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Objective To investigate diagnostic magnetic resonance imaging features of orbital Langerhans cell histocytosis (LCH)and improve its diagnostic accuracy.Methods The symptoms and image data of fourteen histophathology verified orbital LCH cases are reviewed and analyzed.Results Nine patients had swollen eyelids,accompanying with symptoms of inflammation, esphthalmos and orbital masses.One case had cough symptom and another had diabetes insipidus.Of these fourteen cases,seven occurred in right orbital,six occurred in left orbital and one involved bilateral orbital.As to the location of LCH,six cases located in super-lateral wall of the orbit,five cases located in lateral wall of the orbital,and three cases located in roof of orbital.On MRI, thirteen cases lesions show hypo or iso signal intensity on T1 WI,and eleven cases lesions show heterogeneous hyper or iso signal in-tensity on T2 WI.The lesions of eosinophilic granuloma has clear border,which differentiate it from other types.After contrast en-hancement,MR imaging showed marked inhomogeneous enhancement.Conclusion MRI is the primary modality in diagnosing of or-bital LCH,clearly and accurately manifesting the extent of orbital LCH.It will be helpful to diagnose LCH timely if combining with clinical data.MR could provide reliable information for making surgical operation and treatment plan.
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Objective To observe the value of dynamic contrast-enhanced MR angiography (DCE MRA) with gadobenate dimeglumine in evaluation of vascular complications after living donor liver transplantation. Methods Thirty-four consecutive patients were examined with MR after living donor liver transplantation. First, 1 ml gadobenate dimeglumine was injected in vein to infer the time of gadobenate dimeglumine reaching abdominal artery performing testbolus. Then a scan with three-dimensional T1-weighted fast low-angle shot (3D-FLASH) sequence was performed. Four phases in series from arterial period were scanned and every phase paused 10 s to obtain images of the arterial, portal venous and hepatic venous systems. The original and maximum intensity projection (MIP) reconstructed images, categorized vessel visualization on a five-point scale and observed stoma of hepatic artery, portal venous and hepatic venous inferior vena cava, diameter and display of surrounding vessels were observed. The results were compared with those of digital subtraction angiography (DSA), ultrasound and clinical data. Results Overall vessel visualization assessment demonstrated good or very good ratings for the majority of patients. Among all 34 patients, hepatic artery stenosis was found in 4, portal vein stenosis in 6, portal vein thrombosis was detected in 2, while middle hepatic veins stenosis was detected in 1 patient, among whom 10 patients were confirmed with DSA, 4 with surgery, the others with ultrasound or follow-up. Conclusion Gadobenate dimeglumine DCE MRA is a highly accurate, noninvasive tool for evaluation of vascular complications after living donor liver transplantation, may be regarded as the first choice in postoperative evaluation.
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Objective To explore whether dynamic contrast-enhanced MRA (DCE MRA) can provide an effective assessment of renal vascular in living donors before transplantation.Methods Thirty five healthy living renal donor candidates were scanned on MR system before transplantation.After injection of Gd-DTPA 1 ml in vein, a test-bolus scan was used to get the time delay of Gd-DTPA reaching renal artery.Then, a 3D T1-weighted fast low-angle shot sequence (3D FLASH) was performed in the coronal plane.The 3D FLASH scan would repeat four times with an inter-phase of 10 seconds.Thus, the imaging of the renal arterial, venous and collecting systems were got.Two radiologists observed renal arteries and veins on original imaging and MIP reconstructed imaging.The quality of MR angiography was evaluated on a fivepoint scale and the vascular anatomy or variations of the arterial and venous systems were recorded, using intraoperative findings as a standard of reference.Results The quality for all MRA was good or very good for the most of living renal donors.Among 70 renals, several variations of vascular were found, including 5 left accessory artery, 9 right accessory artery, 3 left proximal arterial branch and 6 right proximal arterial branch.Among 70 renal veins, 1 right accessory veins and 2 left varieocele were observed.One small accessory artery of right kidney was missed with DCE MRA, but identified by operation.Conclusion DCE MRA was noninvasive tool for evaluation of the renal vasculature and variations with high accuracy.It would be a good modality in preoperative evaluation of living renal donors.
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Objective To investigate the feasibility of measuring liver volume with Argus methoct Methods Thirty-two healthy liver transplant donor candidates underwent liver MRI on a 3.0 T MR unit.Volume interpolated body examination(VIBE)was performed after the administration of gadobenate dimeglumine.The VIBE data was transferred to the diagnostic workstation,and then multiple planar reconstruction(MPR)images were acquired.Firstly.two observers manually drawn the liver shape and calculated three volumes:the whole liver volume and right lobes volumes include middle hepatic vein (MHV)and exclude MHV,respectively.Secondly,the same data was transferred to Argus software.calculated that three volumes.Each measurement time was recorded.Actual graft volume(the right lobe)wag measured during surgery.The correlation between right lobes volume of two measurements and actual graft volume was analyzed.The time needed for Argus and that needed for manual method were compared with paired t test.Results The right lobe volumes measured by Argus,manually and surgery method were (813±187),(807 ± 181)and(713 ± 137)mm3,respectively.Argus method and manual method showed good correlation with surgery method,and the correlation coefficients were 0.897(Argus method)and 0.884(manual method),respectively.The time for manual method and Argu8 method were(44.3 ±2.7)and(12.2.±1.0)min,respectively.There was significant difference between Argus and manual methods (t=76.39,P＜0.05).Conclusion Compared with manual method,use of the Liver volumetric measurement by Argus software not only correlated well with Actual graft volume,but also saves time.Argus has potential clinical value for volumetric measurement in living liver transplant donors.
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Objective To compare conventional T2-weighted MR cholangiography (T2WI-MRC) with gadobenate dimeglumine enhanced T1-weighted MR cholangiography(CE-MRC) for evalution of biliary anatomy in liver transplant donor candidates. Methods Thirty-two healthy liver transplant donor candidates were examined with two MR cholangiogaphic methods. For T2WI-MRC, a three-dimensional turbo spin-echo sequence and oblique coronal heavily T2-weighted thick-slab turbo spin-echo imaging sequence were performed. For CE-MRC, three-dimensional fat-suppressed spoiled gradient-echo sequences were performed, with a time delay of 60 minutes following the administration of gadobenate dimeglumine. To compare the depiction of biliary duct anatomy and the artifact caused by intestinal liquid and breathing between the two methods. Intraoperative cholangiography was the reference-standard examination. Results The both methods depicted the biliary anatomy correctly in all 9 cases. The both methods showed the third branches of intrahepatic biliary duct clearly. T2WI-MRC showed interhepatic bihary duct before the third branches in 28 cases (87.5%), CE-MRC showed the same finding in 14 cases (43.8% ). T2WI-MRC showed common bile ducts intermitantly in 2 cases, which were normal in CE-MRC and intraoperative cholangiography. Intestinal liquid affected the image quality of biliary duct in 6 cases (18.8%) performed with T2WI-MRC, but none with CE-MRC. The artifacts caused by breathing were not obvious in the either method. Conclusion T2WI-MRC and CE-MRC both can be used to evaluate bihary anatomy of liver transplant donor candidates, but CE-MRC appears to be more accurate than T2WI-MRC.