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OBJECTIVE@#To investigate whether meranzin hydrate (MH) can alleviate depression-like behavior and hypomotility similar to Chaihu Shugan Powder (CSP), and further explore the potential common mechanisms.@*METHODS@#Totally 120 Spraque-Dawley rats were randomly divided into 5-8 groups including sham, vehicle, fluoxetine (20 mg/kg), mosapride (10 mg/kg), CSP (30 g/kg), MH (9.18 mg/kg), [D-Lys3]-GHRP-6 (Dlys, 0.5 mg/kg), and MH+Dlys groups by a random number table, 8 rats in each group. And 32 mice were randomly divided into wild-type, MH (18 mg/kg), growth hormone secretagogue receptor-knockout (GHSR-KO), and GHSR+MH groups, 8 mice in each group. The forced swimming test (FST), open field test (OFT), tail suspension test (TST), gastric emptying (GE) test, and intestinal transit (IT) test were used to assess antidepressant and prokinetic (AP) effects after drug single administration for 30 min with absorbable identification in rats and mice, respectively. The protein expression levels of brain-derived neurotrophic factor (BDNF) and phosphorylated mammalian target of rapamycin (p-mTOR) in the hippocampus of rats were evaluated by Western blot. The differences in functional brain changes were determined via 7.0 T functional magnetic resonance imaging-blood oxygen level-dependent (fMRI-BOLD).@*RESULTS@#MH treatment improved depression-like behavior (FST, OFT) and hypomotility (GE, IT) in the acute forced swimming (FS) rats (all P<0.05), and the effects are similar to the parent formula CSP. The ghrelin antagonist [D-Lys3]-GHRP-6 inhibited the effect of MH on FST and GE (P<0.05). Similarly, MH treatment also alleviated depression-like behavior (FST, TST) in the wild-type mice, however, no effects were found in the GHSR KO mice. Additionally, administration of MH significantly stimulated BDNF and p-mTOR protein expressions in the hippocampus (both P<0.01), which were also prevented by [D-Lys3]-GHRP-6 (P<0.01). Besides, 3 main BOLD foci following acute FS rats implicated activity in hippocampus-thalamus-basal ganglia (HTB) circuits. The [D-Lys3]-GHRP-6 synchronously inhibited BOLD HTB foci. As expected, prokinetic mosapride only had effects on the thalamus and basal ganglia, but not on the hippocampus. Within the HTB, the hippocampus is implicated in depression and FD.@*CONCLUSIONS@#MH accounts for part of AP effects of parent formula CSP in acute FS rats, mainly via ghrelin-related shared regulation coupled to BOLD signals in brain areas. This novel functionally connection of HTB following acute stress, treatment, and regulation highlights anti-depression unified theory.
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Rats , Mice , Animals , Brain-Derived Neurotrophic Factor/metabolism , Ghrelin/metabolism , Antidepressive Agents/therapeutic use , Hippocampus , Stress, Psychological , Mammals/metabolismABSTRACT
Objectives:To explore the value of blood oxygen level-dependent (BOLD) MRI in evaluating the changes of placental oxygenation during maternal hyperoxia.Methods:From October 2017 to March 2020, 22 singleton pregnant women with normal placenta showed by ultrasound were prospectively included in Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology. Pregnant women wore oxygen mask before examination, and then underwent BOLD MRI examination for 10 min. The pregnant women inhaled air in the first 3 min and continuously inhaled oxygen with purity greater than 90% in the next 7 min (flow rate 12 L/min). The average value of BOLD signal of the whole placenta, fetal side of placenta, maternal side of placenta and maternal kidney were measured and calculated in the first 3 min as before oxygen and the last 3 min of the end of oxygen inhalation as after oxygen. The ΔBOLD was calculated which was the change value of BOLD signal before and after oxygen inhalation. The BOLD values of placenta and maternal kidney before and after oxygen inhalation were compared by using paired t-test. The ΔBOLD of the whole placenta, the fetal side of the placenta and the maternal side of the placenta were compared by using one-way ANOVA, and the LSD method was used for pairwise comparison between groups. Results:There were significant differences in BOLD values of the whole placenta, fetal side of placenta and maternal side of placenta before and after oxygen inhalation ( t=-4.62, P<0.001; t=-4.73, P<0.001; t=-3.57, P=0.002). There was no significant difference in BOLD value of maternal kidney before and after oxygen inhalation ( t=0.35, P=0.740). The ΔBOLD values of the whole placenta, fetal side of placenta and maternal side of placenta were (12.8±2.2)%, (15.1±2.7)% and (6.4±1.3)% respectively. The overall difference was statistically significant ( F=4.49, P=0.015). The results of pairwise comparison showed that there was no significant difference in ΔBOLD between the whole placenta and the fetal side of the placenta ( P=0.450). There were significant differences in ΔBOLD between whole placenta and maternal side of placenta ( P=0.037) and between fetal side and maternal side of placenta ( P=0.005). Conclusion:Under the condition of maternal hyperoxia, the BOLD signal of placenta increased significantly, and the change of fetal side of placenta was more obvious than that of maternal side. BOLD-MRI has the potential of semi-quantitative and real-time evaluation of placental oxygenation.
