Application of Multiparameter Quantitative Magnetic Resonance Imaging in the Evaluation of Graves' Ophthalmopathy.

BACKGROUND: Assessment of the activity of Graves' ophthalmopathy (GO) is difficult. Existing methods need improvement. PURPOSE: Investigate the application of multiparametric magnetic resonance imaging (MRI) in GO. STUDY TYPE: Retrospective. POPULATION: A total of 235 GO patients (age: 38.8 ± 13.4 years; 90 male; 96 active patients). FIELD STRENGTH/SEQUENCE: Short-tau inversion recovery (STIR) fast spin echo, multiecho spin echo T2 mapping and 3D T1-weighted fast field echo sequences at 3.0 T. ASSESSMENT: Two physicians assessed the mean and maximum signal intensity ratio of extraocular muscles to white matter (SIR), T2 relaxation time (T2RT), extraocular muscle area (EMA), fat fraction (FF), retrobulbar fat volume (RFV), and extraocular muscle volume (EMV). Clinical activity score (CAS) â‰§ 3 was in active stage. STATISTICAL TESTS: The optimal cut-off point of diagnostic efficacy was selected using receiver operating characteristic (ROC) curve analysis and evaluated using area under the curve (AUC), compared using Student's t test, analysis of variance or Kruskal-Wallis H test. The correlation used Pearson correlation analysis. The discriminant equation used a binary logistic regression analysis. P < 0.05 was considered statistically significant. RESULTS: The SIRmean, SIRmax, T2RTmean, T2RTmax, EMA, and EMV in active GO patients were significantly higher than those in inactive and were positively correlated with CAS (r = 0.276, 0.228, 0.438, 0.388, 0.502, and 0333, respectively). The FFmax of active patients was significantly lower than that of inactive patients and was negatively correlated with CAS (r = -0.44). Logistic regression analysis indicated that T2RTmean was independently associated with GO active periods and had good diagnostic performance (area under ROC curve = 0.736, sensitivity 70.7%, specificity 69.3%). T2RTmean â‰§ 74.295 could be a diagnostic cut-off for judging GO activity (sensitivity 55.3%). CONCLUSION: SIR, T2RT, EMV, and FF can quantitatively assess the activity and severity of GO and can potentially provide a basis for clinical judgment and selection of treatment options. EVIDENCE LEVEL: 4. TECHNICAL EFFICACY: Stage 2.

Extraocular muscle volume index at the orbital apex with optic neuritis: a combined parameter for diagnosis of dysthyroid optic neuropathy.

OBJECTIVES: To evaluate the diagnostic performance of the extraocular muscle volume index at the orbital apex (AMI) and the signal intensity ratio (SIR) of the optic nerve in dysthyroid optic neuropathy (DON). METHODS: Clinical data and magnetic resonance imaging were collected retrospectively from 63 Graves' ophthalmopathy patients, including 24 patients with DON and 39 without DON. The volume of these structures was obtained by reconstructing their orbital fat and extraocular muscles. The SIR of the optic nerve and axial length of eyeball were also measured. The posterior 3/5 of the retrobulbar space volume was used as the orbital apex to compare parameters in patients with or without DON. Area under the receiver operating characteristic curve (AUC) analysis was used to select the morphological and inflammatory parameters with the highest diagnostic value. A logistic regression was performed to identify the risk factors of DON. RESULTS: One hundred twenty-six orbits (35 with DON and 91 without DON) were analyzed. Most of the parameters in DON patients were significantly higher than in non-DON patients. However, the SIR 3 mm behind the eyeball of the optic nerve and AMI had the highest diagnostic value in these parameters and are independent risk factors of DON by stepwise multivariate logistic regression analysis. Combining AMI and SIR had a higher diagnostic value than a single index. CONCLUSIONS: Combining AMI with SIR 3 mm behind the eyeball's orbital nerve can be a potential parameter for diagnosing DON. CLINICAL RELEVANCE STATEMENT: The present study provided a quantitative index based on morphological and signal changes to assess the DON, allowing clinicians and radiologists to monitor DON patients timely. KEY POINTS: The extraocular muscle volume index at the orbital apex (AMI) has excellent diagnostic performance for dysthyroid optic neuropathy. A signal intensity ratio (SIR) of 3 mm behind the eyeball has a higher AUC compared to other slices. Combining AMI and SIR has a higher diagnostic value than a single index.

