Assessment of Change in Pupil Diameter After Muller Muscle Conjunctival Resection Surgery

Purpose: The objective of this study is to evaluate the effect of Muller Muscle Conjunctival Resection (MMCR) surgery on patient pupil diameter in cases of ptosis under different lighting conditions. Material and Methods: In 2017, a study was conducted on a cohort of 34 patients who underwent oculoplasty at the Health Sciences University Beyoglu Eye Training and Research Hospital. The study encompassed a detailed evaluation of preoperative, postoperative 1st and 3th scotopic, mesopic, and photopic pupil diameters. The study also encompassed a comprehensive evaluation of uncorrected visual acuity, best corrected visual acuity, autorefractometry, a biomicroscopic examination, intraocular pressure measurement with a Goldman tonometer, margin reflex distance-1(MRD-1), levator function, eye movements, diplopia test, lagophthalmos and Bell's phenomenon. The study also noted any peroperative and postoperative complications. Results: The present study comprised 34 eyes from 34 patients. The patient population was predominantly female (59%), with 20 (59%) of the patients undergoing right eyelid surgery and 14 (41%) undergoing left eyelid surgery. The etiology of ptosis was categorised as follows: congenital ptosis 28 patients (82%), involutional ptosis 4 patients (12%) and neurogenic ptosis 2 patients (6%). All surgical procedures were performed by a single surgeon (K.F.). The mean levator function was measured to be 16.05 ± 2.32 mm. The MRD-1 (mm) values were 2.35 ± 19 in the preoperative period, 3.52 ± 0.17 in the first postoperative month and 3.82 ± 0.15 in the third postoperative month. A statistically significant increase in MRD-1 values was observed in the postoperative period (p<0.05). One eyelid with inadequate correction underwent subsequent levator surgery. No statistically significant difference was observed between preoperative and postoperative photopic, mesopic and scotopic pupil diameters (p>0.05). However, a postoperative increase in pupil diameter was observed in the photopic condition, and a decrease in the mesopic and scotopic conditions at one month after surgery. Conclusions: The MMCR did not cause a significant alteration in the diameter of pupils measured at different light intensities. This situation may have implications for the surgical outcomes of recent refractive and ptosis surgeries, and it is necessary for this to be evaluated in more detail by prospective studies with large patient groups.