Case 1 presented congestive heart failure with atrial fibrillation. Echocardiography and cardiac catheterization demonstrated mitral regurgitation and communications between the right and left coronary arteries and pulmonary artery (PA). The fistula orifice was directly closed and mitral annuloplasty was done at the same time. Case 2 had a history of open mitral commissurotomy for mitral atenosis (MS), and was diagnosed as to be re-MS. Selective coronary angiography (CAG) newly documented an aberrant artery originating from the left coronary artery and draining into the distal right PA. At operation, the origin of the aberrant artery was successfully ligated, and mitral valve was replaced with a prosthetic one. This paper presented relatively rare types of coronary artery fistulae, focusing on the importance of routine CAG before open heart surgery and of consideration on the association of this anomaly in respect to perioperative myocardial protection.

A 53-year-old man underwent aortic and mitral valve replacement, but postoperative cardioangiograms unexpectedly demonstrated aneurysms that had developed right-anteriorly and exactly anteriorly to the ascending aorta. They were initially thought to be pseudoaneurysms formed at the sites of aortotomy for valve replacement and of the aortic hole made by the needle puncture for air-venting. Operative findings, however, strongly suggested that it was a DeBakey type II dissecting aneurysm with two entries at the same sites as described. It was found that almost all distal parts of the aneurysmal cavity, probably a pseudolumen, had been occluded with clots, leaving two round cavities at the entries, which were preoperatively observed as pseudoaneurysms. The entries were successfully closed with approximation of the aortic walls using cardiopulmonary bypass, and the patient survived the operation.

There are few reports describing stroke due to the acute occlusion of the vertebral artery (VA) origin successfully treated by endovascularily. The authors report a case of 78-year-old man suffering from stroke owing to acute VA origin occlusion associated with contralateral hypoplastic VA leading to basilar artery (BA) thrombosis. Cerebral angiography demonstrated that the right VA was occluded at its origin, the left VA was hypoplastic, and BA was filled with thrombus. The occlusion of VA origin was initially passed through with a microcatheter and microwire. Hereafter, angioplasty was performed followed by stenting with a coronary stent. The VA origin was successfully recanalized. Next, a microcatheter was navigated intracranially through the stent and fibrinolysis was performed for BA thrombus. The patient's symptoms gradually improved postoperatively. Stroke due to acute VA origin occlusion leading to BA thrombosis was successfully treated by angioplasty and stenting followed by intracranial fibrinolysis.
Angioplasty ; Basilar Artery ; Cerebral Angiography ; Fibrinolysis ; Stents ; Stress, Psychological ; Stroke ; Thrombosis ; Vertebral Artery

Purpose: We investigated the age distribution of cerebral saccular aneurysms in various locations to clarify the differences by location and discuss the mechanism of formation. Materials and Methods: We retrospectively assessed clinical material obtained from 1,252 unruptured aneurysms treated with endovascular embolization between 2004 and 2019. Age, sex, laterality, and size were investigated by the location of aneurysms, classified as cavernous internal carotid artery (ICA), paraclinoid ICA, supraclinoid ICA, anterior communicating artery, anterior cerebral artery, middle cerebral artery, basilar artery complex, and posterior inferior cerebellar artery. Paraclinoid aneurysms were subclassified into 3 patterns according to their projecting direction: S-type, with superior protrusion; M-type, with medial protrusion; and P-type, with posteroinferior protrusion. Results: There was no significant difference by location for sex, laterality, and size. The mean age of patients with paraclinoid aneurysms (56.5 years old) was significantly lower than that of other aneurysm patients (64.3 years old). Notably, 40% of the patients with M-type aneurysms were <50 years old. This percentage was significantly higher than that of aneurysms at other locations (P<0.05). Conclusion We found a young female predominance for patients with paraclinoid carotid aneurysms. This study may suggest that congenital factors contribute to paraclinoid aneurysm formation as well acquired factors, such as hemodynamic stress, atherosclerotic wall damage, and local inflammation.

Purpose: We investigated the age distribution of cerebral saccular aneurysms in various locations to clarify the differences by location and discuss the mechanism of formation. Materials and Methods: We retrospectively assessed clinical material obtained from 1,252 unruptured aneurysms treated with endovascular embolization between 2004 and 2019. Age, sex, laterality, and size were investigated by the location of aneurysms, classified as cavernous internal carotid artery (ICA), paraclinoid ICA, supraclinoid ICA, anterior communicating artery, anterior cerebral artery, middle cerebral artery, basilar artery complex, and posterior inferior cerebellar artery. Paraclinoid aneurysms were subclassified into 3 patterns according to their projecting direction: S-type, with superior protrusion; M-type, with medial protrusion; and P-type, with posteroinferior protrusion. Results: There was no significant difference by location for sex, laterality, and size. The mean age of patients with paraclinoid aneurysms (56.5 years old) was significantly lower than that of other aneurysm patients (64.3 years old). Notably, 40% of the patients with M-type aneurysms were <50 years old. This percentage was significantly higher than that of aneurysms at other locations (P<0.05). Conclusion We found a young female predominance for patients with paraclinoid carotid aneurysms. This study may suggest that congenital factors contribute to paraclinoid aneurysm formation as well acquired factors, such as hemodynamic stress, atherosclerotic wall damage, and local inflammation.