Establishment of magnetic resonance imaging 3D reconstruction technology of orbital soft tissue and its preliminary application in patients with thyroid-associated ophthalmopathy.

OBJECTIVE: Effective management of thyroid-associated ophthalmopathy (TAO) requires precise identification of the disease activity period as it is responsive to immunosuppressive treatment. Quantitative evaluations of orbital soft tissue are useful for analysing disease stages. We aimed to establish a method for orbital soft tissue volume calculation based on magnetic resonance imaging (MRI) data using 3D reconstruction technology. Furthermore, we validated the accuracy and precision of this method and investigated volume differences between patients with TAO and healthy individuals. MATERIALS AND METHODS: Using Mimics software for 3D reconstruction based on orbital MRI data, we quantitatively measured orbital fat volume (FV) and extraocular muscle volume (MV) using a manual phantom, and in patients with TAO and healthy volunteers (n = 10 each). The phantom was made using a combination of butter and chicken muscle and 2 observers measured its volume. Volume calculations were compared to a previously established standard volume. One observer measured a typical TAO case 10 times to calculate intra-observer variability while 3 observers independently measured 10 patients with TAO each to calculate interobserver variability. Orbital soft tissue volumes between 10 patients with TAO and 10 healthy individuals were compared. RESULTS: The precision of calculations for the phantom between the 2 observers varied from -4.60% to -2.78% for FV and between -4.13% to 0.71% for MV. Mean differences among repetitive calculations were lower than 4%, except during measurement of MV, which was 5.84%. The intraclass correlation coefficient varied from 0.976 to 0.996. FV was 15.53 ± 3.06 mL in patients with TAO and 11.32 ± 1.68 mL(P = .001)in healthy individuals, while MV was 3.19 ± 0.82 mL in patients with TAO and 2.45 ± 0.57 mL(P = .030)in healthy individuals. CONCLUSIONS: This method of calculating orbital soft tissue volumes based on MRI data and 3D reconstruction is both reliable and accurate as it yielded significant differences in tissue volume between patients with TAO and healthy individuals.

Associations of Serum Iron Status with MAFLD and Liver Fibrosis in the USA: a Nationwide Cross-Section Study.

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a new terminology characterized by liver steatosis. Iron status is related to many metabolic diseases. However, the researches on the associations of serum iron status with MAFLD are limited. The objective of this study was to investigate the associations of serum iron status biomarkers with MAFLD and liver fibrosis. A total of 5892 adults were enrolled in the current cross-sectional study using the 2017-March 2020 National Health and Nutrition Examination Survey. Liver steatosis and liver fibrosis were defined by the median values of controlled attenuation parameter ≥ 274 dB/m and liver stiffness measurement ≥ 8 kPa, respectively. The multivariable logistic/linear regression and restricted cubic spline analysis were conducted. After adjusting for potential confounders, higher ferritin levels were associated with higher odds of MAFLD (OR 4.655; 95% CI 2.301, 9.418) and liver fibrosis (OR 7.013; 95% CI 3.910, 12.577). Lower iron levels were associated with a higher prevalence of MAFLD (OR 0.622; 95% CI 0.458, 0.844) and liver fibrosis (OR 0.722; 95% CI 0.536, 0.974). Lower transferrin saturation (TSAT) was associated with a higher prevalence of MAFLD (OR 0.981; 95% CI 0.970, 0.991) and liver fibrosis (OR 0.988; 95% CI 0.979, 0.998). Higher ferritin levels, lower iron levels, and TSAT were associated with a higher prevalence of MAFLD and liver fibrosis. This study extended the knowledge of modifying iron status to prevent MAFLD and liver fibrosis. More prospective and mechanism studies were warranted to confirm the conclusions.

