Posterior Lens Surface Research Articles

Rare case of anterior lenticonus

A 17-year-old girl presented with defective vision in both eyes. On ocular examination, she showed anterior lenticonus in both eyes with normal fundus and an “oil droplet reflex” on retroillumination (Fig. A, B). Lenticonus is characterized by conical protrusion of the anterior or posterior lens surface. Posterior lenticonus is more common than anterior and is usually unilateral. Anterior lenticonus is often bilateral and is usually associated with Alport syndrome. Alport syndrome results in renal failure, which can be avoided by early diagnosis and prompt referral.

Viscodelamination of Localized Retrolental Plaques During Lens-Sparing Vitrectomy in Eyes With Pediatric Tractional Vitreoretinopathy.

To report viscodelamination of localized retrolental plaques during lens-sparing vitrectomy in eyes with pediatric tractional vitreoretinopathy. Viscodelamination of retrolental plaques was performed during 23-gauge lens-sparing vitrectomy in 11 eyes from 11 children with a median age (range) of 12 (4-58) months. There were five eyes with Stage 4 familial exudative vitreoretinopathy, one eye with Stage 4B retinopathy of prematurity, and five eyes with anterior-posterior persistent fetal vasculature syndrome. Retrolental plaques were separated from the posterior lens capsule by the tension of viscoelastic injection in the Berger's space. In 10 of 11 eyes, retrolental plaques were removed from posterior surface of lens without capsular tearing. During the 12-month to 18-month follow-up period, lens clarity along the visual axis was retained in 5 eyes with familial exudative vitreoretinopathy, one eye with retinopathy of prematurity, and 2 of 5 eyes with persistent fetal vasculature. Atraumatic viscodelamination was associated with retrolental plaques that did not incorporate into the posterior lens capsule. Retinal dragging was reversed in all 11 eyes. Viscodelamination may be effective for the dissection of retrolental plaques related to pediatric vitreoretinopathy in selected cases.

Panoramic Observation of Crystalline Lenses with 25 MHz Ultrasonography.

Purpose To visualize and assess in vivo the age-related changes in crystalline lens size and contour. Methods Seventy-nine healthy volunteers, 39 females and 40 males, with a mean age of 41.53 + 11.32 years (range: 21 to 60 years) were enrolled in this study. The axial lens thickness (ALT), equatorial lens diameter (ELD), and anterior (Ra) and posterior (Rp) lens surface radii of curvatures of the subjects' left eyes were measured with a 25 MHz ultrasound probe. Results The mean ALT and ELD were 4.178 mm + 0.288 mm and 9.209 mm + 0.214 mm, respectively. There was a statistically significant increase in both ALT (slope = 11 μm/year, r = 0.88, p < 0.01) and ELD (slope = 6 μm/year, r = 0.60, p < 0.01) with age. Ra negatively correlated, and Rp did not change with age. Conclusion There were no statistically significant relationships between any studied values and gender. Independent of gender, the lens grows equatorially and axially with age while its central anterior lens surface steepens and its posterior central surface curvature does not change.

Off-axis optical coherence tomography imaging of the crystalline lens to reconstruct the gradient refractive index using optical methods.

Earlier studies have shown that the gradient index of refraction (GRIN) of the crystalline lens can be reconstructed in vitro using Optical Coherence Tomography (OCT) images. However, the methodology cannot be extended in vivo because it requires accurate measurements of the external geometry of the lens. Specifically, the posterior surface is measured by flipping the lens so that the posterior lens surface faces the OCT beam, a method that cannot be implemented in vivo. When the posterior surface is imaged through the lens in its natural position, it appears distorted by the unknown GRIN. In this study, we demonstrate a method to reconstruct both the GRIN and the posterior surface shape without the need to flip the lens by applying optimization routines using both on-axis and off-axis OCT images of cynomolgous monkey crystalline lenses, obtained by rotating the OCT delivery probe from -45 to +45 degrees in 5 degree steps. We found that the GRIN profile parameters can be reconstructed with precisions up to 0.009, 0.004, 1.7 and 1.1 (nucleus and surface refractive indices, and axial and meridional power law, respectively), the radius of curvature within 0.089 mm and the conic constant within 0.3. While the method was applied on isolated crystalline lenses, it paves the way to in vivo lens GRIN and posterior lens surface reconstruction.

Anterior Segment Biometry with Phenylephrine and Tropicamide during Accommodation Imaged with Ultralong Scan Depth Optical Coherence Tomography.

