The first substantiated medical report came from a doctor who took part in Napoleon´s invasion of Russia, and made notes in 1812. They discuss the phenomenon of limitation and removal achieved through freezing - a technigue which the doctor made use of while having to amputate numerous limbs at that time. Since that time cryosurgery has gained many adherents in all fields of medicine. It is enough to say that cryosurgery is based on the phenomenon of nitrification or crystallization of water within a cell or intercellular spaces. Intercellular crystallization leads to the death of a cell. After thawing a cell can still be the same shape but its cytoplasm and remaining elements of internal structure are destroyed (1).

The purely mechanical process is followed by strong cytochemical and immunobiological reactions having an influence on an extensive, controlled destruction of previonsly-frozen cells and tissues (2).

Cryosurgery has an advantage over electrocoagulation in that it is painless and less aggressive. It is possible to destroy tissue situated externally without damaging deeper structures, which is particularly important when it comes to treating epithelium and epidermis disease. The important feature of cryodestruction is the healing process. External damage to the epithelium makes easy regeneration and multiplication of adjacent tissues possible. The resultant scars are thin and delicate and they do not deform the surface. The virtue of cryosurgery is the possibility of combining it with other surgical techniques.

The aim of the study is to present crucial therapeutic benefits resulting from using cryodestruction in the most frequently - encountered laryngologic diseases in children.

The cryoapplication technique was introduced in our department in 1998. In the initial phase of application of the therapy we used liquid nitrogen as a low temperature carrier.

After numerous negative results we gave up cryodestruction using a nitrogen douche due to the size of tissue lesions, including the depth of the demarcational tract, the inability to regulate the temperature of the liquid nitrogen stream, and imprecise application. Since 1999 we have introduced into cryotherapy low temperature generators with diverse cryoapplicators, in which nitrous oxide is athecarrier of temperatures as low as - 80°C.

Cryoapplication using the above-mentioned devices allows:

- precise selection of the contact surface of the applicator,

- the use of an applicator introduced beneath tissue surfaces,

- flexible time of exposure,

- programming cyclic freezing,

- regular check on the action of the applicator,

- accurate measurement of temperature,

- closed circulation of gases.

The above parameters correspond very well with the anatomic conditions in children´s laryngology. We divided our patients into two main groups and into two control groups. Fifty-seven patients with diagnosed vascular changes confirmed by histopatologic examination were qualified for the first group. Thirty-one patients, with similar vascular changes treated with different techniques including injecting Varigocit and the Veoblastina concentrated solution of sodium chloride, x-ray irradiation, light surgery were qualified for control group I.

Therapeutic results and the time in which they were achieved were compared between both groups. In examination group II, 127 patients were treated for pharyngeal tonsillar hypertrophy. Surgery was performed with the aid of a cryodestruction technique using two different cryoapplicators and an exposure time of 3 x 45 seconds before adenotomy and 2 x 45 seconds after the removal of adenoidal tissue. Control group II consisted of 61 children with pharyngeal tonsil hypertrophy who were operated on without using cryapplication.

In both groups, the biochemical parameters of the blood before and after surgery were compared, as well as the volume of blood flowing out of the damaged vascular placenta during surgery and in a convalescence period, as well as subjective symptoms submitted by the children.