Cryoprostatectomy, the use of subzero temperatures to ablate prostate
tissue gained favour in the 1960s because of its speed and lack of hae
modynamic effects. It fell from use because the freezing process could
not be monitored and this led to a high incidence of local complicati
ons. We have performed transrectal real time ultrasound in 12 patients
undergoing cryoprostatectomy. In all the freezing process was easily
visualized as an advancing hyperechoic 'iceball' with distal acoustic
shadowing. Monitoring allowed maximum prostate ablation without breach
ing the prostatic capsule. There were no significant complications and
all but one patient gained symptomatic relief. Ultrasound at 1 month
showed a heterogeneous echo pattern with very little cavity formation
but by 3 months a significant cavity was seen. This study demonstrates
that it is possible to monitor the freezing process during transureth
ral cryoprostatectomy. This, theoretically, should significantly reduc
e the local complications encountered in previous studies.