Urodynamic examinations

Uroflowmetry (UFM)

Uroflowmetry - normal find

• Non-invasive measurement flow rate urine ( amount urine for time − Q = ml/s);
• if pathological results we indicate a PQ study ;
• for execution this examination is needed sufficient micturition volume (at least 150 ml);
• depends on quality detrusor, fill bladder, patency throats and urethras;
• patient urinate into specially adjusted toilets , urine turns out on constantly a rotating disk that is a stream urine braked − quantity energy needed to maintain constant the rotation is direct proportionately weight falling urine;
• on curves we evaluate:
  • whether the flow is continuous or dashed;
  • maximum flow (maximum flow rate, Q_max) − men above 15 ml/s, women above 20 ml/s;
  • average flow;
  • further timewise delay between the beginning efforts to micturition and the beginning micturition (up to 5 s), shape ascending parts, time achievement maximal micturition (steep), volume micturition, total time, average flow rate, total face curves;
  • Q_max < 12ml/s means obstruction whose hypoactivity urinary bladder .

The investigation is being evaluated according to worked out of nomograms because maximum and average flow urine changes depending on micturition volume.

Filling cystometry

• We determine value detrusor pressure during fulfillment urinary bladder by catheter (P_detrusor = P _ves − P _abd );
• during examination an intravesical and rectal catheter is inserted;
  • intravesical catheter measures intravesical pressure;
  • rectal catheter measures abdominal pressure.
• At examination we evaluate:
  • sensitivity of the detrusor − patient indicates feeling the first, normal and strong compulsion on urine These information they are considered with maximum capacity urinary bladder;
  • activity of the detrusor − for physiological conditions does not occur during fulfillment of the so-called uninhibited contractions of the detrusor, which manifest themselves sudden and wavy rise pressure;
  • capacity of the detrusor − in an adult human is normal capacity bladder between 350–500 ml;
  • compliance of the detrusor − describes compliance walls urinary bladder. This is a share volume and change pressure (ml/cm H₂O). Physiological value is approximately 20 ml/cm H₂O.

Miction cystometry

• Otherwise also manometric-flow study, pressure-flow study, PQ study, simultaneous urodynamic entry ;
• we determine detrusor pressure during micturition;
• this is dynamic examination with record current urine, intravesical pressure during micturition and intra-abdominal pressure ;
• indicated from differentially diagnostic reasons for:
  • benign hyperplasia prostate and weak current on UFM to reduced contractility detrusor;
  • irritating micturition symptomatology and strong current on UFM to rule out obstruction lower ones honor urinary.

Determination of Leak point pressure

• Determination values intravesical pressure, at which occurs escape urine from the bladder .

It has two forms.

Abdominal

• the so- called valsalva (LPP–VLPP);
• we measure help rectal catheter;
• for diagnostics stressful incontinence (used therefore especially in women);
• Mon application rectal catheter we invite the patient to cough (Valsava's maneuver), and we observe whether and at what kind pressure runoff occurs urine;
  • if value abdominal pressure is at incontinence higher than 90 cm H₂O, this is probably hypermobile urethras;
  • if value abdominal pressure is at incontinence less than 60 cm H₂O, this is most likely an insufficiency urethral sphincter;
  • values between 90 and 60 cm H₂O are in a “gray zone”.

Detrusor

• The so- called BLPP (bladder leak point pressure);
• the catheter is in the urinary tract bladders;
• examination is indicated at risk vesicoureteral reflux, e.g. in children with congenital developmental defects;
• values above 40 cm H₂O (in children above 40 cm H₂O) are unfavorable from the point of view emergence megaureters.

Profilometry

• At sliding out measuring catheter constant at blistering speed we record pressure in the urethra;
• or urethral pressure profile;
• not performed routinely ;
• at use stressful of maneuvers (cough) is stress profilometry.

Videourodynamics

• Combination filling cystometry and PQ study with rtg cystography, or ultrasonography;
• most complex, however laborious, that's why it's not done often

Links

Source

• SOBOTKA, R. Urodynamic examinations [lecture for subject Urology, specialization General medicine, 1.LF UK]. praha. 12/12/2013. 

• BENEŠ, Jiří. Study materials [online]. ©2007. [cit. 2009]. <http://www.jirben.wz.cz/>.