogenesis. Although the importance of hypoxia and subsequent hypoxia-inducible factor-1alpha (HIF-1alpha) activation in tumor angiogenesis is well known, their role in the regulation of glioma-derived stem cells is unclear. In this study, we show that hypoxia (1% oxygen) promotes the self-renewal capacity of CD133-positive human glioma-derived cancer stem cells (CSCs). Propagation of the glioma-derived CSCs in a hypoxic environment also led to the expansion of cells bearing CXCR4 (CD184), CD44(low) and A2B5 surface markers. The enhanced self-renewal activity of the CD133-positive CSCs in hypoxia was preceded by upregulation of HIF-1alpha. Knockdown of HIF-1alpha abrogated the hypoxia-mediated CD133-positive CSC expansion. Inhibition of the phosphatidylinositol 3-kinase(PI3K)-Akt or ERK1/2 pathway reduced the hypoxia-driven CD133 expansion, suggesting that these signaling cascades may modulate the hypoxic response. Finally, CSCs propagated at hypoxia robustly retained the undifferentiated phenotype, whereas CSCs cultured at normoxia did not. These results suggest that response to hypoxia by CSCs involves the activation of HIF-1alpha to enhance the self-renewal activity of CD133-positive cells and to inhibit the induction of CSC differentiation. This study illustrates the importance of the tumor microenvironment in determining cellular behavior.

Patients with Muir-Torre syndrome, an autosomal-dominant familial tumor condition caused by germline mutation of the DNA mismatch repair genes, MSH2 or MLH1, present with tumors of the sebaceous gland and visceral malignancies characterized by microsatellite instability. Here we show development of glioblastoma multiforme in a patient with Muir-Torre syndrome. Immunohistochemical analysis of the brain tumor and colon cancer revealed loss of the DNA mismatch repair gene detected by the genetic test, suggesting a pathogenic link.

Object The authors introduce a novel technique of intraparenchymal brain tumor resection using a rod lens endoscope and parallel instrumentation via a transparent conduit. Methods Over a 4-year period, 21 patients underwent completely endoscopic removal of a subcortical brain lesion by means of a transparent conduit. Image guidance was used to direct the cannulation and resection of all lesions. Postoperative MR imaging or CT was performed to assess for residual tumor in all patients, and all patients were followed up postoperatively to assess for new neurological deficits or other surgical complications. Results The histopathological findings were as follows: 12 metastases, 5 glioblastomas, 3 cavernous malformations, and 1 hemangioblastoma. Total radiographically confirmed resection was achieved in 8 cases, near-total in 6 cases, and subtotal in 7 cases. There were no perioperative deaths. Complications included 1 infection and 1 pulmonary embolus. There were no postoperative hematomas, no postoperative seizures, and no worsened neurological deficits in the immediate postoperative period. Conclusions Fully endoscopic resection may be a technically feasible method of resection for selected subcortical masses. Further experience with this technique will help to determine its applicability and safety.

Cushing disease (CD) is hypercortisolemia caused by a pituitary tumor. The culprit sellar neoplasm is often too small to detect on neuroimaging, yet its size belies its immense potential morbidity. Modern care of these complex patients demands a dedicated team composed of neurosurgeons, otolaryngolo

Endoscopic endonasal surgery can be applied to the management of benign and malignant sinonasal neoplasms with good results. For tumors that involve the skull base, an endoscopic "craniofacial resection" can be performed with en bloc excision of the involved dura. Preliminary experience with completely endoscopic excision of olfactory neuroblastomas indicates good local control and few complications. Advantages of endoscopic endonasal surgery include improved visualization and decreased morbidity compared to traditional approaches.

✓Craniopharyngiomas have always been an extremely challenging type of tumor to treat. The transsphenoidal route has been used for resection of these lesions since its introduction. The authors present a historical review of the literature from the introduction of the endonasal route for resection of craniopharyngiomas until the present. Abandoned early due to technological limitations, this approach has been expanded both in its application and in its anatomical boundaries with subsequent progressive improvements in outcomes. This expansion has coincided with advances in visualization devices, imaging guidance techniques, and anatomical understanding. The progression from the use of headlights, to microscopy, to endoscopy and fluoroscopy, and finally to modern intraoperative magnetic resonance–guided techniques, combined with collaboration between otolaryngologists and neurosurgeons, has provided the framework for the development of current techniques for the resection of sellar and suprasellar craniopharyngiomas.

Object Craniopharyngiomas are notoriously difficult to treat. Surgeons must weigh the risks of aggressive resection against the long-term challenges of recurrence. Because of their parasellar location, often extending well beyond the sella, these tumors challenge vision and pituitary and hypothalamic function. New techniques are needed to improve outcomes in patients with these tumors while decreasing treatment morbidity. An endoscopic expanded endonasal approach (EEA) is one such technique that warrants understanding and evaluation. The authors explain the techniques and approach used for the endoscopic endonasal resection of suprasellar craniopharyngiomas and introduce a tumor classification scheme. Methods The techniques and approach used for the endoscopic, endonasal resection of suprasellar craniopharyngiomas is explained, including the introduction of a tumor classification scheme. This scheme is helpful for understanding both the appropriate expanded approach as well as relevant involved anatomy. Results The classification scheme divides tumors according to their suprasellar extension: Type I is preinfundibular; Type II is transinfundibular (extending into the stalk); Type III is retroinfundibular, extending behind the gland and stalk, and has 2 subdivisions (IIIa, extending into the third ventricle; and IIIb, extending into the interpeduncular cistern); and Type IV is isolated to the third ventricle and/or optic recess and is not accessible via an endonasal approach. Conclusions The endoscopic EEA requires a thorough understanding of both sinus and skull base anatomy. Moreover, in its application for craniopharyngiomas, an understanding of tumor growth and extension with respect to the optic chiasm and infundibulum is critical to safely approach the lesion via an endonasal route.

