Improving the Prognosis of Patients With Acute Ischemic Stroke Treated in the Late Time Window After the Introduction of Advanced Imaging Software: Benefits From Thrombectomy in the Extended Time Window.

BACKGROUND: Mechanical thrombectomy (MT) of ischemic stroke was recommended as a clinical guideline in 2015, and the indication for time was expanded in 2018 based on two clinical studies. We aimed to compare and analyze the prognosis of patients treated under the extended time indication before and after the introduction of advanced software. METHODS: We obtained data from medical records between 2016 to 2020. From 2016 to 2017, patients who did not receive MT who visited the hospital within 24 hours from the last normal time (LNT) were classified as standard medical treatment (SMT) group. Among patients who underwent MT between 2019 and 2020, patients who visited the hospital between 6-24 hours from the LNT were classified into the extended MT (EMT) group. Good outcome was defined as 3-months modified rankin scale (mRS) ≤ 2, and a poor outcome as mRS ≥ 4. RESULTS: From 2016 to 2017, 1,058 patients were hospitalized for ischemic stroke, of which 60 (5.7%) received MT, and 27 patients were classified into the SMT group. Among 1,019 patients between 2019 and 2020, 85 (8.3%) received MT, and 24 patients were in the EMT group. Among the SMT group, only 3 had a good prognosis, and 24 (88.9%) had a poor prognosis. However, in the EMT group, 10 (41.7%) had a good prognosis, and 9 (37.5%) had a poor prognosis. The SMT group had a 49.1 times higher risk of poor prognosis compared to the EMT group (P = 0.008). CONCLUSION: The number of patients with ischemic stroke who receive MT has increased by using advanced imaging software. It was confirmed that patients treated based on the extended time indication also had a good prognosis.

A deep learning algorithm may automate intracranial aneurysm detection on MR angiography with high diagnostic performance.

OBJECTIVES: To develop a deep learning algorithm for automated detection and localization of intracranial aneurysms on time-of-flight MR angiography and evaluate its diagnostic performance. METHODS: In a retrospective and multicenter study, MR images with aneurysms based on radiological reports were extracted. The examinations were randomly divided into two data sets: training set of 468 examinations and internal test set of 120 examinations. Additionally, 50 examinations without aneurysms were randomly selected and added to the internal test set. External test data set consisted of 56 examinations with intracranial aneurysms and 50 examinations without aneurysms, which were extracted based on radiological reports from a different institution. After manual ground truth segmentation of aneurysms, a deep learning algorithm based on 3D ResNet architecture was established with the training set. Its sensitivity, positive predictive value, and specificity were evaluated in the internal and external test sets. RESULTS: MR images included 551 aneurysms (mean diameter, 4.17 ± 2.49 mm) in the training, 147 aneurysms (mean diameter, 3.98 ± 2.11 mm) in the internal test, 63 aneurysms (mean diameter, 3.23 ± 1.69 mm) in the external test sets. The sensitivity, the positive predictive value, and the specificity were 87.1%, 92.8%, and 92.0% for the internal test set and 85.7%, 91.5%, and 98.0% for the external test set, respectively. CONCLUSION: A deep learning algorithm detected intracranial aneurysms with a high diagnostic performance which was validated using external data set. KEY POINTS: • A deep learning-based algorithm for the automated diagnosis of intracranial aneurysms demonstrated a high sensitivity, positive predictive value, and specificity. • The high diagnostic performance of the algorithm was validated using external test data set from a different institution with a different scanner. • The algorithm might be robust and effective for general use in real clinical settings.

Sudden sensorineural hearing loss with intralabyrinthine hemorrhage after COVID-19 vaccination.

