Is the measurement of inferior thyroid artery blood flow velocity by color-flow Doppler ultrasonography useful for differential diagnosis between gestational transient thyrotoxicosis and Graves' disease? A prospective study

A meta-analysis: elucidating diagnostic thresholds of peak systolic flow velocities in thyroid arteries for the discrimination of Graves' disease and destructive thyrotoxicosis

Objective

This meta-analysis examines peak systolic velocities (PSVs) in thyroid arteries as potential biomarkers for thyroid disorders, which includes treated and untreated Graves' disease(GD) and destructive thyrotoxicosis(DT).

Methods

A search across databases including PubMed, Google Scholar, Embase, and Web of Science identified studies assessing peak systolic flow velocity in the inferior thyroid artery (ITA-PSV) and superior thyroid artery (STA-PSV) diagnostic efficacy in GD and DT.And the search was restricted to publications in the English language.The analysis compared STA-PSV and ITA-PSV across patient groups, evaluating intra-group variances and synthesizing sensitivity and specificity data.

Results

The analysis covered 18 studies with 1276 GD, 564 DT patients, and 544 controls. The difference of STA-PSV between GD group, DT group and normal group and the difference of ITA-PSV were analyzed in subgroups, and there was no statistical significance between subgroups when comparing any two groups. Normal subjects displayed intra-group ITA-PSV and STA-PSV differences with established cut-off values of 20.33 cm/s (95% CI, 17.48-23.18) for ITA-PSV and 25.61 cm/s (95% CI, 20.37-30.85) for STA-PSV. However, no significant intra-group differences were observed in the STA-PSV and ITA-PSV cut-off values among groups with GD or DT. The combined cut-off values for these patient groups and normal subjects were 68.63 cm/s (95% CI, 59.12-78.13), 32.08 cm/s (95% CI, 25.90-38.27), and 23.18 cm/s (95% CI, 20.09-26.28), respectively. The diagnostic odds ratio(DOR) for these values was 35.86 (95% CI, 18.21-70.60), and the area under the summary receiver operating characteristic (SROC) curve was 0.91, with a sensitivity estimate of 0.842 (95% CI, 0.772-0.866).

Conclusion

PSVs in thyroid arteries are useful diagnostic tools in distinguishing DT from GD. A PSV above 68.63 cm/s significantly improves GD diagnosis with up to 91% efficacy. No notable differences were found between superior and inferior thyroid arteries in these conditions.

Utility of Colour Flow Doppler Ultrasonography to Differentiate Gestational Transient Thyrotoxicosis and Graves Disease in Pregnancy

Introduction

Accurate diagnosis of the etiology of thyrotoxicosis in pregnancy is important to guide appropriate treatment. The role of thyroid blood flow velocities by color Doppler to differentiate between Graves' disease (GD) in pregnancy and gestational transient thyrotoxicosis (GTT) is not well explored. This study evaluated inferior thyroid artery (ITA)-peak systolic velocity (PSV) as a marker for differential diagnosis of thyrotoxicosis in pregnancy.

Methods

Fifty-six pregnant patients with thyrotoxicosis (30 with GTT and 26 with GD) along with 30 age-matched healthy euthyroid pregnant subjects were enrolled. Thyroid ultrasound examinations and color Doppler was performed by an ultrasound scanner. The studies of the right and left ITAs were performed with Doppler, and the PSV and End diastolic velocity (EDV) values were obtained from the right and left ITA.

Results

The mean total T4 value in GD and GTT were almost similar (25.04 ± 2.43 vs 23.25 ± 2.81, P value = 0.14). Beta HCG levels were significantly higher in cases of GTT as compared to GD (152946 ± 26694 vs 120608 ± 21244 mIU/ml, P < 0.0001). The ITA-PSV and EDV in patients with GTT were significantly lower than those of pregnant patients with GD (right: 22.5 ± 6.8 and 8.3 ± 2.3; left: 22.97 ± 6.3 and 8.13 ± 2.01; P < 0.001). receiver-operating-characteristic (ROC) curve demonstrated an optimal cutoff value of mean right ITA-PSV of 35 cm/sec to differentiate GTT from GD during pregnancy, with 84.6% and 93.3% sensitivity and specificity.

Conclusion

Thyroid artery velocities can help to differentiate between GD and GTT. The cutoff point of mean ITA-PSV at 35 cm/s had an excellent value in differentiating between the two, with good sensitivity and specificity.

Duplex Hemodynamic Parameters of Both Superior and Inferior Thyroid Arteries in Evaluation of Thyroid Hyperfunction Disorders

Background

Thyrotoxicosis may be caused by Graves’ disease or destructive thyroiditis. Differentiation between causes of thyrotoxicosis is crucial as management will differ. ^99mTechnetium (Tc)-pertechnetate thyroid scintigraphy is currently the gold standard for this purpose, however, is expensive and uses ionizing radiation.

Objective

To evaluate the role of color flow Doppler Ultrasound (CDU) of the superior thyroid (STA) and inferior thyroid arteries (ITA) as an inexpensive, non-invasive tool that can aid in differentiating between Graves’ disease and thyroiditis and compare it with thyroid scintigraphy.

