Neurogenic Bladder in Infants and Children
The bladder can be divided into three parts: apex, body, and fundus. The detrusor muscle corresponds to the smooth muscle component of the bladder and forms a complex mesh of muscle bundles extending into the bladder neck as well as surrounding of the proximal urethra – thus forming the internal urethral sphincter. The striated external sphincter covers only the distal part of the internal urethral sphincter and extends than downwards to the level of the urogenital diaphragm. In the normal case, a single ureter, on each body side, enters the bladder on the lateral circumference at an angle of less than 45°. The trigone represents the area between the two ureteric orifices and the internal urethral meatus.