ObjectiveTo summarize the status and progress of imaging studies of pancreatic neuroendocrine neoplasms (pNENs).MethodThe relevant literatures published recently at domestic and abroad about the imaging of pNENs were collected and reviewed.ResultsDue to poor visibility of pancreatic body and tail, the application of ultrasound (US) was limited. Compared with US, endoscopic ultrasound (EUS) and contrast-enhanced ultrasound (CEUS) could improve the detection rate of pNENs. The ability of plain CT scans to differentiate pathological grades was still controversial, but the value of enhanced scan was higher. CT texture analysis was feasible in the discrimination of nonhypervascular pNENs and pancreatic ductal adenocarcinoma (PDAC). Teta2 was the parameter with the highest diagnostic performance. The enhanced features of MRI were similar to CT. Combined with the apparent diffusion coefficient (ADC) value, the diagnostic and classification capabilities of MRI were improved, and the sensitivity and specificity of different ADC thresholds were also different. 68Ga-tetraazacyclododecane tetraacetic acid (68Ga-DOTA) peptide PET-CT had good preliminary diagnostic value for well-differentiated pNENs, and 18Fluoro-fluorodeoxyglucose (18F-FDG) PET-CT had limited diagnostic value.ConclusionsSomatostatin receptor imaging is of high diagnostic value and can guide clinical treatment and predict prognosis, but it has not been widely used in China. Conventional morphological images have advantages in the diagnosis and classification of pNENs. Therefore, it is important to choose a proper image inspection method.
Objective To investigate the diagnosis and effectiveness of surgical treatment for lumbar pyogenic spondyl itis. Methods Between February 2005 and June 2010, 15 cases of lumbar pyogenic spondyl itis were treated. There were 10 males and 5 females with an average age of 48.6 years (range, 26-72 years). Affected segments included L2, 3 in 3 cases,L3, 4 in 3 cases, L4, 5 in 8 cases, and L5, S1 in 1 case. All cases had cl inical manifestations of moderate or severe fever, local pain of lesion, and l imitation of the spinal movement; 10 patients had nerve root symptoms, and 8 patients had symptoms of lower limb paraplegia. Leukocyte, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) significantly increased in all cases. The preoperative X-ray and CT examinations showed no clear bone destruction; MRI showed decreased signal intensity on T1WI and increased signal intensity on T2WI, 7 cases had local ized abscess formation. The patients underwent focal cleaning and bone grafting and fusion combined with internal fixation, including anterior operation in 13 cases, posterior operation in 1 case, and combined anterior and posterior operation in 1 case. The results of bacterial culture were positive in 10 cases. According to the results of intraoperative bacterial cultures, sensitive antibiotics were selected. Results Healing of incision by first intention was achieved in 14 cases, healing by second intention in 1 case. After 2 weeks, 1 case recurred and symptoms was rel iefed after symptomatic treatment. Back pain and (or) lower limb pain were obviously improved in the other patients; body temperature recovered to normal after 3-4 days; leukocyte, ESR, and CRP significantly decreased. All the patients were followed up 12 to 70 months with an average of 35.4 months.The patients had no rejection, no fistula formation, no lumbar kyphosis, and no fixator loosening or breakage. The bony fusion time was 4-8 months. Conclusion Combination of cl inical manifestations, laboratory tests, and MRI can diagnose lumbar pyogenic spondyl itis, of which CRP is an important indicator to determine progression of the disease, and MRI is important for diagnosis. Debridement combined with interbody fusion and internal fixation is a safe and effective treatment method.
Objective To summarize the methods and applications for quantitative measurement of iron in human.Methods The methods and applications for quantitative measurement of iron in human were analyzed retrospectively via reviewing the literatures domesticly and abroad， and summarized the advantages and disadvantages respectively. Results The methods for quantitative measurement of iron included laboratory tests， pathology examinations， CT， superconducting quantum interference device investigation （SQUID）， and MRI. Conclusions Laboratory test is the most simple and economic method for quantitative measurement of iron in human. Percutaneous liver biopsy is the gold standardmethod. Radiologic examinations， especially MRI， may be main methods of measuring liver iron content in future.
