T2 magnetic resonance imaging mapping and morphology of the median nerve before and after surgery in carpal tunnel syndrome.

INTRODUCTION/AIMS: T2 magnetic resonance imaging (MRI) mapping has been applied to carpal tunnel syndrome (CTS) for quantitative assessment of the median nerve. However, quantitative changes in the median nerve before and after surgery using T2 MRI mapping remain unclear. We aimed to investigate whether pathological changes could be identified by pre- and postoperative T2 MRI mapping of the median nerve in CTS patients after open carpal tunnel release. METHODS: This was a prospective study that measured median nerve T2 and cross-sectional area (CSA) values at the distal carpal tunnel, hamate bone, proximal carpal tunnel, and forearm levels pre- and postoperatively. Associations between T2, CSA, and nerve conduction latency were also evaluated. RESULTS: A total of 36 patients with CTS (mean age, 64.5 ± 11.7 years) who underwent surgery were studied. The mean preoperative T2 values significantly decreased from 56.3 to 46.9 ms at the proximal carpal tunnel levels (p = .001), and from 52.4 to 48.7 ms at the hamate levels postoperatively (p = .04). Although there was a moderate association between preoperative T2 values at the distal carpal tunnel levels and distal motor latency values (r = -.46), other T2 values at all four carpal tunnel levels were not significantly associated with CSA or nerve conduction latency pre- or postoperatively. DISCUSSION: T2 MRI mapping of the carpal tunnel suggested a decrease in nerve edema after surgery. T2 MRI mapping provides quantitative information on the median nerve before and after surgery.

Role of feature tracking cardiac magnetic resonance imaging in early detection of cardiac dysfunction in ß-thalassemia patients recovered from COVID-19: A cross-sectional study.

Background and Aims: ß-Thalassemia patients may have cardiac complications due to iron overload, which puts them at higher risk of cardiac complications induced by coronavirus disease 2019 (COVID-19) compared with the normal population. The present study aims to evaluate early cardiovascular complications following iron overload in ß-thalassemia patients who had early recovery from COVID-19 by cardiac magnetic resonance imaging (MRI) and feature-tracking technique. Methods: Thirty-two confirmed COVID-19-recovered ß-thalassemia cases were evaluated within 3 weeks to 3 months after a positive reverse-transcriptase polymerase chain reaction COVID-19 test. Both the heart and liver of all patients were examined using cardiac MRI. Results: We analyzed 32 patients with mean age of 32.84 ± 6.45 years at baseline. Left ventricular global strain values were significantly associated with myocardial T2*. A cut-off value of -15.08% for global longitudinal strain (GLS) with sensitivity and specificity of 90% and 61.1% (p = 0.017), 32.33% for global radial strain (GRS) with sensitivity and specificity of 80% and 94.4% (p = 0.001) and -16.21 for global circumferential strain (GCS), with sensitivity and specificity of 80% and 89.9% (p = 0.013) may indicate cardiac iron overload. Conclusion: GLS, GRS, and GCS were significantly decreased in patients with myocardial T2* <20 ms (iron overload), while no significant change was observed in the right and left ventricular ejection fraction (RV- and LVEF). Cardiac MRI feature-tracking may be helpful in the early detection of cardiac complications resulting from iron overload in ß-thalassemia patients who had early recovery from COVID-19.

Quantitative assessment of anterior talofibular ligament quality in chronic lateral ankle instability using magnetic resonance imaging T2* value.

