Jugular venous narrowing and spontaneous spinal cerebrospinal fluid leaks: A case-control study exploring association and proposed mechanism.

BACKGROUND: Spontaneous skull base cerebrospinal fluid leaks (CSFLs) are associated with increased intracranial pressure in idiopathic intracranial hypertension (IIH) and hypothesized to relate to skull base erosions due to increased CSF pressure. Given the increasing recognition of internal jugular venous stenosis (IJVS) as a cause of intracranial hypertension (IH), we evaluated the relationship between spinal CSFL and venous causes of IH. METHODS: The spinal CSFL database at a single institution was assessed to identify 12 consecutive spontaneous, non-traumatic spinal CSFL patients with CTV data. Exclusion criteria included documented IIH and iatrogenic CSFL. Demographics, clinical parameters, imaging characteristics, and IJV manometry results were recorded. Internal jugular venous stenosis was graded as: none (0-10%), mild (10-50%), moderate (50-80%), severe (>80-99%), and occluded (100%). Twelve consecutive patients who presented with cerebrovascular accidents without CSFL, matched by age and sex, were similarly analyzed as a control group. STROBE guidelines were used in reporting results. RESULTS: All CSFL patients had IJVS (83.3% bilateral, 33.3% severe) compared to 41.7% of the control group (33.3% bilateral, 16.7% severe-occluded); p = 0.04. All CSFL patients with available venogram manometry data had at least unilateral IJV gradients. Most patients presented with modified Rankin score (mRS) of 1 (66.7%), but in those with higher mRS, medical and/or surgical interventions were associated with decreased morbidity. CONCLUSION: Spontaneous spinal CSFL was associated with IJVS in patients not meeting IIH criteria. Persistently high CSF pressure resulting in CSFL may cause opening pressure to be falsely normal or low. Internal jugular venous stenosis may be a viable target in recurrent CSFL management and improve morbidity.

The Vecta 46 intermediate catheter for mechanical thrombectomy of distal medium vessel occlusions: A single-center experience.

INTRODUCTION: With emerging evidence supporting the clinical efficacy and safety of mechanical thrombectomy (MT) for distal medium vessel occlusions (DMVOs), MT devices specifically designed to navigate through smaller caliber and more delicate tortuous distal cerebrovasculature are required. This study describes our single-center experience using the AXS Vecta 46 intermediate catheter for first-line thromboaspiration of DMVOs. METHODS: We identified all patients who underwent MT using the Vecta 46 for first-line thromboaspiration for primary or secondary DMVOs. We collected baseline clinical data, angiographic and clinical outcomes, as well as procedural complications. The primary outcome in question was the rate of successful recanalization, which was defined as a modified Thrombolysis in Cerebral Infarction score of ≥2b. RESULTS: We identified 43 patients who underwent MT using the Vecta 46 catheter for thromboaspiration of 54 DMVOs. Intervened vessels included the M2 (23/54), M3 (19/54), and M4 (6/54) branches of the middle cerebral artery, A2 (1/54), A3 (1/54), and A4 (1/54) branches of the anterior cerebral artery, and P1 (1/54), P2 (1/54), and P4 (1/54) branches of the posterior cerebral artery. The median number of passes for primary DMVOs was 2 (IQR: 1-3) and 1 (IQR: 1-1.25) for secondary DMVOs. The rate of successful recanalization was 100% (18/18) for primary DMVOs and 80.6% (29/36) for secondary DMVOs. First-pass effect (FPE) was noted in 55.6% (30/54) of all primary and secondary DMVO cases. Improved short-term clinical outcomes were observed in both the primary (National Institute of Health Stroke Scale [NIHSS] shift: -5 [IQR: -14.25 to -0.25]) and secondary (NIHSS shift: -5 [IQR: -10 to -2]) DMVO groups. A total of six patients died during their hospitalization, though none were deemed procedural-related. CONCLUSIONS: Our study demonstrates the safety and efficacy of the Vecta 46 intermediate catheter for thromboaspiration of both primary and secondary DMVOs, achieving high rates of successful recanalization and FPE.

Cerebral venous pressures, sinus trans-stenosis gradients, and intracranial pressures are dramatically augmented by head position.

