Structural Characteristic of the Arcuate Fasciculus in Patients with Fluent Aphasia Following Intracranial Hemorrhage: A Diffusion Tensor Tractography Study

This study investigated the relationship between the structural characteristics of the left arcuate fasciculus (AF) reconstructed using diffusion tensor image (DTI) and the type of fluent aphasia according to hemorrhage lesions in patients with fluent aphasia following intracranial hemorrhage (ICH). Five patients with fluent aphasia following ICH (three males, two females; mean age 55.0 years; range 47 to 60 years) and with sixteen age-matched heathy control subjects were involved in this study. The ICHs of patients 1 and 2 were located in the left parietal lobe and the left basal ganglia. ICHs were located in the left anterior temporal of patient 3, the left temporal lobe of patient 4, and the left frontal lobe of patient 5. We assessed patients’ language function using K-WAB (the Korean version of the Western Aphasia Battery) and reconstructed the AF using DTI. We measured DTI parameters including the fractional anisotropy (FA), tract volume (TV), fiber number (FN), and mean diffusivity (MD). All patients showed neural tract injury (the decrement of FA, TV, and FN and increment of MD). The left AFs in patients 1 and 2 were shifted from Broca’s and Wernicke’s territories. The destruction of Wernicke’s territory resulted in conduction or transcortical sensory aphasia in patients 3 and 4. The structural difference of the AF in patients following ICH in the left hemisphere was associated with various types of fluent aphasia.

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Sensory processing sensitivity and axonal microarchitecture: Identifying brain structural characteristics for behavior

10.1101/2021.11.13.468491 ◽

2021 ◽

Author(s):

Szabolcs David ◽

Lucy L Brown ◽

Anneriet M Heemskerk ◽

Elaine Aron ◽

Alexander Leemans ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Sensory Processing ◽

Diffusion Tensor ◽

Structural Characteristics ◽

Inferior Frontal Gyrus ◽

Mean Diffusivity ◽

Human Connectome Project ◽

Sensory Processing Sensitivity ◽

The Right

Previously, researchers used functional MRI to identify regional brain activations associated with sensory processing sensitivity (SPS), a proposed normal phenotype trait. To further validate SPS as a behavioral entity, to characterize it anatomically, and to test the usefulness in psychology of methodologies that assess axonal properties, the present study correlated SPS proxy questionnaire scores (adjusted for neuroticism) with diffusion tensor imaging measures. Participants (n=408) from the Young Adult Human Connectome Project that are free of neurologic and psychiatric disorders were investigated. We computed mean diffusivity (MD), radial diffusivity (RD), axial diffusivity (AD) and fractional anisotropy (FA). A voxelwise, exploratory analysis showed that MD and RD correlated positively with SPS proxy scores in the right and left subcallosal and anterior ventral cingulum bundle, and the right forceps minor of the corpus callosum (peak Cohens D effect size = 0.269). Further analyses showed correlations throughout the entire right and left ventromedial prefrontal cortex, including the superior longitudinal fasciculus, inferior fronto-occipital fasciculus, uncinate and arcuate fasciculus. These prefrontal regions are generally involved in emotion, reward and social processing. FA was negatively correlated with SPS proxy scores in white matter of the right premotor/motor/somatosensory/supramarginal gyrus regions, which are associated with empathy, theory of mind, primary and secondary somatosensory processing. Region of interest (ROI) analysis, based-on previous fMRI results and Freesurfer atlas-defined areas, showed small effect sizes, (+0.151 to -0.165) in white matter of the precuneus and inferior frontal gyrus. Other ROI effects were found in regions of the dorsal and ventral visual pathways and primary auditory cortex. The results reveal that in a large, diverse group of participants axonal microarchitectural differences can be identified with SPS traits that are subtle and in the range of typical behavior. The results suggest that the heightened sensory processing in people who show SPS may be influenced by the microstructure of white matter in specific neocortical regions. Although previous fMRI studies had identified most of these general neocortical regions, the DTI results put a new focus on brain areas related to attention and cognitive flexibility, empathy, emotion and low-level sensory processing, as in the primary sensory cortex. Psychological trait characterization may benefit from diffusion tensor imaging methodology by identifying influential brain systems for traits.

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Diffusion MRI Changes in the Healthy Aging Canine Brain

10.1101/2020.10.05.327205 ◽

2020 ◽

Author(s):

Erica F. Barry ◽

John P. Loftus ◽

Wen-Ming Luh ◽

Mony J. de Leon ◽

Sumit N. Niogi ◽

...

