Diffusion tensor tractography allows the sensory fiber course of the medial lemniscus to be visualized. But diffusion tensor tractography for accurate evaluation of the repair of injured somatosensory tracts in stroke...Diffusion tensor tractography allows the sensory fiber course of the medial lemniscus to be visualized. But diffusion tensor tractography for accurate evaluation of the repair of injured somatosensory tracts in stroke patients has been rarely reported. A 55-year-old female patient presented with severe somatosensory dysfunction of the left side caused by a spontaneous intracerebral hemorrhage on the right side. The somatosensory function of the affected side recovered to a nearly normal state at 7 weeks from onset. Functional magnetic resonance imaging revealed that at 3 weeks from onset, there was no cortical activation by touch at each hand; at 7 weeks, the contralateral cortex centered on the primary sensory cortex was found to be activated during touch and passive movements, and activation by passive movements was increased compared with that at 3 weeks. Diffusion tensor tractography revealed that a medial lemniscus on the affected （right） hemisphere was not observed at 3 weeks from onset, however, at 7 weeks, the unaffected （left） hemisphere passed along the medial lemniscus pathway from the pons to the primary sensory cortex. These findings indicate that combined functional magnetic resonance imaging and diffusion tensor tractography would allow more accurate evaluation of the architecture and integrity of somatosensory tracts and is a useful method to investigate the recovery of somatosensory dysfunction in stroke patients.展开更多
Application of modern magnetic resonance imaging(MRI) techniques to the live fetus in utero is a relatively recent endeavor. The relative advantages and disadvantages of clinical MRI relative to the widely used and ac...Application of modern magnetic resonance imaging(MRI) techniques to the live fetus in utero is a relatively recent endeavor. The relative advantages and disadvantages of clinical MRI relative to the widely used and accepted ultrasonographic approach are the subject of a continuing debate; however the focus of this review is on the even younger field of quantitative MRI as applied to non-invasive studies of fetal brain development. The techniques covered under this header include structural MRI when followed by quan-titative(e.g., volumetric) analysis, as well as quantita-tive analyses of diffusion weighted imaging, diffusion tensor imaging, magnetic resonance spectroscopy and functional MRI. The majority of the published work re-viewed here reflects information gathered from normal fetuses scanned during the 3rd trimester, with relatively smaller number of studies of pathological samples including common congenital pathologies such as ven-triculomegaly and viral infection.展开更多
Background Tumor surgery in brain motor functional areas remains challenging. Novel techniques are being developed to gain maximal and safe resection for brain tumor surgery. Herein, we assessed the magnetic resonance...Background Tumor surgery in brain motor functional areas remains challenging. Novel techniques are being developed to gain maximal and safe resection for brain tumor surgery. Herein, we assessed the magnetic resonance diffusion tensor imaging （MR-DTI） and fluorescein sodium dyeing （FLS） guiding technique for surgery of glioma located in brain motor functional areas. Methods Totally 83 patients were enrolled according to our inclusion and exclusion criteria （56 patients in experimental group, 27 patients in control group）. In the experimental group, the surgical approach was designed by DTI imaging, which showed the relationship between the tumor and motor tract. The range of resection in the operation was determined using the FLS-stained area, which recognized the tumor and its infiltrated tissue. The traditional routine method was used in the control group. Postoperatively, all patients underwent enhanced brain MRI within 72 hours to ascertain the extent of resection. Patients were followed in our outpatient clinic over 6-24 months. Neurological deficits and Karnofsky scoring （KPS） were evaluated. Results There were no significant differences in balance test indexes of preoperative data （sex, age, lesion location and volume, and neurological deficits before operation） and diagnosis of histopathology between the two groups. There was a trend in the experimental group for greater rates of gross total resection （80.4% vs. 40.7%）, and the paralysis rate caused by surgery was lower in experimental （25.0%） vs. control （66.7%） groups （P 〈0.05）. The 6-month KPS in the low-grade and high-grade gliomas was 91＋11 and 73＋26, respectively, in the experimental group vs. 82＋9 and 43＋27, respectively, in the control group （P 〈0.05 for both）. Conclusions MR-DTI and FLS dye guiding for surgery of glioma located in brain motor functional areas can increase the gross total resection rate, decrease the paralysis rate caused by surgery, and improve patient quality of life compared with traditional glioma surgery.展开更多
