Study Of Perfusion Scan And Postprocessing Technique In Pate Vessels With 64 Slice CT And Its Application In Cerebral Haemodynamic Measurement In Health Adults

PART 1 STUDY OF THE COMBINATION SCANNING TECHNIQUE OF CEREBRAL PERFUSION AND ANGIO- GRAPHY OF PATE WITH 64 SLICE CTObjective: To discuss the combination scanning technique of cerebral perfusion and angiography of pate with multislice CT.Methods: 84 cases after brain enhanced scan and angiography of brain and cervical part without any abnormality found were selected, 20 cases of brain enhanced scan, 32 of cerebral angiography, 32 of cervical angiography. For 20 cases of brain enhanced scan, 30ml contrast media(ultravist 370 mgI/ml) were injected at the rate of 4ml/s, followed with 15 ml saline as Test-bolus scan to get the Time-density curve(TDC). And 70 ml contrast media were injected at the same rate, followed with 30 ml saline to get another Time-density curve. The two curves were compared. For 64 cases of cerebral or cervical angiography, 20ml contrast media(ultravist 370 mgI/ml) were injected at the rate of 4ml/s, followed with 15 ml saline as Test-bolus scan to compute the peak time of cerebral or cervical vessels.Results: The difference of peak time after injection of small and large dose of contrast media was 8 seconds in patients of brain enhanced scan. The peak time of cerebral arteries was 19.6±2.6 seconds, that of cerebral veins was 25.7±3.2 seconds; that of cervical arteries was 19±2.8 seconds, that of cervical veins was 26.6±3.1 seconds. The difference of peak time of cerebral and cervical arteries was 0.6 second, that of cerebral arteries and veins was 6.1 seconds, that of cervical arteries and veins was 7.6 seconds.Conlusions: CTP-CTA combination scan is to estimate the peak time after injection of large dose by small dose in perfusion scan, and the delay time of large dose angiography is the peak time of small dose plus 8 seconds. There is no significant difference in the peak time between brain and cervical part, so monitoring any peak time of cerebral or cervical vessels is suitable for the combination scanning of pate. The delay time compared with the arteries is about 6 seconds for the pate venography scanning.PART 2 POSTPROCESING TECHNIQUE IN CEREBRAL PERFUSION AND PATE ANGIOGRAPHY WITH MULTISLICE CTObjective: To discuss postprocesing technique in cerebral perfusion and pate angiography with multislice CT.Methods: 65 cases, 35 of health adults and 30 of abnormal patients, were selected to carry out cerebral CT perfusion, with the hibateral anterior cerebral arteries, middle cerebral arteries and internal carotid arteries as input artery, the superior sagittal sinus as output vein. For the health adults, the perfusion parameters were measured in the unilateral cerebral grey and white matter, basal ganglia; for the patients with obvious infarction, the perfusion parameters were measured in the infarction area and in the ipsolateral normal cerebral grey and white matter.Results: According to CT perfusion postprocessing images, there was no significant difference in the perfusion parameters between cerebral grey and white matter, basal ganglia in 35 health adults with the hibateral anterior cerebral arteries, middle cerebral arteries and internal carotid arteries as input artery. So was there in the he perfusion parameters between the normal cerebral grey, white matter and the infarction in 30 patient with obvious infarction but no obvious arterious stenosis, whose input artery were different and output vein was the superior sagittal sinus.Conclusions: In the post-processing of perfusion images, any larger artery in the health adults can be selected as input artery, so can the larger artery in the patients with abnormal perfusion but without obvious vascular stenosis. For the patients with obvious stenosis in the unilateral larger artery, the normal anterior cerebral artery should be tried to select as input artery. It is necessary for postprocessing of pate vessels to have an intimate knowledge and combine the advantages and disadvantages of each postprocesing technique, in order to better display the abnormal vessels and try not to miss any abnormality.PART3 QUANTITATIVE STUDY OF THE CEREBRAL HEMODYNAMICS BY USING MULTISLICE CT PERFUSION IMAGING IN NORMAL ADULTObjective:To explore the application value of multislice CT perfusion imaging in normal adult cerebral hemodynamics.Methods:Routine CT and multislice CT perfusion imaging were performed by selecting the basal ganglia slice and its adjacent slice in 35 normal adults, These scan dynamic images were peocessed with the CT perfusion software package. CBF,CBV and MTT were measured within the specific ROI of the brain,and quantitative analysis was performed. Results:A gradient of perfusion between gray matter and white matter showed on multislice CT perfusion imaging in normal adults.CBF,CBV,MTT were (52.4±11.7)ml/(100g﹒min),(2.7±0.6)ml/100g,(3.7±1.0)s respedtively in the gray matter and (22.3±3.8) ml/(100g﹒ min),(1.4±0.4)ml/100g,(5.1±1.3)s respectively in the white matter.Conclusion:Multislice CT perfusion imaging provided a new imaging method for measuring the cerebral hemodynamics.