Quality Evaluation of Temporomandibular Joint Images from 3 High-resolution Dynamic Sequences / 中国医学科学院学报

Objective To compare the image quality of three high-resolution dynamic MRI methods for evaluating the motion of temporomandibular joint disc and condyle. Methods Twenty-five patients with suspected temporomandibular joint disorders were examined by single-shot fast spin-echo (SSFSE),fast imaging employing steady-state acquisition (FIESTA),and spoiled gradient echo (SPGR) on the oblique sagittal position.Two radiologists performed subjective and objective evaluation on the images with double-blind method.The subjective evaluation included the signal intensity of mandibular condyle,articular disc,soft tissue around articular disc,and lateral pterygoid muscle,the contrast between articular disc and condyle,the contrast between articular disc and surrounding soft tissue,condylar motion,and disc movement.The objective evaluation indexes included image signal intensity,signal-to-noise ratio (SNR),and contrast-to-noise ratio (CNR).The subjective and objective indexes of the image quality were compared between the three sequences. Results The SSFSE sequence had lower signal intensity of articular disc and higher signal intensity of condyle and surrounding soft tissue than FIESTA and SPGR sequences (all P<0.001).The SPGR sequence showed higher signal intensity of lateral pterygoid muscle than the SSFSE and FIESTA sequences (P=0.017,P<0.001).Among the three sequences,SSFSE sequence showed the clearest articular disc structure (χ2=41.952,P<0.001),the strongest contrast between articular disc and condyle (χ2=35.379,P<0.001),the strongest contrast between articular disc and surrounding soft tissue (χ2=27.324,P<0.001),and the clearest movement of articular disc (χ2=44.655,P<0.001).SSFSE and FIESTA sequences showed higher proportion of disc displacement and reduction than SPGR sequence (all P<0.001).The CNR (χ2=21.400,P<0.001),SNR (χ2=34.880,P<0.001),and condyle signal intensity (F=337.151,P<0.001) demonstrated differences among SSFSE,FIESTA,and SPGR sequences.The CNR of SSFSE sequence was higher than that of FIESTA sequence (P<0.001),while it had no significant difference between SSFSE and SPGR sequences (P=0.472).In addition,the SSFSE sequence had higher SNR and signal intensity than FIESTA and SPGR sequences (all P<0.001). Conclusion The best image quality can be observed from SSFSE sequence where both the structure and movement of temporomandibular joint are well displayed.Therefore,SSFSE is preferred for the examination of temporomandibular joint movement.

Magnetic Resonance Imaging Anatomy of Alar Ligament: A Review of Literature

@#Alar ligament is one of the most important craniocervical junction (CCJ) ligaments; acting as stabilizer of CCJ and limiting axial rotation. It may be involved in various pathological processes including trauma. Magnetic resonance imaging (MRI) is increasingly being used in cervical spine trauma as a supplement to conventional radiography and computed tomography (CT) to detect a wide range of severe cervical spine injuries. MR depiction of alar ligament requires special sequences despite no known established MR sequence is available. However, the role of MRI in minor or moderate trauma, including whiplash injuries, has long been debated, particularly when neurological dysfunction is absent, because no anatomical disruption other than degenerative disc disease have been reported. In this review, we provide detailed account on the current knowledge of MR visualization of normal alar ligament; outlining the variations in its signal intensity, dimension, shape and orientation.

The evaluation value of MRI dynamic enhancement TIC combined with DWI in benign and malignant breast lesions / 中国医师杂志

Objective:To explore the clinical application value of dynamic contrast-enhanced MRI (DCE) time-signal intensity curve (TIC) combined with diffusion weighted imaging (DWI) in the diagnosis of benign and malignant breast lesions.Methods:This study was a retrospective study. 95 patients with suspected breast cancer who were diagnosed and treated in the Beijing Huairou Hospital from October 2018 to October 2021 were taken as the study subjects. All patients received DCE-TIC and DCE-DWI examinations, and then underwent needle biopsy after imaging examination. We evaluated the diagnostic efficacy of DCE-TIC and DCE-DWI alone and in combination in benign and malignant breast lesions by collecting general clinical data and apparent diffusion coefficient (ADC) values of patients, using pathological examination results as the " gold standard" .Results:A total of 95 patients with suspected breast cancer were diagnosed as benign lesions in 25 cases and malignant lesions in 70 cases after biopsy. Compared with benign lesions, the tumor diameter and ADC value of malignant lesions were significantly different (all P<0.05). The eceiver operating characteristic (ROC) curve of subjects was drawn, and the area under the curve (AUC) of DCE-DWI diagnosis of breast cancer was 0.826. 95 suspected breast cancer patients were diagnosed by DCE-TIC in 28 cases of type Ⅰ, 27 cases of type Ⅱ, and 40 cases of type Ⅲ. With the pathological diagnosis results as the " gold standard", the accuracy, sensitivity, and negative predictive value of DCE-TIC combined with DCE-DWI in the diagnosis of breast cancer were higher than those of a single diagnosis, with a statistically significant difference (all P<0.05); The specificity and positive predictive value of combined diagnosis were not statistically significant compared to single diagnosis (all P>0.05). Conclusions:Both DCE-TIC and DCE-DWI can differentiate benign and malignant breast lesions, and the accuracy, sensitivity, and positive predictive value of combined diagnosis are higher than those of single diagnosis. The combination of DCE-TIC and DCE-DWI can help improve the differential efficiency of breast lesion properties.

