Interthalamic adhesion alterations in multiple sclerosis: associations with thalamic damage and cognition

Arthur Fournet, Fanny Munsch, Ismail Koubiyr, Julie P. Vidal, Sergio Morell-Ortega, Aurore Saubusse, Julie Charré-Morin, Katy K. Lataste, Audrey Lavielle, Zhang Bei, Pierrick Coupé, Emmanuel J. Barbeau, Vinod J. Kumar, Michael Hornberger, Vincent Dousset, Bruno Brochet, José V. Manjón, Aurélie Ruet, Thomas Tourdias
Journal of Neurology. 2026-08-20; 273(9):
DOI: 10.1007/s00415-026-14069-5

1. J Neurol. 2026 Aug 20;273(9):535. doi: 10.1007/s00415-026-14069-5.

Interthalamic adhesion alterations in multiple sclerosis: associations with
thalamic damage and cognition.

Fournet A(1), Munsch F(2), Koubiyr I(3), Vidal JP(4), Morell-Ortega S(5),
Saubusse A(6), Charré-Morin J(6), Lataste KK(6), Lavielle A(1)(2), Bei Z(7),
Coupé P(8), Barbeau EJ(9), Kumar VJ(10), Hornberger M(11), Dousset V(1)(2)(12),
Brochet B(12), Manjón JV(5), Ruet A(6)(12), Tourdias T(13)(14)(15).

Author information:
(1)Neuroimagerie Diagnostique et Thérapeutique, CHU de Bordeaux, 33000,
Bordeaux, France.
(2)Institut de Bio-Imagerie IBIO, Univ. Bordeaux, 33000, Bordeaux, France.
(3)MS Center Amsterdam, Anatomy and Neurosciences, Amsterdam Neuroscience,
Amsterdam UMC Location VUmc, Amsterdam, The Netherlands.
(4)CNRS UMR1214, ToNIC, Université de Toulouse, 31000, Toulouse, France.
(5)Instituto de Aplicaciones de las Tecnologías de la Información y de las
Comunicaciones Avanzadas (ITACA), Universitat Politècnica de València, Valencia,
Spain.
(6)Service de Neurologie, CRC SEP, CHU de Bordeaux, 33000, Bordeaux, France.
(7)Canon Medical Systems Europe, Amstelveen, The Netherlands.
(8)CNRS, LABRI, UMR5800, PICTURA, Univ. Bordeaux, Bordeaux INP, 33400, Talence,
France.
(9)CNRS UMR5549, Centre de Recherche Cerveau et Cognition (Cerco), Université de
Toulouse, 31000, Toulouse, France.
(10)Max Planck Institute for Biological Cybernetics, Tuebingen, Germany.
(11)Clinical Neuroscience, Clinical and Experimental Sciences, Faculty of
Medicine, University of Southampton, Southampton, UK.
(12)INSERM U1215, Neurocentre Magendie, Univ. Bordeaux, 3300, Bordeaux, France.
(13)Neuroimagerie Diagnostique et Thérapeutique, CHU de Bordeaux, 33000,
Bordeaux, France. .
(14)Institut de Bio-Imagerie IBIO, Univ. Bordeaux, 33000, Bordeaux, France.
.
(15)INSERM U1215, Neurocentre Magendie, Univ. Bordeaux, 3300, Bordeaux, France.
.

BACKGROUND/OBJECTIVES: We investigated whether the interthalamic adhesion (IA),
a midline structure connecting the thalami, is altered in multiple sclerosis
(MS) and associated with thalamic damages and cognition.
METHODS: We prospectively included 32 clinically isolated syndrome/early MS, 31
relapsing-remitting MS, 31 primary-progressive MS patients, and 103 matched
controls. All underwent anatomical 3 T MRI and completed a comprehensive
cognitive battery. IA presence, subtype, and volume were assessed by two blinded
readers. Thalamic nuclei and other brain structures were segmented
automatically. We compared IA subtypes/volumes across groups, analyzed their
predictors, and explored cognitive associations with multivariate regressions. A
deep-learning-based IA segmentation tool was also developed and externally
validated on 30 new patients.
RESULTS: IA prevalence did not differ between MS and controls (81.9% vs 74.7%).
MS patients showed a shift toward a short IA subtype and reduced IA volume (mean
[SD], 146.8 [117.9] vs 230.2 [138.2] mm3; p