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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. [ABSTRACT FROM AUTHOR]

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.

Congenital aniridia is a pan ocular disorder characterized by partial or total loss of iris tissue as the defining feature. Classic aniridia, however, has a spectrum of ocular findings, including foveal hypoplasia, optic nerve hypoplasia, nystagmus, late-onset cataract, glaucoma, and keratopathy. The latter three are reasons for further visual compromise in such patients. This entity is often due to mutations in the PAX6 (Paired box protein Pax-6) gene. Recently, aniridia-like phenotypes have been reported due to non-PAX6 mutations as in PITX2, FOXC1, FOXD3, TRIM44, and CYP1B1 as well wherein there is an overlap of aniridia, such as iris defects with congenital glaucoma or anterior segment dysgenesis. In this review, we describe the various clinical features of classic aniridia, the comorbidities and their management, the mutation spectrum of the genes involved, genotype-phenotype correlation of PAX6 and non-PAX6 mutations, and the genetic testing plan. The various systemic associations and their implications in screening and genetic testing have been discussed. Finally, the future course of aniridia treatment in the form of drugs (such as ataluren) and targeted gene therapy has been discussed.

A comprehensive mutation screening procedure of PAX6 identifies 80% of mutations in aniridia. Run-on mutation and three novel nonsense mutations identified in the PAX6 gene in patients with aniridia. Based on the segregation of variant with the phenotype in the present study and previously published reports [Table 1], c. 1268A in PAX6 seems to be a mutation hot-spot for aniridia. [Extracted from the article]

Congenital aniridia is a pan ocular disorder characterized by partial or total loss of iris tissue as the defining feature. Classic aniridia, however, has a spectrum of ocular findings, including foveal hypoplasia, optic nerve hypoplasia, nystagmus, late-onset cataract, glaucoma, and keratopathy. The latter three are reasons for further visual compromise in such patients. This entity is often due to mutations in the PAX6 (Paired box protein Pax-6) gene. Recently, aniridia-like phenotypes have been reported due to non-PAX6 mutations as in PITX2, FOXC1, FOXD3, TRIM44, and CYP1B1 as well wherein there is an overlap of aniridia, such as iris defects with congenital glaucoma or anterior segment dysgenesis. In this review, we describe the various clinical features of classic aniridia, the comorbidities and their management, the mutation spectrum of the genes involved, genotype-phenotype correlation of PAX6 and non-PAX6 mutations, and the genetic testing plan. The various systemic associations and their implications in screening and genetic testing have been discussed. Finally, the future course of aniridia treatment in the form of drugs (such as ataluren) and targeted gene therapy has been discussed. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study is to analyze the outcome of various techniques for a custom-made iris prosthesis implantation as part of reconstructive anterior segment surgery following traumatic aniridia.Methods: This retrospective interventional study was done for 6 eyes that received an artificial iris as secondary reconstructive measure for photophobia and unsatisfactory vision following initial globe repair. Different implantation techniques were employed. These included simple sulcus implantation, implantation of a composite (iris prosthesis with attached intraocular lens) implant, and combinations with phacoemulsification, vitrectomy, and penetrating keratoplasty.Results: In all cases, the artificial iris was implanted successfully. In the follow-up period (1-48 months), postoperative complications included rhegmatogenous retinal detachment, prolonged intraocular inflammation, and corneal transplant decompensation due to graft rejection. There was no case of secondary glaucoma. Complications could be managed successfully. All patients showed improved best-corrected visual acuity and were satisfied with functional and cosmetic results.Conclusion: This case series highlights the different implantation techniques for reconstruction of the anterior segment after ocular trauma. The versatility of the custom-made iris implant accounts for a wide range of applications and the foldable material reduces the need for large incisions in the already traumatized eye. [ABSTRACT FROM AUTHOR]

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

Purpose: This study aimed to characterize an Asian Indian aniridia family for both the phenotype and genotype of the disease for a better clinical management. Methods: The phenotype and genotype of the affected and unaffected individuals in the aniridia family were evaluated. The subjects underwent a standard ophthalmic evaluation followed by molecular screening of PAX6 gene in the peripheral blood for mutation detection. Results: The three affected individuals had aniridia with several common features and an uncommon presentation of bilateral congenital ptosis. Two affected siblings, a brother and a sister, had aniridia, nystagmus, ptosis, increase in central corneal thickness, cataract, and foveal hypoplasia. The sister had features of glaucoma. The offspring of the sister had all the features except cataract and rise in intraocular pressure. Mutation screening of PAX6 gene helped in identifying a novel heterozygous pathogenic variation g. 31801757dupG (c. 216-19dupG) that resulted in a frameshift mutation that extended into exon 7. Based on the evaluation and diagnostic testing, the family was clinically managed along with genetic counselling. Conclusion: Molecular diagnostic testing helps in genetic counseling of the family with aniridia to understand the nature of the disease and detection of complications early for better management.

A 19-year-old female, having aniridia with secondary glaucoma, presented with uncontrolled intraocular pressure (IOP) in the right eye (RE) on maximal topical and systemic medications. On examination, RE had a subluxated cataractous lens with advanced cupping. She underwent trabeculectomy with mitomycin C. On postoperative day 1, as the IOP was 32 mmHg, one releasable suture was removed followed by gentle bleb massage. On postoperative day 2, suprachoroidal hemorrhage was noted, for which the patient underwent two drainage procedures. Hemorrhagic choroidals resolved completely 4 weeks after drainage.

