Anterior Lens Research Articles

Reposition of dislocated piggyback intraocular lens in a patient with induced keratectasia after radial keratotomy

Aim – to substantiate low-traumatic sutureless surgery for piggyback intraocular lens (IOL) reposition as a method of choice in a patient after previous keratorefractive surgery and cataract phacoemulsification.
 The article provides the examination and surgical treatment data of one patient with piggyback intraocular lens dislocation after previous radial keratotomy and keratectasia.
 The presented clinical case shows that proper consideration of eye anatomical features allows for effective low-traumatic sutureless piggyback IOL reposition in patients who have previously undergone radial keratotomy, and may lead to sustainable high visual and functional results.

Expression Profiling of ADAMTS (L) Superfamily of Genes in Various Human Eye Tissues.

A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) is a superfamily of extracellular proteinases found in both mammals and invertebrates. Although there is some evidence about the role of ADAMTSs in ocular diseases such as glaucoma and ectopia lentis, but there is little information about the expression patterns of ADAMTS-1-20 and ADAMTS-like (ADAMTSL-1-6 and PAPLN) genes in human ocular tissues. This study aimed to evaluate the expression profiling of ADAMTS(L) superfamily of genes in different ocular tissues based on age. In 2019, nine human donated eye globes were provided from the Central Eye Bank of Iran, and were divided into three different groups based on age (under 3 yr old, between 20 to 50 and upper 50 yr old). To assess expression patterns of ADAMTS(L) genes in different ocular tissues including trabecular meshwork, lens, retinal pigment epithelium, macula, and optic nerve in the three age groups, total RNA was extracted from the tissues and reverse transcription polymerase chain reaction followed by Real-time PCR was performed. We demonstrated not only each member of ADAMTS(L) superfamily shows different expression pattern between the five investigated ocular tissues, but also some members have differential expressions among the investigated age groups in same tissues. Differential expression of ADAMTS(L) genes in ocular tissues from different age groups could explain some functional aspects of the tissues and also may be used as prognostic and diagnostic biomarkers for ocular diseases and pathologies. Further studies are required to explore their functional roles associated with ocular pathologies.

Variations in Lens Thickness Affecting the Anterior Chamber Length and Their Potential Measurement Using a Biometer

Biometry is a critical aspect of ophthalmology, since it facilitates the measurement of several ocular parameters and aids in the diagnosis of conditions like glaucoma. The advent of the IOLMaster in 1999 marked a pivotal moment in biometry by introducing non-contact and highly precise measurements that revolutionized the field. Low-coherence optical reflectometry devices such as Lenstar LS900 and Aladdin have further advanced biometry, due to the exceptional accuracy they offer. Axial length, a fundamental measurement in biometry, directly correlates with conditions like myopia and glaucoma. The accurate measurement of axial length is crucial for diagnosis and treatment planning. Biometry also guides intraocular lens power calculation during cataract surgery, relying on factors like axial length, anterior chamber depth, lens thickness, and effective lens position (ELP). Ensuring precision in these measurements is essential for optimal surgical outcomes. While several studies have explored biometric parameters, dynamic changes in crystalline lens thickness during rest or accommodation have received little attention. These changes may have a significant effect on the measurement of the anterior chamber length, and consequently impact the overall biometric assessment. This study delves into dynamic biometry, particularly in the context of age-related presbyopia, and aims to assess the feasibility of incorporating into the biometric process a specialized device capable of accurately considering crystalline lens changes during different states like rest and accommodation. This exploration seeks to enhance the understanding of ocular dynamics and contribute to improving the precision of diagnostic and surgical techniques. It underscores the importance of staying at the forefront of biometric research, especially in the context of emerging technologies and their potential to transform ophthalmology.

