RU2012880C1 - Method of determination degree of brain tissue edema - Google Patents

Abstract

FIELD: medicine. SUBSTANCE: brain tissue is frozen in liquid nitrogen, sections of white and grey substances having thickness 200 μm being prepared. Then optical transmission at wavelength 400 nm is measured. If optical transmission is 1.9-6.8% and 4.4-14.2% for white and for grey substances respectively then slight degree of brain tissue edema takes place. If optical transmission is 6.9-10.9% and 14.3-18.4% for white and for grey substances respectively then medium degree of edema takes place. Distinct degree of edema is diagnosed if optical transmission is 11.0- 14.2% and 18.5-24.6% for white and for grey substances respectively. EFFECT: increases accuracy of the method.

Description

 The invention relates to medicine, namely to neurosurgery, pathological anatomy and forensic medical examination, and can be used to quantify the severity of edema of brain tissue, for expert assessment of the severity of spinal cord and brain injuries.

 A known histological method for assessing tissue swelling of the brain and spinal cord, based on the collection of brain tissue, wiring, staining it with hematoxylin-eosin and the van Gieson method and the subsequent study of micropreparations through microscopy / G. Merkulov, Pathology and anatomical technique. Medicine, 1969, p. 164-171 /.

 On micropreparations with cerebral edema, swelling and varicosity of the myelin sheaths, swelling and plasmatodendrosis of astrocytes, unstable swelling of oligodendrocytes are found. Veins and capillaries are full-blooded. Swelling, chromatolysis, melting of ganglion cells and ischemia-related secondary changes in the form of pycnosis are common.

 A significant drawback of this method is that it is a very time-consuming method that requires a lot of time / at least a week /. In addition, in this method there are no quantitative criteria and in many respects it depends on the qualification of the pathologist or forensic expert, i.e. there is an element of subjectivity. Express diagnostics, for example, during surgery on the brain in order to show the degree of swelling of the brain tissue in the area of surgical intervention, based on this method, is not possible.

 Closest / prototype / to the claimed is a method for determining water in the cerebral cortex in patients with severe traumatic brain injury / Gaykova O.N., Ismail T.M., Diagnostics and complex treatment of closed traumatic brain injury, 1982, p. 110-113 /.

In order to diagnose cerebral edema in the area of the contusion area during the operation, 100 mg pieces of the cerebral cortex were taken. Then these pieces were dried at 105 ^about With to constant weight. Calculation of water was carried out as a percentage of wet non-fat weight of the bark.

 A significant drawback of this method is the long study time - several hours (the time required to slowly dry pieces of the brain), as well as the greater likelihood of a method error due to the fact that part of the brain tissue sticks, smearing, for example, on paper, on the scales and is lost in the process of research. Among other things, the method is very painstaking and rather complicated in the study and cannot be used for express diagnostics.

 The purpose of the invention: improving accuracy, rapid diagnosis of the degree of edema of the brain tissue.

 This goal is achieved by freezing the brain tissue in liquid nitrogen, preparing slices of white or gray matter 200 microns thick and measuring optical transmittance at a fixed wavelength (400 nm), with 1.9-6.8% transmittance of white matter, gray 4 4-14.2 diagnose a mild degree of cerebral edema; with 6.9-10.9% transmittance of white matter, and gray 14.3-18.4% - moderate edema; at 11.0-14.2% transmittance of the white matter of the brain, and gray 18.5-24.6%, a pronounced degree of cerebral edema is diagnosed.

 The method is as follows: during surgery on the brain or spinal cord, or during pathological anatomical autopsy, small pieces of gray or white brain matter are taken in size of 1 x 1 x 1 mm. They are placed in liquid nitrogen for 1-2 s, and then one slice 200 microns thick is prepared from them on a microtome. The slice is placed between two fat-free glass slides and placed in an SF-18 spectrophotometer, where its optical properties / percent transmission of a given wavelength / are determined at a fixed wavelength of 400 nm. With a percentage of transmission of white matter 1.9-6.8, gray 4.4-14.2, a mild degree of swelling of the brain tissue is diagnosed; with a percentage of transmission of white matter of 6.9-10.9, and gray 14.3-18.4 there is an average degree of edema; with a percentage of transmission of white matter of the brain 11.0-14.2, and gray 18.5-24.6, pronounced swelling of the brain tissue is diagnosed. Normal values for the white matter of the brain at a wavelength of 400 nm are 3.0 ± 1.11 percent transmittance, for gray 6.6 ± 0.27 percent transmittance.

 PRI me R. Patient B. was in the clinic of neurosurgery of the Novosibirsk Scientific Research Institute of Nuclear Medicine for a brain tumor in the left frontoparietal-temporal region. Operated: decompressive trepanation of the skull in the left frontotoparietal-temporal region, biopsy of a deep tumor (glioblastoma), and dura mater were performed. After three days, the patient dies from a hemorrhage in the tumor, non-stopping brain edema.

 A pathological and anatomical autopsy revealed a malignant intracerebral tumor in the left fronto-parietal-temporal region. Marked swelling of the brain tissue. In order to diagnose the degree of cerebral edema in its various zones, three pieces of gray matter of the brain were taken: one - directly next to the tumor (subcortical formations - thalamus), the second - the cortex of the pole of the left frontal lobe, the third - the cortex of the pole of the frontal lobe. The size of the pieces is 1 x 1 x 1 mm. Pieces here are dipped in liquid nitrogen for 1-2 s. Of these, one slice 200 microns thick was prepared on a microtome. Slices were placed between two fat-free glass slides and placed in an SF-18 spectrophotometer. At a wavelength of 400 nm, their optical properties were determined: 21.5% transmission was obtained in the first slice, 17.0% in the second, and 17% in the third.

 Thus, on the basis of this simple method, carried out for 5 min, the following conclusion is given with a high degree of accuracy: there is a pronounced cerebral edema in the tumor area, moderate edema in the pole of the left frontal lobe, and also in the opposite hemisphere of the brain moderate swelling of the brain tissue.

Claims (1)

 METHOD FOR DETERMINING THE DEGREE OF THE Edema of the brain tissue by examining it, characterized in that the brain tissue is frozen in liquid nitrogen, slices of white and gray matter are prepared with a thickness of 200 μm, the optical transmittance is measured at a fixed wavelength of 400 nm, the percentage of transmittance is calculated and at a value of for white matter 1.9 - 6.8%, for gray - 4.4 - 14.2% determine a mild degree of edema, with a value for white - 6.9 - 10.9%, for gray - 14.3 - 18 , 4% - the average degree of edema, and with a value for white - 11.0 - 14.2%, for gray - 18.5 - 24.6% - expressed th.