Purpose To investigate the influence of phenylephrine and tropicamide on anterior segment biometry with ultralong scan depth optical coherence tomography (UL-OCT) during accommodation. Methods In this study, 20 left eyes of healthy volunteers with a mean ± standard deviation age of 31.05 ± 5.84 years and a mean refraction of −1.16 ± 1.11 diopters (range 0∼−3.0 D) were imaged using UL-OCT after instillation of artificial tears, phenylephrine, and tropicamide in three follow-up trials, respectively. At each follow-up trial, two repeated measurements were performed at states of relax and 5D accommodative stimulation. The dimensional parameters included central corneal thickness (CCT), anterior chamber depth (ACD), pupil diameter (PD), lens thickness (LT), and horizontal radii of the lens anterior and posterior surface curvatures (LAC and LPC). Results Tropicamide led to larger pupil, deeper ACD, thinner LT, and flatter crystalline lens surface (P < 0.05). Phenylephrine induced an increase in PD (P < 0.05), while no significant changes were seen in ACD, LT, LAC, and LPC (P > 0.05). CCT did not change after both phenylephrine and tropicamide instillation in this study (P > 0.05). Tropicamide induced the loss of accommodation and phenylephrine achieved pupil dilation without affecting the accommodation. PD, ACD decreased, LT increased significantly and the anterior and posterior surface of the lens in a 6.294 mm of diameter optical zone became steeper during accommodation after administration of phenylephrine (P < 0.05). Conclusion The anterior segment physiology changed after tropicamide instillation. Besides, tropicamide induced the loss of accommodation and phenylephrine preserved the accommodation with a larger pupil. And, the anterior and posterior surface of lens in a 6.294 mm of diameter optical zone became steeper during the accommodation.

Optical Coherence Tomography Reveals Sigmoidal Crystalline Lens Changes during Accommodation.

This study aimed to quantify biometric modifications of the anterior segment (AS) during accommodation and to compare them against changes in both accommodative demand and response. Thirty adults, aged 18–25 years were rendered functionally emmetropic with contact lenses. AS optical coherence tomography (AS-OCT) images were captured along the 180° meridian (Visante, Zeiss Meditec, Jena, Germany) under stimulated accommodative demands (0–4 D). Images were analysed and lens thickness (LT) was measured, applying a refractive index correction of 1.00. Accommodative responses were also measured sequentially through a Badal optical system fitted to an autorefractor (Shin Nippon NVision-K 5001, Rexxam, Japan). Data were compared with Dubbelman schematic eye calculations. Significant changes occurred in LT, anterior chamber depth (ACD), lens centroid (i.e., ACD + LT/2), and AS length (ASL = ACD + LT) with accommodation (all p < 0.01). There was no significant change in CT with accommodation (p = 0.81). Measured CT, ACD, and lens centroid values were similar to Dubbelman modelled parameters, however AS-OCT overestimated LT and ASL. As expected, the accommodative response was less than the demand. Interestingly, up until approximately 1.5 D of response (2.0 D demand), the anterior crystalline lens surface appears to be the primary correlate. Beyond this point, the posterior lens surface moves posteriorly resulting in an over-all sigmoidal trajectory. he posterior crystalline lens surface demonstrates a sigmoidal response with increasing accommodative effort.

The Relationship Between High-Order Aberration and Anterior Ocular Biometry During Accommodation in Young Healthy Adults.

