Fig. 1Measurement of the arterial wall thickness. We define the thickness as the distance between the intimal endothelium and external elastic lamina (EEL), which refers to the sum of the tunica intima and tunica media (elastic van Gieson stain).
Fig. 2Examples of six random measurements in the representative photomicrographs of the extrathyroid arteries, expressed as white straight lines, showing relatively even (A) and irregular (B) wall thicknesses. When the arteries exhibit alternative irregular wall thickness, as shown in (B), we alternate six random measurements between the thin and thick parts of the wall (elastic van Gieson stain).
Fig. 3Some nerve tissues (arrow) are identified in the interlobular septum, but not revealed in the thyroid parenchyma itself, as similarly reported in previous studies (S-100 protein, at 40×, inset at 200×).
Table 1Comparison of arterial wall thickness in all of the cases according to the location
Table 2Comparison of arterial wall thicknesses in the male and female patients according to the location in two studies
Table 3The differences of the arterial wall thicknesses between the extrathyroid and intrathyroid tissues according to sex in the two studies
Table 4Relationship of the extrathyroidal and intrathyroidal arterial wall thicknesses among the five age groups in the prospective cases