Lower urinary tract symptoms (LUTS) are a clinical condition commonly found in men over 50 years and also tend to rise progressively with age. Because of increased life expectancy, the number of patients with LUTS and the relative costs of diagnosis and treatment are still growing in Western countries. LUTS may include voiding and storage urinary symptoms or a combination of both, and they may be considered a consequence of benign prostatic obstruction (BPO) with its related effect on detrusor function Pressure flow study is the gold standard for the evaluation and grading BPO, although it is an invasive and time consuming test. Therefore, over the last few years, several alternative methods to pressure-flow study have been proposed to predict BPO, such as the ultrsound assessment of the bladder/detrusor wall thickness (BWT/DWT).