544 [23, 24]. Because the subsequent risk of reflux is lower, the effect on renal function and the development of scarring is reduced when these prophylactically treated children are compared to those monitored with watchful observation [16, 25]. Credé voiding is not an efficacious form of bladder emptying in children with myelodysplasia, especially if the urethral sphincter is partially or fully innervated. Because most children have intact motor function above L1, any increase in abdominal pressure from a Credé maneuver can lead to a reflexive increase in urethral sphincter activity, thus producing an increase in bladder outlet resistance resulting in “high voiding pressure”. This can be particu- larly noxious in children with moderate or severe grades of reflux. In addition, as the child grows, the bladder resides more in the pelvis and not intra-abdominally, further reducing the effectiveness of the Credé maneuver. The key to a stable bladder and, consequently, renal function is the maintenance of a good capacity, highly compliant, detrusor muscle, combined with periodic and complete emptying of the bladder at low pressure. Anticholinergic medication (primarily oxybutynin, toltero- dine, glycopyrrolate, hyoscyamine or trospium) and CIC achieve that in a majority of children and provide an added benefit of continence if the child has reasonable bladder outlet resistance [9]. Several alpha sympathomimetic agents, such as phenylpropanolamine, ephedrine or pseu- doephedrine, are used to increase bladder outlet resistance when it is not sufficient to maintain continence between CICs. A variety of surgeries has been devised when these conditions cannot be met. A detailed description of the surgical treatment is beyond the scope of this discussion, but, suffice it to say, bowel augmentation onto the bladder has been a common practice to lower pressure and increase capacity in order to make the bladder a useful organ for storage. Disadvantages abound, including problematic mucus production, recurrent urinary infection, electrolyte imbalance, stone formation and the recently documented risk for the late occurrence of cancer in the augmented segment [26]. A plethora of surgical procedures has been designed to increase bladder outlet resistance in those children with a level that is insufficient to maintain continence between catheterizations, that include implantation of an artificial urinary sphincter, bladder neck tightening, using adjacent tissue, a fascial sling, and various bulking agents. All can provide more resistance, but no one procedure is ideally suited for every patient. Creating a catheterizable urinary stoma has become fashionable in those children with intractable urethral incontinence (with obliteration of the bladder neck) or inability to catheterize their urethra easily due to obesity, poor eye–hand coordination or caretaker issues surrounding Pediatr Nephrol (2008) 23:541–551 genital organ privacy. Long-term success has been achieved that provides the individual with a degree of independence, but problems with stomal stenosis can occur. Occult spinal dysraphism Occult spinal dysraphism has been diagnosed with increas- ing frequency since the advent of spinal ultrasound and MR imaging [27]. An intraspinal lipoma or lipomeningocele, a diastematomyelia, a fatty filum with tethering, or a dermal sinus tract make up the extent of these disorders. Most pediatricians now will image the back of any newborn with a cutaneous lower midline back lesion, which can be detected in 90% of affected individuals [28]. These lesions include a subcutaneous mass, dermal vascular malforma- tion, hypertrichosis, a midline dimple or sinus tract, a skin tag or an asymmetric gluteal cleft. These lesions often signify an underlying bony and/or spinal cord malforma- tion. Ultrasound within the first 3 months of the infant’s life can easily visualize the intraspinal space. After the infant has reached that age MR imaging is needed to diagnose and/or confirm the presence of a dysraphic state. Most infants have no other manifestation of this disease (other than the cutaneous lesion) because lower extremity neurologic function is normal. In the past, before intraspinal imaging was feasible, these lesions often went undetected until urinary and/or fecal incontinence became problematic or lower extremity difficulties became evident [28–31]. This frequently occurred around the time of a pubertal growth spurt, when increased traction on the spinal cord took place [32]. As the imaging techniques evolved and urodynamic studies in children were performed at an early age, it became clear that most babies had minimal neurologic impairment at first but that the neurologic lesion progressed with advancing age [33]. The pathophysiology involves apparent tension on the lower end of the spinal cord as the child grows. Normally, the conus medullaris ends at L1, L2 at birth but ‘rises’ cephalad to T12, L1 at puberty. The differential growth rate between the spinal cord and the vertebral bodies stretches the lower cord and cauda equina due to fixation of the filum terminale to the bottom of the vertebral canal, or the nerves roots emanating from the cord become compressed by an expanding intraspinal lipoma. With time, this stretching and/or compression affects the oxidative process of the neural tissue that then leads to impaired function of the lower extremities and/or lower urinary tract [34, 35]. Initial investigation of the affected child includes a urodynamics study and a renal and bladder ultrasound. The findings of urodynamics studies in children less than 1 year old are invariably normal, but when abnormal they are not coupled with abnormalities in the lower extremities [33,