PO:34:205 | Optical coherence tomography angiography: a window on systemic sclerosis microangiopathy

Martina Orlandi¹, Tommaso Verdina², Filippo Santoro¹, Alessandra Carobbio³, Amelia Spinella¹, Marco De Pinto¹, Giorgia Roveta¹, Dilia Giuggioli¹ | ¹Internal Medicine Residency Program, Marche Polytechnic University, Ancona; ²Department of Clinical and Molecular Sciences, Marche Polytechnic University, Ancona; ³Department of Interna, Ancona, Italy

Background. Vasculopathy represents the primum movens in Systemic sclerosis (SSc) pathogenesis and the determining cause of many of the clinical manifestations of the disease. Optical coherence tomography angiography (OCTA) is a non-invasive imaging technique that allows visualization of retinal blood vessels, providing information on their structure and blood flow. Some studies have documented the presence of retinal vascular alterations in patients with SSc, even in early stages of the disease. The aim of the study is to evaluate the microangiopathic alterations in the retina of SSc patients and to evaluate their correlation with the clinical manifestations of the disease and the alterations at the capillaroscopy.

Materials and Methods. This is a case-control study comparing SSc patients with matched healthy controls (HC). The inclusion criteria for patients were: diagnosis of SSc or Very early SSc (VEDOSS), absence of maculopathy, no therapy with Hydroxychloroquine. The OCTA acquisition consisted of 3 x 3 mm scans of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) of both the macula and the optic nerve, performed using Canon OCT HS100 with dilated pupils. The vascular density (VD) and the vascular length density (VLD) as long as foveal avascular zone (FAZ) were then calculated using dedicated software (OCT-HS100 Angio Expert AX®). Retinal thickness in the fovea and in the perifoveal region was also measured.

Results. 82 eyes of 41 SSc patients (of which 11 were VEDOSS) were compared with 40 eyes of 20 HC. Patients showed significantly reduced VD values in all areas evaluated both at the SCP level (p<0.001) and at the DCP level (p<0.001). VLD values were also significantly reduced in patients compared to HC, both at the SCP (p<0.001) and DCP (p<0.001). Also at the optic nerve level, both VD and VLD values were significantly reduced at the SCP (p<0.001 for both) and at the DCP level (p=0.009 and p<0.001, respectively). Differently, FAZ values were not significantly different in patients versus HC. Retinal thickness of the parafovea was significantly increased in SSc patients (p=0.013). No significant difference was found by comparing the OCTA parameters of SSc patients with VEDOSS patients. Correlating retinal values with capillaroscopic parameters, the values of VD and VLD at the foveal level in DCP correlate with the presence of avascular areas (p=0.018 and p= 0.019, respectively) and neoangiogenesis (p=0.023 and p=0.025, respectively). In addition, the correlation between FAZ DCP and the presence of avascular areas is at the limit of significance (p=0.058).

Conclusions. This study highlights that ocular microangiopathy is present in scleroderma patients since the early stages of the disease and correlated with capillaroscopic alterations. These data confirm the systemic nature of scleroderma microangiopathy suggesting that OCTA may represent an important tool for its evaluation.