Trachoma

When a cohort of individuals with trachomatous scarring was followed over 12 years, 6% were found to have developed trichiasis, and 3% had corneal visual impairment.[6]Bowman RJ, Jatta B, Cham B, et al. Natural history of trachomatous scarring in the Gambia: results of a 12-year longitudinal follow-up. Ophthalmology. 2001 Dec;108(12):2219-24. http://www.ncbi.nlm.nih.gov/pubmed/11733262?tool=bestpractice.com

Approximately 50% of those with trichiasis will develop corneal opacity within 2 years if left untreated. Corneal opacity that affects the center of the cornea will result in permanent visual loss. Trichiasis can be painful and the constant abrasion on the cornea can lead to secondary corneal infections.

Post posterior lamellar tarsal rotation surgery

Patients who have had surgery for trichiasis are at a continued risk of recurrence. Posterior lamellar tarsal rotation surgery is associated with significantly lower rates of recurrence than bilamellar tarsal rotation surgery.[63]Habtamu E, Wondie T, Tadesse Z et al. Posterior lamellar versus bilamellar tarsal rotation surgery for trachomatous trichiasis: Long-term outcomes from a randomised controlled trial. EClinicalMedicine. 2019 Nov 1 [Epub ahead of print]. https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(19)30201-9/fulltext ​

As surgery only corrects the architecture of the eyelid but does not alter the pathologic process, which may continue, some degree of recurrence is probably inevitable due to the natural history of trachomatous trichiasis and the ongoing scarring of the tissue.