Cingulum bundle integrity in schizophrenia with auditory verbal hallucinations: A diffusion tensor imaging tractographic study

Background & objectives: Cingulum bundle (CB) is frequently implicated in schizophrenia; however, its role in specific symptoms of schizophrenia such as auditory verbal hallucinations (AVHs) is less explored. Few studies have reported association between reduced integrity of CB and severity of AVH. Using a symptom-based approach, this diffusion tensor imaging (DTI) tractographic study was aimed to assess and compare the integrity of CB in schizophrenia with AVH, schizophrenia without AVH and healthy controls. Methods: A total of 92 right-handed adult individuals (aged 18-50 yr) were recruited across three study groups. Those with Diagnostic and Statistical Manual of Mental Disorders-5 (DSM-5) diagnosis of schizophrenia with AVH (group I; n=30) were compared to those with DSM-5 schizophrenia without lifetime AVH (group II; n=32) and healthy controls (group III; n=30; screened using Mini International Neuropsychiatric Interview version-7.0.0. and negative family history). Clinical assessments (groups I and II) included scale for assessment of positive symptoms, scale for assessment of negative symptoms, clinical global impression-schizophrenia and psychotic symptom rating scale. All participants underwent DTI, and quantitative tract-based measurements of fractional anisotropy (FA) were obtained for images using DTI studio version-3.0. Results: All groups were comparable for age, gender, education and severity of illness. Group I had significantly lower FA values in the cingulate gyrus (CG) part of the left CB compared to groups II and III. No significant difference was found between groups II and III. Interpretation & conclusions: The findings of this study suggest that the disruption in the left CB appears to be specific for AVH-positive schizophrenia. The finding is, however, preliminary subject to replication in future studies. Further investigations are needed to understand its relevance in the context of AVH-positive schizophrenia.

Associations of white matter microstructural abnormalities with clinical symptoms, cognitive impairment and clinical outcomes in the early course of first-episode schizophrenia / 中华行为医学与脑科学杂志

Objective:To investigate the associations of brain white matter integrity deficits, and to explore the association of fractional anisotropy (FA) abnormality with clinical symptoms and cognitive impairments, as well as the prediction effect of the FA alterations on symptoms and cognitive function outcomes in the acute stage of schizophrenia from the whole brain level based on magnetic resonance diffusion tensor imaging (DTI).Methods:From November 2019 to December 2020, thirty-eight patients with first-episode schizophrenia and 38 healthy controls were recruited in this study. Wisconsin card classification test (WCST), digit span test (DST forward/backward), verbal fluency test, Stroop (A/B/C), trail making test (TMT-A/B), as well as positive and negative syndrome scale (PANSS) were utilized to evaluate patients' cognitive function and clinical symptoms both before and after 8 weeks of risperidone monotherapy. T1-weighted images and DTI data of all the subjects were collected . FSL and SPM8 were used to preprocess MRI data and compare the between-group differences of FA. Support vector machine (SVM) analysis was used to evaluate the accuracy of abnormal FA values in differentiating schizophrenic patients from healthy controls. Finally, stepwise multiple regression analysis or generalized linear models were used to explore the associations between white matter integrity and symptoms or cognition.Results:Before treatment, patients' FA values of right medial temporal lobe (mTL), cuneus, anterior cingulate gyrus (ACG) and inferior parietal lobe (IPL) were significantly lower than those in healthy controls ( P<0.01, GRF corrected), and patients' FA values of bilateral middle cingulate gyrus (mCG) were significantly higher than those in the control group ( P<0.01, GRF corrected). SVM analysis showed that four combinations could distinguish the patients from the control with the most accurate rate of 89.47%. Patients' baseline decreased FA values in the right IPL were positively associated with their increased total response time in WCST ( β=0.489, P=0.003, FDR corrected), correct response time in WCST ( β=0.450, P=0.008, FDR corrected), error response time in WCST ( β=0.435, P=0.008, FDR corrected), TMT-B ( β=0.296, P=0.042, FDR corrected), Stroop-C ( β=0.345, P=0.035, FDR corrected), and PANSS-P ( β=0.321, P=0.042, FDR corrected). Reduced FA values in the right mTL in patient group were significantly negatively related to the total time spent on the TMT-A ( β=-0.425, P=0.009, FDR corrected) and TMT-B ( β=-0.325, P=0.026 with FDR correction). Increased FA values in right mCG in patient group demonstrated positive associations with total response time in the WCST ( β=0.585, P=0.002, FDR corrected), correct response time in WCST ( β=0.524, P=0.003, FDR corrected), error response time in WCST ( β=0.536, P=0.003, FDR corrected) and total time consuming in TMT-B ( β=0.484, P=0.004, FDR corrected), as well as negative associations with DST-forward ( β=-0.319, P=0.042, FDR corrected). After treatment, patients' percentage changes in total response time of WCST ( β=0.715, P<0.001, FDR corrected), correct response time of WCST ( β=0.752, P<0.001, FDR corrected), as well as total time-consuming of TMT-A ( β=1.333, P=0.001, FDR corrected) showed positive correlations with baseline increased FA values in the left mCG. Percentage alteration of Stroop-B was negatively correlated with baseline FA values in the right cuneus ( β=-0.745, P=0.015, FDR corrected). Conclusions:The combination of abnormal FA values in multiple brain regions may be potential biomarkers to distinguish schizophrenic patients from healthy volunteers. There was regional dependence in the associations of the impairment of white matter integrity with the cognitive impairment, the severity of psychopathological symptoms as well as the prognosis of patients in the acute stage.