Effect of sutureless scleral fixed intraocular lens implantation on aphakic eyes: a system review and meta-analysis

BackgroundSutureless scleral fixed intraocular lens implantation (SF-IOL) has become one of the mainstream schemes in clinical treatment of aphakic eyes because of its advantages, such as avoiding dislocation of intraocular lens or subluxation caused by suture degradation or fracture and significant improvement of postoperative visual acuity. However, a consensus on the relative effectiveness and safety of this operation and other methods is still lacking. This study aimed to compare the efficacy and safety of sutureless SF-IOL with other methods. Aphakia means that the lens leaves the normal position and loses its original function, including absence or complete dislocation and subluxation of the lens which could cause anisometropic amblyopia, strabismus, and loss of binocular function in children and adolescents. For adults, the loss of the lens could lead to high hyperopia and affect vision. Above all this disease can seriously affect the quality of life of patients.MethodsLiterature about sutureless SF-IOL in PubMed, Cochrane Library, Embase, Web of Science, China National Knowledge Infrastructure, China Technical Journal VIP database, and Wanfang database published from 2000 to 2022 was reviewed. The weighted average difference was calculated by RevMan5.3 software for analysis. Two researchers independently selected the study and used the Cochrane collaboration tool to assess the risk of errors. Cochrane bias risk tool was used to evaluate the quality of evidence. This study is registered on PROSPERO (CRD42022363282).ResultsThe postoperative IOL-related astigmatism of sutureless SF-IOL was lower than that of suture SF-IOL, and there was statistical difference when we compared the absolute postoperative spherical equivalent after sutureless SF-IOL and suture SF-IOL. Indicating that the degree of refractive error after sutureless SF-IOL was lower. Meanwhile, the operation time of sutureless SF-IOL was shorter than that of suture SF-IOL. The subgroup analysis showed that the absolute postoperative spherical equivalent and astigmatism values in Yamane technique were lower than those in suture SF-IOL.ConclusionSutureless SF-IOL has the advantages of stable refraction, short operation time, and less postoperative complications. However, high-quality literature to compare these technologies is lacking. Some long-term follow-up longitudinal prospective studies are needed to confirm the findings.

Influence of Ocular Biometry Parameters on the Predictive Accuracy of IOL Power Formulas in Patients with High Myopia.

The aim of this study was to investigate the influence of ocular biometry parameters on the predictive accuracy of 10 intraocular lens (IOL) power formulas in patients with high myopia (HM). We analyzed 202 eyes of 202 patients. The ocular biometry was determined preoperatively using an IOLMaster700. The associations between the biometry parameters and the prediction error (PE) 1month postoperatively were assessed. HM was defined as an axial length exceeding 26.50mm. In patients with HM (n = 108), the K6, Emmetropia Verifying Optical (EVO), Olsen, and Barrett UniversalII (BUII) formulas had the lowest absolute PEs among the 10 formulas. The ocular biometry parameters were not associated with the PE of K6, EVO, Olsen, or BUII. A longer axial length in HM eyes was associated with myopic outcomes by Kane, Hoffer QST, and VRF and hyperopic outcomes by Holladay2 and T2. Steeper keratometry, a deeper anterior chamber, and a thicker lens were associated with a hyperopic shift in HM eyes when using VRF, Kane, and Hoffer QST, respectively. In patients without HM (n = 94), there was no difference between the formulas in absolute PE. The significant associations between the biometry parameters and PE in patients with HM were not present in patients without HM. K6, EVO, Olsen, and BUII displayed high accuracy in HM eyes and were not influenced by preoperative biometry parameters. For the remaining formulas, the preoperative keratometry, anterior chamber depth, lens thickness, and axial length were possible error sources underlying an inaccurate IOL power prediction in patients with HM.

The Outbreak of Acute Primary Angle-Closure Cases During the COVID-19 Omicron Variant Pandemic at a Tertiary Eye Center in Shanghai.

