論文

2009年以降の硬膜動静脈瘻(dAVF)のうち外科的治療をメインとした20例20手技(男性17例、女性3例、平均年齢57.9歳)について検討した。検討内容は病変の特徴、部位、治療方法、全治療における外科治療の頻度、位置付け、合併症とした。また、直達術を行う際に注意が必要であった4例を呈示した。

蝶形骨小翼部に発生する硬膜動静脈瘻はまれである．今回，incidentalに発見された蝶形骨小翼部硬膜動静脈瘻に対し，NBCAを用いた経動脈的塞栓術にて根治を行った症例を経験したため報告する．79歳，男性．腹部大動脈瘤の術前精査の頭部MRIにて前頭蓋底部の硬膜動静脈瘻を指摘され，当科紹介となった．血管撮影を行ったところ，蝶形骨小翼部に硬膜動静脈瘻を認めた．左内頚動脈から反回髄膜動脈・inferolateral trunk，および左外頚動脈から正円孔動脈・副硬膜動脈・中硬膜動脈が流入動脈となっていた．浅中大脳静脈を経由して前頭葉表面の静脈へ，また鉤静脈を経由して深中大脳静脈へ逆流し，静脈瘤を形成していた．出血予防のため経動脈的塞栓術を行った．反回髄膜動脈・inferolateral trunk・正円孔動脈をコイル塞栓し，副硬膜動脈をNBCAにて塞栓，中硬膜動脈よりシャント部までNBCAを流入させ，塞栓を終了した．術後眼症状や他の合併症なく経過し，再発を認めていない．蝶形骨小翼部の硬膜動静脈瘻を経験した．NBCAを用いた経動脈的塞栓術は同部位の治療として有効であった．

脊髄動静脈シャント(SAVS)にはいくつかのサブタイプがあり,病態の正確な理解と的確な診断が求められる.適切な治療のために血管内治療医と直達術者との連携が不可欠である.本報告では,当施設で診療を行ったSAVS49例51病変の各シャントタイプの治療選択と結果について検討した.シャントの部位はdural 19病変,epidural 12病変,perimedullary 10病変,radicular 7病変,ほか3病変であった.治療は直達術29回(65.9%),血管内治療15回(34.1%).直達術の全例で血管内治療医が治療戦略を直達術者と共有,手術では術中シャント同定の支援を行った.直達術で26病変が治癒(89.7%),血管内治療で治癒および有効塞栓が13病変(86.7%)であり,周術期合併症は4.5%,永続する症状は認めなかった.SAVS全体に対し血管内治療医は血管内治療を行うだけでなく,正確な診断の提供,直達術を含めた適切な方針の提案,術中にも支援を行うことで効果的な治療を遂行できる.(著者抄録)

【目的】我々は,文献上報告のない上眼窩裂周囲に多房性の静脈腔を伴う動静脈シャントを経験したため報告する.【症例】51歳女性で,幼少期に右眼窩内の血管奇形で右前頭側頭開頭による手術歴があった.右眼痛,右眼球突出,右眼球結膜充血を認めた.血管造影検査にて蝶形骨縁から中頭蓋底にかけての上眼窩裂付近に特異的な多房性の静脈腔を認め,その静脈壁に比較的限局した動静脈シャントを認めた.外頸動脈の末梢の分枝から栄養され,上眼静脈へシャント血流は流出していた.動静脈シャントが形成された静脈腔は,上眼静脈や海綿静脈洞に連続していたが,単一の静脈というよりは多房性の静脈構造であり,静脈奇形などに続発した動静脈シャントであると思われた.選択的経静脈的塞栓を行い,動静脈シャントは消失し,眼症状も消失した.【結論】眼窩血管奇形の術後に,動静脈シャントが残存した静脈壁に形成されることがある.経静脈的塞栓術が有効な治療となり得る.(著者抄録)