Altered white matter microarchitecture in Parkinson's disease: a voxel-based meta-analysis of diffusion tensor imaging studies / 医学前沿

This study aimed to define the most consistent white matter microarchitecture pattern in Parkinson's disease (PD) reflected by fractional anisotropy (FA), addressing clinical profiles and methodology-related heterogeneity. Web-based publication databases were searched to conduct a meta-analysis of whole-brain diffusion tensor imaging studies comparing PD with healthy controls (HC) using the anisotropic effect size-signed differential mapping. A total of 808 patients with PD and 760 HC coming from 27 databases were finally included. Subgroup analyses were conducted considering heterogeneity with respect to medication status, disease stage, analysis methods, and the number of diffusion directions in acquisition. Compared with HC, patients with PD had decreased FA in the left middle cerebellar peduncle, corpus callosum (CC), left inferior fronto-occipital fasciculus, and right inferior longitudinal fasciculus. Most of the main results remained unchanged in subgroup meta-analyses of medicated patients, early stage patients, voxel-based analysis, and acquisition with 30 diffusion directions. The subgroup meta-analysis of medication-free patients showed FA decrease in the right olfactory cortex. The cerebellum and CC, associated with typical motor impairment, showed the most consistent FA decreases in PD. Medication status, analysis approaches, and the number of diffusion directions have an important impact on the findings, needing careful evaluation in future meta-analyses.

Diffusion tensor imaging in assessment of demyelinating diseases of central nervous system

Background: Conventional MR plays an important role in detection of demyelinating lesions. Involvement of the lesion core, perilesional region and normally appearing white matter (NAWM) cannot be quantified using routine T2/FLAIR sequences. DTI is an important tool in assessment of anisotropy in affected and apparently normal region of brain. 3D Tractography maps are useful in showing white matter fibre loss. Aim was the assessment of white matter damage and neuroaxonal loss using DTI in demyelinating lesionsMethods: Cross sectional observational study including clinically suspected 30 patients of demyelinating disease. Patients were studied in 3Tesla Siemens Skyra MRI scanner with phased array coils. T1w, T2w, FLAIR, DWI, DTI, post contrast T1w images were included and FA, ADC, Tractography maps were generated. ANOVA test and BONFERONI analysis were used.Results: We found mean FA of core lesion was 0.307±0.06, of perilesional region 0.444±0.03 and NAWM 0.567±0.06. The mean ADC value of core of the lesion was 1.24×10-3mm2/sec±0.11×10-3mm2/sec, perilesional region 1.16×10-6mm2/sec ±0.1×10-3mm2/sec and NAWM 1.04×10-3mm2/sec±0.06×10-3mm2/sec.Conclusions: DTI is a useful MR technique that allows quantification of extent of demyelination in the white matter measuring FA and ADC values. The FA values which denote diffusivity and directionality are more reliable marker of demyelination compared to ADC values. DTI Tractography shows white matter tract disruption which may play role in assessing clinical outcome of patients.

