Video urodynamics

Summary The simultaneous recording of urodynamic parameters and x-ray imaging of the lower urinary tract is the ideal technique for a complex investigation of lower urinary tract function and x-ray morphology. To minimize pain-artefacts by tubes and electrodes, the preparatory measurements, which include the suprapubic insertion of two tubes into the bladder, are done the day before, if necessary, in a short general anaesthesia, the investigation itself is performed the following day without an irritating catheter in the urethra and without pains for the patient (which is especially essential when investigating children). The technical details of a modern videourodynamic system and its advantages for this type of investigation are presented. However, the clinical practice has also revealed some weak points of the system, which need to be improved. The technique together with modern technology guarantees accurate and reproducable information also in childeren.     

Video urodynamics using transrectal ultrasonography for lower urinary tract symptoms in women

AIMS: To understand the properties of lower urinary tract disorders in women, we evaluated 60 female patients with lower urinary tract disorders or symptoms of recurrent cystitis by free uroflowmetry and video urodynamics using transrectal ultrasonography (VU-TRUS). METHODS: Results of urodynamic studies or symptoms of stress incontinence were used to divide 60 women into 7 normal controls and 53 with voiding dysfunctions. RESULTS: In normal controls, VU-TRUS showed that the mean posterior urethrovesical angle and anteroposterior diameter of the proximal urethra at maximum flow was 151.4 degrees and 4.9 mm, respectively. In patients with voiding dysfunction, VU-TRUS during voiding revealed various urethral abnormalities, including 16 detrusor sphincter dyssynergia, 4 detrusor bladder neck dyssynergia, and 13 insufficient opening of the entire urethra. VU-TRUS also showed pelvic floor abnormalities, including 24 urethral hypermobilities (group 1) and 11 cystoceles (group 2). Eighteen patients had neither urethral hypermobility nor cystocele (group 3). Major pressure-flow abnormalities in the 53 patients with voiding dysfunctions were weak detrusor (72%) and/or bladder outlet obstruction (25%). There were no significant differences in the distribution of the pressure-flow abnormalities among the three groups. However, the mean values of abdominal pressure at maximum flow of group 1 (20.9 cm H(2)O) and group 2 (17.9 cm H(2)O) were significantly higher than that of group 3 (6.3 cm H(2)O; each P < 0.05). The mean values of residual urine volume of group 2 (60.8 mL) and group 3 (77.6 mL) were significantly higher than that of group 1 (23.5 mL; each P < 0.05). CONCLUSIONS: The symptoms of women with lower urinary tract disorders were frequently accompanied by urethral and/or pelvic floor abnormalities during voiding that were clearly detected by VU-TRUS. VU-TRUS is useful for objective evaluation of female lower urinary tract symptoms.     

Office urodynamics

Each urologist can best form his or her own set of indications for and techniques of urodynamic evaluation or referral. Thus, what constitutes "office urodynamics" in one practice does not in another. The practicing urologist should at least have access to filling cystometry, flowmetry, residual urine determination, and voiding cystourethrography. All but the last named are certainly compatible with any office practice.     

Ambulatory urodynamics

Long-term ambulatory urodynamic monitoring has been employed in 20 patients in an attempt to detect detrusor abnormality not appreciated by conventional cystometry. In 9 female patients with the "urge syndrome" it detected 2 previously unrecognised cases of detrusor instability; in 4 enuretic patients, only 1 of whom was known to be unstable previously, unstable contractions were confirmed, and 2 of 7 cystoplasty patients had high amplitude contractions detected only on ambulatory assessment. The technique provides a more sensitive index of lower urinary tract function than conventional cystometry in such patients.     

Computer-assisted urodynamics

We have assembled a computer hardware system and have written software programs that convert analogue urodynamic input to digital data. This has allowed for 1) extremely accurate recording of urodynamic events with a higher frequency response than existing units, 2) data storage of urodynamic events in digital form on floppy disks, 3) retrieval and plotting of urodynamic studies during and at times remote from the study performance, and 4) manipulation of the parameters in the urodynamic study for patient care and research purposes. Software is now available for the performance of cystometrograms (volume, total pressure, intravesical pressure and dP/dt), electromyograms, flow studies and dynamic renal pelvic pressure testing. Programs are in the development phase for computer analysis of urodynamic studies.     

Pitfalls of urodynamics

Increased interest and use of urodynamic testing have led many clinicians to rely on the results for patient care. Numerous shortcomings and possible sources of error have been identified. Well trained personnel, properly structured examination rooms and understanding of the potential pitfalls in urodynamics are essential to proper medical management of patients with micturition problems.     

