|Year : 2021 | Volume
| Issue : 3 | Page : 298-300
Congenital aniridia- there's more than meets the eye
GN Subathra1, Indira Durai1, Sahithya Bhaskaran2
1 Department of Glaucoma Services, Aravind Eye Hospital and Postgraduate Institute of Ophthalmology, Madurai, Tamil Nadu, India
2 Department of Pediatric Ophthalmology and Strabismus Services, Aravind Eye Hospital and Postgraduate Institute of Ophthalmology, Madurai, Tamil Nadu, India
|Date of Submission||21-Feb-2021|
|Date of Decision||19-Apr-2021|
|Date of Acceptance||19-Apr-2021|
|Date of Web Publication||09-Sep-2021|
Dr. G N Subathra
Aravind Eye Hospital, 1, Anna Nagar, Madurai - 625 020, Tamil Nadu
Source of Support: None, Conflict of Interest: None
Congenital aniridia is a rare panocular disorder, leading to significant visual impairment which may present as an isolated ocular phenotype or in association with a systemic syndrome. We report the case of a 20-year-old female with congenital aniridia associated with ectopia lentis, horizontal pendular nystagmus, and foveal hypoplasia, leading to low vision subsequently limiting her social life. This case report highlights the importance of early intervention with low vision aids and focused rehabilitation to enhance the quality of life in individuals with congenital aniridia, thus preventing progression to permanent disability.
Keywords: congenital aniridia, low vision aids, rehabilitation
|How to cite this article:|
Subathra G N, Durai I, Bhaskaran S. Congenital aniridia- there's more than meets the eye. TNOA J Ophthalmic Sci Res 2021;59:298-300
| Introduction|| |
Congenital aniridia is a rare bilateral disorder characterized by partial or total hypoplasia of iris with the incidence of 1:64,000–1:100,000., It is a panocular disorder affecting not only the iris but also cornea, anterior chamber angle, lens, optic nerve, and fovea. Classical aniridia is due to PAX6 mutations, while other genes such as FOXC1, PITX2, and CYP1B1 contribute to aniridia-like phenotypes. The inheritance is autosomal dominant in two-third or sporadic in one-third of cases. Sporadic cases are often associated with systemic defects such as Wilms tumor, aniridia, genitourinary anomalies, and mental retardation (WAGR syndrome). Although the hallmark of aniridia is hypoplasia of iris tissue, the visual deterioration is attributed to associated ocular pathologies such as keratopathy, cataract, glaucoma, foveal or optic nerve hypoplasia, and nystagmus.,, Congenital aniridia is commonly affiliated with decreased vision with previous reports of as much as 86% of affected individuals having 20/100 vision or worse in the better eye. Here, we report a case of congenital aniridia with low vision, to emphasize the importance of early visual rehabilitation in such patient.
| Case Report|| |
A 20-year-old female presented with complaints of defective vision and photophobia in both eyes since childhood. She was evaluated around the age of 10 years and was advised spectacles. The patient did not comply with spectacle use and was lost to follow-up. There was no significant antenatal, perinatal, or family history. She had discontinued her schooling after high school, due to significant visual impairment.
General examination revealed no systemic associations. On ocular examination, unaided visual acuity in both eyes was 6/60 and N24. Cycloplegic retinoscopy recorded − 2.5DS/−3.00DC at 90 axis in the right eye and − 0.5DS/−3.00DC at 90 axis in the left eye. However, even with full refractive correction, there was no improvement in the existing visual acuity for distance and near. Anterior segment revealed total hypoplasia of iris, ectopia lentis [Figure 1], and pendular nystagmus in both eyes. Fundus examination revealed normal disc with dull foveal reflex. Intraocular pressure of the right eye 13 mmHg and the left eye 14 mmHg was documented by applanation tonometer, and on gonioscopy, rudimentary iris stump was observed in both eyes. The optical coherence tomography showed loss of foveal contour confirming foveal hypoplasia in both eyes [Figure 2].
|Figure 1: Slit-lamp image showing total hypoplasia of iris (yellow arrow) and ectopia lentis (white arrow) with inferior intact zonules|
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|Figure 2: Optical coherence tomography image showing loss of foveal contour suggestive of foveal hypoplasia|
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The treatment modality aimed to improve the functional vision of the patient. She was provided with a tint trial for her photophobia and her mobility improved considerably in daylight with red tint. Her distance vision improved to 6/36 with 4x telescope. With a 6x cut away magnifier, she was able to read continuous text of N8 with ease. She along with her family was counseled regarding vocational training options. Newer visual aids including android smart phones and special software programs in computer were elaborated to the patient and parents. Of the rehabilitation options provided, the patient preferred prescribed best glasses with tint, 6x cut away magnifier, and appropriate referral to vocational training and was prescribed the same. Ultrasound abdomen was advocated to rule out systemic and genitourinary associations. Family member's ocular screening to detect any variant of aniridia including subtle forms and genetic counseling was discussed with the parents.
| Discussion|| |
Congenital aniridia is a complex disorder which needs a precocious holistic approach of management. Congenital aniridia occurs as a phenotypically heterogeneous condition with varied presentation. Our patient presented with associated ocular features such as ectopia lentis and foveal hypoplasia. The conventional belief that vision of patients with aniridia is always poor and existing treatment options are bleak, is being changed through methodological approach, newer low vision aids, and artificial intelligence. Early intervention and focused rehabilitation are mandatory in such cases to get mainstreamed earlier in their life and improve the functional vision. The aim of rehabilitation is to improve the visual capacity through refractive error correction and low vision aids and enhance the quality of life through skill training.
The patient needs periodic follow up to exclude causes for further visual deterioration such as keratopathy, cataract, and glaucoma. The incidence of glaucoma associated with aniridia ranges from 6% to 75%, and hence, regular screening for intraocular pressure, optic disc changes, and visual fields are essential to detect glaucoma at an early stage. Since 70% of the individuals have an affected parent, screening of family members and genetic analysis for PAX6 gene mutation is essential to establish the inheritance. Early clarification on genetic status and inheritance will help to understand the genotype–phenotype correlation and would benefit from prompt treatment and surveillance of complications of aniridia. Moreover, offspring of an individual with isolated aniridia has 50% chance of inheriting the mutation and developing aniridia. In case of sporadic occurrence, periodic screening for Wilms tumor is mandatory early in the course of life.
| Conclusion|| |
A delayed diagnosis, poor follow-up, delay in institution of optical aids, and rehabilitation led to vision impairment which progressed to a disability impeding social and financial independence in the patient. Management of congenital aniridia needs multidisciplinary approach with ophthalmologist, optometrist, and rehabilitationist playing an important role in appropriate visual assessment, counseling for low vision aids, and timely rehabilitation which will prevent permanent vision impairment and improve the quality of life in patients.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient (s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
We would like to thank Mrs. Kumuragurupari, chief librarian, Aravind Eye Hospital, Madurai.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2]