Otologic symptoms of sudden sensorineural hearing loss (SSNHL) have been reported after Coronavirus disease 2019 (COVID-19) vaccinations. However, the association between SSNHL and COVID-19 vaccination has not been clearly established. SSNHL with vertigo can be induced by intralabyrinthine hemorrhage (ILH). The case of a 61-year-old female who was diagnosed SSNHL with ILH after COVID-19 vaccination is presented here. She visited the emergency department for left sudden hearing loss and vertigo that had occurred the previous day. She had received a third booster COVID-19 mRNA vaccination one day prior to the visit; symptoms occurred 6 hours after vaccination. On pure tone audiometry, her hearing threshold indicated deafness in the left ear. A lesion assumed to be ILH was observed on temporal magnetic resonance imaging. She received an oral steroid followed by salvage treatment with intratympanic steroid injection. Three months after symptom onset, her hearing threshold remained deaf with slight improvement at low frequencies in the left ear. Because the symptoms of and prognosis for SSNHL may be worse and vertigo may occur in patients with SSNHL and ILH, careful treatment is required.

Rescue microsurgery in coil herniation causing thromboembolic occlusion of parent artery.

BACKGROUND: Malpositioned coils can provoke abrupt occlusion of the parent vessels and/or neighboring branches causing stroke during coil embolization (CE) of intracranial aneurysms. The authors describe a series of cases in which urgent surgical recanalization of the vessels clogged with herniated or migrated coils rescued the patients. METHODS: A total of six patients with aneurysms who underwent surgical management for parent artery occlusion linked with inadvertent coil herniation were selected. Their medical-surgical records and operative video recordings were reviewed retrospectively. RESULTS: There were five females and one male whose ages ranged from 44 to 59 years. Occluded vessels associated with CE were three A2 segments of the anterior cerebral artery (ACA), two M2 segments of the middle cerebral artery (MCA) and one superior cerebellar artery (SCA). Surgical management included securing control of both the proximal and distal parent artery, making small openings, safe removal of coils, thorough cleaning of debris and thrombus, and subsequent closure of the opening, which was successful in five of patients and resulted in excellent clinical outcome. However, in the SCA case, surgical retrieval of coils failed due to technical difficulties and yielded untoward results. CONCLUSIONS: This report demonstrates that timely surgical intervention could be considered as a safe and effective option to solve serious thromboembolic complications of CE associated with herniated coils.

Blister-like aneurysms of the supraclinoid internal carotid artery: challenging endovascular treatment with stent-assisted coiling.

''Blister-like'' aneurysms of the supraclinoid segment of the internal carotid artery are usually small and have fragile walls, necessitating special care to prevent rebleeding. These lesions are considered high-risk aneurysms because of the technical difficulties associated with their surgical and endovascular treatment. In this report, we describe the use of stent-assisted, repeated coil embolization in the treatment of a ruptured blister-like aneurysm that experienced rapid growth. Stent-assisted coil embolization is an alternative, but sometimes hazardous, treatment for select blister-like aneurysms. Careful serial follow-up angiography will provide documentation as to the long-term stability of the endovascularly treated blister-like aneurysm described here, but early results are encouraging. Alternatively, placement of telescoped stents or graft-stent devices offers promise for future endovascular therapy.

Dual microcatheter coil embolization of acutely ruptured wide-necked intracranial aneurysms.

The dual microcatheter technique is an alternative treatment for stent-assisted coiling in acutely ruptured wide-necked aneurysms because of no antiplatelet therapy. We assessed the safety and efficacy of this technique in ruptured wide-necked aneurysms. Between March 2008 and March 2016, 56 acutely ruptured aneurysms were treated with the dual microcatheter technique. The angiographic results, treatment-related complications, and clinical outcome were documented. Angiographic follow-up was available in 37 patients at a mean of 20.6 months (6 to 81 months). On the postembolization angiograms, 27 (48.2%) aneurysms showed complete occlusion (Raymond 1), 15 (26.8%) showed neck remnant (Raymond 2), and 14 (25.0%) showed body remnant (Raymond 3). Treatment-related complications occurred in seven patients (12.5%) and six patients remained asymptomatic. The permanent complication rate was 1.8% (1/56). A good outcome (modified Rankin Scale (mRS) score, 0-2) was observed in 64.3% of patients at the time of discharge. Five patients had died, all of the sequelae of subarachnoid hemorrhage. The overall mortality rate was 8.9% (5/56); however, the treatment-related mortality rate was 0%. Of the 37 aneurysms for which angiographic follow-up was available, 21 (56.8%) aneurysms demonstrated recanalization. Five aneurysms with recanalization were retreated endovascularly. There was one aneurysm re-rupture on follow-up and it rebled 21 months after the initial procedure. The dual microcatheter technique is a safe and effective treatment for acutely ruptured wide-necked aneurysms due to low treatment-related complication and mortality rate. However, the high rate of postembolization incomplete occlusion and recanalization remains as the main challenge.

