Visual Outcomes Early after Implantable Collamer Lens V4c Implantation in Different Preoperative Spectacle Correction: Full Correction vs. Under Correction.

PURPOSE: To investigate visual outcomes early after implantable collamer lens (ICL) V4c implantation between patients with fully corrected and under-corrected spectacles preoperatively. METHODS: Patients who implanted ICL V4c were divided into the full correction (46 eyes/23 patients) and under-correction groups (48 eyes/24 patients) based on preoperative differences between the spherical diopter of the spectacles and the actual spherical diopter. Refractive outcomes, scotopic pupil size, higher-order aberrations, and subjective visual outcomes as assessed using a validated questionnaire were compared between the two groups 3 months postoperatively. Moreover, the relationships between the severity of haloes and postoperative ocular or ICL parameters were analyzed. RESULTS: At the 3-month follow-up, the efficacy indices in the full correction and under-correction groups were 0.99 ± 0.12 and 1.00 ± 0.10, respectively; the safety indices were 1.15 ± 0.16 and 1.15 ± 0.15, respectively. Total-eye spherical aberration (p < 0.0001) and internal spherical aberration (p = 0.0005) were significantly different pre- and post-operatively in the under-correction group, while no differences were found in the full correction group. Total-eye spherical aberration (p = 0.002) and the severity of haloes (p = 0.03) were postoperatively different between the two groups. The severity of haloes was associated with postoperative spherical aberration (total-eye spherical aberration: r = -0.32, p = 0.002; internal spherical aberration: r = -0.24, p = 0.02). CONCLUSION: Good efficacy, safety, predictability, and stability were obtained early after surgery regardless of preoperative spectacle correction. Patients in the under-correction group possessed a shift to negative spherical aberration and reported greater severity of haloes at the 3-month follow-up. Haloes were the most common visual symptoms after ICL V4c implantation and the severity of them was correlated with postoperative spherical aberration.

Short-term Evaluation of Visual Quality, Amplitude of Accommodation, and Stereoacuity Between Patients With Moderate-to-High Myopia Who Underwent ICLV4c Implantation and SMILE.

PURPOSE: To compare the visual quality, accommodation, and stereoacuity between patients with a myopia magnitude of -3.00 to -8.50 diopters (D) who underwent ICLV4c (STAAR Surgical) implantation and small incision lenticule extraction (SMILE). METHODS: The visual quality parameters, amplitude of accommodation (AMP), and stereoacuity were compared between and within the ICLV4c and SMILE groups (40 eyes/group) with a mean spherical equivalent (SE) of -6.14 D. Differences in these parameters before and after surgery were analyzed using SPSS 22.0 software (SPSS, Inc). RESULTS: Modulation transfer function (MTF) cut-off increased significantly by 3.24 cycles/degree (t = -2.111, P = .041) and AMP decreased significantly by 1.66 D (t = 7.519, P < .001) from baseline to 3 months after surgery in the ICLV4c group. However, the MTF cut-off was significantly lower (t = 2.123, P = .037) and the AMP was significantly better (t = -3.605, P = .001) in the SMILE group than in the ICLV4c group at 3 months postoperatively. Other parameters such as Objective Scatter Index, Strehl ratio, and Optical Quality Analysis System (Visiometrics) under different contrast values did not show significant changes (P > .05). Stereoacuity did not improve significantly, except in a patient with anisometropia (2.50 D) in the ICLV4c group. CONCLUSIONS: The ICLV4c implantation yielded a better visual quality but worse AMP than did SMILE in patients with a myopia magnitude of -3.00 to -8.50 D in the short term. [J Refract Surg. 2022;38(10):632-640.].

Comparison of anterior chamber angle changes following phakic intraocular lens with and without a central hole implantation for moderate to high myopic eyes.

The aim of this study was to compare the anterior chamber angle changes after implantation of phakic intraocular lens with and without a central hole for moderate to high myopic eyes in Chinese people.This study enrolled 106 eyes of 54 people with intraocular lens V4 implantation and 105 eyes of 53 people with intraocular lens V4c implantation. Postoperative vault, intraocular pressure, and anterior chamber angle changes were assessed using noncontract tonometer and ultrasound biomicroscope, respectively, at 1, 3, 6, and 12months after the surgery.There were no significant differences (all P > .05) between the 2 groups in the depth of the central vault, intraocular pressure, or the width of anterior chamber angle at any time point post-surgery. The anterior chamber angle width in degree had a baseline of 54.40 ±â€Š10.51 in V4c group, and decreased to 27.80 ±â€Š5.62, 26.95 ±â€Š5.56, 27.32 ±â€Š5.66, 27.04 ±â€Š5.47 at 1, 3, 6, and 12 months post-surgery, respectively. Mean preoperative value of 50.62 ±â€Š11.77 decreased to 27.28 ±â€Š6.53, 26.82 ±â€Š6.03, 26.61 ±â€Š5.80, 26.83 ±â€Š5.76 at 1, 3, 6, 12 months, respectively, in V4 group. It had sufficient evidence (P < .001) that anterior chamber angle will narrow done after surgery, but there were no statistically significant differences within groups at any time point after surgery.The anterior chamber angle changes of the V4c group was essentially equivalent to that of conventional V4 group, although implantation of both models will lead to the decrease in anterior chamber angle width.

