Relationship between the sonographic appearance of the thyroid and the clinical course and autoimmune activity of Graves' disease

Association of autoimmune thyroid disease with type 1 diabetes mellitus and its ultrasonic diagnosis and management

As a common hyperglycemic disease, type 1 diabetes mellitus (T1DM) is a complicated disorder that requires a lifelong insulin supply due to the immune-mediated destruction of pancreatic β cells. Although it is an organ-specific autoimmune disorder, T1DM is often associated with multiple other autoimmune disorders. The most prevalent concomitant autoimmune disorder occurring in T1DM is autoimmune thyroid disease (AITD), which mainly exhibits two extremes of phenotypes: hyperthyroidism [Graves' disease (GD)] and hypo-thyroidism [Hashimoto's thyroiditis, (HT)]. However, the presence of comorbid AITD may negatively affect metabolic management in T1DM patients and thereby may increase the risk for potential diabetes-related complications. Thus, routine screening of thyroid function has been recommended when T1DM is diagnosed. Here, first, we summarize current knowledge regarding the etiology and pathogenesis mechanisms of both diseases. Subsequently, an updated review of the association between T1DM and AITD is offered. Finally, we provide a relatively detailed review focusing on the application of thyroid ultrasonography in diagnosing and managing HT and GD, suggesting its critical role in the timely and accurate diagnosis of AITD in T1DM.

The Sonographic Features of the Thyroid Gland After Treatment with Radioiodine Therapy in Patients with Graves' Disease

The aim of the study was to describe the typical sonographic features of the thyroid gland in patients with Graves' hyperthyroidism after radioiodine therapy (RIT). Thirty patients (21 female and 9 male) with a mean age of 53 y (standard deviation [SD] ± 11.3) and with previous Graves' disease who had been successfully treated with RIT were enrolled in the study. All were hypothyroid or euthyroid after treatment. The thyroid ultrasound was carried out by a single experienced operator with an 8-MHz linear transducer. Volume, vascularity, echogenicity and echotexture of the glands were noted. The presence of nodules and lymph nodes was also documented. The mean volumes of the right lobe were 2.4 mL ± 2.9 SD (0.6-14) and the left lobe were 1.8 mL ± 1.9 SD (0.4-9.1), with a mean total volume of 4.2 mL ± 4.7 SD (1.3-19.1). Of those who had a pre-treatment ultrasound (23%), the percentage reduction in volume was 87% (p < 0.05); 93% of the glands were hypovascular, with the remaining 7% showing normal vascularity. The glands were hyperechoic and of coarse echotexture. Overall, the sonographic features of the post-RIT gland included a significantly reduced mean total volume of 4.2 mL, hypovascularity, coarse echotexture and hyperechogenicity.

Quantitative assessment of the impact of biomedical image acquisition on the results obtained from image analysis and processing

Introduction

Dedicated, automatic algorithms for image analysis and processing are becoming more and more common in medical diagnosis. When creating dedicated algorithms, many factors must be taken into consideration. They are associated with selecting the appropriate algorithm parameters and taking into account the impact of data acquisition on the results obtained. An important feature of algorithms is the possibility of their use in other medical units by other operators. This problem, namely operator’s (acquisition) impact on the results obtained from image analysis and processing, has been shown on a few examples.

Material and method

The analysed images were obtained from a variety of medical devices such as thermal imaging, tomography devices and those working in visible light. The objects of imaging were cellular elements, the anterior segment and fundus of the eye, postural defects and others. In total, almost 200'000 images coming from 8 different medical units were analysed. All image analysis algorithms were implemented in C and Matlab.

Results

For various algorithms and methods of medical imaging, the impact of image acquisition on the results obtained is different. There are different levels of algorithm sensitivity to changes in the parameters, for example: (1) for microscope settings and the brightness assessment of cellular elements there is a difference of 8%; (2) for the thyroid ultrasound images there is a difference in marking the thyroid lobe area which results in a brightness assessment difference of 2%. The method of image acquisition in image analysis and processing also affects: (3) the accuracy of determining the temperature in the characteristic areas on the patient’s back for the thermal method - error of 31%; (4) the accuracy of finding characteristic points in photogrammetric images when evaluating postural defects – error of 11%; (5) the accuracy of performing ablative and non-ablative treatments in cosmetology - error of 18% for the nose, 10% for the cheeks, and 7% for the forehead. Similarly, when: (7) measuring the anterior eye chamber – there is an error of 20%; (8) measuring the tooth enamel thickness - error of 15%; (9) evaluating the mechanical properties of the cornea during pressure measurement - error of 47%.

