Application of kernel density estimation in predicting bone marrow dose of radiation therapy for gynecological tumors / 中华放射肿瘤学杂志

Objective:To predict the dose of lumbosacral spine (LS) and pelvic bone marrow (PBM) based on kernel density estimation (KDE) in patients with gynecological tumors.Methods:Fifteen patients with gynecological tumors receiving radiotherapy plans with dose limitation for LS and PBM in our hospital were selected as training data for machine learning. Another 10 cases were selected as the data for model validation. The minimum directional distance between the dose point in the organs and the edge of the planned target volume for the LS and PBM was calculated. Model training was performed by KDE. The accuracy of the model prediction was evaluated by the root mean square error. The model was utilized to predict the actual planned doses of the LS and PBM, and a linear fitting was performed on the predicted dose volume histogram (DVH) and actual results. The prediction effect was assessed by the goodness of fit R 2. Results:In terms of the DVH parameters required by the planner, the prediction doses from the model were similar to those of the verification plans: the difference of PBM V 40Gy was 2.0%, the difference of the mean dose was 1.6 Gy, and the difference of LS V 10Gy was -0.4%. In the unrequired DVH parameters, except for the PBM V 10Gy, the predicted values of the model were significantly high. The difference between the DVH predicted by the model and the actual plan was small, and the R 2 of the LS and PBM were 0.988 and 0.995, respectively. Conclusions:The model based on KDE method can accurately predict the doses of the LS and PBM. This model can also be used as a method to ensure the quality of the plan, and improve the consistency and quality of the plan.

Progress of signaling pathways regulating the sensitivity of irradiation in cancer therapy / 肿瘤研究与临床

Radiotherapy characterized by invasive, localization and low toxicity has been recognized as one of the standard cancer therapy regimes, especially for non-surgically resectable advanced cancers. However, inherent and acquired resistance of cancer cells has significantly impeded the efficacy of radiotherapy. Of all the resistance determinants, varieties of anti-apoptotic signaling pathways or anti-survival proteins aberrant activation in malignant tumor cells play crucial roles in radiation insensitivity. This paper mainly focuses on clarifying the roles of the interesting key molecular signals including Ras, insulin-like growth factor type 1 receptor, transforming growth factor-beta, histone deacetylase and heat shock protein 90 in regulating radiotherapy sensitivity, in order to find the potential targets to improve the efficacy of radiotherapy.

Hemobilia following laparoscopic cholecystectomy: computed tomography findings and clinical outcome of transcatheter arterial embolization.

BACKGROUND: Hemobilia following laparoscopic cholecystectomy (LC) can occur in the early or late postoperative course and poses a diagnostic and therapeutic challenge. PURPOSE: To assess computed tomography (CT) findings and clinical outcomes after transcatheter arterial embolization (TAE) in patients presenting with hemobilia following LC. MATERIAL AND METHODS: Fourteen patients treated for hemobilia following LC were included in the study. Three patients were diagnosed by endoscopy and 11 by abdominal contrast-enhanced CT. Coils or microcoils were superselectively deployed to occlude the bleeding vessel during TAE. Abdominal CT findings of hemobilia, and the success rate and complication of TAE were observed. RESULTS: Abdominal CT provided the following signs of hemobilia: hematoma within the abdominal cavity and gallbladder fossa, blood clots containing high attenuation within the bile duct, biliary dilatation, pseudoaneurysm of the right hepatic artery, contrast extravasation, enhancement of the bile duct wall, and hypoperfusion of the right lobe. The success rate of TAE was 100% and rebleeding did not occur in any patient. Post-embolization syndrome and hepatic ischemia occurred in nine patients, which was associated with age and the time interval between the LC and TAE. CONCLUSION: Abdominal CT provided direct signs that can aid in the diagnosis of hemobilia after LC. TAE allowed for successful treatment of hemobilia with minor complications.

