Periventricular White Matter Injury by Primary Intraventricular Hemorrhage: A Diffusion Tensor Imaging Study

Objectives: Many diffusion tensor imaging (DTI) studies have described the effects of hydrocephalus on periventricular white matter in patients with normal pressure hydrocephalus. However, little is known about hydrocephalus following stroke. We investigated the effect of hydrocephalus on periventricular white matter in patients with hydrocephalus after an intracerebral hemorrhage (ICH) using DTI. Methods: Fourteen patients with ICH and hydrocephalus, and 17 age- and sex-matched normal control subjects were recruited. DTI parameters were estimated in six regions of interest (ROIs) in periventricular white matter: the anterior corona radiata, the posterior corona radiata, the genu of the corpus callosum, the splenium of corpus callosum, the anterior limb of the internal capsule, and the posterior limb of the internal capsule. Results: Mean fractional anisotropy of the anterior corona radiata in patients was significantly higher than in controls (p < 0.05), but apparent diffusion coefficient (ADC) was not different in the two groups (p > 0.05). No significant differences between fractional anisotropies and ADCs were observed in the other five ROIs (p > 0.05). Conclusions: The anterior corona radiata was found to be more compressed by hydrocephalus than the other five regions of periventricular white matter examined in patients with hydrocephalus following ICH. It is believed that the results of the present study will be useful for the diagnosis and management of hydrocephalus following stroke.

Objective To explore the correlation between apparent diffusion coefficient(ADC)and neonatal behavioral neurological assessment(NBNA) of newborns with hypoxic ischemic encephalopathy (HIE), and to evaluate ADC in the early diagnosis of HIE from the imaging perspective. Method One hundred and nine neonates aged 0—7 days with HIE underwent conventional MRI and DWI. According to HIE grading standards, there were 43 neonates in the mild group, 38 in the moderate group, 28 in the severe group, and meanwhile 24 normal neonates with the same ages were selected as the control group. All cases were assessed with NBNA, and ADC values of bilateral frontal white matter, parietal white matter, periventricular white matter, posterior limb of the internal capsule (PLIC), ventral lateral nucleus of thalamus, lenticular nucleus, splenium of the corpus callosum, brainstem were measured. ADC values of different groups were compared by analysis of variance, and the correlations between ADC values of all ROIs and NBNA were analyzed by Pearson correlation. Results Except lenticular nucleus and the brainstem, ADC values of frontal white matter, parietal white matter, periventricular white matter and PLIC, ventral lateral nucleus of thalamus, splenium of the corpus callosum were decreased in the mild, moderate, severe group. In the mild, moderate, and severe group, the ADC values of frontal deep white matter were (1.82±0.33)×10-3, (1.77±0.34)×10-3 and (1.62±0.31)×10-3 mm2/s, while they were (1.81±0.34)×10-3, (1.79±0.27)× 10-3 and (1.72±0.31)×10-3 mm2/s for the parietal deep white matter, (1.27±0.15)×10-3, (1.23±0.12)×10-3 and (1.15±0.17)×10-3 mm2/s for the periventricular white matter, (1.08±0.09)×10-3, (0.97±0.07)×10-3 and (0.84±0.06)×10-3 mm2/s for the PLIC, (1.13±0.07)×10-3, (1.08±0.13)×10-3 and (1.00±0.13)×10-3 mm2/s for the ventral lateral nucleus of thalamus, (1.27±0.22)×10-3, (1.18±0.16)×10-3 and (1.00±0.23)×10-3 mm2/s for the splenium of the corpus callosum. There were statistically significant differences between the 3 groups (F=61.27, 16.27, 23.26, 72.70, 26.73, 66.09, all P<0.05). In the mild, modreate and severe group, NBNA were (36.8±1.4) in the mild group, (33.5±1.6) in the moderate, and (29.3±2.6) in the severe group. There was positive correlation between ADC values of frontal white matter, parietal white matter, periventricular white matter and PLIC, ventral lateral nucleus of thalamus, splenium of the corpus callosum and NBNA scores (r=0.60, 0.49, 0.54, 0.67, 0.56, 0.65, all P<0.05). Conclusions There are correlations between ADC values of the related ROIs of HIE and NBNA scores. Combining two aspects might diagnose the brain injury of HIE more accurately and objectively. Key words: Diffusion magnetic resonance imaging; Infant, newborn; Hypoxia-ischemia, brain

