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Congenital aniridia is a rare eye disease characterized by loss of PAX6 protein leading to aniridia-associated keratopathy that significantly reduces vision. The miR-204-5p is a possible regulator of PAX6 function and here we evaluate its effect in multiple in vitro and in vivo models. In vitro, miR-204-5p overexpression suppressed vascular factor ANGPT1 in human limbal stem cells (T-LSC) and Pax6-knockdown LSC (mut-LSC), and in primary human limbal epithelial cells (LEC) at the gene and protein levels and following LPS stimulation. However, miR-204-5p inhibited VEGFA expression only in mut-LSCs and LPS-stimulated LEC. Also, miR-204-5p increased PAX6 expression in mut-LSC and differentiated corneal epithelial cells, but not in LEC. Topical miR-204-5p after LPS-induced keratitis in mice failed to suppress Vegfa, Angpt1, Il-1β, and Tnf-α or rescue Pax6 levels in contrast to in vitro results, although it significantly reduced the inflammatory infiltrate in the cornea. In Pax6 Sey/+ aniridia mice, miR-204-5p did not rescue PAX6 levels or suppress Vegfa, Angpt1, or inhibit the ERK1/2 pathway. While short-term miR-204-5p treatment effectively suppresses VEGFA and ANGPT1 and enhances PAX6 expression in multiple corneal epithelia, effects are variable across primary and immortalized cells. Effects of longer-term in vivo treatment, however, require further study., (© 2024. The Author(s).)

Objective of Surgery: The aim of this surgical technique is the implantation of a glaucoma drainage device (GDD) in eyes with aphakic glaucoma following injector-assisted implantation of an artificial iris into the ciliary sulcus., Indications: This atraumatic tube insertion technique can be performed during GDD implantation after implantation of an artificial iris into the ciliary sulcus., Surgical Technique: Following injector-assisted implantation of an artificial iris into the ciliary sulcus of eyes, the iris can shift into the chamber angle. The GDD should be positioned in the quadrant in which the iridectomy is located. Otherwise, GDD implantation is not possible due to the resistance of the artificial iris. Alternatively, the artificial iris can be easily and non-traumatically rotated in the ciliary sulcus by flushing the anterior chamber with balanced salt solution (BSS) to move the iridectomy into the desired area and position the GDD tube in the anterior chamber. A surgical video, which is available online, shows the surgical technique in detail., Follow-Up: After GDD, dexamethasone eye drops should be applied 8 times daily for 1 week tapering down by 1 drop per week thereafter. Antibiotic eye drops, e.g., ofloxacin eye drops, are prescribed 4 times daily for 1 week and might be discontinued thereafter., Evidence: To date, this is the first description of a rotation of an artificial iris located in the ciliary sulcus by irrigation of the anterior chamber during GDD implantation., (© 2024. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Aniridia-associated keratopathy originates from a haploinsufficiency of the transcription factor PAX6 (PAX6 +/- ). In the corneal epithelium of PAX6 +/- mice, a significant increase in oxidized proteins was observed, accompanied by impaired compensation for elevated oxidative stress (OS). The extent to which limbal fibroblast cells (LFCs) are affected by an increased susceptibility to OS in cases of congenital aniridia (AN) has not been determined, yet. Our aim was to examine the impact of OS on antioxidant enzyme expression in normal and AN-LFCs. Following isolation and culture of primary LFCs (n = 8) and AN-LFCs (n = 8), cells were treated with cobalt chloride for 48 h to chemically induce hypoxic conditions and OS. Subsequently, HIF-1α/-2α, PHD1/2, Nrf2, CAT, SOD1, PRDX6, and GPX1 gene expression was examined by qPCR. SOD1, PRDX6, and GPX1 protein levels were assessed from the cell lysate by Western blot. The induction of hypoxia led to reduced HIF-1α gene expression in both fibroblast groups (p≤0.008), while the decrease in PHD1 was limited to AN-LFCs (p = 0.0007). On the other hand, under hypoxic conditions, PHD2 showed higher mRNA expression in AN-LFCs compared to normal LFCs (p = 0.013). As a result of OS, the mRNA levels of Nrf2 (p<0.0001) and the antioxidant enzymes CAT (p = 0.005), SOD1 (p = 0.005), GPX1 (p = 0.002) decreased in AN-LFCs. This was accompanied by an increased protein expression of SOD1 (p = 0.019) and PRDX6 (p=0.0009). In the normal LFC group, the induced extent of OS had no impact on the gene (p≥0.151) and protein expression (p ≥ 0.629) of antioxidant enzymes, except for the GPX1 mRNA level (p = 0.027). AN-LFCs exhibit higher susceptibility to OS than normal LFCs. Therefore, in AN-LFCs, there are sustained alterations in gene and protein expression of antioxidative enzymes even after 48 h of CoCl 2 treatment., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Development of the anterior segment of the eye requires reciprocal sequential interactions between the arising tissues, facilitated by numerous genetic factors. Disruption of any of these processes results in congenital anomalies in the affected tissue(s) leading to anterior segment disorders (ASD) including aniridia, Axenfeld-Rieger anomaly, congenital corneal opacities (Peters anomaly, cornea plana, congenital primary aphakia), and primary congenital glaucoma. Current understanding of the genetic factors involved in ASD remains incomplete, with approximately 50% overall receiving a genetic diagnosis. While some genes are strongly associated with a specific clinical diagnosis, the majority of known factors are linked with highly variable phenotypic presentations, with pathogenic variants in FOXC1, CYP1B1, and PITX2 associated with the broadest spectrum of ASD conditions. This review discusses typical clinical presentations including associated systemic features of various forms of ASD; the latest functional data and genotype-phenotype correlations related to 25 ASD factors including newly identified genes; promising novel candidates; and current and emerging treatments for these complex conditions. Recent developments of interest in the genetics of ASD include identification of phenotypic expansions for several factors, discovery of multiple modes of inheritance for some genes, and novel mechanisms including a growing number of non-coding variants and alleles affecting specific domains/residues and requiring further studies., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: A modified surgical technique of sutured scleral fixated intraocular lens (SSF-IOL) was applied in a patient with post-traumatic aniridia and aphakia., Case Presentation: A 51-year-old man was referred to our clinic with decreased vision (finger count) in his right eye. This patient had previously undergone primary repair of the ruptured globe and pars plana vitrectomy to manage ocular trauma in the same eye. On presentation, the best corrected visual acuity in his right eye was 20/40. The slit lamp examination of his right eye revealed loss of total iris and lens. Corneal endothelial cell density was 1462 cells/mm 2 . Fundoscopic examination of the right eye revealed a retinal attachment. For IOL implantation, a rigid poly methyl methacrylate IOL was used with a 2-point scleral fixation performed using a polypropylene suture. One year postoperatively, the uncorrected distance visual acuity was 20/32, and the manifest refraction was - 0.5/-1.5 × 130 (20/20). Pentacam revealed that the astigmatism of the anterior corneal surface and the total cornea was 1.1 D (axis: 59.8°) and 1.0 D (axis: 35.6°), respectively. The horizontal (3°-183°) cross-section image displayed an IOL with a 1° tilt and 0.425 mm decentration. The patient reported no dysphotopsia or photophobia and was satisfied with the visual results. OPD-scan III revealed that higher-order aberrations in the right eye were slightly higher than those in the left eye. No suture-related or other serious complications were observed., Conclusion: The modified SSF-IOL technique can offer improved visual quality for patients with aniridia and aphakia by ensuring proper IOL positioning and reducing astigmatism., (© 2024. The Author(s).)