This study aimed to investigate the outbreak of acute primary angle-closure (APAC) during the COVID-19 Omicron variant pandemic in Shanghai. This single-center retrospective observational study included all newly diagnosed patients with APAC in Eye, Ear, Nose, and Throat Hospital of Fudan University from December 15, 2022, to January 14, 2023 (pandemic group) during the COVID-19 pandemic of Omicron Variant, and from November 15, 2021, to February 14, 2022 (control group) when the infection rate of COVID-19 is very low in Shanghai. Demographic features, intraocular pressure, axial length, anterior chamber depth, lens thickness and pupil diameter were compared between the two groups. A total of 223 patients (261 eyes) were included in the pandemic group and 75 patients (82 eyes) in the control group. The number of APAC patients and eyes in the pandemic group is 8.92-fold and 9.55-fold of the monthly average number in the control group. The onset dates of acute angle-closure were mainly between December 17 and December 31, 2022. In the pandemic group, 72.65% of patients with APAC had a recent COVID-19 infection. Among the COVID-19-positive patients, 72% suffered APAC attacks within 24h of the occurrence of COVID-19 symptoms and 92% within 3 days. The pandemic group showed a longer time from symptoms to treatment and larger pupil diameter than the control group (7.92 ± 6.14 vs 3.63 ± 2.93 days, p = 0.006; 4.53 ± 1.17 vs 3.78 ± 1.24 mm, p = 0.003, respectively). An outbreak of APAC attack was observed in our eye center during the COVID-19 Omicron variant pandemic in Shanghai. There may be a correlation between the onset of APAC and new COVID-19 Omicron variant infection, but the exact reason needs to be investigated further.

Evaluation of functional vision and eye-related quality of life in children with congenital ectopia lentis: a prospective cross-sectional study

ObjectivesThis study aims to evaluate the effect of congenital ectopia lentis (CEL) on functional vision and eye-related quality of life (ER-QOL) in children and their families using the Paediatric Eye...

The Complications of Cataract Surgery in Patients with Pseudoexfoliation

Abstract The senile cataract represents the blurring of the crystalline lens after the age of 65. It occurs due to metabolic changes in the crystalline lens which occur over the years. The only effective way to treat cataract is the surgical one. Pseudoexfoliation is an age related systemic disorder. PEX represents the accumulation fibrillar material in the extracellular matrix of the tissue. The most known ocular manifestation of the PEX are the collection at iris pupillary margin and anterior lens capsule. This accumulation is associated with many intraoperative and postoperative complications in patients scheduled for cataract surgery. The aim of the study was to investigate the prevalence of the surgical complications during phacoemulsfication in patients with PEX. The study included 91 patients scheduled for cataract surgery divided into two groups (PEX group 46, control group 45 patients). Poor intraoperative midryasis, zonular dehiscence, postoperative corneal edema, anterior chamber inflammation, elevated intraocular pressure and tear film instability had particularly higher rate of occurring in PEX group comparing to the control group (p<0.001). The highest mean value of intraocular pressure was observed in PEX group on the first postoperative day 25.6 ± 1.1 mmHg, while the best corrected visual acuity was measured in control group 0.71 ± 1.2 one month after phacoemulsification. Cataract surgery in patients with PEX carries great risk, but with adequate preoperative planning, the awareness of the potential complications, can provide safe and routine phacoemulification in these patients.

Age-related changes in geometry and transparency of human crystalline lens revealed by optical signal discontinuity zones in swept-source OCT images

