Background and Objectives: Non-cystic manifestation of autosomal dominant polycystic kidney disease (ADPKD) is an important risk factor for cerebral aneurysms. In this report, we describe a rare spontaneous internal carotid artery (ICA) dissection in a patient with ADPKD. Observations: A 38-year-old woman with a history of ADPKD and acute myocardial infarction due to coronary artery dissection experienced severe spontaneous pain on the left side of her neck. Magnetic resonance imaging (MRI) revealed a severe left ICA stenosis localized at its origin. Carotid plaque MRI showed that the stenotic lesion was due to a subacute intramural hematoma. Close follow-up by an imaging study was performed under the diagnosis of spontaneous extracranial ICA dissection, and spontaneous regression of the intramural hematoma was observed uneventfully. Conclusions: When patients with a history of ADPKD present with severe neck pain, it is crucial to consider the possibility of a spontaneous ICA dissection. A carotid plaque MRI is beneficial in the differential diagnosis. Conservative management may benefit patients without ischemic symptoms.

Background: Whether hematoma expansion after aneurysmal rupture is always a sign of rerupture remains unclear. Hence, the present study aimed to assess the incidence and risk factors of hematoma expansion unrelated to aneurysmal rerupture after endovascular embolization for ruptured cerebral aneurysms. Methods: We included patients who underwent endovascular embolization for ruptured cerebral aneurysms within 48 h after onset at our institution between January 2009 and February 2014. The medical records of 70 consecutive patients were reviewed and analyzed retrospectively. Results: Hematoma expansion unrelated to aneurysmal rerupture occurred in 7 (10%) of 70 patients. Interestingly, four of seven patients had distal anterior cerebral artery (ACA) aneurysms. The interval from onset to aneurysm coiling was shorter in patients with hematoma expansion than in those without (P = 0.040). Conclusion: Early embolization of ruptured ACA aneurysms might increase the risk of hematoma expansion unrelated to aneurysmal rerupture because the procedures were conducted under systemic anticoagulation. It would be better to refer the patient for direct clipping if the patient has a distal ACA aneurysm with parenchymal hematoma at interhemispheric fissure. Delayed coil embolization, which means around 12–18 h delayed, might be another option for ruptured distal ACA aneurysms to prevent hematoma expansion.

Arteriovenous fistula (AVF) occurring within the craniocervical junction (CCJ) is an uncommon vascular anomaly. A 56-year-old man presented with cervical pain and gait disturbances. Computed tomography revealed a hematoma in the epidural space at the cervical spinal level. Subsequent cerebral angiography revealed an epidural shunt at the CCJ, leading to a diagnosis of epidural AVF (EDAVF). Transvenous embolization, performed under general anesthesia, successfully resolved the shunt. Transarterial embolization of CCJ-EDAVFs carries a substantial risk of ischemic complications. Conversely, transvenous embolization poses a lower risk of ischemic complications and has potential as a beneficial treatment option for CCJ-EDAVFs. Herein, we present a unique case of CCJ-EDAVF that was successfully treated with transvenous embolization

Arterial spin labeling (ASL) has shown promise in diagnosing, classifying, and evaluating cortical venous reflux in dural arteriovenous fistulas (DAVFs). However, its utility in the postoperative assessment of DAVFs remains underexplored due to limited clinical data. This study aimed to evaluate the diagnostic performance of ASL in the postoperative setting. In this single-center retrospective study, 48 patients with DAVF who underwent perioperative digital subtraction angiography (DSA) and pseudocontinuous ASL between January 2012 and June 2018 were included. ASL images were assessed for abnormal signal in cerebral venous drainage (CVD) areas or the superior ophthalmic vein (SOV) by two independent neurointerventionalists blinded to the DSA findings. Diagnostic performance metrics for ASL were calculated, and interobserver agreement was evaluated using Cohen's kappa (κ). Postoperative ASL demonstrated a sensitivity of 87.5 % (95 % CI, 81.0 %-94.0 %), specificity of 100 % (95 % CI, 100 %), and overall diagnostic accuracy of 95.8 % (95 % CI, 90.2 %-101.5 %). The positive predictive value was 100 % and the negative predictive value was 94.1 % (95 % CI, 86.2 %-102.0 %). The positive likelihood ratio was infinite, while the negative likelihood ratio was 12.5 (95 % CI, 3.4-45.7). Interobserver reliability was substantial, with κ = 0.70. ASL is a reliable noninvasive tool for postoperative surveillance of DAVF. Given its excellent specificity and high overall accuracy, ASL can serve as a valuable adjunct to DSA in the perioperative management of DAVF patients, although caution is warranted due to occasional false negatives.

Background/Objectives: Brain pericytes are contractile mural cells of the neurovascular unit whose responses to endothelin-1 (ET-1) are mediated primarily by endothelin type A (ETA) receptors. ET-1/ETA signaling has been implicated in pathological pericyte contraction in neurovascular disorders such as Alzheimer’s disease and in cerebrovascular dysfunction after subarachnoid hemorrhage, motivating pharmacological evaluation of selective ETA receptor antagonists at the pericyte level. Clazosentan is a selective ETA receptor antagonist used clinically for cerebral vasospasm; however, its pharmacodynamic effects on brain pericytes remain insufficiently characterized. Methods: Pericyte impedance-based contractile and recovery responses to ET-1 were evaluated by xCELLigence real-time cell index analysis. Pericyte viability, morphology, and ETA protein abundance were examined using Cell Counting Kit-8 assay, immunocytochemistry, and Western blotting. As a secondary barrier-related assessment, transendothelial electrical resistance (TEER) was measured in primary rat brain endothelial cell-based in vitro blood–brain barrier models. Results: ET-1 induced impedance-based contractile responses with a concentration-related trend, followed by recovery responses, and increased ETA protein abundance in a time- and concentration-related manner; clazosentan significantly attenuated ET-1-induced ETA upregulation. Repeated ET-1 exposure was associated with an enhanced subsequent ET-1-induced impedance-based contractile response and a more sustained response, suggesting contractile sensitization; both effects were significantly attenuated by clazosentan. Clazosentan did not overtly disrupt TEER-assessed barrier properties. Conclusions: These findings suggest that ET-1/ETA signaling may shift brain pericytes toward a sensitized contractile response state and that selective ETA blockade by clazosentan attenuates this process without overtly disrupting TEER-assessed barrier properties under the present in vitro conditions. These observations support further pharmacological characterization of clazosentan as a modulator of pericyte ET-1 responses.