Artefacts in Urodynamics

The importance of discerning fact from artefact is a fundamental requirement of urodynamics; it is crucial for understanding the patient's lower urinary tract function and avoiding spurious conclusions that could have very bad consequences if they lead to inappropriate treatment. Measurement artefacts are produced by problems in the equipment, somewhere between the tip of the catheters and the display. An obvious artefact is caused by the patient moving their stream in relation to the central exit from the collecting funnel. This is usually a male patient since the penis enables him to steer the stream around the funnel. Some men have the habit of squeezing the urethra, or the tip of their penis or foreskin during voiding with a gentle pinch grip that occludes the lumen. Rectal contractions are more likely in people with neurological disease and anyone with a loaded rectum from constipation.