OBJECTIVE: To determine T2* normal reference values for anterior talofibular ligament (ATFL) and to investigate the feasibility of the quantitative ATFL quality evaluation in chronic lateral ankle instability (CLAI) using T2* values. MATERIALS AND METHODS: This study enrolled 15 patients with CLAI and 30 healthy volunteers. The entire ATFL T2* values from the MRI T2* mapping were measured. The prediction equation (variables: age, height, and weight) in a multiple linear regression model was used to calculate the T2* normal reference value in the healthy group. T2* ratio was defined as the ratio of the actual T2* value of the patient's ATFL to the normal reference value for each patient. A Telos device was used to measure the talar tilt angle (TTA) from the stress radiograph. RESULTS: T2* values of ATFL in the healthy and CLAI groups were 10.82 ± 1.84 ms and 14.36 ± 4.30 ms, respectively, which are significantly higher in the CLAI group (P < 0.05). The prediction equation of the normal reference T2* value was [14.9 + 0.14 × age (years) - 4.7 × height (m) - 0.03 × weight (kg)] (R2 = 0.65, P < 0.0001). A significant positive correlation was found between the T2* ratio and TTA (r = 0.66, P = 0.007). CONCLUSION: MRI T2* values in patients with CLAI were higher than those in healthy participants, and the T2* ratio correlated with TTA, suggesting that T2* values are promising for quantitative assessment of ATFL quality preoperatively.

Quantitative evaluation of lumbar facet arthritis-induced cartilage injury by MR T2* mapping / 中国组织工程研究

BACKGROUND:Lumbar facet arthritis is one of the main causes of low back pain.At present,MRI is mainly used for preliminary diagnosis,and there is still a certain probability of missed diagnosis and misdiagnosis.Therefore,MR T2* mapping imaging technology is expected to become an important means of quantitative detection of cartilage damage in lumbar facet arthritis. OBJECTIVE:To investigate the application value of MR T2* mapping imaging technique in quantitative analysis of cartilage damage and degeneration of lumbar facet joint. METHODS:A total of 110 outpatient or inpatient patients with low back pain in Fourth Affiliated Hospital of Nanjing Medical University from April 2020 to March 2022 were collected and set as case group.At the same time,80 asymptomatic volunteers were recruited as the control group.T2* mapping transectal images and T2WI images were obtained by 3.0T MR Scanning for the facet joints of all included subjects L1-S1.Weishaupt grading and T2* value measurement were performed for all facet joint cartilage,and the data were collected for parallel statistical analysis.The comparison of T2* values of facet joint cartilage between different articular Weishaupt grades was performed by one-way analysis of variance. RESULTS AND CONCLUSION:(1)Statistical analysis found that the T2* value of lumbar facet joint cartilage in the case group(17.6±1.5)ms was significantly lower than that in the control group(21.4±1.3)ms(P<0.05).(2)In the case group,with the hierarchical increase of lumbar facet joint Weishaupt,the T2*value of facet joint cartilage also showed a gradual decreasing trend,and the difference was statistically significant(P<0.05).(3)It is concluded that T2*mapping can better display the early pathological changes of lumbar facet joint cartilage injury,and T2* value of lumbar facet joint cartilage can quantitatively evaluate the degree of lumbar facet joint cartilage injury.T2* mapping imaging technique can provide a good theoretical basis for the imaging diagnosis of the early cartilage injury induced by lumbar facet arthritis and has important clinical application value.

The relationship of myocardial and liver T2* values with cardiac function and laboratory findings in transfusion-dependent thalassemia major patients: A retrospective cardiac MRI study.

Introduction: Cardiac complications are the leading cause of death in thalassemia patients. It is assumed that progressive iron accumulation results in myocyte damage. Myocardial T2* measurement by cardiac MRI quantifies iron overload. We aimed to study the association between left and right ventricular (LV and RV) function and iron deposition estimation by cardiac MRI T2* in a sample of Iranian patients. Methods: Cardiac MRI exams of 118 transfusion-dependent thalassemia major patients were evaluated retrospectively. Biventricular function and volume and myocardial and liver T2* values were measured. The demographic and lab data were registered. Poisson and chi-square regression analyses investigated the correlation between the T2* value and ventricular dysfunction. Results: The study participants' mean (SD) age was 32.7y (9.02), and 47.46% were female. Forty-nine cases (41.52%) revealed at least uni-ventricular dysfunction. LV dysfunction was noted in 20 cases, whereas 47 patients revealed RV dysfunction. The risk of LV dysfunction was 5.3-fold higher in patients with cardiac T2* value less than 10msec (RR=5.3, 95% CI=1.6, 17.1, P<0.05). No association was found between age, liver T2* value, serum ferritin level, and chelation therapy with the risk of LV and RV dysfunction. Conclusion: Cardiac MRI T2* measure is a good indicator of LV dysfunction. Moreover, MRI parameters, especially RV functional measures, may have a substantial role in patient management. Therefore, cardiac MRI should be included in beta-thalassemia patients' management strategies.

