Posterior chamber phakic intraocular lens sizing based on iris pigment layer measurements by anterior segment optical
Boris E Malyugin1, Alexander A Shpak1, Dmitry F Pokrovskiy1
1From the Cataract & Implant Surgery Department (Malyugin, Pokrovskiy) and Clinical & Functional Diagnostics Department (Shpak), S. Fyodorov Eye Microsurgery Federal State Institution, Moscow, Russia.
Purpose:
To use anterior segment optical coherence tomography (AS-OCT) to evaluate the clinical effectiveness of Implantable Collamer Lens posterior chamber phakic intraocular lens (PC pIOL) sizing based on measurement of the distance from the iris pigment end to the iris pigment end.
Setting:
S. Fyodorov Eye Microsurgery Federal State Institution, Moscow, Russia.
Design:
Evaluation of diagnostic test or technology.
Methods:
Stage 1 was a prospective study. The sulcus-to-sulcus (STS) distance was measured using ultrasound biomicroscopy (UBM) (Vumax 2), and the distance from iris pigment end to iris pigment end was assessed using a proposed AS-OCT algorithm. Part 2 used retrospective data from patients after implantation of a PC pIOL with the size selected according to AS-OCT (Visante) measurements of the distance from iris pigment end to iris pigment end. The PC pIOL vault was measured by AS-OCT, and adverse events were assessed.
Results:
Stage 1 comprised 32 eyes of 32 myopic patients (mean age 28.4 years ± 6.3 [SD]; mean spherical equivalent [SE] -13.11 ± 4.28 diopters [D]). Stage 2 comprised 29 eyes of 16 patients (mean age 27.7 ± 4.7 years; mean SE -16.55 ± 3.65 D). The mean STS distance (12.35 ± 0.47 mm) was similar to the mean distance from iris pigment end to iris pigment end distance (examiner 1: 12.36 ± 0.51 mm; examiner 2: 12.37 ± 0.53 mm). The PC pIOL sized using the new AS-OCT algorithm had a mean vault of 0.53 ± 0.18 mm and did not produce adverse events during the 12-month follow-up. In 16 of 29 eyes, the PC pIOL vault was within an optimum interval (0.35 to 0.70 mm).
Conclusion:
The new measurement algorithm can be effectively used for PC pIOL sizing.
Financial Disclosure:
No author has a financial or proprietary interest in any material or method mentioned.
