Palpebral Fissure of the Head

Description

Oblique external anatomy of the male palpebral fissure is presented as the slit-like aperture between the upper and lower eyelids, extending from the medial canthus near the root of the nose to the lateral canthus toward the temporal region. The superior lid margin is positioned anterior to the globe and descends slightly medially, while the inferior lid margin rises gently to meet it at each commissure. At the medial canthus, the caruncula lacrimalis and plica semilunaris would be expected just medial to the fissure, with the lacrimal puncta sitting on the posterior aspect of each lid margin near the canthal angle. Lateral canthal attachments anchor the lid margins to the lateral orbital rim, holding the palpebral fissure in its characteristic horizontal orientation. Small changes in canthal position matter. This view supports teaching and documentation of lid malposition such as ectropion and entropion, where punctal eversion or inversion alters tear drainage and can drive chronic epiphora, exposure keratopathy, or recurrent conjunctivitis. It also frames common oculoplastic procedures, including lateral canthotomy and cantholysis for orbital compartment syndrome, where rapid release at the lateral canthus decompresses the orbit, and blepharoplasty planning that respects the lateral canthal tilt to avoid postoperative rounding. A key surface landmark. Use this illustration in head and neck anatomy courses, ophthalmology and plastic surgery texts, and clinical handouts for eyelid examination, canthal measurements, and preoperative counseling in blepharoplasty or trauma repair. Anatomical accuracy verified by SciePro's Medical Advisory Board.