Role of T2 mapping of magnetic resonance imaging in the differentiation of endometrial cancer and benign endometrial lesions

PURPOSE: The T2 mapping of magnetic resonance imaging (MRI) in endometrial cancer (EC), benign endometrial lesions (BELs), and normal endometrium (NE) has rarely been reported. This study aimed to determine the T2 values of MRI in EC, BELs, and NE to investigate whether the T2 values can differentiate them and to assess the aggressiveness of EC. METHODS: In total, 73 patients [EC, 51 (age, 57.4 ± 5.4 years); BELs, 22 (age, 57.8 ± 11.8 years)] and 23 normal volunteers (age, 56.1 ± 6.6 years) were included. The T2 values of MRI of the EC (type I and II), BEL, and NE groups were described and compared. The relationships between the T2 values of MRI in EC and the pathological characteristics [International Federation of Gynecology and Obstetrics (FIGO) stage and grade] were analyzed. RESULTS: The median T2 values of NE, BEL, and EC were 197.5 (142.9-324.0) ms, 131.1 (103.2-247.9) ms, and 103.0 (71.6-243.5) ms (P < 0.001), respectively. The median T2 values of type I and type II EC were 100.8 (71.62-130.44) ms and 125.7 (119.7-243.5) ms, respectively. There were significant differences in the T2 values among the NE, BEL, type I EC, and type II EC groups (P < 0.001) except for between the type II EC and BEL groups (P = 0.938). The T2 value of MRI in type I EC was significantly lower than that in type II EC (P = 0.001). There were no significant differences in patients with type I EC having different FIGO stages (P = 0.273) or tumor grades (P = 0.686). CONCLUSION: T2 mapping of MRI has the potential to quantitatively differentiate between EC, BELs, and NE as well as between type I and type II EC.

Hip flexion angle affects longitudinal muscle activity of the rectus femoris in leg extension exercise.

PURPOSE: We investigated the effect of the hip flexion angle (HFA) on the longitudinal muscle activity of the rectus femoris (RF) during leg extension exercise (LEE). METHODS: We conducted an acute study in a specific population. Nine male bodybuilders performed isotonic LEE using a leg extension machine at three different HFAs: 0°, 40°, and 80°. Participants extended their knees from 90° to 0° at each HFA setting for four sets of ten repetitions at 70% of the one-repetition maximum. The transverse relaxation time (T2) of the RF was measured before and after LEE using magnetic resonance imaging. We analyzed the rate of change in the T2 value in the proximal, middle, and distal regions of the RF. The subjective sensation of muscle contraction of the quadriceps was measured using a numerical rating scale (NRS) and compared with the T2 value which was the objective index. RESULTS: At 80°, the T2 value in the middle RF was lower than that in the distal RF (p < 0.05). The T2 values at 0° and 40° HFA were higher than those at 80° HFA in the proximal (p < 0.05, p < 0.01) and middle RF (p < 0.01, p < 0.01). The NRS scores were inconsistent with the objective index. CONCLUSION: These results suggest that the 40° HFA is practical for region-specific strengthening of the proximal RF, and subjective sensation alone as an indication of training may not activate the proximal RF. We conclude that activation of each longitudinal section of the RF is possible depending on the hip joint angle.

Association of hepatic/pancreatic iron overload evaluated by quantitative T2* MRI with bone mineral density and trabecular bone score.

