Accuracy and reliability of thyroid volumetry using spiral CT and thyroid volume in a healthy, non-iodine-deficient Chinese adult population

Influence of sex, age and thyroid function indices on dual-energy computed tomography-derived quantitative parameters of thyroid in patients with or without Hashimoto's thyroiditis

PURPOSE

To study the influence of sex, age and thyroid function indices on dual-energy computed tomography (DECT)-derived quantitative parameters of thyroid in patients with or without Hashimoto's thyroiditis (HT).

MATERIAL AND METHODS

A total of 198 consecutive patients who underwent DECT scan of neck due to unilateral thyroid lesions were retrospectively enrolled. Iodine concentration (IC), total iodine content (TIC) and volume of normal thyroid lobe were calculated. Influences of sex, age and thyroid function indices on DECT-derived parameters in overall study population, subgroup patients with, and those without HT were assessed using Mann-Whitney U test, Student's T-test, and Spearman correlation analyses, respectively, as appropriate.

RESULTS

HT group showed significantly lower IC and TIC, while higher volume than No-HT group (all p < 0.001). The volume was larger in male than that in female in overall study population and No-HT group (p = 0.047 and 0.010, respectively). There was no significant difference in any DECT-derived parameters between low (≤ 35 years) and high (> 35 years) age group in all three groups (all p > 0.05). TPOAb and TgAb correlated positively with IC and TIC, and negatively with volume in overall study population (all p < 0.05). TPOAb and TgAb also correlated positively with IC in HT group (p = 0.002 and 0.007, respectively).

CONCLUSION

DECT-derived parameters of thyroid differed significantly between patients with and without HT. Sex and thyroid function indices could affect the DECT-derived parameters. Aforementioned physiological factors should be considered when analyzing the DECT-derived parameters of thyroid.

Optimization of Thyroid Volume Determination by Stitched 3D-Ultrasound Data Sets in Patients with Structural Thyroid Disease

Ultrasound (US) is the most important imaging method for the assessment of structural disorders of the thyroid. A precise volume determination is relevant for therapy planning and outcome monitoring. However, the accuracy of 2D-US is limited, especially in cases of organ enlargements and deformations. Software-based "stitching" of separately acquired 3D-US data revealed precise volume determination in thyroid phantoms. The purpose of this study is to investigate the feasibility and accuracy of 3D-US stitching in patients with structural thyroid disease. A total of 31 patients from the clinical routine were involved, receiving conventional 2D-US (conUS), sensor-navigated 3D-US (3DsnUS), mechanically-swept 3D-US (3DmsUS), and I-124-PET/CT as reference standard. Regarding 3DsnUS and 3DmsUS, separately acquired 3D-US images (per thyroid lobe) were merged to one comprehensive data set. Subsequently, anatomical correctness of the stitching process was analysed via secondary image fusion with the I-124-PET images. Volumetric determinations were conducted by the ellipsoid model (EM) on conUS and CT, and manually drawn segmental contouring (MC) on 3DsnUS, 3DmsUS, CT, and I-124-PET/CT. Mean volume of the thyroid glands was 44.1 ± 25.8 mL (I-124-PET-MC = reference). Highly significant correlations (all p < 0.0001) were observed for conUS-EM (r = 0.892), 3DsnUS-MC (r = 0.988), 3DmsUS-MC (r = 0.978), CT-EM (0.956), and CT-MC (0.986), respectively. The mean volume differences (standard deviations, limits of agreement) in comparison with the reference were -10.50 mL (±11.56 mL, -33.62 to 12.24), -3.74 mL (±3.74 mL, -11.39 to 3.78), and 0.62 mL (±4.79 mL, -8.78 to 10.01) for conUS-EM, 3DsnUS-MC, and 3DmsUS-MC, respectively. Stitched 3D-US data sets of the thyroid enable accurate volumetric determination even in enlarged and deformed organs. The main limitation of high time expenditure may be overcome by artificial intelligence approaches.

Variation in thyroid volumes due to differences in the measured length or area of the cross-sectional plane: A validation study of the ellipsoid approximation method using CT images

PURPOSE

This study examined the variation in the thyroid volume determined by the ellipsoid approximation method due to differences in the measured length or area of the cross-sectional plane of CT images.

METHODS

Forty-five patients with Graves' disease were included in this retrospective study. We designated the three-dimensional thyroid volumes extracted manually (V_CT ) as the reference data and calculated five approximate volumes for comparison: (a) the mean volume of 8100 different thyroid volumes depending on the diameter of the cross-sectional plane at the midpoint of the major axis, (V_{ellipsoid,mean} ); (b) the volume using the maximum diameter and its orthogonal diameter, (V_{ellipsoid,maxlength} ); (c) the maximum (V_{ellipsoid,maxvolume} ); (d) minimum (V_{ellipsoid,minvolume} ) of the 8100 thyroid volumes; and (e) the volume determined with an equivalent circle diameter, (V_{ellipsoid,Heywood} ).

