MRI-signs of structural and perfusion changes in chronic cerebral ischemia in liquidators of the aftermath of the Chernobyl nuclear power plant accident in the remote period

Cerebrovascular disease (CVD) was detected in 87% of the examined liquidators of accidents at the Chernobyl Nuclear Power Plant 7–8 years after participating in emergency recovery work with a radiation dose of ≤0.3 Gy. Analysis of the conducted studies shows that the results of structural methods of radiation diagnostics do not always correlate with the severity of the clinical picture. The use of an extended MRI examination of the brain to assess the correlation of anatomical and functional indicators of various observation groups in people with chronic cerebrovascular insufficiency seems promising.

Purpose. To compare structural MRI data of the brain and indicators of cerebral hemodynamic perfusion in LPA and patients in the control group.

Materials and methods: 147 patients aged from 55 to 87 years old with a diagnosis of chronic cerebrovascular disease were examined. The main group – 93 patients, the comparison group – 54 patients who were not exposed to radiation. The identified changes were assessed by the degree of atrophy of white and gray matter, by the degree of gliosis changes, and were compared with the data of perfusion parameters.

Results. Signs of the atrophic process of the brain were detected in 93.9% of the main group and in 76.7% of patients from the comparison group, microangiopathy – in 100.0 and 83.4%. The risk of developing atrophy and microangiopathy in LPA is 1.24 (p = 0.041) and 1.14 (p = 0.008), respectively. When comparing MRI perfusion parameters (CBV, CBF and MTT) between the cortex and glia in patients of the main and control groups, it was found that the cortex/glia ratio between CBV and CBF in the OG is lower than in the GS by 13.9 and 24.2, respectively %. A comparative analysis of MRI perfusion parameters showed that in LPA the ratio between CBV in the glia and cortex of the right hemisphere is lower, by 0.3 and 11.7%, and in the left hemisphere – by 19.3 and 22.9%. CBF in the glia of the right hemisphere of the LPA is increased by 6.9%, and in the cortex it is decreased by 14.2%, in the left hemisphere – by respectively 9.8 and 13.4%.

Conclusions. The study showed the high efficiency of contrast MRI perfusion and made it possible to identify the correlation of structural and perfusion changes in different research groups.

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