Abstract
Purpose
To compare the image quality between swept-source optical coherence tomography (SS-OCT) and spectral domain optical coherence tomography (SD-OCT), especially in eyes with media opacity.
Methods
Forty eyes without media opacity and 60 eyes with media opacity (30 eyes with cataract, 20 eyes with vitreous opacity, and 10 eyes with corneal opacity) were included in this study. SD-OCT and SS-OCT 6 × 6 macular scans were taken by a single operator. For image quality analysis, a total of 200 OCT images were subjectively graded by two trained retina specialists and measured quantitatively using the image quality factor (QF) built into the OCT devices.
Results
Compared to conventional SD-OCT, SS-OCT had statistically significantly better subjective and objective grades in the normal group, as well as each of the media opacity groups (p-value < 0.001). In both the subjective and objective grades, there was no significant difference according to the types of media opacity (QF: p = 0.188, subject grading scale [SGS]: p = 0.635) and the degree of media opacity (Group I: 20 ≤ QF < 50, Group II: 0 ≤ QF < 20; QF: p = 0.088, SGS: p = 0.051) in the superiority of image quality of SS-OCT to SD-OCT.
Conclusions
In this media opacity patient population, swept-source OCT is a superior diagnostic tool when compared with SD-OCT in both objective and subjective assessments, even in the ocular media opacity. This result may be useful in diagnosis and progression detection of retinal disease in media opacity eyes.
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Table 1.
Parameters | Media opacity (n = 60) | Total (n = 100) | ||||||||
---|---|---|---|---|---|---|---|---|---|---|
Normal (n = 40) | Cataract (n = 30) | Vitreous opacity (n = 20) | Corneal opacity (n = 10) | |||||||
Mean | p-value* | Mean | p-value* | Mean | p-value† | Mean | p-value† | Mean | p-value* | |
QF | <0.001 | <0.001 | <0.001 | 0.005 | <0.001 | |||||
SD-OCT | 67.61 ± 4.23 | 2 | 25.80 ± 13.63 | 16.56 ± 13.57 | 7.25 ± 4.12 | 3 | 38.82 ± 26.18 | |||
SS-OCT | 84.83 ± 9.96 | 6 | 65.67 ± 20.59 | 40.90 ± 24.96 | 2 | 26.30 ± 13.77 | 6 | 64.44 ± 26.97 | ||
SGS | <0.001 | <0.001 | <0.001 | 0.004 | <0.001 | |||||
SD-OCT | 7.80 ± 0.46 | 2.83 ± 1.53 | 2.35 ± 1.57 | 2.50 ± 1.78 | 4.69 ± 2.84 | |||||
SS-OCT | 8.98 ± 0.16 | 7.67 ± 1.47 | 5.95 ± 2.37 | 5.60 ± 3.20 | 7.64 ± 2.09 |
Table 2.
SD-OCT QF | Media opacity (n = 60) | Normal: QF ≥ 60 (n = 40) | ||||
---|---|---|---|---|---|---|
Group I: 20 ≤ QF < 50 (n = 28) | Group II: 0 ≤ QF < 20 (n = 32) | Normal: QF ≥ 60 (n = 40) | ||||
Mean | p-value* | Mean | p-value* | Mean | p-value* | |
QF | <0.001 | <0.001 | <0.001 | |||
SD-OCT | 32.55 ± 8.50 | 8.32 ± 6.17 | 67.61 ± 4.23 | |||
SS-OCT | 68.11 ± 16.28 | 35.75 ± 23.85 | 84.83 ± 9.96 | |||
SGS | <0.001 | <0.001 | <0.001 | |||
SD-OCT | 3.43 ± 1.14 | 1.91 ± 1.57 | 7.80 ± 0.46 | |||
SS-OCT | 8.00 ± 1.02 | 5.66 ± 2.56 | 8.98 ± 0.16 |
Table 3.
Type of media opacity | Mean | p-value* | |||
---|---|---|---|---|---|
Cataract (n = 30) | Vitreous opacity (n = 20) | Corneal opacity (n = 10) | |||
SSQF-SDQF† | 39.87 ± 18.86 | 24.34 ± 16.46 | 19.05 ± 9.96 | 31.22 ± 18.88 | 0.188 |
SSSGS-SDSGS‡ | 4.83 ± 1.44 | 3.60 ± 1.57 | 3.10 ± 1.45 | 4.13 ± 1.63 | 0.635 |