Argon and krypton lasers are widely used in medicine. The paper contains information on ion lasers parameters and a description of diagnostic and therapeutic systems containing ion lasers used in different branches of medicine: ophthalmology, dermatology, micro-surgery, and photodynamic therapy of tumors.

This paper presents the current state of technology and technique of solid-state lasers, especially of those generating radiation within the range 1 divided by 3 micrometers , designed for medical applications. Rapid development, both in the field of scientific research and in a number of new constructions of lasers and laser systems for medical applications which have appeared during recent years, causes a necessity of their systematization in respect to the expected affects of interaction between a laser radiation and tissues, and thus also therapeutic effects of the particular types and kinds of lasers applied or planned for application in medicine. This elaboration presents the limited, chosen group of laser devices and lasers themselves, namely solid-state lasers, considering especially the new laser media, generating in the infrared range and semiconductor lasers of the particular high power -- of the order of several watts of radiation -- in respect of the expected effects, connected with their medical applications. Considering the specific features of each kind of lasers -- the semiconductor lasers and with the classic resonator configuration ones -- despite their classification among solid-state lasers, in this elaboration they are treated separately in spite of the present constructions of laser medical equipment and the laser devices supplemented each other.

In recent years, a growth of interest in the medical application capabilities of diode laser applications can be observed. Many of their unique qualities have made or may soon cause the diode laser to replace other commonly used lasers or devices in many medical applications. Some diode laser types offer totally new perspectives and treatment possibilities. The requirements made on diode lasers for three chosen medical applications, low-energy level laser therapy, photodynamic therapy of tumors, and surgery, have been presented in this paper paying attention to the choice of diode laser parameters, i.e., power of radiation, wavelength, spherical beam spectrum, utilization of the right probes, working mode (impulse or continuous wave), and the ability to regulate power output, energy dose, frequency, and biological tissue exposure time. A comparison between diode laser parameters and other lasers used to date in the applications mentioned above also has been presented.

The paper presents a description of a construction of the ophthalmological set LH-58 with the holmium laser. Results of preliminary medical tests of eye lens curvature correction carried out by means of this set are given.

The ophthalmological coagulator LKP-1500 with the semiconductor laser is presented. The LKP-1500 set has been compared with other such type sets. The elaborated device has been tested under clinical conditions.

The laser coagulator is assigned to the coagulation of an eye retina. It has been built on the basis of semiconductor cw laser, SDL-2482 P1 type. The laser is integrated with the monitoring photodiode, thermistor, and thermoelectric cooler. The electronic system ensures a continuous work (cw) and pulse work of the coagulative laser. For the continuous work, the time of laser operation depends on how long the operator presses a pedal. Exposure duration is displayed at the time-meter. The pulse operation enables previous setting of pulse duration. Time of laser switch on can be regulated from 0 to 5 s with the resolution of 0.1 s. The output laser power is regulated continuously from 1 mW to 3 W and it is displayed at the power meter display. The laser controller is equipped in the series of systems protected against the exceeding of permissible work conditions.

An endocoagulator with an ion argon laser designed and manufactured at Warsaw Technical University is described in this paper. Technical data and a short description of this unit are given.

The task of the laser methods of glaucoma treatment used up to the present day is to reduce the intraocular pressure. They are the modification of the surgical procedures. The radiation of the laser is the tool that enables us to perform the procedure in a more precise and safe manner. Most of the procedures are ambulatory, thus, making the expenses for the treatment lower. The results of the treatment are satisfactory, and in many cases, enable the patient to avoid surgical procedures. In practice, for the anti-glaucoma procedures the argon laser, YAG Nd⁺³, of free generation, and Q-switch, Holm laser, are being used. The perspectives to use other lasers also exist.

