Changes in choroidal thickness in patients with diabetic retinopathy

Abstract

PurposeTo investigate the changes in choroidal thickness (ChT) following panretinal photocoagulation (PRP) for diabetic retinopathy (DR) and compare ChT in relation to DR severity.MethodsThirty-two eyes [19 eyes with proliferative DR (PDR) and 13 eyes with severe nonproliferative DR (NPDR)] for which PRP was necessary were analyzed. ChT was measured before PRP and at 1, 3, and 6 months after PRP using the swept-source optical coherence tomography. ChT of the 61 eyes matched with the PDR patients for the mean age and axial length was also measured and statistically compared in relation to severity.ResultsThe central field ChT before PRP treatment was 268.6 ± 104.5 µm (mean ± standard deviation) and was significantly decreased at 1, 3, and 6 months after PRP (254.5 ± 105.3, 254.2 ± 108.2, and 248.1 ± 101.8 µm, respectively, P < 0.0001). The central field ChT of severe NPDR (323.2 ± 61.3 µm) was significantly thicker than that of normal (248.3 ± 70.7 µm) and mild to moderate NPDR (230.0 ± 70.3 µm, P = 0.0455 and 0.0099, respectively). Moreover, the central field ChT of PDR (307.3 ± 84.1 µm) was significantly thicker than of mild to moderate NPDR (P = 0.0169).ConclusionChT significantly decreased after PRP, which continued for at least 6 months after treatment. ChT of severe NPDR and PDR was significantly thicker than that of mild to moderate NPDR. ChT of patients with DR was changed according to the treatment and severity of DR.Electronic supplementary materialThe online version of this article (doi:10.1007/s10792-017-0459-9) contains supplementary material, which is available to authorized users.

Thinner Average Choroidal Thickness Is a Risk Factor for the Onset of Diabetic Retinopathy

“…However, the relationship between CT and DR severity is unclear (Table 6). Ohara et al [21] and Kim et al [25] found that the subfoveal CT (SFCT) of patients with mild to moderate NPDR was slightly lower than that of those with no DR, and the SFCT of patients with severe NPDR and PDR was greater than that of those with no DR. Ohara et al [21] found that the SFCT was greatest in those with severe NPDR, and the SFCT in the severe NPDR and PDR groups was significantly higher than that in the mild to moderate NPDR groups. Kim et al [25] found that the CT of the PDR group was the thickest, and was significantly higher than that of mild to moderate NPDR and severe NPDR groups.…”

“…Some clinical studies have explored the changes in CT in DM patients, with contradictory results, noting that the choroid became thinner [14][15][16][17][18], thicker [19], or showed no obvious changes [20]. Contrary results also appear in studies investigating DR and its influence on CT [15,19,[21][22][23][24][25]. It is worth noting that some studies have found that the CT of DM patients without DR was significantly decreased compared to that of control individuals, suggesting that choroidopathy may occur earlier than DR and may be a risk marker for the early stage of DR [15,26,27].…”

Changes in choroidal thickness in advanced diabetic retinopathy treated with pan-retinal photocoagulation using a pattern scanning laser versus a conventional laser

“…[14] Several studies have shown that the SFChT decreases after PRP and that PRP-treated eyes have a smaller SFChT than naïve eyes. [4,8,9,[15][16][17] Zhang et al found that the SFChT decreased significantly 3 months after PRP, [8] as did Okamoto et al, [9] while Ohara et al found that SFChT decreased significantly 6 months after PRP [17] and Kang et al reported a significant reduction in the SFChT 12 months after PRP. [15].…”

Changes in choroidal thickness in advanced diabetic retinopathy treated with pan-retinal photocoagulation using a pattern scanning laser versus a conventional laser

“…[14] Several studies have shown that the SFChT decreases after PRP and that PRP-treated eyes have a smaller SFChT than naïve eyes. [4,8,9,[15][16][17] Zhang et al found that the SFChT decreased significantly 3 months after PRP, [8] as did Okamoto et al, [9] while Ohara et al found that SFChT decreased significantly 6 months after PRP [17] and Kang et al reported a significant reduction in the SFChT in the 12 months after PRP. [15] Despite the consistent finding of a decrease in the SFChT during long-term observation, reports on the more short-term studies have been conflicting but suggest a significant increase in SFChT at 1-12 weeks after PRP.…”