The value of keratometry and central corneal thickness measurements in the clinical diagnosis of Marfan syndrome.

PURPOSE: To explore the utility of keratometry and central corneal thickness (CCT) measurements in diagnosis of Marfan syndrome.
DESIGN: Retrospective chart review of 211 patients referred for ocular examination to rule out Marfan syndrome.
METHODS: Patients were categorized into Marfan or control groups using current clinical diagnostic criteria. Patients in whom Marfan syndrome could be neither diagnosed nor ruled out were categorized as inconclusive. Those with other connective tissue diseases were excluded from the study. T tests were performed on keratometry and CCT values, and odds ratios (ORs) were calculated.
RESULTS: Sixty-two patients were in the Marfan group and 98 patients were in the control group. Mean age of the Marfan group was 22.3 years vs 19.3 years in the control group (P = .23). Marfan patients had significantly lower keratometry and CCT values than controls (40.8 diopters (D) [Marfan] vs 43.3 D [control], P = 4.0 x 10(-19); and 543.5 microm [Marfan] vs 564.2 microm [control], P = 9.1 x 10(-6)). The maximum OR for keratometry (17.6) was calculated at 42 D. In Marfan syndrome patients without ectopia lentis, these values were 41.5 D (P = .00026 vs control) and 542.0 microm (P = .0011 vs control).
CONCLUSION: There was a highly significant difference in keratometry values between Marfan and control patients, and values less than 42 D could be used as a clinical diagnostic criterion for Marfan syndrome. Significant overlap in CCT values between Marfan and control patients suggests that further investigation is necessary to determine the clinical utility of CCT measurements.