MIF promotes Th17 cell differentiation in Hashimoto's thyroiditis by binding HVEM and activating NF-κB signaling pathway.

Hashimoto's thyroiditis is a typical thyroid autoimmune disease and Th17 cells are crucial in its development. In recent years, MIF (Macrophage Migration Inhibitory Factor) has been found to promote the secretion of IL-17A and the production and differentiation of Th17 cells. However, the specific mechanism of it remains unclear. Here, we found that the expression of MIF, IL-17A and HVEM (Herpes Virus Entry Mediator) were up-regulated in HT patients. The proportion of Th17 cells in peripheral blood mononuclear cells was positively correlated with the serum MIF protein level. We further found that the expression of HVEM and the phosphorylation level of NF-κB in peripheral blood mononuclear cells of HT patients were significantly increased. Therefore, we speculated that MIF promotes Th17 cell differentiation through HVEM and NF-κB signaling pathways. Further mechanism studies showed that MIF could directly bind to HVEM, and the stimulation of rhMIF in vitro could increase the expression of HVEM and activate NF-κB signaling pathways to promote Th17 cell differentiation. After blocking HVEM with HVEM antibody, the effect of MIF on Th17 cell differentiation disappeared. The results above show that the differentiation of Th17 cells is promoted by MIF combined with HVEM through NF-κB signaling pathways. Our research provides a new theory to the regulation mechanism of Th17 cell differentiation and gives hint to new potential therapeutic targets for HT.

Image quality and evaluation ability of magnetic resonance imaging techniques for thyroid-associated ophthalmopathy: Dixon fat-suppression technique vs. spectral attenuated inversion recovery.

Purpose: We aimed to compare two magnetic resonance imaging (MRI) techniques, Dixon and spectral attenuated inversion recovery (SPAIR) fat-suppression, in terms of image quality and suitability for evaluating thyroid-associated ophthalmopathy (TAO) lesion characteristics. Methods: This cross-sectional, retrospective study involved 70 patients with TAO (140 eyes) who underwent orbital coronal MRI examinations, including Dixon-transverse relaxation (T2)-weighted imaging (T2WI) and SPAIR-T2WI, between 2020 and 2022. We compared the fat-suppression quality and artifacts, noise (N), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), signal intensity ratio (SIR) of extraocular muscles (SIR-EOM) and lacrimal glands (SIR-LG), and TAO activity evaluation efficiency. Results: Dixon-T2WI showed a higher frequency of better subjective image quality and suitability for evaluating the characteristics of TAO lesions (65.7% vs. 14.3%) than SPAIR-T2WI. Fat-suppression quality and artifact scores were lower for Dixon-T2WI than for SPAIR-T2WI (p < 0.001). The N, SNR, and CNR values, EOM-SIR, and LG-SIR were higher for orbital coronal Dixon-T2WI than for SPAIR-T2WI (all p < 0.001). Clinical activity scores (CASs) showed positive correlations with SIR. The correlation between EOM-SIR and LG-SIR of orbital coronal Dixon-T2WI with CAS was higher than that of SPAIR-T2WI (0.590 vs. 0.493, all p < 0.001; 0.340 vs. 0.295, all p < 0.01). EOM-SIR and LG-SIR of Dixon-T2WI yielded a higher area under the curve than SPAIR-T2WI for evaluating TAO activity (0.865 vs. 0.760, p < 0.001; 0.695 vs. 0.617, p = 0.017). Conclusion: Dixon-T2WI yields higher image quality than SPAIR-T2WI. Furthermore, it has a stronger ability to evaluate TAO inflammation than SPAIR, with higher sensitivity and specificity in active TAO staging.

A Randomized Clinical Trial of Intravenous Methylprednisolone With 2 Protocols in Patients With Graves Orbitopathy.

