Hypothesis / aims of study
Video urodynamics allow for correlation of lower urinary tract anatomy with physiology during the filling and voiding phases – and enable more precise delineation of site and cause of bladder outlet obstruction and/or incontinence as well as additional findings such as vesico-ureteric reflux at the expense of radiation exposure. We have assessed whether clinician related factors affect the total radiation exposure time (RET, an operator controlled component that affects total radiation dose) and the actual radiation dose (RD) during video urodynamics.
Study design, materials and methods
The radiation exposure time and radiation dose of all 986 consecutive patients having video urodynamics to investigate refractory lower urinary tract symptoms between 13/01/2018 and 31/01/2019 were retrospectively reviewed from our Radiology Information System database. 208 (31.2%) patients were excluded owing to: missing information fields, failure to complete video urodynamics due to patient or equipment factors and owing to additional simultaneous tests that further exposed patients to radiation such as the retrograde leak point pressure test.
Clinical Scientists and training Urologists used a standardised Female, Functional and Restorative (FFR) Urology protocol when performing the video urodynamics whilst the other groups did not.
Total radiation exposure time and total radiation dose were determined and correlated with speciality and grade of clinician performing the test. Statistical analysis was by Kruskal-Wallis with pairwise multiple comparisons by Dunn’s test. Statistical significance was determined at P < 0.001.
Interpretation of results
There is wide variation in total radiation exposure time (median=38s, range=247s) and hence radiation dose (median=151cGy.cm², range=345cGy.cm²) during video urodynamics. Clinical Scientists and Urologists in training have significantly lower radiation exposure times and radiation doses whilst Consultants, in particular Radiology Consultants, have significantly longer exposure times for the same diagnostic yields. A further sub analysis of patients that underwent video urodynamics on the same fluoroscopy unit that were either on the radiology or gynaecology pathway (i.e. non-FFR) revealed similar findings - with Consultant Radiologists and Gynaecologists delivering near double the radiation exposure times and over double the radiation dose compared to the Clinical Scientists.