＜文献概要＞POINT ▼頭頸部癌の頸動脈浸潤例において,頸動脈合併切除を伴う拡大手術が予後に寄与するかどうかは明らかではないが,切除による長期生存例があることから,症例によって選択肢になりうる。▼頸動脈再建を行う場合には,術前に血管造影検査にて頸動脈遮断テストを行い,一時的な遮断に耐えることができるか評価する。また自家静脈グラフトによる血行再建を行う場合には,採取する血管について評価を行う。▼頸動脈再建手術では,周術期の出血リスクや脳血管障害の発生リスクがある。周術期管理には慎重を期す必要がある。

Objective: Hemangiopericytomas (HPCs) and solitary fibrous tumors (SFTs) have been categorized as the same disease entity, SFT/HPC, since 2016. SFT/HPC is one of the most highly vascularized brain tumors, distinct from meningioma. The angioarchitecture also differs between these tumors. Understanding these differences can help interventionalists perform presurgical embolization more safely and effectively.Methods: Vascular structures were analyzed in eight patients with central nervous system (CNS) SFT/HPCs, all of whom received presurgical embolization. The type of embolic materials used and the complication rates were compared between the CNS SFT/HPC cases and 39 meningioma cases treated within the same period. Characteristic angiographic features of SFT/HPC were identified, and we present their interpretation and utilization to inform embolization strategies.Results: Four angiographic features of SFT/HPCs were identified. 1) Persistence of tumor stain and 2) feeders from branches of the internal carotid artery or vertebral artery were observed in all cases, while 3) connecting feeders (highly dilated vessels that originate from branches of other feeder vessels and run along the surface of one tumor compartment to feed another compartment) were observed in five out of eight cases. 4) Finally, an intratumoral arteriovenous shunt was identified in one case. The frequency of liquid embolic material use was significantly higher in SFT/HPC cases than in meningioma cases. No complications were observed in SFT/HPC cases, and all tumors were effectively removed.Conclusion: The most appropriate presurgical embolization strategies differ between SFT/HPCs and meningiomas depending on the tumor angioarchitecture. A thorough understanding of the vascular anatomy is necessary for safe and effective embolization of SFT/HPCs.

Background: Some reports suggest the efficacy of mechanical thrombectomy (MT) for acute vertebrobasilar artery (VBA) occlusion. The major causes of VBA occlusion include cardioembolism (CE) and large-artery atherosclerosis (LAA). However, the clinical characteristics of each cause remain unclear, and they might be important for decision making related to the indications and strategy of MT. Objective: This study aimed to compare functional outcomes and factors affecting outcomes between patients with CE and LAA with acute VBA occlusion. Methods: This was a retrospective and prospective observational study using data from TREAT (Tokyo-Tama-Registry of Acute Endovascular Thrombectomy), a multicenter registry of MT for acute large-vessel occlusion in the Tokyo metropolitan area. Patients with VBA occlusion classified into CE and LAA groups were analyzed. The primary outcome was a modified Rankin Scale score of 0–2 at 90 days. Results: Seventy-nine patients (57 with CE and 22 with LAA) were eligible from January 2015 to March 2020. Despite significantly shorter puncture-to-recanalization and onset-or-last-well-known-to-recanalization times in the CE group, the primary outcome was not significantly different between the 2 groups (CE, 31.6% vs. LAA, 45.5%; P = 0.248). In the subgroup analysis, patients with CE had worse clinical outcomes in the onset-or-last-well-known-to-door time ≥180 minutes, onset-or-last-well-known-to-door time ≥300 minutes, and low posterior circulation Alberta Stroke Program Early CT Score (≤7) subgroups. Conclusions: Functional outcomes of VBA occlusion were not significantly different between CE and LAA. Based on the subgroup analysis, patients with CE might have poorer collateral status than do patients with LAA, and earlier recanalization might therefore be desired.