CONTEXT: Intravenous glucocorticoid (IVGC) is an accessible and affordable treatment for Graves orbitopathy (GO); the 4.5-g protocol is well studied, but many details of treatment protocols need to be clarified. OBJECTIVE: To compare the efficacy and safety of weekly and monthly protocol of IVGC in GO. METHODS: A prospective, randomized, observer-masked, single-center clinical trial, followed up to week 24, at the third affiliated hospital of Southern Medical University; 58 patients with active and moderate to severe GO, aged 18-60 years old, who had not received relevant treatment were included. The intervention was weekly protocol or monthly protocol of IVGC; both received a cumulative dose of methylprednisolone 4.5 g and had a duration of 12 weeks. The overall effective rate, improvement of quality of life (QOL) and signal intensity ratio (SIR) were measured. RESULTS: There was no significant difference in the effective rate between the 2 groups at week 12 and week 24 (86.21% vs 72.41%, P = .195; 86.21% vs 82.61%, P = .441), there was no significant difference in the improvement of clinical activity score, exophthalmos, soft tissue involvement, diplopia, and QOL. At week 24, the mean SIR and maximum SIR of the 2 groups were lower than those before treatment, and there were no statistically significant difference between the 2 groups. There was no significant difference in the incidence of adverse events between the 2 groups (31.03% vs 27.59%, P = .773). CONCLUSION: The efficacy and safety of the 2 protocols are comparable; the monthly protocol could be used as an alternative to the weekly protocol.

Association of multiple blood metals with thyroid function in general adults: A cross-sectional study.

Introduction: Thyroid function has a large impact on humans' metabolism and is affected by iodine levels, but there is a scarcity of studies that elucidate the association between thyroid function and other elements. Methods: We performed a cross-sectional study on 1,067 adults to evaluate the associations of the common essential metals with thyroid function in adults living in an iodine-adequate area of China. Serum free thyroxine (FT4), free triiodothyronine (FT3), thyroid stimulating hormone (TSH), and blood metals (zinc, iron, copper, magnesium, manganese, and calcium) were measured. Further, the thyroid hormone sensitivity indexes, FT3:FT4 ratio, and thyrotropin T4 resistance index (TT4RI) were calculated. Linear regression, quantile g-computation, and Bayesian kernel machine regression methods were used to explore the association of metals with thyroid function. Results: We found that the TSH levels correlated with copper (negative) and zinc (positive). Iron and copper were positively associated with FT3 and FT4 levels, respectively. Iron (positive) and copper (negative) were correlated with the FT3:FT4 ratio. Furthermore, we found that manganese was inversely correlated with TT4RI, while zinc was positively correlated. Discussion: Our findings suggest that manganese, iron, copper, and zinc levels were strongly correlated with thyroid function, and patients with thyroid disorders are recommended to measure those metals levels.

Associations of metal profiles in blood with thyroiditis: a cross-sectional study.

Autoimmune thyroiditis (AIT) is increasingly common, and serological markers include thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb). To determine if selected metals influence thyroiditis antibody positivity, this cross-sectional study investigated associations between metals and thyroiditis antibody status. Healthy individuals (n = 1104) completed a questionnaire and underwent checkups of anthropometric parameters, thyroid function status, and levels of seven metals in blood (magnesium, iron, calcium, copper, zinc, manganese, and lead). Associated profiles of glyco- and lipid metabolism were also established. Logistic regression and restricted cubic spline (RCS) regression analysis were applied to adjudge associations between metals and TPOAb and TgAb status. It was found that, after adjusting for likely cofounding factors, participants with antibody positivity had significantly lower serum concentrations of magnesium and iron. When serum magnesium levels were analyzed in quartiles, the odds ratios of quartile 4 were 0.329-fold (95% confidence interval (CI): 0.167-0647) and 0.259-fold (95% CI 0.177-0.574) that of quartile 1 regarding TPOAb and TgAb positivity (P = 0.004, 0.003). After adjustment, the RCS analysis detected nonlinear associations between iron and TPOAb and TgAb positivity (P < 0.01, both). In stratified analyses, these associations regarding magnesium and iron remained for women of reproductive age, but not for postmenopausal women and men. We conclude that lower serum levels of magnesium and iron are associated with incremental positivity of thyroiditis antibodies and may be among the most important metals contributing to AIT in women of reproductive age.

