• Korean Journal of Radiology
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• 제23권10호
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• pp.1019-1027
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• 2022

Objective: Thyroidectomy bed lesions frequently show suspicious ultrasound (US) features after thyroid surgery. Fine-needle aspiration (FNA) may not provide definitive pathological information about the lesions. Although core-needle biopsy (CNB) has excellent diagnostic performance in characterizing suspicious thyroid nodules, no published studies have evaluated the performance of CNB specifically for thyroidectomy bed lesions. Therefore, we aimed to evaluate the diagnostic performance and safety of CNB for characterizing thyroidectomy bed lesions. Materials and Methods: A total of 124 thyroidectomy bed lesions in 113 patients (79 female and 34 male; age, 23-85 years) who underwent US-guided CNB between December 2008 and December 2020 were included. We reviewed the US imaging features of the target lesions and the histories of previous biopsies. The pathologic results, diagnostic performance for malignancy, and complications of CNB were analyzed. Results: All samples (100%) obtained by CNB were adequate for pathological analysis. Pathological analysis revealed inconclusive results in two lesions (1.6%). According to the reference standard, 50 lesions were ultimately malignant (40.3%), and 72 were benign (58.1%), excluding the two inconclusive lesions. The performance of CNB for diagnosing malignant thyroidectomy bed lesions in the 122 lesions had a sensitivity of 98.0% (49/50), a specificity of 100% (72/72), positive predictive value of 100% (49/49), and negative predictive value of 98.6% (72/73). Eleven lesions were referred for CNB after prior inconclusive FNA results in thyroidectomy bed lesions, for all of which CNB yielded correct conclusive pathologic diagnoses. According to the pathological analysis of CNB, there were various benign lesions (58.9%, 73/124) besides recurrence, including benign postoperative lesions other than suture granuloma (32.3%, 40/124), suture granuloma (15.3%, 19/124), remnant thyroid tissue (5.6%, 7/124), parathyroid lesions (4%, 5/124), and abscesses (1.6%, 2/124). No major or minor complications were associated with the CNB procedure. Conclusion: US-guided CNB is accurate and safe for characterizing thyroidectomy bed lesions.

• Korean Journal of Radiology
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• 제24권10호
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• pp.1028-1037
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• 2023

Objective: To evaluate the computed tomography (CT) features for diagnosing metastatic cervical lymph nodes (LNs) in patients with differentiated thyroid cancer (DTC) and validate the CT-based risk stratification system suggested by the Korean Thyroid Imaging Reporting and Data System (K-TIRADS) guidelines. Materials and Methods: A total of 463 LNs from 399 patients with DTC who underwent preoperative CT staging and ultrasound-guided fine-needle aspiration were included. The following CT features for each LN were evaluated: absence of hilum, cystic changes, calcification, strong enhancement, and heterogeneous enhancement. Multivariable logistic regression analysis was performed to identify independent CT features associated with metastatic LNs, and their diagnostic performances were evaluated. LNs were classified into probably benign, indeterminate, and suspicious categories according to the K-TIRADS and the modified LN classification proposed in our study. The diagnostic performance of both classification systems was compared using the exact McNemar and Kosinski tests. Results: The absence of hilum (odds ratio [OR], 4.859; 95% confidence interval [CI], 1.593-14.823; P = 0.005), strong enhancement (OR, 28.755; 95% CI, 12.719-65.007; P < 0.001), and cystic changes (OR, 46.157; 95% CI, 5.07-420.234; P = 0.001) were independently associated with metastatic LNs. All LNs showing calcification were diagnosed as metastases. Heterogeneous enhancement did not show a significant independent association with metastatic LNs. Strong enhancement, calcification, and cystic changes showed moderate to high specificity (70.1%-100%) and positive predictive value (PPV) (91.8%-100%). The absence of the hilum showed high sensitivity (97.8%) but low specificity (34.0%). The modified LN classification, which excluded heterogeneous enhancement from the K-TIRADS, demonstrated higher specificity (70.1% vs. 62.9%, P = 0.016) and PPV (92.5% vs. 90.9%, P = 0.011) than the K-TIRADS. Conclusion: Excluding heterogeneous enhancement as a suspicious feature resulted in a higher specificity and PPV for diagnosing metastatic LNs than the K-TIRADS. Our research results may provide a basis for revising the LN classification in future guidelines.