Purpose: This study aimed to characterize an Asian Indian aniridia family for both the phenotype and genotype of the disease for a better clinical management.Methods: The phenotype and genotype of the affected and unaffected individuals in the aniridia family were evaluated. The subjects underwent a standard ophthalmic evaluation followed by molecular screening of PAX6 gene in the peripheral blood for mutation detection.Results: The three affected individuals had aniridia with several common features and an uncommon presentation of bilateral congenital ptosis. Two affected siblings, a brother and a sister, had aniridia, nystagmus, ptosis, increase in central corneal thickness, cataract, and foveal hypoplasia. The sister had features of glaucoma. The offspring of the sister had all the features except cataract and rise in intraocular pressure. Mutation screening of PAX6 gene helped in identifying a novel heterozygous pathogenic variation g. 31801757dupG (c. 216-19dupG) that resulted in a frameshift mutation that extended into exon 7. Based on the evaluation and diagnostic testing, the family was clinically managed along with genetic counselling.Conclusion: Molecular diagnostic testing helps in genetic counseling of the family with aniridia to understand the nature of the disease and detection of complications early for better management. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A 19-year-old female, having aniridia with secondary glaucoma, presented with uncontrolled intraocular pressure (IOP) in the right eye (RE) on maximal topical and systemic medications. On examination, RE had a subluxated cataractous lens with advanced cupping. She underwent trabeculectomy with mitomycin C. On postoperative day 1, as the IOP was 32 mmHg, one releasable suture was removed followed by gentle bleb massage. On postoperative day 2, suprachoroidal hemorrhage was noted, for which the patient underwent two drainage procedures. Hemorrhagic choroidals resolved completely 4 weeks after drainage. [ABSTRACT FROM AUTHOR]

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

This is a single case report of an elderly patient who had blunt trauma in an eye that had phacoemulsification and two trabeculectomies. She had good vision with a well-functioning bleb before the trauma. She presented during her routine follow-up visit for glaucoma with isolated aniridia and an intact globe. The capsular bag, zonules, and the intraocular lens were intact. The cupping was 0.8, and the rest of the fundus and macula were normal. Pigments were seen over the sclera extending posteriorly upto the fornix. Gonioscopy revealed only faint pigments at the fistula. Following the trauma, the intraocular pressure had increased to 26 mm Hg. The mechanism and the management of the glaucoma are discussed.

Implantation of iris-claw Artisan intraocular lens (IOL) is a surgical option for correction of aphakia; however, these IOLs have not been used in eyes with uveitis including Fuchs′ heterochromic iridocyclitis (FHI) due to possible risk of severe postoperative intraocular inflammation. In the case reported here, we secondarily implanted an Artisan IOL in a 28-year-old man with FHI who had aphakia with no capsular support due to a previous complicated cataract surgery. Enclavation was easily performed and no intraoperative complication was noted. Postoperative course was uneventful with no significant anterior chamber inflammation during 12 months of follow-up. Although there were few deposits on the IOL surface, the patient achieved a best-corrected visual acuity of 20/20 without developing glaucoma or other complications. Therefore, Artisan IOL may be considered for correction of aphakia in patients with FHI. However, studies on large number of patients are required to evaluate safety of the procedure.

We report a case of aniridia associated with congenital aphakia and secondary glaucoma. A 35-year-old male presented with aniridia, congenital aphakia and secondary glaucoma in both eyes. After an unsuccessful medical management, he underwent trabeculectomy with mitomycin C and anterior vitrectomy under local anesthesia in his left eye. Postoperatively, at the end of six months, intraocular pressure (IOP) in his left eye was controlled without medications. This case highlights the rare association of aniridia with congenital aphakia and secondary glaucoma.

Blunt trauma is usually associated with severe ocular damage particularly in eyes following cataract surgery. Small, self-sealing incision cataract surgery is changing the pattern of presentation of such cases, with relatively favorable outcomes. We describe a case of blunt trauma following phacoemulsification leading to aniridia.

Progressive anterior segment fibrosis syndrome (ASFS), after intraocular surgery in older children (=9 years) and adults with congenital aniridia, is described in the literature. In this report, we describe an unique case of ASFS in an infant with congenital aniridia following a combined trabeculotomy-ectomy and its recurrence after a descemet stripping endothelial keratoplasty. The ophthalmologists should be well aware of this entity and warn the parents about its possibilities. Use of immunomodulators or prolonged anti-inflammatory therapy may be considered to prevent its occurrence. [ABSTRACT FROM AUTHOR]

Congenital aniridia is a kind of eye disease characterized by complete or partial hypoplasia of the iris and is associated with other ocular anomalies including corneal opacity, glaucoma, and foveal hypoplasia. Heterozygous mutation of paired box 6 (PAX6) gene was identified in most cases of aniridia, with iatrogenic mutations accounting for about two-third of the cases and chromosomal rearrangements accounting for the other one-third. We report rare cases of variant aniridia, congenital iris ectropion associated with foveal hypoplasia in both a woman and her son with a mutation of PAX6 gene. To our knowledge, deletion c. 936delC in exon 8 of PAX6 gene has not been reported until now. [ABSTRACT FROM AUTHOR]

This is a single case report of an elderly patient who had blunt trauma in an eye that had phacoemulsification and two trabeculectomies. She had good vision with a well-functioning bleb before the trauma. She presented during her routine followup visit for glaucoma with isolated aniridia and an intact globe. The capsular bag, zonules, and the intraocular lens were intact. The cupping was 0.8, and the rest of the fundus and macula were normal. Pigments were seen over the sclera extending posteriorly upto the fornix. Gonioscopy revealed only faint pigments at the fistula. Following the trauma, the intraocular pressure had increased to 26 mm Hg. The mechanism and the management of the glaucoma are discussed. [ABSTRACT FROM AUTHOR]