Retinal nerve fiber layer thickness changes in diabetic peripheral neuropathy

Abstract

Objective To investigate retinal nerve fiber layer (RNFL) thickness changes using fourier domain optical coherence tomography (OCT) in patients with diabetic peripheral neuropathy (DPN).Methods One hundred and twelve cases with DPN diagnosed with type 2 diabetes were included in NDR group (61 cases) and NPDR group (51 cases).According the Clinical Scoring System (CSS),all patients were divided into mild group (41 cases),moderate group (38 cases) and severe group (33 cases).The control group included 48 patients with type 2 diabetes but non-DPN and NDR.The RNFL thickness was measured with fourier domain OCT.Each subject had circular scans around the optic nerve with a circle size of 3.45mm.The measuring parameter included the RNFL thickness of the temporal,superior,nasal,inferior quadrant and the mean of the whole layer.The RNFL thickness in different group was analyzed.Results The RNFL thickness of the mean and inferior quadrant in DPN group was descended obviously compared with the control group; Compared with the NPDR group,NDR group and the control group,the RNFL thickness of each quadrant were descended significantly.In NPDR group,the RNFL thickness of mean and inferior quadrant was significantly descended than that of the control group.In NPDR group the RNFL thickness of mean,superior and inferior quadrant were thinner than that in NDR group.In DPN cases,compared with mild group,moderate group and severe group,the RNFL thickness of each quadrant became thinner significantly.The RNFL thickness of each quadrant in severe group descended more significantly than that in mild group and moderate group.Conclusions The RNFL thickness become thinner before DR in DPN patients,and will reduce more significantly following the emerging of DR.Along with the aggravating of the DPN,the RNFL thickness descend progressively. Key words: Diabetic peripheral neuropathy; Retinal nerve fiber layer; Thickness