The value of gadoxetate disodium enhanced MRI in the quantitative assessment of liver fibrosis / 中华放射学杂志

Objective:To evaluate the value of quantitative analysis of the relative signal intensity (SI) of liver gadolinium disodium enhanced MRI in the grading of liver fibrosis.Methods:From January 2018 to October 2020, the relevant data of 131 patients who underwent gadoxetate disodium enhanced MRI examination were retrospectively analyzed in Henan Provincial People′s Hospital. All patients had histopathological results. According to the Laennec grading system of liver fibrosis, the patients were classified in F0-F1 (27 cases), F2 (19 cases), F3 (17 cases) and F4 (68 cases). The signal intensity of the liver, erector spinae and spleen were measured before and after the enhancement; and 5 post-contrast relative SI parameters were calculated, including the relative enhancement (RE), liver-to-muscle contrast ratio (LMC), liver-to-spleen contrast ratio (LSC), LMC increase rate, LSC increase rate. The differences of 5 post-contrast relative SI parameters among the different fibrosis grades were compared using one-way analysis of variance. The receiver operating characteristic (ROC) curves were drawn to evaluate the diagnostic efficacy of 5 post-contrast relative SI parameters in the diagnosis of clinically significant liver fibrosis (F2-F4), advanced liver fibrosis (F3-F4) and liver cirrhosis (F4).Results:The differences of RE, LMC, LSC, LMC increase rate, LSC increase rate among different liver fibrosis grades were statistically significant (all P<0.001). With the increasing of the degree of liver fibrosis, the RE, LMC increase rate and LSC increase rate showed decreased. ROC results showed that the area under the curve (AUC) of RE, LMC increase rate, LSC increase rate in diagnosing liver fibrosis in all levels were greater than those of LMC and LSC. The AUC values of RE, LMC increase rate, LSC increase rate in the diagnosis of significant fibrosis (F2-F4) were 0.89, 0.86, 0.83, with the sensitivity as 81.7%, 71.2%, 81.7%, and the specificity as 96.3%, 85.2%, and 74.1%, respectively. The AUC values of RE, LMC increase rate, LSC increase rate in the diagnosis of advanced liver fibrosis (F3-F4) were 0.93, 0.88, 0.86, with the sensitivity as 84.7%, 72.9%, 91.8%, and the specificity as 91.3%, 87.0 %, 71.7%; and the AUC values for diagnosing liver cirrhosis (F4) were 0.92, 0.86, 0.85, with the sensitivity as 82.4%, 76.5%, 92.7%, and the specificity as 88.9%, 81.0%, 65.1%, respectively. Conclusion:Gadoxetate disodium enhanced MRI relative SI parameters including RE, LMC increase rate and LSC increase rate might be used as a useful imaging marker in liver fibrosis grading.

Quantitative evaluation of lumbar spine osteoporosis by apparent diffusion coefficient and signal intensity ratio of magnetic resonance diffusion-weighted magnetic resonance imaging / 中国骨伤

OBJECTIVE@#To investigate the application value of apparent diffusion coefficient (ADC) and signal intensity ratio (SIR) of MR diffusion-weighted imaging (DWI) in quantitative evaluation of lumbar spine osteoporosis.@*METHODS@#A total of 175 patients with lumbar spine diseases who received dualenergy X-ray absorption (DXA) bone mineral density (BMD), routine MRI and DWI of the lumbar spine from May 2017 to October 2019 were selected. According to the T-value of DXA, the patients were divided into osteoporosis group (64 cases), osteopenia group (53 cases) and normal bone mass group (58 cases). The ADC and SIR values of L@*RESULTS@#There were statistically significant differences in ADC and SIR values among three groups (@*CONCLUSION@#ADC and SIR can better reflect the BMD of patients with lumbar diseases, and can quantitatively evaluate the vertebral body of osteoporosis, which play an important role in the diagnosis of lumbar osteoporosis.

