Usefulness of a newly developed tele-operating system for non-invasive ultrasound urodynamics

We previously reported a non-invasive, transperineal, urodynamic technique using Doppler ultrasonography. Recently, we developed a new tele-operating system to control the robotic arm of the ultrasound probe that has a pressure-regulating function and a touch-panel that allows the operator to monitor the exact position of the probe. From January 2008 to April 2010, 61 cases were examined using this system. Among them, 41 cases were examined by 2 experienced doctors and 20 cases were examined by 5 inexperienced nurses. We then compared the success rate of taking images sufficient for analyzing the velocity parameters and preparation time for setup between these two groups. In 45 out of 61 cases, whose examinations were successfully carried out, the velocity-flow parameters were compared between 19 cases with bladder outlet obstruction (BOO) and 26 without BOO. Satisfactory images were obtained in 32 cases (78%) by doctors and in 13 cases (65%) by nurses. The preparation time was 9.8 seconds for doctors and 13.2 seconds for nurses, with no statistical difference. The functional cross-sectional area in the prostatic urethra (A1) was significantly smaller in the BOO(+) group (0.056?) compared to the BOO(-) group (0.360?). The velocity ratio (VR) was significantly higher in the BOO(+) group (1.89) than in the BOO(-) group (0.41). In conclusion, the newly developed tele-operating system has made it easier for an inexperienced examiner to obtain velocity parameters using Doppler ultrasound urodynamic measurement

Retroperitoneoscopic pyelolithotomy as initial treatment for upper urinary tract large stone.

We report a case in which retroperitoneoscopic pyelolithotomy was the procedure selected to treat a large stone in the upper urinary tract. A 71-year-old woman who had multiple cerebral infarction and dementia was admitted with a persistent high fever unresponsive to antibiotics. The diagnosis was pyelonephritis and urosepsis associated with ureteral calculus. A large calculus(3.0 x 2.0 cm)was found in the left ureter at the L3 level. She underwent nephrostomy of the left side. After the patient's general condition had improved, surgery was performed successfully with an uneventful recovery. The findings in this case confirm that retroperitoneoscopic surgery allows removal of a large stone in a single, minimally invasive procedures.</p

Use of Doppler ultrasound for non-invasive urodynamic diagnosis

Objectives: A totally non-invasive transperineal urodynamic technique using Doppler ultrasonography has been developed. Methods: Since normal urine does not have blood cells, urine was thought not to produce the Doppler effects. However, basic studies confirmed that the decrease of pressure at high velocity (Bernouilli effect) caused dissolved gas to form microbubbles, which are detected by Doppler ultrasonography. Subjects sat and the probe was advanced via remote control to achieve gentle contact with the perineal skin. The digital uroflow data signals and the color Doppler ultrasound video images were processed on a personal computer. The flow-velocity curves from two sites; the distal prostatic urethra just above the external sphincter (V1) and the sphincteric urethra (V2) were plotted against time. The parameters of both the pressure-flow studies and the Doppler ultrasound urodynamic studies were compared in men who had various degrees of obstruction. Results: Functional cross-sectional area at prostatic urethra (A1), calculated by Q max /V1, was lower in the group of bladder outlet obstruction (BOO) vs. control group. Velocity ratio (VR), which was calculated by V1/V2, was the parameter having the best correlation with BOO index, though A1 had a similar correlation. This method is viable to diagnose the degree of BOO. Conclusions: The development of non-invasive Doppler ultrasound videourodynamics (Doppler UDS) will dramatically expand the information on voiding function