Laser prostate surgery is a minimally invasive surgery indicated for the treatment of bladder outlet obstruction due to enlargement of the prostate. It utilizes a powerful laser to either remove the complete gland or a portion of the prostate blocking the urethra, through cutting or vapourisation.
Laser prostate surgery is as effective as transurethral resection of the prostate (TURP), in terms of clinical outcome after the surgery. Apart from this it has additional benefits such as less bleeding; fewer complications, reduced catheter time and hospital stay with quicker resumption of normal activities.
Laser prostate surgery is performed under general or spinal anaesthesia and the laser is delivered through a flexible fibre passed through a cystoscope. A cystoscope is a tube like instrument with a light and a camera at one of its ends. The cystoscope along with the flexible fibre is inserted through the urethral opening of the penis. The real time images, from the cystoscope, are displayed on the monitor in the operation room. The surgeon controls the direction and delivery of the laser energy through the flexible fibre tube, under the guidance of real time imaging. Laser energy is delivered as small bursts, lasting for a few seconds, to either cut or vaporise the prostate tissue, depending on the type of laser prostate surgery performed. Continuous flow of irrigation fluid is maintained to remove the cut prostate tissue and also maintain a clear view of the operative area. The irrigation fluid also keeps the fibre tip cool. The cystoscope with the fibre is slowly manipulated through the urethra, removing the obstructing prostate tissue. This enlarges the space within the urethra and restores normal urine flow. At the end of the procedure a catheter may be placed in the bladder, which is usually removed the next day after the surgery.
There are three types of laser prostate surgery. The type of the surgery depends on the size of the prostate, the general health of the patient and the surgeon’s experience and preference.
Photosensitive vapourisation of the prostate (PVP): This utilises a laser of 532nm wavelength, for vaporising the prostate tissue. This laser appears green in colour and hence this surgery is also called as green light laser therapy. The laser of this wavelength is chosen as it is selectively absorbed by the red prostate tissue and poorly absorbed by water. It has the ability to penetrate deeper into the tissue and creates a 1-2 mm zone of coagulation necrosis around the area of vapourisation resulting in little or no bleeding. PVP is used only for vaporization of small prostate glands as use for glands larger than 60cc results in prolonged irritative urinary symptoms, due to its large zone of coagulation necrosis along with its deep penetration power.
Holmium laser ablation of the prostate (HoLAP): This is similar to PVP but uses a holmium laser for vapourisation of the prostate tissue. Holmium laser is absorbed by water and has a lower (0.5mm) penetration depth than PVP, allowing more precise and quicker vapourisation without deeper coagulation thermal injury. Thus it has a lower incidence of complications without any TUR syndrome as compared to PVP. However HoLAP like PVP is also used only for vaporisation of small prostate glands.
Holmium laser enucleation of the prostate (HoLEP): This utilizes the cutting ability of the holmium laser to remove the whole prostate gland by cutting it into small fragments. These fragments of prostate tissue are then grinded within the bladder to easily removable tissue; by using an instrument called a morcellator. HoLEP is equally effective as other non-laser surgical methods and open prostatectomy to remove the prostate. It can even be used for large sized prostates. A major advantage of this procedure over PVP and HoLAP is that prostate tissue cut through this procedure can be sent for pathologic analysis. This is important, as cancer is detected in 7-10 % of the cases sent for pathologic analysis, which was not diagnosed preoperatively.