Anatomic variation of the vertebral artery: a case involving a persistent first intersegmental artery at C1-C2.

Background: We observed a rare anatomical variation of a persistent first intersegmental vertebral artery in the C1-C2 region in an elderly Chinese male cadaver at Changzhi Medical College. In this case, the vertebral artery, rather than passing through the transverse foramen of the atlas, exits the transverse foramen of C2 and enters the spinal canal at the lower portion of the C1 posterior arch. The original transverse foramen of C1 was filled with connective tissue.

Endoscopic transnasal prelacrimal recess approach via the orbital floor to the infraorbital region: an anatomical study.

Purpose: The aim of this study is to describe the maximum exposure of the infraorbital region via the orbital floor using the transnasal prelacrimal recess approach (PLRA), and to provide an anatomical basis for treating lesions in the infraorbital region.

Methods: Ten freshly injected frozen heads were dissected using the PLRA. The orbital floor was removed along the border of the medial infraorbital quadrangle, and the periorbita was opened to expose the infraorbital region.

Extended endoscopic endonasal approach to the chiasmatic cistern: An anatomical study of the arachnoid.

This paper studied the arachnoid of the chiasmatic cistern (CC) and the methods for increasing the exposure of the CC from an endoscopic perspective. Eight anatomical specimens with vascular injection were used for endoscopic endonasal dissection. The anatomical characteristics of the CC were studied and documented, and anatomical measurements were collected.