Current insights of applying MRI in Graves' ophthalmopathy.

Graves' ophthalmopathy (GO) is an autoimmune disease related to Grave's disease (GD). The therapeutic strategies for GO patients are based on precise assessment of the activity and severity of the disease. However, the current assessment systems require development to accommodate updates in treatment protocols. As an important adjunct examination, magnetic resonance imaging (MRI) can help physicians evaluate GO more accurately. With the continuous updating of MRI technology and the deepening understanding of GO, the assessment of this disease by MRI has gone through a stage from qualitative to precise quantification, making it possible for clinicians to monitor the microstructural changes behind the eyeball and better integrate clinical manifestations with pathology. In this review, we use orbital structures as a classification to combine pathological changes with MRI features. We also review some MRI techniques applied to GO clinical practice, such as disease classification and regions of interest selection.

Development of a prognostic gene signature for hepatocellular carcinoma.

Accurate prediction of overall survival is important for prognosis and the assignment of appropriate personalized clinical treatment in hepatocellular carcinoma (HCC) patients. The aim of the present study was to establish an optimal gene model for the independent prediction of prognosis associated with common clinical patterns. Gene expression profiles and the corresponding clinical information of the LIHC cohort were obtained from The Cancer Genome Atlas. Differentially expressed genes were found using the R package "limma". Subsequently, a prognostic gene signature was developed using the LASSO Cox regression model. Kaplan-Meier, log-rank, and receiver operating characteristic (ROC) analyses were performed to verify the predictive accuracy of the prognostic model. Finally, a nomogram and calibration plot were created using the "rms" package. Differentially expressed genes were screened with threshold criteria (FDR < 0.01 and |log FC|>3) and 563 differentially expressed genes were obtained, including 448 downregulated and 115 upregulated genes. Using the LASSO Cox regression model, a prognostic gene signature was developed based on nine genes, IQGAP3, BIRC5, PTTG1, STC2, CDKN3, PBK, EXO1, NEIL3, and HOXD9, the expression levels of which were quantitated using RT-qPCR. According to the risk scores, patients were separated into high-risk and low-risk groups. In conclusion, the prognostic gene signature can be used as a combined biomarker for the independent prediction of overall survival in HCC patients. Moreover, we created a nomogram that can be used to infer prognosis and aid individualized decisions regarding treatment and surveillance.

Associations of phthalates with NAFLD and liver fibrosis: A nationally representative cross-sectional study from NHANES 2017 to 2018.

Objective: Although phthalates are common environmental pollutants, few studies have focused on the relationship of phthalates exposure with non-alcoholic fatty liver disease (NAFLD) or liver fibrosis, and especially, the alternative phthalates have been questioned in recent years about whether they are better choices. Thus, this study aimed to explore the associations of exposure to major phthalates or alternative phthalates with NAFLD and liver fibrosis. Methods: Data of 1450 adults from the National Health and Nutrition Examination Survey (NHANES) 2017-2018 were collected. The urinary metabolite concentrations of di-2-ethylhexyl phthalate (DEHP), diisononyl phthalate (DINP) and diisodecyl phthalate (DIDP) were detected. Controlled attenuation parameter (CAP) and median liver stiffness measurement (LSM) were acquired for quantitative diagnosis of NAFLD and liver fibrosis by vibration-controlled transient elastography. Multivariate logistic regression analysis and linear regression analysis were performed to examine the associations between phthalates and NAFLD and liver fibrosis. Results: After adjustment of the potential factors, the prevalence of NAFLD was significantly elevated among those in the fourth quartile of mono-(2-ethyl-5-carboxypentyl) phthalate (OR, 95%CI = 2.719, 1.296, 5.700, P = 0.016), mono (2-ethyl-5-hydroxyhexyl) phthalate (OR, 95%CI = 2.073, 1.111, 3.867, P = 0.037). No significant association was found between the alternative phthalates and NAFLD. The similar result was gained by linear regression analysis that MECPP was still significantly associated with Ln CAP (Q4 vs. Q1: ß, 95%CI = 0.067, 0.017, 0.118, P = 0.027). After adjustment for the same covariates, no significant association between phthalates and liver fibrosis was found in logistics regression analysis. Conclusions: All in all, higher prevalence of NAFLD is correlated with DEHP but not DINP or DIDP in American adults. There is no significant relationship between phthalates and liver fibrosis defined as LSM ≥ 8 Kpa. Nevertheless, further research is needed to provide evidence of causality.

