| PART Ⅰ:The Anatomical Structures Changes of Anterior Segment After ICL implantationPURPOSE:To evalute the anterior segment anatomical changes after posterior chamber phakic intraocular lens (Visian ICL V4, Implantable Collamer Lenses V4) implantation for high myopic eyes.METHOD:175eyes of93patients underwent myopic ICL implantation were recruited (age=30.52±7.0years, range from18to48years).119eyes underwent conventional ICL implantation and46eyes underwent Toric-ICL implantation. To evaluated eyes of consecutive patients having ICLs sugery. Preoperative and postoperative (one week) anterior chamber volume (ACV), anterior chamber depth (ACD), anterior chamber angle(ACA)(scan from3-9o’clock), the distance between central posterior surface of the ICL and anterior surface of the crystalline lens (vault), cornea-lens distance, iris-lens distance, spherical equivalent of phakic intraocular lens(pIOL SE) were recorded and analyzed.RESULT:The mean ACV decreased from200.29±31.76mm preoperatively to116.49±21.88mm one week postoperatively (t=48.456, P=0.000), the ACD decreased from3.17±0.23mm (preop) to2.89±0.33mm (1week postop)(t=12.237, P=0.000). The anterior chamber angle decreaed from36.40±4.90°(preop) to23.44±5.07°(1week postop)(t=31.131, P=0.000). Postoperative ACA was positively correlated with postoperative ACV(r=0.637, P=0.000) and postoperative ACD(r=0.393; P=0.000). Postoperative corneal-lens distance were greater than preoperative cornea-lens distance (mean difference0.40±0.31mm; P=0.000). Positive correlation were observed between corneal-lens distance with vault (r=0.446, P=0.000). Stepwise regression analysis showed that the ratio of vault to cornea-lens distance, and the change rate of preoperative and postoperative pupil diameter were two independent predictors of the changes of corneal-lens distance.(P=0.001and P=0.048, respectively)CONCLUSION:ICLs implantation could decrease the size of ACV and narrow the anterior chamber angles. PART Ⅱ:The Effect of Implantable Collamer Lens (ICL) Implantation on Retinal Straylight in High Myopic eyesPURPOSE:To investigate the association between the anterior segment structures change and straylight after Collamer posterior chamber phakic intraocular lens(pIOL) implantation.METHOD:Implantable Collamer lens (ICL) implantation was performed on91eyes (46patients). The anterior segment anatomic parameters and intraocular straylight parameter log(s) were measured using Scheimpflug image photography and C-Quant straylight meter respectively before and after surgery (1week to3months). Correlations were then analyzed between the log(s) and following parameters, such as anterior chamber depth (ACD), plOL spherical equivalent (SE), corrected distant visual acuity (CDVA), pupil size, axial length and ICL vaulting.RESULT:The log(s) decreased from preoperative1.27±0.15units to postoperative1.21±0.14units, but there was no significant statistic difference (P=0.128). Higher postoperative log(s) were found significantly correlated to lower vaulting(r=-0.361; P=0.022), lower ratio of vault to cornea-lens distance(r=-0.444; P=0.004) and lower negative diopters of pIOL SE(r=0.327; P=0.039). Regression analysis showed that the ratio of vault to postoperative cornea-lens distance, and the postoperative iris-lens distance were two independent predictors of log(s)(P=0.003and P=0.049, respectively).CONCLUSION:Straylight seems to reduce in short-term after ICL surgery. Although there are some correlations between several anterior segment anatomic parameters with straylight, the overall correlation may be eliminated by other potential complex interactions of factors. The relative position between cornea, pIOL and crystalline lens as well as the refractive power of pIOL posterior surfaces are the factors contributing to affect starylight. |
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