• Journal of radiological science and technology
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• v.46 no.5
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• pp.401-408
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• 2023

Thyroid uptake measurements can be subject to measurement errors due to the scoping and positioning of the thyroid gland. To compensate for these limitations, the clinical utility of the thyroid simultaneous counting method as an alternative to thyroid uptake measurement was analyzed and evaluated experimentally through quantitative analysis of images acquired after thyroid scanning. Experimental data were obtained using a Gamma camera (GE infinia), a thyroid uptake system (KOROID 1), and a thyroid neck phantom. Based on the thyroid uptake rate of 1-5% according to the protocol of thyroid scan test (^99mTcO₄ - , 370 MBq) in normal results, ^99mTcO₄ - was set in the range of 3.7-18.5 MBq (Matrix: 256×256, Scan time: 1 min, collimator: pin hole, phantom-collimator distances: 7 cm). The acquired images were corrected for the attenuation of isotopes due to the set-up time and half-life by applying the Auto Region of interest (ROI) drawing system, and the significance of the experimental results was evaluated by Multiple linear regression analysis (SPSS, ver. 22, IBM). The thyroid uptake rate showed a significant correlation between the dose and the measured counts when using the thyroid uptake system equipment. Meanwhile, the quantitative analysis counts of phantom images using Gamma camera also showed a significant correlation. Thus confirmed that the correlation between these two experiments was statistically significant (P<0.05). The simultaneous counting protocol, which indirectly measures thyroid uptake from thyroid scans, is likely to be clinically relevant if complemented by additional studies with different variables in patients with thyroid disease.

• The Korean journal of internal medicine
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• v.33 no.6
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• pp.1050-1057
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• 2018

Thyroglobulin antibody (TgAb) is a class G immunoglobulin and a conventional marker for thyroid autoimmunity. From a clinical perspective, TgAb is less useful than thyroid peroxidase antibodies for predicting thyroid dysfunction. However, TgAb is found more frequently in differentiated thyroid cancer (DTC) and can interfere with thyroglobulin (Tg) measurements, which are used to monitor the recurrence or persistence of DTC. Recent studies suggested a small but consistent role for preoperative TgAb in predicting DTC in thyroid nodules, and in reflecting adverse tumor characteristics or prognosis, including lymph node metastasis, but this is still controversial. Postoperative TgAb can serve as a biomarker for remnant thyroid tissue, so follow-up measures of TgAb are useful for predicting cancer recurrence in DTC patients. Since high serum TgAb levels may also affect the fine needle aspiration washout Tg levels from suspicious lymph nodes of DTC patients, it is important to use caution when interpreting the washout Tg levels in patients who are positive for TgAb.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.1118-1123
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• 2009

Ten hospitals from the Gwangju area were used to examine shallow dose to eyes and thyroid from panoramagraphy. Thermoluminescent dosimeter (TLD) and Photoluminescent dosimeter (PLD) were used as measurement devices at each hospital. ICRP 60 and ICRP 73 set standards for acceptability for eyes at 15mSv and thyroid at 1mSv per year. Left eye measures with TLD and PLD resulted in 0.19mSv and 0.24mSv respectively. Right eye measures with TLD and PLD resulted in 0.23mSv and 0.25mSv respectively. Thyroid measures with TLD and PLD resulted in 0.08mSv and 0.25mSv respectively with both measures not exceeding standards for acceptance. There was a significant difference in comparing the left eye and thyroid for TLD and PLD (p<0.01). There was no significant difference with the right eye (p>0.05). The absorbed dose measurements for eyes and thyroid using TLD and PLD in regards to panorama devices at each hospital were within the ICRP 60 recommendations; however, with the possibility of stochastic effect, all dose levels were taken into consideration.

• International journal of thyroidology
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• v.11 no.2
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• pp.109-116
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• 2018

It is very important to identify recurrent laryngeal nerve (RLN) and prevent RLN injury during thyroid surgery. The intraoperative neuromonitoring (IONM) for the prevention of RLN injury is a useful method because it can identify the location and status of RLN and predict postoperative vocal cord function easily. The IONM consists of a stimulating side that applies electrical stimulation to the nerve and a recording side that measures the surface electromyography (EMG) of the vocal cord muscle through electrode endotracheal tube. The nerve stimulator and surgical dissector are separate instruments. So, during IONM for the prevention of the RLN injury in conventional, endoscopic, or robotic thyroid surgery, repeated exchanging between surgical instruments and the nerve stimulator is inconvenient and time consuming. On the recording side, the accuracy of the electrode endotracheal tube which measures the EMG of the vocalis muscle can be affected by contact with between electrode and vocal fold and position change of patient. We would like to introduce recent several researches to overcome the current limitations of IONM.

