Benign prostatic hyperplasia (BPH) is a common condition that affects older people with a prostate. Stromal and epithelial cells increase in number, causing the prostate to get bigger. It often happens in the periurethral region of the prostate, with large discrete nodules compressing the urethra. Symptoms include hesitancy during urination, interrupted or decreased urine stream (volume and flow rate), nocturia, incomplete voiding and urinary retention.
Mild symptoms are usually managed conservatively. Drugs may also be offered, such as alpha-adrenoceptor blockers and 5‑alpha-reductase inhibitors. If other treatments have not worked, surgical options include transurethral resection of the prostate (TURP), transurethral vaporisation, holmium laser enucleation, insertion of prostatic urethral lift implants, prostatic artery embolisation or prostatectomy (see NICE's guideline on lower urinary tract symptoms in men). Potential complications of some of these surgical procedures include bleeding, infection, urethral strictures, incontinence and sexual dysfunction.
Transurethral water-jet ablation for lower urinary tract symptoms caused by BPH uses a specialised system that combines image guidance and robotics for the targeted removal of prostate tissue.
The procedure is usually done under general or spinal anaesthesia. Transrectal ultrasound is used throughout the procedure. A handpiece with an integrated cystoscope and ablation probe is inserted through the urethra and into the bladder. When it is correctly positioned, planning software is used to create a personalised treatment plan. A high-speed jet of saline is then delivered to the prostate at various flow rates, to give targeted and controlled tissue removal, according to the treatment plan. The ablated tissue is aspirated through ports in the handpiece and can be used for histological analysis. Several methods are used to control bleeding, including cautery, a balloon catheter in the bladder (with or without bladder neck traction) and a balloon catheter in the prostatic fossa. After the procedure, a 3‑way Foley catheter is placed through the penis into the urethra and the bladder is continuously irrigated. The catheter is removed before discharge from hospital, usually on the day after the procedure.
A possible advantage of the procedure is the potential to preserve sexual function. The procedure does not use heat to ablate the prostate tissue, which removes the risk of complications from thermal injury.