Peeling

remove the outer covering.

see Tentorial peeling

A 2-layered arachnoid structure interposes the great vein of Galen (GVG) from above and below the tentorium. The arachnoid membrane below the tentorium can be peeled off bluntly from the GVG to the attachment bundle limited by the penetrating veins. This detachment technique is useful for safe enlargement of the surgical field for the occipital transtentorial approach (OTA) 1)

1)
Miyake S, Suenaga J, Nakamura T, Akimoto T, Suzuki R, Ohtake M, Takase H, Tateishi K, Shimizu N, Murata H, Funakoshi K, Sawamura Y, Yamamoto T. Practical Arachnoid Anatomy for the Technical Consideration of Galen Complex Dissection: Cadaveric and Clinical Evaluation. World Neurosurg. 2021 Jul;151:e372-e378. doi: 10.1016/j.wneu.2021.04.041. Epub 2021 Apr 19. PMID: 33887497.