ObjectiveTo investigate the value of diffusion weighted imaging (DWI) combined with three-dimensional volumetric interpolated breath-hold examination (3D-VIBE) in evaluating metastatic lymph nodes secondary to hilar cholangiocarcinoma. MethodsFrom July 2009 to March 2011, DWI examination was performed in 37 patients with hilar cholangiocarcinoma, which was compared with 3D-VIBE sequences. The morphological characteristics and distribution were analyzed for metastatic and nonmetastatic lymph nodes. Signal intensity (SI) was measured on DWI images and apparent diffusion coefficient (ADC) was calculated for each lymph node. The SI of lymph nodes (SILN） and liver (SIliver) were also measured and the ratio of SI was calculated. The ADC and the ratio of SI were compared between metastatic and nonmetastatic lymph nodes. ResultsThere were fifty-nine groups of lymph nodes in 37 patients with hilar cholangiocarcinoma, fifty-one groups were revealed in both DWI and 3D-VIBE sequences, and eight groups were only demonstrated in one sequence (P=0.070). The short diameters were (1.05±0.42) cm and (0.78±0.22) cm on 3D-VIBE images for metastatic and nonmetastatic lymph nodes, respectively (P=0.030). The ADC value in metastatic lymph nodes was (1.64±0.3)×10-3 mm2/s, which was significantly lower than that in nonmetastatic lymph nodes 〔(2.28±0.79)×10-3 mm2/s〕 on DWI images (P=0.033). There were no significant differences in SILN/SIliver between metastatic and nonmetastatic lymph nodes on images of portal venous phase and 3 min delayed contrast-enhanced phase. ConclusionsDifferences of ADC and short diameter can provide valuable information to differentiate metastatic lymph nodes with nonmetastatic lymph nodes. When combined with 3D-VIBE sequence, DWI is more effective in evaluating metastatic lymph nodes secondary to hilar cholangiocarcinoma.
ObjectiveTo explore the significance of ultrasound combined with magnetic resonance imaging (MRI) in the diagnosis of pernicious placenta previa (PPP).MethodsA total of 101 patients with suspected PPP admitted to Chengdu Women’s and Children’s Central Hospital from January 2016 to February 2019 were retrospectively analyzed. The surgical results were used as the gold standard, and the diagnostic value of ultrasound, MRI, ultrasound combined with MRI was compared.ResultsSurgery results showed that among the 101 patients with suspected PPP, 79 patients had positive PPP diagnosis and 22 patients had negative PPP diagnosis. There was no significant difference in the diagnostic sensitivity, negative predictive value, or diagnostic coincidence rate of PPP among ultrasound, MRI, and ultrasound combined with MRI (P>0.05). The diagnostic specificity of the series combination of ultrasound and MRI (86.36%) was higher than that of ultrasound (59.10%), MRI (59.10%), and the parallel combination of ultrasound and MRI (31.32%), and the differences were statistically significant (P<0.05). The diagnostic coincidence rates of abnormal placental attachment of MRI (96.20%) and the parallel combination of ultrasound and MRI (96.20%) were higher than that of ultrasound (87.34%) and the series combination of ultrasound and MRI (87.34%) (P<0.05).ConclusionsUltrasound combined with MRI has a high diagnostic value for PPP. If necessary, ultrasound combined with MRI can be considered to improve the diagnostic efficiency.
Object To evaluate the sensitivity, specificity, and accuracy of magnetic resonance imaging (MRI) for the preoperative T staging of gastric cancer. MethodsThe databases such as the PubMed, Cochrane Database Systematic Reviews, EMbase, CNKI, and Wanfang Data were searched on computer from 1993 to 2012.The reviewers screened the trials according to inclusion and exclusion criteria strictly, extracted the data, and assessed the methodology quality.Meta-analysis were performed using the Metadisc 1.40 software, the pathology diagnosis as gold standard.The acquired pooled sensitivity, specificity, and summary receiver operating characteristic curve (SROC) were used to describe the value of MRI in T staging. ResultsEight case-control studies involving 302 patients with gastric cancer were included in the study.The pooled statistical results of Meta-analysis showed that:the pooled sensitivity and specificity of MRI for T1-stage gastric cancer were 85%(55%-98%) and 97%(91%-99%) respectively, and the area under the SROC curve (AUC) was 0.961.The pooled sensitivity and specificity of MRI for T2-stage gastric cancer were 73%(60%-84%) and 93%(89%-96%) respectively, and the AUC was 0.935.The pooled sensitivity and specificity of MRI for T3-stage gastric cancer were 87%(81%-92%) and 82%(74%-88%) respectively, and the AUC was 0.914.The pooled sensitivity and specificity of MRI for T4-stage gastric cancer were 75%(62%-86%) and 97%(94%-99%) respectively, and the AUC was 0.963. ConclusionMRI has the high consistency in preoperative T staging with pathology, and should be recommended as a preferred to increase the accuracy of preoperative staging, and improve the prognosis.
