Improved ability of demonstrating ocular masses on 3.0 T MR scanner using PROPELLER: a multi-center study / 中华放射学杂志

ABSTRACT

Objective:To investigate the value of periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) in improving ability of demonstrating ocular masses on 3.0 T MR scanner.Methods:This study was a multi-center prospective study involving 6 centers. From July 2018 to January 2020, totally 413 patients with ocular masses from 6 centers were prospectively enrolled, and all of them underwent T 1WI and T 2WI, PROPELLER T 1 FLAIR and T 2WI, and contrast-enhanced scans. The signal intensity of eyelid, vitreous body, lacrimal gland, intraorbital segment of optic nerve, and orbital masses of eyelid, intraocular, lacrimal gland and retrobulbar were measured by two radiologists, and the signal to noise ratio (SNR) and contrast noise ratio (CNR) were calculated. The 5-point scoring method was used to evaluate the motion artefacts, tumor edges and the relationship between the tumor and adjacent structures, and the overall score of image quality was calculated. Paired t-test or Wilcoxon signed rank test was used to compare the image quality between PROPELLER and non-PROPELLER images. Results:The SNR and CNR of PROPELLER T 2WI were higher than those of non-PROPELLER T 2WI (all P<0.001). The SNR and CNR of PROPELLER T 1 FLAIR were lower than those of non-PROPELLER T 1WI (all P<0.05). The scores of artefacts and overall image quality in PROPELLER images were higher than those in non-PROPELLER images (all P<0.001). The tumor edge and the relationship between the tumor and adjacent structures scores of eyelid, intraocular, and lacrimal gland masses in PROPELLER images were higher than those in non-PROPELLER images (all P<0.001),while compared to non-PROPELLER images, retro-global masses in PROPELLER images showed no significant differences (all P>0.05). Conclusion:PROPELLER can reduce ocular motion artefacts, effectively improve image quality and ability of demonstrating anterior (eyelid, intraocular, and lacrimal gland) masses.