Rheumatoid Meningitis: Diagnostic and Therapeutic Observations.

A 75-year-old female with untreated rheumatoid arthritis presented with two weeks of behavioral changes and cognitive decline. A neurologic examination showed severe encephalopathy, brisk reflexes, and bilateral Babinski sign. A contrast-enhanced brain MRI demonstrated right meningeal enhancement and periventricular white matter disease. A computed tomographic angiogram (CTA) of the head and neck was negative for vasculitis. The cerebrospinal fluid (CSF) demonstrated lymphocytic pleocytosis. The patient's serum rheumatoid factor levels were elevated. A biopsy of the leptomeninges and cortex showed lymphocytic vasculitis of the cortical tissue and patchy lymphoplasmacytic infiltrates of dural small vessels consistent with rheumatoid meningitis. The patient received pulse-dose steroids followed by cyclophosphamide infusions. At her three month follow-up appointment, the patient's mental status had improved mildly. A follow-up brain MRI showed resolution of enhancement, but progression of subcortical bihemispheric white matter disease. Subsequently, the patient developed a respiratory infection and passed away. In rheumatoid arthritis, symptoms of encephalopathy, headaches, seizures, or focal neurologic deficits should raise suspicion for CNS involvement. This potentially treatable disease warrants prompt diagnosis.

Clinical Characteristics and Outcomes of Patients with Intracerebral Hemorrhage after Interhospital Transfer to a Designated Stroke Center.

UNLABELLED: Patients with acute ischemic stroke have improved outcomes when cared for in designated stroke centers (SC), in part due to enhanced thrombolytic use. Whether patients with intracerebral hemorrhage (ICH) also benefit from SC care is unknown. In this study, we compared the clinical characteristics and outcomes of ICH patients who underwent interhospital transfer (IHT) to a Joint Commission (JC) designated SC, to ICH patients who presented directly to the SC's emergency department (ED). METHODS: Patients with ICH admitted between 2006 and 2013 were evaluated. The primary outcome measure was in-hospital death or hospice. RESULTS: Among 760 consecutive admissions for ICH, 321 (42.2%) were IHTs. There has been a 30% annual increase in IHT of ICH patients since 2006. The IHT group was younger (70.26 vs 72.28; P =.055), had lower ICH scores (P = .007), a higher Glasgow Coma Scale (GCS) (P = .037), and lower systolic blood pressure (SBP) (P = .003) than those arriving directly to the ED. Female sex was a predictor of in-hospital mortality (OR = 2.26). CONCLUSION: IHT is increasingly common for patients with ICH. The benefit of transfer remains unclear, as younger, healthier patients were the most likely to be transferred. Comprehensive stroke registries are needed to determine if outcomes differ for ICH patients based on transfer or SC care.

Case report of a de novo brainstem arteriovenous malformation in an 18-year-old male and review of the literature.

De novo intracerebral arteriovenous malformations (AVMs) are exceedingly rare with only seven reported cases in the literature. Although generally considered congenital by nature, the lesions do not manifest themselves clinically until the third or fourth decades of life. However, with the advent of improved imaging modalities and more frequent surveillance, an increasing number of de novo cases are being found challenging the concept AVMs develop in the perinatal/antenatal period. Alternatively, this phenomenon could represent a distinct entity in which lesion development occurs after birth. A PubMed search of "de novo cerebral arteriovenous malformation" was performed in which seven reported cases were found. The mean age at diagnosis was 14.7 years with a mean follow-up imaging study of 5.8 years. Lesion location was supratentorial in all previously described cases. This case involves an 18-year-old male with congenital hydrocephalus and seizures diagnosed at 7 months of age. The patient underwent a ventriculoperitoneal shunt and was followed frequently by a neurologist. The last diagnostic imaging was an unremarkable MRI of the brain at age 12. Seven years later, the patient presented with an intracerebral hemorrhage. A CT angiogram demonstrated a large brainstem AVM with an intraparenchymal hemorrhage and intraventricular extension. This case is unique in that it is the first infratentorial de novo AVM. The congenital nature of AVMs is challenged with the increasingly described series of patients with previously documented normal radiographic imaging. This suggests there may be a subset of patients genetically predisposed to postnatal development of AVMs.