Objective To assess value and limitations of non-invasive methods in assessing liver fibrosis．Methods By summarized current situation and advancement of serum fibrotic markers, ultrasound, CT and MRI in assessing liver fibrosis, we investigated their value and limitations. Results In addition to diagnosis, non-invasive methods of assessing liver fibrosis assess severity of liver fibrosis. For liver fibrosis, however, non-invasive methods can not monitor effectively reaction to therapy and progression. Conclusion Non-invasive methods play important roles in diagnosis and assessing severity of liver fibrosis, and reduce the need of liver biopsy.
Objective To observe the results of function MRI and perimetry in patients with visual pathway diseases.Methods Three patients (6 eyes) with pituitary adenoma and craniopharyngioma diagnosed via pathological examination and three healthy volunteers aged from 24 to 30 were collected. The best corrected visual acuity was nonlight perception1.0 in the 6 sick eyes and 1.0 in the healthy eyes; all the involved individuals had no other ocular diseases except myopia and without any contraindications of MRI. Common tests including the best visual acuity, fundus test by direct or indirect ophthalmoscope, center static visual field tested by Octopus 101 perimeter, program 32, tendency oriented perimetry were performed. The visual stimulation subtended a field of view of about 12 degrees，consisted of high contrast and drifting checkerboards. MRI parameters: GE signa VH/i 30T scanner. Functional data: GRE-EPI sequence，20 slices lying perpendicular to the calcarine sulcus. Anatomical data was obtained using 3DSPGR sequence to acquire high resolution. The cortical surface was unfolded and then cut and inflated. Functional data was presented to the inflated surface and subsequently analyzed by AFNI software.Results In six eyes, three had temporal defects, two had upper temporal visual field defects, and the other one did not finish the visual field test. The retinotopic representations of health adults were obtained by using the phaseencoded visual stimulation. The Eccentricity coordinate maps showed that foveal representations lay in the occipital poles and the representations appeared further anterior as eccentricity increased. The polar angle coordinate maps showed that early retinotopically organized areas had a representation of visual field. The visual cortex beneath the calcarine sulcus matched with the upper visual field of the opposite side and which upon the calcarine sulcus matched with the under visual field of the opposite side. Less or no visual cortex response was revealed in the patients′ function MRI or the response in injury side was vanished. The visual cortex response related with the visual field defects could not be induced in function MRI.Conclusion There is a good correlation between function MRI data and the results of perimetric evaluation. The function MRI can show the visual cortex response correlated with the visual field defects of the patients with visual pathway diseases.
Functional imaging is a newly arisen interdisciplinary subject compared with the routine radiology displaying anatomy and morphology of lesions.It can exhibit the functionchanged information, such as blood flow and metabolism of organs and tissues as visual images or data to provide organizational functions and metabolic information, which makes early diagnosis, more accurate orientation, qualitative definition,and also the prognosis judgment.The ophthalmologists should pay more attention to the functional imaging applications in the field of neuro-ophthalmology.
ObjectiveTo investigate the CT and MR imaging features and distribution characteristics of lymphatic nodal involvement in patients with gallbladder carcinoma. MethodsThirtyseven histopathologically proven cases of gallbladder carcinoma with regional lymphatic nodal enlargement in upper abdomen were included into the study. The lymph nodal short diameter of equal to or larger than 10 mm was used as the criteria for positive lymphadenopathy. Thirtyone cases underwent contrastenhanced spiral CT scanning, 6 cases had MR imaging studies. CT and MR images were jointly evaluated by three radiologists with especial attention to the size and location of enlarged lymph nodes in upper abdomen.ResultsThe enlarged lymph nodes were observed in four anatomic locations in the upper abdominal region. ①The retroportal and retropancreatic group in which lymph nodes were located along the cystic duct and common bile duct, in the portocaval space and behind the pancreatic head. ②The celiac group in which enlarged nodes distributed along the common hepatic artery and surrounded the celiac trunk. ③The mesenteric group in which lymph nodes assembled at the mesenteric root and around the superior mesenteric vessels. ④The abdominal aorta group in which lymph nodes scattered at the left side of abdominal aorta and in the aortocaval space at the level of the left renal vein. The spiral CT visualization rates for the above 4 groups of lymphadenopathy were 89.1%(33/37), 78.3%(29/37), 29.8%(11/37) and 51.3%(19/37) respectively.ConclusionCT and MR can clearly depict the four location sites of lymphadenopathy in patients with gallbladder carcinoma, which closely reflects the three major lymphatic spreading pathways of gallbladder carcinoma, namely, the cholecystoretropancreatic, cholecystoceliac and cholecystomesenteric routes.
