Artery M1 Research Articles

Treatment of Cerebral Vasospasm after Aneurysmal Subarachnoid Hemorrhage Using the Compliant Manually Adjustable Mesh Comaneci.

Background and purpose: Cerebral vasospasm (CV) following aneurysmal subarachnoid hemorrhage (aSAH) may lead to morbidity and mortality. Endovascular mechanical angioplasty may be performed if symptomatic CV is refractory to noninvasive medical management. Compliant and noncompliant balloons and manually adjustable mesh may be used in this indication. We describe our initial experience with the Comaneci (Rapid Medical, Yokneam, Israel) in cerebral vasospasm treatment following aSAH. Methods: All patients included in the prospective observational SAVEBRAIN PWI (NCT05276934 on clinicaltrial.gov) study who underwent cerebral angioplasty using the Comaneci device for the treatment of medically refractory and symptomatic CV after aSAH were identified. Patient demographic information, procedural details, and outcomes were obtained from electronic medical records. Results: Between February 2022 and June 2023, seven consecutive patients underwent CV treatment with the Comaneci. Angioplasty of 37 arterial segments (supraclinoid internal carotid artery, A1, A2, and A3 segments of the anterior cerebral artery and M1 and M2 segments of the middle cerebral artery) was attempted, and 35/37 (95%) were performed. The vessel diameter improved significantly following angioplasty (+64%), while brain hypoperfusion decreased (-45% of the mean T Max). There was no long-term clinical complication, and 6% per-procedural complications occurred. Conclusions: The Comaneci is effective in the treatment of cerebral vasospasm following aSAH, bringing a new device in the armamentarium of the neurointerventionalist to perform intracranial angioplasty.

Predictive value of follow-up infarct volume on functional outcomes in middle cerebral artery M2 segment vessel occlusion stroke treated with mechanical thrombectomy.

Medium vessel occlusion (MeVO) strokes, particularly affecting the M2 segment of the middle cerebral artery, represent a critical proportion of acute ischemic strokes, posing significant challenges in management and outcome prediction. The efficacy of mechanical thrombectomy (MT) in MeVO stroke may warrant reliable predictors of functional outcomes. This study aimed to investigate the prognostic value of follow-up infarct volume (FIV) for predicting 90-day functional outcomes in MeVO stroke patients undergoing MT. This multicenter, retrospective cohort study analyzed data from the Multicenter Analysis of primary Distal medium vessel occlusions: effect of Mechanical Thrombectomy (MAD-MT) registry, covering patients with acute ischemic stroke due to M2 segment occlusion treated with MT. We examined the relationship between 90-day functional outcomes, measured by the modified Rankin Scale (mRS), and follow-up infarct volume (FIV), assessed through CT or MRI within 12-36 h post-MT. Among 130 participants, specific FIV thresholds were identified with high specificity and sensitivity for predicting outcomes. A FIV ⩽5 ml was highly specific for predicting favorable and excellent outcomes. The optimal cut-off for both prognostications was identified at ⩽15 ml by the Youden Index, with significant reductions in the likelihood of favorable outcomes observed above a 40 ml threshold. Receiver Operator Curve (ROC) analyses confirmed FIV as a superior predictor of functional outcomes compared to traditional recanalization scores, such as final modified thrombolysis in cerebral infarction score (mTICI). Multivariable analysis further highlighted the inverse relationship between FIV and positive functional outcomes. FIV within 36 h post-MT serves as a potent predictor of 90-day functional outcomes in patients with M2 segment MeVO strokes. Establishing FIV thresholds may aid in the prognostication of stroke outcomes, suggesting a role for FIV in guiding post intervention treatment decisions and informing clinical practice. Future research should focus on validating these findings across diverse patient populations and exploring the integration of FIV measurements with other clinical and imaging markers to enhance outcome prediction accuracy.

Clinical and radiographic outcomes after mechanical thrombectomy in medium-vessel posterior cerebral artery occlusions: Subgroup analysis from STAR.

