To investigate the sensitivity of chemoradiotherapy on nasopharyngeal carcinoma using intravoxel incoherent motion MRI / 中华放射学杂志

Objective To investigate the application value of intravoxel incoherent motion (IVIM) MRI for evaluating the sensitivity of chemoradiotherapy on nasopharyngeal carcinoma (NPC). Methods Sixty eight consecutive patients newly diagnosed with NPC in the stage of T3 (30 patients) or T4 (38 patients) were retrospectively enrolled. They were divided into effective group (45 patients) and poor?effective group (23 patients) clinically after a standard chemoradiotherapy according to the RECIST criteria. IVIM with 13 b?values (range,0 to 800 s/mm2) and general MRI were performed at 3.0 T MR scanner before and after chemoradiotherapy. Two radiologists major in MRI diagnose analyzed all images independently and placed regions of interest (ROIs). Intraclass correlation coefficient (ICC) was used to evaluate intra?observer and inter?observer agreement. And Mann?Whitney test was used to assess the differences between the two groups. Results The reproducibility between intra?observer and inter?observer was relatively good. Statistically,D [(0.69±0.06)×10?3 mm2/s vs. (0.52±0.10)×10?3 mm2/s; U=51.5,P<0.01)] and D* [(161.33 ± 11.50)×10-3 mm2/s vs. (126.96 ± 10.27)×10-3 mm2/s; U=18.0, P<0.01] were significantly higher in effective group than those in poor?effective group, whereas the difference of f (16.68 ± 1.94% vs. 16.40±1.11%, U=434.5, P=0.282) and ADC (1.23±0.11)×10?3 mm2/s vs. (1.25±0.10)×10?3 mm2/s,U=427.0,P=0.240) could not reach statistical significance between the 2 groups (P>0.05). Conclusions IVIM may be potentially useful in assessing the chemoradiotherapy on NPC. The higher D value combined with higher D*value might indicate the chemoradiotherapy on NPC is more sensitive,and the higher D*value might reflect increased blood vessel generation and parenchymal perfusion in NPC.

Development and validation of a multivariate risk model for distant metastasis of advanced nasopharyngeal carcinoma / 南方医科大学学报

OBJECTIVE@#To develop a model based on the clinical variables for evaluating the risk of distant metastasis in patients with advanced nasopharyngeal carcinoma (NPC).@*METHODS@#From September,2007 to June,2015,a total of 238 consecutive patients with biopsy-proven NPC in stage Ⅲ-Ⅳ(M0) based on the AJCC TNM staging manual were enrolled in this study,including 106 male and 34 female patients with a median age of 45 years (range 18-68 years).In this cohort,126 patients received concurrent chemoradiotherapy,and 24 received chemotherapy and radiotherapy,and 40 had induction chemotherapy.We used the least absolute shrinkage and selection operator (LASSO) method to select the most significant features for establishing the model for assessing the risks of distant metastasis.@*RESULTS@#Among the 18 clinical variables tested,5 were significantly associated with distant metastasis in advanced NPC,including plasma Epstein-Barr virus (EBV) DNA,neutrophil/lymphocytes (NLR),VCA-IgA,concurrent chemoradiotherapy,and induction chemotherapy.Based on these 5 clinical variables,we established the following model:risk score=1.73×EBV DNA+0.54×NLR+0.38×VCA-IgA-0.95×concurrent chemoradiotherapy-2.37×induction chemotherapy+0.51.The cutoff point of this model was-0.62,which classified the patients into high-risk and low-risk groups for distant metastasis.This model showed a good performance in predicting distant metastasis in patients with advanced NPC (<0.01).@*CONCLUSIONS@#The model we established herein can be used for evaluating the risks of distant metastasis in patients with advanced NPC and provides assistance in the clinical decision-making on individualized treatment strategy.

