The Relationship between Macular Pigment and Vessel Density in Patients with Type 1 Diabetes Mellitus

Aim: Macular pigment density and microvascular density on optical coherence tomography angiography (OCTA) were measured in a cohort of type 1 diabetes mellitus (T1DM) patients with retinopathy in the attempt to shed light on the pathophysiology of this condition. Methods: Eighty-two consecutive eyes of 59 patients with diabetic retinopathy examined at the Eye Clinic of the University of Naples Federico II from November 2016 to April 2017 were enrolled in this prospective study. Eighty normal eyes of 40 age-matched subjects without diabetes mellitus, without a history of glaucoma or evidence of intraocular surgery, and without retinal pathologic features constituted the control group. All patients and controls underwent a complete ophthalmic examination, best corrected visual acuity evaluation according to the ETDRS visual logMAR scale, measurement of intraocular pressure, OCTA, and evaluation of macular pigment. Results: There were no significant age differences between patients and controls. Both macular pigment measurements and vessel density measured by OCTA were significantly lower in patients than in controls. A moderate correlation was found between vessel density in all ETDRS sectors and macular pigment parameters. Conclusions: There was a reduction in macular pigment and in OCTA vessel density in T1DM patients with retinopathy, which may have prognostic value in determining disease progression.