Endovascular thrombolysis and stenting of a middle cerebral artery occlusion beyond 6 hours post-attack: special reference to the usefulness of diffusion-perfusion MRI.

Intra-arterial thrombolysis and percutaneous angioplasty is feasible in patients with acute middle cerebral artery (MCA) occlusion limited to 6 hours post-ictus, but there are some limitations such as reocclusion or hemorrhagic complications. In this report, we describe a stent placement in the treatment of a refractory artherothrombotic MCA occlusion beyond 6 hours of symptom onset. A 57-year-old man presented with a progressive left-sided weakness and verbal disturbance resulting from an acute thrombotic occlusion of the right MCA superimposed on severe proximal atheromatous stenosis. Diffusion-perfusion magnetic resonance imaging (MRI) demonstrated the significant diffusion-perfusion mismatch. After chemical and mechanical thrombolysis of the clot, balloon angioplasty of the underlying MCA stenosis was performed 2 days post-attack, without significant angiographic improvement. Percutaneous endovascular deployment of a stent (Driver 2.5 x 12 mm, MTI, Irvine, CA) was subsequently performed, with excellent angiographic results. Follow-up diffusion-perfusion MRI showed improved perfusion in the hypoperfused area. The patient's National Institutes of Health Stroke Scale (NIHSS) score was increased from 12 to 3. Clot thrombolysis and subsequent stenting in patients with refractory proximal MCA occlusion is feasible and allows for a significant reduction in the amount of thrombolytic drug required. In selective patients with acute MCA occlusion, the therapeutic window for recanalization procedures can be safely and effectively extended beyond the 'traditional 6 hours'. Diffusion-perfusion MRI in acute MCA occlusion is important for indication of therapy.

Solitary Fibrous Tumor of Central Nervous System: A Case Report.

Solitary fibrous tumor (SFT) is a rare neoplasm of mesenchymal origin, especially in the central nervous system (CNS). Reported herein is a case of SFT of CNS in a 63-year-old female patient who had confused mentality, without other neurological deficit. The brain MRI showed an ovoid mass in the right frontal lobe. The tumor was surgically removed grossly and totally, and the pathologic diagnosis was SFT. At 55 months after the surgery, the tumor recurred at the primary site and at an adjacent area. A second operation was thus done, and the tumor was again surgically removed grossly and totally. The pathologic diagnosis was the same as the previous, but the Ki-67 index was elevated. Ten months later, two small recurring tumors in the right frontal skull base were found in the follow-up MRI. It was decided that radiation therapy be done, and MRI was done again 3 months later. In the follow-up MRI, the size of the recurring mass was found to have decreased, and the patient did not manifest any significant symptom. Follow-up will again be done 18 months after the second surgery.

The olfactory groove schwannoma attached to the cribriform plate: a case report.

The olfactory groove schwannoma is a quite rare tumor. We report a case of a 49-year-old woman with an olfactory groove schwannoma attached to the cribriform plate without olfactory dysfunction. She had no specific neurological symptoms other than a headache, and resection of the tumor showed it to be a schwannoma. About 19 months after the operation, a follow-up MRI showed no evidence of tumor recurrence. Surgical resection through subfrontal approach could be one of the curative modality in managing an olfactory groove schwannoma. An olfactory groove schwannoma should be considered in the differential diagnosis of anterior skull base tumors.

