Juvenile ocular abnormalities in a litter of black-footed ferrets

OBJECTIVE

To describe the clinical and histopathological features of ocular abnormalities noted in a litter of black-footed ferrets (Mustela nigripes), including corneal opacification, cataracts, persistent pupillary membranes, microphthalmia, symblepharon and anterior segment malformation.

ANIMALS STUDIED

A litter of eight black-footed ferrets examined at 10 weeks old with a history of ophthalmia neonatorum first noted at 7 days old and histopathological examination of three globes from three ferrets of the same litter between 5 and 7 months old following routine subconjunctival enucleation.

PROCEDURES

Due to the fractious nature of black-footed ferrets, slit-lamp biomicroscopic examination was performed under general isoflurane anesthesia at 10 weeks of age. Corneal opacification was noted in 9/16 eyes, cataracts in 4/16 eyes, and persistent pupillary membranes in 3/16 eyes, among other findings. Histopathology revealed persistent pupillary membranes and Descemet's membrane abnormalities consistent with congenital anterior segment malformation in all three globes. In one ferret, a posterior cortical cataract with posterior lenticular malformation and lens capsule discontinuity was noted. Purulent discharge was cultured at time of enucleation in one ferret with growth of E. coli.

CONCLUSIONS

A novel constellation of ocular malformations with primary congenital and secondary to ophthalmia neonatorum etiologies is described in black-footed ferrets. Due to endangered status of black-footed ferrets, small genetic pool and the requirement for adequate vision for wild-release, congenital ocular abnormalities such as anterior segment malformation and likely the cataracts described are of particular concern. Further investigation and monitoring are warranted to determine the heritability of these ocular abnormalities.

Biallelic novel variants in ZNF469 causing Brittle Cornea Syndrome 1: a detailed report of an Indian patient

BACKGROUND

Variations in ZNF469 have been associated with Brittle Cornea Syndrome that presents with bluish sclera, loss of vision after trivial trauma, arachnodactyly, and joint laxity.

MATERIALS AND METHODS

Detailed medical and family history, physical examination, and molecular analysis.

RESULTS

A 21-year-old female presented with bluish discoloration of sclera, diminution of vision following trivial trauma in childhood along with hearing loss and systemic features of arachnodactyly and joint laxity. Clinical diagnosis of brittle cornea syndrome was made which was molecularly proven using next-generation sequencing which identified compound heterozygosity in ZNF469 for pathogenic and likely pathogenic nonsense variants. One variant namely NM_001367624.2:c.5882dup was identified in the exon 3 which was novel and classified as likely pathogenic according to American College of Medical Genetics (ACMG) criteria for variant classification. Another variant NM_001367624.2:c.8992C>T in the exon 2 was classified as pathogenic for Brittle Cornea Syndrome 1.

CONCLUSIONS

The report adds to the allelic heterogeneity in ZNF469 causative of Brittle Cornea Syndrome 1 and shall acquaint the physicians about this potentially vision threatening, underdiagnosed, rare syndrome.

Analysis of clinical characteristics and factors influencing herpes simplex virus keratitis

Objective

To investigate the clinical characteristics and factors associated with herpes simplex virus keratitis.

Methods

Patients with herpes simplex virus keratitis who came to our hospital from January 2018 to June 2022 were selected and divided into a good prognosis group and a poor prognosis group according to their prognosis. The clinical data of the two groups were compared, and univariate/multivariate logistic regression was used to analyze the factors influencing the poor prognosis of herpes simplex virus keratitis.

Results

A one-way analysis of variance showed that, compared with the good prognosis group, the poor prognosis group had more elderly patients and a longer course of disease, and the difference was statistically significant (p < 0.05). There were significant differences in the types of patients between the two groups (p < 0.05). Univariate logistic regression analysis also showed that age (≥65 years) (OR: 1.557, 95%CI: 1.081-2.183, p < 0.05), course of disease (> 7 months) (OR: 1.303, 95%CI: 1.003-1.829, p < 0.05), epithelial type (OR: 2.321, 95%CI: 1.198-4.321, p < 0.05), and stromal type (OR: 2.536, 95%CI: 1.672-3.871, p < 0.05) were risk factors for poor prognosis. Multivariate logistic regression analysis showed that age (≥65 years) (OR: 1.656, 95%CI: 1.168-2.357, p < 0.05) and course of disease (> 7 months) (OR: 1.461, 95%CI: 1.031-2.001, p < 0.05) were independent risk factors for the prognosis of herpes simplex keratitis.

Conclusion

The clinical symptoms of herpes simplex virus keratitis include corneal opacity, corneal posterior elastic layer folds, corneal infiltration, posterior corneal mass, corneal edema, and ocular pain. Age and course of disease are important factors in the prognosis of herpes simplex virus keratitis.

Corneal Copper Deposition Secondary to Monoclonal Gammopathy in a Patient With Chronic Lymphocytic Leukemia: A Case Report

Hypercupremia-induced corneal copper deposition secondary to monoclonal gammopathy is rare and shows a characteristic corneal opacity quite different from other causes of hypercupremia, such as Wilson's disease. This report describes a case of corneal copper deposition in a patient with monoclonal gammopathy associated with chronic lymphocytic leukemia. An 84-year-old man with slowly progressive corneal opacity was referred to our hospital. The corneal opacity was present at least five years ago. The patient's best-corrected visual acuity was 20/25 OU (in both eyes) at the initial visit to our hospital. Slit-lamp examination and anterior segment optical coherence tomography revealed bilateral brown-colored opacity localized to deep layers of the central cornea. In vivo confocal microscopy (IVCM) showed indistinct corneal stromal cells in the deep layer and endothelial cells. The possible differential diagnoses were corneal dystrophy and Wilson's disease, but the color, shape, or site of corneal opacity was inconsistent with the disease. As the patient had a history of chronic lymphocytic leukemia, which is often associated with monoclonal gammopathy, we suspected that the corneal opacity was copper deposition in association with the hematologic diseases. Laboratory examinations showed elevated serum copper and normal ceruloplasmin. Serum protein electrophoresis revealed significantly high IgG levels with depression of IgA, IgE, and IgM. These results supported our diagnosis. Followingly, we consulted the patient's attending hematologist, and the doctor initiated treatment for hypercupremia. In conclusion, hypercupremia secondary to monoclonal gammopathy should be considered a possible cause of central brown-colored corneal opacity.

Inflammatory Cells and Lipid Deposits Detected by in Vivo Confocal Microscopy in Brimonidine Tartrate Ophthalmic Solution-Related Corneal Disorders: A Case Series

We reviewed the medical charts of five patients diagnosed with brimonidine tartrate (BT)-related corneal disorders. A fan-shaped corneal opacity was present in four patients and limbal corneal infiltrations were present in one patient. In vivo confocal microscopy revealed dendritic cells and lipid deposits in the fan-shaped opacity as well as neutrophils in limbal infiltrations. BT instillation was discontinued and topical administration of a corticosteroid was initiated for all patients. The limbal infiltrations improved after BT discontinuation. Conversely, the fan-shaped opacity remained in all affected patients. After a fan-shaped opacity has developed in a patient with a BT-related corneal disorder, the lesion is difficult to resolve. However, limbal infiltrations respond well to treatment. Therefore, BT should be discontinued and anti-inflammatory treatment initiated before a fan-shaped opacity forms.

Changes in the Parameters of Visual Evoked Potentials in Media Opacities

Purpose

This study compared flash visual evoked potentials (VEPs) parameter differences between eyes with unilateral opaque media and their normal contralateral counterparts.

Patients and Methods

We included 178 patients with unilateral media opacity and normal contralateral eye in each patient. The diseased eyes had normal ultrasonographic findings and were candidates for keratoplasty or anterior segment reconstruction. The patients underwent electrophysiological testing by the flash VEPs recording with the use of 1.4Hz (transient) and 8Hz (flicker) frequencies.

Results

The medians of P2 implicit times were significantly higher in eyes with media opacity than in normal eyes, with median differences between both eyes of -6.7 ms. Furthermore, the median N2P2 amplitude was 9.70 µv with media opacity compared with 11.00 µv in the normal eyes, with a significant difference of 1.3 (p = 0.002). The flash VEPs median parameters recorded at a frequency of 8-Hz showed significant differences in medians of spectral plots of 0.6 µv between normal and abnormal eyes. The same for the signal-to-noise ratio, where the difference in medians was 3 dB. Analysis of the difference between both eyes (normal-abnormal) in each patient showed in P2 implicit time a difference range of -49 to 54.7 ms with a median difference of -3 ms. The difference in amplitudes of recorded N2P2 showed a median of 2.13 µv. There was a statistically significant but weak negative correlation between N2P2 amplitude (r spearman = -0.173, p = 0.021) and the grades of corneal opacity.