Quantitative Predictive Imaging Biomarkers of Lumbar Intervertebral Disc Degeneration

STUDY DESIGN: Observational comparative study. PURPOSE: To compare fractional anisotropy (FA) maps with T2 values of the nucleus pulposus (NP) and annulus fibrosus (AF) of intervertebral discs in healthy volunteers and patients to develop a predictive disc health scale. OVERVIEW OF LITERATURE: T2-weighted magnetic resonance imaging (MRI) is not sensitive to early morphological changes and provides no quantitative biomarker profile for early degeneration. METHODS: We examined 59 healthy controls and 59 patients with back pain by MRI using T2 relaxometry and diffusion tensor imaging (DTI). Each group was divided into three age subgroups: A (50 years, n=21). We obtained FA values for AF and NP and T2 values for NP for each intervertebral disc. Furthermore, we calculated the FA (AF/NP) ratios. RESULTS: We categorized 590 intervertebral discs from 118 participants, 566 of which were analyzed with T2 relaxometry and DTI. The T2 values were as follows: subgroup A, 55.8±4.4 ms; B, 48.5±6.9 ms; C, 45.8±8.7 ms (p120 ms, 90–100 ms, and 70 ms, respectively (p<0.001). Control subgroup A had higher T2 values and AF/NP ratios than subgroups B and C; the AF values were not significantly different. Control subgroup B had higher T2 values and AF/NP ratios than subgroup C but lower FA (NP). CONCLUSIONS: FA maps of the AF/NP ratio and T2 values of NP are potential microstructure biomarkers of normal and degenerating discs and can help detect early degeneration using a predictive disc health score on a continuous scale.

Safety of Autologous Umbilical Cord Blood Therapy for Acquired Sensorineural Hearing Loss in Children

BACKGROUND AND OBJECTIVES: Sensorineural hearing loss (SNHL) in children is associated with neurocognitive morbidity. The cause of SNHL is a loss of hair cells in the organ of Corti. There are currently no reparative treatments for SNHL. Numerous studies suggest that cord blood mononuclear cells (human umbilical cord blood, hUCB) allow at least partial restoration of SNHL by enabling repair of a damaged organ of Corti. Our objective is to determine if hUCB is a safe treatment for moderate to severe acquired SNHL in children. SUBJECTS AND METHODS: Eleven children aged 6 months to 6 years with moderate to severe acquired SNHL were treated with intravenous autologous hUCB. The cell dose ranged from 8 to 30 million cells/kg body weight. Safety was assessed by measuring systemic hemodynamics during hUCB infusion. Infusion-related toxicity was evaluated by measuring neurologic, hepatic, renal and pulmonary function before and after infusion. Auditory function, auditory verbal language assessments and MRI with diffusion tensor imaging (DTI) were obtained before and after treatment. RESULTS: All patients survived, and there were no adverse events. No infusionrelated changes in hemodynamics occurred. No infusion-related toxicity was recorded. Five subjects experienced a reduction in auditory brainstem response (ABR) thresholds. Four of those 5 subjects also experienced an improvement in cochlear nerve latencies. Comparison of MRI with DTI sequences obtained before and after treatment revealed increased fractional anisotropy in the primary auditory cortex in three of five subjects with reduced ABR thresholds. Statistically significant (p < 0.05) reductions in ABR thresholds were identified. CONCLUSIONS: TIntravenous hUCB is feasible and safe in children with SNHL.