MRI Signal Intensity Changes of Vertebral Bone Marrow

The main purpose of the article is to review the normal vertebral marrow and its appearance on MRI, including age-related changes and pathologic appearance based on routine MR sequences like T1, T2 & STIR. The signal intensity of the bone marrow depends mainly on the fat and water content. Each component has its appearance on MRI sequence that allows their differentiation. The red marrow is highly cellular, so it leads to a low signal intensity on T1-weighted sequences and high signal intensity on short tau inversion recovery (STIR) or fat-saturated T2-weighted sequences. Whereas, the yellow marrow presents an increased signal on T1- weighted sequences and low signal intensity on STIR or fat-saturated T2-weighted sequences. The differential diagnosis of pathological bone marrow includes degenerative changes, neoplasm, infection, and infiltrative marrow disorders. In this study, 30 cases were included, who presented with a chief complaint of neck pain, backache and radiculopathy who underwent MRI for evaluating the underlying pathology. The main objective of this study is to evaluate different MRI findings in these patients.METHODSPatients having neck pain, backache, and radiculopathy who presented in the Department of Radiodiagnosis at NRI Medical College and Hospital, Chinakakani, were included in the present study. On a random basis, 30 cases were included in the study, and all of them underwent routine MRI spine to a particular region according to the symptom.RESULTSThirty patients were studied with an age range of 22 years to 80 years. In our study, out of 30 patients, 4 had fatty replacement of marrow, 3 had hemangioma, 6 had Modic endplate changes, 3 had metastases, 4 had osteoporosis, 5 had Koch's spine, 5 had myeloproliferative disease. Of the 4 patients who had osteoporosis, two patients had wedge compression fractures.CONCLUSIONMRI is the sensitive tool in the imaging of vertebral marrow and imaging modality of choice in studying the bone marrow diseases. Routine sequences like T1, T2 & STIR sequences are the key for proper diagnosis and management of spinal pathology.

Value of quantitative MRI T2WI parameters in predicting surgical outcome of thoracic ossification of the ligamentum flavum / 中国组织工程研究

BACKGROUND: MRI has high sensitivity to thoracic myelopathy, which can assess the spinal cord injury by morphology and magnitude of cervical spinal cord compression. Additionally, it is a valuable tool for the prognosis evaluation of thoracic spinal stenosis. OBJECTIVE: To explore the value of quantitative MRI T2WI parameters in predicting surgical outcome of thoracic ossification of the ligamentum flavum, and to establish the prediction model of poor prognosis, so as to provide reference for prognosis evaluation. METHODS: From January 2010 to January 2019 at Cangzhou Central Hospital, clinical and imaging data of 87 cases of thoracic ossification of the ligamentum flavum treated by thoracic laminectomy were reviewed retrospectively. According to the JOA recovery rate at 6-month follow-up, the patients were divided into good recovery group (≥ 50%) and poor recovery group (< 50%). Age, sex, duration of disease, JOA score, Sato type of ossification, maximum spinal cord compression, cross-sectional area, distribution of hyperintense signal, signal intensity ratio, intramedullary signal size, local kyphosis, kyphosis correction, number of decompressed levels and incidence of cerebrospinal fluid were compared between two groups. Univariate analysis was used to analyze indicators with significant differences. Receiver operating characteristic curve was plotted to analyze prognosis. Areas under the curve and cut-off values were recorded. The independent predictors of poor recovery were estimated through multivariate logistic regression analysis and the prediction model was established. RESULTS AND CONCLUSION: (1) The duration of disease, JOA score, maximum spinal cord compression, cross-sectional area, signal intensity ratio and intramedullary signal size showed significant difference between good recovery and poor recovery groups (P < 0.05). (2) Receiver operating characteristic curve analysis showed that the area under the curve of the duration of disease, JOA score, maximum spinal cord compression, cross-sectional area, signal intensity ratio and intramedullary signal size was 0.670, 0.733, 0.647, 0.715, 0.753 and 0.765 respectively. The cut-off value was duration of 13 months, score 4, 29.8%, 0.25 cm2, 1.593 and 13.64 mm respectively. The duration of disease and maximum spinal cord compression had low discrimination power (the area under the curve < 0.7) in predicting poor recovery, whereas the JOA score, cross-sectional area, signal intensity ratio and intramedullary signal size had moderate discrimination power (the area under the curve 0.7-0.9). The area under the curve indicates good ability of signal intensity ratio and intramedullary signal size in combination (the area under the curve=0.791). (3) Logistic multivariate regression analysis showed that JOA score, cross-sectional area and combination of signal intensity ratio and intramedullary signal size were independent risk factors of poor recovery. A predicting model was built according to the result of the logistic regression analysis. It was shown that the area under the curve of this model was 0.890, which was significantly higher than that of the JOA score, cross-sectional area and combination of signal intensity ratio and intramedullary signal size (P < 0.05). (4) Combination of signal intensity ratio and intramedullary signal size had higher predictive ability than other MRI parameters. JOA score, together with quantitative MRI T2WI parameters may have a better predictive value for the risk of poor recovery in patients with thoracic ossification of the ligamentum flavum.