Objective: Cone-beam computed tomography (CBCT) images for skull base tumors provide detailed vascular information and localization in regard to surrounding bony structures. We report use of the CBCT fusion technique for skull base meningiomas. Methods: Six patients with petroclival or petrotentorial meningiomas supplied by multiple arterial systems were preoperatively evaluated using CBCT fusion imaging. Fusion images were reconstructed from three-dimensional rotational angiography with contrast agent injections from the internal carotid artery (ICA) and external carotid artery in 4 cases, vertebral artery and external carotid artery in 1 case, and ICA and vertebral artery in 1 case. Results: The feeding pedicles and tumor stains from 2 arterial systems were differentiated by separate colors. The courses and territories of the ICA dural feeders or ICA/vertebral artery pial feeders were easily distinguished from the external carotid artery dural feeders. Anastomoses between thin feeders from different arterial systems could be detected. Mixed stain (stain with both colors) was observed in some tumor compartments, suggesting dual supply from 2 arterial systems and the presence of peritumoral anastomoses. All patients underwent preoperative embolization without complications. Conclusions: CBCT fusion images clearly visualized the feeders from each arterial system, the vascular compartments within the tumor, and possible peritumoral anastomoses. This technique provides a substantial contribution to both preoperative embolization and surgical resection of skull base meningiomas.

Introduction: Although the ascending pharyngeal artery (APhA) is known as a main feeder of carotid body tumors (CBTs), its detailed architecture and embryological consideration have not been described. The objective of this study was to describe the architecture of a descending feeder of the APhA and to consider its origin embryologically through a review of our CBT embolizations. Methods: We retrospectively analyzed data from patients with CBTs who underwent transarterial embolization or angiographic examination–only between July 2010 and February 2017. The arterial supply of the tumors, the number of feeder pedicles, the mean tumor size, embolization materials, complication of embolization, and extent of tumor removal were assessed. The embryological origin of feeding artery was considered based on the literature. Results: Eighteen patients with 20 CBTs underwent preoperative embolization or angiographic examination. The number of feeder pedicles was significantly related to the size of the CBT (P = 0.0002). The main feeding artery was the descending branch of APhA, which was hypertrophied and tortuous (18/20, 90%). Embryologically, this artery originated from the musculospinal branch and is termed the “descending musculospinal branch”. Conclusion: The main feeder of the CBTs was the “descending musculospinal branch” of the APhA and needs special consideration such as dangerous anastomosis for embolization.

Objective: Brain tumors often become clinically evident during pregnancy; however, the mechanism has not been well elucidated. Purpose of this study is to investigate the influence of molecular genetic factors on the progression of brain tumors during pregnancy or the postpartum period. Methods: Twelve cases of brain tumors that presented during pregnancy or postpartum period were included: five gliomas, three meningiomas, two vestibular schwannomas, and two chordomas. Tumor samples were investigated by metaphase comparative genomic hybridization and immunohistochemistry, for chromosomal copy number aberration (CNA) and receptor expression of sex hormones and growth factors. Results: The results were correlated with the timing of tumor presentation in relation to the stage of pregnancy. EGFR, VEGFR-1/2, AR, and c-Myc were expressed in gliomas, PgR, ER, HER-2, VEGFR-1, EGF and VEGFR2 in meningiomas, VEGFR-1 in vestibular schwannomas, and EGFR, VEGFR-1/2, and c-Myc in chordomas. The CNAs of the tumors varied. Four of the five gliomas presented in the 2nd trimester, all three meningiomas in the 3rd trimester or postpartum period, and both of the two schwannomas in the late 2nd trimester. Expression of VEGFR-1/2 and EGFR was observed regardless of the timing of tumor presentation, whereas female hormone receptors and HER-2 were exclusively found in meningiomas. Interestingly, one anaplastic astrocytoma (IDH mut, non-codeleted) that progressed from precedent grade 2 tumor harbored amplification of the MYC locus. Conclusion: Progression of brain tumors during pregnancy is associated with various growth factors as well as sex hormones. The timing of presentation is likely dependent on molecular receptors specific to each tumor type.

