[Aortic Arch:Embryology and Remodeling].

A right aortic arch and aberrant subclavian artery result from an interruption in the remodeling of the pharyngeal arch arteries. We occasionally encounter this anatomical variation during angiography. Patients with disorders such as Down syndrome and congenital heart disease show a high incidence of an aberrant right subclavian artery, and this anomaly can cause symptomatic esophageal or tracheal compression. The root of the aberrant artery may show dilatation(referred to as a Kommerell diverticulum), dissection, intramural hematoma, or rupture necessitating cardiac intervention using a surgical or endovascular approach. Neurointerventionalists should have working knowledge of the anatomy to rapidly understand the anatomy and ensure a safe procedure. A left transradial approach should be considered if prior knowledge of the aberrant subclavian anatomy is available.

Functional characterization of variants found in Japanese patients with hereditary hemorrhagic telangiectasia.

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant form of vascular dysplasia. Genetic diagnosis is made by identifying loss-of-function variants in genes, such as ENG and ACVRL1. However, the causal mechanisms of various variants of unknown significance remains unclear. In this study, we analyzed 12 Japanese patients from 11 families who were clinically diagnosed with HHT. Sequencing analysis identified 11 distinct variants in ACVRL1 and ENG. Three of the 11 were truncating variants, leading to a definitive diagnosis, whereas the remaining eight were splice-site and missense variants that required functional analyses. In silico splicing analyses demonstrated that three variants, c.526-3C > G and c.598C > G in ACVRL1, and c.690-1G > A in ENG, caused aberrant splicing, as confirmed by a minigene assay. The five remaining missense variants were p.Arg67Gln, p.Ile256Asn, p.Leu285Pro, and p.Pro424Leu in ACVRL and p.Pro165His in ENG. Nanoluciferase-based bioluminescence analyses demonstrated that these ACVRL1 variants impaired cell membrane trafficking, resulting in the loss of bone morphogenetic protein 9 (BMP9) signal transduction. In contrast, the ENG mutation impaired BMP9 signaling despite normal cell membrane expression. The updated functional analysis methods performed in this study will facilitate effective genetic testing and appropriate medical care for patients with HHT.

Sinus reconstruction therapy for superior sagittal sinus dural arteriovenous fistula caused by parasagittal meningioma invasion: a case report.

A dural arteriovenous fistula (dAVF) involving the superior sagittal sinus (SSS) is relatively rare, and its clinical course is usually aggressive. Its concomitance with a tumor has rarely been reported. Here, we present a case of SSS dAVF due to meningioma invasion, which was treated with sinus reconstruction and endovascular embolization. A 75-year-old man who had undergone tumor resection for parasagittal meningioma 4 years prior presented with intra-ventricular hemorrhage. Computed tomography angiography and magnetic resonance imaging revealed recurrent tumor invasion into the SSS causing occlusion. Cerebral angiography revealed multiple shunts along the occluded segment of the SSS, diffuse deep venous congestion, and cortical reflux. Borden type 3 SSS dAVF was diagnosed. We first performed direct tumor resection, followed by stenting for the occluded SSS and partial embolization of the shunts. After a 6-month interval, transvenous occlusion of the SSS was performed along the stent, resulting in complete obliteration of the dAVF. Sinus reconstruction therapy was effective in the immediate improvement of venous hypertension, obtaining the access route to the fistulas, and eradicating the shunts.

Successful embolization of ventricular arteriovenous malformation supplied by the choroidal artery: A case report and literature review.

Background: Ventricular arteriovenous malformations (AVMs) are localized in the ventricles and are mainly fed by the anterior choroidal artery (AChoA) and posterior choroidal artery (PChoA). Surgical resection of ventricular AVMs is difficult as the lesions are localized deep in the brain. Therefore, endovascular treatment is expected to treat ventricular AVMs. However, embolization from the AChoA and PChoA carries the risk of ischemic complications. Even though there are some major reports on embolization strategies from the choroidal arteries, embolization of these arteries remains technically challenging. In this article, we report two successful cases of ventricular AVM embolization using AChoA and PChoA. Case Description: Case 1: A 34-year-old male presented with intraventricular hemorrhage (IVH). Subsequently, ventricular AVM embolization in the anterior horn was performed using n-butyl-2-cyanoacrylate (NBCA) through the AChoA and medial PChoA, and complete obliteration was observed without neurological deterioration. Case 2: A 71-year-old female presented with IVH. Subsequently, ventricular AVM embolization in the lateral ventricle was performed through the AChoA and lateral PChoA with Onyx and NBCA, and partial obliteration was observed without complications. Furthermore, Gamma Knife surgery for residual lesions resulted in complete obliteration. Conclusion: Embolization through the choroidal arteries for ventricular AVMs is an effective curative or adjunctive treatment.