Whereas mechanical thrombectomy (MT) has become standard-of-care treatment for patients with salvageable brain tissue after acute stroke caused by large-vessel occlusions, the results of MT in patients with medium-vessel occlusions (MEVOs), particularly in the posterior cerebral artery (PCA), are not well known. Using data from the international Stroke Thrombectomy and Aneurysm Registry (STAR), we assessed presenting characteristics and clinical outcomes for patients who underwent MT for primary occlusions in the P2 PCA segment. As a subanalysis, we compared the PCA MeVO outcomes with STAR's anterior circulation MeVO outcomes, namely middle cerebral artery (MCA) M2 and M3 segments. Of the 9812 patients in STAR, 43 underwent MT for isolated PCA MeVOs. The patients' median age was 69 years (interquartile range 61-79), and 48.8% were female. The median NIH Stroke Scale score was 9 (range 6-17). After recanalization, 67.4% of patients achieved successful recanalization (modified treatment in cerebral infarction score [mTICI] ≥ 2b), with a first-pass success rate of 44.2%, and 39.6% achieved a modified Rankin score of 0-2 at 90 days. Nine patients (20.9%) had died by the 90-day follow-up. In comparison with M2 and M3 MeVOs, there were no differences in presenting characteristics among the three groups. Patients with PCA MeVOs were less likely to undergo intra-arterial thrombolysis (4.7% PCA vs. 10.1% M2 vs. 16.2% M3, p = 0.046) or to achieve successful recanalization (mTICI ≥ 2b, 67.4%, 86.7%, 82.3%, respectively, p < 0.001); however, there were no differences in the rates of successful first-pass recanalization (44.2%, 49.8%, 52.3%, respectively, p = 0.65). We describe the STAR experience performing MT in patients with PCA MeVOs. Our analysis supports that successful first-pass recanalization can be achieved in PCA MEVOs at a rate similar to that in MCA MeVOs, although further study and possible innovation may be necessary to improve successful PCA MeVO recanalization rates.

Validation of a model for outcome prediction after endovascular treatment for ischemic stroke.

The recently developed MR-PREDICTS@24 h model showed excellent performance in the MR-CLEAN Registry cohort in patients presenting within 12 h from onset. However, its applicability to an U.S. population and to patients presenting beyond 12 h from last known normal are still undetermined. We aim to externally validate the MR-PREDICTS@24 h model in a new geographic setting and in the late window. In this retrospective analysis of a prospectively collected database from a comprehensive stroke center in the United States, we included patients with intracranial carotid artery or middle cerebral artery M1 or M2 segment occlusions who underwent endovascular therapy and applied the MR-PREDICTS@24 h formula to estimate the probabilities of functional outcome at day 90. The primary endpoint was the modified Rankin Scale (mRS) at 90 days. We included 1246 patients, 879 in the early (<12 h) and 367 in the late (≥12 h) cohort. For both cohorts, calibration and discrimination of the model were accurate throughout mRS levels, with absolute differences between estimated and predicted proportions ranging from 1% to 5%. Calibration metrics and curve inspections showed good performance for estimating the probabilities of mRS ≤ 1 to mRS ≤ 5 for the early cohort. For the late cohort, predictions were reliable for the probabilities of mRS ≤ 1 to mRS ≤ 4. The MR-PREDICTS@24 h was transferrable to a real-world U.S.-based cohort in the early window and showed consistently accurate predictions for patients presenting in the late window without need for updating.

Comparative Analysis of Mechanical Thrombectomy Outcomes of Middle Cerebral Artery M1, M2 Superior, and M2 Inferior Occlusion Strokes

BackgroundThe M1 middle cerebral artery (MCA) commonly bifurcates into an M2 superior and an M2 inferior segment. However, MCA anatomy is highly variable rendering classification for mechanical thrombectomy (MT) trials difficult. Safety and effectiveness of M2 MCA stroke thrombectomy stratified by M2 MCA anatomy remains to be explored. MethodsLarge vessel occlusion strokes undergoing MT between 02/2016-08/2022 were reviewed (n=784). M1 (n=431) and M2 MCA (n=118) occlusions were assessed. Among M2 MCA occlusions only prototypical MCA bifurcation anatomy cases were included (n=99). Dominance was assessed based on angiography. Procedural and outcome data was compared between M1, M2 superior and M2 inferior MCA occlusions. ResultsBaseline demographics and periprocedural criteria of M2 superior (n=56) and M2 inferior (n=43) occlusion MTs were comparable. Among M2 inferior cases, the occluded branch was dominant in 41/43 (95.3%) but only in 37/56 (66.1%) among M2 superior cases (p<0.001). The 90-day favorable functional outcome (mRS 0-2) and mortality (mRS 6) rates were 60.0% and 8.9% in the M2 superior, 42.9% and 32.6% in the M2 inferior, and 44.1% and 26.0% in the M1 group (n=431). Compared to M2 superior, M2 inferior favorable outcome rates were lower (p=0.094) and mortality rates were higher (p=0.003) and resembled M1 outcome rates (p=0.750 and p=0.355, respectively). ConclusionIn setting of prototypical MCA bifurcation anatomy, thrombectomy of dominant M2 inferior occlusions had outcome rates like M1 occlusions. In contrast, M2 superior occlusions had significantly lower mortality rates and a trend towards better favorable functional outcome rates.

