Management strategies and clinical outcomes for thalamic neuroepithelial cysts: 10-year single center experience

BACKGROUND: Thalamic neuroepithelial cysts are rare benign lesions that occasionally cause neurological morbidity through parenchymal compression or obstruction of cerebrospinal fluid. Due to their rarity, their natural history and optimal surgical management strategies are unclear. We present the largest single-center experience with thalamic neuroepithelial cysts. METHODS: We conducted a retrospective review of patients with thalamic cysts at the Hospital of the University of Pennsylvania (2014-2025). We identified cases through systematic review of CT and MRI imaging reports. We analyzed patient demographics, anatomical localization, clinical presentations, imaging characteristics, surgical approaches, and outcomes. RESULTS: We identified seven patients with thalamic neuroepithelial cysts (mean age 46.1 ± 16.1 years, 71% female, mean cyst size 2.7 ± 0.6 cm). Three patients (43%) had hydrocephalus. Five cysts (71%) involved the right thalamus, two (29%) the left. Cysts were classified relative to the internal medullary lamina: six (86%) were posteromedial and one (14%) was posterolateral, with 86% showing midbrain extension. Two patients underwent observation. Three patients underwent endoscopic fenestration with third ventriculostomy, achieving complete or near-complete symptom resolution without complications. One patient underwent suboccipital craniotomy for posterior fenestration with excellent recovery, and one received cystoperitoneal shunt placement with successful cyst decompression. CONCLUSIONS: Thalamic neuroepithelial cysts predominantly affect the posterior thalamus with frequent midbrain extension and can be classified as posteromedial or posterolateral relative to the internal medullary lamina, which guides surgical approach. Endoscopic fenestration is safe and effective for symptomatic lesions accessible via natural corridors. Asymptomatic cysts with benign imaging can be managed conservatively.