Methods

Sixty-nine patients with newly-diagnosed thyrotoxicosis and 30 controls were enrolled. Thyroid functions, thyroid scintigraphy, and CDU of STA and ITA with measurements of peak systolic velocity (PSV) and end diastolic velocity (EDV), were performed. According to thyroid scintigraphy results, patients were divided into two groups: 42 patients with Graves’ disease and 27 patients with thyroiditis.

Results

PSV and EDV of both STA and ITA were significantly higher in patients with Graves’ disease than thyroiditis (p-values <0.001). The STA-PSV had an equal sensitivity and specificity of 66.7%; cut-off value 76.57 cm/s, while those of STA-EDV were 73.8%, and 77.8% respectively; cut-off value 28.22 cm/s. ITA-PSV had a sensitivity and specificity of 76.2% and 77.8%, respectively; cut-off value 62.12 cm/s), while those of ITA-EDV were 78.6% and 77.8%, respectively; cut-off value 5.22 cm/s.

Conclusion

CDU parameters of the STA and ITA could be used as an alternative to thyroid scintigraphy for discriminating between Graves’ disease and thyroiditis.

Color Duplex Doppler US can Follow up the Response of Radioiodine in Graves' Disease by Evaluating the Thyroid Volume and Peak Systolic Velocity

PURPOSE

 The objective of this study was to prove the efficacy of Doppler ultrasonography (US-Doppler) in the follow-up of patients with GD treated with radioactive iodine.

METHODS

 97 patients (77 female and 20 male) with a mean age of 42 years (SD ± 15) and with prior diagnosis of GD were treated with radioiodine. In total, 88.5 % achieved euthyroidism or hypothyroidism after treatment. The study was documented before treatment and one, three, and six months after treatment with radioactive iodine (131I) by a single investigator. The volume, echogenicity, echotexture and vascularization of the glands as well as the peak systolic velocity (PSV) of the inferior thyroid arteries were evaluated and compared with the laboratory data.

RESULTS

 Thyroid volume and PSV had a statistically significant correlation with hormone levels (p < 0.05). The mean pre-dose therapeutic thyroid volume was 43.01 ± 3.88 cm³ and was 11.58 ± 11.26 cm³ 6 months after treatment. The mean PSV before 131I was 90.06 ± 44.13 cm/s and decreased significantly over time (p < 0.001). Six months after the therapeutic dose, the mean PSV was 32.95 ± 16.36 cm/s. However, the subjective parameters did not have a significant correlation with the normalization of the thyroid hormones.

CONCLUSION

 Doppler US was useful for monitoring the therapeutic response of GD patients after treatment with radioiodine by evaluating the thyroid volume and peak systolic velocity.

Mean peak systolic velocity of superior thyroid artery for the differential diagnosis of thyrotoxicosis: a diagnostic meta-analysis

BACKGROUND

Thyrotoxicosis is often caused by destructive thyroiditis (DT) or Graves' disease (GD), and a prompt and accurate differential diagnosis for thyrotoxicosis is needed as management strategy differs. A meta-analysis of published literature was performed to evaluate the diagnostic accuracy for differentiating GD from DT patients by the measurement of mean peak systolic velocity of superior thyroid artery (STA-PSV) using ultrasonography.

METHODS

The databases of Embase, Pubmed, Cochrane, Web of Science, Wanfang, and CNKI were retrieved without time limit to identify eligible studies. The statistical information and scientific quality were assessed and classified. The data were analyzed using Stata12.0 software.

RESULTS

A total of 11 studies with 1052 cases only from Asia were included. Meta-analysis results showed the pooled sensitivity and pooled specificity of STA-PSV by ultrasonography were 0.86 (95% CI, 0.80-0.90) and 0.93 (95% CI, 0.86-0.97) in distinguishing GD from DT, respectively, with the AUC of 0.94 (95% CI, 0.92-0.96) .

CONCLUSION

STA-PSV by ultrasonography is a useful diagnostic method in differentiating GD from DT. More studies from other countries are needed to further evaluate the accuracy of STA-PSV for the differential diagnosis of thyrotoxicosis.

Graves' disease and pregnancy

This section deals with the specificities of managing Graves' disease during pregnancy. Graves' disease incurs risks of fetal, neonatal and maternal complications that are rare but may be severe: fetal hyper- or hypothyroidism, usually first showing as fetal goiter, neonatal dysthyroidism, premature birth and pre-eclampsia. Treatment during pregnancy is based on antithyroid drugs alone, without association to levothyroxine. An history of Graves' disease, whether treated radically or not, with persistent maternal anti-TSH-receptor antibodies must be well identified. Fetal monitoring should be initiated in a multidisciplinary framework that should be continued throughout pregnancy. Neonatal monitoring is also crucial if the mother still shows anti-TSH-receptor antibodies at end of pregnancy or underwent antithyroid treatment. The risk of recurrence of hyperthyroidism in the weeks following delivery requires maternal monitoring. The long-term neuropsychological progression of children of mothers with Graves' disease is poorly known.