Imaging performance of hepatic inflammatory myofibroblastic tumor / 中国医学影像技术

Objective To assess the radiological imaging findings of hepatic inflammatory myofibroblastic tumor and to discuss the appropriate morphological classification.Methods A total of 22 patients with hepatic inflammatory myofibroblastic tumor confirmed by pathology were enrolled.Imaging performance of hepatic inflammatory myofibroblastic tumor were analyzed and the lesions were classified into appropriate type based on the imaging findings.Results Totally 23 lesions were found in 22 patients.The typical imaging features included great enhancement at later phase (13/20),moth eat en central necrosis (12/23) and peripheral shell (12/23).Seed in fruit was the most typical classification (8/23),followed by Seedless fruit (7/23).Conclusion Hepatic inflammatory myofibroblastic tumur typically shows as a single nodular lesion with moth eaten necrosis and peripheral shell like a Seed in fruit.The enhancement at later phase (especially the peripheral enhancement) can be regarded as a particular feature.

Role of cell apoptosis regulated by P53 in treatment of hepatocellular carcinoma / 临床肝胆病杂志

P53 abnormality or mutation is commonly seen in patients with hepatocellular carcinoma (HCC), and therefore, restoration of P53 function has become a research hotspot in the treatment of HCC.This article reviews the association of P53 with Bcl-2 protein family, microRNA, TGFβ, HBV, HCV, and AKT and the role of P53 in regulating cell apoptosis, in order to provide clues for improving the therapeutic outcome of HCC.

CT and MRI Findings and Follow-up Changes of Infantile Hepatic Hemangioendothelioma / 中国医学影像学杂志

Purpose To analyze the CT and MRI findings as well as follow-up changes of infantile hepatic hemangio-endothelioma (IHE),so as to provide basis for guiding the clinical establishment of therapeutic protocols.Materials and Methods The clinical data of 21 infants with IHE were analyzed retrospectively,including the imageological manifestations in initial diagnosis and during follow-up.Among the infants,3 received non-enhanced and enhanced scan of both CT and MRI,13 received non-enhanced and enhanced scan of CT only,while 5 received non-enhanced and enhanced scan of MRI only.All infants received ultrasonic examination.Results In non-enhanced CT scan,the tumor was marked by multiple or single intrahepatic low-density nidus with clear boundary,while non-enhanced MRI showed low T1WI signal and high T2WI signal.Enhanced scan of single IHE in arterial phase indicated notable nodular,streak-like and annular enhancement of the edge,while that in delayed period suggested a characteristic of progressive enhancement of tumor from periphery to center.There was not enhancement in necrotic zone in the center of large nidi all the time,while streak-like calcification nidi were found in partial nidi.Obvious whole-tumor enhancement was found in most nodes in the multiple nodular IHE,while moderate enhancement in partial nodes.The enhancement in each enhanced period decreased gradually,and most nidi in delayed period showed slightly high-density or isopycnic shadow.3 infants were misdiagnosed with hepatoblastoma and received surgical resection,but none had recurrence during postoperative ultrasonic follow-up.The rest infants were treated with oral administration of Propranolol and then followed up,and the follow-up results showed that most nidi shrunk to different extent while partial nidi disappeared completely.Conclusion IHE is marked by multiple nidi or single nidus,and the characteristic manifestations of CT and MRI are beneficial to promoting the accuracy rate of diagnosis of IHE.Tumor may shrink spontaneously or disappear if Propranolol is orally administered in treatment of IHE.

Iatrogenic hemobilia: imaging features and management with transcatheter arterial embolization in 30 patients.

