Trans-rectal Ultrasound-Guided Autologous Blood Injection in the Interprostatorectal Space Prior to Percutaneous MRI-Guided Cryoablation of the Prostate.

OBJECTIVE: To report a novel technique of ultrasound-guided injection of autologous blood in the interprostatorectal space, in an attempt to facilitate ablative prostatic procedures by widening durably the space between the rectum and the prostate.

MATERIALS AND METHODS: Between April and November 2016, four consecutive patients underwent the haemoprotection injection technique. For each patient, we recorded the time to perform the technique, the amount of injected blood, the achieved distances between the rectum and the prostate post-injection at fixed defined points (apex, middle, and base of prostate at the midline, left, and right sides of the gland), the extension of the ice ball outside the prostate capsule at those fixed points, and whether any residual blood was present on 1-month follow-up MRI.

RESULTS: Mean time to perform haemoprotection injection was 54 min, with an average blood volume of 103 cc. Mean distance achieved at the apex, middle, and base of the prostate, respectively, was 12, 13, and 16 mm in the midline; 8, 10, and 13 mm on the left side; and 9, 10, and 13 mm on the right side. The mean extension distance of the ice ball beyond the capsule was 4, 6, and 6 mm in the midline; 4, 5, and 6 mm on the left side; and 1, 3, and 3 mm on the right side. No residual blood was present on 1-month follow-up MRI in all patients. No rectal fistula occurred.

CONCLUSION: Haemoprotection may create a safe and effective virtual space between the prostate and rectum.