Cerebral hyperperfusion syndrome is a rare but severe complication of carotid artery stenting or carotid endarterectomy. Staged angioplasty is reportedly an effective strategy to avoid cerebral hyperperfusion syndrome. We encountered a case of internal carotid artery stenosis with a rare clinical presentation of limb shaking that was successfully improved by staged angioplasty. To our knowledge, there are no reported cases of limb shaking treated with staged angioplasty. A 76-year-old woman presented with continuous chorea in her left lower limb and shoulder. Medical examination revealed a tiny cerebral infarction in the right corona radiata and severe right internal carotid artery stenosis. Angiography showed near occlusion of the right internal carotid artery. Staged angioplasty was performed to avoid the risk of cerebral hyperperfusion syndrome. The first angioplasty resulted in an expanded diameter of 2.5 mm and was followed by definitive carotid artery stenting using a closed-cell stent 3.5 weeks later. Limb shaking improved in a stepwise manner along with an improvement in internal carotid artery stenosis and distal flow state with no signs of cerebral hyperperfusion syndrome. Patients with internal carotid artery stenosis or occlusion presenting with limb shaking have been suggested to have impaired cerebrovascular reactivity, which is also thought to be a risk factor for cerebral hyperperfusion syndrome. The stepwise improvement in limb shaking observed in this case supports the idea that the pathophysiology of limb shaking is related to cerebral haemodynamic impairment. Measures to prevent cerebral hyperperfusion syndrome, including staged angioplasty, should be actively considered in patients with limb shaking because the symptoms themselves suggest severe hypoperfusion.

Introduction: Although spinal arteriovenous fistula (AVF) has been reported widely, AVF at the cauda equina is quite rare. We described a case of AVF at the cauda equina that was fed by the distal radicular artery (DRA). Case presentation: A 50-year-old woman presented with sudden weakness of the lower extremities. Magnetic resonance imaging (MRI) revealed a lesion with a highly intense signal at the conus medullaris, which was surrounded by several low-intensity signals (flow voids). Digital subtraction angiography revealed AVF at the cauda equina and that it was fed by the DRA, which was directly fed by the L3 segmental artery. We performed surgical resection of the AVF while monitoring motor-evoked potentials. The patient’s postoperative course was uneventful, and her neurological symptoms gradually resolved. MRI 2 years after surgery showed the disappearance of both intramedullary edema and the flow voids. Discussion: For the AVF, located at the cauda equina and fed by the DRA in this case, surgical resection or endovascular embolization could have been selected. We performed open surgery to achieve complete obliteration of the AVF, which led to postoperative functional recovery without any adverse events. However, only a limited number of AVFs at the level of the cauda equina have been reported, and treatment standards have not been established. Further studies of AVFs at the cauda equina are necessary to clarify the epidemiological characteristics and clinical outcomes with an appropriate sample size.

Background: The coexistence of vascular malformations in the conus medullaris and cauda equina has been rarely reported, and the complex angioarchitecture in multiple arteriovenous lesions remains poorly understood. Case description: A 17-year-old woman presented with a sudden-onset, stepwise worsening of weakness and pain in the bilateral legs. Angiography revealed conus medullaris arteriovenous malformation and cauda equina arteriovenous fistulas. One of the drainers was shared between the coexisting lesions and harboured a varix. Targeted embolisation of a fistulous point in the conus lesion was performed with precaution to prevent occluding the common drainage route, which led to symptom improvement with angiographical diminishment of the varix. Conclusions: Recognising that communications between drainers can be observed in multiple spinal arteriovenous lesions is important in facilitating a safe embolisation. Cautious assessment of angiogram with fusion images of cone-beam computed tomography and volumetric T2 magnetic resonance imaging can help in establishing the diagnosis and treatment strategy.

Objective: Pseudoaneurysms of the internal carotid artery (ICA) and sphenopalatine artery (SPA) are recognized as sources of arterial epistaxis following head and face trauma. However, epistaxis involving pseudoaneurysm of the anterior ethmoidal artery (AEA) is extremely rare.Case Presentation: A 25-year-old man experienced massive epistaxis due to a ruptured traumatic pseudoaneurysm of the AEA. The patient had suffered head and face trauma in a car accident. CT showed fractures of the frontal, ethmoidal, and maxillary bones, and he was managed conservatively. Nine days after the injury, he had sudden, massive epistaxis. Angiography showed a right AEA aneurysm, which was treated successfully with transarterial embolization using n-butyl-2-cyanoacrylate (NBCA).Conclusion: Although pseudoaneurysm of the AEA is a rare cause of epistaxis, it is important to consider this diagnosis, in addition to pseudoaneurysm of the SPA and ICA, when a patient has massive arterial epistaxis following a traumatic skull base fracture, especially if the fracture is adjacent to the ethmoid sinus. Transarterial embolization using glue is a feasible therapeutic option for this condition.