PURPOSE: We aimed to evaluate the imaging features of computed tomography (CT) and angiography and the efficacy of transcatheter arterial embolization (TAE) in patients with hemobilia of different iatrogenic causes. METHODS: Thirty patients with hemobilia were divided into two groups according to their iatrogenic causes, i.e., group 1, 11 patients (36.7%) with transhepatic intervention and group 2, 19 patients (63.3%) with surgical procedures in the hilar area. Seventeen patients (56.7%) underwent abdominal contrast-enhanced CT before selective angiography. Polyvinyl alcohol particles, gelatin sponges, and coils were used for TAE. Data from the two groups were compared using Fisher's exact test and the Mann-Whitney U test. RESULTS: Contrast-enhanced CT showed a hematoma, extravasation of contrast material, and pseudoaneurysm. The bleeding source was determined by angiographic features in all patients, which were not significantly different between the two groups (P = 0.127), and pseudoaneurysm was the most common. The embolic material and number of coils used for TAE were significantly different between the two groups (P < 0.001), but the embolization was technically successful in all patients. The clinical success rate of the first embolization was 100% in group 1 vs. 84.2% in group 2. The overall clinical success rate of TAE was 100% in all patients. The complication rate was 63.6% in group 1 vs. 68.4% in group 2 (P = 1.000). CONCLUSION: CT was useful in diagnosing hemobilia, and angiograms enabled determination of the bleeding source. Pseudoaneurysm was one of the most common angiographic features. TAE was successfully performed with different embolic materials on the basis of the iatrogenic cause and bleeding location.

Study advances on the roles of apoptosis in hepatocellular carcinoma therapy / 实用肿瘤学杂志

Hepatocellular carcinoma ( HCC ) is one of the commonest malignant tumors in China .The therapeutic effects of conventional therapies including surgery resection at early stage ,chemotherapy or radiothera-py are greatly less than expected .One of the most possible reasons is the blockage of apoptosis in HCC cells .This review collects literatures about the studies on the roles of key signal pathways including RA ,STAT3,PDT,p53,β-catenin,TRAIL,microRNA and RAS in HCC therapy .This study may contribute greatly to providing outline in-sights for using apoptosis induction in liver cancer therapy .We hope it can promote the development liver cancer therapy in China .

The role of apoptosis in pancreatic cancer therapy / 实用肿瘤学杂志

Pancreatic adenocarcinoma ( PAC) is still a refractory human digest malignancies due to multi-faceted causes ,late diagnosis and insensitive to traditional chemo -and radio-therapy .Resistance to apoptosis could be one of the most relevant mechanisms for PAC to escape any non -surgical therapy .This review aims to clear up the main deregulated apoptosis signal pathways over the years and to find out the abnormal molecule tar -get(s),and therefore,provide novel concepts for PAC molecular targeting therapy .

Current status and confusion in comprehensive interventional therapy for hepatocellular carcinoma / 临床肝胆病杂志

In recent years,hepatocellular carcinoma (HCC)has become the second leading cause of cancer-related death worldwide.Due to the insidious onset of this disease,only 20%-30%of the patients with HCC have the opportunity for surgical resection or liver transplan-tation.At present,interventional therapy has become the first choice for patients with intermediate-stage HCC and some patients with late-stage HCC,and more and more scholars have realized the importance and necessity of comprehensive interventional therapy for HCC.The comprehensive interventional therapy of transcatheter arterial chemoembolization (TACE)in combination with various methods (TACE com-bined with local treatment,TACE sequential surgery,or TACE combined with systemic treatment)provides many therapeutic approaches and achieves good therapeutic effects.However,the indications,timing,and recurrence and metastasis after treatment for such combination ther-apies await further investigation.

Research advances in sorafenib-induced apoptotic signaling pathways in liver cancer cells / 临床肝胆病杂志

Currently, sorafenib is the multi-target inhibitor for the treatment of advanced primary liver cancer, and can effectively prolong the progression-free survival and overall survival in patients with advanced primary liver cancer. The application of sorafenib in the targeted therapy for liver cancer has become a hot topic. Major targets or signaling pathways include Raf/Mek/Erk, Jak/Stat, PI3K/Akt/mTOR, VEGFR and PDGFR, STAT, microRNA, Wnt/β-catenin, autolysosome, and tumor-related proteins, and sorafenib can regulate the proliferation, differentiation, metastasis, and apoptosis of liver cancer cells through these targets. This article reviews the current research on the action of sorafenib on these targets or signaling pathways to provide useful references for further clinical research on sorafenib.

