title: Structural basis of neurogenic bladder dysfunction. II. Myogenic basis of detrusor hyperreflexia.
abstract: OBJECTIVE
  We describe the ultrastructure of detrusor smooth muscle in long-standing neurogenic bladder dysfunction in the human.
  
  
  METHODS
  Detrusor biopsies were obtained from (15 female and 31 male) patients 7 to 96 years old with neurogenic bladder dysfunction for less than 1 to 43 years. Of the patients 9 had meningomyelocele, 25 spinal cord injury and 12 brain disorder. Urodynamically, all patients had detrusor hyperreflexia (neurogenic detrusor overactivity) in addition to bladder outlet obstruction in 4, impaired detrusor contractility in 19, decreased bladder compliance in 4, and detrusor-sphincter dyssynergia in 24. Ultrastructural changes in detrusor, including those associated with detrusor overactivity, impaired detrusor contractility and bladder outlet obstruction, were evaluated qualitatively and quantitatively.
  
  
  RESULTS
  Intermediate junctions of muscle cells were absent or reduced in 45 biopsies, which instead had dominant intimate cell appositions with much narrower junctional gaps. A greater than 2 intimate cell apposition-to-intermediate junction ratio was present in 45 biopsies (98%), and intimate cell apposition linked chains of 5 muscle cells or greater in all biopsies (100%). Muscle cell degeneration was observed in 34 biopsies from 20 of 27 patients (74%) with normal contractility and 14 of 19 (74%) with impaired detrusor contractility. No particular changes were associated with functional bladder outlet obstruction due to detrusor-sphincter dyssynergia.
  
  
  CONCLUSIONS
  The ultrastructural complete dysjunction pattern is a feature of hyperreflexia as well as nonneuropathic detrusor overactivity of various etiology. A greater than 2 intimate cell apposition-to-intermediate junction ratio had 98% sensitivity but its specificity remains to be determined. The lack of relationship between muscle cell degeneration and detrusor contractility probably reflects limitations of urodynamic measurement of contractility in patients with spinal cord injury and meningomyelocele.
authors.affiliation: Department of Pathology, Upstate Medical University, State University of New York, Syracuse, New York, USA.
authors.forename: Axel
authors.initials: A
authors.lastname: Haferkamp
authors.forename: Joachim
authors.initials: J
authors.lastname: Dörsam
authors.forename: Neil M
authors.initials: NM
authors.lastname: Resnick
authors.forename: Subbarao V
authors.initials: SV
authors.lastname: Yalla
authors.forename: Ahmad
authors.initials: A
authors.lastname: Elbadawi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D009130:Muscle, Smooth / Q000503:physiopathology / Q000648:ultrastructure*; D009218:Myosins; D011446:Prospective Studies; D001750:Urinary Bladder, Neurogenic / Q000473:pathology* / Q000503:physiopathology
chemical_list: D009218:Myosins