Postvesicular obstruction due to<unk><unk> s. Abdominal ultrasound is of some benefit, but not diagnostic. Features that suggest<unk> s are bilateral hydronephrosis, a thickened bladder wall with thickened smooth muscle trabeculations, and bladder diverticula. Voiding cystourethrogram (VCUG) is more specific for the diagnosis. Normal plicae circularis are variable in appearance and often not seen on normal VCUGs.<unk>  on voiding cystourethrogram is characterized by an abrupt tapering of<unk>  caliber near the verumontanum, with the specific level depending on the developmental variant. Vesicoureteral reflux is also seen in over 50% of cases. Very often the<unk> <unk> maybe dilated thus making the abrupt narrowing more obvious. the bladder wall may show trabeculations or sacculations or even diverticuli. Diagnosis can also be made by cystoscopy, where a small camera is inserted into the<unk> for direct visualization of the<unk> ly positioned<unk> . A limitation of this technique is that<unk><unk>  tissue is translucent and can be pushed against the wall of the<unk> by inflowing irrigation fluid, making it difficult to visualize. Cystoscopy may also demonstrate the bladder changes. Centers in Europe and Japan have also had excellent results with cystosonography, although it has not been approved for use in the United States yet. Classification The male<unk> laid open on its anterior (upper) surface.<unk><unk> s are usually fusion of the plicae colliculi between the entrance of the seminal vesicles at the veromontanum, and extend to the membranous<unk> <unk><unk>  obstruction was first classified by H. H. Young in 1919. The verumontanum, or mountain ridge, is a distinctive landmark in the prostatic<unk>  important in the systemic division of<unk><unk>  disorders: * Type I - Most common type; due to anterior fusing of the plicae colliculi, mucosal fins extending from the bottom of the verumontanum distally along the prostatic and membranous<unk> * Type II - Least common variant; vertical or longitudinal folds between the verumontanum and proximal prostatic<unk> and bladder neck * Type III - Less common variant; a disc of tissue distal to verumontanum, also theorized to be a developmental anomaly of congenital urogenital remnants in the bulbar<unk> Dewan has suggested that obstruction in the<unk> <unk> is more appropriately termed congenital obstructions of the<unk><unk>  membrane (COPUMs), a concept that has come from an in-depth analysis of the historical papers, and evaluation of patients with a prenatal diagnosis that has facilitated video recording of the uninstrumented obstructed<unk>  The congenital obstructive lesions in the bulbar<unk>  named Type III<unk> s by Young in 1919, have been eponymously referred to as Cobb's collar or Moorman's ring. For each of the COPUM<unk> <unk>  and Cobb's (Bulbar<unk>  lesions, the degree of obstruction can be variable, consistent with a variable expression of the embryopathy. The now nearly one hundred year old nomenclature of<unk> s was based on limited radiology and primitive endoscopy, thus a change COPUM or Cobb's has been appropriate.
Posterior urethral valve
Urethral caruncle
Hypospadias
Cloacal exstrophy
Epispadias
Mandibuloacral dysplasia
Bladder exstrophy
Urachal cyst