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Motivation to undertake research on brain surface temperature in clinical practice is based on a strong
conviction that the enormous progress in thermal imaging techniques and camera design has a great application
potential. Intraoperative imaging of pathological changes and functionally important areas of the brain is not yet
fully resolved in neurosurgery and remains a challenge. A study of temperature changes across cerebral
cortex was performed for five patients with brain tumors (previously diagnosed using magnetic resonance or
computed tomography) during surgical resection or biopsy of tumors. Taking into account their origin and
histology the tumors can be divided into the following types: gliomas, with different degrees of malignancy (G2
to G4), with different metabolic activity and various temperatures depending on the malignancy level (3
patients), hypervascular tumor associated with meninges (meningioma), metastatic tumor - lung cancer with a
large cyst and noticeable edema. In the case of metastatic tumor with large edema and a liquid-filled space
different temperature of a cerebral cortex were recorded depending on metabolic activity. Measurements have
shown that the temperature on the surface of the cyst was on average 2.6 K below the temperature of
surrounding areas. It has been also observed that during devascularization of a tumor, i.e. cutting off its blood
vessels, the tumor temperature lowers significantly in spite of using bipolar coagulation, which causes additional
heat emission in the tissue. The results of the measurements taken intra-operatively confirm the capability of a
thermal camera to perform noninvasive temperature monitoring of a cerebral cortex. As expected surface
temperature of tumors is different from surface temperature of tissues free from pathological changes. The
magnitude of this difference depends on histology and the origin of the tumor. These conclusions lead to taking
on further experimental research, implementation and further verification of the thermal imaging method and its
usefulness in clinical practice. In particular the research will be undertaken on intraoperative temperature
changes of active cerebral cortex areas in post-anesthetic recovery.
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