Objective The interpeduncular cistern, including the retroinfundibular area, is one of the most challenging regions to approach surgically. The pituitary gland and the infundibulum guard the region when an endonasal route is undertaken. Superior transposition of the pituitary gland and infundibulum is described as a functional means to access this complex region through a fully endoscopic, completely transnasal route. Methods Ten consecutive patients in whom a pituitary transposition was performed during an expanded endonasal approach at the University of Pittsburgh Medical Center for resection of retroinfundibular lesions were reviewed. The series consisted of seven men and three women with a mean age of 44.4 years. Pathology consisted of four craniopharyngiomas, four chordomas, and two petroclival meningiomas. Results Five patients (50%) underwent total resection of the tumor, three patients (30%) underwent near total resection ( > 95% removal), and two patients (20%) had partial resection of petroclival meningiomas with the goal of optic apparatus decompression. All four patients with visual deficits recovered their vision completely. There was no neurological deterioration. Eight patients had normal pituitary function preoperatively, seven of whom (87.5%) had confirmed function preservation postoperatively, with one of these patients experiencing transient diabetes insipidus. The remaining patient with a hypothalamic craniopharyngioma underwent complete resection with obligatory panhypopituitarism and diabetes insipidus. Conclusion Endoscopic endonasal transposition of the pituitary gland and its stalk can provide a valuable corridor to the retroinfundibular space and interpeduncular cistern with pituitary function preservation in the majority of patients. This approach should only be pursued once significant experience with endoscopic endonasal approaches has been acquired.

✓ Cerebrospinal fluid (CSF) leakage following endoscopic endonasal skull base resection can be a significant problem. A method for securing tissue grafts is needed. In this paper the authors used an endonasal suturing device to secure the graft reconstruction following endonasal tumor resection. The U-Clip anastomotic device (Medtronic), developed for cardiovascular anastomoses, was used to secure the tissue graft to native dura. A specialized needle driver and hemoclip applier were used for the application and deployment of this device. No suture tying was necessary, facilitating its endonasal application. The graft was successfully secured in its desired position to native dura by using the U-Clip anastomotic device. The patient did not suffer a postoperative CSF leak, and postoperative imaging and endoscopy revealed that the graft was in a good position. There was no complication from the use of the device. The U-Clip anastomotic device can be used as a suture device during endonasal surgery. It may prevent tissue graft migration and help prevent CSF leakage.

✓ The purpose of this study was to describe the technique used to safely identify the petrous carotid artery during expanded endonasal approaches to the skull base. A series of 20 cadaveric studies was undertaken to isolate the vidian artery and nerve and to use them as landmarks to the petrous internal carotid artery (ICA). Twenty-five consecutive paraclival endoscopic cases were also reviewed to determine the consistency of the vidian artery in vivo as an intraoperative landmark to the ICA. These data were then correlated with results from a separate study in which computed tomography scans from 44 patients were evaluated to delineate the course of the vidian canal and its relationship to the petrous ICA. In all 20 cadaveric dissections and all 25 surgical cases, the vidian artery was consistently identified and could be reliably used as a landmark to the ICA. The correlation between anatomical and clinical data in this paper supports the consistent use of the vidian artery as an important landmark to the petrous ICA.

✓Paraclinoidal aneurysms, especially superior hypophyseal artery (SHA) aneurysms (with medial projection), can be challenging to access via a pterional craniotomy and damage to the optic nerve can occur during surgery. The authors have previously reported on endonasal clipping and aneurysmorrhaphy of a vertebral artery aneurysm following proximal and distal protection of the aneurysm using partial coil embolization. To the best of the authors' knowledge no unprotected aneurysm has been clipped using an endonasal approach. The 56-year-old woman in this report was found to have two unruptured aneurysms: an anterior communicating artery (ACoA) aneurysm and an SHA aneurysm. An endoscopic endonasal, transplanar–transsellar approach was used to successfully clip the SHA aneurysm. Proximal and distal control was obtained endonasally prior to successful clip occlusion of the aneurysm. The ACoA aneurysm was clipped via a pterional craniotomy during the same anesthetic session. This report shows that it is possible to successfully clip a medially projecting, paraclinoidal aneurysm using an endonasal approach. Such cases must be chosen with extreme caution and only performed by surgeons with significant experience with both endoscopic endonasal approaches and neurovascular surgery.

Objectives: The purpose of this study is to describe the anatomy and relationships of the vidian canal to known endonasal and skull base landmarks. This will allow the endoscopic skull base surgeon to safely approach the anterior genu of the potrous carotid artery during expanded endonasal approaches to the skull base. Study Design: The study is a prospective cohort study. Methods: Axial, coronal, and sagittal computed tomography scans of the paranasal sinuses and skull base of 44 patients were examined. Individuals with known skull base pathology were excluded. Measurements induded the length of the vidian canal, the relationship of the vidian canal to the anterior genu of the petrous carotid artery, and the type of pneumatization of the noid sinus as it pertains to foramen rotundum and the vidian canal. In addition, we will focus on the relationship of the vidian canal to the sphenopalatine foramen and base of the medial pterygoid plato. Results: The degree of pneumatization of of the sphenoid sinus is highly variable. The mean length of the vidian canal is 18 mm (10-23 mm). The vidian canal is found entirely within bone in 27% to 30% of scans re viewed. The anterior genu of the petrous internal carotid artery is found superior-medial to the vidian canal in 44 of 44 of the CT scans reviewed. The vidian canal runs medial to lateral in 93% to 98% of patients studied. Couciusions: As a result of this study the endoscopic skull base surgeon has a number of anatomical landmarks and measurements that may be helpful in safely localizing the anterior genu of the petrous internal carotid artery during expanded endonasal approaches to the skull base.

