The palpebral part of orbicularis oculi produces the gentle, involuntary blink. Unlike the orbital part (forceful closure), the palpebral part operates during normal blinking at 12-15 times per minute, spreading the tear film and draining tears via the lacrimal pump mechanism.
| Origin | Medial palpebral ligament — both upper and lower eyelid portions |
|---|---|
| Insertion | Lateral palpebral raphe |
| Nerve Supply | Facial nerve — temporal and zygomatic branches (VII) |
| Blood Supply | Palpebral arteries from the ophthalmic artery |
| Actions | Gentle involuntary eye closure — blinking; Lacrimal pump — spreads the tear film across the cornea during blinking |
|---|
The palpebral part is the component assessed in incomplete lid closure (lagophthalmos) — its weakness produces inadequate blink with corneal exposure. In blepharoplasty, the pretarsal palpebral fibres are preserved to maintain blink mechanics. Blepharospasm involves involuntary palpebral part overactivity and is treated by botulinum injection targeting the preseptal and pretarsal palpebral fibres.
Assessed by blink rate and completeness of blink closure — incomplete blink leaves a corneal exposure zone inferiorly.
Incomplete blink from palpebral orbicularis weakness producing inferior corneal punctate epitheliopathy from chronic desiccation, managed by lubricants, taping, and lid weight implantation.