Application of magnetic resonance diffusion tensor imaging in rat C 6 glioma grading / 重庆医学

Objective To explore the application value of fractional anisotropy(FA)values of magnetic resonance diffusion tensor imaging(DTI)parameters in rat rat glioma grading.Methods Sixty-seven female Wistar rats were divided into the experi-mental group(n=57)and control group(n=10)according to the random number table method.All the surviving rats were exam-ined by 3.0T DTI at 1-2 weeks(22 cases)and 3-4 weeks(35 cases)after inoculation,and the FA values of the tumor were ob-tained and compared with the pathological results.Results Among 57 tumor-loading rats,there were 18 low-grade gliomas and 39 high-grade gliomas.DTI showed that the FA value of high-grade gliomas was higher than that of the low-grade glioma,the differ-ence was statistically significant[(0.167 ± 0.035)vs.(0.147 ± 0.015),t=2.34,P<0.05].Conclusion The FA value of DTI pa-rameters can provide accurate,reliable and noninvasive imaging information for preoperative glioma grading.

A quantitative study on evaluation of child diffuse axonal injury severity by using MR diffusion tensor imaging / 重庆医学

Objective To compare the value of fractional anisotropy(FA)of MR diffusion tensor imaging(DTI) and Glasgow coma scale(GCS) at admission for judging the injury severity and prognosis of diffuse axonal injury (DAI). Methods Thirty-four patients with DAI adopted the GCS score to evaluate the conscious disturbance levels at admission and conducted the DTI examination within 2 weeks. Twenty-three individuals undergoing healthy physical examination conducted the DTI examination. The FA values of visuality lesion area in various sites,healthy side symmetric site and cerebral midline site were measured. The reduction degree of mean FA value at midline site and visuality lesions were measured. The correlation between GCS score,mean FA value reduction degree in visuality lesions and mean FA value at cerebral midline site with consciousness disorder time and recovery degree in half a year after injury was analyzed. Results The reduction degree of mean FA value at cerebral midline site was significantly correlated with consciousness disorder time and recovery degree in half a year after injury(r= 0. 519,P=0. 002; r= 0. 669, P=0. 000) ;the mean FA value reduction degree in visuality lesions and GCS score had low or weak correlation with consciousness dis order time and recovery degree in half a year after injury(r=0. 285,P=0. 103;r=0. 487,P=0. 003;r= -0. 241,P=0. 169;r=-0. 229,P=0. 192). The correlation between mean FA reduction degree in cerebral midline site and mean FA value reduction degree in visuality lesions with the recovery degree in a half years after injury was higher than that in GCS score. Conclusion DTI is a sensitive sequence for diagnosing DAI and has much more value for judging the injury degree and prognosis than the GCS score generally adopted by clinic.

Diffusion tensor imaging to assess recovery of white matter injury in periventricular leucomalacia with cerebral palsy after surgery / 实用放射学杂志

Objective To discuss the value of DTI on recovery of white matter injury in periventricular leucomalacia (PVL) with cerebral palsy after surgery.Methods 15 childrens suffered from PVL and 15 age-matched normal controls with normal MRI findings and no neurological abnormalities were recruited in this study.Conventional plain MRI scans and DTI sequence of brain were preformed in all subjects.FA maps of eight selected regions,which included the corpus callosum genu,splenium of corpus callosum,bilateral anterior limb of internal capsule,bilateral posterior limb of internal capsule,bilateral optic radiation,bilateral cerebral pedunculusand superior longitudinal fasciculus were compared between two groups.Results Significant differences of FA values were observed among the three group before and after the treatment and control groups(P＜0.05).FA value of the caudate nucleus and lenticular nucleus among three group was not statistically significant difference.Further pairwise comparison,FA values of the posterior limb of internal capsul,genu of corpus callosum and splenium of corpus callosum in three groups showed statistically significant differences,there was no statistically significant difference for FA value of the genu of capsulae internae,cerebral peduncle and pons among the three group.Compared to the contralateral normal areas,FA value of the genu of capsulae internae,cerebral peduncle and pons showed statistically significant differences (P＜0.05).Conclusion Quantitative DTI may show subtle changes in the structure of white matter,which has a certain reference value of FA values of white matter in periventricular leucomalacia with cerebral palsy after surgery,and help clinicians further reasonable treatment.