Vascular lesions with an intraosseus nidus involving the skull base are uncommon and challenging [Gianoli GJ, Amedee RG Vascular malformation of the sphenoid sinus. Ear Nose Throat J. 70:373–375;(1991), Malik GM, Mahmood A, Mehta BA Dural arteriovenous malformation of the skull base with intraosseous vascular nidus. Report of two cases. J. Neurosurg 81:620–623;(1994)]. We present a pediatric patient, with a life-threatening arteriovenous malformation (AVM) of the sphenoid sinus, clivus, and ventral skull base, who failed routine multimodality management of AVMs. An entirely transsphenoidal fully endoscopic resection was used to resect this ventral cranial base AVM with an intraosseus nidus located in the clivus. A 4-year-old female presented with recurrent, life-threatening hemorrhages from a clival and ventral skull base AVM of the entire clivus and ventral skull base. The patient had been temporized from the age of 2–4 years with multiple internal and external carotid arterial particulate and alcohol embolizations, including both external and internal carotid artery embolizations, intracranial ligation of the right internal carotid artery, and gamma knife irradiation. Despite these multiple interventions, the patient had persistent, life-threatening hemorrhages from arterial recanalization and recruitment requiring intubation, tracheostomy, and nasopharyngeal packing. The patient underwent a three-stage surgical intervention to resect the AVM. An open subfrontal approach, as the first procedure, provided minimal access to the feeding vessels and was therefore aborted. A two-stage image-guided fully endoscopic approach via a sublabial midface approach without external incisions was performed. Postoperative angiography revealed minimal residual shunting in the pharynx and cavernous sinus. The patient has been free of significant hemorrhages over the past three years. Technological advances in endoscopic surgery and image guidance are now allowing for purely endoscopic surgical treatment of previously unresectable lesions with acceptable morbidity. We report the successful and safe resection of a ventral cranial base AVM via a fully endoscopic approach. This paper reports the first AVM with a purely intraosseus nidus of the ventral skull base and demonstrates the ability to deal with complex ventral skull base lesions using a fully endoscopic transsphenoidal technique.

The expanded endonasal approach provides access to the entire ventral skull base for resection of neoplasms involving the skull base and brain. The creation of large defects of the bone and dura endoscopically presents unique reconstructive challenges. A layered reconstruction of the dura with inlay and onlay fascial grafts covered with fat grafts is an effective technique for repair. An intranasal balloon catheter is used to provide counterpressure in the early phase of healing and a lumbar spinal drain is a useful adjunct in patients at increased risk of a cerebrospinal fluid leak. Vascularized flaps may be necessary in some patients receiving radiation therapy. Continued advances in surgical technology and the introduction of new biomaterials will facilitate the reconstruction of skull base defects following endonasal brain surgery.

Surgical approaches to the petrous apex include transtemporal, middle cranial fossa, and transsphenoidal approaches. Lateral approaches risk brain injury, facial paralysis, and loss of hearing and vestibular function. Recent advances in minimally invasive surgery with the use of intraoperative navigational systems allow transnasal endoscopic access to petrous apex lesions with minimal morbidity. Removing bone medial to the internal carotid artery at the level of the clival recess can drain cholesterol granulomas of the petrous apex. Potential advantages include avoidance of a craniotomy, faster recovery, minimal postoperative symptoms, shorter hospitalization, and improved maintenance of a drainage pathway. This article describes the authors’ technique for endoscopic surgery of the petrous apex (medial approach), and highlights the important anatomic relationships and potential problems of an endoscopic approach.

Since the landmark publication by Ketcham et al in the early 1960s, the resection of sinonasal tumors involving the anterior skull base combines transcranial and transfacial incisions and osteotomies. Recent technical and technologic advances have allowed the use of endoscopic approaches for the resection of these tumors. We report our technique for the endoscopic resection of tumors involving the anterior skull base. Our technique includes the extirpation of select tumors following critical premises, such as obtaining a complete resection and reestablishment of the separation of the sinonasal tract from the cranial cavity. There were 20 patients with various malignant tumors of the sinonasal tract operated on using an endoscopic technique. There are 19 patients alive and without evidence of disease at short-term follow-up (range 11-46 months) The only patient who presented with a recurrent tumor had a sinonasal undifferentiated carcinoma treated with primary chemoradiation. She died of an aggressive recurrence at 8 months postoperatively. In 20 patients, we did not encounter any intraoperative complication. However, postoperative complications included 1 episode of tension pneumocephalus, cerebrospinal fluid leak in 3 patients, and 1 episode of bacterial meningitis associated with a prior cerebrospinal fluid leak. Short-term results suggest that an endoscopic transnasal anterior skull base resection can be performed safely and effectively. Further experience and follow-up are required to ascertain the outcomes of patients treated with endoscopic techniques.