Analysis of CT and MRI signs of hepatic eosinophilic infiltration / 中华放射学杂志

Objective To study and analyze the CT and MRI findings of hepatic eosinophilic infiltration. Methods Twenty nine patients of hepatic eosinophilic infiltration who were confirmed by biopsy or clinical diagnosis were retrospectively analyzed. All the patients underwent CT and/or MRI scan. Twenty seven cases underwent upper abdominal CT plain scan and three phase enhanced scan, and 5 cases underwent upper abdominal MR plain scan and three phase enhanced scan, of which 3 cases underwent CT and MRI scan. Evaluations were made regarding to the numbers of lesion, distribution, size, shape, margin, density or signal characteristic, enhancement parttern and other special features. Pearson correlation analysis was used to analyze the correlation between the number of hepatic lesions and the number of eosinophils in peripheral blood. Results A total of 108 lesions of eosinophilic hepatic infiltration were observed in 29 cases, including 2 cases with single lesion and 27 cases with multiple lesions. Ninety five of the lesions were located in subcapsular parenchyma or surrounding the portal vein. Most subcapsular lesions were wedge-shaped(n=28). Lesions surrounding portal vein were round-shaped(n=32), while the hepatic parenchymal lesions were irregular or round-shaped(n=13). The mean size of lesion was 34 mm, ranging from 3 to 61 mm. The margin of all the lesions were obscure. The lesions showed slightly low density or isodensity on CT pre-contrast images. On MR pre-contrast images, lesions showed slightly low signal or isointense on T1WI, and hyperintense on T2WI. Branches of portal vein were found infilrated by all lesions. Tueleve cases showed“stripe sign”along the portal vein branches, 16 cases showed“halo ring sign”around the portal vein. Pearson analysis indicated a significant correlation between the number of eosinophilic hepatic infiltrated lesions and the increase of eosinophils in peripheral blood (r=0.783, P<0.05). Conclusion The imaging features of EHI had certain characteristics, especially in the three phase dynamic enhanced scanning, from which we can mainly find“progressive enhancement”,“portal vein sign”,“stripe sign”and“halo ring sign”.

Development of preprocedure nomogram for predicting contrast-induced acute kidney injury after coronary angiography or percutaneous coronary intervention / 中国介入影像与治疗学

Objective To establish a preprocedure nomogram for predicting contrast-induced acute kidney injury (CI-AKI) after coronary angiography (CAG) or percutaneous coronary intervention (PCI).Methods Clinical data of 245 patients underwent CAG or PCI were collected.CI-AKI prediction nomogram integrated preprocedural predictors was established with clinical characteristics associated with CI-AKI which were selected with the LASSO regression model,and CI-AKI risk scores were calculated.The ROC curve was constructed to calculate the risk score cutoff.Results The occurrency of CI-AKI was 13.88％ (34/245).Sex,diabetes mellitus,lactate dehydrogenase level,high-sensitivity C-reactive protein,drinking years,chronic kidney disease (CKD),stage of CKD,stroke,acute myocardial infarction as well as systolic blood pressure were significant risk factors.The efficiency of CI-AKI nomogram was good,and the cutoff value of risk score was-1.953.Conclusion The novel nomogram can be used to preprocedurally predict the risk of CI-AKI after CAG or PCI treatment.

Value of modified Killian′s method in diagnosis of congenital pyriform sinus fistula / 中华耳鼻咽喉头颈外科杂志

Objective@#To investigate the feasibility and significance of modified Killian(MK) method in the clinical diagnosis of congenital pyriform sinus fistula(CPSF) by electronic laryngoscopy.@*Methods@#The following examinations were performed for 30 suspected cases of CPSF, including the traditional electronic laryngoscopy, MK examination(modified Killian position+ head rotation+ the Valsalva maneuver), barium swallow X-ray(BSX) and CT , and a prospective comparison among them were done. Patients were divided into two groups according to their age: young age group(≤14 years old) and older age group (>14 years old). The results of MK examination from the patients were analyzed and the positive diagnostic rates (PDR) between groups were compared by using χ2 tests.@*Results@#Sinuses in 20 of 30 patients were depicted from pyriform sinus in BSX, and the PDR was 66.7%(20/30). The PRD of CT was 83.3%(25/30). The presence of air bubbles around the upper lobe of the thyroid gland or at the inferomedial edge of cricothyroid joints, morphological changes of thyroid grand as well as pseudo-fistula formation on lower neck were detected clearly on CT. Comparing to the traditional electronic laryngoscopy, the effect of exposing piriform fossa fistula by MK examination is significant(χ2=17.05, P<0.05), with the PDR of 13.3%(4/30) and 76.7%(23/30) respectively. Nevertheless, comparing to BSX and CT, there were no statistically significant differences in the effect to diagnose CPSF (χ2=0.31, χ2=0.10 respectively, P>0.05). The PDR of MK in older group is significantly higher than younger group(χ2=6.68, P<0.05).@*Conclusions@#MK examination can clearly reveal the hypopharyngeal anatomical structure and detect the sinus of CPSF .It could be a safe, feasible, convenient and economical method as an application in preoperative diagnosis and follow-up examination of clinical suspected CPSF.