Long-term ultrasound biomicroscopy observation of position changes of a copolymer posterior chamber phakic intraocular lens.

PURPOSE: To evaluate longitudinal changes in Implantable Collamer Lens phakic intraocular lens (pIOL) position after implantation. SETTING: Department of Ophthalmology, Zhejiang University, Hangzhou, China. DESIGN: Retrospective case series. METHODS: Myopic eyes that had pIOL implantation with a follow-up of at least 24 months were evaluated. Ultrasound biomicroscopy examinations were performed at each visit. RESULTS: The study enrolled 62 eyes (31 patients; 22 women, 9 men) ranging in age from 21 to 46 years. The manifest spherical equivalent ranged from -8.25 to -18.75 diopters. A significant increase (mean 36 µm±50 [SD]) in the endothelium-anterior pIOL distance occurred between 1 month and 3 months (P=.000); afterward, the distance decreased slowly (P>.05). The largest decrease (mean 47±17 µm) in central vault occurred between 1 month and 3 months (P=.009). The largest decrease (mean 21±14 µm) in peripheral vault occurred between 1 month and 3 months (P=.000). CONCLUSIONS: A significant increase in the endothelium-anterior pIOL distance occurred from 1 month to 3 months postoperatively, after which a slight decrease occurred over time. Central vault and peripheral vault had a tendency to decrease over time. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

[Selection of the posterior chamber phakic intraocular lens length].

OBJECTIVE: To evaluate the efficacy, safety and clinical value of calculating the posterior chamber phakic intraocular lens (ICL) length according to the corneal horizontal diameter. METHODS: This was a retrospective study. A Staar Visian implantable contact lens (ICL) was implanted in 32 patients (64 eyes) with high myopia in the Department of Ophthalmology, the First Affiliated Hospital, College of Medicine, Zhejiang University between November 15, 2005 and January 15, 2011. The lens length was calculated according to the corneal horizontal diameter measured by Orbscan II. Patients were followed up postoperatively at 1 day, 1 week, 1, 3, 6 and 12 months and every 6 months thereafter. The evaluations included visual acuity, manifest refraction, applanation tonometry, endothelial cell count, slit-lamp microscopy to detect cataract, and UBM to assess the degree of ICL tilt and distances between the corneal endothelium, the ICL, and the crystalline lens. All of the preoperative and 12-month follow-up observations were analyzed using SPSS 16.0 software. RESULTS: No anterior subcapsular cataracts were found in any of the eyes after surgery. Pigmentary dispersion was observed on the anterior and posterior surface of the ICL, but the difference was not statistically significant (χ(2) = 2.24, P = 0.13). The intraocular pressure changed from (15.67 ± 3.23) mm Hg (1 mm Hg = 0.133 kPa) to (15.78 ± 3.23) mm Hg, but the difference was not significant (t = 0.24, P = 0.38). The corneal endothelium-lens (central section) distance measured by UBM postoperatively was (2.97 ± 0.25) mm and the corneal endothelium-ICL (central section) distance was (2.24 ± 0.27) mm; the difference between them was statistically significant (t = 15.77, P < 0.01). The degree of ICL tilt measured by UBM was 1.20° ± 1.05 °. The percentage of eyes with a trabecular-iris angle (TIA) greater than 30°, between 21° and 30°, between 11°and 20°, and smaller than 10° were 29.1%, 50.0%, 11.6%, and 9.3%, respectively. The angle opening distance at 500 micron (AOD500) measured by UBM postoperatively was (0.32 ± 0.15) mm. The contact distance between the iris and the ICL measured by UBM postoperatively was (0.85 ± 0.46) mm and the ICL-lens central distance was (0.47 ± 0.25) mm. The Pearson's correlation coefficients between the ICL-lens central distance and the corneal horizontal diameter, sulcus diameter, anterior chamber depth(ACD) and ICL length were 0.11, 0.16, 0.04 and 0.19, respectively; none were statistically significant. The ICL-lens peripheral distance measured by UBM postoperatively was (0.25 ± 0.20) mm. CONCLUSION: Selecting the length of the ICL according to the corneal horizontal diameter is appropriate, and assures the safety, effectiveness and predictability of ICL implantation.