Objective To evaluate the value of MRI in diagnosis of obstetrical brachial plexus palsy pre-gangl ionic injury. Methods From November 2006 to February 2008, 10 patients with obstetrical brachial plexus palsy were treated, 8 males and 2 females, aged from 2 months to 3 years (11.4 months on average). There were 7 cases of left side and 3 of right side.According to Tassin classification, 2 cases were type II, 6 type III and 2 type IV. All patients were performed MRI examinations before the operation, whose results were compared with those of exploration during the operation. Results MRI examinations showed 1 patient was normal and 9 patients had post-traumatic spinalmeningolcele. The 6 patients had displacement of spinal cord (4 towards the healthy side and 2 towards the sick side), 6 had deformity of spinal cord, and 2 had avulsed nerve root thickening. MRI detected 19 nerve roots were positive, 16 were true positive and 3 false positive in surgical exploration. MRI detected 6 nerve roots were negative, 4 were true negative and 2 false negative in surgical exploration. The sensitivity, specificity and accuracy of MRI in diagnosis of obstetrical brachial plexus palsy pre-gangl ionic injury were 84.2%, 80.0% and 83.3%, respectively. There were significant differences in the results by preoperative MRI examinations and by exploration during the operation (P lt; 0.05). Conclusion MRI can show pre-gangl ionic injury of brachial plexus of the patients with obstetrical brachial plexus palsy and can supply references for early diagnosis and operation time. MRI can be routinely conducted as a preoperative examination.
Objective To develop a modified short time inversion recovery (STIR) sequence grading system for lumbar intervertebral disc degeneration based on MRI STIR sequences, and to test the validity and reproducibility of this grading system. Methods A modified 8-level grading system for lumbar intervertebral disc degeneration based on routine sagittal STIR sequences and modified Pfirrmann grading system was developed. Between April 2011 and February 2012, 60 patients with different degrees of lumbar intervertebral disc degeneration were selected as objects of study, including 32 males and 28 females with an average of 50 years (range, 17-85 years). T2 weighted and STIR sequence images were obtained from the lumbar discs of L1, 2-L5, S1 of each object (total, 300 discs). All examinations were analyzed independently by 3 observers and a consensus readout was performed after all data collected. The validity and reproducibility were analyzed by calculating consistent rate and Kappa value. Results According to the grading system, there were 0 grade 1, 83 (27.7%) grade 2, 87 (29.0%) grade 3, 66 (22.0%) grade 4, 31 (10.3%) grade 5, 15 (5.0%) grade 6, 12 (4.0%) grade 7, and 6 (2.0%) grade 8. Intra-observer consistency was b (Kappa value range, 0.822-0.952), and inter-observer consistency was high to b (Kappa value range, 0.749-0.843). According to the consensus analysis, the total consistent rate was 82.7%-92.7% (mean, 85.6%). A difference of one grade occurred in 13.9% and a difference of two or more grades in 0.5% of all the cases. Conclusion Disc degeneration can be graded by using modified STIR sequence grading system, which can improve the accuracy of grading different degrees of lumbar intervertebral disc degeneration.
