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Minimally-invasive surgical techniques for intracerebral hemorrhage (ICH) evacuation use imaging to guide the suction, lysing and/or drainage from the hemorrhage site via various designs. A previous international surgical study has shown that reduction of hematoma volume below 15 ml is indicative of improved long term patient outcomes. The study noted a need for tools to periodically visualize remaining clot during intervention to increase the likelihood of evacuating sufficient clot volumes without endangering rebleeds. Robust segmentation of MRI could guide surgeons and radiologists regarding remaining regions and approaches for prudent evacuation. We thus propose a Convolutional Neural Network (CNN) to identify and autonomously segment clot and peripheral edema in MR images of the brain and generate an estimate of the remaining clot volume. We used a retrospective, locally-acquired dataset of ICH patient scans taken on 3 T MRI scanners. Three sets of ground truth manual segmentations were independently generated by two imaging scientists and one radiology fellow. Evaluation of clot age was determined based on relative contrast of hemorrhage components and reviewed by a neurosurgeon. Model accuracy was determined by pixel-wise Dice coefficient (DC) calculations between each ground truth manual segmentation and the machine-derived autonomous segmentations. The model produced autonomous segmentations of clot core with an average DC of 0.75 ± 0.21 relative to manual segmentations of the same scans. For edema, it produced segmentations with an average DC of 0.68 ± 0.16 relative to manual. From these pixel-wise segmentations, clot volume can be calculated. Model-produced segmentations underestimated clot volumes by an average of 17% relative to ground-truth. The machine learning models were able to identify and segment volumes of ICH components swiftly and accurately. [ABSTRACT FROM AUTHOR]

Highlights • Delayed aneurysm rupture is a rare but serious complication of FDS. • No clear cause of delayed rupture has been described, though thrombus formation and flow alteration are proposed mechanisms. • Our patients all experienced an increase in intrasaccular pressure following FDS deployment. [ABSTRACT FROM AUTHOR]

Objective: Pediatric spinal arteriovenous malformations (AVMs) are rare and complex lesions to treat. There are few reports of the endovascular and microsurgical treatment of these lesions in the pediatric population, and the treatment outcomes of these patients are not well described. The aim of this study was the clinical and radiographic outcomes of spinal AVMs in pediatric patients treated via endovascular and microsurgical modalities. Methods: We identified nine children (5 boys, 4 girls; average age 11 years, range 3–17 years) treated for spinal AVMs between 1998 and 2010. Their charts were reviewed. Results: Spinal AVMs most frequently involved the thoracic spinal cord. Four patients had associated Klippel-Trènaunay-Weber syndrome and one had hereditary hemorrhagic telangiectasia. There were two intramedullary, four conus medullaris, and three mixed extradural-intradural lesions. The most common presenting signs and symptoms were subarachnoid hemorrhage (n = 3) and paraparesis (n = 5). Endovascular intervention was used exclusively in two patients, and combined endovascular and microsurgical intervention was used in four patients. Surgery was the sole treatment in three patients with excellent results. There were two treatment-related complications: one case of subarachnoid hemorrhage and one case of scrotal swelling. The mean follow-up was 28.5 months and the median was 8 months (range, 1–65 months). The mean pretreatment World Health Organization (WHO)/Zubrod score was 2.4 (range, 1–4), and the mean post-treatment score was 1.4 (range, 0–4). One patient (11%) had a recurrence. Conclusions: Pediatric spinal AVMs require complex combined microsurgical and endovascular techniques to achieve favorable outcomes. [Copyright &y& Elsevier]

Abstract: The differential diagnosis of new or worsening focal neurologic deficits on emergence from anesthesia is broad. Cerebral ischemia or hemorrhage, focal seizures, and acute metabolic abnormalities can all result in similar neurologic findings. Intravenously administered anesthetic agents also have been reported to cause new or worsening focal neurologic deficits in patients with a history of preexisting deficits. A patient who suffered such a reversible deficit related to anesthesia is presented. [Copyright &y& Elsevier]