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Myopia is a major problem of public health in China, and even in the world, and slowing down the progress of myopia has become a hot issue of concern. However, the effects of the current therapeutic and interventional modalities to myopia, including optical lenses, chemical drugs, and laser surgery, the effect of treatment and intervention is not very satisfactory, and these modalities may incur some side effects. This situation suggests that the pathogenic and regulatory mechanisms of myopia remain elusive, and the myopia treatments lack the accurate and effective targets to the etiology. A complete visual experience depends on the entire visual pathway from the retina to the visual cortex, in which any structural and functional defect can lead to visual abnormalities. In recent years, with the advances in the infrared spectroscopy and the magnetic resonance imaging technology, more and more evidence has shown that the progression of myopia is related to the visual cortex. Improving the functional connectivity and blood prefusion between different regions of the visual cortex may impede myopia profession. In-depth understanding of the interaction between myopia and the visual cortex is helpful to search for accurate and effective myopia treatment targets and novel intervention strategies.
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Objective:To investigate the clinical application value of blood oxygen level dependent functional magnetic resonance imaging (BOLD-fMRI) to the protection of language function in patients with unilateral frontal and temporal lobes glioma receiving postoperative intensity modulation radiation therapy (IMRT).Methods:A total of 27 patients with unilateral frontal and temporal lobe gliomas were treated with postoperative radiotherapy. The planning CT and BOLD-fMRI were performed before radiotherapy, and the language functional areas were delineated based on the fused images of 3D T1 and CT. IMRT technology was used to develop radiotherapy plans with and without language function area protection, naming conventional and protective radiotherapy plans respectively. The maximum radiation dose ( Dmax), average radiation dose ( Dmean), target conformal (CI) and dose uniformity (HI) of PTV of the two plans were compared and analyzed to ensure that the protective radiotherapy plan could meet the radiotherapy standard. Then, the Dmax and Dmean of the language function area were compared and analyzed to evaluate whether the Dmax and Dmean of the language function area were decreased in the protective radiotherapy plan. Results:There were no significant differences in CI, HI, Dmax and Dmean of PTV between the conventional radiotherapy plan and protective radiotherapy plan ( P>0.05). There were statistically significant differences in Dmax and Dmean of Wernicke′s and Broca′s (healthy side and affected side) between the conventional radiotherapy plan and protective radiotherapy plan ( t=3.073-12.707, P<0.05). Dmax and Dmean of Wernicke′s and Broca′s (healthy side and affected side) were decreased in the protective radiotherapy plan compared with the conventional radiotherapy plan, and the decrease was significant in the healthy side. Conclusions:BOLD-fMRI combined with IMRT can not only guarantee the target dose of patients with glioma receiving postoperative radiotherapy, but also reduces the radiation dose to the language function area. Chinese reading task and paragraph comprehension task are the stimulation mode of language function in patients after brain tumor surgery. These tasks are simple and the effect is accurate.
