Optical coherence tomography findings due to structural changes of the choroid and retina in Behçet's uveitis
Authors: Özçelik Soba Dilek , Çıtırık Mehmet , Berker Nilufer 
Published: May 2023

Aims: To evaluate the change in central macular and retinal nerve fiber layer (RNFL) thickness by using optical coherence tomography (OCT) and choroidal thickness by using enhanced depth imaging optical coherence tomography (EDI-OCT) in posterior uveitis of Behcet’s disease, to compare these results with the healthy population and to investigate the relationship between these parameters and Behcet’s disease duration, the number of ocular attacks and visual acuity.
Methods: Sixteen patients with the active phase and 33 patients with the inactive phase of Behcet’s disease, were followed up at Uvea Clinic in Ulucanlar Eye Training and Research Hospital, and 35 healthy cases were enrolled in this prospective study. All the individuals underwent visual acuity testing, intraocular pressure measurement, biomicroscopy, and fundus examinations. By using OCT and EDI-OCT central macular, RNFL thicknesses and subfoveal, at nasal 500 µm, nasal 1000 µm, temporal 500 µm, and temporal 1000 µm choroidal thicknesses were measured in all cases. The results of Behcet’s patients and healthy subjects were compared and the relationship between these parameters and Behcet’s disease duration, the number of ocular attacks, and visual acuity were assessed.
Results: Five patients (31,3%) were female, 11 (68,8%) were male in the active group and 8 patients (24,2%) were female and 25 (75,8%) were male in the inactive group. In active patients central macular and RNFL thicknesses were significantly thicker than inactive patients and the control group (p=0,000). In inactive patients with Behcet’s disease duration and the number of ocular attacks RNFL thickness was getting thinner than in active patients (p=0,023, p=0,007). In active, inactive patients and healthy subjects subfoveal choroidal thicknesses were 449,31±111,36, 318,21±94,81 and 364,34±82,88 µm respectively; at nasal 500 µm choroidal thicknesses were 437,44±105,51, 308,33±95,36 and 355,97±83,81 µm respectively; at nasal 1000 µm choroidal thickness were 418,25±112,71, 286,33±96,06 and 337,26±87,11 µm respectively; at temporal 500 µm choroidal thickness were 429,44±102,98, 305,67±88,56 and 360,51±83,78 µm respectively; at temporal 1000 µm, choroidal thickness were 407,44±102,64, 299,73±76,30 and 360,71±86,67 µm respectively. In active patients subfoveal, at nasal 500 and 1000 µm choroidal thickness was significantly thicker than inactive patients and control group (p<0,01), in inactive patients at temporal 500 and 1000 µm choroidal thickness were significantly thinner than control subjects (p<0,05).
Conclusion: By using OCT and EDI-OCT, in patients with active phase of Behcet’s disease central macular, RNFL, and choroidal thicknesses were found significantly thicker than inactive and control subjects. In inactive patients, choroidal thicknesses were significantly thinner than in healthy cases. In this study, the results showed that OCT and EDI-OCT findings were found to be beneficial in ocular Behcet’s disease diagnosis and follow-up period.