Traumatic brain injury(TBI) is a major contributor of long-term disability and a leading cause of death worldwide. A series of secondary injury cascades can contribute to cell death, tissue loss, and ultimately to the...Traumatic brain injury(TBI) is a major contributor of long-term disability and a leading cause of death worldwide. A series of secondary injury cascades can contribute to cell death, tissue loss, and ultimately to the development of functional impairments. However, there are currently no effective therapeutic interventions that improve brain outcomes following TBI. As a result, a number of experimental TBI models have been developed to recapitulate TBI injury mechanisms and to test the efficacy of potential therapeutics. The pig model has recently come to the forefront as the pig brain is closer in size, structure, and composition to the human brain compared to traditional rodent models, making it an ideal large animal model to study TBI pathophysiology and functional outcomes. This review will focus on the shared characteristics between humans and pigs that make them ideal for modeling TBI and will review the three most common pig TBI models–the diffuse axonal injury, the controlled cortical impact, and the fluid percussion models. It will also review current advances in functional outcome assessment measures and other non-invasive, translational TBI detection and measurement tools like biomarker analysis and magnetic resonance imaging. The use of pigs as TBI models and the continued development and improvement of translational assessment modalities have made significant contributions to unraveling the complex cascade of TBI sequela and provide an important means to study potential clinically relevant therapeutic interventions.展开更多
This paper briefly summarizes the development of magnetic resonance imaging and spectroscopy in medicine.Aspects of magnetic resonancephysics and-technology relevant at ultra-high magnetic fields as well as current li...This paper briefly summarizes the development of magnetic resonance imaging and spectroscopy in medicine.Aspects of magnetic resonancephysics and-technology relevant at ultra-high magnetic fields as well as current limitations are highlighted.Based on the first promising studies,potential clinical applications at 7 Tesla are suggested.Other aims are to stimulate awareness of the potential of ultra-high field magnetic resonance and to stimulate active participation in much needed basic or clinical research at 7 Tesla or higher.展开更多
目的探究女性乳腺癌患者术前新辅助化疗后脑静息态功能和类淋巴功能变化及其之间的相关性。方法40名健康女性被试及80名女性乳腺癌患者被纳入本次研究,乳腺癌患者均进行术前新辅助化疗。应用MMSE、DSST和FACT-CogPCI评分评估被试认知功...目的探究女性乳腺癌患者术前新辅助化疗后脑静息态功能和类淋巴功能变化及其之间的相关性。方法40名健康女性被试及80名女性乳腺癌患者被纳入本次研究,乳腺癌患者均进行术前新辅助化疗。应用MMSE、DSST和FACT-CogPCI评分评估被试认知功能。应用rsfMRI获取反映大脑功能活动的ALFF指标。应用DTI-ALPS技术获取反映脑类淋巴功能的ALPS指数。分析乳腺癌患者化疗前后ALFF及ALPS变化,分析各指标与认知评分之间的相关性,并分析ALFF与ALPS之间的相关性情况。结果乳腺癌患者化疗后MMSE、DSST及FACT-CogPCI评分均减低(P<0.05)。化疗后,左侧颞极中部、左侧丘脑腹外侧核及右侧顶后中回团块ALFF值减低,双侧颞叶、枕叶及顶叶多个脑区的ALFF值与FACTCogPCI评分呈正相关(pFDR-C<0.001)。化疗后ALPS指数相比正常被试增高(1.42±0.29 vs 1.56±0.24,P=0.011),同时ALPS指数与FACT-CogPCI评分呈正相关(r=0.241,P=0.04)。与此同时化疗后左侧舌状回ALFF值与ALPS指数呈正相关(r=0.69,P<0.001)。结论研究结果提示,大脑功能活动和类淋巴引流均参与化疗后认知功能改变的过程,同时两者存在相关性。展开更多
This short review examines the most recent functional studies of the topographic organization of the human corpus callosum, the main interhemispheric commissure. After a brief description of its anatomy, development, ...This short review examines the most recent functional studies of the topographic organization of the human corpus callosum, the main interhemispheric commissure. After a brief description of its anatomy, development, microstructure, and function, it examines and discusses the latest findings obtained using diffusion tensor imaging(DTI) and tractography(DTT) and functional magnetic resonance imaging(f MRI), three recently developed imaging techniques that have significantly expanded and refined our knowledge of the commissure. While DTI and DTT have been providing insights into its microstructure, integrity and level of myelination, f MRI has been the key technique in documenting the activation of white matter fibers, particularly in the corpus callosum. By combining DTT and f MRI it has been possible to describe the trajectory of the callosal fibers interconnecting the primary olfactory, gustatory, motor, somatic sensory, auditory and visual cortices at sites where the activation elicited by peripheral stimulation was detected by fMRI. These studies have demonstrated the presence of callosal fiber tracts that cross the commissure at the level of the genu, body, and splenium, at sites showing f MRI activation. Altogether such findings lend further support to the notion that the corpus callosum displays a functional topographic organization that can be explored with f MRI.展开更多
