Traumatic arteriovenous fistula of the middle meningeal artery treated with selective coil embolization: A case report.

Background: Dural arteriovenous fistulas (AVFs) are reportedly induced by trauma. We report a rare case of traumatic AVF with a direct shunt from the middle meningeal artery (MMA) to the middle meningeal vein (MMV) and multiple drainage routes after head trauma. The patient was effectively treated with selective coil embolization alone without liquid embolic material. Case Description: A 56-year-old woman was admitted to the emergency department with mild disturbance of consciousness caused by a head contusion after alcohol consumption. She exhibited impaired consciousness with a Glasgow coma scale score of 14 (E4V4M6), complained of headache, and presented with a hemorrhage in the left ear. Computed tomography suggested a skull fracture and cerebral hemorrhage. Magnetic resonance imaging conducted on the 4th day after the injury indicated shunt disease with a feeder in the right MMA. Cerebral angiography on the 7th day suggested a direct shunt from the right MMA to the MMV aligned with the temporal bone fracture line, with multiple drainage route perfusion. Coil embolization was performed on the 14th day to occlude the shunt point selectively. In the final image, the MMA was absent, and the MMV, superior sagittal sinus, or pterygoid plexus was not visible through the shunt. Her symptoms improved, and she was discharged on the 20th day and did not exhibit recurrence at the 1-year follow-up. Conclusion: AVF with a direct shunt from the MMA to MMV after head trauma can be effectively and safely treated with coil embolization alone, despite the need for long-term postoperative follow-up.

Intracranial Non-Sinus-Type Dural Arteriovenous Fistulas Could Be Curable by Transarterial Embolization or Transvenous Embolization with Liquid Embolic Material.

Objective: Recently, the occlusion rate of transarterial embolization (TAE) for intracranial non-sinus-type dural arteriovenous fistulas (NSDAVFs) has improved after ONYX was introduced. Additionally, when TAE for NSDAVF is unsuccessful, transvenous embolization (TVE) has become available as an alternative treatment. We investigated the factor for the favorable occlusion rate of endovascular treatment for NSDAVF at our institutions. Methods: Two hundred and twenty-seven patients with intracranial dural arteriovenous fistulas (DAVFs) were treated at our institutions between September 2014 and October 2022. The patients diagnosed with NSDAVF in all DAVFs who underwent endovascular treatment were included. The clinical characteristics, angiographical outcomes, and clinical outcomes of patients who underwent endovascular treatment were evaluated. Results: Thirty-eight patients had intracranial NSDAVF (tentorial: 23 cases, parasagittal-convexity: 7, anterior cranial fossa: 6, middle cranial fossa: 2). Our participants' mean age was 64.8 ± 11.3 years, and 31 (81.6%) of them were males. Patients' symptoms were as follows: asymptomatic (24), hemorrhage (10), tinnitus (3), and trigeminal neuralgia (1). TAE and TVE were performed on 35 and 3 patients, respectively. The rate of immediate angiographical occlusion was 84.2% (32/38). The follow-up angiographical occlusion rate in 6 months was 88.5% (31/35). Complications occurred in three cases. There was no morbidity or mortality after 30 days. Conclusion: TAE using the combination of the new microcatheter and microguidewire and TVE in the case of difficult or failed TAE for NSDAVF could achieve high success rates and safety.

[Comparison of Bayesian Estimation and SVD Methods for CT Perfusion in Patients with Acute Stroke].

PURPOSE: There are various analysis methods for CT perfusion (CTP). Although the advantages of Bayesian estimation algorithms have been newly suggested, comparisons with other analysis methods on clinical data are still limited. In this study, we compared the Bayesian estimation method with the singular value decomposition (SVD) method in the evaluation of patients with acute cerebral infarction and examined its usefulness. METHODS: CTP data from 13 patients with acute stroke were analyzed using the SVD and Bayesian estimation methods implemented in Vitrea. Evaluation of visual clarity of the ischemic area and quantitative values of the healthy side-affected side ratio using the mean values of the left and right region of interest (ROI) on the images were compared using the SVD and Bayesian estimation methods. RESULTS: In visual evaluation, there were significant differences in CBV in four cases, and in CBF, MTT, and TTP in many cases. The healthy side-affected side ratio of the SVD and Bayesian estimation methods were as follows: CBF 1.19, 1.84; CBV 1.09, 1.02; MTT 1.12, 1.79; and TTP 1.48, 1.19. For CBF and MTT, the Bayesian estimation method had a larger ratio of the healthy side to the affected side, and for TTP, the SVD method had a larger ratio of the test side to the affected side. CONCLUSION: We suggest that the Bayesian estimation method is more useful than the SVD method for assessing CBF and MTT in CTP analysis of patients with acute stroke.