Object Transsphenoidal approaches have been used for a century for the resection of pituitary and other sellar tumors. Recently, however, the standard endonasal approach has been expanded to provide access to other parasellar lesions. With the addition of the endoscope, this expansion has significant potential for the resection of skull base lesions. Methods The anatomical landmarks and surgical techniques used in expanded (extended) endoscopic approaches to the clivus and cervicomedullary junction are reviewed and presented, accompanied by case illustrations of each segment (or module) of approach. The caudal portion of the midline anterior skull base and the cervicomedullary junction is divided into modules of approach: the middle third of the clivus, its lower third, and the cervicomedullary junction. Case illustrations of successful resections of lesions via each module of the approach are presented and discussed. Conclusions Endoscopic expanded endonasal approaches to caudally located midline anterior skull base and cervicomedullary lesions are feasible and hold great potential for decreased morbidity. The effectiveness and appropriate use of these techniques must be evaluated by close examination of outcomes as case series expand.

Object Transsphenoidal approaches have been used for a century for the resection of pituitary and other sellar tumors. More recently, the standard endonasal approach has been expanded to provide access to other, parasellar lesions. With the addition of the endoscope, this expansion carries significant potential for the resection of skull base lesions. Methods The anatomical landmarks and surgical techniques used in expanded (extended) endoscopic approaches to the rostral, anterior skull base are reviewed and presented, accompanied by case illustrations of each segment (or module) of approach. The rostral half of the anterior skull base is divided into modules of approach: sellar/parasellar, transplanum/transtuberculum, and transcribriform. Case illustrations of successful resections of lesions with each module are presented and discussed. Conclusions Endoscopic, expanded endonasal approaches to rostral anterior skull base lesions are feasible and hold great potential for decreased morbidity. The effectiveness and appropriate use of these techniques must be evaluated by close examination of outcomes as case series expand.

Harvey Cushing first popularized the transsphenoidal route to the sella turcica, and Jules Hardy subsequently refined it by adding the operating microscope. Over the ensuing decades, attempts at extending the application of this approach have been advanced by Edward Laws and others. With the evolution of endoscopic approaches, the natural expansion of their use to intradural lesions followed. For the expanded endonasal approach to become a viable option, the paramount concerns surrounding consistent reconstruction of the dura mater must be overcome. In this review the authors chronicle the evolution of the reconstruction technique they currently use after performing expanded endonasal approaches. They also report the use of a balloon stent to buttress the reconstruction and counter the effects of graft migration and cerebrospinal fluid fistula formation. The technique described in this report represents an important step forward in the reconstruction of defects resulting from expanded endonasal approaches.

Object The middle third of the clivus and the region around the petrous internal carotid artery (ICA) is a difficult area of the skull base in terms of access. This is a deep area rich with critical neurovascular structures, which is often host to typical skull base diseases. Expanded endoscopic endonasal approaches offer a potential option for accessing this difficult region. The objective of this paper was to establish the clinical feasibility of gaining access to the paraclival space in the region of the middle third of the clivus, to provide a practical modular and clinically applicable classification, and to describe the relevant critical surgical anatomy for each module. Methods The anatomical organization of the region around the petrous ICA, cavernous sinus, and middle clivus is presented, with approaches divided into zones. In an accompanying paper in this issue by Cavallo, et al., the anatomy of the pterygopalatine fossa is presented; this was observed through cadaveric dissection for which an expanded endonasal approach was used. In the current paper the authors translate the aforementioned anatomical study to provide a clinically applicable categorization of the endonasal approach to the region around the petrous ICA. A series of zones inferior and superior to the petrous ICA are described, with an illustrative case presented for each region. Conclusions The expanded endonasal approach is a feasible approach to the middle third of the clivus, petrous ICA, cavernous sinus, and medial infratemporal fossa in cases in which the lesion is located centrally, with neurovascular structures displaced laterally.

The increasing popularity of minimally invasive neurosurgery has led to the development of transnasal expanded approaches for the treatment of skull base lesions. One of the greatest challenges in safely accomplishing resection of tumors, particularly intradural lesions, is effective hemostasis. Over the past 7 years the authors have progressively developed an organized approach to address this challenge. This has required the development of new instrumentation as well as variations on standard techniques. In this report they present the technique that has evolved at their institution for endoneurosurgical hemostasis.

A fully endoscopic, completely transnasal approach to the jugular foramen has been developed. Technical nuances are discussed outlining the operative technique using this approach to resect a variety of tumors affecting the jugular foramen. An illustrative case of a large recurrent glomus jugulare tumor is used to describe the expanded endoscopic endonasal approach to the jugular foramen. Key anatomic considerations, equipment and patient outcomes are reported. The operative technique is described in stepwise fashion using intraoperative photographs and schematic illustrations. The endoscopic endonasal approach provides complete access to the jugular fossa.

The authors describe the combination of awake craniotomy and minimally invasive endoscopic port surgery to resect a high-grade glioma located near eloquent structures of the temporal lobe. Combined minimally invasive techniques such as these may facilitate deep tumor resection within eloquent regions of the brain, allowing minimum white matter dissection. Technical aspects of this procedure, a case outcome involving this technique, and the direction of further investigations for the utility of these techniques are discussed.

