Dysbiosis of Gut Microbiome Is Associated With Rupture of Cerebral Aneurysms.

BACKGROUND AND PURPOSE: Environmental factors are important with respect to the rupture of cerebral aneurysms. However, the relationship between the gut microbiome, an environmental factor, and aneurysm rupture is unclear. Therefore, we compared the gut microbiome in patients with unruptured intracranial aneurysms (UIAs) and ruptured aneurysms (RAs) to identify the specific bacteria causing the rupture of cerebral aneurysms. METHODS: A multicenter, prospective case-control study was conducted over one year from 2019 to 2020. The fecal samples of patients with stable UIAs and RAs immediately after onset were collected. Their gut microbiomes were analyzed using 16S rRNA sequencing. Subsequently, a phylogenetic tree was constructed, and polymerase chain reaction was performed to identify the specific species. RESULTS: A total of 28 RAs and 33 UIAs were included in this study. There was no difference in patient characteristics between RAs and UIAs: age, sex, hypertension, dyslipidemia, diabetes status, body mass index, and smoking. No difference was observed in alpha diversity; however, beta diversity was significantly different in the unweighted UniFrac distances. At the phylum level, the relative abundance of Campylobacter in the RA group was larger than that in the UIA group. Furthermore, the gut microbiome in the RA and UIA groups exhibited significantly different taxonomies. However, Campylobacter was focused on because it is widely known as pathogenic among these bacteria. Then, a phylogenetic tree of operational taxonomic units related to Campylobacter was constructed and 4 species were identified. Polymerase chain reaction for these species identified that the abundance of the genus Campylobacter and Campylobacter ureolyticus was significantly higher in the RA group. CONCLUSIONS: The gut microbiome profile of patients with stable UIAs and RAs were significantly different. The genus Campylobacter and Campylobacter ureolyticus may be associated with the rupture of cerebral aneurysms.

A Case of an Intraosseous Arteriovenous Fistula at the Squamous Part of the Occipital Bone with Spontaneous Occlusion of Diploic Venous Drainage.

Objective: An intraosseous arteriovenous fistula (AVF) is a rare fistula with an intracranial shunted pouch. A case of an intraosseous AVF at the squamous part of the occipital bone with spontaneous occlusion of diploic venous drainage is described. Case Presentation: The patient, a Japanese woman in her 80s, presented with headaches at the back of the head and a history of multiple unruptured cerebral aneurysms but no recent head trauma. MRA showed abnormal signals in the occipital diploic region, and DSA showed an intraosseous AVF with a shunted pouch in the squamous part of the occipital bone near the inion. This was not seen on MRA 6 months earlier. One month later, follow-up examinations showed spontaneous occlusion of the diploic venous drainage, leading to a change in retrograde drainage into the superior sagittal sinus. Transvenous coil embolization was performed, and the shunted pouch was completely occluded. Postoperatively, the patient's symptoms resolved, and subsequent follow-ups showed no recurrence of the AVF. Conclusion: This case suggested that the vascular architecture of intraosseous AVFs might change over a short period. Transvenous embolization was effective in obliterating the intraosseous shunted pouch.

A Case of Multiple Intracranial Hemorrhages due to a Ruptured Neoplastic Cerebral Aneurysm Secondary to Metastasis of Poorly Differentiated Parotid Gland Carcinoma.

Neoplastic cerebral aneurysms (NCAs) are rare. This study reported a case of an NCA secondary to a poorly differentiated carcinoma of the parotid gland. An 84-year-old Japanese woman undergoing treatment for parotid gland cancer was admitted to our hospital with headache and progressive loss of consciousness. Based on computed tomography (CT) and CT angiography (CTA), a diagnosis of subarachnoid hemorrhage due to rupture of a left posterior inferior cerebellar artery aneurysm was made, and emergency aneurysmectomy was performed. Pathological examination of the resected aneurysm showed an NCA secondary to parotid carcinoma. After the aneurysmectomy, her condition stabilized; however, 33 days later, the patient developed an intracerebral hemorrhage, and a new aneurysm was confirmed in the right middle cerebral artery. To the best of our knowledge, there have been no previous reports on cases of NCAs secondary to parotid carcinoma. The pathology and clinical course strongly suggest that NCAs derived from malignant tumors may have an aggressive course.

