Radiation exposure during videourodynamics in women

What do X-ray images of the bladder during video urodynamics show us in patients with spinal cord injury?

STUDY DESIGN

Retrospective anonymized cohort study.

OBJECTIVES

To study X-ray images of video urodynamics (VUD) in patients with spinal cord injury (SCI).

SETTING

Single-center study.

METHODS

X-ray images during VUD were categorized. Relation with the American Spinal Injury Association Impairment Scale (AIS), time since and level of SCI, cystometric data, method of bladder management, findings of flexible cystoscopy, and renal ultrasound were evaluated. Changes over time were studied.

RESULTS

In 231 consecutive patients, VUD was done at a mean of 8.5 years after SCI. X3-ray bladder appearance was categorized as normal/standard, tonic, or flaccid. In 19 patients, specific findings were seen: diverticula, cystocele, vesicoureteral reflux. X-ray images differed by maximum cystometric capacity, presence of neurogenic detrusor overactivity, and maximum detrusor pressure during detrusor overactivity, but not by bladder compliance. There was no difference in the categories found in different levels and completeness of SCI. In the 23 patients able to void no pathology was seen on urethral images. Renal ultrasound was normal in >99%. In 86 patients, repeated testing after 72 ± 143 weeks showed changed findings in 30%. Cystoscopy showed significantly more local pathologies.

CONCLUSION

Complications in the lower urinary tract were seen on imaging only in a limited number of our cohort. As our findings represent a real-life example of the actual yield of VUD in patients with neurogenic bladder due to SCI treated following the international guidelines, further multicentre evaluation is needed to determine when imaging should be used or not.

Evaluation of bladder shape using transabdominal ultrasound: Feasibility of a novel approach for the detection of involuntary detrusor contractions

Conventional assessment of overactive bladder syndrome uses invasive pressure-measuring catheters to detect bladder contractions (urodynamics). We hypothesised that bladder shape changes detected and measured using transabdominal ultrasound scan could provide a non-invasive and clinically useful alternative investigation of bladder contractions. This feasibility study evaluated a novel transabdominal ultrasound scan bladder shape test during conventional urodynamics and physiological bladder filling. The aim was to initially evaluate and refine a non-invasive approach for detecting and quantifying bladder shape changes associated with involuntary bladder contractions. To develop measurement techniques and characterise bladder shape changes during bladder filling, healthy female volunteers (n=20) and women with overactive bladder symptoms who had previously undergone urodynamics (n=30) completed symptom questionnaires and bladder diaries. The bladder shape test protocol included consumption of 1 l water before undergoing serial transabdominal ultrasound scan imaging of the bladder during physiological bladder filling and during episodes of urgency. In a further group of women with overactive bladder (n=22), serial transabdominal ultrasound scan images were captured during urodynamics so that shape changes occurring with bladder contractions could be characterised. In both healthy volunteers and women with overactive bladder, the transverse view of the bladder provided the most reliable plane to characterise and measure bladder shape changes. A sphericity index derived from the ratio between maximum inscribed and minimum circumscribed ellipses (πac^2(inner)/πac^2(outer)) offered a reliable and reproducible measurement system. Of participants undergoing transabdominal ultrasound scan during urodynamics, there were significant measurable differences in sphericity index between patients with bladder contractions (n=12) and patients with acontractile bladders (p < 0.001). Bladder shape changes detected during physiological filling and urodynamics have provided preliminary evidence to support further research into bladder shape test as a non-invasive diagnostic tool to identify involuntary bladder contractions in patients with overactive bladder syndrome.

Basics of videourodynamics for adult patients with lower urinary tract dysfunction

AIMS

Videourodynamics is the addition of imaging to invasive urodynamics and one of the methods to ensure objective diagnosis in persons with signs or symptoms of lower urinary tract dysfunction. This manuscript has the aim to outline the basics of the practice of videourodynamics and to elementary explain interpretation of the results.