Duplicate Left-Sided Vagus Nerve: Intraoperative Imaging, Management, and Placement.

Introduction Duplicate cranial nerves are fundamentally rare anatomical variants. Few case reports have documented cranial nerve duplication. One previous case report has reported a vagus nerve with a smaller secondary accessory nerve component. We present the first reported case of duplicate vagus nerves identical in size and thickness with otolaryngological diagnostic confirmation. Case Description A 25-year-old woman with seizures refractory to medical management decided to undergo placement of a vagus nerve stimulator. During carotid sheath microdissection, two parallel nerve tracts were identified. The two nerves were identical in size and width. Proximal dissection confirmed that the two nerves were independent of one another and neither was a branching segment. To confirm duplicate vagus nerves, otolaryngology was consulted intraoperatively and the duplicate nerves were verified. The vagus nerve stimulator was placed in typical fashion around the medial nerve. Conclusion This is the first reported case of duplicate vagus nerves identical in size and with confirmation by otolaryngology. The authors would like to highlight the operative management of the vagus nerve stimulator placement as well as integrity of the diagnostic conclusions based on size, further dissection, and specialist consultation.

Impaired attention and network connectivity in childhood absence epilepsy.

Patients with childhood absence epilepsy (CAE) often demonstrate impaired interictal attention, even with control of their seizures. No previous study has investigated the brain networks involved in this impairment. We used the continuous performance task (CPT) of attentional vigilance and the repetitive tapping task (RTT), a control motor task, to examine interictal attention in 26 children with CAE and 22 matched healthy controls. Each subject underwent simultaneous 3T functional magnetic resonance imaging-electroencephalography (fMRI-EEG) and CPT/RTT testing. Areas of activation on fMRI during the CPT task were correlated with behavioral performance and used as seed regions for resting functional connectivity analysis. All behavioral measures reflecting inattention were significantly higher in patients. Correlation analysis revealed that impairment on all measures of inattention on the CPT task was associated with decreased medial frontal cortex (MFC) activation during CPT. In addition, analysis of resting functional connectivity revealed an overall decrease within an 'attention network' in patients relative to controls. Patients demonstrated significantly impaired connectivity between the right anterior insula/frontal operculum (In/FO) and MFC relative to controls. Our results suggest that there is impaired function in an attention network comprising anterior In/FO and MFC in patients with CAE. These findings provide an anatomical and functional basis for impaired interictal attention in CAE, which may allow the development of improved treatments targeted at these networks.

Surgical approaches to hypothalamic hamartomas.

OBJECT: Hypothalamic hamartomas (HHs) are devastating lesions causing refractory epilepsy, rage attacks, social ineptitude, and precocious puberty. Microsurgical and/or endoscopic resection offers an excellent risk/benefit profile for cure or improvement of epilepsy. METHODS: The authors reviewed a prospective database maintained during the first 7 years of the Barrow Hypothalamic Hamartoma program. They describe and illustrate their surgical methods, and they review data from several previous publications regarding surgical outcome. RESULTS: To date, the authors have performed surgery in 165 patients for symptomatic HHs. Patients underwent an endoscopic, transcallosal, or skull base approach, or multiple approaches. Twenty-six patients (15.8%) required more than 1 treatment for their HH. CONCLUSIONS: Microsurgical and endoscopic resection of symptomatic HHs are technically demanding but can be performed safely with excellent results and an acceptable risk profile. Meticulous attention to the subtleties of surgical management helps optimize outcomes.

A Novel Use of Direct Platelet Application During Surgery for Clopidogrel-Associated Intracerebral Hemorrhage.

