ARISE I Consensus Review on the Management of Intracranial Aneurysms.

BACKGROUND: Intracranial aneurysms (IAs) remain a challenging neurological diagnosis associated with significant morbidity and mortality. There is a plethora of microsurgical and endovascular techniques for the treatment of both ruptured and unruptured aneurysms. There is no definitive consensus as to the best treatment option for this cerebrovascular pathology. The Aneurysm, Arteriovenous Malformation, and Chronic Subdural Hematoma Roundtable Discussion With Industry and Stroke Experts discussed best practices and the most promising approaches to improve the management of brain aneurysms. METHODS: A group of experts from academia, industry, and federal regulators convened to discuss updated clinical trials, scientific research on preclinical system models, management options, screening and monitoring, and promising novel device technologies, aiming to improve the outcomes of patients with IA. RESULTS: Aneurysm, Arteriovenous Malformation, and Chronic Subdural Hematoma Roundtable Discussion With Industry and Stroke Experts suggested the incorporation of artificial intelligence to capture sequential aneurysm growth, identify predictors of rupture, and predict the risk of rupture to guide treatment options. The consensus strongly recommended nationwide systemic data collection of unruptured IA radiographic images for the analysis and development of machine learning algorithms for rupture risk. The consensus supported centers of excellence for preclinical multicenter trials in areas such as genetics, cellular composition, and radiogenomics. Optical coherence tomography and magnetic resonance imaging contrast-enhanced 3T vessel wall imaging are promising technologies; however, more data are needed to define their role in IA management. Ruptured aneurysms are best managed at large volume centers, which should include comprehensive patient management with expertise in microsurgery, endovascular surgery, neurology, and neurocritical care. CONCLUSIONS: Clinical and preclinical studies and scientific research on IA should engage high-volume centers and be conducted in multicenter collaborative efforts. The future of IA diagnosis and monitoring could be enhanced by the incorporation of artificial intelligence and national radiographic and biologic registries. A collaborative effort between academic centers, government regulators, and the device industry is paramount for the adequate management of IA and the advancement of the field.

Risk Factors for Headache Disorder in Patients With Unruptured Intracranial Aneurysms.

OBJECTIVE: Headache disorders are a prevalent yet frequently underestimated issue in patients with unruptured intracranial aneurysms (UIAs). The primary aim of this study is to systematically examine the incidence, specific characteristics, and associated risk factors of headache disorders in the context of individuals diagnosed with UIAs. Through this investigation, we hope to contribute valuable insights to the current understanding of this complex relationship and potentially inform future diagnostic and treatment approaches. METHODS: Data from 146 consecutive patients harboring UIAs were evaluated. The location and morphological characteristics of the aneurysm were analyzed. Factors associated with headache incidence and methods of treatment were investigated. The headache pattern in 48 patients was assessed using self-reported questionnaires. RESULTS: A total of 146 patients were identified. Out of 146 patients, 95 (65%) were in the Headache Group (HG) and 51 (35%) were asymptomatic and in the No Headache Group (NHG). Factors associated with a higher likelihood of headache were past or current tobacco, alcohol, and illicit drug use (p=0.029). On average, patients had 1.49 (SD=1) aneurysms in the HG and 1.43 (SD=.92) in the NHG group, respectively. In our series, the size of aneurysms, the status of the aneurysm (treated vs untreated), and the method of treatment did not significantly differ between the groups. There was a high incidence of headaches in patients with aneurysms of the ophthalmic segment (C6) of the internal carotid artery (ICA) and sphenoidal segment (M1) of the middle cerebral artery (MCA). Of 48 patients that completed headache questionnaires, 25 had headaches on more than 15 days a month. The majority of participants (85.4%) reported the severity of their pain as being greater than 5 on a scale of 10, while one-third (33.3%) experienced the maximum pain level of 10 out of 10. CONCLUSION: Headache more often occurs in patients with aneurysms of the ophthalmic segment (C6) of the ICA and sphenoidal segment (M1) of the MCA. Its distinctive features are deep pain for more than 15 days a month. Although the treatment of aneurysms reduces the risk of aneurysmal rupture, its efficacy in relieving the headache is still uncertain.