METHODS

Literature sources and expert opinion were arranged to provide the reader with an introductory overview of current knowledge.

RESULTS

Videourodynamics was-like most diagnostics in health care-introduced on the basis of plausibility and expert conviction but has stood the test of time. Videourodynamics has, especially in patients with congenital or acquired neurogenic dysfunction of the lower urinary tract, undisputedly although not precisely quantifiable, added to (lower urinary tract) health care quality.

CONCLUSION

The manuscript summarizes the basic elements of indication, practice, and interpretation of videourodynamics.

Can we replace the catheter when evaluating urinary residuals?

AIMS

To test the different formulae to calculate the bladder volume using ultrasound; the accuracy of patients hearing/feeling "bubbles" at the end of urodynamics testing as a measure of being empty; and how good we are at estimating PVR using X-ray at the end of video urodynamics testing.

METHODS

This was a prospective cohort study. Using Sonosite 180 plus, bladder volumes were calculated as, height × width × depth × proportionality constant (0.52, 0.625, 0.65, and 0.7) Patients were asked whether the patient heard or felt "bubbles" at the end of the investigation. Each patient was fluoroscopically screened and the clinician estimated the volume and compared with single-use catheter volume.

RESULTS

A total of 85 patients were assessed. All four formulae were significantly correlated. The PC, 0.52, correlated best (r = 0.938, P < 0.001) with no significant difference with the actual volumes ( P = 0.275). The "bubbles test" had a positive predictive value of 93%. A video postvoid residual (PVR) estimation significantly correlated with catheterised bladder volume ( r = 0.842, P < 0.001). There was no significant difference between the estimated and actual bladder volumes ( P = 0.579).

CONCLUSION

This study showed that although all four formulae correlated significantly, the PC of 0.52 was the only formula without a significant difference from the actual volume. More work is needed to produce patient individualised PC. Our clinicians were able to accurately estimate the PVR on X-ray. This study has identified the best formula to accurately estimate bladder volume and that video estimation along with the "bubbles" test can avoid unnecessary intervention.

Fluoro-urodynamic Image Interpretation Is Not Altered by Using Dilute Intravesical Contrast

OBJECTIVE

To determine if using one 250 mL bottle of intravesical contrast followed by sterile saline alters interpretation of fluoroscopic images during fluoro-urodynamics.

MATERIALS AND METHODS

Subjects were randomized to receive 250 mL of intravesical contrast followed by sterile saline until maximal cystometric capacity vs non-dilute intravesical contrast alone during fluoro-urodynamics. Interpreters, blinded to study group, graded images on an ordinal rank scale rating confidence in image interpretation. Primary endpoint was differences in image interpretation between the two groups using visual grading characteristics curves and contrast-to-noise ratios (CNR). Secondary endpoints were obtaining anthropometric data such as body mass index and waist circumference to determine predictors of CNR in a multivariate multiple regression analysis.

RESULTS

26 subjects were randomized to receive dilute intravesical contrast and 22 non-dilute contrast; two subjects were unable to complete the study. There was no difference in baseline characteristics between the two groups. Visual grading characteristics demonstrated no difference in readability of the fluoroscopic images between groups and CNR was not statistically different between the two groups. No correlation was identified between CNR and waist circumference or body mass index.

CONCLUSION

Interpretation of fluoro-urodynamic images and image quality was not altered with using of 250 mL of contrast followed by saline. Expert reviewers did not perceive a difference in their confidence to distinguish between the two groups. Fluoro-urodynamics can be reliably performed using only 250 mL of contrast without compromising the ability to read the fluoroscopic images.

Radiation Exposure During Videourodynamics: Establishing Risk Factors

OBJECTIVES

The use of fluoroscopy during urodynamics can be helpful in the evaluation of patients with lower urinary tract dysfunction. However, fluoroscopy introduces the potential hazards of ionizing radiation, including malignancy. In this study we analyzed the data for radiation exposure during videourodynamic study (VUDS) at our center; we have also tried to establish the factors associated with increased exposure to radiation during VUDS.

