Intracortical lesions by 3T magnetic resonance imaging and correlation with cognitive impairment in multiple sclerosis

Abstract

Background Accurate classification of MS lesions in the brain cortex may be important in understanding their impact on cognitive impairment. Improved accuracy in identification/classification of cortical lesions was demonstrated in a study combining two MRI sequences: double inversion recovery (DIR) and T1-weighted phase-sensitive inversion recovery (PSIR). Objective To evaluate the role of intracortical lesions (IC) in MS related cognitive impairment (CI) and compare it to the role of mixed (MX), juxtacortical (JX), the sum of IC + MX and with total lesions as detected on DIR/PSIR images. Correlations between CI and brain atrophy, disease severity and disease duration were also sought. Methods 39 patients underwent extensive neuropsychological testing and were classified into: normal and impaired. Images were obtained on a 3T scanner and cortical lesions were assessed blind to the cognitive status of the subjects. Results 238 cortical lesions were identified (130 IC, 108 MX) in 82% of the patients, 39 JX lesions were also identified. Correlations between CI and MX lesions alone (p=0.010) and with the sum of IC + MX lesions (p=0.030) were found. A correlation between severity of CI and EDSS was also seen (p=0.009). Conclusion Cortical lesions play an important role in CI. However our results suggest that lesions that remain contained within the cortical ribbon do not play a more important role than ones extending into the adjacent white matter; furthermore the size of the cortical lesion, and not the tissue specific location, may better explain their correlation with CI.

Improved Visualization of Cortical Lesions in Multiple Sclerosis Using 7T MP2RAGE

“…Previous work correlating different types and severity of MS with cortical lesion number has been, for the most part, performed at low field strength using double and phase-sensitive inversion recovery [34][35][36][37][38] ; it is likely that cortical lesions identified in those studies were heavily skewed toward juxtacortical and leukocortical lesions, underestimating the number of intracortical lesions. 39 With the increased sensitivity to small cortical lesions provided by MP2RAGE, we were able to more accurately determine the correlation between cortical and white matter lesions.…”

MAGNIMS consensus guidelines on the use of MRI in multiple sclerosis—clinical implementation in the diagnostic process

“…DIR improves the sensitivity of MRI to detect cortical lesions in vivo, [62][63][64][65] although it has shown low interobserver concordance, particularly for the detection of pure intracortical lesions, thereby limiting its value in clinical practice. 63 Other sequences, such as phase-sensitive inversion recovery (PSIR) and highresolution 3D magnetization-prepared rapid acquisition with gradient echo (MPRAGE), improve intracortical lesion classification, 62,63,[67][68][69] especially at high magnetic field strengths.…”

MAGNIMS consensus guidelines on the use of MRI in multiple sclerosis—establishing disease prognosis and monitoring patients

“…[121][122][123][124][125][126] Several MRI techniques, including double inversion recovery and phase sensitive inversion recovery, have been used to detect, score and interpret cortical grey matter lesions, but these applica tions lack standardization. [127][128][129] Advanced, quanti tative imaging techniques may also acquire a central role for evaluating the course of MS pathology in the near future.…”