Impotence is a symptom that manifests itself during sexual intercourse, so the diagnosis is primarily aimed at determining the presence of impotence, as well as centering around the possible causes of impotence. A delayed erection during sexual intercourse, or a lack of hardness or an erection that does not remain hard until ejaculation is a sign of impotence. If this symptom persists for a longer period of time, further tests are needed in order to find the cause if possible. Basic tests to diagnose impotence include nocturnal erectile function tests, blood endocrine metabolic tests or vascular function tests. If the patient usually has a good erection when he/she is having thoughts but not actually having sex, however, the impotence occurs when he/she has sex with his/her spouse or with a specific female partner, this is usually due to a psychological problem, and this type of person will need to have a nocturnal erection monitoring to determine the cause. If the patient is obese, he may have metabolic problems, or vascular function problems, and need to do blood sugar and lipid tests. For serious impotence patients need to do further ultrasound or imaging in order to rule out the presence of venous leakage and other conditions.