Background: Gillespie syndrome is a rare disorder caused by pathogenic variants in ITPR1 gene and characterized by the typical association of cerebellar ataxia, bilateral aniridia and intellectual disability. Since its first description in 1965, less than 100 patients have been reported and only 30 with a molecular confirmation., Methods: We present two additional cases, both carrying a loss-of-function variant in the Gly2539 amino acid residue. We describe the clinical evolution of the patients, one of whom is now 17 years old, and discuss the updated phenotypic spectrum of the disorder., Results: The study gives an overview on the condition, allowing to confirm important data, such as an overall positive evolution of development (with some patient not presenting intellectual disability), a clinical stability of the neurological signs (regardless of a possible progression of cerebellar atrophy) and ocular aspects, and a low prevalence of general health comorbidities., Discussion: Data about development and the observation of middle-aged patients lend support to the view that Gillespie is to be considered a non-progressive cerebellar ataxia, making this concept a key point for both clinicians and therapists, and for the families., (© 2024. The Author(s).)

Background-Aim: PAX6 is a key regulator of eye development and epithelial homeostasis in the cornea. When deficient, chronic corneal inflammation, neovascularization and limbal stem cell deficiency can occur. Here we investigated the potential of duloxetine, a generic serotonin reuptake inhibitor that can upregulate PAX6 in vitro, for its in vivo activity in the context of corneal inflammation., Methods: Duloxetine tolerance was tested in a human limbal stem cell line and isogenic CRISPR-knockout PAX6 +/- cells. C57BL/6-Wildtype mice were administered duloxetine eye drops at concentrations of 1 μM - 2 mM and tested for toxicity and corneal PAX6 expression. In LPS-induced corneal inflammation in mice, duloxetine's effect on PAX6 expression, corneal opacification and inflammatory responses were evaluated by in vivo corneal imaging, immunostaining, and whole-transcriptome microarray analysis., Results: No toxicity was observed in vitro for duloxetine concentrations up to 10μΜ. In vivo, duloxetine drops were well-tolerated up to 50 μM. Duloxetine drops at 10μΜ significantly upregulated PAX6 protein levels in the cornea by 30 % within 2 days. In the LPS model, duloxetine resulted in a sustained 33 % PAX6 protein upregulation in the cornea at 7 days, and in reduced opacity within 2 days, accompanied by a significant dampening of IL-17A signaling, neutrophil degranulation, microglial activation, macrophage markers, and MMP expression, despite non-significant changes in total inflammatory cell infiltration., Conclusion: Short-term administration of a repurposed generic drug, duloxetine, upregulates PAX6 protein levels in the cornea of mice and exerts an anti-inflammatory activity by dampening innate immune responses., Competing Interests: Declaration of competing interest The authors have no conflicts of interest to declare., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: To examine the clinical phenotype and genetic deficiencies present in Chinese aniridia families with PAX6 haplotype deficiency., Methods: A comprehensive questionnaire and ophthalmological assessments were administered to both affected patients and unaffected relatives. The clinical feature analysis included the evaluation of visual acuity, intraocular pressure, slit-lamp anterior segment examination, fundus photography, and spectral domain optical coherence tomography. To identify the mutation responsible for aniridia, targeted next-generation sequencing was used as a beneficial technique., Results: A total of 4 mutations were identified, consisting of two novel frameshift mutations (c.314delA, p.K105Sfs*33 and c.838&#95;845dup AACACACC, p.S283Tfs*85), along with two recurring nonsense mutations (c.307C>T, p.R103X and c.619A>T, p.K207*). Complete iris absence, macular foveal hypoplasia, and nystagmus were consistent in these PAX6 haplotype-deficient Chinese aniridia families, while corneal lesions, cataracts, and glaucoma exhibited heterogeneity both among the families and within the same family., Conclusion: In our study, two novel PAX6 mutations associated with aniridia were identified in Chinese families, which expanded the phenotypic and genotypic spectrum of PAX6 mutations. We also analyzed the clinical characteristics of PAX6 haplotype deficiency in Chinese aniridia families., (© 2024. Huazhong University of Science and Technology.)

In this case report, we explore a complex and rare presentation of simultaneous aniridia, xerophthalmia, corneal ulcer, and keratomalacia in a 21-year-old patient with a congenital history of nystagmus and progressively diminishing visual acuity. The patient experienced a recent exacerbation of ocular pain and redness, primarily in the right eye, which led to a comprehensive ophthalmological evaluation. Examination revealed corneal ulceration, vascularization, and the absence of the iris, posing a unique clinical challenge. In this report, we detail the personalized management and therapeutic strategies employed in this case, emphasising the need for an integrated and holistic approach to treating complex ocular conditions. The outcomes highlight the importance of tailored treatment plans and a thorough understanding of the interplay between various eye pathologies to achieve better patient outcomes., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Magdum et al.)

Aim: This study reports the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins subsequently diagnosed with Wilms tumour (WAGR syndrome)., Methods: Two monozygotic female twins were referred at age 2 months with bilateral corneal opacity. A diagnosis of Peters' anomaly associated to aniridia was made in both eyes of both twins. Physical examination and ultrasonography were carried out at 12 months of age to explore the possibility of WAGR-related anomalies, specifically Wilms tumour. DNA were isolated and subjected to whole exome sequencing., Results: Peters' anomaly associated to aniridia in both eyes as well as bilateral Wilms tumour in both children were diagnosed. Exome analyses showed a large heterozygous deletion encompassing 6 648 473 bp in chromosome 11p13, using Integrative Genomics Viewer and AnnotSV software., Conclusion: WAGR syndrome is a rare contiguous gene deletion syndrome with a greater risk of developing Wilms tumour associated with Peters' anomaly and congenital aniridia. However, co-occurrence of both anomalies was rarely reported in twins, and never in both eyes of monozygotic twins. Here, we report the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins with WAGR syndrome., (© 2024 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.)

Background/Objectives : Aniridia-associated keratopathy (AAK) is a potentially vision-threatening pathology in congenital aniridia, for which both the underlying etiopathogenesis and effective treatment remain unclear. Methods :This prospective study was conducted to assess and compare the short-term outcome after superficial keratectomy (SK) alone or in a combination with an amniotic membrane transplantation (AMT). Here, 76 eyes were enrolled in 76 patients with grade 4 AAK. In all eyes, in order to assess preoperatively the efficiency of the limbal epithelial stem cells (LESC), the presence of corneal epithelial cells in confocal microscopy was established. The analyses included: best corrected visual acuity (BCVA), the stage of AAK and the number of corneal quadrants involved in corneal neovascularization (CNV). Results : Six months after surgery, the mean BCVA was 0.05 and ranged from 0.002 up to 0.1 in both groups. Improvement in BCVA occurred in 94.29% patients when *SK alone* was performed, and in 92.68% when in combination with AMT. There were no statistically significant differences in the effect of therapy depending on the type of surgery, regarding BCVA, stage of AAK and the number of quadrants with CNV. Conclusions : SK alone is an effective procedure in short outcomes limited to six months for advanced AAK in association with LESC partial efficiency.

Different techniques for artificial iris implantation with or without an intraocular lens, depending on lens status, are described in the literature. We describe a surgical technique for a custom-made artificial iris and toric-intraocular lens intrascleral flange fixation. We modified the "Backpack" artificial iris implantation surgical technique to facilitate an accurate alignment of the toric-intraocular lens in a patient with aphakia, aniridia, and high asymmetric astigmatism secondary to blunt trauma. Two months after the surgery, uncorrected visual acuity was 20/30, corrected to 20/25 with a refraction of -2.00 in the diopter sphere with no residual astigmatism. The artificial iris implant and toric-intraocular lens were well-centered. The patient was satisfied with the visual and cosmetic outcomes. This procedure, however, is not complication-free as our patient developed uveitis and increased intraocular pressure during the postoperative period, which was treated successfully.

