The successful research of modern cystometry and urethrometry, the improvement of manometric methods and the rational application of electronic computer technology have made the urodynamic examination technique more complete, and simultaneous examination of multiple items can be performed. The function of the vesicourethra not only depends on the anatomical characteristics of its own tissue structure, but is also regulated by the central nervous system and influenced by the function of other tissues and organs of the body. Many drugs can directly or indirectly affect the function of urination.
In the pathogenesis and clinical diagnosis and treatment of voiding dysfunctional diseases, urodynamic examination, as an accurate and reliable tool and method, can provide an objective criterion and thus improve the targeting of treatment. The following is a summary of the performance of some common functional diseases of the vesicourethra in urodynamic examination.
I. Diagnosis and differential diagnosis of unstable bladder
There are many reasons for the formation of an unstable bladder, the main ones being.
①Bladder outlet obstruction ;
②Post-operative peribladder neck;
(iii) idiopathic unstable bladder.
Many diagnostic information can be obtained from history and signs, but a more accurate diagnosis depends on urodynamic examination.The diagnostic criteria of ICS are: if there is involuntary contraction of the detrusor muscle when the cystoplasty (CMG) is higher than 15 cmH2O, it is an unstable bladder; in addition, there is an unsuppressed detrusor contraction when the detrusor pressure is lower than 15 cmH2O. The diagnostic conditions of unstable bladder are clear, but it is easy to confuse with many diseases in clinical work, resulting in poor outcome.
Common differential diagnoses are.
(1) unstable bladder combined with bladder outlet obstruction due to benign prostatic hyperplasia (BPH). About 60% of patients with BPH often have urinary frequency (mainly nocturia) and urge incontinence in addition to dyspareunia. 70% of them have a positive ice water test which may be related to physiological changes in the urinary reflex. These patients may present with an unstable bladder on urodynamic examination, and the isovolumetric contraction test of the detrusor muscle is of great clinical value in distinguishing the presence of an unstable bladder and may provide a reference for surgical prognosis.
The lack of improvement in postoperative urinary frequency and urge incontinence may be related to altered spontaneous contraction rhythms and irreversible neurological changes in the forced urinary muscle.
(2) Female stress urinary incontinence combined with urge incontinence, also known as mixed incontinence. Sand found that 55% of patients with an unstable bladder had improvement in symptoms after surgery.
(3) Children with unstable bladder combined with enuresis. Most nocturnal enuresis is not associated with abnormal bladder function, but in some children enuresis is accompanied by daytime frequency and urge incontinence symptoms, which require detailed urodynamic examination for diagnosis.
(4) Unstable bladder combined with vesicoureteral reflux in children. In children, the forceful contraction of the urethral sphincter to prevent incontinence raises the intravesical pressure causing vesicoureteral reflux. Up to 40% of children with vesicoureteral reflux have been reported in the literature to have an unstable bladder.
(5) Urge incontinence due to chronic urinary tract infection. In this case, the urinary routine is basically normal, and the urodynamic examination shows an early onset of dysuria, along with. It is accompanied by involuntary contraction of the detrusor muscle. The urodynamic examination results are normal in the asymptomatic period.
Second, the diagnosis and classification of urinary incontinence
The etiology of incontinence can be divided into three categories: high bladder pressure, low urethral pressure or high bladder pressure combined with low urethral pressure. In addition to the diagnosis and classification of urinary incontinence combined with medical history and physical signs, urodynamic examination can provide a reliable basis to help understand the mechanism of urinary incontinence. Urge incontinence can be divided into motor and sensory. Motor incontinence is manifested by.
(1) decreased urethral resistance, and incontinence develops when the intravesical pressure generated by uninhibited contraction of the detrusor muscle is greater than the urethral closing pressure.
② Urethral resistance is normal, the bladder neck opens in a funnel shape from the image, a small amount of urine enters the posterior urethra, and urinary incontinence occurs when the bladder neck closes after the contraction of the detrusor muscle is completed and the urethral dilator muscle is relaxed. Sensory urge incontinence is caused by various inflammatory stimuli. The bladder exhibits low compliance and the intra-vesical pressure rises when bladder perfusion is small, while easily causing incontinence due to uninhibited contraction of the detrusor muscle.
For true stress incontinence, urodynamic testing is indispensable. Cystometry can reveal whether the incontinence is simple stress incontinence or symptomatic stress incontinence due to abnormal bladder function. In simple stress incontinence, the bladder void pressure is less than 10 cmH2O, the filling pressure of the detrusor muscle is less than 25 cmH2O, there is no uninhibited contraction of the detrusor muscle and compliance is normal. However, symptomatic stress incontinence due to motor urge incontinence, low compliance bladder, and filling incontinence can have a filling pressure of up to 52.0 ± 29.54 cmH2O in the forced urinary muscle and a large amount of residual urine.
Functional urethral length can be measured by static urethrogram, and Min Ye et al. found that functional urethral length was significantly shortened in stress incontinence (5). Determination of maximum urethral pressure is the main indicator for diagnosis, and Hilton reported maximum urethral pressure of 60.9 ± 11.2 cmH2O in mild stress incontinence and 41.1 ± 14.5 cmH2O in severe cases, with a normal value of 80.8 ± 26.4 cmH2O.