PurposeThis study investigated the anterior ocular anatomic origin of high-order aberration (HOA) components using optical coherence tomography and a Shack-Hartmann wavefront sensor.MethodsA customized system was built to simultaneously capture images of ocular wavefront aberrations and anterior ocular biometry. Relaxed, 2-diopter (D) and 4-D accommodative states were repeatedly measured in 30 young subjects. Custom software was used to correct optical distortions and measure biometric parameters from the images.ResultsThe anterior ocular biometry changed during 2-D accommodation, in which central lens thickness, ciliary muscle thicknesses at 1 mm posterior to the scleral spur (CMT1), and the maximum value of ciliary muscle thickness increased significantly, whereas anterior chamber depth, CMT3, radius of anterior lens surface curvature (RAL), and radius of posterior lens surface curvature (RPL) decreased significantly. The changes in the anterior ocular parameters during 4-D accommodation were similar to those for the 2-D accommodation. newcommand{bialpha}{boldsymbol{alpha}}newcommand{bibeta}{boldsymbol{beta}}newcommand{bigamma}{boldsymbol{gamma}}newcommand{bidelta}{boldsymbol{delta}}newcommand{bivarepsilon}{boldsymbol{varepsilon}}newcommand{bizeta}{boldsymbol{zeta}}newcommand{bieta}{boldsymbol{eta}}newcommand{bitheta}{boldsymbol{theta}}newcommand{biiota}{boldsymbol{iota}}newcommand{bikappa}{boldsymbol{kappa}}newcommand{bilambda}{boldsymbol{lambda}}newcommand{bimu}{boldsymbol{mu}}newcommand{binu}{boldsymbol{nu}}newcommand{bixi}{boldsymbol{xi}}newcommand{biomicron}{boldsymbol{micron}}newcommand{bipi}{boldsymbol{pi}}newcommand{birho}{boldsymbol{rho}}newcommand{bisigma}{boldsymbol{sigma}}newcommand{bitau}{boldsymbol{tau}}newcommand{biupsilon}{boldsymbol{upsilon}}newcommand{biphi}{boldsymbol{phi}}newcommand{bichi}{boldsymbol{chi}}newcommand{bipsi}{boldsymbol{psi}}newcommand{biomega}{boldsymbol{omega}}({rm Z}_4^0) decreased significantly during 2-D accommodation, and newcommand{bialpha}{boldsymbol{alpha}}newcommand{bibeta}{boldsymbol{beta}}newcommand{bigamma}{boldsymbol{gamma}}newcommand{bidelta}{boldsymbol{delta}}newcommand{bivarepsilon}{boldsymbol{varepsilon}}newcommand{bizeta}{boldsymbol{zeta}}newcommand{bieta}{boldsymbol{eta}}newcommand{bitheta}{boldsymbol{theta}}newcommand{biiota}{boldsymbol{iota}}newcommand{bikappa}{boldsymbol{kappa}}newcommand{bilambda}{boldsymbol{lambda}}newcommand{bimu}{boldsymbol{mu}}newcommand{binu}{boldsymbol{nu}}newcommand{bixi}{boldsymbol{xi}}newcommand{biomicron}{boldsymbol{micron}}newcommand{bipi}{boldsymbol{pi}}newcommand{birho}{boldsymbol{rho}}newcommand{bisigma}{boldsymbol{sigma}}newcommand{bitau}{boldsymbol{tau}}newcommand{biupsilon}{boldsymbol{upsilon}}newcommand{biphi}{boldsymbol{phi}}newcommand{bichi}{boldsymbol{chi}}newcommand{bipsi}{boldsymbol{psi}}newcommand{biomega}{boldsymbol{omega}}({rm{Z}}_3^{ - 1}), newcommand{bialpha}{boldsymbol{alpha}}newcommand{bibeta}{boldsymbol{beta}}newcommand{bigamma}{boldsymbol{gamma}}newcommand{bidelta}{boldsymbol{delta}}newcommand{bivarepsilon}{boldsymbol{varepsilon}}newcommand{bizeta}{boldsymbol{zeta}}newcommand{bieta}{boldsymbol{eta}}newcommand{bitheta}{boldsymbol{theta}}newcommand{biiota}{boldsymbol{iota}}newcommand{bikappa}{boldsymbol{kappa}}newcommand{bilambda}{boldsymbol{lambda}}newcommand{bimu}{boldsymbol{mu}}newcommand{binu}{boldsymbol{nu}}newcommand{bixi}{boldsymbol{xi}}newcommand{biomicron}{boldsymbol{micron}}newcommand{bipi}{boldsymbol{pi}}newcommand{birho}{boldsymbol{rho}}newcommand{bisigma}{boldsymbol{sigma}}newcommand{bitau}{boldsymbol{tau}}newcommand{biupsilon}{boldsymbol{upsilon}}newcommand{biphi}{boldsymbol{phi}}newcommand{bichi}{boldsymbol{chi}}newcommand{bipsi}{boldsymbol{psi}}newcommand{biomega}{boldsymbol{omega}}({rm{Z}}_3^1), newcommand{bialpha}{boldsymbol{alpha}}newcommand{bibeta}{boldsymbol{beta}}newcommand{bigamma}{boldsymbol{gamma}}newcommand{bidelta}{boldsymbol{delta}}newcommand{bivarepsilon}{boldsymbol{varepsilon}}newcommand{bizeta}{boldsymbol{zeta}}newcommand{bieta}{boldsymbol{eta}}newcommand{bitheta}{boldsymbol{theta}}newcommand{biiota}{boldsymbol{iota}}newcommand{bikappa}{boldsymbol{kappa}}newcommand{bilambda}{boldsymbol{lambda}}newcommand{bimu}{boldsymbol{mu}}newcommand{binu}{boldsymbol{nu}}newcommand{bixi}{boldsymbol{xi}}newcommand{biomicron}{boldsymbol{micron}}newcommand{bipi}{boldsymbol{pi}}newcommand{birho}{boldsymbol{rho}}newcommand{bisigma}{boldsymbol{sigma}}newcommand{bitau}{boldsymbol{tau}}newcommand{biupsilon}{boldsymbol{upsilon}}newcommand{biphi}{boldsymbol{phi}}newcommand{bichi}{boldsymbol{chi}}newcommand{bipsi}{boldsymbol{psi}}newcommand{biomega}{boldsymbol{omega}}({rm{Z}}_4^0), and newcommand{bialpha}{boldsymbol{alpha}}newcommand{bibeta}{boldsymbol{beta}}newcommand{bigamma}{boldsymbol{gamma}}newcommand{bidelta}{boldsymbol{delta}}newcommand{bivarepsilon}{boldsymbol{varepsilon}}newcommand{bizeta}{boldsymbol{zeta}}newcommand{bieta}{boldsymbol{eta}}newcommand{bitheta}{boldsymbol{theta}}newcommand{biiota}{boldsymbol{iota}}newcommand{bikappa}{boldsymbol{kappa}}newcommand{bilambda}{boldsymbol{lambda}}newcommand{bimu}{boldsymbol{mu}}newcommand{binu}{boldsymbol{nu}}newcommand{bixi}{boldsymbol{xi}}newcommand{biomicron}{boldsymbol{micron}}newcommand{bipi}{boldsymbol{pi}}newcommand{birho}{boldsymbol{rho}}newcommand{bisigma}{boldsymbol{sigma}}newcommand{bitau}{boldsymbol{tau}}newcommand{biupsilon}{boldsymbol{upsilon}}newcommand{biphi}{boldsymbol{phi}}newcommand{bichi}{boldsymbol{chi}}newcommand{bipsi}{boldsymbol{psi}}newcommand{biomega}{boldsymbol{omega}}({rm{Z}}_6^0) shifted to negative values during 4-D accommodation. The change in newcommand{bialpha}{boldsymbol{alpha}}newcommand{bibeta}{boldsymbol{beta}}newcommand{bigamma}{boldsymbol{gamma}}newcommand{bidelta}{boldsymbol{delta}}newcommand{bivarepsilon}{boldsymbol{varepsilon}}newcommand{bizeta}{boldsymbol{zeta}}newcommand{bieta}{boldsymbol{eta}}newcommand{bitheta}{boldsymbol{theta}}newcommand{biiota}{boldsymbol{iota}}newcommand{bikappa}{boldsymbol{kappa}}newcommand{bilambda}{boldsymbol{lambda}}newcommand{bimu}{boldsymbol{mu}}newcommand{binu}{boldsymbol{nu}}newcommand{bixi}{boldsymbol{xi}}newcommand{biomicron}{boldsymbol{micron}}newcommand{bipi}{boldsymbol{pi}}newcommand{birho}{boldsymbol{rho}}newcommand{bisigma}{boldsymbol{sigma}}newcommand{bitau}{boldsymbol{tau}}newcommand{biupsilon}{boldsymbol{upsilon}}newcommand{biphi}{boldsymbol{phi}}newcommand{bichi}{boldsymbol{chi}}newcommand{bipsi}{boldsymbol{psi}}newcommand{biomega}{boldsymbol{omega}}({rm{Z}}_4^0) negatively correlated with those in CMT1, and the negative change in newcommand{bialpha}{boldsymbol{alpha}}newcommand{bibeta}{boldsymbol{beta}}newcommand{bigamma}{boldsymbol{gamma}}newcommand{bidelta}{boldsymbol{delta}}newcommand{bivarepsilon}{boldsymbol{varepsilon}}newcommand{bizeta}{boldsymbol{zeta}}newcommand{bieta}{boldsymbol{eta}}newcommand{bitheta}{boldsymbol{theta}}newcommand{biiota}{boldsymbol{iota}}newcommand{bikappa}{boldsymbol{kappa}}newcommand{bilambda}{boldsymbol{lambda}}newcommand{bimu}{boldsymbol{mu}}newcommand{binu}{boldsymbol{nu}}newcommand{bixi}{boldsymbol{xi}}newcommand{biomicron}{boldsymbol{micron}}newcommand{bipi}{boldsymbol{pi}}newcommand{birho}{boldsymbol{rho}}newcommand{bisigma}{boldsymbol{sigma}}newcommand{bitau}{boldsymbol{tau}}newcommand{biupsilon}{boldsymbol{upsilon}}newcommand{biphi}{boldsymbol{phi}}newcommand{bichi}{boldsymbol{chi}}newcommand{bipsi}{boldsymbol{psi}}newcommand{biomega}{boldsymbol{omega}}({rm{Z}}_3^1) correlated with changes in RAL and CMT1.ConclusionsHOA components altered during step-controlled accommodative stimuli. Ciliary muscle first contracted during stepwise accommodation, which may directly contribute to the reduction of spherical aberration (SA). The lens morphology was then altered, and the change in anterior lens surface curvature was related to the variation of coma.

