• Journal of radiological science and technology
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• v.30 no.3
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• pp.237-243
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• 2007

Phantoms are very necessary for quality assurance of radio nuclides imaging systems to maintain standards and to ensure reproducibility of test. General quality assurance and instrument quality control are essential in every hospital. The human tissue equivalent materials are aluminum, areryl, water and epoxy..etc. It is very important to select optimum equivalant materials for a phantoms in QC. Especially, paraffin is very similar with human soft tissue in X or Gamma-ray physical characteristics and easy to buy with economically. We made a paraffin thyroid phantom and compare with thyroid areryl phantom, also used commercially in practice. Two small size cold spots(3 and 6 mm diameter) and a hot spot(3 mm diameter) embeded in paraffin phantom. And imaged with $^{99m}TcO_4$ by camera for analysis about spatial resolution and noise at the hot and cold spots. We got some results as below : 1. No difference in counting rate and noise between both arcryl and paraffin thyroid phantoms. 2. The best spatial resolution can be seen 6 cm distance between pinhole collimator and thyroid phantoms(arcryl and paraffin). 3. More optimal spatial resolution could acquired in paraffin thyroid phantom. Paraffin is very similar with human soft tissue in atomic number, density and relative absorbtion function, and can be shaped easily what we wanted. So we can recommendation paraffin as quality assurance phantom because its usefulness, economical benefit and purchasability.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.707-711
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• 2013

Purpose: To investigate the clinical features and prognosis of papillary thyroid carcinoma (PTC) with a background of benign disease. Method: A total of 709 patients with papillary thyroid carcinoma undergoing surgical resection were analyzed retrospectively. In 147 patients who underwent surgery for benign thyroid disease, incidental PTC (IPC group) were identified by intraoperative or postoperative pathological examination of surgical specimens but were not detected by preoperative imaging studies. In the other group, according to the pathological examination with or without co-existing benign thyroid disease, 253 cases were clarified as concomitant PTC and 309 cases were clarified as dominant PTC. Results: Incidental PTC was more common in women, about 85.7%, the mean age was $47.6{\pm}11.3$ years old. Average tumor diameter was $4.4{\pm}2.2$ mm, multiple lesions accounted for 12.9% (19/147), and the cervical lymph node metastasis rate was 6.1% (9/147). After radical resection 8 cases recurred, the median time of recurrence was about 12 months (0.5 to 162), there was no tumor-related death. The tumor-free survival rates were 97.3%, 95.9%, 91.5%, and 79.3% in 1, 5, 10 and 14 year respectively. Conclusion: Incidental PTC with a background of benign lesions is common, and the generally good prognosis can be attributed to tumor early detection and early treatment. On the intraoperative finding of incidental PTC, lobectomy (unilateral) or total thyroidectomy (bilateral) should be the first choice, but with a postoperative pathologic finding of incidental PTC, further treatment, such as completion thyroidectomy or immediate lymph dissection is not necessary. Central lymph node dissection is also not needed unless lymphadenectasis is present.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.1
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• pp.51-52
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• 2006

A 39-year-old female patient who had undergone a total thyroidectomy for a papillary thyroid carcinoma underwent a whole body scan with I-131. The I-131 scan was performed 72 hours after administering 185 MBq (5 mCi) of an I-131 solution. The anterior image of the head, neck, and upper chest showed multiple areas of increased uptake in the mediastinal area considering of functional metastasis. However, radioactivity was not evident in the image taken after removing her clothes and muffler. The image obtained after placing the muffler on the pallet showed that the radioactivity was still present. It is well known that artifacts on an I-131 scan can be produced by styling hair sputum, drooling during sleep, chewing gum, and paper or a cloth handkerchief that is contaminated with the radioactive iodine from either perspiration or saliva. This activity might be mistaken for a functional metastasis. Therefore, it is essential that an image be obtained after removing the patient's clothes. In this study, artifacts due to a contaminated muffler on the I-131 scan were found. These mimicked a functional metastasis of the mediastinal area in a patient with a papillary thyroid carcinoma.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.29 no.1
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• pp.24-29
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• 2018

Background and Objectives : The purpose of this study was to evaluate the impact of surgical extent on voice using acoustic and aerodynamic measurements in a serially followed thyroidectomy patients. Materials and Method : From October 2015 to January 2017, 108 patients who had undergone thyroid surgery and voice test for preoperative, 2, 3, and 6 months postoperatively were classified into five operative types. The radiological stage preoperatively and histopathological stage postoperatively were classified according to the invasion of thyroid capsule and surrounding tissue. For each classification, the results of the voice analysis according to the period were compared and analyzed. Results : The difference of voice according to surgical extent, radiological stage, and histopathologic stage showed significant difference only with Maximal phonation time (MPT) over time. However, in the analysis of interaction between each classification and period, Phonation threshold pressure (PTP) only showed significant results. Conclusion : Differences in imaging and histopathologic stages have no significant effect on recovery of voice symptoms after thyroid surgery. As the extent of operation increases, the pressure to start vocalization is relatively higher, which also varies with time after surgery.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.1
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• pp.90-93
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• 2011

