Falcotentorial dAVF with Unusual Venous Drainage Presenting with Obstructive Hydrocephalus: A Case Report and Literature Review of Endoscopic Third Ventriculostomy Followed by Staged Transarterial Embolization.

OBJECTIVE

This study aimed to report a case of falcotentorial dural arteriovenous fistula (dAVF) presenting with obstructive hydrocephalus caused by an unusual venous drainage pattern and to describe a staged treatment strategy.

CASE PRESENTATION: A 38-year-old man presented with photopsia and was found to have obstructive hydrocephalus. MRI demonstrated compression of the cerebral aqueduct by a dilated draining vein. DSA revealed a falcotentorial dAVF with deep venous reflux, supplied by multiple arterial feeders. Venous drainage occurred through a dilated trans-mesencephalic venous pathway, which compressed the cerebral aqueduct, resulting in obstructive hydrocephalus. Because hydrocephalus was present and embolization was considered to carry a risk of worsening obstruction of the cerebral aqueduct, endoscopic third ventriculostomy (ETV) was performed as the initial treatment. After improvement of hydrocephalus, staged transarterial embolization was successfully performed. At 6-month follow-up, DSA showed a small recurrent shunt without clinical deterioration, and the patient remained symptom-free.

CONCLUSION

Falcotentorial dAVF can cause obstructive hydrocephalus depending on venous drainage patterns. When deep venous structures compress the cerebral aqueduct, careful evaluation of venous anatomy and a staged treatment approach, including initial ETV, may be useful for safe management.