Sensitivity and Specificity of Posterior Corneal Elevation Measured by Pentacam in Discriminating Keratoconus/Subclinical Keratoconus

Characterization of corneal structure in keratoconus

“…[14][15][16][20][21][22] Specifically, in keratoconus and also in keratoconus suspect, significantly larger values of BFS 14,16,21 and posterior elevation 15,16,22 have been reported (Figure 3). Schlegel et al 16 report a mean aconic astigmatism for the posterior corneal surface of 2.29 D G 1.71 (SD) in a sample of 48 keratoconussuspect patients using scanning-slit technology.…”

“…In the same sample, they also found a mean maximum posterior elevation of 0.0288 G 0.0102 mm at 1.0 mm of radius from the center. 16 De Sanctis et al 14 They obtained a mean value for this ratio of 1.874 G 0.532 in a sample of 43 keratoconus patients and of 1.103 G 0.462 in a sample of 23 keratoconus suspects using scanning-slit technology. 65 In addition, they found excellent keratoconus detection ability of the same ratio obtained using the anterior elevation data (cutoff: 0.5122, sensitivity: 99%, specificity: 95.2%).…”

“…The term keratoconus suspect was coined for designating corneas not showing biomicroscopic keratoconic signs but subtle topographic features similar to early stages of keratoconus. [14][15][16][17][18][19] In such conditions, other diagnostic tests and examinations may be helpful to confirm the potential presence of an incipient ectatic condition.…”

“…There is evidence that both anterior and posterior curvatures are affected in keratoconic eyes and also in keratoconus suspect eyes. 20 Likewise, significantly larger values of best-fit sphere (BFS) 14,16,21 and posterior elevation 15,16,22 have been reported in clinical keratoconic eyes and keratoconus suspect eyes. Therefore, manifestations of the ectasia also occur at the posterior corneal surface, even in early stages of the disease.…”

Impacto da análise do 'wavefront' na refratometria de pacientes com ceratocone

“…Nas últimas décadas, observou-se uma verdadeira revolução nos métodos diagnósticos em córnea, destacando-se o advento da topografia de reflexão dos discos de Placido (39,42) , tomografia com reconstrução 3-D (43)(44)(45)(46) , estudo biomecânico da córnea in vivo (47)(48)(49)(50)(51)(52) e a aberrometria ocular (53,59) . A análise da frente de onda (wavefront) ou aberrometria ocular total permite a caracterização das aberrações ópticas do olho de forma mais detalhada e complexa que a tradicionalmente realizada.…”