Purpose: A Pixelated BSGI gamma camera has features to enhance resolution and sensitivity and minimize the distance between detector and organs by narrow FOV. Therefore, it is known as useful device to examine small organs such as thyroid, parathyroid and gall bladder. In general, when we would like to enlarge the size of images and obtain high resolution images by gamma camera in nuclear medicine study, we use pinhole collimator. The purpose of this study is to evaluate the usefulness of Pixelated BSGI gamma camera and to compare to it using pinhole collimator in thyroid scan which is a study of typical small organs. Materials and methods: (1) The evaluation of sensitivity and spatial resolution: We measured sensitivity and spatial resolution of Pixelated BSGI with LEHR collimator and Infinia gamma camera with pinhole collimator. The sensitivity was measured by point source sensitivity test recommended by IAEA. We acquired images considering dead time in BSGI gamma camera for 100 seconds and used $^{99m}TcO4-\;400{\mu}Ci$ line source. (2) The evaluation of thyroid phantom: The thyroid phantom was filled with $^{99m}TcO4-$. After set 300 sec or 100 kcts stop conditions, we acquired images from both pixelated BSGI gamma camera and Infinia gamma camera with LEHR collimator. And we performed all thyroid studies in the same way as current AMC's procedure. Results: (1) the result of sensitivity: As a result, the sensitivity and spatial resolution of pixelated BSGI gamma camera were better than Infinia's. The sensitivities of pixelated BSGI and Infinia gamma camera were $290cps/{\mu}Ci$ and $350cps/{\mu}Ci$ respectively. So, the sensitivity of pixelated BSGI was 1.2 times higher than Infinia's (2) the result of thyroid phantom: Consequently, we confirmed that images of Pixelated BSGI gamma camera were more distinguishable between hot and cold spot compared with Infinia gamma camera. Conclusion: A pixelated BSGI gamma camera is able to shorten the acquisition time. Furthermore, the patients are exposed to radiation less than before by reducing amount of radiopharmaceutical doses. Shortening scan time makes images better by minimizing patient's breath and motion. And also, the distance between organ and detector is minimized because detector of pixelated BSGI gamma camera is small and possible to rotate. When patient cannot move at all, it is useful since device is feasible to move itself. However, although a pixelated BSGI gamma camera has these advantages, the effect of dead time occurs over 2000 cts/s since it was produced only for breast scan. So, there were low concentrations in organ. Therefore, we should consider that it needs to take tests to adjust acquisition time and amount of radiopharmaceutical doses in thyroid scan case with a pixelated BSGI gamma camera.

• Journal of radiological science and technology
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• v.40 no.2
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• pp.237-243
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• 2017

This study evaluated the applicability of computer-aided diagnosis by retrospective analysis of GLCM algorithm based on cytopathological diagnosis of normal and malignant nodules in thyroid ultrasound images. In the experiment, the recognition rate and ROC curve of thyroid malignant nodule were analyzed using 6 parameters of GLCM algorithm. Experimental results showed 97% energy, 93% contrast, 92% correlation, 92% homogeneity, 100% entropy and 100% variance. Statistical analysis showed that the area under the curve of each parameter was more than 0.947 (p = 0.001) in the ROC curve, which was significant in the recognition of thyroid malignant nodules. In the GLCM, the cut-off value of each parameter can be used to predict the disease through analysis of quantitative computer-aided diagnosis.

• Korean Journal of Radiology
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• v.21 no.5
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• pp.598-604
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• 2020

Objective: Proper management of lymph nodes (LNs) with ultrasonographic (US) indeterminate features in thyroid cancer patients remains elusive. We aimed to evaluate the malignancy risk and US findings predictive of malignancy for US indeterminate LNs in preoperative thyroid cancer patients through node-by-node correlation. Materials and Methods: A total of 348 LNs in 284 thyroid cancer patients, who underwent fine-needle aspiration or core-needle biopsy between December 2006 and June 2015, were included. We determined the malignancy risks for US probably benign, indeterminate, and suspicious categories. For US indeterminate LNs, which had neither echogenic hilum nor hilar vascularity in the absence of any suspicious finding, US findings were compared between benign and metastatic LNs using Mann-Whitney U test and Fisher's exact test. Results: US imaging diagnoses were probably benign in 20.7% (n = 72) cases, indeterminate in 23.6% (n = 82), and suspicious in 55.7% (n = 194). Malignancy risk of US indeterminate LNs (19.5% [16/82]) differed from those of the US probably benign (2.8% [2/72]) (p = 0.002) and US suspicious LNs (78.4% [152/194]) (p < 0.001). Among US indeterminate LNs, there were no significant differences in short, long, and long-to-short diameter (L/S) ratios between benign and metastatic LNs (3.9 vs. 3.8 mm, p = 0.619; 7.3 vs. 7.3 mm, p = 0.590; 1.9 vs. 1.9, p = 0.652). Conclusion: US indeterminate LNs were frequently encountered during preoperative evaluation and had intermediate malignancy risk. Given the lack of discriminative power of size criteria and L/S ratio, clinical factors such as surgical strategy and node size should be considered for proper triage of US indeterminate LNs in thyroid cancer.