Conclusion

Preoperative flash VEPs recording is useful for evaluating visual function in patients with unilateral media opacity to determine the future benefits of keratoplasty or anterior segment reconstruction. There are no correlations between the flash VEP parameters or the difference between the 2 eyes and the grades of corneal opacity.

Birefringence analysis of collagen supraorganization in cat corneas with tropical keratopathy

OBJECTIVE

To evaluate the birefringent properties of the cornea and examine the supraorganizational aspects of collagen fibers in cats with tropical keratopathy.

PROCEDURE

In this study, 10-micrometer-thick sections of corneal tissue from cats with tropical keratopathy were examined, both in the opaque and transparent areas of the anterior stroma. Control samples were obtained from healthy cat corneas. Polarized light microscopy was employed to evaluate the birefringent properties using two distinct methods. The first method involved measuring the optical retardation associated with corneal birefringence, while the second method assessed the alignment/waviness of the birefringent collagen fibers. Differences were significant when p < .05.

RESULTS

Tropical keratopathy resulted in a significant rise (p < .05) in optical retardation in both opaque and transparent regions of the cat cornea. In the anterior stroma, both the opaque zones and transparent tissue exhibited a higher degree of collagen fiber packing than the control corneas. However, no significant differences (p > .05) in alignment were observed between the transparent tissue of the diseased cornea and the healthy corneas.

CONCLUSION

Supraorganizational changes in collagen fiber packing are not restricted to lesion zones in cat corneas affected by tropical keratopathy. Such alterations also occur in the corneal tissue of the anterior stroma adjoining the lesions. Therefore, it is plausible that the transparent tissue of the anterior stroma in corneas affected by the disease may have functional abnormalities, despite its macroscopic healthy appearance. Additional investigations are required to clarify the implications of these potential defects and their conceivable contribution to tropical keratopathy.

Treatment of immune-mediated keratitis (IMMK) in dogs with immunosuppressants observed with spectral domain optical coherence tomography (SD-OCT)

Two dogs presented with bilateral pattern-forming corneal opacity. Treatment with topical immunosuppressants was initiated after a complete ophthalmic examination. The response to treatment was assessed by analyzing serial images using slit-lamp biomicroscopy and spectral domain optical coherence tomography (SD-OCT). Both dogs responded to topical immunosuppressants; however, the lesions recurred once the treatment was abated or withdrawn. The most effective immunosuppressant in both dogs was 0.03% tacrolimus ointment. Early and continuous treatment with topical immunosuppressants may be necessary to improve corneal clarity and prevent scarring. SD-OCT could provide useful structural information regarding presumed immune-mediated keratitis and aid in monitoring treatment response.

Topical application of calcitonin gene-related peptide as a regenerative, antifibrotic, and immunomodulatory therapy for corneal injury

Calcitonin gene-related peptide (CGRP) is a multifunctional neuropeptide abundantly expressed by corneal nerves. Using a murine model of corneal mechanical injury, we found CGRP levels in the cornea to be significantly reduced after injury. Topical application of CGRP as an eye drop three times daily accelerates corneal epithelial wound closure, reduces corneal opacification, and prevents corneal edema after injury in vivo. We then used a series of in vitro and in vivo techniques to investigate the mechanisms underlying CGRP's functions. CGRP promotes corneal epithelial cell migration, proliferation, and the secretion of laminin. It reduces TGF-β1 signaling and prevents TGF-β1-mediated stromal fibroblast activation and tissue fibrosis. CGRP reduces corneal endothelial cell apoptosis and death, preserves cell density and morphology, and promotes their pump function, thus reducing edema. Lastly, CGRP reduces neutrophil infiltration, macrophage maturation, and the production of inflammatory cytokines in the cornea. Taken together, our results show that corneal nerve-derived CGRP plays a cyto-protective, pro-regenerative, anti-fibrotic, and anti-inflammatory role in corneal wound healing. Given that current treatment options for corneal injury and opacity are scarce, CGRP has significant therapeutic potential in this area of unmet medical needs. In addition, our results highlight the critical role of sensory nerves in ocular surface homeostasis and injury repair.

Functional Characteristics of Diverse PAX6 Mutations Associated with Isolated Foveal Hypoplasia

The human fovea is a specialized pit structure in the central retina. Foveal hypoplasia is a condition where the foveal pit does not fully develop, and it is associated with poor vision. Autosomal dominant isolated foveal hypoplasia (FVH1) is a rare condition of foveal hypoplasia (FH) that lacks any other ocular manifestations. FVH1 is associated with hypomorphic mutations in the PAX6 gene that encodes a sequence-specific DNA-binding transcription factor for morphogenesis and evolution of the eye. We report our findings in 17 patients with PAX6 mutations associated with FVH1 or FH with aniridia and corneal opacities. Patients with three mutations, p.V78E, p.V83F and p.R128H, in the C-terminal subdomain of the paired domain (CTS) consistently have severe FH. Luciferase assays for a single reporter containing a representative PAX6 binding site indicated that the transcriptional activities of these mutations were significantly reduced, comparable to that of the truncation mutation of p.G65Rfs*5. Patients with p.P20S in the N-terminal subdomain of the paired domain, and a patient with p.N365K in the proline-serine-threonine-rich domain (PSTD) had mild FH. A patient with p.Q255L in the homeodomain had severe FH. The P20S and Q255L mutants did not affect the transcriptional activity. Mutant N365K has a retained DNA-binding activity but a reduced transcriptional activity, due to a low PSTD transactivation. These findings demonstrated that mutations associated with FVH1 underlie a functional divergence between DNA-binding ability and transcriptional activity. We conclude that a wide range of mutations in the PAX6 gene is not limited to the CST region and are responsible for FVH1.

Bilateral Congenital Stromal Corneal Cysts: Report of a Unique Case

The purpose of this report is to provide a comprehensive account of an exceptional case involving the presentation of congenital rubella syndrome (CRS) in a newborn. Furthermore, it aims to document the successful regression of CRS through medical treatment alone. We present the case of a five-day-old infant who was referred to our facility as a CRS case. The patient presented with bilateral white corneal opacity, which was observed shortly after birth. The mother was diagnosed as rubella-positive during pregnancy. Upon the initial examination under anesthesia, both eyes exhibited central white corneal opacity accompanied by large intrastromal cysts. Although a few breaks in Descemet's membrane were observed in both eyes, there were no signs of vascularization or the presence of iridocorneal or lenticular-corneal adhesions. After undergoing medical treatment consisting of topical sodium chloride and steroids, the cysts in both eyes completely regressed. Subsequently, the patient underwent penetrating keratoplasty to further address the dense scar. This case enhances our comprehension of ophthalmological complications associated with CRS and provides valuable insights into alternative therapeutic approaches for corneal stromal cysts.

Systematic review and meta-analysis of childhood visual impairment in the Eastern Mediterranean Region

Background

Childhood visual impairment has a significant effect on social life, educational performance, and professional choices, and can lead to poverty.

Aims

To review the prevalence and causes of visual impairment among children aged 5-17 years in the Eastern Mediterranean Region (EMR).

Methods

This study was conducted in 2021 using the Preferred Reporting Items for Systematic reviews and Meta- Analyses (PRISMA) method. We searched Google Scholar, PubMed, Web of Science, Scopus, Index Medicus for the Eastern Mediterranean Region, and Medline for studies published between January 2000 and April 2020. The articles included were epidemiological studies of prevalence and causes of childhood visual impairment published in peer-reviewed journals.

Results

Of the 12 705 articles screened, 23 from 9 countries met the inclusion criteria. The pooled prevalence of uncorrected, presenting, and best-corrected childhood visual impairment was 11.57%, 8.34% and 1.21%, respectively. The most common causes of childhood visual impairment were refractive error (51.89%), amblyopia (11.15%), retinal disorders (3.90%), corneal opacity (3.0%), and cataract (1.88%). There was a highly significant heterogeneity between the studies (P < 0.0001).

Conclusion

The prevalence of visual impairment among children in the EMR was high, and the leading causes were uncorrected refractive error and amblyopia, which were avoidable. Access to eyecare services may help improve early diagnosis and treatment of preventable causes of childhood visual impairment.

Global trends in blindness and vision impairment due to corneal opacity 1984-2020: a meta-analysis

TOPIC

We provide global estimates of the prevalence of corneal blindness and vision impairment in adults 40 years and older and examine the burden by age, gender, and geographic region from 1984-2020.

CLINICAL RELEVANCE

Corneal opacities (CO) are among the top five causes of blindness worldwide, yet the global prevalence, regional differences, and risk factors are unclear.