Delayed rupture of a large intracranial internal carotid artery aneurysm after flow diverter placement.

Background: Delayed rupture after flow diverter (FD) placement is a serious complication, and often it leads to death; however, the exact mechanism leading to the rupture remains unclear. Therefore, in this case, study, we report a case of delayed rupture after FD placement and discuss its causes. Case Description: This study presents the case of a 69-year-old female with multiple aneurysms who underwent FD placement with coil embolization for a large intracranial internal carotid artery aneurysm. Postoperatively, the patient had no significant symptoms, and angiography and magnetic resonance imaging revealed decreased intra-aneurysmal blood flow. However, on the 3rd postoperative day, she developed a sudden disturbance of consciousness. Computed tomography revealed a massive subarachnoid hemorrhage, diagnosed as a delayed rupture. We decided to withhold therapy due to her serious condition. Previous studies have suggested that hemodynamic mechanisms can cause delayed aneurysm rupture. Based on the computational fluid dynamics (CFD) of the aneurysm, we suggest that an increase in intra-aneurysmal pressure after FD placement may have caused the delayed rupture. Conclusion: Preoperative CFD analysis may help evaluate the risk of delayed rupture for large aneurysms with a high inflow from the parent vessel.

A Case of De Novo Basilar Artery Aneurysm Associated with Proximal Stenosis Treated by Coil Embolization.

Objective: This report highlights a case of a de novo aneurysm assumed to be caused by hemodynamic stress resulting from proximal basilar artery stenosis. Case Presentation: A 76-year-old woman presented at our hospital with tinnitus. Although MRI did not reveal the cause of her tinnitus, it did uncover an incidental finding of basilar artery stenosis. The patient reported a history of cerebral infarction, diabetes, and hypertension. Six years following the initial discovery of basilar artery stenosis, a saccular aneurysm was detected at the bifurcation of the basilar artery and the right anterior inferior cerebellar artery, corresponding to the distal portion of the basilar artery stenosis. Upon revelation of an enlarged aneurysm on the subsequent two-year follow-up MRI, the patient received coil embolization treatment. No signs of recurrence were observed on the next two-year follow-up MRI. Conclusion: It was assumed that proximal basilar artery arteriosclerotic stenosis had caused hemodynamic stress on the distal vessel wall, and that this was responsible for the formation and growth of a de novo aneurysm. This case suggests that cerebrovascular arteriosclerotic changes may be associated with de novo aneurysm formation and therefore requires careful follow-up.

Endovascular Treatment for Dural Arteriovenous Fistulae Using a Sinus Protection Balloon to Maintain the Patency of the Dural Sinus.

We introduce our technique to treat dural arteriovenous fistulae (dAVFe) under sinus balloon protection. The Kaneka Shoryu 7 × 7 mm balloon was used for sinus occlusion. Initially, the balloon was inflated slowly using 1.5-2.0 mL of saline on the table. A 6F guiding catheter was navigated into the proximal portion of the lesion from the jugular vein of the affected side. The balloon catheter was introduced to the point occluding the shunt. The balloon was temporarily inflated to determine the occlusion point without occluding the outlet of the vein of Labbe. ONYX injection was started from the microcatheter located at just proximal to the shunt point under sinus balloon occlusion. ONYX penetrated the feeding arteries in an antegrade and retrograde manner. After the penetration of ONYX into each feeding artery, the inflated balloon was temporarily deflated to examine the residual shunt. If a small shunt remained, the balloon was inflated again and ONYX injection was continued. To cure dAVF, the location of the balloon is important. The guiding catheter should be placed just proximal to the shunt and the balloon catheter should be gently pulled to stabilize the balloon position.

[A Case of Erdheim-Chester Disease that was Difficult to Differentiate from Meningioma].

