ENCEPHALOGRAPHY (Greek enke-phalos a brain + grapho to write, represent) — a method of a X-ray or radio isotope inspection of a brain.
Rentgenol. the research of a brain is conducted in the way vvede-
a niya in likvorny spaces of gas (see Pnevmoentsefalografiya) or high-atomic radiopaque substances (see Ventrikulografiya). In a crust, time these researches apply less often in connection with development of a computer tomography of a brain (see the Tomography computer).
The radio isotope encephalography (a synonym a gamma encephalography) is based on ability of a number of radioactive connections to collect in fabric of a tumor or others patol. educations (abscesses, centers of hemorrhages, etc.). As radio of pharmaceutical drug (see) most widely use 99tts — the pertekhne-Tat, to-ry enter intravenously for 1 — 3 hour before carrying out radiometry (see).
Registration and visualization of distribution of radio pharmaceutical drug (RFP) in the head are carried out by means of the gamma camera providing the image (gamma topogram) of body in the form of the photo or on the screen of the multichannel analyzer (see. Radio isotope diagnostic units). Complete idea of distribution of RFP in tissues of the head can be gained only by means of a multiprojective research. The following projections are most accepted: front and back straight lines, right and left side and parietal.
At absence patol. changes on the gamma topogram (stsintigramma) after introduction 99I» Tc — the pertekhnetata accurately is defined the image of soft tissues and bones front and a neurocranium, mucous membranes of an oral and nasal cavity, and also the sialadens accumulating RFP in a significant amount. Normal the brain on the gamma topogram looks as area with the smallest level of accumulation of RFP.
In the presence of intracranial volume education on the gamma topogram the center of accumulation of RFP comes to light, on outlines to-rogo it is possible to judge localization, the sizes and prevalence of process (fig).
Diagnostic efficiency radio isotope E. at tumors of a brain to a great extent depends on them gistol. structure and sizes. Meningiomas possess a high level of accumulation of RFP entered into an organism (see the Meningioma),
to-rye come to light in 95% of cases. Glioblastoma (see Glioblastom) and metastatic tumors of a brain are found in 80% of cases. Cranyopharyngiomas (see the Cranyopharyngioma), tumors of a hypophysis, an epidermoida are defined no more than in 10% of cases. Tumors of a brain less than 1,5 cm in size in the diameter do not come to light even on condition of high accumulation of radionuclide by them.
Fig. Gamma topograms at the malignant glioma of a brain which is located in parietotemporal area: in right side, back direct and parietal projections the center of pathological accumulation "tts is visible (the center is specified by shooters).
Radio isotope E. it was informative and at nek-ry not tumoral defeats of c. N of page — abscesses (see Abscess), subdural hematomas, arteriovenous aneurisms (see Aneurism of vessels of a brain).
Radio isotope E. gives information not only on existence patol. process, the sizes and localization of defeat, but also allows to make the conclusion about its character and the nature. The radioizotrpny semiotics at tumors is developed various gistol. structures, hemorrhages, abscesses, the centers of a contusion, edge gives the grounds to carry out accurate differentiation of these processes.
Radio isotope E. apply as a selection method at polyclinic inspection of persons with suspicion on volume formation of a brain and at preoperative inspection of patients to specification of size, a form and topography of a new growth in a brain. Ample opportunities for E. the emission computer tomography represents (see).
Bibliography: Badmayev K. N. and
Smirnov R. V. Radionuclide diagnosis and radiation therapy of diseases of a nervous system, M., 1982; Tumours of a brain, under the editorship of A. I. Arutyunov, page 82, M., 1975; Petelin JI. Page, Kasatkin Yu. N. and Nose island and S. M. Radio isotope diagnosis of diseases of a brain, M., 1976; M an i s e at M. of Nuclear medicine, p. 15, L. and. lake, 1980. See also bibliogr. to the Art. of Ventrikulografiya, Pnevmoentsefalografiya. F. M. Lyass.