METHODS

Abstracted data from the published literature and surveys were obtained from the Global Burden of Disease Vision Loss Expert Group. We supplemented this by an independent systematic literature search of PubMed, Embase, Web of Science, Scopus, and Cochrane. Studies that provided CO vision impairment data based on population-based surveys for subjects 40 years of age or older were included, for a total of 244. For each of the four outcomes of blindness and moderate to severe vision impairment (MSVI) caused by trachomatous and non-trachomatous CO (NTCO), time trends and differences in prevalence by region, age, and sex were evaluated using a Poisson log-linear model with a generalized estimating equation method. Age-standardized estimates of global prevalence of blindness and MSVI were calculated using the 2015 United Nations standard populations.

RESULTS

The global prevalence of blindness due to NTCO in those 40 years and older was 0.081% (95% CI=0.049% to 0.315%); MSVI was 0.130% (95% CI= 0.087% to 0.372%). There was a significant increase with age (prevalence rate ratio=2.15, 95% CI=1.99-2.32). Latin America and Europe had the lowest rates, with 2-8 fold higher rates of blindness/MSVI in the other regions. The global prevalence of blindness due to trachomatous CO in those 50 years and older was 0.013% (95% CI=0.006% to 0.043%); MSVI was 0.180% (95% CI=0.006% to 0.049%). Trachomatous CO blindness and MSVI increased with age and female gender, and rates were significantly higher in the African regions; a decrease in blindness rates over time was found (prevalence rate ratio estimate=0.91, 95% CI=0.86-0.96).

CONCLUSION

An estimated 5.5 million persons worldwide are bilaterally blind or with MSVI due to CO, with an additional 6.2 million unilaterally blind. Trachomatous CO blindness is declining over time, likely due to the massive scaleup of the global trachoma elimination program and overall socioeconomic development.

Relationship of Density, Depth, and Surface Irregularity of Superficial Corneal Opacification with Visual Acuity

PURPOSE

To explore the relationship between the density, depth, and surface irregularity of superficial corneal opacities and vision.

METHODS

This prospective imaging study included 19 patients with unilateral superficial corneal opacification due to scarring post-microbial keratitis. Each eye underwent an assessment of uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), contact lens corrected visual acuity (CLCVA), and Scheimpflug and anterior segment optical tomography imaging. Regression analysis was performed to detect the association between density, depth of scarring, and the surface irregularity in terms of higher order aberrations (HOA), and keratometry and UCVA, CLCVA, and the difference between BSCVA and CLCVA.

RESULTS

The mean logMAR UCVA, BSCVA, and CLCVA were 0.76, 0.35, and 0.28, respectively. The corneal scars had a mean thickness of 158.7 ± 61 µ and density of 65.73 ± 24.46 GSU. Bivariate analysis model for UCVA showed an association with Z₄² secondary astigmatism (p = 0.02), Z₄⁴ quadrafoil (p = 0.01), combined coma Z₃ ^± 1(p = 0.03), and combined HOA Z₃-Z₆ (p = 0.045), out of which Z₄⁴ Quadrafoil (p = 0.04) was most significant with multivariate analysis. Bivariate analysis for BCVA-CLVA showed association with Z₃¹ coma horizontal (p = 0.04), Z₃³ oblique trefoil (p = 0.02), Z₄⁰ primary spherical aberration (p = 0.008), and Z₅ ^- 5 (p = 0.007), out of which Z₃¹ horizontal coma (p = 0.04) and Z₄⁰ spherical aberration (p = 0.009) were significant on multivariate analysis. Change in densitometry, corneal thickness, epithelial:stromal reflectivity ratio, scar depth, and keratometry did not show any significant association with UCVA, BSCVA-CLCVA, or CLCVA.

CONCLUSION

In superficial corneal stromal scarring, deranged surface irregularity parameters like higher-order aberrations affect the final visual acuity more than the depth or density of the opacity.

Small incision lenticule extraction and femtosecond-assisted laser in situ keratomileusis in patients with deep corneal opacity: case series

AIM

To report the safety, efficacy, and accuracy of small-incision lenticule extraction (SMILE) or femtosecond-assisted laser in situ keratomileusis (FS-LASIK) for the correction of myopia or myopic astigmatism in patients with deep corneal opacity denoted by anterior segment optical coherence tomography (AS-OCT).

METHODS

Four patients with monocular corneal opacity (3 due to mechanical injury, 1 due to a firecracker wound) were recruited and treated with refractive surgery (3 for SMILE, 1 for FS-LASIK combined with limbal relaxing incision (LRI). Preoperative ocular manifestations, surgical details, postoperative visual outcomes, corneal opacity parameters, and corneal topography were analyzed.

RESULTS

Preoperatively, spherical diopter ranged from -3.0 D to -4.75 D with cylinder ranging from -0.75 to -5.0 D, and corrected distance visual acuity (CDVA) ranging from 20/25 to 20/20. One eye's corneal opacity was located in the central zone and three were in the mid-peripheral optical zone. Three patients underwent uneventful SMILE in both eyes, whilst one patient underwent FS-LASIK for high astigmatism in both eyes and LRI in the right eye. CDVA of the eye with corneal opacity ranged from 20/22 to 20/20 one to six weeks postoperatively. Two patients achieved better CDVA and no patients lost Snellen lines. The postoperative diopter was within ±0.75 D for all eyes. Significant edema existed above the corneal opacity in one eye and dissipated soon. No eccentric corneal topography or morphological anomaly of the corneal cap or flap was observed.

CONCLUSION

The cases demonstrate that SMILE or FS-LASIK is safe and effective to treat myopic astigmatism combined with deep corneal opacity lesions after comprehensive preoperative evaluation and appropriate candidate selection. FS-LASIK combined with LRI is also sufficient for correcting high astigmatism due to corneal scarring.

Peter's anomaly-A homeotic gene disorder

Peter's anomaly is a rare form of congenital anterior segment dysgenesis of the eye. Varying degrees of central corneal opacity and lenticulo-corneal or irido-corneal synechiae are the key hallmarks. The association of Peter's anomaly along with short stature, rhizomelia, broad short hands or brachydactyly, with facial dysmorphism, cleft lip, cleft palate, genitourinary and cardiovascular anomalies is a distinct and is often termed Peter's plus syndrome. Early detection is imperative to prevent sensory deprivation amblyopia. Glaucoma can be present at initial diagnosis or at any stage later, but treatment can be difficult. For the dense leukoma, corneal graft may be needed but visual prognosis is poor. Research focussing on gene editing and regenerative medicine using native corneal endothelial cells is ongoing.

Endoilluminator-aided cataract surgery in eyes with corneal opacity - A modified surgical approach

Background

Cataract and corneal blindness continue to be leading causes of reversible blindness in India. These can co-exist in a multitude of pathologies such as trauma, healed keratitis (old herpetic scar), chronic degenerative changes such as labrador keratopathy, bullous keratopathy, corneal dystrophies etc. Phacoemulsification in such eyes is rewarding to the patient in terms of minimal intervention, less risk of complications owing to reduced open sky time (as in case of combined keratoplasty), and better predictable visual outcomes. Approach to such eyes with poor visualisation is highly challenging.

Purpose

We illustrate a modified surgical technique of chandelier illumination through pars plana for cataract surgery in eyes with corneal opacity of varying grades.

Synopsis

Five patients with dense cataract and small pupils, associated with corneal opacity (leucomatous and macular grade) are described. Closed chamber phacoemulsification with intraocular lens with or without pupil expanders was performed assisted by 23 or 25 gauge pars plana chandelier illumination introduced in the vitreous cavity through a sclerotomy wound made prior to phacoemulsification in the inferotemporal quadrant.

Highlights

Chandelier illumination aids in reducing the light scatter that occurs due to corneal opacity. Ease of visualisation of lens structures and of performing cataract surgery was noticed. One case was combined with penetrating keratoplasty with reduced open sky time. This assisted technique has advantages such as enhancing visualisation intraoperatively and allowing working in closed chamber. Its self-retaining nature aids bimanual manipulation. No complications were encountered. The video highlights the utility, advantages and practicality of chandelier retroillumination in patients with corneal opacities of varying degree undergoing phacoemulsification.

Video Link

https://youtu.be/I3z6QG-_wD8.

A novel approach in diagnosing multiple dentigerous cysts using CBCT illustration indicative of Mucopolysaccharidosis VI - a case report

Mucopolysaccharidosis VI is a genetic disorder affecting multiple organs with sundry clinical presentations. The main etiological factor reflects the disturbances in mucopolysaccharide metabolism leading to deposition of acid mucopolysaccharide in various tissues. The pathognomonic features of the disease include a large head, short neck, corneal opacity, open mouth associated with an enlarged tongue, enlargement of the skull, and long anteroposterior dimension with unerupted dentition, dentigerous cyst-like follicles, condylar defects, and gingival hyperplasia. An 18-year-old boy with Maroteaux-Lamy syndrome (mucopolysaccharidosis type VI) is described in this article, emphasizing the oral manifestations and radiographic illustration of lesions in the jaws. It also emphasizes the essential role of cone-beam computed tomography to identify and analyze multicentric pathologies in the jaws.

