A case of spontaneous brain arteriovenous malformation occlusion: Imaging analysis and clinical debate

The spontaneous occlusion of brain arteriovenous malformations (bAVMs) is a rare event, particularly for unruptured ones. Associated factors include single-venous drainage and small nidus size. Most of the previously reported cases were ruptured bAVMs. We report the case of a middle-aged male patient with an unruptured, rolandic, left-sided bAVM associated with a 30-year history of refractory epilepsy. We documented the spontaneous thrombosis of the venous drainage of the AVM without any sign of bleeding. Finally, we underline the difference between ruptured-induced occlusion and truly spontaneous thrombosis of the bAVMs.

24-Hour Carotid Stent Patency and Outcomes After Endovascular Therapy: A Multicenter Study

BACKGROUND

Management of extracranial internal carotid artery steno-occlusive lesion during endovascular therapy remains debated. Stent occlusion within 24 hours of endovascular therapy is a frequent event after acute carotid artery stenting, and we currently lack large population results. We investigated the incidence, predictors, and clinical impact of stent occlusion after acute carotid artery stenting in current clinical practice.

METHODS

Patients treated by endovascular therapy with acute carotid artery stenting between 2015 and 2019 in 5 large-volume endovascular-capable centers were retrospectively analyzed. Patients were separated in 2 groups according to the stent patency at 24 hours after carotid artery stenting. We compared baseline characteristics, treatment modalities, and clinical outcome depending on 24-hour stent patency. Primary end point was favorable outcome, defined as a modified Rankin Scale score 0-2 at 3 months.

RESULTS

A stent occlusion was observed in 47/225 patients (20.9%). Patients with stent patency had a lower baseline National Institutes of Health Stroke Scale (median [interquartile range]: 13 [7-17] versus 18 [12-21]) and had more often stroke of atherothrombotic origin (77.0% versus 53.2%). A higher stent patency rate was found for patients treated with P2Y₁₂ antagonists at the acute phase (odds ratio [OR]' 2.95 [95% CI' 1.10-7.91]; P=0.026) and treated with angioplasty (OR' 2.42 [95% CI' 1.24-4.67]; P=0.008). A better intracranial angiographic reperfusion was observed in patients with 24-hour stent patency compared with patients without stent patency (OR' 8.38 [95% CI' 3.07-22.78]; P<0.001). Patients with a stent patency at 24 hours had a higher chance of favorable outcome (OR' 3.29 [95% CI, 1.66-6.52]; P<0.001) and a lower risk of death (OR' 0.32 [95% CI, 0.13-0.76]; P=0.009).

CONCLUSIONS

One out of 5 patients treated with carotid artery stenting during endovascular therapy presented a stent occlusion within 24 hours. This event was associated with worse functional outcome. Stroke etiology, P2Y₁₂ antagonist administration, quality of intracranial reperfusion, and angioplasty were associated with 24-hour stent patency.

Sustained Tumor Control With MAPK Inhibition in BRAF V600-Mutant Adult Glial and Glioneuronal Tumors

OBJECTIVE

To assess whether RAF and MEK inhibitors (RAFi/MEKi) can provide long-term clinical benefit in adult patients with BRAF V600-mutant glial and glioneuronal tumors (GGNTs), we analyzed tumor response and long-term outcome in a retrospective cohort.

METHODS

We performed a retrospective search in the institutional databases of 6 neuro-oncology departments for adult patients with recurrent or disseminated BRAF V600-mutant GGNTs treated with RAFi/MEKi.

RESULTS

Twenty-eight adults with recurrent or disseminated BRAF V600-mutant gangliogliomas (n = 9), pleomorphic xanthoastrocytomas (n = 9), and diffuse gliomas (n = 10) were included in the study. At the time that treatment with RAFi/MEKi was started, all tumors displayed radiologic features of high-grade neoplasms. Thirteen patients received RAFi as single agents (vemurafenib [n = 11], dabrafenib [n = 2]), and 15 received combinations of RAFi/MEKi (vemurafenib + cobimetinib [n = 5], dabrafenib + trametinib [n = 10]). Eleven patients achieved a partial or complete response (11 of 28, 39%), with a median reduction of -78% in their tumor burden. Responders experienced a median increase of 10 points in their Karnofsky Performance Status (KPS) score and a median progression-free survival of 18 months, which was longer than achieved with first-line treatment (i.e., 7 months, p = 0.047). Responders had better KPS score (p = 0.018) and tended to be younger (p = 0.061) and to be treated earlier (p = 0.099) compared to nonresponders. Five patients were rechallenged with RAFi/MEKi at progression, with novel tumor responses in 2. On univariate and multivariate analyses, response to RAFi/MEKi was an independent predictor of overall survival.