Keyword(s):

White Matter ◽

Diffusion Mri ◽

Healthy Aging ◽

Parietal Lobe ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Human Aging ◽

Age Related ◽

Age Related Changes

AbstractWhite matter dysfunction and degeneration have been a topic of great interest in healthy and pathological aging. While ex vivo studies have investigated age-related changes in canines, little in vivo canine aging research exists. Quantitative diffusion MRI such as diffusion tensor imaging (DTI) has demonstrated aging and neurodegenerative white matter changes in humans. However, this method has not been applied and adapted in vivo to canine populations. This study aimed to test the hypothesis that white matter diffusion changes frequently reported in human aging are also found in aged canines. The study used Tract Based Spatial Statistics (TBSS) and a region of interest (ROI) approach to investigate age related changes in fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AxD) and radial diffusivity (RD). The results show that, compared to younger animals, aged canines have significant decreases in FA in parietal and temporal regions as well as the corpus callosum and fornix. Additionally, AxD decreases were observed in parietal, frontal and midbrain regions. Similarly, an age-related increase in RD was observed in the right parietal lobe while MD decreases were found in the midbrain. These findings suggest that canine samples offer a model for healthy human aging as they exhibit similar white matter diffusion tensor changes with age.

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Delayed development of aphasia related to degeneration of the arcuate fasciculus in the dominant hemisphere nine years after the onset in a patient with intracerebral hemorrhage: a case report

BMC Neurology ◽

10.1186/s12883-021-02199-4 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Min Jye Cho ◽

Sung Ho Jang

Keyword(s):

Intracerebral Hemorrhage ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Magnetic Resonance Images ◽

Arcuate Fasciculus ◽

Dominant Hemisphere ◽

Neural Degeneration ◽

Delayed Development ◽

Hemosiderin Deposits ◽

Post Onset

Abstract Background We report on a patient with an intracerebral hemorrhage (ICH), who showed delayed development of aphasia, which was demonstrated via follow up diffusion tensor tractography (DTT) to be related to neural degeneration of the arcuate fasciculus (AF). Case presentation A 51-year-old, right-handed male presented with right hemiparesis, which occurred at the onset of a spontaneous ICH in the left corona radiata and basal ganglia. Brain magnetic resonance images showed a hematoma in the left subcortical area at one month after onset and hemosiderin deposits in the left subcortical area at nine years after onset. At four weeks after onset, he exhibited severe aphasia, and Western Aphasia Battery (WAB) testing revealed an aphasia quotient in the 39.6 percentile (%ile). However, his aphasia improved to nearly a normal state, and at three months after onset, his aphasia quotient was in the 90.5 %ile. At approximately eight years after onset, he began to show aphasia, and his aphasia increased slowly with time resulting in a WAB aphasia quotient in the 12.5 %ile at nine years after onset. The integrity of the left AF over the hematoma was preserved on 1-month post-onset DTT. However, the middle portion of the left AF in the middle of the hemosiderin deposits showed discontinuation on 9-year post-onset DTT. The fractional anisotropy value of the left AF was higher on the 9-year post-onset DTT (0.48) than that on the 1-month post-onset DTT (0.35), whereas the mean diffusivity value was lower on the 9-year post-onset DTT (0.10) than that on the 1-month post-onset DTT (0.32). The fiber number of the left AF was decreased to 175 on the 9-year post-onset DTT from 239 on the 1-month post-onset DTT. Conclusions We report on a patient with ICH who showed delayed development of aphasia, which appeared to be related to degeneration of the AF in the dominant hemisphere. Our results suggest that DTT would be useful in ruling out neural degeneration of the AF.

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Tractography of the arcuate fasciculus in healthy right-handed and left-handed multilingual subjects and its relation to language lateralization on functional MRI

Scientific Reports ◽

10.1038/s41598-021-00490-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sandrine Yazbek ◽

Stephanie Hage ◽

Iyad Mallak ◽

Tarek Smayra

Keyword(s):

Functional Mri ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Arcuate Fasciculus ◽