Effect of mitomycin-C on corneal endothelial cell parameters after refractive surface ablation procedures

Background

The effect of mitomycin-C (MMC) on the reduction of endothelial cell count in the cornea remains controversial. We aimed to evaluate the effect of MMC on corneal endothelial cell parameters after refractive surface ablation procedures, including photorefractive keratectomy (PRK) and laser epithelial keratomileusis (LASEK).

Methods

In this interventional, comparative, follow-up study, 342 eyes of 171 patients were followed up for 6 months. Patients undergoing PRK or LASEK were included and were divided into two groups: group one (188 eyes of 94 patients) with an ablation depth of ≥ 65 µm and who received intraoperative 0.02% MMC for 30 s, and group two (154 eyes of 77 patients) with an ablation depth of < 65 µm and who received balanced salt solution for 30 s. Changes in endothelial cell density (ECD), central corneal thickness (CCT), coefficient of variation (CV), and hexagonality values were compared between the groups at 3 and 6 months after surgery.

Results

The mean (standard deviaiton [SD]) age of the patients was 28.11 (6.56) years. The mean (SD) ECD did not change significantly in either group between the baseline and at 3 and 6 months postoperatively. The baseline mean ECD was significantly higher in group one than that in group two (P < 0.001) and remained so at 3 (P = 0.002) and 6 months (P = 0.022) postoperatively. The baseline hexagonality value was lower in group one (P = 0.173), with a gradual decrease during the postoperative follow-up as compared with that in group two (P = 0.016 and 0.001 at 3 and 6 months postoperatively, respectively). Group one had a significantly lower CCT at 3 and 6 months postoperatively (both P < 0.001) and a higher mean CV (3 months: P = 0.028; 6 months: P = 0.328).

Conclusions

A single intraoperative application of MMC for 30 s as prophylaxis for corneal haze development during refractive surface ablation procedures had no significant effect on ECD up to 6 months postoperatively. Future studies with a contralateral-eye design (to neutralize factors specific to the individual patient), a larger sample size, and longer follow-up are necessary to confirm or disprove our observations.

Corneal Opacity: Cell Biological Determinants of the Transition From Transparency to Transient Haze to Scarring Fibrosis, and Resolution, After Injury

Purpose

To highlight the cellular, matrix, and hydration changes associated with opacity that occurs in the corneal stroma after injury.

Methods

Review of the literature.

Results

The regulated transition of keratocytes to corneal fibroblasts and myofibroblasts, and of bone marrow-derived fibrocytes to myofibroblasts, is in large part modulated by transforming growth factor beta (TGFβ) entry into the stroma after injury to the epithelial basement membrane (EBM) and/or Descemet's membrane. The composition, stoichiometry, and organization of the stromal extracellular matrix components and water is altered by corneal fibroblast and myofibroblast production of large amounts of collagen type I and other extracellular matrix components-resulting in varying levels of stromal opacity, depending on the intensity of the healing response. Regeneration of EBM and/or Descemet's membrane, and stromal cell production of non-EBM collagen type IV, reestablishes control of TGFβ entry and activity, and triggers TGFβ-dependent myofibroblast apoptosis. Eventually, corneal fibroblasts also disappear, and repopulating keratocytes reorganize the disordered extracellular matrix to reestablish transparency.

Conclusions

Injuries to the cornea produce varying amounts of corneal opacity depending on the magnitude of cellular and molecular responses to injury. The EBM and Descemet's membrane are key regulators of stromal cellularity through their modulation of TGFβ. After injury to the cornea, depending on the severity of the insult, and possibly genetic factors, trace opacity to severe scarring fibrosis develops. Stromal cellularity, and the functions of different cell types, are the major determinants of the level of the stromal opacity.

Clinical management of a rare Peters' anomaly-induced secondary childhood glaucoma: A case report

Childhood glaucoma is a rare disorder that occurs from birth until teenage years caused by an abnormality of aqueous humor pathways. About 50-70% of Peters' anomaly is accompanied by secondary childhood glaucoma. The presence of glaucoma will affect the prognosis. We reported the evaluation and treatment of secondary childhood glaucoma due to Peters' anomaly. A 5 months-old boy was presented with the complaint of a enlarged left eye since 3 months old. The complaint was accompanied by a watering eye and frequently closed upon light exposure. The left eye looked opaquer than contralateral. Examination under anesthesia showed that the intraocular pressure (IOP) was 35 mmHg in the left eye and the corneal diameter was 14 mm. Other findings were keratopathy, diffuse corneal edema, buphthalmos, shallow anterior chamber, anterior synechiae, and linear slit shaped pupils in the nasal region. Patient was treated with ophthalmic timolol maleate which was later followed by trabeculectomy. After 1 week post-surgery, IOP assessment by palpation suggested the right eye within normal range while the IOP of left eye was higger than normal. Blepharospasm, epiphora, photophobia, bleb on superior, subconjunctiva bleeding, buphthalmos, keratopathy, minimal corneal edema, anterior chamber with shallow image, and posterior synechia were found in left eye anterior segment. In conclusion, trabeculotomy and trabeculectomy are recommended if there is no reduction of IOP observed after receiving timolol maleate therapy. The choice of surgical management is dependent on the feasibility of the protocol.

A novel pathogenic variant in LCAT causing FLD. A case report

BACKGROUND

Fish-eye disease (FED) is due to a partial deficiency in LCAT activity. Nevertheless, Familial lecithin-cholesterol acyltransferase deficiency (FLD), also called Norum disease, appears when the deficiency is complete. They are both rare genetic disorders inherited in an autosomal recessive manner. Clinical signs include decreased circulating HDL cholesterol and dense corneal opacity. Kidney injuries also affect patients suffering from FLD. The diagnosis of FLD is based on the presence of characteristic signs and symptoms and confirmed by genetic testing.

CASE PRESENTATION

We present a case of a 63-year-old man showing an altered lipid profile with low HDL cholesterol, chronic kidney disease (CKD) and corneal disorders. He was referred to genetic counseling in order to discard genetic LCAT deficiency due to decreased visual acuity caused by corneal opacity. A massive DNA sequencing was conducted using a multigene panel associated with lipid metabolism disturbances.Results and genetic findings: Two likely pathogenic variants in LCAT were identified and later confirmed by Sanger sequencing. Both (c.491 G > A and c.496 G > A) were missense variants that originated an amino acid substitution (164Arginine for Histidine and 166Alanine for Threonine, respectively) modifying the protein sequence and its 3D structure.

CONCLUSIONS

FLD and FED sharing common biochemical features, and the existence of other diseases with similar clinical profiles underline the need for a timely differential diagnosis aiming to address patients to preventive programs and future available therapies. This case, added to the reduced number of publications previously reported regarding FLD and FED, contributes to better understanding the genetic characteristics, clinical features, and diagnosis of these syndromes.

[Classification Model of Corneal Opacity Based on Digital Image Features]

OBJECTIVE

According to the digital image features of corneal opacity, a multi classification model of support vector machine (SVM) was established to explore the objective quantification method of corneal opacity.

METHODS

The cornea digital images of dead pigs were collected, part of the color features and texture features were extracted according to the previous experience, and the SVM multi classification model was established. The test results of the model were evaluated by precision, sensitivity and F1 scores. The optimal feature subset was found by SVM-RFE combined with cross validation to optimize the model.

RESULTS

In the classification of corneal opacity, the highest F1 score was 0.974 4, and the number of features in the optimal feature subset was 126.

CONCLUSIONS

The SVM multi classification model can classify the degree of corneal opacity.

Visual Outcomes in Pediatric Patients with Peters Anomaly

Purpose

This study aimed to evaluate the visual outcomes of pediatric patients diagnosed with Peters anomaly (PA) in a tertiary eye care center.

Methods

This was a retrospective study undertaken at a single academic center. Clinical records of pediatric patients diagnosed with PA from 2000 to 2017 were reviewed. Parameters recorded included visual acuity (VA), intraocular pressure (IOP), presence of glaucoma, and surgical procedures performed. The impact of PA type on final visual acuity levels was analyzed using generalized estimation equation models.

Results

Twenty-one eyes from 11 patients were analyzed. At the final visit, 9 eyes (42.8%) had a VA ≥20/200, while 12 (57%) had <20/200, ranging from 20/250 to no light perception. Of the study cohort, 15 (71.5%) eyes had type I, while six (28.5%) had type II PA. Glaucoma was present in 20 eyes (95%) at the final visit. One eye had dense central leucoma and microphthalmos where IOP could not be measured accurately. Seventeen eyes (81%) underwent at least one intraocular surgery, while the average number of surgeries per eye was 2.9 ± 2.5 (range=0– 9). The type of PA beta(se)=0.53 (0.41), p = 0.20] was not found to be a significant risk factor for worse VA.