Racial Disparities in Perioperative Morbidity Following Oncological Spine Surgery.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To assess the impact of race on complications following spinal tumor surgery. METHODS: Adults with cancer who underwent spine tumor surgery were identified in the American College of Surgeons National Surgical Quality Improvement Program datasets from 2012 to 2016. Clavien-Dindo Grade I-II (minor complications) and Clavien-Dindo Grade III-V (major complications including 30-day mortality) complications were compared between non-Hispanic Whites (NHW) and Black patients. A multivariable analysis was also conducted. RESULTS: Of 1,226 identified patients, 85.9% were NHW (n = 1,053) and 14.1% were Black (n = 173). The overall rate of Grade I-II complications was 16.2%; 15.1% for NHW patients and 23.1% for Black patients (P = .008). On multivariable analysis, Black patients had significantly higher odds of having a minor complication (OR 1.87; 95% CI, 1.16-3.01; P = .010). On the other hand, the overall rate of Grade III-V complications was 13.3%; 12.5% for NHW patients and 16.2% for Black patients (P = .187). On multivariable analysis, Black race was not independently associated with major complications (OR 1.26; 95% CI, 0.71-2.23; P = .430). Median length of stay was 8 days (IQR 5-13) for NHW patients and 10 days (IQR 6-15) for Black patients (P = .011). CONCLUSION: Black patients who underwent metastatic spinal tumor surgery were at a significantly increased risk of perioperative morbidity compared to NHW patients independent of baseline and operative characteristics. Major complications did not differ between groups. Race should be further studied in the context of metastatic spine disease to improve our understanding of these disparities.

Deadliness of Traumatic Subdural Hematomas in the First Quarter of the Year: A Measurement by the American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP).

Background Traumatic acute subdural hematoma (ASDH) is a surgical emergency and has been associated with high morbidity and mortality. However, it is not known whether mortality from ASDH occurs more frequently in a particular season. Methodology We queried the American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP) from 2016 to 2019. They were identified in the NSQIP using the International Classification of Diseases (ICD-10) code S06.5 to capture all admissions with a primary diagnosis of traumatic subdural hematoma. Mortality rates were reviewed per season, defined as three consecutive months in the year. Demographics such as age, race, ethnicity, height, and weight were reviewed. Comorbidities such as diabetes, risk factors, including smoking history, and hospitalization characteristics, such as admission year, operation year, and inpatient/outpatient treatment type, were also reviewed. Results A total of 1,656 patients were included in this study. The mean age of all participants was 70.6 years, with 37% (604/1,656) being female. The mortality rate was highest in January, February, and March at 24.5% (104/425, P = 0.045) of admitted patients compared to mortality rates of 18.8% (70/373) in April to June, 18.4% (81/441) in July to September, and 17.5% (73/417) in October to December. Conclusions Mortality is significantly greater during the winter months of January, February, and March among patients with ASDH. Despite better survival rates of ASDH over the past two decades, postoperative mortality rates still remain high.

A case of hydrocephalus confounded by suprasellar arachnoid cyst and concomitant reversible cerebral vasoconstriction syndrome.