Fiber Volume ◽

Language Lateralization ◽

Highly Educated ◽

Laterality Index ◽

Left Handed ◽

The Right

AbstractFunctional MRI (fMRI) enables evaluation of language cortical organization and plays a central role in surgical planning. Diffusion Tensor Imaging (DTI) or Tractography, allows evaluation of the white matter fibers involved in language. Unlike fMRI, DTI does not rely on the patient’s cooperation. In monolinguals, there is a significant correlation between the lateralization of language on fMRI and on DTI. Our objective is to delineate the arcuate fasciculus (AF) in right- and left-handed trilinguals and determine if the AF laterality on DTI is correlated to language lateralization on fMRI. 15 right and 15 left-handed trilingual volunteers underwent fMRI and DTI. Laterality Index was determined on fMRI (fMRI-LI). Mean Diffusivity, Fractional Anisotropy (FA), Number of Fibers, Fiber Length, Fiber Volume and Laterality Index (DTI-LI) of the AF were calculated on DTI. 28 of the 30 subjects presented a bilateral AF. Most subjects (52%) were found to have a bilateral language lateralization of the AF on DTI. Only 4 subjects had bilateral lateralization of language on fMRI. The right AF demonstrated lower diffusivity than the left AF in the total participants, the right-handed, and the left-handed subjects. FA, Volume and Length of the AF were not significantly different between the two hemispheres. No correlation was found between the DTI-LI of the AF and the fMRI-LI. A prominent role of the right AF and a bilateral structural organization of the AF was present in our multilingual population regardless of their handedness. While in prior studies DTI was able to determine language lateralization in monolingual subjects, this was not possible in trilingual highly educated subjects.

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Abstract TP154: Arcuate Fasciculus Integrity and Outcome of Post-stroke Aphasia: A 6-month Follow-up DTI Study

Stroke ◽

10.1161/str.51.suppl_1.tp154 ◽

2020 ◽

Vol 51 (Suppl_1) ◽

Author(s):

Chorong Bae ◽

Yoonhye Na ◽

Minjae Cho ◽

Yu Mi Hwang ◽

Woo-Suk Tae ◽

...

Keyword(s):

Structural Changes ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Type I ◽

Type Ii ◽

Arcuate Fasciculus ◽

Type Iii ◽

Post Stroke ◽

Fiber Number

Objectives: We evaluated the changes of arcuate fasciculus (AF), an important connecting pathway for language function, using DTI at 1-month and 6-month after stroke and investigated the relationship between structural changes of AF and improvement of post-stroke aphasia. Methods: We collected data from the STroke Outcome Prediction (STOP) database that is prospective data collecting system for functional recovery prediction after stroke based on neuroimaging study. Twenty-six patients with aphasia (PWA) who had first-ever stroke, presence of aphasia evaluated by Western Aphasia Battery (WAB) and no previous neurological or psychiatric diagnosis. The WAB and DTI data within 1 month (initial) and 6 months after (follow-up) stroke onset were used for analysis. And fractional anisotropy (FA), mean diffusivity (MD), fiber number (FN) and differences (Δ) at two time points of these parameters were obtained in bilateral AF in diffusion tensor tractography (DTT). Three types (I: not reconstructed, II: disrupted, discontinued or shallow, III: preserved) of classification according to integrity of AF was also included. Results: DTT parameters of bilateral AF showed statistically significant decrease in FA and increase in MD. Types of AF were changed in 6 patients (23%): 3 patients from type III to type II, 2 patients from type II to type I, and 1 patient from type II to type III. In Pearson’s correlation analysis, significant correlation was observed between 6-mon aphasia quotient (AQ) and parameters of left AF; positive correlation with FA (r=0.707, p<0.001), and negative correlation with MD (r=-.540, p<0.001). However, there was no correlation between 6-mon AQ score and FN of left AF, and all parameters of right AF. In addition, ΔDTT parameters were not correlated with either 6-mon AQ or ΔAQ. Conclusions: The AF changes over time not only in dominant but also in nondominant hemispheres in patients with aphasia after stroke. But amount of changes (Δ) in AF parameters were not associated with language recovery. Acknowledgement: This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (No. 2019R1A2C2003020).