• Nuclear Medicine and Molecular Imaging
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• 제41권1호
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• pp.22-29
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• 2007

목적: 방사성옥소를 잘 섭취하는 갑상선 전이암들은 낮은 FDG 섭취를 보이나, 방사선옥소를 섭취하지 않는 경우는 FDG PET에서 잘 보인다고 알려져 있다. 본 연구에서는 원발성 갑상선 유두상암의 FDG 섭취 양상이 어떠한지 알아보고자 하였다. 대상 및 방법: 초음파유도하 세침흡입술로 갑상선 유두상암을 진단을 받고 갑상선 전절제술이 예정되었던 환자 40명들이 시행한 FDG PET/CT들을 대상으로 후향적 분석을 시행하였다. FDG 섭취의 정도는 병변이 주변 조직보다 높은 섭취를 보이는 것을 육안적으로 확인할 수 있는 경우 양성으로 하고 그렇지 않은 경우 음성으로 나누었으며, 병변의 최대 표준화섭취계수(peak SUV)를 구하여 그 크기와 비교하였다. 결과: FDG 섭취 양성소견을 보이는 27례의 갑상선 유두상암들의 평균 크기는 $1.9{\pm}1.4\;cm\;(0.5{\sim}5\;cm)$였고, FDG 섭취를 보이지 않는 13례의 경우는 $0.4{\pm}0.2cm\;(0.2{\sim}0.9\;cm)$이었다. 갑상선의 크기가 1 cm 이상인 19례들은 ($2.5{\pm}1.4\;cm,\;1{\sim}5\;cm$) 모두 FDG 섭취 양성소견을 보였다 (19/19, peak $SUV\;=\;6.4{\pm}5.7,\;1.7{\sim}22.7$). 1cm 미만의 21례의 미세갑상선암들 중 8례가 FDG 섭취 양성소견을 보인 반면 (8/21, peak $SUV\;=\;2.9{\pm}1.3,\;1.7{\sim}5.5$), 13례는 음성소견을 보였다(peak $SUV\;=\;1.2{\pm}0.2,\;1.1{\sim}1.7$). 미세갑상선암들 중 FDG 섭취 양성 소견을 보이는 경우의 크기는 $0.7{\pm}0.1\;cm$으로 음성소견을 보이는 경우의 크기 $0.4{\pm}0.2\;cm$와 비교하여 유의하게 컸다(P=0.01). 결론: 본 보고에서 40례의 원발성 갑상선 유두상암 가운데 1 cm 이상 크기의 갑상선 유두상암들은 모두 FDG 섭취 양성소견을 보였는데, 이는 방사성옥소를 섭취하지 않는 분화도가 나쁜 갑상선암들만 FDG 섭취를 보인다는 이전 문헌의 내용과 상충되며, 이러한 원발성 갑상선 유두상암의 FDG 섭취를 이해하기 위해서는 GLUT 및 NIS 발현과 연관한 후속 연구가 필요하겠다.

• 대한방사선기술학회지:방사선기술과학
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• 제44권3호
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• pp.195-203
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• 2021

Although intra oral dental x-ray is a lower dose than other radiological examinations, pediatric patients are known to have a higher risk of radiation damage than adults. For this reason, pediatric dental x-ray requires management of dose evaluation and imaging conditions during the examination. In this study, the dose calculation program ALARA-Dental(child/adult) was used to evaluate the organ dose and effective dose exposed to each examination site during intra oral imaging of children during dental radiographic examination, and dose analysis according to the imaging conditions was performed. As a result, the highest organ dose distribution was shown at 0.044 ~ 0.097 mGy in all are as of the mucous membrane of oral cavity except for the maxillary incisors and canines. Also, in the case of the thyroid gland, the maxillary canine and maxillary premolar examination showed 0.027 and 0.020 mGy, respectively, and the dose distribution was 15.4% to 70.0% higher than that of the mandibular examination. As for the effective dose calculated during intra oral imaging, the maxillary anterior and canine examinations showed the highest effective doses of 0.005 and 0.004 mSv, respectively, and the maxillary area examination showed a higher dose distribution on average than the mandible.