Postsurgical dural supply to the spinal cord arteriovenous malformation in spinal arteriovenous metameric syndrome.

Dural supply from the external carotid system in cerebral arteriovenous malformations (AVMs) is well known, but actual angiographic evidence of dural supply to spinal cord AVMs (SCAVMs) has not been reported. Here, we report a case of dural supply to the conus SCAVM in the spinal arteriovenous metameric syndrome segment 25-30. Thirteen years after spinal surgery (T12-L2 laminoplasty), spinal angiography showed multiple dural supplies from the dorsal somatic branches, prelaminar arteries, and radiculomeningeal arteries to the SCAVM at the level of the previous spinal surgery. To the best of our knowledge, this is the first reported case with dural supply to the spinal cord. This case demonstrates that the extradural and extraspinal branches can supply the spinal cord in rare instances of spinal dural adhesions following repeated hemorrhages and surgical intervention under a metameric link background.

Cerebral venous thrombosis associated with hyperhomocysteinemia and iron-deficiency anemia induced by autoimmune gastritis: A case report and literature review.

Cerebral venous thrombosis (CVT) is a rare disease, occurring in 0.5%-1% of all patients with strokes. Systemic and hereditary diseases and traumas are potential causes of CVT. We report a case of CVT and systemic thromboembolism complicated with hyperhomocysteinemia and iron-deficiency anemia caused by autoimmune gastritis. A 47-year-old female patient was admitted to the emergency department due to difficulty in movement, impaired consciousness, and urinary incontinence. Brain computed tomography (CT) and magnetic resonance imaging (MRI) showed bilateral thalamic edema associated with venous sinus thrombosis and embolic cerebral infarction in the deep white matter of the bilateral cerebral hemispheres. In addition, contrast enhanced whole-trunk CT scan showed deep femoral thrombosis and pulmonary artery embolism. She had no medical history of diseases or drug use that may cause thrombosis. Blood test results revealed iron-deficiency anemia and hyperhomocysteinemia, which were determined to be the cause of systemic thromboembolism. The patient tested positive for intrinsic factor antibodies. Moreover, the patient was diagnosed with autoimmune gastritis by gastrointestinal endoscopy. Therapies including anticoagulant and replacement with iron and vitamin B12 were administered. The patient was discharged from the hospital without neurological deficits. A favorable clinical course was achieved with anticoagulant administration and replacement therapy with iron and vitamin B12 for cerebral arteriovenous embolism that developed due to autoimmune gastritis.

Syndromic vascular malformations related to the PIK3CA and RAS pathways: A clinical and imaging review.

Vascular malformations are a complex and diverse group of disorders. They may enlarge with time, impair quality of life, and even be fatal. While many are sporadic, others are part of inherited syndromes; several gene mutations responsible for vascular anomalies have been identified. The PI3K/AKT/mTOR and RAS/MEK/ERK cascades have been extensively studied, and new molecular agents targeting these cascades are being developed. Diagnostic imaging findings are increasingly used to guide genetic testing, and in some cases, pathognomonic imaging characteristics can lead to a specific diagnosis. We review each of the representative syndromes associated with PIK3CA and RAS cascades, with updates of the latest in clinical and imaging information.

Diagnostic accuracy of three-dimensional-rotational angiography and heavily T2-weighted volumetric magnetic resonance fusion imaging for the diagnosis of spinal arteriovenous shunts.

