PURPOSE

This study aimed to compare the retinal thickness, vessel density, and perfusion density in patients with papillary thyroid carcinoma (PTC) and healthy controls using optical coherence tomography (OCT) and OCT angiography. And investigating the influence of serological parameters and carcinoma signs with retinal structural and microcirculatory in PTC patients.

METHODS

This cross-sectional study included 174 PTC patients (345 eyes) and 179 healthy subjects (358 eyes). Serological parameters (complete blood count, thyroid function, and lymphocyte subsets) and retinal thickness and flow parameters were compared between the two groups, and the correlations of retinal parameters with serological parameters in the PTC group. We investigated the effect of carcinoma signs (tumor size, focus location, lymphatic metastasis, surrounding tissue invasion, and BRAF mutations) on retinal parameters.

RESULTS

PTC patients exhibited significantly thinner retinal thickness and reduced vessel density and perfusion density in the macular superficial vascular plexus compared with healthy controls. Platelet-to-lymphocyte ratios and thyroglobulin were inversely correlated with retinal parameters, and CD4+ T cells were positively correlated. Aggressive carcinoma signs thicken the retinal thickness more than nonaggressive cases.

CONCLUSIONS

The findings indicate a trend toward macular thinning and retinal microcirculatory dysfunction in the PTC patients, and these changes may be related to chronic inflammation and immune dysregulation secondary to cancer progression. OCT and OCT angiography show potential as noninvasive tools for detecting subclinical retinal abnormalities in PTC patients, and retinal alterations may serve as a surrogate marker for systemic inflammation. However, further studies are needed to address confounders and establish causality.