The long-term clinical efficacy of endoscopic surgery of primary sinonasal malignant neoplasms / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To assess the long-term clinical efficacy of endoscopic surgery of primary sinonasal malignant neoplasms and find out the potential postoperative prognostic factors.@*METHOD@#Forty-three clinical cases of primary sinonasal malignant neoplasms treated under endoscopy were analyzed retrospectively.@*RESULT@#Fifteen patients died. The 1-year, 2-year, 3-year and 5-year survival rates were 83. 7% (36/43), 74. 4% (32/43), 69. 8% (30/43) and 65. 1% (28/43), respectively. Kaplan-Meier single-variable analysis showed that gender, T grade, TNM stage and pathological types of olfactory neuroblastoma were statistically significant prognostic factors (P< 0. 05). COX Pro-Portional hazard models showed that TNM stage was an independent prognostic factors.@*CONCLUSION@#Endoscopic surgery for primary sinonasal malignant neoplasms is a safe and effective minimally invasive surgical treatment, and it is an important supplement to the traditional surgery. Gender, T grade, TNM stage and pathological types of olfactory neuroblastoma might be significant prognostic factors.

Resting-state functional magnetic resonance imaging of first-onset major depressive disorder: analysis of 18 cases / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the changes in brain regional homogeneity in first-onset major depressive disorders (MDDs) using resting-state functional magnetic resonance imaging (fMRI).</p><p><b>METHODS</b>Eighteen patients with first-onset MDDs and twenty gender- and age-matched healthy controls underwent resting-state fMRI scans to compare the regional homogeneities of the brain regions.</p><p><b>RESULTS</b>Compared with the normal controls, the patients with MDDs showed significantly decreased regional homogeneity in the left posterior cingulated gyrus, bilateral inferior temporal gyrus, bilateral superior temporal gyrus, left inferior frontal gyrus, left hippocampa gyrus, left posterior central gyrus, left angular gyrus, right amygdala, right orbital frontal gyrus, right supplementary motor area, and right cerebellar lobe.</p><p><b>CONCLUSION</b>Patients with first-onset MDDs have dysfunctions in the brain regions closed related with cognition and emotional control.</p>

The treatment of diabetes mellitus complicated acute necrotizing sinusitis / 重庆医学

Objective To investigate the treatment of diabetes mellitus complicated acute necrotizing sinusitis .Methods By way of reviewing the clinical procedures of 2 patients with diabetes mellitus complicated acute necrotizing sinusitis .Results In perioper-ative period ,by means of glycemic control ,anti-infection ,and emergency surgery to remove the necrotic tissue in nasal sinuses and open the sinuses ,one of the patients discharged from hospital after 8 days .He has been followed up for more than 4 years without recurrence ,and is still in follow-up .Due to complicating renal failure and ascites ,the another patient gave up treatment and dis-charged on the third postoperative day ,and died on the same day .Conclusion Glycemic control ,homeostasis ,surgical removal of necrotic tissue and anti-infection treatment in perioperative period as soon as possible ,is the key to a successful treatment .

Trans-sphenoid sinus-clivus endoscopic management of petrous apex cholesterol granuloma / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To explore the endoscopic management of petrous apex cholesterol granuloma through trans-sphenoid sinus-clivus approach.@*METHOD@#One case of right-side petrous apex cholesterol granuloma were undertaken surgical treatment through trans-sphenoid sinus-clivus approach, then the possibility of any other approach and their advantages and disadvantages were analyzed.@*RESULT@#The operation was success without any complications. Patient's hearing was recovered and tinnitus vanished. The patient was discharge from hospital at the third day after operation, and followed up for four month without recurrence.@*CONCLUSION@#Trans-sphenoid sinus clivus endoscopic management of petrous apex cholesterol granuloma is effective and safe. The operators can monitor internal carotid artery then to access to the diseased region with reducing risk.

