To investigate the effect of earlier application of Clean intermittent Catheterization(CIC)in infants with neurogenic bladder(NB)．
Because during voiding, the bladder contracts, and internal and external sphincters and pelvic floor muscles relax to allow urine to pass through the urethra. Normally, after the bladder empties, a small amount of urine (less than75 ml), called the post-void residual (PVR), may remain in the bladder. If a person cannot urinate or empty the bladder completely, the PVR increases and can contribute to urinary tract infections (UTIs)and vesicoureteral reflux(VUR),and permanent damage to the bladder and kidneys. Incomplete bladder emptying or urinary retention may lead to the development of a neurogenic bladder, a general term referring to bladder or voiding dysfunction resulting from interrupted innervation from a lesion or disease in the central or peripheral nervous system. Neurogenic bladder can be caused by upper motor neuron disease,or spinal cord diseases such as spina bifida.By inserting the catheter several times during the day, episodes of bladder over distention are avoided.
It is well known that NB does not cause timely treatment of vesicoureteral reflux (VUR), hydronephrosis and urinary tract infections, and the quality of life is significantly reduced. After 1971, the widespread use of CIC effectively improved the symptoms of dysuria and urinary incontinence in children with detrusor-free reflexes. However, it is still controversial whether CIC will be started from the early diagnosis of infants and young children. This study compared the long-term efficacy of the CIC early treatment group (<1 year old) and the late treatment group (>3 years old), and provided a reference for the rational selection of CIC for NB.

Eighty-nine children with NB diagnosed in our urodynamic center were less than 1 year old when they first came to hospital from January 2009 to January 2012，and CIC was carried out at different ages．Sixty-four patients were followed up for a long time and were divided into early CIC group(children who begin CIC less than 1 year old )and late CIC group(children who begin CIC after 3 years old).
Meanwhile,29 patients were distributed in early CIC group including 19 boys and 10 girls with the mean age of(7.6±2.6)months．Among the ones, 4 cases were suffering from postoperative spina bifida manifesta；22 cases with spina bifida occulta；2 cases with sacral dysplasia；1 case with meningitis．
Late CIC group included 35 patients, including 20 boys and 15 girls with the mean age of(8.0 ±2.8)months)．Among which 2 cases were suffering from postoperative spina bifida manifesta；28 ones were with spina bifida occuha；4 cases were with sacral dysplasia；1 case with postoperative pelvic surgery．
Before the treatment,there were no significant differences of the bladder compliance(BC) between the groups.The safety bladder capacity(SBC) and the maximum cystometric capacity(MCC) between two groups also had no no statistical difference. Urodynamic parameters and complications of 64 patients who were successfully followed up for as long as 6 years were compared．

After 3 years following up，BC，SBC and MCC in early CIC group[(7.78±2.59)ml/cmH20，(134.74±19.42)ml，(140.26±13.13)ml were significantly higher than those of late CIC group[(6.63±2.62)ml/cmH20，(117.83±15.53)ml，(124.80±11.78)ml；all P<0.05]．
After 6 years following up，BC，SBC and MCC in early CIC group[(10.21±3.01)ml/cmH20，(213.32±24.48)ml,(220.53±15.59)ml]were significantly higher than those of late CIC group[(8.50±2.69)ml/cmH20，(194.28±29.71)mI，(206.63±17.90)ml；all P<0.05]，and the vesicoureteral reflux rate[24.1%(7/29)]in early treatment group was significantly less than that in late treatment group[54.3％(19/35)，P<0.05]．Increases in blood urea nitrogen(BUN )and serum creatinine were found in 6 eases(20.7%)in early CIC group and 17 cases(48.6%)in late CIC group，the difference was significant(P<0.05)．
Conclusion

For children with neurogenic bladder, especially in children with urinary dysfunction caused by congenital nervous system diseases, it is important to restore the function of storing urine and voiding of the bladder as possible as they can since birth.The ultimate goal is to protect the upper urinary tract function and kidney function, and to delay the rate of renal damage.There are many ways to protect kidney function. Whether it is medication, behavioral therapy or surgery, it will be individualized according to the patient's disease and severity.For bladders that have a certain function of storing urine, and also have a part of voiding function, it is also important to simulate the circulatory rhythm of periodic filling and emptying of the bladder. Therefore, regular CIC is also important.
This study focused on the initiation of CIC at different times in children with neurogenic bladder and the urodynamic assessment of children in the early CIC and late CIC groups. Regular follow-up was performed by urodynamics technology,the data of which were clear and conceivable, including BC, SBC, MCC, etc.,and if necessary, video urodynamics to determine the presence of vesicoureteral reflux and hydronephrosis is used.
From the data of the two treatment groups, it can be known that for children with NB, the bladder is evacuated by CIC within 1 year of age, and the physiological cycle of filling and emptying of the bladder can be simulated as early as possible. It not only protects the upper urinary tract, but also maintains sufficient capacity of the bladder, preserves compliance, and avoids early bladder atrophy and fibrosis and vesicoureteral reflux.At the same time, the standard CIC operation does not increase the chances of significant UTIs, but the timely emptying of the bladder and the reduction of residual urine can reduce the chance of UTIs.

For NB children,the effect of early CIC is better than that of late CIC. Treatment of CIC begining before 1 year old is recommended.

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