Periventricular white matter injury is the common cause of spastic cerebral palsy. However, the early diagnosis of spastic cerebral palsy still remains a challenge. Our aim was to investigate whether infants with periventricular white matter injury with bilateral spastic cerebral palsy have unique lesions different from those in infants without cerebral palsy and to evaluate the efficiency of DTI in the early diagnosis of spastic cerebral palsy. Infants with periventricular white matter injury and controls underwent MR imaging at 6-18 months of age. Fractional anisotropy was calculated from DTI. Cerebral palsy was diagnosed by 24-30 months of age. Subjects were divided into 3 groups: infants with periventricular white matter injury with bilateral spastic cerebral palsy, infants with periventricular white matter injury without cerebral palsy, and controls. Tract-Based Spatial Statistics and Automated Fiber Quantification were used to investigate intergroup differences. Receiver operating characteristic curves were used to assess the diagnostic accuracy of spastic cerebral palsy. Correlations between motor function scores and fractional anisotropy were evaluated along white matter tracts. There were 20, 19, and 33 subjects in periventricular white matter injury with spastic cerebral palsy, periventricular white matter injury without cerebral palsy, and control groups, respectively. Decreased fractional anisotropy in the corticospinal tract was only observed in infants with periventricular white matter injury with spastic cerebral palsy, whereas decreased fractional anisotropy in the posterior thalamic radiation and genu and splenium of the corpus callosum was seen in both periventricular white matter injury subgroups. Fractional anisotropy in the corticospinal tract at the internal capsule level was effective in differentiating infants with periventricular white matter injury with spastic cerebral palsy from those without cerebral palsy by a threshold of 0.53, and it had strong correlations with motor function scores. Corticospinal tract lesions play a crucial role in motor impairment related to spastic cerebral palsy in infants with periventricular white matter injury. Fractional anisotropy in the corticospinal tract at the internal capsule level could aid in the early diagnosis of spastic cerebral palsy with high diagnostic accuracy.

Background: Brain injury in premature infants (BIPI) is a severe brain damage in premature infants, resulting in a series of neurological sequelae. Diffusion tensor imaging (DTI), as a magnetic resonance imaging (MRI) technique, is more widely used for premature infants. It is of paramount importance to improve the early diagnosis, treatment, and intervention for this population by using DTI. There are few reports on the application of DTI for the evaluation of BIPI in low-birth-weight (LBW) and very-low-birth-weight (VLBW) infants. Objectives: To analyze the clinical characteristics of BIPI in LBW and VLBW infants and to explore the value of MRI-based DTI in the evaluation of BIPI in LBW infants. Patients and Methods: This prospective study was conducted on 31 cases of BIPI (16 LBW and 15 VLBW infants) and 20 normal control premature infants, undergoing MRI-based DTI at the 37 - 40 weeks corrected gestational age (CGA). Differences in fractional anisotropy (FA) and apparent diffusion coefficient (ADC) between the BIPI and control groups and also between the LBW and VLBW groups with BIPI were analyzed. Also, differences with normal controls in terms of the FA and ADC values were investigated in different brain regions. Results: The FA values in the central white matter of the frontal lobe, central white matter of the occipital lobe, centrum semiovale, posterior limb of the internal capsule (PLIC), and ventral thalamus were significantly lower in the BIPI group as compared to the control group (P &lt; 0.05). The ADCs were lower in the BIPI group compared to the control group, and there was a significant difference (P &lt; 0.05). Comparison of FA and ADC values in the central white matter of the frontal lobe, central white matter of the occipital lobe, centrum semiovale, PLIC, and ventral thalamus did not show any significant differences between the LBW and VLBW groups with BIPI (P &gt; 0.05). Conclusion: The FA and ADC values of DTI can be used for the quantitative evaluation of BIPI in LBW and VLBW infants. The FA value was found to be more accurate than the ADC. Overall, different FA values in different brain areas reflect differences in the brain development of normal premature infants.

