Microsurgical Resection of a Pineal Cyst via a Paramedian Supracerebellar Infratentorial Approach

Abstract

Pineal cysts are typically detected in around 1.3% to 4.3% of patients during routine MRI scans1,2. The vast majority of pineal cysts are benign, asymptomatic, and typically do not necessitate surgical intervention.Large pineal cysts are known to cause hydrocephalus with its associated symptoms and thus can require in rare cases surgical resection. Even in absence of hydrocephalus, selected patients with large pineal cysts causing headaches and visual disturbances, can find relief after surgical resection3,4.The supracerebellar infratentorial (SCIT) approach is widely used and represents an extraparenchymatous approach through a natural corridor to the pineal region5. Performing this approach in a semi-sitting position allows for an optimal retraction of the cerebellum by gravity. We employ a minimally invasive paramedian SCIT approach for the resection of pineal cysts. In our experience, the paramedian SCIT approach allows for a less steep operating angle and a smaller craniotomy compared to the midline SCIT approach.We present a 24-year-old female complaining of headache. The initial MRI was conducted two years prior to surgery. Following the initial evaluation, the patient experienced progressive headaches without neurological deficits. A subsequent MRI revealed an enlargement of the pineal cyst, leading to the indication for surgical resection.The surgery was performed mainly under the operating microscope with endoscopic visualization in suitable situations as our small approach restricts bimanual dissection with an endoscope. In our experience, this approach provides a versatile and minimally invasive access to the pineal region, making it optimally suitable for pineal cysts requiring surgical resection.