From Big Medical Encyclopedia

RADIOPAQUE SUBSTANCES (a synonym contrast agents) — the means used for visualization of the invisible or badly seen at usual X-ray inspection bodies or perigastriums. R.'s effect of century is based on significant increase in a difference of absorption of x-ray emission by the studied anatomic educations and the fabrics surrounding them.

On physical properties of R. of century divide into X-ray positive (X-ray positive) and X-ray negative (X-ray negative). Carry the liquid and solid matters having high molecular weight and absorbing x-ray emission in much bigger degree, than tissue of a body to X-ray positive. Liquid X-ray positive drugs are most widely used. Century carry gases to X-ray negative R., to-rye absorb x-ray emission few: air, nitrous oxide, carbon dioxide. Their introduction leads to emergence of the transparent background promoting identification patol. educations.

From X-ray positive R.' group of century most widely use the drugs containing barium sulfate (see. Barium ), and the drugs containing iodine (see).

Drugs of barium of sulfate are the main for a research went. - kish. path. For this purpose apply usually water suspension of barium of sulfate containing from 6 to 10 g of drug on 10 ml of water. In medical practice only chemically pure sulfate of barium, free of any impurity (Barii sulfas pro roentgeno) is used. For crushing of particles and homogenization of a suspension it is processed by means of the mixer or ultrasound. Abroad also the drugs of barium of sulfate containing the substances which are slowing down sedimentation of solid particles of a suspension are produced (e.g., miksobar, baritol, falibarit, a microtrust, etc.). From them the substances impacting them relish and a smell of fruit or berries support Nek-rye. Such drugs are used by hl. obr. in children's practice. At a research of a large intestine by means of an opaque enema for improvement of distribution of barium of sulfate on a mucosal surface of a cover sometimes add to a suspension of this drug tannin, 4 — 5 g on 1 l of a suspension. At a research of a large intestine and stomach with the same purpose in quality of additives to a suspension of barium of sulfate it is possible to use ovalbumin, honey, arabic gum, a root of a mallow. For acceleration of advance on a small bowel the suspension of barium of sulfate is cooled to t ° 8 °.

Iodinated drugs represent the most extensive group P. of century. Among them drugs of organic compounds of iodine and the iodated oils are almost important.

From organic compounds of iodine as R. century use derivatives nek-ry aromatic to - the t (the benzoic, fenilpropionovy, adipinic, etc.) containing atoms of iodine. Century are among such R., e.g., derivatives triyodbenzoy-ache to - you — triyotrast, triombrin (see), Urotrastum, yotalamovy to - that (Acidum iotalamicum) and its salts, released abroad under various names, e.g. Konrey (Sopgau; synonym of Contrix), etc. To derivatives triyodbenzoyny to - you are also Iodamidum (Jodamid; synonym of Acidum ametriodicum), to-ry is issued in the form of 65% of solution of N-methylglucamine salt under the name «Iodamidum-300» (Jodamide-300; synonym: Neo-Uromiro, Uromiro, etc.) and 80% of solution of mix of sodium and N-methylglucamine salts under the name «Iodamidum-380» (Jodamide-380). The century specified by R. are applied to contrasting of blood vessels and urinary tract.

Derivatives triyodfenilpropionovy to - you — yopanoyevy to - that (Acidum iopanoicum; synonym: Jopagnost, Cholevid, Cistobil, etc.), sodium yopodat (Natrii iopodas; synonym of Biloptin, Oragrafin-Sodium, etc.) and calcium yopodat (Calcium iopodate; a synonym of Oragrafin-Calcium) use for peroral holegrafiya (see). With the same purpose applied derivative diyodoksifenilpropionovy to earlier - you Bilitrastum (see).

For an intravenous holegrafiya use to derivatives triyodadi-pinic to - you Bilignostum (see), and also bilivistany (Bilivistan; the synonym of Biligram), to-ry represents solution of mix of sodium and N-methylglucamine salts yoglikamovy to - you.

As R. century for miyelografiya (see) apply generally myodil (Myodil; synonym: Iofendylatum, Panto-paque, etc.), the representing oil solution of mix of ethyl ethers of two isomers yodfenilundekanovy to - you and containing apprx. 30% of integrally connected iodine.

Except the listed above drugs from organic compounds of iodine, century belongs to R. propilyodon (see), and also nek-ry other derivatives diiodine - pyridoneacetum to - you (e.g., Hytrast, Per-Abrodil BR), used for bronchographies (see).

Century from group of the iodated oils carry the drugs received by iodination of nek-ry vegetable oils to R. (poppy, sesame, surepkovy). Domestic drug concerns to this group P. of century Iodolipolum (see) and its foreign analogs (e.g., Iodatol, Lipiodol, etc.), to-rye apply to a bronchography, metrosalpingografiya (see) and fistulografiya (see). It is possible to carry drugs of diiodstearates to this group, napr, liquid and superliquid lipiodolum (Lipiodol fluide, Lipiodol ultrafluide), etiodol (Ethiodol), etc., used for limfografiya (see) and sialografiya (see), and also drugs monoiodine-stearates, napr, duroliopak (Duroliopaque), applied for miyelo-and ventrikulografiya (see).

Century (air, nitrous oxide, carbon dioxide) use X-ray negative R. usually for contrasting of an abdominal cavity, retroperitoneal space, a mediastinum, went. - kish. path.

Sometimes at a research zhel-kish. a path and a bladder at the same time apply X-ray positive and X-ray negative R. century (a so-called double contrast study).

For the combined rentgenol. and radionuclide researches apply also radioactive R. century (e.g., at a limfografiya and nek-ry others).

Century it is contraindicated to persons to enter iodinated R. with hypersensitivity to iodine. In offices where researches with use of such drugs are conducted, there has to be a set of antiallergic means and tools for their introduction.

Bibliography: Sviridov N. K. Use of oil X-ray contrast agents at new methods of a research, Klin, hir., No. 4, page 69, 1976; Xie of r-gays P. V., Sviridov N. K. and Szymanowski H. JI. X-ray contrast means, M., 1980, bibliogr.; Modern X-ray contrast agents, under the editorship of JI. S. Rozenshtraukh, M., 1969 — 1972; In and r k e R. Rontgenkontra-stmittel, Lpz., 1970; Radiocontrast agents, contrib. G. Carrasquer a. o., v. 1 — 2, Oxford a.o., 1971.

L. S. Rozenshtraukh.