BACKGROUND: Spinal arteriovenous shunts (SAVSs) are rare entities occurring in various areas, from the craniocervical junction to the sacral level. Recently, better understanding of SAVS angioarchitecture and elucidation of its pathogenesis have become possible with the advancement of imaging techniques. However, the utility of fusing different image modalities for SAVS diagnostics has not been determined. This study aimed to investigate whether three-dimensional-rotational angiography (3D-RA) and 3D-heavily T2-weighted volumetric MR (3D-MR) fusion imaging would improve the diagnostic accuracy for SAVSs. METHODS: We retrospectively reviewed 12 SAVSs in 12 patients. Assessment of 3D-RA and 3D-RA/3D-MR fusion images for SAVS was performed by seven blinded reviewers. The final diagnosis was performed by two interventional neuroradiologists with extensive experience, and the interobserver agreement between the reviewers and the final diagnosis was calculated using κ statistics. The comparison of the interobserver agreement between 3D-RA and 3D-RA/3D-MR fusion images was performed for the diagnosis of SAVS subtypes. We also statistically compared the image-quality gradings (on a 4-grade scale) to delineate the 3D relationship between vascular malformations and the surrounding anatomical landmarks. RESULTS: The interobserver agreement for the 3D-RA/3D-MR fusion images was substantial (κ=0.7071) and higher than that for the 3D-RA images (κ=0.3534). Significantly better image quality grades were assigned to 3D-RA/3D-MR fusion images than to 3D-RA images (p<0.0001) for the evaluation of the examined 3D relationships. CONCLUSION: The 3D-RA/3D-MR fusion images provided better interobserver agreement of SAVS subtype diagnosis, allowing for detailed evaluation of the SAVS anatomical structures surrounding the shunt.

Endovascular treatment for ruptured cervical anterior spinal artery aneurysm caused by occlusive disease of bilateral vertebral arteries: A case report and literature review.

A cervical anterior spinal artery (ASA) aneurysm not concomitant with vascular malformations is extremely rare, and is treated by conservative management or direct surgery in most cases. The endovascular treatment approach for these lesions is not well-documented. We present a case of a ruptured flow-related cervical ASA aneurysm due to the occlusive disease of the bilateral vertebral arteries (VA) treated by endovascular therapy. A 77-year-old woman with acute onset of headache and right hemiparesis was transferred to our hospital. Computed tomography revealed subarachnoid hemorrhage thick in the posterior fossa. A cerebral angiogram showed tandem stenosis of the left VA and the occlusion of the right VA at the V4 segment, with an enlarged C4 radiculomedullary artery and a subsequent aneurysm on the ASA. VA angiography revealed retrograde flow through the lesion and ASA axis to posterior circulation, suggesting a flow-related etiology of the aneurysm. We embolized the aneurysm using a flow-directed microcatheter and coils, preserving the ASA axis. Then, we dilated the VA stenosis using stents to prevent aneurysm recurrence by reducing hemodynamic stress on the ASA.

[A Case of Bilateral Carotid Injury Caused by Vinyl Umbrella Penetration Successfully Treated with Endovascular Therapy].

Here, we have reported a case pertaining to a 59-year-old man with bilateral traumatic carotid artery injury caused by vinyl umbrella penetration who was successfully treated. The patient fell from the stairs while holding an umbrella, which penetrated his neck. On admission, the patient was in a comatose state and the umbrella had been removed. Active bleeding was observed on the left side of the neck. Hence, tracheal intubation was performed to support respiration. Neck and head contrast-enhanced CT revealed bilateral extravasations from the carotid arteries and right middle cerebral artery(MCA)occlusion. Left carotid angiography showed extravasation from the external carotid artery(ECA), which was treated with coil embolization. Right carotid angiography revealed bleeding from the ECA and internal carotid artery(ICA)and occlusion of the MCA. The ECA and ICA were occluded by coil and n-butyl-2-cyanoacrylate embolization. After the procedures, the patient developed a large right cerebral infarction with massive brain swelling; therefore, external decompression was performed. Subsequently, the patient became alert and was able to walk with support within a month. Bilateral carotid injury is severe and difficult to treat. Endovascular therapy may be effective for the management of bilateral carotid injuries.

De novo intracranial arteriovenous malformation development after endovascular treatment for a pial arteriovenous fistula in capillary malformation-arteriovenous malformation syndrome.

Capillary malformation-arteriovenous malformation (CM-AVM) syndrome is a newly described entity characterized by autosomal dominantly inherited multifocal capillary malformations caused by RASA1 mutations (CM-AVM1) or EPHB4 mutations (CM-AVM2). Concurrent high-flow vascular anomalies in the brain are often present in the form of intracranial AVM or arteriovenous fistula (AVF). These high-flow lesions are often identified at or soon after birth because of the characteristic unique capillary malformations or a systemic disorder due to a high-flow shunt, such as respiratory distress or heart failure. However, de novo intracranial AVMs have not been reported in patients with CM-AVM syndrome. Herein, we report the case of a six-year-old boy with CM-AVM1 who had been treated for an intracranial pial arteriovenous fistula approximately five years previously, in whom a de novo intracranial AVM was identified on a follow-up angiographic study. To the best of our knowledge, this report is the first to document a de novo intracranial AVM in a patient with CM-AVM. We recommend careful neuroimaging follow-up even if initial neuroimaging screening is negative because of the risk of de novo AVM development.