Differentiation of tumor recurrence from radionecrosis is a critical step in the follow-up management of patients treated with stereotactic radiosurgery (SRS) for brain metastases. A method that can reliably differentiate tumor recurrence from radiation necrosis using standard MR sequences would be of significant value.We analyzed the records of 49 patients with 52 brain metastases treated with SRS who subsequently underwent surgical resection of the same lesion. Forty-seven of the lesions had preoperative MRI available for review (90%), including T1 postcontrast, T2, and fluid attenuated inversion recovery sequences. Pre-SRS and preoperative lesion and edema volumes were manually contoured and measured in a blinded fashion using radiation treatment planning software. A neuropathologist analyzed samples for the presence of tumor and/or radiation necrosis.Longer time between SRS and resection (P.001) and a larger edema/lesion volume ratio (high T2/T1c, P = .002) were found to be predictive of radionecrosis as opposed to tumor recurrence. Using a cutoff value of 10 for the edema/lesion volume ratio, we were able to predict the presence of tumor with a positive predictive value of 92%, which increased to 100% when looking only at patients who underwent resection18 months following SRS.On follow-up imaging, lesions with a high edema/lesion volume ratio and lesions that progress later after SRS are more likely to contain radionecrosis. These indices may help guide clinical decision making in the context of evolving lesions after SRS for brain metastases and thereby avoid unnecessary interventions.

Malignant gliomas are lethal cancers in the brain and heavily infiltrated by myeloid cells. Interleukin-4 receptor-α (IL-4Rα) mediates the immunosuppressive functions of myeloid cells, and polymorphisms in the IL-4Rα gene are associated with altered glioma risk and prognosis. In this study, we sought to evaluate a hypothesized causal role for IL-4Rα and myeloid suppressor cells in glioma development. In both mouse de novo gliomas and human glioblastoma cases, IL-4Rα was upregulated on glioma-infiltrating myeloid cells but not in the periphery or in normal brain. Mice genetically deficient for IL-4Rα exhibited a slower growth of glioma associated with reduced production in the glioma microenvironment of arginase, a marker of myeloid suppressor cells, which is critical for their T-cell inhibitory function. Supporting this result, investigations using bone marrow-derived myeloid cells showed that IL-4Rα mediates IL-13–induced production of arginase. Furthermore, glioma-derived myeloid cells suppressed T-cell proliferation in an IL-4Rα–dependent manner, consistent with their identification as myeloid-derived suppressor cells (MDSC). Granulocyte macrophage colony-stimulating factor (GM-CSF) plays a central role for the induction of IL-4Rα expression on myeloid cells, and we found that GM-CSF is upregulated in both human and mouse glioma microenvironments compared with normal brain or peripheral blood samples. Together, our findings establish a GM-CSF–induced mechanism of immunosuppression in the glioma microenvironment via upregulation of IL-4Rα on MDSCs. Cancer Res; 73(21); 6413–23. ©2013 AACR.

Large brain metastases (3 cm) present a therapeutic dilemma, as the dose delivered by stereotactic radiosurgery (SRS) in a single fraction is limited by toxicity to adjacent tissues, resulting in suboptimal local control. This study assessed the efficacy and safety of fractionated SRS for the treatment of large brain metastases.We identified 36 patients with 37 brain metastases treated with fractionated SRS. The median SRS dose was 24 Gy (range, 12 to 27 Gy) in 2 to 5 fractions and the median treatment volume was 15.6 mL (range, 10 to 82.7 mL). Kaplan-Meier analysis was used to estimate local control and overall survival rates.Of the 21 lesions with available radiographic follow-up, 6 lesions (29%) had a documented local failure, yielding an actuarial progression-free survival at 6 and 12 months of 73% and 63%, respectively. The actuarial 6-month and 1-year overall survival rates were 22% and 13%, respectively. No patients in this cohort experienced acute or late complications secondary to SRS.Fractionated SRS is feasible and safe in patients with large brain metastases. Local control rates appear to be improved when compared with that of single fraction SRS with a relative paucity of treatment-related toxicity.

Purpose: To analyze outcomes of reirradiation with stereotactic radiosurgery (SRS) for patients with brain metastases from small cell lung cancer (SCLC). Materials and Methods: We reviewed the clinical outcomes of 27 patients with brain metastases from SCLC treated with CyberKnife® robotic radiosurgery (Accuray Inc., Sunnyvale, CA). Kaplan-Meier analyses were used to estimate local control (LC), intracranial control (IC), and overall survival (OS). The Graded Prognostic Assessment (GPA) prognostic index was determined with a Cox Regression analysis to model predictors of outcome. Results: The median follow-up from SRS was 12 months (2-24 months). Nine patients (32.1%) had Graded Prognostic Assessment (GPA) scores 0-1 and 19 patients (67.9%) had GPA scores 1.5-2.5. 19 patients (70%) received whole brain radiation therapy (WBRT) and 8 patients (30%) received prophylactic cranial irradiation (PCI). The median SRS dose was 20.5 Gy (15-24 Gy) in 1 fraction. Actuarial LC at 6 months and 12 months was 76.5% and 76.5%, respectively. New metastases outside the treated area developed in 60% of assessable patients at a median 3.5 months; 78% received previous WBRT. The median OS was 3 months from SRS with actuarial 6-month and 12-month rates of 25% and 3.6%, respectively. On multivariate analysis no factors were associated with LC, IC, or OS. Conclusions: SRS for reirradiation of brain metastases from SCLC is safe and achieves local tumor control in the majority of patients. Despite SRS, these patients are at high risk of distant brain failure.

