# Improvement in Hearing Loss Following Posterior Fossa Arachnoid Cyst Fenestration: A Case Study

## TL;DR

A man with hearing loss and headaches showed significant improvement after surgery to treat a brain cyst.

## Contribution

This case study provides evidence of symptom and radiographic improvement following PFAC fenestration.

## Key findings

- Headaches and hearing loss resolved after PFAC fenestration and excision.
- MRI showed decreased cyst size and near-complete syrinx resolution at one-year follow-up.

## Abstract

Arachnoid cysts are abnormal intradural collections of cerebrospinal fluid. For posterior fossa arachnoid cysts (PFACs), symptoms vary greatly, often relating to cranial nerve impingement and/or hydrocephalus. Literature on long-term symptomatic and radiographic follow-up of PFACs is lacking. This case study describes a 32-year-old man who presented with headaches and left-sided hearing loss and was found to have a large left-sided cerebellopontine angle arachnoid cyst with syrinx and ventriculomegaly. After PFAC fenestration and excision, his headaches resolved and his hearing markedly improved. At the one-year postoperative evaluation, symptom improvement persisted, and MRI demonstrated a stable decreased cyst and near-complete resolution of his syrinx.