Traumatic dissection of the internal maxillary artery associated with isolated glossopharyngeal nerve palsy: case report.

OBJECTIVE AND IMPORTANCE: Spontaneous or traumatic dissection of the internal carotid artery with resultant lower cranial nerve palsies is well documented. However, dissection of the external carotid artery with lower cranial palsies has not been reported previously. CLINICAL PRESENTATION: A 42-year-old man experienced an epidural hematoma as the result of a fall and underwent a craniotomy and hematoma removal. Subsequently, he developed dysgeusia and difficulty in swallowing. Brain magnetic resonance imaging showed a dilated linear structure, with isosignal intensity on T1-weighted images and hyperintense signal intensity on T2-weighted images. Strong enhancement was seen on postcontrast T1-weighted images, indicating a dissected internal maxillary artery. This was confirmed on selective angiography of the left common carotid artery. INTERVENTION: Guglielmi detachable coils were introduced into the false lumen of the dissected artery. Subsequently, 0.5 ml of glue mixed with Lipiodol (Lafayette Pharmacal, Lafayette, IN) was packed into the remnant of the false lumen. Repeat angiograms demonstrated complete occlusion of the dissected vessel. The patient's postoperative course was uneventful, and the neurological deficits gradually improved. CONCLUSION: We describe the first reported case of internal maxillary artery dissection and pseudoaneurysm presenting with isolated glossopharyngeal nerve palsy. The association between cranial nerve palsy and dissection of the external carotid artery branch may be the result of a compressive mechanism, as suggested by its anatomic relationships, the characteristics of the dissection, and the good prognosis. Endovascular embolization of the external carotid artery dissection and pseudoaneurysm is suggested as an effective therapeutic method for improving or alleviating neurological deficits produced by mass effect.

Emergency endovascular treatment of internal carotid artery injury during a transsphenoidal approach for a pituitary tumor --case report--.

Carotid artery injury is a very rare, but life threatening complication that can occur during a transsphenoidal approach. We experienced one case of carotid artery injury during a transsphenoidal pituitary tumor surgery. The patient was immediately treated by a balloon occlusion and complete packing of the cavernous carotid artery using Guglielmi detachable coils (GDCs) and the rest of the tumor was removed after the carotid occlusion. The patient recovered without showing any neurological deficits.

Significance of 99mTc-ECD SPECT in acute and subacute ischemic stroke: comparison with MR images including diffusion and perfusion weighted images.

99mTc-ECD SPECT is valuable for the evaluation of cell viability and function. The purpose of the present study was to evaluate the significance of 99mTc-ECD brain SPECT in ischemic stroke. We compared 99mTc-ECD brain SPECT with perfusion and diffusion weighted images (PWI, DWI). Ten patients with acute and early subacute ischemic stroke were included in this prospective study. T2-weighted images (T2WI), DWI, PWI and 99mTc-ECD SPECT were obtained during both the acute/early subacute and late subacute stages. In the case of PWI, time to peak (TTP) and regional cerebral blood volume (rCBV) maps were obtained. The rCBV map and 99mTc-ECD SPECT images were compared in 8 lesions using DeltaAI. The asymmetry index (AI) was calculated as (Ci - Cc) X 200 / (Ci + Cc); where Ci is the mean number of pixel counts of an ipsilateral lesion and Cc is the mean number of pixel counts of the normal contralateral hemisphere. DeltaAI was defined as AIacute - AIsubacute in the ischemic core and periphery. PWI and 99mTc-ECD SPECT detected new lesions of the hyperacute stage or of evolving stroke more accurately than T2WI and DWI. 99mTc-ECD SPECT was able to localize the infarct core and peri-infarct ischemia in all lesions in both the acute and the subacute stages. DeltaAI was higher in the rCBV map than in the 99mTc-ECD SPECT images in the ischemic core (p = 0.063) and in the periphery (p = 0.091). In the 99mTc-ECD SPECT images, DeltaAI was higher in the ischemic core than in the periphery (p = 0.028). During the subacute stage, 99mTc-ECD SPECT detected all the lesions without the pseudonormalization seen in the MR images of 5/11 lesions. Based on this study, 99mTc-ECD SPECT is comparable to PWI in terms of its ability to detect acute stroke and is more useful than PWI in the case of subacute infarction.