Conclusions

The paper presents vital, selected issues occurring when assessing the accuracy of designed automatic algorithms for image analysis and processing in bioengineering. The impact of acquisition of images on the problems arising in their analysis has been shown on selected examples. It has also been indicated to which elements of image analysis and processing special attention should be paid in their design.

Value of the left inferior thyroid artery peak systolic velocity in diagnosing autoimmune thyroid disease

OBJECTIVES

The purpose of this study was to calculate a number of thyroid grayscale and Doppler sonographic parameters in healthy individuals and patients with Hashimoto thyroiditis or Graves disease and assess their sensitivity and specificity for the diagnosis of autoimmune thyroid disease using receiver operating characteristic curves.

METHODS

A consecutive series of 153 patients (70 euthyroid and 54 hypothyroid patients with Hashimoto thyroiditis and 29 patients with Graves disease), all selected from an outpatient endocrine clinic, and 48 age- and sex-matched healthy control participants were evaluated with grayscale and power Doppler sonography.

RESULTS

An irregular echo pattern in the thyroid parenchyma had 92.8% sensitivity for the diagnosis of autoimmune thyroid disease, and a left inferior thyroid artery peak systolic velocity (PSV) greater than 26.11 cm/s had 91.7% specificity. Of 8 patients with Hashimoto thyroiditis and normal grayscale sonographic characteristics, 6 had a left inferior thyroid artery PSV greater than 26.11 cm/s. A left inferior thyroid artery PSV greater than 61.65 cm/s had 82.8% sensitivity and 86.9% specificity for differentiating Hashimoto thyroiditis from Graves disease.

CONCLUSIONS

The left inferior thyroid artery PSV was the most accurate sonographic parameter for the diagnosis of autoimmune thyroid disease. Measurement of the inferior thyroid artery PSV could be used in patients with a normal grayscale sonographic appearance and inconclusive clinical and biochemical parameters to substantiate the diagnosis of autoimmune thyroid disease. Further studies are needed to evaluate and expand the use of this index.

Influence of the measurement method of features in ultrasound images of the thyroid in the diagnosis of Hashimoto's disease

INTRODUCTION

This paper shows the influence of a measurement method of features in the diagnosis of Hashimoto's disease. Sensitivity of the algorithm to changes in the parameters of the ROI, namely shift, resizing and rotation, has been presented. The obtained results were also compared to the methods known from the literature in which decision trees or average gray level thresholding are used.

MATERIAL

In the study, 288 images obtained from patients with Hashimoto's disease and 236 images from healthy subjects have been analyzed. For each person, an ultrasound examination of the left and right thyroid lobe in transverse and longitudinal sections has been performed.

METHOD

With the use of the developed algorithm, a discriminant analysis has been conducted for the following five options: linear, diaglinear, quadratic, diagquadratic and mahalanobis. The left and right thyroid lobes have been analyzed both together and separately in transverse and longitudinal sections. In addition, the algorithm enabled to analyze specificity and sensitivity as well as the impact of sensitivity of ROI shift, repositioning and rotation on the measured features.

RESULTS AND SUMMARY

The analysis has shown that the highest accuracy was obtained for the longitudinal section (LD) with the method of linear, yielding sensitivity = 76%, specificity = 95% and accuracy ACC = 84%. The conducted sensitivity assessment confirms that changes in the position and size of the ROI have little effect on sensitivity and specificity. The analysis of all cases, that is, images of the left and right thyroid lobes in transverse and longitudinal sections, has shown specificity ranging from 60% to 95% and sensitivity from 62% to 89%. Additionally, it was shown that the value of ACC for the method using decision trees as a classifier is equal to 84% for the analyzed data. Thresholding of average brightness of the ROI gave ACC equal to 76%.

Assessment of significance of features acquired from thyroid ultrasonograms in Hashimoto's disease

INTRODUCTION

This paper concerns the analysis of the features obtained from thyroid ultrasound images in left and right transverse and longitudinal sections. In the image analysis, the thyroid lobe is treated as a texture for healthy subjects and patients with Hashimoto's disease. The applied methods of analysis and image processing were profiled to obtain 10 features of the image. Then, their significance in the classification was shown.