• The Korean Journal of Nuclear Medicine
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• v.35 no.6
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• pp.393-397
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• 2001

Surgery, radioiodine therapy, and thyroxine treatment represent established therapeutic measures of proven efficacy for the treatment of well-differentiated thyroid cancer. However, in some cases, dedifferentiation is noted and it makes tumors refractory to conventional treatment. Recently, retinoic acid redifferentiation therapy was evaluated in several in vitro and in vivo studios. We report a patient with papillary carcinoma in whom metastatic lesions became radioiodine negative on high-dose therapy. Redifferentiation therapy with retinoic acid induced radioiodine uptake in some of metastatic tissues. Side effects such as xerostomia and cheilosis were mild. We recommend retinoic acid redifferentiation therapy as an option for the treatment of thyroid cancer with negative radioiodine uptake after high-dose radioiodine therapy.

• Journal of Environmental Health Sciences
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• v.44 no.6
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• pp.572-580
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• 2018

Objectives: Human biomonitoring (HBM) is a measurement of the chemicals and their metabolites in human biological samples and has been successfully employed to determine the exposure levels of environmental chemicals. In this study, we analyzed seasonal variations of the blood or urinary levels of chemicals, and assessed that these differences could affect the results of association study. Methods: The Korea National Environmental Health Survey (KoNEHS) is a nationwide survey that analyzes exposure levels of environmental pollutants, 19 kinds of chemicals including heavy metals and organic chemicals, and the exposure factors in the general population. Based on KoNEHS data, we analyzed the levels of chemicals concentrations over the total survey period (2012-2014) and each season, and assessed the association of thyroid measures with phthalate metabolite and BPA. Results: Exposure levels of blood mercury and lead were lower in summer compare to winter. Bisphenol A and PAHs metabolites were higher in spring and summer, but lower in autumn. VOCs metabolites were generally lower in summer and autumn. Phthalate metabolites were higher in all other seasons than in winter. Pyrethroid metabolite, 3-PBA, was higher in summer and autumn. Regarding seasonal variation of chemical exposures, the statistical significance and size of effects between thyroid measures and phthalate and BPA were changed with season. Conclusion: Seasonal variations of chemical exposure and health outcome should be considered for interpreting biomonitoring results from a public health context.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.13
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• pp.5187-5194
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• 2014

Background: Numerous studies have suggested that selenium deficiency may be associated with an increased risk for several types of cancer, but few have focused on thyroid cancer. Materials and Methods: We examined the association between post-diagnostic fingernail selenium levels and differentiated thyroid cancer risk in a French Polynesian matched case-control study. Conditional logistic regression models were used to estimate odds ratios and 95% confidence intervals. Results: The median selenium concentration among controls was $0.76{\mu}g/g$. Significantly, we found no association between fingernail selenium levels and thyroid cancer risk after conditioning on year of birth and sex and additionally adjusting for date of birth (highest versus lowest quartile: odds-ratio=1.12, 95% confidence interval: 0.66-1.90; p-trend=0.30). After additional adjustment for other covariates, this association remained non-significant (p-trend=0.60). When restricting the analysis to thyroid cancer of 10 mm or more, selenium in nails was non-significantly positively linked to thyroid cancer risk (p-trend=0.09). Although no significant interaction was evidenced between iodine in nails and selenium in nails effect (p=0.70), a non-significant (p-trend =0.10) positive association between selenium and thyroid cancer risk was seen in patients with less than 3 ppm of iodine in nails. The highest fingernail selenium concentration in French Polynesia was in the Marquises Islands ($M=0.87{\mu}g/g$) and in the Tuamotu-Gambier Archipelago ($M=0.86{\mu}g/g$). Conclusions: Our results do not support, among individuals with sufficient levels of selenium, that greater long-term exposure to selenium may reduce thyroid cancer risk. Because these findings are based on post-diagnostic measures, studies with prediagnostic selenium are needed for corroboration.

