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Traumatic aniridia with extensive episcleral pigmentation: a case report
Hsin-Yu Yang1,2, Catherine Jui-Ling Liu3,4
1Department of Ophthalmology, Taipei Veterans General Hospital, No. 201 Shipai Road, Sec. 2, Taipei, 11217, Taiwan.
BMC Ophthalmology
|February 9, 2022
Summary
Traumatic aniridia, a rare condition, occurred in a patient with prior glaucoma surgery. The iris displaced through a scleral fistula after contusion injury, not a corneal wound, highlighting a new mechanism for iris prolapse.
Area of Science:
- Ophthalmology
- Trauma Surgery
- Glaucoma Management
Background:
- Traumatic aniridia is documented following cataract surgery via clear corneal wounds.
- Previous cases suggest iris tissue extrudes through corneal incisions.
- Extensive episcleral pigmentation with traumatic aniridia is unreported.
Observation:
- A patient with prior trabeculectomy and cataract surgery presented with high intraocular pressure and near-complete iris loss post-contusion injury.
- Diffuse episcleral pigmentation and protruding uveal tissue at the trabeculectomy site were noted.
- Anterior segment examination revealed pigment particles, cells, and absence of iris tissue.
Findings:
- The iris tissue was displaced into the subconjunctival space through a scleral fistula, not a corneal wound.
- The scleral fistula acted as a pressure release point during the contusion injury.
- This case presents a novel mechanism of traumatic aniridia involving a scleral fistula.
Implications:
- Scleral fistulas may be a weak point for iris displacement in ocular trauma.
- Management of high intraocular pressure requires considering options like repeat trabeculectomy or glaucoma drainage devices.
- Careful consideration of episcleral pigmentation is necessary before certain glaucoma surgeries like transscleral cyclophotocoagulation.
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