Intravoxel incoherent motion diffusion-weighted imaging in differential diagnosis of primary nasopharyngeal carcinoma and nasopharyngeal hyperplasia / 中华放射学杂志

Objective To investigate the feasibility of diffusion-weighted(DWI) MRI on basis of the intravoxel incoherent motion (IVIM) in nasopharyngeal carcinoma (NPC),and the diagnostic value of pure molecular diffusion coefficient (D),perfusion-related diffusion coefficient (D *) and perfusion fraction (f) in first onset NPC.Methods From December 2011 to January 2013,40 consecutive patients (26 men,14 women; median age,52 years) with suspected NPC were examined on a 3.0 T MR scanner.DW imaging was performed by using a single-shot echo-planar sequence with 13 b-values (0,10,20,30,50,80,100,150,200,300,400,600,800 s/mm2).MR imaging was compared with endoscopy and biopsy for the detection of NPC.Mean interval time between MR imaging examination and subsequent nasopharyngeal biopsy was 3 days (range,0-11 days).The subjects were divided into 2 groups according to the pathological results,group A was subjects with NPC (17 men,9 women; median age,35) and group B was ones with nasopharyngeal chronic hyperplastic inflammation(NPH) (9 men,5 women; median age,35).The D,D * and f were measured and compared in patients with first onset NPC and nasopharyngeal hyperplasia (Mann-Whitney test).Results IVIM DWI was successful in 24/26 with NPC and 12/14 with NPH.D value was significantly lower in A group compared with B group [mean,(0.70 ± 0.13) ×10-3 mm2/s vs (0.78 ± 0.05) × 10-3 mm2/s ; U =2.05,P ＜ 0.05],as was f value [mean,(16.25 ±1.46) ％ vs (26.20 ± 3.90) ％ ; U =11.16,P ＜ 0.01].However,D* value was significantly higher in Agroupas compared with B group[mean,(161.8 ±23.56) × 10-3 mm2/s vs (55.28 ± 17.05) × 10-3 mm2/s; U =13.90,P ＜0.01].Conclusions IVIM DWI is a feasible technique for investigating first onset NPC and D value has a certain value in differentiating NPC and NPH.D* value has an important potential value in distinguishing benign and malignant NPC.

Clinical application value of 3.0 T MR susceptibility weighted imaging in diagnosis of neonatal hypoxic ischemic encephalopathy / 临床儿科杂志

Objective To evaluate the clinical application value of susceptibility weighted imaging (SWI) in neonatal hy-poxic ischemic encephalopathy (HIE). Methods Thirty-six neonates with HIE were collected and scanned by GE 3.0 T supercon-ducting MR scanner. Routine axial T1WI, T2WI, FLAIR scan and axial SWI scan were conducted. SWI sequence was compared with conventional head MRI sequences in detection rate of distribution and quantity of intracranial hemorrhage. Meanwhile, the display condition of the dilated cerebral deep veins and cortical veins was observed on SWI image and the performance of HIE in different clinical classification on SWI was compared. Results A total of 97 intracranial hemorrhages were detected by SWI in 27 cases. Only 41, 27 and 51 hemorrhages were found by TIWI, T2WI and FLAIR sequences, respectively. SWI were significantly superior to T1WI, T2WI and FLAIR in displaying the size, scope and boundary definition of hemorrhage. A total of 50 dilated ce-rebral deep veins and cortical veins were detected by SWI in 22 cases which were not found by conventional head sequences. The detection rates of intracranial hemorrhage and intracranial hemorrhage in addition of dilated cerebral veins on SWI sequence were the lowest in mild HIE group, and highest in severe group. There was significant difference among the mild, medium and severe groups (P<0.05). Conclusions SWI sequence has higher sensitivity than conventional MRI sequence in detecting intracranial hemorrhage and dilated vein in HIE, and is useful for early diagnosis of HIE.

