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Study objective Acute chest syndrome is a leading cause of mortality in patients with sickle cell disease (SCD). Because early detection of acute chest syndrome is directly tied to prognosis, young patients with SCD undergo countless chest radiography screenings throughout their lifetime for commonly occurring acute chest syndrome risk factors such as fever, chest pain, or cough. Chest radiography is not an ideal screening method because it is associated with radiation exposure, which accumulates with repeated imaging. Point-of-care lung ultrasonography is a nonradiating imaging modality that has been used to identify other lung pathology and may have a role in SCD. The goal of this study was to determine the accuracy of point-of-care lung ultrasound to identify an infiltrate suggestive of acute chest syndrome in patients with SCD compared to chest radiography as the gold standard. Methods This was a prospective observational study in 2 urban pediatric emergency departments to evaluate the accuracy of point-of-care lung ultrasonography in identifying patients with SCD who were aged 0 to 21 years and had an infiltrate suggestive of acute chest syndrome compared with chest radiography. Clinicians and trainees with point-of-care lung ultrasonographic training obtained informed consent and performed investigational point-of-care lung ultrasonography to evaluate for lung consolidation. A blinded point-of-care lung ultrasonographic expert reviewed results for quality assurance and agreement. Accuracy, sensitivity, specificity, likelihood ratios, and positive and negative predictive value were calculated for point-of-care lung ultrasonography test performance characteristics, with chest radiography as a reference standard. Results Point-of-care lung ultrasonography was performed on 191 SCD patients with a mean age of 8 years; 41% were female patients, and there was a 17% prevalence of acute chest syndrome. Accuracy of point-of-care lung ultrasonography to detected acute chest syndrome was 92%, sensitivity was 88%, and specificity was 93% compared with that for chest radiography. Conclusion Point-of-care lung ultrasonography is a feasible alternative to chest radiography for screening for acute chest syndrome in young patients with SCD. Further studies are needed to determine how this test performs within clinical practice.

Pleural effusions are common in patients with advanced carcioma, particularly of the lung and breast. While the spinal column ies adjacent to the pleura, to our knowledge there is no reported ase of a pleural effusion causing cord compression. The epidural pace is normally isolated from the pleural space by the parietal leura, spinal column, ribs, and associated soft tissue. Here we describe a patient with lung carcinoma and a prior horacic laminectomy for epidural metastasis who presented with ecurrent cord compression. She was found to have a large epidural uid collection in the region of the prior laminectomy, as well as large pleural effusion which had developed simultaneously. The pidural collection was thin in consistency and under high pressure, onsistent with pleural fluid. The pleural effusion became smaller fter drainage of the epidural collection, suggesting the presence f a pleural–epidural fistula.

Object The 2 aims of this study were as follows: 1) to establish outcome measures of nerve regeneration in an axolotl model of peripheral nerve injury; and 2) to define the timing and completeness of reinnervation in the axolotl following different types of sciatic nerve injury. Methods The sciatic nerves in 36 axolotls were exposed bilaterally in 3 groups containing 12 animals each: Group 1, left side sham, right side crush; Group 2, left side sham, right side nerve resected and proximal stump buried; and Group 3 left side cut and sutured, right side cut and sutured with tibial and peroneal divisions reversed. Outcome measures included the following: 1) an axolotl sciatic functional index (ASFI) derived from video swim analysis; 2) motor latencies; and 3) MR imaging evaluation of nerve and muscle edema. Results For crush injuries, the ASFI returned to baseline by 2 weeks, as did MR imaging parameters and motor latencies. For buried nerves, the ASFI returned to 20% below baseline by 8 weeks, with motor evoked potentials present. On MR imaging, nerve edema peaked at 3 days postintervention and gradually normalized over 12 weeks, whereas muscle denervation was present until a gradual decrease was seen between 4 and 12 weeks. For cut nerves, the ASFI returned to 20% below baseline by Week 4, where it plateaued. Motor evoked potentials were observed at 2–4 weeks, but with an increased latency until Week 6, and MR imaging analysis revealed muscle denervation for 4 weeks. Conclusions Multiple outcome measures in which an axolotl model of peripheral nerve injury is used have been established. Based on historical controls, recovery after nerve injury appears to occur earlier and is more complete than in rodents. Further investigation using this model as a successful “blueprint” for nerve regeneration in humans is warranted.

