3D-Double-Inversion Recovery detects perilesional gliosis better than 3D-FLAIR and postcontrast T1 imaging in calcified neurocysticercosis

Background: Perilesional gliosis is an important substrate for seizures in patients harboring a calcified neurocysticercosis (NCC) lesion and magnetic resonance imaging (MRI) is useful for evaluating gliosis. Aims: The purpose of this study was to evaluate the usefulness of double-inversion recovery (DIR) sequence for identifying perilesional gliosis. Settings and Design: Hospital-based cross-sectional study. Methods and Materials: Forty-five patients with seizures were included in this study and a total of 88 calcified lesions identified on susceptibility weighted imaging (SWI) were evaluated on 3D-fluid attenuating inversion recovery (FLAIR), 3D-DIR, and 3D-postcontrast T1-weighted imaging on a 3T MRI for the presence of perilesional signal changes/enhancement. Perilesional signal was rated on a semiquantitative scale from grade 0 to 2 by independent raters. Statistical Analysis Used: Friedman, Wilcoxon signed rank, and Kappa tests were used. Results: 3D-DIR sequence performed better than both 3D-FLAIR and postcontrast 3D-T1W sequences as more number of lesions showed perilesional signal change on DIR sequence. DIR sequence showed perilesional signal abnormality in 24 lesions in which 3D-FLAIR was normal, whereas in another 18 lesions, it demonstrated perilesional signal changes better than 3D-FLAIR. In only three lesions, FLAIR was found to be superior to DIR sequence, whereas postcontrast T1W images showed rim enhancement in five cases where no perilesional signal change was seen on FLAIR/DIR sequences. Conclusions: Combining 3D-DIR with 3D-FLAIR, and postcontrast 3D-T1W sequences is beneficial for evaluation of calcified NCC lesions and 3D-DIR sequence is better than other two sequences for perilesional signal abnormalities.