Wilson's disease: 31P and 1H MR spectroscopy and clinical correlation

Proton (H-1) magnetic resonance spectroscopy (MRS) changes are noted in Wilson's disease (WD). However, there are no studies regarding membrane phospholipid abnormality using P-31 MRS in these patients. We aimed to analyze the striatal spectroscopic abnormalities using P-31 and H-1 MRS in WD. Forty patients of WD (treated, 29; untreated,11) and 30 controls underwent routine MR image sequences and in vivo 2-D P-31 and H-1 MRS of basal ganglia using an image-selected technique on a 1.5-T MRI scanner. Statistical analysis was done using Student's t test. The mean durations of illness and treatment were 6.2 +/- 7.4 and 4.8 +/- 5.9 years, respectively. MRI images were abnormal in all the patients. H-1 MRS revealed statistically significant reduction of N-acetyl aspartate (NAA)/choline (Cho) and NAA/creatine ratios in striatum (H-1 MRS) of treated patients compared to controls. The mean values of phosphomonoesters (PME) (p < 0.0001), phosphodiesters (PDE) (p < 0.0001), and total phosphorus (TPh) (p < 0.0001) were elevated in patients compared to controls. Statistically significant elevated levels of ratio of PME/PDE (p = 0.05) observed in the striatum were noted in treated patients as compared to controls in the P-31 MRS study. The duration of illness correlated well with increased PME/PDE [p < 0.001], PME/TPh [p < 0.05], and PDE/TPh [p < 0.05] and decreased NAA/Cho [p < 0.05] ratios. There was correlation of MRI score and reduced NAA/Cho ratio with disease severity. The PME/PDE ratio (right) was elevated in the treated group [p < 0.001] compared to untreated group. There is reduced breakdown and/or increased synthesis of membrane phospholipids and increased neuronal damage in basal ganglia in patients with WD.