OBJECTIVE: Using the sequential inflation of 2 sphygmomanometers, Lewis et al. (Heart 16:1-32, 1931) concluded that compressive neuropathy was secondary to ischemia of the compressed nerve segment. Despite subsequent animal studies demonstrating that compressive lesions are more likely the result of mechanical nerve deformation, disagreement remains as to the etiology of rapidly reversible compressive neuropathy. Our hypothesis is that, during the classic sphygmomanometer experiments, the areas of nerve compression at the cuff margins overlapped, so that a region of transient nerve deformation persisted during the second cuff inflation. If true, the original results by Lewis et al. would be consistent with a mechanical pathogenesis. METHODS: In our study, 6 patients underwent sequential upper extremity dual - sphygmomanometer inflation with serial assessment by grip-dynamometer and 2-point discrimination. The order of cuff inflation, as well as the distance between cuffs, was varied. Mean grip force and 2-point discrimination values were statistically compared between conditions. RESULTS: Patients with overlapping cuffs maintained their neurological deficits, whereas those with separated cuffs experienced an improvement in both grip force (P = 0.02) and 2-point discrimination (P < 0.001) when cuff inflation was switched. CONCLUSION: Rapidly reversible compressive neuropathy seems to be secondary to mechanical nerve deformation at the margins of the compressive force rather than the result of ischemia of the compressed nerve segment. Overlap of the mechanically deformed nerve segments likely explains why neurological deficits persisted despite sequential cuff inflation in the classic experiments by Lewis et al.

Object The authors describe their experience in a series of cases of intraneural ganglia within the hip and pelvic regions, and explain the mechanism of formation and propagation of this pathological entity. Methods Five patients with 6 intraneural ganglia are presented. Four patients presented with symptomatic intraneural ganglia in the buttock and pelvis affecting the sciatic and lumbosacral plexus elements. An asymptomatic cyst affecting the opposite sciatic nerve was found on MR imaging in 1 patient. The fifth patient, previously reported on by another group, had an obturator intraneural ganglion that the authors reinterpreted. Results All 5 intraneural ganglia affecting the sciatic and lumbosacral plexus elements were found to have a joint connection to the posteromedial aspect of the hip joint; the obturator intraneural cyst had a joint connection to the anteromedial aspect of the hip joint. In all cases, initial review of the MR images led to their misinterpretation. Conclusions To the authors' knowledge, these are the first cases of intraneural ganglia demonstrated to have a connection to the hip joint. This finding at a rare site provides further evidence for the unifying articular (synovial) theory for the formation of intraneural ganglia and reveals a shared mechanism for their propagation. Furthermore, understanding the pathogenesis of these lesions provides insight into their successful treatment and their recurrence.

Peripheral nerve regeneration research has unfolded a wealth of basic science knowledge in the last century. Today, that knowledge has become the fundamental groundwork for evolving clinical applications to treat peripheral nerve defects. This article discusses two clinical applications that have been investigated thoroughly in the laboratory setting for decades and recently tested in the clinical setting: nerve allotransplantation to graft nerve defects, and brief electrical stimulation to promote nerve regeneration. It also discusses the generation of Thy-1-XFP transgenic mice, which express fluorescent proteins in the nervous system and provide new avenues for investigating peripheral nerve regeneration.

OBJECTIVE: Current management of severe brachial plexus injury has undergone recent modifications, and surgical options have expanded. METHODS: The case of a man with a severe closed brachial plexus injury resulting from a motorcycle accident is presented. The patient is found to have upper root avulsions that deprive him of function in the proximal arm. RESULTS: Pre-, intra-, and postoperative decision making is reviewed by an expert in peripheral nerve surgery. Attention is paid to both diagnosis and management. A brief review of the literature pertaining to these points follows. CONCLUSION: The recent expansion of surgical options for the management of severe brachial plexus injury has introduced significant controversy into this field.

