Postoperative Outcomes of Phenylephrine-Guided Müller Muscle-Conjunctival Resection Under General Anesthesia and Sedation Analgesia

Background and Aims: Müller muscle-conjunctival resection (MMCR) is commonly planned based on the preoperative phenylephrine response. We compared postoperative eyelid height, symmetry, and surgical success following phenylephrine-guided MMCR performed under general anesthesia (GA) or sedation analgesia (SA).
Methods: This retrospective comparative study included 60 adults who underwent MMCR at a tertiary oculoplastic center between January 2019 and December 2022 (GA, n=30; SA, n=30). The same phenylephrine-guided resection algorithm was applied in both groups. Margin reflex distance-1 (MRD-1), levator function, resection amount, eyelid symmetry, lagophthalmos, and revision were evaluated through postoperative month 6. Repeated MRD-1 measurements were analyzed using linear mixed-effects models.
Results: Age, sex, and measured baseline ophthalmologic variables were comparable between the groups; etiologic distributions are reported descriptively. Operated-eye MRD-1 improved over time (p=0.042), whereas neither the group-by-time interaction (p=0.565) nor the overall group effect (p=0.287) was statistically significant. At month 6, the mean operated-eye MRD-1 was 3.50±1.04 mm in the SA group and 2.93±0.94 mm in the GA group; the 0.57-mm difference was below the prespecified exploratory threshold of 1 mm. Surgical success was achieved in 93.3% of patients in both groups. Transient lagophthalmos occurred in one patient in each group, and one patient in the GA group required revision.
Conclusion: With identical preoperative phenylephrine-guided planning, no statistically significant between-group differences were observed in postoperative MRD-1 trajectories, and high rates of eyelid symmetry were achieved in both groups. These exploratory findings support protocol consistency across selected anesthesia settings but do not establish equivalence or an independent effect of anesthesia modality.