The role of MAPK signaling pathway in development/progression and treatment of liver cancer / 临床肝胆病杂志

Abnormal activation of the mitogen-activated protein kinase (MAPK) signaling pathway is closely associated with the development, progression, and metastasis of liver cancer. This article introduces the expression of MAPK proteins in liver cancer and its role in the proliferation, differentiation, and metastasis of liver cancer, and elaborates on the value of the MAPK signaling pathway in the treatment and prognostic evaluation of liver cancer. It is pointed out that the MAPK signaling pathway plays an important role in the development/progression and treatment of liver cancer and is a potential molecular target for the treatment and prognostic evaluation of liver cancer.

Iterative model reconstruction and hybrid iterative reconstruction techniques iDose4 in low-dose abdominal CT: comparison of image quality in evaluation of hypovascular metastases of liver / 中华放射学杂志

Objective To assess the image quality of iterative model reconstruction algorithm (IMR) compared with hybrid iterative reconstruction algorithm (iDose4) for hypovascular hepatic metastases.Methods Medical history and pathological results of 33 cases with primary malignant tumor were retrospective analyzed.Follow-up with enhanced CT or enhanced MRI at more than 3 months confirmed hypovascular metastases in these patients.All patients underwent abdominal CT scanning and dynamic enhanced CT scanning.Portal vein phase of low dose scanning data were taken as the research object.According to the different tube currents and reconstruction algorithm,the images were divided into 4 groups.Group A included images with tube current of 175 mAs and IMR post-processing (17 cases).Group B included images with tube current of 175 mAs and iDose4 post-processing (17 cases).Group C included images with tube current of 125 mAs and IMR post-processing (16 cases).Group D included images with tube current of 125 mAs and iDose4 post-processing (16 cases).In the cases with multiple lesions,the largest lesion was selected to evaluate.For each image of the objective evaluation [including noise,the signal-to-noise ratio (SNR),contrast to noise ratio (CNR)] and subjective evaluation (including lesion sharpness,necrosis interface and diagnostic confidence).The CT dose index of each scanning was recorded.The objective evaluation,subjective evaluation indexes were compared by paired samples t test and Wilcoxon signed rank test.Results The tube current of Group A and Group B were (7.7± 1.8) and (12.8±3.7)HU,while CNR were 10.3 ±2.6 and 5.6± 1.4,SNR were 13.2±3.2 and 8.1 ± 2.2,and the differences were statistically significant (t values were 9.966,12.670,9.203;P＜0.01).The tube current of Group C and Group D were (7.2±1.3) and (9.9±1.8)HU,while CNR were 7.4±2.0 and 3.7±0.9,SNR were 13.9±2.9 and 9.8±1.9,and the differences were statistically significant (t values were 9.209,12.320,9.628;P＜0.01).The lesion sharpness score of Group A and Group B were 4.95±0.24 and 4.29±0.59,while the necrosis interface score were 4.76 ± 0.36 and 3.68 ± 0.30,diagnostic confidence score were 4.94± 0.24 and 4.44 ±0.56,and the differences were statistically significant (P＜0.05).The lesion sharpness score of Group C and Group D were 3.94±0.68 and 3.56±0.63,while the necrosis interface score were 3.91±0.64 and 3.03±0.50,diagnostic confidence score were 4.19±0.40 and 3.94±0.44,and the differences were statistically significant (P＜0.05).CTDIvol of 175 mAs group and 125 m As group were (11.83±0.28) and (8.44±0.24) mGy respectively.Conclusion Compared with iDose4,iterative reconstruction technology IMR significantly reduces the image noise and enhances image quality of hypovascular hepatic metastases.