CT evaluation of benign and malignant solitary fibrous tumor of the pleura / 中华放射学杂志

Objective To analyze CT findings of solitary fibrous tumors of the pleura (SFTP) for differentiating benign and malignant lesions.Methods CT findings of 20 benign and 11 malignant SFTPs proved by pathology were retrospectively reviewed. The size,margin,internal structures,blood supplies,invasion to adjacent structures or metastasis and pleural effusion were analyzed and compared between malignant and benign groups.Results The mean diameter of malignant lesions( median diameter:13.5 cm) was larger than that of the benign ( median diameter:7.6 cm,F =6.411,P =0.017 ).Malignant lesions tended to be more heterogeneous (9/11,P =0.002),more invasive to adjacent structures ( 6/11,P =0.001 ) than benign lesions ( 4/20,0/20 ).Serpiginous vessels ( 10/11,P =0.008 ) and pleural effusion (6/11,P =0.038 )were more common in malignant lesions than those in benign lesions (8/20,3/20).Calcification could be found in both benign (2/20) and malignant lesions ( 2/11,P =0.6 ).Furthermore,3D CT angiography could show blood supplies into tumor in 12 lesions (4 benign and 8 malignant SFTPs).Conclusion CT and 3D CTA are helpful in differentiating benign from malignant SFTPs and evaluating the excision of SFTPs.

Quantitative study of rabbit hepatic ischemia reperfusion injury with apparent diffusion coefficient values: comparison with pathology and biochemistry / 中华放射学杂志

Objective To explore the value of DWI ADC in the diagnosis of hepatic ischemia reperfusion injury (IRI) at 3.0 T and investigate the mechanism by comparison with liver enzyme and pathological findings. MethodsForty-two New Zealand white rabbits were divided randomly into ( n ＝ 6,each) six IRI groups by rank sum test. The IRI animals underwent left lobar ischemia for 60 min and were reperfused 0. 5 h, 2. 0 h, 6. 0 h, 12. 0 h, 24. 0 h and 48. 0 h later. One Sham operative group underwent laparotomy without liver ischemia. T2 WI, T1 WI, DWI and contrast-enhanced T, WI were performed with 3.0 T magnetic resonance imaging scanner in each group respectively. For DWI, b-values of 20, 50, 100,200,300,400,500 and 600 s/mm2 were used respectively. Blood samples were taken to detect the levels of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) at different time points. Liver samples were examined histologically after MRI scanning. One-way analysis of variance (ANOVA) was used to determine differences, followed by LSD-t test for multiple comparisons. ResultsOverall, ADC decreased markedly at the early IRI phase ( 0. 5 h), drastically increased in the 2.0 h group, and then ascended slightly from 6. 0 h to 48.0 h after reperfusion, except for a transient decrease at the time point of 24. 0 h. When b values were 20, 50, 100,200 and 300 s/mm2, the ADC values in the Sham group were (3.47 ±0.53) × 10-3, (3.11 ±0.39) ×10-3, (2.87 ±0.19) ×10-3, (2.56 ±0.37) × 10-3 and (1.95 ±0.33) ×10-3mm2/s, (2.63±0.31)±10-3, (2.47±0.32) ×10-3, (2.12±0.38) ×10-3, (2.01±0.51) ×10-3and (1.61 ±0.17) ×10-3mm2/s in the 0.5 h group, (2.72 ±0.09) ×10-3, (2.51±0. 11) ×10-3, (2.28 ±0.30) ± 10-3, (1.96 ±0. 14) × 10-3 and (1.58 ±0. 17) × 10-3mm2/s in the 24.0 h group, respectively. ADC of 0. 5 h and 24. 0 h groups were significantly lower than that of Sham group (P＜0.05) when b value was under 300 mm2/s.In the Sham, 0.5 h, 2.0 h, 6.0 h, 12.0 h,24.0 h and 48. 0 h IRI groups, they were (80±8), (181 ±34), (413 ±62), (474 ±83), (424 ±41 ),(332 ±41 )and(302 ±39) U/L for the levels of ALT,and (79 ± 10), (454 ±55), (547 ±72), (607±31 ), (649 ±79), (785 ±49) and ( 1526 ± 167) U/L for the AST respectively. The levels of AST and ALT in IRI groups were significantly higher than those in the Sham group ( P ＜ 0. 01 ).Histological findings showed diffuse hepatocytes swelling and erythrocytes depositing in the hepatic sinusoids, portal area, central venous and arterials at the initial phase.With the injury aggravated, inflammatory cell infiltration,hepatocyte nuclear condensation of apoptosis, sinusoidal dissociation and coagulation necrosis developed eventually. Conclusion 3.0 T DWI can monitor the pathological process of rabbit liver ischemia reperfusion injury dynamically, and provides a feasible imaging modality for clinical diagnosis and treatment.

