Diabetic Retinopathy (DR) represents nowadays the major cause of visual loss in diabetic patients. Orbital Color-Doppler Ultrasound (OCDUS) and Spectral-Domain Optical Coherence Tomography (SD-OCT) are fast and non-invasive examinations: the first provides a quantitative method to measure the peak systolic velocity of central retinal artery (PSV-CRA) at the retro-bulbar level¹, the second allows high resolution cross/sectional images of the retina². Our aim was to study the clinical relationship between retinal blood flow abnormalities and morpho-structural retinal changes after percutaneous intraportal pancreatic islet transplantation (PIPIT)³.

8 (16 eyes) type-1-diabetic patients (5 with mild DR) were submitted to OCDUS and SD-OCT after PIPIT. Patients submitted to OCDUS were in supine position with closed eyelids; all the examinations were performed from the same operator, with a 5-12 linear probe (IU-22 ATL-Phlips). PSV-CRA evaluation was recorded at optic nerve head level. SD-OCT images were obtained using the Spectral OCT SLO (OPKO/OTI Ophthalmic Technologies Inc.) that combines SD-OCT imaging with confocal scanning laser ophthalmoscopy (SLO). A 360° radial scan of the macula was performed...

PSV-CRA (Fig.1), in patients with and without DR (Fig.2), respectively, was as follows: at baseline 7.4 ± 1.5 cm/sec versus 12.4 ± 0.5 cm/sec and at follow-up 8.3 ± 1.2 cm/sec versus 13.3 ± 0.5 cm/sec. Mild DR was directly related to PSV-CRA < 12 cm/sec during our observation period (p<0.001). SD-OCT documented a retinal thickness ≤ 250 microns and the MPCs(Fig.3) in 2 patients with worsening DR at follow-up. Cp and HbA1c, in patients with and without DR, respectively, were as follows: 0.9 ±...

In our study a relationship between morpho-structural retinal changes (MPCs) and flow abnormalities (PSV-CRA < 12 cm/sec), during islet transplantation, follow-up was found. This studyconfirmedthat an improvement of retinal blood flow after PIPIT,with OCDUS,was presentonly in the patients without DR. The MPCs, found by SD-OCT as the earliest sign of the progressive worsening DR, may appear during the worst hemodynamic and glycometabolic changes after PIPIT. The restoration of islet function with reduction of exogenous insulin requirement and better metabolic control after PIPIT could probably determine...

Venturini M, Fiorina P, Maffi P et al. Early increase of retinal arterial and venous blood flow velocities at color Doppler imaging in brittle type 1 diabetes after islet transplant alone. Transplantation. 2006; 81: 1274-7. Tremolada G, Pierro L, de Benedetto Uet al.Macular micropseudocysts in early stages of diabetic retinopathy. Retina. 2011; 31: 1352-8. Venturini M, Angeli E, Maffi P et al. Technique, complications, and therapeutic efficacy of percutaneous transplantation of human pancreatic islet cells in type 1 diabetes: the role of US. Radiology. 2005;...

Sergio Margari, MD Department of Radiology San Raffaele Scientific Institute Via Olgettina, 60 20132 Milan, ITALY Tel: +39.02.26436109 Fax: +39.02.26432165 E.mail: [email protected]