DEEP MOVEMENT: Deep learning of movie files for management of endovascular thrombectomy.

OBJECTIVES: Treatment and outcomes of acute stroke have been revolutionised by mechanical thrombectomy. Deep learning has shown great promise in diagnostics but applications in video and interventional radiology lag behind. We aimed to develop a model that takes as input digital subtraction angiography (DSA) videos and classifies the video according to (1) the presence of large vessel occlusion (LVO), (2) the location of the occlusion, and (3) the efficacy of reperfusion. METHODS: All patients who underwent DSA for anterior circulation acute ischaemic stroke between 2012 and 2019 were included. Consecutive normal studies were included to balance classes. An external validation (EV) dataset was collected from another institution. The trained model was also used on DSA videos post mechanical thrombectomy to assess thrombectomy efficacy. RESULTS: In total, 1024 videos comprising 287 patients were included (44 for EV). Occlusion identification was achieved with 100% sensitivity and 91.67% specificity (EV 91.30% and 81.82%). Accuracy of location classification was 71% for ICA, 84% for M1, and 78% for M2 occlusions (EV 73, 25, and 50%). For post-thrombectomy DSA (n = 194), the model identified successful reperfusion with 100%, 88%, and 35% for ICA, M1, and M2 occlusion (EV 89, 88, and 60%). The model could also perform classification of post-intervention videos as mTICI < 3 with an AUC of 0.71. CONCLUSIONS: Our model can successfully identify normal DSA studies from those with LVO and classify thrombectomy outcome and solve a clinical radiology problem with two temporal elements (dynamic video and pre and post intervention). KEY POINTS: • DEEP MOVEMENT represents a novel application of a model applied to acute stroke imaging to handle two types of temporal complexity, dynamic video and pre and post intervention. • The model takes as an input digital subtraction angiograms of the anterior cerebral circulation and classifies according to (1) the presence or absence of large vessel occlusion, (2) the location of the occlusion, and (3) the efficacy of thrombectomy. • Potential clinical utility lies in providing decision support via rapid interpretation (pre thrombectomy) and automated objective gradation of thrombectomy outcomes (post thrombectomy).

Embolization of a traumatic arteriovenous fistula between the middle meningeal artery and middle meningeal vein in a child with pulsatile tinnitus.

Traumatic arteriovenous fistulas (AVFs) involving the middle meningeal artery (MMA) are uncommon lesions and rare in the pediatric population. An adolescent with headaches developed a bruit and a rhythmic "swooshing" noise in the left ear 9 weeks after a traumatic brain injury involving a left temporal bone fracture. An MRA of the brain demonstrated an enlarged left MMA and arterialized flow in the left middle meningeal vein (MMV), suggestive of an AVF. Cerebral angiography confirmed and characterized the left MMA-MMV fistula, which drained into the pterygoid plexus. The patient underwent transarterial coil embolization, with successful obliteration of the fistulous connection, and her tinnitus resolved. This case illustrates the importance of recognizing a post-traumatic AVF in a pediatric patient with pulsatile tinnitus, and that endovascular treatment by coil embolization is a safe and effective treatment option.

Now that the door is open: an update on ischemic stroke pharmacotherapeutics for the neurointerventionalist.

The last 10 years have seen a major shift in management of large vessel ischemic stroke with changes towards ever-expanding use of reperfusion therapies (intravenous thrombolysis and mechanical thrombectomy). These strategies 'open the door' to acute therapeutics for ischemic tissue, and we should investigate novel therapeutic approaches to enhance survival of recently reperfused brain. Key insights into new approaches have been provided through translational research models and preclinical paradigms, and through detailed research on ischemic mechanisms. Additional recent clinical trials offer exciting salvos into this new strategy of pairing reperfusion with neuroprotective therapy. This pairing strategy can be employed using drugs that have shown neuroprotective efficacy; neurointerventionalists can administer these during or immediately after reperfusion therapy. This represents a crucial moment when we emphasize reperfusion, and have the technological capability along with the clinical trial experience to lead the way in multiprong approaches to stroke treatment.

Urinary bladder retention secondary to intranasal administration of oxymetazoline "Afrin" for intra-arterial chemotherapy.

