Corneal topographic and tomographic analysis of fellow eyes in unilateral keratoconus patients using Pentacam.
OBJECTIVE
To evaluate topographic and tomographic changes in fellow eyes in unilateral keratoconus (KCN) patients by comparing them with normal eyes.


METHODS
Retrospective comparative case series.


METHODS
Fourteen eyes of 14 patients with unilateral KCN and 34 eyes of 34 refractive surgery candidates were divided into 3 diagnostic groups using a Pentacam rotating Scheimpflug camera: advanced KCN eyes of unilateral KCN (KCN group, 14 eyes), normal fellow eyes of unilateral KCN (fellow eye group, 14 eyes), and refractive surgery candidates (normal group, 34 eyes). Topographic and tomographic parameters, which were obtained from Pentacam using sagittal curvature, elevation, and corneal thickness maps, were compared among the 3 groups. Receiver operating characteristic (ROC) curves were used to identify cutoff points in discriminating between fellow and normal eyes.


RESULTS
Keratometric asymmetry, topometric indices, and elevation differences (maximum - minimum) on both the anterior and posterior surfaces were statistically different (P < .05). On ROC curve analysis, keratometric asymmetry and topometric index were best at discriminating fellow eyes from normal, followed by elevation differences (maximum - minimum) on the posterior and anterior cornea surface.


CONCLUSIONS
Fellow eyes in unilateral KCN showed differences in several parameters that were not detectable with the Pentacam detection program, when compared with normal. However, each single parameter alone is not sufficient to detect early changes; thus, elevation indices as well as indices of anterior curvature should be considered together.
Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea; Department of Ophthalmology, Sahmyook Medical Center, Seoul, South Korea.
Gi Hyun
GH
Bae
Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Jae Ryung
JR
Kim
Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea; Chungju St. Mary's Eye Clinic, Chungju, South Korea.
Chi Hoon
CH
Kim
Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Dong Hui
DH
Lim
Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Eui Sang
ES
Chung
Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea. Electronic address: tychung@skku.edu.
Tae-Young
TY
Chung
D000293:Adolescent; D000328:Adult; D003315:Cornea / Q000473:pathology*; D019781:Corneal Topography; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000175:diagnosis*; D008297:Male; D009929:Organ Size; D012372:ROC Curve; D012189:Retrospective Studies; D012307:Risk Factors; D041623:Tomography, Optical Coherence; D014792:Visual Acuity; D055815:Young Adult