Transvenous Embolization of Cavernous and Paracavernous Dural Arteriovenous Fistula through the Facial Vein: Report of 12 Cases.

PURPOSE: The aim of this study was to evaluate the feasibility and safety of the transfacial venous embolization of cavernous or paracavernous dural arteriovenous fistula (DAVF) in which approach via inferior petrosal sinus (IPS) was not feasible. MATERIALS AND METHODS: We identified the cases of transfacial venous embolization of cavernous sinus (CS) or adjacent dural sinuses from the neurointerventional database of three hospitals. The causes and clinical and angiographic outcomes of transfacial venous embolization were retrospectively evaluated. RESULTS: Twelve patients with CS (n = 11) or lesser wing of sphenoid sinus (LWSS, n = 1) DAVF were attempted to treat by transvenous embolization via ipsilateral (n = 10) or contralateral (n = 2) facial vein. Trans-IPS access to the target lesion was impossible due to chronic occlusion (n = 11) or acute angulation adjacent the target lesion (n = 1). In all twelve cases, it was possible to navigate through facial vein, angular vein, superior ophthalmic vein, and then CS. It was also possible to further navigation to contralateral CS through intercavernous sinus in two cases, and laterally into LWSS in one case. Post-treatment control angiography revealed complete occlusion of the DAVF in eleven cases and partial occlusion in one patient, resulting in complete resolution of presenting symptom in eight and gradually clinical improvement in four patients. There was no treatment-related complication during or after the procedure. CONCLUSION: In the cavernous or paracavernous DAVF in which trans-IPS approach is not feasible, the facial vein seems to be safe and effective alternative route for transvenous embolization.

Posttraumatic infarction in the territory supplied by the lateral lenticulostriate artery after minor head injury.

BACKGROUND: Occlusion of the intracranial arteries due to blunt head traumas has been less frequently observed in patients with minor head injuries. CASE REPORT: A 4-year-old boy presented with speech disturbance 2 h after minor head injury. An initial computed tomography (CT) scan showed a questionable finding of a focal punctate high density in the left basal ganglia. Hemiparesis developed on the right limbs 8 h post-injury, and a subsequent CT scan revealed a discrete low-density change around the focal high density. Diffusion-weighted images revealed a clearly demarcated high-signal intensity lesion in similar area on T2-weighted and fluid-attenuated inversion recovery sequences images, compatible with infarcted tissues on the territory supplied by the lateral lenticulostriate artery. His hemiparesis improved gradually, and by post-trauma day 10 he was able to walk briefly without assistance. He was discharged on foot at post-trauma day 14. DISCUSSION AND CONCLUSION: Children with minor head trauma who have normal findings on initial CT scan may rarely have basal ganglionic infarction resulting from arterial spasm or thromboembolism of the perforating arteries. Hospital admission and careful observation should be considered for patients with minor head injury and persistent neurologic deficits despite normal CT findings. Magnetic resonance study is valuable for the evaluation of posttraumatic infarction, differentiating from hemorrhagic diffuse axonal injuries.

Parapharyngeal branchial cleft cyst extending to the skull base: a lateral transzygomatic-transtemporal approach to the parapharyngeal space.