Selective ophthalmic artery infusion of chemotherapy (SOAIC) has emerged as the standard of care for retinoblastoma (RB). Intranasal oxymetazoline (INO), Afrin, is often intraoperatively administered adjunctively to optimize flow to the orbit. There has been one report to date that suggests the adjunctive use of INO has led to systemic side effects. To our knowledge, this is the first documented case of INO causing urinary retention in a patient undergoing SOAIC, and the recommended treatment.

An ischemic myelopathy case series: Flaccid paraplegia following a spike ball save and numbness while walking normally.

Spinal cord infarctions in children are rare and early magnetic resonance imaging studies are often negative. A high clinical suspicion must be maintained to identify stroke and initiate workup for underlying etiology to suggest appropriate treatment. We present two cases of spinal cord infarction without major preceding trauma. The first was caused by disc herniation and external impingement of a radiculomedullary artery and the second was due to fibrocartilaginous embolism with classic imaging findings of ventral and dorsal cord infarctions, respectively. These cases were treated conservatively with diagnostic workup and aspirin, though additional treatments which can be considered with prompt diagnosis are also explored in our discussion. Both cases recovered the ability to ambulate independently within months. Case 1 is attending college and ambulates campus with a single-point cane. Case 2 ambulates independently, though has some difficulty with proprioception of the feet so uses wheelchairs for long-distance ambulation.

Fetal Cerebral Sinovenous Thrombosis and Dural Sinus Malformation.

BACKGROUND: Fetal cerebral sinovenous thrombosis (CSVT) and dural sinus malformation (DSM) are rare types of fetal cerebral venous pathology that are becoming increasingly recognized as fetal imaging advances. Fetal DSMs are a common source of fetal CSVT, although CSVT may occur without a DSM. The literature on these disorders is limited. METHODS: Cases of fetal CSVT and DSM were identified retrospectively through a query of the Indiana University Health fetal imaging archive from 2007 to 2021. RESULTS: Seven cases were identified, all of whom were alive at birth. A DSM was present in six. Treatments after birth included enoxaparin sodium (3), embolization (3), and shunt placements (1). Five cases had documented regression or complete resolution of the thrombus and/or malformation. One was lost to follow-up, one died from complications of hydrocephalus at nine months, one was receiving physical and occupational therapy at last follow-up at three months, one had concern for autism and mild gait abnormality at 21 months, two had concern for speech delay (18 months and 24 months), and one had normal development at most recent follow-up (four years). CONCLUSIONS: Positive short-term outcomes may occur for some cases of fetal CSVT and DSM. However, risk factors and best treatments are not clear, and long-term outcome data are limited. There is a need for further study.

Bow Hunter's Syndrome in Children: A Review of the Literature and Presentation of a New Case in a 12-Year-Old Girl.

BACKGROUND: Bow hunter's syndrome, or occlusion of the vertebral artery with head rotation leading to ischemia and sometimes stroke, is rarely described in children. The authors review the literature and present a new case. METHODS: Both OVID dating back to 1946 and PubMed records were reviewed using the terms ("Bow hunter syndrome" OR "bow hunter's") OR "rotational vertebral artery occlusion" combined with "child," and limited to English language. SCOPUS and the bibliographies of cases found in the search were used to identify additional articles. RESULTS: Twelve articles were found describing 25 patients; there were 26 patients when combined with our case. Ages ranged from 1 to 18 years. Most (88.5%, 23/26) were male. Medical treatments included aspirin, clopidogrel, abciximab, enoxaparin, warfarin, and cervical collar. Stenting was tried in 2 cases but did not work long-term. Surgical treatments included decompression, cervical fusion, or a combination. We present a new case of a 12-year-old girl with recurrent stroke who had bilateral vascular compression only visible on provocative angiographic imaging with head turn. She was referred for cervical fusion, and abnormal ligamentous laxity was noted intraoperatively. CONCLUSIONS: Bow hunter's syndrome is a rare but important cause of stroke since many of the patients experience recurrent strokes before the diagnosis is made. Reasons for the male predominance are unclear. Provocative angiography plays a key role in diagnosis, and both medical treatment and neurosurgical intervention may prevent recurrence.

Cervical spinal dural fistulas leading to remote thoracolumbar myelopathy: A diagnostic pitfall.

