(A) T4 group. Some thyroid follicles showed dilation (DL) and lined by simple cuboidal epithelium (S) and it contains few colloid (CO). Other follicles were small in size with narrowed lumen and mild congestion of the blood vessels (C). 10X H & E. (B) Mild congestion of the blood vessels (C) and the thyroid follicles showed dilated (DL) and contain few colloids (CO). 10X H & E.