“Etiology of trichiasis/distichiasis and its management with CO2 laser ablation”

Many techniques have been used to treat trichiasis/distichiasis, but none of them are consistently successful, without complications, or effective in different severities. Additionally, etiologic factors and their relationship with the severity or prognosis has not been identified in non-trachoma-endemic area.In this retrospective consecutive study, we enrolled patients with trichiasis or distichiasis who had undergone CO2 laser ablation in our tertiary medical center between November 2013 and May 2022. Surgical success was defined as no regrowth of misdirected eyelashes for at least 3 months postoperatively. We recorded the success rate within three months and one year after one treatment session, and within three treatment sessions. We also investigated the relationship between etiologic factors, severity, and the success rate.We enrolled 216 eyelids of 137 patients (average age: 69.4 years, mean follow-up durations: 22.9 months). The major underlying causes of trichiasis/distichiasis were idiopathic (64.4%) and prior eyelid surgery (20.8%). More major trichiasis/distichiasis was observed among patients aged <60 years than that in patients aged ≥60 years (43% vs. 21%, p<0.01), and among patients with an underlying cause of prior eyelid surgery compared to patients with idiopathic etiology (42.2% vs. 23.0%, p<0.01). The success rates within three months and within one year after one treatment session, and within three treatment sessions were 87.5%, 76.2%, and 94.4%.Our study demonstrated idiopathic etiology and prior eyelid surgery are common causes of trichiasis/distichiasis. CO2 laser ablation is a safe, effective, and efficient treatment modality.