Prospective study of blepharoptosis after plaque radiotherapy.

Objective: To prospectively describe the degree of blepharoptosis among patients who underwent plaque radiotherapy.

Design: A single-center prospective cohort study.

Participants: Patients who underwent plaque radiotherapy at a single center.

Methods: Margin reflex distance 1 (MRD1), palpebral fissure height, eyelid excursion, and exophthalmometry measurements were taken before and after surgery. To determine the impact of surgical manipulation versus radiation exposure, measurements were compared to a separate cohort of 28 patients who underwent filtering glaucoma surgery.

Results: There were 24 patients treated with plaque radiotherapy in the study, with a mean age of 61 years at presentation and 70.8% male sex. In involved eyes, mean palpebral fissure height decreased from 8.38 mm preoperatively to 7.25 mm postoperatively (p < 0.01) and mean MRD1 decreased from 3.46 mm to 2.29 mm (p < 0.01). Frequency of ptosis increased from 20.8% preoperatively to 62.5% postoperatively. In a similarly aged cohort of patients undergoing glaucoma filtering surgery, the frequency of ptosis also increased from 32.1% preoperatively to 64.3% postoperatively. The frequency was not different between the plaque and glaucoma groups preoperatively (p = 0.359) or postoperatively (p = 0.894). The degree of ptosis in patients who underwent plaque radiotherapy was similar to patients who underwent glaucoma surgery.

Conclusions: Blepharoptosis is a frequent side effect of plaque radiotherapy, with more than half of patients affected after surgery. When compared to similar surgical manipulation for filtering glaucoma surgery, radiation did not appear to be associated with more frequent blepharoptosis. Patients should be advised that blepharoptosis can be a side effect following plaque radiotherapy.