Application of magnetic resonance 3D-SPACE sequence combined image fusion technique in preoperative evaluation of pituitary macroadenoma.

Abstract

To evaluate the image quality of magnetic resonance 3D-sampling perfection with application-optimized contrasts by using different filp angle evolutions (3D-SPACE) sequence combined with different fusion methods in image fusion technology and the application value of fusion technology in preoperative evaluation of pituitary macroadenoma. We collected MRI data of 43 patients with pituitary macroadenoma confirmed by Xiangya Hospital of Central South University, including collecting conventional MRI scan+enhancement, 3D-SPACE T2WI, and 3D-SPACE T1WI+C image data. 3D-SPACE sequence fusion was used in 6 combinations of 3D-SPACE T2WI/3D-SPACE T1WI+C, which were normal phase+normal phase, reverse phase+normal phase, normal phase+reverse phase, reverse phase+reverse phase, and normal phase pseudo color+normal phase, normal phase+normal phase pseudo color. Two senior radiologists used semi-quantitative methods to evaluate and compare the image quality of different combinations to obtain the best fusion mode. According to the degree of tumor invasion of the optic chiasma, oculomotor nerve, and cavernous sinus vessels, the MRI enhancement, 3D-SPACE T2WI, 3D-SPACE T1WI+C, and 2 3D-SPACE sequence fusion images were performed according to a three-level score system. Taking the intraoperative observation as the gold standard, Fisher probability exact method was used to compare different sequences to show the difference between the degree of invasion of the pituitary macroadenoma to the surrounding tissue and the intraoperative results. The Kruskal-Wallis H rank sum test showed that among the 6 image fusion modes, 3D-SPACE T1WI+C normal phase pseudo-color and 3D-SPACE T2WI normal phase fusion images had the best quality (P<0.05). No significance was observed among the 4 groups in the evaluation of consistency between the intraoperative findings and the graphically displayed extent of tumor invasion into oculomotor nerve (both level I, II, and III, P>0.05). The 3D-SPACE T2WI/3D-SPACE T1WI+C fusion images and the 3D-SPACE T2WI images showed better performance in the evaluation of consistency between the intraoperative findings and the graphically displayed extent of tumor invasion into optic chiasma (level II and III) than that in other two kinds of imaging data of the MRI enhancement group and 3D-SPACE T1WI+C group (P<0.01, P<0.05, respectively), with no significance being observed in level I. The 3D-SPACE T2WI/3D-SPACE T1WI+C fusion images and the 3D-SPACE T1WI+C images showed better performance in the evaluation of consistency between the intraoperative findings and the graphically displayed extent of tumor invasion into cavernous sinus vessels (level II) than that in other two kinds of imaging data of the MRI enhancement group and 3D-SPACE T2WI group (P<0.01, P<0.05, respectively), with no significance being observed in level I and III. Magnetic resonance 3D-SPACE sequence combined with image fusion technology is better than conventional magnetic resonance sequence for showing pituitary macroadenoma invasion of skull base vascular nerves. The invasion is better than the 3D-SPACE sequence alone, showing that the relationship between tumor and cavernous sinus vascular grade II better than the 3D-SPACE sequence alone. It has good application prospects for preoperative risk assessment and surgical plan.