Altinisik M.Kahraman N.S.Kurt E.Mayali H.Kayikcioglu O.2024-07-222024-07-22202201655701http://akademikarsiv.cbu.edu.tr:4000/handle/123456789/12788Purpose: To investigate the quantitative differences in optical coherence tomography angiography (OCTA) data between type 2 diabetes patients without clinically detectable diabetic retinopathy (DR) and healthy subjects. Methods: Thirty-nine patients with type 2 diabetes without DR and 41 age- and sex-matched healthy controls were recruited. The vessel density and foveal avascular zone (FAZ) area in the superficial capillary plexus and deep capillary plexus were measured using Nidek RS-3000 Advance® and compared between patient cohorts. Foveal vessel density (%) and FAZ (%) were also calculated. Results: A significant decrease in vessel density has been observed in the deep capillary plexus of the patients compared to healthy individuals (5.58 ± 0.98 mm2 versus 6.15 ± 0.89 mm2, p < 0.001). However, there were no significant differences in other parameters between cohorts (p > 0.05 in all parameters). Despite the decrease of deep capillary plexus density in the macular region, there was no significant change observed in foveal vessel density (p:0.44). It has also been observed that the duration of diabetes mellitus correlates with vessel density decrease in deep capillary plexus (R:–0.52; p < 0.001). In both groups, all parameters in deep capillary plexus were significantly higher than superficial capillary plexus (p < 0.001 for all parameters). Conclusions: OCTA can identify quantitative changes in DCP before the manifestation of clinically apparent retinopathy. DCP-VD reduction may be an earlier finding than FAZ enlargement. Despite the reduction of VD, FVD could be preserved for a certain period of time in DM patients. © 2022, The Author(s), under exclusive licence to Springer Nature B.V.EnglishDiabetes Mellitus, Type 2Diabetic RetinopathyFluorescein AngiographyFovea CentralisFundus OculiHumansRetinal VesselsTomography, Optical CoherenceVisual AcuityadultArticleblood vessel densitycapillaryclinical articlecross-sectional studydiabetic retinopathydisease durationfemalefoveal avascular zonehumanmalemiddle agednon insulin dependent diabetes mellitusoptical coherence tomography angiographyquantitative analysisretrospective studycomplicationdiabetic retinopathyeye fundusfluorescence angiographyoptical coherence tomographyproceduresretina blood vesselretina foveavascularizationvisual acuityArticle10.1007/s10792-022-02230-8