BACKGROUND: Iron-overloaded patients are recognized as presenting an increased risk of osteoporosis. However, studies on the correlation between osteoporosis and organ iron overload are controversial or scarce. The aim of this study is to assess bone mineral density (BMD) and trabecular bone score (TBS) in correlation with hepatic and pancreatic iron overload. METHODS: Forty-one patients diagnosed with hemoglobinopathies, were studied. BMDs of the lumbar spine (LS), femoral neck (FN), and total hip (TH) were analyzed by Dual-energy X-ray absorptiometry (DXA) scan. LS bone quality was derived from each spine DXA examination using the TBS analysis. Hepatic and pancreatic iron overload were obtained with a multi-echo gradient echo T2* technique. RESULTS: Abnormal microarchitecture and abnormal bone mass were observed in 19/41 (46.3%) and 9/41 (22.0%) patients, respectively. For 26 males, BMD, T-score and Z-score of LS were significantly lower among subjects with moderate-severe hepatic iron-overload than their counterparts, as it is between no- and pancreatic iron-overload groups. For 15 females, patients with moderate-severe hepatic iron-overload had significantly lower BMD and T-score of FN and TH, and patients with pancreatic iron-overload had significantly lower BMD, T-score of FN, and lower BMD, T-score and Z-score of TH than their counterparts. Moreover, pancreatic T2*-value was positively correlated with BMD and T-score at all analyzed sites and Z-score at TH. CONCLUSION: These data showed lower bone mass in patients with organ iron overload, particularly for LS in males, FN and TH in females. TBS may well represent a complementary tool for the evaluation of bone quality and the risk of fracture in iron-overloaded patients.

Evaluation of liver T1rho and T2 values in acute liver inflammation models using 7T-MRI.

PURPOSE: We measured the T1rho and T2 values the liver of acute liver inflammation model mice administered carbon tetrachloride (CCl4) after 3 days and 6 days after dispensed, and we compared and examined whether each relaxation time can be used for detect acute liver inflammation. METHODS: To create an acute liver inflammation model, a mixture of 0.2 ml / 100 g of CCl4 with an equal amount of Sesame Oil was administered once intraperitoneally to C57BL / 6JJmsSlc mice (n = 15). On the 3 days and 6 days after administration, we acquired T1rho mapping images and T2 mapping images of the liver under respiratory synchronization using for preclinical 7T-MRI, and we measured T1rho and T2 values and compared statistically. RESULTS: The liver T1rho value of control mice was 33.9 ± 2.5 ms before CCl4 administration, 43.2 ± 4.9 ms (p < 0.01) on the 3 days post CCl4 injection, and 41.0 ± 1.2 ms (p < 0.001) on the 6 days post CCl4 injection. The rate showed a significant increase of 27% on the 3 days after, as well as significant increase of 21% on the 6 days after. On the other hand, the liver T2 value of control mice was 26.7 ± 1.9 ms before CCl4 administration, 31.5 ± 3.4 ms (p < 0.05) 3 days post CCl4 injection, and 29.0 ± 2.0 ms (p = 0.06) 6 days post CCl4 injection. The rate 3 days after CCl4 administration showed a significant increase of 18%, after 6 days rate increased 9%, but no significant difference was confirmed compared with normal mice. CONCLUSIONS: The T1rho value changed significantly compared to the T2 value, and a continuous change was observed even after 6 days. T1rho mapping can diagnose acute liver inflammation.

Usefulness of T2 Relaxation Time for Quantitative Prediction of Meningioma Consistency.

BACKGROUND: Meningioma consistency is one of the most critical factors affecting the difficulty of surgery. Although many studies have attempted to predict meningioma consistency via magnetic resonance imaging findings, no definitive method has been established, because most have been based on qualitative evaluations. Therefore, the present study examined the potential of the T2 relaxation time (T2 value), a tissue-specific quantitative parameter, for assessment of meningioma consistency. METHODS: Eighteen surgically treated meningiomas in 16 patients were included in the present study. Preoperatively, the T2 values of all meningiomas were calculated pixel by pixel, and a T2 value distribution map was generated. A total of 27 tumor specimens (multiple specimens were procured if heterogeneous) were taken from these meningiomas, with each localization identified intraoperatively using image guidance. The consistency of the specimens was measured with a durometer, originally a device for measuring the hardness of material such as elastic rubber, and their water content was subsequently measured using wet and dry measurements. RESULTS: A significant correlation was found between the T2 values of the matched locations identified by image guidance intraoperatively and the consistency measured using the durometer (r = -0.722; P < 0.01) and the water content (r = 0.621; P = 0.01). In addition, the water content correlated significantly with the durometer consistency (r = -0.677; P < 0.01). CONCLUSIONS: The T2 values could be a reliable quantitative predictor of meningioma consistency, and the T2 value distribution map, which elucidated the internal structure of the tumor in detail, could provide helpful information for surgical resection.

