Impact of Pre-operative Embolization With Onyx for Brain Arteriovenous Malformation Surgery.

Objective: To clarify the safety and efficacy of pre-operative embolization using Onyx liquid embolic agent (Onyx; ev3) compared with N-butyl cyanoacrylate (NBCA; Cordis Neurovascular, Inc.) or coils in cerebral arteriovenous malformation (AVM) surgery. Methods: This was a retrospective review of a prospectively collected clinical database of brain AVMs treated at our institute from January 2005 to March 2021. A total of 38 consecutive patients who underwent AVM resection after pre-operative embolization were included. Based on pre-operative embolization materials, the patients were divided into the pre-Onyx group (n = 16), in which NBCA or coils were used for embolization, and the Onyx group (n = 22). Patient characteristics and treatment results were compared between the two groups. Results: Patient characteristics were comparable between the two groups in terms of age, sex, and rupture status. While the Spetzler-Martin grade was also similar between the two groups, the location of the AVM nidus in the eloquent area was slightly higher in patients in the Onyx group (72.7%) than in patients in the pre-Onyx group (43.8%) (P = 0.09). The embolization rate was higher in the pre-Onyx group (mean: 63.0%; range: 12.7-100%) than in the Onyx group (mean: 50.0%; range: 15.8-100%), but the difference was not statistically significant (P = 0.06). The time needed for surgical removal was shorter in the Onyx group (mean: 354.8 min; range: 144-884 min) than in the pre-Onyx group (mean: 457.9 min; range: 240-1,294 min); however, this difference was not statistically significant (P = 0.13). The amount of intraoperative bleeding was significantly lower in the Onyx group (mean: 129.8 ml; range: 20-540 mL) than in the pre-Onyx group (mean: 448.8 mL; range: 120-1,550 ml) (P = 0.0008). The surgical complication rates were comparable between the two groups (pre-Onyx group, 18.8%; Onyx group, 4.5%; P = 0.29). Conclusions: Pre-operative embolization with Onyx can significantly reduce the amount of intraoperative bleeding in AVM resection and may contribute to safe AVM surgery.

A Spontaneous Extracranial Internal Carotid Artery Dissection with Autosomal Dominant Polycystic Kidney Disease: A Case Report and Literature Review.

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.

[A Case of Embolic Infarction Associated with Accessory Middle Cerebral Artery and Treated Using Mechanical Thrombectomy].

The accessory middle cerebral artery(AMCA)is an anatomical variant of the MCA. It originates from the anterior cerebral artery, reaches the sylvian fissure, and supplies the territory of the middle cerebral artery. We report a case of embolic infarction associated with the AMCA that was treated using mechanical thrombectomy. An 82-year-old man with chronic atrial fibrillation experienced a sudden onset of left hemiparesis and was brought to our hospital. Magnetic resonance imaging showed a right temporal lobe, parietal lobe, and basal ganglion infarction, and indicated right internal carotid artery(ICA)occlusion. Mechanical thrombectomy using a Penumbra system was performed with complete recanalization. Final angiography revealed the existence of the AMCA, and the thrombus was located at the right ICA C2 portion to the main MCA. There have been twelve reported cases of ischemic stroke associated with the AMCA, including the present case. We summarized the data from the reported cases of ischemic stroke with an AMCA and evaluated their clinical characteristics and the pitfalls of endovascular treatment. These cases suggest that the AMCA may play a role in collateral flow around the main MCA occlusion, but provides insufficient collateral blood supply. Owing to the anatomical characteristics of the AMCA, we should pay attention to possible complications of endovascular treatment.

Pulmonary pleomorphic carcinoma with few PD-1-positive immune cells and regulatory T cells that showed a complete response to nivolumab.

Pulmonary pleomorphic carcinoma has been shown to respond remarkably to PD-1 inhibitors; however, the biomarkers for this therapy have not been fully proven. We report a case of pulmonary pleomorphic carcinoma with overexpressed PD-L1, in which a complete response to nivolumab was sustained for >14 months. Immunohistochemical analysis revealed few PD-1+ immune cells and regulatory T cells in the tumor, in addition to predominant infiltration of CD8+ cells and macrophages. Our findings suggest that the presence of a small number of PD-1+ immune cells and regulatory T cells should be investigated as candidate therapeutic biomarkers.