Unstable bladder: urodynamic diagnosis and observations in evaluating urinary incontinence in the female.

Unstable bladder in the female has been the subject of controversy with regard to its etiology, identification, and treatment. One hundred thirty consecutive female patients referred with incontinence were evaluated as to their symptoms and urodynamic findings. A stress cystometrogram, systematically done, was introduced and observations were made regarding certain findings on the urodynamic examination. These criteria were used subsequently for making a diagnosis of unstable bladder. Forty per cent of these patients were found to have an unstable bladder. History of frequency and urgency correlated best with a diagnosis in 70 to 80 per cent of our cases, and the new stress cystometrogram proved to be the most sensitive urodynamic test (78%) for detecting this condition. A systematic approach such as we describe is advocated as a first step toward gaining a better understanding of this puzzling entity.