Congenital anterior segment ocular disorders: Genotype-phenotype correlations and emerging novel mechanisms.

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.

Duloxetine enhances PAX6 expression and suppresses innate immune responses in murine LPS-induced corneal inflammation.

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.

Phenotypic Spectrum and Natural History of Gillespie Syndrome. An Updated Literature Review with 2 New Cases.

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.

Glue-Assisted Retinopexy for Retinal Detachments Study Report 2: Fibrin Glue As a Surgical Adjunct in Complex Rhegmatogenous Retinal Detachment.

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.

Unravelling the Enigma of Ocular Complexity: Delving into Aniridia, Xerophthalmia, Corneal Ulcer, Keratomalacia, and Beyond.

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.

Analysis of Phenotypes Associated with Deficiency of PAX6 Haplotypes in Chinese Aniridia Families.

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_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.

Superficial Keratectomy Alone versus in Combination with Amniotic Membrane Transplantation in Aniridia-Associated Keratopathy and a Short-Term Clinical Outcome.

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.

Custom-Made Artificial Iris and Toric-Intraocular Lens Intrascleral Flange Fixation: A Case Report.

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.

A rare missense PAX6 mutation causes atypical aniridia in a three-generation Chinese family.

AIM: To investigate the molecular diagnosis of a three-generation Chinese family affected with aniridia, and further to identify clinically a PAX6 missense mutation in members with atypical aniridia. METHODS: Eleven family members with and without atypical aniridia were recruited. All family members underwent comprehensive ophthalmic examinations. A combination of whole exome sequencing (WES) and direct Sanger sequencing were performed to uncover the causative mutation. RESULTS: Among the 11 family members, 8 were clinically diagnosed with congenital aniridia (atypical aniridia phenotype). A rare heterozygous mutation c.622C>T (p.Arg208Trp) in exon 8 of PAX6 was identified in all affected family members but not in the unaffected members or in healthy control subjects. CONCLUSION: A rare missense mutation in the PAX6 gene is found in members of a three-generation Chinese family with congenital atypical aniridia. This result contributes to an increase in the phenotypic spectrum caused by PAX6 missense heterozygous variants and provides useful information for the clinical diagnosis of atypical aniridia, which may also contribute to genetic counselling and family planning.

Outcome of illuminated microcatheter-assisted circumferential trabeculotomy following failed angle surgery in PAX6 aniridic glaucoma: a case report and literature review.

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.

Efficacy and Safety of Plasma Rich in Growth Factor in Patients with Congenital Aniridia and Dry Eye Disease.

Congenital aniridia is a rare bilateral ocular malformation characterized by the partial or complete absence of the iris and is frequently associated with various anomalies, including keratopathy, cataract, glaucoma, and foveal and optic nerve hypoplasia. Additionally, nearly 50% of individuals with congenital aniridia experience symptoms of ocular dryness. Traditional treatment encompasses artificial tears and autologous serum. This study aimed to assess the effectiveness and safety of using platelet rich in growth factors (PRGF) plasma in patients with congenital aniridia and ocular dryness symptoms. METHODS: The included patients underwent two cycles of a 3-month PRGF treatment. At 6 months, symptomatology was evaluated using the OSDI and SANDE questionnaires, and ocular surface parameters were analyzed. RESULTS: The OSDI and SANDE values for frequency and severity demonstrated statistically significant improvements (p < 0.05). Ocular redness, corneal damage (corneal staining), and tear volume (Schirmer test) also exhibited statistically significant improvements (p < 0.05). No significant changes were observed in visual acuity or in the grade of meibomian gland loss. CONCLUSION: The use of PRGF in patients with congenital aniridia and ocular dryness symptoms led to significant improvements in symptomatology, ocular redness, and ocular damage. No adverse effects were observed during the use of PRGF.

Examination of Subbasal Nerve Plexus and Central Corneal Stromal Microstructure in Subjects With Congenital Aniridia, Using in Vivo Confocal Laser Scanning Microscopy.