The aim is to investigate whether there is a microstructural change in the white matter pathways in patients with spontaneous intracranial hypotension (SIH). Additionally, the relationship between conventional magnetic resonance imaging (MRI) findings and diffusion tensor imaging (DTI) parameters is determined. Thirty patients diagnosed with SIH and 31 control patients (between January 2019 and February 2024) were included in the case-control study. MRI findings constituting the Bern score were evaluated in contrast-enhanced brain MRI. Ten different white matter pathways were evaluated with the following DTI parameters: fractional anisotropy (FA), apparent diffusion coefficient (ADC), axial diffusion (AD), and radial diffusion (RD). We also examined the association between MRI findings and DTI parameters. In the cingulum, a decreased FA value (Z = -3.18, p = 0.002) was observed in patients with SIH, indicating disruption of white matter integrity and weakened synaptic transmission in this region. In the corona radiata, significant reductions were observed in both FA (Z = -5.67, p < 0.001) and AD (Z = -3.59, p < 0.001), alongside an increase in RD (Z = -4.99, p < 0.001). The concomitant increase in RD further supports the idea of potential damage to the myelin sheath, which, together with other findings, may reflect disruptions in white matter architecture that underlie the cognitive and motor deficits frequently seen in patients with SIH. In the splenium of the corpus callosum, a significant reduction in AD (Z = -3.00, p = 0.007) was also noted. In the anterior limb of the internal capsule (ALIC), both FA (Z = -4.57, p < 0.001) and AD (Z = -2.73, p = 0.012) values decreased, while RD increased (Z = -2.93, p = 0.007). These alterations suggest the involvement of motor and sensory pathways. In the posterior limb of the internal capsule (PLIC), significant reductions were found in both FA (Z = -5.59, p < 0.001) and AD (Z = -3.82, p < 0.001), along with an increase in RD (Z = -5.49, p < 0.001). In the corticospinal tract, patients with SIH exhibited a decrease in FA (Z = -4.15, p < 0.001), an increase in ADC (Z = -2.87, p = 0.008), and an increase in RD (Z = -3.73, p < 0.001). These findings represent significant microstructural changes reflecting a reduction in the integrity of motor pathways in white matter. In the middle cerebellar peduncle (MCP), patients with SIH showed increased ADC (Z = -4.78, p < 0.001) and RD (Z = -3.23, p = 0.002). Similarly, in optic radiation, there was decreased FA (Z = -4.55, p < 0.001) and AD (Z = -2.59, p = 0.018), with increased RD (Z = -2.95, p = 0.007). In the correlation analysis, positive correlations were found between suprasellar distance and AD values in both the ALIC (rs = 0.451, p = 0.012) and MCP (rs = 0.416, p = 0.022). These findings suggest that structural changes and anatomical shifts, especially in the suprasellar region, may be associated with microstructural changes in the adjacent white matter pathways. We revealed microstructural changes in white matter in SIH. The alterations in DTI parameters may suggest that the white matter microarchitecture is changed as a result of mechanical compression of the axons in the white matter pathways due to brain prolapse and venous congestion.