BACKGROUND: Dual antiplatelet therapy is associated with increased rates of intracerebral hemorrhage, especially in the context of subarachnoid hemorrhage. We present a case of a spontaneous hemorrhage in a patient treated with a Pipeline stent for a ruptured dissecting vertebrobasilar aneurysm and the novel use of direct application of platelets during surgery to control bleeding. CASE DESCRIPTION: A 54-year-old previously healthy woman presented with an intradural right vertebral artery dissection with a ruptured 6-mm pseudoaneurysm. The patient was started on aspirin and clopidogrel and the vessel was reconstructed with 2 Pipeline Embolization Devices. On postbleed day number 14, she became obtunded with a blown right pupil; computed tomography of the head demonstrated a large right temporal intracerebral hematoma. The patient was taken emergently to the operating room for evacuation of the clot. Intraoperatively, satisfactory control of bleeding was not achieved despite transfusing several units of platelets intravenously. Ultimately, a mixture of Floseal and platelets applied directly to the hematoma wall allowed prompt hemostasis. At 3 months the patient was doing extremely well clinically and angiography demonstrated occlusion of the aneurysm. CONCLUSIONS: This is the first reported description of direct application of platelets to achieve intraoperative hemostasis. Platelets are activated by thrombin and collagen and the use of Floseal (a bovine-derived, gelatin matrix and human-derived thrombin) further potentiated the effectiveness of this strategy. With the increased incidence of intracerebral hemorrhage associated with dual antiplatelet therapy, this technique may provide a useful tool in the neurosurgical armamentarium.

Utility of the CO2 laser in the microsurgical resection of cavernous malformations.

OBJECTIVE: The CO2 laser has a long record of use in neurosurgery. However, its utility has been limited by its bulky design and the challenge of using it with the operating microscope. With the development of the OmniGuide fiber, a technology that delivers the beam through flexible hollow-core photonic bandgap mirrors, the laser can now be held and used with greater ease and accuracy. METHODS: We retrospectively analyzed a prospectively maintained database to assess the utility of the laser in 23 consecutive patients (10 male, 13 female; mean age, 40.8 years; range, 9-64 years) with a cavernous malformation treated by the senior author (R.F.S.). RESULTS: Four lesions were located in noneloquent areas, 13 were in the brain stem, four were in the spinal cord, and two were in the thalamus. The usefulness of the laser was rated on a scale of 1 to 5, with 5 defined as "extremely helpful." The mean utility score was 3.5 ± 0.94 (range, 2-5). The laser was judged most useful in creating cortisectomies in eloquent areas and in "shrinking" cavernous malformations away from adjacent hemosiderin-stained tissue. The laser was ineffective against calcification and in obtaining hemostasis. CONCLUSIONS: The CO2 laser is a useful addition to the neurosurgical armamentarium for treating lesions in the brainstem, thalamus, and spinal cord. Its primary utility lies in its ability to create focused cortisectomies safely and to shrink cavernous malformations away from eloquent hemosiderin-stained brain.

Cancer-testis and melanocyte-differentiation antigen expression in malignant glioma and meningioma.

Identification of well-defined glioma-specific antigens is a crucial and necessary step in developing immunotherapy for glioblastoma multiforme (GBM). In this study, we analyzed the composite expression of cancer-testis antigens (CTA) and melanocyte-differentiation antigens (MDA) in malignant glioma tissue and primary glioma cell lines and compared them with normal brain specimens and meningioma. CTA and MDA expression was assessed by the reverse transcription-polymerase chain reaction. The following primers were analyzed for CTA: LAGE-1, NY-ESO-1, MAGE-1, MAGE-3, MAGE-4, MAGE-10, CT-7, CT-10, HOM-MEL 40, BAGE, and SCP-1; and for MDA: tyrosinase, gp100, MELAN-A/MART-1, and TRP-2. The expression level was determined by ethidium bromide-stained agarose gel. Among malignant glioma tissue, the highest CTA and MDA expression rates were found for MAGE-3 (22%), MAGE-1 (16%), CT-7 (11%), gp100 (40%), and TRP-2 (29%). Among primary glioma cell lines, the highest levels of expression were: CT-10 (38%), gp100 (100%), and TRP-2 (31%). NY-ESO-1 was the only CTA demonstrated and seen in 12% of meningioma tissue specimens. TRP-2 and gp100 were expressed in 65% and 38% of meningioma tissue, respectively; gp100 and TRP-2 were expressed in 100% and 50% of meningioma cell lines. Of the nine normal brain specimens, all samples tested positive for TRP-2. All other CTA and MDA tested negative in normal brain. We conclude that CTA and MDA demonstrate low-to-variable levels of expression within GBM. However, two CTA (MAGE-1 and MAGE-3) and one MDA (gp100) may be considered candidate antigens based on their restricted expression in GBM. These results will greatly accelerate the development of novel, specific immunotherapeutic strategies.

