Effects of Pupil Size on Functional Outcomes of a Simultaneous Vision Intraocular Lens.

Purpose: To evaluate the relationship between pupil size and subjective visual quality after implantation of a simultaneous vision intraocular lens (IOL).

Methods: Patients after bilateral implantation of a trifocal, diffractive IOL were prospectively included. Three months postoperatively, subjective refraction, UDVA, and axis deviation were measured. Pupil size was obtained with an infrared-based pupillometer (PupilX; Albomed) in scotopic, mesopic, and photopic conditions. Subjective impairment with optical phenomena was surveyed in different lighting conditions.

Results: Fifty-two patients (mean age: 68 years) were included; 54 eyes received non-toric IOLs and 50 eyes received toric IOLs. Preoperative spherical equivalent (SE) was -0.914 diopters (D) (range: -10.00 to +5.92 D) and SE and lens torus were 20.3 D (range: 9.00 to 32.00 D) and 1.65 D (range: 1.00 to 3.75 D), respectively. Three months postoperatively pupil size was 5.42 mm (range: 2.60 to 7.50 mm) in scotopic, 4.24 mm (range: 2.60 to 6.10 mm) in mesopic, and 3.38 mm (range: 1.20 to 5.60 mm) in photopic conditions, spherical manifest refractive error 0.14 D (range: -0.75 to 1.25 D), SE 0.034 D (range: -1.13 to +1.13 D), and UDVA 20/22.4 (range: 20/63 to 20/12.5). In low light conditions, halos correlated weakly with scotopic (r = 0.268, P = .006) and mesopic (r = 0.298, P = .002) pupil size and double-contour with scotopic pupil size (r = 0.234, P = .018). Glare, starbursts, and blurred vision were not influenced in any condition. Further significant influential factors were postoperative spherical manifest refractive error (P = .014), SE (P = .007) and lens torus (P = .029) for halos and preoperative SE (P = .019), postoperative UDVA (P = .035), and lens SE (P = .023) for double-contour. In multiple regression analysis, lens torus, mesopic pupil size, preoperative SE, and postoperative UDVA remained significant.

Conclusions: Pupil size did not play a major role in disturbance with optical phenomena after implantation of a trifocal diffractive IOL. [J Refract Surg. 2025;41(7):e645-e654.].