DTI analysis on white matter changes in children with ametropic amblyopia / 眼科新进展

Objective To evaluate white matter nerve fiber changes of children with binocular ametropic amblyopia by applying the technology of diffusion tensor imaging and the whole brain analysis method of deterministic tractography,and analyze its correlation with visual acuity.Methods Fourteen binocular ametropic amblyopia children was collected from the Second Xiangya Hospital of Central South University as study subject of experimental group,14 cases of normal sight children as the control group.All children were scanned by MRI system,conventional MRI examination,3DTlWI scan were made,then echo-planar sequence scanning was used to obtain diffusion tensor imaging.Quantitative analysis was made to all diffusion tensor imaging using deterministic tractography.Using the experimental group tracts with statistic changes of FA value,volume and tract count as the region of interest(ROI),the correlation analysis with vision for each ROI was performed.Results Isoametropic amblyopia children demonstrated low FA values in the right ventral and dorsal pathway,right optic radiation and corpus callosum compared to control group.There was low volume of fibers in the bilateral ventral and dorsal pathway,the left optic radiation and body of corpus callosum compared to control group.The tract count of right dorsal pathway had reduced compared to control group.Among FA value,tract count and volume,FA value had the maximum regression coefficient with visual acuity,the regression coefficient of tract count and volume was small.The relative correlation coefficient of FA value at right optic radiation,right ventral pathway and body of corpus callosum with vision acuity were 0.486,0.534 and 0.456,respectively,the right ventral pathway had the maximum correlation with visual acuity.Conclusion Isoametropic amblyopia patients shows abnormal structure on bilateral optic radiation,bilateral ventral and dorsal pathway and body of corpus cailosum,these may cause the capability loss of object recognition and spatial position recognition.The FA value of right ventral pathway has the maximum influence on visual acuity.

The relationship between fractional anisotropy value and tumor microarchitecture in late-stage rat glioma

Objective To explore the magnetic resonance diffusion tensor imaging (MR-DTI) features of in the late stage of Wistar rat C6 brain glioma, and the relationship between fractional anisotropy value and tumor microarchitecture. Methods The concentration of more than 1.0 × 10

Application of diffusion tensor imaging FA value and ADC value in glioma grading:A Meta-analysis / 吉林大学学报(医学版)

Objective:To clarify the significance of the fractional anisotropy(FA) value and apparent diffusion coefficient(ADC) value of diffusion tensor imaging(DTI) applied in the glioma grading with Meta-analysis, and to provide a reference for selecting the treatment program and judging the prognosis of glioma.Methods:Computer search was performed in PubMed database, EMBASE database,CBM, CNKI, Wanfang database, and VIP database.The relevant neurosurgery magazines and neuroimaging magazines, the proceedings of academic meeting were retrieved by hand and the references of related reviews were retrospectively retrieved.Then the case-series studies according to inclusion and exclusion criteria were screened,and the qualities of included studies were evaluated.Meta-analysis was carried out by Review Manager 5.2 software.Results:Nine studies were included.The FA value of low-grade glioma(LGG) in tumor centre was lower than that of high-grade glioma(HGG) (χ2=11.94,df=8,P=0.15;I2=33%,Z=2.78,P=0.005;WMDFA=-0.02,95%CI:-0.03--0.01),and the ADC value of LGG in tumor centre was higher than that of HGG (χ2=5.26,df=4,P=0.26;I2=24%,Z=2.19,P=0.03;WMDADC=0.15,95%CI:0.02-0.28).Conclusion:When the FA value in tumor centre of the glioma is increasd,the ADC value is decreased,and the grade of glioma is increasd.The FA value and ADC value of DTI can help determine the grade of gliomas.