Purpose: Melanoma is one of the most common malignancies to metastasize to the brain. Many patients with this disease will succumb to central nervous system (CNS) disease, highlighting the importance of effective local treatment of brain metastases for both palliation and survival of the disease. Our objective was to evaluate the outcomes associated with stereotactic radiosurgery (SRS) in the treatment of melanoma brain metastases. Materials and Methods: We retrospectively reviewed 54 patients with a total of 103 tumors treated with SRS. Twenty patients had prior surgical resection and nine patients underwent prior whole brain radiation therapy (WBRT). 71% of patients had active extracranial disease at the time of SRS. Median number of tumors treated with SRS was 1(range: 1-6) with median radiosurgery tumor volume 2.1 cm 3 (range: 0.05-59.7 cm 3 ). The median dose delivered to the 80% isodose line was 24 Gy in a single fraction. Results: The median follow-up from SRS was five months (range:1-30 months). Sixty-five percent of patients had a follow-up MRI available for review. Actuarial local control at six months and 12 months was 87 and 68%, respectively. Eighty-one percent of patients developed new distant brain metastases at a median time of two months. The six-month and 12-month actuarial overall survival rates were 50 and 25%, respectively. The only significant predictor of overall survival was surgical resection prior to SRS. Post-SRS bleeding occurred in 18% of patients and at a median interval of 1.5 months. There was only one episode of radiation necrosis with no other treatment-related toxicity. Conclusion: SRS for brain metastases from melanoma is safe and achieves acceptable local control.

Objective: We herein report the role of stereotactic radiosurgery (SRS) in the management of symptomatic skull base metastases. Design: This institutional series reviewed 18 consecutive patients with a total of 21 skull base metastases identified between January 2001 and December 2011. Patients/Materials and Methods: The average age of the population was 60.5 years old, presenting on average 4.5 years following initial diagnosis of visceral disease. Most patients presented with symptomatic disease including pain and specific cranial nerve involvement including trigeminal (3), abducens (1), facial (2), and vestibulocochlear (3) nerves. The median treatment volume was 9.7 cc, receiving a median prescribed dose of 20 Gy (range, 15–40 Gy) delivered in 1 to 5 fractions. Results: Of the 18 patients, 10 succumbed to extensive metastatic disease before the first imaging evaluation. Clinical and imaging follow-up was available for the eight remaining patients, of which three had local failure at 1.2, 2.5, and 5.4 months following treatment. In regards to palliation, six of the patients had significant cranial nerve deficits, of which five reported improvement in symptoms. Additionally, all five patients with pretreatment pain reported improvement. At the time of this analysis, 15 of 18 patients have died; however, only one succumbed from progressive CNS disease. One patient reported an increase in paraesthesia and periorbital edema, which improved with a short course of dexamethasone. Conclusions: SRS is a safe and potentially effective treatment for skull base metastases with acceptable rates of local control and palliation of symptoms.

Background Brainstem metastases represent an uncommon clinical presentation that is associated with a poor prognosis. Treatment options are limited given the unacceptable risks associated with surgical resection in this location. However, without local control, symptoms including progressive cranial nerve dysfunction are frequently observed. The objective of this study was to determine the outcomes associated with linear accelerator-based stereotactic radiotherapy or radiosurgery (SRT/SRS) of brainstem metastases. Methods We retrospectively reviewed 38 tumors in 36 patients treated with SRT/SRS between February 2003 and December 2011. Treatment was delivered with the Cyberknife™ or Trilogy™ radiosurgical systems. The median age of patients was 62 (range: 28–89). Primary pathologies included 14 lung, 7 breast, 4 colon and 11 others. Sixteen patients (44%) had received whole brain radiation therapy (WBRT) prior to SRT/SRS; ten had received prior SRT/SRS at a different site (28%). The median tumor volume was 0.94 cm3 (range: 0.01-4.2) with a median prescription dose of 17 Gy (range: 12–24) delivered in 1–5 fractions. Results Median follow-up for the cohort was 3.2 months (range: 0.4-20.6). Nineteen patients (52%) had an MRI follow-up available for review. Of these, one patient experienced local failure corresponding to an actuarial 6-month local control of 93%. Fifteen of the patients with available follow-up imaging (79%) experienced intracranial failure outside of the treatment volume. The median time to distant intracranial failure was 2.1 months. Six of the 15 patients with distant intracranial failure (40%) had received previous WBRT. The actuarial overall survival rates at 6- and 12-months were 27% and 8%, respectively. Predictors of survival included Graded Prognostic Assessment (GPA) score, greater number of treatment fractions, and higher prescription dose. Three patients experienced acute treatment-related toxicity consisting of nausea (n = 1) and headaches (n = 2) that resolved with a short-course of dexamethasone. Conclusion SRT/SRS for brainstem metastases is safe and achieves a high rate of local control. We found higher GPA as well as greater number of treatment fractions and higher prescription dose to be correlated with improved overall survival. Despite this approach, prognosis remains poor and distant intracranial control remains an issue, even in patients previously treated with WBRT.

BACKGROUND: High-definition fiber tracking (HDFT) is a novel combination of processing, reconstruction, and tractography methods that can track white matter fibers from cortex, through complex fiber crossings, to cortical and subcortical targets with subvoxel resolution. OBJECTIVE: To perform neuroanatomical validation of HDFT and to investigate its neurosurgical applications. METHODS: Six neurologically healthy adults and 36 patients with brain lesions were studied. Diffusion spectrum imaging data were reconstructed with a Generalized Q-Ball Imaging approach. Fiber dissection studies were performed in 20 human brains, and selected dissection results were compared with tractography. RESULTS: HDFT provides accurate replication of known neuroanatomical features such as the gyral and sulcal folding patterns, the characteristic shape of the claustrum, the segmentation of the thalamic nuclei, the decussation of the superior cerebellar peduncle, the multiple fiber crossing at the centrum semiovale, the complex angulation of the optic radiations, the terminal arborization of the arcuate tract, and the cortical segmentation of the dorsal Broca area. From a clinical perspective, we show that HDFT provides accurate structural connectivity studies in patients with intracerebral lesions, allowing qualitative and quantitative white matter damage assessment, aiding in understanding lesional patterns of white matter structural injury, and facilitating innovative neurosurgical applications. High-grade gliomas produce significant disruption of fibers, and low-grade gliomas cause fiber displacement. Cavernomas cause both displacement and disruption of fibers. CONCLUSION: Our HDFT approach provides an accurate reconstruction of white matter fiber tracts with unprecedented detail in both the normal and pathological human brain. Further studies to validate the clinical findings are needed.

