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The value of maximal urinary flow in diagnostics of bladder outlet obstruction in males
Article published in Urologia Polska 2005/58/1.


Maciej Kisiel, Henryk Konon
Oddział Urologii Wojewódzkiego Szpitala Specjalistycznego w Białej Podlaskiej
Ordynator oddziału: dr n. med. Henryk Konon


urinary tract, bladder outlet obstruction, uroflowmetry, maximal urinary flow


Assessment of bladder outlet obstruction (BOO) allows to qualify the patient for surgical treatment. The problem of non-invasive diagnosis of BOO remains unsolved.
the aim of the study
Assessment of maximal urinary flow (Qmax) as useful in predicting bladder outlet obstruction in men.
material and methods
Between 18.11.2002 and 21.01.2004, 100 men aged 43-79 years underwent urodynamic examinations at the Urology Department of the Regional Specialist Hospital in Biała Podlaska. Uroflowmetry was performed first, followed by miction cystometry, in search for correlation between Qmax values and the presence of bladder outlet obstruction (BOO). The patients were divided into three groups: group I - patients with Qmax below 10 ml/s (n=31), group II - patients with Qmax from 11 ml/s to 15 ml/s (n=30) and group III - patients with Qmax exceeding 15 ml /s (n=39).
Results. In the first group (Qmax below 10 ml/s), bladder outlet obstruction was found in 21 patients (58.33 %), BOO present in the intermediate zone in 8 (27.59%) and no BOO in 2 (5.71%). In the second group (Qmax 10-15 ml/s), BOO was found in 9 patients (25%), in 10, BOO was present in the intermediate zone (34,48%), and 11 (31.43%) had no BOO.
In the third group (Qmax >15 ml/s), BOO was present in 6 patients (16,67%), in 11 (37.93%) it was in the intermediate zone, and 22 (62.86%) had no BOO. There was a statistically significant correlation (c2=26.24; p=0.00003) between Qmax and the presence of BOO in the pressure-flow test.
The value of maximal urinary flow for predicting BOO in men is low. Urodynamic examination should be considered before the patient is qualified for surgery.


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Maciej Kisiel
Oddział Urologii WSS w Białej Podlaskiej
ul. Terebelska 57-65
Biała Podlaska 21-500
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