総説・解説等

Background and purpose: Macro-arteriovenous fistulas (MAVFs) are arteriovenous shunts draining into a giant venous ectasia. They can be treated by surgery or embolisation. Angiographic controls are usually performed rapidly after treatment in order to prove the cure of the lesion but no long term angiographies are generally scheduled. We wanted to control the stabilities of such lesions at follow-up. Method: Clinical history and imaging of ninety-five patients with high flow shunts draining into venous ectasias (MAVFs, Vein of Galen malformations and dilatations) were reviewed. Results: De novo arteriovenous shunts related to angiogenesis involving vasa vasorum developed in three patients with MAVFs at various intervals. Genetic underlying conditions as HHT or RASA 1 mutations were suspected in each patient. Conclusions: Neo-angiogenesis can occur after cure of MAVFs. Long term imaging follow-ups should be considered as the natural history of such recurrent shunts is currently unknown.

Background and Purpose: There has been limited literature regarding the bridging veins (BVs) of the medulla oblongata around the foramen magnum (FM). The present study aims to analyze the normal angioarchitecture of the BVs around the FM using slab MIP images of three-dimensional (3D) angiography. Methods: We collected 3D angiography data of posterior fossa veins and analyzed the BVs around the FM using slab MIP images. We analyzed the course, outlet, and number of BVs around the FM. We also examined the detection rate and mean diameter of each BV. Results: Of 57 patients, 55 patients (96%) had any BV. The median number of BVs was two (range: 0–5). The BVs originate from the perimedullary veins and run anterolaterally to join the anterior condylar vein (ACV), inferior petrosal sinus, sigmoid sinus, or jugular bulb, inferolaterally to join the suboccipital cavernous sinus (SCS), laterally or posterolaterally to join the marginal sinus (MS), and posteriorly to join the MS or occipital sinus. We classified BVs into five subtypes according to the draining location: ACV, jugular foramen (JF), MS, SCS, and cerebellomedullary cistern (CMC). ACV, JF, MS, SCS, and CMC BVs were detected in 11 (19%), 18 (32%), 32 (56%), 20 (35%), and 16 (28%) patients, respectively. The mean diameter of the BVs other than CMC was 0.6 mm, and that of CMC BV was 0.8 mm. Conclusion: Using venous data from 3D angiography, we detected FM BVs in most cases, and the BVs were connected in various directions.

Enhancing subdural effusions (SDEs) after angiography may imitate acute subdural hematoma (ASDH), and differentiation between these two clinical entities is sometimes confusing. We present a case of enhancing SDE mimicking ASDH after an endovascular procedure for head trauma. Although dual-energy CT (DECT) might be an ideal tool for this situation, it is not available in every hospital. In addition, the standard protocol to distinguish these two clinical entities has not been well established. We demonstrate that the comparison of CT attenuation values of the dural sinus and subdural collection is key to differentiation, and comprehensive radiological and clinical evaluation based especially on the kinetics of contrast agents should be carefully considered.

OBJECTIVE Few classifications of intradural spinal arteriovenous shunts (ID-SAVSs) have considered their anatomical localization in relation to their phenotype and angioarchitectonics. The authors propose another vision of ID-SAVSs allowing a reappraised classification based on analysis of the anatomical disposition, angioarchitecture, and histogenetic location of these vascular malformations. METHODS The radiological and clinical records of 210 patients with ID-SAVSs were retrospectively reviewed, considering their localization, vascular architectonics, and correlation with the 5 histogenetic units of the spinal cord. Among these, 183 files with complete data allowed precise analysis of the ID-SAVSs. RESULTS Among these 183 files (162 and 21 cases with single and multiple lesions, respectively), different entities were identified: 13 pial macro arteriovenous fistulas (MAVFs), 92 pial micro arteriovenous fistulas (mAVFs), 33 superficial pial niduses, and 69 intramedullary niduses. Thirteen sulcal shunts (either fistulas or niduses) were considered subtypes of pial lesions. Among the 21 multiple cases, 11 were monomyelomeric while 10 were multimyelomeric. Pial lesions, either fistulas or niduses, were dominantly vascularized by pial arteries (anterior or posterior depending on the localization of the shunt) and occasionally (except for MAVFs) by transmedullary arteries. Pial niduses occasionally extended into the funiculus by recruiting intrinsic veins or by extension of the nidus itself inside the white matter. Intramedullary niduses were always vascularized by both centrifugal and centripetal feeders, respectively, from sulcal arteries (SAs) and pial arteries. Sulcal lesions are pial lesions located within the ventral median sulcus and vascularized by SAs and veins. Single or multiple ID-SAVSs can be part of various syndromes such as hereditary hemorrhagic telangiectasia, Parkes-Weber, RASA1, CLOVES, and spinal arteriovenous metameric syndromes. Histogenetic analyses revealed a specific distribution of each ID-SAVS in the 5 histogenetic units of the spinal cord: intramedullary niduses were found almost equally from cervical to thoracic units, while MAVFs and mAVFs were mostly found from thoracic to postcrural ones. Pial niduses showed intermediate features between intramedullary and fistulous lesions and were mostly distributed from brachial to crural segments. CONCLUSIONS Precise analysis of the anatomical disposition of ID-SAVSs in relation to functional histogenetic units allows a better understanding of these lesions and improved therapeutic management.

