A deep learning method to identify and localize large-vessel occlusions from cerebral digital subtraction angiography.

BACKGROUND AND PURPOSE: An essential step during endovascular thrombectomy is identifying the occluded arterial vessel on a cerebral digital subtraction angiogram (DSA). We developed an algorithm that can detect and localize the position of occlusions in cerebral DSA. METHODS: We retrospectively collected cerebral DSAs from a single institution between 2018 and 2020 from 188 patients, 86 of whom suffered occlusions of the M1 and proximal M2 segments. We trained an ensemble of deep-learning models on fewer than 60 large-vessel occlusion (LVO)-positive patients. We evaluated the model on an independent test set and evaluated the truth of its predicted localizations using Intersection over Union and expert review. RESULTS: On an independent test set of 166 cerebral DSA frames with an LVO prevalence of 0.19, the model achieved a specificity of 0.95 (95% confidence interval [CI]: 0.90, 0.99), a precision of 0.7450 (95% CI: 0.64, 0.88), and a sensitivity of 0.76 (95% CI: 0.66, 0.91). The model correctly localized the LVO in at least one frame in 13 of the 14 LVO-positive patients in the test set. The model achieved a precision of 0.67 (95% CI: 0.52, 0.79), recall of 0.69 (95% CI: 0.46, 0.81), and a mean average precision of 0.75 (95% CI: 0.56, 0.91). CONCLUSION: This work demonstrates that a deep learning strategy using a limited dataset can generate effective representations used to identify LVOs. Generating an expanded and more complete dataset of LVOs with obstructed LVOs is likely the best way to improve the model's ability to localize LVOs.

Use of angled-tip aspiration catheters is associated with a lower cost of thrombectomy in patients with acute ischemic stroke secondary to large and medium vessel occlusions.

BACKGROUND: Recently, the angled-tip Zoom™ aspiration catheters were introduced. The tip is designed to improve suction force for clot retrieval. We evaluated the possibility of reducing procedure costs when using angled-tip catheters and compared the safety and angiographic effectiveness of angled-tip versus straight-tip catheters. METHODS: We conducted a retrospective single-center cohort study involving patients with acute ischemic stroke due to large and medium vessel occlusions. The patients were divided into two groups: the post-Zoom group, in which angled-tip aspiration catheters were used and the pre-Zoom group, in which traditional straight-tip catheters were employed. RESULTS: A total of 163 patients were included; 95 (58.3%) in the pre-Zoom group and 68 (41.7%) in the post-Zoom group. The groups were well-matched at entry. The post-Zoom group demonstrated a significant decrease in mean procedure cost ($9728 vs. $12,127; p = 0.002), shorter time to achieve modified thrombolysis in cerebral infarction ≥2b reperfusion (38.30 min vs. 53.26 min; p = 0.018), and shorter puncture to procedure completion time (46.42 min vs. 62.38 min; p = 0.022). Additionally, the mean procedural cost when using the ADAPT technique supported by the Zoom catheters was significantly lower than the Solumbra technique ($5754 ± $2806 vs. $13,498 ± $3244, p < 0.001). There were no differences in the rate of hemorrhage between the pre-Zoom group (17.9%) and the post-Zoom group (20.6%), p = 0.690. CONCLUSION: The study demonstrated significant benefits, including cost reduction and shorter time to achieve reperfusion in patients treated with Zoom aspiration catheters. These findings support the use of angled-tip catheters in acute ischemic stroke management.

Mechanical Venous Thrombectomy Using Indigo Aspiration System: A Case Report.

We present a case of successful endovascular thrombectomy of cerebral venous sinus thrombosis utilizing Penumbra's Indigo Aspiration System (Penumbra Inc., Place Alameda, CA), a minimally invasive system with a large-lumen (Indigo System CAT7, 7F) catheter predominantly used for the removal of thromboembolism involving the peripheral arterial and venous systems. A 30-year-old female presented with a seizure and focal neurological deficits and was found to have a left posterior temporal lobe hemorrhagic infarct secondary to an extensive cerebral venous sinus thrombosis extending from the left transverse sinus to the ipsilateral internal jugular bulb. We considered the combination of seizure, motor deficit, and hemorrhagic infarct high-risk features for poor response to standard medical therapy with therapeutic anticoagulation. Therefore, we performed a mechanical venous thrombectomy with the above device in addition to anticoagulation treatment with heparin infusion. This combination therapy resulted in a technically successful radiographic recanalization of the involved sinuses and an excellent functional outcome at follow-up. This case demonstrates that this trackable, atraumatic, large-bore system was safe and efficacious in the cerebral venous system, permitting near-complete thrombus removal.

Predicting poor response to anti-coagulation therapy in cerebral venous thrombosis using a simple clinical-radiological score.

BACKGROUND: Multiple studies have attempted to determine predictors of poor clinical outcomes in cerebral venous thrombosis (CVT). Fewer studies target to identify predictors of poor response to anticoagulation therapy in CVT. OBJECTIVE: We aimed to determine the predictors of poor clinical response to therapeutic anticoagulation in patients with acute CVT. METHODS: We performed a retrospective analysis of patients therapeutically anticoagulated for acute CVT. We defined poor clinical outcomes as death, need for mechanical thrombectomy during the hospitalization, or a modified Rankin Scale (mRS) > 3 at clinical follow-up. Bivariate and multivariate analyses identified factors associated with poor outcomes in anticoagulated patients for acute CVT, and we used the identified factors to create the PRACT-CVT (Poor Response to Anticoagulation Therapy in CVT) score. RESULTS: We included 109 patients anticoagulated with acute CVT. The mean patient age was 37 years old (SD 19); nine patients were > 65 years, ten patients were < 10 years, and 64 (59%) were female. Twenty-one (19%) patients had poor clinical outcomes. Age > 65 or < 10 years (OR: 3.16, 95% CI: 1.06-9.44), a GCS ≤ 12 upon presentation (OR: 19.2, 95% CI: 4.05-91.4), focal motor deficits at admission (OR: 5.03, 95% CI: 1.64-15.44), clinical deterioration following admission (OR: 28.18, CI: 4.81-164.86), seizures following admission (OR: 5.59, 95% CI: 1.27-24.51), evidence of brain bleeding/ischemia on admission (OR: 4.67, 95% CI: 1.42-15.34), involvement of the superior sagittal sinus (OR: 3.88, CI: 1.33-11.32), or involvement of both transverse sinuses (OR: 3.87, 95% CI: 1.01-14.90) predicted poor clinical outcome despite therapeutic anticoagulation. A PRACT-CVT score (0-22 points) of ≥ 7 points provided a sensitivity of 71% and a specificity of 95% for predicting poor clinical outcomes with anticoagulation alone. CONCLUSION: Patients with acute CVT aged > 65 or < 10 years old, presenting with a GCS ≤ 12, with focal motor deficits, showing clinical deterioration after admission, having clinical seizures during hospitalization, with brain bleeding/ischemia on initial neuroimaging, involvement of the superior sagittal sinus, or involvement of both transverse sinuses had poor response to anticoagulation. Clinicians may employ the PRACT-CVT score to predict poor response to anticoagulation for acute CVT.