Korean J Ophthalmol.  2012 Jun;26(3):169-173. 10.3341/kjo.2012.26.3.169.

Factors Associated with the Signal Strengths Obtained by Spectral Domain Optical Coherence Tomography

• Na JH
• Sung KR
• Lee Y

• KMID: 1376121
• DOI: http://doi.org/10.3341/kjo.2012.26.3.169

Abstract

PURPOSE
The aim of this study was to investigate factors associated with the signal strengths (SS, image quality scores) of optic disc and macular images obtained using Cirrus spectral domain optical coherence tomography (OCT).
METHODS
Ninety-two glaucomatous eyes were imaged using the Cirrus OCT macular and optic disc cube modes after pupil dilation. The influences of patient age, spherical equivalent, cataract presence, and cataract and glaucoma severity (visual field mean deviation), on the SS of images obtained using the two cube modes were compared between patients whose images showed high SS (SS > or =7) and low SS (SS <7).
RESULTS
The signal strength was significantly higher in images obtained using the macular cube compared to the optic disc cube mode (7.8 +/- 1.3 vs. 6.9 +/- 1.1, respectively; p = 0.001). Age and visual acuity of patients differed significantly between the high- and low-SS groups when data acquired using the optic disc (p = 0.027 and 0.012, respectively) and macular cube modes (p = 0.046 and 0.014, respectively) were analyzed. When the optic disc cube mode was employed, the extent of cataracts was significantly related to SS, whereas when the macular cube mode was used, none of the factors analyzed was significantly associated with SS.
CONCLUSIONS
Age, visual acuity, and the extent of cataracts were significantly associated with images of higher SS when the Cirrus OCT optic disc cube mode was employed.

Keyword

Glaucoma; Macular cube mode; Optic disc cube mode; Optical coherence tomography; Signal strength

MeSH Terms

Cataract/complications/pathology
Female
Glaucoma/complications/*pathology
Humans
Macula Lutea/*pathology
Male
Middle Aged
Nerve Fibers/*pathology
Reproducibility of Results
Retinal Ganglion Cells/*pathology
Retrospective Studies
Tomography, Optical Coherence/methods

Figure

• 

  Fig. 1 Correlation between the signal strengths of images obtained using the macular cube and the optic disc cube modes of Cirrus optical coherence tomography (correlation coefficient = 0.581, p < 0.001).

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