OBJECTIVE: Erdheim-Chester disease(ECD)is a rare type of non-Langerhans histiocytosis. We report a surgical case of ECD with multiple lesions at the falx cerebri, tentorium cerebelli, and in the suprasellar region, with a literature review. CASE REPORT: A 70-year-old woman presented with frequent falling and difficulty in standing. Her past medical history revealed ovarian cystectomy, transient thrombocytopenia, hypertension, left lower leg pain, and overactive bladder. Her head CT and MRI findings revealed well-defined mass lesions, suspected of meningioma, at the falx cerebri and tentorium cerebelli. Craniotomy and near total resection of the tumor at the falx cerebri was performed, leaving a hard portion of the tumor on the right falx. Intraoperative findings showed a solid and hard tumor, which was extremely difficult to decompress. Although the histopathological diagnosis was originally a metaplastic meningioma, considering her complaints of lower leg pain, we suspected ECD and performed a right tibial biopsy. The right tibial biopsy revealed ECD. Twenty-two months after the operation, the patient exhibited a marked enlargement of the tentorium lesion and a new lesion in the suprasellar region. Resection of the tentorial lesion was performed. The second intraoperative findings were similar to those of the first. The histopathological diagnosis of the tentorial lesion was ECD. After the surgeries, steroid therapy and radiation therapy were performed, but only with temporary improvement. CONCLUSION: ECD is a rare disease; therefore, accumulation of clinical data to establish its treatment is necessary.

Intraosseous Arteriovenous Fistula Around the Anterior Condylar Confluence as an Occipital Bone Fracture Sequela.

BACKGROUND: Although traumatic dural arteriovenous fistula (AVF) is a rare condition, dural injury associated with skull fracture is one of the major factors for the formation of dural AVF at the skull fracture area. We report a case of de novo intraosseous AVF around the anterior condylar confluence after head injury associated with skull base fracture. CASE DESCRIPTION: A woman in her 70s presented with pulsatile tinnitus 3 months after cerebellar infarction and occipital bone fracture. The appearance of de novo intraosseous AVF was confirmed by magnetic resonance imaging and magnetic resonance angiography and treated with coil embolization, which led to symptomatic relief without recurrence on follow-up. CONCLUSIONS: There is no previous report to our knowledge of intraosseous AVF around the anterior condylar confluence proven to appear after skull fracture. This case demonstrates that head injury associated with skull base fracture could be one etiology of dural AVF around the anterior condylar confluence.

A Case of Anterior Cranial Fossa Dural Arteriovenous Fistula with Transient Ocular Movement Disorder after Embolization.

Objective: We report a case of anterior cranial fossa dural arteriovenous fistula (dAVF) in which ocular movement was impaired after Onyx embolization from the ophthalmic artery (OphA). Case Presentation: A 76-year-old male was admitted to our hospital for treatment of an incidentally found anterior cranial fossa dAVF. Onyx was injected from the right anterior ethmoidal artery (AEA) to close the shunt. Onyx refluxed to the third portion of the OphA to make a plug, but was unable to reach the venous side beyond the shunt; therefore, a small shunt remained. Although his visual acuity and field were normal, vertical diplopia developed after embolization and disappeared 1 month later. Diplopia worsened when the patient tilted his head to the right. Neuro-ophthalmological examination confirmed right superior oblique muscle impairment. The cause of diplopia was considered to be ischemic injury of the superior oblique muscle associated with embolization of the AEA, which provides nutrients to the superior oblique muscle and trochlear nerve. Conclusion: Embolization from the OphA beyond the third portion may cause external ophthalmoplegia, although it may heal spontaneously.

[Transvenous Embolization by Direct Puncture of the Superior Sagittal Sinus Using Indocyanine Green(ICG)Videoangiography for Treatment of Dural Arteriovenous Fistula of the Transverse-Sigmoid Sinus:A Case Report].

We report a case of dural arteriovenous fistula at the left transverse sinus and sigmoid sinus(TS-dAVF), which was treated with transvenous embolization(TVE)by direct puncture of the superior sagittal sinus(SSS)under indocyanine green(ICG)fluoroscopic guidance. A 71-year-old woman presented with pulsatile tinnitus and progressive dementia. A left TS-dAVF with retrograde SSS and cortical venous reflux(Cognard type IIb)was demonstrated on cerebral angiography. The left internal jugular vein and distal portion of the right transverse sinus were occluded. We considered that TVE via the femoral vein would be difficult for complete cure. We performed trepanation of the frontal portion of the SSS. The SSS was directly punctured with an 18-G needle under ICG fluoroscopic guidance. We inserted a 4-Fr sheath into the SSS. A microcatheter was navigated into the affected sinus. Coils were placed through the microcatheter. The dAVF was completely diminished. No complications occurred. The patient's pulsatile tinnitus disappeared and dementia improved. Transvenous approach with direct puncture of the SSS under ICG fluoroscopic guidance was a useful approach for the treatment of dAVF when other approaches were difficult.