OBJECTIVE On the basis of contemporary multiplanar imaging, microsurgical observations, and long-term follow-up in 60 consecutive patients with sphenoid ridge meningiomas, we propose a modification to Cushing's classification of these tumors. This article will concentrate on patients from this series with global medial sphenoid ridge tumors. METHODS Data were collected prospectively for 35 patients with global meningiomas arising from the medial portion of the sphenoid ridge that were surgically treated between 1982 and 2002. RESULTS All patients were followed for the entire length of this study (mean, 12.8 yr). The tumor size ranged from 2 to 8 cm (mean, 4.5 cm). Of the 24 patients with purely intradural tumors, four (17%) had Simpson Grade I and 19 had Simpson Grade II resections; 23 (96%) had gross total resections. Of the 11 patients with tumors extending extradurally (i.e., cavernous sinus), one (9%) patient had a Simpson Grade II resection, whereas nine (82%) had Simpson Grade III resections, with the latter being all visible tumor removed except that in the cavernous sinus. One (9%) of these 11 patients had a gross total resection, and 9 (82%) had radical resections, with the latter defined as total removal of all intradural tumor. The overall morbidity rate was 18%. There was no surgical mortality or symptomatic cerebral infarction. CONCLUSION An accurate classification of global medial sphenoid meningiomas is mandatory to gain insight into their clinical behavior and for understanding the long-term efficacy and safety of available treatment options. Primary medial sphenoid ridge tumors consistently involve the unilateral arteries of the anterior cerebral circulation, and therefore, the resection of tumor from around these arteries is the most important operative nuance for their safe excision.

Object. The goal of this study is to report the incidence and clinical evolution of neurological deficits in patients who underwent resection of gliomas confined to the parietal lobe. Methods. Patient demographics, findings of serial neurological examinations, tumor location and neuroimaging characteristics, extent of resection, and surgical outcomes were tabulated by reviewing inpatient and office records, as well as all pre- and postoperative magnetic resonance (MR) images obtained in 28 consecutive patients who underwent resection of a glial neoplasm found on imaging studies to be confined to the parietal lobe. Neurological deficits were correlated with hemispheric dominance, location of the lesion within the superior or inferior parietal lobules, subcortical extension, and involvement of the postcentral gyrus. The tumors were located in the dominant hemisphere in 18 patients (64%); had a mean diameter of 39 mm (range 14–69 mm); were isolated to the superior parietal lobule in six patients (21%) and to the inferior parietal lobule in eight patients (29%); and involved both lobules in 14 patients (50%). Gross-total resection, documented by MR imaging, was achieved in 24 patients (86%). Postoperatively, nine patients (32%) experienced new neurological deficits, whereas seven (25%) had an improvement in their preoperative deficit. A correlation was noted between larger tumors and the presence of neurological deficits both before and after resection. Postoperatively higher-level (association) parietal deficits were noted only in patients with tumors involving both the superior and inferior parietal lobules in the dominant hemisphere. At the 3-month follow-up examination, five of nine new postoperative deficits had resolved. Conclusions. Neurological deterioration and improvement occur after resection of parietal lobe gliomas. Parietal lobe association deficits, specifically the components of Gerstmann syndrome, are mostly associated with large tumors that involve both the superior and inferior parietal lobules of the dominant hemisphere. New hemineglect or sensory extinction was not noted in any patient following resection of lesions located in the nondominant hemisphere. Nevertheless, primary parietal lobe deficits (for example, a visual field loss or cortical sensory syndrome) occurred in patients regardless of hemispheric dominance.

THE ANTERIOR SURGICAL APPROACH to the cervical spine in patients with discogenic compressive pathological findings causing radiculopathy or myelopathy is a commonly performed operation with several technical variations. We describe the normal and pathological anatomy and the techniques of surgical decompression of the dura with autograft fusion, which we have used for the past 35 years.

Despite being the foundation of, or supplement to, many skull base exposures, the retrolabyrinthine approach has not been adequately illustrated in the skull base literature. As an aid to skull base surgeons in training, this article provides a step-by-step description of the microsurgical anatomy and operative nuances of this important technique.

The pathogenesis of dural arteriovenous fistulas (DAVFs) is currently unknown, with multiple DAVFs being rare. For patients with limited venous access secondary to sinus thrombosis, or for patients where parent sinus occlusion would not be tolerated, transvenous embolization may not be possible and other treatment methods must be considered. A 69-year-old female patient with a two-year history of progressive headaches, memory loss, and unsteady gait underwent cerebral angiography that revealed three separate DAVFs with congested cortical venous drainage overlying both frontal lobes. Using an application of a transarterial wedged-catheter, flow-arrest technique, N-butyl cyanoacrylate was deposited across all three pathologic arteriovenous connections providing a definitive cure. Transarterial NBCA embolization may provide curative treatment of DAVFs, and is of particular utility in situations where access to the draining venous structures is limited.

