722 Fig. 1 Classification of the neu- rogenic bladder, with four sub- types (a–d) according to dysfunctional activities of sphincter and detrusor. For each subtype, clinical implications if untreated and principles of management are summarized Pediatr Nephrol (2008) 23:717–725 later age need surgical intervention on the sphincter (e.g. sling operation). An important caveat here is that detrusor instability may emerge only after surgical improvement of outlet resistance. If this detrusor instability would remain unrecognized and untreated (with oxybutynin), bladder- outlet surgery would have converted a “wet but safe” into a “dry but unsafe” bladder. In the last dysfunctional subtype (type D), the bladder leaks due to detrusor instability and gradually becomes unsafe due to secondary bladder-wall changes with detrusor hypertrophy and loss of bladder compliance. Therefore, treatment consists of CIC combined with oxybutynin and, at a later age, bladder-outlet surgery. Once appropriate therapy has been initiated, adequate follow-up is required, with adjustments if needed (CIC frequency, medication dosing and administration route). Treatment efficacy can be assessed using clinical parame- ters (including CIC frequency and volume charts), urinal- ysis, renal and bladder ultrasound, X-ray cystography, and video urodynamics. As long-term sequelae of insufficiently treated neuro- genic bladders (renal scarring, noncompliant fibrotic blad- der) already have their origin in the first years of life, the frequency of multidisciplinary follow-up visits must be age dependent (3× yearly up to age 3 years, 2× yearly in school-aged children, yearly in adults). Typically, urinalysis and ultrasound are performed at all visits, cystography to investigate unexpected upper urinary tract infections, and urodynamics periodically to verify that under treatment, the catheterized bladder volumes are age appropriate [54] and stored under safe pressure conditions (storage of expected bladder capacity at pressures below 30 cm H2O; see [55]). With early instituted and optimal treatment, the large majority of patients can be adequately controlled without antireflux surgery or surgical bladder augmentation (Fig. 2). Augmentation cystoplasty is limited to a small group of patients in whom medical treatment fails (persistence of high filling pressures). In patients with insufficient sphinc- ter activity, continence achievement will require bladder- outlet surgery in addition to medical treatment. In female wheelchair users, surgical intervention to provide a conti- nent stoma will facilitate self-catheterization. Long-term outcome evaluation and need for life-long follow-up Lifelong follow-up with further periodic investigations of upper urinary tract changes, renal function, and bladder status is extremely important. There are two reasons why long-term outcome evaluation in adulthood and life-long patient follow-up are indispensable. First, for the individual patient, therapy is a life-long requisite, and verifying preservation of the patient’s kidneys is only possible by repetitive assessment throughout adolescence and adult- hood. Second, in general, detailed long-term follow-up data will show whether a treatment policy driven by long-term goals is sufficiently effective or requires further adaptations. The effectiveness of efforts preserving upper urinary tract function can only be judged by assessing the ultimate outcome once these patients have reached adolescence or adulthood [29]. In populations with NBSD, no consensus exists as to how renal status is ideally evaluated [56]. In clinical practice, upper urinary tract deterioration or protection is often monitored by radiographic images of hydronephrosis and vesicoureteral reflux. Modalities used to look at renal functions include nuclear imaging [dimer- captosuccinate acid (DMSA) renal scan], urinary concen- trating ability, and glomerular filtration rate assessment. For the latter, creatinine (Cr) clearance can be used for patients who are socially continent; for others, inulin or Cr ethylenediaminetetraacetate (EDTA) clearance can be used. Which (combination) of these tests is best to evaluate renal function requires further investigation [56].