Comparing Outcomes of Thrombectomy Versus Intravenous Thrombolysis Based on Middle Cerebral Artery M2 Occlusion Features.

Current evidence provides limited support for the superiority of endovascular thrombectomy (EVT) in patients with M2 segment middle cerebral artery occlusion. We aim to investigate whether imaging features of M2 segment occlusion impact the effectiveness of EVT. We conducted a retrospective cohort study from January 2017 to January 2022, drawing data from the CASE II registry (Computer-Based Online Database of Acute Stroke Patients for Stroke Management Quality Evaluation), which specifically documented patients with acute ischemic stroke presenting with M2 segment occlusion undergoing reperfusion therapy. Patients were stratified into the intravenous thrombolysis (IVT) group (IVT alone) and EVT group (IVT plus EVT or EVT alone). The primary outcome was a modified Rankin Scale score 0 to 2 at 90 days. Secondary outcomes included additional thresholds and distribution of modified Rankin Scale scores, 24-hour recanalization, early neurological deterioration, and relevant complications during hospitalization. Safety outcomes encompassed intracranial hemorrhagic events at 24 hours and mortality at 90 days. Binary logistic regression analyses with propensity score matching were used. Subgroup analyses were performed based on the anatomic site of occlusion, including right versus left, proximal versus distal, dominant/co-dominant versus nondominant, single versus double/triple branch(es), and anterior versus central/posterior branch. Among 734 patients (43.3% were females; median age, 73 years) with M2 segment occlusion, 342 (46.6%) were in the EVT group. Propensity score matching analysis revealed no statistical difference in the primary outcome (odds ratio, 0.860 [95% CI, 0.611-1.209]; P=0.385) between the EVT group and IVT group. However, EVT was associated with a higher incidence of subarachnoid hemorrhage (odds ratio, 6.655 [95% CI, 1.487-29.788]; P=0.004) and pneumonia (odds ratio, 2.015 [95% CI, 1.364-2.977]; P<0.001). Subgroup analyses indicated that patients in the IVT group achieved better outcomes when presenting with right, distal, or nondominant branch occlusion (Pall interaction<0.05). Our study showed similar efficiency of EVT versus IVT alone in acute M2 segment middle cerebral artery occlusion. This suggested that only specific patient subpopulations might have a potentially higher benefit of EVT over IVT alone. URL: https://clinicaltrials.gov; Unique identifier: NCT04487340.

Intracranial thrombus composition is associated with occlusion location and endovascular treatment outcomes: results from ITACAT multicenter study

BackgroundThe impact of thrombolytics directed towards different thrombus components regarding site of occlusion in combination with mechanical thrombectomy (MT) to achieve endovascular complete recanalization is unclear.MethodsRetrospective analysis of a prospective...

Vascular syndrome predicts the development and course of epilepsy after perinatal stroke.

