at first we must rule out organic cause of iritative symptoms such as UTI or diabetes melitus and insipidus .also we need to perform a through nerologic examination .if we rule out organic causes this urodynamic report Can be considered as evidence for overactive bladder .

What is the frequency? 8-10/day is normal. Check intake. 5ls/day will drive everyone to micturate frequently. Urge symptoms are a normal signal for micturition. It is only when the urge cannot be controlled that it is labelled as "OAB".

Flow chart indicates a normal stream. As for treatment, I would initially get them to do PFR using a squatting routine and to sit on a rubber fitball instead of a chair if they are an office worker. This is a very time-efficient PFR method and is very effective for pain, emptying,urge & nocturia. In the papers below we used a stimulator but havesince found that a rubber fitball is the most time efficient and effective method.

Petros PE and Skilling PM Pelvic floor rehabilitation according to the Integral Theory of Female Urinary Incontinence. First report, European Journal of Obstetrics & Gynecology and Reproductive Biology (2001) 94: 2, 264-269

Skilling PM,·Petros PE Synergistic non-surgical management of pelvic floor dysfunction: second report. Int J Urogyne (2004)15: 106-110

Is this confirmed with urodynamics or a simple uroflow? Urodynamics diagnosis would be best diagnostic tool for this to observe detrusor overactivity.

Prevalence of Over Active Bladder in the population is high. Urodynamics may not be possible in many situations.

AUA guidelines do not advise Urodynamics.

My specific question is; if very high peak flow rate and very short voiding time can be considered diagnostic of OAB

No the findings described should not be considered as OAB. The OAB is a clinical diagnostic associated with urgency. If patient has only frequency with a 300 ml in the bladder it is quite normal.

I think this might possibly be a form of mixed incontinence, because the patient 's flow rate seems moderately high. The only way to determine this is through a urodynamics study.

A bladder diary documenting fluid intake, true drequency during the day and overnight, voided volume and with an added note for urgency or incontinence would go a long way in establishing the diagnosis.

Is there any upper limit for 'Peak flow rate'?

Flow rate doesn't measure quantitative parameters of micturition but only qualitatives one.He is a "supervoider" or "overflower" and this indicates an increased bladder pressure micturition.He needs a upper urinary tract control to rule out dilatation of the pelvis. Overvoiders usually are neurologic patients

The problem here is urgency not flow. The only time urgency could be caused by an emptying defect is with a cystocele. An isolated flow rate as reported has little significance per se. A 10sec emptying time is very fast for 300ml, so it is unlikely that the patient has a cystocele. She may have a UTI or urgency from another cause.

Significance of urine flow rate

Urine flow rate is determined by intraurethral resistance which varies inversely to the 5th power of the radius (1) which ultimately depends on the ability of an external striated muscle mechanism to open out the urethra (2). The wide variation in flow rates noted in (2) when the flow test was repeated was attributed to this non-linear control of resistance to flow by the external striated muscle mechanism (2).

(1). Bush MB, Petros PEP, Barrett- Lennard BR On the flow through the human urethra. (1997) Biomechanics 30:9,967-969.

(2) Petros PE and Bush MB, A mathematical model of micturition gives new insights into pressure measurement and function. Int J urogynecology (1998) 9: 103-107.

Dear Dr. it was not mentioned whether that patient is male or female, and I saw most of replies considered that patient is male(he), of course it will be different in interpretation of the flow parameters between both sex. Flowmetry is the end result image between two factors detrusor contractility and urethral resistance, super voiders are mostly females with low urethral resistance and normal or high contractility. According to ICS definition of terms OAB is a clinical diagnosis whereas bladder over-activity is a urodynamic diagnosis with evident abnormal bladder contractions....on cystometry. which usually starts with low bladder volumes, where as in that case patient passed 300 ml and succeeded to evacuate without PVR, this will be increased contractility , not over activity. so such patient with such symptoms deserve to have full urodynamic study and flowmetry alone is not enough to conclude his or her symptoms.

Dear Ahmed

Your point about male and female is critically important as the dynamics are very different.

In the male it is narrowing of the urethral tube which causes the obstructive flow and often the accompanying urgency.

In the female it is failure to activate the external opening mechanism described in ref 2.

The ICS definitions do not apply to flow mechanics, which is a science in itself.

We have all seen patients leaking during urodynamic testing with no or even negative detrusor pressure on the graph.

Explanation

The micturition reflex is activated by the filling. If the external opening mechanism (described in reference 2.) opens the urethra sufficiently, the frictional resistance to flow may fall to a very low point where all the detrusor contractile force is converted to flow and no detrusor contraction is recorded with the pressure transducers. See graphs in refs 1&2 .

1). Bush MB, Petros PEP, Barrett- Lennard BR On the flow through the human urethra. (1997) Biomechanics 30:9,967-969.

(2) Petros PE and Bush MB, A mathematical model of micturition gives new insights into pressure measurement and function. Int J urogynecology (1998) 9: 103-107.

I agree with you Peter, that flow mechanics is a science in itself, but if you notice that super-voiding is not synonymous to over -activity, is the main message, in other words contractility of the bladder is different from activity......

Yes.

I am not certain what "supervoiding" means.

Yes, contractility of the bladder is different from "activity" as recorded by pressure transducers.

From our numerous studies of micturition over the years, it is possible to relate the following:

the bladder always contracts to empty and in doing so, creates a force which creates a head of pressure to drive the urine out of the bladder into the urethra and out. Where the confusion comes is that contractility is equated with rise in detrusor pressure. The detrusor contractility is constant. Observation by video xray during micturition shows that the bladder seems to spasm during emptying. This is consistent with the mode of electrical transmission for smooth muscle, muscle to muscle, not discrete innervation by a nerve for every fibre as in striated muscle. As a spasm would create a constant force, and as Pressure =Force/Area, if the area is sufficently large, then pressure recorded at micturition will fall, even to zero. In this context, pressure is an illusion. It is the frictional resistance of the urethral tube which determines the rate of urine expulsion. In turn this is dependent on the radius inversely to the 5th power.

super voiding is a description of those voiding with maximum flow rate(Qmax), higher than the mean (Qmax) adjusted for sex and age....

Thanks Ahmed

I had not heard that term before

Best

PP

These a case of high pressure high follow system..needs to evaluate with urodynamics.