The diagnostic accuracy of neuromonitoring for detecting postoperative bowel and bladder dysfunction in spinal oncology surgery: a case series.

PURPOSE: Postoperative bowel and bladder dysfunction (BBD) poses a significant risk following surgery of the sacral spinal segments and sacral nerve roots, particularly in neuro-oncology cases. The need for more reliable neuromonitoring techniques to enhance the safety of spine surgery is evident. METHODS: We conducted a case series comprising 60 procedures involving 56 patients, spanning from September 2022 to January 2024. We assessed the diagnostic accuracy of sacral reflexes (bulbocavernosus and external urethral sphincter reflexes) and compared them with transcranial motor evoked potentials (TCMEP) incorporating anal sphincter (AS) and external urethral sphincter (EUS) recordings, as well as spontaneous electromyography (s-EMG) with AS and EUS recordings. RESULTS: Sacral reflexes demonstrated a specificity of 100% in predicting postoperative BBD, with a sensitivity of 73.33%. While sensitivity slightly decreased to 64.71% at the 1-month follow-up, it remained consistently high overall. TCMEP with AS/EUS recordings did not identify any instances of postoperative BBD, whereas s-EMG with AS/EUS recordings showed a sensitivity of 14.29% and a specificity of 97.14%. CONCLUSION: Sacral reflex monitoring emerges as a robust adjunct to routine neuromonitoring, offering surgeons valuable predictive insights to potentially mitigate the occurrence of postoperative BBD.

Occipital venous sinus stenting for idiopathic intracranial hypertension and pulsatile tinnitus: A case series.

Venous sinus stenting for dural venous sinus outflow obstruction due to an intrinsic filling obstruction or extrinsic stenosis is an increasingly popular treatment strategy for idiopathic intracranial hypertension (IIH) and isolated pulsatile tinnitus (PT). The most common site of stenosis is the lateral venous sinus at the transverse-sigmoid junction. Approximately 10% of the population has a persistent occipital venous sinus (OVS), a variant that may be the dominant venous drainage pathway in the setting of a hypoplastic or aplastic transverse sinus. OVS stenosis has been rarely associated with IIH and isolated PT with only a handful published cases. We herein report a retrospective series of OVS stenting in five patients, four of whom presented with non-IIH PT and one with IIH.

The role of surgical disconnection for posterior fossa pial arteriovenous fistulas and dural fistulas with pial supply: an illustrative case series.

BACKGROUND: Pial arteriovenous fistulas (pAVFs) are rare vascular malformations characterized by high-flow arteriovenous shunting involving a cortical arterial supply directly connecting to venous drainage without an intermediate nidus. Dural arteriovenous fistulas (dAVFs) can infrequently involve additional pial feeders which can introduce higher flow shunting and increase the associated treatment risk. In the posterior fossa, arteriovenous fistula (AVF) angioarchitecture tends to be particularly complex, involving either multiple arterial feeders-sometimes from both dural and pial origins-or small caliber vessels that are difficult to catheterize and tend to be intimately involved with functionally critical brainstem or upper cervical cord structures. Given their rarity, published experience on microsurgical or endovascular treatment strategies for posterior fossa pAVFs and dAVFs with pial supply remains limited. METHODS: Retrospective chart review from 2019-2023 at a high-volume center identified six adult patients with posterior fossa pAVFs that were unable to be fully treated endovascularly and required microsurgical disconnection. These cases are individually presented with a technical emphasis and supported by comprehensive angiographic and intraoperative images. RESULTS: One vermian (Case 1), three cerebellopontine angle (Cases 2-4) and two craniovertebral junction (Cases 5-6) posterior fossa pAVFs or dAVFs with pial supply are presented. Three cases involved mixed dural and pial arterial supply (Cases 1, 4, and 6), and one case involved a concomitant microAVM (Case 2). Endovascular embolization was attempted in four cases (Cases 1-4): The small caliber and tortuosity of the main arterial feeder prevented catheterization in two cases (Cases 1 and 3). Partial embolization was achieved in Cases 2 and 4. In Cases 5 and 6, involvement of the lateral spinal artery or anterior spinal artery created a prohibitive risk for endovascular embolization, and surgical clip ligation was pursued as primary management. In all cases, microsurgical disconnection resulted in complete fistula obliteration without evidence of recurrence on follow-up imaging (mean follow-up 27.1 months). Two patients experienced persistent post-treatment sensory deficits without significant functional limitation. CONCLUSIONS: This illustrative case series highlights the technical difficulties and anatomical limitations of endovascular management for posterior fossa pAVFs and dAVFs with pial supply and emphasizes the relative safety and utility of microsurgical disconnection in this context. A combined approach involving partial preoperative embolization-when the angioarchitecture is permissive-can potentially decrease surgical morbidity. Larger studies are warranted to better define the role for multimodal intervention and to assess associated long-term AVF obliteration rates in the setting of pial arterial involvement.