BACKGROUND: Cerebral venous pressures, sinus trans-stenosis gradients, and intracranial pressures are thought to be influenced by head position. OBJECTIVE: To investigate the intracranial manifestations of these changes in patients with cerebral venous outflow disorders (CVD). METHODS: A retrospective chart review was conducted on 22 consecutive adult patients who underwent diagnostic cerebral venography with rotational internal jugular vein (IJV) venography and superior sagittal sinus (SSS) pressure measurements in multiple head positions. Data on venous sinus pressures, IJV pressures, and lumbar puncture (LP) opening pressures (OP) were collected and analyzed. RESULTS: The study found that 21 (96%) patients experienced increases in SSS pressures with head rotation, with a mean increase of 25.4%. Intracranial trans-stenosis gradients showed significant variability with head position. Additionally, LP OP measurements increased by an average of 44.3% with head rotation. Dynamic IJV stenosis was observed in all patients during rotational testing. CONCLUSION: Head position significantly affects cerebral venous pressures, trans-stenosis gradients, and intracranial pressures in patients with CVD or intracranial hypertension. These findings highlight the need for dynamic venography in the diagnostic evaluation of these conditions to better understand their pathophysiology and improve treatment strategies.

Post-acute sequelae of COVID infection and cerebral venous outflow disorders: Overlapping symptoms and mechanisms?

Neurological long Covid (NLC) is a major post-acute sequela of SARS-CoV-2 infection, affecting up to 10% of infected patients. The clinical presentation of patients with NLC is varied, but general NLC symptoms have been noted to closely mimic symptoms of cerebral venous outflow disorders (CVD). Here we review key literature and discuss evidence supporting this comparison. We also aimed to describe the similarity between CVD symptomatology and neuro-NLC symptoms from two perspectives: a Twitter-distributed survey for long covid sufferers to estimate nature and frequency of neurological symptoms, and through a small cohort of patients with long covid who underwent CVD work up per our standard workflow. Over 700 patients responded, and we argue that there is a close symptom overlap with those of CVD. CVD workup in a series of 6 patients with neurological long COVID symptoms showed jugular vein stenosis by CT venography and varying degrees of increased intracranial pressure. Finally, we discuss the potential pathogenic association between vascular inflammation, associated with COVID-19 infection, venous outflow congestion, and its potential involvement in NLC.

Idiopathic intracranial hypertension pathogenesis: The jugular hypothesis.

In spite of expanding research, idiopathic intracranial hypertension (IIH) and its spectrum conditions remain challenging to treat. The failure to develop effective treatment strategies is largely due to poor agreement on a coherent disease pathogenesis model. Herein we provide a hypothesis of a unifying model centered around the internal jugular veins (IJV) to explain the development of IIH, which contends the following: (1) the IJV are prone to both physiological and pathological compression throughout their course, including compression near C1 and the styloid process, dynamic muscular/carotid compression from C3 to C6, and lymphatic compression; (2) severe dynamic IJV stenosis with developments of large cervical gradients is common in IIH-spectrum patients and significantly impacts intracranial venous and cerebrospinal fluid (CSF) pressures; (3) pre-existing IJV stenosis may be exacerbated by infectious/inflammatory etiologies that induce retromandibular cervical lymphatic hypertrophy; (4) extra-jugular venous collaterals dilate with chronic use but are insufficient resulting in impaired aggregate cerebral venous outflow; (5) poor IJV outflow initiates, or in conjunction with other factors, contributes to intracranial venous hypertension and congestion leading to higher CSF pressures and intracranial pressure (ICP); (6) glymphatic congestion occurs but is insufficient to compensate and this pathway becomes overwhelmed; and (7) elevated intracranial CSF pressures triggers extramural venous sinus stenosis in susceptible individuals that amplifies ICP elevation producing severe clinical manifestations. Future studies must focus on establishing norms for dynamic cerebral venous outflow and IJV physiology in the absence of disease so that we may better understand and define the diseased state.

Chronic subdural hematoma: What precisely are we treating?

Subdural hematoma (SDH) refers to the collection of blood between the dura matter and the arachnoid membrane. Advancements in imaging technology have enabled the categorization of SDH based on specific imaging characteristics, causative factors, and the onset of symptoms. Given that the prognosis of SDHs varies significantly and is contingent upon the size and chronicity of the hemorrhage, a comprehensive understanding of its subtypes may carry crucial treatment implications. For example, an acute SDH classically results from severe traumatic brain injury and appears as a homogenous, crescent-shaped hyperdense extra-axial collection. If not treated, over the course of 1-3 weeks, this hematoma will evolve into a sub-acute phenotype as a consequence of subdural effusion and demonstrate mixed-density hemorrhage on imaging. Chronic SDH (cSDH) becomes the end result of an untreated SDH, with neo-membranization and neo-angiogenesis from branches of the middle meningeal artery driving a mass-like growth pattern. This review article aims to elucidate the complex anatomical features of the end-stage cSDH, with a particular focus on reconceptualization of this entity based on its mass-like growth patterns, and how this is driving a shift towards endovascular treatment.

