SU1483378A1 - Method of radioisotope measurement of tidal lung volume - Google Patents

Abstract

This invention relates to medicine, in particular to methods for studying residual lung volume. The purpose of the invention is to reduce the research time and simplify the process by measuring the radioactivity of the air-xenon mixture (XE ¹ 33) fraction with the maximum inhalation of the fractions remaining in the lungs and leaving them after the maximum expiration.

Description

The invention relates to medicine, in particular to methods for examining respiratory organs, and can be used in radioisotope diagnostic laboratories.

The aim of the invention is to reduce the research time and simplify the method.

Example 1. A collimated Xenon radiographic sensor is oriented on the patient's chest in such a way that both patient's lungs fall into his field of vision. The patient is connected through a mouthpiece to a spirograph filled with an air-xenon () mixture (2 Mbc / l of air). The movement of the tape recorder mechanism is included. While the patient is breathing room air, set the pen of the recorder to the zero line. After maximum exhalation, the patient is breathing into a spirograph using a rotary valve. The subject produces -

the first maximum entry of the air-xenon mixture and holds your breath for 10 s. At this time, the amplitude of the radioactivity level in the lungs (A) is recorded on the recorder tape. The patient then makes the maximum exhalation and again holds the breath for 10 s. This time is quite enough to obtain accurate information in radiography from the time constant used by us of 2 s. After exhalation, the amplitude of the level of radioactivity in the lungs decreases and reflects only the level of radioactivity remaining in the lungs (A /). The radioactivity fraction of the first maximum inspiratory discharge from the lungs after maximum expiration (A &) is equal to the difference A-A. The result is the following data: the vital capacity of the lungs (VC) in the subject is 3 liters. The amplitude of the radiogram of the first (A) maximum inspiration is 5 cm. The amplitude of the radiogram after

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with

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the maximum expiration (A /) is 2 cm. Therefore, the amplitude of the radiogram reflecting the fraction of radioactivity leaving the lungs after the maximum expiration of radioactivity (Hell) is equal to A-A see. OOL (residual lung volume) ZEL x (A n: A, j ) 3 liters x 2 cm:: 3 cm 2 liters.

Example 2. A collimated Xenon type radiograph sensor is oriented on a spirograph bell filled with an air-xenon mixture. The subject is connected to the spirograph through the mouthpiece. The movement of the tape recorder mechanism is included. While the patient breathes room air, set the pen of the recorder on the zero line in the upper part of the chart tape. B, the bell of the spirograph should contain an air-xenon mixture in a volume exceeding the vital capacity of the subject (almost 6-7 liters). The zero mark on the radiogram actually corresponds to the signal from this volume of radioactivity in the bell. After the maximum exhalation, the patient is pivoted with a rotary crane to breathe into the bell and ask him to take a maximum inhale with a subsequent breath hold for 20 s. On the radiogram record the decline of the curve. The amplitude of this decrease corresponds to the amount of the radioactive tracer that passed from the bell to the lungs while inhaling (A). The patient then takes a deep breath and holds the breath again for 20 seconds. On the radiogram, the curve rises towards the zero line at this time. The amplitude of the recorder's pen movement during the breath hold after the expiration reflects the fraction of radioactivity of the first maximum breath of the air-xenon mixture, the output out of the lungs after maximum expiration (A) o The other fraction of radioactivity remaining in the lungs after expiration (A) is equal to

Compiled by S. Ryb

Nitsya between the amplitude of radioactivity that enters the lungs after the first maximum inhalation (A), and the amplitude of radioactivity, leaving the lungs after exhalation (A). In parallel, during the maximum inhalation and maximum expiration, the vital capacity of the lungs is recorded using a spirogram. The following results were obtained from the subject. The vital capacity of the lungs is 2,4l, A 6 cm, A 3 cm, A4 A - А 3 6 cm - 3 cm - 3 cm.

OOL ZHELh (A: Ar) 2.4 x (3: 3) 2.4 liters.

Claims (1)

Invention Formula A method of radioisotope measurement of residual lung volume, including radiography during a 10–20 second breathing delay after the maximum inhalation of the air-xenon mixture and the subsequent maximum expiration, measurement of the vital capacity of the lungs, followed by calculating the residual lung volume that, in order to reduce the research time, to simplify the method, the radioactive fractions of the lungs are measured after the maximum inhalation and exhalation and the fraction of radioactivity that comes out of the lungs after the maximum ydoha and residual lung volume is calculated by the formula OOL K --- ™ - ACH where OOL - residual lung volume} K is the vital capacity of the lungs; A - radioactivity fraction the first maximum inspiratory indicator remaining in the lungs after maximum expiration; A - radioactivity fraction the first maximum inhale of the indicator, coming out of the lungs after the maximum expiration. Editor N.Gorvat Tehred M. Didyk  Order 2822/42 Circulation 789 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 Proofreader A. Obruchar Subscription