Position of myopic iris-claw phakic intraocular lens by Scheimpflug photography and ultrasound biomicroscopy

Purpose To evaluate the position of iris-claw phakic intraocular lens (ICPIOL) in highly myopic eyes by Scheimpflug photography (SP) and ultrasound biomicroscopy (UBM). Methods Nine eyes of five patients aged 31 +/- 10 years with average spherical equivalent of -16.04 +/- 5.46D (range -7.88 to -22.88 D) were enrolled in this prospective study and implanted with Verisyse ICPIOLs (AMO). The anterior segment was evaluated by SP and UBM preoperatively and for at least 1 month postoperatively. The statistical significance may be questionable due to the limited number (nine) of eyes. Results By SP and UBM, the distance between corneal endothelium and lens (anterior chamber depth) preoperatively was 3.10 +/- 0.14 and 3.07 +/- 0.11 mm, respectively; between ICPIOL and corneal endothelium (pseudo-anterior chamber depth), 1.88 +/- 0.09 and 1.99 +/- 0.12 mm, respectively; between lens and posterior surface of ICPIOL (IL), 0.76 +/- 0.13 and 0.67 +/- 0.06 mm, respectively; between superior optic edge and iris (SOEI), 0.23 +/- 0.23 and 0.58 +/- 0.24 mm, respectively; between inferior optic edge and iris (IOEI), 0.07 +/- 0.13 and 0.41 +/- 0.22 mm, respectively; between ICPIOL haptics and the angle of anterior chamber (HA), 0.90 +/- 0.17 and 1.45 +/- 0.13 mm, respectively. ACD was well correlated between the two methods, but PACD, IL, OEI, HA were not. The postoperative measures, except IL, were significantly different between the two methods. Conclusion The differences between measurements by SP and UBM reveal the ICPIOL's position variations with change of body position. Nevertheless, it seems adequate that space is maintained between ICPIOL and corneal endothelium, angle, and crystalline lens. The ICPIOL implanted in phakic eyes seems a safe alternative for treatment of high myopia.