Object. The goal of this study was to determine the relationship between aneurysm size and the volume of subarachnoid hemorrhage (SAH). Methods. One hundred consecutive patients who presented with acute SAH, which was diagnosed on the basis of a computerized tomography (CT) scan within 24 hours postictus and, subsequently, confirmed to be aneurysmal in origin by catheter angiography, were included in this study. The data were collected prospectively in 32 patients and retrospectively in 68. The volume of SAH on the admission CT scan was scored in a semiquantitative manner from 0 to 30, according to a previously published method. The mean aneurysm size was 8.3 mm (range 1–25 mm). The mean SAH volume score was 15 (range 0–30). Regression analysis revealed that a smaller aneurysm size correlated with a more extensive SAH (r2 = 0.23, p < 0.0001). Other variables including patient sex and age, intraparenchymal or intraventricular hemorrhage, multiple aneurysms, history of hypertension, and aneurysm location were not statistically associated with a larger volume of SAH. Conclusions. Smaller cerebral aneurysm size is associated with a larger volume of SAH. The pathophysiological basis for this correlation remains speculative.

We examined the distribution and abundance of hummingbirds at two study sites in southeastern Arizona, where we banded over 8000 individuals and 11 species in a 6-year period. We trapped approximately once a week from April to October at each site, from 1988–1992 at Sonoita, in oak woodlands, and 1991–1993 at Harshaw Creek, in a riparian area. Anna's (Calypte anna), Black-chinned (Archilochus alexandri), and Rufous (Selasphorus rufus) Hummingbirds were the most abundant species. At Harshaw Creek, Broad-billed (Cynanthus latirostris) and Costa's (Calypte costae) Hummingbirds occurred in significant numbers. A massive fall migration occurred at both sites, but few hummingbirds moved northward in spring. The large numbers of migrants were spaced over time within seasons, and the timing of peak migration for a species varied among years. Fall-migrant Black-chinned Hummingbirds peaked earliest with adult males preceding adult females and juveniles, followed by Rufous Hummingbirds (predominantly juveniles), then Anna's Hummingbirds. Of the most abundant species, Rufous Hummingbirds used the sites only during their migration, and the other four species bred at one or both sites. During the first three years of feeder use at Harshaw Creek, Anna's Hummingbirds significantly increased in numbers but other species did not. We also report how the age and sex classes for the common species varied in abundance between sites and among years. Distribución y Abundancia Estacional de Colibríes en Encinales y Comunidades Riparias en el Sureste de Arizona Resumen. Analizamos la distribución y abundancia de colibríes en dos sitios en el sureste de Arizona, donde se anillaron más de 8000 individuos de 11 especies durante un período de seis años. Durante los meses de abril a octubre entre 1988 y 1993, se capturaron colibríes una vez por semana, en un área de encinal abierto en Sonoita y por tres años en un área riparia en Harshaw Creek. Las especies más abundantes fueron: Calypte anna, Archilochus alexandri y Selasphorus rufus; en Harshaw Creek, Cynanthus latirostris y Calypte costae ocurrieron en cantidades significativas. En los dos sitios ocurrió una migración hacia el sur en forma masiva durante el otoño, pero muy pocos colibríes migraron hacia el norte durante la primavera. Los grandes números de migrantes estuvieron espaciados en el tiempo dentro de cada estación, y la fecha pico de migración para cada especie varió año a año. Durante la migración de otoño, el pico de migración más temprano fue el de A. alexandri, cuyos machos adultos migraron antes que las hembras adultas y los juveniles, seguido por el pico migratorio de S. rufus (dominado por juveniles) y después por el de C. anna. Una de las especies más abundantes (S. rufus) usa los sitios solamente durante su migración, mientras que las otras cuatro especies se reproducen en uno o ambos sitios. Durante los tres primeros años en que los colibríes utilizaron bebederos en Harshaw Creek, C. anna aumentó en forma significativa, pero las otras especies no. También reportamos cómo variaron las abundancias de las distintas clases de edad y sexo de un sitio a otro y entre los diferentes años para las especies más comunes.