METHODS

We reviewed all VUDS from August 2010 to May 2011. Patients were included if they were ≥18 years old and had data recorded on total radiation exposure (radcm² ). Age, sex, body mass index, fluoroscopy time, diagnosis, and urodynamic findings were recorded. Multivariate linear regression analysis was used to identify independent risk factors that influenced increased radiation exposure.

RESULTS

A total of 203 videourodynamic studies were assessed in 106 female and 97 male patients with a mean age of 64.3 and body mass index of 26.8. The average fluoroscopy time was 100.2 sec and exposure was 560.9 radcm² . The most common indication for videourodynamics was incontinence, 40.9%. On multivariate linear regression analysis body mass index, vesico-ureteral reflux, sex, number of fill cycles, and larger capacity were independent predictors of increased radiation exposure.

CONCLUSIONS

We have shown that increased radiation exposure as measure with Dose Area Product during VUDS was significantly associated with larger BMI, female gender, larger bladder capacity, presence of VUR, junior operator, and higher number of fill cycles. Further studies are now underway to attempt to reduce exposure based on these findings.

When should video be added to conventional urodynamics in adults and is it justified by the evidence? ICI-RS 2014

AIMS

To debate and evaluate the evidence base regarding the added value of video to urodynamics in adults and to define research questions.

METHODS

In the ICI-RS Meeting 2014 a Think Tank analyzed the current guidelines recommending video urodynamics (VUD) and performed a literature search to determine the level of evidence for the additional value of the imaging with urodynamic assessment of both neurogenic and non-neurogenic lower urinary tract dysfunction.

RESULTS

Current guidelines do not specify the added value of imaging to urodynamics. Recommendations are based on single center series and expert opinion. Standard imaging protocols are not available and evidence regarding the balance between number and timing of pictures, patient positioning, and exposure time on the one hand and diagnosis on the other hand is lacking. On the basis of expert consensus VUD is relevant in the follow-up of patients with spinal dysraphism. Evidence for the value of VUD in non-neurogenic lower urinary tract dysfunction is sparse. There is some evidence that VUD is not necessary in uncomplicated female SUI, but expert opinion suggests it might improve the evaluation of patients with recurrent SUI.

CONCLUSIONS

There is only low level evidence for the addition of video to urodynamics. The ICI-RS Think Tank encourages better reporting of results of imaging and systematic reporting of X-ray doses. Specific research hypotheses regarding the added value of imaging are recommended. The panel suggests the development of standards for technically optimal VUD that is practically achievable with machines that are on the market.

Is there a link between preoperative fluoroscopic cough stress testing and synthetic midurethral tape outcome?

OBJECTIVES

The primary aim of our study was to assess the utility of fluoroscopic cough stress testing as a predictor of synthetic midurethral tape (MUT) outcome. The secondary aim was to examine whether baseline demographics, clinical symptoms and urodynamic variables could predict MUT success.

STUDY DESIGN

We carried out a retrospective study including women with stress urinary incontinence (SUI) who underwent retropubic MUT in a tertiary referral urogynaecology unit. We excluded cases where concurrent pelvic organ prolapse surgery was performed. Patients were subdivided into groups based on the pre-operative fluoroscopic cough stress testing, using Blaivas and Versi classifications. Subjective outcome was evaluated at 6 weeks based on self-reported SUI in the symptom domain of the King's Health Questionnaire. Logistic regression models were used to identify predictors of treatment success.

RESULTS

143 patients were included in the study. Blaivas and Versi classifications were not useful in predicting subjective success (p=0.44 and p=0.40, respectively). Baseline demographics, clinical and other urodynamic variables failed to predict subjective outcome.

CONCLUSIONS

Fluoroscopic cough stress testing is not a useful predictor of MUT outcome. No preoperative variables have been found to predict MUT success.