I work at Sunnybrook Hospital, a very large adult hospital. In 1974, they opened a spinal cord injuries unit to take care of people hurt in motor vehicle accidents, falls, etc. Those with a spinal cord injury often have neurological problems with their bladder and Sunnybrook has been able to foster an interest in the management of people with a neurogenic bladder. As spina bifida almost always results in a neurogenic bladder, over the years we have been able to develop that type of interest and expertise and can offer a range of management to people who have neurogenic bladder. The term "neurogenic bladder" means there is a problem with the nerve supply to the bladder.
I would like to talk about adult issues. At Sunnybrook, we do not deal with pediatric conditions; they are done at other places, in particular, the Hospital for Sick Children. The important issues that I would like to talk about are urinary incontinence and urinary tract management, prevention of kidney failure, and also touch briefly on sexual function and fertility as it relates to the neurogenic bladder.
Let me start with just a brief overview of the anatomy; the anatomy of the urinary tract consists of the kidneys and the tubes from the kidneys, called the ureters. This is called the upper urinary tract and is the same in both men and women. The lower urinary tract consists of the bladder and the urethra. There is, of course, quite a difference between men and women. In women, the uterus and the ovaries are not parts of the urinary tract, however due to their proximity, they are considered very important when one is assessing the lower urinary tract.
Incontinence is seen more often in women than in men for a number of reasons. One of them is that the urethra is shorter. Also the pelvic floor may be weaker and, over time, may result in incontinence.
One thing that is important to note is that people with neurogenic bladders commonly use intermittent catheterization to vacate the bladder. For those in wheelchairs, the ureter is more accessible for men than it is for women. Anatomic considerations are very important when assessing the management of the lower urinary tract.
A very important part of the lower urinary tract is the neural control. The control mechanism starts in the brain, goes down through the spinal cord and enervates the bladder and the urethra. The brain is where people are aware of their bladder filling and sends signals for the bladder to voluntarily vacate. If there is a problem with either the brain of the spinal cord, the communication system may not be working so well. There are different centres in the brain that control bladder function. There are also different centers along the spinal cord that control bladder function; one is very close to the brain, one is very high up in the back and the third is very low down in the back. All of these centres must be working together to have normal bladder function. If there is a problem with any part of the system, there may not be normal bladder function. Normal bladder function is determined by the anatomy and the neural control.
In spina bifida, there is an abnormality in the development of the canal around the spinal cord and also in the nerves themselves. The peripheral nerves, that is the extension of the spinal cord that actually goes to the end organs - in this case the bladder and the urethra, maybe abnormal and the communication or the nerve supply may not be normal, resulting in a problem with function of the bladder, the urethra and the urinary passage.
How does the normal bladder work? It consists of two phases and is all intuitive. There is the storing phase and the emptying phase. The bladder is a reservoir; it drains the urine from the kidneys and over time, the bladder fills. Normally, one is not aware that your bladder is filling. While the bladder is filling, the urethra or the control mechanisms around the urinary passage are tightened up. When the bladder is full, usually between 200 and 500 c.c.s, you get the sensation that you have to go to the bathroom. At this time, your brain allows the urethra to release and tells the bladder to squeeze, much like a balloon squeezing. After the bladder is empty, the process starts again. A neurogenic bladder results when any of the nerves that control communication between the brain and the bladder are affected.
In people with spina bifida, the neurologic defect produced is variable and cannot be totally predicted by the reticule level. We know that there are different nerves that come at different levels in the spinal cord and by knowing the anatomic abnormality, usually one can predict what type of problem there is. In the bladder, it doesn't always happen as expected. There may appear to be a problem, sometimes nerves will be fine. In general, the incidence of bladder and urethral dysfunction is not known. We can't predict how many people will have a problem with their bladder, however most studies suggest the number to be very high.
In a neurogenic bladder, the storage and emptying phases are not totally under control. The bladder may be described by different terms: underactive (it doesn't work at all), normal (quiescent when it fills and squeezes normally when it's time to empty) or overactive (it goes into spasm and does not allow much urine to enter). At the same time, we can look at the urinary passage or urethra to see if it is underactive (which may have a problem with control), normal (remains tight when the bladder is filling and relaxes when the bladder is emptying) or overactive (it does not relax when the bladder is trying to work). There are multiple combinations of patterns that can occur.
The general problems that we see are: urinary retention (the inability to empty the bladder), incontinence (the inability to stay dry) or both. To assess the problem, the physician must take a history of what's bothering the patient and do a physical examination. A laboratory test can also be done to determine if there is a urinary infection or blood tests to determine if there is kidney dysfunction. There are additional tests which can; a cystoscopy, imaging studies, urodynamic studies and ultrasound.
People with neurogenic bladders may suffer from hydronephrosis or swelling of the kidneys. Hydronephrosis can result from the pressure in the bladder being to high to allow the kidneys to drain. This can ultimately cause the kidneys to fail.
Cystoscopies are performed if there is a urinary tract infection, retention or the inability to empty the bladder. A cystoscope is a flexible telescope that inserted into the urinary passage to examine the bladder.
Urodynamics is a test which measures how the bladder and the urethra are working during the filling and voiding phases. A number of catheters are placed inside the bladder and the bladder is slowly filled. The catheters are connected to a machine which registers how the bladder handles the filling and voiding phases. This test will also determine the pressure in the bladder. If the bladder pressure is too high, it will result in reflux in which case the urine from the bladder is forced back into the kidneys.
Catheters may also be used to fill the bladder with x-ray contrast medium which would give a picture of the bladder in an x-ray. This is called a cystograph.