MATERIAL

In this study, the examined group consisted of 29 healthy subjects aged 18 to 60 and 65 patients with Hashimoto's disease. For each subject, four ultrasound images were taken. They were all in transverse and longitudinal sections of the right and left lobe of the thyroid, which gave 376 images in total.

METHOD

10 different features obtained from each ultrasound image were suggested. The analyzed thyroid lobe was marked automatically or manually with a rectangular element.

RESULTS

The analysis of 10 features and the creation for each one of them their own decision tree configuration resulted in distinguishing 3 most significant features. The results of the quality of classification show accuracy above 94% for a non-trimmed decision tree.

Benign conditions of the thyroid gland

Infectious and autoimmune diseases account for the majority of benign conditions of the thyroid gland. They are usually diagnosed and followed by clinical examination and laboratory analyses, but when imaged, ultrasonography and computed tomography are the modalities of choice. In particular, fine needle aspiration under ultrasound guidance may be invaluable for diagnostic and therapeutic purposes.

Diffusion-weighed MR of the thyroid gland in Graves' disease: assessment of disease activity and prediction of outcome

RATIONALE AND OBJECTIVES

To assess the activity and clinical course of Graves' disease with diffusion-weighted magnetic resonance (MR) imaging.

MATERIALS AND METHODS

Fifty-one patients with Graves' disease and 25 volunteers underwent diffusion MR imaging of the thyroid gland using a single shot echo-planar imaging with b-factor of 0, 300 and 600 second/mm(2). The apparent diffusion coefficient (ADC) values of the thyroid gland were calculated. Patients with active Graves' disease included untreated patients at initial diagnosis (n = 12), patients under antithyroid drugs (n = 11), and patients in relapse after withdrawal of therapy (n = 13). Patients with inactive disease had a remission of hyperthyroidism (n = 15).

RESULTS

The mean ADC values of thyroid gland with active Graves' disease was 0.65 +/- 0.03 x 10(-3) mm(2)/second in patients at initial diagnosis, 0.81 +/- 0.02 x 10(-3) mm(2)/second in patients undergoing antithyroid drug and 0.72 +/- 0.07 x 10(-3) mm(2)/second in patients with relapse of hyperthyroidism. The mean ADC of patients with remission was 0.94 +/- 0.03 x 10(-3) mm(2)/second and for normal volunteer was 1.06 +/- 0.08 x 10(-3) mm(2)/second. There was significant difference in the ADC value of patients with active disease and remission (P = .001). The cutoff ADC value used for differentiating patients with active disease from patients with remission was 0.82 x 10(-3) mm(2)/second. The mean ADC value of thyroid gland had positive correlation with thyroid-stimulating hormone (r = 0.87, P = .001) and negative correlation with serum T4 (r = -0.82, P = .001) and serum T3 (r = -0.71, P = .001).

CONCLUSIONS

The ADC value of the thyroid gland is a promising non invasive parameter for diagnosis of different clinical stages of Graves' disease. Hence it can be used to assess the activity and predict the outcome of patients during and after medical treatment.

Development and evaluation of a PDA-based teleradiology terminal in thyroid nodule diagnosis

We developed a wireless personal digital assistant (PDA)-based teleradiology terminal which allowed a secure connection to the hospital's Picture Archiving and Communication System (PACS) through the DICOM protocol. Ten members of the hospital's medical staff completed a questionnaire about its mobility, usability, stability, performance and diagnostic efficiency in a real health-care environment. There was a high degree of satisfaction with the system's mobility (mean score 4.1, SD 1.0, on a five-point scale), usability (mean score 4.2, SD 1.1), stability (mean score 3.9, SD 0.4) and performance (mean score 4.2, SD 0.6). The system was evaluated as a tool for providing assistance in diagnosing thyroid nodules from ultrasound images. A total of 144 ultrasound images with thyroid nodules were assessed by an expert. Six image quality attributes were evaluated. The physician concluded that the ultrasound thyroid images on the PDA screen were of similar quality to those displayed on a diagnostic visual display unit screen. However, the expert found difficulties in diagnosing microcalcification, internal echo texture and vascularity. The PDA terminal provided rapid, secure and convenient portable access to PACS images and the image quality was sufficient for diagnostic interpretation of ultrasound images of the thyroid.

Ultrasonographic features of papillary thyroid carcinoma in patients with Graves' disease

BACKGROUND/AIMS

To characterize ultrasonographic findings in papillary thyroid carcinoma (PTC) combined with Graves' disease.