Periventricular white matter injury (PWI) is a major form of brain injury observed in congenital hemiparesis. The aim of this study is to determine the usefulness of diffusion tensor imaging (DTI) and fibre tracking in delineating the primary and secondary degenerative changes in cerebral white matter and deep grey matter in patients with spastic cerebral palsy due to PWI and to look for any possible reorganization of the axonal architecture. Five hemiparetic cerebral palsy patients (median age 14 years) with known PWI were prospectively studied with DTI of the brain at 1.5T and quantitatively compared with five age and sex matched controls. Fibre tracts for various corticofugal, thalamocortical and association tracts were generated and analysed for the DTI fibre count and for diffusion parameters. A region of interest based analysis was performed for the directionally averaged mean diffusivity (D(av)) and fractional anisotropy (FA) values in various white matter locations in the brain and the brainstem and in the deep grey matter nuclei. Group statistics were performed for these parameters using Mann-Whitney U-test comparing the affected sides in patients with either side in controls and the unaffected side in hemiparetics. There was significant reduction in DTI fibre count on the lesional side involving corticospinal tract (CST), corticobulbar tract (CBT) and superior thalamic radiation in the patient group compared with controls. Also there was an increase in DTI fibre count in the unaffected side of the hemiparetic patients in CST and CBT, which reached statistical significance only in CBT. The corpus callosum, cingulum, superior longitudinal fasciculus and middle cerebellar peduncle failed to show any significant change. ROI measurements on the primary site of white matter lesion and the thalamus revealed a significant increase in D(av) and decrease in FA, suggesting primary degeneration. The CST in the brainstem, the body of corpus callosum and the head of caudate and lentiform nuclei showed features of secondary degeneration on the affected side. The CST on the unaffected side of hemiparetics was found to have a significant decrease in D(av) and an increase in FA. Thus the degeneration of various motor and sensory pathways, as well as deep grey matter structures, appears to be important in determining the pathophysiological mechanisms in patients with congenital PWI. Also evidence suggesting the reorganization of sensorimotor tracts in the unaffected side of spastic hemiparetic patients was noted.

Periventricular white matter injury (PVWMI) is the most common form of brain injury and the leading cause of cerebral palsy (CP). Early prediction of CP within the first 2 years of life is crucial for timely and effective intervention. Early CP prediction tools for infants with PVWMI are lacking. This study aimed to develop and validate a conventional Magnetic Resonance Imaging (MRI)-based model to predict CP in infants with PVWMI. In this multicentre retrospective cohort study in China, infants with PVWMI who underwent conventional MRI between 6 and 24 months of corrected age (CA) were included from five hospitals and confirmed to have CP or non-CP by 5 years of age. Between April 2013 and September 2018, a multivariable regression logistic model was developed and internally validated using data from one hospital to identify significant independent MRI features associated with CP, followed by external validation across four other hospitals. A visual nomogram was constructed based on these factors. Predictive performance was evaluated via the area under the receiver operating characteristic curve (AUC), calibration curves, and decision curves. Between October 2018 and January 2021, data from one hospital was included in a multiple readers test cohort (nine radiologists and two paediatric neurologists with varying experience) to assess the diagnostic performance and generalisability of the model. Subgroup analyses were conducted by age and sex. Across the two recruitment periods, 383 infants (65% male) with MRI-diagnosed PVWMI were included: 191 infants (122 with CP) in the derivation cohort, 115 (75 with CP) in the external validation cohort, and 77 (46 with CP) in the multiple readers test cohort. Five MRI features were associated with CP: abnormal signals in the posterior limb of the internal capsule (odds ratio [OR] 16.52; 95% confidence interval (CI) 5.78-52.67; P < 0.001), corticospinal tract in centrum semiovale (13.01; 3.49-62.30; P < 0.001), and cerebral peduncle (5.54; 1.20-32.15; P = 0.04), abnormal signals or atrophy in the thalamus (4.76; 1.41-19.32; P = 0.02) and lenticular nucleus (4.58; 1.24-21.35; P = 0.03). The model yielded an AUC of 0.94 (95% CI 0.91-0.98) in the derivation cohort. Similar AUCs were achieved in the internal (0.96 [0.93-0.99]) and external (0.92 [0.86-0.97]) validation cohorts. In the multiple readers test cohort, the average AUC, average sensitivity, and average specificity of 11 readers were 0.96 (95% CI 0.93-0.99), 0.90 (0.84-0.96), and 0.88 (0.77-0.98), respectively. Subgroup analyses were robust, yielding similar AUCs. The conventional MRI-based model showed good performance for predicting CP in infants aged 6-24 months with PVWMI and also had good diagnostic performance and generalisability, which may assist in identifying high-risk infants of CP and facilitating timely interventions. Future work with external validation in diverse countries and socioeconomic contexts are needed. National Natural Science Foundation of China, Key R&D Program of Shanxi Province, National Medical Centre Project of the First Affiliated Hospital of Xi'an Jiaotong University, Henan Provincial Health Commission National Traditional Chinese Medicine Clinical Research Base Scientific Research Special Fund, and Clinical Research Award of the First Affiliated Hospital of Xi'an Jiaotong University.