Flow-diverting stents (FDS) are relatively safe and highly efficacious in treating cerebral aneurysms; however, a small subset of patients experience devastating hemorrhagic complications owing to presumed alterations in local aneurysm and distal cerebral blood flow. The downstream effects of FDS on distal cerebral blood flow is not well understood, but isolated reports of hyperperfusion injury have been described in the literature. We investigate the incidence and clinical factors contributing to abnormal cerebral blood flow after FDS placement. A retrospective analysis of patients undergoing FDS for elective aneurysm treatment between 2014–2017 was performed. Patients who underwent perfusion imaging within 24-hours posttreatment were included for further analysis. Univariate and multivariate analyses were performed to assess the impact of multiple variables on the postoperative perfusion changes. A total of 69 patients underwent FDS therapy to treat unruptured intracranial aneurysms. Thirteen patients (18.8%) developed abnormal perfusion changes. A significant difference of the median was found in aneurysm projection width, depth, neck width, calculated approximate volume, and size ratio between the hypoperfused, normal, and hyperperfusion cases. On multivariate analysis, history of smoking (P = 0.0117), and approximate calculated volume (P = 0.0145) were significant predictors of hyperperfusion identified on posttreatment imaging. This study yielded several novel findings. We demonstrate that cerebral blood flow alterations will occur in a significant subset of patients undergoing FDS treatment. We also provide new evidence that aneurysm volume and history of smoking may predict the developing of postoperative perfusion anomalies. Future studies are needed to evaluate the clinical ramifications of cerebral blood flow disruption in large prospective studies. [ABSTRACT FROM AUTHOR]

Objective: We described our endovascular techniques for the recanalization of chronic occlusions of the brachiocephalic and subclavian arteries. Given their large caliber, origins from the aorta, and proximity to the carotid and vertebral arteries, various complex endovascular techniques are required to achieve revascularization. Navigation of distal embolic protection devices into the carotid and vertebral arteries mandates varied catheter approaches. Methods: Four women harboring chronic occlusions of the brachiocephalic and subclavian arteries were evaluated for their presenting symptoms, neurologic status, endovascular treatment, complications, and radiographic and clinical follow-up. We reviewed three specific treatment scenarios and analyzed predictive factors associated with treatment failure. Results: Three chronic occlusions of the subclavian artery and 1 chronic occlusion of the brachiocephalic artery were identified in the four patients. All patients previously had experienced a stroke in the affected vascular territory or transient ischemic attacks from steal syndromes. Three target vessels were reopened successfully with angioplasty and stenting. In all cases, distal embolic protection devices were used, and multiple access points, including radial, brachial, and femoral catheterization, were required. Angiographic follow-up (range, 6-18 months) demonstrated stable patency of the stents in the three successfully treated patients. There were no transient or permanent complications. Conclusions: Endovascular recanalization of the great vessels with the use of distal embolic protection devices requires multiple catheters and complex endovascular techniques but is feasible and safe. A significant percentage of these occlusions can likely be reopened through endovascular techniques. [ABSTRACT FROM AUTHOR]

Atypical teratoid/rhabdoid tumor (AT/RT) is a rare tumor that is most frequently encountered in the pediatric patient population. AT/RT accounts for approximately 1%−2% of all pediatric central nervous system tumors and roughly 10%−20% of tumors in patients younger than 3 years of age. While AT/RT has been encountered in the adult population, the vast majority of the cases reported occur in the supratentorial space. In the existing literature, only 3 adult cases that arise from the cerebellum have ever been reported. A 38-year-old female presented with 6 months of worsening nausea, emesis, vertigo, diplopia, and coordination difficulty. Magnetic resonance imaging revealed a T1 avidly contrast-enhancing mass, composed of both cystic and solid areas, extending from the cerebellum into the fourth ventricle. Following a gross total resection, surgical pathology was consistent with AT/RT, with tumor cell loss of integrase interactor-1 (INI-1) observed via immunohistochemical staining. This case represents just the fourth ever reported case of AT/RT arising from the cerebellum in an adult and the oldest reported age to date of a cerebellar AT/RT occurring in a female. Due to the paucity of reported adult AT/RT cases, little is known about adults with AT/RT. Further reports will function to improve the general understanding of AT/RT in the adult population. [ABSTRACT FROM AUTHOR]