METHODS

Medical records and ultrasonographic findings of 1,013 patients with Graves' disease and 3,380 patients without Graves' disease were analyzed retrospectively. A diagnosis of PTC was based on a pathologic examination.

RESULTS

The frequency of hypoechogenicity was lower in patients with PTC and Graves' disease than in patients with PTC alone (p < 0.05). The frequency of perinodular blood flow in patients with PTC and Graves' disease was significantly higher than in those with PTC alone (p < 0.05). PTC combined with Graves' disease was characterized by more ill-defined borders and less frequency of overall calcification, punctate calcification, and heterogeneous echogenicity, although the difference was not statistically significant.

CONCLUSIONS

Our results suggest that patients with Graves' disease more frequently have atypical PTC findings on ultrasonography.

The reproducibility of the virtual organ computer-aided analysis program for evaluating 3-dimensional power Doppler ultrasonography of diffuse thyroid disorders

AIM

The aim of this study was to evaluate the intra- observer and inter-observer reproducibility of 3-dimensional (3D) power Doppler ultrasonography with the virtual organ computer-aided analysis (VOCAL) program for measuring thyroid volume and vascular indices in patients with diffuse thyroid disorders.

MATERIALS AND METHODS

Patients with diffuse goiters were examined by 3D ultrasonography from August 2005 to July 2006. The parameters for vascular assessment included the vascularization index (VI), flow index (FI), vascularization-flow index (VFI), and thyroid size, and were obtained using the VOCAL program. This program used plane A and a 30 degrees rotational step. Intra-observer and inter-observer repeatability are presented as intra-class correlation coefficient (intra-CC) and inter-class correlation coefficient (inter-CC), with values >0.70 being acceptable.

RESULTS

Sixty-three patients in total were enrolled for this study, including 19 patients with simple goiter and 44 patients with autoimmune thyroid disease (AITD) (23 Graves' disease, 21 Hashimoto's thyroiditis). Thyroid volume and 3 vascular indices showed excellent reproducibility in the AITD group (intra- CC>0.9373 and inter-CC>0.8763) and its subgroups. The VI had excellent consistent reproducibility in the simple goiter group (intra-CC>0.8987 and inter-CC>0.8881), but the other parameters did not.

CONCLUSIONS

Based on this study, 3D power Doppler ultrasonography with the VOCAL program is a reliable tool for evaluating diffuse thyroid disorders due to an autoimmune process. The VI is the most reliable parameter.

The role of imaging in Graves’ disease: A cost-effectiveness analysis

According to many guidelines, scintigraphy remains the first suggested diagnostic procedure in hyperthyroid patients in spite of the widespread availability of ultrasounds. The aim of this study was to evaluate the cost-effectiveness of sonography versus scintigraphy in the management of Graves's disease, and to assess ultrasound features suggesting cancer in detecting thyroid nodules. Among 1470 hyperthyroid patients evaluated in our department from 2002 to 2005, 426 (29%) had Graves' disease: echographic and scintigraphic features were not suggestive of GD in 20/426 (4.8%) and 11/426 (2.6%) patients, respectively (p=0.763), even if one of the two procedures was almost always diagnostic. Ultrasound identified 68/426 (16%) patients with a concomitant solid lesion, while scintigraphy detected only 9/426 (2.1%) "cold" nodules (p<0.001). Thyroid cancer was diagnosed in 30/68 (47.7%) patients. Malignancy presented at ultrasound investigation blurred margins (26.7% versus 15.8%), microcalcifications (33.3% versus 28.9%) and an anteroposterior and transverse diameter ratio>or=1 (73.3% versus 71.1%); more frequently than benign nodules, but this was not statistically significant. The total cost to obtain a diagnosis by ultrasound was euro14645.34 (euro13312.5 for echography+euro1332.84 for scintigraphy in the 29 patients "negative" at echographic evaluation for GD) versus euro19922.71 by scintigraphy (euro19578.96 for scan+euro343.75 for ultrasounds in the 11 patients "negative" at scintigraphy). Our data show no difference in terms of diagnosis between sonography and scintigraphy. Indeed, scintigraphy was less sensitive in detecting nodules (often of malignant nature) than ultrasound, and, moreover, with a consequent increase of the direct cost of nodule management when scintigraphy is the first line procedure. In conclusion, according to our results, we suggest that ultrasounds with color-Doppler evaluation should be performed as first step in all hyperthyroid patients, and that scintigraphic examination should be limited only to the uncommon cases, where physician's observation, laboratory assays and/or ultrasounds are not diagnostic.