Corneal topographic lagoons: a potential new marker for post-traumatic recurrent corneal erosion syndrome.

BACKGROUND: Post-traumatic recurrent corneal erosion syndrome is a common clinical problem in which a definitive diagnosis is not always possible based solely upon biomicroscopic corneal signs. Indeed, in some cases archetypical symptoms or a preceding history of epithelial trauma cannot always be elucidated.

METHODS: Four groups of patients underwent corneal analysis using computer videokeratography. Group 1 (n = 11), subjects who presented with simple corneal epithelial trauma approximately three months before the study. Group 2 (n = 11), prospective analysis of subjects presenting with simple corneal epithelial trauma. Group 3 (n = 12), prospective analysis subjects with an established diagnosis of post-traumatic recurrent erosion syndrome. Group 4 (n = 135), prospective analysis of healthy control subjects.

RESULTS: Small, well delineated areas (1.0 to 1.5 mm in diameter) of markedly reduced corneal dioptric power (greater than 2 dioptres), which we have termed 'corneal topographic lagoons', were identified more commonly in eyes with recurrent corneal erosion syndrome and in eyes that had recently sustained corneal epithelial trauma; being found in 18.2% of Group 1, 9.1% of Group 2, 58.3% of Group 3 but only 1.5% of Group 4 (control).

CONCLUSIONS: The identification of areas of focal abnormality in the corneas of patients with post-traumatic recurrent corneal erosion syndrome remains a significant clinical problem. Corneal topographic analysis has demonstrated a focal abnormality, the 'corneal topographic lagoon', which is much more prevalent in cases of recent corneal trauma and recurrent corneal erosion syndrome than in the 'normal' population. Computerised videokeratography therefore adds a new tool to the armamentarium of the clinician seeking to identify and locate abnormalities in these difficult cases.