Experimental study of renal damage assessment after injection of iodine contrast medium: the role of blood oxygen level-dependent functional MRI with a 3.0 T system / 中华放射学杂志

Objective To evaluate blood oxygen level-dependent (BOLD) MRI on assessing renal damage after injection of iodine contrast medium with a 3.0 T system. Methods Routine MRI examination,including T1WI and T2WI, and BOLD MRI were performed in 29 SD rats with a 3.0 T system before the injection of iodine contrast agent and 20 min, 24 h, 48 h, 72 h after the injection, respectively. T2 * and R2 * ( = 1/T2 * ) measurements were obtained in the cortex, inner and outer medulla of kidney,respectively. The results obtained before contrast agent administration were considered as the self-controls.AVONA test were used for the comparison of R2 * values in different parts of both kidneys before contrast agent administration. Two-sample t test was used to compare R2 * values before and at each time point after contrast agent administration, and R2 * values in different parts of the kidneys. Results Before contrast agentadministration, R2 * values in outer medulla in both sides of kidney [R2 *left oM = (31.76 ± 2.73 ) / s,R2 * right OM = (32.77±3.07) /s] were higher than those in cortex [R2 * left c=(30.20±3.48) /s,R2 * right c = (28.84 ±3.11 )/s] and in inner medulla [ R2 * letf IM = (29.54 ± 2.42) /s, R2 * right IM =(28.37±2.80) /s ] ( F = 3.357 and 14.961, P＜ 0.05 ). There was no statistical significance in R2 *values in the three parts between left and right kidney, including cortex, outer and inner medulla (P＞0.05). After contrast agent administration, R2* values in outer medulla changed obviously, which reached to the peak values at 20 minutes after contrast agent administration [R2* left OM = ( 43.57 ± 3.84 )/s,R2*right OM= (44.58±3.13) /s] and dropped from 24 hours [R2*left OM = (42.07 ±4.82) /s,R2* right OM = (42.89±3.40) /s]. R2* values in inner medulla and cortex only presented slight changes.Conclusion R2* values reflected the changes of oxygen content in renal cortex and medulla quantitatively,which helped for detecting medullar ischemia and hypoxia. BOLD MR imaging could offer a feasible method for evaluating oxygen metabolism and renal injury in cortex and medulla.

Multi-detector spiral CT manifestations of primary gastric lymphoma / 中国医学影像技术

Objective To observe the multi-detector spiral CT manifestations of primary gastric lymphoma. Methods Multi-detector spiral CT findings of 21 patients with pathologically confirmed primary gastric lymphoma were retrospectively analyzed, the lesions' site, extent, thickness of gastric wall, the enhancement pattern, the situation of gastral cavity and gastric mucosa, and the encroachment of perigastric lymph nodes and other organs were observed. Results Tumors in all 21 patients were non-Hodgkin lymphoma. Multiple lesions were found in 19 patients, while single lesion was detected in 2 patients. CT demonstrated irregular thickening of the gastric wall (8-62 mm) in all 21 patients, including diffuse thickening (n=10), segmental thickening (n=9) and local thickening (n=2). Homogeneous enhancements were found in 19 patients, and lamellar inhomogeneous necrosis were found in 2 patients. Intact mucosal lines were found in 12, and destructed mucosal line in 9 patients, while obscure serous membranes were found in 2, and distinct serous membrane in 19 patients. The stomach showed distensible without significant narrow in 12 patients. The enlargement of perigastric lymph nodes were found in 6 patients. No hepatic encroachment was found. Conclusion Multi-detector spiral CT manifestations of primary gastric lymphoma are relatively specific, and multi-detector spiral CT shows high value for the diagnosis of the disease.