Background: Vasa vasorum (VVs) is a Latin word representing vessels of vessels. VVs are usually found on the adventitia of the parent vessel and infrequently reach the media and intima, depending on the size and type of the parent vessels and physiological and pathological conditions. The VVs include arteries, capillaries, veins, and lymphatic vessels, involving the oxygenation and nourishment of the vessel’s wall to sustain its healthy state. Accumulated studies have revealed that VVs are involved in various intracranial lesions, including atherosclerotic diseases, aneurysms, and shunt diseases. The current review aims to review and integrate past and recent findings and knowledge on VVs and to facilitate our understanding of VVs and intracranial pathology involving VVs. Methods: A literature review was carried out with a focus on the role of VVs by searching the Pubmed database. Results: We identified 71 articles that discuss the role of VVs. We discussed the anatomical structure, physiological significance, and pathological significance of the VV. Conclusion: VV is not only involved in the nutrition and metabolism of the vascular wall but is also deeply involved in the pathogenesis of inflammation, ischemia, and thrombosis of the vascular wall. In addition, in the central nervous system, intracranial vascular wall nutrient particularities and VVs are closely related to the pathogenesis of cerebral aneurysms, subarachnoid hemorrhage, arteriovenous shunt disease, atherosclerotic lesions, and other conditions.

Objectives: Spinal dural arteriovenous fistula (sDAVF) is a rare and often underdiagnosed spinal disease. Early diagnosis is required because the deficits are reversible and delays in treatment cause permanent morbidity. Although the abnormal vascular flow void is a critical radiographic feature of sDAVF, they are not always present. A characteristic enhancement pattern of sDAVF has been recently reported as the “missing-piece” sign which can lead to the early and correct diagnosis. Methods: We presented imaging findings, treatment decisions, and the outcome of a rare case of sDAVF, in which the “missing-piece” sign appeared atypical. Results: A 60-year-old woman developed numbness and weakness in her extremities. Spinal MRI revealed longitudinal hyperintensity in the T2-weighted image, extending from the thoracic level to medulla oblongata. At first, myelopathy with inflammation or tumor was suspected because of the lack of flow voids and vascular abnormalities in CT-angiography and MR-DSA. However, we administered intravenous methylprednisolone and her symptom got worse with the appearance of the “missing-piece” sign. Then, we successfully diagnosed sDAVF by angiography. The “missing-piece” sign was considered to derive from inconsistency of the intrinsic venous system of spinal cord, with the abrupt segments without enhancement. The same etiology was considered in our case. Conclusions: Detecting the “missing-piece” sign can lead to the correct diagnosis of sDAVF, even if the sign appeared atypical.

Patients with neurofibromatosis type 1 not only have characteristic skin findings but are also known to have vascular disorders due to vascular vulnerability. A 44-year-old man with previously undiagnosed neurofibromatosis type 1 was brought to the emergency room due to a sudden subcutaneous hematoma with no history of trauma. Angiography revealed extravasation from the parietal branch of the right superficial temporal artery, which was embolized with n-butyl-2-cyanoacrylate. However, the next day, the patient exhibited an increased subcutaneous hematoma, and new extravascular leakage was detected at the frontal branch of the superficial temporal artery, which was also embolized with n-butyl-2-cyanoacrylate. The patient had physical findings characteristic of neurofibromatosis type 1, such as café-au-lait spots, and was subsequently diagnosed with neurofibromatosis type 1. No obvious neurofibroma or any other subcutaneous lesion associated with neurofibromatosis type 1 was identified in the affected area. Massive idiopathic arterial bleeding in the scalp, although infrequent, can be fatal. Neurofibromatosis type 1 should be considered when a subcutaneous scalp hematoma is observed without a history of trauma, even if the facial skin structure appears normal. Neurofibromatosis type 1 is also known to have multiple sources of hemorrhage. Thus, it is important to repeatedly evaluate vascular structures via cerebral angiography, contrast-enhanced computed tomography, and magnetic resonance imaging, if necessary.