Epilepsy develops in one third of the patients after perinatal stroke. It is still unclear which vascular syndrome of ischemic stroke carries higher risk of epilepsy. The aim of the current study was to evaluate the risk of epilepsy according to the vascular syndrome of perinatal stroke. The study included 39 children with perinatal arterial ischemic stroke (13 with anterior or posterior trunk of the distal middle cerebral artery occlusion, 23 with proximal or distal M1 middle cerebral artery occlusion and three with lenticulostriate arteria infarction), and 44 children with presumed perinatal venous infarction. Magnetic resonance imaging obtained at the chronic stage was used to evaluate the vascular syndrome of stroke. The median follow-up time was 15.1 years (95% CI: 12.4-16.5 years), epilepsy developed in 19/83 (22.9%) patients. The cumulative probability to be without epilepsy at 15 years was 75.4% (95% CI: 65.8-86.4). The probability of having epilepsy was higher in the group of proximal or distal M1 artery occlusion compared to patients with periventricular venous infarction (HR 7.2, 95% CI: 2.5-26, p = .0007). Patients with periventricular venous infarction had significantly more often status epilepticus or spike-wave activation in sleep ≥85% of it compared to patients with anterior or posterior trunk of the distal middle cerebral artery occlusion (OR = 81; 95% CI: 1.3-5046, p = .029). The emphasis of this study is placed on classifying the vascular syndrome of perinatal stroke and on the targeted follow-up of patients for epilepsy until young adulthood. The risk for having epilepsy after perinatal stroke is the highest in children with proximal or distal M1 middle cerebral artery occlusion. Patients with periventricular venous infarction have a more severe course of epilepsy.

Endovascular Therapy and Outcomes Among Patients With Very Large Ischemic Core Stroke

The association of endovascular therapy (EVT) with outcomes is unclear for patients with very low Alberta Stroke Program Early Computed Tomography Score (ASPECTS) within 24 hours of stroke onset. To explore the association of EVT with functional and safety outcomes among patients with ASPECTS of 0 to 2 scored with noncontrast computed tomography. This cohort study used data from an ongoing, prospective, observational, nationwide registry including all patients treated at 38 stroke centers in China with an occlusion in the internal carotid artery or M1 or M2 segment of the middle cerebral artery within 24 hours of witnessed symptom onset. Patients with ASPECTS of 0 to 2 between November 1, 2021, and February 8, 2023, were included in analysis. Data were analyzed October to November 2023. EVT vs standard medical treatment (SMT). The primary outcome was favorable functional outcome, defined as modified Rankin Scale score (mRS) of 0 to 3, at 90 days. Safety outcomes included symptomatic intracerebral hemorrhage (sICH) within 48 hours and mortality at 90 days. A total of 245 patients (median [IQR] age, 71 [63-78] years; 118 [48%] women) with ASPECTS of 0 to 2 were included, of whom 111 patients (45.1%) received SMT and 135 patients (54.9%) received EVT. The EVT group had significantly greater odds of favorable functional outcome at 90 days than the SMT group (30 patients [22.2%] vs 11 patients [9.9%]; P = .01; adjusted odds ratio [aOR], 3.07 [95% CI, 1.29-7.31]; P = .01). Patients in the EVT group, compared with the SMT group, had significantly greater odds of any ICH (56 patients [41.5%] vs 16 patients [11.4%]; P < .001; aOR, 4.27 [95% CI, 2.19-8.35]; P < .001) and sICH (24 patients [17.8%] vs 1 patient [0.9%]; P < .001; aOR, 23.07 [95% CI, 2.99-177.79]; P = .003) within 48 hours. There were no differences between groups for 90-day mortality (80 patients [59.3%] vs 59 patients [53.2%]; P = .34; aOR, 1.38 [95% CI, 0.77-2.47]; P = .28). The results remained robust in the propensity score-matched analysis. In this cohort study of patients with very low ASPECTS based on NCCT within 24 hours of stroke onset, those treated with EVT had higher odds of a favorable functional outcome compared with those who received SMT. Randomized clinical trials are needed to assess these findings.

Mechanical thrombectomy for middle cerebral artery M2 occlusions.

The safety and efficacy of mechanical thrombectomy (MT) for proximal large vessel occlusion after acute ischemic stroke (AIS) have been demonstrated. Clinical investigations of endovascular approaches for treating AIS due to M2 occlusions have been ongoing. To assess the outcomes of M2 occlusions according to treatment modality and anatomical division. A total of 113 consecutive M2 occlusions treated with endovascular treatment (EVT) at our tertiary stroke center between January 2019 and December 2022 were retrospectively analyzed. Patients were divided into three groups: mechanical thrombectomy (MT); intravenous thrombolysis plus MT (IVT + MT); and IVT alone. The primary outcomes were good prognosis (mRS = 0-2) and mortality (mRS = 6) on day 90. The secondary outcome was to determine the differences in outcomes between lesions in the superior and inferior branches of M2. In total, 55 (48.7%) patients underwent MT. In 42 (37.2%) patients, bridging IVT was performed with MT, and IVT alone was applied in 16 (14.2%) patients. Neither the prognosis at 90 days nor the mortality rate significantly differed among the groups. The outcomes did not significantly differ between occlusions in the superior and inferior branches of M2. MT was found to be safe and effective for treating M2 occlusions in this series.