The relationship between fractional anisotropy value and tumor microarchitecture in late-stage rat glioma

OBJECTIVE@#To explore the magnetic resonance diffusion tensor imaging (MR-DTI) features of in the late stage of Wistar rat C6 brain glioma, and the relationship between fractional anisotropy value and tumor microarchitecture.@*METHODS@#The concentration of more than 1.0 × 10/10 μL glioma cells and complete medium were injected stereotactically into the right caudate nucleus of the experimental group (n = 35) and control group (n = 10), respectively. Conventional MRI, DTI, and enhanced T1WI scans were Performed using the GE Signa HD × 3.0T MRI scanner about 3-4 weeks after implantation for the rats. Postprocessing was done using the DTI specific software Function Tool to gain FA image. Many ROIs were drawn avoiding hemorrhage, necrosis areas in tumor parenchyma, the value of FA was recorded. Each surviving rat brain was examined histologically using HE and immunohistochemical staining for VEGF and CD34. Pearson correlation analysis was used to determine the relationships between FA values and VEGF, MVD, cell density, respectively.@*RESULTS@#A total of 35 tumor-bearing rats were confirmed the tumor formation by the subsequent MRI and pathological examination. The mean FA values of the tumor and the contralateral brain tissue were 0.17 ± 0.03 and 0.31 ± 0.05 respectively, and the difference was statistically significant (t = 12.80, P  0.05). FA value in the late stage of Wistar rat C6 brain glioma has significant positive correlation to VEGF, MVD, cell density. The correlation coefficients between FA and VEGF, MVD, and cell density were 0.67, 0.65 and 0.71 (P < 0.05), respectively.@*CONCLUSIONS@#The FA value of rat glioma tumor in the late stage can preoperatively provide an accurate, reliable and noninvasive imaging monitoring method to evaluate the microstructure of glioma (cell density, the extent of angiogenesis, fiber bundle integrity and tumor cell infiltration and so on), predict the biological behavior of the tumor and make out surgical plan.

Diffusion tensor imaging study of white matter fiber in patients with schizophrenia episode in early adulthood / 新乡医学院学报

Objective To explore the structure changes of white matter of the patients with schizophrenia episode in early adulthood by diffusion tensor imaging(DTI) and in order to provide a structural neuroimaging basis for understanding the pathology of schizophrenia.Methods Twenty-six patients with schizophrenia episode in early adulthood in the Second Affiliated Hospital of Xinxiang Medical University from July 2012 to March 2014 were selected as study group and twenty-eight healthy subjects whose age,sex,education were matched with study group were selected as control group.All subjects received structural magnetic resonance imaging and DTI scans.The fractional anisotropy (FA) and the mean diffusivity (MD) of the white matter of the same encephalic region were compared between the two groups by voxel-based analyses.Results The FA values of the right anterior cingulate gyrusthe,genu of corpus callosum,the right limb of internal capsule,the bilateral external capsule,the bilateral posterior of coronal radiate,the right anterior coronal radiate of patients in the study group were significantly lower than those in the control group (P ＜ 0.05).The MD values of the bilateral limbs of internal capsule,the right cingulate gyrus,left superior longitudinal tract,corpus callosum and right anterior coronal radiate of patients in the study group were significantly higher than those in the control group (P ＜ 0.05).Conclusion Schizophrenia patients who episode in early adulthood exist widespread microstructural damage of white matter.These changes may be related to the pathological change of schizophrenia.

