Transradial Versus Transfemoral Intraoperative Cerebral Angiography for Open Cerebrovascular Surgery: Effectiveness, Safety, and Learning Curve.

BACKGROUND: Intraoperative cerebral angiography (IOA) is a valuable adjunct in open and hybrid cerebrovascular surgery. Commonly, transfemoral access (TFA) is used. Lately, transradial access (TRA) has gained popularity for neurointervention. However, the TRA has not yet been compared with the TFA for IOA. OBJECTIVE: To compare the effectiveness and safety of the TRA and TFA for IOA. In addition, the learning curve for implementing the TRA for IOA was evaluated. METHODS: Between July 2020 and 2022, 92/1787 diagnostic cerebral angiographies met inclusion criteria for IOA. Sheath run time to primary target vessel run time (STT), amount of contrast dye (CD), fluoroscopy time (FT), and dose-area products (DAPs) were compared between TRA and TFA, different aortic arch types, and both study years. RESULTS: One case required transitioning from TRA to TFA (1/26, 3.8%) because of a minute proximal radial vasculature. The STT, CD, FT, and DAP were similar for the TRA (n = 25) and the TFA groups (n = 67) (p = ns). One groin hematoma (1.5%) was observed in the TFA group. No other complications or any change in modified Rankin Scale were observed. Aortic arch type II/III was associated with longer STT ( P = .032) but not CD, FT, or DAP. There was a nonsignificant decline of STTs among the TRA cases ( P = .104) but stable STTs among TFA cases ( P = .775). CONCLUSION: The TRA and TFA represent equally effective and safe routes for IOA. In addition, expertise with the TRA can rapidly be gained and facilitates tailoring the access for IOA to patient's individual anatomy and surgeon's needs.

Tenecteplase versus alteplase before mechanical thrombectomy: experience from a US healthcare system undergoing a system-wide transition of primary thrombolytic.

BACKGROUND: Tenecteplase (TNK) is a genetically modified variant of alteplase (TPA) and has been established as a non-inferior alternative to TPA in acute ischemic stroke (AIS). Whether TNK exerts distinct benefits in large vessel occlusion (LVO) AIS is still being investigated. OBJECTIVE: To describe our first-year experience after a healthcare system-wide transition from TPA to TNK as the primary thrombolytic. METHODS: Patients with AIS who received intravenous thrombolytics between January 2020 and August 2022 were retrospectively reviewed. All patients with LVO considered for mechanical thrombectomy (MT) were included in this analysis. Spontaneous recanalization (SR) after TNK/TPA was a composite variable of reperfusion >50% of the target vessel territory on cerebral angiography or rapid, significant neurological recovery averting MT. Propensity score matching (PSM) was performed to compare SR rates between TNK and TPA. RESULTS: A total of 148 patients were identified; 51/148 (34.5%) received TNK and 97/148 (65.5%) TPA. The middle cerebral arteries M1 (60.8%) and M2 (29.7%) were the most frequent occlusion sites. Baseline demographics were comparable between TNK and TPA groups. Spontaneous recanalization was significantly more frequently observed in the TNK than in the TPA groups (unmatched: 23.5% vs 10.3%, P=0.032). PSM substantiated the observed SR rates (20% vs 10%). Symptomatic intracranial hemorrhage, 90-day mortality, and functional outcomes were similar. CONCLUSIONS: The preliminary experience from a real-world setting demonstrates the effectiveness and safety of TNK before MT. The higher spontaneous recanalization rates with TNK are striking. Additional studies are required to investigate whether TNK is superior to TPA in LVO AIS.

Full Endoscopic Repair of Spontaneous Ventral Cerebrospinal Fluid Leaks in the Spine: Systematic Review of Surgical Treatment Options and Illustrative Case.