BackgroundThe shape and microstructure of the human crystalline lens alter with ageing, and this has an effect on the optical properties of the eye. The aim of this study was to characterise the age-related differences in the morphology and transparency of the eye lenses of healthy subjects through the optical signal discontinuity (OSD) zones in optical coherence tomography (OCT) images. We also investigated the association of those changes with the optical quality of the eye and visual function.MethodsOCT images of the anterior segment of 49 eyes of subjects (9–78 years) were acquired, and the OSD zones (nucleus, C1–C4 cortical zones) were identified. Central thickness, curvature and optical density were measured. The eye’s optical quality was evaluated by the objective scatter index (OSI). Contrast sensitivity and visual acuity tests were performed. The correlation between extracted parameters and age was assessed.ResultsThe increase in lens thickness with age was dominated by the thickening of the cortical zone C3 (0.0146 mm/year). The curvature radii of the anterior lens surface and both anterior and posterior nucleo-cortical interfaces decreased with age (− 0.053 mm/year, − 0.013 mm/year and − 0.006 mm/year, respectively), and no change was observed for the posterior lens radius. OCT-based densitometry revealed significant correlations with age for all zones except for C1β, and the highest increase in density was in the C2–C4 zones (R = 0.45, 0.74, 0.56, respectively, P < 0.001). Increase in OSI was associated with the degradation of visual function.ConclusionsOCT enables the identification of OSD zones of the crystalline lens. The most significant age-related changes occur in the C3 zone as it thickens with age at a faster rate and becomes more opaque than other OSD zones. The changes are associated with optical quality deterioration and reduction of visual performance. These findings contribute to a better understanding of the structure–function relationship of the ageing lens and offer insights into both pathological and aging alterations.

Modeling Cataract Surgery in Mice.

Cataract surgery (CS) is an effective treatment for cataracts, a major cause of visual disability worldwide. However, CS leads to ocular inflammation, and in the long term, it can result in posterior capsular opacification (PCO) and/or lens dislocation driven by the post-surgical overgrowth of lens epithelial cells (LECs) and their conversion to myofibroblasts and/or aberrant fiber cells. However, the molecular mechanisms by which CS results in inflammation and PCO are still obscure because most in vitro models do not recapitulate the wound healing response of LECs seen in vivo, while traditional animal models of cataract surgery, such as rabbits, do not allow the genetic manipulation of gene expression to test mechanisms. Recently, our laboratory and others have successfully used genetically modified mice to study the molecular mechanisms that drive the induction of proinflammatory signaling and LEC epithelial to mesenchymal transition, leading to new insight into PCO pathogenesis. Here, we report the established protocol for modeling cataract surgery in mice, which allows for robust transcriptional profiling of the response of LECs to lens fiber cell removal via RNAseq, the evaluation of protein expression by semi-quantitative immunofluorescence, and the use of modern mouse genetics tools to test the function of genes that are hypothesized to participate in the pathogenesis of acute sequelae like inflammation as well as the later conversion of LECs to myofibroblasts and/or aberrant lens fiber cells.

Familial Congenital Aniridia with Subluxated Lens and Glaucoma

Introduction: Congenital aniridia is a bilateral iris aplasia or hypoplasia associated with other ocular disorders. The purpose of this case report is to describe the clinical manifestation of congenital aniridia in two members of one family. Case Presentation: The first patient (mother) is a 43-year-old and the second patient (daughter) is a 12-year-old. Both patients complained of blurred vision since childhood. The visual acuity of the first patient was a positive light perception on the right eye (RE) and no light perception on the left eye (LE); the visual acuity of the second patient was 1/60 on the RE and 3/32 on the LE. Both patients had horizontal nystagmus and increased intraocular pressure (IOP) (N+1 palpation) in both eyes. Anterior segment abnormalities of both patients include aniridia with iris rudimentary and superiorly subluxated lens. The first patient also had LE corneal leukoma and RE cataract. The second patient also had right and left eye corneal conjunctivalization. Fundus examination showed no fundus reflex on the first patient and tigroid retina with foveal hypoplasia on the second patient. Eye ultrasounds of both patients showed vitreous opacity. Conclusions: Congenital aniridia primarily originates from a mutation in the paired box gene-6 (PAX6) and is associated with other ocular anomalies such as nystagmus, amblyopia, keratopathies, cataract, lens luxation, glaucoma, fovea, optic nerve hypoplasia. Patients in this case showed similar conditions between mother and daughter, however, the mother's condition was more advanced and more degenerated than the daughter's condition.

