Prophylactic cerebrospinal fluid drainage and spinal cord ischemia in thoracic and thoracoabdominal endovascular procedures: a systematic review and meta-analysis.

Background: Spinal cord ischemia (SCI) is one of the most devastating complications of thoracic endovascular aortic repair (TEVAR). Prophylactic cerebrospinal fluid drainage (CSFD) has been shown to decrease the risk of SCI in open thoracic aortic procedures; however, its utility in TEVAR remains uncertain. This systematic review and meta-analysis aim to determine the role of prophylactic CSFD in preventing SCI in TEVAR. Methods: A literature search of five databases was performed and all studies published before September 2022 that reported SCI rates in TEVAR patients undergoing prophylactic CSFD were included. A random effects meta-analysis of means or proportions was performed for single-arm data. Odds ratios (ORs) with 95% confidence intervals (CIs) were reported for comparisons between groups. Results: A total of 4,793 patients undergoing TEVAR from 40 studies were included. The mean age was 68.8 years and 70.9% of patients were male. The overall SCI rate was 3.5%, with a 1.3% rate of immediate SCI and a 1.9% rate of delayed SCI. There were no significant differences in SCI rates between prophylactic CSFD patients and non-drained patients. Routine CSFD did not have a significant impact on SCI rates compared to non-drained patients. There was an increased rate of transient SCI with selective CSFD compared to non-drained patients (OR 2.08; 95% CI: 1.06-4.08; P=0.03). The most common drain-related complication was spinal headache (4.3%). The major complication rate was 1.6%, of which epidural or spinal hematoma (0.9%) was the most common, followed by intracranial or subdural hemorrhage (0.8%) and paraparesis or paraplegia (0.8%). Conclusions: This study found no significant difference in SCI rates between prophylactic CSFD patients and their non-drained counterparts. CSFD is associated with a small but non-negligible risk of serious complications. Multi-center randomized controlled trials (RCTs) are warranted to help stratify the risk of both SCI and CSFD-related complications in patients undergoing endovascular aortic procedures.

Procedural and clinical outcomes of transcatheter aortic valve replacement in bicuspid aortic valve patients: a systematic review and meta-analysis.

Background: Currently, bicuspid aortic valve (BAV) anatomy remains a relative contraindication for transcatheter aortic valve replacement (TAVR) due to concerns of suboptimal anatomy. However, recent advancements in the field have provided a wealth of promising data and more clinicians are opting for TAVR as an alternative to surgical repair. We aim to review and analyze the available data for TAVR in BAV patients, targeting procedural outcomes, clinical outcomes and mortality with up to two years of follow-up. Methods: A literature search of five databases was performed and all primary studies published between 2002 and 2021 that reported procedural, clinical or mortality outcome data were identified. Following data extraction, a meta-analysis of means or proportions was performed using a random effects model. Heterogeneity was assessed using the I2 statistic. Results: A total of 22 studies with 1,945 BAV patients were identified. The mean age was 74.1 years and 58.8% of patients were male. Device success rates was 87.5%. Moderate to severe paravalvular leak (PVL) was seen in 3.7% of procedures. Clinical outcomes included new permanent pacemaker insertion (PPI) (11.8%), major bleeding (3.5%), major vascular complications (2.5%), stroke (2.3%), acute kidney injury (2.1%) and coronary obstruction (0.1%). Mortality in hospital, at 30-days, one and two years of follow-up were 1.9%, 2.1%, 9.6% and 12.9%, respectively. Conclusions: This assessment of the available data on TAVR for BAV shows promising outcomes and low rates of complications. However, further research is warranted to reduce the heterogeneity of the available data and provide insight into outcomes beyond two years of follow-up.

Endovascular repair of acute complicated type B aortic dissection-systematic review and meta-analysis of long-term survival and reintervention.