Safety of intracranial venous stenting in patients with nickel allergy.

BACKGROUND: Nickel hypersensitivity is the most common metal related allergy. Nickel containing alloys are frequently used in endovascular devices. The use of intracranial stents in patients with nickel hypersensitivity appears to be safe, but these small series only evaluated arterial stent placement. This case series aimed to assess the safety of intracranial venous stent placement in patients with documented nickel allergy. METHODS: In this retrospective multicenter case series, patients with idiopathic intracranial hypertension and documented nickel allergy underwent treatment with a permanently implanted nickel containing stent in the dural venous sinuses. RESULTS: Nine patients with nickel allergy were included. All patients reported clinical improvement in their idiopathic intracranial hypertension symptoms. Of the five patients who had follow-up intracranial venous imaging, all stents remained patent. No patients experienced intraoperative, postoperative, or long term procedure related complications, with follow-up ranging from 1.8 weeks to 49.1 months. CONCLUSION: In this limited case series, the use of nickel containing stents in intracranial venous sinuses in patients with nickel allergy did not result in any allergic reaction or adverse outcome.

Multicenter early United States feasibility study and periprocedural safety of LVIS EVO for the treatment of unruptured intracranial aneurysms.

BACKGROUND: Stent development has focused recently on low-profile, self-expandable stents compatible with 0.0165 inch microcatheters. The LVIS EVO is the second-generation version of the Low-Profile Visualized Intraluminal Support (LVIS) with improved visibility and resheathability. The LVIS EVO underwent a limited premarket release (PMR) in December 2023. This study aims to report the early safety and feasibility experience with the LVIS EVO stent for the treatment of intracranial aneurysms in the United States (US). METHODS: This was a multicenter, retrospective, observational study evaluating patients who underwent treatment of an intracranial aneurysm with an LVIS EVO stent after the limited PMR. All physicians who had placed an LVIS EVO stent were asked to input their cases after institutional review board approval was obtained. The data were then sent to a single center for analysis. Any patient aged 18 years or older who underwent treatment of an intracranial aneurysm with a LVIS EVO stent in the US was included from the initial PMR in December 2023 until April 2024. Patient age (or ≤90 years old), sex, preoperative modified Rankin Scale (mRS), aneurysm location, aneurysm measurements, and information about preoperative antiplatelet management were all collected. Data on periprocedural complications, 30-day mortality, discharge mRS, and length of stay were also collected. RESULTS: Some 53 patients with 55 aneurysms underwent treatment with the LVIS EVO stent at 15 institutions. All aneurysms were unruptured. The most common location was the anterior communicating artery (35%) followed by the middle cerebral artery bifurcation (31%). All patients were on dual antiplatelet therapy. The average aneurysm size was 5.2 mm with a neck size of 3.7 mm. The smallest distal parent vessel size was 1.2 mm and 36% of stents were deployed in distal parent vessels <2 mm. All (100%) cases had successful deployment and the stent was repositioned in 10% of cases. A single stent was utilized in 91% of cases. Coils were placed in 48 cases (87.2%) and a microcatheter was jailed in 98% of those cases. Immediate Raymond Roy (RR) Class I occlusion was obtained in 33%, Class II in 22%, Class IIIa in 37%, and Class IIIb in 8% of cases. There were no delayed thromboembolic or hemorrhagic complications. CONCLUSIONS: The LVIS EVO is a braided, self-expanding, retrievable stent with enhanced visibility and smaller cell size. The drawn filled tube (DFT) technology results in improved visibility of the stent, allowing for more controlled stent positioning and visualization of vessel wall apposition. All cases in our series had complete neck coverage and good wall apposition. There were no thromboembolic or hemorrhagic complications.

Dynamic internal jugular vein venography: a descriptive study in 89 patients with suspected cerebral venous outflow disorders.