Background: Obstructive hydrocephalus is a neurologic condition that has varied clinical and imaging presentations, as well as a multitude of congenital etiologies including aqueductal stenosis and less commonly arachnoid cysts. Aqueductal stenosis is a physical limitation to cerebrospinal fluid flow along the course of the aqueduct, which results in enlargement of the third and lateral ventricles. Arachnoid cysts are thin walled and fluid filled central nervous system lesions that can result in mass effect on adjacent structures. While arachnoid cysts are mostly asymptomatic, they may present with neurological symptoms that vary depending on the location of the lesion. Suprasellar cysts in particular may cause obstructive hydrocephalus as well as endocrine dysfunction. Reversible cerebral vasoconstriction syndrome (RCVS) is an unusual condition caused by cerebral arterial vasoconstriction that often presents initially with a thunderclap headache. Frequently, there is some environmental trigger associated with this condition. RCVS more commonly affects women and can induce stroke. Case Description: A 57-year-old female presented to the emergency department with progressive headache and visual changes. Initial workup suggested the patient's symptoms where related to RCVS but subsequent surgical management of what was presumed to be long standing, compensated hydrocephalus resulted in resolution of the patient's symptoms. Conclusion: We report, to the best of our knowledge, the first case of aquedutal stenosis and suprasellar arachnoid cyst with concomitant RCVS. The presence of multiple pathologies found on radiologic imaging illustrates the challenges presented by incidental findings and subsequent anchoring bias in medical diagnosis.

Pipeline Embolization Device and Pipeline Flex Versus Surpass Streamline Flow Diversion in Intracranial Aneurysms: A Retrospective Propensity Score-Matched Study.

OBJECTIVE: To compare safety and efficacy profiles in aneurysms treated with Pipeline Embolization Device or Pipeline Flex versus Surpass Streamline flow diverters (FDs). METHODS: Patients who underwent flow diversion for aneurysm treatment at 2 centers were included. Covariates comprised patient demographics, comorbidities, and aneurysm characteristics. Metrics included number of devices, adjuvant device use, case duration, and radiation exposure. Outcomes included periprocedural complications and radiographic results at follow-up. Propensity score-matched pairs were generated using demographic and aneurysm characteristics to verify the outcomes in equally sized groups. RESULTS: The majority of 141 flow diversion procedures performed on 126 patients were in the anterior circulation (96%) and unruptured (93%). Operators experienced more complications placing Surpass FDs compared with Pipelines (18.2% vs. 3.1%, P = 0.005) but used fewer Surpass devices per case (1 device in all Surpass cases and range for Pipeline cases 1-7; P < 0.001). Ballooning was more frequent for Surpass (29.5% vs. 2.1%, P < 0.001). There were no differences in mortality (2.1% vs. 0, P = 1.00), intracranial hemorrhage (3.1% vs. 0, P = 0.551), or stroke (4.2% vs. 6.8%, P = 0.680). Rates of aneurysm obliteration at follow-up were similar. Propensity-matched pairs had no differences in FD deployment complications or perioperative events, yet the significant differences remained for adjuvant balloon use and number of FDs deployed. CONCLUSIONS: While the devices demonstrated similar safety and efficacy profiles, deployment of the Surpass Streamline was more technically challenging than Pipeline Embolization Device or Pipeline Flex. Prospective cohort studies are needed to corroborate these findings.

Classical Risk Factors for Ischemic Stroke are not Associated with Inpatient Post-Stroke Mortality in Sickle Cell Disease.

OBJECTIVES: Sickle cell disease is a common haemoglobinopathy that significantly increases the risk of ischemic stroke. Because the risk factors for ischemic stroke onset and mortality in non-sickle cell disease patients have been largely elucidated, this paper aims to analyze risk factors for ischemic stroke mortality in sickle cell disease patients, which remain largely unknown. MATERIALS/METHODS: The National Inpatient Sample database (2016-2017) was used to develop a multivariable regression model for risk quantification of known ischemic stroke risk factors for in-hospital mortality in ischemic stroke patients with and without sickle cell disease. RESULTS: Classical risk factors for ischemic stroke onset, including ischemic heart disease, carotid artery disease, lipidemias, hypertension, obesity, tobacco use, atrial fibrillation, personal or family history of stroke, congenital heart defects, congestive heart failure, cardiac valve disorder, peripheral vascular disease, and diabetes mellitus are associated with in-hospital mortality in non-sickle cell patients (p < 0.05). However, no significant association was found between these stroke risk factors and in-hospital mortality in sickle cell disease patients presenting with ischemic stroke (p > 0.05). CONCLUSIONS: While the classical risk factors for stroke onset are associated with in-hospital mortality in non-sickle cell stroke patients, they are not associated with in-hospital mortality in sickle cell stroke patients.

