Progression Of Small Artery Technique On MRI And Application On Spine,Vertebral Column

PartⅠStudy of improvement on MRA of small artery's techniquesObject To study MRA of small vessel's techniques including repeat time(TR),echo time(TE),receive bandwith(Bandwith),flip angle(FA),K-space type and adjust the best way of injection of contrast material(including the total dose,injection's speed and the delay time).Getting the best imaging of small vessel for the next stepMaterial and methods We placed the small vessel without magnetic which diameters 6.0mm-0.13mm filled with the contrast material(15mmol/L) on the special tissue(1%protein agar) in order to show it on magnetic resonance imaging;10 healthy volunteers was engaged in clinical study and parted in two groups randomly and one group contents 5 volunteers.4 MR scanning was proceeded in every volunteer and the injection's speed was 0.3ml/s,1.0ml/s,2.0ml/s,3.0ml/s respectively.The dose of GroupⅠwas 15ml, the dose of groupⅡwas 30ml.In scanning the peak enhancement and duration time of aorta,portal vein,inferior caval vein was measured.Result Small vessel which the diameter from 6.0mm to 0.51mm was shown clearly.SNR was the highest and the imaging was best when flip angle in 20-25 under the condition of other parameter was fixed.Phase and FOV was more effect than other parameter on total time and imaging qualities.There was no significant statistics means on enhancement of aorta's peak between the single dose and the double dose.When the speed was higher than 1ml/s,there was no significant enhancement on aorta and peak time was no more short.In the test of vein,there was no relation between the peak time and injection speed when the speed was more higher than 1ml/s.Enhancement peak on aorta was increased,however SNR of portal vein and inferior caval vein was not changed.Conclusion In 3D-SPGR technique the resolution was 0.5mm.Parameter was confirmed by 3 ways based on target small vessel.1.contrast should be depend on TR and TE times.2.phase and NEX was set in aortal time phase.3.slice thickness,slip and FOV was the important role to adjust the quality of imaging.When the injection speed was 3ml/s and the dose was 0.2mmol/kg,the SNR of aorta was best and influence of vein was the smallest.PartⅡMR angiography of Adamkiewicz arteryObjective To prospectively investigate the feasibility of contrast material-enhanced magnetic resonance angiography(CE-MRA) for visualization of the spinal vasculature and to assess the spinal vasculature for diagnosis and treatment of spinal surgery.Methods Ten volunteers and fifteen patients with a thoracic herniated disk or lumbar herniated disk underwent contrast-enhanced MR angiography of the thoracoabdominal aorta and posterior branches.Examination was performed with three-dimensional contrast-enhanced MR angiographic technique and 0.3 mmol/kg of gadolinium contrast agent.K-space was ellipse padding.Imaging of MRA was processed by software of maxium intensity projection(MIP) and Reformat.Result In all examinations,time which contrast reached the target vessel was 12-18 seconds The Adamkiewicz,the ASA,and the connection with the aorta were identified. The Adamkiewicz originated between T9 and L2 in all examination and derived from the left side of the aorta in 80%of all examination.ASA was observed from T6 to L2.The diameter of Adamkiewicz was 0.6-1.2mm and ASA was 0.6-1.0mm.Conclusion Contrast-enhanced MR angiography can be used to localize Adamkiewicz and provide accurate information for clinical approach. PartⅢCorrelation Between Diffusion in Lumbar Intervertebral Disks and Lumbar Artery StatusObjective To evaluate the correlation of the lumbar artery status with the diffusion values in lumbar vertebral disks in patients with low back problems using MRA technique and provide helpful information for diagnosis and treatment.Material and methods MR angiography in evaluating the status of lumbar arteries was calculated.Then,The sagittal diffusion-weighted MRimages in 260 intervertebral disks(L1-2 to L4-5) and MR angiographic images in the corresponding 260 lumbar artery pairs(total of 520 arteries) of the 65 patients with low back problems.65 patients.(39 men,26 women;mean age 52.3 years;age range 16-76 years) were included in the present study.Low back pain with sciatica was found in 11, low back pain without sciatica in 16,sciatica without low back pain in 33,and intermittent claudication in five patients.The time interval from onset of clinical symptoms to MR examination was 1 - 57 weeks(mean 13.4 weeks).10 volunteers was proceed MRA examination.(age range 22-43,mean age 29.4).They were not been found with low back pain.Result lumbar artery of L 1-4 was well showed.There was statistics means between the degradation of lumbar disc and its ADC.(p＜0.05).There was positive relation between artery status of L1,L2,L3 and lumbar disc of L1-2,L2-3,L3-4.(F_L1-L2=25.982,P _L1-L2=0.017＜0.05;F_L2-L3=23.173,P_L2-L3=0.017＜0.05;F_L3-L4=20.552,P _L3-L4=0.026＜0.05))However there was no positive relation between the artery of L4 and the L4-5 lumbar disc(F_L4-L5=10.982,P_L4-L5=0.125＞0.05).Conclusion ADC value of the L1-2,L2-3,L3-4 can reflect the status of the lumbar artery.There was no significant relation between the L4-5 lumbar disc and the L4 lumbar artery because of the L4 lumbar artery has many small vessel coincided with artery of iliolumbar.