Boundary sign and cortex sign on MR in differentiation between solitary brain metastasis and astrocytoma / 中国医学影像技术

Objective To investigate the value of the boundary sign and cortex sign in differential diagnosis of solitary brain metastasis and astrocytoma. Methods Thirty-one patients with high grade astrocytoma and 42 patients with solitary brain metastasis diagnosed either pathologically or clinically were included in this study. The differential diagnostic value of the boundary and the cortex sign were analyzed retrospectively. Results The boundary sigh was found in 39 of 73 patients, which included 32 patients with solitary metastasis and 7 patients with astrocytoma. The sensitivity and specificity of the boundary sign was 76.20% and 77.42%, respectively, and the positive predictive value for solitary metastasis was 82.05%. The cortex sign was found in 34 of 70 patients, including 25 with astrocytoma and 9 with solitary metastasis. The sensitivity and specificity of the cortex sign was 80.65% and 78.57%, respectively, and the positive predictive value for astrocytoma was 73.53%. The boundary sigh was singlely foundin 24 patients, including 21 with astrocytoma and 3 with solitary metastasis. The area under the curve for both two signs was 0.85. Conclusion The boundary sign and the cortex sign are specific signs in differentiation between solitary brain metastasis and astrocytoma on routine MR series. Combination of this two signs is very useful in distinguishing solitary brain metastasis from astrocytoma.

Multi-slice spiral CT manifestations of portal vein cavernous transformation secondary to tumor emboli from hepatocellular carcinoma / 中国介入影像与治疗学

Objective To observe the multi-slice spiral CT manifestations of cavernous transformation of the portal vein (CTPV) secondary to tumor emboli from hepatocellular carcinoma (HCC). Methods MSCT manifestations of 31 patients of HCC with tumor emboli-induced CTPV proved by operation and pathology were collected and the data were retrospectively analyzed. Results Tumor embolus was detected in both the trunk, left and right branches of PV in 23 patients, accompanied with superior mesenteric vein and/or splenic vein and inferior vena cava's tumor embolus in 4 and infiltration of gallbladder in 1 of 23 patients, as well as in the trunk and left branch in 1, and in the trunk and right branch of PV in 5 patients, accompanied with right hepatic vein and/or inferior vena cava's tumor embolus in 2 and in the portal trunk and superior mesenteric vein in 1, only in the right branch in 1 patient, respectively. Tumor emboli were isodense in plain CT scan, but enhanced with obvious degrees in arterial phase and filling defects in portal venous phase. There were collateral vessels around portal vein. Lateral branches around hilar bile duct, the open of venous plexus around fossa of gallbladder, lateral veins around gastric fundus and lesser curvature, lateral veins of lower part of esophagus and expansion of splenic vein were found in 31 (100%), 19 (61.29%), 21 (67.74%), 7 (22.58%) and 15 patients (48.38%), respectively. Conclusion Tumor emboli-induced CTPV from HCC has specific MSCT findings being helpful to the diagnosis.

Comparison of Resovist and Gd-DTPA as susceptibility contrast agents for MR perfusion weighted imaging of hyperacute cerebral infarction in rats / 中国医学影像技术

Objective To compare the value on assessment of perfusion weighted imaging (PWI) using Gd-DTPA and the superparamagnetic iron oxide (SPIO) particles (Resovist) in the experimental model of hyperacute cerebral infarction in rats. Methods Thirty Wistar rats were randomly divided into Group A and B (each n=15). After occluding the left middle cerebral artery with thread for 1 h in all rats, two dynamic MR perfusion imaging series were acquired after intravenous bolus injections of 8 μmol Fe/kg SPIO (Group A) and 0.2 mmol/kg Gd-DTPA (Group B), respectively. The doses were chosen to obtain similar maximum signal change in normally perfused brain. The perfusion imaging was compared between the region of interest (ROI) in the core area with severe ischemia and in the penumbra area of moderate ischemia. The parameters were compared between two groups with pathologic findings and TTC stain. Results The first-passage profiles were found to be similar for Gd-DTPA and SPIO, both in the core area with severe ischemia and in the penumbra area of moderate ischemia of rats models. No statistical difference of the parameters (CBV, MTT, TTP) of PWI for ischemic penumbra was detected between Group A and B. Conclusion The efficacy of the Resovist using in the MR PWI is similar to Gd-DTPA for diagnosis of the perfusion reduction in the rat stroke models. Strong susceptibility effects may be achieved with small injection volumes. Resovist may play an important role in MR PWI.