MRI Correlation with Functional Scores Following Anterior Cruciate Ligament Reconstruction Surgery

Introduction: An anterior cruciate ligament tear is the mostcommon ligament tear in the knee joint. Anterior cruciateligament reconstruction is an accepted intervention for noncoping anterior cruciate ligament injured subjects. The tornligament is removed from the knee before the graft is insertedin an arthroscopic procedure. Functional performance tests forassessing knee status is clearly evident in the literature, witheach task seen to place different demands on the knee jointunder controlled clinical conditions. MRI is able to asses graftsignal intensity in a non-invasive way. The intra-articular graftundergoes a maturation and remodelling process lasting evenbeyond 24 months due to synovial proliferation,vascularization, and “neoligamentization” of the graft.Materials & Methods: We did a descriptive cross-sectionalstudy of 30 patients with 1.5-T magnetic resonance imaging ofthe knee who had undergone anterior cruciate ligamentreconstruction six months after surgery. The amount of signalintensity changes in graft classified according to crosssectional area in axial sections as <25%, 25-50%, and >50 %.Patients were subjected to functional testing, post-surgery.Results: Of 30 cases examined increased intrasubstance graftsignal intensity was found in 73.3% (22 of 30) of patients onT2-weighted and intermediate weighted MR images. Therewas an insignificant association between graft signal intensityand functional tests.Conclusion: Graft signal intensity on can be seenafter ACL reconstruction and not necessarily correlate withlimitations in patients after ACL reconstruction surgery due tothe process of remodeling.

The value of MR T2WI signal intensity related parameters for predicting pathological complete response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer / 中华肿瘤杂志

Objective@#To evaluate the value of T2WI signal intensity related parameters that can be obtained by magnetic resonance imaging (MRI) for predicting pathological complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanved rectal cancer (LARC).@*Methods@#Signal Intensity of Tumor (SIT) and Signal Intensity of Tumor/Muscle (SIT/M) of MR T2WI before and after neoadjuvant chemoradiotherapy of 101 patients with locally advanced rectal cancer were evaluated by two experienced readers independently. Signal Intensity of Tumor Reduction Rate (SITRR) and Signal Intensity of Tumor/Muscle Reduction Rate (SIT/MRR) were calculated. The difference of related parameters of T2WI tumor signal intensity between the pCR and the non-pCR group were analyzed. Receiver operating characteristic (ROC) analysis was used to assess the diagnostic performance for predicting pCR.@*Results@#Of the 101 patients, 18 were in pCR group and 83 were in non-pCR group. In all patients, the SITpre, SITpost, SITRR, SIT/Mpre, SIT/Mpost and SIT/MRR measured by reader 1 were 197.0 (133.0), 144.2 (69.7), 0.4% (0.5%), 2.6 (0.6), 3.0 (2.3) and 0.4 (0.2)% in pCR group, and 227.0 (99.0), 205 (95.4), 0.1% (0.6%), 2.6 (0.6), 2.6 (1) in non-pCR group, respectively. SITpre, SITpost, SITRR, SIT/Mpre, SIT/Mpost and SIT/MRR measured by reader 2 were 193.0 (135.0), 143.0 (69.8), 0.4% (0.2%), 2.6 (0.6), 1.5 (0.5) and 0.39% (0.2%) in pCR group, and 234.0(108.0), 203(96.5), 0.1% (0.3%), 2.6 (0.6%), 1.7 (0.7) and 0.25% (0.2%) in non-pCR group, respectively. Between the pCR and non-pCR group, there were significant differences in SITpost, SIT/Mpost and SIT/MRR measured by both readers (all P<0.01), but there was no significant differences in SITpre and SIT/Mpre (P>0.05). The difference of SITRR measured by reader 1 was not statistically significant (P=0.415), while the difference of SITRR measured by reader 2 was statistically significant (P=0.001). In patients with rectal non-mucinous adenocarcinoma, SITpost, SIT/Mpost, SITRR and SIT/MRR measured by two physicians were still statistically significant between the pCR and non-pCR group (all P<0.01), but SITpre and SIT/Mpre had no significant difference (P>0.05). ROC curve analysis showed that in all patients, the area under curve (AUC) of SITpost, SIT/Mpost and SIT/MRR for predicting pCR to neoadjuvant chemoradiotherapy in locally advanced rectal cancer was 0.694-0.762, the sensitivity was 68.2%-77.3%, and the specificity was 63.6%-77.3%. In rectal non-mucinous adenocarcinoma patients, the AUC, sensitivity and specificity was 0.704-0.764, 62.7%-78.9% and 66.2%-84.2%, respectively.@*Conclusions@#T2WI signal intensity related parameters are potential predictors for pCR in locally advanced rectal cancer after neoadjuvant chemoradiptherapy. The predictive value is higher in non-mucinous adenocarcinoma.

The value of MRI IDEAL technique in the etiological analysis of vertebral compression fracture / 实用放射学杂志

