Application Development Of Susceptibility Weighted Imaging In Cerebrovascular Disease

Part 1 The Application of Susceptibility Weighted Imaging in Diagnosis of Intracranial Cavernous AngiomaObjective: To compare conventional MRI sequences images with susceptibility weighted imaging (SWI) images and study the diagnostic value of susceptibility weighted imaging in intracranial cavernous angiomas.Method:37 cases cavernous angiomas were collected and scaned with axial, sagittal T₁WI, axial T₂WI and SWI. SWI sequence was compared with the conventional MRI sequences in detecting and diagnosing cerebral vascular malformations. The statistics of the above results were got by means of Chi-square test to compare whether T₁WI, T₂WI and SWI were different in the detection rate of cavernous angiomas.Results: In 37 cases there were only one lesion in 32 cases, multiple lesions in 5 cases.67 lesions were detected (1 case with 21 lesions).On T₁WI sequences there were only one lesion in 30 cases, multiple lesions in 5 cases (1 case with 6 lesions). On T₂WI sequences there were only one lesion in 31 cases, multiple lesions in 5 cases (1 case with 12 lesions). On SWI sequences there were only one lesion in 32 cases, multiple lesions in 5 cases (1 case with 21 lesions). A total of 67 lesions were detected by SWI, 54 by T₁WI and 60 by T₂WI. The detection rate of cavernous angiomas on T₁WI, T₂WI and SWI were compared,χ² = 14.103,P=0.001 ( P < 0.05 ) .There were significant difference on the cavernous angiomas detection rate on SWI and conventional MRI sequences.The cavernous angiomas lesions appeared as iso, hyperintensity, hypointensity or heterogeneous signal intensity on TIWI and T₂WI sequences.30 cases on T₁WI and 36 cases on T₂WI were showed"popcorn sign", and the"ironhoop"sign could be seen in 4 cases on T₁WI and 27 cases on T₂WI.The lesions showed hypointensity in 31 cases, hypointersity with iso or hyperintensity shaped with point, patches in 35 cases on SWI, and"ironhoop"sign was showed. The range of the lesions was larger than that in conventional MRI sequences.Conclusion: SWI sequence has more sensitivity than conventional MRI sequences in detecting the intracranial cavernous angiomas.SWI has very important value in diagnosing intracranial cavernous angiomas.Part 2 The Application of Susceptibility Weighted Imaging in Diagnosis of Cerebral Venous MalformationObjective: To observe and analyze the conventional MRI and susceptibility weighted imaging performance of cerebral venous malformation, and study the diagnostic value of susceptibility weighted imaging (SWI) in cerebral venous malformation.Methods: The imaging data of the 21 patients with cerebral venous malformation were retrospectively analyzed. All of the patients were scaned with axial, sagittal T₁WI, axial T₂WI and SWI. SWI sequence was compared with the conventional MRI sequences; value the superiority of the SWI in showing the cerebral venous malformation.Results: Of the 21 cases with cerebral venous malformation, the locations were frontal lobes (10 lesions), parietal lobes (5 lesions), cerebellar hemispheres (3 lesions), brainstem (2 lesions) and cerebral ganglia (1 lesion). 3 cases complicated with cavernous angiomas.T₁WI showed 17 lesions, T₂WI showed 18 lesions, SWI showed 21 lesions. On conventional MRI sequence, the drain vein in 14 cases of cerebral venous malformation revealed blood flow-vacuity signal on T₁WI and T₂WI,hyperintensity or hypointensity on T₁WI and hyperintensity on T₂WI in 3 cases,4 cases were not detected drain vein;most medullary veins were not clealy showed,on T₁WI medullary veins showed iso or hypointensity shaped with point or linear,and iso or hyperintensity on T₂WI. 3 cases associated with cavernous angiomas were showed typical symptom, on T₁WI it appeared as iso or hyperintensity and surround by hypointensity or heterogeneous signal intensity, on T₂WI it appeared as hyperintensity and surround by hypointensity.Dilated medullary veins and gross drain vein in 21 cases cerebral venous malformation were all clearly shown by SWI,and typical"caput medusae"sign was showed. The cavernous angiomas lesions appeared as iso, hyperintensity or heterogeneous signal intensity, surround by hypointensity on SWI, and"ironhoop"sign was showed.Conclusion: SWI sequence has more sensitivity and specificity than conventional MRI sequence in detecting the cerebral venous malformation; the lesions showed more clearly, more small medullary veins might be detected and could diagnose complications of cerebral venous malformation.Part 3 The Application of Susceptibility Weighted Imaging in Diagnosis of Cerebral MicrobleedsObjective: To compare conventional MRI sequences images with susceptibility weighted imaging performance of cerebral microbleeds, and study the diagnostic and clinic value of susceptibility weighted imaging in cerebral microbleeds.Methods: 60 cases cerebral microbleeds were collected and analysed. All of the patients were scaned with axial, sagittal T₁WI, axial T₂WI and SWI. SWI sequence was compared with the conventional MRI sequences in detecting and diagnosing cerebral microbleeds. The statistics of the above results were got by means of Chi-square test to compare whether T₁WI, T₂WI and SWI were different in the detection rate of cerebral microbleeds. Value the superiority of the SWI in showing the cerebral microbleeds.Results: In 60 cases there were only one lesion in 17cases, multiple lesions in 43 cases, 591 lesions were detected, cerebral microbleeds mainly located at cortex or subcortex (40 lesions), basalganglia region (28 lesions),cerebral ganglia (21 lesion) , brainstem (16 lesions) and cerebellar hemispheres (6 lesions). On T₁WI sequences there were 242. On T₂WI sequences there were 318 lesions. On SWI sequences there were 591 lesions. The lesions showed dot or round hypo-intensity signal on SWI. The range of the lesions was larger than that in conventional sequences. The detection rate of cerebral microbleeds on T1WI, T2WI and SWI were compared,χ²=500.521,P<0.001(P<0.05).There were significant difference on the cerebral microbleeds detection rate on SWI and conventional MRI sequences.Conclusion: SWI sequence has more sensitivity than conventional sequences in detecting the cerebral microbleeds.