Proton magnetic resonance spectroscopy may predict future brain lesions in SLE patients: a functional multi-imaging approach and follow up

Abstract

Objective: To determine whether single photon emission tomography (SPECT) and magnetic resonance spectroscopy ( 1 H-MRS) can predict the appearance of new lesions in systemic lupus erythematosus (SLE), detectable by magnetic resonance imaging (MRI). Methods:99 Tc m -HMPAO-SPECT, brain MRI, and 1 H-MRS were done in eight women with SLE (mean age 31.8 years; disease duration 5.5 years). NAA/Cho, NAA/Cre, and Cho/Cre ratios were assessed in hypoperfused and normoperfused areas detected by SPECT that were normal on MRI examination. Reference values were obtained in 20 normal healthy controls. In five patients, MRI was repeated four to six years after the first evaluation. Results: Mean NAA/Cho and Cho/Cre ratios in hypoperfused and normoperfused frontal areas were, respectively, lower and higher than control. There were no differences in NAA/Cre ratios. Mean Cho/Cre ratios were increased in hypoperfused v normoperfused brain areas (mean (SD): 1.43 (0.27) v 1.00 (0.07); p,0.023). NAA/Cre ratios were not altered (2.18 (0.30) v 1.99 (0.28); p = 0.381). Three of five patients who had a second MRI had new lesions in areas previously abnormal on MRS and SPECT but normal on first MRI. One patient with positive MRI, SPECT, and MRS showed an increase in the number of MRI lesions; one patient with negative MRI, SPECT, and MRS did not show any new lesions. Conclusions: Abnormalities reflecting altered perfusion or neuronal-chemical changes can be demonstrated by functional imaging techniques even in the absence of morphological lesions detectable by MRI. The abnormal areas identified by SPECT and MRS may predict future parenchymal damage.

Localization of cerebral functional deficits in patients with non‐neuropsychiatric systemic lupus erythematosus

“…However, the structural MRI has been found to be of limited value in patients with diffuse neuropsychiatric disturbances such as headache, cognitive dysfunction, affective disorders, and confusional states [Rozell et al, 1998;Sabet et al, 1998]. Multiple functional neuroimaging modalities have therefore been used in SLE, including 1 H-magnetic resonance spectroscopy (MRS) [Castellino et al, 2005], SPECT [Appenzeller et al, 2007a], and fMRI [DiFrancesco et al, 2007;Fitzgibbon et al, 2008;Rocca et al, 2006]. These studies have suggested that functional alterations could precede structural changes in NP-SLE [Castellino et al, 2005], and, moreover, they allowed differentiation between patients with or without active CNS involvement [Appenzeller et al, 2007a].…”

“…Multiple functional neuroimaging modalities have therefore been used in SLE, including 1 H-magnetic resonance spectroscopy (MRS) [Castellino et al, 2005], SPECT [Appenzeller et al, 2007a], and fMRI [DiFrancesco et al, 2007;Fitzgibbon et al, 2008;Rocca et al, 2006]. These studies have suggested that functional alterations could precede structural changes in NP-SLE [Castellino et al, 2005], and, moreover, they allowed differentiation between patients with or without active CNS involvement [Appenzeller et al, 2007a]. Moreover, NP-SLE patients exhibited greater activation of specific cerebral regions than healthy controls in tasks of working memory [Fitzgibbon et al, 2008], motor control [Rocca et al, 2006], and attention and language processing [DiFrancesco et al, 2007], possibly indicative of functional compensation in NP-SLE patients that could reflect impairment of cerebral functions relating to these tasks.…”

Antiphospholipid Syndrome and Cognition

“…This study did include APS patients and corroborated the impression of subclinical neuronal damage induced by disease activity [15]. When multimodal imaging techniques are used assessing not only neurometabolic patterns (MR spectroscopy), but also perfusion (SPECT) and morphological abnormalities (conventional MRI), the predictive power seems to be increased and might be justified in selected clinical cases in an attempt to modify the course of the disease [16].…”

Neuroimaging - Clinical Applications

“…In that study metabolic changes at the basal ganglia, besides the normal appearing white matter, was also found, indicating small vessel injury. Reduction of NAA/Cr ratio and elevation of Cho/Cr ratio in normal appearing white matter, related to the severity of neuropsychiatric symptoms was also proved by others (Axford et al, 2001;Handa et al, 2003;Castellino et al, 2005). Axford and co-workers also performed quantitative absolute assessment of the metabolites and found increased absolute concentration of mI in NPSLE patients symptoms, that could be the result of inflammation, with a trend to be reversible in patients with minor.…”