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Objective: To evaluate renal tissue oxygenation level and its correlation with blood glucose level after hypoglycemic therapy in diabetic patients using BOLD-MRI. Methods Renal BOLD-MRI scans were performed on 23 patients with type 2 diabetes (diabetic group) before and after hypoglycemic therapy and 23 normal controls (control group). R2* values of renal cortex and medulla were measured and statistically analyzed. Results R2* value of renal cortex in diabetic group and control group were lower than that of renal medulla (all P<0.001). R2* value of renal medulla in diabetic group before hypoglycemia was higher than that after hypoglycemia and in control group (both P=0.001), and there was no significant difference of R2* value of renal medulla between diabetic group after hypoglycemia and control group (P=0.941). There was no significant difference in renal cortical R2* value among diabetic group before and after hypoglycemia and control group (P=0.572). R2* value of renal medulla was positively correlated with blood glucose level (r=0.365, P=0.002), while of renal cortex had no correlation with blood glucose level (r=-0.014, P=0.908). Conclusion: Hypoglycemic treatment can help to improve oxygenation of renal medulla in diabetic patients. BOLD-MRI can be used to evaluate changes of renal oxygen content before and after hypoglycemic treatment.
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OBJECTIVE: To explore the correlation between blood oxygen level dependent functional magnetic resonance imaging (BOLD-fMRI) signal and neurotransmitter γ-aminobutyric acid (GABA) concentration in the prefrontal cortex area after acupuncture or Von Frey filament stimulation (epidermal stimulation) at the right Hegu (LI4). METHODS: A total of 76 healthy volunteers (23 men and 53 women, 24.5±1.4 years in age) were recruited in the pre-sent study. Each volunteer received two sessions of fMRI magnetic resonance scanning (MRS) examinations, with an interval of one week between two sessions. The MRI scan sequences included pre-task MRS, resting state BOLD and task MRS, BOLD. A region of Interest (ROI) of 35 mm×30 mm×25 mm was located at the bilateral medial prefrontal cortex areas. In the two sessions of examinations, the right LI4 point was stimulated by manual acupuncture or Von Frey filament-pressing. The tasks were designed as the block design. Each block contained 3 intermittent acupoint stimulations, lasting 30 s in each stimulation and with two minutes' pause between two stimulations. The MRS data were processed by using Linear Combination (LC) Model software (for assessing GABA content), and the BOLD data of fMRI was analyzed by using SPM12 software (comparison within each group), REST1.8 (comparison between two groups), separately. RESULTS: Extensive deactivations were induced by both stimulations, mainly involving the midline regions as the medial prefrontal lobe, and limbic lobe. The deactivation effect of manual acupuncture stimulation was more extensive and intensive than that of Von Frey filament stimulation, especially in the medial prefrontal lobe. Data from 66 volunteers (after exclusion of 10 participants due to bigger standard deviation of GABA/Glx) showed no marked correlation between the GABA concentration and BOLD activation in the anterior cingulate cortex area in both groups(manual acupuncture stimulation group: r=－0.07, －0.08, 0.04; P=0.57, 0.88, 0.74; Von Frey filament epidermal stimulation group: r=－0.10, －0.09, －0.01; P=0.43, 0.46, 0.96). CONCLUSION: Acupuncture of LI4 elicits a stronger and broader negative activation effect in the limbic-paralimbic-neocortical network including the medial prefrontal cortex in comparison with Von Frey filament stimulation, but no apparent correlation was found between the GABA concentration and BOLD activation in the anterior cingulate cortex after manual acupuncture and Von Frey stimulation.
