Detection of Early Diabetic Change with Optical Coherence Tomography in Type 2 Diabetes Mellitus Patients without Retinopathy

Abstract

Purpose: To detect early diabetic damage in type 2 diabetes mellitus patients with no diabetic retinopathy (NDR) using optical coherence tomography (OCT) and to evaluate OCT as a clinical test. Methods: Thirty-two patients with NDR (n = 32) were enrolled. We examined retinal and retinal nerve fiber layer (RNFL) thickness using OCT. Two healthy normal populations were also enrolled for the retinal thickness (n = 48) and RNFL thickness (n = 34). Both OCT measurements were obtained in four areas (temporal, superior, nasal and inferior). The receiver operator characteristic (ROC) curve was generated to evaluate the predictor variables. Results: Comparing the normal and NDR eyes, retinal thickness significantly increased (p = 0.03) and RNFL thickness significantly decreased (p = 0.02) in the superior areas. The area under the ROC curve was 0.65 for the superior retinal thickness and 0.63 for the superior RNFL thickness. Conclusions: Both OCT measurements can detect early retinal damage in NDR patients.

Changes of macular and RNFL thicknesses measured by Stratus OCT in patients with early stage diabetes

“…These results are not consistent with the past reports. [12][13][14] One possible reason for this discrepancy may be the shorter duration of the DM in our NDR group than in the other studies, eg, 4.8 ± 4.4 vs 7.9 ± 7.3 years in the data of Sugimoto (Table 5). 14 Abbreviations: NDR, diabetic patients without diabetic retinopathy; OCT, optical coherence tomography; PPDR, preproliferative diabetic retinopathy; RNFL, retinal nerve fibre layer.…”

“…In addition, our findings showed that the macular thickness gradually increased with the duration of DM probably because of an increase in vascular permeability in the diabetic retinas. [12][13][14] Because of the short duration of DM, early reduction of macular thickness due to neuronal degeneration was not masked by the increase in macular thickness associated with vascular leakage.…”

“…10,11 Earlier studies have shown that the macular area is thicker and the RNFL is thinner in diabetic patients without diabetic retinopathy (NDR) and in those with preproliferative diabetic retinopathy (PPDR) compared to nondiabetic patients. [12][13][14] It has been suggested that a leakage of sera because of an increase in the vascular permeability may be the cause of the thickened retina. [12][13][14] At the early stage of DR, the RNFL thickness may be reduced because of the RGC death and axonal degeneration.…”

“…[12][13][14] It has been suggested that a leakage of sera because of an increase in the vascular permeability may be the cause of the thickened retina. [12][13][14] At the early stage of DR, the RNFL thickness may be reduced because of the RGC death and axonal degeneration. [1][2][3][4][5][6][7]14 But this does not explain why the macular area is thicker.…”

“…[12][13][14] At the early stage of DR, the RNFL thickness may be reduced because of the RGC death and axonal degeneration. [1][2][3][4][5][6][7]14 But this does not explain why the macular area is thicker. The reduced RNFL thickness is not detected in the macular thickness at the early stage of DR because an increased vascular permeability masks the effects of neuronal degeneration.…”