Application value of magnetic resonance T2mapping in the diagnosis of knee osteoarthritis / 中国基层医药

Objective:To investigate the application value of magnetic resonance T2mapping in the diagnosis of knee osteoarthritis (KOA).Methods:The MRI data of the knees of 148 patients with KOA who underwent diagnosis and treatment between January 2017 and December 2020 in Benxi Central Hospital (KOA group) and 30 healthy volunteers (control group) were retrospectively analyzed. T2 values of cartilage in each sub-region of the knee were measured, grouped, and statistically analyzed.Results:There was no significant difference in the T2 value of cartilage in each sub-region of the knee between male and female patients in mild and severe KOA groups (all P > 0.05). T2 values in the medial anterior, middle, and posterior areas of the tibia, lateral anterior, middle and posterior areas of the tibia, medial middle, posterior and lateral areas of the femur, and lateral posterior area of the femur were (44.47 ± 2.35) ms, (46.52 ± 3.12) ms, (45.47 ± 2.40) ms, (43.68 ± 2.12) ms, (46.33 ± 3.36) ms, (43.92 ± 3.42) ms, (43.58 ± 2.40) ms, (45.53 ± 3.91) ms, (44.36 ± 3.15) ms, (46.41 ± 3.04) ms, respectively in the control group. They were (49.56 ± 2.05) ms, (51.67 ± 2.38) ms, (50.47 ± 2.53) ms, (48.68 ± 3.05) ms, (51.33 ± 4.62) ms, (48.92 ± 2.53) ms, (48.58 ± 3.15) ms, (50.53 ± 3.72) ms, (48.36 ± 2.41) ms, and (51.41 ± 3.64) ms, respectively in the mild KOA group, and (53.47 ± 2.46) ms, (56.52 ± 3.57) ms, (54.85 ± 2.89) ms, (52.68 ± 3.57) ms, (56.33 ± 3.91) ms, (52.92 ± 3.04) ms, (53.58 ± 3.36) ms, (55.53 ± 3.42) ms, (52.36 ± 4.13) ms, and (56.41 ± 3.56) ms, respectively in the severe KOA group. There were significant differences in abovementioned indices among the three groups ( F = 38.768, 39.412, 38.981, 40.432, 38.416, 38.635, 38.347, 40.712, 38.158, 39.418, all P < 0.05). Conclusion:The T2 value of knee cartilage in patients with KOA is unrelated to gender and related to the severity of the disease. Magnetic resonance T2 mapping can help diagnose KOA, and provide information about the changes in cartilage components of patients with early KOA.

Hidden brain iron content in sickle cell disease: impact on neurocognitive functions.

Children with sickle cell disease (SCD) are at a high risk for neurocognitive impairment. We aim to quantitatively measure cerebral tissue R2* to investigate the brain iron deposition in children and young adults with SCD in comparison to beta thalassemia major (BTM) and healthy controls and evaluate its impact on neurocognitive functions in patients with SCD. Thirty-two SCD, fifteen BTM, and eleven controls were recruited. Multi-echo fast-gradient echo sequence brain MRI was performed, and brain R2* values of both caudate and thalamic regions were calculated. SCD patients were examined for the neurocognitive functions. SCD had high iron overload 0.30 ± 0.12 mg/kg/day. 68.9% of SCD had under-threshold IQ, 12.5% had moderate to severe anxiety, and 60.8% had depression. There were no differences between SCD, BTM, and controls in brain MRI except that left thalamus R2* higher in BTM than both SCD and controls (p = 0.032). Mean right caudate R2* was higher in female than male (p = 0.044). No significant association between brain R2* and LIC or heart R2* values in SCD. Left caudate R2* directly correlate with age and HbS%, and negatively correlate with HbA% while right thalamus R2* negatively correlate with transfusion index and among SCD patients.Conclusion: Neurocognitive dysfunction in SCD could not be explained solely by brain iron overload. What is Known: • Children with sickle cell disease are at great risk of brain damage due to their irregularly shaped red blood cells that can interrupt blood flow to the brain. • There are a number of factors that have negative brain effects that result in learning difficulties, and this not only due to increase brain iron content. What is New: • Assessment of quantitative brain iron content using MRI R2* in children and young adults with SCD in comparison to beta thalassemia major and healthy controls. • Impact of brain iron content on neurocognitive functions of children and young adults with SCD.