Antimicrobial Efficacy of Contact Lens Care Solutions Against Neutrophil-Enhanced Bacterial Biofilms.

PurposeNeutrophil-derived extracellular debris has been shown to accelerate bacterial biofilm formation on hydrogel and silicone hydrogel contact lens surfaces compared to lenses inoculated with bacteria alone. The purpose of this study was to evaluate the disinfection efficacy of four standard commercial contact lens cleaning regimens against neutrophil-enhanced bacterial biofilms formed on silicone hydrogel contact lenses.MethodsFour reference strains were used: Pseudomonas aeruginosa, Serratia marcescens, Stenotrophomonas maltophilia, and Staphylococcus aureus. Human neutrophils were isolated from peripheral blood by venipuncture. Unworn Lotrafilcon B lenses were incubated overnight in each respective strain with stimulated neutrophils. Contact lenses were then cleaned using one of four contact lens care solutions according to manufacturer instructions. Bacterial viability was assessed by colony counts and confocal microscopy. Volume of residual debris on lens surfaces after cleaning was quantified using IMARIS software.ResultsAll four solutions tested showed effective antimicrobial activity against each bacterial strain; however, substantial amounts of nonviable bacteria and cellular debris remained on the lens surface despite concomitant digital cleaning.ConclusionsNecrotic cellular debris that accumulates under the posterior lens surface during wear of an inoculated contact lens is not fully removed during routine cleaning and disinfection.Translational RelevanceThe accumulation of residual cellular debris on the contact lens surface may contribute to new colonization of the lens and represents a significant risk factor for a contact lens–related adverse event. Additional studies are needed to correlate these findings with risk for corneal infiltrative and/or infectious events in a standard animal model.

