Related Experiment Video
Updated: Jan 28, 2026

Microscopic Cyst Resection for the Treatment of Patients Diagnosed with Epididymal Cyst
Published on: March 31, 2023
Surgical Resection of a Recurrent Intramedullary Spinal Epidermoid Cyst: 2-Dimensional Operative Video
Noah Nichols1, Ketan Yerneni, Joseph A Osorio1
1Department of Neurological Surgery, UCSF Medical Center, San Francisco, California.
Abstract:
Intramedullary spinal epidermoid cysts are rare tumors and only account for 1% of all spinal tumors in adults. Epidermoid cysts can develop from ectodermal tissue that was inappropriately positioned in the primitive neural tube during closure; acquired forms exist for epidermoid cysts as they can emerge in an iatrogenic manner following repeated lumbar punctures. Malignant progression of epidermoid cysts is extremely rare, and symptoms typically depend on tumor location. Surgical resection is the preferred treatment. Gross total resection is ideal; however, partial resections have demonstrated satisfactory long-term outcomes. We present a 54-yr-old man with symptomatic recurrence of thoracic intramedullary epidermoid cyst after two prior resections (25 yr and 11 yr ago, respectively). The patient noted worsening back pain, leg spasticity and weakness. Magnetic resonance imaging (MRI) of the thoracic spine demonstrated interval expansion of the upper thoracic intramedullary epidermoid cyst compared to surveillance MRI from 3 yr prior. Given the progressive nature of symptoms, the patient elected to have surgical resection of the tumor. This operative video highlights the technique and surgical nuances of gross-total resection of a recurrent thoracic intramedullary spinal epidermoid cyst. This patient was noted to have a stable neurological exam at the 6-mo follow-up visit with planned adjuvant radiation treatment. There is no identifying information in this video. Patient consent was obtained for publishing of the material included in the video.
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