Three-dimensional multivoxel spectroscopy of the healthy hippocampus—are the metabolic differences related to the location?

Ostojic, J.; Kozic, D.; Konstantinovic, J.; Covickovic-Sternic, N.; Mijajlovic, M.; Koprivsek, K.; Semnic, R.

doi:10.1016/j.crad.2009.11.011

« Previous Next »Clinical Radiology
Volume 65, Issue 4 , Pages 302-307, April 2010

Three-dimensional multivoxel spectroscopy of the healthy hippocampus—are the metabolic differences related to the location?

J. Ostojic
- Institute of Oncology Sremska Kamenica, Diagnostic Imaging Center, Institutski Put 4, 21204 Sremska Kamenica Republic of Serbia
- Guarantor and correspondent. Tel.: +381 214805610; fax: +381 214805602.
D. Kozic
- Institute of Oncology Sremska Kamenica, Diagnostic Imaging Center, Institutski Put 4, 21204 Sremska Kamenica Republic of Serbia
J. Konstantinovic
- Institute of Oncology Sremska Kamenica, Diagnostic Imaging Center, Institutski Put 4, 21204 Sremska Kamenica Republic of Serbia
N. Covickovic-Sternic
- Institute of Neurology, Clinical Center of Serbia, School of Medicine, University of Belgrade, Dr Subotića 6, 110000 Belgrade, Republic of Serbia
M. Mijajlovic
- Institute of Neurology, Clinical Center of Serbia, School of Medicine, University of Belgrade, Dr Subotića 6, 110000 Belgrade, Republic of Serbia
K. Koprivsek
- Institute of Oncology Sremska Kamenica, Diagnostic Imaging Center, Institutski Put 4, 21204 Sremska Kamenica Republic of Serbia
R. Semnic
- Institute of Oncology Sremska Kamenica, Diagnostic Imaging Center, Institutski Put 4, 21204 Sremska Kamenica Republic of Serbia

Received 7 July 2009; received in revised form 31 October 2009; accepted 8 November 2009.

Aim

The aim of this study was to determine the bilateral distribution of proton metabolites along the long axis of the hippocampus.

Materials and methods

Forty-one healthy volunteers were examined using a 1.5T magnetic resonance imaging system, using proton three-dimensional spectroscopic imaging (3D CSI) of the left and the right hippocampus separately. Three dominant signals were measured: choline (Cho), total creatine (tCr), and n-acetylaspartate (NAA) and expressed as ratios of Cho:tCr, NAA:tCr, NAA:Cho and NAA:(Cho+tCr). We compared the data from three hippocampal regions: head, body and tail.

Results

Lower NAA:tCr ratios were found in head compared with the body (p<0.05) and in the head compared with the tail (p<0.05) bilaterally. Lower NAA:Cho and NAA:(Cho+tCr) ratios were found in the head compared with the body (p<0.05), in the body compared with the tail (p<0.05), and in the head compared with the tail (p<0.05) bilaterally. There was no statistically significant difference between the left and the right hippocampus.

Conclusion

Ratios of NAA:tCr, NAA:Cho, and NAA:(Cho+tCr) in hippocampal tissue were significantly higher posteriorly than anteriorly. As the differences are present in healthy volunteers, the appearance in patients related to approximate voxel positioning within hippocampi may result in false-positive results.