Анатомо-топографические особенности передних кортикальных слоев стекловидного тела

Introduction. The vitreous body (VB) is limited by anterior cortex (AC) layers, consisting of densely interconnected collagen fibers. There is no consensus regarding the structural AC organization and its relationship with the structures of the eyeball. Purpose. To study the anatomical and topographical features of the anterior cortical layers of VB. Material and methods . We developed an original method for contrasting the VB structures using an ultra-fine Vitreokontrast suspension based on a water-insoluble inorganic salt of barium sulfate in the isotonic solution. The study was performed in 20 cadaveric donor eyes. the original technology. Dissection was carried out according to a proposed original technology. The scleral incision was made at a 4mm distance from the limbus along the circumference. Then we cut the sclera between the rectus muscles, then the petals of choroid and retina were formed, and also they were cut off. Then we cut the sclera between the rectus muscles, then the petals of choroid and retina were formed, and also cut them off. We stained the vitreous structures using the Vitreokontrast suspension with a sequential removal of the anterior cortex up to the posterior lens capsule. Results. After the cortex removal in the cadaveric donor eyes several membranous structures (on an average of four) were detected with a covering the retrolental space with an ability to exfoliate, with sites of the attachment to the Wieger ligament and fibers of ciliary zonula and pars plana. After the removal of the membranous structures and their restaining a layer of vitreous fibers was contrasted on the posterior capsule of the lens in the area of Berger space projection. Conclusion . The study revealed no case of a true full anterior cortex detachment. The anterior cortex exfoliation occurred with the formation of a multilayer membranous structure, covering the posterior surface of lens and ciliary body. The presence of vitreous fibers closely associated with the posterior capsule of the lens in the projection area of Berger space, allows to suppose a possibility of retrolental bag existence, one of walls of which is associated with the posterior lens capsule.

Apply of RetCam Ⅱ and color Doppler imaging in persistent hyperplastic primary vitreous

To observe the manifestations of RetCam Ⅱ and color Doppler imaging (CDI) in a retrospective case series of persistent hyperplastic primary vitreous (PHPV). Retrospective study. The medical records of 9 eyes/9 patients with PHPV went through RetCamⅡ and CDI from 2009 to 2014. There were 6 young boys and 3 young girl in this study, age from 2 months to 5 years. All the patients were born at full term. 9 eyes had complication (cataract). The manifestations of RetCam Ⅱ: There were pale in optic disc. There were white fibre rod connected with optic disc, then prolonged to vitreous cavity, connected with posterior lens capsule. CDI showed arterial blood stream signal in band-shaped echogenic structure within vitreous cavity, prolonged to lens from the optic disc, or showed funnel-shaped echogenic mass at the posterior surface of lens and anterior of vitreous body, adhered to ciliary body, lens and the optic disc. PHPV is congenital ocular anomalies because of a failure of primary vitreous and the hyaloids vascular system to regress. It manifests as unilateral and boys. We diagnosis PHPV by RetCamⅡ and CDI.

Clinical Outcomes and Cataract Formation Rates in Eyes 10 Years After Posterior Phakic Lens Implantation for Myopia.

Intraocular collamer lenses (ICLs) are posterior chamber phakic lenses that provide a refractive surgery option for those with high myopia or astigmatism. The short-term and midterm results indicate good refraction stability, efficacy, and safety. Cataract has been suggested to be an important long-term complication of ICL implantation. To report the rates of cataract development and refractive outcomes 10 years after ICL implantation. The study included 133 eyes of 78 patients undergoing consecutive V4 model ICL implantations, which took place from January 1, 1998, through December 31, 2004, at Jules-Gonin Eye Hospital, Lausanne, Switzerland. Data analysis was performed from January 1, 2014, to May 31, 2014. The lenses implanted were as follows: 53 V4 model ICLs of -15.5 D or greater, 73 V4 model ICLs of less than -15.5 diopter (D), and 7 V4 model toric ICLs for myopia. Rate of cataract surgery, lens opacity, ocular hypertension, refractive safety, predictability, and stability. A total of 133 eyes of 78 patients (34 men and 44 women, with a mean [SD] age of 38.8 [9.2] years at enrollment) met the inclusion criteria. The rate of lens opacity development was 40.9% (95% CI, 32.7%-48.8%) and 54.8% (95% CI, 44.7%-63.0%) at 5 and 10 years, respectively. Phacoemulsification was performed in 5 eyes (4.9%; 95% CI, 1.0%-8.7%) and 18 eyes (18.3%; 95% CI, 10.1%-25.8%) at 5 and 10 years after ICL implantation, respectively. The vault height (distance between the posterior ICL surface and anterior lens surface) measured a mean (SD) of 426 (344) μm immediately postoperatively, decreasing to 213 (169) μm at 10 years. A smaller vault height was associated with the development of lens opacity and phacoemulsification (P = .005 and .008, respectively). The intraocular pressure was 15 mm Hg postoperatively, and there was no significant increase in intraocular pressure observed until the 10-year follow-up (16 mm Hg, P = .02). At 10 years, 12 eyes (12.9%; 95% CI, 5.6%-19.6%) had developed ocular hypertension that required topical medication. At 10 years, the mean (SD) safety index was 1.25 (0.57), with a manifest spherical equivalent of -0.5 D at 1-year postoperatively vs -0.7 D at 10 years postoperatively in eyes aimed at emmetropia. This retrospective single center study indicates that ICL implantation provides good long-term safety and stability of refraction in patients with high myopia compared with similar short-term studies. However, the rates of cataract formation and ocular hypertension at 10 years have important clinical implications, and as such this information should be part of the available patient information before ICL implantation.

