Microvascular Changes in OCT-angiography in Type 1 Diabetes Mellitus at the Onset of the Disease and After Optimization of Glycemic Control.

• Optical Coherence Tomography (OCT) Angiography (Diagnostic test): Measurement of retinal vessel density and distribution in the macula using new generation OCT device

Primary outcomes

• Vessel density [3 months]: Density of retinal vessels and perfusion in the macula

Secondary outcomes

• Vessel density [6 months]: Density of retinal vessels and perfusion in the macula

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Patients with Type 1 Diabetes at diagnosis of the disease (less than 7 days after diagnosis)
* Age equal to or greater than 18 years
* Signature of the informed consent by the patient / legal guardian.

Exclusion Criteria:

* Metabolic situation of ketosis or ketoacidosis, according to clinical criteria established in the protocol of the Endocrinology and Nutrition Service. The patient will be a candidate once the ketonemia is absent (value <1 mmol / L).
* Previous diagnosis of dyslipidemia and any previous lipid-lowering treatment
* Previous diagnosis of hypertension and any previous hypotensive treatment
* Previous diagnosis of any form of cardiovascular disease, including heart failure.
* Previous kidney disease, and presence of advanced kidney failure (estimated glomerular filtration rate <60 ml / min)
* Presence of diabetic retinopathy identifiable by conventional eye fundus or retinography, or other concomitant retinal vascular pathology (hypertensive retinopathy, venous occlusion, arterial obstruction, etc.)
* History or presence of retinal pathology that may alter its structure and / or the validity of the measurements (retinal detachment, epiretinal membrane, high myopia -understood as an axial length greater than or equal to 26mm measured by "IOL Master" biometry-, neovascular membrane, choroidal tumors, etc.)
* History of posterior uveitis or retinal vasculitis
* Glaucoma and neuro-ophthalmological pathology that can alter the neuroretinal structures.
* Refractive media opacity that prevents a correct acquisition of images and, therefore, their evaluation
* Dementia or intellectual disability that prevent proper collaboration when acquiring images

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• Ignacio Salvador, MD, Principal investigator, Fundació Institut de Recerca de l'Hospital de la Santa Creu i Sant Pau