BACKGROUND: Internal jugular vein (IJV) stenosis has recently been recognized as a plausible source of symptom etiology in patients with cerebral venous outflow disorders (CVD). Diagnosis and determining surgical candidacy remains difficult due to a poor understanding of IJV physiology and positional symptom exacerbation often reported by these patients. METHODS: A retrospective single-center chart review was conducted on adult patients who underwent diagnostic cerebral venography with rotational IJ venography from 2022 to 2024. Patients were divided into three groups for further analysis based on symptoms and diagnostic criteria: presumed jugular stenosis, near-healthy venous outflow, and idiopathic intracranial hypertension. RESULTS: Eighty-nine patients were included in the study. Most commonly, ipsilateral rotation resulted in ipsilateral IJV stenosis and gradient development at C4-6 and contralateral stenosis and gradient appearance in the contralateral IJV at C1, with stenosis and gradient development in bilateral IJVs at C1-3 bilaterally during chin flexion. In all patients, 93.3% developed at least moderate dynamic stenosis of at least one IJV, more than two-thirds (69.7%) developed either severe or occlusive stenosis during rightward and leftward rotation, and 81.8% developed severe or occlusive stenosis with head flexion. Dynamic gradients of at least 4 mmHg were seen in 68.5% of patients, with gradients of at least 8 mmHg in 31.5% and at least 10 mmHg in 12.4%. CONCLUSION: This study is the first to document dynamic changes in IJV caliber and gradients in different head positions, offering insights into the complex nature of venous outflow and its impact on CVD.

Current and future directions in interventional neuro-oncology-are we there yet?

Advancements in technology and technical expertise increasingly enable neurointerventionalists to deliver safer and more effective endovascular treatments to cancers of the brain, spine, head, and neck. In addition to established neuro-oncological interventions such as pre-surgical tumor embolization and percutaneous ablation, newer modalities focused on direct arterial infusion of chemotherapy, radioisotopes, and radiosensitizers continue to gain traction as complementary treatment options, while stem cell-mediated delivery of theranostic nanoparticles and oncolytic virus are being explored for even greater specificity in targeting cancers across the blood-brain barrier. This article aims to provide an overview of the current state of the art and future directions for the field of interventional neuro-oncology, as well as opportunities and challenges presented by this emerging treatment modality.

The Promise, Mystery, and Perils of Stenting for Symptomatic Internal Jugular Vein Stenosis: A Case Series.

BACKGROUND AND OBJECTIVES: Cerebral venous outflow disorders (CVDs) secondary to internal jugular vein (IJV) stenosis are becoming an increasingly recognized cause of significant cognitive and functional impairment in patients. There are little published data on IJV stenting for this condition. This study aims to report on procedural success. METHODS: A single-center retrospective analysis was performed on patients with CVD that underwent IJV stenting procedures. RESULTS: From 2019 to 2023, 29 patients with CVD underwent a total of 33 IJV stenting procedures. Most patients (20; 69%) had an underlying connective tissue disorder diagnosis. The mean age of the included patients was 36.3 years (SD 12.4), 24 were female (82.8%), and all were Caucasian except for 2 patients (27; 93.0%). Twenty-eight procedures (85%) involved isolated IJV stenting under conscious sedation, whereas 5 procedures (15%) involved IJV stenting and concomitant transverse sinus stenting under general anesthesia. Thirteen (39%) patients underwent IJV stenting after open IJV decompression and styloidectomy. Three patients had stents placed for stenosis below the C1 tubercle, one of which was for carotid compression. Periprocedural complications occurred in 11 (33%), including intracardiac stent migration in 1 patient, temporary shoulder pain/weakness in 5 (15%), and persistent and severe shoulder pain/weakness in 2 patients (6%). Approximately 75% of patients demonstrated improvement after stenting although only 12 patients (36%) had durable improvement over a mean follow-up of 4.5 months (range 6 weeks-3.5 years). CONCLUSION: Our experience, along with early published studies, suggests that there is significant promise to IJV revascularization techniques in these patients; however, stenting carries a high complication rate, and symptom recurrence is common. Most neurointerventionalists should not be performing IJV stenting unless they have experience with these patients and understand technical nuances (stent sizing, anatomy, patient selection), which can maximize benefit and minimize risk.

Safety and efficacy of dynamic catheter-directed cerebral digital subtraction angiography for diagnosis of bowhunter syndrome spectrum disorders: A systematic review of the literature.