BACKGROUND: Spontaneous spinal cerebrospinal fluid (CSF) leaks are a rare entity that can lead to intracranial hypotension and associated headaches, meningismus, and patient debility. Surgical treatment may be necessary for patients who do not respond to conservative management. Surgical repair of CSF leaks located in the ventral thoracic spine traditionally require an invasive, open approach. METHODS: We describe the case of a patient with a ventral thoracic spontaneous spinal CSF leak associated with a ventral bony osteophyte successfully treated with spinal endoscopy. We also provide a systematic review of the literature to better understand outcomes of this approach. RESULTS: A total of 55 patients were included in the systematic review. The study designs found in the literature review included case reports (66.7%), retrospective cohorts (22.2%), and prospective cohorts (11.1%). Of the studies reporting data, 50% of studies stated they used an open posterior approach to the dural defect, while 37.5% reported using an open anterior approach to the pathology. Only 1 (12.5%) study reported using an endoscope. Most studies (62.5%) used primary closure of the dura in their technique, while 37.5% reported using a local tissue graft (fat or muscle) or a dural sealant for their closure technique, and 25% of studies reported using a dural substitute for their closure technique. Overall mean clinical follow-up was 19.8 months. CONCLUSIONS: The endoscopic approach described here for treatment of this rare entity allows for removal of bony spicules/osteophytes and dural repair without the morbidity associated with traditional open dorsolateral or ventrolateral approaches.

Outcomes of Interventional-MRI Versus Microelectrode Recording-Guided Subthalamic Deep Brain Stimulation.

In deep brain stimulation (DBS) of the subthalamic nucleus (STN) for Parkinson's disease (PD), there is debate concerning the use of neuroimaging alone to confirm correct anatomic placement of the DBS lead into the STN, versus the use of microelectrode recording (MER) to confirm functional placement. We performed a retrospective study of a contemporaneous cohort of 45 consecutive patients who underwent either interventional-MRI (iMRI) or MER-guided DBS lead implantation. We compared radial lead error, motor and sensory side effect, and clinical benefit programming thresholds, and pre- and post-operative unified PD rating scale scores, and levodopa equivalent dosages. MER-guided surgery was associated with greater radial error compared to the intended target. In general, side effect thresholds during initial programming were slightly lower in the MER group, but clinical benefit thresholds were similar. No significant difference in the reduction of clinical symptoms or medication dosage was observed. In summary, iMRI lead implantation occurred with greater anatomic accuracy, in locations demonstrated to be the appropriate functional region of the STN, based on the observation of similar programming side effect and benefit thresholds obtained with MER. The production of equivalent clinical outcomes suggests that surgeon and patient preference can be used to guide the decision of whether to recommend iMRI or MER-guided DBS lead implantation to appropriate patients with PD.

Use of the Apollo detachable-tip microcatheter for endovascular embolization of arteriovenous malformations and arteriovenous fistulas.

OBJECTIVE: Liquid embolic agents have revolutionized endovascular management of arteriovenous malformations (AVMs) and arteriovenous fistulas (AVFs). Nonetheless, since 2005, the US FDA has received more than 100 reports of microcatheter breakage or entrapment related to Onyx embolization, including 9 deaths. In 2014, the Apollo detachable-tip microcatheter became the first of its kind available in the US. Since then, few reports on its safety have been published. METHODS: The authors conducted a retrospective review of endovascular cases by searching the patient databases at 2 tertiary cerebrovascular centers (Barrow Neurological Institute and University of Pittsburgh Medical Center). Patients who underwent endovascular embolization of an AVM or AVF using the Apollo microcatheter were identified. Patient demographics and lesion characteristics were collected. The authors analyzed Apollo-specific endovascular variables, such as number of microcatheterizations, sessions, and pedicles embolized; microcatheter tip detachment status; obliteration rate; and endovascular- and microcatheter-related morbidity and mortality. RESULTS: From July 2014 to October 2016, a total of 177 embolizations using the Apollo microcatheter were performed in 61 patients (mean age 40.3 years). The most frequent presentation was hemorrhage (22/61, 36.1%). Most lesions were AVMs (51/61, 83.6%; mean diameter 30.6 mm). The mean Spetzler-Martin grade was 2.4. Thirty-nine (76.5%) of 51 patients with AVMs underwent resection. Microcatheterization was successful in 172 pedicles. Most patients (50/61, 82%) underwent a single embolization session. The mean number of pedicles per session was 2.5 (range 1-7). Onyx-18 was used in 103 (59.9%), N-butyl cyanoacrylate (NBCA) in 44 (25.6%), and Onyx-34 in 25 (14.5%) of the 172 embolizations. In 45.9% (28/61) of the patients, lesion obliteration of 75% or greater was achieved. Tip detachment occurred in 19.2% (33/172) of microcatheters. Fifty-three (86.9%) of the 61 patients who underwent embolization with the Apollo microcatheter had good functional outcomes (modified Rankin Scale score 0-2). No unintended microcatheter fractures or related morbidity was observed. One patient died of intraprocedural complications unrelated to microcatheter selection. In the univariate analysis, microcatheter tip detachment (p = 0.12), single embolized pedicles (p = 0.12), and smaller AVM nidus diameter (p = 0.17) correlated positively with high obliteration rates (> 90%). In the multivariate analysis, microcatheter tip detachment was the only independent variable associated with high obliteration rates (OR 9.5; p = 0.03). CONCLUSIONS: The use of the Apollo detachable-tip microcatheter for embolization of AVMs and AVFs is associated with high rates of successful catheterization and obliteration and low rates of morbidity and mortality. The microcatheter was retrieved in all cases, even after prolonged injections in distal branch pedicles, often with significant reflux. This study represents the largest case series on the application of the Apollo microcatheter for neurointerventional procedures.