Changes in energy metabolism in the quadriceps femoris after a single bout of acute exhaustive swimming in rats: a ³¹P-magnetic resonance spectroscopy study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Little is known about the value of (31)P-magnetic resonance spectroscopy ((31)P-MRS) in in vivo assessment of exhaustive exercise-induced injury in skeletal muscle. We aimed to evaluate the value of a (31)P-MRS study using the quadriceps femoris after a single bout of acute exhaustive swimming in rats, and the correlation between (31)P-MRS and histological changes.</p><p><b>METHODS</b>Sixty male Sprague-Dawley rats were randomly assigned to control, half-exhaustive, and exhaustive exercise groups. (31)P-MRS of the quadriceps femoris of the right lower limb was performed immediately after swimming exercise to detect Pi, PCr, and β-ATP. The Pi/PCr, Pi/β-ATP, PCr/β-ATP, and PCr/(PCr+Pi) were calculated and pH measured. Areas under the receiver operating characteristic curve (AUCs) were calculated to evaluate the diagnostic potential of (31)P-MRS in identifying and distinguishing the three groups. HE staining, electron microscopy and desmin immunostaining after imaging of the muscle were used as a reference standard. The correlation between (31)P-MRS and the mean absorbance (A value) of desmin staining were analyzed with the Pearson correlation test.</p><p><b>RESULTS</b>Pi, PCr, Pi/PCr, and PCr/(PCr+Pi) showed statistically significant intergroup differences (P < 0.05). AUCs of Pi, PCr, Pi/PCr, and PCr/(PCr+Pi) were 0.905, 0.848, 0.930, and 0.930 for the control and half-exhaustive groups, while sensitivity and specificity were 90%/85%, 95%/55%, 95%/80%, and 90%/85%, respectively. The AUCs of Pi, PCr, Pi/PCr and PCr/(PCr+Pi) were 0.995, 0.980, 1.000, and 1.000 for the control and exhaustive groups, while sensitivity and specificity were 95%/90%, 100%/90%, 100%/95%, and 100%/95%, respectively. The AUCs of Pi, PCr, Pi/PCr, and PCr/(PCr+Pi) were 0.735, 0.865, 0.903, and 0.903 for the half-exhaustive and exhaustive groups, while sensitivity and specificity were 80%/60%, 90%/75%, 95%/65%, and 95%/70%, respectively. In the half-exhaustive group, some muscle fibers exhibited edema in HE staining, and the unclear Z-discs and the mitochondria with vacuolar degeneration under electron microscopy. Compared with the half-exhaustive group, muscle fiber edema was increased in the exhaustive group, and the Z-discs were broken and the mitochondria exhibited marked vacuolar degeneration under electron microscopy. There were significant difference in A values of desmin staining in the right vastus lateralis among the control, half-exhaustive, and exhaustive groups with 0.58 ± 0.06, 0.30 ± 0.04, and 0.21 ± 0.02, respectively (P < 0.05). Histological examination also showed injury-induced changes in the vastus lateralis among the different intensities groups. Statistically a moderate correlation between (31)P-MRS and desmin was observed, the correlation coefficients of Pi, PCr, Pi/PCr, and PCr/(PCr+Pi) were -0.706, 0.709, -0.726, and 0.791, respectively (P < 0.01).</p><p><b>CONCLUSIONS</b>(31)P-MRS can effectively reflect the changes in energy metabolism in the skeletal muscle after a single bout of acute exhaustive swimming in rats. Based on the significant correlation between (31)P-MRS parameters and histological changes, the changes of Pi, PCr, Pi/PCr, and PCr/(PCr+Pi) can indirectly reflect the degree of exercise-induced injury.</p>

Assessment of muscle perfusion in ischemic rabbit hindlimb treated by intravenous implantation of bone marrow mesenchymal stem cells with perfusion CT / 中华放射学杂志