Re-Evaluating Stroke Systems of Care: Association of Transfer Status With Thrombectomy Outcomes at an Urban Comprehensive Stroke Center.

Introduction Given the efficacy of mechanical thrombectomies (MT) for large vessel occlusions (LVO), there is concern that the Hub and Spoke model of stroke care, which prioritizes initial assessment of the acute ischemic stroke (AIS) patient at a primary stroke center, would cause a delay in arterial reperfusion, thus leading to worse outcomes. In this study that occurred at our comprehensive stroke center in New York, we compared the clinical outcomes of patients that were either directly admitted for thrombectomy versus those who were transferred from another institution. Methods Retrospective review of the electronic medical record (EMR) was performed on all adult patients treated with endovascular therapy for ischemic stroke between January 2016 and February 2020. A bivariate analysis was performed to compare patients in the direct admit versus transfer group. A multivariable logistic regression model was developed to determine which factors affect 90-day modified Rankin score (mRS) and to evaluate if transfer status was an independent predictor in this model. Results Three hundred and twenty-five patients were included in this study; 127 patients belonged to the direct admit group while 198 were in the transfer group. Thirteen patients (20%) in the direct admit group had a 90-day mRS score of 0-2 and so did 29 patients (25.2%) in the transfer group; thus, no statistically significant difference found in clinical outcomes between both groups (p-value = 0.427). In a multivariable logistic regression model that accounts for age, gender, smoking status, baseline mRS, presenting National Institute of Health Stroke Scale (NIHSS), procedure duration, thrombolysis in cerebral infarction (TICI) score, post-NIHSS and decompressive hemicraniectomy, transfer status was not found to be predictive of clinical outcomes (OR 0.727 95% CI 0.349-1.516; p-value = 0.396).  Conclusion Transfer status is not significantly associated with 90-day outcome. Since Hub and Spoke is not associated with worse outcomes compared to direct admit, it remains a viable model for providing effective care to stroke patients in an urban setting.

Moyamoya Disease and Syndrome: A National Inpatient Study of Ischemic Stroke Predictors.

OBJECTIVES: Ischemic stroke and hemorrhagic stroke are the most common sequelae of the Moyamoya variants [Moyamoya disease (MMD) and syndrome (MMS)]. We sought to determine the rates of stroke subtypes and the predictive factors of arterial ischemic stroke (AIS) utilizing a large data sample of MMD and MMS patients in the US. MATERIALS AND METHODS: We queried the 2016 and 2017 National Inpatient Sample database for Moyamoya diagnosis plus any of the following associated conditions; sickle cell disease, neurofibromatosis type 1, cranial radiation therapy or Down Syndrome. Multivariate regression determined the risk factors for AIS onset in MMD and MMS. RESULTS: 2323 patients with a diagnosis of Moyamoya were included; 668 (28.8%) patients were classified as MMS and 1655 (71.2%) as MMD. AIS was the most common presentation in both cohorts; however, MMD patients had higher rates of AIS (20.4 vs 6%, p < 0.001), hemorrhagic stroke (7.4vs 2.5%, p < 0.001), and TIA (3.3vs 0.9%, p = 0.001) compared to MMS patients. Multivariate analysis showed that increasing age [OR = 1.017 95%CI: 1.008-1.03, p < 0.001], lipidemia [OR = 1.32 95%CI: 1.02-1.74, p = 0.049], and current smoking status [OR = 1.43 95%CI: 1.04-1.97, p = 0.026] were independent risk factors for AIS in MMD patients, whereas hypertension [OR = 2.61 95%CI: 1.29-5.25, p = 0.007] and African-American race [OR = 0.274, 95%CI: .117-.64, p = 0.003] were independent predictors in the MMS cohort. CONCLUSION: AIS is the most common presentation in both, MMD and MMS. However, MMD patients had higher rates of stroke events compared to MMS. Risk factors for AIS in MMD included increasing age, lipidemia and smoking status, whereas in MMS hypertension was the only independent risk factor.