INTRODUCTION: Dynamic catheter-directed cerebral digital subtraction angiography (dcDSA) is the gold standard for diagnosing dynamic vascular occlusion syndromes such as bowhunter syndrome (BHS). Nonetheless, concerns about its safety exist and no standardized protocols have been published to date. METHODS: We describe our methodology and insights regarding the use of dcDSA in patients with BHS. We also perform a systematic literature review to identify cases of typical and atypical presentations of BHS wherein dcDSA was utilized and report on any procedural complications related to dcDSA. RESULTS: Our study included 104 cases wherein dcDSA was used for the diagnosis of BHS. There were 0 reported complications of dcDSA. DcDSA successfully established diagnosis in 102 of these cases. Thirty-eight cases were deemed atypical presentations of BHS. Fourteen patients endorsed symptoms during neck flexion/extension. In eight cases, there was dynamic occlusion of bilateral vertebral arteries during a single maneuver. Three patients had multiple areas of occlusion along a single vertebral artery (VA). An anomalous entry of the VA above the C6 transverse foramen was observed in four patients. One patient had VA occlusion with neutral head position and recanalization upon contralateral lateral head tilt. CONCLUSION: Our study highlights the safety and diagnostic benefits of dcDSA in characterizing the broad spectrum of BHS pathology encountered in clinical practice. This technique offers a powerful means to evaluate changes in cerebral blood flow and cervical arterial morphology in real time, overcoming the constraints of static imaging methods. Our findings pave the way for further studies on dcDSA to enhance cross-sectional imaging methods for the characterization of BHS and other dynamic vascular occlusion syndromes.

Endovascular vs surgical treatment of sigmoid sinus diverticulum causing pulsatile tinnitus: A systematic review.

INTRODUCTION: Sigmoid sinus diverticulum (SSD) has been increasingly reported as a cause of pulsatile tinnitus (PT). While both endovascular and surgical treatments have been used, there is a lack of consensus on the treatment modality to treat SSD. We conducted a systematic review of the available literature to compare the clinical outcomes and safety of endovascular versus surgical approaches for treating SSD. METHODS: A systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses to identify studies encompassing the management of SSD. Studies reporting the clinical outcomes and safety of endovascular or surgical treatments for SSD between January 2000 and January 2023 were included. Results were characterized using descriptive statistics. RESULTS: Endovascular treatment (EVT) was reported by 17 articles, yielding 26 patients with 27 diverticula. Surgical treatment was reported by 20 articles, yielding 105 patients with 107 diverticula. EVT led to complete or near-complete resolution in all patients with SSD and PT. Complications occurred in 3.7% (1/27) with a return to baseline after 2 months. There were no permanent complications from EVT. Surgical treatment resulted in complete resolution in 77.6% (83/107) of cases, incomplete resolution in 11.2% (12/107), and no resolution in 11.2% (12/107). Significant complications occurred in 9.3% (10/107) of the surgical-treated patients. CONCLUSION: EVT in patients with PT and venous diverticulum appears more effective and safer than surgical treatment, but large studies are lacking. Studies directly comparing endovascular and surgical treatment are needed.

Superior cortical venous anatomy for endovascular device implantation: a systematic review.

Endovascular electrode arrays provide a minimally invasive approach to access intracranial structures for neural recording and stimulation. These arrays are currently used as brain-computer interfaces (BCIs) and are deployed within the superior sagittal sinus (SSS), although cortical vein implantation could improve the quality and quantity of recorded signals. However, the anatomy of the superior cortical veins is heterogenous and poorly characterised. MEDLINE and Embase databases were systematically searched from inception to December 15, 2023 for studies describing the anatomy of the superior cortical veins. A total of 28 studies were included: 19 cross-sectional imaging studies, six cadaveric studies, one intraoperative anatomical study and one review. There was substantial variability in cortical vein diameter, length, confluence angle, and location relative to the underlying cortex. The mean number of SSS branches ranged from 11 to 45. The vein of Trolard was most often reported as the largest superior cortical vein, with a mean diameter ranging from 2.1 mm to 3.3 mm. The mean vein of Trolard was identified posterior to the central sulcus. One study found a significant age-related variability in cortical vein diameter and another identified myoendothelial sphincters at the base of the cortical veins. Cortical vein anatomical data are limited and inconsistent. The vein of Trolard is the largest tributary vein of the SSS; however, its relation to the underlying cortex is variable. Variability in cortical vein anatomy may necessitate individualized pre-procedural planning of training and neural decoding in endovascular BCI. Future focus on the relation to the underlying cortex, sulcal vessels, and vessel wall anatomy is required.

Scalpellum occulta: A rare case of dorsal spinal arachnoid web without the scalpel sign.