Chronic Recurrent Pseudophakic Endophthalmitis

An immunocompetentwoman in her 80s underwent uncomplicated cataract surgery in her righteye4monthspriorwithbest-correctedvisualacuity (BCVA)of20/25OD.Twoweeks prior topresentation, shereportedagradual increase inblurredvisionwith intermittent floaters in the right eyebut deniedpain or inciting events.HerBCVAwas20/50OD. Therewere large keratic precipitates, 1+ anterior chamber cell and flare, and no hypopyon. Numerous white precipitates were noted on the anterior and posterior surface of a 3-piece posterior chamber intraocular lens (Figure, A). Therewere 2+ to 3+ anterior vitreous cells and a 2–disc area chorioretinal scar along the superior retinal arcadeswith extramacular drusen, but no areasof chorioretinitis (Figure, B). B-scanultrasonography showedaposterior vitreousdetachmentandmoderatevitreousopacities.Thecontralateralphakiceyeshowedsimilardrusen but was otherwise unremarkable. The patient underwent a vitreous tap,whichwas negative for organisms, aswell as injection of intravitreal vancomycin hydrochloride and ceftazidime in the right eye. Topical prednisolone acetate and ofloxacin were started 4 times daily, and steroids were increased toevery2hourswhile awakeat follow-up.HerBCVA improved to20/30OD4days later. TheBCVAremainedexcellent andkeraticprecipitatesdissipatedby 1monthof followup, with stable findings in the posterior pole. Topical antibiotics were stopped and topical steroidswere gradually tapered. At 2months’ follow-up, however, she had recurrent anterior chamber and vitreous inflammation with mild cystoid macular edema. Quiz at jamaophthalmology.com Fundus photograph B Slitlamp photograph A

Optical Coherence Tomography Imaging for Glaucoma - Today and Tomorrow.

Digital imaging technologies for glaucoma diagnostics have evolved rapidly over the recent years. From time-domain optical coherence tomography (OCT) to spectral-domain and swept-source OCTs, the application of OCT for analysis of the anterior chamber angle and the optic nerve head (ONH) is expanding. The second-generation anterior segment swept-source OCT is able to image the configuration of the anterior chamber angle in 3 dimensions in less than 1 second and perform 360-degree analysis of the anterior chamber angle width for detection of angle closure. The morphology, density, and dimensions of the crystalline lens in relation to the anterior chamber can now be examined from the anterior corneal surface to the posterior lens surface, facilitating the investigation of the involvement of the crystalline lens in primary angle closure. Spectral-domain and swept-source OCTs have improved the measurement reliability of the lamina cribrosa and the neuroretinal rim configurations. Studying the deformation of the lamina cribrosa and ONH surfaces is relevant to decipher the mechanisms of ONH damage in the development and progression of glaucoma. Software and algorithms for automatic analysis of the anterior chamber angle dimensions and deformation of the ONH and lamina cribrosa surfaces are required to process large volumetric data sets, and they are under active development. It is expected that new imaging technologies will improve the detection and risk assessment of angle-closure and open-angle glaucomas.

OCT-based crystalline lens topography in accommodating eyes.

Custom Spectral Domain Optical Coherence Tomography (SD-OCT) provided with automatic quantification and distortion correction algorithms was used to measure anterior and posterior crystalline lens surface elevation in accommodating eyes and to evaluate relationships between anterior segment surfaces. Nine young eyes were measured at different accommodative demands. Anterior and posterior lens radii of curvature decreased at a rate of 0.78 ± 0.18 and 0.13 ± 0.07 mm/D, anterior chamber depth decreased at 0.04 ± 0.01 mm/D and lens thickness increased at 0.04 ± 0.01 mm/D with accommodation. Three-dimensional surface elevations were estimated by subtracting best fitting spheres. In the relaxed state, the spherical term accounted for most of the surface irregularity in the anterior lens (47%) and astigmatism (70%) in the posterior lens. However, in accommodated lenses astigmatism was the predominant surface irregularity (90%) in the anterior lens. The RMS of high-order irregularities of the posterior lens surface was statistically significantly higher than that of the anterior lens surface (x2.02, p<0.0001). There was significant negative correlation in vertical coma (Z3 (-1)) and oblique trefoil (Z3 (-3)) between lens surfaces. The astigmatic angle showed high degree of alignment between corneal surfaces, moderate between corneal and anterior lens surface (~27 deg), but differed by ~80 deg between the anterior and posterior lens surfaces (including relative anterior/posterior lens astigmatic angle shifts (10-20 deg).