Transarterial embolization using Onyx is a well-established treatment for dural arteriovenous fistulas (DAVFs). However, complications can arise when Onyx migrates into the venous side, impairing the draining veins. We encountered a case where Onyx, injected through the arterial side, strayed into the jugular vein, forming a hairball-like structure. Our study aimed to investigate the underlying mechanism of this unusual phenomenon. We postulated that Onyx precipitates into thread-like shapes when passing through extremely narrow openings. To test this, we extruded Onyx from a syringe through a 27-gauge needle into a silicone tube with flowing water. By varying the flow speed, we observed the hardening behavior of Onyx. Under slow flow, the extruded Onyx quickly solidified at the needle tip, forming a round mass. Conversely, high-speed flow resulted in Onyx being dispersed as small pieces. We successfully replicated the formation of “Onyx threads” under continuous slow flow conditions, similar to our case. This phenomenon occurs when Onyx unexpectedly migrates to the draining vein through a tiny opening during transarterial embolization for arteriovenous shunt diseases. Early recognition and appropriate measures are necessary to prevent occlusive complications in the draining veins and the pulmonary system.

Hands-on training is a crucial part of education in neuroendovascular treatment to ensure safe and rapid acquisition of techniques. However, there is a significant gap between training and actual clinical practice. This study will introduce innovations for more practical thrombus retrieval training that was developed in this process. A Smart Vascular Model 3 in 1 was used. A pink pseudothrombus was inserted into the M1 (horizontal segment of the middle cerebral artery) section of the model. Then, a “red underlay” purchased at a stationery store was placed to cover the proximal part of M1 and beyond so that the pseudothrombus was not visible. The thrombus was retrieved during training by looking for the location of the thrombus based on the behavior and resistance of the tip of the guidewire and deployment of the stent retriever. The participants were required to have detailed observation skills and precise manipulation skills using a red film to prevent the direct visualization of the pseudothrombus. The implementation of this innovation to the previous hands-on training made the training more practical and effective. If the exact thrombus location can be determined by the behavior of the wire tip, the device’s capabilities can be maximized, and rapid retrieval can be expected. It could also reduce complications, as unnecessary peripheral guidance of the device could be avoided.

Dural arteriovenous fistula (DAVF) is classically defined as abnormal arteriovenous connections located within the dural leaflets. Though the exact etiology is still not clear, they are generally accepted as acquired lesions. However, some DAVFs formed as the congenital disorders are called dural arteriovenous malformations and these lesions with a marked cortical venous reflux are considered to be aggressive and warrant an early intervention. The authors describe a case of 35-year-old man presented with unique type of DAVF. The fistula was located adjacent to the confluence of venous sinuses with multiple feeders. The feeders drained into a large venous pouch just anterior to the confluence which had a bilateral venous drainage. This was associated with multiple cerebellar venous ectasia along the draining cortical vein. It was managed by staged endovascular procedures and complete cure could be achieved. The pathogenesis and technique of embolization of this complex fistula/malformation are also discussed.
Arteriovenous Malformations ; Central Nervous System Vascular Malformations ; Congenital, Hereditary, and Neonatal Diseases and Abnormalities ; Dilatation, Pathologic ; Drainage ; Early Intervention (Education) ; Endovascular Procedures ; Fistula ; Varicose Veins ; Veins

The interventional neuroradiology (INR, or neurointerventional surgery) became a rapidly emerging specialty since the first Working group in Interventional Neuroradiology (WIN) meeting was held in Santa Barbara in 1980 by 15 pioneers. Although the specialty has been led by neuroradiologists, other specialists of neurosurgery and neurology have become involved. Due to diverse background of the specialties with inadequate requirement of education and training, proper level of training standard and quality assurance may be achieved for outcomes of treated patients with neurovascular diseases. In East Asia, there are less inter-relationship of education and training among China, Japan and Korea when compared to the learning opportunities in western countries from the three nations. Therefore, we present the current status and difference of medical education system and compare INR training to improve understanding of INR development in the adjacent countries.
China ; Education, Medical ; Far East ; Humans ; International Normalized Ratio ; Japan ; Korea ; Learning ; Neurology ; Neurosurgery ; Specialization

For many years, the pathophysiology of idiopathic intracranial hypertension (IIH) was interpreted as “secondary intracranial hypertension,” and IIH was considered to be caused by brain edema due to obstructive sleep apnea. Another theory proposed cerebrospinal fluid (CSF) absorption impairment due to excessive medication with vitamin A derivatives. Other reports pointed out the importance of obesity, which may cause an impairment of intracranial venous drainage due to elevated right atrial pressure. Patients with medically refractory IIH have traditionally undergone a CSF diversion. Venous outlet impairment on IIH has recently been reported as a causative or contributory cause, and thus focused venoplasty of the stenotic sinus with a stent has emerged as a new treatment strategy. We report the cases of two patients who presented with headache and papilledema with IIH. They successfully underwent stent placement at the stenosis of the transverse sinus and experienced complete resolution of symptoms.
Absorption ; Atrial Pressure ; Brain Edema ; Cerebrospinal Fluid ; Constriction, Pathologic* ; Drainage ; Headache ; Humans ; Obesity ; Papilledema ; Pseudotumor Cerebri* ; Sleep Apnea, Obstructive ; Stents* ; Vitamin A