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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 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 analyze the feasibility of incorporation of tracking visual pathway fiber bundles by diffusion tensor imaging ( DTI) in computed tomography ( CT) simulation to develop a protective radiotherapy regimen for cerebral gliomas.Methods A total of 31 patients with cerebral gliomas who were admitted to our hospital from 2013 to 2015 and planed to receive postoperative radiotherapy were enrolled as subjects.All patients underwent CT simulation, conventional or contrast-enhanced magnetic resonance imaging, and DTI.The obtained DTI images of visual pathway fiber bundles were fused with 3DT1 anatomical scans and then imported into the treatment planning system.A protective treatment plan ( setting the entire visual pathway fiber bundles as organs at risk (OARs)) and a conventional treatment plan were made for intensity-modulated radiotherapy ( IMRT) .Comparison of treatment outcomes was made by paired t test.Results There were no significant differences in the conformity index and heterogeneity index of the planning target volume between the two treatment plans ( P=0.875,0.597), both of which had sufficient radiation doses to the target volume and conventional OARs protected.For the patients undergoing the protective treatment plan, the Dmax and Dmean values were reduced to 9.01%and 9.05%, respectively, in the ipsilateral optic tract and to 17.96%and 15.52%, respectively, in the contralateral optic tract;the Dmax and Dmean values were reduced to 5.37%and 5.48%(P=0.000), respectively, in the ipsilateral optic radiation tract and to 12.89%and 11.21%( P=0.000) , respectively, in the contralateral optic radiation tract.Conclusions The protective treatment plan based on CT simulation combined with the display of visual pathway fiber bundles by DTI can reduce the radiation dose to the entire visual pathway fiber bundles, which keeps the risk of visual dysfunction after radiotherapy as low as possible.
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Objective To explore the relationship between the amount of bleeding and the histopathologic grade of cerebral glioma with susceptibility weighted imaging (SWI), so that to assess the diagnostic value of SWI in grading cerebral glioma. Methods Totally 30 patients with cerebral glioma underwent SWI. The area of hemorrhage of every slice displayed in SWI was measured with software. The rate and amount of bleeding were compared between high and low grade tumors. Results There was no statistical significance in the incidence of detected bleeding on SWI (P=0.064), though it was higher in highly malignant group (80.00%) than that in low grade group (46.67%), while there was statistical significance in the amount of bleeding detected on SWI (Z=-2.275, P=0.026) between highly malignant group and low grade group. Conclusion The amount of tumor hemorrhage displayed in SWI is valuable for the preoperative grading of cerebral glioma.
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Background and purpose: Cerebral gliomas is one of the common brain tumors, and has a poor prognosis. Therefore, multidisciplinary treatment strategy has been much investigated recently. This study investigated the efficacy of 3 dimensional conformal radiotherapy (3D-CRT) concurrent with Temozolomide chemotherapy in the treatment of postoperative cerebral gliomas. Methods: Sixty-two patients with cerebral glioma who had residual tumor surgery after surgery were randomized into 3D-CRT group (radiotherapy group, n=31) and 3D-CRT concurrent chemotherapy group (chemoradiotherapy group, n=31) prospectively. All patients received a dose of 50-60Gy/25-30F/5-6 weeks by 6MV-X ray, 1fx/day, 5 times a week. Chemotherapy regimen was Temozolomide: 75 mg/(m~2·d),concomitantly with radiotherapy,followed by 150-200mg/(m~2·d)for 5 days,28 days per cycle for total 3-6 cycles. Results: The total response rate was 35.3% (11/31) in the radiotherapy group, and 61.3% (19/31) in the chemoradiotherapy group. The difference was significant (P=0.042). But no significant difference was observed in terms of survival in the two groups (P=0.263). Stratified analysis showed that patients with grade Ⅲ gliomas in chemoradiotherapy group had better prognosis than those in the radiotherapy group (P=0.043). Conclusion. 3D-CRT concurrent with chemotherapy can improve the survival of pathological grade Ⅲ gliomas.