Conclusion

Severe visual impairment develops in the majority of patients with PA. The type of anomaly does not appear to be associated with a worse visual function in patients with PA. Glaucoma develops in a high percentage of this patient population, and thus close monitoring of IOP in this patient population is crucial.

Transgenic Mice Overexpressing PG1 Display Corneal Opacity and Severe Inflammation in the Eye

Antimicrobial peptides (AMPs) are of interest as alternatives to antibiotics or immunomodulators. We generated and characterized the phenotypes of transgenic mice overexpressing protegrin 1 (PG1), a potent porcine cathelicidin. No obvious differences were observed between PG1 transgenic and wild-type mice in terms of growth, development, general behaviour, and the major immune cell population. However, PG1 transgenic mice intranasally infected with Staphylococcus aureus resulted in a reduction in microscopic pulmonary injury, improved clearance of bacteria, and lower proinflammatory cytokine secretion, compared to those of wild-type mice. On the other hand, approximately 25% of PG1 transgenic mice (n = 54/215) showed corneal opacity and developed inflammation in the eye, resulting ultimately in phthisis bulbi. Immunohistochemical analyses revealed that PG1 and its activator, neutrophil elastase, localized to the basal cells of the cornea and glands in eyelids, respectively. In addition, apoptosis indicated by a Terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL)-positive signal was detected from flat cells of the cornea. Our study suggests that the expression regulation or localization of AMPs such as PG1 is important to prevent their adverse effects. However, our results also showed that the cytotoxic effects of PG1 on cells could be tolerated in animals, except for the eyes.

A recognition survey of granular corneal dystrophy type 2 genetic detection in China

AIM

To evaluate the feasibility of promoting genetic detection for granular corneal dystrophy type 2 (GCD₂) by a questionnaire conducted among citizens in five cities in China.

METHODS

The data were collected by questionnaire, and analyzed by Chi-square test and one-tailed t test in IBM SPSS statistics.

RESULTS

Based on the survey data on the awareness of GCD₂ genetic detection in this study and the positive predictive analysis report of the citizens in five cities in China, the vast majority (84.2%) of respondents had never heard of it and did not know that GCD₂ patients have been prohibited from performing excimer surgery that can deteriorate GCD₂ patients' condition even leading to blindness. Though 3.4% of patients understood GCD₂ very much, they have no idea that GCD₂ could not be 100% accuracy diagnosed by the conventional inspection methods.

CONCLUSION

It is feasible and necessary to use GCD₂ genetic detection as an excimer preoperative examination project. In order to promote the development of detection project, a few improvements should be carried out in terms of the promoting efforts, costs, and research progress.

Fourier-domain optical coherence tomography-guided phototherapeutic keratectomy for the treatment of anterior corneal scarring

AIM

To evaluate the safety, visual and anatomic outcomes of fourier-domain optical coherence tomography (FD-OCT)-guided excimer laser phototherapeutic keratectomy (PTK) combined with photorefractive keratectomy (PRK) surgery in treating anterior corneal scarring.

METHODS

Clinical data of 23 eyes of 21 patients with anterior corneal scarring underwent FD-OCT-guided PTK and PRK from Dec. 2014 to Jul. 2016 were reviewed. Patients were assessed for preoperative and postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), contrast sensitivity (CS), FD-OCT, corneal topography and colour figures of anterior segments.

RESULTS

The preoperative corneal pathologic conditions included viral keratitis (7 patients, 7 eyes), band keratopathy (2 patients, 4 eyes), corneal dystrophy (4 patients, 4 eyes), traumatic corneal disease (2 patients, 2 eyes) and corneal chemical injury (6 patients, 6 eyes). Mean follow-up time was 10.65 (range, 3-19)mo. UCVA (in logMAR) improved from a mean of 0.79 (95%CI, 0.28-1.29) preoperatively to a mean of 0.45 (95%CI, 0.29-0.62) postoperatively (P=0.021). BSCVA (in logMAR) improved from 0.57 (95%CI, 0.27-0.88) preoperatively to a mean of 0.28 (95%CI, 0.15-0.41) postoperatively (P=0.001). Corneal topographic indices postoperatively showed significant improvement in corneal cylinder (P=0.009), the surface regularity index (P=0.007) and surface asymmetry index (P=0.00). Postoperative spherical equivalent averaged -0.53 diopters (-1.49 to 0.42). No complications were associated with the treatment.

CONCLUSION

FD-OCT-guided PTK combined with PRK is safe and effective for the treatment of anterior corneal scarring by eliminating or reducing corneal opacities.

Three-year follow-up in advanced pediatric keratoconus: thin corneas may not have pachymetry properly assessed after crosslinking

AIM

To analyze the crosslinking (CXL) effects in pediatric keratoconus, and to identify the patients' corneal characteristics whose pachymetry could not be adequately evaluated by Scheimpflug method after procedure.

METHODS

Consecutive pediatric patients with progressive keratoconus underwent CXL were included. Best-corrected visual acuity (BCVA) and spheric equivalent (SE) were measured before and after CXL. After CXL, groups 1 and 2 were divided based on the posterior surface Pentacam quality specifications (QS): "OK" (Group 1) and "not OK" (Group 2). The mean (RmF and RmB) and minimum (RminF and RminB) radius of curvatures of the anterior and posterior corneal surfaces, and the thinnest pachymetry (Pmin) were measured preoperatively at 3, 6, 12, 24, and 36mo. Haze was annotated.

RESULTS

Twenty-six patients (14 men, mean age 14±1.8y) and median Kmax of 59.9 D initially and 61.4 D preoperatively were treated. BCVA was not different before and 24mo after CXL. Group 2 statistically differed to group 1 in that SE was more myopic before and with no difference 24mo after CXL; RmF and RmB were steeper and Pmin was thinner pre-surgically. Group 2, in which pachymetric changes could not be adequately evaluated after surgery, presented with significant RmF flattening, a shift to hyperopia, and more haze after CXL.

CONCLUSION

Patients whose pachymetry could not be adequately evaluated after CXL had steeper and thinner corneas before surgery. The predictive factors for impaired QS after CXL are RmF, RmB, and Pmin. In advanced keratoconus, alternative methods to analyze pachymetry and the posterior surface should be considered.

Corneal sterile infiltration induced by topical use of ocular hypotensive agent

PURPOSE

To report two cases with corneal sterile infiltration presumably due to topical ocular hypotensive agent.

METHOD

Case report.

RESULTS

Case 1: A 65-year-old man presented with corneal opacity and neovascularization in his left eye. A diagnosis of glaucoma was made 2 years previously, and anti-glaucoma agents were prescribed (brimonidine tartrate, ripasudil hydrochloride hydrate, and brinzolamide) for both eyes. Case 2: A 75-year-old woman noticed corneal opacity in the left eye. A diagnosis of glaucoma was made 35 years previously, and anti-glaucoma agents were prescribed (brimonidine tartrate, 1% dorzolamide, and bimatoprost) for both eyes. In both cases, ocular examination revealed follicular conjunctivitis and blepharitis in both eyes, and corneal sterile infiltration with neovascularization in the left eyes. The three topical drugs were discontinued and replaced with 0.1% fluorometholone. Both the blepharitis and corneal sterile infiltration improved thereafter, although corneal opacity remained across the stromal layer.

CONCLUSION

We encountered two cases of corneal and conjunctival complications that were suspected as side effects after brimonidine eye drop use. Special care should be taken to observe the condition of ocular surface when topical brimonidine is administered.

Loss of Down Syndrome Critical Region-1 Mediated-Hypercholesterolemia Accelerates Corneal Opacity Via Pathological Neovessel Formation

OBJECTIVE

The calcineurin-NFAT (nuclear factor for activated T cells)-DSCR (Down syndrome critical region)-1 pathway plays a crucial role as the downstream effector of VEGF (vascular endothelial growth factor)-mediated tumor angiogenesis in endothelial cells. A role for DSCR-1 in different organ microenvironment such as the cornea and its role in ocular diseases is not well understood. Corneal changes can be indicators of various disease states and are easily detected through ocular examinations. Approach and Results: The presentation of a corneal arcus or a corneal opacity due to lipid deposition in the cornea often indicates hyperlipidemia and in most cases, hypercholesterolemia. Although the loss of Apo (apolipoprotein) E has been well characterized and is known to lead to elevated serum cholesterol levels, there are few corneal changes observed in ApoE^-/- mice. In this study, we show that the combined loss of ApoE and DSCR-1 leads to a dramatic increase in serum cholesterol levels and severe corneal opacity with complete penetrance. The cornea is normally maintained in an avascular state; however, loss of Dscr-1 is sufficient to induce hyper-inflammatory and -oxidative condition, increased corneal neovascularization, and lymphangiogenesis. Furthermore, immunohistological analysis and genome-wide screening revealed that loss of Dscr-1 in mice triggers increased immune cell infiltration and upregulation of SDF (stromal derived factor)-1 and its receptor, CXCR4 (C-X-C motif chemokine ligand receptor-4), potentiating this signaling axis in the cornea, thereby contributing to pathological corneal angiogenesis and opacity.

