The treatment of brain arteriovenous malformations (AVMs) in children has always been a challenge for interventionalists, neurosurgeons, and radiosurgeons. Endovascular embolization is usually performed through transarterial access, but in selected cases the transvenous approach can be considered. The authors of this report aimed to evaluate the efficacy of transvenous embolization in very selected pediatric cases. They describe 4 children treated using transvenous embolization for AVMs that were small, had a single drainage vein, and were deeply located or had a difficult arterial access. The 6-month angiographic and clinical follow-ups are reported as well. In all cases, complete occlusion of the AVM was achieved with no side effects for the patient. Transvenous embolization may represent a promising alternative therapeutic option in very selected cases.
Leonardo Renieri, Nicola Limbucci, Arturo Consoli, Andrea Rosi, Sergio Nappini, Flavio Giordano, Lorenzo Genitori, and Salvatore Mangiafico
Katsuhiro Mizutani, Arturo Consoli, Federico Di Maria, Stéphanie Condette Auliac, Anne Boulin, Oguzhan Coskun, Julie Gratieux, and Georges Rodesch
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.
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.
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.
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.