[Cognitive disorders in burnout syndrome].

Objective: To study the impairment of cognitive functions in patients with different stages of the burnout syndrome (BS).

Material And Methods: 78 patients aged 25-45 years (average age 36.9±9.

[Electroencephalographic signs of burnout syndrome].

Objective: To study the electroencephalographic manifestations of the various stages of burnout syndrome (BS).

Material And Methods: A quantitative analysis of the EEG of 131 patients, aged 25 to 45 years, with BS was performed. The control group included 143 people.

In vitro comparison of renal stone laser treatment using fragmentation and popcorn technique.

Objective: To study the effectiveness of two laser techniques clinically used to fragment renal stones: fragmenting technique (FT) and popcorn technique (PT).

Methods: Phantom stones were placed in a test tube filled with water, mimicking a renal calyx model. A Holmium:YAG laser was used for fragmentation using both techniques.

Nd:YAG surgical laser effects in canine prostate tissue: temperature and damage distribution.

An in vitro model was used to predict short-term, laser-induced, thermal damage in canine prostate tissue. Canine prostate tissue samples were equipped with thermocouple probes to measure tissue temperature at 3, 6, 9 and 12 mm depths. The tissue surface was irradiated with a Nd:YAG laser in contact or non-contact mode for up to 20 s, using powers from 5 to 20 W.

Endovenous laser ablation: an experimental study on the mechanism of action.

Objectives: The aim of this experimental study was to investigate the mechanism of action of endovenous laser ablation (EVLA) using an 810-nm diode laser.

Methods: We compared intermittent and continuous delivery of laser energy and studied the absorption of laser light by blood, intravascular temperatures in ex vivo human vein segments using an intravascular thermography catheter and heat dissipation in a model tissue using the Schlieren technique.

Results: Laser light is absorbed by blood and converted to heat leading to coagulation, vaporization and carbonization, and forming an isolating layer at the fibre tip.

Imaging techniques for research and education of thermal and mechanical interactions of lasers with biological and model tissues.

A setup based on color Schlieren techniques has been developed to study the interaction of energy sources, such as lasers, with biological tissues. This imaging technique enables real-time visualization of dynamic temperature gradients with high spatial and temporal resolution within a transparent tissue model. High-speed imaging techniques were combined in the setup to capture mechanical phenomena such as explosive vapor, cavitation bubbles, and shock waves.

Transscleral thermotherapy with laser-induced and conductive heating in hamster Greene melanoma.

The purpose of this study was to investigate the cytotoxic effect of heat as induced by transscleral thermotherapy (TSTT), which may be of interest in the treatment of patients with choroidal melanoma. The aim of TSTT is to heat both the sclera and the tumor up to a cytotoxic temperature of about 60 degrees C. TSTT was performed in hamsters with subcutaneously implanted Greene melanoma covered by a specimen of human donor sclera of thickness 0.

Transscleral thermotherapy: short- and long-term effects of transscleral conductive heating in rabbit eyes.

Objective: To determine the highest safe treatment temperature, at 30- and 60-second exposure durations, for transscleral thermotherapy (TSTT) of choroidal melanoma.

Methods And Design: Transscleral conductive heating was performed in 15 rabbits at 50 degrees C to 70 degrees C for 30 or 60 seconds. The thermal lesions in the ocular fundus were monitored for 4 months with ophthalmoscopic, photographic, and fluorescein angiographic examination.

Transscleral laser thermotherapy of hamster Greene melanoma: inducing tumour necrosis without scleral damage.

The feasibility of using transscleral thermotherapy (TSTT) to induce necrosis of choroidal melanoma without causing damage to the sclera was investigated. Fifty-two subcutaneously implanted hamster melanomas covered by human donor sclera were irradiated for 1 min with an 810 nm laser using a 3 mm spot diameter, with and without cooling of the scleral surface. Immediately after irradiation the temperature of the scleral surface was measured with an infrared camera.

Temperature dependence of thermal damage to the sclera: exploring the heat tolerance of the sclera for transscleral thermotherapy.

Thermal damage to the human sclera in relation to temperature and duration of exposure was studied in order to determine the heat tolerance of the sclera with respect to transscleral thermotherapy of choroidal melanoma. Samples of human sclera were submerged in saline for 10 sec to 10 min at temperatures of 37-100 degrees C. The effects of heat on the shape, weight and size of the samples were studied.

Uniform irradiation of irregularly shaped cavities for photodynamic therapy.

It is difficult to achieve a uniform light distribution in irregularly shaped cavities. We have conducted a study on the use of hollow 'integrating' moulds for more uniform light delivery of photodynamic therapy in irregularly shaped cavities such as the oral cavity. Simple geometries such as a cubical box, a sphere, a cylinder and a 'bottle-neck' geometry have been investigated experimentally and the results have been compared with computed light distributions obtained using the 'radiosity method'.