Influence of catheterisation on the results of sonographic urethrocystography in patients with genuine stress incontinence.

Using introital sonography as an alternative to lateral chain urethrocystography during urodynamic studies, a prospective investigation was carried out in 47 patients with lower urinary tract complaints, to determine the correlation of sonographic assessment with and without bladder catheterisation. The apparent location of the bladder neck in relation to the pubic symphysis and measurements of the posterior urethrovesical angle at rest and during straining during cystometry with and without intravesical urodynamic pressure transducers were determined. In 22 (46.8%) patients the bladder neck at rest was below the lower edge of the symphysis. This finding was not influenced by the presence of a catheter. Correlation coefficients (r) for posterior urethrovesical angles at rest and during straining measured with and without catheters were 0.95 (95% confidence limits 0.92-0.98; P < 0.01) and 0.98 (95% confidence limits 0.96-0.99; P < 0.01), respectively. The coefficients of determination (r2) at rest and during straining were 0.92 and 0.95, respectively. Sonography with and without cystometry equipment in place gave similar results.