Quantitative T2 mapping of rats with chronic hepatitis.

The aim of the study was to explore the diagnostic value of T2 mapping in an experimental rat model of chronic liver disease. Chronic hepatitis was induced in Sprague-Dawley male rats (n=88) by intraperitoneal and abdominal subcutaneous injection of carbon tetrachloride in olive oil. The normal control rats (n=12) were similarly injected with the same dose of normal saline. All rats were randomly selected and subjected to T2-weighted/spectral adiabatic inversion recovery and multiple gradient- and spin-echo sequence. After scanning, rats were sacrificed immediately and livers removed for staining with hematoxylin and eosin, as well as Masson's trichrome, to determine the pathological stage of hepatic fibrosis, necroinflammatory activity and steatosis. The T2 values were measured and associated with histopathological findings. The T2 values were significantly associated with hepatic fibrosis (P<0.05), but not with hepatitis (P>0.05) or steatosis (P>0.05). By partial correlation analysis, a significant positive correlation was observed between the T2 values and stages of liver fibrosis (r=0.820; P<0.05). T2 values increased with progressive hepatic fibrosis. The differences between T2 values and stages of liver fibrosis were statistically significant. Statistically significant differences were observed between different stages of liver fibrosis (P<0.05), with an area under the curve value of 0.944 for predicting stage F1 or greater, 0.942 for stage F2 or greater, 0.958 for stage F3 or greater, and 0.948 for F4. Thus, the T2 value is one of the quantitative indices of imaging and accurately reflects the stages of liver fibrosis.

MRI Quantitative Analysis of Eccentric Exercise-induced Skeletal Muscle Injury in Rats.

BACKGROUND: The aim of this study was to investigate the value of magnetic resonance (MR) quantitative analysis (MR-T2 mapping technique) for the evaluation of eccentric exercise-induced skeletal muscle injury. MATERIALS AND METHODS: We established an animal model of eccentric exercise-induced damage of Sprague Dawley rat skeletal muscle and evaluated the animals by MR imaging, determined the serum levels of fast skeletal troponin (fsTnI), and examined muscle histopathology, at 0, 1, 2, 4, and 7 days after eccentric exercise. The associations between MR imaging findings, and histopathological and laboratory results were evaluated. RESULTS: T2-weighted images (WIs) of quadriceps femoris muscles showed obvious high signal intensities after exercise, and the T2 values and serum fsTnI levels continued to increase, peaking at day 2 after exercise, p< 0.05. The histopathological findings in muscle specimens, which included swollen and ruptured cells, enlarged extracellular spaces, inflammation, and regeneration of muscle fibers, showed similar trends. After day 2, muscle specimens began to show evidence of self-repair, the T2WI signals decreased in intensity, and the T2 values and serum fsTnI levels decreased; however, at day 7 post injury, the values remained slightly higher than those in the control animals, p< 0.05. The T2 value was significantly correlated with the serum fsTnI level (r = 0.896, p< 0.01). CONCLUSION: T2 mapping technology accurately reflects the histopathological and fsTnI abnormalities and the degree of skeletal muscle damage associated with eccentric exercise followed by recovery. Because T2 mapping technology is noninvasive and can be quantitatively analyzed, it might become the preferred method for performing the diagnosis of eccentric exercise-induced skeletal muscle injury.

[The Effect of Scan Parameters on the Synthetic MRI].