RESULTS

Thyroid volumes obtained via the ellipsoid approximation method varied depending on the diameter of the cross-sectional plane and included a mean error of approximately 20%, while the concordance correlation coefficient (CCC) differed for each approximate volume. Among these volumes, V_{ellipsoid,mean} and V_{ellipsoid,Heywood} were in good agreement with V_CT , according to single regression analyses and the resultant CCC values, with mean errors of 0.1% and 10.4%, respectively.

CONCLUSION

While V_{ellipsoid,Heywood} approximated thyroid volumes with vastly reduced errors, we recommend utilizing three-dimensional thyroid volumetry if measurement accuracy is required.

Iodine concentration and content measured by dual-source computed tomography are correlated to thyroid hormone levels in euthyroid patients: a cross-sectional study in China

Background

The aim of this study was to investigate the correlation of the dual energy CT measured iodine concentration and total iodine content with blood measured thyroid parameters.

Methods

Forty-three patients with normal thyroid function at our hospital from August 2017 to October 2019 were included in this retrospective study. Dual energy CT was used to scan the neck of thyroid patients. The mean iodine concentration and thyroid tissue volume were measured to calculate the total iodine content of the thyroid. Relevant tests of triiodothyronine (FT3), total triiodothyronine (TT3), total thyroxine (TT4), free thyroxine (FT4), and thyroid hormone (TSH) were conducted. The correlation of the thyroid mean iodine concentration and total iodine content with blood-measured thyroid function was analysed.

Result

The total iodine content in the thyroid was positively correlated with FT3 but negatively correlated with TSH. The mean iodine concentration of the thyroid was positively correlated with both FT3 and TT3.

Conclusion

The thyroid iodine content measured by dual energy CT can be used to determine the human iodine nutritional status and evaluate thyroid function, which will facilitate the diagnosis and treatment of thyroid diseases.

Volume Measurement in the Diagnosis of Mounier Kuhn Syndrome and an Unknown Accompanying Pathology: Pulmonary Artery Enlargement

BACKGROUND

Mounier Kuhn Syndrome (MKS) is a rare congenital anomaly characterized by abnormal dilatation of the trachea and main bronchi. The aim of this study is to discuss tracheal volume measurement in MKS, and the pathologies accompanying MKS, especially pulmonary artery enlargement.

MATERIALS AND METHODS

38 patients, 18 of whom were diagnosed with MKS and 20 as control group, were included in the study. Trachea volume and pulmonary artery diameter were measured through thorax-computed tomography (CT) images of the patients. Accompanying pathologies were recorded.

RESULTS

In the measurements done through the CT scans, the trachea volume was found to be 25.45 cm3 in the control group and 44.17 cm3 in the patient group. The most frequent accompanying pathologies were tracheal diverticulum, bronchiectasis and pulmonary artery enlargement.

CONCLUSION

In patients with MKS, there is a significant difference in volume calculation as in trachea diameter. Though bronchiectasis and tracheal diverticulum are known as pathologies most frequently accompanying MKS, to the knowledge of the researchers, pulmonary artery enlargement due to the increase in pulmonary truncus diameter was first emphasized in this article.

[Three-dimensional reconstruction of cervical CT vs ultrasound for estimating residual thyroid volume]

OBJECTIVE

To compare the accuracy of three-dimensional reconstruction of cervical CT and ultrasound for estimating residual thyroid volume.

METHODS

We performed a retrospective analysis of 17 patients with 21 residual thyroid glands undergoing thyroidectomy surgery between February, 2017 and March, 2018 in our department. We compared the residual thyroid volume in preoperative ultrasound with the intraoperative measurement and the volume measured using threedimensional CT reconstruction before surgery.

RESULTS

The maximum vertical and anterioposterior diameters of the residual thyroid measured by preoperative ultrasound differed significantly from the volume data measured intraoperatively (P &lt; 0.05), but the difference in the maximum left-right diameters was not statistically significant (P&gt;0.05). The maximum vertical, leftright, and anteroposterior diameters estimated by three-dimensional reconstruction of cervical CT was all similar with those measured intraoperatively (P&gt;0.05).

CONCLUSIONS

Compared with ultrasound examination, three-dimensional reconstruction of neck CT is more accurate for estimating the residual thyroid volume and provides more reliable evidence for clinical calculation of postoperative I¹³¹ dose for thyroid cancer.

Thyroid Gland 18F-FDG Uptake in Neurofibromatosis Type 1

PURPOSE

To investigate thyroid gland characteristics on ¹⁸F-FDG positron emission tomography/computed tomography (PET/CT) imaging in patients with neurofibromatosis type 1 (NF1).

SUBJECTS AND METHODS

Thyroid gland characteristics of patients with a clinical diagnosis of NF1 who underwent ¹⁸F-FDG PET/CT imaging for the first time to distinguish benign neurofibroma from malignant peripheral nerve sheath tumor (MPNST) at our institution (n = 69) were compared to PET/CT imaging of sarcoidosis (n = 25) and early stage lung cancer (T₁N₀M₀ tumors, n = 15) patients.