BACKGROUND: Thoracic endovascular repair (TEVAR) is considered the first-line therapy in the repair of acute complicated type B aortic dissection (AC-BAD). Given the difficulty of designing randomized trials in this surgical cohort, long-term outcome data is limited. This systematic review and meta-analysis provide a complete aggregation of reported long-term survival and freedom from reintervention of AC-BAD patients based on the existing literature. METHODS: Three databases were searched from date of database inception to January 2021. The relevant references were identified and baseline cohort characteristics, survival and freedom from reintervention were extracted. The primary endpoints were survival and freedom from reintervention, whilst secondary endpoints were post-operative outcomes such as cord ischemia and endoleak. Kaplan-Meier curves were digitized and aggregated as per established procedure. RESULTS: A total of 2,812 references were identified in the literature search for review, with 46 selected for inclusion. A total of 2,565 patients were identified, of which 1,920 (75%) were male. The mean age of the cohort was 59.8±5.8. Actuarial survival at 2, 4, 6 and 10 years was 87.5%, 83.2%, 78.5% and 69.7%, respectively. Freedom from all secondary reintervention at 2, 4, 6, 8 and 10 years was 74.7%, 69.1%, 65.7%, 63.9% and 60.9%, respectively. When accounting for study quality, actuarial survival at 2, 4, 6 and 8 years was 85.4%, 79.1%, 69.8% and 63.1%, respectively. Freedom from all secondary reintervention at 2, 4, 6 and 8 years was 73.2%, 67.6%, 63.7% (maintained), respectively. CONCLUSIONS: TEVAR is associated with promising long-term survival extended to 10 years, though rates of freedom from reintervention remain an ongoing point for improvement. Randomized controlled trials comparing endovascular with open repair in the setting of acute, complicated type B aortic dissection are needed.

Analysis of academic publishing output among 1634 successful applicants in the 2011-2018 neurosurgery residency match.

BACKGROUND: Research productivity is a key criterion for applicant selection reported by residency program directors. Research volume reported on neurosurgery residency applications has risen steadily over the past decade. OBJECTIVE: Perform retrospective bibliographic searches of successful applicants who matched into U.S. neurosurgery residency programs from 2011 to 2018, and assess the relationship between academic publishing and residency placement. METHODS: Gender, MD/PhD status, U.S. News research ranking of medical school, and international medical graduate status (IMG) were determined for 1634 successful applicants from 2011 to 2018. Indexed publications before and after the start of residency were tabulated by Scopus®. Publication counts were stratified by first author, basic/clinical science, case reports, reviews, or other research. We then compared publishing trends across demographic variables and match cohorts. RESULTS: Average pre-residency publications increased from 2.6 [1.7, 3.4] in 2011 to 6.5 [5.1, 7.9] in 2018. Men, PhD-holders, Top 20 and Top 40 U.S. medical school graduates, and IMGs had higher pre-residency publication counts overall. After stratifying by match cohort, however, there was no significant effect of gender on pre-residency publications. Applicants matching into residency programs with highly ranked affiliated hospitals had significantly higher pre-residency publications. CONCLUSION: Publishing volume of successful neurosurgery applicants in the U.S. has risen recently and is associated with the stature of matched residency programs. Given the gap between verifiable and claimed research on residency applications, attention is needed to objectively evaluate research credentials in the selection process. The impending phase out of USMLE step 1 scores may increase emphasis on academic productivity.

Intratumor injection of CCL21-coupled vault nanoparticles is associated with reduction in tumor volume in an in vivo model of glioma.

PURPOSE: Glioblastoma (GBM) is the most common and malignant primary adult brain tumor. Current care includes surgical resection, radiation, and chemotherapy. Recent clinical trials for GBM have demonstrated extended survival using interventions such as tumor vaccines or tumor-treating fields. However, prognosis generally remains poor, with expected survival of 20 months after randomization. Chemokine-based immunotherapy utilizing CCL21 locally recruits lymphocytes and dendritic cells to enhance host antitumor response. Here, we report a preliminary study utilizing CPZ-vault nanoparticles as a vehicle to package, protect, and steadily deliver therapy to optimize CCL21 therapy in a murine flank model of GBM. METHODS: GL261 cells were subcutaneously injected into the left flank of eight-week-old female C57BL/6 mice. Mice were treated with intratumoral injections of either: (1) CCL21-packaged vault nanoparticles (CPZ-CCL21), (2) free recombinant CCL21 chemokine empty vault nanoparticles, (3) empty vault nanoparticles, or 4) PBS. RESULTS: The results of this study showed that CCL21-packaged vault nanoparticle injections can decrease the tumor volume in vivo. Additionally, this study showed mice injected with CCL21-packaged vault nanoparticle had the smallest average tumor volume and remained the only treatment group with a negative percent change in tumor volume. CONCLUSIONS: This preliminary study establishes vault nanoparticles as a feasible vehicle to increase drug delivery and immune response in a flank murine model of GBM. Future animal studies involving an intracranial orthotopic tumor model are required to fully evaluate the potential for CCL21-packaged vault nanoparticles as a strategy to bypass the blood brain barrier, enhance intracranial immune activity, and improve intracranial tumor control and survival.

