Impact of GH and IGF-I excess on nervous and vascular retinal structure in newly diagnosed acromegaly patients

Purpose: To investigate nervous and vasculare structure of retina in naïve acromegaly patients using Spectral Domain Optical Coherence Tomography (SD-OCT) and Optical Coherence Tomography Angiography (OCTA). Methods: Prospective case-control study. Twenty-four eyes of 12 naïve acromegaly patients (8 men, 4 women, mean age 49.1 ± 12.3 years) without chiasmal compression by pituitary adenoma and 24 eyes of 12 healthy controls were evaluated in this study. In both groups were performed SD-OCT, to assess ganglion cell complex (GCC) and retinal nerve fiber layers (RNFL) thickness, and OCTA, to assess the vessel density (VD) of the superficial capillary plexus (SCP), deep capillary plexus (DCP), radial peripapillary capillary (RPC) and choriocapillaris (CC). In patient group, OCT parameters were correlated to hormonal (GH, IGF-I) and metabolic (glucose and lipid profile) parameters. Results: GCC (p = 0.001) and RNFL average (p = 0.007) were significantly lower in patients than in controls. At the regression analysis, adenoma volume (p < 0.001) and diagnostic delay (p < 0.001) before diagnosis were the best predictor of GCC and RNFL average, respectively. VD in SCP (p < 0.001), DCP (p = 0.009), and RPC (p = 0.03) was significantly lower in patients as compared to controls. VD in RPC was significantly lower in patients with diagnostic delay above 8.5 years (median, p = 0.009) and fasting glucose above 90 mg/dl (median, p = 0.04) as compared to those below. Conclusion: As acromegaly patients exhibited an impairment either in nervous and in vascular retinal structure at diagnosis, even in the absence of chiasmal compression, SD-OCT and OCTA may represents potential tools to detect retinal damage in these patients.