Abstract TP214: In-Silico versus In-Vitro Evaluation of a New Stent-Retriever Design: A Novel Approach to Pre-Clinical Device Development

Introduction: In-vitro evaluation (analysis in a bench top flow model) is the gold standard for pre-clinical investigation of devices being developed for endovascular thrombectomy (EVT). In-silico evaluation (computer simulated analysis in a virtual stroke model) has the potential to test and optimize large number of stent-retriever design variations in a relatively time and cost-effective manner. We aim to validate the utility of in-silico evaluation when compared with in-vitro evaluation for the SuperNova Stent-retriever. Methods: In-silico analysis was performed using a virtual thrombectomy model, built using data from a fine-grained finite-element model, to estimate the probability of successful recanalization. Neurovascular anatomy of the virtual model was built based on digital subtraction angiography of an in-vitro model (Sim Agility, Mentice, Inc). Gravity Medical Technology’s SuperNova Stent-retriever was the device under investigation. Multiple thrombectomy scenarios were defined and validation analysis was performed. Results: We defined multiple thrombectomy scenarios including 1 cm red blood clot in M1 artery, 2 cm bifurcation M1-M2 red blood clot (Y-shaped clot), 1 cm white blood clot in M1 artery, and 1 cm white blood clot in superior M2 artery. The figure below demonstrates a pictorial representation of the first scenario- 1 cm red blood clot in M1 artery followed by mechanical thrombectomy simulation using the SuperNova stent-retriever. Per our in-vitro analysis (10 thrombectomy experiments), the rate of first pass effect and the rate of complete recanalization after a maximum of 3 passes using SuperNova stent-retriever was 50% and 90%, respectively. Preliminary data suggests 97% concordance. Conclusion: In-silico analysis has the potential to improve and expedite pre-clinical thrombectomy device development. Further studies are required to better understand the scope and potential of this technology.

A case of contact aspiration with microcatheter for occlusion of a distal middle cerebral artery M2: a case report

A case of contact aspiration with microcatheter for occlusion of a distal middle cerebral artery M2: a case report

Clinical Results of Mechanical Thrombectomy in Middle Cerebral Artery M2 Segment Compared to M1 Segment: A Single-Stroke Center Cohort Study

Clinical Results of Mechanical Thrombectomy in Middle Cerebral Artery M2 Segment Compared to M1 Segment: A Single-Stroke Center Cohort Study

Safety and Efficacy of Aspiration Catheter CAT6 and 5 Fr Navien in the Endovascular Treatment of Acute Ischemic Stroke.

Mechanical thrombectomy has become a key treatment option for acute ischemic stroke. This study compared the safety and efficacy of aspiration catheter CAT6 and 5 Fr Navien. Thrombectomy was performed in103 patients with the acute internal carotid artery, middle cerebral artery M1 or M2 occlusions, including the CAT6 group (n=53 with stent retriever and CAT6 aspiration) and the 5 Fr Navien group (n=50 with stent retriever and 5 Fr Navien aspiration) at the Advanced Stroke Center. Overall, an aspiration catheter placement success rate was achieved in 93.2% of cases, 52 (98.11%) for CAT6, and 44 (88.00%) for 5 Fr Navien ( P =0.042). Overall, 17 cases (16.51%) required additional guidewire rates, 5.66% for CAT6, and 13.592% for 5 Fr Navien ( P =0.002). First-pass success rate (FPSR) was achieved in 38.84% of cases overall, a rate that did not differ significantly between catheters: 45.28% for CAT6; 32.00% for 5 Fr Navien ( P =0.167). Final thrombolysis in cerebral infarction 2b or 3 reperfusion was achieved in 91.26% of cases overall, 51 (96.23%) for CAT6, and 43 (86%) for 5 Fr Navien ( P =0.066). The participants had a mean number of passes for the index thrombus of 1.956 and a median procedure time of 65.82±21.8 minutes. There was no significant difference found in 90-day good outcome (mean 42.7%, modified Rankin Score 0 to 2) and 90-day mortality (17%) between CAT6 and 5 Fr Navien. Aspiration catheter placement success rate and first-pass success rate seemed to be higher for CAT6 and, moreover, the rate of additional guidewires was lower.

