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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 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 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 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.
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Objective To investigate activation patterns in the motor cortex of patients with cerebral infarction by blood oxygen level dependent-functional magnetic resonance imaging ( BOLD-fMRI) , and to explore the brain's functional reorganization mechanism. Methods Sixteen patients ( 12 men and 4 women, age 37 to 80, mean 61.0±11.3) who had suffered a subcortical infarction within the previous 3 months were studied. All the patients received fMRI scanning during passive flexion-extension movement of both the affected and unaffected wrist separately.Brain functional mapping was acquired with SPM2 software. Activation patterns in the brain were compared between the affected and unaffected hands. Results The volume and intensity of the activated areas were diverse, but showed some order. When the affected hand moved, the fMRI map showed general hyperactivation. When the unaffected hand moved, the contralateral M1 and S1 were activated. Conclusions After cerebral infarction, the brain cortex showed compensatory changes. As the main motor cortex (M1) was deactivated, the subsidiary motor areas such as the PMC, SMA, CMA, IPL, PFC and CRB were activated. The activated motor areas could shift to the area around the lesion, and the non-motor area was activated also.