Cardiac standstill for cerebral aneurysms in 103 patients: an update on the experience at the Barrow Neurological Institute. Clinical article.

OBJECT: The aim of this study was to clarify the surgical indications, risks, and long-term clinical outcomes associated with the use of deep hypothermic circulatory arrest for the surgical treatment of intracranial aneurysms. METHODS: The authors retrospectively reviewed 105 deep hypothermic circulatory arrest procedures performed in 103 patients (64 females and 39 males, with a mean age of 44.8 years) to treat 104 separate aneurysms. Patients' clinical histories, radiographs, and operative reports were evaluated. There were 97 posterior circulation aneurysms: at the basilar apex in 60 patients, midbasilar artery in 21, vertebrobasilar junction in 11, superior cerebellar artery in 4, and posterior cerebral artery in 1. Seven patients harbored anterior circulation aneurysms. Two additional patients harbored nonaneurysmal lesions. RESULTS: Perioperatively, 14 patients (14%) died. Five patients (5%) were lost to late follow-up. At a mean long-term follow-up of 9.7 years, 65 patients (63%) had the same or a better status after surgical intervention, 10 (10%) were worse, and 9 (9%) had died. There were 19 cases (18%) of permanent or severe complications. The combined rate of permanent treatment-related morbidity and mortality was 32%. The mean late follow-up Glasgow Outcome Scale score was 4, and the annual hemorrhage rate after microsurgical clipping during cardiac standstill was 0.5%/year. Ninety-two percent of patients required no further treatment of their aneurysm at the long-term follow-up. CONCLUSIONS: Cardiac standstill remains an important treatment option for a small subset of complex and giant posterior circulation aneurysms. Compared with the natural history of the disease, the risk associated with this procedure is acceptable.

Endoscopic resection of intrathoracic tumors: experience with and long-term results for 26 patients.

OBJECT: Thoracoscopy may be used in place of thoracotomy to resect intrathoracic neoplasms such as paraspinal neurogenic tumors. Although these tumors are rare, they account for the majority of tumors arising in the posterior mediastinum. METHODS: A database was maintained of all patients undergoing thoracoscopic surgery for tumors. The authors analyzed the presenting symptoms, pathological diagnoses, and outcomes of 26 patients (7 males and 19 females, mean age 37.2 years) who were treated for intrathoracic tumors via thoracoscopy between January 1995 and May 2009. Fourteen patients were diagnosed incidentally (54%). Five patients (19%) presented with dyspnea or shortness of breath, 4 (15%) with pain, 1 (4%) with pneumonia, 1 (4%) with hoarseness, and 1 (4%) with Horner syndrome. RESULTS: Pathology demonstrated schwannomas in 20 patients (77%). Other diagnoses included ganglioneurofibroma, paraganglioma, epithelioid angiosarcoma, benign hemangioma, benign granular cell tumor, and infectious granuloma. One patient required conversion to open thoracotomy due to pleural scarring to the tumor. One underwent initial laminectomy due to intraspinal extension of the tumor. Gross-total resection was obtained in 25 cases (96%). The remaining patient underwent biopsy followed by radiation therapy. The mean surgical time was 2.5 hours, and the mean blood loss was 243 ml. The mean duration of chest tube insertion was 1.3 days, and the mean length of hospital stay was 3.0 days. Cases that were treated in the second half of the cohort were more often diagnosed incidentally, performed in less time, and had less blood loss than those in the first half of the cohort. There was 1 case of permanent treatment-related morbidity (mild Horner syndrome). All previously employed patients were able to return to work (mean clinical follow-up 43 months). There were no recurrences (mean imaging follow-up 54 months). CONCLUSIONS: Endoscopic transthoracic approaches can reduce approach-related soft-tissue morbidity and facilitate recovery by preserving the normal tissues of the chest wall, by avoiding rib retraction and muscle transection, and by reducing postoperative pain. This less invasive approach thus shortens hospital stay and recovery time.

