Comparison of Relational Corneal Thickness Measurements Obtained With Spectral Domain OCT of Topographically Normal and Suspicious Eyes
Narrative Responses:
Purpose
To compare corneal thickness measurements and ratios obtained with Spectral Domain OCT (SD-OCT) in normal patients and individuals with suspicious screening parameters (ectasia risk score = 3-4 without abnormal topography)
Methods
Retrospective consecutive series of 100 eyes from 50 patients with normal screening parameters (Normal) and 166 eyes from 83 patients with suspicious screening parameters (Suspect). Measurements compared included central, superior, and inferior thickness values, superior-inferior values (S-I), and inferior-central values at both the 2-5mm zone (I-C1) and 5-6mm zone (I-C2)
Results
Suspect corneas were thinner centrally (519 ± 30 vs. 545 ± 30, p<0.0001), superiorly (553 ± 32 vs. 567 ± 35, p<0.001), and inferiorly (529 ± 33 vs. 550 ± 35, P<0.0001). Superior-Inferior thickness value was significantly lower in suspects (23 ± 17 vs. 17 ± 11, P<0.0001). However, significant overlap was present for all variables measured
Conclusion
Suspect corneas were thinner in all regions measured and had a greater Superior to inferior thickness difference. However, no specific cut-off values appeared feasible to use for screening