A 63-year-old male visited the neurosurgery department with a complaint of headache. He was subsequently diagnosed with a suspicious DAVF at the falcotentorial junction on magnetic resonance angiography. Digital subtraction angiography (DSA) demonstrated a Galenic type of TDAVF fed by a branch mimicking the left PCA, which appeared to arise from the top of the basilar artery (
Fig. 1). The TDAVF drained directly into the vein of Galen, with reflux to the basal vein of Rosenthal (BVR), lateral mesencephalic vein, and cavernous sinus. Ectatic changes were observed in the draining veins, suggesting venous hypertension. The left PCA was not indicated on vertebral artery (VA) angiography due to the fetal type PCoA flow from the left internal cerebral artery (ICA). The main feeding artery ran beneath the fetal type PCoA around the midbrain and made an upward turn towards the falcotentorial junction, indicating that it was the ADS [
1,
6,
11]. Additionally, left external carotid artery (ECA) angiography showed another feeder from the branch of the occipital artery (
Fig. 1D).
Under general anesthesia and systemic heparinization, transarterial embolization was performed via the right femoral artery. A 6 French Envoy guiding catheter (Cordis Corporation, Miami Lakes, Florida, USA) was placed in the left VA. A microcatheter (detachable tip microcatheter, Apollo, ev3 Neurovascular, Micro Therapeutics, Inc., USA) was advanced through the catheter over the microwire (Synchro neuro guide wire, Stryker Neurovascular, Kalamazoo, MI, USA) and into the ADS. Access to the distal portion of the ADS was achieved, and the fistula was completely occluded using Onyx 18 (ev3 Neurovascular, Micro Therapeutics, Inc., USA), without any reflux (
Fig. 2A-
C). Postoperative VA angiography showed occlusion of the fistula and revealed that the entire left PCA with P1-PCoA junction, which was not visualized preoperatively due to the high flow of the ADS and fetal type PCoA. Thus, we could confirm the exact origin of the feeder ADS, which was the left P1-PCoA junction and not the top of the basilar artery (
Fig. 2C). Postoperative ECA angiography also demonstrated occlusion of AV shunt (
Fig. 2D). Postoperative magnetic resonance imaging revealed no acute ischemic or hemorrhagic complications, and the patient was discharged after two postoperative days without any neurological problems. Furthermore, a magnetic resonance angiography was performed 12 months later after the treatment for follow-up, no remnant and recurrence of DAVF were observed (
Fig. 2E). Written informed consent was obtained to publish this report.
Literature review: TDAVFs supplied by the ADS
We searched the literature using the PubMed database (until June 2021) to identify studies of DAVFs supplied by the ADS and the type of treatment performed through the endovascular approach. “Artery of Davidoff and Schechter,” “Davidoff and Schechter,” and “tentorial dural arteriovenous fistula” were searched as either keywords or Medical Subject Heading terms. All searched articles and references were reviewed to identify all related studies.
The resulting articles were systematically assessed and included in the review. All studies describing patients with DAVF that was supplied by the ADS and treated with an endovascular approach were included. Cases of additional surgical treatment, radiosurgery, and non-treatment were excluded. All the included articles were in English. Studies with clinical outcomes, complications, and angiographic cure rates of transarterial embolization through the ADS were evaluated and compared with those of other endovascular options.
Six journals of case reports and case series were found, out of which 25 patients were selected after applying the exclusion criteria. After including the patient in this study, a total of 26 patients were reviewed. The total number of endovascular treatment sessions was 32 owing to the multiple embolization sessions performed in a few patients [
1,
4,
8]. Patients’ age, sex, symptoms, DAVF location, feeding arteries, draining veins, Borden classification, number of embolization approach sessions, complications, and angiographic cure are presented in
Table 1 [
1,
4-
6,
8,
12].
Patient age ranged from 30 to 66 years, and the varied symptoms included headache, vomiting, dizziness, tinnitus, hearing loss, exophthalmos, vision loss, and altered mental status. Four patients presented intracranial hemorrhage. Most patients had falcotentorial DAVF (22/26). Numerous feeding arteries were reported, where dural arterial feeders, including the occipital artery, middle meningeal artery, recurrent meningeal artery, and posterior meningeal artery, and pial arterial feeders, including the PCA, VA, superior cerebellar artery, posterior inferior cerebellar artery, meningohypophyseal trunk and ICA, were described. Most of the DAVFs were type III, according to the Borden classification.
Eight of the twenty-six patients underwent transarterial embolization via the ADS [
1,
8,
12]. Angiographic cure rate was 88.4% (23/26) in all patients and 100% (8/8) in the ADS group. One patient had a complication of a brain stem infarction when embolization was performed at the junction of the ADS and PCA [
12]. No complication was reported after embolization via the ADS when distal access was achieved. One patient in the ADS group had a complication of a thalamic infarction and Parinaud syndrome as a result of additional embolization of posterior medial choroidal artery and tactile compression of large thrombosed venous varix [
8]. Byrne and Garcia and Griessenauer et al. reported six cases of endovascular treatment of DAVF fed by the ADS; however, the exact approach route was not described. Moreover, no complications were reported after the embolization sessions in these cases [
4,
6]. Summary of reported cases are presented in
Table 2.