Urology and UrodynamicsMedical professionals specialising in the field of urology are called urologists and are trained to diagnose, treat, and manage patients with urological disorders.

Urology is the branch of medicine that focuses on the urinary tracts of males and females, and on the reproductive system of males.
This branch of medical science deals mainly with diseases of Kidney, Urinary bladder, Prostate gland, Testis and Penis.
It deals with diseases such as; Urinary tract infections, Male sexual dysfunction and male infertility.
It also deals with the tumors of Kidney, Ureter, Bladder, Prostate, Testis and Penis.
Congenital anomalies of the Genitourinary tract like pelvic ureteric junction obstructions, vesico ureteric reflux, posterior urethral valves etc. are all taken care of. Additionally, various voiding dysfunctions are also treated under this speciality.

In men, the urinary system overlaps with the reproductive system, and in women the urinary tract opens into the vulva. In both sexes, the urinary and reproductive tracts are close together, and disorders of one often affect the other. Urology combines management of medical (i.e., non-surgical) problems such as urinary infections, and surgical problems such as the correction of congenital abnormalities and the surgical management of cancers. Such abnormalities within the genital region are called genitourinary disorders.
Urology is closely related to, and in some cases overlaps with, the medical fields of nephrology, andrology, gynecology, proctology and oncology.

 

Urodynamics

Urodynamics is the investigation of the function and dysfunction of the lower urinary tract. Urine produced in the kidneys is transported to the bladder by rhythmical contractions of the ureters. At appropriate occasions the bladder is emptied via the urethra by contraction of the normally relaxed detrusor muscle that constitutes the wall of the urinary bladder. Urinary incontinence is a problem that affects a large number of people. Many women suffer leakage of urine when they cough or sneeze (a problem known as stress incontinence), and it is common for older men to suffer problems such as poor stream. The detrusor muscle's behaviour is thought to sometimes become 'unstable', leading to the lower urinary tract symptoms such as problems with frequency, urgency and getting up at night to pass urine. An unstable detrusor also contracts between voidings. This causes high pressures in the bladder that may be felt as urgency and give rise to urine leakage.

In men, many of these same symptoms can be caused by enlargement of the prostate gland (Benign Prostatic Hyperplasia) and urodynamic studies can help to differentiate the two causes.
For obstruction the International Continence Society has agreed that presently the only way to objectively diagnose it and/or grade its severity is a urodynamic pressure-flow study.

For incontinence the issue is more complicated.

There are two main types of incontinence:

  • Stress incontinence, which is caused by a deficiency of the closure mechanism of the bladder.
  • Urge incontinence, which is caused by over-activity of the bladder. This over-activity can be demonstrated urodynamically.

Clinically, the difficulty is that it is generally not possible to determine the causes of these problems purely on the basis of symptoms and medical history. Urine produced in the kidneys is transported to the bladder by peristaltic contractions of the ureters. At appropriate occasions the bladder is emptied via the urethra by contraction of the detrusor muscle in the bladder wall. In the medical speciality called urology, diseases of the male and female urinary tract and of the male sexual organs are diagnosed and treated. In urodynamics, diagnostic methods based on measurement of physical quantities such as pressure and flow-rate are developed and applied to the urinary tract. Urodynamics testing is often used to try and find out what is causing bladder problems. The test is used when a bladder problem occurs which is difficult to diagnose or the patient may already have a diagnosis, but the doctor needs more information on the extent of their condition. It could also be that the doctor is thinking about surgery, and the test can make sure the operation will help.

 

The Test

Urinary tractThe test measures how long it takes to empty the bladder, and whether the flow of urine is even, or if it stops and starts. It measures the way the bladder contracts to start the flow of urine, and how much pressure there is in the bladder and urethra (the tube that carries urine out of the bladder). It usually takes about an hour and a half to complete.

No one can pretend that urodynamics is a pleasant procedure. In good clinics, staff do their best to put the patient at ease and make sure they are treated sensitively. Over a number of years, a system has been developed using a computer-based urodynamics measuring technique, which simplifies the process of acquiring the pressure and flow measurements, and to present and store the resulting information in an easily used way. A fine tube, called a catheter, is inserted into the bladder - through the opening in the tip of the penis in men, and in the small opening above the vagina in women. A second very fine catheter is inserted at the same time. This is not painful, though it may be a bit uncomfortable.

The patient will also have a third catheter inserted into their rectum. In a urodynamics study, two pressures are measured. The pressure within the bladder is measured via urethral catheter, and the pressure in the abdomen is measured via a second catheter inserted in the rectum. The detrusor pressure is the difference between these two measurements.


The examination comprises two main phases.
In the first, the patients bladder is filled with fluid (saline) at a controlled rate; in the second, the patient voids, and the volume of urine voided is measured. Filling is carried out using a peristaltic pump, which is controlled to deliver fluid at a known rate. The volume voided is measured by weighing the urine on a specially esigned electronic balance; the volume signal is also differentiated with respect to time to give a flow rate signal.

Once the bladder is full the patient will be asked to stand and cough, and then to pass urine into a commode. The commode has a flow-meter inside it, again linked up with a machine, which prints out the result. They should be able to do this entire procedure in private. The catheters are taken out as soon as the test is over. In some clinics the patient may be given an X-ray which records what is happening on film. The patient lies down, and the X-ray machine is positioned above your bladder. The report of these tests is then sent to the doctor investigating the bladder condition.

Urology equipmentThe overall system comprises two main parts: the controlling computer, which is usually a standard PC compatible machine, and an instrumented commode, containing the sensors and associated electronics.

The instrumentation in the commode comprises isolated amplifiers for the two pressure transducers, for patient safety, the electronics associated with the balance used to weigh the voided urine, and a controller for the filling pump. These are all controlled by an embedded microcomputer, which acquires and buffers the sensor signals and controls the communications link to the host PC.

At regular intervals, the PC transmits a request to the commode for a packet of data. The commode unit responds by sending its latest frame of data, which the PC then processes. The processed data is plotted on the PC screen, and stored on disk. The stored data can then be plotted on paper, as part of a formatted report. Additionally, the data is stored in a format that facilitates importing it into a separate spreadsheet package.

 

Sources:

http://www.sghurol.demon.co.uk/urod/
http://en.wikipedia.org/wiki/Urology
http://mewarhospitals.com/service/urology/

 

Edited by Dr. John Sandham