Comparison of prognostic indices in patients who undergo melanoma brain metastasis radiosurgery.

OBJECTIVE The goal of this study was to use 4 prognostic indices to compare survival times of patients who underwent Gamma Knife stereotactic radiosurgery (SRS) to treat melanoma brain metastases. METHODS The authors analyzed 422 consecutive patients (1440 brain metastases) who underwent Gamma Knife SRS. The median total brain tumor volume was 4.7 cm3 (range 0.3-69.3 cm3), and the median number of metastases was 2 (range 1-32). One hundred thirty-two patients underwent whole-brain radiation therapy. Survival times were compared using recursive partitioning analysis (RPA), the Score Index for Radiosurgery (SIR), the Basic Score for Brain Metastases (BSBM), and the Diagnosis-Specific Graded Prognostic Assessment (DS-GPA). RESULTS The overall survival times after SRS were compared. With the RPA index, survival times were 2.6 months (Class III, n = 27), 5.5 months (Class II, n = 348), and 13.0 months (Class I, n = 47). With the DS-GPA index, survival times were 2.8 months (Scores 0-1, n = 67), 4.2 months (Scores 1.5-2.0, n = 143), 6.6 months (Scores 2.5-3.0, n = 111), and 9.4 months (Scores 3.5-4.0, n = 101). With the SIR, survival times were 3.2 months (Scores 0-3, n = 56), 5.8 months (Scores 4-7, n = 319), and 12.7 months (Scores 8-10, n = 47). With the BSBM index, survival times were 2.6 months (BSBM0, n = 47), 5.4 months (BSBM1, n = 282), 11.0 months (BSBM2, n = 86), and 8.8 months (BSBM3, n = 7). The DS-GPA index was the most balanced by case numbers in each class and provided the overall best prognostic index for overall survival. CONCLUSIONS The DS-GPA index proved most balanced and predictive of survival for patients with melanoma who underwent SRS as part of management for brain metastases. Patients whose DS-GPA score was ≥ 2.5 had predictably improved survival times after SRS.

Limitations of multidetector computed tomography angiography for the diagnosis of blunt cerebrovascular injury.