✓ The incidence and character of neurological deficits following resection of glial neoplasms localized to the Heschl gyrus are currently unknown. In this series, the authors report the clinical presentation, management, and postoperative course of three patients with right hemisphere Heschl gyrus gliomas, one of whom developed difficulty with music production and comprehension postoperatively. Resection of right hemisphere Heschl gyrus gliomas can result in deficits involving music comprehension. Preliminary evidence suggests that when these deficits occur, they may be transient in nature.

OBJECTIVE: Resection of intracranial tumors in the posterior hippocampus and the parahippocampal gyrus can be associated with significant morbidity because of the parenchymal resection and the cortical retraction often required in gaining access to this infrequently explored region. With the use of image guidance, the occipitosubtemporal (OST) approach requires neither lateral cortical resection nor the placement of brain retractors to gain surgical access to the posterior hippocampus and the parahippocampal gyrus, and this approach is associated with a high rate of gross total tumor resection. METHODS: The computer-assisted volumetric stereotactic OST approach was used to resect 40 posterior hippocampus and parahippocampal gyrus tumors in 34 consecutive patients during an 8-year period. Patient, radiographic, and surgical outcome data were collected retrospectively. RESULTS: The series included operations in 25 men and 15 women, and the patients' average age was 40.3 years (range, 15–69 yr). Twenty-five of the 40 procedures were performed to remove lesions in the dominant hemisphere, and previous craniotomies for resection had been performed in 12 of 40 cases. In 38 of 40 cases, histopathological analysis revealed a glial neoplasm, and 50% of these tumors were high-grade lesions. Preoperatively, 23 patients were neurologically intact before 40 procedures, whereas visual field deficits were noted in 7 patients, mild hemiparesis was documented in 4 patients, and other neurological deficits were present in 9 patients. An excellent outcome (Glasgow Outcome Scale Grade 5) was noted after 38 (95%) of the 40 computer-assisted volumetric stereotactic OST procedures. Permanent postoperative hemiparesis (Glasgow Outcome Scale Grade 4) occurred after one procedure, and a second patient, despite being neurologically unchanged postoperatively and despite having had an optimal tumor resection, died on postoperative Day 33 (Glasgow Outcome Scale Grade 1). Complete resection of the preoperatively defined tumor volume was noted on postoperative gadolinium-enhanced magnetic resonance imaging examinations after 39 (97.5%) of the 40 procedures. The average duration of clinical follow-up was 15.9 months (range, 0.5–67 mo). CONCLUSION: We think that the OST approach is well suited to the resection of tumors in the posterior hippocampus and the parahippocampal gyrus. By allowing the neurosurgeon to avoid unnecessary brain resection and retraction, this approach reduces the risk of injury to important lateral temporal and occipital lobe cortex and tracts. In addition, the resection of a posterior hippocampus or parahippocampal gyrus mass with the OST approach relieves temporal horn entrapment. Computer-assisted volumetric stereotaxy helps the neurosurgeon to maintain precise spatial and anatomic orientation and accurately delineates the margin between the tumor and the surrounding neural tissue.

BACKGROUND Hearing loss after intracranial and spinal procedures involving cerebrospinal fluid loss is rarely reported in the literature. We report a patient who suffered from delayed hearing loss after cerebrospinal fluid shunting that improved after revising the shunt to a higher-pressure valve. CASE DESCRIPTION A 32-year-old woman presented with bilateral hearing loss 4 years after ventriculoperitoneal shunting for communicating hydrocephalus. Her otologic work-up revealed sensorineural hearing loss. In an attempt to improve her hearing, 6 years after the hearing loss began (10 years after the shunt was placed), she underwent a shunt revision in which her valve was changed to a higher-pressure device. After the procedure, she had a significant improvement in her speech discrimination and a mild improvement in her pure tone recognition. These changes were documented with serial audiograms. CONCLUSION Hearing loss after cerebrospinal shunting procedures is not always limited to the immediate postoperative period. It may be a late complication of cerebrospinal fluid diversion. Chronic hearing loss after ventriculoperitoneal shunting may be treatable by changing the valve to a higher-pressure device. The etiology of hearing loss from intracranial hypotension is briefly discussed.