Towards the Identification and Characterization of Putative Adult Human Lens Epithelial Stem Cells.

The anterior lens epithelium has the ability to differentiate into lens fibres throughout its life. The present study aims to identify and functionally characterize the adult stem cells in the human lens epithelium. Whole mounts of lens epithelium from donor eyes (normal/cataract) were immunostained for SOX2, gap junction protein alpha 1 (GJA1), PAX6, α, β and γ-crystallins, followed by a confocal analysis. The functional property of adult stem cells was analysed by their sphere forming ability using cultured lens epithelial cells from different zones. Based on marker expression, the lens epithelium was divided into four zones: the central zone, characterized by a small population of PAX6+, GJA1-, β-crystallin- and γ-crystallin- cells; the germinative zone, characterized by PAX6+, GJA1+, β-crystallin- and γ-crystallin-; the transitional zone, characterized by PAX6+, GJA1+, β-crystallin+ and γ-crystallin-; and the equatorial zone, characterized by PAX6+/-, GJA1+, β-crystallin+, and γ-crystallin+ cells. The putative lens epithelial stem cells identified as SOX2+ and GJA1 membrane expression negative cells were located only in the central zone (1.89 ± 0.84%). Compared to the other zones, a significant percentage of spheres were identified in the central zone (1.68 ± 1.04%), consistent with the location of the putative adult lens epithelial stem cells. In the cataractous lens, an absence of SOX2 expression and a significant reduction in sphere forming ability (0.33 ± 0.11%) were observed in the central zone. The above findings confirmed the presence of putative stem cells in the central zone of the adult human lens epithelium and indicated their probable association with cataract development.

IOLcano Eruption: Eye on Fire With Rubeosis Iridis' Lava Flow

A 40-year-old male presented with visual impairment in the right eye (OD). He had undergone a pars plana vitrectomy for retinal detachment in the OD three years prior. Biomicroscopic examination revealed significant hyperemia, rubeosis iridis, anterior subluxation of the intraocular lens (IOL), and an organized hyphema located in the inferior third of the anterior chamber, characterized by the entrapment of iris tissue between the anterior synechia and the IOL.

Traction suture fixation technique using a capsular tension ring fragment for severe lens displacement during cataract surgery in dogs.

To describe the traction suture fixation technique for severely displaced lenses (≥180°) using a capsular tension ring (CTR) fragment during cataract surgery in dogs, and to retrospectively investigate its clinical outcomes. Eight dogs (nine eyes). The medical records of dogs with severe lens displacement (≥180°) due to cataracts that underwent traction suture fixation during cataract surgery using a CTR fragment at the Grand Animal Hospital (Hyogo, Japan) between November 2019 and September 2022 were retrospectively reviewed. The retrieved data included the signalment, type of CTR, and postoperative outcomes. A single CTR fragment was used to fix the capsular bag to the sclera in six eyes, and two CTR fragments were used at two sites in three eyes. The lengths of the CTR fragments used were 1 one-fifth fragment, 3 one-fourth fragments, and 8 one-third fragments. Postoperative complications included uveitis (nine eyes), glaucoma (one eye), posterior iris adhesion (one eye), corneal ulcer (one eye), and intracorneal stromal hemorrhage (one eye). Vision was maintained in all dogs during the follow-up period (2 months to 2 years and 8 months) without recurrent capsular bag displacement. This technique can correct and stabilize capsular bag displacement relatively easily through a small incision during cataract surgery in dogs with severe lens displacement. Intraocular lens implantation was also possible.

