Urethra is the tube through which urine flows out of human body from bladder and forms the lowest portion of the urinary tract. Some boys are found to have a curtain like membrane across the urethra. This membrane is called the posterior urethral valve and this valve slows down the flow of urine from bladder to the outside of the body.
How a posterior urethral valve functions?
Bladder is a muscular sac in which urine is stored. When the muscles of the bladder contrasts the urine is squeezed out of it and the sphincter muscles are opened and the urine flows out of the body through urethra. When there is a resistance due to posterior urethral valve the bladder is constantly working against this pressure. The bladder muscles have to work extra resulting in hypertrophy. The bladder is unable to expand properly when urine is stored inside it. This results in high pressure inside the bladder which gets transmitted to the kidneys resulting in its swelling which my adversely affect the functioning of the kidneys.
Diagnosis of Posterior urethral valves
In some baby's existence of posterior urethral valves are detected when they develop urinary tract infections. Most babies are diagnosed with the help of ultrasound scan done during the pregnancy. In babies with PU valves the urine stream will not be good and the urine will be passing in drops.
Treatment
Most of the treatment in PU valves is carried out with the help of a Paediatric cystoscope. This instrument inserted through the urethra allows the surgeon to view the bladder and make some minor operations without making any external cuts. With the help of cystoscope the PU valves are cut and the passage of the urinary tract is made free so that urine flows through it without any hindrance. Some other methods are also followed by surgeon is special situations to make sure that no urine remains collected inside the bladder.
What happens after the PU valves are cut?
Even though the PU valves have been cut the irreparable damages already done to the kidney has to be taken care of. The patient will require regular checkups and follow up action by a children's kidney specialist and a surgeon to minimize the problems already caused by the PU valves. Even if the urine flow is reestablished, frequent checkup with the surgeon will be necessary as a follow up to minimize the problems that may arise in future.