Machine Learning Automated Detection of Large Vessel Occlusion From Mobile Stroke Unit Computed Tomography Angiography

Stroke ◽  
2021 ◽  
Author(s):  
Alexandra L. Czap ◽  
Mersedeh Bahr-Hosseini ◽  
Noopur Singh ◽  
Jose-Miguel Yamal ◽  
May Nour ◽  
...  

Background and Purpose: Prehospital automated large vessel occlusion (LVO) detection in Mobile Stroke Units (MSUs) could accelerate identification and treatment of patients with LVO acute ischemic stroke. Here, we evaluate the performance of a machine learning (ML) model on CT angiograms (CTAs) obtained from 2 MSUs to detect LVO. Methods: Patients evaluated on MSUs in Houston and Los Angeles with out-of-hospital CTAs were identified. Anterior circulation LVO was defined as an occlusion of the intracranial internal carotid artery, middle cerebral artery (M1 or M2), or anterior cerebral artery vessels and determined by an expert human reader. A ML model to detect LVO was trained and tested on independent data sets consisting of in-hospital CTAs and then tested on MSU CTA images. Model performance was determined using area under the receiver-operator curve statistics. Results: Among 68 patients with out-of-hospital MSU CTAs, 40% had an LVO. The most common occlusion location was the middle cerebral artery M1 segment (59%), followed by the internal carotid artery (30%), and middle cerebral artery M2 (11%). Median time from last known well to CTA imaging was 88.0 (interquartile range, 59.5–196.0) minutes. After training on 870 in-hospital CTAs, the ML model performed well in identifying LVO in a separate in-hospital data set of 441 images with area under receiver-operator curve of 0.84 (95% CI, 0.80–0.87). ML algorithm analysis time was under 1 minute. The performance of the ML model on the MSU CTA images was comparable with area under receiver-operator curve 0.80 (95% CI, 0.71–0.89). There was no significant difference in performance between the Houston and Los Angeles MSU CTA cohorts. Conclusions: In this study of patients evaluated on MSUs in 2 cities, a ML algorithm was able to accurately and rapidly detect LVO using prehospital CTA acquisitions.

2018 ◽  
Vol 25 (2) ◽  
pp. 202-207 ◽  
Author(s):  
Krishna Amuluru ◽  
James P Ho ◽  
Fawaz Al-Mufti ◽  
Sten Solander ◽  
Charles E Romero

A fetal posterior cerebral artery (FPCA) is an anatomic variant in which the posterior cerebral artery is an embryological derivative of the internal carotid artery. Although most cases of ischemic strokes in patients with FPCAs involve embolic infarcts, emergent large vessel occlusion of a FPCA is extremely rare. We present two cases of successful endovascular intervention for emergent occlusion of a FPCA, one of which is only the second reported case of a mechanical thrombectomy of a FPCA. We review the embryology of FPCA, the controversy regarding its association with cerebral infarcts, and various approaches used in the treatment of such occlusive lesions.


2019 ◽  
Vol 10 ◽  
pp. 205
Author(s):  
Seiei Torazawa ◽  
Hideaki Ono ◽  
Tomohiro Inoue ◽  
Takeo Tanishima ◽  
Akira Tamura ◽  
...  

Background: Very large and giant aneurysms (≥20 mm) of the internal carotid artery (ICA) bifurcation (ICAbif) are definitely rare, and optimal treatment is not established. Endovascular treatments are reported as suboptimal due to difficulties of complete occlusion and tendencies to recanalization. Therefore, direct surgery remains an effective strategy if the clipping can be performed safely and reliably, although very difficult. Case Description: Two cases of ICAbif aneurysms (>20 mm) were treated. Prior assistant superficial temporal artery (STA)-middle cerebral artery (MCA) bypass was performed to avoid ischemic complications during prolonged temporary occlusion of the arteries in both cases. In Case 1 (22-mm aneurysm), the dome was inadvertently torn in applying the clip because trapping had resulted in insufficient decompression. Therefore, in Case 2 (28-mm aneurysm), almost complete trapping of the aneurysm and subsequent dome puncture was performed, and the aneurysm was totally deflated by suction from the incision. This complete aneurysm decompression allowed safe dissection and successful clipping. Conclusion: Trapping, deliberate aneurysm dome puncture, and suction decompression from the incision in conjunction with assistant STA-MCA bypass can achieve complete aneurysm deflation, and these techniques enable safe dissection of the aneurysm and direct clipping of the aneurysm neck. Direct clipping with this technique for very large and giant ICAbif aneurysms may be the optimal treatment choice with the acceptable outcome if endovascular treatment remains suboptimal.


Neurosurgery ◽  
2017 ◽  
Vol 80 (2) ◽  
pp. 235-247 ◽  
Author(s):  
Christopher M. Owen ◽  
Nicola Montemurro ◽  
Michael T. Lawton