AIM:To assess the clinical diagnostic value of functional imaging,combining quantitative parameters of apparent diffusion coefficient(ADC) and standardized uptake value(SUV)max,before and after chemo-radiation therapy...AIM:To assess the clinical diagnostic value of functional imaging,combining quantitative parameters of apparent diffusion coefficient(ADC) and standardized uptake value(SUV)max,before and after chemo-radiation therapy,in prediction of tumor response of patients with rectal cancer,related to tumor regression grade at histology.METHODS:A total of 31 patients with biopsy proven diagnosis of rectal carcinoma were enrolled in our study.All patients underwent a whole body ^(18)FDG positron emission tomography(PET)/computed tomography(CT) scan and a pelvic magnetic resonance(MR)examination including diffusion weighted(DW) imaging for staging(PET1,RM1) and after completion(6.6 wk)of neoadjuvant treatment(PET2,RM2).Subsequently all patients underwent total mesorectal excision and the histological results were compared with imaging findings.The MR scanning,performed on 1.5 T magnet(Philips,Achieva),included T2-weighted multiplanar imaging and in addition DW images with b-value of 0 and 1000 mm^2/s.On PET/CT the SUVmax of the rectal lesion were calculated in PET1 and PET2.The percentage decrease of SUVmax(△SUV) and ADC(△ADC) values from baseline to presurgical scan were assessed and correlated with pathologic response classified as tumor regression grade(Mandard's criteria;TRG1 = complete regression,TRG5 = no regression).RESULTS:After completion of therapy,all the patients were submitted to surgery.According to the Mandard's criteria,22 tumors showed complete(TRG1) or subtotal regression(TRG2) and were classified as responders;9tumors were classified as non responders(TRG3,4 and5).Considering all patients the mean values of SUVmax in PET 1 was higher than the mean value of SUVmax in PET 2(P < 0.001),whereas the mean ADC values was lower in RM1 than RM2(P < 0.001),with a △SUV and △ADC respectively of 60.2%and 66.8%.The best predictors for TRG response were SUV2(threshold of4.4) and ADC2(1.29 × 10^(-3) mm^2/s) with high sensitivity and specificity.Combining in a single analysis both the obtained median value,the positive predictive value,in predicting the different group category response in related to TRG system,presented R^2 of 0.95.CONCLUSION:The functional imaging combining ADC and SUVmax in a single analysis permits to detect changes in cellular tissue structures useful for the assessment of tumour response after the neoadjuvant therapy in rectal cancer,increasing the sensitivity in correct depiction of treatment response than either method alone.展开更多
基金the National Research Foundation of Korea Grant Funded by the Korean Government,No.KRF-2008-314-E00173
文摘Diffusion tensor tractography allows the sensory fiber course of the medial lemniscus to be visualized. But diffusion tensor tractography for accurate evaluation of the repair of injured somatosensory tracts in stroke patients has been rarely reported. A 55-year-old female patient presented with severe somatosensory dysfunction of the left side caused by a spontaneous intracerebral hemorrhage on the right side. The somatosensory function of the affected side recovered to a nearly normal state at 7 weeks from onset. Functional magnetic resonance imaging revealed that at 3 weeks from onset, there was no cortical activation by touch at each hand; at 7 weeks, the contralateral cortex centered on the primary sensory cortex was found to be activated during touch and passive movements, and activation by passive movements was increased compared with that at 3 weeks. Diffusion tensor tractography revealed that a medial lemniscus on the affected （right） hemisphere was not observed at 3 weeks from onset, however, at 7 weeks, the unaffected （left） hemisphere passed along the medial lemniscus pathway from the pons to the primary sensory cortex. These findings indicate that combined functional magnetic resonance imaging and diffusion tensor tractography would allow more accurate evaluation of the architecture and integrity of somatosensory tracts and is a useful method to investigate the recovery of somatosensory dysfunction in stroke patients.