RESULTS

Two NF1 patients (3%) showed a diffuse ¹⁸F-FDG uptake in the thyroid gland, 2 patients (3%) had an irregular uptake, and 7 patients (10%) had a focal uptake. Among the sarcoidosis patients, 1 showed a diffuse uptake (4%) and 1 had an irregular uptake (4%). In the early stage lung cancer group, 1 patient showed a diffuse uptake (7%) and 1 had a focal uptake (7%). NF1 patients had larger mean thyroid volume and mean SUV_max compared to sarcoidosis patients but not compared to early stage lung cancer patients. Four NF1 patients were diagnosed with multinodular goiter, 2 patients were diagnosed with benign chronic lymphocytic thyroiditis, 1 patient had metastasis to the thyroid, and 1 patient had medullary thyroid cancer.

CONCLUSION

Even though NF1 patients did not show an increased risk of thyroid incidentaloma on PET/CT compared to previous studies on non-thyroid cancer patients, the incidence shows that awareness of possible thyroid disease is important.

Multimodal evaluation of 2-D and 3-D ultrasound, computed tomography and magnetic resonance imaging in measurements of the thyroid volume using universally applicable cross-sectional imaging software: a phantom study

A precise estimate of thyroid volume is necessary for making adequate therapeutic decisions and planning, as well as for monitoring therapy response. The goal of this study was to compare the precision of different volumetry methods. Thyroid-shaped phantoms were subjected to volumetry via 2-D and 3-D ultrasonography (US), computed tomography (CT) and magnetic resonance imaging (MRI). The 3-D US scans were performed using sensor navigation and mechanical sweeping methods. Volumetry calculation ensued with the conventional ellipsoid model and the manual tracing method. The study confirmed the superiority of manual tracing with CT and MRI volumetry of the thyroid, but extended this knowledge also to the superiority of the 3-D US method, regardless of whether sensor navigation or mechanical sweeping is used. A novel aspect was successful use of the same universally applicable cross-imaging software for all modalities.

3D ultrasonography is as accurate as low-dose CT in thyroid volumetry

AIM

The purpose of this study was to compare thyroid volumetry by three-dimensional mechanically swept ultrasonography (3DmsUS) and low-dose computed tomography (ldCT).

PATIENTS, METHODS

30 subjects referred for radioiodine therapy of benign thyroid diseases were subjected to 3DmsUS and ldCT. A prerequisite of 3DmsUS analyses was that the scans had to capture the entire thyroid, excluding therefore cases with a very large volume or retrosternal portions. The 3DmsUS data were transformed into a DICOM format, and volumetry calculations were performed via a multimodal workstation equipped with standard software for cross-sectional imaging. Volume was calculated applying both the ellipsoid model and a manually tracing method. Statistical analyses included 95% confidence intervals (CI) of the means and limits of agreement according to Bland and Altman, the latter including 95% of all expected values.

RESULTS

Volumetric measurements by 3DmsUS and ldCT resulted in very high, significant correlation coefficients, r = 0.997 using the ellipsoid model and r = 0.993 with the manually tracing method. The mean relative differences of the two imaging modalities proved very small (-1.2±4.0% [95% CI -2.62; 0.28] using the ellipsoid model; -1.1±5.2% [95% CI -2.93; 0.80] using the manually tracing method) and the limits of agreement sufficiently narrow (-9.1% to 6.8%; -11.3% to 9.2%, respectively).

CONCLUSION

For moderately enlarged thyroids, volumetry with 3DmsUS proved comparable to that of ldCT, irrespective of whether the ellipsoid model or the manually tracing method was applied. Thus, 3DmsUS qualifies as a potential alternative to ldCT, provided that the organ is completely accessible. The use of a standard workstation for cross-sectional imaging with routine software did not prove problematic.

Sorafenib induced thyroiditis in two patients with hepatocellular carcinoma

BACKGROUND

Sorafenib is a multi-targeted tyrosine kinase inhibitor licensed for the treatment of hepatocellular carcinoma and renal cell carcinoma. Thyroid function test abnormalities have been reported for different tyrosine kinase inhibitors, but only limited data on thyroid function test abnormalities related to sorafenib are available, demonstrating the occurrence of hypothyroidism in patients treated with sorafenib.

SUMMARY

We describe two patients who developed temporary hyperthyroidism during the course of sorafenib treatment, which was followed by overt and subclinical hypothyroidism, respectively. Thyroid ultrasonography showed an atrophic thyroid gland in patient 1 , and signs of thyroiditis in patient 2 . Detailed reassessment of thyroid volumes on routinely performed computerized tomography scans showed a gradual decrease in thyroid volume during sorafenib treatment in one patient, suggesting progressive thyroid destruction.

CONCLUSION

This case report describes in detail and for the first time two cases of sorafenib-induced thyroiditis. We assume that this sorafenib-induced destructive thyroiditis is an important cause of sorafenib-induced hypothyroidism.