Objective To investigate the value of diffusion tensor imaging (DTI) at high b value for unilateral middle cerebral artery (MCA) occlusive disease in patients without obvious infarct lesions on conventional MR imaging.Methods DTI at high b value (2200 s/mm2 ) was performed using a 3.0 Tesla MR scanner in 34 patients with unilateral middle cerebral artery occlusion,who had no obvious infarct lesions on conventional MR imaging. Fractional anisotropy (FA),apparent diffusion coefficient (ADC),axial diffusivity (eigenvalue λ1) and radial diffusivity (eigenvalues λ2,λ3) were measured at the ipsilateral and contralateral corona radiata,anterior and posterior limbs of the internal capsule,cerebral peduncle and pons in all subjects.Mean ADC,FA,λ1,λ2 and λ3 values of corona radiata,anterior and posterior limbs of the internal capsule,cerebral peduncle and pons were compared between the ipsilateral and contralateral MCA territory by t test. Results Among the 34 patients,left MCA occlusion in M1 segment occurred in 16 patients and right MCA occlusion in Ml segment occurred in 18 patients.At the ipsilateral corona radiata,mean FA,ADC,λ1,λ2 and λ3 were 0.419 ±0.032,(5.975 ±0.272) × 10 3,(5.704 ±0.365) ×10-3,(6.412 ±0.368) × 10-3 and (6.605 ±0.343) × 10-3 mm2/s,respectively.At the contralateral corona radiata,mean FA,ADC,λ1,λ2 and λ3 were 0.443 ± 0.033,(5.804 ± 0.282) × 10 -3,(5.651 ±0.350) × 10-3,(6.099 ±0.353) × 10-3 and(6.372 ±0.355) × 10-3 mm2/s,respectively.At the ipsilateral corona radiata,mean FA was significantly decreased(t =11.614,P ＜0.01),and mean ADC (t=12.421,P＜0.01),λ1(t =7.447,P＜0.01),λ2(t=10.244,P＜0.01) and λ3(t=9.890,P＜0.01) were significantly increased.At the ipsilateral anterior and posterior limb of the internal capsule,mean FA were 0.609 ±0.026 and 0.674 ±0.033,λ1 were(5.330 ±0.462) × 10 -3 and(5.171 ±0.456) ×10-3 mm2/s,respectively.At the contralateral anterior and posterior limb of the internal capsule,FA were 0.622 ±0.026 and 0.694 ±0.034,λ1 were(5.064 ± 0.448) × 10 -3 and(4.924 ± 0.365) × 10 -3 mm2/s,respectively.Mean FA was significantly decreased (t =7.823,8.013,all P ＜ 0.01) and mean λ1 was significantly increased (t =7.811,8.800,all P ＜0.01) at the ipsilateral anterior and posterior limbs of the internal capsule.There was no significant difference in ADC,λ2 and λ3 value between the ipsilateral and contralateral sides.And all the DTI parameters,including mean ADC,FA,λ1,λ2 and λ3 values,showed no statistical difference between both sides of cerebral peduncle and pons.Conclusion DTI at high b valuc can provide useful information for visualizing ischemic white matter injury in patients without obvious infarct lesions on conventional MR imaging. Key words: Infarction, middle cerebral artery; Diffusion magnetic resonance imaging