文摘Application of modern magnetic resonance imaging(MRI) techniques to the live fetus in utero is a relatively recent endeavor. The relative advantages and disadvantages of clinical MRI relative to the widely used and accepted ultrasonographic approach are the subject of a continuing debate; however the focus of this review is on the even younger field of quantitative MRI as applied to non-invasive studies of fetal brain development. The techniques covered under this header include structural MRI when followed by quan-titative(e.g., volumetric) analysis, as well as quantita-tive analyses of diffusion weighted imaging, diffusion tensor imaging, magnetic resonance spectroscopy and functional MRI. The majority of the published work re-viewed here reflects information gathered from normal fetuses scanned during the 3rd trimester, with relatively smaller number of studies of pathological samples including common congenital pathologies such as ven-triculomegaly and viral infection.
文摘Background Tumor surgery in brain motor functional areas remains challenging. Novel techniques are being developed to gain maximal and safe resection for brain tumor surgery. Herein, we assessed the magnetic resonance diffusion tensor imaging （MR-DTI） and fluorescein sodium dyeing （FLS） guiding technique for surgery of glioma located in brain motor functional areas. Methods Totally 83 patients were enrolled according to our inclusion and exclusion criteria （56 patients in experimental group, 27 patients in control group）. In the experimental group, the surgical approach was designed by DTI imaging, which showed the relationship between the tumor and motor tract. The range of resection in the operation was determined using the FLS-stained area, which recognized the tumor and its infiltrated tissue. The traditional routine method was used in the control group. Postoperatively, all patients underwent enhanced brain MRI within 72 hours to ascertain the extent of resection. Patients were followed in our outpatient clinic over 6-24 months. Neurological deficits and Karnofsky scoring （KPS） were evaluated. Results There were no significant differences in balance test indexes of preoperative data （sex, age, lesion location and volume, and neurological deficits before operation） and diagnosis of histopathology between the two groups. There was a trend in the experimental group for greater rates of gross total resection （80.4% vs. 40.7%）, and the paralysis rate caused by surgery was lower in experimental （25.0%） vs. control （66.7%） groups （P 〈0.05）. The 6-month KPS in the low-grade and high-grade gliomas was 91＋11 and 73＋26, respectively, in the experimental group vs. 82＋9 and 43＋27, respectively, in the control group （P 〈0.05 for both）. Conclusions MR-DTI and FLS dye guiding for surgery of glioma located in brain motor functional areas can increase the gross total resection rate, decrease the paralysis rate caused by surgery, and improve patient quality of life compared with traditional glioma surgery.
文摘Traumatic brain injury(TBI) is a major contributor of long-term disability and a leading cause of death worldwide. A series of secondary injury cascades can contribute to cell death, tissue loss, and ultimately to the development of functional impairments. However, there are currently no effective therapeutic interventions that improve brain outcomes following TBI. As a result, a number of experimental TBI models have been developed to recapitulate TBI injury mechanisms and to test the efficacy of potential therapeutics. The pig model has recently come to the forefront as the pig brain is closer in size, structure, and composition to the human brain compared to traditional rodent models, making it an ideal large animal model to study TBI pathophysiology and functional outcomes. This review will focus on the shared characteristics between humans and pigs that make them ideal for modeling TBI and will review the three most common pig TBI models–the diffuse axonal injury, the controlled cortical impact, and the fluid percussion models. It will also review current advances in functional outcome assessment measures and other non-invasive, translational TBI detection and measurement tools like biomarker analysis and magnetic resonance imaging. The use of pigs as TBI models and the continued development and improvement of translational assessment modalities have made significant contributions to unraveling the complex cascade of TBI sequela and provide an important means to study potential clinically relevant therapeutic interventions.
文摘This paper briefly summarizes the development of magnetic resonance imaging and spectroscopy in medicine.Aspects of magnetic resonancephysics and-technology relevant at ultra-high magnetic fields as well as current limitations are highlighted.Based on the first promising studies,potential clinical applications at 7 Tesla are suggested.Other aims are to stimulate awareness of the potential of ultra-high field magnetic resonance and to stimulate active participation in much needed basic or clinical research at 7 Tesla or higher.