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From Neurosurgical Planning to Histopathological Brain Tumor Characterization: Potentialities of Arcuate Fasciculus Along-Tract Diffusion Tensor Imaging Tractography Measures

Frontiers in Neurology ◽

10.3389/fneur.2021.633209 ◽

2021 ◽

Vol 12 ◽

Author(s):

Matteo Zoli ◽

Lia Talozzi ◽

Matteo Martinoni ◽

David N. Manners ◽

Filippo Badaloni ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

Surgical Planning ◽

Parietal Lobe ◽

Diffusion Tensor ◽

Laplacian Operator ◽

High Angular Resolution ◽

Arcuate Fasciculus ◽

Tumor Patients ◽

Tumor Characterization ◽

Neurosurgical Planning

Background: Tractography has been widely adopted to improve brain gliomas' surgical planning and guide their resection. This study aimed to evaluate state-of-the-art of arcuate fasciculus (AF) tractography for surgical planning and explore the role of along-tract analyses in vivo for characterizing tumor histopathology.Methods: High angular resolution diffusion imaging (HARDI) images were acquired for nine patients with tumors located in or near language areas (age: 41 ± 14 years, mean ± standard deviation; five males) and 32 healthy volunteers (age: 39 ± 16 years; 16 males). Phonemic fluency task fMRI was acquired preoperatively for patients. AF tractography was performed using constrained spherical deconvolution diffusivity modeling and probabilistic fiber tracking. Along-tract analyses were performed, dividing the AF into 15 segments along the length of the tract defined using the Laplacian operator. For each AF segment, diffusion tensor imaging (DTI) measures were compared with those obtained in healthy controls (HCs). The hemispheric laterality index (LI) was calculated from language task fMRI activations in the frontal, parietal, and temporal lobe parcellations. Tumors were grouped into low/high grade (LG/HG).Results: Four tumors were LG gliomas (one dysembryoplastic neuroepithelial tumor and three glioma grade II) and five HG gliomas (two grade III and three grade IV). For LG tumors, gross total removal was achieved in all but one case, for HG in two patients. Tractography identified the AF trajectory in all cases. Four along-tract DTI measures potentially discriminated LG and HG tumor patients (false discovery rate < 0.1): the number of abnormal MD and RD segments, median AD, and MD measures. Both a higher number of abnormal AF segments and a higher AD and MD measures were associated with HG tumor patients. Moreover, correlations (unadjusted p < 0.05) were found between the parietal lobe LI and the DTI measures, which discriminated between LG and HG tumor patients. In particular, a more rightward parietal lobe activation (LI < 0) correlated with a higher number of abnormal MD segments (R = −0.732) and RD segments (R = −0.724).Conclusions: AF tractography allows to detect the course of the tract, favoring the safer-as-possible tumor resection. Our preliminary study shows that along-tract DTI metrics can provide useful information for differentiating LG and HG tumors during pre-surgical tumor characterization.

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Tractography of the Arcuate Fasciculus in Healthy Right-Handed and Left-Handed Multilingual Subjects and Its Relation to Language Lateralization on Functional MRI

10.21203/rs.3.rs-509178/v1 ◽

2021 ◽

Author(s):

Sandrine Yazbek ◽

Stephanie Hage ◽

Iyad Mallak ◽

Tarek Smayra

Keyword(s):

Functional Mri ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Arcuate Fasciculus ◽

Fiber Volume ◽

Language Lateralization ◽

Highly Educated ◽

Laterality Index ◽

Left Handed ◽

The Right

Abstract Purpose Functional MRI (fMRI) enables evaluation of language cortical organization and plays a central role in surgical planning. Diffusion Tensor Imaging (DTI) or Tractography, allows evaluation of the white matter fibers involved in language. Unlike fMRI, DTI does not rely on the patient's cooperation. In monolinguals, there is a good correlation between the lateralization of language on fMRI and on DTI. Our objective is to delineate the arcuate fasciculus (AF) in right- and left-handed trilinguals and determine if the AF laterality on DTI is correlated to language lateralization on fMRI.Methods 15 right and 15 left-handed trilingual volunteers underwent fMRI and DTI. Laterality Index was determined on fMRI (fMRI-LI). Mean Diffusivity, Fractional Anisotropy (FA), Number of Fibers, Fiber Length, Fiber Volume and Laterality Index (DTI-LI) of the AF were calculated on DTI.Results 28 of the 30 subjects presented a bilateral AF. Most subjects (52%) were found to have a bilateral language lateralization of the AF on DTI. Only 4 subjects had bilateral lateralization of language on fMRI. The right AF demonstrated lower diffusivity than the left AF in the total participants, the right-handed, and the left-handed subjects. FA, Volume and Length of the AF were not significantly different between the two hemispheres. No correlation was found between the DTI-LI of the AF and the fMRI-LI.Conclusion A prominent role of the right AF and a bilateral structural organization of the AF was present in our multilingual population regardless of their handedness. While in prior studies DTI was able to determine language lateralization in monolingual subjects, this was not possible in trilingual highly educated subjects.