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Objective To investigate the value of blood oxygen level-dependent (BOLD) and arterial spin labeling (ASL) MRI in the early diagnosis of renal allograft dysfunction. Methods A total of 53 patients with allograft kidney transplantation from December 2014 to April 2017 in Tianjin First Center Hospital were prospectively collected. In all cases, the serum creatinine value was detected, and the estimated glomerular filtration rate (eGFR) was calculated. All patients were divided into three groups according to the eGFR. There were three groups;continuous renal transplant function group (group A, 19 cases), short term allograft dysfunction group (group B, 17 cases), and continuous renal function damage group (group C, 17 cases). Fifty-three patients were examined by BOLD and ASL MRI at 10 to 14 days after operation. Twenty one patients were reviewed by BOLD and ASL MRI at 10 to 13 weeks after operation (A, B and C group were 7, 6, 8 cases). The values of renal cortex R2* (R2*=1/T2*), renal medullary R2* and renal cortical renal blood flow (RBF) were measured in each group. One-way analysis of variance (ANOVA) was used to compare the differences of eGFR and BOLD, ASL index (renal cortex R2*, renal medulla R2*, renal cortex RBF value) after the first post renal transplant among the 3 groups. Correlations between BOLD and ASL index with eGFR index in the first post renal transplant were assessed by using Pearson correlation analysis. The efficacy of BOLD and ASL in the differential diagnosis of continuous renal transplant function group and short term allograft dysfunction group by the receiver operating characteristic (ROC). Paired samples t test was used to compare the differences of eGFR, BOLD and ASL indexes for the baseline and follow-up. Results The differences of eGFR, cortical R2*value, medullary R2*value and cortical RBF value were statistically significant between the 3 groups (P<0.05). The transplanted kidney medullary R2* value and cortical RBF value were positively correlated with eGFR (r values were 0.553, 0.687; P<0.01). There was no correlation between transplanted kidney renal cortex R2*value and eGFR value (P>0.05). The area under ROC was 0.776 for the renal medullary R2*in the diagnosis of continuous renal transplant function group and the short term allograft dysfunction group;with the threshold of 24.5, the sensitivity of diagnosis of renal allograft short term allograft dysfunction was 58.8%, specificity was 84.2%;the area under ROC for renal cortex RBF was 0.881, with the threshold of less than 277 ml·100 g-1·min-1, the sensitivity was 70.6%, specificity was 89.4%. During follow-up, eGFR, cortical R2*and medullary R2*in group A remained stable, while the renal cortex RBF value went slightly higher, and the differences were statistically significant ( P<0.05). The cortical R2* values in group B remained stable, eGFR, renal medulla R2* and renal cortex RBF decreased, and the differences were statistically significant (P<0.05). The values of eGFR and R2*in group C remained stable, while the renal medullary R2* value and cortex R2* value increased slightly, and the differences were statistically significant (P<0.05). Conclusions This study shows that BOLD and ASL MRI can longitudinally monitor the functional status of the transplanted kidney and detect the abnormality of renal allograft function early. CRBF value shows high diagnostic value.
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Purpose To discuss the value of longitudinal assessment of the remaining kidney of the donor and kidney blood oxygen level changes after receiving kidney transplantation by applying blood oxygen level-dependent (BOLD) MRI. Materials and Methods Sixty patients underwent parental kidney transplantation from Jul. 2015 to Feb. 2017 in Tianjin First Center Hospital were prospectively collected, including 30 healthy kidney transplant donors and 30 recipients corresponding to them. The donors received renal BOLD examination 3 days before and 2 weeks after unilateral nephrectomy. Recipients received renal BOLD examination 2 weeks after kidney transplantation, of which, 15 pairs of patients underwent parental kidney transplantation received renal BOLD examination again six months after surgery. The apparent transverse relaxation rate (R2*) values of the cortex and medulla at different times before and after transplantation were measured and recorded. The differences of R2* values between 30 donors' cortex and medulla in both kidneys before surgery were compared; the differences of R2* values between 30 pairs of subjects' cortex and medulla in remaining and donated kidney within 2 weeks before and after surgery were compared; variance gained through single factor repeated measurement was applied to analyze and compared the difference of R2* values between 15 pairs of follow-up subjects' cortex and medulla in remaining and donated kidney at different time points before and after surgery. Results All 60 subjects received MRI scan, and there was no statistical difference in R2* values between 30 subjects' cortex and medulla in both kidney before surgery (P>0.05). The difference between the cortex and medulla was statistically significant, with R2* value of medulla higher than that of cortex (P<0.01). R2* values of cortex and medulla of the remaining kidney in 30 subjects two weeks after receiving unilateral nephrectomy were lower than those before surgery. R2* value of cortex and medulla of donated kidney were both lowered before surgery, the difference of which was statistically significant (P<0.01). R2*values of cortex and medulla in remaining and donated kidney of 15 pairs of subjects who have received half a year's follow up were both evidently reduced two weeks after surgery, and R2* values six months after surgery were raised compared with two weeks after surgery, but were still lower than that before surgery, the difference of which were both statistically significant (P<0.05). Conclusion BOLD MRI can be used for longitudinal monitor of changes in blood oxygen levels in remaining and donated kidney after receiving parental kidney transplantation.