CONCLUSIONS

Our study highlights the long-term clinical benefits of RAFi/MEKi in adult patients with BRAF V600-mutant GGNTs and encourages rechallenge in responders.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that, for adult patients with BRAF V600-mutant GGNT, RAFi/MEKi can reduce tumor burden and provide clinical benefit.

Intradural spinal cord arteriovenous shunts in a personal series of 210 patients: novel classification with emphasis on anatomical disposition and angioarchitectonic distribution, related to spinal cord histogenetic units

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.

Spinal cord arterio-venous shunts: From classification to therapeutic management

Spinal Cord Arterio-Venous shunts (SCAVSs) are a rare disease. The aim of this paper is to describe how we classify and consider management of SCAVSs in relation to the location of the shunt focusing mainly on intradural SCAVSs. The anatomical features of the SCAVSs together with data provided by MRI and CT scans allow identification of four types of SCAVSs: paraspinal, epidural, dural and intradural ones. Clinical and neuroradiologic characteristics are described for each entity as well as the therapeutic endovascular management at our institution between 2002 and 2020. The therapeutic management of SCAVSs, and in particular of intradural shunts, remains mainly based on endovascular treatment as a first-choice approach. Understanding properly the lesional and regional vascular anatomy is mandatory to plan an appropriate therapeutic strategy and obtain good clinical results stable at long term follow up.

[Therapeutic and endovascular management of cerebral mycotic aneurysms]

Infective endocardites are associated with both ischemic and hemorrhagic neurological complications and also with cerebral abscesses and the development of "mycotic" aneurysms, which are detected in about 5 % of patients in the acute and sub-acute phase of the infection. Data about their natural history and their hemorrhagic risk are scarce and fragmented. The therapeutic management is represented by the medical treatment of the infection with interventional abstention, the surgical treatment and the endovascular approach by selective embolization of the aneurysm. No evidence is provided concerning the superiority of a specific approach. Mycotic aneurysms remain a diagnostic and therapeutic challenge and their management is necessarily based on a multidiscplinary approach.

Impact of Reperfusion for Nonagenarians Treated by Mechanical Thrombectomy

Background and Purpose—

Nonagenarians represent a growing stroke population characterized by a higher frailty. Although endovascular therapy (ET) is a cornerstone of the management of acute ischemic stroke related to large vessel occlusion, the benefit of reperfusion among nonagenarians is poorly documented. We aimed to assess the impact of ET-related reperfusion on the functional outcome of reperfusion in this elderly population.

Methods—

A retrospective analysis of clinical and imaging data from all patients aged over 90 included in the ETIS (Endovascular Treatment in Ischemic Stroke) registry between October 2013 and April 2018 was performed. Association between post-ET reperfusion and favorable (modified Rankin Scale [0–2] or equal to prestroke value) and good (modified Rankin Scale [0–3] or equal to prestroke value) outcome were evaluated. Demographic and procedural predictors of functional outcome, including the first-pass effect, were evaluated. Results were adjusted for center, admission National Institutes of Health Stroke Scale, and use of intravenous thrombolysis.

Results—

Among the 124 nonagenarians treated with ET, those with successful reperfusion had the lowest 90-day modified Rankin Scale (odds ratio, 3.26; 95% CI, 1.04–10.25). Only patients with successful reperfusion after the first pass (n=53, 56.7%) had a reduced 90-day mortality (odds ratio, 0.15; 95% CI, 0.05–0.45) and an increased rate of good outcome (odds ratio, 4.55; 95% CI, 1.38–15.03). No increase in the rate of intracranial hemorrhage was observed among patients successfully reperfused.

Conclusions—

Successful reperfusion improves the functional outcome of nonagenarians who should not be excluded from ET. The first-pass effect should be considered in the procedural management of this frail population.