Japanese clinical practice guidelines for vascular anomalies 2017.

The objective was to prepare guidelines to perform the current optimum treatment by organizing effective and efficient treatments of hemangiomas and vascular malformations, confirming the safety, and systematizing treatment, employing evidence-based medicine (EBM) techniques and aimed at improvement of the outcomes. Clinical questions (CQs) were decided based on the important clinical issues. For document retrieval, key words for literature searches were set for each CQ and literature published from 1980 to the end of September 2014 was searched in Pubmed, Cochrane Library, and Japana Centra Revuo Medicina (JCRM). The strengths of evidence and recommendations acquired by systematic reviews were determined following the Medical Information Network Distribution System (MINDS) technique. A total of 33 CQs were used to compile recommendations and the subjects included efficacy of resection, sclerotherapy/embolization, drug therapy, laser therapy, radiotherapy, and other conservative treatment, differences in appropriate treatment due to the location of lesions and among symptoms, appropriate timing of treatment and tests, and pathological diagnosis deciding the diagnosis. Thus, the Japanese Clinical Practice Guidelines for Vascular Anomalies 2017 have been prepared as the evidence-based guidelines for the management of vascular anomalies.

Japanese Clinical Practice Guidelines for Vascular Anomalies 2017.

The objective was to prepare guidelines to perform the current optimum treatment by organizing effective and efficient treatments of hemangiomas and vascular malformations, confirming the safety and systematizing treatment, employing evidence-based medicine techniques and aimed at improvement of the outcomes. Clinical questions (CQ) were decided based on the important clinical issues. For document retrieval, key words for published work searches were set for each CQ, and work published from 1980 to the end of September 2014 was searched in PubMed, Cochrane Library and Japana Centra Revuo Medicina databases. The strengths of evidence and recommendations acquired by systematic reviews were determined following the Medical Information Network Distribution System technique. A total of 33 CQ were used to compile recommendations and the subjects included efficacy of resection, sclerotherapy/embolization, drug therapy, laser therapy, radiotherapy and other conservative treatment, differences in appropriate treatment due to the location of lesions and among symptoms, appropriate timing of treatment and tests, and pathological diagnosis deciding the diagnosis. Thus, the Japanese Clinical Practice Guidelines for Vascular Anomalies 2017 have been prepared as the evidence-based guidelines for the management of vascular anomalies.

Japanese clinical practice guidelines for vascular anomalies 2017.

The objective was to prepare guidelines to perform the current optimum treatment by organizing effective and efficient treatments of hemangiomas and vascular malformations, confirming the safety, and systematizing treatment, employing evidence-based medicine (EBM) techniques and aimed at improvement of the outcomes. Clinical questions (CQs) were decided based on the important clinical issues. For document retrieval, key words for literature searches were set for each CQ and literature published from 1980 to the end of September 2014 was searched in Pubmed, Cochrane Library, and Japana Centra Revuo Medicina (JCRM). The strengths of evidence and recommendations acquired by systematic reviews were determined following the Medical Information Network Distribution System (MINDS) technique. A total of 33 CQs were used to compile recommendations and the subjects included efficacy of resection, sclerotherapy/embolization, drug therapy, laser therapy, radiotherapy, and other conservative treatment, differences in appropriate treatment due to the location of lesions and among symptoms, appropriate timing of treatment and tests, and pathological diagnosis deciding the diagnosis. Thus, the Japanese Clinical Practice Guidelines for Vascular Anomalies 2017 have been prepared as the evidence-based guidelines for the management of vascular anomalies.

Novel RASA1 mutations in Japanese pedigrees with capillary malformation-arteriovenous malformation.

Capillary malformation-arteriovenous malformation (CM-AVM, MIM#608354) is a rare autosomal dominant disorder characterized by multiple cutaneous capillary malformations co-occurring with fast-flow vascular anomalies, such as arteriovenous malformation or fistula. Despite the identification of RASA1 as the first causative gene in Western patients with CM-AVM, there have been no literature reports of Japanese patients with this gene mutation. We herein report two Japanese pedigrees harboring multiple affected members with CM-AVM. Whole-exome sequencing in the two probands identified novel heterozygous mutations in RASA1, which were co-segregated with the disease in each family and were not reported in large-scale sequencing databases. One was a frameshift mutation and the other a splice-site mutation causing aberrant splicing, confirmed by a minigene assay. There were no other genes commonly disrupted among these probands. RASA1 was a major causative gene even in Japanese patients with CM-AVM, although obvious locus heterogeneity was known for this disease.

