Changes in anterior chamber volume after implantation of posterior chamber phakic intraocular lens in high myopia

Abstract

BackgroundThe present study aimed to assess changes in, and the factors that influence, anterior chamber volume (ACV) after implantable contact lens (ICL) implantation in high myopia eyes using a Pentacam.MethodsThe study sampled 26 high myopia patients (45 eyes) who were treated with ICL implantation. These patients were followed for an average of 4.28 months postoperatively. ACV was measured with a Pentacam preoperatively and at 3 months postoperatively. The data were analyzed by paired samples Wilcoxon signed-rank test. Generalized estimating equation (GEE) model adjusting within-patient intereye correlations in addition to Pearson’s and Spearman’s correlation tests were performed to determine associations.ResultsThe mean ACV was 198.33 ± 33.08 mm3 before surgery and 118.65 ± 17.70 mm3 after surgery. A significant decrease of 79.68 mm3 (40.18%) (Z = 5.841, P < 0.001) was detected. Positive correlations were found between ACV changes and ICL central vault (r = 0.528, P < 0.001) and preoperative anterior chamber depth (ACD) (r = 0.665, P < 0.001). There were positive correlations between postoperative ACV and postoperative anterior chamber angle (ACA) at 3:00 o’clock (r = 0.448, P = 0.002) and at 9:00 o’clock (r = 0.405, P = 0.006). GEE regression model showed that postoperative ACV significantly positively correlated with preoperative ACV (P = 0.002), ACD (P = 0.002) and horizontal ACA (P = 0.005) and negatively correlated with ICL central vault (P < 0.001).ConclusionComplementary to vault and ACD, ACV is a sensitive parameter with certain value of preoperative assessment and postoperative monitoring in ICL implantation.

Characteristics and factors associated with the position of the haptic after ICL V4C implantation

“…17 It has been proved to be an important factor related to the clinical vault after surgery; in previous studies, Zhu et al reported a nearly 40% of decreased ACV after surgery. 6,18 They also found a significant positive correlation between the preoperative and postoperative ACV. Consistent with their reports, Takagi et al selected the preoperative ACV as an important variable to establish the prediction formula of postoperative ACV.…”

Prediction of anterior chamber volume after implantation of posterior chamber phakic intraocular lens

“…A previous study used Scheimpflug-based tomography (Pentacam, Oculus, Arlington, WA) for the prediction equation to calculate the postoperative ACV [11]. The authors reported that the postoperative ACV is correlated with the postoperative vault, preoperative ACV, ACD, and horizontal ACA and can also be predicted by these parameters.…”

“…A previous report showed that intraocular pressure (IOP) was elevated by angle closure after ICL implantation [10]. ACV measured by anterior segment optical coherence tomography (AS-OCT) was useful for observing the change of anterior segment and angle structure after ICL implantation [11]. Based on these studies, we presumed that ACV would be useful for predicting the anterior chamber angle after ICL implantation.…”

“…Using Scheimpflug-based corneal tomography, a previous study showed that ACV significantly decreased after ICL implantation and that changes in ACV were correlated with preoperative ACV, preoperative ACD, preoperative horizontal anterior chamber area (ACA), and ICL vault [11]. In addition, the same study reported that postoperative ACV was predicted by four parameters, including preoperative ACV, preoperative horizontal ACA, preoperative ACD, and postoperative vault.…”

An anterior segment optical coherence tomography study of the anterior chamber angle after implantable collamer lens-V4c implantation in Asian Indian Eyes

“…evaluated the AC volume (ACV) (Pentacam imaging) after ICL implantation in 45 eyes of 26 patients with high myopia preoperatively and postoperatively over a mean follow-up period of 4.28 months. [ 16 ] The mean ACV was found to decrease significantly (a decrease of 40%) from 198.33 ± 33.08 mm 3 before surgery to 118.65 ± 17.70 mm 3 after surgery. They found a positive correlation between postoperative ACV and ACA and concluded the ACV to be a sensitive parameter that is complementary to vault and ACD in preoperative assessment and postoperative monitoring of ICL patients.…”