Sterile water or saline are commonly used fluid media to fill the bladder during an urodynamics study. It may be cost effective to use 500 mL bags of fluid as functional bladder capacity usually does not exceed this volume. When assessing for incontinence without fluoroscopy, it can be useful to add indigo carmine or methylene blue to the fluid so that leakage can be readily identified during the study. If fluoroscopy is used for video-urodynamics, it is necessary to use radiographic contrast as the fluid media.

During voiding, intraurethral pressure decreases prior to the detrusor contracting and this, in turn, is related to pelvic floor relaxation [4]. Franksson and Peterson are credited with EMG studies of the pelvic floor and form the basis for incorporation of EMG into UDS tests [10]. EMG is particularly useful in the diagnosis of functional obstruction and can be performed with surface, needle, intravaginal, or rectal electrodes. Widespread use of surface EMG is likely driven by technical ease and patient comfort. Examples of intravesical and intraabdominal catheters and surface EMG electrodes are shown in Fig. 1.2.

Uroflowmetry is the measurement of the rate of flow of urine over time, typically reported in milliliters per second [1]. As the essence of UDS is the ability to determine the relationship between bladder pressure and urine flow rate, most UDS systems include a uroflowmetry device although a graduated beaker to collect urine and a uroflow meter stand are usually not included with the UDS system.

It is often overlooked that the uroflow meter purchased with a UDS system can be used alone when only uroflowmetry is desired. This can potentially result in cost and space savings by obviating the need for both a urodynamics machine and a separate uroflow meter .

A multi-positional exam table controlled by a foot pedal is the most advantageous as it allows the patient to be seamlessly repositioned during the study from the supine or lithotomy position for catheter placement to a seated position for the study.

When video-UDS is being performed, a radiolucent exam table or commode chair must be used if the study is performed supine or in the sitting position, respectively. An alternative to using a radiolucent exam table or commode is performing the study in a standing position.

In recent years, wireless UDS systems have become available such that information obtained from the pressure transducers and uroflow meter is wirelessly transmitted to the computer. Values for intravesical and intraabdominal pressure, volume infused, uroflowmetry, volume voided, and UPP are uploaded without a direct connection to the computer. The most obvious advantage of a wireless system is having fewer cables. In addition, these systems also have a smaller footprint and provide greater flexibility in terms of equipment setup, as computer proximity to the UDS machine is not dictated by cable length.

Available software that is compatible with certain UDS systems is an important consideration when purchasing equipment. Some of the software options are graphical appearance of the study, layout options for reporting patient history and study data, nomograms, and computerized interpretation of the study. When acquiring a UDS machine, options and cost for software upgrades should also be considered.

Once UDS data are acquired, the computer hard drive is able to store the results, but most clinicians also want the data in each patient’s medical record. Options of data transfer to a patient’s medical record are either (1) print a hard copy of the study to either place in a patient’s paper chart or scan into an electronic chart or (2) have the electronic data directly sent into the patient’s electronic medical record (EMR) .

When acquiring a UDS system, a printer is often included. If not, the compatibility of a printer with the UDS system must be determined. With multichannel UDS, each channel may be assigned a different color for ease of interpretation; however, the cost of color ink is an additional consideration.

For clinicians who have an existing EMR, compatibility of UDS software must also be considered, as there are significant advantages of direct data transfer. Both time and cost of printing a report are avoided, and the UDS data can be stored both in the UDS system hard drive as well as in the EMR. Engineers from both the UDS equipment manufacturer as well as the EMR vendor are usually necessary to establish a direct link between the UDS machine and the EMR. Examples of software currently available are listed in Table 1.1.

Video-urodynamics is the addition of a voiding cystourethrogram to the pressure-flow study. The most commonly applied imaging is fluoroscopy. In the past fluoroscopy units were often large and extremely expensive, but modern units are mobile and with a relatively small footprint such that video-UDS can be performed in the office. The cost of a fluoroscopy unit may be offset by using it for purposes other than video-UDS. In addition to video-UDS, the authors use their fluoroscopy unit for cystograms, retrograde urethrograms, evaluation of stones or stent position, nephrostograms, and percutaneous sacral nerve evaluation trials.

Safety requirements for fluoroscopy vary by region, but items to consider include physician fluoroscopy licensing (and any other medical personnel who will be operating the fluoroscopy machine), state registration of the fluoroscopy machine, evaluation of the machine by a radiation physicist, lead lining of the examination room, and protective shielding for the clinician and patient. The radiology licenses also need to be posted in the room where the imaging will be performed. Furthermore, radiation badges must be maintained and submitted for regular monitoring .