How do we manage people with neurogenic bladders? The most important issue is to preserve renal function; to keep the kidneys functioning. The second issue is to control incontinence. We must also take in to account social flexibility, that is what can the patient do that is reasonable to manage their situation. We must also consider what is most cost effective for the patient.
The most common problem in people with spina bifida is the inability to empty the bladder and the most common method to treat this is intermittent catheterization. Stimulated voiding is used when the patient has the ability to empty their bladder and may be used in combination with intermittent catheterization. New devices which are surgically implanted and allow the bladder to act normally do not work well with neurological bladders.
Urinary incontinence may be aided by bladder training, but more important is bowel management. There are medicines that can aid in incontinence, and, if all else fails, there are surgical procedures which can offer relief. Frequently, combinations of several treatments are used to achieve regular bladder control.
Urinary incontinence is defined as the complaint of any involuntary release of urine. It is very common and can affect people without neurological bladders. Stress incontinence is caused by the weight or pressure in the tummy putting pressure on the bladder; for example, if you sneeze and release urine. Urgency incontinence is feeling the need to relieve yourself but not making it to the bathroom in time. It is believed that this may be due to an overactive bladder. Mixed incontinence is a combination of stress and urgency incontinence. In the non-neurologic population, stress and urgency make up approximately 90% of the cases seen.
There are other types of incontinence commonly seen. Overflow incontinence is caused by retention. The bladder fills and cannot hold the urine. This is common in a neurological bladder. Functional incontinence is commonly seen in older people. There is a problem outside the urinary tract, for example the patient has a sore leg and cannot get to the bathroom in time. Unconscious incontinence means the patient is not aware that they are leaking urine. This may refer to people with neurological diseases. There is also incontinence caused by surgical procedures.
There are several general health practices which can aid in urinary incontinence. Caffeine should be avoided as it is a diuretic. Smoking may cause coughing which may lead to stress incontinence. Regular bowel maintenance assists in putting less pressure on the bladder. Weight management is important as excess weight puts stress on the bladder. Pelvic strengthening may help relieve incontinence.
Medications are commonly used to affect the bladder when it is overactive by keeping it more relaxed. There is an antidepressant which has a side effect of relaxing the bladder and tightening the urethra.
If the urinary passage is weak, we resort to interventional treatments. One treatment is injecting collagen into the lining of the wall of the urinary passage in order to make it close a little tighter. The injections are costly and do not work for long periods of time, so they must be repeated. The injection is covered by OHIP, however the drug injected is not.
There are some surgical procedures which can tighten the urethra; some are simple, some are complex. Most of the surgical procedures for women are simple and can be done on an outpatient basis. For men, unfortunately, the procedure is much more complex. The typical procedure is the insertion of a artificial sphincter, which is a pump inserted in the groin.
If there is a problem with the bladder and it does not respond to medications, the physician may recommend an augmentation cystoplasty. A segment of the intestine is removed and refashioned as a sphere and added to the bladder.
Occasionally, there may be difficulty in reaching the urethra, particularly in women who use a wheelchair. In these instances, an opening is created from the bladder to the stomach wall. This is called a Mitrofanof, named after the French physician who invented it. Part of the bowel is taken from the bladder to the stomach wall to create an opening that can be used for catheterization.
There are risks and complications to the augmentation surgery. There can be an affect on the patients overall health, affecting the metabolic functions. There may be bladder stones or, in some cases, the bladder may rupture. There is also a concern of the development of bladder cancer. As well, the procedure may fail overtime and may need to be supplemented with medications or even re-augmented.
If every option has been tried and there is still a problem with the kidneys, the bladder is unable to be fixed or the urinary passage is too weak, a urinary diversion is performed. A small piece of the intestine, approximately 8 to 10 inches, is segregated and brought up to the skin. The ureters are connected to it so that the urine flows into the pouch. An exterior bag is worn to collect the urine. This is called an ileal conduit.
Another option is to use part of the intestine to create a new bladder, part of which is brought up to the skin. The ureters are connected to it and the patient would catheterize through an opening in the stomach. This is called an Indiana pouch.
Urinary continence also has bearing on sexual function. Sexual function consists of desire, erection, orgasm and ejaculation. The erection is brought on by touch or thinking. Approximately 75% of men with spina bifida can achieve an erection, usually by direct stimulation rather than thought or pyschogenic stimulation. During the sexual act, the sperm travel through a small tube from the testicles, through the prostate gland, up through the urinary passage and through the penis. At this time, the neck of the bladder closes tightly. In men with spina bifida, the neck to the bladder is often very weak and there may be a return of fluid into the bladder. This is called retrograde or absent ejaculation. It is very common although the total number is unknown. There are a number of medicines and surgical procedures to assist a man achieve an erection. Women with spina bifida can usually become pregnant and should be aware of contraception.
In conclusion, spina bifida usually results in neurological bladder problems. The management must be individualized. Evaluation and treatment are necessary to maintain kidney function and also to improve and maintain the quality of life. As the neurogenic bladder determines how the kidneys function, it is necessary to maintain lifelong follow-up.
Question from the floor - Are you currently involved in research into bladder management and sexual function? Dr. Herschorn - One of the new techniques for stress incontinence can easily be applied to people with spina bifida or a neurogenic bladder. New medications and drugs are now being applied to people with spina bifida or a neurological bladder. Botox is being looked at specifically for overactive bladders, as an additional therapy. There is some research on electrical control devices for people with spina bifida, however there is not much of this in Canada. One of the exciting things on the horizon in urology is regenerative medicine, which involves organ substitutes. In the case of the bladder, it would be something to maintain or recreate bladder function, but not the intestine.