CONCLUSIONS

This study is the first demonstration of the critical role for the endogenous inhibitor of calcineurin, DSCR-1, and pathological corneal angiogenesis in hypercholesterolemia induced corneal opacity.

Progressive eye pathology in mucopolysaccharidosis type I mice and effects of enzyme replacement therapy

BACKGROUND

Mucopolysaccharidosis type I (MPS I) is a lysosomal storage disorder caused by α-L-iduronidase deficiency, resulting in accumulation of glycosaminoglycans (GAG). Ophthalmological manifestations are common in MPS I patients and often lead to visual impairment. Accumulation of GAG in corneal or retinal tissues reduces vision causing corneal opacity and neurosensory complications. One available treatment for MPS I patients is enzyme replacement therapy (ERT), but the results of such treatment on eye disease are still debatable. Therefore, we aimed to determine the progression of ocular manifestations as well as the effectiveness of intravenous ERT in MPS I.

METHODS

Corneal and retinal analyses were perform in eyes from 2- to 8-month normal and MPS I mice. Some MPS I mice received ERT (1.2 mg/kg of laronidase) every 2 weeks from 6 to 8 months and histological findings were compared with controls. Additionally, cornea from two MPS I patients under ERT were evaluated.

RESULTS

Mouse corneal tissues had GAG accumulation early in life. In the retina, we found a progressive loss of photoreceptor cells, starting at 6 months. ERT did not improve or stabilize the histological abnormalities. MPS I patients, despite being on ERT for over a decade, presented GAG accumulation in the cornea, corneal thickening, visual loss and needed corneal transplantation.

CONCLUSION

We provide data on the time course of ocular alteration in MPS I mice. Our results also suggest that ERT is not effective in treating the progressive ocular manifestations in MPS I mice and fails to prevent corneal abnormalities in patients.

Effect of diluted povidone iodine in adenoviral keratoconjunctivitis on the rate of subepithelial corneal infiltrates

AIM

To evaluate the clinical characteristics of adenoviral keratoconjunctivitis, the management modalities, as well as the incidence of subepithelial corneal infiltrates (SEI).

METHODS

Patients with characteristic clinical symptoms and signs, who presented to our clinic within the first week of symptoms and received the diagnosis of adenoviral keratoconjunctivitis between January 2013 and April 2016, were included in the study. A total of 211 patients were included in the study. Patients were evaluated for the incidence of clinical signs, late complications, management preferences, and the effect of diluted povidone-iodine (d-PVP-I) 2%.

RESULTS

Patients' mean age was 33.03±14.76y. We observed an increase in the number of cases according to the years. At presentation and/or early follow-up, the clinical signs were conjunctival hyperemia (100%), conjunctival follicules (79.1%), edema of the eyelids (39.3%), chemosis (16.1%), pseudomembrane formation (16.6%), and corneal epitheliopathy (29.9%). During late follow-up 13.3% patients developed conjunctival subepithelial fibrosis, and 39.8% developed SEI. A significant decrease in the incidence of SEI development was observed in patients who used d-PVP-I 2% (P=0.032; 33.3% vs 45.9%, respectively in patients who received d-PVP-I 2% and who did not).

CONCLUSION

Adenoviral keratoconjunctivitis has a tremendous effect on patient's comfort and abilities in short-term. Additionally, almost half of the patients develop visual problems related to SEI. According to our clinical experience, using d-PVP-I 2% in the first days of adenoviral keratoconjunctivitis might be helpful in reducing the risk of SEI as a complication.

Phacoemulsification in eyes with corneal opacities after deep anterior lamellar keratoplasty

To evaluate the maneuverability and efficacy of phacoemulsification and intraocular lens (IOL) implantation in eyes with corneal opacities after deep anterior lamellar keratoplasty (DALK), twelve eyes of 12 patients with mild to moderate corneal opacities after DALK and coexisting cataracts were analyzed retrospectively. Phacoemulsification and IOL implantation assisted with anterior capsule staining, as well as non-invasive optical fiber illumination, were performed on all eyes. No intraoperative or postoperative complications were noted. Mean corrected distance visual acuity (logMAR) improved from 1.24±0.17 to 0.73±0.22. Post-phaco intraocular pressure was maintained between 13 to 20 mm Hg in all cases throughout the follow-up period. Mean endothelial cell density decreased from 2258.42±205.94 to 1906.25±174.23 cells/mm². Phacoemulsification and IOL implantation are safe and valid in eyes with mild to moderate corneal opacities after DALK and coexisting cataracts when assisted with anterior capsule staining and non-invasive optical fiber illumination.

Ophthalmologic manifestations in Taiwanese patients with mucopolysaccharidoses

Background

Mucopolysaccharidoses (MPSs) are a group of rare lysosomal storage disorders characterized by the accumulation of glycosaminoglycans in various tissues and organs. Ocular problems that affect the cornea, trabecular meshwork, sclera, retina, and optic nerve are very common in these patients. However, there was limited literature focusing on comprehensive ocular findings in different types of MPS.

Methods

We retrospectively reviewed the clinical ophthalmologic features and electrodiagnostic results of 50 Taiwanese patients with a diagnosis of MPS (34 males and 16 females; age range, 1.1–34.9 years; nine with MPS I, 17 with MPS II, 17 with MPS IV, and seven with MPS VI).

Results

Among 44 patients with available data for visual acuity, 15 patients (34%) had a visual acuity of less than 0.5 (6/12) equivalent in their better eye, including 71% of those with MPS VI, 38% with MPS IV, 29% with MPS I, and 14% with MPS II. Severe corneal opacities existed in 57% of MPS VI patients and 11% of MPS I patients, compared with none for MPS II and MPS IV patients. Among 80 eyes with available data of refraction, 11 eyes (14%) had myopia (≦−0.50 D), 55 eyes (69%) had hyperopia (≧0.50 D), and 55 eyes (69%) had high astigmatism (≧1.50 D). Ocular hypertension was found in 45% (28/62) of eyes. There were 16% (14/90), 11% (10/90), 13% (12/90), 31% (27/86), and 79% (30/38) of MPS eyes with lens opacities, optic disc swelling, optic disc cupped, retinopathy, and visual pathway dysfunction, respectively. Intraocular pressure was positively correlated with the severity of corneal opacity (p < 0.01).

Conclusions

Ocular complications with significant reduction in visual acuity are common in MPS patients. Diagnostic problems may arise in these patients with severe corneal opacification, especially for those with MPS VI and MPS I.

[Temporal pattern of postmortem color changes in the pupil region of the cornea in rabbits]

OBJECTIVE

To explore the temporal pattern of postmortem color changes in the pupil region of the cornea for noninvasive estimation of the postmortem interval (PMI).

METHODS

Two rabbit models of air embolism and drowning were established in a dark room at a temperature of 20 ℃ with a relative humidity of 30%. The corneal images of the rabbits were acquired using a digital camera at two-hour intervals within 72 h after death. The pupil region on the corneal images was segmented using computer image processing technique (MATLAB), and the parameters of 6 image color features (RGBHSV) were extracted. Regression analysis was used to analyze the relationship between these parameters and the PMI, and the effects of different death causes on the changes of the corneal color features were also assessed.

RESULTS

Within 72 h after death from different causes, the R, G and B values of the pupil region on the corneal images all tended to increase with the PMI, showing a good fitting with the PMI (P &lt; 0.01). No significant correlation was found between the values of H, S and V and the PMI (P&gt;0.05). The R, G and B values in the pupil region on the corneal images showed consistent variation trends after death from the two causes, and their correlations with PMI were also similar. The measured values of R, G and B in air embolism group were greater than those in the drowning group.

CONCLUSIONS

The postmortem color changes of the pupil region on corneal images follow an identifiable temporal pattern and can vary across different causes of death. The regression equations established in this study provide references for non-invasive and objective estimation of the PMI.