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Arterial Stiffness Is Associated with White Matter Disruption and Cognitive Impairment: A Community-Based Cohort Study

Journal of Alzheimer s Disease ◽

10.3233/jad-201424 ◽

2021 ◽

Vol 80 (2) ◽

pp. 567-576

Author(s):

Fei Han ◽

Fei-Fei Zhai ◽

Ming-Li Li ◽

Li-Xin Zhou ◽

Jun Ni ◽

...

Keyword(s):

Cognitive Function ◽

White Matter ◽

Arterial Stiffness ◽

Cognitive Decline ◽

Sex Education ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

White Matter Injury ◽

White Matter Integrity ◽

Cross Sectional

Background: Mechanisms through which arterial stiffness impacts cognitive function are crucial for devising better strategies to prevent cognitive decline. Objective: To examine the associations of arterial stiffness with white matter integrity and cognition in community dwellings, and to investigate whether white matter injury was the intermediate of the associations between arterial stiffness and cognition. Methods: This study was a cross-sectional analysis on 952 subjects (aged 55.5±9.1 years) who underwent diffusion tensor imaging and measurement of brachial-ankle pulse wave velocity (baPWV). Both linear regression and tract-based spatial statistics were used to investigate the association between baPWV and white matter integrity. The association between baPWV and global cognitive function, measured as the mini-mental state examination (MMSE) was evaluated. Mediation analysis was performed to assess the influence of white matter integrity on the association of baPWV with MMSE. Results: Increased baPWV was significantly associated with lower mean global fractional anisotropy (β= –0.118, p < 0.001), higher mean diffusivity (β= 0.161, p < 0.001), axial diffusivity (β= 0.160, p < 0.001), and radial diffusivity (β= 0.147, p < 0.001) after adjustment of age, sex, and hypertension, which were measures having a direct effect on arterial stiffness and white matter integrity. After adjustment of age, sex, education, apolipoprotein E ɛ4, cardiovascular risk factors, and brain atrophy, we found an association of increased baPWV with worse performance on MMSE (β= –0.093, p = 0.011). White matter disruption partially mediated the effect of baPWV on MMSE. Conclusion: Arterial stiffness is associated with white matter disruption and cognitive decline. Reduced white matter integrity partially explained the effect of arterial stiffness on cognition.

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Preoperative transcranial magnetic stimulation for picture naming is reliable in mapping segments of the arcuate fasciculus

Brain Communications ◽

10.1093/braincomms/fcaa158 ◽

2020 ◽

Vol 2 (2) ◽

Author(s):

Davide Giampiccolo ◽

Henrietta Howells ◽

Ina Bährend ◽

Heike Schneider ◽

Giovanni Raffa ◽

...

Keyword(s):

Transcranial Magnetic Stimulation ◽

Speech Production ◽

Picture Naming ◽

Magnetic Stimulation ◽

Parietal Lobe ◽

Repetitive Transcranial Magnetic Stimulation ◽

Diffusion Imaging ◽

Arcuate Fasciculus ◽

Preoperative Mapping ◽

Production Errors

Abstract In preoperative planning for neurosurgery, both anatomical (diffusion imaging tractography) and functional tools (MR-navigated transcranial magnetic stimulation) are increasingly used to identify and preserve eloquent language structures specific to individuals. Using these tools in healthy adults shows that speech production errors occur mainly in perisylvian cortical sites that correspond to subject-specific terminations of the major language pathway, the arcuate fasciculus. It is not clear whether this correspondence remains in oncological patients with altered tissue. We studied a heterogeneous cohort of 30 patients (fourteen male, mean age 44), undergoing a first or second surgery for a left hemisphere brain tumour in a language-eloquent region, to test whether speech production errors induced by preoperative transcranial magnetic stimulation had consistent anatomical correspondence to the arcuate fasciculus. We used navigated repetitive transcranial magnetic stimulation during picture naming and recorded different perisylvian sites where transient interference to speech production occurred. Spherical deconvolution diffusion imaging tractography was performed to map the direct fronto-temporal and indirect (fronto-parietal and parieto-temporal) segments of the arcuate fasciculus in each patient. Speech production errors were reported in all patients when stimulating the frontal lobe, and in over 90% of patients in the parietal lobe. Errors were less frequent in the temporal lobe (54%). In all patients, at least one error site corresponded to a termination of the arcuate fasciculus, particularly in the frontal and parietal lobes, despite distorted anatomy due to a lesion and/or previous resection. Our results indicate that there is strong correspondence between terminations of the arcuate fasciculus and speech errors. This indicates that white matter anatomy may be a robust marker for identifying functionally eloquent cortex, particularly in the frontal and parietal lobe. This knowledge may improve targets for preoperative mapping of language in the neurosurgical setting.