The Usefulness of the 3.1-mm-diameter 4K Rigid Endoscope for Intracerebral Hematoma Evacuation.

The indication for surgical intervention in spontaneous intracerebral hemorrhage remains controversial. Although many clinical trials have failed to demonstrate its efficacy over medical treatment, less invasive endoscopic treatment is expected to demonstrate its superiority. A novel endoscopic system for hematoma removal consisting of a 3.1-mm-diameter 4K high-resolution rigid endoscope was used.The system was used in eight cases of spontaneous intracerebral hemorrhage. It provided improved maneuverability of the surgical instrument while maintaining satisfactory image quality. The surgical goal was achieved in all cases without any complications, including perioperative rebleeding.Endoscopic hematoma removal using the 3.1 mm high-resolution endoscope is an alternative minimally invasive approach to spontaneous intracerebral hemorrhage with improved reliability.

A novel predictor of ischemic complications in the treatment of ruptured middle cerebral artery aneurysms: Neck-branching angle.

Objective: The risk factors of procedural cerebral ischemia (CI) in ruptured middle cerebral artery (MCA) aneurysms are unclear. This study proposed the neck-branching angle (NBA), a simple quantitative indicator of the aneurysm neck and branch vessels, and analyzed its usefulness as a predictor of procedural CI in ruptured MCA aneurysms. Methods: We retrospectively analyzed 128 patients with ruptured saccular MCA aneurysms who underwent surgical or endovascular treatment between January 2014 and June 2021. We defined the NBA as the angle formed by the MCA aneurysm neck and M2 superior or inferior branch vessel line. The superior and inferior NBA were measured on admission via three-dimensional computed tomography angiography on admission. We divided the patients into clipping (106 patients) and coiling (22 patients) groups according to the treatment. Risk factors associated with procedural CI were analyzed in each group. Results: Both groups showed that an enlarged superior NBA was a significant risk factor for procedural CI (clipping, P < 0.0005; coiling group, P = 0.007). The receiver operating characteristic curve showed the closed thresholds of the superior NBA with procedural CI in both groups (clipping group, 128.5°, sensitivity and specificity of 0.667 and 0.848, respectively; coiling group, 130.9°, sensitivity and specificity of 1 and 0.889, respectively). Conclusion: The NBA can estimate the procedural risk of ruptured MCA aneurysms. In addition, an enlarged superior NBA is a risk factor for procedural CI in both clipping and coiling techniques.

Prevalence of cerebral aneurysm in patients with acromegaly.

The prevalence of cerebral aneurysm was retrospectively investigated in 208 patients with acromegaly relative to the rate of cerebral aneurysm in a group of control subjects. Neuroradiological examinations of the cerebral vascular system were conducted in 208 acromegaly patients (101 men; mean age, 48.8 years). The prevalence of cerebral aneurysm in the acromegaly patients was compared to that in a control group consisting of 7,390 subjects who underwent "brain checkup" between 2006 and 2008 (mean age, 51.6 years). In the acromegaly group, cerebral aneurysm was detected in 4.3 % of patients. By sex, the prevalence was 6.9 % in males, a significantly proportion than that in the control group with an odds ratio of 4.40. The prevalence in females did not differ between the two groups. In the acromegaly group, the rate of hypertension was significantly higher in the patients with aneurysm compared to those without aneurysm. Multiple logistic regression identified acromegaly as a significant factor related to the prevalence of cerebral aneurysm in all male subjects; other factors, such as age, hypertension and smoking, were not found to be significant. A significantly higher prevalence of cerebral aneurysm was detected in male patients with acromegaly. This finding indicates that excess growth hormone or insulin-like growth factor 1 affects the cerebral vascular wall, resulting in aneurysm formation. In addition to known systematic complications in the cardiovascular, respiratory, metabolic, and other systems, the risk of cerebral aneurysm should be considered in the management of acromegaly.

