Biomedical subjects

Ildefonso Delgado Elipe

Publications and source records attributed to Ildefonso Delgado Elipe.

2 recordsLinked to original sources

PubMed2003

[Urodynamic fundamentals, flow curve and urethral echo-Doppler. (Calculation of the urination strength and spectral power].

OBJECTIVES: We present the calculation of two parameters of practical interest for the urologists, which help to understand bladder phenomena. They are the real (total) power developed during micturition, and the spectral power of the flow curve, considered this as a finite time discrete signal. METHODS: We use Doppler ultrasound to calculate the propelling power of the urine towards the exterior. The calculation of the spectral power is included among the auxiliary calculus methods employed for the calculation of the contractile power in those cases in which the flow curve has several humps; we could only calculate the real power in one of them because the Doppler only measured the speed in one curl. RESULTS: We report one case with several curls in the flow curve, in which we could only test speed in one of the curls. The calculation of the spectral power allows us to compare curls and to calculate the total power just by addition. CONCLUSIONS: These two power measures are the expression of the same phenomenon, but they are different, showing one the micturition process from the flow curve and the other one from bladder contraction. We believe it is interesting to know them as a useful work tool. In the same way, the usefulness of Doppler ultrasound to obtain the values of urine speed through the urethra is demonstrated, a necessary data for the calculation of the bladder contractile power.

Algorithms↗

PubMed2002

[Urodynamics foundations: contractile potency and urethral doppler].

OBJECTIVES: To calculate the bladder softening factor, elastic constant and contractile potency. METHODS: For the analysis we considered bladder behavior like that of a spring. See articles 1 and 2 published in this issue. Using flowmetry, Doppler ultrasound and abdominal pressure (Transrectal pressure register catheter) an analytical solution that permits calculation of factors defining bladder behavior was looked for. Doppler ultrasound allows us to know urine velocity through the prostatic urethra and, therefore, to calculate bladder contractile potency. RESULTS: Equations are solved reaching an analytical solution that allows calculating those factors that define bladder behavior: Bladder contractile potency, detrusor elastic constant, considering it behaves like a spring, and calculation of muscle resistance to movement. All thanks to Doppler ultrasound that allows to know urine speed. CONCLUSIONS: The bladder voiding phase is defined with the aforementioned factors; storage phase behavior can be indirectly inferred. Only uroflowmetry curves, Doppler ultrasound and abdominal pressure value are used. We comply with the so called non invasive urodynamics although for us it is just another phase in the biomechanical study of the detrusor muscle. Main conclusion is the addition of Doppler ultrasound to the urodynamist armamentarium as an essential instrument for the comprehension of bladder dynamics and calculation of bladder behavior defining factors. It is not a change in the focus but in the methods, gaining knowledge and diminishing invasion.

Mathematics↗