Evaluation of Keratoconus in Asians: Role of Orbscan II and Tomey TMS-2 Corneal Topography

Comparison of and correlation between anterior and posterior corneal elevation maps in normal eyes and keratoconus-suspect eyes

“…Lim et al 24 found that the mean values of maximum posterior elevation and irregularity were significantly higher in keratoconus and keratoconus-suspect eyes than in control eyes. 24 The existence of a correlation between the radius of curvature and the asphericity of the anterior and posterior surfaces in the same patient is controversial.…”

“…24 The existence of a correlation between the radius of curvature and the asphericity of the anterior and posterior surfaces in the same patient is controversial. Tomidokoro et al 25 found a significant positive correlation between spherical power, regular astigmatism, asymmetry, and higher-order irregularity of the anterior and posterior surfaces.…”

Videokeratoscopic indices in relation to epidemiological exposure to keratoconus

“…More recent prospective studies with larger patient samples have proposed that the majority of fellow eyes developing keratoconus might do so in the first 6 years following baseline diagnosis of the contralateral eye, with younger age and the magnitude of asymmetry being the principal risk factors [15]. These studies have reported a higher prevalence of asymmetric curvature patterns, between 70% [16] and 80% [15] in clinically normal fellow eyes. We found a greater prevalence of asymmetric patterns proportional to the exposure to risk of keratoconus (56% fellow eye, 44% OD relatives, and 32% OD controls).…”

Comparação entre dois sistemas de análise de topografia corneana

“…O novo sistema cromático facilita a captura da imagem com segmentação dos discos que se apresentam como anéis coloridos conseguindo através do reflexo corresponder ao algoritmo no cone, diferenciando-se da topografia convencional pela separação em três cores com nitidez e consequente digitalização e processamento da imagem (5) . (10) . Um trabalho anterior compara dois sistemas videoceratográficos em pacientes com ceratocone e os resultados não diferiram entre os dois aparelhos nas medidas da direção do astigmatismo e na diferença ceratométrica (11) .…”