Purpose: The aim of this study is to evaluate the retinal and choroidal structures in r- and nr-axSpA patients using spectral domain optical coherence tomography (SD-OCT) and to compare changes with healthy controls.
Methods: In this cross-sectional study, 70 axSpA patients (50 radiographic- and 20 nr-axSpA) and 50 healthy control subjects were included. Choroidal thickness (ChT), macular thickness, retinal nerve fiber layer (RNFL), and the ganglion cell complex (GCC) were measured by SD-OCT. For ChT values, seven lines at nasal and temporal were drawn at 500-μm intervals, centering the subfoveal sclerochoroidal junction. Analysis of the data was performed with the SPSS program. Mann-Whitney U test was performed for comparison of non-normally distributed continuous data; Student's t test was used for normal distributed data.
Results: No significant difference was observed between 70 (66% male; mean age 39.7 ± 10.4 years) axSpA patients (50 radiographic and 20 nr-axSpA) and 50 (mean age 41.2 ± 6.2 years) healthy control subjects (p 0.417). R-axSpA and nr-axSpA groups and control group were similar in terms of spherical equivalent, intraocular pressure, axial length, and body mass index (p 0.574, p 0.874, p 0.918, p 0.344, respectively). While mean macular and GCC thicknesses were significantly lower in the patient group than in the healthy group, there was no significant difference between the two groups in terms of RNFL thickness.
Conclusion: The present study showed that there was no significant relationship between markers and scores indicating disease activity and ChT, MT, RNFL, and GCC thicknesses. However, an increase in choroidal thickness and involvement of the retinal layers has also been demonstrated in patients with spondyloarthritis. In addition, the relationship between disease activity and retinal layer involvement is remarkable in the r-axSpA group.
Keywords: Axial spondyloarthritis; Choroidal thickness; Ganglion cell complex; Retina.