Background /Objective: Recent studies have suggested that a recanalization grade of modified Thrombolysis in Cerebral Infarction (mTICI) score ≥2c is strongly related with good clinical outcome rather than the current therapeutic angiography target ≥2b. To achieve better recanalization, additional further maneuvers on distal residual vessel occlusion (RVO) may be required. The aim of this study was to evaluate the safety and efficacy of rescue treatment in RVOs after recanalization of large vessel occlusions in the anterior circulation. Methods: A single-center retrospective review of a prospectively maintained stroke databank was performed. Patients presenting with RVOs after mechanical thrombectomy on the M1/internal carotid artery terminus were included and further divided into treated and untreated groups: the former underwent additional maneuvers on RVOs, whereas the latter did not. Baseline and posttreatment clinical, radiologic, and angiographic data were compared between the 2 groups. End points included good functional outcome (modified Rankin Scale [mRS] score ≤2) rates of hemorrhagic transformations, neurologic deterioration and mortality. Results: RVOs were observed in 183/488 patients (37.5%). 74/183 (40.4%) underwent rescue treatment, showing a better outcome in terms of median 24 hours National Institutes of Health Stroke Scale score (13 vs. 18; P < 0001), 24 hours Alberta Stroke Programme Early CT Score (6 vs. 5; P < 0.001) and 3 months mRS score 0–2 (47.3% vs. 33.1%; P = 0.06). Recanalization of the superior (frontal) branch of the middle cerebral artery was particularly critical in terms of outcome. Hemorrhagic transformation was higher in the untreated group (53.6% vs. 66.6%; P = 0.1) as well as symptomatic intracranial hemorrhage (13.1% vs. 29.4%; P = 0.01). Neurologic deterioration occurred more often among untreated patients (16.2% vs. 25.7%; P = 0.1). Three complications (1.3%) occurred during rescue treatment. Conclusions: When feasible, improving mTICI score 2a-2b recanalization to mTICI 2c/3 is safe and associated with a better clinical outcome, particularly for residual occlusions involving the superior branch of bifurcation.

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.

Purpose: Bridging veins (BVs) serve as a route of pial venous reflux, and its anatomy is essential to understand the pathophysiology of dural arteriovenous shunts (dAVSs) around the craniocervical junction (CCJ) (from the jugular foramen level to the atlantal level). However, the anatomical variations of the BVs and their proximal connections remained poorly elucidated. This study aimed to radiologically investigate the anatomy of the bridging veins around CCJ and discuss the clinical significance of these BVs in the dAVS. Methods: We investigated normal venous anatomy of the BVs from the jugular foramen level to the atlantal level using preoperative computed tomography digital subtraction venography in patients undergoing elective neurosurgery. BVs affected by the dAVSs in the same region were also evaluated. The three types of dAVS, craniocervical junction, anterior condylar, and proximal sigmoid sinus, were investigated. Results: We identified six BV groups: superolateral, anterolateral, lateral, posterior, inferolateral, and inferoposterior. The superolateral and inferolateral groups, connected with the proximal sigmoid sinus and suboccipital cavernous sinus, respectively, were the largest groups. Each group has a specific downstream venous connection. The association with dVASs was observed only in the inferolateral group, which was typically the sole venous drainage in most dAVSs at the CCJ. Conclusion: We reported detailed anatomy of BVs from the jugular level to the atlantal level, which enhanced our understanding of the pathophysiology of dAVSs in the corresponding region.