Evaluation of angiographically occult spinal dural arteriovenous fistulae with surgical microscope-integrated intraoperative near-infrared indocyanine green angiography: report of 3 cases.

BACKGROUND: Spinal dural arteriovenous fistulae (dAVFs), are lesions involving an aberrant connection between a radicular feeding artery and the venous system of the spinal cord at the dural sleeve of the nerve root. When rare dAVFs are occult on digitally subtracted catheter-based angiography, they present a diagnostic and therapeutic challenge. OBJECTIVE: We report 3 cases of angiographically occult spinal dAVFs that were evaluated during surgery with indocyanine green (ICG) fluorescent microscope-integrated angiography. METHODS: Three patients with clinical and magnetic resonance imaging features suggestive of a spinal dAVF but no abnormality on digital subtraction angiography underwent surgical exploration with the aid of microscope-integrated ICG videoangiography. RESULTS: In all 3 cases, ICG identified the intradural vein draining the fistula, clearly distinguishing it from an artery or uninvolved medullary vein. CONCLUSION: ICG angiography can rapidly identify a draining vein as it enters the spinal canal even in dAVFs not identifiable on catheter-based digital subtraction angiography.

Biportal thoracoscopic sympathectomy for palmar hyperhidrosis in adolescents.

OBJECT: Palmar, axillary, and plantar hyperhidrosis is often socially, emotionally, and physically disabling for adolescents. The authors report surgical outcomes in all adolescents treated for palmar hyperhidrosis via bilateral thoracoscopic sympathectomy at the Barrow Neurological Institute by the senior author. METHODS: A prospectively maintained database of all adolescent patients undergoing bilateral thoracoscopic sympathectomy between 1998 and 2006 (inclusive) was reviewed. Additional follow-up was obtained as needed in clinic or by phone or written questionnaire. RESULTS: Fifty-four patients (40 females) undergoing bilateral procedures were identified. Their mean age was 15.4 years (range 10-17 years). Average follow-up was 42 weeks (range 0.2-143 weeks). Hyperhidrosis involved the palms alone in 10 patients; the palms and axilla in 6 patients; the palms and plantar surfaces in 17 patients; and the palms, axilla, and plantar surfaces in 21 patients. Palmar hyperhidrosis resolved completely in 98.1% of the patients. Resolution or improvement of symptoms was seen in 96.3% of patients with axillary and 71.1% of those with plantar hyperhidrosis. Hospital stay averaged 0.37 days with 68.5% of patients discharged the day of surgery. One patient experienced brief intraoperative asystole that resolved with medications and had no long-term sequelae. Otherwise, no serious intraoperative complications occurred. No patient required chest tube drainage. The percentage of patients who reported satisfaction and willingness to undergo the procedure again was 98.1%. CONCLUSIONS: Biportal, bilateral thoracoscopic sympathectomy is an effective and low-morbidity treatment for severe palmar, axillary, and plantar hyperhidrosis.

Use of flexible hollow-core CO2 laser in microsurgical resection of CNS lesions: early surgical experience.

INTRODUCTION: The CO2 laser has a long history in both experimental and clinical neurosurgery. However, its use over the past decade has been limited by its cumbersome design and bulky set-up of the micromanipulator. These limitations are amplified when it is used with the operating microscope. These restrictions are addressed by the Omniguide fiber, which delivers the beam through flexible hollow-core photonic bandgap mirror fibers and allows the laser to be wielded like any other surgical instrument. METHODS: The attending neurosurgeon prospectively assessed the usefulness of the laser in its first 45 consecutive uses at our institution based on a scale of 1 to 5. RESULTS: The series included 11 cavernous malformations, 14 meningiomas, 7 ependymomas, 3 metastases, 3 astrocytomas, and 7 miscellaneous lesions. The laser was set up 91 times and used in 45 cases. The Omniguide fiber failed 5 times. No adverse events involving patients or staff were associated with laser use. The mean utility score was 3.7 +/- 0.8 (range, 2-5). The laser was most helpful in debulking fibrous lesions too tough for ultrasonic aspiration and lesions adherent to delicate neurovascular structures. The laser was not helpful with highly vascular tumors. CONCLUSION: In our early experience, the Omniguide laser was very helpful in selected cases in resecting specific types of lesions without complications; we have added the device to our neurosurgical armamentarium.