Clinical effects of iridectomy performed by the use of laser Yag Nd⁺³-Q-switch on 38 patients treated for intra-ocular pressure increase were analyzed. In 32 cases primary glaucoma was diagnosed. In 11 cases secondary glaucoma was caused by pupil blocking. Pressure normalization was obtained in 27 cases (71%). In the remaining 11 patients pressure decreasing was acquired but at the same time administration of antiglaucoma medicines was indispensable. Time of observation took from 4 weeks to 3 years.

In our experimental work we present the use of hematoporphyrin derivative photodynamic therapy (HpD-PDT) in the treatment of melanoma. Eighteen eyes of rabbits were incubated intracamerally with amelanotic Greene melanoma tissue. The technique involves the administration of HpD and photoactivation of tumor with red light (630 nm) to achieve selective destruction of cancer cells. After photoradiation the tumor showed blanching and shrinkage, we could also observe the tumor vasculature damaged. Successfully treated tumors had large areas of necrosis with severely damaged blood vessels in histopathological examination. Results indicate that HpD-PDT is a very promising modern modality offering a new method of melanoma treatment.

Argon laser was applied in 172 patients with various vascular disorders and epidermal nevi. The best therapeutical results were obtained in facial telangiectasia and in cavernous hemangiomas, in which there was a complete or almost complete regression. In capillary facial hemangiomas in 49 patients (79%) clearing of 50% to 75% was obtained, and in epidermal nevi the full regression was in 4 (44%) of the cases, and 50% regression in 4 (44%). In telangiectasia of the lower limbs the results were not satisfactory. We stress that cavernous, and capillary hemangiomas, as well as facial telangiectasia are an indication for the argon laser therapy.

Nd:YAG laser therapy was applied in 43 adults and 7 children with condylomata acuminata. The dosages of radiation and the procedures depended upon the extent of the lesions. A complete clearing occurred in 94% of the cases, and in 6% there were relapses. The procedure should be performed in children under general anesthesia, and in adults under local anesthesia since radiation with Nd:YAG laser is rather painful. The healing was uneventful, with no scarring, and the results appear to be better than obtained with cryotherapy which gives 80.8% of complete clearing.

The effectiveness of two preparations used as photosensitizers in the photodynamic method for neoplasm treatment was examined. The material consisted of Balb/c strain mice with transplanted lung sarcoma, Sarcoma L₁. Arginine derivative HpDArg₂ (hematoporphyrin derivatives -- arginine) and PP(Phen₂Arg₂, i.e., 1-arginine di(N- phenylalanyl) protoporphyrinate, were used as photosensitizers. Animals were administered the photosensitizer in a dose of 10 mg/kg body weight. After 24 hrs they were irradiated with He-Ne laser; total energy of 150 J/cm² was applied in three portions of 50 J/cm² each, at 24-h intervals. The results showed that PP(Phen)₂Arg₂ destroyed Sarcoma L₁ much more effectively than the conventionally used mixture of hematoporphyrin derivatives, customarily named HpD.

In this paper the dimerization constant of pure hematoporphyrine was established using absorption method and then fluorescence quantum yield ((phi) ) was calculated as a function of monomeric fraction ((alpha) ). It was our objective to formulate an equation describing the relationships between (phi) , (alpha) and ratio of monomer to dimer molar absorption coefficients ((epsilon) _M/(epsilon) _D), at a given wavelength. (phi) was also studied as a function of pH value and polarity. A 3-D stack fluorescence plot was also constructed and the possibilities of practical application of the fluorescence effect to the visualization of areas with absorbed are presented.

In this paper a unit with two krypton lasers is described. This apparatus is designed to be used in photodynamic diagnosis and therapy of tumors in ophthalmology. Some technical data are given.

The paper presents the LPP series of biostimulative systems which are based on semiconductor lasers. These devices are characterized by the following properties: microprocessor controlling, modulus structure, and three wavelength of operation.

The author presents the initial comparative investigations on treatment with laser beam, diadynamic current, and combined operation of diadynamic currents and classic massage. The investigations were performed in three groups on 78 patients. The obtained results indicate great therapeutic effectiveness of laser biostimulation, better than in other treatments and a larger scope of indications for treatment with that method. According to the modified Laitinen's scale the obtained improvement was from the range of two points, corresponding to strong pain, to 0.3 points, almost complete regression of the pain.