The Association of Thyroid Nodules With Blood Trace Elements Identified in a Cross-Section Study.

Background: The association between occurrence of thyroid nodules (TNs) and trace elements detectable in blood are still inconclusive. The present study sought to determine the relationship between selected trace elements and TNs in the iodine-adequate area of Guangdong, China. Methods: A total of 1,048 participants from four communities were enrolled. A number of medical checkups were conducted to collect relevant data on anthropometric parameters, blood pressure, glucose blood levels and lipid profiles, as well as data on thyroid function, presence of thyroid autoantibodies, and trace elements. Presence of TN was diagnosed by ultrasonography. Results: Of the 1048 participants (49.5 ± 14.4 years old), 543 participants (51.8%) had TNs. Serum copper, magnesium and zinc levels are associated with the presence of TNs among healthy subjects. Subjects with higher levels of zinc, magnesium and copper had 1.23-fold, 1.04-fold, and 1.007-fold increased risks of the prevalence of TNs (P = 0.013, 0.017, and < 0.001, resp). Compared with the first quartile of copper content in serum, participants in the fourth quartile had the highest prevalence of TNs with an odds ratio of 8.90 (95% confidence interval (CI) 5.41, 14.94) among all participants. Women in the third quartile of magnesium level had a 1.86-fold (95%CI 1.05, 3.31) risk of the prevalence of TNs. Subjects in the highest quartile of zinc level had a 1.82-fold (95%CI 1.06, 3.16) risk of the prevalence of TNs in females. Conclusion: TNs were found highly prevalent in females in the investigated population from an iodine-adequate area of Guangdong, China. The imbalance of selected trace elements (copper, magnesium and zinc) in the body is related to the presence of TNs among healthy subjects. The observed correlation of copper on TNs warrants further studies.

Macrophage migration inhibitory factor in the pathogenesis of leukemia (Review).

Leukemia is a group of malignant diseases of clonal hematopoietic stem­progenitor cells and its pathological mechanisms remain to be elucidated. Genetic and epigenetic abnormalities, as well as microenvironmental factors, including cytokines, serve critical roles in leukaemogenesis. Macrophage migration inhibitory factor (MIF) has been presented as one of the key regulators in tumorigenesis, angiogenesis and tumor metastasis. This article focuses on the functional role of MIF and its pathway in cancer, particularly in leukemia. MIF/CD74 interaction serves prominent roles in tumor cell survival, such as upregulating BCL­2 and CD84 expression, and activating receptor­type tyrosine phosphatase ζ. Furthermore, MIF upregulation forms a pro­tumor microenvironment in response to hypoxia­induced factors and promotes pro­inflammatory cytokine production. Additionally, polymorphisms of the MIF promoter sequence are associated with leukemia development. MIF signal­targeted early clinical trials show positive results. Overall, these efforts provide a promising means for intervention in leukemia.

UHRF1 regulates the transcriptional repressor HBP1 through MIF in T acute lymphoblastic leukemia.