Spinal arachnoid web is a rare condition characterized by extramedullary bands of arachnoid tissue at the level of the dorsal thoracic spinal cord that may lead to progressive, permanent neurological deficits. To date, this condition has been radiographically characterized by a scalpel sign, which has been pathognomonic in all reported cases of spinal arachnoid webs. In this case, we report the first known patient with confirmed spinal arachnoid web without radiographic evidence of the scalpel sign. In reporting our finding, we encourage a higher clinical suspicion for spinal arachnoid web in patients presenting with progressive thoracic myelopathy following trauma, and radiographic evidence of ventrally displaced spinal cord and turbulent cerebrospinal fluid flow, even in the absence of a scalpel sign.

Differential Assessment of Internal Jugular Vein Stenosis in Patients Undergoing CT and MRI with Contrast.

OBJECTIVE: Internal Jugular Vein Stenosis (IJVS) is hypothesized to play a role in the pathogenesis of diverse neurological diseases. We sought to evaluate differences in IJVS assessment between CT and MRI in a retrospective patient cohort. METHODS: We included consecutive patients who had both MRI of the brain and CT of the head and neck with contrast from 1 June 2021 to 30 June 2022 within the same admission. The degree of IJVS was categorized into five grades (0-IV). RESULTS: A total of 35 patients with a total of 70 internal jugular (IJ) veins were included in our analysis. There was fair intermodality agreement in stenosis grades (κ = 0.220, 95% C.I. = [0.029, 0.410]), though categorical stenosis grades were significantly discordant between imaging modalities, with higher grades more frequent in MRI (χ2 = 27.378, p = 0.002). On CT-based imaging, Grade III or IV stenoses were noted in 17/70 (24.2%) IJs, whereas on MRI-based imaging, Grade III or IV stenoses were found in 40/70 (57.1%) IJs. Among veins with Grade I-IV IJVS, MRI stenosis estimates were significantly higher than CT stenosis estimates (77.0%, 95% C.I. [35.9-55.2%] vs. 45.6%, 95% C.I. [35.9-55.2%], p < 0.001). CONCLUSION: MRI with contrast overestimates the degree of IJVS compared to CT with contrast. Consideration of this discrepancy should be considered in diagnosis and treatment planning in patients with potential IJVS-related symptoms.

Direct superficial temporal artery access for middle meningeal artery embolization.

Middle meningeal artery embolization has become an important option in the management of subdural hemorrhages with multiple prospective studies demonstrating efficacy and randomized controlled trial data on the way. Access to the middle meningeal artery is usually achieved via the external carotid artery to the internal maxillary artery, then the middle meningeal artery. We report a case where a patient with symptomatic left-sided chronic subdural hemorrhage also had an external carotid artery occlusion. Direct puncture of the superficial temporal artery allowed retrograde access to the internal maxillary artery and thus the middle meningeal artery. Successful embolization of the vessel with 1:9 nBCA was performed with near total resorption of the subdural collection by 1 month postprocedure.

Hypothermia is Associated with Improved Neurological Outcomes After Mechanical Thrombectomy.

BACKGROUND: Acute ischemic stroke (AIS) is the second leading cause of death globally. Mechanical thrombectomy (MT) has improved patient prognosis but expedient treatment is still necessary to minimize anoxic injury. Lower intraoperative body temperature decreases cerebral oxygen demand, but the role of hypothermia in treatment of AIS with MT is unclear. METHODS: We retrospectively reviewed patients undergoing MT for AIS from 2014 to 2020 at our institution. Patient demographics, comorbidities, intraoperative parameters, and outcomes were collected. Maximum body temperature was extracted from minute-by-minute anesthesia readings, and patients with maximal temperature below 36°C were considered hypothermic. Risk factors were assessed by χ2 and multivariate ordinal regression. RESULTS: Of 68 patients, 27 (40%) were hypothermic. There was no significant association of hypothermia with patient age, comorbidities, time since last known well, number of passes intraoperatively, favorable revascularization, tissue plasminogen activator use, and immediate postoperative complications. Hypothermic patients exhibited better neurologic outcome at 3-month follow-up (P = 0.02). On multivariate ordinal regression, lower maximum intraoperative body temperature was associated with improved 3-month outcomes (P < 0.001), when adjusting for other factors influencing neurological outcomes. Other significant protective factors included younger age (P = 0.03), better revascularization (P = 0.03), and conscious sedation (P = 0.02). CONCLUSIONS: Lower intraoperative body temperature during MT was independently associated with improved neurological outcome in this single center retrospective series. These results may help guide clinicians in employing therapeutic hypothermia during MT to improve long-term neurologic outcomes from AIS, although larger studies are needed.