Sasikhan Geibprasert, Vitor Pereira, Timo Krings, Pakorn Jiarakongmun, Pierre Lasjaunias and Sirintara Pongpech
The goal in this study was to present possible pathological mechanisms, clinical and imaging findings, and to describe the management and outcome in patients with hydrocephalus due to unruptured pial brain arteriovenous malformations (AVMs).
Medical records and imaging findings in 8 consecutive patients with hydrocephalus caused by AVMs and treated between June 2000 and September 2007 were retrospectively reviewed to determine clinical symptoms, AVM location, venous drainage, level/cause of obstruction, and degree of hydrocephalus. Management of hydrocephalus, AVM treatment, complications, and follow-up results were evaluated.
Headaches were the most common clinical symptom (7 of 8 patients). Deep venous drainage was identified in all patients. Mechanical obstruction by the draining vein or the AVM nidus was seen in 6 patients, in whom obstruction occurred at the interventricular foramen (2 patients) or the aqueduct (4 patients). Hydrodynamic disorders following venous outflow obstruction and venous congestion of the posterior fossa led to hydrocephalus in the remaining 2 patients. Ventriculoperitoneal (VP) shunts were placed in 6 of 8 patients with a moderate to severe degree of hydrocephalus. Regression of hydrocephalus was noted in 4 patients, whereas in 2 the imaging findings were stable, 1 of whom had decreased hydrocephalus only after AVM size reduction. In 2 patients with mild hydrocephalus who were not treated with shunt insertion, 1 improved and 1 was clinically stable after AVM treatment.
The most common cause of hydrocephalus in unruptured brain AVMs is mechanical obstruction by the draining vein if it is located in a strategic position. Management should be aimed at treatment of the AVM; however, VP shunts may be necessary in acute and severe cases of hydrocephalus.
Yutaka Mitsuhashi, Thaweesak Aurboonyawat, Vitor Mendes Pereira, Sasikhan Geibprasert, Frédérique Toulgoat, Augustin Ozanne and Pierre Lasjaunias
Dural arteriovenous fistulas (DAVFs) with leptomeningeal venous reflux generally pose a high risk of aggressive manifestations including hemorrhage. Among DAVFs, there is a peculiar type that demonstrates direct drainage into the bridging vein rather than the dural venous sinus. The purpose of this study was to investigate the characteristics of DAVFs that drain directly into the petrosal vein or the bridging vein of the medulla oblongata.
Eleven consecutive cases of DAVFs that drained directly into the petrosal vein and 6 that drained directly into the bridging vein of the medulla were retrospectively reviewed. These cases were evaluated and/or treated at Hospital de Bicêtre in Paris, France, over a 27-year period. A review of previously reported cases was also performed.
Both of these “extrasinusal”-type DAVFs demonstrated very similar characteristics. There was a significant male predominance (p < 0.001) for this lesion, and a significantly higher incidence of aggressive neurological manifestations including hemorrhage or venous hypertension than in DAVFs of the transverse-sigmoid or cavernous sinus (p < 0.001). This finding was considered to be attributable to leptomeningeal venous reflux. Regarding treatment, endovascular embolization (either transarterial or transvenous) is frequently difficult, and surgery may be an effective therapeutic choice in many instances.
Embryologically, both the petrosal vein and the bridging vein of the medulla are cranial homologs of the spinal cord emissary bridging veins that drain the pial venous network. The authors believe that DAVFs in these locations may be included in a single category with spinal DAVFs because of their similar clinical characteristics.
Giuseppe Lanzino and Edoardo Boccardi
Hengwei Jin, Stephanie Lenck, Timo Krings, Ronit Agid, Yibin Fang, Youxiang Li, Alex Kostynskyy, Michael Tymianski, Vitor Mendes Pereira and Ivan Radovanovic
The goal of this study was to describe changes in the angioarchitecture of brain arteriovenous malformations (bAVMs) between acute and delayed cerebral digital subtraction angiography (DSA) obtained after hemorrhage, and to examine bAVM characteristics predicting change.
This is a retrospective study of a prospective institutional bAVM database. The authors included all patients with ruptured bAVMs who had DSA in both acute and delayed phases, with no interval treatment of their bAVM, between January 2000 and April 2017. The authors evaluated the existence or absence of angioarchitectural changes. Demographic data, radiological characteristics of hemorrhages, and angioarchitectural features of the bAVMs of the two patients’ groups were analyzed. Univariate and multivariate logistic analyses were performed to identify predictors of angioarchitectural change.
A total of 42 patients were included in the series. Seventeen (40.5%) patients had angioarchitectural changes including bAVM only visible on the delayed DSA study (n = 8), spontaneous thrombosis of the AVM (n = 3), or alteration of the size or the opacification of the nidus (n = 6). The factors associated with angioarchitectural changes were a small nidus (3.8 ± 7.9 ml vs 6.1 ± 9.5 ml, p = 0.046), a superficial location (94.1% vs 5.9%, p = 0.016), and a single superficial draining vein (58.8% vs 24.0%, p = 0.029).
Angioarchitectural changes can be seen in 40% of ruptured bAVMs between the acute- and delayed-phase DSA. A small nidus, a superficial location, and a single superficial draining vein were statistically associated with the occurrence of angioarchitectural changes. These changes included either enlargement or spontaneous occlusion of the bAVM, as well as subsequent diagnosis of a bAVM following an initial negative DSA study.
Christoph J. Griessenauer, Christopher S. Ogilvy, Nimer Adeeb, Adam A. Dmytriw, Paul M. Foreman, Hussain Shallwani, Nicola Limbucci, Salvatore Mangiafico, Ashish Kumar, Caterina Michelozzi, Timo Krings, Vitor Mendes Pereira, Charles C. Matouk, Mark R. Harrigan, Hakeem J. Shakir, Adnan H. Siddiqui, Elad I. Levy, Leonardo Renieri, Thomas R. Marotta, Christophe Cognard and Ajith J. Thomas
Flow diversion for posterior circulation aneurysms performed using the Pipeline embolization device (PED) constitutes an increasingly common off-label use for otherwise untreatable aneurysms. The safety and efficacy of this treatment modality has not been assessed in a multicenter study.
A retrospective review of prospectively maintained databases at 8 academic institutions was performed for the years 2009 to 2016 to identify patients with posterior circulation aneurysms treated with PED placement.
A total of 129 consecutive patients underwent 129 procedures to treat 131 aneurysms; 29 dissecting, 53 fusiform, and 49 saccular lesions were included. At a median follow-up of 11 months, complete and near-complete occlusion was recorded in 78.1%. Dissecting aneurysms had the highest occlusion rate and fusiform the lowest. Major complications were most frequent in fusiform aneurysms, whereas minor complications occurred most commonly in saccular aneurysms. In patients with saccular aneurysms, clopidogrel responders had a lower complication rate than did clopidogrel nonresponders. The majority of dissecting aneurysms were treated in the immediate or acute phase following subarachnoid hemorrhage, a circumstance that contributed to the highest mortality rate in those aneurysms.
In the largest series to date, fusiform aneurysms were found to have the lowest occlusion rate and the highest frequency of major complications. Dissecting aneurysms, frequently treated in the setting of subarachnoid hemorrhage, occluded most often and had a low complication rate. Saccular aneurysms were associated with predominantly minor complications, particularly in clopidogrel nonresponders.