Objective To discuss the differential value of magnetic resonance asymmetric echo threeGpoint waterGfat separation technique (IDEAL)in benign and malignant vertebral compression fractures.Methods 48 cases of vertebral compression fractures patients (85 vertebrals)were performed conventional MRI and IDEAL scanning at 1.5T superconducting MR scanner (GE Brivo 355 MR system).25 benign and 23 malignant vertebral compression fracture cases were enrolled in this study.25 benign cases(42 vertebrals)included 8 pure traumatic fractures,16 osteoporosis and 1 tuberculosis respectively,while 23 malignant cases (43 vertebrals)included 22 metastases and 1 myeloma respectively.The signal intensity ratios(SIR)of the benign and malignant vertebral in waterGfat imaging and that of inGphase and outGphase (fatty signal intensity/water signal intensity and outGphase signal intensity/inGphase signal intensity respectively),and namely SIR were measured and calculated.SIR in the 4 groups were statistically analyzed.Results WaterGfat SIR of benign vertebral compression fracture was 0.67±0.19,whereas in malignant vertebral compression fractures was 0.14±0.07,and the difference was statistically significant (t＝1 2.6 2 ,P＜0.05 ).SIR of outGphase signal intensity/inGphase signal intensity of benign vertebral compression fracture was 0.52±0.25,whereas in malignant vertebral compression fracture was 0.83±0.07,and the difference was statistically significant (t＝－7.2 9 ,P＜0.05).Conclusion The SIR of malignant group is significantly lower than that of benign group in waterGfat imaging. whereas the SIR of malignant group is higher than that of benign group in inGphase and outGphase imaging.There is no overlap of SIR between benign and malignant in waterGfat imaging and inGphase and outGphase imaging.IDEAL technique has a high application value in the identification of benign and malignant vertebral compression fractures,which is worth popularizing.

Utility of white matter to gray matter signal intensity ratio in comatose patients treated by targeted temperature management after cardiac arrest: a preliminary study

OBJECTIVE: This study examined the efficacy of the white matter (WM) to gray matter (GM) signal intensity ratio (SIR) in predicting the clinical prognosis of cardiac arrest patients. METHODS: Thirty-one patients who were resuscitated from cardiac arrest and underwent brain magnetic resonance imaging (MRI) were investigated retrospectively. Thirty one subjects with normal brain MRI findings served as the controls. The signal intensities (SI) were measured on T2-weighted image (T2WI). The circular regions of measurement (2–10 mm²) were placed over the regions of interest, and the average signals in GM and WM were recorded in the caudate nucleus (CN), putamen, anterior limb of the internal capsule, corpus callosum (CC), and in the cortex and WM of the frontal lobe. Cerebral performance category (CPC) 1–2 were classified as a good prognosis, and CPC 3–5 were classified as a poor prognosis. RESULTS: Most combinations of the SIR of WM to GM and most SIs of GM, except the frontal cortex, were significantly different between the two groups. On the other hand, the SI of WM was insignificant between both groups. In receiver operating characteristic (ROC) curve analysis, the SIR of the CC to CN had an area under the ROC curve (AUROC) of 1.00 for a cut-off value of 1.59 (sensitivity, 100%; specificity, 100%), the SIR of the CC to putamen had also an AUROC of 1.00 for a cut-off value of 1.43 (sensitivity, 100%; specificity, 100%). CONCLUSION: The SIR of WM to GM measured on a T2WI is related to the neurological outcome after a cardiac arrest.

Study on the significance of intravoxel incoherent motion quantitative index combined with time-signal intensity curve in the early diagnosis of residual lesions in non-small cell lung cancer after argon-helium cryosurgery / 中华肿瘤杂志

Objective@#To study the application of intravoxel incoherent motion (IVIM) quantitative index combined with time-signal intensity curve (TIC) of dynamic contrast enhanced 3.0T magnetic resonance in the early precise diagnosis of residual lesions in non-small cell lung cancer (NSCLC) after argon-helium cryosurgery.@*Methods@#One hundred NSCLC patients who underwent argon-helium cryosurgery were collected and divided into the residual group (21 cases) and non-residual group (79 cases) according to the result of needle biopsy and follow-up. The apparent diffusion coefficient (ADC), slow apparent diffusion coefficient (sADC), fast apparent diffusion coefficient (fADC), fraction of fast apparent diffusion coefficient (ffADC) and TIC type of IVIM quantitative index between the two groups were compared at 7 days and 1 month after argon-helium cryosurgery, respectively. The diagnosis performance of each quantitative index was analyzed by receiver operating characteristic (ROC) curve and the best cut-off value was computed. The specificity and sensitivity of TIC types were calculated as diagnostic criteria. The diagnosis performance of IVIM quantitative index combined with TIC type was evaluated and compared with the conventional MRI and DWI.@*Results@#The differences of ADC, sADC and ffADC at 7 days and 1 month after argon-helium cryosurgery between the residual group and non-residual group were statistically significant (all P<0.05), in which the diagnosis performance of sADC and ffADC were better. The AUC of sADC and ffADC at 7 days after argon-helium cryosurgery were 0.861 and 0.895, the sensitivity were 81.0% and 90.5%, and the specificity were 77.2% and 73.4%, respectively. The AUC of sADC and ffADC at 1 month after argon-helium cryosurgery were 0.836 and 0.883, the sensitivity were 100.0% and 76.2%, and the specificity were 58.2% and 89.9%, respectively. The diagnosis performance of TIC type Ⅱ&Ⅲ was best. The sensitivity and specificity were 80.9% and 58.2% at 7 days after treatment, 85.7% and 62.0% at 1 month after treatment, respectively. At 7 days after treatment, the sensitivity and specificity of IVIM combined with TIC were 97.5% and 85.7%, while at 1 month after treatment, the sensitivity and specificity of IVIM combined with TIC were 97.5% and 90.5%, respectively. The diagnosis performance of IVIM quantitative index combined with TIC type was better than conventional MRI and DWI.@*Conclusion@#The combination of IVIM quantitative index and TIC type can be used in the early diagnosis of residual lesions after argon-helium cryosurgery for NSCLC, whose effect is better than conventional MRI and DWI.

