الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Although TURP is considered a reference standard in surgical therapy of BPE, it is associated with a certain morbidity, mainly caused by perioperative bleeding requiring transfusion or reintervention and irrigation fluid absorption (TUR syndrome). Therefore, a growing number of several laser devices have been introduced in the last 2 decades to overcome the complications of TURP and OP while striving to achieve comparable functional results. Because the wavelength of the Nd:YAG laser (1064 nm) displays a low absorption in prostatic tissue, it creates deep coagulation necrosis without any instant tissue removal displaying minimal blood loss. Treatment of BPE with the Nd:YAG laser is therefore characterized by long postoperative catheterization times because the treatment success can take several weeks to set in. Furthermore, several studies have reported a retreatment rates of over 20% after 2 years. In contrast to the Nd:YAG laser, the wavelength of the Ho:YAG laser (2140 nm) is highly absorbed in prostatic tissue, leading to instant vaporization without a considerable coagulation necrosis. Because simple ablative techniques proved to be rather time consuming, the use of the Ho:YAG laser for BPE treatment evolved to the more time-efficient techniques of holmium laser resection of the prostate (HoLRP) and holmium laser enucleation of the prostate (HoLEP). All described techniques display a low perioperative complication rate and produce durable results with low retreatment rates in the follow-up. However, the learning curve for the more time-efficient techniques is rather steep, limiting the widespread use of these techniques. The wavelength of the widely used KTP laser (532 nm) offers above all a good haemostasis because it is strongly absorbed by haemoglobin. The laser energy is delivered via a side-fire fiber and produces instant vaporization of prostatic tissue. The technique is easy to learn, is associated with low perioperative morbidity, and produces results similar to those of TURP. However, only limited long-term data are available, and treatment times are rather long because tissue vaporization is time consuming, limiting the patient collective to those with smaller glands. The thulium laser is a new high performance laser using similar 2 µ (2,000 nm) wavelength to the holmium laser but is delivered as a cw rather than pulsed. Rapid absorption in water, short penetration depth and incisional and haemostatic properties are similar to those of the holmium laser, but the cutting is much smoother owing to the CW mode. In prostate surgery, the CW 2 µ thulium laser has been used for resection of the prostate, a technique, which is similar to HoLRP, i.e., it is effective and safe but time-consuming and suffers from the large amount of about two thirds of tissue lost to vaporization, and enucleation of the prostate which is performed identically to HoLEP. A diode laser working on a wavelength of 980 nm has been introduced lately to overcome the described problems of the established laser devices. Because this wavelength offers the highest simultaneous absorption in water and haemoglobin, it is postulated to combine high tissue ablation capacity and good haemostasis. Further advantages of the diode laser over KTP and Ho:YAG laser devices include a significantly lower energy consumption and the absence of a required high-voltage connection, which improves mobility of the laser generator. Currently, data on HoLEP and to a minor extent on PVP with the KTP or LBO laser offer a high grade of scientific evidence that these therapeutic modalities are recommendable alternatives to TURP and OP. Thulium laser ablation and diode laser vaporization of the prostate are challenging results of HoLEP or PVP, but further trials are needed to evaluate their clinical value. As a conclusion, up till now HoLEP can be considered as a new gold standard to which any new modality in treatment of BPE should be compared.