PURPOSE OF REVIEW: Spinal dural arteriovenous fistulas (SDAVFs) are abnormal connections between 1 or more radiculomeningeal arteries and a single radiculomedullary vein draining into the perimedullary venous system. SDAVFs present in older patients with a progressive myelopathy caused by diffuse spinal venous hypertension. The discrepancy between the focal nature of the arteriovenous shunt and the extent of the induced myelopathy is a classic feature of SDAVFs related to the coexistence of diffuse spinal venous drainage impairment. RECENT FINDINGS: We describe 3 cases of cervical SDAVFs (at C1, C4, and C7) presenting with a myelopathy that spared the cervical spinal cord and, in 2 instances, the upper thoracic cord. This is to our knowledge the first observations of cervical SDAVFs with MRI showing absent or subtle flow voids and presenting remote thoracolumbar myelopathy without cervical cord involvement. SUMMARY: A considerable distance may separate low-flow spinal arteriovenous fistulas from the spinal cord damage they produce. These observations emphasize the importance of performing a complete spinal angiogram when investigating a vascular myelopathy of any location and extent.

Mid-term follow-up of staged bilateral internal carotid artery aneurysm treatment with Pipeline embolization.

BACKGROUND: Endovascular treatment of large complex morphology aneurysms is challenging. High recanalization rates have been reported with techniques such as stent-assisted coiling and balloon-assisted coiling. Flow diverter devices have been introduced to improve efficacy outcomes and recanalization rates. Thromboembolic complications and in-device stenosis are certainly more worrisome when treatment of bilateral internal carotid arteries has been performed. This study aimed to report our experience with mid-term imaging follow-up of staged bilateral Pipeline embolization device placement for the treatment of bilateral internal carotid artery aneurysms. METHODS: We reviewed the clinical, angiographic, and follow-up imaging data in all consecutive patients treated with bilateral internal carotid artery aneurysms who underwent elective Pipeline embolization. RESULTS: Six female patients were treated, harboring a total of 13 aneurysms. Of these, 60% were asymptomatic. Diplopia and headache were the most common symptoms. The most common location was the paraclinoid segment (6/13), including by cavernous segment (4/13) and ophthalmic segment (2/13). Successful delivery of the device was achieved in 12 cases. Difficult distal access precluded the deployment of the device in one case. The treatment was always staged with at least eight weeks' difference between the two procedures. All aneurysm necks were covered completely. There were no periprocedural complications. Angiographic follow-up ranged between 3 and 12 months, and computed tomography angiogram follow-up ranged between 2 and 24 months. Complete aneurysm occlusion was achieved in all cases. CONCLUSION: In our series, Pipeline deployment for the treatment of bilateral internal carotid artery aneurysms in a staged fashion is safe and feasible. Mid-term imaging follow-up showed permanent occlusion of all the treated aneurysms.

Reducing Radiation Dose for High-resolution Flat-panel CT Imaging of Superior Semicircular Canal Dehiscence.

OBJECTIVE: High-resolution flat panel computed tomography (FPCT) is useful for the evaluation of temporal bone pathologies. While radiation exposure remains a concern, efforts have been devoted to reduce dose, while maintaining image quality. We hypothesize that removing the antiscatter grid (ASG) results in decreased radiation exposure, while maintaining diagnostic image quality for the evaluation of superior semicircular canal dehiscence (SSCD). METHODS: Ten patients with clinical suspicion for SSCD participated in this prospective study. Two sequential collimated 20-second FPCT acquisitions were performed (first: grid in; second: grid removed) in all patients. Secondary reconstructions were created by manually generating the volume of interest to include the middle ear using a voxel size of 0.1 mm and 512 × 512 matrix. Radiation dose parameters (air kerma (Ka,r) in mGy and dose area product (DAP) in µGym) were recorded. Three reviewers analyzed images for the ability to diagnose SSCD, to identify the stapes crurae, and to determine if an ASG was present. RESULTS: The average Ka,r and DAP for the grid-in acquisitions were 246.7 mGy (SD 47.9) and 2838.0 µGym (SD 862.8), versus 160.2 mGy (SD 33.2) and 2026.3 µGym (SD 644.8) for the grid-out acquisitions, respectively (p<0.001 for both Ka,r and DAP). Radiation exposure was reduced by approximately 30% solely by removing the ASG. All reviewers correctly identified all patients with SSCD (confirmed at surgery), with mean AUC of 0.99 (κ = 0.90). CONCLUSION: Removing the antiscatter grid during FPCT imaging of the temporal bones is a simple and effective way to reduce radiation exposure while maintaining diagnostic image quality for the evaluation of SSCD.