Ultrasound in urodynamics

Recent developments of ultrasound imaging have contributed much to the understanding of urodynamics in patients with lower urinary tract symptoms (LUTS). These include ultrasound estimated bladder weight (UEBW), transrectal power Doppler imaging of the prostate and transrectal ultrasonography during voiding (voiding TRUS). UEBW, which is obtained by measuring the thickness of the anterior bladder wall using a 7.5 MHz probe, represents well the degree of bladder hypertrophy caused by obstruction. This parameter is, accordingly, of clinical use in the evaluation of obstruction. The UEBW predicted the presence of obstruction as determined by pressure-flow study with a diagnostic accuracy of 73%. Transrectal power Doppler imaging of the prostate has made it easy to detect prostatic vessels and furthermore to obtain their resistive index (RI). Accumulating data suggest strongly that RI reflects the intraprostatic pressure. More interestingly, RI decreases significantly during voiding in normal subjects but not in patients with benign prostatic hyperplasia. Thus, this method is of particular use in monitoring noninvasively the dynamic change in intraprostatic pressure during voiding. Voiding TRUS makes it possible to monitor the movement of not only the posterior urethra but also the prostate during voiding. Based on our recent study, the anterior fibromuscular stroma (AFMS) seems to contract to open the urethra. Although the physiological function of the AFMS in the prostate remains unknown, AFMS may play a significant role in normal micturition. Due to its noninvasiveness and ease of application, ultrasound imaging would play a vital role in the diagnostic process for patients with LUTS in future.     

Transrectal ultrasound urodynamics

Seventy-seven male patients (34 with cervical spine injury, 32 with thoracic spine injury, 9 with lumbosacral spine injury, and 2 with multiple sclerosis) who were referred to our spinal cord injury unit for urologic evaluation had videourodynamic studies using transrectal ultrasound and fluoroscopy. All were studied twice in the same session: first with transrectal ultrasound urodynamics (TRUSU) and the second time with conventional fluoroscopic videourodynamics (VUD). The findings were compared. Efficacy of TRUSU: (1) clearly documented flow of fluid through bladder neck into posterior urethra before clinical leakage occurred per urethra; (2) allowed accurate placement of EMG needle electrodes in external urinary sphincter under visual guidance; (3) provided high-quality imaging of surrounding structures and allowed assessment of bladder neck, prostate, seminal vesicles, and posterior urethra; (4) eliminated radiation exposure to the patient and the examiner, with no time limit imposed on imaging so that repeat studies could be done to evaluate patients on new drug treatments or postoperatively at no increased risks; and (5) its availability to most urologists at their office at considerably less cost to set up than fluoroscopy. In our study TRUSU identified a hypoechoic lesion in the prostate of 1 patient and a tumor in the bladder neck of another patient. Fluoroscopic VUD identified 6 patients with bladder diverticula and 2 with grades 1 and 2 vesicoureteral reflux which TRUSU did not identify. Our experience indicates TRUSU is a valid and preferable alternative to fluoroscopic VUD for patients with spinal cord injury.     

Caliceal urodynamics.

In this study the author emphasizes the existence of a muscular element that had not been described until now. This muscular element is situated around Malpighi's pyramid and its fibres are followed by the caliceal muscle and the elements that form Henle's peripapillar ring. The systolic and diastolic function of this peripyramidal muscle can be observed in the urographies, during the evacuation of the collector tubules of Bellini, and its synchronization with the next caliceal and pyelic musculature.     

Morbidity after ambulatory urodynamics

AIMS: To identify urinary symptoms and morbidity after ambulatory urodynamics. METHODS: One hundred consecutive women underwent ambulatory urodynamics for a variety of urinary complaints. Urinary symptom questionnaires were collected before investigation and again 48 hours later, reporting dysuria and haematuria. Women were screened for urinary tract infection before investigation and again 48 hours later. RESULTS: Of the 91 women who completed the study, 1 (1.1%) had a positive urinary culture after the investigation but was asymptomatic. Seventeen women reported mild to moderate de novo dysuria. CONCLUSIONS: Urinary symptoms and morbidity after ambulatory monitoring is low.     

Urinary incontinence and urodynamics

Incontinence can be the result of impaired functioning of the detrusor muscle and/or the sphincter mechanism. For this reason, the pathomorphology and the pathophysiology should be documented before surgery, so that if it is not successful it is possible to deduce what alterations have been caused by an operation and the reason why the treatment has not been successful. Vaginal reconstruction of the pelvic floor following vaginal prolapse is a safe, effective surgical procedure, particularly for older women. Abdominal fixation of the vaginal stump through open or laparoscopic sacrocolpopexy gives long-lasting and anatomically favourable results especially for younger women who are sexually active, but is associated with a higher mortality rate. Incontinence treatment in men is itself gradually becoming accepted as a subspecialty. Pharmacological treatment that is used for urge incontinence takes the form of substances that relax or desensitize the detrusor (antimuscarinics, oestrogens, alpha-blockers, beta-mimetics, botulinum toxin A, resiniferatoxin, vinpocetin), while stress incontinence requires stimulation of the sphincter and pelvic floor (alpha-mimetics, oestrogens, duloxetin). Bladder function disturbances in children can be classified by noninvasive methods, but the therapy remains a difficult endurance test for the children, their parents and the doctor, often extending over years.     

Outcomes and obstacles of urodynamics

Urodynamic testing provides information on bladder function and bladder outlet and sphincteric competence. The author explains when patients should be referred and provides some insight into these tests.