• 핵의학기술
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• 제12권1호
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• pp.49-56
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• 2008

Purpose: Whole body imaging with radioiodine can detect functioning metastases. Non-physiologic I-131 uptake detected on images usually is interpreted as suggesting functioning thyroid metastases. However, extra-thyroidal I-131 accumulation does not always imply thyroid cancer metastases and has been reported in many circumstances. In order to avoid unnecessary therapeutic interventions it is important to distinguish false-positive sites of I-131 localization. We study here to remove false-positive sites around esophagus region on I-131 whole body imaging in patients who were administrated thyroidectomy. Materials and Methods: From April to August in 2007, we had the patients who had visited our department after they received thyroidectomy due to thyroid cancer. They were given I-131, and performed radioiodine body scan after 41 to 50 hours. Patients were whole-body-scanned for the speed of 8 cm per minute. After that, we took anterior and posterior static images around the patients' neck measured by 300 thousand counts per image. We selected 44 patients who had hot spots around neck region, we divided the patients into two groups. One group was given 0.5 L of water and the other group was given 0.5 L of water with 1 g of Vitamin C dissolved. The patients were asked to drink the fluid for one minute in sitting position and after that, we measured 300 kilo counts per image again. We compared prior anterior, posterior static images with anterior, posterior images after the patients had water or water that Vitamin C resolved. Results: In using water, both observer 1 and 2 interpreted 6 patients were washed out. In the water with Vitamin C resolved, observer 1 and 2 interpreted 9 and 8 patients were washed out. Observer 1 and 2 interpreted 6 and 5 patients had 'indeterminate' when they used water. Both observer 1 and 2 interpreted 6 patients had 'indeterminate' when they used water with Vitamin C resolved. When they used water, observer 1 interpreted 10 patients had 'unchanged' and observer 2 interpreted 11 patients had 'unchanged'. Differently, when they used water with vitamin C resolved, observer1 had 8 patients having 'unchanged'and observer 2 had 9. Conclusion: As a result, by making patients drink 0.5 liter of water which has vitamin C resolved helped getting rid of false-positive sites in esophagus. Therefore, based on this study, we believe that drinking water with vitamin C dissolved is very in terms of reducing false-positive hot spot around the esophagus for the iodine-131 whole body scan.

• 대한두경부종양학회지
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• 제22권1호
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• pp.3-7
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• 2006

Purpose: The nonrecurrent laryngeal nerve(NRLN) is a rare anomaly that is associated with the developmentally aberrant subclavian artery. Although rare on the right side and exceptional on the left, an aberrant nonrecurrent pathway for RLN represents a major surgical risk. Three course variations of right NRLN can be distinguished: descending(type I) , horizontal(type II), ascending(type III). This study is performed to characterize the variations of NRLN, associated vascular anomaly, and proper surgical methods for preventing nerve damage. Materials and Methods: Between January 1998 and March 2006 3,381 thyroidectomy were performed at our institution, and during these operations a nonrecurrent laryngeal nerve was observed in 13 cases (0.38%). There were 1 men and 12 women with a median age of 48 years(range 28-57). All of them are identified on the right side. Results: In all cases, there were no clinical symptoms observed preoperatively. The nerve anomaly was diagnosed preoperatively in only one case. There were type I variations of right RLN in 2 cases and type II variations in 11 cases. The retroesophageal aberrant right subcalvian artery; no innominate(brachiocephalic) artery was found and the right common carotic artery was arising directly from the aortic arch, was seen in 12 cases. A vocal cord palaysis caused by NRLN damage during operation was observed in one patient(7.6%) , where the nerve was close to the superior thyroid artery. No other complications were noted. Conclusion: It can be possible to predict NRLN from signs associated with the vascular anomaly; clinical symptoms or imaging studies. When an vascular anomaly is not detected preoperatively, overlooking possibility of NRLN may lead to severe operative morbidity. Hence, It is most important to identify all the thyroid structures carefully during thyroid surgery and to be aware of the possibility of anatomic variations of RLN.