Scleral lenses in the management of exposure/neurotrophic keratopathy in patients with cranial nerve palsy

SummaryScleral lenses are increasingly being recognized as a viable option for management of exposure keratopathy. Unlike more aggressive surgical interventions, the lenses can provide complete protection of the ocular surface without compromising visual clarity or restricting visual field. Preservation of corneal epithelial integrity is of utmost importance when lid function is compromised or absent. The fluid reservoir between the posterior surface of a scleral lens and the anterior corneal surface provides continuous hydration of the corneal epithelium and allows for healing of any epithelial defects. Furthermore, the lens itself protects fragile epithelial tissue from shear forces arising from lid movement over the cornea during the blink. Preservation of visual function is also important for these patients. Those who suffer from decreased vision due to irregularity of a desiccated ocular surface frequently note improvement in visual function with scleral lens wear, because the lens provides a smooth optical surface and neutralizes any corneal irregularity. This presentation will review and summarize visual and ocular outcomes of scleral lens therapy for management of exposure keratopathy at the Mayo Clinic.

Pseudomonas aeruginosa Survival at Posterior Contact Lens Surfaces after Daily Wear.

Pseudomonas aeruginosa keratitis is a sight-threatening complication of contact lens wear, yet mechanisms by which lenses predispose to infection remain unclear. Here, we tested the hypothesis that tear fluid at the posterior contact lens surface can lose antimicrobial activity over time during lens wear. Daily disposable lenses were worn for 1, 2, 4, 6, or 8 hours immediately after removal from their packaging or after presoaking in sterile saline for 2 days to remove packaging solution. Unworn lenses were also tested, some coated in tears "aged" in vitro for 1 or 8 hours. Lenses were placed anterior surface down into tryptic soy agar cradles containing gentamicin (100 μg/mL) to kill bacteria already on the lens and posterior surfaces inoculated with gentamicin-resistant P. aeruginosa for 3 hours. Surviving bacteria were enumerated by viable counts of lens homogenates. Posterior surfaces of lenses worn by patients for 8 hours supported more P. aeruginosa growth than lenses worn for only 1 hour, if lenses were presoaked before wear (∼ 2.4-fold, p = 0.01). This increase was offset if lenses were not presoaked to remove packaging solution (p = 0.04 at 2 and 4 hours). Irrespective of presoaking, lenses worn for 8 hours showed more growth on their posterior surface than unworn lenses coated with tear fluid that was aged for 8 hours in vitro (∼ 8.6-fold, presoaked, p = 0.003; ∼ 5.4-fold from packaging solution, p = 0.004). Indeed, in vitro incubation did not impact tear antimicrobial activity. This study shows that postlens tear fluid can lose antimicrobial activity over time during contact lens wear, supporting the idea that efficient tear exchange under a lens is critical for homeostasis. Additional studies are needed to determine applicability to other lens types, wearing modalities, and relevance to contact lens-related infections.

The zonules selectively alter the shape of the lens during accommodation based on the location of their anchorage points.

To determine the role of anterior and posterior zonular tension on the optomechanical lens response during accommodation simulation. Ten eyes from nine hamadryas baboons (4.9 ± 0.7 years) and 20 eyes from 18 cynomolgus monkeys (5.4 ± 0.3 years) were dissected, leaving the lens, zonules, ciliary body, hyaloid membrane, anterior vitreous, and a segmented scleral rim intact. The lens preparation was mounted in a lens stretcher, and the outer scleral shell was displaced radially in a stepwise fashion. The load, lens, and ciliary body diameters, lens power, lens thickness, and the anterior and posterior radius of curvature were measured during stretching. The zonular fibers attached to either the posterior or anterior lens surface were then carefully transected and the experiment was repeated. Zonular transection was confirmed in four eyes via laser scanning confocal microscopy after immunostaining. The effect of zonular transection on the tissue response to stretching was quantified. Without anterior zonules, 48% and 97% of the changes in anterior and posterior radii are retained. Without posterior zonules, 81% and 67% of the changes in anterior and posterior radii are retained. The changes in lens shape were reduced after transecting either the anterior or posterior zonules; however, both surfaces still changed shape. While either the anterior or posterior zonules alone are capable of changing the shape of both lens surfaces, the anterior zonules have a greater effect on the anterior lens surface, and the posterior zonules have a greater effect on the posterior lens surface.

Pars plana vitrectomy for posterior surface calcification in a silicone intraocular lens in asteroid hyalosis - a report of mistaken identity?