Tropical Keratopathy (Florida Spots) in Cats

The authors used microscopy and synchrotron-based small-angle X-ray scattering analysis (SAXS) to describe lesions macroscopically typical of tropical keratopathy ("Florida spots") from 6 cats on St Kitts. Microscopically, there were varying degrees of epithelial hyperplasia and thinning of the cornea (by 4% to 18%) due to loss of corneal stroma associated with dense accumulations of collagen in the superficial stroma. The collagen fibrils in lesions were wider and had more variable diameters (39.5 ± 5.0 nm, mean ± SD) than in normal corneas (25.9 ± 3.6 nm; P < .01). There were occasional vacuoles (<1 μm) in the corneal epithelial basement membrane but no evidence of inflammation, edema, stromal neovascularization, fibrosis, acid-fast organisms, or structures suggestive of a fungal organism. SAXS analysis showed collagen fibril diameters and variation in size were greater in stroma containing the lesions compared to normal corneas (48.8 ± 4.5 nm vs 35.5 ± 2.6; P < .05). The d-spacing of collagen in the stroma of lesions and normal corneas was the same, but the average orientation index of collagen in lesions was greater (0.428 ± 0.08 vs 0.285 ± 0.03; P < .05). A survey revealed Florida spots lesions were static over time and became less obvious in only 1 of 6 affected cats adopted on St Kitts and taken to areas in the US where lesions are not reported. An anterior stromal collagen disorder with various degrees of epithelial hyperplasia is the pathologic hallmark of lesions clinically identical to Florida spots in cats from St Kitts.

Twenty five-gauge endoscopic vitrectomy for proliferative vitreoretinopathy with severe corneal opacity

PURPOSE

To report 4 cases undergoing 25-gauge endoscopic vitrectomy for the treatment of proliferative vitreoretinopathy with severe corneal opacity in which a transpupillary view of the fundus was not possible.

STUDY DESIGN

A retrospective interventional case series.

METHODS

The main outcomes measured were postoperative anatomic status of the retina and subjective improvement of vision.

RESULTS

Postoperative reattachment of the retina and subjective improvement of vision were achieved in all 4 eyes.

CONCLUSION

Twenty five-gauge endoscopic vitrectomy provides a clear view making it possible conduct pars plana vitrectomy in order to reattach the retina in cases of proliferative vitreoretinopathy with severe corneal opacity.

Stings of the Ant Wasmannia auropunctata (Hymenoptera: Formicidae) as Cause of Punctate Corneal Lesions in Humans and Other Animals

Numerous researchers have observed a form of punctate corneal lesions causing leukomas (corneal opacities) in humans, domestic animals, and wild animals in different parts of the world. This condition has been reported under different names, including West Indian (or Caribbean) punctate keratopathy, West Indian dots, tropical punctate keratopathy, Rice's keratopathy, Florida keratopathy, and Florida spots. Many of these cases, appear to have a common cause, the stings of a small red ant, Wasmannia auropunctata (Hymenoptera: Formicidae), originally from the Neotropics, but spread to other parts of the world through human commerce. The purpose of this article is to link disparate literature on punctate or nummular corneal lesions published in medical, veterinary, wildlife, and entomology journals, because many researchers seem largely unaware of the literature from disciplines other than their own. Recognizing a common cause of this corneal condition is important to insure proper medical treatment and foster efforts to limit the spread and negative impact of W. auropunctata.

Clinical progression of ocular injury following arsenical vesicant lewisite exposure

Ocular injury by lewisite (LEW), a potential chemical warfare and terrorist agent, results in edema of eyelids, inflammation, massive corneal necrosis and blindness. To enable screening of effective therapeutics to treat ocular injury from LEW, useful clinically-relevant endpoints are essential. Hence, we designed an efficient exposure system capable of exposing up to six New-Zealand white rabbits at one time, and assessed LEW vapor-induced progression of clinical ocular lesions mainly in the cornea. The right eye of each rabbit was exposed to LEW (0.2 mg/L) vapor for 2.5, 5.0, 7.5 and 10.0 min and clinical progression of injury was observed for 28 days post-exposure (dose-response study), or exposed to same LEW dose for 2.5 and 7.5 min and clinical progression of injury was observed for up to 56 days post-exposure (time-response study); left eye served as an unexposed control. Increasing LEW exposure caused corneal opacity within 6 h post-exposure, which increased up to 3 days, slightly reduced thereafter till 3 weeks, and again increased thereafter. LEW-induced corneal ulceration peaked at 1 day post-exposure and its increase thereafter was observed in phases. LEW exposure induced neovascularization starting at 7 days which peaked at 22-35 days post-exposure, and remained persistent thereafter. In addition, LEW exposure caused corneal thickness, iris redness, and redness and swelling of the conjunctiva. Together, these findings provide clinical sequelae of ocular injury following LEW exposure and for the first time establish clinically-relevant quantitative endpoints, to enable the further identification of histopathological and molecular events involved in LEW-induced ocular injury.

Persistent gross lipemia and suspected corneal lipidosis following intravenous lipid therapy in a cat with permethrin toxicosis

OBJECTIVE

To describe the observation of persistent gross lipemia and suspected corneal lipidosis following intravenous lipid therapy (IVLT) in a cat with permethrin toxicosis.

CASE SUMMARY

A 5-year-old, spayed female, domestic short-haired cat with permethrin toxicosis was treated with a high dose of IVLT as an adjunct treatment when it remained severely obtunded following traditional supportive care. The cat received intravenous 20% lipid emulsion as a 1.5 mL/kg bolus given over 10 minutes followed by a constant rate infusion of 0.25 mL/kg/min for 2 hours. The cat developed gross lipemia that persisted at least 48 hours after the single dose of IVLT. Changes consistent with corneal lipidosis were observed and resolved within 1 week after IVLT.

NEW OR UNIQUE INFORMATION PROVIDED

This is the first report documenting the complications of persistent gross lipemia and suspected corneal lipidosis in a cat following IVLT. This report underscores the off-label, experimental nature of IVLT as a treatment for intoxication in cats.

Preliminary results of a prospective study of inter- and intra-user variability of the Royal Veterinary College corneal clarity score (RVC-CCS) for use in veterinary practice

OBJECTIVE

To introduce a new corneal clarity score for use in small animals and describe its inter- and intra-user variability.

ANIMALS STUDIED

Twelve dogs and two cats with corneal abnormalities and five dogs with healthy corneas.

MATERIALS AND METHODS

Four examiners scored every patient twice and never consecutively, focusing on the central cornea. The peripheral cornea was scored separately. The following scoring system was used to describe corneal clarity: G0: no fundus reflection is visible on retroillumination (RI) using a head-mounted indirect ophthalmoscope. G1: a fundus reflection is visible with RI. G2: a 0.1-mm diameter light beam is visible on the anterior surface of the iris and/or lens. G3: gross fundic features are visible when viewed with indirect ophthalmoscopy (IO) using a head-mounted indirect ophthalmoscope and a hand-held 30D lens, although fine details are not clear. G4: fine details of the fundic features are clearly visible with IO. The minimum grades given were analyzed for inter- and intra-user variability with kappa analysis.

RESULTS

Intra- and interuser variability of the central corneal clarity ranged from 0.78 to 0.96, showing substantial to almost perfect reproducibility, and from 0.66 to 0.91, showing substantial to almost perfect reliability, respectively. Intra- and interuser variability of the peripheral cornea ranged from 0.83 to 0.95, showing almost perfect agreement, and from 0.53 to 0.91, showing moderate to almost perfect agreement.

CONCLUSIONS

The RVC-CCS is well suited to assess and monitor central corneal clarity in small animals and to compare outcomes between studies and different surgeons.

Corneal Opacity in Domestic Ducks Experimentally Infected With H5N1 Highly Pathogenic Avian Influenza Virus

Domestic ducks can be a key factor in the regional spread of H5N1 highly pathogenic avian influenza (HPAI) virus in Asia. The authors performed experimental infections to examine the relationship between corneal opacity and H5N1 HPAI virus infection in domestic ducks (Anas platyrhyncha var domestica). A total of 99 domestic ducks, including 3 control birds, were used in the study. In experiment 1, when domestic ducks were inoculated intranasally with 2 H5N1 HPAI viruses, corneal opacity appeared more frequently than neurologic signs and mortality. Corneal ulceration and exophthalmos were rare findings. Histopathologic examinations of the eyes of domestic ducks in experiment 2 revealed that corneal opacity was due to the loss of corneal endothelial cells and subsequent keratitis with edema. Influenza viral antigen was detected in corneal endothelial cells and some other ocular cells by immunohistochemistry. Results suggest that corneal opacity is a characteristic and frequent finding in domestic ducks infected with the H5N1 HPAI virus. Confirming this ocular change may improve the detection rate of infected domestic ducks in the field.

Ophthalmic diseases and disorders in free-ranging rhesus macaque (Macaca mulatta) of Shivalik hill area of Himachal Pradesh, Northern India

BACKGROUND

The studies on ophthalmic diseases and disorders in a population of rhesus macaques, in particular with free-ranging macaques, are limited mainly by the difficulty in capturing animals and obtaining samples.

