Diagnostic accuracy of diffusion tensor imaging in amyotrophic lateral sclerosis: a systematic review and individual patient data meta-analysis.
OBJECTIVE
There have been a large number of case-control studies using diffusion tensor imaging (DTI) in amyotrophic lateral sclerosis (ALS). The objective of this study was to perform an individual patient data (IPD) meta-analysis for the estimation of the diagnostic accuracy measures of DTI in the diagnosis of ALS using corticospinal tract data.


METHODS
MEDLINE, EMBASE, CINAHL, and Cochrane databases (1966-April 2011) were searched. Studies were included if they used DTI region of interest or tractography techniques to compare mean cerebral corticospinal tract fractional anisotropy values between ALS subjects and healthy controls. Corresponding authors from the identified articles were contacted to collect individual patient data. IPD meta-analysis and meta-regression were performed using Stata. Meta-regression covariate analysis included age, gender, disease duration, and Revised Amyotrophic Lateral Sclerosis Functional Rating Scale scores.


RESULTS
Of 30 identified studies, 11 corresponding authors provided IPD and 221 ALS patients and 187 healthy control subjects were available for study. Pooled area under the receiver operating characteristic curve (AUC) was 0.75 (95% CI: 0.66-0.83), pooled sensitivity was 0.68 (95% CI: 0.62-0.75), and pooled specificity was 0.73 (95% CI: 0.66-0.80). Meta-regression showed no significant differences in pooled AUC for each of the covariates. There was moderate to high heterogeneity of pooled AUC estimates. Study quality was generally high. Data from 19 of the 30 eligible studies were not ascertained, raising possibility of selection bias.


CONCLUSIONS
Using corticospinal tract individual patient data, the diagnostic accuracy of DTI appears to lack sufficient discrimination in isolation. Additional research efforts and a multimodal approach that also includes ALS mimics will be required to make neuroimaging a critical component in the workup of ALS.
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA. compfun@umich.edu
Bradley R
BR
Foerster
Ben A
BA
Dwamena
Myria
M
Petrou
Ruth C
RC
Carlos
Brian C
BC
Callaghan
Cristina L
CL
Churchill
Mona A
MA
Mohamed
Claudia
C
Bartels
Michael
M
Benatar
Laura
L
Bonzano
Olga
O
Ciccarelli
Mirco
M
Cosottini
Cathy M
CM
Ellis
Hannelore
H
Ehrenreich
Nicola
N
Filippini
Mizuki
M
Ito
Sanjay
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Kalra
Elias R
ER
Melhem
Timothy
T
Pyra
Luca
L
Roccatagliata
Joe
J
Senda
Gen
G
Sobue
Martin R
MR
Turner
Eva L
EL
Feldman
Martin G
MG
Pomper
D000690:Amyotrophic Lateral Sclerosis / Q000175:diagnosis* / Q000453:epidemiology*; D003951:Diagnostic Errors / Q000706:statistics & numerical data*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods* / Q000706:statistics & numerical data*; D006801:Humans; D015995:Prevalence; D015203:Reproducibility of Results; D018570:Risk Assessment; D012680:Sensitivity and Specificity
Amyotrophic lateral sclerosis; diagnostic accuracy; diagnostic imaging; diffusion tensor imaging; magnetic resonance imaging; meta-analysis