OBJECTIVE Blunt cerebrovascular injuries (BCVIs) following trauma carry risk for morbidity and mortality. Since patients with BCVI are often asymptomatic at presentation and neurological sequelae often occur within 72 hours, timely diagnosis is essential. Multidetector CT angiography (CTA) has been shown to be a noninvasive, cost-effective, reliable means of screening; however, the false-positive rate of CTA in diagnosing patients with BCVI represents a key drawback. Therefore, the authors assessed the role of DSA in the screening of BCVI when utilizing CTA as the initial screening modality. METHODS The authors performed a retrospective analysis of patients who experienced BCVI between 2013 and 2015 at 2 Level I trauma centers. All patients underwent CTA screening for BCVI according to the updated Denver Screening Criteria. Patients who were diagnosed with BCVI on CTA underwent confirmatory digital subtraction angiography (DSA). Patient demographics, screening indication, BCVI grade on CTA and DSA, and laboratory values were collected. Comparison of false-positive rates stratified by BCVI grade on CTA was performed using the chi-square test. RESULTS A total of 140 patients (64% males, mean age 50 years) with 156 cerebrovascular blunt injuries to the carotid and/or vertebral arteries were identified. After comparison with DSA findings, CTA findings were incorrect in 61.5% of vessels studied, and the overall CTA false-positive rates were 47.4% of vessels studied and 47.9% of patients screened. The positive predictive value (PPV) for CTA was higher among worse BCVI subtypes on initial imaging (PPV 76% and 97%, for BCVI Grades II and IV, respectively) compared with Grade I injuries (PPV 30%, p < 0.001). CONCLUSIONS In the current series, multidetector CTA as a screening test for blunt cerebrovascular injury had a high-false positive rate, especially in patients with Grade I BCVI. Given a false-positive rate of 47.9% with an estimated average of 132 patients per year screening positive for BCVI with CTA, approximately 63 patients per year would potentially be treated unnecessarily with antithrombotic therapy at a busy United States Level I trauma center. The authors' data support the use of DSA after positive findings on CTA in patients with suspected BCVI. DSA as an adjunctive test in patients with positive CTA findings allows for increased diagnostic accuracy in correctly diagnosing BCVI while minimizing risk from unnecessary antithrombotic therapy in polytrauma patients.

A Critical Analysis of the Utility of Intraoperative Angiography.

OBJECTIVE: Intraoperative digital subtraction angiography (ioDSA) is touted as the gold standard imaging evaluation for aneurysm clip constructs. Candid evaluations of its limitations are sparse. METHODS: A prospectively collected hospital billing database was queried to identify craniotomies for aneurysm clipping from January 2010 to December 2013. We evaluated the rate of occult residual and parent vessel stenosis determined on follow-up angiography for patients undergoing ioDSA and those not undergoing ioDSA. Comparisons were performed via Fisher exact test, with P < 0.05 considered statistically significant. RESULTS: From our database search, we found 187 patients who underwent ioDSA after aneurysm clipping and an additional 91 patients who did not. Results from ioDSA influenced operative management in 17% of cases. Sixty-four patients with 70 treated aneurysms undergoing ioDSA had postoperative angiography; 7 occult residuals were discovered, yielding a 10% false-negative rate, with 10% of aneurysms showing residual. Occult residuals at the middle cerebral artery bifurcation represented most discovered residuals (6/7). Thirty-two patients with 37 treated aneurysms did not undergo ioDSA and had angiographic follow-up; 24% of patients were found to have residual aneurysms (P = 0.08 compared with patients undergoing ioDSA). Residuals at the anterior communicating artery (ACoA) represented 56% of all residuals, whereas the ACoA represented only 18% of aneurysms clipped. The rate of residuals was significantly higher than that for patients with clipped ACoA aneurysms undergoing ioDSA (P = 0.008). CONCLUSIONS: ioDSA influenced management in nearly one fifth of cases. It can be particularly beneficial in detecting residuals for ACoA aneurysms; its benefit was less apparent for middle cerebral artery aneurysms.

Diagnostic Accuracy of Somatosensory Evoked Potential Monitoring in Evaluating Neurological Complications During Endovascular Aneurysm Treatment.