Surgical or Endovascular Management of Middle Cerebral Artery Aneurysms: A Randomized Comparison.

OBJECTIVE: There are few randomized data comparing clipping and coiling for middle cerebral artery (MCA) aneurysms. We analyzed results from patients with MCA aneurysms enrolled in the CURES (Collaborative UnRuptured Endovascular vs. Surgery) and ISAT-2 (International Subarachnoid Aneurysm Trial II) randomized trials. METHODS: Both trials are investigator-led parallel-group 1:1 randomized studies. CURES includes patients with 3-mm to 25-mm unruptured intracranial aneurysms (UIAs), and ISAT-2 includes patients with ruptured aneurysms (RA) for whom uncertainty remains after ISAT. The primary outcome measure of CURES is treatment failure: 1) failure to treat the aneurysm, 2) intracranial hemorrhage during follow-up, or 3) residual aneurysm at 1 year. The primary outcome of ISAT-2 is death or dependency (modified Rankin Scale score >2) at 1 year. One-year angiographic outcomes are systematically recorded. RESULTS: There were 100 unruptured and 71 ruptured MCA aneurysms. In CURES, 90 patients with UIA have been treated and 10 await treatment. Surgical and endovascular management of unruptured MCA aneurysms led to treatment failure in 3/42 (7%; 95% confidence interval [CI], 0.02-0.19) for clipping and 13/48 (27%; 95% CI, 0.17-0.41) for coiling (P = 0.025). All 71 patients with RA have been treated. In ISAT-2, patients with ruptured MCA aneurysms managed surgically had died or were dependent (modified Rankin Scale score >2) in 7/38 (18%; 95% CI, 0.09-0.33) cases, and 8/33 (24%; 95% CI, 0.13-0.41) for endovascular. One-year imaging results were available in 80 patients with UIA and 62 with RA. Complete aneurysm occlusion was found in 30/40 (75%; 95% CI, 0.60-0.86) patients with UIA allocated clipping, and 14/40 (35%; 95% CI, 0.22-0.50) patients with UIA allocated coiling. Complete aneurysm occlusion was found in 24/34 (71%; 95% CI, 0.54-0.83) patients with RA allocated clipping, and 15/28 (54%; 95% CI, 0.36-0.70) patients with RA allocated coiling. CONCLUSIONS: Randomized data from 2 trials show that better efficacy may be obtained with surgical management of patients with MCA aneurysms.

The incidence of venous thromboembolism following surgical resection of intracranial and intraspinal meningioma. A systematic review and retrospective study.

INTRODUCTION: Historically, the development of venous thromboembolism (VTE) including deep venous thrombosis (DVT) and pulmonary thromboembolism (PE) was cited as a higher post-operative risk for patients harboring meningiomas. However, recent literature has suggested that there may be no elevated risk for VTE among these patients. The authors perform both a retrospective review of their own cases as well as a systematic review of the literature in order to determine the frequency of the VTE and rate of post-operative hemorrhage in this patient population. METHODOLOGY: Patients undergoing surgery for intracranial and spinal meningioma from 2012 to 2019 were retrospectively reviewed for patient demographics, clinical characteristics, and post-operative complications. Logistic regression was used to determine risk factors for the development of VTE. Additionally, a PubMed search was performed to identify patients addressing this topic. RESULTS: Our retrospective review included 189 patients who underwent 197 operations. The rate of VTE for patients receiving LMWH was 3.55 % vs. 4.06 % for those not receiving LMWH. There were no observed hemorrhages after initiation of LMWH. Multivariate analysis found tumor volume, history of DVT, and length of hospital stay as independent risk factors for VTE. In the systematic review, 11 papers describing 28,954 patients were included. The risk of developing a VTE with or without LMWH was 2.71 % versus 4.07 %, respectively. The hemorrhage risk was 2.23 % on LMWH versus 4.20 % not on LMWH. DISCUSSION: In several heterogeneous series of all types of neurosurgical procedures, the reported rate of VTE was 11.1 %. In our review of the literature, the VTE rate of 2.71 % was similar to our cohort's rate of 3.55 %, for patients administered LMWH postoperatively. Higher rates of VTE with meningiomas may not be the case as once thought. Regular use of LMWH appears to be a safe, but it also did not necessarily lower the rates of VTE in our cohort. The use of routine lower-extremity duplex ultrasound, mechanical prophylaxis, and early mobilization, may have contributed to these lower rates of VTEs in patients with meningiomas.

