title: Monitoring glutamate levels in the posterior cingulate cortex of thyroid dysfunction patients with TE-averaged PRESS at 3T.
abstract: OBJECTIVE
  Patients with thyroid dysfunction frequently have neuropsychiatric complaints such as lack of concentration, poor memory, depression, anxiety and mania, which suggest brain dysfunction. However, the underlying process of this dysfunction remains unclear. Recent studies of the glutamatergic system have offered important insight into the neuropsychiatric process. Thus, this study investigates changes in glutamate concentration in patients with thyroid dysfunction. It also clarifies whether Glu levels are related to thyroid hormones via proton magnetic resonance spectroscopy.
  
  
  METHODS
  36 untreated patients with thyroid dysfunction (18 hyperthyroidism patients and 18 hypothyroidism patients) and 18 age- and gender-matched controls were included in this study. The posterior cingulate cortex was examined by MRS with TE-averaged PRESS at 3T. The intensity of glutamate, choline, N-acetylaspartate, and creatine was assessed using jMRUI v4.0 software.
  
  
  RESULTS
  We found a significant difference among hyper-/hypo- and control groups in Glu (P=0.003) and Cho (P=0.015). The concentrations of glutamate increased (P=0.006) in the posterior cingulate cortex in patients with hypothyroidism and significantly decreased (P=0.002) in hyperthyroidism patients relative to controls. There were no difference in the concentrations of choline between hyperthyroidism patients and controls (P=0.679). Versus the hyperthyroidism group, the hypothyroidism group showed increased glutamate (P=0.018) and choline (P=0.001) in the posterior cingulate cortex. There was no significant difference in the concentrations of NAA or creatine across the three groups (P>0.05). The Glu level correlates with TT3 (P=0.000) and FT3 (P=0.022).
  
  
  CONCLUSIONS
  The signal intensity of glutamate shows significant differences in the region of the posterior cingulate cortex in patients with thyroid dysfunction. This change indicates a potential role of glutamate in the brain dysfunction experience by patients with thyroid hormone disorders.
authors: Department of Radiology, 2(nd), Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaaxi Province, P.R. China, 710004.
authors: Qiujuan
authors: Q
authors: Zhang
authors: Department of Radiology, 2(nd), Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaaxi Province, P.R. China, 710004. Electronic address: baizhilan_xjtu@163.com.
authors: Zhilan
authors: Z
authors: Bai
authors: Department of Radiology, 2(nd), Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaaxi Province, P.R. China, 710004.
authors: Yan
authors: Y
authors: Gong
authors: Department of Radiology, 2(nd), Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaaxi Province, P.R. China, 710004.
authors: Xinxin
authors: X
authors: Liu
authors: Department of Radiology, 2(nd), Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaaxi Province, P.R. China, 710004.
authors: Xiaoqing
authors: X
authors: Dai
authors: Department of Nuclear Medicine, 2(nd), Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaaxi Province, P.R. China, 710004.
authors: Shejiao
authors: S
authors: Wang
authors: Electronic and Information Engineering School of Xi'an Jiaotong University, Xi'an, China.
authors: Feng
authors: F
authors: Liu
mesh_terms: D000328:Adult; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism*; D006179:Gyrus Cinguli / Q000378:metabolism*; D006801:Humans; D008297:Male; D066244:Proton Magnetic Resonance Spectroscopy; D013959:Thyroid Diseases / Q000378:metabolism*; D013961:Thyroid Gland / Q000378:metabolism*
chemical_list: D001224:Aspartic Acid; D018698:Glutamic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline
keywords: Glutamate; Hyperthyroidism; Hypothyroidism; Magnetic resonance spectroscopy; TE-averaged PRESS; Thyroid dysfunction