PURPOSE: During life up to 70% of aniridia subjects develop aniridia-associated keratopathy (AAK). AAK is characterized by limbal stem cell insufficiency, impaired corneal epithelial cell differentiation and abnormal cell adhesion, which leads to centripetal spreading vascularization, conjunctivalization, and thickening of the cornea. Our aim was to examine the subbasal nerve plexus and central corneal stromal microstructure in subjects with congenital aniridia, using in vivo confocal laser scanning microscopy CLSM. METHODS: 31 eyes of 18 patients (55.6% males, mean age: 25.22 ± 16.35 years) with congenital aniridia and 46 eyes of 29 healthy subjects (41.4% males, mean age 30 ± 14.82 years) were examined using the Rostock Cornea Module of Heidelberg Retina Tomograph-III. At the subbasal nerve plexus, corneal nerve fiber density (CNFD), corneal nerve fiber length (CNFL), corneal total branch density (CTBD), and corneal nerve fiber width (CNFW) were analyzed using ACCMetrics software. Keratocyte density in the anterior, middle and posterior stroma was assessed manually. RESULTS: The CNFD (2.02 ± 4.08 vs 13.99 ± 6.34/mm2), CNFL (5.78 ± 2.68 vs 10.56 ± 2.82 mm/mm2) and CTBD (15.08 ± 15.62 vs 27.44 ± 15.05/mm2) were significantly lower in congenital aniridia subjects than in controls (p < 0.001 for all). CNFW was significantly higher in aniridia subjects than in controls (0.03 ± 0.004 vs 0.02 ± 0.003 mm/mm2) (p = 0.003). Keratocyte density was significantly lower in all stromal layers of aniridia subjects than in controls (p < 0.001 for all). Stromal alterations included confluent keratocytes, keratocytes with long extensions and hyperreflective dots between keratocytes in aniridia. CONCLUSIONS: Decrease in CNFD, CNFL, and CTBD, as well as increase in CNFW well refer to the congenital aniridia-associated neuropathy. The decreased keratocyte density and the stromal alterations may be related to an increased cell death in congenital aniridia, nevertheless, stromal changes in different stages of AAK have to be further analyzed in detail.

Bilateral Peters' anomaly, aniridia and Wilms tumour (WAGR syndrome) in monozygotic twins.

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.

Short Communication: Lived experience perspectives on genetic testing for a rare eye disease.

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.

Protein profiling of conjunctival impression cytology samples of aniridia subjects.

PURPOSE: Congenital aniridia is a rare disease, which is in most cases related to PAX6 haploinsufficiency. Aniridia associated keratopathy (AAK) also belongs to ocular signs of congenital aniridia. In AAK, there is corneal epithelial thinning, corneal inflammation, vascularization and scarring. In advanced stage AAK, typically, conjunctival epithelial cells slowly replace the corneal epithelium. Based on previous results we hypothesize that alterations of the conjunctival cells in congenital aniridia may also support the corneal conjunctivalization process. The aim of this study was to identify deregulated proteins in conjunctival impression cytology samples of congenital aniridia subjects. METHODS: Conjunctival impression cytology samples of eight patients with congenital aniridia [age 34.5 ± 9.9 (17-51) years, 50% female] and eight healthy subjects [age 34.1 ± 11.9 (15-54) years, 50% female] were collected and analysed using mass spectrometry. Proteomic profiles were analysed in terms of molecular functions, biological processes, cellular components and pathway enrichment using the protein annotation of the evolutionary relationship (PANTHER) classification system. RESULTS: In total, 3323 proteins could be verified and there were 127 deregulated proteins (p < 0.01) in congenital aniridia. From the 127 deregulated proteins (DEPs), 82 altered biological processes, 63 deregulated cellular components, 27 significantly altered molecular functions and 31 enriched signalling pathways were identified. Pathological alteration of the biological processes and molecular functions of retinol binding and retinoic acid biosynthesis, as well as lipid metabolism and apoptosis related pathways could be demonstrated. CONCLUSIONS: Protein profile of conjunctival impression cytology samples of aniridia subjects identifies alterations of retinol binding, retinoic acid biosynthesis, lipid metabolism and apoptosis related pathways. Whether these changes are directly related to PAX6 haploinsufficiency, must be investigated in further studies. These new findings offer the possibility to identify potential new drug targets.

Relationship between physical and psychological functioning and health-related quality of life in congenital Aniridia.