Purpose: To present the successful application of fibrin glue as a surgical adjunct in the management of complex rhegmatogenous retinal detachment (RRD). Methods: In this retrospective case series, fibrin glue was used as a surgical adjunct in 5 cases of complex RRD. In each case, standard pars plana vitrectomy and laser retinopexy were performed by the same surgeon. Fibrin glue was used intraoperatively as a tamponade to seal the breaks because the isolated use of conventional tamponade agents was not feasible given the variable nature of the complex RRDs, the anatomy of the eye, or an inability to maintain postoperative positioning. Results: In 1 patient previously treated for a large corneoscleral tear, fibrin glue was used to seal a large iatrogenic retinal break caused by a fragmatome-related surge that led to a quadrantic RD. In 2 patients treated for combined RRD, fibrin glue was used with silicone oil to manage recurrent RRD with incompletely drained thick subretinal fluid and blood. In 2 other cases, fibrin glue was applied to manage RRD in congenital aniridia with advanced glaucoma and aphakia. In all cases, retinal attachment without serious adverse effects was attained over a follow-up ranging from 4 to 6 months. Conclusions: Fibrin glue is an effective, safe surgical adjunct in complex RRD. It can be used to transiently seal a retinal break when use of a conventional tamponade agent is not possible or not sufficient alone., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

Background: Aniridia is a rare eye disorder with a high incidence of glaucoma, and surgical intervention is often needed to control the intraocular pressure (IOP). Here, we reported a case of illuminated microcatheter-assisted circumferential trabeculotomy (MAT) performed on an aniridic glaucoma patient following a previous failed angle surgery. The surgical procedures for aniridic glaucoma were also reviewed., Case Presentation: A 21-year-old man, diagnosed with aniridic glaucoma, came to our hospital consulting for the poor control of left eye's IOP despite receiving goniotomy surgery 3 years ago. The IOP was 26 mmHg with maximum topical antiglaucoma eyedrops. The central cornea was opaque and the majority of iris was absent. The gonioscopy and ultrasound biomicroscopy (UBM) demonstrated that 360° anterior chamber angle was closed. The whole exome sequencing of peripheral blood confirmed a 13.39 Mb copy number loss at chromosome 11p15.1p13, containing PAX6 and WT1 gene. The 360° MAT surgery was performed on his left eye. At 1-year follow-up, the IOP was 19mmHg with 2 kinds of topical antiglaucoma medications, and the postoperative UBM demonstrated the successful incision of the anterior chamber angle., Conclusions: The case presented here exhibited a case of aniridic glaucoma treated by MAT surgery. The MAT surgery may be an effective option for IOP control in aniridic glaucoma patients following a previous failed angle surgery., (© 2024. The Author(s).)

This qualitative study explored the motivators and barriers for genetic testing for individuals with aniridia. Semi-structured interviews were conducted with 8 participants. The main findings highlighted the complex and interrelated factors involved in the decision-making process, including family planning, learning about the specific pathogenic variant of the disease and having access to genetic testing. Benefits and potential risks of genetic testing for aniridia were also discussed. For participants, gaining knowledge about their condition was perceived as a benefit, while administrative issues and concerns around privacy were identified as risks. Increased access to quality information about genetic testing and to the service and associated resources are needed to better support people living with aniridia., (© 2023. The Author(s).)

Background: The ITPR1 gene encodes the inositol 1,4,5-trisphosphate (IP 3 ) receptor type 1 (IP 3 R1), a critical player in cerebellar intracellular calcium signaling. Pathogenic missense variants in ITPR1 cause congenital spinocerebellar ataxia type 29 (SCA29), Gillespie syndrome (GLSP), and severe pontine/cerebellar hypoplasia. The pathophysiological basis of the different phenotypes is poorly understood., Objectives: We aimed to identify novel SCA29 and GLSP cases to define core phenotypes, describe the spectrum of missense variation across ITPR1, standardize the ITPR1 variant nomenclature, and investigate disease progression in relation to cerebellar atrophy., Methods: Cases were identified using next-generation sequencing through the Deciphering Developmental Disorders study, the 100,000 Genomes project, and clinical collaborations. ITPR1 alternative splicing in the human cerebellum was investigated by quantitative polymerase chain reaction., Results: We report the largest, multinational case series of 46 patients with 28 unique ITPR1 missense variants. Variants clustered in functional domains of the protein, especially in the N-terminal IP 3 -binding domain, the carbonic anhydrase 8 (CA8)-binding region, and the C-terminal transmembrane channel domain. Variants outside these domains were of questionable clinical significance. Standardized transcript annotation, based on our ITPR1 transcript expression data, greatly facilitated analysis. Genotype-phenotype associations were highly variable. Importantly, while cerebellar atrophy was common, cerebellar volume loss did not correlate with symptom progression., Conclusions: This dataset represents the largest cohort of patients with ITPR1 missense variants, expanding the clinical spectrum of SCA29 and GLSP. Standardized transcript annotation is essential for future reporting. Our findings will aid in diagnostic interpretation in the clinic and guide selection of variants for preclinical studies. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society., (© 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.)

Congenital aniridia is caused by heterozygous mutations on the PAX6 gene leading to reduced amount of PAX6 protein (haploinsufficiency), abnormal eye development, and aniridia-associated keratopathy (AAK). This progressive corneal opacification resembles late-onset limbal stem cell (LSC) deficiency, leading to disrupted corneal epithelial renewal. The factors leading to AAK are not known and defects in native LSC differentiation and/or features leading to ocular surface dysfunction like inflammation and loss of innervation could contribute to development of AAK. Here, we produced induced pluripotent stem cells (hiPSC) from 3 AAK patients and examined whether PAX6 haploinsufficiency affects LSC lineage commitment. During LSC differentiation, characterization of the AAK lines showed lowered PAX6 expression as compared to wild type (WT) controls and expression peak of PAX6 during early phase of differentiation was detected only in the WT hiPSC lines. Whether it reflects developmental regulation remains to be studied further. Nevertheless, the AAK-hiPSCs successfully differentiated toward LSC lineage, in line with the presence of LSCs in young patients before cell loss later in life. In addition, patient-specific LSCs showed similar wound healing capacity as WT cells. However, extensive batch-related variation in the LSC marker expression and wound healing efficacy was detected without clear correlation to AAK. As development and maintenance of corneal epithelium involves an interplay between LSCs and their environment, the AAK-hiPSCs generated here can be further used to study the crosstalk between LSCs and limbal niche including, eg, corneal immune cells, stroma cells, and neurons., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: This study assessed the efficacy and safety of Ahmed valve implantation in patients with aniridic glaucoma for three consecutive years., Methods: Six adult patients (seven eyes) with Ahmed valve (AV) implants for aniridic glaucoma were enrolled in the study. The primary outcome measures were intraocular pressure reduction, glaucoma medication use, success rates, and visual acuity after AV implantation. A 30% reduction in IOP from baseline without the need for re-intervention was considered an effective treatment. The cessation of antiglaucoma medications was defined as complete success. Intraoperative and postoperative complications were included as secondary outcome measures. Measurements were performed preoperatively, at the first week, and 1, 3, 6, 12, 18, 24, 30, and 36 months postoperatively., Results: A total of seven eyes (6 patients) were evaluated 36 months after AV implantation. The mean ± SD values of IOP preoperatively at 1 day, 1 week, and 1, 3, 6, 12, 18, 24, 30, and 36 months postoperatively were 30.4 ± 4.0 mmHg, 14.6 ± 4.6 mmHg, 16.1 ± 4.6 mmHg, 20.7 ± 7.0 mmHg, 14.5 ± 2.7 mmHg, 16.5 ± 5.9 mmHg, 16.2 ± 4.0 mmHg, 16.3 ± 4.3 mmHg, 17.2 ± 10.1 mmHg, 17.6 ± 6.9 mmHg, and 18.2 ± 5.5 mmHg, respectively. At the last follow up, the mean IOP was reduced by 40.2%. The qualified success rate was 85.7%. One patient (one eye) at the last follow-up visit did not require antiglaucoma medications, resulting in a complete success rate of 14.3%. Intra- and postoperative mild or moderate subconjunctival bleeding was observed in all the patients. No other major/minor intraoperative or postoperative complications were noted., Conclusions: In long-term follow up, the AV implantation procedure is well-tolerated and relatively safe for reducing IOP in adult aniridia patients with glaucoma. These results should be validated through studies involving a larger patient cohort.