Safety and Efficacy of Prasugrel Administration in Emergent Endovascular Treatment for Intracranial Atherosclerotic Disease.

Objective: Intracranial atherosclerosis disease (ICAD) is one of the most common causes of acute ischemic stroke. In endovascular treatment (EVT) for acute large vessel occlusion stroke-related ICAD, reocclusion of the recanalized artery due to in situ thrombosis is problematic. In this study, the safety and efficacy of prasugrel administration to avoid reocclusion of emergent EVT for ICAD was investigated. Methods: All consecutive emergent EVTs for ICAD between September 2019 and December 2022 were included in this study. The procedures were divided into two groups as receiving periprocedural prasugrel (PSG group) or not (non-PSG group). Target vessel patency on follow-up, postprocedural intracranial hemorrhage (ICH), and clinical outcome were compared between PSG and non-PSG groups. Results: A total of 27 procedures were included in this analysis. Nineteen target vessels were patent on follow-up and eight were non-patent. Fifteen patients received prasugrel (18.75 mg: 11 cases, 11.25 mg: 4 cases), and twelve patients did not receive prasugrel. The target vessel patency rate was better in the PSG group vs. non-PSG group (100% vs. 33.3%, respectively; p = 0.0002). The postprocedural ICH rate was not different between the groups (PSG: 40.0% vs. non-PSG: 25.0%; p = 0.68), and all ICHs were asymptomatic. Good clinical outcome (modified Rankin Scale score of 0 to 3 at discharge) was more frequent in the PSG group than that in the non-PSG group (66.7% vs. 16.7%, respectively; p = 0.019). Conclusion: Prasugrel administration was significantly associated with target vessel patency and good clinical outcome after emergent EVT for ICAD without increasing the symptomatic ICH rate. Prasugrel administration might be safe and effective to avoid reocclusion during and after emergent EVT for ICAD.

Truncal dystonia with isolated middle cerebral artery ischemia: A case report of revascularization therapy for dystonia.

Background: Dystonia is a rare movement disorder with some cases being difficult to treat. Although dystonia can occur as a symptom of moyamoya disease, few studies have reported truncal dystonia occurring with middle cerebral artery (MCA) stenosis. Here, we report a case of truncal dystonia with MCA occlusion. Case Description: The patient was a 48-year-old female clerical worker who lived alone. An abnormal cervical posture initially appeared 7 years before (right flexion). Symptoms improved with medication and botulinum toxin injection. Five years before this report, her symptoms worsened, so the dose of oral medication was increased and botulinum treatment was performed, but the symptoms did not improve. The patient showed decreased cerebral blood flow (CBF) in the cortical areas but not in the basal ganglia. We performed superficial temporal artery-MCA bypass surgery because we believed that the dystonia was due to right MCA stenosis. The patient's symptoms improved immediately after surgery, except for her mild cervical backbend. Seven months after the surgery, the patient's involuntary movements showed further improvement, and symptoms have not worsened even after 2 years. Conclusion: Revascularization therapy improved CBF and truncal dystonia and could be a viable treatment option for dystonia with ischemia in the MCA region. Extensive cerebral ischemia can result in cortical inhibition loss or over-adapted cerebral plasticity and cause dystonia. Revascularization therapy may be useful for patients with dystonia and decreased CBF in the MCA region.

Primary extragonadal germinoma of the medulla oblongata.

Extragonadal germ cell tumors rarely arise from the brain stem. In this report, the authors present a rare case of germinoma developing in the medulla oblongata. A 31-year-old woman complained of intractable hiccups, hoarseness, and swallowing disturbance. Magnetic resonance imaging showed a tumor located on the dorsal part of the medulla oblongata without any abnormalities in the pineal body and suprasellar regions. Histological diagnosis of surgically resected tumor was germinoma. Tumor cells were positive for alkaline phosphatase, c-kit, octamer-binding transcription factor 3/4, cytokeratin, and epithelial membrane antigen in immunohistochemistry. The patient received adjuvant chemotherapy and irradiation to the residual tumor and cerebral ventricles. The patient is alive without recurrence 6 months after the surgery.