[Supratentorial Meningeal Melanoma with Nevus of Ota:A Case Report].

We present a rare case of supratentorial meningeal melanoma associated with ipsilateral nevus of Ota, and a review of the literature. The patient was a 32-year-old man with a right-sided nevus of Ota, presenting with unconsciousness. His CT and MRI scans revealed an extra axial tumor with dural tail signs; no lesion was detected on systemic examination. Intraoperatively, the tumor demonstrated black hyperpigmentation and was histologically diagnosed as malignant melanoma. Following surgery, he received radiotherapy and chemotherapy. For over a year and a half, the patient has shown no recurrence of the lesion.

Angiographic and Clinical Characteristics of Thoracolumbar Spinal Epidural and Dural Arteriovenous Fistulas.

BACKGROUND AND PURPOSE: The purpose of this study is to compare the angiographic and clinical characteristics of spinal epidural arteriovenous fistulas (SEAVFs) and spinal dural arteriovenous fistulas (SDAVFs) of the thoracolumbar spine. METHODS: A total of 168 cases diagnosed as spinal dural or extradural arteriovenous fistulas of the thoracolumbar spine were collected from 31 centers. Angiography and clinical findings, including symptoms, sex, and history of spinal surgery/trauma, were retrospectively reviewed. Angiographic images were evaluated, with a special interest in spinal levels, feeders, shunt points, a shunted epidural pouch and its location, and drainage pattern, by 6 readers to reach a consensus. RESULTS: The consensus diagnoses by the 6 readers were SDAVFs in 108 cases, SEAVFs in 59 cases, and paravertebral arteriovenous fistulas in 1 case. Twenty-nine of 59 cases (49%) of SEAVFs were incorrectly diagnosed as SDAVFs at the individual centers. The thoracic spine was involved in SDAVFs (87%) more often than SEAVFs (17%). Both types of arteriovenous fistulas were predominant in men (82% and 73%) and frequently showed progressive myelopathy (97% and 92%). A history of spinal injury/surgery was more frequently found in SEAVFs (36%) than in SDAVFs (12%; P=0.001). The shunt points of SDAVFs were medial to the medial interpedicle line in 77%, suggesting that SDAVFs commonly shunt to the bridging vein. All SEAVFs formed an epidural shunted pouch, which was frequently located in the ventral epidural space (88%) and drained into the perimedullary vein (75%), the paravertebral veins (10%), or both (15%). CONCLUSIONS: SDAVFs and SEAVFs showed similar symptoms and male predominance. SDAVFs frequently involve the thoracic spine and shunt into the bridging vein. SEAVFs frequently involve the lumbar spine and form a shunted pouch in the ventral epidural space draining into the perimedullary vein.

Endoscopic transmucosal direct puncture sclerotherapy for management of airway vascular malformations.

OBJECTIVES/HYPOTHESIS: To describe a multidisciplinary approach to the treatment of airway vascular malformations (venous or lymphatic) with direct suspension rigid laryngoscopy and direct puncture transmucosal bleomycin sclerotherapy injected under road-mapping fluoroscopic monitoring, supplemented by Dyna-computed tomography utilization. STUDY DESIGN: Case series. METHODS: We performed a retrospective medical record and imaging review of four patients with venous malformations or lymphatic malformations located in the airway. Patients were treated with a combination of direct suspension laryngoscopy or rigid nasopharyngoscopy and image-guided direct puncture bleomycin sclerotherapy. RESULTS: Two patients presented to our institution with extensive lymphatic malformation of the neck, parapharyngeal, and retropharyngeal spaces, and two presented with venous malformation of the nasopharynx and oropharynx. All patients were treated with multiple sclerotherapy and debulking procedures before undergoing combined direct transmucosal puncture bleomycin sclerotherapy guided by direct laryngoscopy or nasopharyngoscopy. All patients had complete resolution of disease while maintaining a safe airway. CONCLUSIONS: A multidisciplinary approach to airway vascular malformations with a combination of endoscopy and direct puncture bleomycin sclerotherapy was demonstrated to be a safe and effective treatment in our patient cohort. Direct laryngoscopy and nasopharyngoscopy provide easy access to the nasopharynx, oropharynx, retro- and/or parapharyngeal spaces and larynx. Unlike traditional agents, bleomycin induces minimal edema and therefore is an ideal substance to treat airway lesions.