文摘目的探究女性乳腺癌患者术前新辅助化疗后脑静息态功能和类淋巴功能变化及其之间的相关性。方法40名健康女性被试及80名女性乳腺癌患者被纳入本次研究,乳腺癌患者均进行术前新辅助化疗。应用MMSE、DSST和FACT-CogPCI评分评估被试认知功能。应用rsfMRI获取反映大脑功能活动的ALFF指标。应用DTI-ALPS技术获取反映脑类淋巴功能的ALPS指数。分析乳腺癌患者化疗前后ALFF及ALPS变化,分析各指标与认知评分之间的相关性,并分析ALFF与ALPS之间的相关性情况。结果乳腺癌患者化疗后MMSE、DSST及FACT-CogPCI评分均减低(P<0.05)。化疗后,左侧颞极中部、左侧丘脑腹外侧核及右侧顶后中回团块ALFF值减低,双侧颞叶、枕叶及顶叶多个脑区的ALFF值与FACTCogPCI评分呈正相关(pFDR-C<0.001)。化疗后ALPS指数相比正常被试增高(1.42±0.29 vs 1.56±0.24,P=0.011),同时ALPS指数与FACT-CogPCI评分呈正相关(r=0.241,P=0.04)。与此同时化疗后左侧舌状回ALFF值与ALPS指数呈正相关(r=0.69,P<0.001)。结论研究结果提示,大脑功能活动和类淋巴引流均参与化疗后认知功能改变的过程,同时两者存在相关性。
基金Supported by Ministero Istruzione,Universitàe Ricerca(MIURPRIN 2007,2009)
文摘This short review examines the most recent functional studies of the topographic organization of the human corpus callosum, the main interhemispheric commissure. After a brief description of its anatomy, development, microstructure, and function, it examines and discusses the latest findings obtained using diffusion tensor imaging(DTI) and tractography(DTT) and functional magnetic resonance imaging(f MRI), three recently developed imaging techniques that have significantly expanded and refined our knowledge of the commissure. While DTI and DTT have been providing insights into its microstructure, integrity and level of myelination, f MRI has been the key technique in documenting the activation of white matter fibers, particularly in the corpus callosum. By combining DTT and f MRI it has been possible to describe the trajectory of the callosal fibers interconnecting the primary olfactory, gustatory, motor, somatic sensory, auditory and visual cortices at sites where the activation elicited by peripheral stimulation was detected by fMRI. These studies have demonstrated the presence of callosal fiber tracts that cross the commissure at the level of the genu, body, and splenium, at sites showing f MRI activation. Altogether such findings lend further support to the notion that the corpus callosum displays a functional topographic organization that can be explored with f MRI.
文摘AIM:To assess the clinical diagnostic value of functional imaging,combining quantitative parameters of apparent diffusion coefficient(ADC) and standardized uptake value(SUV)max,before and after chemo-radiation therapy,in prediction of tumor response of patients with rectal cancer,related to tumor regression grade at histology.METHODS:A total of 31 patients with biopsy proven diagnosis of rectal carcinoma were enrolled in our study.All patients underwent a whole body ^(18)FDG positron emission tomography(PET)/computed tomography(CT) scan and a pelvic magnetic resonance(MR)examination including diffusion weighted(DW) imaging for staging(PET1,RM1) and after completion(6.6 wk)of neoadjuvant treatment(PET2,RM2).Subsequently all patients underwent total mesorectal excision and the histological results were compared with imaging findings.The MR scanning,performed on 1.5 T magnet(Philips,Achieva),included T2-weighted multiplanar imaging and in addition DW images with b-value of 0 and 1000 mm^2/s.On PET/CT the SUVmax of the rectal lesion were calculated in PET1 and PET2.The percentage decrease of SUVmax(△SUV) and ADC(△ADC) values from baseline to presurgical scan were assessed and correlated with pathologic response classified as tumor regression grade(Mandard's criteria;TRG1 = complete regression,TRG5 = no regression).RESULTS:After completion of therapy,all the patients were submitted to surgery.According to the Mandard's criteria,22 tumors showed complete(TRG1) or subtotal regression(TRG2) and were classified as responders;9tumors were classified as non responders(TRG3,4 and5).Considering all patients the mean values of SUVmax in PET 1 was higher than the mean value of SUVmax in PET 2(P < 0.001),whereas the mean ADC values was lower in RM1 than RM2(P < 0.001),with a △SUV and △ADC respectively of 60.2%and 66.8%.The best predictors for TRG response were SUV2(threshold of4.4) and ADC2(1.29 × 10^(-3) mm^2/s) with high sensitivity and specificity.Combining in a single analysis both the obtained median value,the positive predictive value,in predicting the different group category response in related to TRG system,presented R^2 of 0.95.CONCLUSION:The functional imaging combining ADC and SUVmax in a single analysis permits to detect changes in cellular tissue structures useful for the assessment of tumour response after the neoadjuvant therapy in rectal cancer,increasing the sensitivity in correct depiction of treatment response than either method alone.