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Objective To investigate the clinical value of blood oxygenation level-dependent functional magnetic resonance imaging(BOLD-fMRI)in the protection of visual function during postoperative radiotherapy for occipital lobe gliomas. Methods Twenty-eight patients with occipital lobe gliomas receiving postoperative radiotherapy from 2014 to 2016 were enrolled as subjects. All patients underwent computed tomography(CT) simulation,conventional MRI,and BOLD-fMRI before radiotherapy. The location and scope of the visual cortex on 3DT1anatomical images were used to guide the labeling of the visual cortex on simulated CT images. A visual cortex protective radiotherapy plan and a conventional radiotherapy plan were made by intensity-modulated radiotherapy. The feasibility of the visual cortex protective radiotherapy plan was evaluated using conformity index(CI),homogeneity index(HI),Dmax,and Dmeanfor planning target volume(PTV)and Dmaxand Dmean to the visual cortex. Results For the two plans, if the effective dose to target volume was guaranteed and the doses to conventional organs at risk were acceptable, there were no significant differences in CI or HI for PTV between them(P=0.874,P=0.602).Compared with the conventional radiotherapy plan,the Dmaxand Dmeanto the ipsilateral visual cortex were reduced by 8.40% and 9.25%, respectively, while the Dmaxand Dmeanto the contralateral visual cortex were reduced by 13.26% and 14.77%, respectively, in the protective radiotherapy plan. Conclusions With a guaranteed prescribed dose to target volume and BOLD-fMRI used as a guide, the visual cortex protective radiotherapy, compared with the conventional plan, can reduce the dose to the visual cortex and protect the corresponding functional areas.
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Objective To evaluate the renal oxygenation in patients with primary nephrotic syndrome (PNS) using BOLD MRI.Methods Twenty patients with untreated first-onset PNS and 18 healthy control subjects underwent BOLD MRI.The R2* of renal cortex and medulla were measured.Blood and urine samples were obtained on the day of MRI,and the patients underwent renal biopsy after MRI.The renal tubulointerstitial damage scores (TIDS) were determined using Katafuchi criteria.All patients received corticosteroids within 7 days after MRI and were followed up for 12 months.The difference of R2* levels between the PNS patients and controls were compared,and the correlations between R2* values and TIDS,laboratory parameters (eGFR,etc.) were tested.Results R2* values of renal medulla in PNS patients significantly decreased compared that of the controls (t =-9.270,P＜0.001).R2* values of renal medulla in PNS patients were negatively correlated with eGFR (r=-0.462,P=0.040) and positively correlated with TIDS (r=0.809,P＜0.001).There was a slight tendency for higher R2* values of renal medulla in individuals with poor prognosis.Conclusion BOLD MRI is a noninvasive method for the detection of renal oxygenation changes,which can evaluate the renal function and tubulointerstitial impairment,as well as prediction of the prognosis for PNS patients.
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Differently from previous studies that used Transcranial Doppler (TCD) and functional MRI (fMRI) for cerebral vasomotor reactivity (CVR) assessment in patients with carotid stenosis (CS), we assessed CVR using an identical stimulus, the Breath-Holding Test (BHT). We included 15 patients with CS and 7 age-matched controls to verify whether fMRI responded differently to BHT between groups and to calculate the agreement rate between tests. For TCD, impaired CVR was defined when the mean percentage increase on middle cerebral artery velocities was ≤31% on 3 consecutive 30-s apnea intercalated by 4-min normal breathing intervals. For fMRI, the percent variation on blood oxygen level-dependent (BOLD) signal intensity in the lentiform nucleus (LN) ipsilateral to the CS (or both LNs for controls) from baseline breathing to apnea was measured. The Euclidian differences between the series of each subject and the series of controls and patients classified it into normal or impaired CVR. We found different percent variations on BOLD-signal intensities between groups (P=0.032). The agreement was good in Controls (85.7%; κ=0.69) and overall (77.3%; κ=0.54). We conclude that BHT was feasible for CVR assessment on fMRI and elicited different BOLD responses in patients and controls, with a good overall agreement between the tests.