The application of laser light and laparoscopy attenuates operative trauma owing to the use of small incisions for introducing the trochars necessary for conveying the surgical instruments and fiber optics which allow for precise cutting and coagulation of small vessels under control of the image on a TV monitor. The present, most remarkable development of laparoscopic surgery is due to the fascination of physicians and patients by this procedure. The method enables the physician to operate with great precision and to take advantage of the most recent attainments of electronics and laser technique, as well as of his own ability. The patients profit by attenuation of postoperative pain, limitation of the probability of infection, reduced blood loss, decreased number of postoperative complications, shortening of the hospitalization period, and rapid return to physical fitness and work.

A CO₂ laser device was used for treating cervical lesions in 1574 patients. Of the total, 163 were diagnosed as CIN. Patients were selected for the study as a result of mass screening during the period from 1988 to 1992 of Bialystok Province, Poland. Treatment of cervical lesions with laser proved to be effective. In the author's opinion it is an essential step in preventing cervical malignancy.

The paper presents the LL-59 set with Nd:YAG laser used for otorhinolaryngological operations. The set enables the user to apply a new treatment method in otorhinolaryngology. The interaction effects between radiation and tympanic membrane are described.

Up to now, among different kinds of lasers an argon laser is mostly used for otosclerosis. Exposure conditions at use of the laser beam are still not well defined. In order to achieve the optimum conditions a series of experiments has been made. Obtained results are presented in this paper.

Some aspects of optical radiation detection in biology experiments are presented. Dependencies occurring during low-energetic interaction of laser radiation as well as a high energetic one of 2 divided by 3 micrometers range in biostimulated processes are discussed. Anomalous transmission of radiation of this spectral range through tissues was proved. Some measurement aspects of photodynamic tumor therapy are shown.

The effect of infrared laser radiation on specific electrical conductivity and relative permittivity of blood in experimental animals was estimated. The experiment was carried out on 30 male guinea pigs weighing 280 - 320 g. Fifteen animals composed a group irradiated with laser, the other 15 animals made up a control group in which no irradiation was made. A semiconductive laser generating infrared radiation (wavelength -- 904 nm, frequency -- 800 Hz, pulse duration -- 200 ns, mean power -- 8.7 mW) was used. The right infracostal region of the animal was irradiated 3 minutes daily for 15 consecutive days. After the end of the experiment in the obtained blood the values of impedance and phase shift angle were measured by means of impedancemeters in the frequency range from 100 to 10,000 kHz. The values of specific electrical conductivity and relative permittivity were calculated on the basis of obtained data. A distinct increase of specific electrical conductivity and decrease of relative permittivity were obtained in the blood of irradiated animals at all frequencies, as compared to the controls. No changes in relaxation frequency were noticed between both groups. On the basis of obtained data it is possible to confirm a distinct effect of low-energy laser radiation on dielectric properties of blood in experimental animals. Since the observed changes in (chi) and (epsilon) ' occurred in (beta) -dispersion region, they might therefore be attributed to the charging of cell membranes in erythrocytes.

The effect of infrared laser radiation on viscosity of serum and blood in experimental animals was investigated. The experiment was carried out on 30 male guinea pigs weighing 280 - 320 g. Fifteen animals composed a group irradiated with laser, the other 15 animals made up a control group in which no irradiation was made. A semiconductive laser generating infrared radiation (wavelength -- 904 nm, frequency -- 800 Hz, pulse duration -- 200 ns, mean power - - 8.7 mW) was used. The right infracostal region of the animal was irradiated 3 minutes daily for 15 consecutive days. After the end of the experiment in the obtained blood and serum the measurement of hematocrit and rheologic examination was made in the temperature of 310 K. The estimation of viscosity of whole blood was made by means of low-gradient viscosimeter `low shear,' for shearing velocities: D₁ equals 0.116 s^-1 and D₂ equals 4.59 s^-1. The viscosity of serum was estimated using Ubbelohd's microviscosimeter. A significant increase of whole blood viscosity measured for shearing velocity D₁ was obtained in irradiated animals as compared to the controls. No statistically significant differences in viscosity of whole blood at clotting speed D₂, viscosity of serum and hematocrit were observed between both groups of animals. The obtained data prove a distinct effect of low-energy laser radiation on rheologic properties of blood in experimental animals. The increase of whole blood viscosity, observed only at low shearing velocities, is probably related to the changes of structural and functional properties of cell membranes of erythrocytes resulting in a decrease of aggregation.

