Carbon dioxide versus water for cystoscopy: a comparative study.

In a prospective study of 120 patients, the cystoscopic views provided by carbon dioxide (CO2) insufflation of the bladder were compared with the views obtained during standard water cystoscopy. The clarity of vision was uniformly good during CO2 cystoscopy and in 21 patients with haematuria the views were significantly better than those obtained by standard water cystoscopy. There was no evidence of any significant absorption of CO2. This safe and simple technique would seem to have considerable advantages in the investigation of patients with haematuria.