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Humans , Male , Female , Middle Aged , Aged , Aged, 80 and over , Breath Holding , Carotid Stenosis/diagnostic imaging , Cerebrovascular Circulation/physiology , Oxygen/blood , Vasomotor System/diagnostic imaging , Blood Flow Velocity , Carotid Stenosis/physiopathology , Case-Control Studies , Magnetic Resonance Imaging , Ultrasonography, Doppler, Transcranial , Vasomotor System/physiopathologyABSTRACT
Objective To explore the similarities and differences in amplitude of low frequency fluctuation ( ALLF) between patients with first-episode drug-naive schizophrenia and offspring of schizophrenia patients.Methods ALFF values were estimated by measuring the Blood Oxygen Level-Dependent ( BOLD) signal using resting state function-al magnetic resonance imaging ( rs-fMRI) .The fMRI date were acquired from 23 patients with first-episode drug-naive schizophrenia (SZ), 25 offsprings of schizophrenia patients (OS) and 29 age -and gender -matched health controls ( HC) .The ALFF value of each subject was calculated by MATLAB-based DPARSF software.Results Compared with HC, the ALFF values of SZ and OS were significantly different in the left posterior part of the inferior temporal gyrus, left parahippocampal gyrus, left hippocampus, right postcentral gyrus and bilateral precuneus.The ALFF values were not signif-icantly different between these two groups in the aforementioned regions.Compared with OS and HC, the ALFF values of SZ were significantly different in the left anterior part of the inferior temporal gyrus, left temporal pole and bilateral calcarine cortex.But there was no significant difference between OS and HC.Conclusions The brain function is abnormal in pa-tients with early schizophrenia and offspring of schizophrenia patients.The significant difference of ALFF in the left posterior part of the inferior temporal gyrus, left parahippocampal gyrus, left hippocampus, right postcentral gyrus and bilateral pre-cuneus may suggest the heredodiathesis-related brain functional alterations.Significant difference of ALFF in the left ante-rior part of the inferior temporal gyrus and the left temporal pole bilateral calcarine cortex may suggest the disease-related brain alterations.
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Objective The BOLD -fMRI(blood oxygenation level dependent functional magnetic resonance imaging)was used to observe the functional cortical activities of the bilateral cerebral hemispheres in 23 cases of chil_dren with congenital sensorineural hearing loss under resting state ,and to further explore the values of BOLD-fM_RI in patients with sensorineural hearing loss .Methods Twenty three children with congenital sensorineural hearing loss were included in the experimental group and 10 normal heating children were included as cronol group .The ALFF(amplitude of low -frequency fluctuation) method was used to analyze the image data ,and to compare the ex_perimental and control groups with bilateral cerebral cortex function activities for the quantitative analysis .ResuIts The resting state activity intensity in the left inferior temporal gyrus ,left fusiform gyrus ,right cingulate gyrus and left post central gyrus of the experimental group were significantly greater than those of in the corresponding intensi_ty cortex of the control group (P< 0 .01) .ConcIusion The cortex of sensory systems in children with congenital sensorineural deafness may have functional remodeling ,cerebral cortex of patients with sensorineural hearing loss may have perception compensation phenomenon .
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OBJECTIVE: To assess the feasibility of susceptibility-weighted imaging (SWI) while monitoring changes in renal oxygenation level after water loading. MATERIALS AND METHODS: Thirty-two volunteers (age, 28.0 +/- 2.2 years) were enrolled in this study. SWI and multi-echo gradient echo sequence-based T2* mapping were used to cover the kidney before and after water loading. Cortical and medullary parameters were measured using small regions of interest, and their relative changes due to water loading were calculated based on baseline and post-water loading data. An intraclass correlation coefficient analysis was used to assess inter-observer reliability of each parameter. A receiver operating characteristic curve analysis was conducted to compare the performance of the two methods for detecting renal oxygenation changes due to water loading. RESULTS: Both medullary phase and medullary T2* values increased after water loading (p 0.05). Interobserver reliability was excellent for the T2* values, good for SWI cortical phase values, and moderate for the SWI medullary phase values. The area under receiver operating characteristic curve of the SWI medullary phase values was 0.85 and was not different from the medullary T2* value (0.84). CONCLUSION: Susceptibility-weighted imaging enabled monitoring changes in the oxygenation level in the medulla after water loading, and may allow comparable feasibility to detect renal oxygenation level changes due to water loading compared with that of T2* mapping.