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The effect of microvascular obstruction on the myocardial microstructure: a diffusion tensor imaging study

European Heart Journal - Cardiovascular Imaging ◽

10.1093/ehjci/jeaa356.323 ◽

2021 ◽

Vol 22 (Supplement_1) ◽

Author(s):

A Das ◽

K Kelly ◽

M Aldred ◽

I Teh ◽

CK Stoeck ◽

...

Keyword(s):

Microvascular Obstruction ◽

Diffusion Tensor ◽

Spin Echo ◽

Mean Diffusivity ◽

Imaging Study ◽

Free Breathing ◽

Helix Angle ◽

Acquisition Time ◽

Heart Research

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Heart Research UK Background Diffusion tensor cardiac magnetic resonance (DT-CMR) imaging allows for characterising myocardial microstructure in-vivo using mean diffusivity (MD), fractional anisotropy (FA), secondary eigenvector angle (E2A) and helix angle (HA) maps. Following myocardial infarction (MI), alterations in MD, FA and HA proportions have previously been reported. E2A depicts the contractile state of myocardial sheetlets, however the behaviour of E2A in infarct segments, and all DTI markers in areas of microvascular obstruction (MVO) is also not fully understood. Purpose We performed spin echo DTI in patients following ST-elevation MI (STEMI) in order to investigate acute changes in DTI parameters in remote and infarct segments both with and without MVO. Method Twenty STEMI patients (16 men, 4 women, mean age 59) had acute (5 ± 2d) 3T CMR scans. CMR protocol included: second order motion compensated (M012) free-breathing spin echo DTI (3 slices, 18 diffusion directions at b-values 100s/mm2[3], 200s/mm2[3] and 500s/mm2[12], reconstructed resolution was 1.66x1.66x8mm); cine and late gadolinium enhancement (LGE) imaging. Average MD, FA, E2A HA parameters were calculated on a 16 AHA segmental level. HA maps were described by dividing values into left-handed HA (LHM, -90° < HA < -30°), circumferential HA (CM, -30° < HA < 30°), and right-handed HA (RHM, 30° < HA < 90°) and reported as relative proportions. Segments were defined as infarct (positive for LGE) and remote (opposite to the infarct). Results DTI acquisition was successful in all patients (acquisition time 13 ± 5mins). Ten patients had evidence of MVO on LGE images. MD was significantly higher in infarct regions in comparison to remote; MVO-ve infarct segments had significantly higher MD than MVO + ve infarct segments (MD remote= 1.46 ± 0.12x10-3mm2/s, MD MVO + ve = 1.59 ± 0.12x10-3mm2/s, MD MVO-ve = 1.75 ± 0.12x10-3mm2/s, ANOVA p < 0.01). FA was reduced in infarct segments in comparison to remote; MVO-ve infarct segments had significantly lower FA than MVO + ve infarct segments (FAremote= 0.37 ± 0.02, FA MVO + ve = 0.31 ± 0.02 x 10-3mm2/s, MD MVO-ve =0.25 ± 0.02, ANOVA p < 0.01). E2A values were significantly lower in infarct segments compared to remote; MVO + ve infarct segments had significantly lower values than MVO-ve. (E2A remote= 57.4 ± 5.2°, E2A MVO-ve = 46.8 ± 2.5°, E2A MVO + ve = 36.8 ± 3.1°, ANOVA p < 0.001). RHM% (corresponding to subendocardium) was significantly lower in infarct segments compared to remote; MVO + ve infarct segments had significantly lower RHM% than MVO-ve. (RHM remote= 37 ± 3%, RHM RHM MVO-ve= 28 ± 7%, MVO + ve= 8 ± 5%, ANOVA p < 0.001). Conclusion The presence of MVO results in a decrease in MD and increase in FA in comparison to surrounding infarct segments. However, the reduction in E2A and right-handed myocytes on HA in infarct segments is further exacerbated by the presence of MVO. Further study is required to investigate the underlying mechanisms for such alterations in signal intensity. Abstract Figure. A case of transmural septal MI with MVO

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