Endocrinopathy, vision, headache, and recurrence after transsphenoidal surgery for Rathke cleft cysts.

BACKGROUND: Rathke cleft cyst can enlarge and become symptomatic. OBJECTIVE: To review the clinical data and results of all patients treated by the senior author for a Rathke cleft cyst. METHODS: A prospectively maintained surgical database, supplemented with updates from telephone conversations, of all patients presenting to the Barrow Neurological Institute from 1992 to the present was reviewed. RESULTS: Seventy-three patients (17 males, 56 females; mean age, 40 years; range, 5-80 years) underwent 77 resections. The mean length of follow-up was 27 months (range, 0-129 months). Presenting symptoms included headache (75%), followed by endocrinopathy (49%), and visual symptoms (39%). Preoperative chiasmopathy resolved in 75% and improved in 21% of the patients. Patients' preoperative endocrinopathy resolved at various rates, depending on the specific axis (29%-100%). Endocrinopathies were more likely to resolve in females than males. New postoperative endocrinopathies also occurred (0-8%). Headache resolved (68%) or improved (21%) in most patients. No patient had worsened headaches. Eight patients had a recurrence, 4 of whom underwent reoperation. The presence of squamous metaplasia was the only predictor of recurrence. CONCLUSION: Surgical fenestration and/or resection of Rathke cleft cyst via the transsphenoidal approach are a rational choice for surgical management of these lesions when symptomatic. In most cases, visual symptoms and headache can be expected to improve. New persistent endocrine deficits can be expected in a small percentage of patients, but preexisting endocrinopathies resolve in many patients.

Thoracoscopic sympathectomy for hyperhidrosis: analysis of 642 procedures with special attention to Horner's syndrome and compensatory hyperhidrosis.

BACKGROUND: Hyperhidrosis (HH) profoundly affects a patient's well-being. OBJECTIVE: We report indications and outcomes of 322 patients treated for HH via thoracoscopic sympathectomy or sympathotomy at the Barrow Neurological Institute. METHODS: A prospectively maintained database of all patients who underwent sympathectomy or sympathotomy between 1996 and 2008 was examined. Additional follow-up was obtained in clinic, by phone, or by written questionnaire. RESULTS: A total of 322 patients (218 female patients) had thoracoscopic treatment (mean age 27.6 years; range, 10-60 years). Mean follow-up was 8 months. Presentations included HH of the palms (43 patients, 13.4%), axillae (13 patients, 4.0%), craniofacial region (4 patients, 1.2%), or some combination (262 patients, 81.4%). Sympathectomy and sympathotomy were equally effective in relieving HH. Palmar HH resolved in 99.7% of patients. Axillary or craniofacial HH resolved or improved in 89.1% and 100% of cases, respectively. Hospital stay averaged 0.5 days. Ablating the sympathetic chain at T5 increased the incidence of severe compensatory sweating (P = .0078). Sympathectomy was associated with a significantly higher incidence of Horner's syndrome compared with sympathotomy (5% vs 0.9%, P = .0319). Patients reported satisfaction and willingness to undergo the procedure again in 98.1% of cases. CONCLUSION: Thoracoscopic sympathectomy is effective and safe treatment for severe palmar, axillary, and craniofacial HH. Ablating the T5 ganglion tends to increase the severity of compensatory sweating. Sympathectomy led to a higher incidence of ipsilateral Horner's syndrome compared with sympathotomy.

Safety of carotid endarterectomy while on clopidogrel (Plavix). Clinical article.