Timing of adjuvant radiation therapy and survival outcomes after surgical resection of intracranial non-small cell lung cancer metastases.

OBJECTIVE: To investigate if delay of adjuvant radiotherapy (ART) beyond 6 post-operative weeks affects survival outcomes in patients undergoing craniotomy or craniectomy for resection of non-small cell lung cancer (NSCLC) intracranial metastases. PATIENTS AND METHODS: We performed a retrospective analysis of 28 patients undergoing resection of intracranial metastases and ART at our institution from 2001 to 2016. We assessed survival outcomes for patients who received delayed versus non-delayed ART, as well as associated risk factors. RESULTS: Among 28 patients, 8 (29%) had delayed ART beyond 6 post-operative weeks. Fifteen received stereotactic radiotherapy (SRT), 8 (29%) received whole brain radiotherapy (WBRT), and 5 (18%) received combination WBRT + SRT. There were no significant differences in ART modality or dosing, age, sex, number of intracranial metastases, primary metastasis volume, rates of chemotherapy, extracranial metastases, or post-operative functional scores between groups. Expected post-operative survival was shorter with delayed ART (7 months versus 28 months, P = 0.01). The most common reason for delayed ART was complicated post-operative course (n = 3.38%). Significant risk factors for delayed ART included non-routine discharge (P = 0.01) and additional invasive procedures between surgery and ART start date (P = 0.02). CONCLUSIONS: Our results suggest delayed ART in patients undergoing surgical resection of intracranial NSCLC metastases is associated with shorter overall survival. However, risk factors for delayed ART, including non-routine discharge and the need for additional invasive procedures, may have in themselves reflected poorer clinical courses that may have also contributed to the observed survival differences.

Surgery versus stereotactic radiosurgery for the treatment of multiple meningiomas in neurofibromatosis type 2: illustrative case and systematic review.

Neurofibromatosis type 2 (NF2) is a genetic neoplastic disorder that presents with hallmark bilateral vestibular schwannomas and multiple meningiomas. Though the current standard of care for meningiomas includes surgery, the multiplicity of meningiomas in NF2 patients renders complete resection of all developing lesions infeasible. Stereotactic radiosurgery (SRS) may be a viable non-invasive therapeutic alternative to surgery. We describe a particularly challenging case in a 39-year-old male with over 120 lesions who underwent more than 30 surgical procedures, and review the literature. We also searched three popular databases and compared outcomes of SRS versus surgery for the treatment of multiple meningiomas in patients with NF2. A total of 50 patients (27 radiosurgical and 23 surgical) were identified. For patients treated with SRS, local tumor control was achieved in 22 patients (81.5%) and distal control was achieved in 14 patients (51.8%). No malignant inductions were observed at an average follow-up duration of 90 months. Complications in the SRS-treated cohort were reported in 9 patients (33%). Eight patients (29.6%) died due to disease progression. Six patients experienced treatment failure and required further management. For NF2 patients treated with surgery, 11 patients (48%) showed tumor recurrence and 10 patients (43.5%) died due to neurological complications. SRS may be a safe and effective alternative for NF2-associated meningiomas. Further studies are required to identify the ideal radiosurgical candidate.

Survival Outcomes After Intracranial Hemorrhage in Liver Disease.