Eclipse balloon-assisted straight sinus thrombectomy: A novel technique.

Cerebral venous sinus thrombosis comprises 0.5% of all strokes and usually affects young adults. Straight sinus involvement is relatively rare, and it is associated with poor prognosis. Intravenous anticoagulation is considered the first line of treatment. Endovascular approaches such as direct catheter thrombolysis, balloon-assisted thrombolysis, and mechanical thrombectomy may be more efficient and should be considered in cases in which there is involvement of the deep venous system, declining neurological status, or less invasive treatment options have failed. In this work, we describe a novel technique of ECLIPSE 2L balloon (Balt, Irvine, CA) assisted mechanical thrombectomy for straight sinus thrombosis and a review of dural sinus thrombosis management.

Single-center outcomes of Onyx Frontier™ and Resolute Onyx™ drug-eluting balloon-mounted stents for rescue stenting for acute large vessel occlusion.

BACKGROUND: In cases where mechanical thrombectomy (MT) fails, rescue stenting may be necessary to achieve reperfusion; however, the lack of standardized techniques or devices poses a challenge. This series aims to present our early experience with the Onyx Frontier™ and Resolute Onyx™ balloon-mounted drug-eluting stents for rescue stenting. METHODS: A retrospective chart review was performed of all patients who underwent rescue stenting, in the setting of failed MT, using Onyx Frontier™ or Resolute Onyx™ stents at a single institution. Technical details, procedural complications, and patient outcomes were recorded for each case. RESULTS: Twenty-two Onyx Frontier™ and Resolute Onyx™ stents were deployed in 18 patients undergoing rescue stenting. Stent locations included the middle cerebral artery (36.4%), internal carotid artery (18.2%), vertebral artery (22.7%), and basilar artery (22.7%). The average National Institutes of Health Stroke Scale score before MT was 13.8 (range 0-31). The median initial modified Rankin Scale (mRS) score was zero, while the median mRS score at follow-up was three. Successful reperfusion, as assessed by TICI scores, was achieved in 43.8% of patients for TICI 3, 43.8% for TICI 2C, and 12.5% for TICI 2B. Post-revascularization, 16.7% of patients experienced hemorrhage, of which one patient (5.6%) had symptomatic hemorrhage. CONCLUSIONS: Onyx Frontier™ and Resolute Onyx™ stents are well suited for rescue stenting in cases of failed MT. These balloon-mounted drug-eluting stents exhibit excellent navigability, rendering them appropriate for rescue revascularization procedures. Our findings demonstrate that these stents confer a high degree of technical success.

Characterizing complications associated with skull clamps: A review of the manufacturer and user facility device experience database.