OBJECT: Many patients undergoing carotid endarterectomy (CEA) regularly take clopidogrel, a permanent platelet inhibitor. The authors sought to determine whether taking clopidogrel in the period before CEA leads to more bleeding or other complications. METHODS: The authors performed a retrospective, institutional review board­approved review of 182 consecutive patients who underwent CEA. Clinical, radiographic, and surgical data were gleaned from hospital and clinic records. Analysis was based on the presence or absence of clopidogrel in patients undergoing CEA and was performed twice by considering clopidogrel use within 8 days and within 5 days of surgery to define the groups. RESULTS: Taking clopidogrel within 8 days before surgery resulted in no statistical increase in any measure of morbidity or death. Taking clopidogrel within 5 days was associated with a small but significant increase in operative blood loss and conservatively managed postoperative neck swelling. No measure of permanent morbidity or death was increased in either clopidogrel group. CONCLUSIONS: Findings in this study support the safety of preoperative clopidogrel in patients undergoing CEA.

Hypofractionated CyberKnife radiosurgery for perichiasmatic pituitary adenomas: early results.

OBJECTIVE: Radiation therapy is recommended for pituitary tumors that are refractory to surgical and medical therapies. The efficacy of single-fraction radiosurgery is established for these lesions, but lesions within 3 mm of the optic pathway cannot be safely treated with doses higher than 8 to 10 Gy. We hypothesized that the optic nerve will tolerate 5 consecutive daily radiosurgery fractions of 500 cGy with effective tumor control. METHODS: We reviewed our first 20 patients with recurrent or residual pituitary adenomas within 3 mm of the optic chiasm treated with the CyberKnife radiosurgery system (Accuray, Inc., Sunnyvale, CA). Tumors were treated with a mean coverage of 97 +/- 2.2% (range, 89.8-99.7%), a mean conformity index of 1.3 +/- 0.2 (range, 1.1-1.6), and a mean treatment isodose line of 74.5 +/- 6.6% (range, 60-86%). The primary end point was an interim analysis of visual preservation, and secondary end points were radiographic and endocrinological tumor control. RESULTS: The mean follow-up period for visual field testing was 26.6 +/- 10.5 months (range, 10.6-41 months). The vision of all 14 patients with intact preoperative vision remained intact. Of the 5 patients with impaired vision, 2 remained stable, and 3 improved. No patient's vision deteriorated. The mean radiographic follow-up was 29.3 +/- 8.6 months (range, 10.2-40.5 months). On magnetic resonance imaging, 12 tumors were stable, 8 were smaller, and none enlarged. CONCLUSION: This preliminary study establishes that the optic nerve and chiasm tolerate CyberKnife hypofractionated radiosurgery of 5 x 500 cGy to perichiasmatic pituitary adenomas. Early data suggest that this dosing paradigm may achieve satisfactory radiographic and endocrinological tumor control for these challenging lesions, but longer follow-up is necessary to confirm these results.

Prospective evaluation of surgical microscope-integrated intraoperative near-infrared indocyanine green angiography during cerebral arteriovenous malformation surgery.

OBJECTIVE: Microscope-integrated indocyanine green (ICG) fluorescence angiography is a novel technique in vascular neurosurgery with potential utility in treating arteriovenous malformations (AVMs). METHODS: We analyzed the application of intraoperative ICG in 10 consecutive AVM surgeries for which surgical video was available. The ability to distinguish AVM vessels (draining veins, feeding and nidal arteries) from each other and from normal vessel was evaluated, and ICG angiographic findings were correlated with intra- and postoperative findings on digital subtraction angiography (DSA). RESULTS: ICG angiography was found to be useful by the surgeon in 9 of 10 patients. In 8 patients, it helped to distinguish AVM vessels. In 3 of 4 patients undergoing a postresection injection, it demonstrated that there was no residual arteriovenous shunting. In 1 patient, it helped to identify a small AVM nidus that was otherwise inapparent within a hematoma. Intraoperative DSA showed residual AVM in 2 of 10 patients requiring further resection of AVM not visualized during surgery. CONCLUSION: Microscope-integrated ICG angiography is a useful tool in AVM surgery. It can be used to distinguish AVM vessels from normal vessels and arteries from veins based on the timing of fluorescence with the dye. Our experience suggests that it is less useful with deep-seated lesions or when AVM vessels are not on the surface. ICG angiography complements rather than replaces DSA.