The value of the signal intensity ratio of the extraocular muscle and the ipsilateral white matter of the MRI in the evaluation of the activity of thyroid-associated ophthalmopathy / 中华内分泌代谢杂志

Objective To investigate the quantitative value of the signal intensity ratio of extraocular muscle and ipsilateral white matter measured by MRI for the evaluation of activity in thyroid-associated ophthalmopathy. Methods A total of 129 patients and 245 eyeballs with thyroid-associated ophthalmopathy were enrolled in this study and this 245 eyeballs were set as thyroid-associated ophthalmopathy group(TAO group). There were 10 patients with newly diagnosed Graves'disease and in the same period and these 20 eyeballs were set as graves'disease group(GD group). 32 normal people from annual physical test excluded thyroid and eye diseases and their 64 eyes were selected randomly for the normal control group(NC group). The signal intensity of the extraocular muscle and the ipsilateral white matter on the MRI images were measured, while did exophthalmos and the width of the inner fat of eyeballs (FWs)measurements in the same time. Results SIR,FWs,and exophthalmos of TAO group were higher than those of the other 2 groups[SIRs:1.71(1.40,2.10)vs 1.26(1.22,1.34)and 1.23(1.14,1.32);FWs:8.04(6.70, 8.71)mm vs 6.16(4.86,7.08)mm and 6.93(6.41,7.65)mm,exophthalmos:20.10(18.56,22.15)mm vs 15.40(14.87,16.60)mm and 14.73(13.40,16.07)mm,all P<0.05]. The reference value of SIR establishing based on SIRs of NC group is less than 1.37. In total 129 TAO patients,55 patients(with 106 eyeballs)have a clinical activity score(CAS). Then,these eyeballs were grouped to activity and non-activity(grouped by CAS≥3),and the baseline group difference of these 2 groups was not statistically significant. The SIRs and exophthalmos of activity group were higher than the non-activity group[SIRs:1.70(1.45,2.33)vs 1.41(1.25,1.75); exophthalmos:(20.38 ± 2.40)mm vs(19.05 ± 3.70)mm,all P<0.05]. But the difference of FWs of these two groups was not statistically significant(P>0.05). The SIRs and CAS had a positive correlation(r=0.580,P=0.000),through the receiver operating characteristic curve(ROC)we get the best diagnostic performance of TAO activity when the SIR≥1.56(sensibility=65.6%,specificity=89.1%,AUC=0.815,P=0.000). Conclusion The signal intensity ratio of extraocular muscle and ipsilateral white matter may discriminate the activity of TAO early as a quantitative indicator, reflecting its efficacy,and is worth clinically generalizing.

Statistical Analysis of Relation of Manganese Sulfide Inclusion Area to Signal Intensity by Laser-Induced Breakdown Spectroscopy / 分析化学

Laser-induced breakdown spectroscopy (LIBS) was used for analysis of the distribution of S,Mn,Fe,Cr,Mo,Si,Al in a 34CrNiMo6 steel sample cut from a main shaft of wind driven generator.The MnS inclusion area in each ablation craters cover zone was extracted in the way of comparing the metallograph captured by optical microscopy before and after LIBS scanning ablation.The statistic relation between MnS inclusion area and signal intensity of S and Mn was analyzed.The result showed that the abnormal signal of S and Mn occurred at the same position with the existence of MnS inclusion,and their signal intensity showed linear relationship.The abnormal signal of S and Mn were triggered mainly by MnS inclusion.The statistic result also showed linear relationship between signal intensity and MnS inclusion area both for S and Mn.It was possible to determine the inclusion type,size and distribution by analyzing abnormal signal.A simplified ablation model was established to calculate the relation of S and Mn content to MnS inclusion area.The arithmetic result showed a linear relation between the content and MnS inclusion area both for S and Mn.The calculation confirmed the linear relationship between signal intensity and inclusion area observed in experiment.The linear relationship could be interfered by macro-segregation,micro-segregation,deviation in measuring inclusion area,and inclusion spatter in pre-ablation.

A cross-sectional study on the correlation between MRI signal for IPFP and knee osteoarthritis / 中南大学学报(医学版)

Objective:To investigate the correlation between MRI signal for infrapatellar fat pad (IPFP) and pathological changes in knee osteoarthritis (KOA),and to analyze the role of IPFP in the development of knee osteoarthritis.Methods:A total of 114 subjects (without special knee disease) were enrolled for this study.The intensity of MRI signal for IPFP was determined by fat-suppressed proton-density-weighted turbospin-echo magnetic resonance imaging.Based on the cartilage defects and osteophytes of knee joint,the subjects were divided into a KOA group and a control group.The difference of MRI signal for IPFP between two groups was analyzed.Results:After excluding the potential confounders of age,gender and BMI,the intensity of MRI signal for IPFP was positively correlated with defections in patellar,medial femur,lateral tibial or knee joint (OR 1.333 to 2.168,P 0.006 to 0.023);the intensity of MRI signal for IPFP was also positively correlated with osteophytes in patellar,medial femur,lateral tibial or knee joint (OR 1.309 tol.781,P 0.004 to 0.046);the intensity of MR/signal for IPFP in the KOA group was significantly higher than that in the control group (P=0.028).Conclusion:The increase in the density of MRI signal for IPFP is an imaging manifestation for knee degeneration.IPFP inflammation and endocrine abnormalities may play an important role in KOA.