OBJECTIVE: Head immobilization with skull clamps is a prerequisite of many neurosurgical procedures. Adverse events relating to the use of skull clamps have been reported, however, given the paucity of published reports, we sought to conduct a more comprehensive analysis using the Manufacturer and User Facility Device Experience (MAUDE) database. METHODS: The MAUDE database was queried for neurosurgical skull clamp events over a 10-year period between January 2013 and December 2022. Reports were qualitatively analyzed and categorically assigned by the study authors as 'mechanical failure,' 'slippage,' 'contamination,' 'insufficient information,' and 'other.' Patient injury reports were also classified as 'abrasion,' 'laceration,' 'hematoma,' 'fracture,' 'intracranial hemorrhage (ICH),' 'other,' 'insufficient information,' and 'death.' RESULTS: Of 3672 reports retrieved, 2689 (73.2%) were device malfunctions, with mechanical failure (50.7%) and slippage (47.7%) being the most common causes. There were 983 reports (26.8%) involving patient injury which included lacerations (n = 776, 78.9%), fractures (n = 24, 2.4%), abrasions (n = 23, 2.3%), hematomas (n = 7, 0.71%), ICH (n = 3, 0.31%), and other causes (n = 6, 0.61%). Five (0.1%) deaths due to skull clamp related complications were also reported. CONCLUSIONS: This study provides a more comprehensive picture of adverse events in neurosurgical procedures relating to the use of skull clamps. Mechanical failures of device parts were the most common device-related complication, and lacerations the most common adverse patient-related event. While more severe patient-related events were reported, they are relatively rare. The MAUDE database is useful for characterizing underreported device-related and patient-related adverse events.

Endoscopic Third Ventriculostomy Using Penumbra Artemis™ Neuro Evacuation Device: Technical Case Report and Operative Video.

Endoscopic third ventriculostomy (ETV) is an effective cerebrospinal fluid diversion procedure but can be complicated by the presence of a high-riding basilar artery (BA). A 70-year-old female presented with obstructive hydrocephalus caused by melanoma metastatic to the brainstem in the setting of a high-riding BA. ETV was successfully performed using the Penumbra Artemis™ Neuro evacuation device (Artemis; Penumbra Inc, Alameda, CA, USA) to minimize the risk of injury to the BA. This is to our knowledge the first known Artemis-assisted ETV reported in the English literature, which may reduce the risk of BA injury in selected patients. Further characterization of the benefits and limitations of this procedure is needed.

Ventral Spinal Cord Herniation Causing Spinal Intradural Hematoma and Subarachnoid Hemorrhage: A Case Report.

Ventral spinal cord herniation is a rare pathology, caused by a dural defect, that leads to progressive myelopathy. The true prevalence of ventral spinal cord herniation is unknown largely because of underdiagnosis due to its nonspecific symptoms. Though there are theories that attempt to describe how these dural defects are formed, the true causes of these defects are unknown. In this case report, we present a case of a 29-year-old female who had an idiopathic ventral spinal cord herniation causing an intradural hematoma and subarachnoid hemorrhage. This is the first reported case of spinal cord herniation causing hemorrhage.

Needle Parking Interrupted Suturing Technique for Microvascular Anastomosis: A Technical Note.

BACKGROUND: Interrupted and continuous suturing are 2 common techniques for microvascular anastomosis in cerebrovascular surgery. One of the technical complexities of interrupted suturing includes the risk of losing the needle in between interrupted sutures during knot tying, which may result in unnecessary movements and wasted time. OBJECTIVE: To report a new needle parking technique for microvascular anastomosis that addresses a needle control problem during interrupted suturing. METHODS: The needle parking technique involves puncturing both vessel walls at the site of the next provisional suture and leaving the needle parked in place while the knots at the first suture are being made. The thread is then cut, the needle is pulled through, and the process is repeated. Illustrative cases in which the needle parking technique was used are presented. We also compared time of anastomosis completion between the conventional interrupted, needle parking interrupted, and continuous suturing techniques during an in vitro study on standardized artificial vessels. RESULTS: This technique is being used successfully by the senior author for various cerebrovascular bypass surgeries. The in vitro study demonstrated that the needle parking technique can be significantly faster than the conventional interrupted suturing technique and may be as fast as continuous suturing. CONCLUSION: Needle parking technique is a modification of conventional interrupted suturing and solves the problem of losing the needle during knot tying. This technique is simple, prevents unnecessary movements, and may result in a faster anastomosis time.

Implantable Pulse Generator Site May Be Associated With Spinal Cord Stimulation Revision Surgeries.

