1. 1H MRS Characteristics of Cerebral alveolar echinococcosis

2. WANG-Jian*，YI Ba-nu，JIANG Chun-hui，et al.
Imaging Center, First Affiliated Hospital，Xinjiang Medical University, Urumqi，830011, China

3. 1
Background 2
Methods 3
Results 4
Discussion
/ Conclusion 3 3

4. Background
Alveolar Echinococcosis(AE) is regarded as one of the most deadly worm infections. Xinjiang has one of the highest global incidences of AE. The most common primary site of AE is the liver. The incidence of extra hepatic metastasis is around 20％，and it is most commonly occurs in the lung and brain.
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4. Zhang YF, Xie ZR, Ni YQ, Mao R, Qi HZ, Yang YG, et al. Curative effect of radiotherapy at various doses on subcutaneous alveolar echinococcosis in rats. Chin Med J 2011; 124:

5. Cerebral Alveolar Echinococcosis（CAE) is a disease that grows infiltratively like a malignant tumor, it is harmful to human body. As the imaging features of CAE are not typical and immunization examination of hydatid disease has false negative/positive results, this kind of disease has a high rate of misdiagnosis-before- surgery.
FU Qiang，ZHOU Qingjiu，LIU Bo，etal. Diagnosis of cerebral echinococcosis and analysis on the cause of misdiagnosis. Chinese journal of neurosurgery disease research. 2010, 9:58-62

6. 1HMRS is currently the only non-invasive method for the study of in vivo tissues and organs of metabolism and biochemical changes in the human body.

7. This research focused on using proton magnetic resonance spectroscopy (1HMRS) technology to find the characteristics of CAE, In order to improve  the accuracy of preoperative diagnosis.

8. Materials and Methods
13 patients with 33 lesions histologically and clinically proven to be CAE were examined by convenational MRI and 2D multi-voxel spectra.

9. Materials and Methods GE singa HDx 3.0T MRI scanner
8 channel array head coil
GE AWD 4.4 Advanted image postprocessing workstation
GE Function Tool post-process software
2D multi-voxel 1HMRS(point resolved
selective spectroscopy (PRESS).

10. Concentrations of the metabolites containing N-acetyl-aspartic-acid (NAA), Choline (Cho), Creatine (Cr), lipids and lactic acid (Lip＋Lac), myo-Inositol(mI) and the value of Cho/Cr, NAA/Cr, (Lip＋Lac)/Cr，mI/Cr were calculated. Concentrations of the metabolites changes were compared in the substantial region with the relative contralateral part of the normal brain parenchyma area (control group). The data were statistically analyzed.

11. Results
The value of the 4 group pair-wise comparisons for all above measurements were statistically significant (P<0.001) between the substantial region (lesion) and the control group.

12. FIG 1. Cho, NAA decreased to varying degrees in CAE 1H MR spectrum, and were shown as a large lipid with or without lactate peak .

13. CAE reproduce invasively like a malignant tumor
CAE reproduce invasively like a malignant tumor. Mass vesicles around the alveolar hydatid survive. Compare with previous morphological imaging, 1HMRS can study the human body on a more micro-depth molecular level.

14. NAA, Cho（ Choline ）
In the research, the substantial region of CAE all displayed a decline in concentrations of NAA and Cho . It caused the destruction of the neurons.It showed that the lesion of CAE was infringed.

15. Lip and Lac ( lipids and lactic acid )
This study showed that the (Lip+Lac) of the substantial region of CAE significantly increased. Lip can reflect the existence of degeneration and necrosis, from the macrophages at the edge of the lesions or degenerated necrosis tissue cells. It decomposed the adipose structure of brain into a small molecular lipid, thus leading to increased Lip. A rise in concentrations of (Lip+Lac) and (Lip+Lac) /Cr suggests that CAE infringed upon the substantial region of CAE, and was metabolically exuberant.

16. Differential diagnosis
Although CAE reproduces invasively like a malignant tumor , it is inflammatory granuloma in nature. Cells of malignant tumors, such as high-grade glioma(WHO Ⅲ-Ⅳ grade) and metastatic tumor, have significant atypia high ratio of nucleoplasm. As a result, the Cho increases significantly. This is different from CAE. Malignant tumors often are combined with necrosis and Lip may increase as well.

17. CAE 1HMRS spectrum characteristics
key point of Differential diagnosis
CAE 1H MRS spectrum characteristics :
Cho, NAA decreased to varying degrees in CAE 1H MR spectrum, and were shown as a large lipid with or without lactate peak . This is the key point to differentiate malignant glioma and metastatic tumor.

18. 1H MRS can reflect pathological characteristics of CAE
1H MRS can reflect pathological characteristics of CAE. It provides metabolic information for diagnosis of CAE and may be a necessary supplement of conventional MRI. In the future, 1HMRS will provide more valuable information for CAE.

19. Acknowledgement

20. Thank you for your attention!