Paralytic ectropion usually follows CN VII paralysis or palsy. Typically, concomitant upper eyelid lagophthalmos is present secondary to paralytic upper eyelid orbicularis dysfunction. Poor blinking and eyelid closure lead to chronic ocular surface irritation from corneal exposure, as well as inadequate tear film replenishment and distribution. Chronically stimulated reflex tear secretion, atonic eyelids, and lacrimal pump failure account for the frequent reports of tearing in these patients.
Figure 12-23 Tarsorrhaphy. A, The eyelid is split 2–3 mm deep. B, Epithelium is carefully removed along the upper and lower eyelid margins; the lash follicles are avoided. C, The raw surfaces are then joined with absorbable sutures.
(Illustration by Mark Miller.)
Neurologic evaluation may be needed to determine the cause of the CN VII paralysis. In cases resulting from stroke or intracranial surgery, clinical evaluation of corneal sensation is indicated because neurotrophic keratopathy combined with paralytic lagophthalmos increases the risk of corneal decompensation.
Lubricating drops, viscous tear supplementation, ointments, taping of the temporal half of the lower eyelid, or moisture chambers can be used. Such measures may be the only treatment necessary, especially for temporary paralysis. In select patients with long-term or permanent paralysis, tarsorrhaphy, medial or lateral canthoplasty, suspension procedures, and horizontal tightening procedures are useful.
Tarsorrhaphy can be performed either medially or laterally. An adequate temporary tarsorrhaphy (1–3 weeks) can be achieved with placement of nonabsorbable sutures between the upper and lower eyelid margins. A “temporary tarsorrhaphy” can also be created by injection of botulinum toxin into the levator muscle. Permanent tarsorrhaphy involves deepithelialization of the upper and lower eyelid margins, avoiding the lash follicles. Absorbable or nonabsorbable sutures are then placed to unite the raw surfaces of the upper and lower eyelids (Fig 12-23).
Occasionally, a fascia lata or silicone suspension sling of the lower eyelid may be indicated. Vertical elevation of the lower eyelid is useful in reducing exposure of the inferior cornea. This elevation may be accomplished through recession of the lower eyelid retractors, combined with use of a spacer graft. Surgical midface elevation can also play an important role in lower eyelid support.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.