Enhancing Orbital MRI Quality: Optimization of Saturation Pads for 1.5T

Abstract

Objective: This study aimed to compare the effectiveness of different eye pads in enhancing magnetic field homogeneity using the Spectral Presaturation with Inversion Recovery (SPIR) technique. Materials and Methods: A prospective study was approved by the Ethics Committee and involved thirty patients undergoing orbital MRI with no current abnormalities. Patients were randomly assigned to one of three groups: uncooked jasmine rice, polystyrene ball bullet foam, or sugar cane syrup. Each patient underwent imaging twice - first without a pad and then with a pad on the eyelid. An experienced neuroradiologist, blinded to pad compositions, evaluated the images quantitatively and qualitatively. Statistical analyses included the Kruskal-Wallis rank test for signal-to-noise (SNR) and contrast-to-noise ratios (CNR), Dunn’s test for post-hoc comparisons, the Wilcoxon signed-rank test for qualitative pre- and post-pad differences, and Fisher’s exact test for group differences, with significance set at P < 0.05. Results: The uncooked jasmine rice group showed higher SNR and CNR, particularly in the medial rectus muscle (MRM). Significant improvements in the visual scale were noted for the optic nerve sheath complex (P = 0.002), MRM (P = 0.005), motion artifact (P = 0.034), and susceptibility artifact (P = 0.030) in both the uncooked jasmine rice and sugar cane syrup groups. Notably, none of the participants in the rice group exhibited a degraded visual scale for MRM or increased susceptibility artifact after pad placement. Conclusion: This study highlights the effectiveness of uncooked jasmine rice and sugar cane syrup as materials for enhancing orbital MRI quality, especially in earlier scanner models.

Keywords

• Fat suppression
• Orbit
• MRI
• Saturation pad
• SPIR