Purpose: Although the craniocervical junction has a complex anatomical structure associated with clinical diseases, its ventral venous network has not been well studied. This study aimed to clarify the extracranial ventral venous structure at the craniocervical junction. Methods: Head computed tomography digital subtraction venography (CT-DSV) images of 273 patients (age 6 months to 93 years) taken at our department were retrospectively analyzed. We analyzed the frequency and anatomical features of the venous channels, as well as their upstream and downstream connections with the surrounding channels at the ventral craniocervical junction, from the level of the hypoglossal canal to the second cervical vertebra. Results: In 54% of the cases, the vein descended from the anterior condylar confluence, running medially along the basioccipital and fusing with its counterpart in the midline at the level of the atlanto-occipital membrane. Furthermore, 24% of this vein was connected caudally to the anterior external vertebral venous plexus. We also identified venous channels, either as a sole vein or venous plexus, on the tip of the odontoid process (10%), which has not been well described previously. The vein around the odontoid process was connected to several veins, including the aforementioned vein anterior to the condyle and the anterior internal vertebral venous plexus. Conclusions: CT-DSV analysis revealed a detailed venous architecture ventral to the craniocervical junction. Venous structures identified in this study may be involved in diseases in this area.

Purpose: The venous plexus of Rektorzik (VPR), first described by Rektorzik in 1858, is a venous plexus around the internal carotid artery in the carotid canal. However, the VPR has never been investigated using the recently developed imaging modalities. In this study, we analyzed the VPR using computed tomography-digital subtraction venography (CT-DSV). Methods: This study included 253 patients who had undergone head CT-DSV. The presence or absence of the right and left VPRs and their connecting veins were visually examined by two researchers. Results: The VPR was observed in 60 patients (24%), 39 of which showed VPR only on the right side, 10 only on the left side, and 11 on both sides. VPR was significantly more common on the right side (p = 0.0002) and was observed more frequently around the horizontal segment of the internal carotid artery than around the vertical segment. The most common veins identified as distal and proximal VPR connections were the cavernous sinus (63/71, 89%) and the anterior condylar confluence (27/71, 38%), respectively. The mean age was significantly lower in patients with the VPR than in those without (53 vs. 57 years, p = 0.02). Conclusion: The VPR was significantly more frequent on the right side and in younger patients but was not a radiographically constant structure. In most cases, the VPR connected the cavernous sinus and anterior condylar confluence. Preoperative evaluation of VPR may lead to refined surgical procedures.

Ruptured aneurysms at the craniocervical junction (CCJ) involving the anterior spinal artery (ASA) are rare and consist of heterogenous lesions with variable clinical entities. However, the standard therapeutic strategy for the lesions has not been well-established. Moreover, despite advances in modern neurointervention, reports describing endovascular treatment for this specific lesion have been few. Here, we report three cases of ruptured aneurysms on the pial tributary of the ASA at the CCJ, which were subsequently treated by transarterial glue injection or coil embolization. Endovascular treatment can be a therapeutic option, particularly for these ruptured aneurysms. Either transarterial glue injection or coil embolization can be effective depending on the type of etiology and the surrounding vasculature anatomy.

Abstract Non-syndromic craniosynostosis (NSCS) is a disease, in which a single cranial bone suture is prematurely fused. The early intervention of the disease is associated with a favorable outcome at a later age, so appropriate screening of NSCS is essential for its clinical management. The present study aims to develop a classification and detection system of NSCS using skull X-ray images and a convolutional neural network (CNN) deep learning framework. A total of 56 NSCS cases (scaphocephaly [n = 17], trigonocephaly [n = 28], anterior plagiocephaly [n = 8], and posterior plagiocephaly [n = 3]) and 25 healthy control infants were included in the study. All the cases underwent skull X-rays and computed tomography scan for diagnosis in our institution. The lateral views obtained from the patients were retrospectively examined using a CNN framework. Our CNN model classified the 4 NSCS types and control with high accuracy (100%). All the cases were correctly classified. The proposed CNN model may offer a safe and high-sensitivity screening of NSCS and facilitate early diagnosis of the disease and better neurocognitive outcome for patients.

The authors regret to have forgotten two main authors of the text, Pr Benjamin GORY and Pr Sebastien RICHARD who actively participated with the database of the ETIS Registry and for instance helped in the elaboration of this study. The authors would like to apologise for any inconvenience caused.