• Korean Journal of Psychosomatic Medicine
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• v.21 no.2
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• pp.132-139
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• 2013

Objectives: The aims of this study were to know the prevalence of cognitive disorders in patients with thyroid cancer, and identify related variables to them. Methods: Subjects were consisted of fourty-two patients with thyroid cancer, who were admitted for radioiodine ablative therapy at 6-12 months after total thyroidectomy. The data were obtained from interviews about history and assessments of depression and cognitive function(Korean Version of the Montreal Cognitive Assessment, MoCA-K). Results: 1) Among subjects, those with below 22 of total score of the MoCA-K were twenty-one(50.0%). 2) Upon age, education, Pre-radioiodine therapy thyroid stimulating hormone(TSH), there were statistically significant difference between subgroup with above 23 of the total MoCA-K score and those below 22. 3) The total scores of the MoCA-K in subjects had significant correlation with age, education, comorbidity, Pre-radioiodine therapy TSH, total score of the HDRS-17. Conclusions: Cognitive disorders were more prevalent among patients with thyroid cancer before radioiodine therapy. Therefore, further study should be needed to clarify the mechanism for the cognitive disorders in thyroid cancer. Furthermore, physicians should pay attention to the cognitive function and prepare preventative measures for cognitive disorder during management of thyroid cancer.

• The Korean Journal of Pain
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• v.33 no.1
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• pp.73-80
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• 2020

Background: The aim of this study was to evaluate radiation exposure to the eye and thyroid in pain physicians during the fluoroscopy-guided cervical epidural block (CEB). Methods: Two pain physicians (a fellow and a professor) who regularly performed C-arm fluoroscopy-guided CEBs were included. Seven dosimeters were used to measure radiation exposure, five of which were placed on the physician (forehead, inside and outside of the thyroid protector, and inside and outside of the lead apron) and two were used as controls. Patient age, sex, height, and weight were noted, as were radiation exposure time, absorbed radiation dose, and distance from the X-ray field center to the physician. Results: One hundred CEB procedures using C-arm fluoroscopy were performed on comparable patients. Only the distance from the X-ray field center to the physician was significantly different between the two physicians (fellow: 37.5 ± 2.1 cm, professor: 41.2 ± 3.6 cm, P = 0.03). The use of lead-based protection effectively decreased the absorbed radiation dose by up to 35%. Conclusions: Although there was no difference in radiation exposure between the professor and the fellow, there was a difference in the distance from the X-ray field during the CEBs. Further, radiation exposure can be minimized if proper protection (thyroid protector, leaded apron, and eyewear) is used, even if the distance between the X-ray beam and the pain physician is small. Damage from frequent, low-dose radiation exposure is not yet fully understood. Therefore, safety measures, including lead-based protection, should always be enforced.

• Korean Journal of Bronchoesophagology
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• v.2 no.1
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• pp.71-81
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• 1996

The normal larynx locates to the front of the neck symmetrically and the thyroid notch lies in the center of the neck, but practically the larynx is not symmetric in all people. From a clinical point of views, there are vague cases to decide whether a disordered laryngeal structure is within normal variations or a pathologic condition. The purpose of this study is to investigate the anatomy of the laryngeal framework in normal population. Authors investigate various measures of normal laryngeal framework, such as symmetry and length of the larynx, levels of the hyoid bone and vocal cord and angle of thyroid cartilage by using calipers and protractor on 45 cases of neck CT. The results are summerized as follows. 1. The laryngeal framework was asymmetric to a greater or lesser extent in most cases with directional preponderance to the right side. The degree of asymmetry did not differ among different age groups and between seres. 2. The level of the hyoid bone ranged from C2-C3 vertebrae to C5-C6 intervertebral space with most frequent level of C5. 3. The level of the vocal cord ranged from 01 vertebra to C6-C7 intervertebral space with most frequent level of C5. 4. The angle of thyroid cartilage ranged from 58 degree to 100 degree with average of 81.5 and mean angle between both thyroid alae were 77.24 degree in male and 87.88 degree in female.