Table 2 The main results of DTI studies
Publication | Numbers of patients/controls | Fractional anisotropy | Mean diffusivity or apparent diffusion coefficient | Radial and axial diffusivity | Main clinical correlations |
|---|---|---|---|---|---|
Abe et al., [64] | 7/11 | Low in parts of the right frontal lobe and in the left subcortical precentral area | Â | Â | Not available |
Agosta et al., [21] | 25/18 | Low in parts of CSTs, the CC, parts of the frontal lobe and parts of the temporal lobe | No difference | Â | Negative |
Bede et al., [75] | 27/42 | Low along CSTs, the CC, cerebellum, brainstem, occipital lobe and opercular and insular regions | Â | RD was low in the cerebellum, brainstem, occipital lobe and opercular and insular regions | Not available |
Canu et al., [23] | 23/14 | Low in subcortical parts of CSTs and other parts of the frontal lobe | Elevated in parts of the CSTs, left postcentral gyrus, left insula, parts of the left temporal lobe, right angular cortex, parts of the frontal lobe, CC, parts of the occipital lobe and parts of the cerebellum | Â | Correlation between MD in bilateral orbitofrontal region and DD |
Chapman et al., [67] | 21/21 | Low in the CC, corona radiata and PLIC | Â | RD was low in the CC, corona radiate and PLIC. AD was elevated in the left corona radiata and the internal and external capsules | Correlation between FA in parts of CC and ALSFRS-R and negative correlation with DD, correlation between RD in parts of CC and DD |
Ciccarelli et al., [45] | 26/41 | Low along CSTs, the CC, anterior limb of the internal capsule, external capsule, parts of frontal lobe WM and postcentral gyri | Â | Â | Correlation between DPR and FA in left cerebral peduncle, right PLIC, right corona radiate right WM adjascent to the precentral gyrus and CC |
Ding et al., [74] | 10/10 | Â | Elevated in the PLIC | Â | Not available |
Ellis et al., [51] | 22/20 | Low along CSTs | Elevated along CSTs | Â | Correlation between mean diffusivity in CST and DD and between FA along CSTs and ALS severity scale and spasticity scales. |
Filippini et al., [56] | 24/24 | Low along CSTs and in the CC | Â | Elevated RD in WM linked to the primary motor and premotor cortex and the CC | Inverse correlation between FA and UMN score along CSTs, correlation between FA and ALSFRS-R and DD along CSTs |
Foerster et al., [55] | 29/30 | Low along CSTs | Â | Â | Correlation between FA and ALSFRS-R along CSTs |
Iwata et al., [49] | 31/31 | Low along CSTs | Â | Â | Negative |
Iwata et al., [50] | 18/19 | Low along CSTs and in the motor part of the CC | Elevated along CSTs | Â | Correlation between DD and FA along CSTs. Inverse correlation between FA in CSTs and global and localized UMN impairment score and between FA along CST and UMN rapidity index. |
111/74 | Low along CSTs | Â | Â | Not available | |
Keil et al., [61] | 24/24 | Low in parts of CSTs, supplementary motor area, CC, parts of the frontal lobe and the parahippocampal area | Elevated in motor areas, parts of CSTs, parts of the frontal and temporal lobe, and the postcentral gyrus | Â | Correlation between FA along CSTs and ALSFRS-R. Correlation between executives functions (sfs36 score) and FA in cerebellum. At 6Â months, negative correlation between FA along CSTs and DD correlation between FA along CSTs and frontal WM and ALSFRS-R. Correlation between FA in CST at brainstem level and executives functions, negative correlation between ADC in the cerebellum and parahippocampal gyri and executives functions (sfs36) |
Keller et al., [68] | 33/30 | Low in the corona radiata and CC | Â | Â | Negative |
Liu et al., 2014 | 19/13 | Low along CSTs | Â | Â | Correlation between FA along left CST and ALSFRS-R |
Menke et al., [77] | 21/0 (follow-up study) | Progressive reduction in the PLIC | Â | Â | Correlation between FA at baseline and DPR |
Metwalli et al., [69] | 12/19 | Low along CSTs, the CC | Elevated along CSTs, the CC | AD and RD were elevated along CSTs, RD was elevated in the CC, parts of frontal and parietal lobe | Negative |