Usefulness of different-b-value diffusion-weighted imaging in early cerebral infarction / 医疗卫生装备

Objective To investigate the usefulness of different-b-value diffusion weighted imaging (DWI) in patients with early cerebral infarction and obtain the optimal b value of early cerebral infarction.Methods DWI at b-value of 1,000,2,000,and 3,000 s/mm2 was performed for 40 patients within 72 h after the onset of stroke using a GE Signa HDx 3.0T MRI scanner.Post-processing was done by the DWI specific software Function Tool to gain signal intensity and mean apparent diffusion coefficient in the lesions center and the contralateral normal brain tissue,respectively.The sensitivity of conventional MRI and different-b-value DWI was calculated in the diagnosis of early cerebral infarction.Results In 40 patients with early cerebral infarction,the sensitivity of b-values of 1,000,2,000,and 3,000 s/mm2 (DWIb=1 000,DWIb=2 000,DWIb=3 000) and conventional MRI in the diagnosis of early cerebral infarction were 100％,97.5％,97.5％,72.5％,respectively.With b value increased,signal intensity and ADC value declined.Under the condition of different b values,signal intensity and ADC value were statistically significant in region of interest (P＜0.05).Conclusion DWI is superior to conventional MRI scan in monitoring early cerebral infarction.With the increase of b value,the sensitivity is the higher to hyperacute cerebral infarction,the signal contrast is obvious,while signal to noise ratio of the image reduces.It is suggested that brain tissue contrast and the sensitivity to the new cerebral infarction is more predictable on b value =1,000 DWI than on the other DWIs.

Differentiation of breast fibroadenoma from breast cancer in DCE-TIC platform type with MRI / 医学研究生学报

Objective Differentiation of breast fibroadenoma from breast cancer is of great importance. The purpose of the ar-ticle was to evaluate the diagnostic efficacy of magnetic resonance imaging(MRI) in the differentiation of breast fibroadenoma from breast cancer in DCE-TIC ( dynamic contrast enchancement-time intensity curve) platform type ( typeⅡ) . Methods Between March 2014 and May 2016, 64 patients were included in our study, 19 patients with breast fibroadenoma and 45 patients with breast cancer. All the patients underwent DCE-MRI ( dynamic contrast-enhanced magnetic resonance imaging) examination before operation. Morpho-logic characteristics, hemodynamic characteristics, EER ( early enhancement rate) and ADC ( apparent diffusion coefficient) values were calculated and statistically compared. Results Among 19 cases of breast fibroadenoma, 9 cases were round or ovoid, 8 cases are lobulated, 2 cases were irregular, 15 cases with clear boundary, 14 cases in mammary gland vascular enlargement, 2 cases of slowinflows, 4 cases of moderate inflows, 13 cases of rapid inflows, and the average ADC value was ( 1. 47 ± 0. 38) × 10-3 mm2/s. Low signal separation present in 11 lesions of fibroadenoma. Among the 45 cases of breast cancer, 17 cases were round or ovoid, 7 cases were lobulat-ed, 21 cases were irregular, 11 cases with clear boundary, 38 cases of mammary gland vascular enlargement, 1 case of slow inflows, 5 ca-ses of moderate inflows, 39 cases of rapid inflows, and the averageADC values was (0.98±0.40)×10-3mm2/s. The shape, (χ2=9.176), margin (χ2=16.452), EER(χ2=18.489) and ADC between breast fibroadenoma and breast cancer were of significantly difference. No significant difference was found in the increased and enlarged blood vessels. The success of ADC values in differentation of breast fibroadenoma from breast cancer was statistically significant( P<0.001), and the area under the curve(AUC)of the ROC, sensitivity and specificity of VE were 94.7% and 71.1%. Conclusion Breast fibroadenoma are in fast inflows in the early phase on the DCE-MRI, and there are differences in morphologic characteristics and mass enhancement ways between patients with breast fibroadenoma and breast cancer. Morphologic characteristics combined with inter-nal low signal separation contribute to the differentiation of breast fibroadenoma from breast cancer.