Purpose: There are currently limited treatment options for aniridia. In this context, 3D printed iris implants may provide a cost-effective, cosmetically acceptable alternative for patients with aniridia. The purpose of this study was to develop a proof-of-concept workflow for manufacturing 3D printed iris implants using a silicone ink palette that aesthetically matches iris shades, identified in slit lamp images., Methods: Slit lamp iris photos from 11 healthy volunteers (3 green; 4 blue; 4 brown) were processed using k-means binning analyses to identify two or three prominent colors each. Candidate silicone inks were created by precisely combining pigments. A crowdsourcing survey software was used to determine color matches between the silicone ink swatches and three prominent iris color swatches in 2 qualifying and 11 experimental workflows., Results: In total, 54 candidate silicone inks (20 brown; 16 green; 18 blue) were developed and analyzed. Survey answers from 29 individuals that had passed the qualifying workflow were invited to identify "best matches" between the prominent iris colors and the silicone inks. From this color-match data, brown, blue, and green prototype artificial irises were printed with the silicone ink that aesthetically matched the three prominent colors. The iris was printed using a simplified three-layer five-branch starburst design at scale (12.8 mm base disc, with 3.5 mm pupil)., Conclusions: This proof-of-concept workflow produced color-matched silicone prosthetic irises at scale from a panel of silicone inks using prominent iris colors extracted from slit lamp images. Future work will include printing a more intricate iris crypt design and testing for biocompatibility.

Purpose: Mutations in PAX6 gene (chromosome 11p13) encoding a transcriptional regulator involved in oculogenesis mostly present with aniridia. Aniridia is not uncommon in the Philippines but only limited information is available as yet. The purpose of this study was to present a novel, deletion mediated by complex rearrangement in PAX6 gene causing an isolated aniridia in a Filipino girl., Patients and Methods: The patient is an 8-year-old girl who came in due to leukocoria with associated nystagmus and esotropia. She presented with subnormal vision, nystagmus, aniridia, and cataractous lenses in both eyes. The family history reveals presence of the aniridia and cataract with the mother and a sibling. The patient underwent lens extraction without intraocular lens implantation bilaterally, where patient subsequently underwent intraocular lens implantation on her left eye. Systemic workup was performed including whole abdomen, renal ultrasound, blood chemistry, and urinalysis. Targeted cataract panel with WT1 and PAX6 genes revealed a novel, heterozygous PAX6 -inherited mutation from the mother. This variant is a complex rearrangement in PAX6 involving partial deletions of exons 3-5, including the initiator codon. Deletions of PAX6 are part of a contiguous gene deletion syndrome - Wilms tumor, aniridia, genitourinary anomalies, and intellectual disability syndrome - and therefore evaluation of the WT1 gene was necessary to rule out this life-threatening syndrome., Conclusion: This rare, complex rearrangement of multiple exons and deletions in PAX6 causing an isolated aniridia phenotype is probably the first reported case. The patient was managed by a multidisciplinary team and the guardians were counseled regarding the prognosis and complications.

Background: Childhood glaucoma is one of the most common causes of corneal opacity in childhood and is associated with various pathological corneal changes, including corneal enlargement, corneal clouding, and edema. Congenital glaucoma (CG) may cause a decrease in vision outcomes due to corneal opacity or clouding, which is often associated with stimulus deprivation amblyopia. Therefore, to create a balance between preventing amblyopia and sustaining corneal clearance, patients with CG can be managed with early penetrating corneal transplantation surgery along with advanced glaucoma management., Aim: To investigate the graft survival rate and factors affecting graft survival in patients with congenital glaucoma who underwent penetrating keratoplasty (PKP)., Study Design: Cross-sectional., Materials and Methods: Patients with congenital glaucoma who underwent PKP were retrospectively evaluated. The associations between age, corneal diameter, presence of ocular comorbidities, concurrent ocular surgeries with corneal graft, and visual outcomes were assessed., Results: Among the 30 eyes enrolled in the study, 6 (20%) had aniridia, 6 (20%) had Axenfeld-Rieger syndrome, and 18 (60%) were diagnosed with primary congenital glaucoma. Graft survival rates were 66.6% and 63.33% at 12 and 24 months, respectively. At the end of the follow-up, the overall graft survival rate was 60%. Statistical significance was observed between patient age at the time of surgery and graft failure ( p = 0.02). Graft failure was associated with a younger patient age. Functional vision was achieved in 53.3% of patients., Conclusions: The management of congenital glaucoma and its corneal complications is a delicate issue that requires great effort. PKP in congenital glaucoma was moderately successful in the present study. To provide functional vision, PKP could be the treatment of choice.

Background: To identify the disease-causing gene in a Chinese family affected with congenital aniridia., Methods: Patients underwent systematic ophthalmic examinations such as anterior segment photography, fundus photography, optical coherence tomography, and fundus fluorescein angiography. The proband was screened for pathogenic variants by whole exome sequencing (WES) and copy number variant (CNV) analysis. Real-time quantitative PCR (RT-qPCR) was applied to confirm the CNV results. Breakpoints were identified by long-range PCR followed by Sanger sequencing., Results: All seven members of this Chinese family, including four patients and three normal individuals, were recruited for this study. All patients showed bilateral congenital aniridia with nystagmus, except the son of the proband, who presented with bilateral partial coloboma of the iris. A novel heterozygous deletion (chr11:31,139,019-31,655,997) containing the 3' regulatory enhancers of the PAX6 gene was detected in this family. We also reviewed the reported microdeletions downstream of PAX6 in patients with aniridia., Conclusions: We identified a novel microdeletion, 517 kb in size located about 133 kb downstream of the PAX6 gene, responsible for congenital aniridia in this Chinese family, which expands the spectrum of aniridia-associated mutations in PAX6., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Congenital aniridia is a panocular disorder that is typically characterized by iris hypoplasia and aniridia-associated keratopathy (AAK). AAK results in the progressive loss of corneal transparency and thereby loss of vision. Currently, there is no approved therapy to delay or prevent its progression, and clinical management is challenging because of phenotypic variability and high risk of complications after interventions; however, new insights into the molecular pathogenesis of AAK may help improve its management. Here, we review the current understanding about the pathogenesis and management of AAK. We highlight the biological mechanisms involved in AAK development with the aim to develop future treatment options, including surgical, pharmacological, cell therapies, and gene therapies., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest to declare., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Introduction: Aniridia is a rare congenital panocular disease associated with varying degrees of visual acuity impairment., Objective: To assess the experiences of congenital aniridia patients in Hungary, with visual impairment using a questionnaire developed by the ANIRIDIA-NET., Patients and Method: Patients completed the Hungarian version of the 20-item ANIRIDIA-NET questionnaire with our assistance. The questionnaire covered demographic data, the most common complaints caused by the disease, the difficulties caused by low vision in different life situations and the frequency of low vision aids used in daily life., Results: 33 subjects (17 female [51.51%] and 16 male [48.48%]), 16 (48.5%) children and 17 (51.5%) adults completed the questionnaire, with an age of 25.69 ± 17.49 years (5-59 years). Daily photosensitivity was reported by 27 (81.8%), dry eyes by 5 (15.2%), tearing by 4 (12.1%), fluctuating vision by 3 (9.1%), and eye pain by 2 (6.1%) subjects. The majority of respondents said that personal communication with schoolmates (16 [48.5%]) or colleagues at work (11 [33.3%]) never caused difficulties because of their visual impairment. 29 people (87.9%) never needed help with daily routines at home, 24 (72.7%) with getting to school/work and 17 (51.5%) with various activities. 29 people (87.8%) never used low vision aids for communication, 23 (69.7%) for travelling, 20 (60.6%) for participating in social activities, 18 (54.5%) for studying/work., Conclusion: Although aniridia is associated with reduced visual acuity, the majority of people with congenital aniridia, especially in childhood, manage to cope with personal communication and various life situations without difficulty, despite their eye complaints. Low vision aids can be an important aid for them as they grow into adulthood and as they age. Orv Hetil. 2023; 164(34): 1342-1349.

