PURPOSE: Measuring corneal biomechanical properties may help detect keratoconus suspect corneas and eliminate the risk of ectasia after LASIK. METHODS: Data of 504 eyes separated into three groups were retrospectively reviewed: normal (n = 252), keratoconus suspect (n = 80), and keratoconus (n = 172). Corneal hysteresis (CH) and corneal resistance factor (CRF) were measured with an ocular biomechanics analyzer. RESULTS: Mean corneal hysteresis was 10.6 +/- 1.4 (SD) mm Hg in the normal group, compared with 10.0 +/- 1.6 mm Hg in the keratoconus suspect group and 8.1 +/- 1.4 mm Hg in the keratoconus group. The mean CRF was 10.6 +/- 1.6 mm Hg in the normal group compared with 9.7 +/- 1.7 in the keratoconus suspect group and 7.1 +/- 1.6 mm Hg in the keratoconus group. Mean CH and CRF were significantly different between the three groups (P < 0.001). CONCLUSIONS: CH and CRF alone cannot be used to identify keratoconus suspect corneas. Analyzing signal curves obtained with the biomechanics analyzer may provide additional valuable information for selecting qualified patients for refractive surgery.
PURPOSE: Measuring corneal biomechanical properties may help detect keratoconus suspect corneas and eliminate the risk of ectasia after LASIK. METHODS: Data of 504 eyes separated into three groups were retrospectively reviewed: normal (n = 252), keratoconus suspect (n = 80), and keratoconus (n = 172). Corneal hysteresis (CH) and corneal resistance factor (CRF) were measured with an ocular biomechanics analyzer. RESULTS: Mean corneal hysteresis was 10.6 +/- 1.4 (SD) mm Hg in the normal group, compared with 10.0 +/- 1.6 mm Hg in the keratoconus suspect group and 8.1 +/- 1.4 mm Hg in the keratoconus group. The mean CRF was 10.6 +/- 1.6 mm Hg in the normal group compared with 9.7 +/- 1.7 in the keratoconus suspect group and 7.1 +/- 1.6 mm Hg in the keratoconus group. Mean CH and CRF were significantly different between the three groups (P < 0.001). CONCLUSIONS: CH and CRF alone cannot be used to identify keratoconus suspect corneas. Analyzing signal curves obtained with the biomechanics analyzer may provide additional valuable information for selecting qualified patients for refractive surgery.
Authors: Jiasong Li; Shang Wang; Ravi Kiran Manapuram; Manmohan Singh; Floredes M Menodiado; Salavat Aglyamov; Stanislav Emelianov; Michael D Twa; Kirill V Larin Journal: J Biomed Opt Date: 2013-12 Impact factor: 3.170
Authors: Ravi Kiran Manapuram; Salavat R Aglyamov; Floredes M Monediado; Maleeha Mashiatulla; Jiasong Li; Stanislav Y Emelianov; Kirill V Larin Journal: J Biomed Opt Date: 2012-10 Impact factor: 3.170
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