It can sometimes be challenging to find a suitable clip to treat an unusual aneurysm, or when the surrounding anatomy is unusual, especially in resource-limited environments. We describe a method to modify aneurysm clips based on the method originated by Sugita et al in 1985. Herein clip modification (Clip-Mod) is used to treat anatomically difficult anterior communicating artery aneurysms. The Department of Neurological Surgery database was reviewed to find aneurysm patients treated using modified aneurysm clips. Clip-Mod was performed during surgery by shortening the tines of titanium aneurysm clips by abrasion applied from the side of a standard 3-mm surgical diamond drill bit under constant irrigation. Note that the thickness of the tines and the clip spring were not modified or contacted by the drill. Four cases used modified aneurysm clips, from 648 total clip-treated aneurysms (0.6%) by 2 surgeons over a 14-year period. Three patients presented with subarachnoid hemorrhages that were determined to be due to anterior communicating artery aneurysms. One patient presented with an incidental unruptured anterior communicating artery aneurysm. All 4 patients were treated with 3-mm titanium clips shortened intraoperatively to 1- to 2-mm lengths, to achieve aneurysm obliteration without stenosing parent or perforating vessels. All 4 patients have done well clinically with no reoccurrences after 2–6 years' follow-up, which included angiographic evaluation. The use of this "Clip-Mod" technique thus appears useful for anterior communicating artery aneurysms. Clip-Mod could also be considered for treating other aneurysms when the "perfect" length clip is not available. [ABSTRACT FROM AUTHOR]

Objective To evaluate the relationship between blood–brain barrier disruption and transient neurologic deficits (TNDs) after neuroendovascular interventions (NEIs) using postcontrast T2/FLAIR (pcFLAIR) imaging. Methods This is a prospective study of 41 consecutive patients undergoing flow diversion therapy for unruptured aneurysm treatment. Patients underwent postprocedural magnetic resonance imaging within 24 hours of the procedure, including diffusion-weighted imaging (DWI) and pcFLAIR sequences. Regression analyses were performed to identify risk factors for developing TNDs. Results In total, 13 patients (31.7%) developed neurologic complications ranging from visual field defects to dense hemiplegia. All deficits were transient, resolving spontaneously within 72 hours. Five of 13 patients (38.5%) with TNDs had presence of lesions on DWI whereas the remaining 8 patients (61.5%) did not. In contrast, all patients who developed TNDs had leptomeningeal enhancement on pcFLAIR imaging, and no patient with normal pcFLAIR imaging developed TNDs. Regression analysis revealed the extent of pcFLAIR enhancement is associated with development of postprocedure neurologic deficits (P < 0.0001). Video electroencephalography monitoring was performed in 4 symptomatic patients manifesting severe deficits. In all instances electroencephalography demonstrated ipsilateral hemispheric slowing and eventual resolution corresponding to ensuing clinical improvement. Only 1 of these 4 patients presented with a lesion on DWI. Conclusions This study challenges conventional dogma that TNDs are ischemic in etiology and suggests blood–brain barrier impairment may be a potential alternative mechanism. These findings are applicable to stroke and other reversible neurologic diseases. Highlights • DWI does not fully explain the present or severity of neurologic deficits after cerebral angiographic procedures. • LME on postcontrast FLAIR is consistent with blood–brain barrier (BBB) impairment and may result in neurologic complications after cerebral angiophy. • pcFLAIR LME is a highly sensitive imaging biomarker of BBB disruption seen in a majority of patients undergoing NEI. • The extent of LME directly predicts the development of reversible neurologic complications seen after NEI. • BBB disruption results in increased permeability of the central nervous system to neurotoxic drugs, which facilitates neurologic dysfunction/TNDs. [ABSTRACT FROM AUTHOR]

Background Embolic strokes mainly result from cardiac or vascular origins, but there are instances when they can arise from iatrogenic foreign bodies. Catheter coatings or retained microcatheters are mainly implicated in foreign body embolism following neuroendovascular intervention. However, there are no known descriptions for free-floating and/or dislodged microcatheter fragments in the literature. Case Description We report the clinical details, imaging findings, and management of a 69-year-old woman who underwent elective pipeline embolization of an incidental right paraophthalmic artery aneurysm and suffered distal embolization of the radiopaque marker from a distal guide catheter (088 Neuron Max, Penumbra, Alameda, California, USA) used during neuroendovascular intervention. To the best of our knowledge, this is the first reported case of distal embolism from an unprovoked fracture of a neurointerventional catheter. Conclusions Knowledge of several salvage techniques is essential in preventing major cerebrovascular complications. It is imperative that a multilevel approach should be taken when treating foreign body embolism. [ABSTRACT FROM AUTHOR]