Background: The genotype characteristics and their associated clinical phenotypes in patients with aniridia were analyzed to explore pathogenic variants using whole-exome sequencing., Methods: One patient with aniridia was enrolled at the Beijing Tongren Hospital. Comprehensive ophthalmic and general examinations were performed on the patient. DNA was extracted from the patient, and whole-exome sequencing was performed to identify the causative variant. The pathogenicity of the variant was predicted using in silico analysis and evaluated according to American College of Medical Genetics and Genomics guidelines. Relationships between genetic variants and clinical features were analyzed., Results: In addition to the classical aniridia phenotype showing complete iris aplasia, foveal hypoplasia, and ectopic lentis, the patient also exhibited spontaneous reattachment rhegmatogenous retinal detachment (SRRRD). Whole-exome sequencing identified a novel heterozygous variant, exon8:c.640&#95;646del:p.R214Pfs*28., Conclusions: The present study broadens the range of genetic variants described in aniridia and presents an aniridia patient with SRRRD., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Background: Aniridia is defined as missing iris tissue which can be partial, subtotal, or total. Characteristic clinical symptoms include photophobia and decreased visual acuity due to an increased light perception. In addition to this, disturbing cosmetic problems are prevalent. Even after implantation of an intraocular lens, patients often tend to be unsatisfied., Purpose: The answer to this problem lies in the implantation of an aniridic scleral fixation of intraocular lens (SFIOL), which has a central optical axis that acts as the refractive lens and a peripheral rim of a hyperpigmented area that mimics the iris and hence reduces photophobia. The purpose of the video was to demonstrate the use of black diaphragm intraocular lens (BDIOL) implantation, its surgical steps, and its outcomes., Synopsis: We report one such case where a young patient presented with post-traumatic aniridia with subluxated total cataract and spillover vitreous hemorrhage. He was subjected to a vitrectomy, cataract removal, and placement of an aniridic SFIOL with prolene 9-0 using the four-point fixation method. This gave an extremely gratifying outcome and solved both problems, that is, vision and photophobia. Highlight: Before implantation of the SFIOL, the patients had reduced visual acuity from aphakia and intolerable glare from aniridia. In this case-based approach and with relevant example, we tried to provide a solution for tricky scenarios like co-existing traumatic cataract and traumatic aniridia. The patient showed improved visual acuity and marked glare reduction after black diaphragm SFIOL implantation., Video Link: https://youtu.be/atl60WetFsM., Competing Interests: None

Introduction: Aniridia is a rare congenital vision-loss disease caused by heterozygous variants in the PAX6 gene. There is no vision-saving therapy, but one exciting approach is to use CRISPR/Cas9 to permanently correct the causal genomic variants. Preclinical studies to develop such a therapy in animal models face the challenge of showing efficacy when binding human DNA. Thus, we hypothesized that a CRISPR gene therapy can be developed and optimized in humanized mouse embryonic stem cells (ESCs) that will be able to distinguish between an aniridia patient variant and nonvariant chromosome and lay the foundation for human therapy., Methods: To answer the challenge of binding human DNA, we proposed the "CRISPR Humanized Minimally Mouse Models" (CHuMMMs) strategy. Thus, we minimally humanized Pax6 exon 9, the location of the most common aniridia variant c.718C > T. We generated and characterized a nonvariant CHuMMMs mouse, and a CHuMMMs cell-based disease model, in which we tested five CRISPR enzymes for therapeutic efficacy. We then delivered the therapy via lipid nanoparticles (LNPs) to alter a second variant in ex vivo cortical primary neurons., Results: We successfully established a nonvariant CHuMMMs mouse and three novel CHuMMMs aniridia cell lines. We showed that humanization did not disrupt Pax6 function in vivo, as the mouse showed no ocular phenotype. We developed and optimized a CRISPR therapeutic strategy for aniridia in the in vitro system, and found that the base editor, ABE8e, had the highest correction of the patient variant at 76.8%. In the ex vivo system, the LNP-encapsulated ABE8e ribonucleoprotein (RNP) complex altered the second patient variant and rescued 24.8% Pax6 protein expression., Conclusion: We demonstrated the usefulness of the CHuMMMs approach, and showed the first genomic editing by ABE8e encapsulated as an LNP-RNP. Furthermore, we laid the foundation for translation of the proposed CRISPR therapy to preclinical mouse studies and eventually patients with aniridia., (© 2023. The Author(s).)

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.

Total bilateral Limbal Stem Cell Deficiency is a pathologic condition of the ocular surface due to the loss of corneal stem cells. Cultivated oral mucosa epithelial transplantation (COMET) is the only autologous successful treatment for this pathology in clinical application, although abnormal peripheric corneal vascularization often occurs. Properly characterizing the regenerated ocular surface is needed for a reliable follow-up. So far, the univocal identification of transplanted oral mucosa has been challenging. Previously proposed markers were shown to be co-expressed by different ocular surface epithelia in a homeostatic or perturbated environment. In this study, we compared the transcriptome profile of human oral mucosa, limbal and conjunctival cultured holoclones, identifying Paired Like Homeodomain 2 ( PITX2 ) as a new marker that univocally distinguishes the transplanted oral tissue from the other epithelia. We validated PITX2 at RNA and protein levels to investigate 10-year follow-up corneal samples derived from a COMET-treated aniridic patient. Moreover, we found novel angiogenesis-related factors that were differentially expressed in the three epithelia and instrumental in explaining the neovascularization in COMET-treated patients. These results will support the follow-up analysis of patients transplanted with oral mucosa and provide new tools to understand the regeneration mechanism of transplanted corneas.

