"The microcatheter contrast injection technique": A novel technique to detect the proximal end of a thrombus in mechanical thrombectomy.

Background: An aspiration catheter needs to attach to a thrombus in order to achieve first-pass recanalization by mechanical thrombectomy (MT) for acute ischemic stroke (AIS), particularly that using a direct aspiration first pass technique. The meniscus sign, which is defined as meniscoid contrast opacification indicating the proximal edge of a thrombus, has been suggested to contribute to successful recanalization. In some cases, the meniscus sign is not detected following an injection of contrast medium through a guiding catheter. To precisely identify the location of a thrombus, we use "the microcatheter contrast injection (MCI) technique," which accurately shows the proximal edge of a thrombus. We herein introduce this novel technique and discuss its efficacy in MT. Methods: In cases without the meniscus sign, a microcatheter was advanced to the distal end of contrast opacification, and contrast medium was injected through the microcatheter to detect the meniscus sign. An aspiration catheter was then advanced to the thrombus indicated by the meniscus sign and slowly withdrawn under aspiration. Results: 29 patients underwent MT for AIS using the MCI technique. Even in cases without the meniscus sign on initial angiography, the MCI technique accurately revealed the proximal edge of the thrombus. Moreover, middle cerebral artery occlusion due to atherosclerotic stenosis and displacement of the aspiration catheter and thrombus axis were detected using this technique. Conclusions: The MCI technique may effectively reveal the exact site of a thrombus and increase the success rate of first-pass recanalization.

Angioarchitecture of the hemorrhagic developmental venous anomaly with stenosis of the collecting vein and cavernous malformation: a case report.

We herein report a case of developmental venous anomaly (DVA) with venous congestion caused by stenosis of the collecting vein that presented with intracerebral hemorrhage (ICH). A 74-year-old woman was referred to our hospital a few days after the onset of motor aphasia. Computed tomography (CT) and magnetic resonance imaging (MRI) showed ICH in the left frontal lobe. Angiography revealed DVA in the left frontal lobe in the late venous phase. Stenosis of the collecting vein of DVA at the entrance to the superior sagittal sinus was detected and accompanied by cavernous malformation (CM) beside DVA. Cone-beam CT revealed the absence of the left septal vein and hypoplastic transverse caudate veins. The patient was treated by blood pressure management and no additional neurological symptoms were detected. DVA develops to compensate for the absence of pial or deep venous systems, and generally benign and clinically asymptomatic. However, the outflow restriction of DVA causes chronic venous hypertension and the formation of CM. These abnormalities are considered to occur during post-natal life and may result in ICH. The risk of hemorrhage needs to be considered in cases of DVA with restricted venous outflow or CM.

Cerebral Infarction Due to Occlusion of Main Trunk of Middle Cerebral Artery in Patient with Accessory Middle Cerebral Artery.

The existence of an accessory middle cerebral artery (AMCA) usually has no pathological significance. Three patients developed cerebral infarction due to thromboembolic occlusion of the main trunk of the middle cerebral artery (MCA). In these patients, AMCA originating from the anterior cerebral artery was intact, and ran to the lateral side along the main MCA. Emergency endovascular treatment to remove the thrombus in the main MCA was performed, and MCA was recanalized. In one patient, the main MCA re-occluded and cerebral infarction developed on the next day. The diameter of AMCA is commonly smaller than that of the main MCA. Therefore, volume of ischemic region depends on the collateral blood flow to the left MCA territory by AMCA. Once an anomalous MCA is detected in a patient with cerebral infarction involving the MCA territory, close examinations to assess the anatomy of both the main and anomalous MCA are mandatory.

Carotid artery stenting for spontaneous internal carotid artery dissection presenting with hypoglossal nerve palsy: A case report.

