T2 Mapping with and without Fat-Suppression to Predict Treatment Response to Intravenous Glucocorticoid Therapy for Thyroid-Associated Ophthalmopathy

Quantitative Analysis of Orbital Soft Tissues Using Three-Dimensional Fast Spin Echo With 2-Point Dixon-Based Fat Suppression Sequence: Its Association With Methylprednisolone Pulse Therapy Treatment Efficacy in Thyroid-Associated Ophthalmopathy

BACKGROUND

Three-dimensional fast spin echo with 2-point Dixon-based fat suppression (3D-FSE-Dixon) sequence may assess volume and water fraction (WF) of orbit.

PURPOSE

To explore the association between 3D-FSE-Dixon based parameters and methylprednisolone pulse therapy (MPPT) efficacy in active moderate-to-severe thyroid-associated ophthalmopathy (TAO).

STUDY TYPE

Retrospective.

POPULATION

Fifty-nine TAO patients (29 females, 30 males, 49.1 ± 10.9 years) were included: 26 (15 females, 11 males, 48.4 ± 11.1 years) showed improvement and 33 (14 females, 19 males, 49.6 ± 10.9 years) did not.

FIELD STRENGTH/SEQUENCE

3D-FSE-Dixon sequence of orbits at 3 T.

ASSESSMENT

Manual segmentation delineated bony orbit (BO), whole orbit (WO), globe (GO), lacrimal gland (LG), and optic nerve (ON). Multi-dimensional threshold (MDT) identified orbital fat (OF). Extraocular muscles (ETM) were obtained by subtracting other tissues from WO. WF was calculated from water and in-phase images. Treatment efficacy, the clinical outcome, was assessed within 2 weeks after MPPT.

STATISTICAL TESTS

Unpaired t-test and Mann-Whitney U test compared normal and non-normal data, respectively. Paired t-test analyzed parameter changes pre- and post-MPPT. Multivariate logistic regression analysis identified factors independently associated with the efficacy of MPPT. Significance was set at P < 0.05.

RESULTS

Responsive group showed significantly higher pre-treatment WF (ETM, 0.86 ± 0.06 vs. 0.82 ± 0.07; OF, 0.21 ± 0.04 vs. 0.19 ± 0.02), with no difference in volume (OF: 21.34 ± 3.33 vs. 21.36 ± 3.46, P = 1.00; ETM: 13.48 ± 2.82 vs. 13.72 ± 3.45, P = 1.00) or volume ratio (OF/GO: 3.23 ± 0.50 vs. 3.26 ± 0.56, P = 1.00; ETM/GO: 2.06 ± 0.58 vs. 2.12 ± 0.64, P = 1.00). WF significantly decreased in responsive group (ETM, 0.86 ± 0.06 vs. 0.79 ± 0.05; OF, 0.21 ± 0.04 vs. 0.17 ± 0.03) but not decreased in unresponsive group (ETM, 0.81 ± 0.07 vs. 0.81 ± 0.07, P = 1.00; OF, 0.19 ± 0.02 vs. 0.190 ± 0.02, P = 1.00). ETM WF and disease duration can assess MPPT efficacy.

DATA CONCLUSION

Higher ETM WF demonstrates better MPPT efficacy for TAO.

EVIDENCE LEVEL

4 TECHNICAL EFFICACY: Stage 4.

Fat-suppression T2 relaxation time and water fraction predict response to intravenous glucocorticoid therapy for thyroid-associated ophthalmopathy

OBJECTIVE

To investigate the value of fat-suppression (FS) T2 relaxation time (T2RT) derived from FS T2 mapping and water fraction (WF) derived from T2 IDEAL to predict the treatment response to intravenous glucocorticoids (IVGC) in patients with thyroid-associated ophthalmopathy (TAO) based on texture analysis.

MATERIALS AND METHODS

In this study, 89 patients clinically diagnosed with active and moderate-to-severe TAO were enroled (responsive group, 48 patients; unresponsive group, 41 patients). The baseline clinical characteristics and texture features were compared between the two groups. Multivariate analysis was performed to identify the independent predictors of treatment response to IVGC. ROC analysis and the DeLong test were used to assess and compare the predictive performance of different models.