Correlation between Preoperative Magnetic Resonance Imaging Signal Intensity Changes and Clinical Outcomes in Patients Surgically Treated for Cervical Myeloradiculopathy

STUDY DESIGN: This was a single surgeon, single center-based retrospective study with prospective data collection. PURPOSE: To assess the correlation between T2-weighted magnetic resonance imaging (MRI) signal intensity (SI) changes and factors such as age, duration of symptoms, baseline modified Japanese Orthopedic Association (mJOA) score and to determine its prognostic value in predicting recovery after surgery. OVERVIEW OF LITERATURE: Whether intramedullary cord T2-weighted MRI SI changes can predict operative outcomes of cervical myeloradiculopathy remains debatable, with only a few prospective studies analyzing the same. METHODS: Forty-six consecutive patients who underwent cervical myeloradiculopathy were included and were followed up for an average of 1 year. Preoperative T2-weighted MRI SI grading was performed for all patients. The correlation between MRI SI changes and age, duration of symptoms, preoperative mJOA score, and mJOA score at 1-year follow-up were analyzed. RESULTS: Fifteen patients had single-level (21.73%) or double-level (10.86%) prolapsed discs; 54.34% had degenerative cervical spondylosis with canal stenosis or multilevel disc prolapse and 13.07% had ossified posterior longitudinal ligaments. The mean age was 56.17±9.53 years (range, 35–81 years). The mean baseline mJOA score was 10.83±2.58 (range, 6–16), which postoperatively improved to 13.59±2.28 (range, 8–17; p<0.001). There was a statistically significant correlation between mJOA score at 1 year and MRI T2 SI grading (p=0.017). CONCLUSIONS: Patients with longer symptom durations had high grades of intramedullary cord T2-weighted MRI SI changes. Age and preoperative neurological status were not significantly correlated with the existence of intramedullary cord SI changes. However, patients without or with mild and diffuse intramedullary cord T2-weighted MRI SI changes had better postoperative neurological recovery than those with sharp and focal SI changes.

The value of preoperative magnetic resonance imaging in predicting postoperative recovery in patients with cervical spondylosis myelopathy: a meta-analysis

This meta-analysis was designed to elucidate whether preoperative signal intensity changes could predict the surgical outcomes of patients with cervical spondylosis myelopathy on the basis of T1-weighted and T2-weighted magnetic resonance imaging images. We searched the Medline database and the Cochrane Central Register of Controlled Trials for this purpose and 10 studies meeting our inclusion criteria were identified. In total, 650 cervical spondylosis myelopathy patients with (+) or without (-) intramedullary signal changes on their T2-weighted images were examined. Weighted mean differences and 95g% confidence intervals were used to summarize the data. Patients with focal and faint border changes in the intramedullary signal on T2 magnetic resonance imaging had similar Japanese Orthopaedic Association recovery ratios as those with no signal changes on the magnetic resonance imaging images of the spinal cord did. The surgical outcomes were poorer in the patients with both T2 intramedullary signal changes, especially when the signal changes were multisegmental and had a well-defined border and T1 intramedullary signal changes compared with those without intramedullary signal changes. Preoperative magnetic resonance imaging including T1 and T2 imaging can thus be used to predict postoperative recovery in cervical spondylosis myelopathy patients.

Application of susceptibility weighted and perfusion weighted imaging techniques in diagnosis and grading of clear cell renal cell carcinomas / 第二军医大学学报

Objective To investigate whether the degree of intratumoral susceptibility signal intensity (ITSS) of susceptibility weighted imaging" (SWI) correlates with the transfer constant (Ktrans) of perfusion weighted imaging (PWI), and to assess their values in diagnosis and grading of clear cell renal cell carcinoma (ccRCC). Methods Thirty-six patients with pathologically confirmed ccRCC and Fuhrman grades (I W) underwent both 2D multi-breath-hold SWI and renal PWI examination. The degree of ITSS and the mean value of Ktrans were evaluated. Kruskal-Wallis test and one-way analysis of variance (ANOVA) were applied to compare the differences among the three groups (Fuhrman I, TJ and [TJ). Spearman correlation coefficient was used to determine the correlation between degree of ITSS and mean value of Ktrans. Receiver operating characteristic (ROC) curve analysis was performed to determine the diagnostic accuracy. Results The degrees of ITSS of Fuhrman grade I (8 patients), grade TJ (16 patients) and grade III (12 patients) were (1. 25 ± 0. 43), (1. 75 ± 0. 83) and (2. 20 ± 0. 75), with the Ktrans values being (0. 24 ± 0. 07)min-1, (0. 31 ± 0. 08)min-1 and (0. 34 ± 0. 07) min-1, respectively, statistical significances were found for both degrees of ITSS and Ktrans values among the three Fuhrman groups (χ2 = 6. 089, P< 0. 05, F=4. 116, P<0. 05). A positive correlation was found between the degree of ITSS and value of Ktrans (r = 0. 536, P< 0. 01). ITSS and value of KtransROC curve analysis was used to distinguish Fuhrman UJ vs T - II ccRCC, the optimal area under curves (AUCs), sensitivity and specificity were 0. 737, 80. 0%, 37. 5% and 0. 737, 90. 0%. 68. 8%, respectively. Conclusion Both the degree of ITSS and mean value of Ktrans can provide more pre-operative information of ccRCC, helping to make surgical plans and to predict the prognosis.