Conductive Heat: Hot Water-Induced Thermotherapy for Ablation of Prostatic Tissue

Endovenous Laser Application

Introduction: Endoluminal vein treatment is a promising minimal invasive treatment option for peoples suffering from varicose veins. The basic mechanism underlying this procedure is to selectively induce heat in the vessel wall with the result of denaturation of proteins and shrinkage of collagen fibers due to energy application. So far energy could be applied either as RF-current, laser light or water steam. The different approaches to deliver such forms of energies are described.

Methods: Investigations on heat dependent vein tissue effects were performed. The degree of shrinkage and wall thickening due to heat induction was calculated. Tensile test on vein tissue were performed. Investigation using the radial emitting laser fibre in the ox-foot-model under reproducible condition were done and wavelengths dependent tissue reaction were explored.

Results: The experiments clearly demonstrate the degree of the shrinkage of length and diameter, the thickening of the vein wall, as well as the decrease of the elasticity of the tissue. The optical irradiation pattern of the radial emitting laser fiber serves for safe and reproducible energy application directly to the vein wall. Using a laser wavelength with high absorption by the tissue water needs reduced irradiation and irradiance compared to wavelengths with less water absorption. Conclusion: An experimental approach to improve laser application for endovenous varicose treatment is described. Laser parameters and treatment parameters were found which are now under clinical testing. The demonstrated tissue effects may help to find further arguments for clinical findings and sensations described by the patients during follow-up.

The Minimally Invasive Treatments for Benign Prostrate Hyperplasia

The prevalence of benign prostatic hyperplasia (BPH) increases with age, affecting more than 50% of men above the age of 50 to varying degrees. As it enlarges, it compresses onto the urethra causing bladder outlet obstruction. This can cause a spectrum of problems ranging from irritative and obstructive lower urinary tract symptoms (LUTS) to retention of urine with obstructive uropathy. Transurethral resection of prostate (TURP) is the standard for surgical intervention, however with the advent of an ageing population, there is an increasing number of patients who have ischaemic heart disease who require long-term anticoagulation and have multiple co-morbidities that put them at an increased risk of general anaesthesia. This review aims to critically appraise the effectiveness and evidence for use of these minimally invasive techniques.

Both PubMed and Ovid were used to search for randomised control trials (RCT) comparing the various minimally invasive techniques against TURP. In cases where there were no RCTs, the results of the respective trial were compiled. This was later compiled in a summary table.

An effective minimally invasive treatment modality will play a complimentary role to TURP which remains the standard of surgical treatment for BPH. Technologies progressing towards rapid re-creation of prostatic channel, minimal blood loss and non-urethral instrumentation will bridge the divide between pharmacotherapy and surgery.

Thermal ablation of prostate diseases: advantages and limitations

Both benign and malignant conditions affecting prostate gland are very common in elderly men. However, the conventional treatment of these conditions can be associated with significant side effects and complications, and less invasive treatment alternative has been always searched for. Because of the anatomical location and easy accessibility of prostate, many newer treatment modalities using thermal ablation have been applied to the organ. These include not only heating of the pathological tissue but also freezing. Some of such treatment techniques have shown to be effective and safe and been clinically used widely. In this review article, various tissue ablation techniques using temperature change applied to prostate gland are covered. Each procedure's advantages and disadvantages are compared and discussed.

Update of the minimally invasive therapies for benign prostatic hyperplasia

PURPOSE OF REVIEW

The elevated impact benign prostatic hyperplasia has on patient quality of life has determined continuous research into the development of minimally invasive therapies aimed at restoring or preserving a good quality of life. The purpose of this review is to highlight recent developments in the field of minimally invasive treatment of benign prostatic hyperplasia, and to determine their possible impact on everyday clinical practice.

RECENT FINDINGS

Recent publications have described some interesting new therapies and provided data concerning long-term follow up and cost-effectiveness that have been lacking up until now. The review mainly focuses on transurethral microwave thermotherapy, interstitial laser coagulation, transurethral laser ablation, laser prostatectomies (resection and enucleation), transurethral ethanol injection therapy, transurethral electrovaporization, and high-power (80-W) potassium titanyl phosphate laser vaporization.

SUMMARY

Recent developments, new approaches and long-term reports of previously described minimally invasive therapies for the treatment of benign prostatic hyperplasia are presented. Cost-effectiveness studies were also carried out to complete the comparison with standard everyday procedures. Currently, transurethral microwave thermotherapy seems to offer the soundest basis for management of the condition, providing the longest term follow up and the largest numbers of studies completed to date. Among surgical alternatives, holmium laser enucleation has gained ground as an encouraging new approach, being similar to standard transurethral resection of the prostate, but reducing perioperative morbidity with the same long-term results. More randomized comparisons correctly conducted need to be undertaken before an accurate general picture is available for the urologist.