Assessment of the diagnostic value of diffusion tensor imaging in patients with spinal cord compression: a meta-analysis

We investigated the diagnostic value of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of magnetic resonance diffusion tensor imaging (DTI) in patients with spinal cord compression (SCC) using a meta-analysis framework. Multiple scientific literature databases were exhaustively searched to identify articles relevant to this study. Mean values and standardized mean differences (SMDs) were calculated for the ADC and FA in normal and diseased tissues. The STATA version 12.0 software was used for statistical analysis. Of the 41 articles initially retrieved through database searches, 11 case-control studies were eligible for the meta-analysis and contained a combined total of 645 human subjects (394 patients with SCC and 251 healthy controls). All 11 studies reported data on FA, and 9 contained data related to the ADC. The combined SMDs of the ADC and FA showed that the ADC was significantly higher and the FA was lower in patients with SCC than in healthy controls. Subgroup analysis based on the b value showed higher ADCs in patients with SCC than in healthy controls at b values of both ≤500 and >500 s/mm2. In summary, the main findings of this meta-analysis revealed an increased ADC and decreased FA in patients with SCC, indicating that DTI is an important diagnostic imaging tool to assess patients suspected to have SCC.

Diffusion tensor imaging for evaluating white matter fiber tracts in patients with mild traumatic brain injury / 实用放射学杂志

Objective To study the changes of white matter fiber tracts in mild traumatic brain injury(mTBI)patients by using DTI technique on 3.0T MR system,and evaluate the clinical diagnostic value of DTI.Methods Thirty mTBI and 30 matched health-y controls underwent conventional CT,MRI and DTI examinations.FA values and ADC values in the genu of the corpus callosum, the splenium of the corpus callosum,bilateral internal capsule,the cingulum bundle,the bilateral superior longitudinal fasciculus and the inferior longitudinal fasciculus of mTBI were measured in mTBI patients and controls at acute phase,subacute phase,5 weeks and 3 months post-trauma.The temporal changes of MRI data were observed.Results The FA values in the part of the white mat-ter fiber tracts reduced in the acute and subacute phase in mTBI patients (all P 0.05),but de-creased at 5 weeks-3 months post-trauma phase,though there was no significantly difference(all P >0.05).ADC values significantly decreased in the acute and subacute phase in mTBI patients,while they recovered thereafter (all P >0.05).Conclusion The sensi-tivity of DTI in detecting the lesions of mild traumatic brain damage is high,and it can display the damage of white matter.DTI could play an important role in the diagnosis of mTBI.

Evaluation for Injury in Optic Radiation after Ischemic Stroke with Diffusion Tensor Imaging / 中国康复理论与实践

Objective To evaluate the injury of optic radiation after ischemic stroke with diffusion tensor imaging (DTI). Methods From September, 2014 to September, 2015, twenty-one ischemic stroke inpatients with visual field defects were tested with DTI, and measured the fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of both sides in different time. The correlation of FA and ADC to visual field mean defect (MD) in the same time was analyzed. Results The FA of affected sides was lower than that of healthy sides twenty-four hours (t=2.38, P<0.05), one week (t=15.60, P<0.01) and four weeks (t=19.13, P<0.01) after stroke, and the ADC was also lower twenty-four hours (t=10.13, P<0.01) and one week (t=6.06, P<0.01) after stroke. The FA correlated with MD one (r=0.581, P<0.01) and four weeks (r=0.703, P<0.01) after stroke, and the ADC correlated with MD twenty-four hours after stroke (r=0.519, P<0.05). The FA of one (r=0.525, P<0.05) and four weeks (r=0.762, P<0.01) after stroke correlated with MD six months after stroke. Conclusion DTI can be used to evaluate the injury of optic radiation after ischemic stroke.

