Zafer Keser1, Arash Kamali2, Kyan Younes1, Paul E Schulz1, Flavia M Nelson3, Khader M Hasan2. 1. Department of Neurology, The University of Texas Health Science Center McGovern Medical School, Houston, TX. 2. Department of Interventional and Diagnostic Radiology, The University of Texas Health Science Center, McGovern Medical School, Houston, TX. 3. Department of Neurology, University of Minnesota, Minneapolis, MN.
Abstract
BACKGROUND AND PURPOSE: In 1948, Paul Yakovlev described an additional limbic circuit located basolateral to James Papez's circuit (1937) and included orbitofrontal cortex, amygdala, and dorsomedial nucleus of thalamus. This circuit is shown to be an important component of subcortical cognitive abilities. We aimed to demonstrate this circuit in a multiple sclerosis (MS) cohort using diffusion tensor imaging (DTI) and evaluate its role in MS-related cognitive impairment (CI). METHODS: We enrolled cognitively intact (n = 10) and impaired (n = 36) MS patients who underwent a comprehensive cognitive assessment; the minimal assessment of cognitive function in MS (MACFIMS) and structural magnetic resonance imaging. Correlation analyses between volumetric and DTI-derived values of the orbitofrontothalamic (OFT), amygdalothalamic tracts (ATTs), and dorsomedial nucleus of thalamus and CI index derived from MACFIMS were computed after adjustment for age, education, and lesion load. RESULTS: We observed a consistent trend between CI index and bilateral dorsomedial nucleus' mean diffusivity (MD) (r = .316; P = .02), left OFT Fractional anisotropy (FA) (r = -.302; P = .02), MD (r = .380; .006), and radial diffusivities (RDs) (r = .432; P = .002), also with right ATT FA (r = -.475; P = .0006) and left ATT FA ( = -.487; P = .0005). After Bonferroni correction, correlations of left OFT RD and right and left ATT FA with CI were found to be significant. CONCLUSIONS: Our study provides in vivo DTI delineation of Yakovlev's historical basolateral limbic circuit and establishes a role in MS-related CI. These findings may potentially pave the way for future clinical studies using targeted invasive and noninvasive neurostimulation modalities for CI in MS.
BACKGROUND AND PURPOSE: In 1948, Paul Yakovlev described an additional limbic circuit located basolateral to James Papez's circuit (1937) and included orbitofrontal cortex, amygdala, and dorsomedial nucleus of thalamus. This circuit is shown to be an important component of subcortical cognitive abilities. We aimed to demonstrate this circuit in a multiple sclerosis (MS) cohort using diffusion tensor imaging (DTI) and evaluate its role in MS-related cognitive impairment (CI). METHODS: We enrolled cognitively intact (n = 10) and impaired (n = 36) MSpatients who underwent a comprehensive cognitive assessment; the minimal assessment of cognitive function in MS (MACFIMS) and structural magnetic resonance imaging. Correlation analyses between volumetric and DTI-derived values of the orbitofrontothalamic (OFT), amygdalothalamic tracts (ATTs), and dorsomedial nucleus of thalamus and CI index derived from MACFIMS were computed after adjustment for age, education, and lesion load. RESULTS: We observed a consistent trend between CI index and bilateral dorsomedial nucleus' mean diffusivity (MD) (r = .316; P = .02), left OFT Fractional anisotropy (FA) (r = -.302; P = .02), MD (r = .380; .006), and radial diffusivities (RDs) (r = .432; P = .002), also with right ATT FA (r = -.475; P = .0006) and left ATT FA ( = -.487; P = .0005). After Bonferroni correction, correlations of left OFT RD and right and left ATT FA with CI were found to be significant. CONCLUSIONS: Our study provides in vivo DTI delineation of Yakovlev's historical basolateral limbic circuit and establishes a role in MS-related CI. These findings may potentially pave the way for future clinical studies using targeted invasive and noninvasive neurostimulation modalities for CI in MS.
Authors: Khader M Hasan; Indika S Walimuni; Humaira Abid; Richard E Frye; Linda Ewing-Cobbs; Jerry S Wolinsky; Ponnada A Narayana Journal: J Neurosci Date: 2011-11-16 Impact factor: 6.167
Authors: M K Houtchens; R H B Benedict; R Killiany; J Sharma; Z Jaisani; B Singh; B Weinstock-Guttman; C R G Guttmann; R Bakshi Journal: Neurology Date: 2007-09-18 Impact factor: 9.910
Authors: Zafer Keser; Khader M Hasan; Benson Mwangi; Refaat E Gabr; Joel L Steinberg; Jeffrey Wilken; Jerry S Wolinsky; Flavia M Nelson Journal: J Neuroimaging Date: 2016-08-19 Impact factor: 2.486
Authors: Zafer Keser; Khader M Hasan; Benson Mwangi; Kyan Younes; Mahsa Khayat-Khoei; Arash Kamali; John A Lincoln; Flavia M Nelson Journal: Front Neurol Date: 2018-03-12 Impact factor: 4.003