The results of MRT and RCT researches of the brain and paranasal sinus in 20,359 patients received on X-ray tomograph “Somatom Plus 4” and MR-imager “Magnetom Vision Plus” (induction — 1,5 T) are analyzed. In 325 patients (1,59 %) at the age of from 9 to 65 years cysts of maxillary sinus are revealed. In 211 (64,9 %) there is marked a combination of the cyst of the sinus and one or another disease of the brain: a malignant tumour — 41, benign tumour — 31, arachnoidal cyst — 18, abscess of the brain, neuro AIDS — 1, malformation of the vessels — 17, diffuse atrophy — 22, ischemic stroke — 21, hemorrhagic stroke — 24, subarachnoid hemorrhage — 19, subdural haematoma — 17.