The effect on their behavior of chronic exposure to infrared laser radiation applied to the skull of rats was evaluated. The experiment was carried out on 20 Wistar white male rats. A semiconductive infrared laser (wavelength -- 904 nm, frequency -- 100 Hz, pulse duration -- 10 ns, mean power 10 mW, energy density 1.5 J/cm²) was used. A skull fornix of rats was irradiated with use of multidiode probe, 10 minutes daily for 14 consecutive days. A locomotor activity was determined in the `open field' test. Simultaneously, an exploratory activity was examined in the `hole' test. Space memory was determined by means of a water maze test. Afterwards, an irritability was investigated by means of the score of Nakamura and Thoenen. The evaluation of behavior was made 24 hours after a single irradiation, at the 7th and 14th day of repeated everyday irradiation and then at the 7th and 14th day after the end of the cycle of irradiations. Obtained data show that low-energy laser radiation does not affect the rats central nervous system, resulting in persistent changes of behavior.

The influence on pain perception of acute and chronic exposure to infrared laser radiation applied to the skulls of rats is examined. The experiment was carried out on 60 Wistar white male rats. A semiconductive infrared laser (wavelength -- 904 nm, frequency -- 100 Hz, pulse duration -- 10 ns, mean power 10 mW, energy density 1.5 J/cm²) was used. A skull fornix of rats was irradiated with use of a multidiode probe 10 minutes daily for 14 consecutive days. The pain perception was determined by the latency of foot-licking or jumping from the surface of a 56 degree(s)C hot plate. The measurements were made immediately before irradiation, at 1, 5, 10, 15, 20, 25 and 30 minutes after irradiation, and then every 15 minutes until 120 minutes after irradiation. The pain perception is estimated immediately after irradiation, 24 hours after exposure at the 7th and 14th day of irradiation as well as at the 7th and 14th day after the last irradiation. A pretreatment with Naloxone (1 ml/kg of body weight i.p.) was made in a part of the animals in order to evaluate the involvement of the opioid system in the observed effect. Obtained data show that low-energy laser irradiation affects the pain reactivity of rats. The inhibition of the analgesic effect of laser irradiation by the antagonist of opioids -- Naloxone -- and also the prolonged character of this action as a result of direct irradiation of the skull indicate the involvement of the opioid system in the occurrence of laser-induced analgesia.

A high number of osseous diseases, particularly of the backbone and hip-joint regions, result in a need for their overall treatment and prevention. Two basic treatment methods are used: physical exercises at an early stage of the illness, and surgical treatment in an advanced stage. Recently, in operational treatment of coxarthrosis the elements of the joint (acetabulum and capitellum) were replaced by their artificial counterparts, despite some drawbacks and unknowns related to this kind of treatment. In order to check the effectiveness of this treatment and to eliminate its drawbacks we have tested the joint by means of speckle photography method. The objective of this paper is an attempt to evaluate stress and displacement distributions in a system consisting of artificial acetabulum and capitellum and a natural bone in order to determine an optimum fitting of artificial acetabulum and capitellum and a natural bone in order to determine an optimum fitting of artificial elements that guarantees uniform distribution of stresses corresponding to anatomical and physiological parameters of the hip-joint. Speckle photographs have been analyzed point by point with the help of the algorithm for striped images processing.