Diagnostic accuracy of semiautomatic lesion detection plus quantitative susceptibility mapping in the identification of new and enhancing multiple sclerosis lesions

Abstract

PurposeTo evaluate the diagnostic accuracy of a novel non-contrast brain MRI method based on semiautomatic lesion detection using T2w FLAIR subtraction image, the statistical detection of change (SDC) algorithm (T2w + SDC), and quantitative susceptibility mapping (QSM). This method identifies new lesions and discriminates between enhancing and nonenhancing lesions in multiple sclerosis (MS).MethodsThirty three MS patients who had MRIs at two different time points with at least one new Gd-enhancing lesion on the 2nd MRI were included in the study. For a reference standard, new lesions were identified by two neuroradiologists on T2w and post-Gd T1w images with the help of T2w + SDC. The diagnostic accuracy of the proposed method based on QSM and T2w + SDC lesion detection (T2w + SDC + QSM) for assessing lesion enhancement status was determined. Receiver operating characteristic (ROC) analysis was performed to compute the optimal lesion susceptibility cutoff value.ResultsA total of 165 new lesions (54 enhancing, 111 nonenhancing) were identified. The sensitivity and specificity of T2w + SDC + QSM in predicting lesion enhancement status were 90.7% and 85.6%, respectively. For lesions ≥50 mm3, ROC analysis showed an optimal QSM cutoff value of 13.5 ppb with a sensitivity of 88.4% and specificity of 88.6% (0.93, 95% CI, 0.87–0.99). For lesions ≥15 mm3, the optimal QSM cutoff was 15.4 ppb with a sensitivity of 77.9% and specificity of 94.0% (0.93, 95% CI, 0.89–0.97).ConclusionThe proposed T2w + SDC + QSM method is highly accurate for identifying and predicting the enhancement status of new MS lesions without the use of Gd injection.

Clinical Integration of Automated Processing for Brain Quantitative Susceptibility Mapping: Multi‐Site Reproducibility and Single‐Site Robustness

“…The arrow points to a lesion that is hyperintense on QSM but nonenhancing on the contrast enhanced T1‐weighted image. Recent efforts indicate that enhancement or lack thereof on QSM of lesions seen on T2 can predict T1 enhancement . Figure shows an intracranial hemorrhage.…”

Quantitative Susceptibility Mapping: Technical Considerations and Clinical Applications in Neuroimaging

“…Therefore, iron quantification will also help in predicting the severity of disability and cognitive impairment. 63,68,69 Various US Food and Drug Administration (FDA)-approved DMDs [Disease Modifying Drugs] have exhibited alterations in the microglial activation, and therefore the extent of iron accumulation in the microglia of chronic inflammatory lesions. These drugs can be used for monitoring the iron levels in MS lesions and their serial response to them.…”

“…These drugs can be used for monitoring the iron levels in MS lesions and their serial response to them. 63,68,69 Venous Oxygen Saturation Susceptibility maps and QSM have been recently used to measure the venous oxygen saturation and hence the cerebral metabolic rate of oxygen. Various studies have shown that the cerebral venous oxygen saturation is altered in neurological diseases.…”

“…The exact pathogenesis validating this correlation is that increased iron accumulation may promote damage through oxidative stress and lead to cellular degradation by blocking the repair mechanisms and activating the microglia. Therefore, iron quantification will also help in predicting the severity of disability and cognitive impairment 63,68,69 . Various US Food and Drug Administration (FDA)‐approved DMDs [Disease Modifying Drugs] have exhibited alterations in the microglial activation, and therefore the extent of iron accumulation in the microglia of chronic inflammatory lesions.…”

Estimation of Multiple Sclerosis lesion age on magnetic resonance imaging

“…A novel feature of our algorithm is the use of QSM in addition to the radiomic features of T1w without and with gadolinium contrast (T1w+c), T2-weighted (T2w), and fluid attenuated inversion recovery (FLAIR) images, as well as demographic information. QSM ( de Rochefort et al, 2010 ; Wang and Liu, 2014 ; Wang et al, 2017 ) is a promising MRI technique for mapping tissue susceptibility changes related to myelin breakdown and iron deposition in MS lesions ( Langkammer et al, 2013 ; Stüber et al, 2016 ; Wisnieff et al, 2015 ; Deh et al, 2018 ) and has recently been shown to predict lesion enhancement status with high diagnostic accuracy without using gadolinium ( Zhang et al, 2016b , 2018 ). Previous cross-sectional and longitudinal studies have also observed that the QSM signal increases rapidly as a new lesion transitions from enhancing to non-enhancing phase, reaching a peak value approximately two years after lesion formation and then slowly decaying away in the final stages of a glial scar ( Zhang et al, 2019b ; Chen et al, 2014 ).…”