PURPOSE: Congenital aniridia is a serious eye disease characterized by absence of iris to various degrees. The aims of this study were to investigate health-related quality of life (HRQoL) in adults with aniridia and assess the relationships between HRQoL, psychological status, ocular health and obesity. METHODS: Twenty-nine adults with congenital aniridia (48% male, aged 18-79 years) participated. HRQoL was measured with SF-36 and the EQ visual analogue scale (VAS). The physical (PCS) and mental (MCS) component summaries of the SF-36 were calculated with higher scores indicating better HRQoL. Symptoms of anxiety and depression were measured using the Hospital Anxiety and Depression Scale (HADS). Obesity was assessed with the Patient-Reported Outcomes in Obesity (PROS). Sociodemographic characteristics, genetic variants and ocular and medical health variables were also analysed. RESULTS: The participants scored significantly lower in the general health domain of the SF-36 than the general population (65.2 vs. 75.3, p = 0.017). The EQ VAS score was also lower in the aniridia group (64.9 vs. 77.9, p = 0.021). Low PCS score was correlated with presence of ocular pain (p = 0.019), high HADS score (p = 0.017) and high PROS score (p = 0.009). Low MCS score was related to higher educational level (p = 0.038) and high HADS score (p < 0.001). High HADS and PROS scores were both related to low EQ VAS scores. CONCLUSION: Adults with congenital aniridia scored worse on certain measures of HRQoL than the general population. Poorer HRQoL was associated with increased symptoms of anxiety, depression and obesity and with presence of ocular pain.

Complex Chromosomal Rearrangement Involving Chromosomes 10 and 11, Accompanied by Two Adjacent 11p14.1p13 and 11p13p12 Deletions, Identified in a Patient with WAGR Syndrome.

Three years ago, our patient, at that time a 16-month-old boy, was discovered to have bilateral kidney lesions with a giant tumor in the right kidney. Chemotherapy and bilateral nephron-sparing surgery (NSS) for Wilms tumor with nephroblastomatosis was carried out. The patient also had eye affection, including glaucoma, eye enlargement, megalocornea, severe corneal swelling and opacity, complete aniridia, and nystagmus. The diagnosis of WAGR syndrome was suspected. De novo complex chromosomal rearrangement with balanced translocation t(10,11)(p15;p13) and a pericentric inversion inv(11)(p13q12), accompanied by two adjacent 11p14.1p13 and 11p13p12 deletions, were identified. Deletions are raised through the complex molecular mechanism of two subsequent rearrangements affecting chromosomes 11 and 10. WAGR syndrome diagnosis was clinically and molecularly confirmed, highlighting the necessity of comprehensive genetic testing in patients with congenital aniridia and/or WAGR syndrome.

Long-Term Clinical Outcomes of Ahmed Valve Implantation in Aniridic Glaucoma.

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.

Utilizing 3D Printing Technology to Create Prosthetic Irises: Proof of Concept and Workflow.

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.

Epidemiology of PAX6 Gene Pathogenic Variants and Expected Prevalence of PAX6-Associated Congenital Aniridia across the Russian Federation: A Nationwide Study.

This study investigates the distribution of PAX6-associated congenital aniridia (AN) and WAGR syndrome across Russian Federation (RF) districts while characterizing PAX6 gene variants. We contribute novel PAX6 pathogenic variants and 11p13 chromosome region rearrangements to international databases based on a cohort of 379 AN patients (295 families, 295 probands) in Russia. We detail 100 newly characterized families (129 patients) recruited from clinical practice and specialized screening studies. Our methodology involves multiplex ligase-dependent probe amplification (MLPA) analysis of the 11p13 chromosome, PAX6 gene Sanger sequencing, and karyotype analysis. We report novel findings on PAX6 gene variations, including 67 intragenic PAX6 variants and 33 chromosome deletions in the 100 newly characterized families. Our expanded sample of 295 AN families with 379 patients reveals a consistent global PAX6 variant spectrum, including CNVs (copy number variants) of the 11p13 chromosome (31%), complex rearrangements (1.4%), nonsense (25%), frameshift (18%), and splicing variants (15%). No genetic cause of AN is defined in 10 patients. The distribution of patients across the Russian Federation varies, likely due to sample completeness. This study offers the first AN epidemiological data for the RF, providing a comprehensive PAX6 variants spectrum. Based on earlier assessment of AN prevalence in the RF (1:98,943) we have revealed unexamined patients ranging from 55% to 87%, that emphases the need for increased awareness and comprehensive diagnostics in AN patient care in Russia.