• Asian Pacific Journal of Cancer Prevention
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• 제17권7호
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• pp.3357-3362
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• 2016

Purpose: To correlate ultrasonographic (US) features of medullary thyroid carcinoma (MTC) with preoperative and post-operative calcitonin levels. Materials and Methods: A total of 130 thyroid nodules diagnosed as MTC were evaluated. Two radiologists retrospectively evaluated preoperative US features according to size, shape, margin, echogenicity, type of calcification, and lymph node status. Postoperative clinical and imaging follow-up (mean duration $31.9 {\pm} 22.5$ months) was performed for detection of tumor recurrence. US features, presence of LN metastasis, and tumor recurrence were compared between MTC nodules with and without elevated preoperative calcitonin (>100 pg/mL). Those with normalized and non-normalized postoperative calcitonin levels groups were also compared. Results: Common US features of MTCs were solid internal content (90.8%), irregular shape (44.6%), circumscribed margin (46.2%), and hypoechogenicity (56.2%). Comparing MTC nodules with and without elevated preoperative calcitonin levels, the size and shape of MTC nodule and lymph node metastasis showed statistical significance (p<0.05). Postoperative calcitonin normalization correlated with US features of tumor size (p=0.002), margin (p=0.034), shape ($p{\leq}0.001$), and presence of calcification (p=0.046). Tumor recurrence and LN metastasis were more prevalent in patients without normalization of postoperative calcitonin than in those with normalization (p=0.001). Conclusions: Serum calcitonin measurement is helpful for early diagnosis and predicting prognosis. Postoperative calcitonin measurement is also important for postoperative US follow up, especially in cases with larger nodule size, presence of calcification, irregular shape, and irregular margin.

• 대한핵의학회지
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• 제29권4호
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• pp.526-532
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• 1995

두경부의 악성 종양의 진단에서 $^{99m}Tc$-(V)-DMSA 영상술은 비교적 높은 양성율을 보여 주었고 (Planar 65%, SPECT 90%), 원격 전이부위의 영상진단에도 도움이 되었다. 그러나 $^{99m}Tc$-(V)-DMSA는 두경부의 양성 병변에도 섭취가 될 수 있어, 판독 시 임상검사 및 다른 영상소견과의 비교검토가 필요할 것으로 판단된다.

• 대한방사성의약품학회지
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• 제6권1호
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• pp.3-9
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• 2020

Tetraiodothyroacetic acid (tetrac) is a derivative of thyroid hormone T₄ and causes anti-angiogenesis by blocking T₄ binding to integrin α_vβ₃. In this study, we synthesized [^99mTc]Tc-Cys-Asp-Gly(CDG)-tetrac and evaluated it in vitro as a tumor angiogenesis imaging ligand. The CDG was conjugated to tetrac as a chelator for technetium-99m labeling. The cold vial containing CDG-tetrac, sodium glucoheptonate, and reducing agent was completed under nitrogen-filled atmospheric glove bag. [^99mTc]Tc-CDG-tetrac was synthesized in quantitative yield by heating the cold vial with [^99mTc]TcO₄^- at 100℃ for 30 min. In vitro serum stability of [^99mTc]Tc-CDG-tetrac was measured by incubating the radioligand in 50% fetal bovine serum at 37℃ and analyzing the incubation mixture by radio-TLC, which showed high stability over 6 h (≥ 98%). Cell binding study was carried out by incubating [^99mTc]Tc-CDG-tetrac with human umbilical vein endothelial (HUVE) cells at 37℃ for 6 h. The cell binding of the radioligand increased from 100% at 0.5 h to 293.7% at 6 h in a time-dependent manner. For blocking study, the cells were incubated with the radioligand in the presence of either tetrac (20 μM) or cRGDyK (20 μM) at 37℃ for 4 h. The results demonstrated that the cell binding of the radioligand was inhibited by tetrac (19.1%) or cRGDyK (35.6%), indicating specific binding of the radioligand to integrin α_vβ₃. Thus, this study suggests that [^99mTc]Tc-CDG-tetrac may be a potential radioligand for tumor angiogenesis imaging.

• Imaging Science in Dentistry
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• 제34권4호
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• pp.219-223
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• 2004

Metastases to the jawbones are found predominantly in the mandible and are rare in relation to the overall spectrum of oral malignancy. Analysis of the literature shows that the most frequent primary sites are the breast, lung, kidney, thyroid, and prostate. Adenocarcinoma of the mandible, whether primary or metastatic, are usually difficult to diagnose clinically. We report a case illustrating the clinical, radiographic, and histologic findings of a metastatic lung adenocarcinoma of the anterior mandible in a 58-year-old male.