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Adult , Female , Humans , Male , Young Adult , Kidney/metabolism , Magnetic Resonance Imaging/methods , Oxygen/blood , ROC Curve , Reproducibility of Results , Water/administration & dosageABSTRACT
AIM:To analyze the recovery of visual cortex activation range of color vision in anisometropia amblyopia children after treatment by using blood oxygen level dependence-functional magnetic resonance imaging ( BOLD- fMRI ) and SPM8 software. METHODS:Self-control study. This fMRI study directly compared activity in visual cortex produced by color monocular stimulation in 13 monocular anisometropia amblyopia children. The project of study was blocked design. The data of functions and anatomical MRI was stimulated by three-primary colors and was preprocessed and analyzed by SPM8 that based on MATLAB software. According to the data, we compared the change of the central area of color vision when first visit and 1, 2 ,4wk after treatment. RESULTS: The BA17, BA18, BA19 and BA37 of amblyopia children were different activated after they accepted the three-primary colors stimulation (PCONCLUSION: After 4wk treatment, visual cortex activation of color vision of anisometropia amblyopic children is expanded, but with low extent, after the short-term treatment of amblyopia, visual cortex activation of color vision has a certain degree of recovery but not obvious.
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Objective To explore the characteristics of blood oxygen level dependent (BOLD) magnetic resonance imaging (MRI) in healthy native kidneys. To investigate the relationship between BOLD-MRI and common physiological in-dexes. Methods GE 3.0T MRI scanner and Torsopa phased-array coil were employed to acquire renal coronal T1WI and BOLD image. Ninety patients who were ruled out chronic kidney diseases underwent BOLD-MRI with T2*-spoiled gradient recalled echo (T2*SPGR) sequence. BOLD images were analyzed on R2*map software. Cortical and medullary R2*values were analyzed in bilateral kidneys and in different gender. Different regional R2*values in cortex and medulla were also ana-lyzed. Physiological indices including age, body height and weight, body mass index (BMI), body surface area (BSA), estimat-ed glomerular filtration rate (eGFR) were recorded. Correlation between R2*value and physiological indices were analyzed. Results Bilateral renal cortical R2*values [left (16.56±1.40) Hz and right (16.66±1.28)Hz, respectively] were less than val-ues in medulla [left (28.82±3.71)Hz and right (28.36±3.72)Hz, respectively]. Female and male cortical R2*values [female (16.55±1.30Hz) and male (16.66±1.38)Hz, respectively] were also less than corresponding values in medulla [female (28.46± 3.64) Hz and male (28.70±3.78) Hz, respectively]. In bilateral renal medullary region, R2*values in low pole (27.29±3.05) Hz was less than values in middle (29.32±3.47) Hz and upper pole (29.16±4.21)Hz (F=15.184, P<0.001). Age was positive-ly correlated with R2* values in medulla (r =0.284, P =0.002). However, eGFR was negatively correlated with medullary R2*value (r=-0.232, P=0.007). Conclusion R2*values reflected the levels of renal partial pressure of oxygen and as-sessed the degree of renal ischemia. BOLD MRI could offer a simple, convenient and noninvasive method for to evaluate renal oxygen metabolism in cortex and medulla.
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PURPOSE: Renal blood oxygen level-dependent (BOLD) MRI has been used in the evaluation of renal oxygenation. We tried to provide the normal R2* value of the human kidney with 3.0 T, and evaluated the differences in R2* values according to gender and location. MATERIALS AND METHODS: Twenty-four healthy volunteers underwent BOLD MRI at 3.0 T. Multi gradient echo-echo planar imaging sequence with seventeen echoes was used. After generation of the T2* map, the R2* was calculated. The statistical differences in R2* values between the cortex and medulla, males and females, and the right and left kidney were analyzed. The regional differences of R2* within the both kidneys were evaluated respectively. RESULTS: BOLD MRI was successful in all participants. No gross artifact interfered with R2* measurement. The mean R2* at 3.0 T was 17.1 +/- 2.60 s-1 in the cortex and 27.7 +/- 4.83 s-1 in the medulla (p < 0.001). The R2* value in the medulla was significantly higher in the male than female volunteers (p = 0.025). There were no statistical differences of R2* according to the side and location in the kidney (p = 0.197). CONCLUSION: Renal BOLD MRI can be efficiently performed with 3.0 T MRI. Renal medullary hypoxia is present in normal volunteers. Our results may be used as reference values in the evaluation of pathologic conditions using BOLD MRI.