Mild traumatic brain injuries (mTBIs) comprise 80% of all TBI, but conventional MRI techniques are often insensitive to the subtle changes and injuries produced in a concussion. Diffusion tensor imaging (DTI) is one of the most sensitive MRI techniques for mTBI studies with outcome and symptom associations described. The corpus callosum (CC) is one of the most studied fiber tracts in TBI and mTBI, but the comprehensive post-mTBI symptom relationship has not fully been explored. This is a retrospective observational study of how quantitative DTI data of the CC and its sub-regions may relate to clinical presentation of symptoms and timing of resolution of symptoms in patients diagnosed with uncomplicated mTBI. DTI and clinical data were obtained retrospectively from 446 (mean age 42 years, range 13-82) civilian patients. From patient medical charts, presentation of the following common post-concussive symptoms was noted: headache, balance issues, cognitive deficits, fatigue, anxiety, depression, and emotional lability. Also recorded was the time between injury and a visit to the physician when improvement or resolution of a particular symptom was reported. FA values from the total CC and 3 subregions of the CC (genu or anterior, mid body, and splenium or posterior) were obtained from hand tracing on the Olea Sphere v3.0 SP12 free-standing workstation. DTI data was obtained from 8 different 3T MRI scanners and harmonized via ComBat harmonization. The statistical models used to explore the association between regional Fractional Anisotropy (FA) values and symptom presentation and time to symptom resolution were logistic regression and interval-censored semi-parametric Cox proportional hazard models, respectively. Subgroups related to age and timing of first scan were also analyzed. Patients with the highest FA in the total CC (p = 0.01), anterior CC (p < 0.01), and mid-body CC (p = 0.03), but not the posterior CC (p = 0.91) recovered faster from post-concussive cognitive deficits. Patients with the highest FA in the posterior CC recovered faster from depression (p = 0.04) and emotional lability (p = 0.01). There was no evidence that FA in the CC or any of its sub-regions was associated with symptom presentation or with time to resolution of headache, balance issues, fatigue, or anxiety. Patients with mTBI under 40 had higher FA in the CC and the anterior and mid-body subregions (but not the posterior subregion: p = 1.00) compared to patients 40 or over (p ≤ 0.01). There was no evidence for differences in symptom presentation based on loss of consciousness (LOC) or sex (p ≥ 0.18). This study suggests that FA of the CC has diagnostic and prognostic value for clinical assessment of mTBI in a large diverse civilian population, particularly in patients with cognitive symptoms.

Perinatal brain injury in survivors of premature birth has a unique and unexplained predilection for periventricular cerebral white matter. Periventricular white-matter injury (PWMI) is now the most common cause of brain injury in preterm infants and the leading cause of chronic neurological morbidity. The spectrum of chronic PWMI includes focal cystic necrotic lesions (periventricular leukomalacia; PVL) and diffuses myelination disturbances. Recent neuroimaging studies support that the incidence of PVL is declining, whereas focal or diffuse noncystic injury is emerging as the predominant lesion. Factors that predispose to PVL during prematurity include hypoxia, ischemia, and maternal-fetal infection. In a significant number of infants, PWMI appears to be initiated by perturbations in cerebral blood flow that reflect anatomic and physiological immaturity of the vasculature. Ischemic cerebral white matter is susceptible to pronounced free radical-mediated injury that particularly targets immature stages of the oligodendrocyte lineage. Emerging experimental data supports that pronounced ischemia in the periventricular white matter is necessary, but not sufficient to generate PWMI. The developmental predilection for PWMI to occur during prematurity appears to be related to both the timing of appearance and regional distribution of susceptible oligodendrocyte progenitors. Injury to oligodendrocyte progenitors may contribute to the pathogenesis of PWMI by disrupting the maturation of myelin-forming oligodendrocytes. Chemical mediators that may contribute to white-matter injury include reactive oxygen species glutamate, cytokines, and adenosine. As our understanding of the pathogenesis of PWMI improves, it is anticipated that new strategies for directly preventing brain injury in premature infants will develop.

