Elsevier

European Urology

Volume 61, Issue 2, February 2012, Pages 317-325
European Urology

Review – Benign Prostatic Obstruction
Laser Treatment of Benign Prostatic Obstruction: Basics and Physical Differences

https://doi.org/10.1016/j.eururo.2011.10.009Get rights and content

Abstract

Context

Laser treatment of benign prostatic obstruction (BPO) has become more prevalent in recent years. Although multiple surgical approaches exist, there is confusion about laser–tissue interaction, especially in terms of physical aspects and with respect to the optimal treatment modality.

Objective

To compare available laser systems with respect to physical fundamentals and to discuss the similarities and differences among introduced laser devices.

Evidence acquisition

The paper is based on the second expert meeting on the laser treatment of BPO organised by the European Association of Urology Section of Uro-Technology. A systematic literature search was also carried out to cover the topic of laser treatment of BPO extensively.

Evidence synthesis

The principles of generation of laser radiation, laser fibre construction, the types of energy emission, and laser–tissue interaction are discussed in detail for the laser systems used in the treatment of BPO. The most relevant laser systems are compared and their physical properties discussed in depth.

Conclusions

Laser treatment of BPO is gaining widespread acceptance. Detailed knowledge of the physical principles allows the surgeon to discriminate between available laser systems and their possible pitfalls to guarantee high safety levels for the patient.

Introduction

Transurethral resection of the prostate (TURP) and open prostatectomy are considered the gold standard in the treatment of benign prostatic obstruction (BPO) [1], [2]. However, considerable morbidity is associated with both procedures. TURP is associated with low morbidity in smaller prostates, but problems increase with rising volume [1]. Similarly, open surgery for high-volume glands is coupled with associated morbidity [2], [3]. Several laser-based minimally invasive treatment options have been introduced to achieve symptom improvement with reduced morbidity. Although multiple lasers are in use, confusion exists about laser–tissue interaction. Several physical aspects, such as the best possible wavelength and the way of applying laser energy, remain to be clarified.

This structured review is based on the outcome of a European Association of Urology Section of Uro-Technology (ESUT) expert meeting involving physicists, technicians, and urologists focussing on the basic science of laser radiation generation, transmission, and laser–tissue effects. A systematic comparison of the physical backgrounds of the various devices was performed.

Section snippets

Evidence acquisition

This paper is based on the second expert meeting on laser treatment of BPO organised by the ESUT. In addition, we performed a systematic literature search using the Medline, Embase, and PubMed databases. Inclusion criteria were meta-analyses, randomised controlled studies, reviews, and controlled cohort and experimental studies providing information on basic laser science and application for treatment of BPO. In addition, we included the expert opinions of participating urologists, physicists,

Generation of laser radiation

Laser is an acronym for “light amplification by stimulated emission of radiation.” The envelope “light radiation” shows that escaping energy is simply light of a defined wavelength and direction. This light is created by a quantum mechanical principle of “stimulated emission” of radiation of an excited laser medium (active media: gas, crystal, glass, dye). Excitation of the laser medium can be achieved by various principles (eg, excitation by photons from a flash lamp). Some of the excitation

Conclusions

Although laser treatment of BPO has gained widespread acceptance, controversy continues about the physical properties and background of laser radiation generation and laser–tissue interaction. Knowledge about the effects of different wavelengths on the targeted tissue is mandatory. The term laser prostatectomy should only be mentioned in combination with laser type or wavelength. Available laser systems have proven clinical efficacy comparable with the well-established gold standard. Knowledge

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