ObjectiveTo investigate the diagnostic value of spectral saturation inversion recovery, gradient-echo chemical shift MRI， and proton magnetic resonance spectroscopy in quantifying hepatic fat content. MethodsConventional T1-weighted and T2-weighted scanning (without fat saturation and with fat saturation)， gradient-echo T1W in-phase （IP） and opposedphase （OP） images and 1H-MRS were performed in 31 healthy volunteers and 22 patients who were candidates for liver surgery. Signal intensities of T1WI amp; T1WIFS (SInonfat1, SIfat1), T2WI amp; T2WI-FS (SInonfat2, SIfat2), and IP amp; OP (SIin, SIout) were measured respectively, the relative signal intensity one (RSI1), relative signal intensity two (RSI2)， and fat index (FI) were calculated. Peak values and the area under peak of 1H-MRS were measured, and the relative lipid content of liver cells (RLC ) were calculated. Twenty-two patients accepted liver resection and histological examination after MRI scanning, the proportion of fatty degenerative cells were calculated by image analysis software. Results①Hepatic steatosis group showed higher average values of RSI1, FI， and RLC to non-hepatic steatosis group (Plt;0.05), while there was no significant difference in RSI2 between two groups (Pgt;0.05). ②There was a statistical significant difference in RLC among different histopathological grades of hepatic steatosis, and RLC increased in parallel with histopathological grade (Plt;0.05).There was no significant difference in RSI2, RSI1, and FI among different histopathological grades, although the latter two had a tendency of increasing concomitant with histopathological grade (Pgt;0.05). ③The values of FI and RLC were positively correlated with the PFDC （r=0468, P=0.027； r＝0771， Plt;0.000 1）, while they were not in RSI1 and RSI2 (r=0.411, P=0.057； r=0.191, P=0.392). ConclusionsSPIR, Gradient-echo chemical shift MRI and 1H-MRS can help to differentiate patients with hepatic steatosis from normal persons, the latter also can help to classify hepatic steatosis. In quantifying hepatic fat content, 1H-MRS is superior to gradient-echo chemical shift MRI, while SPIR’s role is limited.
Objective To study the feasibility of virtual intercondylar notchplasty by applying MRI two-dimensional (2D) images to reconstruct three-dimensional (3D) images and measure the size of intercondylar notch. Methods Thirty healthy volunteers who had no knee joint disease and surgery history were selected. There were 15 females and 15 males with an age range of 20-30 years, weight range of 45-74 kg, and height range of 150-185 cm. They were divided into male group and female group, and the knees of each group were divided into 2 subgroups (the left group and right group). MRI scan of the left and right knees was performed, and the 2D images of MRI were imported into Mimics10.01 medical image control system for 3D reconstruction. The related anatomical data as follows were measured from the 3D digital model and analyzed by statistical software: notch width (NW), condylar width (CW), and notch width index (NWI). Then the 3D knee images of patients with anterior cruciate ligament (ACL) injury were collected between January and March 2010, and 4 patients with narrow intercondylar notch (NWI≤0.2) were selected for reconstructing the 3D model of the knee and simulating the intercondylar notch plasty. Then, the volume of osteotomy in 3D model was calculated and applied in the ACL reconstruction surgery, and whether the graft had impingement with intercondylar notch or not was evaluated. Results There were significant differences in NW and CW between male group and female group (P≤lt;≤0.05), but no significant difference was found in the NWI (P≤gt;≤0.05). And there was no significant difference in NW, CW, and NWI between the left and right knees both in male group and female group (P≤gt;≤0.05). After ACL reconstruction and intercondylar notchplasty, the shape of intercondylar notch became normal (NWI≤gt;≤0.22), no impingement occurred between the graft and intercondylar notch under arthroscopy within 3-month follow-up. Conclusion The shape of intercondylar notch of 3D model based on MRI 2D images is similar to the real intercondylar notch. NWI is one of important indexes which can reflect the narrow level of intercondylar notch. The virtual intercondylar notchplasty may provide preoperative plan and guidence for ACL reconstruction operation to avoid the impingement between graft and intercondylar notch after surgery.
Objective To systematically review the value of the perfusion paramenters of Ktrans and Kep of dynamic contrast enhanced MRI(DCE-MRI) in distinguishing different histological grades of rectal cancer. Methods Databases such as PubMed, EMbase, Web of Science, The Cochrane Library (Issue 1, 2017), CBM, CNKI, WanFang Data and VIP were searched from 1990 to Feb 6th, 2017 to collect the studies according to the criteria. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies and then meta-analysis was performed by using STATA 12.0 software. Results A total of 11 studies involving 618 patients were included. The results of meta-analysis showed that there was significant difference of Ktrans between poorly differentiated grade and moderately-well differentiated grade (SMD=1.123, 95% CI 0.334 to 1.911,P=0.005), but there was no significant difference of Kep between these two groups (SMD=0.233, 95% CI –0.173 to 0.639,P=0.260). Conclusion Current evidence shows that Ktrans can be used to distinguish different histological grades of rectal cancer. The clinical application value of Kep still needs large sample original studies to further verify.
