Table 7.
Comparison of the Current Study with Earlier Studies
| Sample Size (Eyes) | |||||||
|---|---|---|---|---|---|---|---|
| Study | KC Group | Control Group | Technology Used and Degree of KC Detected/Classified | Total Parameters Considered/Best Parameters Used | Area Under Curve | Sensitivity (%) | Specificity (%) |
| Current study | 74 | 104 | Sirius Scheimpflug tomography + geometric modeling Detects early and mild KC Classifies according to RETICS scale (grade I to grade IV+) | Combination of 27 demographic, clinical, pachymetric, and geometric parameters Age, gender, CDVA, Q8mm, and posterior MCT point deviation | Healthy, 0.87 (training) Early KC, 0.69 (training) Mild KC, 0.94 (training) | Healthy, 84 Early KC, 57 Mild KC, 63 | Healthy, 73 Early KC, 82 Mild KC, 97 |
| Hwang et al. (2018)8 | 30 | 60 (Post-LASIK) | Pentacam Scheimpflug tomography and SD-OCT imaging Detects asymmetric KC eyes (preclinical) No classification | Combines 9 tomography with 15 OCT variables 5 Scheimpflug variables 13 variables from both Scheimpflug and SD-OCT devices | Not mentioned | 83; 100 | 83; 100 |
| Shajari et al. (2018)30 | 27 (unilateral KC in fellow eye) | 50 | Pentacam Scheimpflug tomography Detects asymptomatic early KC No classification | 18 variables from Scheimpflug device Index of height decentration and index of vertical asymmetry | 0.79 (IHD); 0.72 (IHA) | Not mentioned | Not mentioned |
| Saad et al. (2010)10; Saad et al. (2012)31 | 40 FFKC + 31 KC | 72 | Orbscan IIz and OPD-Scan Detects FFKC (early) and KC (mild) No classification | 54 variables and 6 discriminant functions | N vs. FFKC, 0.98 N vs. KC, 0.99 | N vs. FFKC, 93 N vs. KC, 97 | N vs. FFKC, 0.92 N vs. KC, 100 |
| Qin et al. (2013)32 | 84 | 67 | RTVue Fourier-domain OCT Detects clinical KC No classification | 5 pachymetric variables Logistic regression formula | 0.98 | 90.5 | 95.0 |