Hydrodistention of the bladder is a procedure frequently performed to help establish a diagnosis of interstitial cystitis. Hydrodistention literally means to distend the bladder with water. Water (saline or a glycine solution may also be used) is instilled into the bladder to a relatively high pressure (80-100 cm H20). When the water is released from the bladder, patients with interstitial cystitis typically develop small bleeding points under the bladder surface, termed "glomerulations." The procedure is usually performed under general or spinal anesthesia since most patients cannot tolerate the discomfort of bladder filling. Filling of the bladder is performed through a cystoscope. The cystoscope is inserted into the urethra, the tube allows urine to pass out of your body.
The anesthetic bladder capacity, how much your bladder can hold at that pressure, is usually lower than normal (usually less than 800cc) in most patients with interstitial cystitis. Minute tears of the bladder's inner lining may also be seen.
A bladder biopsy may be taken, particularly if any abnormal areas of the bladder wall are seen. The biopsy is performed directly through the cystoscope. The amount of tissue taken is about the size of this "O." On occasion, several biopsies are obtained. The biopsies are usually assessed for the presence of inflammation and/or cancer.
Hydrodistention may also be used for therapy as about 30% of patients will have some symptom relief. In general, hydrodistention is not used very frequently in my practice for symptom relief due to the relatively low success rate, the invasiveness of the procedure and the ultimate return of symptoms in most patients.