BACKGROUND: Somatosensory evoked potential (SSEP) monitoring is used extensively for early detection and prevention of neurological complications in patients undergoing many different neurosurgical procedures. However, the predictive ability of SSEP monitoring during endovascular treatment of cerebral aneurysms is not well detailed. OBJECTIVE: To evaluate the performance of intraoperative SSEP in the prediction postprocedural neurological deficits (PPNDs) after coil embolization of intracranial aneurysms. METHODS: This population-based cohort study included patients ≥18 years of age undergoing intracranial aneurysm embolization with concurrent SSEP monitoring between January 2006 and August 2012. The ability of SSEP to predict PPNDs was analyzed by multiple regression analyses and assessed by the area under the receiver operating characteristic curve. RESULTS: In a population of 888 patients, SSEP changes occurred in 8.6% (n = 77). Twenty-eight patients (3.1%) suffered PPNDs. A 50% to 99% loss in SSEP waveform was associated with a 20-fold increase in risk of PPND; a total loss of SSEP waveform, regardless of permanence, was associated with a greater than 200-fold risk of PPND. SSEPs displayed very good predictive ability for PPND, with an area under the receiver operating characteristic curve of 0.84 (95% CI 0.76-0.92). CONCLUSION: This study supports the predictive ability of SSEPs for the detection of PPNDs. The magnitude and persistence of SSEP changes is clearly associated with the development of PPNDs. The utility of SSEP monitoring in detecting ischemia may provide an opportunity for neurointerventionalists to respond to changes intraoperatively to mitigate the potential for PPNDs.

Transosseous cerebrospinal fluid fistula 14 years after Chiari decompression: presentation and management.

The authors report a unique case of a transosseous CSF fistula that was detected more than 10 years after treatment of a symptomatic Chiari I malformation. This lesion initially presented as an intraosseous cystic lesion involving the C-2 vertebra, which was found to communicate freely with the subarachnoid space through a tiny dural opening. Surgical management involved hemilaminectomy and repair of the dural defect followed by reinforcement of the bony defect with demineralized bone matrix. Following closure of the fistula, symptoms of elevated intracranial pressure developed, necessitating a ventriculoperitoneal shunt for CSF diversion.

Vaginal extrusion of a ventriculo-peritoneal shunt catheter in an adult.

Ventriculo-peritoneal shunts (VPS) are commonly used in the treatment of various neurosurgical conditions, including hydrocephalus and pseudotumor cerebri. We report only the second case of vaginal extrusion of a VPS catheter in an adult, and the first case with a modern VPS silastic peritoneal catheter. A 45-year-old female with a history of VPS for pseudotumor cerebri, Behcet's syndrome, and hysterectomy presented to our institution with the chief complaint of tubing protruding from her vagina after urination. On gynecologic examination, the patient was found to have approximately 15 cm of VPS catheter protruding from her vaginal apex. A computed tomography scan of the abdomen and shunt X-ray series demonstrated no breaks in the tubing, but also confirmed the finding of the VPS catheter extruding through the vaginal cuff into the vagina. The patient had the VPS removed and an external ventricular drain was placed for temporary cerebrospinal fluid diversion. Ventricular catheter cultures were positive for diphtheroids. After an appropriate course of antibiotics, a contralateral ventriculo-pleural shunt was placed one week later. Although vary rare, vaginal extrusion can occur in adults, even with modern VPS catheters.

Cervical and cervicomedullary spinal cord stimulation for chronic pain: efficacy and outcomes.

BACKGROUND: The role for spinal cord stimulation (SCS) in the management of chronic spinal cord forms of pain involving cervical dermatomes or the cervicomedullary junction (CMJ) for facial pain remains largely uncharted. OBJECTIVE: To review outcomes with cervical and CMJ SCS performed by a single surgeon, with particular emphasis on complications and efficacy. METHODS: All patients that underwent cervical or CMJ SCS by the lead author were identified and follow-up obtained by telephone questionnaires. Patient demographics, surgical details, outcomes and complications for all patients identified were critically reviewed. RESULTS: Of 121 patients identified that underwent at least trial SCS, 100 underwent permanent lead implantation. Indications for cervical SCS included brachial plexus lesions (8), complex regional pain syndrome (33), degenerative disc disease (4), failed neck surgery syndrome (23), chronic radiculopathy (6) and post-herpetic neuralgia (PHN) (1); for CMJ SCS, indications included trigeminal deafferetiation pain (10), trigeminal neuropathic pain (4), PHN (4) and occipital neuralgia (7). Pain relief was greater along the extremities than axially, and less in the occipital area than in the head or face. Mean pain reduction averaged 56.6% at a mean follow-up of 4.2 years. Of 24 revision surgeries required, 8 were for presumed lead migration or fracture. Complications included 4 CSF leaks, 5 wound infections, and 4 cases of persistent numbness or pain. Pain relief lasted an average of 3.6 years. CONCLUSION: Cervical and CMJ SCS are safe and efficacious and may provide greater relief along the upper extremities than axially, and in the head rather than in the occipital region.

