Evaluation of Disk Halo Size after Implantation of a Collamer Lens with a Central Hole (ICL V4c)
Abstract
Purpose . To investigate disk halo size changes produced by a glare source after surgical insertion of an implantable collamer lens with a central hole (ICL V4c) for myopia correction. Methods . In this prospective study, disk halo size and pupillary light response with a vision monitor were measured preoperatively and at 1 week, 1 month, and 3 months postoperatively. Pupillary light response parameters included contraction amplitude, latency, duration, and velocity; dilation latency, duration, and velocity; and initial, maximum, minimum, and average pupil diameters. Results . Forty-two right eyes of 42 patients were enrolled. Postoperative uncorrected distance visual acuity was better than or equal to 20/20 in all eyes. Compared to preoperative values, disk halo size showed no significant difference at 1 week postoperatively (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mrow><mml:mi>P</mml:mi><mml:mo>></mml:mo><mml:mn>0.05</mml:mn></mml:mrow></mml:math>) and then decreased significantly at 1 and 3 months postoperatively (both <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M2"><mml:mrow><mml:mi>P</mml:mi><mml:mo><</mml:mo><mml:mn>0.001</mml:mn></mml:mrow></mml:math>). Contraction amplitude and velocity, as well as dilation velocity, decreased significantly at all postoperative time points (all <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M3"><mml:mrow><mml:mi>P</mml:mi><mml:mo><</mml:mo><mml:mn>0.001</mml:mn></mml:mrow></mml:math>). Disk halo size at 3 months postoperatively was significantly correlated with initial ( r = 0.446, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M4"><mml:mrow><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.003</mml:mn></mml:mrow></mml:math>), maximum ( r = 0.483, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M5"><mml:mrow><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.001</mml:mn></mml:mrow></mml:math>), minimum ( r = 0.425, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M6"><mml:mrow><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.005</mml:mn></mml:mrow></mml:math>), and average pupil diameters ( r = 0.474, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M7"><mml:mrow><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.002</mml:mn></mml:mrow></mml:math>). Conclusions . After ICL V4c implantation, disk halo size was reduced in the short term. Patients with smaller pupil sizes during pupillary response to light experienced smaller halos after ICL V4c implantation.