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Female , Humans , Male , Hypoxia , Artifacts , Kidney , Oxygen , Reference ValuesABSTRACT
Objective To explore what brain regions are modulated by heroin addiction and withdrawal.MethodsWe used functional magnetic resonance imaging to investigate the brain function in 15 heroin-dependent patients 3 days (acute) and 1 month (protracted) after heroin abstinence.Sixteen normal controls were included.Results The blood oxygen level-dependent signal in the orbitofrontal cortex of the brain of heroin-dependent patients was significantly elevated 3 days after the withdrawal.Hyperfunction of the orbitofrontal cortex declined 1 month after the withdrawal.Conclusion Heroin-dependent subjects at both 3 days and 1 month abstinence have persistent abnormalities in the brain function.Although some tangible beneficial effects are noted following 1month of detoxification,possible permanent damage to the brain caused by heroin use is suggested.
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Objective: To observe the signal changes of blood-oxygen-level-dependent functional MRI (BOLD-fMRI) in brain tissue after inhalation of oxygen. Methods: Fifteen volunteers, 9 males and 6 females, were included in the present experiment. The fMRI was conducted using 1.5T Singna Double-gradient Super Conducting Magnetic Resonance Imaging system (GE Inc). Bold-fMRI scanning was conducted using GRE-EPI sequence and data analysis was done using SPM2 software. Meanwhile, the BOLD-fMRI T2 signal changes after 15 s and 6 min inhalation of pure oxygen were observed and compared with those after inhaling normal air. Results: No obvious activation of BOLD-fMRI was observed in the whole brain after inhaling normal air. Fifteen seconds after inhaling pure oxygen, the signal changes in the whole brain mainly manifested as the signal decrease in the gray matter, with average signal change being (- 0.041 ± 0.31)% in the gray matter and about (0.056 ± 0.26)% in the white matter; the changes were significantly different from those of the normal air group (P<0.001). Six minutes after inhaling pure oxygen, signal changes in the whole brain mainly manifested as the signal increase in the white matter, with the average signal change being about (0.015±0.365)% in the gray matter and (0.14±0.278)% in the white matter; the changes were significantly different from those of the normal air group (P<0.001). Conclusion: Inhaling oxygen for different time periods can cause different BOLD signal changes in brain tissues. BOLD T2 signal in grey matter is decreased after short-time inhalation and is increased in white matter after long-time inhalation.
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Objective To study the characteristics of the hand motor cortex in ataxia patients during active and passive finger-to-thumb opposition movements using bold oxygenation level dependent functional magnetic resonance imaging (BOLD-fMRI). Methods Ten right-handed healthy volunteers and 16 ataxia patients with motor cortex lesions were selected, and whole-brain BOLD-fMRI examinations were made while the subjects were performing the active and passive movements. Activated volume and intensity were recorded from the corresponding motor cortex and analyzed quantitatively. Meanwhile, the patients' coordination was evaluated using the international cooperative ataxia rating scale (ICARS). Results During passive movement of the ataxia patient's affected hands, the ipsilateral supplementary motor area (SMA) activated volume was larger than that during normal ipsilateral hand movement, and the activation intensity was also higher than that in the healthy controls. The ipsilateral cerebellum activated volume and intensity were significantly lower than those in the control group, and the frequency of appearance of the cerebellum was also less. The patients' activated volume and intensity in the ipsilateral cerebellum showed no correlation with ICARS scores. Conclusions When the ataxia patients' affected side cerebellum was dysfunctional, the ipsilateral SMA could compensate for the weak cerebellum function. The ICARS does not reflect cerebellum function.