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

The 2 aims of this study were as follows: 1) to establish outcome measures of nerve regeneration in an axolotl model of peripheral nerve injury; and 2) to define the timing and completeness of reinnervation in the axolotl following different types of sciatic nerve injury.The sciatic nerves in 36 axolotls were exposed bilaterally in 3 groups containing 12 animals each: Group 1, left side sham, right side crush; Group 2, left side sham, right side nerve resected and proximal stump buried; and Group 3 left side cut and sutured, right side cut and sutured with tibial and peroneal divisions reversed. Outcome measures included the following: 1) an axolotl sciatic functional index (ASFI) derived from video swim analysis; 2) motor latencies; and 3) MR imaging evaluation of nerve and muscle edema.For crush injuries, the ASFI returned to baseline by 2 weeks, as did MR imaging parameters and motor latencies. For buried nerves, the ASFI returned to 20% below baseline by 8 weeks, with motor evoked potentials present. On MR imaging, nerve edema peaked at 3 days postintervention and gradually normalized over 12 weeks, whereas muscle denervation was present until a gradual decrease was seen between 4 and 12 weeks. For cut nerves, the ASFI returned to 20% below baseline by Week 4, where it plateaued. Motor evoked potentials were observed at 2-4 weeks, but with an increased latency until Week 6, and MR imaging analysis revealed muscle denervation for 4 weeks.Multiple outcome measures in which an axolotl model of peripheral nerve injury is used have been established. Based on historical controls, recovery after nerve injury appears to occur earlier and is more complete than in rodents. Further investigation using this model as a successful "blueprint" for nerve regeneration in humans is warranted.

The objective of this chapter is to describe and discuss the radiographic, intraoperative, and histologic findings that are present after brachial plexus birth injury. This review is based on the authors’ clinical and operative experiences and a survey of the peer-reviewed literature. Together our findings provide evidence that in the vast majority of cases of brachial plexus birth palsy are secondary to a forceful traction injury affecting the brachial plexus that occurs when the child is born.

OBJECTIVE To describe a frameless stereotactic technique used to resect cerebral arteriovenous malformations (AVMs) and to determine whether frameless stereotaxy during AVM resection could decrease operative times, minimize intraoperative blood losses, reduce postoperative complications, and improve surgical outcomes. METHODS Data for 44 consecutive patients with surgically resected cerebral AVMs were retrospectively reviewed. The first 22 patients underwent resection without stereotaxy (Group 1), whereas the next 22 patients underwent resection with the assistance of a frameless stereotaxy system (Group 2). RESULTS The patient characteristics, AVM morphological features, and percentages of preoperatively embolized cases were statistically similar for the two treatment groups. The mean operative time for Group 1 was 497 minutes, compared with 290 minutes for Group 2 (P = 0.0005). The estimated blood loss for Group 1 was 657 ml, compared with 311 ml for Group 2 (P = 0.0008). Complication rates, residual AVM incidences, and clinical outcomes were similar for the two groups. CONCLUSION Frameless stereotaxy allows surgeons to 1) plan the optimal trajectory to an AVM, 2) minimize the skin incision and craniotomy sizes, and 3) confirm the AVM margins and identify deep vascular components during resection. These benefits of stereotaxy were most apparent for small, deep AVMs that were not visible on the surface of the brain. Frameless stereotaxy reduces the operative time and blood loss during AVM resection.

OBJECTIVE We report the incidence and clinical evolution of postoperative deficits and supplementary motor area (SMA) syndrome after volumetric stereotactic resection of glial neoplasms involving the posterior one-third of the superior frontal convolution. We investigated variables that may be associated with the occurrence of SMA syndrome. METHODS The postoperative clinical status of 27 consecutive patients who underwent resection of SMA gliomas was retrospectively reviewed. Neurological examination results were recorded 1 day, 1 week, 1 month, and 6 months postoperatively. The extent of tumor resection, the percentage of SMA resection, violation of the cingulate gyrus, and operative complications were tabulated. RESULTS The overall incidence of SMA-related deficits was 26% (7 of 27 patients), with 3 patients having complete SMA syndrome and 4 patients having partial SMA syndrome. Two additional patients (7.5%) had other postoperative deficits, including one with mild facial weakness and one with transient aphasia. The resection of low-grade gliomas was associated with a higher incidence of SMA syndrome, an outcome that likely reflects more complete removal of functional SMA cortex in this subset of patients. Intraoperative monitoring localized the precentral sulcus within the preoperatively defined tumor volume in 6 (22%) of 27 patients, thereby precluding gross total resection. All 27 patients had excellent outcomes at the 6-month follow-up examination. CONCLUSION When the resection of SMA gliomas is limited to the radiographic tumor boundaries, the incidence and severity of SMA syndrome may be minimized. With the use of these resection parameters, patients with high-grade SMA gliomas are unlikely to experience SMA syndrome. These findings are helpful in the preoperative counseling of patients who are to undergo cytoreductive resection of SMA gliomas.