Increasing evidence demonstrates that there is marked damage and dysfunction in the white matter in Alzheimer's disease (AD). The present study investigates the nature of white matter damage of patients with Alzheimer's disease with diffusion tensor magnetic resonance imaging (DTI) and analyses the relationship between the white matter damage and the cognition function. DTI, as well as T1 fluid attenuated inversion recovery (FLAIR) and T2-FLAIR, was performed on probable patients of Alzheimer's disease, and sex and age matched healthy volunteers to measure the fractional anisotropy (FA) and mean diffusivity (MD) in the genu and splenium of the corpus callosum, anterior and posterior limbs of the internal capsule, and the white matter of frontal, temporal, parietal, and occipital lobes. FA was lower in the splenium of corpus callosum, as well as in the white matter of the frontal, temporal, and parietal lobes from patients with Alzheimer's disease than in the corresponding region from healthy controls and was strongly positive correlated with MMSE scores, whereas FA appeared no different in the anterior and posterior limbs of internal capsule, occipital lobes white matter, and the genu of corpus callosum between the patients and healthy controls. MD was significantly higher in the splenium of corpus callosum and parietal lobes white matter from patients than in that those from healthy controls and was strongly negative correlated with MMSE scores, whereas MD in the anterior and posterior limbs of internal capsule, as well as in frontal, temporal, occipital lobes white matter and the genu of corpus callosum, was not different between the patients and healthy controls. The most prominent alteration of FA and MD was in the splenium of corpus callosum. Our results suggested that white matter of patients with Alzheimer's disease was selectively impaired and the extent of damage had a strong correlation with the cognitive function, and that selective impairment reflected the cortico-cortical and cortico-subcortical disconnections in the pathomechanism of Alzheimer's disease. The values of FA and MD in white matter, especially in the splenium of corpus callosum in AD patients, might be a more appropriate surrogate marker for monitoring the disease progression.

Our objective was to characterize the structural and metabolic changes of the corticospinal tract (CST) in ALS patients using combined diffusion tensor imaging (DTI) and magnetic resonance spectroscopic imaging (MRSI). Fourteen patients (male:female, 6:8; mean age, 54 years) and 14 controls (male:female, 8:6; mean age, 53 years) underwent imaging. Four regions of the CST were evaluated: precentral gyrus, corona radiata, posterior limb of the internal capsule, and cerebral peduncle. DTI and MRSI indices tested included fractional anisotropy (FA), apparent diffusion coefficient (ADC), and the ratio of N-acetylaspartate to choline (NAA/Cho) and creatine (NAA/Cr). In the precentral gyrus, NAA/Cho was reduced 18% (p<0.001), NAA/Cr was reduced 9% (p=0.01), and FA was reduced 3% (p=0.02). NAA/Cho and NAA/Cr were reduced in the corona radiata (p<0.001). Reduced NAA/Cho in the precentral gyrus correlated with shorter symptom duration (r=0.66, p=0.02) and faster disease progression (r=-0.65, p=0.008). Increased spasticity correlated with higher ADC in the precentral gyrus (R=0.52, p=0.005). In conclusion, both MRSI and DTI provided in vivo evidence of intracranial degeneration of the CST in ALS that was most prominent rostrally in the precentral gyrus.

This study aimed to investigate the regional changes of brain white matter (WM) in DE patients using diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI). A total of 25 dry eye patients (PAT) and 25 healthy controls (HC) were recruited. All subjects underwent DTI and NODDI, fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), isotropic volume fraction (FISO), intra-cellular volume fraction (FICVF), and orientation dispersion index (ODI) were obtained respectively. Then complete Hospital Anxiety and Depression Scale (HADS), anxiety score (AS) or depression scores (DS) were obtained. Receiver operating characteristic (ROC) curve analysis was used to evaluate the reliability of DTI and NODDI in distinguishing the two groups. DTI revealed that PAT had lower FA in both the left superior longitudinal fasciculus (LSLF) and the corpus callosum (CC), and higher MD in the LSLF, the right posterior limb of the internal capsule and the right posterior thalamic radiation. PAT had significant AD changes in regions including the genu of the CC, the right posterior limb of internal capsule, and the right splenium of the CC. From NODDI, PAT showed increased ODI in the LSLF and increased FISO in the right splenium of the CC. FICVF showed a significant decrease in the LSLF while increased in the left anterior corona radiata and the CC. Furthermore, the average values of MD and FICVF were significantly correlated with DS and AS. Hence the results of this study suggest that there are regional changes in WM in DE patients which may contribute to further understanding of the pathological mechanism of DE.