RESULTS

The responsive group exhibited significantly shorter disease duration and higher 90th percentile of FS T2RT and kurtosis of WF in the extraocular muscle (EOM) and 95th percentile of WF in the orbital fat (OF) than the unresponsive group. Model 2 (disease duration + WF; AUC, 0.816) and model 3 (disease duration + FS T2RT + WF; AUC, 0.823) demonstrated superior predictive efficacy compared to model 1 (disease duration + FS T2RT; AUC, 0.756), while there was no significant difference between models 2 and 3.

CONCLUSIONS

The orbital tissues of responders exhibited more oedema and heterogeneity. Furthermore, OF is as valuable as EOM for assessing the therapeutic efficacy of IVGC. Finally, WF derived from T2 IDEAL processed by texture analysis can provide valuable information for predicting the treatment response to IVGC in patients with active and moderate-to-severe TAO.

CLINICAL RELEVANCE STATEMENT

The texture features of FS T2RT and WF are different between responders and non-responders, which can be the predictive tool for treatment response to IVGC.

KEY POINTS

Texture analysis can be used for predicting response to IVGC in TAO patients. TAO patients responsive to IVGC show more oedema and heterogeneity in the orbital tissues. WF from T2 IDEAL is a tool to predict the therapeutic response of TAO.

Application of Quantitative MRI in Thyroid Eye Disease: Imaging Techniques and Clinical Practices

Thyroid eye disease (TED) is a complex autoimmune disorder that impairs various orbital structures, leading to cosmetic damage and vision loss. Magnetic resonance imaging (MRI) is a fundamental diagnostic tool utilized in clinical settings of TED, for its accurate demonstration of orbital lesions and indication of disease conditions. The application of quantitative MRI has brought a new prospect to the management and research of TED, offering more detailed information on morphological and functional changes in the orbit. Therefore, many researchers concentrated on the implementation of different quantitative MRI techniques on TED for the exploration of clinical practices. Despite the abundance of studies utilizing quantitative MRI in TED, there remain considerable barriers and disputes on the best exploitation of this tool. This could possibly be attributed to the complexity of TED and the fast development of MRI techniques. It is necessary that clinical and radiological aspects of quantitative MRI in TED be better integrated into comprehensive insights. Hence, this review traces back 30 years of publications regarding quantitative MRI utilized in TED and elucidates this promising application in the facets of imaging techniques and clinical practices. We believe that a deeper understanding of the application of quantitative MRI in TED will enhance the efficacy of the multidisciplinary management of TED. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 3.

Prediction models of intravenous glucocorticoids therapy response in thyroid eye disease

Background

Thyroid eye disease (TED) is an autoimmune orbital disease, with intravenous glucocorticoid (IVGC) therapy as the first-line treatment. Due to uncertain response rates and possible side effects, various prediction models have been developed to predict IVGC therapy outcomes.

Methods

A thorough search was conducted in PubMed, Embase, and Web of Science databases. Data extraction included publication details, prediction model content, and performance. Statistical analysis was performed using R software, including heterogeneity evaluation, publication bias, subgroup analysis, and sensitivity analysis. Forest plots were utilized for result visualization.

Results

Of the 12 eligible studies, 47 prediction models were extracted. All included studies exhibited a low-to-moderate risk of bias. The pooled area under the receiver operating characteristic curve (AUC) and the combined sensitivity and specificity for the models were 0.81, 0.75, and 0.79, respectively. In view of heterogeneity, multiple meta-regression and subgroup analysis were conducted, which showed that marker and modeling types may be the possible causes of heterogeneity (P < 0.001). Notably, imaging metrics alone (AUC = 0.81) or clinical characteristics combined with other markers (AUC = 0.87), incorporating with multivariate regression (AUC = 0.84) or radiomics analysis (AUC = 0.91), yielded robust and reliable prediction outcomes.

Conclusion

This meta-analysis comprehensively reviews the predictive models for IVGC therapy response in TED. It underscores that integrating clinical characteristics with laboratory or imaging indicators and employing advanced techniques like multivariate regression or radiomics analysis significantly enhance the efficacy of prediction. Our research findings offer valuable insights that can guide future studies on prediction models for IVGC therapy in TED.