Esthesioneuroblastomas (ENB) are relatively rare neoplasms accounting for less than 5% of malignant sinus tumors. The presentation, preoperative evaluation, imaging, and staging are described. The roles of endoscopic endonasal resection and the traditional transcranial subfrontal approach are compared. The endoscopic surgical technique is emphasized including postoperative repair. The early outcomes of patients who have undergone this approach as well as the role of adjunctive treatment including radiation therapy are described. Potential complications from CSF leak to infectious to vascular are reviewed.

Over a 10-year interval, major advances in endoscopic technique as well as instrumentation to facilitate the endoscopic endonasal approach (EEA) to the skull base have been reported. The authors descr

Purpose: The aim of this study was to analyze results of stereotactic radiosurgery (SRS) as adjuvant therapy for resected brain metastases. Methods: Medical records of patients treated at a single institution with SRS to the postoperative cavity of brain metastases were retrospectively reviewed. Patients who completed the prescribed SRS regimen following gross-total resection and had no previous whole brain radiotherapy were included in the study. Kaplan-Meier analyses were used to estimate local (LC) and intracranial control (IC), and overall survival (OS) rates. Results: Between April 2005 and July 2010, 77 patients (median age 63 years) with 89 metastases met the inclusion criteria. The median prescription dose was 18 Gy (12–27 Gy) delivered in 1–3 fractions for a median target volume of 7.6 cm3 (0.5–59 cm3). The 6-month, 1-year, and 2-year LC rates were 76.1, 76.1, and 74.3%, respectively. The 6-month, 1-year, and 2-year IC rates were 75.2, 54, and 43.6%, respectively. With a median follow-up of 13.8 months, the median OS was 14.5 months (1.9–51.4 months) after SRS. The overall 6-month, 1-year, and 2-year OS rates were 91, 62.5, and 43.6%, respectively. Complications included 2 patients with radiation necrosis. Conclusion: Adjuvant radiosurgery to the tumor cavity of resected brain metastases is well-tolerated and achieves LC in the majority of patients.

Stereotactic radiosurgery (SRS) is a highly specialized type of external beam radiation treatment in which a precise and conformal, image-guided focus of ionizing radiation is delivered to a well-defined target volume in a single procedure. The origins of radiosurgery date back to the 1960s and the use of cobalt based techniques. Over the past 10–15 years, linear accelerators have been designed to allow for the delivery of radiosurgery as well. Robotic radiosurgery couples a linear accelerator to a robotic articulated manipulator which allows for the delivery of both SRS and fractionated SRS (also referred to as stereotactic body radiation therapy (SBRT)). In addition, since frameless techniques are most often employed with robotic radiosurgery, areas outside the cranium can now be treated with similar accuracy. Robotic radiosurgery is currently being used to treat targets located in the brain, spine, head and neck, lung, liver, pancreas, prostate amongst others. This chapter provides the background and technical details of robotic radiosurgery, as well as the current evidence for treatment of various body sites.

The CyberKnife® is a linear accelerator (linac) based platform that utilizes a robotic delivery system that is coupled with real-time imaging to track and compensate for patient or target motion. Evolution of this technology has compensated for respiratory movements with XsightTM lung and has the ability to utilize skeletal tracking. These advances have allowed for the expansion from intra cranial SRS to multisystem SBRT.

Endoscopic endonasal surgery (EES) has been shown to be a feasible approach to cranial base tumors while reducing post-operative morbidity. Using the endoscopic endonasal approach alone or in combination with open approaches may provide advantages over conventional approaches. However, the balance between maximal resection and minimal injury to neurovascular structures frequently precludes gross total resection (GTR). Consequently, adjuvant radiation therapy may be an important option to improve local control (LC) of residual disease. In this retrospective series, we report clinical outcomes, morbidity, and LC of 40 patients with cranial base tumors treated with EES +/- combined open approach followed by fSRS (CyberKnife, Accuray Inc.). 26 patients had benign disease, 7 had newly diagnosed malignant disease, and 7 had previously resected malignant disease. Surgical outcomes were evaluable in all patients. LC after fSRS was evaluable in 39 patients and defined as no evidence of regrowth by MRI, CT, & physical examination. GTR was achieved in 12/40. Median post-operative length of stay (LOS) was 3 days. In multivariable analysis controlling for anatomic location and malignant histology, post-operative complications (n = 10) were significantly associated with patients having combined open and EES (p < 0.01, OR = 16.9). SRS was delivered in 1–5 sessions to a median marginal dose of 24.9 Gy. Median follow-up was 24.7 months (range, 1.5 to 61 months). LC was achieved in 89.7% (35/39) of evaluable patients. LC was achieved in 11/12 patients who had GTR. Median progression-free survival was 19.7 months (21.0 months for benign tumors (n = 26), 5.8 months for previously resected malignant disease (n = 7), and 21.2 months for newly diagnosed malignant disease (n = 7). Of the 31 patients who had symptomatic disease at presentation, 18 (58%) reported complete symptom resolution, 9 partial, and 4 no improvement. One patient who received two prior courses of radiation therapy developed osteosclerosis (grade III). Other adverse events were erythema (grade I, n = 5), nausea (grade II, n = 2), conjunctivitis (grade II, n = 1). EES followed by fSRS is a safe and effective management strategy for selected cranial base tumors. EES combined with an open surgical approach may result in increased complications. However, initial follow-up offers encouraging results indicating shorter time to recovery, acceptable LC rates compared to conventional approaches, and similar median time to progression for benign and newly diagnosed malignant disease.

