Neurogenic bladder

Abstract

The prevalence of children with a neurogenic bladder dysfunction secondary to spina bifi da has been decreased in the last decades after the wide prenatal ultrasono-graphic screening and the prophylactic use of folic acid during pregnancy. Nevertheless, there are still many children presenting with signs of neurogenic bladder for other causes than spina bifi da. In this chapter we will deal only with neurogenic bladder secondary to neurological lesions, we have not considered the important variant of non neurogenic bladder dysfunction. Although the management of these children has been signifi cantly modifi ed during the last decades, the main goals of the treatment did not change: preventing urinary tract deterioration and obtaining continence at the expected social age to improve the social insertion of these children. The first step in investigating a child with a suspected bladder dysfunction is a thorough clinical examination (Table 89.1). This routine examination is very important, especially in occult spinal lesions, not to miss any underlying neurological pathology in children with voiding dysfunction. Once the clinical examination is done, and the voiding diary is established, we usually start with non invasive investigations: renal and bladder ultrasound, urine fl owmetry associated with EMG and post void residual estimation. More invasive investigations are done according to these results and on the underlying neurological pathology. There are many classifi cations describing neurogenic bladder dysfunction. Most of these classifications are depending on the site of the neurological lesions, well adapted to adult pathology but not to congenital spinal lesions. In fact, in children there is poor correlation between the spinal level of the lesion and the clinical impact. For this reason, classifi cation based on clinical disorders and urodynamic findings are more practical to be used in children. Main dysfunction is due to either detrusor or urethral sphincter dysfunction. The four main anomalies are defined as: overactive detrusor, under active detrusor, overactive sphincter, or under active sphincter. Many patterns can be the results of combinations of these four anomalies. The most common is the DSD (Detrusor Sphincter Dyssynergia), which is usually secondary to overactive detrusor with overactive sphincter. Because urodynamic investigation has become such an integrated part of any discussion of the management of neurogenic bladder, it is mandatory to know the defi nition and specifi city correlated to children. The standardisation of the terminology to be used in childrens bladder dysfunction has been established by the International Childrens Continence Society. The first difficulty to perform urodynamic study in a child is to give the optimal conditions and to do it in a cooperating child. It is important to explain the full procedure to the child and his family assisted by a booklet with simplifi ed explanations. A detailed past and present history is taken. Voiding diary is fi lled out by the parents before coming to the urodynamic study. Any constipation should be treated effi ciently by a bowel program to empty the rectum on the day of the study. Premedication is sometime needed in sensitive children, in our current practice we use routinely the Meopa® to introduce the catheter, and then the child is under no medication during the study to be able to detect his first voiding desires and also to be able to void when needed during the study. There are many methods of urodynamic studies, but the common basic principles specifi c to children are the following: smaller catheter, rectal pressure measurement, urethral profi le is measured, the rate of bladder filling should be adapted to the expected bladder capacity (usually divided by 10 min), EMG of external sphincter measured either by needles under local anaesthesia or by surface patches. The study is usually completed by measuring the voiding pressures, if the child is able to void by himself. Video urodynamic has gained popularity in the last decades. Visualisation of the bladder and bladder neck during filling and the urethra during voiding has added more accuracy in the determination of voiding dysfunction, confirming the location of the external sphincter during measurement, or measuring the bladder pressure when refl ux is associated. The most common cause for neuropathic bladder dysfunction in children is the congenital spinal anomaly. The main lesions are summarised in Table 89.2. We are going to describe the expected fi ndings and the modalities of follow up of the most common of these pathologies. © 2009 Springer Berlin Heidelberg.