Table 3.

Summary of diffusion tensor imaging studies included in our meta-analysis conducted in patients with major depressive disorder using corrected whole-brain voxel-based analysis^a

Study	Method	Participants	Results	Comments
Kieseppä et al. [18]	Voxel-based analysis 1.5 Tesla 12 non-colinear directions	16 middle-aged MDD patients and 20 controls	Reduced FA in the left sagittal stratum, cingulate cortex and posterior corpus callosum	Reduced FA in left SLF (temporoparietal) and in the right cingulum in patients with MDD
Zhu et al. [58]	TBSS 1.5 Tesla 13 non-colinear directions	25 young first-episode MDD patients and 25 matched controls	Reduced FA in the left anterior limb of the internal capsule, right parahippocampal gyrus and left posterior cingulate cortex	FA values in the left anterior limb of the internal capsule and right cingulum (hippocampus) and left cingulum (dorsal part) were negatively correlated with symptom severity
Abe et al. [59]	Voxel-based analysis 1.5 Tesla 6 non-colinear directions	21 young MDD patients and 42 controls	No significant difference between groups for FA and WM volume	Negative correlation between FA and total days depressed in both the right anterior cingulate and the left frontal WM
Blood et al. [24]	Voxel-based analysis 3.0 Tesla 6 non-colinear directions	22 MDD patients and 22 controls	Increased FA in the right ventral tegmental area and reduced FA in DLPFC WM in MDD subjects	Increased FA in right corticospinal tract, decreased FA in left corticospinal tract, right inferior FOF (frontal lobe), bilateral DLPFC, left SLF (temporal)
Wu et al. [25]	Voxel-based analysis 3.0 Tesla 13 non-colinear directions	23 single-episode, medication-naive MDD subjects and 21 controls	FA reduction in right SLF, right middle frontal and left parietal WM with MDD	Reduced FA in left SLF (parietal lobe) and right frontal WM with MDD
Jia et al. [26]	Voxel-based analysis 3.0 Tesla 15 non-colinear directions	52 MDD patients, 16 with and 36 without a history of suicide attempts, and 52 matched controls	Reduced FA in the left anterior limb of the internal capsule in suicide attempters relative to both nonattempters and controls	Reduced FA in bilateral SLF (parietal lobe) and cerebellum
Korgaonkar et al. [60]	Voxel-based analysis 3.0 Tesla 42 different diffusion orientations	29 MDD subjects and 39 controls	7.8% reduction in FA in the limbic system, DLPFC, thalamic projection fibres, and corpus callosum	Limbic-DLPFC-thalamic axis Dysfunction may be involved in MDD

^aMDD, major depressive disorder; FA, fractional anisotropy; SLF, superior longitudinal fasciculus; TBSS, tract-based spatial statistics; FOF, fronto-occipital fasciculus; DLPFC, dorsolateral prefrontal cortex; WM, white matter.