Value of diffusion tensor imaging and T2 mapping to assess lumbar intervertebral disc degeneration / 实用放射学杂志

Objective To investigate the value of ADC and FA of diffusion tensor imaging(DTI)and T2 value of T2 mapping for assessing lumbar intervertebral disc degeneration.Methods 12 cases of healthy volunteers(8 males and 4 females),28 cases of patients with chronic low back pain(15 males and 13 females,19-70 years old)were performed lumbar spine MRI,DTI and T2 mapping to obtain ADC,FA and T2 value.Intervertebral discs were classified according to the Pfirrmann grading.The correlations of different degeneration grade with ADC,FA and T2 value were analyzed.The diagnostic value of ADC,FA and T2 values of lumbar intervertebral disc degeneration were compared. Results Both ADC value and T2 value were significantly negative correlated with lumbar intervertebral disc degeneratic Pfirrminn grading(r=-0.779,r=-0.708,P<0.001).FA value were positively correlated with Pfirrminn grading(r=0.474,P<0.001), the correlation was not closely.Conclusion DTI and T2 mapping can be effectively used to quantitatively evaluate the degeneration degree of lumbar intervertebral disc,the diagnostic value of ADC was the highest,followed by T2 ,and FA was the worst.

Discrimination between Lumbar Intraspinal Stenosis and Foraminal Stenosis using Diffusion Tensor Imaging Parameters: Preliminary Results

STUDY DESIGN: Retrospective observational study. PURPOSE: To examine fractional anisotropy (FA) values and apparent diffusion coefficient (ADC) values of damaged nerves to discriminate between lumbar intraspinal stenosis (IS) and foraminal stenosis (FS) using diffusion tensor imaging (DTI) OVERVIEW OF LITERATURE: It is important in the selection of surgical procedure to discriminate between lumbar IS and FS, but such discrimination is difficult. METHODS: There were 9 cases of IS, 7 cases of FS, and 5 healthy controls. The regions of interest were established in the lumbar intraspinal zone (Iz), nerve root (N), and extraforaminal zone (Ez). The FA and ADC values were measured on the affected and unaffected sides of the nerves. The FA ratio and the ADC ratio were calculated as the affected side/unaffected side ×100 (%). RESULTS: In the Ez, the FA value was significantly lower in FS than in IS (p<0.01). FA ratio was significantly lower in FS than in IS for the Ez (p<0.01). In the Iz, the ADC value was significantly higher in IS than FS (p<0.01). ADC ratio was significantly higher in FS than in IS for the N and Ez (p<0.05). For the Ez, receiver operating characteristic analysis of parameters revealed that the FA values showed a higher accuracy for the diagnosis of FS than the ADC values, and the FA value cut-off value was 0.42 (sensitivity: 85.7%, false positive: 11.1%) and the FA ratio cut-off value was 83.9% (sensitivity: 85.7%, false positive: 22.2%). CONCLUSIONS: The low FA value in the extraforaminal zone suggests the presence of foraminal stenosis. When the FA value and FA ratio cut-off value were established as 0.42 and 83.9%, respectively, the accuracy was high for the diagnosis of foraminal stenosis. It may be possible to use DTI parameters to help in the discrimination between IS and FS.

Diagnosis of Lumbar Foraminal Stenosis using Diffusion Tensor Imaging

Diagnosis of lumbar foraminal stenosis remains difficult. Here, we report on a case in which bilateral lumbar foraminal stenosis was difficult to diagnose, and in which diffusion tensor imaging (DTI) was useful. The patient was a 52-year-old woman with low back pain and pain in both legs that was dominant on the right. Right lumbosacral nerve compression due to a massive uterine myoma was apparent, but the leg pain continued after a myomectomy was performed. No abnormalities were observed during nerve conduction studies. Computed tomography and magnetic resonance imaging indicated bilateral L5 lumbar foraminal stenosis. DTI imaging was done. The extraforaminal values were decreased and tractography was interrupted in the foraminal region. Bilateral L5 vertebral foraminal stenosis was treated by transforaminal lumbar interbody fusion and the pain in both legs disappeared. The case indicates the value of DTI for diagnosing vertebral foraminal stenosis.