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Objective To investigate the change of diffusion tensor imaging (DTI) parameters on extracorticospinal tract and some domain in Parkinson disease (PD), and to explore the relationship between DTI parameters and PD. Methods Ten PD patients with unilateral symptoms and 20 with bilateral symptoms were enrolled in PD group 1 and PD group 2, respectively. Control group included 30 volunteers whose age and sex matched with those of PD group. PD patients and the subjects in control group underwent routine MR plain scan and DTI scan. FA and ADC maps were obtained after postprocessing. FA values and ADC values of ROI (region of interest) were measured. ROI included substantia nigra (SN), red nucleus (NR), globus pallidus (GP), putamen (PUT), caudate nucleus (CN), thalamus, genu of corpus callosum, splenium of corpus callosum, callosal gyrus, white matter of frontal lobe and anterior centra gyrus. All data were analyzed statistically. Results FA value of SN, CN, thalamus and splenium of corpus callosum of PD group degraded obviously compared with that of control group (P<0.05). FA value of PD group 1 was lower than control group and PD group 2 at anterior central gyrus and callosal gyrus (P<0.05). There was no significant difference of FA value among PD groups and control group at other ROI's. There was negative correlation between the changes of FA value at SN and PD grade. No significant difference was found in ADC value among PD group 1, PD group 2 and control group, but there was an increasing tendency of ADC value along with the progress of PD. Conclusion FA values of SN, CN, thalamus and splenium of corpus callosum can offer some important information for the early diagnosis of PD. DTI is useful for the study about PD's pathomechanism and clinical manifestation in vivo.
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l 1H-MRS was good for clinical purpose.
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The value of combined application of both ECG-gated cine MRA and 3D-CEMRA in the detection of large intracranial aneurysms was evaluated and the findings were compared with those of conventional MRA and DSA. Twenty-four patients with 26 large intracranial aneurysms underwent MRI and DSA. All these aneurysms, diameter from 15 to 39 mm, were located at internal cerebral artery (n=12), vertebral artery (n=3), basilar artery (n=4), anterior cerebral artery (n=2), middle cerebral artery (n=2), anterior communicate artery (n=2) and posterior communicate artery (n=1). Thirteen cases of hematoma or cavernoma were studied as control group. All patients were examined on GE 1.5T MR system. ECG-gated cine MRA was performed with 2D multi-phase fast gradient-recalled echo sequence in a single section. All the images were analyzed with signal intensity VS time curve for differentiating intraaneurysmal blood flow from static tissue. The results were analyzed by statistic "t" test. 3D-CEMRA was performed with spoiled gradient-recalled echo and one dose of Gd-DTPA. All data was processed with multi-plannar reformat (MPR) and tomography for the demonstration of aneurysms in detail. All 26 aneurysms were demonstrated successfully by combined application of both cine MRA and 3D-CEMRA. Compared to DSA and conventional 3D-MOTSA, its sensitivity and specificity figures were both 100%. Cine MRA could differentiate the blood flow from the static tissue. The intensity VS time curves of intraaneurysmal blood flow offered fluctuating form and average signal change between systole and diastole period was about 89.8 +/- 37.4; However, under the control group, intraaneurysmal thrombus or cerebral hemorrhage or cavernomas had no significant signal change and the curves offered steady form with the average signal change being about 8.2 +/- 6.3. There was statistically significant difference between the intraaneurysmal blood flow and static tissue (P=0.025, <0.05). 3D-CEMRA was very useful in demonstrating the aneurysmal size, intraaneurysmal thrombus formation, neck and the detailed relationship of the aneurysm to the surrounding structures. It was concluded that the combined application of both cine MRA and 3D-CEMRA might be a valuable clinical tool for the detection of large intracranial aneurysms.
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Angiography, Digital Subtraction , Contrast Media , Evaluation Studies as Topic , Image Enhancement , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Methods , Intracranial Aneurysm , Diagnosis , Magnetic Resonance Angiography , Methods , Magnetic Resonance Imaging, CineABSTRACT
The value of combined application of both ECG-gated cine MRA and 3D-CEMRA in the detection of large intracranial aneurysms was evaluated and the findings were compared with those of conventional MRA and DSA. Twenty-four patients with 26 large intracranial aneurysms underwent MRI and DSA. All these aneurysms, diameter from 15 to 39 mm, were located at internal cerebral artery (n=12), vertebral artery (n=3), basilar artery (n=4), anterior cerebral artery (n=2), middle cerebral artery (n=2), anterior communicate artery (n=2) and posterior communicate artery (n=1). Thirteen cases of hematoma or cavernoma were studied as control group. All patients were examined on GE 1.5T MR system. ECG-gated cine MRA was performed with 2D multi-phase fast gradient-recalled echo sequence in a single section. All the images were analyzed with signal intensity VS time curve for differentiating intraaneurysmal blood flow from static tissue. The results were analyzed by statistic "t" test. 3D-CEMRA was performed with spoiled gradient-recalled echo and one dose of Gd-DTPA. All data was processed with multi-plannar reformat (MPR) and tomography for the demonstration of aneurysms in detail. All 26 aneurysms were demonstrated successfully by combined application of both cine MRA and 3D-CEMRA. Compared to DSA and conventional 3D-MOTSA, its sensitivity and specificity figures were both 100%. Cine MRA could differentiate the blood flow from the static tissue. The intensity VS time curves of intraaneurysmal blood flow offered fluctuating form and average signal change between systole and diastole period was about 89.8 +/- 37.4; However, under the control group, intraaneurysmal thrombus or cerebral hemorrhage or cavernomas had no significant signal change and the curves offered steady form with the average signal change being about 8.2 +/- 6.3. There was statistically significant difference between the intraaneurysmal blood flow and static tissue (P=0.025, <0.05). 3D-CEMRA was very useful in demonstrating the aneurysmal size, intraaneurysmal thrombus formation, neck and the detailed relationship of the aneurysm to the surrounding structures. It was concluded that the combined application of both cine MRA and 3D-CEMRA might be a valuable clinical tool for the detection of large intracranial aneurysms.
