An Fundational And Clinical Study Of Orbital Tumor With New MRI Technique

Part 1: The diagnosis of orbital tumor with dynamic contrast-enhanced MRIPurpose: To analysis the characteristics of eye diseases with before and after dynamic contrast-enhanced MR images, improve the ability of diagnosis and different diagnosis of eye diseases, especial benign and malignant tumour. Materials and Methods: 1 -, total 41 cases had been trained by MR .examination, including 31 benign tumors and 10 malignant tumor. 2. MR examination: Using Magneton Vision Plus 1.5T MR system. MR images had been obtained from Tl WI and T2WI turbo-SE sequence include with sagittal, transverse and coronal sections, before, after and dynamic contrast-enhanced period. 3. To analysis characteristics of lesions enhancement, including: enhancement rates(E%) should be quantified by ROI-based signal intensity measurements. To accout for differences in baseline tissue Tl relaxation times, enhancement rate is calculated as signal intensity increase relative to baseline values: E%=(SIpost-SIpre)/SIprex100%. The enhancement kinetics in the intermediate and late post-contrast period had be evaluated by means of time/signal intensity course(TIC).Three of signal intensitycurve; Tpye 3 is a wash-out time course. Results:1) The enhancement rate(first post-contrast minute) is higher than 60% in malignant tumor, meanwhile lower than 60% in benign ones(P<0.05).2) Type 1 time course is indicative of most of benign tumor except meningioma, whereas type 3(wash-out) strongly supports infectious diseases and type 2 malignant tumor.3) There are special enhanced model in Cavernous hemangiomas. Conclusions:1) Dynamic contrast-enhanced MRI is a valuable method to distinguish malignant tumors between benign tumors, tumors between infectious diseases.2) Typical manifestations of Cavernous hemengioma were found by Dynamic contrast-enhanced MRI.Part 2 The clinical and fundamental application of 1HMRSpectroscopy in orbital diseasesPurposes: 1) To investigate the clinical application of proton magnetic resonance spectroscopy (1HMRS) in orbital tumors; 2) To study character of 1HNMR spectroscopy (9.395T) of orbital tumors in vitro; 3) To study whether character of 1HNMR spectroscopy of orbital tumors in vitro and character of 1HMRS of orbital tumors in vivo are identical or not. 4) To evaluate the value of 1HMRS forMethods: 1) 40 cases with pathology-proved tumors had been undergone HMRSexaminations. Single-voxel localized 'HMRS were performed in all patientssuspected of tumors on MR images. Depend on corresponding SVS-STEAM270sequence, NAA, Cho, Cr, Ace and Lac were obtained from normal-forehead brainparenchyma in each patient for comparison with the spectra from known area ofpathology at the same side. 2) 12 cases sample of tumors, including 7 benigntumors(5 cases cavernous hemangioma 1 case meningioma 1 case Neurofibroma),3 malignant tumors (1 case hemangiosarcoma 2 case lymphoma), and 1 normalmuscle and 1 optic nerve are measured by 400MHz BRUKER HR/MAS(9.395T). 3) The position, wide, amp and integ of the wave peaks were calculate,and were evaluated the changes of metabolic materials among malignant, benigntumors.Results :1) The position of each metabolites are stable.2)Curve-areas of each metabolites for all orbital tumors was significant difference,between non-tumors.especially,a significant difference existed in curve-areas ofCho, Cr and Cho/Cr between benign and malignant orbital tumors (P<0.05).3) Curve-areas of Lac, Ace of benign tumors is higher than non-tumor tissues andlower than malignant tumors.4)The results showed that clinical 'H MRS and HR/MAS can obtained similarresults for orbital tumors.main detectable metabolites are N-acetyl-aspartate(NAA), choline-containing compounds(Cho), creatine(Cr) ,acetate(Ace)and lactate(Lac). Conclusions:1) The 1HMRS wave style are quite different from orbital tumor and non-tumor tissues.2) The 1HMRS has shown a quite higher level of Cho and Cho/Cr in malignant tumour than which in benign...