Characteristics of heroin spongiform leucoencephalopathy detected by hydrogen magnetic resonance spectroscopy

Qiang CHEN; Bingxun LU; Liang ZHOU; Jia YIN; Jinggui SONG

ABSTRACT

BACKGROUND:

Point resolved spectroscopy (PRESS) or single-voxel spectroscopy (SVS) is always used in the previous researches of magnetic resonance spectroscopy (MRS) and its regions of interest are mainly located in focal zones which can be observed with magnetic resonance imaging (MRI); however, both of them cannot manifest the changes of focal marginal zone. Contrarily, hydrogen magnetic resonance spectroscopy (1H-MRS) can det ect the all regions of brain.

OBJECTIVE:

To observe the 1H-MRS manifestations of patients with heroin spongiform leucoencephalopathy (HSLE) so as to analyze metabolic regularities of N-acetyl aspartate (NAA), creatine (Cr) and bilineurine (Cho) in brain.

DESIGN:

Case-contrast observation.

SETTING:

Department of Neurology, Nanfang Hospital.

PARTICIPANTS:

Three HSLE patients including 2 males and 1 female who were diagnosed with clinical imaging were selected from the Department of Neurology, Nanfang Hospital from August 2005 to August 2006, and all of them were regarded as the case group. In addition, 10 healthy volunteers were regarded as the control group.

METHODS:

Siemens Megnetom Vision Plus 1.5T superconductive magnetic resonance (MR) system and standard head coil were used in this study, and then, all subjects were checked with 1H-MRS.MAIN OUTCOME

MEASURES:

Levels of NAA, Cr and Cho in white matter of frontal, parietal and occipital lobes, metabolic maps of them and ratios of NAA/Cr and Cho/Cr.

RESULTS:

All 13 subjects were involved in the final analysis. ① NAA level The level of NAA in white matter of frontal,parietal and occipital lobes of case 1 was lower than that of the subjects in the control group (79.50±21.65, 96.75±16.14,77.05±22.47; 146.07±15.49, 117.77±14.56, 120.83±16.02; P ＜ 0.05, 0.01); meanwhile, white matter of parietal lobes of case 2 and case 3 was also lower than that of subjects in the control group (87.50±7.89, 80.65±11.73, P ＜ 0.01). ② Cr level There were no significant differences of the Cr level of all subjects in both case group and control group (P＞ 0.05).③ Cho level Except white matter of frontal lobes in case 1, the level of Cho was lower in the case group than that in the control group (P ＜ 0.01). ④ Ratio of NAA/Cr was lower in the case group than that in the control group, and the radio of Cho/Cr was decreased remarkably. ⑤ Metabolic maps of NAA and Cr manifested a low signal in focal site. ⑥ Ratio of Cho/Cr was obviously reversed in focal marginal zone, but wave of lactic acid was not observed at the same time.

CONCLUSION:

The area with abnormal metabolites in HSLE patients showed by 1H-MRS is obviously larger than the visible lesion area showed by MRI.There are abnormal metabolites in the adjacent area of HSLE lesions.