Predicting glucocorticoid effectiveness in thyroid eye disease: combined value from serological lipid metabolism and an orbital MRI parameter

Purpose

The aim was to determine the combined value of serological lipid metabolism and an orbital MRI quantitative parameter in predicting the effectiveness of glucocorticoid (GC) therapy in patients with thyroid eye disease (TED).

Methods

This study retrospectively enrolled 46 patients with active and moderate-to-severe TED (GC-effective group, n = 29; GC-ineffective group, n = 17). Serological lipid metabolism, the orbital MRI-based minimum signal intensity ratio of extraocular muscles (EOM-SIRmin), as well as other clinical parameters before GC therapy were collected and compared between the two groups. Multivariate logistic regression and receiver operating characteristic curve analysis were adopted to identify independent predictable variables and assess their predictive performances.

Results

Compared to the GC-ineffective group, the GC-effective group showed lower serum total cholesterol levels (P = 0.006), lower serum low-density lipoprotein cholesterol levels (P = 0.019), higher EOM-SIRmin values (P = 0.005), and shorter disease durations (P = 0.017). Serum total cholesterol and EOM-SIRmin were found to be independent predictors of GC-effective TED through multivariate analysis (odds ratios = 0.253 and 2.036 per 0.1 units, respectively) (both P < 0.05). The integration of serum total cholesterol ≤4.8 mmol/L and EOM-SIRmin ≥ 1.12 had a better predictive efficacy (area under the curve, 0.834) than EOM-SIRmin alone, with a sensitivity of 75.9% and a specificity of 82.4% (P = 0.031).

Conclusion

Serological lipid metabolism, combined with an orbital MRI-derived parameter, was a useful marker for predicting the effectiveness of GCs in patients with active and moderate-to-severe TED.

Application of quantitative orbital analysis to assess the activity of Graves' ophthalmopathy

This study aimed to evaluate the diagnostic value of uptake ratios in the extraocular muscles (EOMs), lacrimal glands, and optic nerves to detect the inflammation activity of Graves' ophthalmopathy (GO) using quantitative analysis of 99m technetium (99mTc)-labeled diethylene triamine pentaacetic acid (DTPA) orbital single-photon emission computed tomography/computed tomography (SPECT/CT) images. The patients were categorized into an active stage (clinical activity score ≥ 3/7, n=23) or an inactive stage (clinical activity score < 3/7, n=38), based on their clinical activity score. The uptake ratio was manually determined by placing a region of interest within the area of highest uptake, as agreed upon by consensus, in the EOMs, lacrimal gland, and optic nerve on SPECT images corrected for CT attenuation. Patients with active GO exhibited significantly higher uptake ratios in the EOMs, lacrimal glands, and optic nerves compared to patients with inactive GO (all P < 0.01). These parameters have been proven effective in differentiating between active and inactive disease.

Magnetic Resonance Imaging in the Management of Thyroid Eye Disease: A Systematic Review

PURPOSE

MRI may potentially detect active thyroid eye disease prior to elevation of clinical activity score. We aimed to systematically review the existing literature pertaining to MRI thyroid eye disease and to assess the role of MRI in the diagnosis of thyroid eye disease.

METHODS

A Population, Intervention, Comparison, Outcome/Preferred Reporting Items for Systematic Reviews and Meta-Analyses selection criteria was applied to identify studies for inclusion published between the years 2000 and 2023.

RESULTS

Twenty-four articles were identified for inclusion in the systematic review. All included studies utilized MRI as the imaging modality. MRI sequences used included T2-weighted imaging in 87.5%, T1-weighted imaging in 54.2%, diffusion-weighted imaging in 20.8%, and short tau inversion recovery in 16.7%. The most common parameters quantified were signal intensity ratio in 10 studies (41.7%) and T2-relaxation time in 8 studies (33.3%). Signal intensity ratio and T2-relaxation time were shown to correlate with clinical activity score and identify the phase of the disease.

CONCLUSIONS

MRI has untapped potential for further elucidating the highly complex biological processes in thyroid eye disease. As we move away from clinical activity score as a predictor of response to biologic therapy, MRI may prove more important than ever in the risk-benefit analysis around the use of immunomodulators.

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.