Synthetic MRI can provide proton density (PD), T1 value, T2 value for each pixel by only one data acquisition and can create various contrast-weighted images. The aim of this study is to evaluate the effect on the calculation of the T1·T2 value when changing the scan parameters for synthetic MRI. In the phantom study, when changing 1st TE/2nd TE/TR/TSE factor, the effect on the T1·T2 value calculated by synthetic MRI was examined. In the volunteer study, the brain was imaged and compared with known T1·T2 value. In phantom study, the effect on the T2 value by the 1st TE/2nd TE/TSE factor was shown. In volunteer study, there was no problem in the calculated value of brain parenchyma. However, the T2 value of cerebrospinal fluid had the error of known value. The results show that it is necessary to set appropriate scan parameters on synthetic MRI.

With axial loading during MRI diurnal T2-value changes in lumbar discs are neglectable: a cross sectional study.

BACKGROUND: Axial loading during MRI (alMRI) combined with T2 mapping recently was shown as a promising method to reveal biomechanical intervertebral disc (IVD) characteristics. This feasibility study aims to investigate whether there is a diurnal variation in the IVD T2-value when using alMRI. This is of importance for the planning of when to perform alMRI investigations and for interpretations of alMRI findings in relation to clinical symptoms. METHODS: Six healthy volunteers (30 lumbar discs), were examined with alMRI at three different sessions during 1 day. To be representative for a low back pain cohort in terms of age and IVD degeneration the included participants had a wide age range (27-63y) and all Pfirrmann grades represented. The T2-values were measured in five IVD regions of interest (ROI). The ROIs were equally large in sagittal plane with ROI1 representing anterior parts of the IVD, ROI5 posterior IVD parts and ROI2-4 the parts in between. RESULTS: T2-values of the entire IVD varied between 38 and 138 ms at 7 am, 33-143 ms at 11.30 am, and 31-147 ms at 4 pm with large regional IVD variations at all time points. No significant alterations of the T2-values over the day were found, neither for the entire IVD (p = 0.4) nor for the various ROIs (p = 0.2-1.0). Neither when correlated to Pfirrmann grade, any significant diurnal T2-value changes were found. CONCLUSIONS: With alMRI, only minor diurnal T2-value changes were found in the lumbar discs. Nonsignificant and neglectable diurnal changes are advantageous both for research purposes, as well as in the clinical setting, giving comparable and robust data regardless of at what time-point the alMRI is performed.

The diagnostic application of fat quantification in the primary osteoporosis / 实用放射学杂志

Objective To investigate the change rules of the lumbar vertebral bone marrow fat fraction(FF)and T2* values at different bone mineral density(BMD)groups,and their relevances and the applications on the diagnosis of the primary osteoporosis. Methods The patients who underwent the dual energy X-ray absorptiometry(DXA)and the routine lumbar MRI scan,mDIXON-Quant scan were collected,and the BMD,T-score,FF and T2* values of L1-L4 were measured.According to the T-score,the vertebral bodies were divided into the normal group,the osteopenia group and the osteoporosis group.The differences of the FF,T2* values and BMD between each group were analyzed by one-way analysis of variance,and their correlations with BMD were analyzed by Pearson correlation,the diagnostic effects of them were evaluated by receiver operating characteristic curve(ROC curve).Results The differences of the FF ,T2 * values and BMD among the three groups were statistically significant (P < 0 .05) .The correlations of the FF and T2 * values with BMD were negative (r = - 0 .628 ,P < 0 .05 and r = - 0 .468 ,P < 0 .05 ,respectively) .The area under curve (AUC) of the FF and T2 * values were 0 .82 ± 0 .03 ,0 .79 ± 0 .03 ,respectively .Conclusion mDIXON-Quant which can accuratly quantify fat content could evaluate the lumbar vertebral bone marrow fat content ,reflect the changes of the bone quality ,provide valuable information for the diagnosis of osteoporosis ,and is helpful to predict the risks of the lumbar fragility fracture.

The Difference in Gender Affects the Pathogenesis of Ligamentum Flavum Hypertrophy.