Operative Strategies for Aplastic Circle of Willis Arteries on CTA in Meningioma Surgery: A Case Report

BACKGROUND AND IMPORTANCE: Meningiomas frequently involve critical neurovascular structures. Preoperative imaging with computed tomography angiography (CTA) can help understand the relationship of tumor with neurovascular structures. Although CTA was useful in preoperative planning and less invasive, we present a unique case in which it mistakenly represents a hypoplastic anterior cerebral artery as aplastic and thus displays poor sensitivity in the Circle of Willis. CLINICAL PRESENTATION: A 66-year-old woman presented with new onset seizures and MRI demonstrated a sphenoid wing meningioma with tumor involvement of the internal carotid artery and right M1 artery. On preoperative CTA, a right A1 artery was not appreciated. However, a hypoplastic right A1 artery was identified during careful dissection guided by micro-Doppler and found to be encased within the tumor. All arteries were preserved, and a near-total resection was achieved with a small remnant of tumor at the supraclinoid internal carotid artery. CONCLUSION: Although CTAs can be useful in understanding vascular anatomy and its association with tumors, they are not ideal for providing information about hypoplastic arterial segments. Seemingly aplastic arteries on CTA may very well be present, albeit hypoplastic. While we recognize the usefulness of a less invasive modality of CTA to help guide surgical strategy, we underscore recognizing this potential pitfall and recommend the use of the microvascular Doppler during careful dissection when working within tumor in the location of a seemingly aplastic artery.

Abstract 249: In‐silico Versus In‐Vitro Evaluation of a New Stent‐Retriever Design: A Novel Approach to Pre‐clinical Development

Introduction In‐vitro evaluation (analysis in a bench top flow model) is the gold standard and a regulatory requirement for pre‐clinical investigation of devices being developed for endovascular thrombectomy (EVT). In‐silico evaluation (computer simulated analysis in a virtual stroke model) has the potential to test and optimize large number of stent‐retriever design variations in a relatively time and cost‐effective manner. Further, new design concepts can be tested across multiple anatomical scenarios. We aim to validate the utility of in‐silico evaluation when compared with in‐vitro evaluation for the SuperNova Stent‐retriever. Methods In‐silico analysis was performed using a virtual thrombectomy model, built using data from a fine‐grained finite‐element model, to estimate the probability of successful recanalization and emboli in new/distal territory. Neurovascular anatomy of the virtual model was built based on digital subtraction angiography of an in‐vitro model (Sim Agility, Mentice, Inc). Gravity Medical Technology’s SuperNova Stent‐retriever was the device under investigation‐ physical device for in‐vitro analysis and virtual replica for in‐silico analysis (built using finite element analysis incorporating various physical metrics of the stent‐retriever). Experiments performed for in‐vitro analysis were replicated for in‐silico analysis. Multiple thrombectomy scenarios were defined and validation analysis was performed. Data was analyzed using SPSS 23 (IBM, Armonk, NY) Results We defined multiple thrombectomy scenarios including 1 cm red blood clot in M1 artery, 2 cm bifurcation M1‐M2 red blood clot (Y‐shaped clot), 1 cm white blood clot in M1 artery, and 1 cm white blood clot in superior M2 artery. The figure below demonstrates a pictorial representation of the first scenario‐ 1 cm red blood clot in M1 artery followed by mechanical thrombectomy simulation using the SuperNova stent‐retriever. Per our in‐vitro analysis (10 thrombectomy experiments), the rate of first pass effect and the rate of complete recanalization after a maximum of 3 passes using SuperNova stent‐retriever was 50% and 90%, respectively. Complete data from in‐silico analysis is being generated and will be presented at the conference. Preliminary data suggests high degree of concordance. Conclusion In‐silico analysis has the potential to improve and expedite pre‐clinical thrombectomy device development. Further studies are required to better understand the scope and potential of this technology.

