If the left adrenal gland is thickened, it is important to consider the possibility of adrenal nodule-like hyperplasia or adrenal adenoma. CT plain scan plus enhancement of the adrenal gland is recommended to effectively assess the size of the adrenal hyperplasia, its relationship to the surrounding area, and whether there is enhancement. The medical history should also be followed for hypertension, hypokalemia, and obesity to assess whether this adenoma is functional. Renin and angiotensin tests should be performed, cortisol tests should be done, 17-hydroxy and 17-ketone tests should be done, catecholamine concentration should be measured and high and low dose dexamethasone tests should be done to effectively determine whether the adrenal gland needs surgical treatment.