Objective To investigate the situation of MRI examination in children in outpatient and inpatient departments of the Sichuan Provincial People’s Hospital from 2010 to 2012, so as to provide favourable basis for the choice of imaging examination in children. Methods The materials of electronic reports of MRI examination in paediatric inpatient and outpatient departments from 2010 to 2012 were collected, categorized, and analyzed. Results a) 2 148 children underwent MRI examination in the Sichuan Provincial People’s Hospital from 2010 to 2012. The total number of patients increased with year. Boys were more than girls. The positive incidence was slightly decreased. The number of outpatients was more than inpatients, but the positive incidence was lower in outpatients. b) The total numbers of examination position were increased with year and the number of single position examination was the most (accounted for than 85% of the total numbers). The main examination positions included: head, MRA of the head, cervical column, knees, lumbar column, pituitary gland, thoracic column, and abdomen. The examination positions diversified gradually. The application of examination technique also increased gradually. c) The systemic disease spectrum of positive cases in MRI examination included 9 categories, which accounted for 42.86% of ICD-10. The nervous systematic disease, muscle, skeleton and connective tissue disease were the categories. The major disease types were stable during the recent 3 years. The increase was obvious in injuries of the knees, malacosis and atrophy of the brain, the deformity of the brain. Conclusion The total numbers of the patients and positions examined increased gradually with year in the Sichuan Provincial People’s Hospital from 2010 to 2012. The applications of MRI in the head, limbs and joints, and soft tissues were more extensive. Children diagnosed as positive results had diseases of the central nervous system, limbs and joints, and connective tissue disease.
Objective To study the MRI diagnosis of sacral fracture with sacral neurological damage and its cl inical appl ication. Methods From October 1999 to October 2007, 20 cases of sacral fracture (Denis classification, Type II)with sacral neurological damage were examined by obl ique coronal MRI of sacrum to show the whole length of sacral nerve. There were 17 males and 3 females, aged 30-55 years. The time from injury to hospital ization varied from 1 day to 23 months. The injury was caused by traffic accident in 10 cases, smash of heavy object in 8 cases and crush in 2 cases. Eight cases were accompanied by pubis fracture and 4 cases by urethral disruption. All patients accepted the examination of X-ray, CT and spiral CT 3D reconstruction. X-ray showed the displacement of fracture fragment was backwards and upwards, and sacral-hole l ine was vague, asymmetric and distorted. CT showed that sacral neural tube was left-right asymmetry, the displacement of fracture fragment was backwards and upwards, combining with the compression and intruding to sacrum center at different section levels. The cl inical manifestations, international standards for Neurological Classification of Spinal Cord Injury recommended by American Spinal Injury Association International Spinal Cord Society, comparison between normal and abnormal MRI and Gierada’s results were the basis for cl inical diagnose and MRI diagnose, which was confirmed by operation. Results Nerve injury diagnosed by cl inical manifestation were S1 (17 cases), S2 (14 cases), S3 (7 cases), and S4 (6 cases). Nerve injury diagnosedby MRI were S1 (17 cases), S2 (14 cases), S3 (3 cases), and S4 (2 cases). Nerve injury confirmed by operation were S1 (17 cases), S2 (14 cases), S3 (7 cases), and S4 (1 case). Obl ique coronal MRI of sacrum showed the whole length of sacral nerve and its adjacent relationship, detecting bone fragment compression and route alteration of never were evident in 5 cases, the fat disappearance around the site of nerve root injury in 19 cases, narrowness of sacral nerve canal in 17 cases and the abnormally enlarged sacral nerve in 11 cases. Conclusion Obl ique coronal MRI of sacrum is of great value in the local ization and the qual itative diagnosis of sacral neurological damage.