ObjectiveTo systematically review the diagnostic accuracy of MRI in preschool children with autism spectrum disorder. MethodsDatabases including Web of Science, PubMed, The Cochrane Library, EMbase, CBM, CNKI, WanFang Data, and VIP were electronically searched for studies on MRI in diagnosis of preschool children with autism spectrum disorder from inception to January 2022. Two reviewers independently screened the literature, extracted data, and assessed the risk of bias the included studies. Then, meta-analysis was performed using Meta-Disc, RevMan 5.4 and Stata 16.0 software. ResultsA total of 17 studies were finally included. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnosis odds ratio and area under the curve of SROC were 0.78 (95%CI 0.76 to 0.81), 0.77 (95%CI 0.75 to 0.79), 3.92 (95%CI 2.83 to 5.41), 0.28 (95%CI 0.23 to 0.35), 14.8 (95%CI 9.31 to 23.52) and 0.86, respectively. Subgroup analysis revealed that the source of patients, age, prediction methods and analysis features were potential sources of heterogeneity. Heterogeneity in the subgroup of 1-3 years old was small, and the pooled sensitivity, specificity and area under the curve of SROC were 0.81 (95%CI 0.76 to 0.85), 0.82 (95%CI 0.78 to 0.86) and 0.87, respectively. The pooled sensitivity, specificity and area under the curve of SROC for non-site studies were 0.80 (95%CI 0.75 to 0.84), 0.80 (95%CI 0.76 to 0.85) and 0.86, respectively. ConclusionMRI has a high accuracy in the diagnosis of preschool children with autism spectrum disorder; however, the possibility of misdiagnosis and missed diagnosis should be considered. Due to the limited quantity and quality of the included studies, more high-quality studies are needed to verify the above conclusion.
Objective To explore the program for calculating the necrotic articular surface area (NASA) and the ratio of NASA to whole articular surface area (WASA) of osteonecrosis of the femoral head (ONFH), to verify the accuracy of this calculation and to predict the collapse of the femoral head clinically using this program. Methods From June 2001 to June 2003, The specimens of the necrotic femoral head from eight patients (13 hips) were obtained by total hip arthroplasty. The magnetic resonance imaging (MRI) was taken in all patients before operation. According to a series of T1-weight pictures, the NASA and the ratio of NASA to WASA were calculated by designing program. The specimens of the necrotic femoral head were sawed into lays similar to MRI pictures using the coordinate paper stick on the auricular surface, the data processing were done by analytic instrument for pictures. The data of both were analyzed statistically by software SPSS 10.0 edition. The NASA and the ratio of NASA to WASA were calculated on MRI in ARCO Stage Ⅰ, Ⅱ 16 patients (25 hips) with non-operation. Follow-up was done to the patients with collapse of the femoral head and to the patients with no collapse for at least 24 months. The data were compared in collapse group and non-collapse group. Results There were no significant differences between MRI pictures calculation and specimens measurement (NASA: 0.412, ratio of NASA to WASA: 0.812, Pgt;0.05). Of the 25 hips followed up, collapse occurred in 17 hips. NASA was 31.06±8.10 cm2, (95% CI: 26.58 to 35.55)，the ratio of NASA to WASA was 58.91%±15.11%, (95% CI: 51.14to 66.68). No collapse appeared in 8 hips. NASA was 14.16±9.32 cm2(95% CI: 6.04 to 21.95), the ratio of NASA to WASA was 29.48%±19.76%(95% CI: 12.97to 45.99). The ratio in the patients with collapse was beyond 33%. Conclusion The NASA and the ratio of NASA to WASA in patients withONFH can be accurately calculated with the MRI pictures. The possibility of collapse can be predicted by this method. As it is complicated in operation, improvement should be made in order to put itinto clinical use.
【Abstract】Objective To compare radiologists’ performance on combined unenhanced and feridexs-enhanced MR imaging （MRI） with their performance on helical CT enhanced, unenhanced MRI, and feridexs-enhanced MR alone imaging for the characteristics of local hepatic lesions. Methods MR images and CT scans obtained in 26 patients with 57 local hepatic lesions were analyzed with reviewer operator characteristic (ROC) curve analysis. The imaging of patient were divided into 4 groups including combined unenhanced and feridexs-enhanced MRI group, helical CT enhanced group, unenhanced MRI group, and feridexsenhanced MR alone group. Results The combined approach resulted in larger area under the ROC curve (Az=0.926 0) and accuracy (86.8%),P＜0.05，as compared with the others methods. There were no significant differences among the other three methods. Conclusion Feridexs-enhanced MRI was more accurate than enhanced helical CT scan in characterization of local hepatic lesion. The combined analysis of unenhanced and feridexs-enhanced images was more accurate in the characterization of focal hepatic lesions than was review of feridexs-enhanced images alone.