Objective To evaluate the application of CT perfusion in the assessment of muscle perfusion in ischemic rabbit hindlimb treated by implantation of bone marrow mesenchymal stem cells.Methods Twenty rabbits were divided into two groups randomly (each n =10).Bone marrow mesenchymal stem cells were injected into the left ischemic hind limbs of animal models of intravenous injection group,with same volume of normal saline injected into the control group.Twenty-eight days later,the collateral circulation and blood vessel neogenesis were examined by Toshiba Aquilion One 320-MSCT and pathological approaches.t test and Pearson test were used to compare the parameters.Results The results show that rAF,rBV,rClearance,rMVD were 1.15 ±0.67,1.19 ±0.32,0.62 ±0.20,and 1.34 ±0.28 in intravenous injection group and 0.57 ±0.17,0.74 ±0.19,2.06 ±0.15,0.62 ±0.19 in the control group respectively.There was significant difference of rAF,rBV,rClearance and rMVD between the intravenous injection group and the control group(t =5.75,5.01,-2.81,6.43 respectively,P ＜ 0.01).There was significant correlation between rBV,rAF,rC and rMVD (r =0.857,0.811,0.615,P ＜ 0.01).Conclusion CT perfusion imaging is a relatively accurate technique to assess changes of muscle perfusion in ischemic rabbit hindlimb treated by implantation of bone marrow mesenchymal stem cells.

Evaluate the Influence of Monochrome Display on the Detection of Pulmonary Nodules Based on ROC Theory / 中国医科大学学报

Objective Evaluate the influence of medical monochrome liquid crystal display (LCD) with different resolutions on the detection of pulmonary nodules.Methods Ninety-three direct digital radiography (DR) chest images were selected on-line from picture archiving and communication system (PACS),including 38 positive,32 suspected and 23 normal cases.All of the images were confirmed by CT.These positive images were divided into group A and B according to the diameter of nodules.Three experienced radiologists blindly read the 93 images using three types of displays with different resolutions.Regarding the presence of nodule,five-point confidence system was used:definitely absent,probably absent,indefinite,probably present and definitely present.All observers marked their confidence levels of each image according to the presence of pulmonary nodule on different displays.Software SPSS 13.0 was employed for statistical analysis.Results In the group-A cases,the areas under ROC curves were 0.643,0.686 and 0.739,and in the group-B cases,those were 0.813,0.832 and 0.846 respectively.There was no difference in the detection efficacy among different radiodiagnostic systems.Conclusion Regardless of post-processing tools,it was equivalent to detect pulmonary nodules with different diameters of Group A or B among medical monochrome LCDs with different resolutions.

Influence of monochrome LCDs with different resolutions for the detection performance of pulmonary micro-nodule / 中国医学影像技术

Objective To assess the influence of medical monochrome liquid crystal displays (LCD) with different resolutions for the detection performance of micro-nodules (diameter <10 mm) on chest radiograms. Methods Eighty-seven DR chest images that were verified with CT were selected from PACS on-line, including 32 positive images, 32 suspected images and 23 normal images. The diameters of all nodules were lower than 10 mm. Three of high-, mid- and low-experienced radiologists who participated in the ROC study interpreted these 87 images using three types of LCDs with different resolutions, respectively. Regarding the presence of nodule, five-point confidence level rating scale was used, i.e. definitely absent, probably absent, possibly present, probably present and definitely present. All observers marked their confidence levels of every image according to the presence of pulmonary nodule on different displays. Software SPSS 13.0 was used for statistical analysis. Results AUC increased with the increasing resolutions and radiologists' experiences in 2MP, 3MP, 5MP displays. For the detection performance of pulmonary nodules (diameter <10 mm), there was no significant difference among different types of displays or different aptitudes of radiologists. Conclusion It's equivalent for the detection performance of pulmonary nodule (diameter <10 mm) on 2MP, 3MP and 5MP medical monochrome LCD when no restriction on the use of image post-processing tools. Highly-experienced radiologist can get the most information when using 5MP display. It is advisable to combine the diagnostic workstation system with high-, mid- and low-resolution monitors, and reasonable equipment scheme between different types of displays and different aptitudes of radiologists could result in better cost-efficacy.

