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Objective To evaluate the clinical value of enhanced 3D-SPACE-STIR sequence MR in brachial plexus injury post-ganglionic nerve.Methods Eighteen patients with suspected brachial plexus injury were examined by routine MRI,3D-SPACE-STIR sequence and enhanced scan.The position,morphology,signal intensity of the brachial plexus injury and its relation with the proximal and distal portions of the brachial plexus were evaluated by senior radiologists.The image quality of plain and enhanced 3D-SPACE-STIR was evaluated respectively.Results The CNR of plain scan and enhanced 3D-SPACE-STIR sequence images were 32.31+2.98 and 43.66+2.78 respectively and the difference was statistically significant.Plain and enhanced 3D-SPACE-STIR sequences of supraclavicular nerves display rate were 95.0% and 96.1% respectively without having statistically significant difference.However,the subclavicular segment of the brachial plexus showed the displaying rates of 66.7% and 94.4% and the difference was statistically significant.Moreover, the background suppression effect of enhanced scan was better than that of the plain scan.Conclusion Enhanced 3D-SPACE-STIR sequence can clearly show brachial plexus injury,and its image quality is better than that of the plain scan,which can provide important imaging basis for accurate diagnosis of brachial plexus injury.
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Objective To analyze the imaging features of hepatic angiomyolipoma (HAML) on computed tomography (CT) and magnetic resonance imaging (MRI).Methods The imaging fingdings of 18 tumors which were pathologically diagnosed as HAML after surgery were analyzed retrospectively.Before operation,twelve and ten patients underwent CT and MRI non-contrast and dynamic enhanced scans,respectively,and 4 patients received both examinations.The imaging characteristics including the number,diameter,location,appearance of the lesions,plain and dynamic enhancement mode were analyzed.Results Eighteen HAML lesions were found in 18 patients with a diameter ranging from 1.5 cm to 17.2 cm (mean 5.3 cm).Five lesions manifested fatty content,and one showed hemorrhage and necrosis.Five HAMLs enhanced in a fast-in and fast-out mode,eleven in a fast-in and slow-out mode and two other lesions in an irregularly discrete mode.The arterial supply was found in 11 HAMLs in the hepatic arterial phase,all coming from intrahepatic arteries.Intratumoral vessels were observed in 12 HAMLs.Early draining veins to the hepatic vein (n =3) and portal vein (n =1) were detected in 4 HAMLs.One lesion demonstrated delayed enhancement in the pseudocapsule.Conclusion The detection of arterial supply and intratumoral vessels in a hypervascular hepatic tumor on contrast CT and MRI in a patient with a non-cirrhotic liver and normal AFP helps to make a diagnosis of HAML.
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Objective To evaluate the clinical value of 320-detector CT in interventional treatment of bronchial artery hemoptysis. Methods CTA and DSA images of 30 patients with bronchial artery hemoptysis were retrospectively analyzed.Spatial anatomical characters of the bronchial arteries,such as the type of branches,origin and opening positions of the bronchial arteries were observed and recorded.Results In 30 patients,6 bronchial arteries distribution patterns were found,and the most common type was R1 L1 (43.3%).83 bronchial arteries were identified using CTA,including 38 on the right and 45 on the left.The right bronchial arteries mainly originated from the intercostal artery (52.6%),while the left bronchial arteries mainly from the descending aorta and aortic arch (82.2%).The opening positions of right and left bronchial arteries were mainly located at the right wall of the descending aorta (78.9%),and anterior wall of the descending aorta (62.2%),respectively.When the cacarina of trachea was used as the reference position,the left and right bronchial arteries were mainly located in the range of above 2 cm to below 1 cm from tracheal bifurcation, accounting for 80% and 89.5%,respectively.Compared with DSA,the sensitivity and specificity of CTA were 97.5% and 100%, respectively.Conclusion 320-detector CT can be used to clearly display the distribution patterns,origin and opening positions of bronchial arteries,and especially to find bronchial arteries with ectopic origin.It is possible to apply 320-detector CT in preoperative routine examination and postoperative evaluation of massive hemoptysis.
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Objective To evaluate the feasibility of optimized scan protocol in whole-brain perfusion imaging with 320-MDCT scanner.Methods Twenty healthy volunteers were randomly divided into control group (13 patients) and test group (7 patients).The standard perfusion scan protocol (collecting 19 volumes)was applied in control group.The optimized perfusion CT scan protocol(collecting ll volumes)formulated by reducing scanning phases reasonably and changing the collection intervals was applied in test group.The regions of interest(ROI) with area of(20 ± 2)mm2 were located in the bilateral frontal white matter,parietal white matter,centrum semiovate,basal ganglia,occipital lobe and cerebellum.Bilateral perfusion values from ROI were measured,including cerebral blood volume(CBV),mean transit time (TTP),cerebral blood flow (CBF),mean transit time (MTT) and delay time (DT).Results Dose length product (DLP)and effective dose (ED)in optimized protocol were decreased 42.02％ as compared to control group.Every relative perfusion value of both sides from both groups were not statistically significant (P ＞ 0.05).Every relative perfusion parameters from individual territory in both groups showed no significant differences (P ＞ 0.05).Conclusions Using the optimized scan protocol,we could obtain the same whole-brain perfusion values could be obtained with the default standard protocol and less radiation dose.
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Objective To compare the difference of entrance dose between CR and amorphous silocon DR system in chest imaging, and to discuss their optimum exposure dose. Methods For CR and DR, different entrance dose was measured by dosimeter in chest phantom. The value of IQFinv was analyzed by CDRAD2. 0 software. Image quality difference between CR and DR was assessed by group t-test. The relationship between image quality and entrance dose was tested by using Pearson correlation analysis. The best IQFinv values in CR and DR system were achieved via ROC curve analysis, and the exposure dose was then calculated. Results There were direct correlation values between entrance dose and the value of IQFinv in CR and DR system, respectively( r =0. 893 ,0. 848 ,P < 0. 01 ) . The linear regression equation for DR was IQFinv =0. 0050 +3. 359, and for CR was IQFinv =0. 005D + I. 651 , where D was entrance dose. The difference of IQFinv value between CR and DR was significant(t = 5. 455 ,P < 0. 05). The best IQFinv value of the two groups from ROC analysis was 3.55. Conclusions With the entrance dose increased, the detection ability of contrast-detail was elevated in the two digital radiography systems. With equal entrance dose, the detection ability of DR in contrast-detail was superior to CR. With equal image quality, DR obviously decreased the radiation dose to the patients.
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Objective 7 cases of thoracic spinal cord injury without radiographic abnormality (SCIWORA) were analyzed to elevate the level of diagnosis and treatment.Methods The type of spinal cord injury were classified into complete injury in 2 and incomplete injury in 5 according to Frankel. 5 cases had MRI examination. Conservative therapy was adopted in 5, and operation was programmed in 2.Results 4 cases recovered completely , 2 cases recovered partly , and 1 case had no recovery.Conclusion MRI provides reliable foundation for diagnosis and treatment to thoracic SCIWORA. The result is satisfactory in those incomplete injury.