Optimization of scan parameters for proton MR spectroscopy on liver in vivo at 3.0 T / 中华放射学杂志

Objective To characterize the effect of the ~1H-MRS scan parametem, including the type of coil, TE,NSA and VOI, on shimming, water suppression, spectral signal to noise ratio(SNR)and the stability of the baseline of liver in vivo. Methods ~1H-MRS of liver in vivo was performed prospectively on GE Signa Excite HD 3.0 T system in 46 volunteers. Point-resolred spectroscopy(PRESS)sequence with built-in body coil and eight-channel torso phased-array coils was applied. After the localized scan,the first PRESS sequence with a TR of 1500 ms,TE of 30 ms. VOI of 2 cm×2 cm×2 cm and NSA of 64 times was acquired using eight-channel torso phased-array coils.(The first PRESS sequence parametem was deemed as A).Then,the sequence was repeated with alteration of the three parameters including the type of coil,TE and size of VOI.(Changed parameters deem as B).The data were analyzed with the Wilcoxon matched pairs signed test.0 mark:A is similar to B,1 mark:A better than B,-1 mark:A worse than B.Results SNR(-1 mark 0 pair,0 mark 1 pair,1 mark 10 pair,Z=-3.162,P=0.002)was better in data(n=11)with eight-channel torso phased-array coils(A)than that with the built-in body coil(B),but the autoshimming line width with eight-channel torso phased-array coils were inferior to those with built-in body coil (-1 mark 8 pair,0 mark 2 pair,1 mark 1 pair,Z=-2.511,P=0.012).SNR was better in data(n=13)with TE of 30 ms(A)than that at the sequence with TE of 90 ms(B)(-1 mark 2 pair,0 mark 0 pair,1 mark 11 pair,Z=-2.496,P=0.013).whereas baseline stability was,poorer in the former(-1 mark 10 pair,0 mark 2 pair,1 mark 1 pair,Z=-2.333,P=0.020).SNR at the sequence(n=10)with VOI of 2 cm×2 cm×3 cm(B)was better(-1 mark 6 pair,0 mark 4 pair,1 mark 0 pair,Z=-2.449,P=0.014)than that at the sequence(n=29)with VOI of 2 cm ×2 cm × 2 cm(A),but poorer(-1 mark 0 pair,0 mark 5 pair,1 mark 5 pair,Z=-2.041,P=0.041)auto-shimming line width was shown. By comparison the sequences with NSA of 128 times(B)and NSA of 64 times(A),the former could provide better spectrum SNR(-1 mark 21 pair,0 mark 7 pair,1 mark 1 pair,Z=-4.264,P=0.000).Conclusion It is more easy to achieve a homogeneous bo magnetic field using a small size of VOI and builtin body coli.The sequence with VOI of 2 cm ×2 cm ×3 cm.NSA of 128 times is recommended for clinical use. Increase VOI and NSA are helpful to improve SNR. Longer TE is helpful to improve baseline stability.

Reproducibility of normal hepatic proton MRS at 3.0T / 中国医学影像技术

Objective To explore the reproducibility of normal hepatic MRS at 3.0T. Methods The hepatic proton MRS was performed with GE Signa Excite HD 3.0T system and eight-channel torso phased-array coils using PRESS sequence. Thirty-one healthy individuals were enrolled in this study. Liver spectra were collected with TR of 1500 ms, TE of 30 ms, ROI of 2 cm×2 cm×2 cm, NSA of 64 times. The outcomes were statistically analyzed with Wilcoxon signed ranks test and Spearman correlation test.Results There was no significant difference of signal to noise ratio (Z=-0.535,P=0.593), baseline stability (Z=-0.333, P=0.739), linewidth of automatic shimming (Z=-0.305, P=0.761), water suppression (Z=-1.232, P=0.218), height of lipid peak (Z=-0.558,P=0.557), area under the lipid peak (Z=-1.195,P=0.232), height of water peak (Z=-0.647,P=0.518) and area under the warter peak (Z=-0.118, P=0.906) between first examination and second examination. Correlation coefficient of the former and the later measurements of lipid area and water area were 0.784 (P<0.001) and 0.799 (P<0.001), respectively.Conclusion The reproducibility is good for in vivo liver proton MRS at 3.0T.