Comparison of body artery imaging between dual-energy CT angiography and traditional 3D CT angiography / 中国医学影像技术

Objective To evaluate the effect of automatic bone and plaque removal on image quality and grading of steno-occlusive lesions in patients undergoing dual energy CT angiography (DE-CTA) of body artery. Methods DE-CTA was performed in 23 patients with suspected body vascular disease. Separate datasets were calculated for each of the two tubes and used to generate automatically bone-subtracted images (ABS) as well as additional manual bone removes after plaque subtracted images (ABPS). In addition, a weighted average dataset from both dual energy acquisitions resembling routine 3D CT acquisition was used for automatic bone remove (ABR). Residual bone in the ABR dataset was removed manually (ABR-M). Operator time for bone removal was measured, while effectiveness of bone subtraction and the time needed of ABPS and ABR-M was assessed. Compared with MPR, ABR images and stenosis grading in plaque subtracted were assessed with two radiologists. Results The imaging quality of ABR was superior to that of ABS (P<0.05). The time needed of ABPS was (7.8±4.3) min, significantly lower than that of ABR-M (11.4 min±2.5 min, P<0.05). A total of 325 steno-occlusive lesions were assessed. The sensitivity, specificity of DE-CTA and traditional 3D CTA was 95.74%, 96.19% and 92.93%, 97.87%, respectively. Conclusion The imaging quality is good after automatic bone and plaque subtraction of DE-CTA. Automatic plaque subtraction for the first time provides a true CTA imaging which is easy to interpret and reduces the need for further post-processing. The diagnosis of vascular stenosis with DE-CTA is also accurate, and the time spent in post-processing is less than that of traditional 3D angiography.

Cortical activations for covert and overt picture naming on fMRI / 中国医学影像技术

Objective To investigate cortical activation patterns for covert and overt picture naming with functional magnetic resonance imaging (fMRI). Methods fMRI data were collected on 24-27 years old volunteers during performance of covert and overt picture naming. After statistical postprocessing analysis, head movement data were compared across tasks and average neural activation maps were available for both tasks. Results Mean and maximal translations of head movement in covert picture naming were less than those in overt picture naming, but the difference has no statistical significance (P=0.23). It was shown that covert picture naming involved an orchestration of bilateral occipital gyri and cerebellums, bilateral supplementary motor area, postcentral gyri, inferior frontal gyrus and anterior cingulate cortex. Activations in overt picture naming included those in covert naming (but more intensive), bilateral precentral gyri and posterior superior temporal gyri, left anterior superior temporal gyrus, bilateral thalamus, basal ganglia, and left insula. Conclusion Covert and overt picture naming are two different tasks involving different neural processing networks and levels. They can not be taken as substitutes for each other.

3.0T MRI features of normal acetabular labrum in children / 中国医学影像技术

Objective To observe the 3.0T MRI features of normal acetabular labrum and variation in children. Methods MR appearances of normal acetabular labra in 53 children aged from 4 days to 14 years were reviewed retrospectively. The children were divided into four groups according to the age:group A:0-3 years; group B:4-7 years; group C:8-11 years; group D:12-14 years. All of them were examined with 3.0T MR including axial and coronal sequences. Results ①MR appearances of normal acetabular labra could be classified into 3 types:triangle, flat-shape and absent in shape. Triangle was the most common (78.29%). ②There was remarkable difference in the distribution of labra morphology among different groups and different portions of hip. Triangle was most commonly observed in group D and on the anterior portion. ③High signal intensity of normal acetabular labra in MRI was most frequently seen on the anterior site of hip. Conclusion The shape and signal intensity of normal acetabular labrum in children varies in different age groups and different portions.