Introduction: Intracerebral hemorrhage (ICH) is a devastating disease with poor outcome. Established predictive markers include initial hematoma size, clinical status, intraventricular bleeding and age. However, prognostic assessment is often difficult which additionally burdens patients and caregivers and complicates rehabilitation. Functional outcome especially relies on motor function which is correlated with the integrity of the Corticospinal Tract (CST). Diffusion Tensor (DT) Tractography allows visualization of the CST. However, sufficient data about the prognostic impact of quantitative CST assessment is lacking. Methods: We prospectively enrolled patients with spontaneous supratentorial ICH admitted between 08/2012 und 08/2015. Informed consent and ethical approval was obtained. MRI scan was performed on day 5±1. DT data was normalized to MNI Space and Q-Space diffeomorphic reconstruction was performed using DSI-studio. CST was reconstructed based on quantitative anisotropy (QA) using the CST region (JHU white matter atlas) as seeding region and cerebral peduncle as region of interest (ROI). Fractional Anisotropy (FA) and QA were analyzed in the seeding and ROI region and in the posterior limb of the internal capsule (PLIC). Dichotomized modified Rankin Scale on day 90 (favorable outcome = mRS 0-2) was assessed as primary outcome variable. Results: 33 patients, mean age 70.7 y (standard deviation (SD) 12.9), 12 male, 21 with lobar hemorrhage, mean ICH volume on admission 16.5 (SD 11.3) cm 3 were included. 16 patients had a favorable outcome on day 90 (median mRS 3 (IQR 1-3.5). Mean number of reconstructed CST fiber pathways ipsilateral to ICH was higher in patients with favorable outcome (11343 (SD 8201)) than in patients with unfavorable outcome (4868 (SD 3221), p=0.008). Median QA and FA values in the PLIC ipsilateral to ICH were also higher in patients with favorable outcome (QA: 18.9 (IQR 16.2-23.3) vs. 14.6 (IQR 11.7 - 17.7), p=0.016, FA: 0.49 (IQR 0.45-0.53) vs. 0.41 (IQR 0.38-0.49), p=0.026). Conclusion: Higher FA- and QA-values in the PLIC and higher numbers of CST fiber pathways ipsilateral to ICH seem to be associated with a favorable outcome. DT Imaging may turn out as a useful quantitative predictive marker in the acute phase of ICH.

Overweight or obese body habitus is associated with cognitive deficits, impaired brain function, gray matter atrophy, and white matter (WM) hyperintensities. However, few diffusion tensor imaging (DTI) studies have assessed WM integrity in relation to overweight or obese status. This study assessed relationships between body mass index (BMI) and values of DTI parameters among 51 normal-weight (lean), overweight and obese participants who were otherwise healthy. BMI correlated negatively with fractional anisotropy (FA) and axial eigenvalues (λ1) in the body of corpus callosum (CC), positively with mean diffusivity and radial eigenvalues (λ□) in the fornix and splenium of CC, and positively with λ1 in the right corona radiata (CR) and superior longitudinal fasciculus (SLF). These data indicate that BMI correlates negatively with WM integrity in the fornix and CC. Furthermore, the different patterns of BMI-related differences in DTI parameters at the fornix, body and splenium of the CC, and the right CR and SLF suggest that different biological processes may underlie BMI-related impairments of WM integrity in different brain regions.