Contributions
Abstract: EP1515
Type: ePoster
Abstract Category: Pathology and pathogenesis of MS - 21 Imaging
Background: B-cell lymphoid aggregates have been implicated in meningeal inflammation, microglial activation, cortical grey matter demyelination, and disability progression in multiple sclerosis (MS) (1). Gadolinium-enhanced 3D-FLAIR (Gd-3D-FLAIR) MRI has recently been shown to identify foci of leptomeningeal enhancement (LME) in MS (2), thought to be an imaging biomarker for leptomeningeal inflammation. In order to determine disease modifying therapy (DMT) efficacy in controlling LME, it will be necessary to control for timing of image acquisition following gadolinium administration.
Goals: To identify the optimal timing of Gd-3D-FLAIR acquisition following gadolinium administration to identify LME in MS.
Methods: 8 foci of LME in 3 different MS patients were imaged by Gd-3D-FLAIR at 4 successive time points following injection spanning 4-45 minutes. Enhancement intensity was quantified by region-of-interest (ROI) measurements, averaged in sagittal and axial planes, with generation of time-intensity curves.
Results: Lesions were heterogeneous without definable optimal time for image acquisition. Mean time to peak enhancement = 23.8 min (standard deviation = 15 min, range 2-42 min). Rough guidelines for optimal timing of image acquisition suggest 10-25 min as reasonable parameters. Additionally, enhancement curves exhibited 3 different variations, remarkably similar to those described by Tofts (3): 3 lesions revealed prolonged wash-in curve; 2 lesions revealed slow wash-in/slow wash-out; and 3 lesions revealed rapid wash-in/rapid wash-out.
Conclusions:
1) While 10-25' post-injection acquisition seems appropriate, accurate assessment of DMT efficacy in modulating LME will require rigorous controlling of timing of image acquisition following gadolinium administration.
2) LMEs in MS are heterogeneous revealing 3 different types of wash-in/wash-out curves, suggesting a new avenue for investigation of DMT modulation of LME.
References:
1. Howell OW, Reeves CA, Nicholas R, et al. Meningeal inflammation is widespread and linked to cortical pathology in multiple sclerosis. Brain 2011; 134:2755-2771.
2. Absinta M, Vuolo L, Rao A, et al. Gadolinium-based MRI characterization of leptomeningeal inflammation in multiple sclerosis. Neurology 2015; 85:18-28.
3. Tofts PS. Modeling tracer kinetics in dynamic Gd-DTPA MR imaging. JMRI 1997; 7:91-101.
Disclosure:
David S. Titelbaum, M.D.: nothing relevant to disclose
Renate Engisch, M.D.: nothing relevant to disclose
Eric D. Schwartz, M.D.: nothing relevant to disclose
Salvatore Q. Napoli, M.D.: nothing relevant to disclose
Jacob Sloane, M.D.: nothing relevant to disclose
Abstract: EP1515
Type: ePoster
Abstract Category: Pathology and pathogenesis of MS - 21 Imaging
Background: B-cell lymphoid aggregates have been implicated in meningeal inflammation, microglial activation, cortical grey matter demyelination, and disability progression in multiple sclerosis (MS) (1). Gadolinium-enhanced 3D-FLAIR (Gd-3D-FLAIR) MRI has recently been shown to identify foci of leptomeningeal enhancement (LME) in MS (2), thought to be an imaging biomarker for leptomeningeal inflammation. In order to determine disease modifying therapy (DMT) efficacy in controlling LME, it will be necessary to control for timing of image acquisition following gadolinium administration.
Goals: To identify the optimal timing of Gd-3D-FLAIR acquisition following gadolinium administration to identify LME in MS.
Methods: 8 foci of LME in 3 different MS patients were imaged by Gd-3D-FLAIR at 4 successive time points following injection spanning 4-45 minutes. Enhancement intensity was quantified by region-of-interest (ROI) measurements, averaged in sagittal and axial planes, with generation of time-intensity curves.
Results: Lesions were heterogeneous without definable optimal time for image acquisition. Mean time to peak enhancement = 23.8 min (standard deviation = 15 min, range 2-42 min). Rough guidelines for optimal timing of image acquisition suggest 10-25 min as reasonable parameters. Additionally, enhancement curves exhibited 3 different variations, remarkably similar to those described by Tofts (3): 3 lesions revealed prolonged wash-in curve; 2 lesions revealed slow wash-in/slow wash-out; and 3 lesions revealed rapid wash-in/rapid wash-out.
Conclusions:
1) While 10-25' post-injection acquisition seems appropriate, accurate assessment of DMT efficacy in modulating LME will require rigorous controlling of timing of image acquisition following gadolinium administration.
2) LMEs in MS are heterogeneous revealing 3 different types of wash-in/wash-out curves, suggesting a new avenue for investigation of DMT modulation of LME.
References:
1. Howell OW, Reeves CA, Nicholas R, et al. Meningeal inflammation is widespread and linked to cortical pathology in multiple sclerosis. Brain 2011; 134:2755-2771.
2. Absinta M, Vuolo L, Rao A, et al. Gadolinium-based MRI characterization of leptomeningeal inflammation in multiple sclerosis. Neurology 2015; 85:18-28.
3. Tofts PS. Modeling tracer kinetics in dynamic Gd-DTPA MR imaging. JMRI 1997; 7:91-101.
Disclosure:
David S. Titelbaum, M.D.: nothing relevant to disclose
Renate Engisch, M.D.: nothing relevant to disclose
Eric D. Schwartz, M.D.: nothing relevant to disclose
Salvatore Q. Napoli, M.D.: nothing relevant to disclose
Jacob Sloane, M.D.: nothing relevant to disclose