MR imaging and proton spectroscopy of neuronal injury in late-onset GM2 gangliosidosis.

Abstract

BACKGROUND AND PURPOSE:

Despite the ubiquity of G(M2) gangliosides accumulation in patients with late-onset G(M2) gangliosidosis (G(M2)G), the only clinical MR imaging-apparent brain abnormality is profound cerebellar atrophy. The goal of this study was to detect the presence and assess the extent of neuroaxonal injury in the normal-appearing gray and white matter (NAGM and NAWM) of these patients.

METHODS:

During a single imaging session, 9 patients with late-onset G(M2)G and 8 age-matched normal volunteers underwent the following protocol: (1) T1- and T2-weighted and fluid-attenuated inversion recovery MR images, as well as (2) multivoxel proton MR spectroscopy (1H-MR spectroscopy) to quantify the distribution of the n-acetylaspartate (NAA), creatine (Cr), and choline (Cho), were obtained.

RESULTS:

The patients' NAA levels in the thalamus (6.5 +/- 1.9 mmol/L) and NAWM (5.8 +/- 2.1 mmol/L) were approximately 40% lower than the controls' (P = .003 and P = .005), whereas the Cr and Cho reductions ( approximately 30% and approximately 26%) did not reach significance (P values of .06-.1). All cerebellar metabolites, especially NAA and Cr, were much (30%-90%) lower in the patients, which reflects the atrophy.

CONCLUSION:

In late-onset G(M2)G, NAA decreases are detectable in NAGM and NAWM even absent morphologic (MR imaging) abnormalities. Because the accumulation of G(M2) gangliosides can be reduced pharmacologically, 1H-MR spectroscopy might be a sensitive and specific for detecting and quantifying neuroaxonal injury and monitoring response to emerging treatments.

• Authors: Matilde Inglese, Annette O Nusbaum, Gregory M Pastores, John Gianutsos, Edwin H Kolodny, Oded Gonen
• Journal: AJNR. American journal of neuroradiology (AJNR Am J Neuroradiol) Vol. 26 Issue 8 Pg. 2037-42 (Sep 2005) ISSN: 0195-6108 [Print] United States
• PMID: 16155156 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Protons
• Aspartic Acid
• N-acetylaspartate
• Creatine

Topics

• Adult
• Aspartic Acid (analogs & derivatives, metabolism)
• Atrophy
• Axons (pathology)
• Brain (metabolism, pathology)
• Case-Control Studies
• Cerebellum (metabolism, pathology)
• Creatine (metabolism)
• Female
• Gangliosidoses, GM2 (diagnosis, metabolism)
• Humans
• Magnetic Resonance Imaging
• Magnetic Resonance Spectroscopy
• Male
• Middle Aged
• Neurons (pathology)
• Periaqueductal Gray (pathology)
• Protons
• Thalamus (metabolism)