Since the development of the Radiation Therapy Oncology Group-Recursive Partitioning Analysis (RTOG-RPA) risk classes for high-grade glioma, radiation therapy in combination with temozolomide (TMZ) has become standard care. While this combination has improved survival, the prognosis remains poor in the majority of patients. Therefore, strong interest in high-grade gliomas from basic research to clinical trials persists. We sought to evaluate whether the current RTOG-RPA retains prognostic significance in the TMZ era or alternatively, if modifications better prognosticate the optimal selection of patients with similar baseline prognosis for future clinical protocols. The records of 159 patients with newly-diagnosed glioblastoma (GBM, WHO grade IV) or anaplastic astrocytoma (AA, WHO grade III) were reviewed. Patients were treated with intensity-modulated radiation therapy (IMRT) and concurrent followed by adjuvant TMZ (n = 154) or adjuvant TMZ only (n = 5). The primary endpoint was overall survival. Three separate analyses were performed: (1) application of RTOG-RPA to the study cohort and calculation of subsequent survival curves, (2) fit a new tree model with the same predictors in RTOG-RPA, and (3) fit a new tree model with an expanded predictor set. All analyses used a regression tree analysis with a survival outcome fit to formulate new risk classes. Overall median survival was 14.9 months. Using the RTOG-RPA, the six classes retained their relative prognostic significance and overall ordering, with the corresponding survival distributions significantly different from each other (P

Image-guided frameless stereotactic techniques provide an alternative to traditional head-frame fixation in the performance of fine-needle biopsies. However, these techniques still require rigid head fixation, usually in the form of a head holder. The authors report on a series of fine-needle biopsies and brain abscess aspirations in which a frameless technique was used with a patient's head supported on a horseshoe headholder. To validate this technique, they performed an in vitro accuracy study.Forty-eight patients underwent fine-needle biopsy of intracranial lesions that ranged in size from 0.9 to more than 107.7 ml; a fiducial-less, frameless, image-guided technique was used without rigid head fixation. In 1 of the 48 patients a cerebral abscess was drained. The accuracy study was performed with a skull phantom that was imaged with a CT scanner and tracked with a registration mask containing light-emitting diodes. The objective was a skin fiducial marker with a 4-mm circular target to accommodate the 2.5-mm biopsy needle. A series of 50 trials was conducted.Diagnostic tissue was obtained on the first attempt in 47 of 48 brain biopsy cases. In 2 cases small hemorrhages at the biopsy site were noted as a complication on the postoperative CT scan. One of these hemorrhages resulted in hand and arm weakness. The accuracy study demonstrated a 98% success rate of the biopsy needle passing through the 4-mm circular target using the registration mask as the registration and tracking device. This demonstrates a ± 0.75-mm tolerance on the targeting method.The accuracy study demonstrated the ability of the mask to actively track the target and allow navigation to a 4-mm-diameter circular target with a 98% success rate. The frameless, pinless, fiducial-less technique described herein will likely be another safe, fast alternative to frame-based stereotactic techniques for fine-needle biopsy that avoids the potential morbidity of rigid head-pin fixation. Furthermore, it should lend itself to other image-guided applications such as the placement of ventricular catheters for shunting or Ommaya reservoirs.

Neurosurgery case review : , Neurosurgery case review : , کتابخانه دیجیتال جندی شاپور اهواز

Post-operative radiation and chemotherapy following diagnosis of astrocytoma are standard care. No research has examined racial or insurance-based disparities in treatment receipt. The purpose of this study was to evaluate whether African Americans and patients with dual eligibility in Medicare and Medicaid (DE), compared to Caucasians and patients with Medicare alone, experienced differences in (1) seeing a radiation oncologist, (2) receiving radiation or chemotherapy, and (3) overall survival. Using a retrospective descriptive design, statewide Medicaid and Medicare data were merged with the Michigan Tumor Registry to extract a sample of patients (n = 604) ≥ 65 years old with a first primary astrocytoma diagnosis in Michigan between 1996 and 2000. There were no racial or insurance-based differences in reporting a claim for a radiation oncologist. Controlling for age, income, surgical intervention, residence population, comorbidities, gender, and stage, African Americans were less likely to report radiation claims than Caucasians (OR = 0.20; 95% CI = 0.07-0.54). DE patients were less likely to report radiation claims (OR = 0.50; 95% CI = 0.26-0.94) than those with Medicare only. These differences were not seen with chemotherapy. When only those with a glioblastoma multiforme were examined, DE patients (OR = 0.47; 95% CI = 0.24-0.92) and African Americans (OR = 0.13; 95% CI = 0.04-0.44) were much less likely to report radiation claims. Race and insurance status did not significantly affect survival, although income did. Data suggest disparities in race and insurance status may exist in receiving standard of care for astrocytomas. Further research is warranted to replicate the data and determine potential sources for these disparities.