ADVANCED MAGNETIC RESONANCE IMAGING TECHNIQUE IN THE DIAGNOSIS OF OVARIAN LESIONS

The aim objective: to improve the methods, protocol specification and assessment of the possibilities of the complex magnetic resonance imaging in the diagnosis of ovarian lesions. Materials and methods. From 2011 to 2015 256 patients with 289 ovarian lesions underwent pelvic and abdominal (if necessary) MRI results compared with histological data, obtained intraoperatively, or verification is made on the basis of dynamic observation for at least 6 months. Results. Quantitative estimation showed that the amplitude of the accumulation of the contrast agent was significantly higher in malignant tumors – 167% (115.2-212.5%), than benign – 61.2% (41.2-99.0%; P<0.001) and borderline tumors – 85.7% (58.3-138,2%; P<0.01); the period of 1/2 signal intensity rise significantly higher in benign tumors of 35.1 seconds (30.8 seconds and 42.5 seconds) than in the borderline – 27.9 sec (23.5 sec to 29.8 sec; P<0.05), and malignant – 23,1 sec (20.5 h is 30.9 sec; P=0.01). Maximum slope of the contrast enhancement curve (%/sec) amounted to 1.78 (1.0-2.6); 2.86 (2.01-3.95) and 6.1 (4.19-9.46) for benign, borderline and malignant tumors, respectively, and was significantly higher in malignant invasive tumors (P<0.01). The average values of the аpparent diffusion coefficient (ADC) of malignant tumors was significantly lower than the corresponding values in benign (1.012±0.18 mm2 /s×10-3 and 1.54±0.25 mm2 /s×10-3, respectively), the value intervals do not overlap. The threshold value of ADC for malignant ovarian tumors: less 1,139 mm2 /s×10-3. Advanced MRI technique accuracy was 92.1%, with sensitivity of 93.6% and specificity of 91.2%. Conclusions. Optimization of the technique and protocol standardization of complex MR studies in patients with ovarian lesions provides a complete diagnostic information about the nature, allows if necessary to adequately assess the spread of malignant tumors in primary staging.