Background: Some studies reported cases of internal carotid artery (ICA) dissection (ICAD) that was treated by carotid artery stenting (CAS). Symptoms of ICAD resulting from the lower cranial nerve palsy are rare and the treatment strategy is not clearly defined. We report a patient with ICAD showing hypoglossal nerve palsy alone that was treated by CAS. Case Description: A 47-year-old man presented with headache, dysphagia, dysarthria, and tongue deviation to the left. He had no history of trauma nor any other significant medical history. Axial T2-CUBE MRI and MRA showed dissection of the left ICA accompanied with a false lumen. These findings indicated that direct compression by the false lumen was the cause of hypoglossal nerve palsy. Although medical treatment was continued, symptoms were not improved. Therefore, CAS was performed to thrombose the false lumen and decompress the hypoglossal nerve. His symptoms gradually improved after CAS and angiography performed at month 6 showed well-dilated ICA and disappearance of false lumen. Conclusion: CAS may be an effective treatment for the lower cranial nerve palsy caused by compression by a false lumen of ICAD.

Bow hunter's syndrome treated by anterior decompression with fusion: A case report.

Background: Bow hunter's syndrome (BHS) is a rare condition induced by occlusion or compression of the vertebral artery (VA) during head movement or rotation. Here, we report a patient with BHS effectively treated with an anterior cervical discectomy and fusion (ACDF). Case Description: A 75-year-old male experienced recurrent embolic strokes to the posterior circulation. This was attributed angiographically to transient stenosis of the right VA due to a right-sided C5-C6 osteophyte when the head was rotated to the right; the stenosis was improved when the patient rotated his head to the left. The patient successfully underwent a C5-C6 ACDF for removal of the right-sided lateral osteophyte which resulted in no further transient right-sided VA occlusion. Conclusion: Following a C5-C6 ACDF for removal of a right lateral osteophyte, a 75-year-old male's intermittent right-sided VA occlusion responsible for multiple posterior circulation emboli was relieved.

Characteristics and Management of Ruptured Aneurysms Originating from the Penetrating Artery of the Distal Middle Cerebral Artery.

We report a rare case of an aneurysm originating from the penetrating artery of the distal middle cerebral artery (MCA). A 76-year-old man without a notable past history presented with sudden-onset severe headache, left hemiparesis, and a decreased level of consciousness. Computed tomography (CT) revealed subarachnoid hemorrhage (SAH) with intracerebral hemorrhage (ICH) in the right temporal lobe extending into the ventricle. Contrast-enhanced CT (CE-CT) demonstrated a focus of contrast enhancement (CE) adjacent to the hematoma in the right frontal lobe. An aneurysm fed by a penetrating artery branching off from the right distal MCA was found on angiography. The patient underwent emergency resection of the aneurysm and hematoma evacuation. Histological analysis revealed that arterial dissection may be an associated factor in the pathogenesis of this peripheral aneurysm formation. A focus of CE within or adjacent to the hematoma may be useful for diagnosing this peripheral aneurysm. ICH can result in a life-threatening situation. Therefore, microsurgery may be the first treatment choice for aneurysms in this location.

Hemifacial spasm caused by vertebral artery aneurysm treated by endovascular coil embolization.

BACKGROUND: Hemifacial spasm (HFS) caused by vertebral artery (VA) aneurysms is rare. Several cases of HFS caused by VA aneurysms treated by endovascular parent artery occlusion (PAO) have been reported. Recently, we treated a rare case of HFS caused by a saccular VA aneurysm at the bifurcation of the posterior inferior cerebellar artery (PICA), which was successfully treated by endovascular coil embolization, preserving the parent artery, and PICA. We discuss endovascular treatment for HFS induced by VA aneurysms with a literature review. CASE DESCRIPTION: A 59-year-old man presented with the left HFS persisting for 2 months. Magnetic resonance imaging revealed a left saccular VA-PICA aneurysm and demonstrated that a left facial nerve was compressed by the aneurysm at the root exit zone. Angiography revealed that the PICA was branching from the aneurysm neck. Endovascular coil embolization was performed using the balloon remodeling technique to preserve the left VA and PICA. HFS disappeared after treatment. CONCLUSION: Although microvascular decompression was commonly accepted for the standard treatment of HFS, coil embolization of aneurysms without PAO may be an effective treatment for HFS caused by VA aneurysms.