Surgical Obliteration of a Filum Terminale Arteriovenous Fistula Following Aborted Endovascular Embolization: Illustrative Case Report and Literature Review

Arteriovenous fistulas of the filum terminale are rare vascular malformations that predominantly affect males and can present with various neurological symptoms. In this study, we indexed previously published cases of filum terminale arteriovenous fistulas demonstrating that endovascular and microsurgical management are both proven to be appropriate and successful treatment modalities with low complication rates. Endovascular treatment is far less invasive; however, it is associated with higher failure rates, which need to be managed surgically. In this case, we report a 64-year-old male patient who presented with lower back pain and bilateral lower extremity weakness. He was found to have a filum terminal arteriovenous fistula causing thoracolumbar spinal cord edema. Following a failed attempt of endovascular embolization complicated by declining neuromonitoring signals, open microsurgical obliteration of the lesion was successfully performed. While endovascular management of filum terminale arteriovenous fistulas is a viable and successful treatment modality in select cases, surgeons should be prepared to manage these cases with an open microsurgical approach should embolization fail or become unsafe. Proper radiologic characterization of the lesion and accurate localization of the location of the fistula are requisites to a safe and successful obliteration of these lesions.