• Korean Journal of Veterinary Research
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• v.64 no.2
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• pp.10.1-10.9
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• 2024

Hyperthyroidism, characterized by elevated thyroid hormone levels and thyroid gland hyperplasia or adenoma, is a prevalent endocrinopathy in older cats. Treatment options include antithyroid drugs, surgical thyroidectomy, and radioiodine therapy (RAIT), which is non-invasive treatment option that can achieve complete remission. However, efficacy and safety of RAIT in hyperthyroid cats have not been investigated in South Korea. This study includes 10 hyperthyroid cats with RAIT. Initial assessments comprised history, physical examination, blood analysis, and serum total T4 (tT4) concentration. Thyroid scintigraphy revealed hyperactivity and enlargement of thyroid gland at 24 hours before the RAIT. Radioiodine (RAI) was injected subcutaneously with 2 to 6 mCi, determined by the fixed dose or the scoring system based on severity of clinical signs, tT4 concentration, and thyroid size individually. After RAIT, the concentration of serum tT4 and liver enzymes were significantly decreased at discharge. However, no significant differences were noted in blood urea nitrogen, creatinine, symmetric dimethylarginine, hematocrits, and white blood cell counts pre- and post-treatment. Although 4 cats received RAI twice, clinical signs disappeared and tT4 levels decreased following the RAIT. All 10 cats achieved complete remission after 6 months without critical adverse effect. The safety and the effectiveness of RAIT was confirmed based on protocols reported other countries. Therefore, RAIT could be considered the treatment option and prevent adverse effects from medication or surgery. This preliminary study presents the first evaluation of RAIT for hyperthyroid cats using locally produced RAI in South Korea and provide valuable insight for clinicians and further studies.

• Korean Journal of Head & Neck Oncology
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• v.16 no.1
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• pp.64-68
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• 2000

Objectives: With the recent advances and increasing use of imaging techniques in examination of the neck, the incidence of incidentally discovered thyroid carcinoma has been increasing. This study was carried out to evaluate the clinicopathologic characteristics of incidental thyroid carcinomas and to find optimal therapeutic strategies for these lesions. Materials & Methods: From Jan. 1988 to Aug. 1998, 1,053 patients were operated on for thyroid cancer, of whom 127(12.1%) had incidentally discovered thyroid cancers which were identified during routine health checkups(n=40), diagnostic procedures for unrelated medical conditions(n=39) and mass screening for thyroid cancer(n=48). The preoperative diagnosis was obtained by ultrasound-guided FNAB and the extent of surgery was determined based on frozen section examinations, as well as prognostic factors and gross findings at the time of surgery. Results: There were 6 men and 121 women with a mean age of 45.9 years. Histopathological diagnosis included papillary carcinomas(n=1l9), follicular carcinomas(n=6), poorly differentiated carcinoma(n=l) and medullary carcinoma(n=1). Thirty patients(23.6%) had multifocallesions. The mean diameter of the tumors was 1.1 cm(0.2-3.4 cm). Capsular invasions were found in 53 patients(41.7%) and nodal metastases in 41(32.3%). The surgical procedures used were: 90 less-than total thyroidectomies and 37 total thyroidectomies with central neck node dissection. Lateral neck dissection was added in 5 patients. According to TNM staging, 79 patients(63.2%) were at stage I, 15(12.0%) at stage II, 31(24.8%) at stage III and 0(0.0%) at stage IV. By AMES scoring system, 102 patients(81.6%) were in the low-risk group and 23(18.4%) in the high-risk group. And by MACIS scoring system, 103(86.6%) of 119 papillary thyroid cancer patients were less than 6. Conclusions: The clinicopathological characteristics of incidentally discovered thyroid carcinomas are similar to ordinary thyroid carcinomas. The treatment of choice should be individualized based on the particular clinical situation encountered, as in ordinary thyroid carcinomas.

• Journal of the Korean Society of Radiology
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• v.15 no.4
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• pp.473-479
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• 2021

The diagnostic criteria for diffuse thyroid disease are ambiguous and there are many errors due to the subjective diagnosis of experts. Also, studies on ultrasound imaging of thyroid nodules have been actively conducted, but studies on diffuse thyroid disease are insufficient. In this study, features were extracted by applying the GLCM algorithm to ultrasound images of normal and diffuse thyroid disease, and quantitative analysis was performed using the extracted feature values. Using the GLCM algorithm for thyroid ultrasound images of patients diagnosed at W hospital, 199 normal cases, 132 mild cases, and 99 moderate cases, a region of interest (50×50 pixel) was set for a total of 430 images, and Autocorrelation, Sum of squares, sum average, sum variance, cluster prominence, and energy were analyzed using six parameters. As a result, in autocorrelation, sum of squares, sum average, and sum variance four parameters, Normal, Mild, and Moderate were distinguished with a high recognition rate of over 90%. This study is valuable as a criterion for classifying the severity of diffuse thyroid disease in ultrasound images using the GLCM algorithm. By applying these parameters, it is expected that errors due to visual reading can be reduced in the diagnosis of thyroid disease and can be utilized as a secondary means of diagnosing diffuse thyroid disease.