Aniridia, which is a rare congenital defect of the eye, consists of iris hypoplasia or aplasia, and additional ocular abnormalities. It is most commonly caused by autosomal dominant PAX6 gene mutations. However, in about 30% of cases, it is associated with chromosomal rearrangements in the 11p13 region. The aim of this study was to identify the potential PAX6 gene variants, which could cause the isolated aniridia. Eight patients with isolated aniridia were included in this study. MLPA analysis allowed in the past to exclude large structural rearrangements of the PAX6 and adjacent genes like WT1. Blood samples were collected from the patients (and their families in familial cases) and genomic DNA was extracted from peripheral blood leukocytes and buccal cells. The amplification of the 11 exons of the PAX6 gene was performed. Bidirectional Sanger Sequencing was conducted for the identification of the potentially pathogenic variants, and for the segregation analysis of the identified variant in the family. The results were analyzed with the use of CodonCode Aligner software. In three patients, aniridia was sporadic, whereas in another five cases, the eye defect was familial. The potentially pathogenic variants in the PAX6 gene were found in 6 out of 8 patients with aniridia. We identified four known (c.781C > T, c.607C > T, and c.949C > T twice), and two novel variants (c.258&#95;265del and c.495&#95;496insG). Point mutations in the PAX6 gene are the most frequent cause of aniridia. The investigation of the genetic background of the disease is essential for patients to evaluate recurrence risk in the offspring., (© 2023 Japanese Teratology Society.)

The inaugural Aniridia North America (ANA) Symposium was held on the first weekend in November 2021 in Charlottesville, VA, at the University of Virginia. The purpose of this meeting was to bring together an international group of scientists, physicians, patient advocacy groups, and individuals with aniridia to discuss recent advances in knowledge about aniridia and other congenital eye diseases and the development of potential treatments for congenital eye disorders using personalized medicine. Leaders in several areas of eye research and clinical treatment provided a broad perspective on new research advances that impact an understanding of the causes of the damage to the eye associated with aniridia and the development of novel treatments for this and related disorders. Here we summarize the research discussed at the symposium., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Given the various ocular manifestations of limbal stem cell insufficiency, an awareness of the genetic, acquired, and immunological causes and associated additional treatments of limbal stem cell deficiency (LSCD) is essential for providers. We performed a comprehensive review of the literature on the various etiologies and specific therapies for LSCD. The resources utilized in this review included Medline (PubMed), Embase, and Google Scholar. All English-language articles and case reports published from November 1986 through to October 2022 were reviewed in this study. There were collectively 99 articles on these topics. No other exclusion criteria were applied. Depending on the etiology, ocular manifestations of limbal stem cell deficiency range from dry eye syndrome and redness to more severe outcomes, including corneal ulceration, ocular surface failure, and vision loss. Identifying the source of damage for LSCD is critical in the treatment process, given that therapy may extend beyond the scope of the standard protocol, including artificial tears, refractive surgery, and allogeneic stem cell transplants. This comprehensive review of the literature demonstrates the various genetic, acquired, and immunological causes of LSCD and the spectrum of supplemental therapies available.

Congenital aniridia is a rare, pan-ocular disease causing severe sight loss, with only symptomatic intervention offered to patients. Approximately 40% of aniridia patients present with heterozygous nonsense variants in PAX6 , resulting in haploinsufficiency. Translational readthrough-inducing drugs (TRIDs) have the ability to weaken the recognition of in-frame premature termination codons (PTCs), permitting full-length protein to be translated. We established induced pluripotent stem cell (iPSC)-derived 3D optic cups and 2D limbal epithelial stem cell (LESC) models from two aniridia patients with prevalent PAX6 nonsense mutations. Both in vitro models show reduced PAX6 protein levels, mimicking the disease. The repurposed TRIDs amlexanox and 2,6-diaminopurine (DAP) and the positive control compounds ataluren and G418 were tested for their efficiency. Amlexanox was identified as the most promising TRID, increasing full-length PAX6 levels in both models and rescuing the disease phenotype through normalization of VSX2 and cell proliferation in the optic cups and reduction of ABCG2 protein and SOX10 expression in LESCs. This study highlights the significance of patient iPSC-derived cells as a new model system for aniridia and proposes amlexanox as a new putative treatment for nonsense-mediated aniridia., Competing Interests: The authors declare no competing interests., (© 2023 The Author(s).)

Genetic pediatric eye disease frequently leads to severe vision impairment or blindness. Voretigene neparvovec is the first approved gene therapy for an inherited retinal dystrophy (IRD). Voretigene neparvovec has been shown to be well tolerated and safe, with encouraging results in terms of efficacy, mainly when administered early in childhood. While we assisted at the first gene therapy available in clinical practice for an IRD, some questions remain unanswered, especially when gene therapy is delivered in young children. We review here the most recent reports and promising ongoing studies concerning various approaches on gene therapy in pediatric ophthalmology., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Daruich, Robert and Bremond-Gignac.)

Background: Haploinsufficiency of the transcription factor PAX6 is the main cause of congenital aniridia, a genetic disorder characterized by iris and foveal hypoplasia. 11p13 microdeletions altering PAX6 or its downstream regulatory region (DRR) are present in about 25% of patients; however, only a few complex rearrangements have been described to date. Here, we performed nanopore-based whole-genome sequencing to assess the presence of cryptic structural variants (SVs) on the only two unsolved "PAX6-negative" cases from a cohort of 110 patients with congenital aniridia after unsuccessfully short-read sequencing approaches., Results: Long-read sequencing (LRS) unveiled balanced chromosomal rearrangements affecting the PAX6 locus at 11p13 in these two patients and allowed nucleotide-level breakpoint analysis. First, we identified a cryptic 4.9 Mb de novo inversion disrupting intron 7 of PAX6, further verified by targeted polymerase chain reaction amplification and sequencing and FISH-based cytogenetic analysis. Furthermore, LRS was decisive in correctly mapping a t(6;11) balanced translocation cytogenetically detected in a second proband with congenital aniridia and considered non-causal 15 years ago. LRS resolved that the breakpoint on chromosome 11 was indeed located at 11p13, disrupting the DNase I hypersensitive site 2 enhancer within the DRR of PAX6, 161 Kb from the causal gene. Patient-derived RNA expression analysis demonstrated PAX6 haploinsufficiency, thus supporting that the 11p13 breakpoint led to a positional effect by cleaving crucial enhancers for PAX6 transactivation. LRS analysis was also critical for mapping the exact breakpoint on chromosome 6 to the highly repetitive centromeric region at 6p11.1., Conclusions: In both cases, the LRS-based identified SVs have been deemed the hidden pathogenic cause of congenital aniridia. Our study underscores the limitations of traditional short-read sequencing in uncovering pathogenic SVs affecting low-complexity regions of the genome and the value of LRS in providing insight into hidden sources of variation in rare genetic diseases., (© 2023. The Author(s).)

Purpose: Our purpose was to evaluate visual acuity in aniridia subjects and the more severely affected phenotype in WAGR syndrome subjects, and to assess potential impact on visual function., Materials and Methods: This was a retrospective comparative study of 25 aniridia subjects with nonsense mutations of PAX6 (50 eyes) and 25 WAGR syndrome subjects with large deletion mutations involving PAX6 (50 eyes). Aniridia subjects were age- and gender-matched with WAGR syndrome subjects in the Coordination of Rare Diseases at Sanford (CoRDS) database. Best-corrected ETDRS visual acuity measurements were converted to LogMAR visual acuity values, which were used to perform statistical analyses., Results: The age and gender distribution of the subjects was not statistically significantly different. The mean LogMAR values in aniridia and WAGR syndrome subjects were 0.95±0.53 and 1.51±0.99, respectively (P<0.001). In the better-seeing eye, mean LogMAR values were 0.78±0.15 in aniridia subjects and 1.40±0.88 in WAGR syndrome subjects (P=0.001). The mean LogMAR values for the better-seeing eye corresponded to Snellen visual acuity of 20/125 in aniridia subjects and 20/500 in WAGR syndrome subjects. This average visual acuity was worse than the threshold for profound visual impairment (WHO criteria) and legal blindness (AAO criteria) in WAGR syndrome but not in aniridia subjects. In analysis of both eyes, the visual efficiency was 34% in aniridia subjects and 2% in WAGR syndrome subjects., Conclusion: Visual acuity was significantly worse in WAGR subjects with multi-gene deletion mutations compared with aniridia subjects with nonsense mutations, which corresponded to differences in standard visual function thresholds. Our results suggest that visual acuity may indicate severity of ocular involvement and variability of phenotype in aniridia and WAGR syndrome., (© 2023 Krause et al.)