[Mid-long term follow-up results in correction of extreme myopia by posterior chamber phakic intraocular lens].

OBJECTIVE: To evaluate the mid-long term stability and safety of posterior chamber phakic intraocular lens (ICL) implantation for the correction of extreme myopia. METHODS: This retrospective study included 993 eyes of 498 patients received ICL implantation from June 1996 to December 2008. Multivariate analysis and variance analysis were used to evaluate the stability of the results and to identify risk factors of the complications. RESULTS: Successful implantation was achieved in all patients. Spherical equivalent (SE) was (16.23 ± 4.12, mean ± SD) D before the operation and (-0.92 ± 1.22) D at the last examination. Intraocular pressure was (13.58 ± 2.93) mm Hg (1 mm Hg = 0.133 kPa) preoperatively which was (13.90 ± 3.01) mm Hg at the last examination. There was no statistical significance in follow-up (t = 0.44 ∼ 1.30, P > 0.05). Endothelial cell density was (2858.21 ± 395.13)/mm(2) before the operation and (2567.19 ± 423.45)/mm(2) at last examination. Pupillary block glaucoma occurred in 2 eyes (0.2%) at two hours and 1 eye (0.1%) at one month after the operation. Three eyes developed anterior cataracts between 6 months to 1 year after ICL implantation and another 2 eyes subcapsular opacification at semi-peripheral regions occurred 4 years after the operation, and was not related with age, SE and vaults (F = 2.42, 1.98, 0.81, P > 0.05). Macular puckers were found in 5 eyes (0.5%) 1 year postoperatively, including 2 eyes developed choroidal neovascularization and received PDT, best corrected visual acuity lost more than 2 lines. Retinal detachment occurred in 2 eyes at 1.5 years after the operation. Acute iritis happened in 1 eye (0.1%) and chronic iritis in 1 eye (0.1%) which combined with slight pupil distortion and elevation of intraocular pressure. Iris stroma atrophy and pupil distortion were found in 2 eyes (0.2%). CONCLUSION: Correction of high myopia by ICL implantation is a safe procedure and the results are stable.

[Posterior chamber phakic intraocular lens for correction of extreme myopia].

OBJECTIVE: To evaluate the efficacy, safety and stability of posterior chamber phakic intraocular lens implantation for the correction of extreme myopia. METHODS: This study included 216 eyes of 113 patients with a mean age of 30 years (18 approximately 49) from January 1997 to December 2005. An implantable contact lens (ICL V2 and V4, Staar Surgical Inc.) was inserted. Patients were examined preoperatively and followed at 1 day, 1 week, 1, 3, 6, 12, 24, and 36 months postoperatively. The examination content included the uncorrected visual acuity, best corrected visual acuity (BCVA), slitlamp examination, refraction, intraocular pressure, endothelial cell morphometry, etc. Spherical equivalent was (17.78 +/- 3.88) diopters before the operation. Surgical implantation was performed through a 3.2 mm clear corneal sutureless incision using paraocular anesthesia. The mean follow-up period was 18.2 months (ranged 6 to 24 months) for refractive data and 24.3 months (ranged 6 to 36 months) for the complications. RESULTS: Successful implantation was achieved in all patients. Postoperatively, all eyes had a significant increase in uncorrected visual acuity. The mean spherical equivalent refraction at the last examination was (-1.00 +/- 1.40), within +/- 1.00 D of the targeted refraction in 191 eyes (88.4%) and within +/- 0.50 D in 165 eyes (76.4%). In eyes in which the preoperative myopia was less than 20.00 D (n = 151), the achieved refraction was within +/- 1.00 D of the intended refraction in 145 eyes (96.0%) and within +/- 0.50 D in 128 eyes (84.8%). The refraction remained stable with a statistically insignificant change (P > 0.05) at each interval during the follow-up. The best corrected visual acuity (BCVA) improved by 1 or more lines in 168 eyes (77.8%) at 1 year after the operation. Four eyes (1.85%) lost 1 line of BCVA. Pupillary block glaucoma requiring surgical intervention occurred in 4 eyes (1.85%). Three eyes (1.39%) developed cataract 1 year after ICL (V2) implantation, all ICLs in these eyes were removed, and the refractive errors were corrected by lensectomy and implantation of low-power posterior chamber IOLs. BCVA was mentioned in all of these eyes. CONCLUSION: Posterior chamber phakic intraocular lens implantation appears to be an effective, safe and reliable method for the correction of extreme myopia.