Morphological, Clinical, and Procedural Determinants of Embolization Outcomes in Non-Cavernous Cerebral Dural Arteriovenous Fistulas: A Retrospective Study

Purpose The purpose of this retrospective study was to determine whether dAVF (dural arteriovenous fistula) characteristics influences treatment indication, embolization techniques, complications, radiation burden, and outcome. Methods and Materials Patients treated by embolization for a brain dAVF were included. Excluded were cavernous sinus and surgically treated dAVF. Patients' demographics, clinical and treatment data were retrieved. dAVF clusters were formed: haemorrhagic versus non-haemorrhagic onset and sinus versus non-sinus type and impact on treatment indication, complications, radiation burden, functional and angiographic outcome was analyzed. Results In a study involving 119 dAVF in 115 patients, 33 patients (mean age 62 years ± 1.8, 72.7% males) presented with a haemorrhagic onset, while 82 (mean age 58 years ± 1.6, 57.3% females) exhibiting 86 dAVF had no bleeding. The sigmoid sinus was over-represented in the latter (52.3%), whereas a cerebrocortical occipital vein was frequently involved in the former group (27,3%). All but one haemorrhagic dAVF demonstrated a Borden-III classification. At six months, the prevalence of mRS class "0" was significantly higher in the non-haemorrhagic dAVF group (70.7% versus 32.3%) compared to the sinus-type clusters, where no such difference was observed. Six months angiography revealed occlusion in 88.2% of 102 catheterized fistulae, similar for all groups. Onyx volume and injection time was significantly higher in non-haemorrhagic and sinus-type dAVF. In non-haemorrhagic dAVF, fluoroscopy time (66.16 versus 40.48 minutes) and the number of acquisitions (68 versus 50) was significantly higher, but not radiation exposure. Although rare, mortality occurred only in sinus-type non-haemorrhagic dAVF. Facial nerve palsy was the major adverse event in non-haemorrhagic dAVF. Conclusion Employing comparable techniques, occluding non-haemorrhagic onset dAVF takes longer and requires a larger embolic volume, yet it presents a higher likelihood of achieving an excellent functional outcome. Occlusion rates are high in all dAVF clusters. Managing non-haemorrhagic, sinus-type dAVFs requires careful attention.