Purpose: This study is to describe the clinical outcome of penetrating keratoplasty combined with implantation of a novel intraocular lens with an artificial iris, aided by continuous vitreous chamber infusion, in patients with severe aniridia and corneal alterations., Methods: This was a prospective single-center case series study involving five patients with corneal alterations and aniridia. All subjects underwent simultaneous penetrating keratoplasty and implantation of a new intraocular lens with an artificial iris with the assistance of infusion into the vitreous chamber to regulate intraocular pressure during the surgical procedure. Visual acuity, corneal endothelial cell density, and intraocular pressure assessments were performed in the postoperative period. The final cosmetic outcome of the iris prosthesis placement was also evaluated., Results: In all cases, increased visual acuity and a good aesthetic result were observed in all affected eyes except one in which, despite the excellent aesthetic outcome, the eye was very hypotonic as it had high myopia and had undergone several previous surgeries., Conclusion: The single surgical procedure combining implantation of an intraocular lens-iris prosthesis with penetrating keratoplasty is an effective technique for the simultaneous treatment of aphakia and aniridia. However, larger series with longer-term follow-up are needed to definitively establish the benefits of this technique., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: The purpose of this study is to study the frequency, surgical transplantation technique and outcome in patients with aniridia-related keratopathy (ARK) with two-year follow-up period., Methods: A retrospective registry-study including all ARK cases performed in Sweden and Denmark between 2001 and 2016 and registered in the Swedish Cornea Transplant Registry., Results: A total of 36 eyes of 26 patients were subjected to corneal transplantation due to ARK during 2001 to 2016. Penetrating keratoplasty (PK) was the procedure of choice in 58.3% (n = 21) of the eyes, followed by a combination of PK and limbal stem cell transplantation in 13.9% (n = 5) and keratolimbal allograft in 13.9% (n = 5). Boston keratoprosthesis was used in 8.3% (n = 3), and anterior lamellar keratoplasty in 5.6% (n = 2). Thirteen of the procedures (36.1%) were retransplantations. Two years after surgery 26 cases were available to follow-up of which 16 of the grafts were functioning (61.5%). The median visual acuity showed a trend of improvement from hand motion to counting fingers., Conclusions: A majority of the ARK cases (61.5%) had a graft providing useful vision for the patient 2 years after corneal transplantation, but the visual gain was modest at best. Longer follow-up time is required to evaluate functional graft outcomes. Despite the introduction of limbal stem cell transplantation as a suitable treatment, PK was the most common surgical method in the present study., (© 2022 The Authors. Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation.)

Purpose: To study the frequency and types of strabismus in congenital aniridia, the presence of associated nystagmus, foveal hypoplasia, and congenital cataracts., Design: Prospective, single-center cohort study., Methods: A review was conducted of 379 medical records of congenital aniridia patients who had a follow-up at the Necker-Enfants malades University Hospital between 2006 and 2022; the target age was between 12 months and 30 years. Ophthalmologic and orthoptic assessments according to age were performed. Strabismus was further analyzed according to the type of aniridia, foveal hypoplasia, and laterality of congenital cataract., Results: Strabismus was diagnosed in 150 patients; 73 were included in the study (28 males [38%] and 45 females [62%]), with a mean age of 11.02 years. The mean follow-up was 24 months. Thirty-six (49.3%) presented with familial aniridia, and 37 (50.7%) presented with sporadic aniridia. Thirty-six (49.3%) were diagnosed with esotropia, 37 (50.7%) had exotropia. Nystagmus was detected in 70 patients (96%). Thirty-nine (53.4%) suffered from congenital cataract, 10 unilateral (25.7%) and 29 bilateral (74.3%). Foveal hypoplasia was found in 73 cases (100%); esotropia was predominant in all grades. PAX6 mutation was found in 56 patients (77%)., Conclusion: Strabismus is one of the clinical signs of congenital aniridia. The laterality of congenital cataracts seems to affect the type of strabismus. The grade of foveal hypoplasia has little impact on strabismus but is prevalent for nystagmus. Foveal hypoplasia affects optical focus, which is essential for binocularity; this could explain the poor binocular adjustment leading to strabismus without exotropia or esotropia predominance., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Congenital aniridia is a rare autosomal dominant congenital ocular disorder. Genetic studies suggest that heterozygous mutations in the developmental regulator PAX6 gene or the related regulatory regions leading to haploinsufficiency are the main cause of congenital aniridia. In this study, the clinical characteristics and pathogenic mutation of a four-generation Chinese family with congenital aniridia were investigated. All members recruited in this study underwent comprehensive ophthalmic examinations. Targeted gene capture sequencing and Sanger sequencing were performed to screen and confirm the candidate pathogenicity gene and its mutation. A multiple alignment of homologous sequences covering the identified mutation from different species was investigated, and the mutant protein structure was predicted using Swiss-Model. Additionally, the prediction of pathogenicity was analyzed using the ACMG Guidelines. Thirteen patients in this pedigree were diagnosed with congenital aniridia. A novel heterozygous frameshift mutation (c.391&#95;398dupATACCAAG, p.Ser133Argfs*8) in exon 7 of the PAX6 gene was identified in all affected individuals in the family. This study demonstrates that this frameshift mutation of the PAX6 gene might be the causative genetic defect of congenital aniridia in this family. This mutation is predicted to cause the premature truncation of the PAX6 protein, leading to the functional haploinsufficiency of PAX6, which may be the major molecular mechanism underlying the aniridia phenotype. To the best of our knowledge, this is the first report of a novel pathogenic PAX6 gene variant c.391&#95;398dupATACCAAG(p.Ser133Argfs*8) identified in a Chinese family with congenital aniridia.

The PAX6 gene plays an important role in ocular development. Mutations of the PAX6 gene may result in a series of ocular abnormalities, including congenital aniridia, anterior segment dysgenesis (ASD), progressive corneal opacification, glaucoma, and hypoplasia of the fovea and optic nerve, leading to reduced visual acuity and even blindness. This study aimed to describe the diversity of clinical features caused by PAX6 pathogenic variants in 45 Han Chinese patients from 23 unrelated families. All patients underwent detailed clinical assessment. Genetic testing was performed to identify pathogenic variations in the PAX6 gene by next-generation sequencing, minigene splicing assay, RT-qPCR, and long-range PCR. Twenty pathogenic variations were detected in the PAX6 gene from 12 pedigrees and 11 sporadic patients, of which 12 were previously reported and 8 were novel. The clinical phenotypes obtained as a result of the PAX6 gene mutations were complicated and vary among patients, even among those who carried the same variants. Genetic testing is helpful for differential diagnosis. Our genetic findings will expand the spectrum of pathogenic variations in the PAX6 gene. PAX6 pathogenic variants not only cause defects in ocular tissues, such as the iris and retina, but also lead to maldevelopment of the whole eye, resulting in microphthalmia., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Huang, Peng, Xie, Zhou, Wang, Wang, Gui and Li.)