Dear editor Mehta et al recently reported removal of dystrophic calcification on the posterior surface of a silicone intraocular lens (IOL) in a patient with asteroid hyalosis.1 In this case the authors used pars plana vitrectomy (PPV) to successfully remove calcified deposits. We have recently tried unsuccessfully to use PPV to treat an 86 year old patient with calcification of a silicone IOL in the presence of asteroid hyalosis. We chose to avoid IOL exchange due to a history of Fuchs endothelial dystrophy and glaucoma in the left eye, and a failed corneal graft in a rubeotic eye on the right. Our patient did not have an intact posterior capsule having been treated with Nd:YAG capsulotomy 2 years previously, before the calcification occurred. A 25 gauge pars plana vitrectomy was performed after attempting to remove the deposits unsuccessfully from the posterior surface of the IOL with Nd:YAG laser. It was felt that PPV would be less likely to cause corneal decompensation than IOL exchange. In contrast to the experience of Mehta et al1 we found that the vitrector was unable to effectively remove many of the calcified deposits even with high vacuum. Instead the use of microforceps and a silicone tipped flute were required to ‘polish’ the IOL deposits (see Supplementary Video). Although we were able to remove a significant amount of the calcification in this way, the results were ultimately disappointing due to smearing of the deposits which were found to be ‘putty-like’ in consistency. Although there was some improvement in the clarity of the IOL on retroillumination, the patient reported very limited improvement in vision (6/18 preoperatively to 6/12 immediately after surgery), and on transillumination the posterior surface was significantly smudged (Figure 1). Figure 1 Smudging of posterior surface of IOL on transillumination postoperatively. Mehta et al reported that initially their patient underwent an unsuccessful Nd:YAG capsulotomy, however it was not made clear whether the posterior capsule remained intact.1 It has previously been suggested that direct contact of the IOL with the vitreous cavity caused by Nd:YAG capsulotomy accelerates the deposition of calcification on silicone IOLs,2 and other authors of larger case series of this condition have reported it to be mostly found after initial Nd:YAG capsulotomy,3,4 although reports of dystrophic calcification in the presence of an intact capsule do exist.5 Given our experience, we are unclear whether the photo presented demonstrates typical fibrous capsular opacity, or calcification of the posterior capsule rather than a true case of dystrophic calcification of the IOL optic. We believe this is an important distinction to make since we feel that vitrectomy is only likely to be successful if the posterior capsule is intact. A similar case of this condition has been published recently by Ullman and Gupta.5 They also used vitrectomy to treat dystrophic calcification, but found it to be ineffective at removing established calcification on the posterior IOL surface on more than one occasion. They suggested using prophylactic PPV to treat dystrophic calcification at an early stage before symptoms become established. We believe that vitrectomy and surgical capsulectomy should be considered as an alternative to Nd:YAG capsulotomy where IOL calcification is not yet established. It is likely that opening a significantly calcified posterior capsule by Nd:YAG capsulotomy in the presence of asteroid hyalosis will lead to significant future IOL dystrophic calcification. In established calcification of a silicone IOL we feel that vitrectomy is of limited value and IOL exchange should remain the standard treatment.

OCT 3-D surface topography of isolated human crystalline lenses.

Quantitative 3-D Optical Coherence Tomography was used to measure surface topography of 36 isolated human lenses, and to evaluate the relationship between anterior and posterior lens surface shape and their changes with age. All lens surfaces were fitted to 6th order Zernike polynomials. Astigmatism was the predominant surface aberration in anterior and posterior lens surfaces (accounting for ~55% and ~63% of the variance respectively), followed by spherical terms, coma, trefoil and tetrafoil. The amount of anterior and posterior surface astigmatism did not vary significantly with age. The relative angle between anterior and posterior surface astigmatism axes was on average 36.5 deg, tended to decrease with age, and was >45 deg in 36.1% lenses. The anterior surface RMS spherical term, RMS coma and 3rd order RMS decreased significantly with age. In general, there was a statistically significant correlation between the 3rd and 4th order terms of the anterior and posterior surfaces. Understanding the coordination of anterior and posterior lens surface geometries and their topographical changes with age sheds light into the role of the lens in the optical properties of the eye and the lens aging mechanism.

Relative lens vault in subjects with angle closure.

BackgroundThe purpose of this study was to investigate the association of a novel biometric parameter, relative lens vault (LV), with primary angle-closure (PAC) and primary angle-closure glaucoma (PACG).MethodsWe evaluated 101 subjects with PAC (G) and 101 normal subjects that were age- and gender-matched. Based on anterior-segment optical coherence tomography scans, and using customized software, the anterior vault (AV) and LV were measured. They were defined as the maximum distances between the horizontal line connecting the two scleral spurs and the posterior corneal surface and anterior lens surface, respectively. The relative LV was calculated by dividing the LV by the AV.ResultsSignificant differences between PAC (G) eyes and normal eyes were found in the LV (1.06 ± 0.41 vs. 0.36 ± 0.37 mm, P < 0.001), relative LV (0.34 ± 0.23 vs. 0.11 ± 0.25, P < 0.001), and axial length (22.96 ± 0.94 vs. 24.02 ± 1.33 mm, P < 0.001). However, the two groups’ values of the AV relative to those of axial length were quite similar (both 0.14 ± 0.03, P = 0.91). The relative LV values distinguished between PAC (G) eyes and normal eyes better than the LV values (area under the receiver operator characteristic curve: 0.97 vs. 0.92, P = 0.032).ConclusionsOur results suggest that relative dimensions of the eyeball’s anterior portion in PAC (G) eyes might be within the normal range. And the value of LV relative to that of the AV (i.e., the relative LV) is more closely related to PAC (G) than is the absolute value of LV.