Direct generation of lower-order cylindrical vector vortex modes from an end-pumped Pr3+:LiYF4 laser

We report the direct generation of vector vortex laser modes at 640 nm from a compact, diode end-pumped continuous-wave Pr3+:LiYF4 (YLF) laser that utilizes an intracavity lens and diaphragm. On-axis displacement of the intracavity lens, combined with appropriate choice of the intracavity diaphragm, enables selective generation of a desired radial and azimuthal vector laser mode. Such compact, vector vortex laser sources based on Pr3+:YLF in the visible wavelength region are a significant enabling technology for a wide range of applications.

Initial screening for occult congenital ectopia lentis based on ocular biological parameters in preschool children

BackgroundThis study aimed to identify an initial screening tool for congenital ectopia lentis (CEL) by comparing ocular biological parameters in children with myopia.MethodsA retrospective case-control study was conducted at one tertiary referral centre, from October 2020 to June 2022. Axial length (AL), corneal curvature (CC), refractive astigmatism (RA), corneal astigmatism (CA), internal astigmatism (IA), the difference between the axis of RA and CA [AXIS(RA-CA)], white-to-white corneal diameter (WTW), and axial length-corneal radius ratio (AL/CR) were compared in 28 eyes of CEL patients, and 60 eyes of myopic patients matched for age and refraction. The spherical equivalent of each eye was < -3.00 D. Area under the curve (AUC) of the receiver operating characteristic curves were calculated.ResultsThe differences in RA, AL, mean keratometry (Kmed), maximum keratometry (Kmax), minimum keratometry (Kmin), CA, IA, AXIS(RA-CA), WTW, and AL/CR between the CEL and myopic groups were statistically significant (p < 0.05; p < 0.001; p < 0.001; p < 0.001; p < 0.001; p < 0.05; p < 0.001; p < 0.001; p < 0.001; p < 0.001, respectively). In logistic regression analysis RA, IA, AXIS(RA-CA), and AL/CR were significantly associated with CEL (p < 0.05). AUCs for RA, IA, AXIS(RA-CA), and AL/CR were 0.694, 0.853, 0.814, and 0.960, respectively. AUCs for AL/CR in SE< -6.00 D subgroup was 0.970, and 0.990 in -6.00 D ≤ SE < -3.00 D group. An AL/CR < 3.024 was the optimal cut-off point differentiating the CEL and control groups (sensitivity, 92.9%; specificity, 88.30%).ConclusionsA smaller AL/CR could identify CEL in children with myopia. An AL/CR cut-off value of 3.024 may be the most sensitive and specific parameter for the differential diagnosis of CEL in patients with mild to high myopia.

Characterisation of cataracts and other ophthalmic findings in various species of captive penguins.

The identification of ophthalmic diseases that affect vision and/or cause discomfort should be a priority in captive penguins to improve their overall health and quality of life. A routine ophthalmological examination was performed on 80 clinically normal penguins (160 eyes), and any lesions observed were recorded. Ocular lesions were frequent (56% of penguins), with cataracts being the most common (48.8% of penguins). Cortical cataracts (63% of eyes) and posterior subcapsular cataracts (27.4%) were the most commonly occurring. All maturation stages were found; incipient cataracts (52.1% of eyes with cataracts) were predominant, while Morgagnian cataracts (8.2%) were the least frequent. A correlation existed between lenticular changes and increasing age. Uveitis was present in 43.8% of eyes with cataracts, and ectropion uveae was the predominant clinical sign. Other ocular findings included blepharitis (3.8% of all eyes), corneal leukoma (5.6%) and posterior lens subluxation (7.5%). The small number of birds of some species prevented the comparison of ophthalmic findings between species. This study corroborates the high prevalence of ocular lesions in captive penguins. Cataracts were frequent and age related. Most cataracts were cortical, and the predominant maturation stage was incipient. Lens-induced uveitis was a common finding. Lowered intraocular pressure was related to cataract formation.