BACKGROUND: The use of implantable pulse generators (IPG) for spinal cord stimulation (SCS) in patients with chronic pain has been well established. Although IPG-related complications have been reported on, the association between IPG site and SCS complications has not been well studied. OBJECTIVE: To investigate whether IPG placement site in buttock or flank is associated with SCS complications and, hence, revision surgeries. METHOD: A retrospective cohort study was performed that included 330 patients (52% female) treated at a single institution who underwent permanent implantation of an SCS system between 2014 and 2018. Patients ranged between 20 and 94 years of age (mean: 57.54 ± 13.25). Statistical analyses were conducted using IBM SPSS Statistics. Tests included independent samples t test, chi-square test, Mann-Whitney U test, Spearman's rank correlation coefficient, and logistic regression. RESULTS: There was a total of 93 revision surgeries (rate of 28%), where 71 out of 330 patients (rate of 21.5%) had had at least one revision surgery. Univariate tests demonstrated a significant association between IPG site and revision surgeries (p = 0.028 [chi-square test] and p = 0.031 [Mann-Whitney U test]); however, multivariate logistic regression demonstrated that neither IPG site was more likely than the other to require revision surgeries (p = 0.286). CONCLUSION: Although this study found a significant association between IPG site and revision surgeries, the effect of IPG site was not found to be predictive. The IPG site likely influences whether a patient will require revision surgery, but further investigation is required to establish this association.

Robot-Assisted Stereotaxy Reduces Target Error: A Meta-Analysis and Meta-Regression of 6056 Trajectories.

BACKGROUND: The pursuit of improved accuracy for localization and electrode implantation in deep brain stimulation (DBS) and stereoelectroencephalography (sEEG) has fostered an abundance of disparate surgical/stereotactic practices. Specific practices/technologies directly modify implantation accuracy; however, no study has described their respective influence in multivariable context. OBJECTIVE: To synthesize the known literature to statistically quantify factors affecting implantation accuracy. METHODS: A systematic review and meta-analysis was conducted to determine the inverse-variance weighted pooled mean target error (MTE) of implanted electrodes among patients undergoing DBS or sEEG. MTE was defined as Euclidean distance between planned and final electrode tip. Meta-regression identified moderators of MTE in a multivariable-adjusted model. RESULTS: A total of 37 eligible studies were identified from a search return of 2,901 potential articles (2002-2018) - 27 DBS and 10 sEEG. Random-effects pooled MTE = 1.91 mm (95% CI: 1.7-2.1) for DBS and 2.34 mm (95% CI: 2.1-2.6) for sEEG. Meta-regression identified study year, robot use, frame/frameless technique, and intraoperative electrophysiologic testing (iEPT) as significant multivariable-adjusted moderators of MTE (P < .0001, R2 = 0.63). Study year was associated with a 0.92-mm MTE reduction over the 16-yr study period (P = .0035), and robot use with a 0.79-mm decrease (P = .0019). Frameless technique was associated with a mean 0.50-mm (95% CI: 0.17-0.84) increase, and iEPT use with a 0.45-mm (95% CI: 0.10-0.80) increase in MTE. Registration method, imaging type, intraoperative imaging, target, and demographics were not significantly associated with MTE on multivariable analysis. CONCLUSION: Robot assistance for stereotactic electrode implantation is independently associated with improved accuracy and reduced target error. This remains true regardless of other procedural factors, including frame-based vs frameless technique.

Current and future perspectives on the treatment of cerebral ischemia.

INTRODUCTION: After heart disease and combined forms of cancer, stroke is the leading cause of death in the United States. Currently, tissue-plasminogen activator (tPA) thrombolysis is the only thrombolytic therapy that has been shown to improve patient outcome. Presently, the only antithrombotic drug treatment that has proven effective at improving acute ischemic stroke patient outcome is aspirin administration. Despite these studies, no clinical trials have yet demonstrated a reliably effective pharmacological treatment. Areas covered: We conducted a search of recent drug studies for ischemic stroke on clinicaltrials.gov in addition to a literature search for acute ischemic stroke therapy using PubMed. This review details our findings of recent advancements in the pharmacological treatment of acute ischemic stroke. Expert commentary: We concluded that recent attempts to establish new pharmacological treatment protocols for acute ischemic stroke have had limited success, but many Phase III and Phase IV clinical trials demonstrate promise. Moreover, several studies have demonstrated the efficacy of dual-antiplatelet therapies at reducing risk of secondary stroke. Studies for novel therapeutic targets for neuroprotection have been largely unsuccessful. Some trials had positive results; however, there is much room for improvement and other studies show promise in their preliminary stages.