Suboccipital Craniotomy in the Presence of Extremely Low Torcular Herophili

The torcular herophili is a crucial anatomical landmark in suboccipital craniotomy, dictating the surgical exposure area. Variability in the location of the torcular can be observed in congenital cranial malformations. This study explores the feasibility of conducting posterior fossa surgery in cases of an extremely low-positioned torcular. A suboccipital craniotomy was performed on a patient with an extremely low torcular, without any associated cranial malformations. A left cerebellar hemisphere tumor was accessed through the narrow space (20 mm) between the low torcular and foramen magnum. The left cerebellar hemisphere tumor was totally resected. The patient experienced a favorable postoperative course with no complications. Significant variability in the location of the torcular can appear in patients without cranial malformation. This is the first report demonstrating the applicability of suboccipital craniotomy in patients with an extremely low torcular.