Muller et al., 2011 | 19/19 | Low in parts of CSTs, the parahippocampal area, insula and brainstem | Â | Â | Correlation between FA in parts of CSTs and ALSFRS-R |
Nickerson et al., [46] | 2/0 (follow-up study) | A linear reduction along CSTs during one year follow-up | Â | Â | Not available |
Poujois et al., [65] | 19/21 | Low in CSTs from the left corona radiate to the precentral gyrus and in both cerebral peduncles | Â | Â | Muscular strength is lower on the right side corresponding to the lower FA in the left CST |
Prell et al., [60] | 17/17 | Low in parts of CSTs and the cingulate gyrus | Elevated parts of CSTs, parts of frontal lobe, cingulate gyrus, parahippocampal region, CC, cerebellum. | Â | Correlation between FA in internal capsule and contralateral strength of the lower limb. Different patterns in FA and ADC of bulbar and limb onset compared to controls. |
Prudlo et al., [70] | 22/21 | Low throughout the CSTs, the anterior limb of the internal capsule, thalamic radiations, the CC, association fibres and the middle cerebellar peduncle | Â | Â | Correlation between FA in many voxels of a whole DTI brain analyses with ALSFRS-R |
Pyra et al., [59] | 14/14 | Low in left precentral gyrus | Â | Â | Correlation between spasticity and ADC in contralateral precentral gyrus |
Rajagopalan et al., [63] | 47/10 | Low in the left subcortical motor area and right PLIC | Â | AD was low in the PLIC. RD was elevated in the PLIC of patients with T2 hyperintensities in the CSTs | Not available |
Rosskopf et al., [57] | 100/93 | Low along CSTs | Â | Â | Correlation between FA along CSTs and ALSFRS-R |
Sach et al., [33] | 15/12 | Low in parts of CSTs, premotor areas, CC and right thalamus | Â | Â | Low FA in patients without UMN signs in parts of CST, CC and right thalamus. No correlation available with clinical score |
Sage et al., [34] | 28/26 | Low along CSTs and the right postcentral gyrus | Elevated in parts of CSTs | Â | Correlation between FA and ALSFRS in several parts of CSTs and in prefrontal lobe |
Sage et al., [52] | 28/26 | Low in parts of CSTs, parts of the frontal lobe, insula, hippocampus, cerebral peduncles and CC | Elevated along CSTs, hippocampus, insula, parts of the temporal and frontal lobe and CC | Â | Correlation between FA along CSTs, in prefrontal area and ALSFRS. Negative correlation between MD along CST, hippocampus, cerebellum, parietal and temporal lobe and ALSFRS. |
Sarica et al., [53] | 14/14 | Low in right CSTs and left anterior thalamic radiations | Elevated in right CSTs, cingulum and left anterior thalamic radiations | RD elevated in right CSTs and left anterior thalamic radiations. AD elevated in the right cingulum | Negative (p ≤ 0.05) |
Schirimrigt et al., 2007 | 10/20 | Low along CSTs (nb: study with a technical objective) | Â | Â | Correlation between FA along CSTs and DD |
Stagg et al., [47] | 13/14 | Low along CSTs | Elevated along CSTs | Â | Negative |
Tang et al., [58] | 69/23 | Low along CSTs, in frontal WM and the genu of the CC | Elevated in the centrum semi-ovale and frontal and parietal WM | Â | Not available |
Thivard et al., [24] | 15/25 | Low along CSTs, premotor cortex, right thalamus, insula, parts of parietal lobe | Elevated in the motor cortex, premotor cortex, insula, hippocampus, and right superior temporal gyrus | Â | Correlation between FA along CST, insula, premotor cortex, cingulum, precuneus, CC and ALSFRS-R, negative correlation between FA in CC and centrum semiovale and DD |
Verstraete et al., [30] | 12/12 | Low in the rostral part of CSTs and the CC | Â | Â | Not available |
Wang et al., [71] | 16/17 | Low CST volume in DTI | Â | Â | Negative |
Yin et al., [48] | 8/12 | Low along CSTs | Â | Â | Not available |
Zhang et al., [62] | 17/19 | Low in parts of CSTs | Elevated in parts of the CSTs | Â | Correlation between FA in right superior CST and ALSFRS-R and motor subscore of ALSFRS-R |