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Wessely-type immune ring following phototherapeutic keratectomy
K D Teichmann1, J Cameron, A Huaman
1King Khaled Eye Specialist Hospital, Riyadh, Kingdom of Saudi Arabia.
Insights
This case report details an immune ring observed after phototherapeutic keratectomy (PTK) in a patient with corneal scars. The ring, a dense white peripheral opacity, showed specific cellular changes on biopsy and resolved slowly over nine months.
Area of Science:
- Ophthalmology
- Corneal Surgery
- Immunology
Background:
- Immune rings are a known, though infrequently detailed, complication following photorefractive keratectomy (PRK).
- This report focuses on a specific instance of an immune ring developing after phototherapeutic keratectomy (PTK).
Observation:
- A dense white ring manifested in the peripheral cornea four days post-PTK in a patient with pre-existing superficial corneal scars.
- The patient received antibiotic treatment until cultures were negative for 48 hours.
Findings:
- Microscopic examination of a biopsy revealed focal keratocyte loss, nuclear fragments, polymorphonuclear leukocytes, and active fibroblastic response.
- Notably, lymphocytes and plasma cells were absent in the examined tissue.
- The clinical immune ring exhibited slow resolution, remaining visible for nine months after the PTK procedure.
Implications:
- This detailed case provides insight into the histological characteristics of immune rings post-PTK.
- Further studies on similar cases are necessary to elucidate the underlying mechanisms of immune ring formation after corneal refractive surgery.
- Understanding these mechanisms could inform future management strategies for corneal opacities and inflammatory responses.
Abstract:
Immune rings following photorefractive keratectomy (PRK) have been reported but have not been described in detail. This case report describes an immune ring after phototherapeutic keratectomy (PTK) in a patient with long-standing superficial corneal scars. A dense white ring formed in the peripheral cornea on the fourth day following surgery. The patient was treated with antibiotics until negative cultures were reported 48 hours later. A biopsy was taken and examined by light microscopy using hematoxylin-eosin and Mason's trichrome staining. The stroma showed focal keratocyte depopulation with nuclear fragments, occasional polymorphonuclear leucocytes, and an active fibroblastic reaction. No lymphocytes or plasma cells were seen. Clinically, the immune ring faded slowly and was still apparent 9 months after the PTK. Studies of similar cases are required to clarify the mechanisms responsible for this phenomenon.