METHODS

From October 2011 to 2013, prevalence of various ophthalmic affections was recorded and analyzed on the basis of sex, age-group, and disease condition both in urban and peri-urban free-ranging rhesus macaques (Macaca mulatta) from various locations in Shivalik hill areas of Himachal Pradesh in northern India, as a part of clinical health examination.

RESULTS AND CONCLUSION

Ophthalmic diseases were more prevalent in macaques captured from urban settings than those from peri-urban, and difference between two groups was statistically significant (P < 0.01). Further classification of ophthalmic diseases revealed that traumatic injuries, corneal opacity, and cataract were significantly higher in urban than those in peri-urban macaque (P < 0.01). Similarly, the ophthalmic disorders among different age-groups were also found statistically significant (P < 0.01). The effect of sex on ophthalmic disorders was not found significant. Overviewing these results, disturbances in environment, close proximity to humans, and increasing age may lead to ophthalmic occurrences in these free-range macaques.

Predicting transepithelial phototherapeutic keratectomy outcomes using Fourier domain optical coherence tomography

PURPOSE

The aim of this study was to use Fourier domain optical coherence tomography to predict transepithelial phototherapeutic keratectomy outcomes.

METHODS

This is a prospective case series. Subjects with anterior stromal corneal opacities underwent an excimer laser phototherapeutic keratectomy (PTK) combined with a photorefractive keratectomy using the VISX S4 excimer laser (AMO, Inc, Santa Ana, CA). Preoperative and postoperative Fourier domain optical coherence tomography images were used to develop a simulation algorithm to predict treatment outcomes. Main outcome measures included preoperative and postoperative uncorrected distance visual acuities and corrected distance visual acuity.

RESULTS

Nine eyes of 8 patients were treated. The nominal ablation depth was 75 to 177 μm centrally and 62 to 185 μm peripherally. Measured PTK ablation depths were 20% higher centrally and 26% higher peripherally, compared with those for laser settings. Postoperatively, the mean uncorrected distance visual acuity was 20/41 (range, 20/25-20/80) compared with 20/103 (range, 20/60-20/400) preoperatively. The mean corrected distance visual acuity was 20/29 (range, 20/15-20/60) compared with 20/45 (range, 20/30-20/80) preoperatively. The MRSE was +1.38 ± 2.37 diopters (D) compared with -2.59 ± 2.83 D (mean ± SD). The mean astigmatism magnitude was 1.14 ± 0.83 D compared with 1.40 ± 1.18 D preoperatively. Postoperative MRSE correlated strongly with ablation settings, central and peripheral epithelial thickness (r = 0.99, P < 0.00001). Central islands remained difficult to predict and limited visual outcomes in some cases.

CONCLUSIONS

Optical coherence tomography measurements of opacity depth and 3-dimensional ablation simulation provide valuable guidance in PTK planning. Post-PTK refraction may be predicted with a regression formula that uses epithelial thickness measurements obtained by optical coherence tomography. The laser ablation rates described in this study apply only to the VISX laser.

Mouse strain variation in SMA(+) myofibroblast development after corneal injury

The purpose of present study was to investigate differences in myofibroblast development after haze-generating injury in different commonly used strains of mice. The inbred mouse strains used in this study were Balb/c, C57BL/6, C3H/HeJ and DBA/1J. All mice had uniform irregular phototherapeutic keratectomy with an excimer laser according to a previously published method to generate stromal haze. DBA/1J mice generated significantly greater density of alpha smooth muscle actin (SMA)-positive myofibroblasts in the anterior stroma compared to Balb/c (p < 0.05), C57BL/6 (p < 0.05) and C3H/HeJ (p < 0.01) mice. The C3H/HeJ strain had significantly lower density of SMA-positive myofibroblasts compared to other three mouse strains. These results indicate that mouse strain must be considered in designing experiments and interpreting the results of experiments in which corneal haze and myofibroblast generation is studied in mice. Further investigation of genetics underlying mouse strain variation could provide insight into the corneal wound healing and haze generation processes.

TGFBI gene mutation analysis in a Chinese pedigree of Avellino corneal dystrophy

AIM

To analyze phenotype and genotype of a Chinese pedigree with Avellino corneal dystrophy (ACD).

METHODS

Complete ophthalmic examinations were performed on all the family members. Exons of TGFBI were amplified by polymerase chain reaction, sequenced, and compared with a reference database.

RESULTS

A single heterozygous G>A (R124H) point mutation was identified in exon 4 of TGFBI in three affected members and two unaffected children who were offsprings of the affected members, but not in the other family members.

CONCLUSION

Mutation R124H in TGFBI was identified in this pedigree and appeared to be the disease causing mutation. Atypical phenotype and low penetrance was observed in this pedigree.

Sclerocornea associated with the chromosome 22q11.2 deletion syndrome

Reported ocular findings in the 22q11.2 deletion syndrome (which encompasses the phenotypes of DiGeorge, velocardiofacial, and Takao (conotruncal-anomaly-face) syndromes) have included posterior embryotoxon (prominent, anteriorly displaced Schwalbe's line at the corneal limbus or edge), retinal vascular tortuosity, eyelid hooding, strabismus, and astigmatism. We present seven 22q11.2 patients from multiple centers with sclerocornea, an eye finding previously unreported in the literature. Four boys and three girls were identified with sclerocornea, systemic DGS/VCFS findings, and fluorescence in situ hybridization (FISH)-confirmed microdeletion at chromosome 22q11.2. FISH diagnosis was perinatal in six patients but at 2 years of age in one child. Sclerocornea was bilateral in five patients. Findings included descemetocele (five eyes), microophthalmos (one eye), iridocorneal adhesions (one bilateral case), and severe anterior segment dysgenesis (one eye). Two patients underwent bilateral corneal transplantation; another two were scheduled for possible unilateral transplant. Sclerocornea is a static congenital condition in which the cornea is opaque and vascularized and resembles the sclera. The novel finding of sclerocornea suggests that a genetic locus at 22q11.2 may be involved in anterior segment embryogenesis. In most of our patients, the diagnostic process was underway, but in one patient 22q11.2 deletion was not suspected until after the child had already been undergoing treatment for sclerocornea for 2 years. Sclerocornea should be added to the clinical manifestations of the 22q11.2 deletion syndrome. Ophthalmologists diagnosing sclerocornea in children with systemic findings suggestive of 22q11.2 deletion should ensure appropriate genetic referral.

Causes of childhood blindness in the northeastern states of India

BACKGROUND

The northeastern region (NER) of India is geographically isolated and ethno-culturally different from the rest of the country. There is lacuna regarding the data on causes of blindness and severe visual impairment in children from this region.

AIM

To determine the causes of severe visual impairment and blindness amongst children from schools for the blind in the four states of NER of India.

DESIGN AND SETTING

Survey of children attending special education schools for the blind in the NER.

MATERIALS AND METHODS

Blind and severely visually impaired children (best corrected visual acuity < 20/200 in the better eye, aged up to 16 years) underwent visual acuity estimation, external ocular examination, retinoscopy and fundoscopy. Refraction and low vision workup was done where indicated. World Health Organization's reporting form was used to code anatomical and etiological causes of visual loss.

STATISTICAL ANALYSIS

Microsoft Excel Windows software with SPSS.

RESULTS

A total of 376 students were examined of whom 258 fulfilled the eligibility criteria. The major anatomical causes of visual loss amongst the 258 were congenital anomalies (anophthalmos, microphthalmos) 93 (36.1%); corneal conditions (scarring, vitamin A deficiency) 94 (36.7%); cataract or aphakia 28 (10.9%), retinal disorders 15 (5.8%) and optic atrophy 14 (5.3%). Nearly half of the children were blind from conditions which were either preventable or treatable (48.5%).

CONCLUSION

Nearly half the childhood blindness in the NER states of India is avoidable and Vitamin A deficiency forms an important component unlike other Indian states. More research and multisectorial effort is needed to tackle congenital anomalies.

Anterior segment dysgenesis in a child with factor VII deficiency

PURPOSE

To describe the first case of anterior segment dysgenesis associated with factor VII congenital deficit (hypoproconvertinemia).

METHOD

A 2-month-old child with factor VII deficiency was referred to our clinic because of corneal opacities. The child was born to consanguineous parents and severe factor VII deficiency was diagnosed on the third day of life because of gastrointestinal bleeding.

RESULT

Ocular examination under anesthesia showed bilateral corneal opacities with adherent iris strands and peripheral anterior synechiae. The intra-ocular pressure was normal in both eyes and there were neither signs of cataracts nor glaucomatous optic nerve damage.

CONCLUSION

This observation provide new information on the possible ocular findings in patients with hypoproconvertinemia. Based on this report, we suggest that careful coagulation screening should be considered in children who possess idiopathic anterior segment dysgenesis aiming at identifying the possible coagulation disorder.