Dados do Trabalho

Título

ULTRA-HIGH-FIELD BRAIN IMAGING AT 7 TESLA MAGNETIC RESONANCE IN LAMA2-RD PATIENTS

Introdução

LAMA2-related muscular dystrophy (LAMA2-RD) is an autosomal recessive disorder that causes muscle weakness in a broad spectrum of phenotypic severity.. The disease affects muscle strength and causes brain abnormalities, such as high signal intensity in the white matter on T2 and FLAIR, and in rarer cases, cortical malformations. The correlation between motor severity and CNS abnormalities is not well understood, and few studies have detailed the brain MRI alterations in these patients. Ultra-high-field MRI [≥7 Tesla (7T)] has improved the capability to depict and characterize brain structures efficiently, with better signal-to-noise ratio and spatial resolution.

Objetivo

To compare the brain imaging findings at 7T magnetic resonance with the images obtained with 3 Tesla magnetic resonance techniques in patients with LAMA2-RD.

Método

Patients with LAMA2-RD who had previously 3T brain MRI were selected, and were submitted to a 7T brain MRI protocol. The patients included both the congenital muscular dystrophy (CMD) form of the disease (unable to walk) and the limb-girdle muscular dystrophy form (LGMD). Patients under 16 years old who could not tolerate the exam without anesthesia were excluded, as well as those who had previously undergone spine surgery.

Resultados

Four patients were submitted to the 7T brain MRI by now, aged between 26 and 40 years. Two patients had the phenotype of CMD, and two had LGMD. Three patients had epilepsy. The images revealed generalized white matter alterations with both field strengths, although the 7T better depicted a tigroid pattern, that could represent some perivascular preserved fibers. The subcortical area was preserved in certain regions among patients with the LGMD phenotype. All three patients with epilepsy showed cortical malformations, specifically polymicrogyria / cobblestone lissencephaly. These malformations were predominantly located in the occipital region and were not widespread across the cortex. Although the 7T MRI provided better resolution, it did not reveal additional cortical malformations compared to the 3T MRI. Also, due to 7T technical limitations, the occipital cortex was of limited identification, mainly in patient with accentuated kyphosis

Conclusão

Both patients with CMD and LGMD related to the LAMA2 gene exhibit CNS abnormalities. The 7T MRI provides better resolution, but did not identify more cortical malformations than previously identified with 3T.

Referências

Arreguin AJ, Colognato H. Brain Dysfunction in LAMA2-Related Congenital Muscular Dystrophy: Lessons From Human Case Reports and Mouse Models. Front Mol Neurosci. 2020 Jul 23;13:118. doi: 10.3389/fnmol.2020.00118. PMID: 32792907; PMCID: PMC7390928.
Camelo CG, Artilheiro MC, Martins Moreno CA, Ferraciolli SF, Serafim Silva AM, Fernandes TR, Lucato LT, Rocha AJ, Reed UC, Zanoteli E. Brain MRI Abnormalities, Epilepsy and Intellectual Disability in LAMA2 Related Dystrophy - a Genotype/Phenotype Correlation. J Neuromuscul Dis. 2023;10(4):483-492. doi: 10.3233/JND-221638. PMID: 37182895; PMCID: PMC10357150.

Palavras Chave

Congenital Muscular Dystrophy; LAMA2; brain MRI