Ipsilateral hemiparesis in lateral medullary infarction: Clinical investigation of the lesion location on magnetic resonance imaging.

BACKGROUND: In 1946, Opalski reported two cases of Wallenberg syndrome with ipsilateral hemiparesis (IH). His hypothesis seems to be based on the view that IH is caused by post-decussating pyramidal tract damage. Afterwards, other researchers proposed a different hypothesis that ipsilateral sensory symptoms of limbs (ISSL) or ipsilateral limb ataxia (ILA) caused by lateral medullary infarction (LMI) might lead to ipsilateral motor weakness. The present study is aimed to clarify whether IH in LMI patients is attributable mainly to ISSL/ILA or disruption of ipsilateral post-decussating pyramidal tract. METHODS: Thirty-two patients with acute LMI admitted during the last 13years were divided to IH Group (n=7) and Non-IH Group (n=25). Lesion location/distribution on MRI and neurological findings were compared between the two groups. RESULTS: LMI involved the lower medulla in all seven IH patients and 12 of 25 Non-IH patients. The lower medullary lesion extended to the cervico-medullary junction (CMJ) in four of seven IH patients and one of 12 Non-IH patients. Definitive extension to upper cervical cord (UCC) was confirmed in none of the patients. ISSL was found in two IH and three Non-IH patients all showing only superficial sensory impairments. ILA or hypotonia was observed in 57% of IH and 60% of Non-IH patients. CONCLUSION: IH in LMI appears to be due mainly to post-decussating pyramidal tract damage at the lower medulla instead of ILA or ISSL participation.

Detectability of ischemic lesions on diffusion-weighted imaging is biphasic after transient ischemic attack.

BACKGROUND: Experimental studies of transient focal ischemia indicate biphasic detectability of lesions by diffusion-weighted imaging (DWI); poorly detectable phase exists at 1-12 hours after reperfusion. The present study aimed to clarify whether poorly detectable phase also exists in DWI of transient ischemic attack (TIA) patients. METHODS: A retrospective study was conducted in 144 consecutive TIA patients who underwent magnetic resonance imaging (MRI) within 2 weeks after carotid TIA. Patients were classified into 9 groups according to time from disappearance of TIA symptoms to DWI: intraischemic period, 0-1 hour, 1-12 hours, 12-24 hours, 1-2 days, 2-3 days, 3-7 days, 7-10 days, and 10-14 days after the end of TIA. RESULTS: Lesions were detected in 33 of 144 patients (22.9%). The frequency of positive lesions was 20% in the intraischemic period and 30.8% at 0-1 hour after the end of TIA; it markedly decreased to 8.7% at 1-12 hours after end of TIA. Thereafter, it increased to 21.7%, 30.8%, 36.4%, 37.0%, 38.5%, and 30% at 12-24 hours, 1-2 days, 2-3 days, 3-7 days, 7-10 days, and 10-14 days after the end of TIA, respectively. In 7 patients, MRI was repeated twice, at 1-12 hours and then at 5-13 days after the end of TIA. Lesions were never detected on the first MRI but were clearly demonstrated in 4 of 7 patients on the second MRI. CONCLUSIONS: The detectability of ischemic lesions may be biphasic after TIA as indicated by experimental studies.

Severe and prolonged ictal paresis in an elderly patient.

We report an 84-year-old female who showed a rare manifestation of epilepsy, ictal paresis, a type of simple partial seizure presenting with focal motor dysfunction. While the patient exhibited severe left hemiplegia which lasted for a week, cranial diffusion-weighted MRI demonstrated slightly high intensity in the right posterior quadrant, and electroencephalography (EEG) showed continuous epileptiform discharges located mainly in the right parieto-occipital area, strongly suggesting that the patient was in an ictal state. (99m)Tc-hexamethylpropylene amine oxime-single photon emission computed tomography (HMPAO-SPECT) showed markedly high blood perfusion in the right parieto-temporo-occipital areas. Considering the distribution of EEG epileptiform activities and HMPAO-SPECT hyperperfusion, it is most likely that the ictal paresis of our patient was associated with epileptic activities at the sensorimotor area which caused either direct or indirect activation of an inhibitory system. Careful clinical consideration of the possibility of ictal paresis is needed in elderly patients, especially in those with preexisting dementia, because paresis can be as severe as complete flaccid hemiplegia and can last as long as for a week.