BACKGROUND: Survival outcomes for patients with liver disease who suffer an intracranial hemorrhage (ICH) have not been thoroughly investigated. OBJECTIVE: To understand survival outcomes for 3 groups: (1) patients with an admission diagnosis of liver disease (end-stage liver disease [ESLD] or non-ESLD) who developed an ICH in the hospital, (2) patients with ESLD who undergo either operative vs nonoperative management, and (3) patients with ESLD on the liver transplant waitlist who developed an ICH in the hospital. METHODS: We retrospectively reviewed hospital charts from March 2006 through February 2017 of patients with liver disease and an ICH evaluated by the neurosurgery service at a single academic medical center. The primary outcome was survival. RESULTS: We included a total of 53 patients in this study. The overall survival for patients with an admission diagnosis of liver disease who developed an ICH (n = 29, 55%) in the hospital was 22%. Of those patients with an admission diagnosis of liver disease, 27 patients also had ESLD. Kaplan-Meier analysis found no significant difference in survival for ESLD patients (n = 33, 62%) according to operative status. There were 11 ESLD patients on the liver transplant waitlist. The overall survival for patients with ESLD on the liver transplant waitlist who suffered an in-hospital ICH (n = 7, 13%) was 14%. CONCLUSION: ICH in the setting of liver disease carries a grave prognosis. Also, a survival advantage for surgical hematoma evacuation in ESLD patients is not clear.

Novel Method of Measuring Canal Dehiscence and Evaluation of its Potential as a Predictor of Symptom Outcomes After Middle Fossa Craniotomy.

BACKGROUND: Superior semicircular canal dehiscence (SSCD) is an osseous defect of the arcuate eminence of the petrous temporal bone. Strategies for measuring dehiscence size are variable, and the usefulness of such parameters remains in clinical equipoise. OBJECTIVE: To present a novel method of measuring dehiscence volume and to evaluate its potential as a predictor of symptom outcomes after surgical repair of SSCD. METHODS: High-resolution computed tomographic temporal bone images were imported into a freely available segmentation software. Dehiscence lengths and volumes were ascertained by independent authors. Inter-rater observer reliability was assessed using Cronbach's alpha. Correlation and regression analyses were performed to evaluate for relationships between dehiscence size and symptoms (pre- and post-operative). RESULTS: Thirty-seven dehiscences were segmented using the novel volumetric assessment. Cronbach's alpha for dehiscence lengths and volumes were 0.97 and 0.95, respectively. Dehiscence lengths were more variable as compared to dehiscence volumes (σ2 8.92 vs σ2 0.55, F = 1.74). The mean dehiscence volume was 2.22 mm3 (0.74, 0.64-0.53 mm3). Dehiscence volume and headache at presentation were positively correlated (Rpb = 0.67, P = .03). Dehiscence volume and vertigo improvement after surgery were positively correlated, although this did not reach statistical significance (Rpb = 0.46, P = .21). CONCLUSION: SSCD volumetry is a novel method of measuring dehiscence size that has excellent inter-rater reliability and is less variable compared to dehiscence length, but its potential as a predictor of symptom outcomes is not substantiated. However, the study is limited by low power.

Insights into CCL21's roles in immunosurveillance and immunotherapy for gliomas.

Chemokine (C-C) motif ligand 21 (CCL21) is involved in immunosurveillance and has recently garnered the attention of neuro-oncologists and neuroscientists. CCL21 contains an extended C-terminus, which increases binding to lymphatic glycosaminoglycans and provides a mechanism for cell trafficking by forming a stationary chemokine concentration gradient that allows cell migration via haptotaxis. CCL21 is expressed by endothelial cells of the blood-brain barrier in physiologic and pathologic conditions. CCL21 has also been implicated in leukocyte extravasation into the central nervous system. In this review, we summarize the role of CCL21 in immunosurveillance and explore its potential as an immunotherapeutic agent for the treatment of gliomas.

Central Neurocytoma: A Review of Clinical Management and Histopathologic Features.

Central neurocytoma (CN) is a rare, benign brain tumor often located in the lateral ventricles. CN may cause obstructive hydrocephalus and manifest as signs of increased intracranial pressure. The goal of treatment for CN is a gross total resection (GTR), which often yields excellent prognosis with a very high rate of tumor control and survival. Adjuvant radiosurgery and radiotherapy may be considered to improve tumor control when GTR cannot be achieved. Chemotherapy is also not considered a primary treatment, but has been used as a salvage therapy. The radiological features of CN are indistinguishable from those of other brain tumors; therefore, many histological markers, such as synaptophysin, can be very useful for diagnosing CNs. Furthermore, the MIB-1 Labeling Index seems to be correlated with the prognosis of CN. We also discuss oncogenes associated with these elusive tumors. Further studies may improve our ability to accurately diagnose CNs and to design the optimal treatment regimens for patients with CNs.