Observational Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Psychiatr. Jun 22, 2017; 7(2): 121-127
Published online Jun 22, 2017. doi: 10.5498/wjp.v7.i2.121
Three-dimensional stereotactic surface projection in the statistical analysis of single photon emission computed tomography data for distinguishing between Alzheimer’s disease and depression
Eiji Kirino
Eiji Kirino, Department of Psychiatry, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan
Eiji Kirino, Department of Psychiatry, Juntendo University Shizuoka Hospital, Izunokuni-shi, Shizuoka 410-2211, Japan
Eiji Kirino, Juntendo Institute of Mental Health, Koshigaya-shi, Saitama 343-0032, Japan
Author contributions: Kirino E solely contributed to this paper.
Institutional review board statement: This study was reviewed and approved by the institutional review board of Juntendo University Shizuoka Hospital.
Informed consent statement: All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
Conflict-of-interest statement: The authors have no conflicts of interest to report.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Eiji Kirino, MD, PhD, Department of Psychiatry, Juntendo University Shizuoka Hospital, 1129 Nagaoka, Izunokuni-shi, Shizuoka 410-2211, Japan. ekirino@juntendo.ac.jp
Telephone: +81-55-9483111 Fax: +81-55-9485088
Received: January 30, 2017
Peer-review started: February 12, 2017
First decision: March 28, 2017
Revised: April 10, 2017
Accepted: May 3, 2017
Article in press: May 5, 2017
Published online: June 22, 2017
Abstract
AIM

To evaluate usefulness of single photon emission computed tomography (SPECT) with three-dimensional stereotactic surface projection (3D-SSP) in distinguishing between Alzheimer’s disease (AD) and depression.

METHODS

We studied 43 patients who presented with both depressive symptoms and memory disturbance. Each subject was evaluated using the following: (1) the Minimal Mental State Examination; (2) the Hamilton Rating Scale for Depression; (3) Clinical Global Impression-Severity scale (CGI-S); and (4) SPECT imaging with 3D-SSP.

RESULTS

The MMSE scores correlated significantly with the maximum Z-scores of AD-associated regions. CGI-S scores correlated significantly with the maximum Z-scores of depression-associated regions. Factor analysis identified three significant factors. Of these, Factor 1 could be interpreted as favouring a tendency for AD, Factor 2 as favouring a tendency for pseudo-dementia, and Factor 3 as favouring a depressive tendency.

CONCLUSION

We investigated whether these patients could be categorized as types: Type A (true AD), Type B (pseudo-dementia), Type C (occult AD), and Type D (true depression). The factor scores in factor analysis supported the validity of this classification. Our results suggest that SPECT with 3D-SSP is highly useful for distinguishing between depression and depressed mood in the early stage of AD.

Keywords: Alzheimer’s disease, Three-dimensional stereotactic surface projection, Single photon emission computed tomography, Pseudo-dementia, Depression

Core tip: The present study aimed to evaluate whether statistical analysis of single photon emission computed tomography images by three-dimensional stereotactic surface projection (3D-SSP) is useful for distinguishing between Alzheimer’s disease (AD) and depression. The Minimal Mental State Examination, the Hamilton Rating Scale for Depression, and Clinical Global Impression-Severity scale findings correlated significantly with the Z-scores of AD-associated and depression-associated regions as determined using 3D-SSP analysis. Furthermore, factor analysis identified three significant factors: Factor 1, a tendency for AD; Factor 2, a tendency for pseudo-dementia; and Factor 3, a depressive tendency.