Common carotid artery dissection from sportive choking

Tandem occlusions of the anterior circulation refer to the simultaneous presence of a cervical carotid artery occlusion or high-grade stenosis and an ipsilateral large vessel occlusion involving the intracranial internal carotid artery, M1 or proximal M2 middle cerebral artery. Whilst carotid occlusion usually results from progressive atherosclerotic disease, in younger individuals it may arise secondary to a dissection for which there are multiple aetiologies, with trauma being an important cause in patients having a relevant history. We present a rare case of traumatic left common carotid artery dissection in a young professional Jiu-Jitsu fighter presenting with delayed stroke symptoms and angiographic findings of a tandem occlusion. This case was successfully managed with endovascular clot retrieval and antiplatelet medication.

Transorbital Microsurgery: An Anatomical Description of a Minimally Invasive Corridor to the Anterior Cranial Fossa and Paramedian Structures.

Objectives Transorbital neuroendoscopic surgery (TONES) has ignited interest in the transorbital access corridor, increasing its use for single and multi-portal skull base interventions. However, the crowding of a small corridor and two-dimensional viewing restrict this access portal. Design Cadaveric qualitative study to assess the feasibility of transorbital microsurgery (TMS). Setting Anatomical dissection steps and instrumentation were recorded for homogeneous methodology. Participants Six cadaveric specimens were systematically dissected using TMS to the anterior cranial fossa and paramedian structures. Main Outcome Measures Anatomical parameters of the TMS craniectomy were established, and the visible and accessible neuroanatomy was highlighted. Results A superior lid crease incision achieved essential orbital rim exposure and preseptal dissection. The orbital roof craniectomy is defined by three boundaries: (1) frontozygomatic suture to the frontosphenoid suture, (2) frontal sinus and cribriform plate, and (3) frontal sinus and orbital rim. The mean (standard deviation) craniectomy was 440 mm 2 (78 mm 2 ). Exposing the ipsilateral optic nerve and internal carotid artery obviated the need for frontal lobe retraction to identify the A1-M1 bifurcation as well as near-complete visualization of the M1 artery. Conclusion TMS is a feasible corridor for intracranial access. Mobilization of orbital contents is imperative for maximal intracranial access and protection of the globe. TMS enables access to the frontal lobe base, ipsilateral optic nerve, and most of the ipsilateral anterior circulation. This cosmetically satisfactory approach causes minimal destruction of the anterior skull base with satisfactory exposure of the anterior cranial fossa floor without sinus invasion.

Impact on collateral flow of devices used for endovascular treatment of stroke: an in-vitro flow model

BackgroundCollateral blood supply of distal vessels has been linked to clinical outcome, infarct volume and recanalization rates in patients with large vessel occlusion. Our study aimed to explore the effects...

The incidence of medium vessel occlusions: a population-based study.

The incidence of medium vessel occlusion (MeVO) is not well known. The objective of our study is to perform a population-based assessment to estimate the incidence of MeVOs. Consecutive patients from Olmsted County, Minnesota who presented for acute ischemic stroke seen at Mayo Clinic Hospital from 1/1/2018 to 12/31/2020 who were found to have a MeVO were included in this study. MeVO was defined as occlusion at or beyond the level of the middle cerebral artery M2 segment, anterior cerebral artery A2 segment, posterior cerebral artery P1 segment, and cerebellar arteries. Census data for Olmsted County was obtained from the United States Census Bureau from the year 2020. A total of 1,718 patients were screened for the study, 77 patients fulfilled inclusion criteria to be included in the study. Presenting NIHSS was 9 (± 7). The population of Olmsted County was estimated to be 162,847. The incidence rate for MeVO was 16 cases (95% CI 12-19) per 100,000 people per year. Based on estimates of the US population in 2020 of 331,449,281 people, we estimate there are 52,236 (95% CI 40,635-64,002) new cases of MeVOs per year. As the only stroke center in Olmsted County, we have been able to estimate the incidence of ischemic stroke due to MeVO. While the incidence of MeVOs is less than both large and small vessel occlusions, they still represent a significant proportion of strokes with significant morbidity and mortality that would benefit from further studies in both acute intervention and prevention.