Subject(s)
Angiography, Digital Subtraction , Contrast Media , Evaluation Study , Image Enhancement , Image Processing, Computer-Assisted , Imaging, Three-Dimensional/methods , Intracranial Aneurysm/diagnosis , Magnetic Resonance Angiography/methods , Magnetic Resonance Imaging, CineABSTRACT
<p><b>OBJECTIVE</b>To evaluate the value of magnetic resonance imaging (MRI) and three dimensional (3D) contrast magnetic resonance angiography (MRA) in the diagnosis of complications of simultaneous pancreas-kidney transplantation (SPKT), as confirmed by biopsy and digital subtraction angiography (DSA).</p><p><b>METHODS</b>Five MR examinations of five patients were performed within 28 days to 2 years after surgery on GE 1.5T MR system. Imaging techniques included axial and sagittal chemical fat-suppressed T1-weighted image (T1WI) and T2-weighted image (T2WI), additional contrast axial or saggital chemical fat-suppressed T1WI were obtained after 3D contrast MRA for calculating the mean percentage of the parenchymal enhancement (MPPE) of the pancreas and kidney. 3D contrast MRA was performed with Smartprep technique. MRA data were analyzed with maximum intensity projection (MIP) and multi-planner reformat (MPR).</p><p><b>RESULTS</b>In five cases of transplant pancreases, MRI found two normal pancreas grafts, one case of acute rejection, one case of chronic rejection with 70% fibrosis and one case of late pancreatitis. In five transplant kidneys, MRI detected four normal kidney grafts and one case of acute rejection with infarction. MPPE could distinguish infarction from other complications. 3D contrast MRA could display vascular complications of SPKT, such as stenosis or occlusion, aneurysm formation of transplanted vessels and narrowing at the site of anastomosis, as confirmed by DSA.</p><p><b>CONCLUSION</b>With combined application of MRI and 3D contrast MRA, complications of SPKT can be clearly identified.</p>
Subject(s)
Adult , Female , Humans , Male , Middle Aged , Image Enhancement , Imaging, Three-Dimensional , Kidney Transplantation , Magnetic Resonance Angiography , Magnetic Resonance Imaging , Pancreas TransplantationABSTRACT
Objective To evaluate the diagnostic value of in vivo 1H-MRS in the hyper acute reaction stage of radiation-induced brain injury after nasopharyngeal carcinoma radiotherapy. Methods Eighteen patients with nasopharyngeal carcinoma accepted radiotherapy for the first time. Bilateral temporal lobes in all cases were examined by conventional MRI and 1H-MRS before and after radiotherapy with radiation dose of 20 Gy, 40 Gy, and 60 Gy, respectively. MR image was performed with T_1-weighted gradient- and spin-echo, T_2-weighted spin-echo, fluid-attenuated inversion-recovery, and point resolution spectroscopy. The change of the spectroscopic morphology and the ratios of the metabolites were observed. Results There were no changes of signal in the temporal lobes with conventional MRI, but the peak height of NAA and Cho decreased obviously in the anterior half of the temporal lobes with 1H-MRS after radiotherapy. The post-radiotherapy changes of different metabolic peak in the anterior temporal lobes presented as two types: one type was that Cho and NAA peak were of the same height simultaneously. There were 20 locations (56%) of the 36 reaching the peak when accepting 20 Gy, 22 (61%) when accepting 40 Gy, and 13 (36%) when accepting 60 Gy, respectively. The other type was that Cho peak became the highest, whereas NAA peak was obviously lower and decreased to be the second highest. There were 4 locations(11%) of the 36 reaching the peak when accepting 20 Gy, 10 (28%) when accepting 40 Gy, and 23 (64%) when accepting 60 Gy, respectively. The ratio of Cho/Cr, NAA/Cr, and NAA/Cho decreased in the same position too. In addition, there was positive correlation between the ratios of the metabolites and the dose of radiotherapy.Conclusion 1H-MRS can be used to diagnose the radiation-induced injury of the brain in early acute reaction stage after nasopharyngeal carcinoma radiotherapy through reflecting histiocytic metabolism, and provide objective basis for pathology development and cellular metabolism study, also it can provide feasible projects for the clinic.