Predictors of mortality for patients with COVID-19 and large vessel occlusion.

BACKGROUND: This study evaluates the mortality risk of patients with emergent large vessel occlusion (ELVO) and COVID-19 during the pandemic. METHODS: We performed a retrospective cohort study of two cohorts of consecutive patients with ELVO admitted to a quaternary hospital from March 1 to April 17, 2020. We abstracted data from electronic health records on baseline, biomarker profiles, key time points, quality measures and radiographic data. RESULTS: Of 179 patients admitted with ischemic stroke, 36 had ELVO. Patients with COVID-19 and ELVO had a higher risk of mortality during the pandemic versus patients without COVID-19 (OR 16.63, p = 0.004). An age-based sub-analysis showed in-hospital mortality in 60% of COVID-19 positive patients between 61-70 years-old, 66.7% in between 51-60 years-old, 50% in between 41-50 years-old and 33.3% in between 31-40 years old. Patients that presented with pulmonary symptoms at time of stroke presentation had 71.4% mortality rate. 27.3% of COVID-19 patients presenting with ELVO had a good outcome at discharge (mRS 0-2). Patients with a history of cigarette smoking (p = 0.003), elevated d-dimer (p = 0.007), failure to recanalize (p = 0.007), and elevated ferritin levels (p = 0.006) had an increased risk of mortality. CONCLUSION: Patients with COVID-19 and ELVO had a significantly higher risk for mortality compared to COVID-19 negative patients with ELVO. A small percentage of COVID-19 ELVO patients had good outcomes. Age greater than 60 and pulmonary symptoms at presentation have higher risk for mortality. Other risk factors for mortality were a history of cigarette smoking, elevated, failure to recanalize, elevated d-dimer and ferritin levels.

Jaw Elevation Device: Tool for Neck Immobilization to Facilitate Recovery in Endovascular Thrombectomy via Transcervical Access.

BACKGROUND: Acute stroke resolution via endovascular thrombectomy requires transcarotid access when transfemoral access is not possible. Although postoperative complications such as cervical hematoma and airway compression have been reported, an appropriate postprocedural management is largely unknown yet. We aim to provide new insights and learning points from our experience using the Jaw Elevation Device (JED) as a tool to facilitate recovery post surgery. CASE DESCRIPTION: A 79-year-old female underwent endovascular thrombectomy via transcervical, transcarotid access for a left internal carotid artery occlusion. No intraprocedural complications were reported. After successful thrombectomy, manual compression was applied in the carotid artery, and to achieve neck immobilization a JED was used for 4 hours after the procedure. No complications occurred. CONCLUSIONS: JED appears to be a reasonable option to facilitate patient recovery due to its capacity to maintain the airway, provide mild compression for hemostasis, and prevent cervical hematoma through a comfortable neck immobilization.

Use of Bone Morphogenetic Protein-2 in Vertebral Column Tumor Surgery: A National Investigation.

