Effects of cycloplegia on crystalline lens morphology and location in acute acquired concomitant esotropia.

PURPOSE: The study aims to compare morphology and location of crystalline lens between acute acquired concomitant esotropia (AACE) patients and control subjects, both before and after cycloplegia. METHODS: This is a prospective and observational clinical study. Morphological and locational parameters of the crystalline lens in 53 AACE patients and 32 control subjects were assessed before and after cycloplegia using CASIA2 system, which represents the latest swept-source anterior segment optical coherence tomography. Cycloplegic refraction was recorded by administering 1% atropine in patients younger than 12 years and 1% cyclopentolate in those > 12 years old. Morphological parameters included anterior radius of curvature (ARC), posterior radius of curvature (PRC), lens thickness (LTH), and equivalent diameter of lens (LED). Locational parameters comprised lens decentration (LD) and lens tilt (LT). Comparison of these parameters before and after cycloplegia were conducted between AACE and controls. Additionally, the study analyzed and compared the changes in these parameter post-cycloplegia. RESULTS: Our findings suggest no significant difference in morphological parameters including ARC, PRC, LTH and LED between AACE patients and controls before or after cycloplegia. However, 2D-modeling data in the 0° meridian revealed that variation post-cycloplegia of LD (lens shift) in right eyes was different in AACE patients, measuring - 0.03(0.08) [median(interquartile range)] which was significantly distinct from the control group, exhibiting a measurement of 0.01(0.06) (z = - 2.373, p = 0.018). In left eyes, a similar trend was observed with lens shift in the 0° meridian being 0.02(0.06) in AACE, significantly differing from control group's measurement of - 0.02(0.08) (z = - 2.809, p = 0.005). Further, correlation analysis revealed that larger temporal shift of lens was associated with greater changes in ARC (r = 0.294, p = 0.006) and LTH (r = - 0.230, p = 0.031). CONCLUSIONS: The morphological features of the crystalline lens were similar in AACE patients and controls; however, the change of lens location by cycloplegia was observed only in AACE patients, suggesting an association with excessive accommodation.

Analysis of the relationship between lens morphology and aberrations in patients with myopia: a cross-sectional study.

PURPOSE: To investigate the relationship between lens morphology and aberrations in patients with myopia. METHODS: This cross-sectional study included 155 patients with myopia in their right eyes. Spherical power and cylindrical power were achieved by cycloplegic autorefraction. The eyes were divided into three groups for analysis based on their spherical equivalent (SE) values. The 4 mm and 6 mm ocular and internal aberrations were measured using the OPD-scan III. Lens parameters were measured using CASIA2, including lens thickness (LT), radius of anterior/posterior lens surface curvature (RAL/RPL), lens decentration (DEC), and lens tilt (TILT). The differences of lenticular parameters and aberration parameters among the three groups analyzed with ANOVA or Kruskal Wallis test. Pearson correlation or Spearman correlation analysis was performed to evaluate the relationships between the lens parameters and aberrations. A p value < 0.05 indicated statistical significance. RESULTS: The difference in LT, RAL, DEC and TITL among the three groups was statistically significant (p < 0.05). And there were differences among differences in internal high-order aberrations, spherical aberration, and coma aberration(p < 0.05).Spherical power was positively correlated with LT and TITL (p < 0.05) and negatively correlated with DEC, RAL, and RPL (p < 0.05). Cylindrical power was positively correlated with LT (p < 0.05) and negatively correlated DEC (p < 0.05); The lenticular parameters (LT, RAL, DEC, and TILT) were mainly correlated with the ocular and internal spherical aberration. LT and DEC were correlated with ocular and internal higher-order aberrations and coma aberration. CONCLUSION: DEC and LT were the main factors affecting aberrations in patients with myopia.

Characterization of Unique Lens Morphology in a Cohort of Children with Familial Exudative Vitreoretinopathy.

Purpose: To characterize the lens morphology and to measure the clinical features of familial exudative vitreoretinopathy (FEVR) in children. Methods: Unique lens changes were observed in a cohort of children with FEVR from March 2015 to November 2017 using slit lamp examination and all the patients underwent cycloplegic refraction, ultrasound A and B, keratometry and fundus fluorescein angiography. Results: Twelve eyes of eight children with FEVR had unique lens changes. The contraction of the posterior capsule caused unique lens changes resulting in myopia in nine eyes of six children and astigmatism in eight eyes of five children. Retinal lesions in the affected eyes were all stage 1 to 2. Six eyes of three patients underwent lensectomy and intraocular lens implantation due to high anisometropia which could not be corrected by conventional optical correction. During lensectomy, the opacification in the posterior capsule was found to be due to the fibrous membrane that protruded into the anterior vitreous and not due to lens opacification. Three patients had bilateral lensectomy, in two of whom significant macular involvement was observed in one eye and in one of whom significant macular involvement was observed in both eyes. After surgery visual acuity (VA) improved obviously in two eyes without significant macular involvement and did not improve in the four eyes which had significant macular involvement. Among the five patients who did not have lensectomy, one patient was lost to follow-up and one patient had VA improved in both eyes without significant macular involvement. The other three patients did not have much change in VA. Conclusions: Clinicians should be aware that when a high myopia or astigmatism does not match the corneal curvature and the length of the eye, one should check carefully the changes of lens and fundus after dilating the pupil, to avoid misdiagnosis and missed diagnosis.

Non-invasive measurements of the dynamic changes in the ciliary muscle, crystalline lens morphology, and anterior chamber during accommodation with a high-resolution OCT.

PURPOSE: The purpose of the study was to assess non-invasively the changes in the anterior chamber eye, crystalline lens morphology, and ciliary muscle during accommodation by means of an anterior chamber optical coherence tomographer (OCT), and correlate them with vergence. METHODS: Twenty-five eyes of twenty-five healthy subjects, whose mean age was 29.9±7.1 years, were included and measured with an anterior chamber OCT. The central corneal thickness (CCT), anterior chamber depth (ACD), anterior crystalline lens radius of curvature (ALRC), crystalline lens thickness (CLT), and ciliary muscle area (CMA) were measured for each participant at 0, -1, -2, and -3 D of target vergence. A linear model was used to assess the correlation of each eye parameter with the vergence demand. RESULTS: The mean CCT showed no change for all the accommodative stimuli. The mean ACD and ALRC decreased with the vergence, about 4.5 and 30 % at -3 D, respectively. On the contrary, the CLT and CMA showed an opposite tendency, where the mean CLT was increased by 4.0 % and the mean CMA was done by 26% at -3 D. Statistical significant differences (p < 0.001) were obtained among all vergences for each eye metric, except for the CCT (p = 0.76). CONCLUSION: The ACD and ALRC decreased about 2 and 10 % per dioptre of accommodation, respectively; whereas the CLT and CMA increased about 2 and 9 %, respectively. These results add knowledge regarding the understanding of accommodation and give new perspectives for biomechanics and biometry.