Background: The aim of the study was to evaluate the impact of simultaneous amniotic membrane transplantation (AMT), status of the cornea (own cornea vs. graft) and underlying disease on the success and recurrence rates of autologous serum (AS) in therapy-resistant epithelial defects., Patients and Methods: Between 2007 and 2019, 990 treatments with AS in 703 eyes of 645 patients were retrospectively examined. The presence of erosion or ulcer, use of AMT, status of the cornea and the underlying disease were recorded. Epithelial closure rate within 4 weeks and the recurrence rate after epithelial closure were main outcome measures. The median observation period was 50 months., Results: Epithelial closure was seen in 73.6% and recurrence in 27.4%. AMT was used significantly more often for ulcers (p < 0.001) and recurrences (p = 0.048). Without AMT, there was a significantly higher epithelial closure rate (p < 0.001) and faster healing tendency (p < 0.001). There was no difference between own corneas and grafts with respect to epithelial closure rate (p = 0.47). On the grafts there was a significantly higher recurrence rate (p = 0.004) and faster recurrence (p = 0.03), especially ≤6 months after epithelial closure. The underlying diseases showed a significant difference in epithelial closure rate (p = 0.02) and recurrence rate (p < 0.001) with highest success in corneal dystrophies and lowest in congenital aniridia., Conclusion: AS is an effective therapeutic option for therapy-resistant epithelial defects. There was a high success rate for the grafts but with a higher tendency to develop recurrences. In cases of simultaneous AMT, a reduced success rate can be expected, due to the higher complexity of the given situation. AS can be used successfully in various underlying diseases, with limitations in case of congenital aniridia., (© 2022. The Author(s).)

Purpose: To explore the clinical phenotype and genetic defects of families with congenital aniridia., Methods: Four Chinese families with aniridia were enrolled in this study. The detailed ocular presentations of the patients were recorded. Whole exome sequencing (BGI MGIEasy V4 chip) was used to detect the gene mutation. Sanger sequencing was performed to validate the potential pathogenic variants, and segregation analysis was performed on all available family members., Results: By whole exome sequencing and Sanger sequencing, three recurrent mutations (c.112del, p.Arg38Glyfs*16; c.299G > A, p.Trp100* and c.718C > T, p.Arg240*) and one novel mutation (c.278&#95;281del, p.Glu93Alafs*30) of PAX6 were identified. All the mutations were co-segregated with the phenotype in the families. We also observed spontaneous anterior lens capsule rupture in aniridia for the first time., Conclusion: We report spontaneous anterior lens capsule rupture as a novel phenotype of aniridia and three recurrent mutations and one novel mutation of PAX6 in families with aniridia. Our results expanded the phenotype and genotype spectra of aniridia and can help us better understand the disease., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Guo, Zhang, Liu, Ji and Liu.)

Aniridia is a pan-ocular genetic developmental eye disorder characterized by complete or partial iris and foveal hypoplasia, for which there is no treatment currently. Progressive sight loss can arise from cataracts, glaucoma, and aniridia-related keratopathy, which can be managed conservatively or through surgical intervention. The vast majority of patients harbor heterozygous mutations involving the PAX6 gene, which is considered the master transcription factor of early eye development. Over the past decades, several disease models have been investigated to gain a better understanding of the molecular pathophysiology, including several mouse and zebrafish strains and, more recently, human-induced pluripotent stem cells (hiPSCs) derived from aniridia patients. The latter provides a more faithful cellular system to study early human eye development. This review outlines the main aniridia-related animal and cellular models used to study aniridia and highlights the key discoveries that are bringing us closer to a therapy for patients., Competing Interests: None

Paired box protein Pax-6 (oculothrombin) is a transcription factor that plays an important regulatory role in ocular, brain, and pancreatic development. Mutations of the PAX6 gene cause aniridia and Peters anomaly. Reduction in Pax-6 protein is also associated with ocular diseases such as dry eye. An electrochemiluminescence immunoassay method using the Meso Scale Discovery platform was developed to measure Pax-6 protein levels in corneal epithelial cells obtained by impression cytology. Impression cytology involves harvesting ocular epithelial cells by applying a polyethersulfone membrane patch briefly to the ocular surface using a commercially available EYEPRIM™ device. The epithelial cells that adhere to the membrane patch of the EYEPRIM™ device provide a biological sample which can be assayed for Pax-6 protein levels. Assay development identified an antibody pair capable of detecting purified recombinant Pax-6 protein produced in mammalian cells. The optimized assay has a dynamic range of 24 pg mL -1 to 100,000 pg mL -1 and a lower limit of quantification of 24 pg mL -1 . Assay selectivity was demonstrated using either HeLa or HEK293 cells transfected with inhibitory RNA. Finally, the method was validated by measuring Pax-6 protein levels in impression cytology acquired samples obtained using the EYEPRIM™ device from rabbit cornea., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

CRISPR/Cas9-based genome-editing therapies are poised to change the clinical outcome for many diseases with validated therapeutic targets awaiting an appropriate delivery system. Recent advances in lipid nanoparticle (LNP) technology make them an attractive platform for the delivery of various forms of CRISPR/Cas9, including the efficient and transient Cas9/gRNA ribonucleoprotein (RNP) complexes. In this study, we initially tested our novel LNP platform by delivering pre-complexed RNPs and template DNA to cultured mouse cortical neurons, and obtained successful ex vivo genome editing. We then directly injected LNP-packaged RNPs and DNA template into the mouse cornea to evaluate in vivo delivery. For the first time, we demonstrated wide-spread genome editing in the cornea using our LNP-RNPs. The ability of our LNPs to transfect the cornea highlights the potential of our novel delivery platform to be used in CRISPR/Cas9-based genome editing therapies of corneal diseases., Competing Interests: Declaration of Competing Interest D.D. declares no competing interests. B.R.L, A.M.H., P.K.W., E.M.S., S.Z.M.M. and the University of British Columbia (UBC) have filed patent application (PCT/US2019/0055472 and/or undisclosed provisional filing) on the delivery of ribonucleoprotein complexes in lipid nanoparticles. B.R.L, A.M.H. and P.K.W. are co-founders of Incisive Genetics Inc., which has the exclusive license to the intellectual property from UBC., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Disruption of any of the ocular development steps can result in ocular defects such as microphthalmia, coloboma and anterior segment dysgeneses including aniridia and cataract. All of these anomalies can be isolated or seen in association with each other. Except for aniridia (almost exclusively due to PAX6 mutations), most of these congenital ocular malformations are related to a wide genetic heterogeneity, as hundreds of genes are implied in ocular development. Here we describe a patient presenting with bilateral microphthalmia, congenital cataract, corneal dystrophy and iris hypoplasia, associated with extra-ocular features, who underwent an analysis of 119 ocular development related genes. Genetic testing revealed the presence of two truncating variants in the EPHA2 gene. While EPHA2 mutations are mainly known to be responsible for isolated dominant congenital cataract, we report here the first case of complex anterior segment dysgenesis caused by a biallelic EPHA2 mutation. This gene should be screened in case of aniridia with a negative PAX6 testing, as the ocular features of our patient clearly mimic those of PAX6 mutated patients. This observation enlarges the phenotype associated with EPHA2 variations and rise the insight of a possible PAX6-EPHA2 interaction that needs further investigations. Moreover, despite a great variability in ocular and extra-ocular phenotypes, mutations type and inheritance pattern, a possible genotype-phenotype correlation can also be drawn for this gene., Competing Interests: Declaration of competing interest Authors declared no conflict of interest., (Copyright © 2022. Published by Elsevier Masson SAS.)