The Successful Replacement of Aortic Valve and Ascending Aorta in Patients with Type A Aortic Dissection in the Postpartum Period. The Analysis of Literature and Demonstration of Own Observations

Abstract. Aortic dissection is a rupture of the inner layer of the aorta with subsequent penetration of blood into the degeneratively altered middle layer with the formation of false lumen and true lumen. Pregnancy is one of the risk factors for the development of aortic dissection. The incidence of aortic dissection during pregnancy is only 0.0004% of cases.Aim of the study. To analyze national and foreign literature, as well as share own clinical observations in the diagnosis and treatment of patients with aortic dissection in the postpartum period.Material and methods. Two patients after successful childbirth, in the late postpartum period, were admitted with a diagnosis of aortic dissection type A according to Stanford.CT angiography confirmed the presence of Stanford type A aortic dissection. After additional examination, surgical treatment was performed to replace the aortic valve and ascending aorta under artificial circulation, with a satisfactory clinical result.Conclusion. The diagnosis of aortic dissection should be considered in all pregnant women with chest pain, as this condition often goes undiagnosed.The pregnancy period is one of the risk factors for the development of aortic dissection with a high mortality rate. The likelihood of developing aortic dissection in women at risk peaks in the third trimester and the first 12 weeks after delivery.The risk group should include women with confirmed syndromic and non-syndromic genetic diseases, bicuspid aortic valve, coarctation of the aorta, or at least one major criterion indicating the presence of aortopathy (ectopia lentis, aortic aneurysm, habitus, genetic testing).If Marfan syndrome is present, surgical intervention should be considered if the maximum aortic diameter is more than 4.5 cm before pregnancy. In women with Marfan syndrome and aortic dissection in the family history, as well as in the presence of more aggressive genetic diseases (Loeys-Dietz syndrome, Ehlers-Danlos syndrome), it is possible to consider preventive surgical treatment for an aortic diameter of 4.0 cm or more.The delivery in high-risk patients is recommended to be performed in a hospital that has a cardiac surgery service and an “aortic” team.

Interocular difference in crystalline lens morphology in children and adolescents with unilateral high myopia

PurposeTo investigate the between-eye differences of the crystalline lens in subjects with unilateral high myopia and assess its contribution to the interocular refractive error disparity. MethodsChildren and adolescents with unilateral high myopia, defined as cycloplegic spherical equivalent (SE) ≤ −5D in one eye and ≥ −3D in the other eye, were recruited. Ocular biometric parameters, including axial length (AL) and lens thickness (LT), were measured by IOLMaster 700. Other lens-related parameters, including anterior lens radius of curvature (ALR) and posterior lens radius of curvature (PLR), were measured by CASIA2 swept-source optical coherence tomography. Lens power (LP) was calculated using Bennett’s formula. Paired t-test was used to assess the between-eye difference in biometric parameters, and multiple regression analysis was used to assess factors associated with the between-eye SE difference. ResultsNinety-one participants (6–18 years of age; 52.75% girls) were included. The highly myopic eyes showed significantly lower LP (P < 0.001) and smaller ALR (P < 0.001) than the contralateral eyes, while no significant difference was found in central LT. In both eyes, ALR was significantly related to SE (P = 0.001 and P = 0.006, respectively); while LT was not associated with SE (P = 0.051 and P = 0.052, respectively). Paired-eye analysis showed that the between-eye difference in ALR was the only lenticular parameter significantly associated with the between-eye difference in SE (P = 0.005). ConclusionIn highly myopic eyes, the crystalline lens reduced total power but morphologically changed to a more curved shape without significant lens thinning, suggesting that the LP loss is mainly achieved by reducing its internal power in high myopes.

Intraocular pressure assessment after dorzolamide and travoprost administration in a cat with bilateral posterior lens subluxation

Lens subluxation is mainly produced by the interruption, damage or degeneration of the suspension system of the zonules. In the case of felines, the primary etiology responsible for the appearance of this pathology is represented by anterior uveitis preceding the moment of diagnosis, often complicated by secondary glaucoma.