Introduction: The eyelid transorbital approach for the treatment of middle and anterior cranial fossa lesions has become very prominent in the last years.

Objectives: This work aims to describe a technical nuance that, added to the conventional eyelid transorbital approach, could improve the surgical field of view and working angle when targeting the optic-carotid region.

Methods: Two embalmed adult cadaveric specimens (4 orbits) were used in the study. A transorbital approach was performed in each orbit, with the removal of the anterior clinoid process (ACP) and the lateral orbital rim. Finally, a McCarty’s keyhole was performed in the lateral part of the superolateral orbital wall. Since the frontal dura was already exposed, the keyhole consisted of a lateral extension of the craniectomy.

Results: The extension of the craniectomy to the keyhole area created an additional working channel where a spatula can be positioned for frontal lobe retraction, or the endoscope can be located achieving a better view of the optic-carotid region. The Sylvian fissure was easily handled since gentle retraction of the frontal lobe could be performed. Furthermore, this approach allows to an easier and safer removal of the ACP and no cosmetic defect is created, since the bone defect can be covered by a mini-plate and remains hidden under the temporalis muscle.

Conclusions: Extending the craniectomy performed through the transorbital approach to the McCarty’s keyhole expands the surgical view to the optic-carotid region and improves the maneuverability of the brain to get access to the Sylvian fissure.