Lab tests for Erectile Dysfunction
Hormones including Thyroid hormones, Prolactin, Testosterone are looked at. Variations in these hormone levels can adversely impact Erection. A lipid profile, typically on an empty stomach, blood sugar levels along with Glycosylated haemoglobin which tells us about sugar control over the last 3 months is also looked into. Increased sugar levels not only hamper the vascular process but also affect the nerves.
Nocturnal Penile Tumescence and Rigidity (NPTR)
Penile erections during Rapid eye movement sleep are common and is a normal physiologic mechanism irrespective of age. Rigiscan is a device used for measuring NPTR. A rigiscan is done by admitting the patient overnight and performing the test. A normal NPTR suggests that the nerves and the blood vessels are intact. An abnormal test is not of great value.
Color Doppler USG
This is done by means of an intracavernosal injection and monitoring with the help of Doppler ultrasound. The test is examiner dependent and is based on two values, namely the Peak Systolic velocity and the End Diastolic flow velocity. A resistance index value is also taken. These values are highly dependent on the sympathetic tone which basically means that in a highly anxious patient the values may not be accurate.
The nerves supplying the penis and the perineal muscles and which conduct impulses to and from the spinal cord may be checked. Nerve conduction studies with Velocity and latency testing can be done for completion sake.