INTRODUCTION: Gender differences may play a role in the pathogenesis of lumbar spinal stenosis. However, few reports that discuss the effects of gender differences in ligamentum flavum (LF) hypertrophy have been published, and no study has investigated the relationship between LF thickness and the quantitative value of intervertebral disc (IVD) degeneration. This study aimed to investigate the impact of gender on the pathomechanisms underlying LF hypertrophy, focusing on the relationship among LF thickness, IVD degeneration, and age. METHODS: The subjects include 100 patients with low back pain and leg numbness, tingling, or pain. We measured LF thickness and the T2 values of IVDs using MR imaging and analyzed the relationship among LF thickness, T2 values of IVDs, and age. The interclass correlation coefficient (ICC) was calculated as the inter-rater reliability between the LF thickness values measured by two investigators. RESULTS: ICC was calculated for the two measurements of LF thickness (r = 0.923, 95% CI: 0.907-0.936). No statistically significant difference in the T2 values of IVDs was observed between females and males from L2/3 to L5/S. There were significantly negative linear correlations between LF thickness and the T2 values of IVDs at all levels, but this correlation was not observed in females at L4/5. There were significantly negative linear correlations between age and the T2 values of IVDs from L2/3 to L5/S for all patients, females, and males (r = 0.422-0.756). In addition, there were significantly positive linear correlations between age and LF thickness from L2/3 to L4/5 for all patients (r = 0.329-0.361) and females (r = 0.411-0.481). Correlations were not observed for males at all levels or for all patients at L5/S. CONCLUSIONS: The relationships identified among LF thickness, age, and IVD degeneration suggest that gender differences play a role in the pathogenesis of LF hypertrophy.

Iron in deep brain nuclei in migraine? CAMERA follow-up MRI findings.

Introduction In the CAMERA population-based MRI study, migraineurs below the age of 50 had decreased T2-values indicative of increased iron deposition in several deep brain nuclei. Longer migraine history was associated with lower T2-values, suggesting an association between migraine attacks and iron accumulation. In the present nine-year follow-up study of the CAMERA cohort we re-measured the T2-values in deep brain nuclei to assess the evolution over time. Methods Baseline and follow-up T2-values measured in several basal ganglia of 128 participants (38 control, 90 migraine) were analyzed using quantitative T2 measurements and multivariate regression analysis. Results T2-values of most deep brain nuclei were increased - instead of an expected further decrease when only age-related iron accumulation would have played a role - compared to baseline (both among controls and migraineurs) and were not different in either group. In migraineurs, no differences were found by gender, migraine severity or subtype. Conclusion This study did not provide supportive data for migraine related increased iron accumulation in deep brain nuclei, but neither is it able to reject such hypotheses. Increased T2-values probably point at microstructural tissue changes that counteracted earlier accumulated iron effects. We hypothesize that, with aging, migraine-induced iron-related brain changes are obscured by other age-related tissue changes.

Hepatic T2 value in evaluation of HBV based acute-on-chronic liver failure / 中国医学影像技术

Objective To investigate the value of hepatic T2 value in evaluation of chronic HBV-related acute-on-chronic liver failure (HBV-ACLF).Methods The HBV-ACLF group,chronic hepatitis B group and control group who underwent liver MRI (M-GRASE sequence) were enrolled.The T2 map was produced from the post-processing software,and the mean T2 and R2 value of liver was calculated.The blood biochemical indexes from HBV-ACLF and chronic hepatitis B group were collected in 2 days pre-MR scaning.The differences of T2 and R2 values among 3 groups and the correlation between biochemical indexes and T2 value were analyzed.ROC curve was conducted to evaluate diagnostic efficiency of T2 value for HBV-ACLF.Results There were significant differences of T2value (x2 =19.074,P＜0.001) or R2 value (F=10.411,P＜0.001) among the 3 groups.The AUC of T2 value for diagnosing HBV-ACLF was 0.86 (P＜0.001),with the cut-off value 57.73 ms (R2=0.017).Moderate positive correlation was shown between T2 values and international normalized ratio (INR),prothrombin time (PT),haluronicacid (HA) values (rs =0.65,0.67,0.39,all P＜0.05),and moderate negative correlation was shown between T2 values and prothrombin activity (PTA),albumin (ALB),prealbumin (PA) values (rs =-0.67,-0.48,-0.37,all P＜0.05).Conclusion T2 or R2 value could reflect the liver function,and were correlated with some biochemical indexes,which illustrated a good diagnostic efficiency for diagnostic of HBV-ACLF.