Factors affecting resolution of subretinal fluid after selective retina therapy for central serous chorioretinopathy

Abstract

The purpose of this study was to investigate the factors of clinical outcome of selective retina therapy (SRT) for central serous chorioretinopathy (CSC). This retrospective study included 77 eyes of 77 patients, who were treated with SRT for CSC and observed at least 6 months after the treatment. SRT laser (527 nm, 1.7 µs, 100 Hz) was used for treatment. The mean best-corrected visual acuity (logMAR), central macular thickness (CMT) and central choroidal thickness were changed from baseline to at 6-months follow-up with significant difference. The multivariate analyses found that the rate of change (reduction) in CMT was associated with focal leakage type on fluorescein angiography (FA) (p = 0.03, coefficient 15.26, 95% confidence interval 1.72-28.79) and larger baseline CMT (p < 0.01, coefficient - 0.13, 95% confidence interval - 0.13 to - 0.05). Complete resolution of subretinal fluid was associated with nonsmoking history (p = 0.03, odds ratio 0.276, 95% confidence interval 0.086-0.887) and focal leakage type on FA (p < 0.01, odds ratio 0.136, 95% confidence interval 0.042-0.437). These results may be useful for predicting the therapeutic effectiveness of SRT.

Figure 1

Schematic diagram of (a) the setup and (b) the treatment procedure of selective retina therapy (SRT).

Figure 2

Fluorescein angiography and horizontal line of optic coherence tomography images of patients at baseline (a, d), 3 months follow-up (b, e) and 6 months follow-up (c, f) after selective retina therapy (SRT). Extent of SRT irradiation (within yellow dotted line). (a)–(c): 47-year-old, non-smoker male with an 11-year history of vision loss in the left eye. The number of SRT irradiation was 8 and laser energy was ranged from 81 to 103 µJ (optoacoustic, OA value was ranged from 61 to 1009). Focal leakage was disappeared and complete resolution of subretinal fluid (SRF) was seen at 3- and 6-months follow-up. Central macular thickness (CMT) was decreased from 412 to 222 µm. (d)–(f): 51-year-old, smoker male with a 5-month history of vision loss and abnormal visual field in the left eye. The number of SRT irradiation was 10 and laser energy was ranged from 82 to 101 µJ (OA value was ranged from 98 to 476). Diffuse leakage and SRF was remained at 6 months follow-up. CMT was slightly decreased from 281 to 275 µm.

Figure 3

SRT irradiation energy and optoacoustic (OA) values. The scatter plot shows the correspondence between irradiation energy and optoacoustic value at each irradiation spot in all cases.

Figure 4

Time course of individual changes in best corrected visual acuity (BCVA), central macular thickness (CMT), and central choroidal thickness (CCT). (a) Proportions of patients whose BCVA was improved, unchanged, or worsened by ≥ 0.2 from baseline at 3 and 6 months after treatment. The proportion of patients with improved BCVA was 6.9% at 3 months and 7.8% at 6 months. (b) Proportion of patients whose CMT reduced, unchanged, or increased by ≥ 15% from baseline at 3 and 6 months after treatment. The number of patients with reduced CMT increased (from 67.5 to 72.7%) from 3 to 6 M. (c) Proportion of patients whose CCT reduced, unchanged, or increased by ≥ 15% from baseline at 3 M and 6 M after treatment. The number of patients with reduced CCT increased (from 1.3 to 10.4%) from 3 to 6 M.

Figure 5

Changes in central choroidal thickness (CCT) between the treated and fellow eye mean CCT at baseline was 351 ± 97 μm in treated eyes and 312 ± 92 μm in fellow eyes with a significant difference (p < 0.05). Mean change in CCT was − 1.0 ± 5.3% in treated eyes and − 0.1 ± 4.2% in fellow eyes after 1 month, − 3.6 ± 5.6% and 0.4 ± 4.8% after 3 months, and − 6.0 ± 6.3% and 0.2 ± 6.6% after 6 months, showing a significant difference after 3 and 6 months (1 month, p = 0.73; 3 months, p < 0.01; 6 months, p < 0.01).

Figure 6

Decision tree classified by the factors associated with the complete resolution of subretinal fluid (SRF). In this study, the overall complete resolution of SRF within 6 months after SRT was 46 out of 77 cases (59.7%). For patients with focal leakage on FA (n = 42), the complete resolution of SRF was seen in 33 cases (78.6%) whereas those with diffuse leakage (n = 35) that was seen in 13 cases (37.1%). For the non-smoker patients with focal leakage (n = 20), complete resolution of SRF was seen in 18 cases (90.0%), whereas for the smoker patients (n = 22) that was seen in 15 cases (68.2%). For the non-smoker patients with diffuse leakage (n = 22), complete resolution of SRF was seen in 10 cases (45.5%), whereas for the smoker patients (n = 22) that was seen only in 3 cases (23.1%).