Evaluation of the impact of childhood obesity on retrobulbar hemodynamics and retinal microvasculature.

OBJECTIVE: To evaluate changes in retrobulbar ocular blood flow parameters by using Colour Doppler Imaging (CDI) and changes in foveal microvasculature by using Optical Coherence Tomography Angiography (OCTA) in pediatric obese patients and to compare them with a group of healthy children. METHODS: Children diagnosed with obesity without hypertension and diabetes (39 subjects, obese group) and age-matched healthy controls (26 subjects, control group) underwent CDI and OCTA imaging. Peak systolic velocity, end-diastolic velocity and resistivity index from ophthalmic, central retinal and posterior ciliary arteries on CDI; superficial and deep capillary plexus vascular density and foveal avascular zone area on OCTA imaging were obtained in each group. Central foveal and subfoveal choroidal thicknesses were also measured. CDI and OCTA parameters were compared between two groups. RESULTS: Peak systolic and end-diastolic velocities were found to be significantly lower in obese children than in controls in all three examined arteries (p < 0.05). Resistivity index values were similar between the groups. OCTA imaging did not reveal significant changes in superficial and deep capillary plexus vascular densities and foveal avascular zone area across analysed retinal regions between the groups. Subfoveal choroid was thicker in obese group than in control group (325.89 ± 52.77 µm vs. 304.52 ± 21.76 µm, p = 0.04). CONCLUSION: An apparent decrease was present in retrobulbar hemodynamics in obese children. This arises the possibility of early ocular macrovascular compromise rather than retinal microvascular impairment in childhood obesity.

Evaluation of Normal Thyroid Tissue and Autoimmune Thyroiditis in Children Using Shear Wave Elastography

Objective: Shear wave elastography (SWE) is a user-independent ultrasonographic technique that evaluates tissue elasticity. It is used especially in the evaluation of thyroiditis and thyroid nodules when it is capable of distinguishing malignant from benign thyroiditis in adults. To date, no studies have evaluated SWE in pediatric thyroid patients. The aim of this study was to measure the elasticity of normal thyroid tissue in children and adolescents using SWE and to investigate its role in the diagnosis of pediatric autoimmune thyroiditis. Methods: In total, 113 healthy children of whom 66 (58.4%) were girls and 57 children with autoimmune thyroiditis of whom 45 (78.9%) were girls were evaluated by SWE after B-mode ultrasound. The quantitative evaluation of normal thyroid tissue in healthy children and those with autoimmune thyroiditis was performed using shear wave velocity (SWV) values (m/s). Thyroid antibodies were consistent with autoimmune thyroiditis. Data were compared using descriptive and analytical statistics and receiver-operating characteristic curves. Results: The mean ± standard deviation (range) of SWV value in thyroid parenchyma of the healthy children was 1.82±0.3 m/s (1.32-2.37) m/s. There was a significant positive correlation between age and SWV values which increased with age. The average SWV value of thyroid parenchyma in children with autoimmune thyroiditis was 3.7±1.2 (2.59-6.25) m/s which was statistically significantly greater than in healthy children (p=0.00). The cut-off value for elasticity with the highest diagnostic accuracy was 2.39 m/s; sensitivity and specificity were 97.4% and 100% respectively. There was no correlation between elasticity, thyroid function tests and autoantibody concentrations (p>0.05). Conclusion: SWE is a useful imaging method that can be used with routine ultrasonography in evaluation of the thyroid in children.