Background The objective of this study was 2-fold: (1) document the presence and degree of vascularity in gliomas of different pathologic grades and (2) determine whether the presence of abnormal vascularity, determined by catheter angiography, correlates with a shortened survival. Methods As part of a protocol for radiographic data acquisition that was used in a computer-assisted, stereotactic system, all patients who underwent biopsy or resection of a newly diagnosed glioma between 1994 and 2000 at our institution routinely underwent preoperative catheter angiography. The presence and degree of tumor vascularity were recorded and then correlated with survival and pathologic grade. The confounding effects of age, KPS, adjuvant treatment, and extent of resection on survival were considered. Results Two hundred thirty-one patients were included in this study. The mean follow-up of survivors was 7.8 years. Tumor vascularity correlated with a shortened survival (proportional hazards RR for survival, 0.69; 95% CI, 0.58-0.82). This correlation persisted after correction for age, KPS score, adjuvant therapy, and extent of resection (RR, 0.81; 95% CI, 0.68-0.97). Abnormal vascularity was present in 25 (30%) of 82 low-grade (WHO grade 2) gliomas. Overall, the extent of vascularity (none [120 patients, 52%], blush [63 patients, 27%], neovessels [25 patients, 11%], and arteriovenous shunting [23 patients, 10%]) correlated with worse WHO tumor grade (P Conclusions The presence of abnormal vascularity correlates with both a shortened survival and higher grade of malignancy. These findings underscore the importance of antiangiogenesis factor investigation and drug development for the treatment of gliomas, regardless of their pathologic grade.

Using a fascicle-sparing approach, schwannomas and nonplexiform neurofibromas can often be removed without causing neurological deficit or neuropathic pain. This article provides a step-by-step description of how to remove these benign tumors using microsurgical techniques.

The objective of this study is to examine the utility of acetazolamide TCD ultrasound in the evaluation of MCA collateral blood flow reserve in patients with carotid occlusive disease.Acetazolamide TCD and cerebral angiography were performed for 28 carotid territories in 14 patients with carotid occlusive disease. The percentage change in mean blood flow velocity and PI in the MCA was measured before and after 1 g of acetazolamide was administered. The carotid territories were divided into groups according their angiographic findings: (1) mild/moderate (70%) vs severe (or =70%) extracranial carotid artery stenosis, and (2) active collateral blood flow to the MCA territory vs no collateral blood flow to the MCA.After acetazolamide injection, the percentage increase in mean MCA velocity for mild/moderate vs severe carotid artery stenosis was 43% +/- 10% and 19% +/- 6%, respectively, indicating less collateral blood flow reserve in patients with severe stenosis (P = .04). The percentage decrease in the PI for MCA territories with vs without angiographic evidence of collateral blood flow was 4.6% +/- 4% and 16% +/- 3%, respectively (P = .04), indicating an exhausted vascular reserve in patients with evidence of active collateral blood flow on angiography.A decrease in the PI after acetazolamide administration represents a safe and noninvasive indicator of limited collateral blood flow reserve to the MCA territory ipsilateral to an extracranial carotid stenosis. Further study into the role acetazolamide TCD has in the preoperative evaluation of these patients, including threshold values, is warranted.

Complication avoidance during peripheral nerve surgery has received little attention in the neurosurgical literature. The goal of our two-part review is to discuss these possible complications, with this initial article highlighting the pitfalls associated with pre- and intraoperative assessment of nerve injuries, as well as the operative nuances used during brachial plexus exploration to minimize complications.