OBJECTIVE: To report the rate of bone morphogenetic protein-2 (BMP-2) use in vertebral column tumor surgery. METHODS: The Nationwide Inpatient Sample database (2012-2014) was queried to identify patients who underwent spinal fusion for vertebral column tumors (primary benign, primary malignant, or metastatic). The rate of BMP-2 use was calculated, and patient and operative factors associated with its use were also investigated. RESULTS: We identified 9375 patients who underwent fusion surgery for spinal tumors between 2012 and 2014, with 540 cases using BMP-2 (5.8%). Preoperative diagnosis revealed that the rate of BMP-2 use in primary benign tumor surgery was 4.9%, 7.6% for primary malignant tumors, and 5.7% for metastatic lesions (P = 0.607). The overall complication rate was 13.2% (13.4% in the NO-BMP-2 group vs. 11.1% in the BMP-2 group; P = 0.504). Patients who received this growth factor were less likely to have epidural spinal cord compression at presentation (37.0% vs. 49.2%; P = 0.014), and more likely to have elective surgery (53.7% vs. 37.7%; P < 0.001). Analysis of hospital location indicated that the highest use of BMP-2 was in the South (7.4% rate; P = 0.002). There was no statistical difference between age, sex, insurance status, comorbidities, the presence of a pathologic fracture, or the use of inpatient radiotherapy or chemotherapy between patients who received BMP-2 and controls. CONCLUSIONS: BMP-2 has been used off-label to promote arthrodesis; however, its use in patients with spinal tumors is controversial. In this national study, BMP-2 use was highest in the South, in patients without epidural cord compression at presentation, and in elective cases.

Hemorrhagic intracranial follicular dendritic cell sarcoma: A case report.

BACKGROUND: Follicular dendritic cell (FDC) sarcoma is an extremely rare neoplasm, which has only been reported once in the literature with an intracranial occurrence. Neither hemorrhagic presentation of an intracranial instance of FDC sarcoma nor its rapid recurrence has yet been published in the literature. CASE DESCRIPTION: We report the case of a 61-year-old female who presented with confusion and headaches secondary to a right frontal hemorrhagic lesion, and her subsequent presentations for recurrence of the lesion and finding of a new intracranial lesion. Immunohistopathologic analysis confirmed the diagnosis based on immunoreactivity for clusterin and CD 35. CONCLUSION: As demonstrated in this case report, the presentation and progression of primary intracranial follicular dendritic cell sarcoma can often be misleading, and consideration for this rare entity should be made in cases of hemorrhagic dural-based lesions without a primary source of malignancy.

Somatosensory evoked potential monitoring detection of carotid compression during ACDF surgery in a patient with a vascularly isolated hemisphere.

The authors report herein a case of anterior cervical discectomy and fusion (ACDF) surgery in which findings on somatosensory evoked potential (SSEP) monitoring led to the correction of carotid artery compression in a patient with a vascularly isolated hemisphere (no significant collateral blood vessels to the carotid artery territory). The amplitude of the cortical SSEP component to left ulnar nerve stimulation progressively decreased in multiple runs, but there were no changes in the cervicomedullary SSEP component to the same stimulus. When the lateral (right-sided) retractor was removed, the cortical SSEP component returned to baseline. The retraction was then intermittently relaxed during the rest of the operation, and the patient suffered no neurological morbidity. Magnetic resonance angiography demonstrated a vascularly isolated right hemisphere. During anterior cervical spine surgery, carotid artery compression by the retractor can cause hemispheric ischemia and infarction in patients with inadequate collateral circulation. The primary purpose of SSEP monitoring during ACDF surgery is to detect compromise of the dorsal column somatosensory pathways within the cervical spinal cord, but intraoperative SSEP monitoring can also detect hemispheric ischemia. Concurrent recording of cervicomedullary SSEPs can help differentiate cortical SSEP changes due to hemispheric ischemia from those due to compromise of the dorsal column pathways. If there are adverse changes in the cortical SSEPs but no changes in the cervicomedullary SSEPs, the possibility of hemispheric ischemia due to carotid artery compression by the retractor should be considered.

Computed tomography-guided lumbar drain placement.

The authors describe a technique for lumbar drain placement using CT guidance. Midline or paramidline interlaminar approaches to the thecal sac can be used. The major advantage to CT guidance is direct visualization of the needle tip in relation to the thecal sac. This technical approach is a safe and rapid alternative to fluoroscopic guidance for the placement of lumbar drains in patients in whom standard lumbar drain placement techniques have failed.