Second branchial cleft cysts (BCCs) can occur anywhere from the tonsillar fossa to the supraclavicular area. Second BCCs usually lie on the great vessels of the neck, deep in the sternocleoidomastoid muscle or along its anterior border at the mandibular angle. Parapharyngeal second BCCs are an uncommon neoplasm and rarely extend to the skull base. We report the case of a 45-year-old male with symptoms of conductive hearing loss. Temporal bone CT scan showed effusion in the left middle ear cavity. Magnetic resonance imaging (MRI) revealed a cystic mass that was located at the left parapharyngeal space and eroded the skull table of the left temporal base. Excision of the lesion was achieved via a transzygomatic-transtemporal approach to the parapharyngeal space. Histopathological examination of the cyst wall showed a single layer of ciliated columnar epithelium without goblet cells or lymphoid tissue. The patient recovered without any complications and experienced complete resolution of left-sided hearing difficulty. We conclude the lateral transzygomatic-transtemporal approach allows surgeons direct access to the parapharyngeal space with satisfactory exposure for treating benign lesions of the parapharyngeal space.

Treatment of intra- and extracranial arterial dissections using stents and embolization.

PURPOSE: To evaluate the safety and efficacy of stent placement for extracranial and intracranial arterial dissections. METHODS: Eighteen patients underwent endovascular treatment of carotid and vertebral dissections using intraluminal stent placement. Five patients with arterial dissection were treated, 2 using one insertion of a single stent and 3 using placement of two stents. Patients with a dissecting aneurysm were treated as follows: 7 patients with insertion of one stent, 4 with placement of two stents, and 2 by stent-assisted Guglielmi detachable coil embolization. In the 18 patients in whom stenting was attempted, the overall success in reaching the target lesion was 94.4%. Of the 17 patients treated with stents, stent release and positioning were considered optimal in 16 (94%) and suboptimal in one (6%). In patients who underwent a successful procedure, all parent arteries were preserved. There were no instances of postprocedural ischemic attacks, new neurologic deficits, or new minor or major strokes prior to patient discharge. In follow up, all patients were assessed, using the modified Rankin scale, as functionally improved or of stable clinical status. The reduction in dissection-induced stenosis or pseudoaneurysm, the patency rate obtained at follow-up, and the lack of strokes (ischemic or hemorrhagic) suggest that stent placement offers a viable alternative to complex surgical bypass or reconstructive procedures. The long-term efficacy and durability of stent placement for arterial dissection remain to be determined in a larger series.

Therapeutic endovascular treatments for traumatic carotid artery injuries.

OBJECTIVE: The diagnosis and management of traumatic carotid vessel injuries continue to be controversial, with direct surgical repair with parent artery preservation still presenting difficulties. The purpose of this report is to review the endovascular therapy of patients with traumatic carotid vessel injuries for preservation of the parent artery, and to determine the safety and efficacy of endovascular therapy. METHODS: Ten patients with traumatic carotid lesions were treated using therapeutic endovascular methods. Endovascular therapy was accomplished by implanting balloons, porous or polytetrafluoroethylene-covered stents, and/or embolic materials including coils or glue. RESULTS: All fistulas and pseudoaneurysms were successfully embolized with no periprocedural complications including vessel disruption/rupture, distal embolization, or new neurologic deficits. The parent arteries of all patients except one were preserved. The reason for the parent artery sacrifice was a thrombus formation due to coil migration into the parent artery. No additional surgical procedures for vascular lesions were required. There were no delayed neurologic or vascular complications, and no lesions recurred during the follow-up periods (mean 20.3 months). CONCLUSION: The goal of endovascular therapy is the selective elimination of the vascular pathology with the normal patency of the cerebral arteries. The authors' experience demonstrates that endovascular therapy using stents, balloons, and coils is both feasible and safe for treatment of traumatic carotid injuries. Of these endovascular methods, the stent can be used to exclude the aneurysm or fistula from the circulation and preserve the parent artery in selective cases. Long-term follow-up review of these repairs will be necessary to provide a full evaluation of the safety and efficacy of these devices.