Abstract BACKGROUND: Blister aneurysms of the supraclinoid internal carotid artery (ICA) are challenging lesions with high intraoperative rupture rates and significant morbidity. An optimal treatment strategy for these aneurysms has not been established. OBJECTIVE: To analyze treatment strategy, operative techniques, and outcomes in a consecutive 17-year series of ICA blister aneurysms treated microsurgically. METHODS: Seventeen patients underwent blister aneurysm treatment with direct clipping, bypass and trapping, or clip-reinforced wrapping. RESULTS: Twelve aneurysms (71%) were treated with direct surgical clipping. Three patients required bypass: 1 superficial temporal artery to middle cerebral artery bypass, 1 external carotid artery to middle cerebral artery bypass, and 1 ICA to middle cerebral artery bypass. One patient was treated with clip-reinforced wrapping. Initial treatment strategy was enacted 71% of the time. Intraoperative rupture occurred in 7 patients (41%), doubling the rate of a poor outcome (57% vs 30% for patients with and without intraoperative rupture, respectively). Severe vasospasm developed in 9 of 16 patients (56%). Twelve patients (65%) were improved or unchanged after treatment, and 10 patients (59%) had good outcomes (modified Rankin Scale scores of 1 or 2). CONCLUSION: ICA blister aneurysms can be cautiously explored and treated with direct clipping as the first-line technique in the majority of cases. Complete trapping of the parent artery with temporary clips and placing permanent clip blades along normal arterial walls enables clipping that avoids intraoperative aneurysm rupture. Trapping/bypass is used as the second-line treatment, maintaining a low threshold for bypass with extensive or friable pathology of the carotid wall and in patients with incomplete circles of Willis.


2010 ◽  
pp. 504-517
Author(s):  
George Samandouras

Chapter 9.1 covers critical neurovascular brain anatomy, including internal carotid artery, the middle cerebral artery, the anterior cerebral artery, the vertebral arteries (VAs), the basilar artery (BA), and the venous system.


Stroke ◽  
2020 ◽  
Vol 51 (9) ◽  
Author(s):  
Khalid Al-Dasuqi ◽  
Seyedmehdi Payabvash ◽  
Gerardo A. Torres-Flores ◽  
Sumita M. Strander ◽  
Cindy Khanh Nguyen ◽  
...  

Background and Purpose: We aim to examine effects of collateral status and post-thrombectomy reperfusion on final infarct distribution and early functional outcome in patients with anterior circulation large vessel occlusion ischemic stroke. Methods: Patients with large vessel occlusion who underwent endovascular intervention were included in this study. All patients had baseline computed tomography angiography and follow-up magnetic resonance imaging. Collateral status was graded according to the criteria proposed by Miteff et al and reperfusion was assessed using the modified Thrombolysis in Cerebral Infarction (mTICI) system. We applied a multivariate voxel-wise general linear model to correlate the distribution of final infarction with collateral status and degree of reperfusion. Early favorable outcome was defined as a discharge modified Rankin Scale score ≤2. Results: Of the 283 patients included, 129 (46%) had good, 97 (34%) had moderate, and 57 (20%) had poor collateral status. Successful reperfusion (mTICI 2b/3) was achieved in 206 (73%) patients. Poor collateral status was associated with infarction of middle cerebral artery border zones, whereas worse reperfusion (mTICI scores 0–2a) was associated with infarction of middle cerebral artery territory deep white matter tracts and the posterior limb of the internal capsule. In multivariate regression models, both mTICI ( P <0.001) and collateral status ( P <0.001) were among independent predictors of final infarct volumes. However, mTICI ( P <0.001), but not collateral status ( P =0.058), predicted favorable outcome at discharge. Conclusions: In this cohort of patients with large vessel occlusion stroke, both the collateral status and endovascular reperfusion were strongly associated with middle cerebral artery territory final infarct volumes. Our findings suggesting that baseline collateral status predominantly affected middle cerebral artery border zones infarction, whereas higher mTICI preserved deep white matter and internal capsule from infarction; may explain why reperfusion success—but not collateral status—was among the independent predictors of favorable outcome at discharge. Infarction of the lentiform nuclei was observed regardless of collateral status or reperfusion success.


1988 ◽  
Vol 8 (5) ◽  
pp. 697-712 ◽  
Author(s):  
Norihiro Suzuki ◽  
Jan Erik Hardebo ◽  
Christer Owman

In order to clarify the origins and pathways of vasoactive intestinal polypeptide (VlP)-containing nerve fibers in cerebral blood vessels of rat, denervation experiments and retrograde axonal tracing methods (true blue) were used. Numerous VIP-positive nerve cells were recognized in the sphenopalatine ganglion and in a mini-ganglion (internal carotid mini-ganglion) located on the internal carotid artery in the carotid canal, where the parasympathetic greater superficial petrosal nerve is joined by the sympathetic fibers from the internal carotid nerve, to form the Vidian nerve. VIP fiber bridges in the greater deep petrosal nerve and the internal carotid nerve reached the wall of the internal carotid artery. Two weeks after bilateral removal of the sphenopalatine ganglion or sectioning of the structures in the ethmoidal foramen, VIP fibers in the anterior part of the circle of Willis completely disappeared. Very few remained in the middle cerebral artery, the posterior cerebral artery, and rostral two-thirds of the basilar artery, whereas they remained in the caudal one-third of the basilar artery, the vertebral artery, and intracranial and carotid canal segments of the internal carotid artery. One week after application of true blue to the middle cerebral artery, dye accumulated in the ganglion cells in the sphenopalatine, otic and internal carotid mini-ganglion; some of the cells were positive for VIP. The results show that the VIP nerves in rat cerebral blood vessels originate: (a) in the sphenopalatine, and otic ganglion to innervate the circle of Willis and its branches from anterior and caudally and (b) from the internal carotid mini-ganglion to innervate the internal carotid artery at the level of the carotid canal and to some extent its intracranial extensions.


Brain ◽  
1970 ◽  
Vol 93 (1) ◽  
pp. 199-210 ◽  
Author(s):  
FRANZ SINDERMANN ◽  
DORIS BECHINGER ◽  
JOHANNES DICHGANS

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