Volumetric response to radiosurgery for brain metastasis varies by cell of origin.

OBJECT: The aim of this study was to evaluate the imaging response of brain metastases after radiosurgery and to correlate the response with tumor type and patient survival. METHODS: The authors conducted a retrospective review of patients who had undergone Gamma Knife radiosurgery for brain metastases from non-small cell lung cancer (NSCLC), breast cancer, or melanoma. The imaging volumetric response by tumor type was plotted at 3-month intervals and classified as a sustained decrease in tumor volume (Type A), a transient decrease followed by a delayed increase in tumor volume (Type B), or a sustained increase in tumor volume (Type C). These imaging responses were then compared with patient survival and tumor type. RESULTS: Two hundred thirty-three patients with metastases from NSCLC (96 patients), breast cancer (98 patients), and melanoma (39 patients) were eligible for inclusion in this study. The patients with NSCLC were most likely to exhibit a Type A response; those with breast cancer, a Type B response; and those with melanoma, a Type C response. Among patients with NSCLC, the median overall survival was 11.2 months for those with a Type A response (76 patients), 8.6 months for those with a Type B response (6 patients), and 10.5 months for those with a Type C response (14 patients). Among patients with breast cancer, the median overall survival was 16.6 months in those with a Type A response (65 patients), 18.1 months in those with a Type B response (20 patients), and 7.5 months in those with a Type C response (13 patients). For patients with melanoma, the median overall survival was 5.2 months in those with a Type A response (26 patients) and 6.7 months in those with a Type C response (13 patients). None of the patients with melanoma had a Type B response. The imaging response was significantly associated with survival only in patients with breast cancer. CONCLUSIONS: The various types of imaging responses of metastatic brain tumors after stereotactic radiosurgery depend in part on tumor type. However, the type of response only correlates with survival in patients with breast cancer.

The early days of hemostasis in neurosurgery.

Two key discoveries in the 19th century--infection control and the development of general anesthesia--provided an impetus for the rapid advancement of surgery, especially within the field of neurosurgery. Yet the field of neurosurgery would not have existed in the modern sense without the development and advancement of techniques in hemostasis. Improvement in intraoperative hemostasis came more gradually but was no less important to enhancing neurosurgical outcomes. The history of hemostasis in neurosurgery is often overlooked. Herein, the authors briefly review the historical progression of hemostatic techniques since the beginning of the early modern era of neurosurgery.

Decompressive craniectomy for elevated intracranial pressure and its effect on the cumulative ischemic burden and therapeutic intensity levels after severe traumatic brain injury.

BACKGROUND: Increased intracranial pressure (ICP) can cause brain ischemia and compromised brain oxygen (PbtO2 < or = 20 mm Hg) after severe traumatic brain injury (TBI). OBJECTIVE: We examined whether decompressive craniectomy (DC) to treat elevated ICP reduces the cumulative ischemic burden (CIB) of the brain and therapeutic intensity level (TIL). METHODS: Ten severe TBI patients (mean age, 31.4 +/- 14.2 years) who had continuous PbtO2 monitoring before and after delayed DC were retrospectively identified. Patients were managed according to the guidelines for the management of severe TBI. The CIB was measured as the total time spent between a PbtO2 of 15 to 20, 10 to 15, and 0 to 10 mm Hg. The TIL was calculated every 12 hours. Mixed-effects models were used to estimate changes associated with DC. RESULTS: DC was performed on average 2.8 days after admission. DC was found to immediately reduce ICP (mean [SEM] decrease was 7.86 mm Hg [2.4 mm Hg]; P = .005). TIL, which was positively correlated with ICP (r = 0.46, P < or = .001), was reduced within 12 hours after surgery and continued to improve within the postsurgical monitoring period (P