Macrophage migration inhibitory factor (MIF) has been confirmed as an oncogene in solid tumor development, and its overexpression causes cell proliferation in T acute lymphoblastic leukemia (T­ALL); however, the underlying mechanisms remain unclear. The overexpression of MIF promotes cellular transformation and proliferation, in part, through interaction with UHRF1. Nevertheless, overexpression of UHRF1 cannot upregulate MIF expression in T­ALL. New insights into MIF regulation in T­ALL are imperative to offer the opportunity for therapeutic intervention. In the present study, using RT­qPCR, western blot analysis, confocal microscopy and RNA sequence, we report the identification and validation of UHRF1 as a negative regulator of MIF, which functions to downregulate MIF expression by binding to the CATT repeat sequence of the MIF promoter. By contrast, HMG­box protein 1 (HBP1) functions as a positive regulator of MIF. Moreover, we demonstrated that HBP1 suppressive signaling is reduced by UHRF1 through promotion of the interaction between MIF and HBP1. MIF deficiency caused by UHRF1 knockdown resulted in enhanced apoptosis in T­ALL as compared with that caused by decreased MIF or increased HBP1 expression alone. These results identify UHRF1 as a key regulator of MIF transcription in T­ALL, although these transcription factors possess opposite regulatory functions. Thus, this mechanism may provide insight into how to effectively prevent MIF­dependent oncogenic activity. Finally, T­ALL mice possessing high HBP1 or low UHRF1 expression levels are associated with longer survival as compared with control mice, with UHRF1­knockdown mice living the longest. Taken together, these findings indicate that MIF and its regulators are potential treatment targets and biomarkers for the prediction of prognosis in T­ALL.

[Calculation of orbital fat volumes for determining treatment timing for thyroid- associated ophthalmopathy].

OBJECTIVE: To analyze the relationship between orbital fat volume and the progression and prognosis of thyroid- associated ophthalmopathy (TAO) and determine the optimal treatment timing for TAO. METHODS: The clinical data were collected from 35 patients (70 orbits) with a definite diagnosis of TAO between January, 2016 and December, 2016. The correlation between orbital fat volume and the clinical parameters was evaluated. We also analyzed the correlation of the signal intensity ratio (SIR) of the extraocular muscles with the clinical parameters. The orbital fat volume was compared between patients with TAO and 12 control subjects. RESULTS: The orbital fat volume was significantly correlated with the duration of TAO (r=0.480, P<0.01), but showed no significant difference between patients with a disease course within 6 months and those with a disease course of 6 to 12 months (P=0.084). The patients with a disease course beyond 12 months had a significantly greater orbital fat volume than those with a disease course of 6 months (P<0.01) or 6 to 12 months (P<0.05). The orbital fat volume was correlated with the degree of proptosis (r=0.622, P<0.01), and an increase of exophthalmos by 1 mm was associated with a total orbital volume increment of 0.88 mL. The clinical activity score was correlated with the SIR of the extraorbital muscles (r=0.536, P<0.01) and levels of anti-thyroid-stimulating hormone receptor antibody (r=0.416,P<0.01). The orbital fat volume was significantly greater in TAO patients than in the healthy individuals (P<0.01). CONCLUSION: In patients with TAO, the peak increase of orbital fat volume occurs one year after the disease onset. Measurement of the orbital fat volume combined with SIR of the extraorbital muscles can serve as an indicator for determining the optimal timing for intervention of TAO and helps in the evaluation of prognosis of the patients.

[A novel method for quantitative measurement of orbital fat volume based on magnetic resonance images].

OBJECTIVE: To establish a new method for rapid and quantitative measurement of orbital fat volume based on magnetic resonance imaging (MRI) data. METHODS: We collected MRI data from normalized mold and patients with the diagnosis of thyroid-associated ophthalmopathy (TAO). The cross-sectional areas of the orbital fat on each MR image slice were measured to calculate the fat volume on each slice and then the total orbital fat volume. We recorded the time for completing the measurement and assessed the precision, reliability, repeatability and interoperator variations of the results. RESULTS: This MRI data-based method allowed precise measurement of the orbital fat volumes with an absolute value of the mean percentage difference <1%. This method was fast and the results showed a good repeatability (with CVs <1%), a high reliability (ICC=0.996, 95%CI: 0.985-0.999) and a high interoperator concordance (95%CI of the Bland-Altman: -0.54-0.90). CONCLUSION: The novel method we established for orbital fat volume measurement is rapid, accurate, reliable and reproducible with a low learning cost for clinical use.