Perfusion Scintigraphy for the Evaluation of Patients with Raynaud’s Phenomenon

정아리 대한핵의학회 2020 핵의학 분자영상 Vol.54 No.6

Raynaud’s phenomenon (RP) is a functional vascular disorder, which can be defined as transient vasospasm of the peripheral arteries and arterioles in the affected areas exposed to the cold or other stress. The diagnosis of RP is mainly based on symptoms. Perfusion scintigraphy, with or without cold stimulation, can be used to evaluate RP. Studies with perfusion scintigraphy for RP have shown that patients with RP showed lower finger-to-palm ratio than patients without RP. Responses after cold stimulation were also different in patients with RP. Not only decreased perfusion or blood pool after cold stimulation but also paradoxically increased perfusion can be shown in patients with RP. Some studies have shown that primary and secondary RP can be differentiated by perfusion scintigraphy. Correlation between duration of disease and findings on perfusion scintigraphy was reported. Perfusion scintigraphy can show differences before and after treatment as well. However, the protocols for perfusion scintigraphy for PR vary among studies. The standard protocol of perfusion scintigraphy for RP should be established.

Conversion to Paradoxical Finding on Technetium-99m-labeled RBC Scintigraphy after Treatment for Secondary Raynaud’s Phenomenon

정아리,하정민,송호천,김자혜,최수진나 대한핵의학회 2013 핵의학 분자영상 Vol.47 No.4

An 18-year-old woman reported that after exposure to cold temperatures her fingers appeared blue and her hands and feet felt cold. Secondary Raynaud’s phenomenon (RP)associated with peripheral vascular disease was suspected. Technetium (Tc)-99m-labeled RBC hand scintigraphy after cold change showed decreased blood pool activity in her fingers. The patient’s symptoms improved after she received sarpogrelate HCL (200 mg/day) and nifedifine (40 mg/day). Follow-up scintigraphy performed 7 months after the patient started treatment showed paradoxically increased blood pool activity in her fingers after cold challenge. To the best of our knowledge, this is the first case report of a patient with secondary RP showing paradoxical change on scintigraphy after she received medication that improved her symptoms.

Preoperative Lymph Node Staging by FDG PET/CT With Contrast Enhancement for Thyroid Cancer: A Multicenter Study and Comparison With Neck CT

정아리,하정민,한연희,공은정,최연정,홍기환,박준희,김성훈,박정미 대한이비인후과학회 2017 Clinical and Experimental Otorhinolaryngology Vol.10 No.1

Objectives. The purpose of this study was to compare lymph node (LN) staging using 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) with contrast-enhancement (CE) PET/CT and contrast-enhanced neck CT (neck CT) in patients with thyroid cancer with level-by-level comparison with various factors. Methods. This was a retrospective multicenter study. A total of 85 patients were enrolled. Patients who underwent a preoperative evaluation by CE PET/CT and neck CT for thyroid cancer were enrolled. The gold standard for LN was the combination of surgical pathology and clinical follow-up. We compared CE PET/CT with neck CT using a level-by-level method. Factors, including age, sex, camera, arm position, tumor size, extra-thyroidal extension, tumor location, number of primary tumors, primary tumor maximum standardized uptake value, and the interval from scan to operation were also analyzed. Results. Overall accuracy was 81.2% for CE PET/CT and 68.2% for neck CT. CE PET/CT was more sensitive than neck CT (65.8% vs. 44.7%). Also, CE PET/CT showed higher negative predictive value (77.2% vs. 66.1%). CE PET/CT showed good agreement with the gold standard (weighted kappa [κ], 0.7) for differentiating N0, N1a, and N1b, whereas neck CT showed moderate agreement (weighted κ, 0.5). CE PET/CT showed better agreement for the number of levels involved with the gold standard (weighted κ, 0.7) than that of neck CT with the gold standard (weighted κ, 0.5). The accuracies for differentiating N0, N1a, and N1b were 81.2% for CE PET/CT and 68.2% for neck CT. Level-by-level analysis showed that CE PET/CT was more sensitive and has higher negative predictive value for detecting ipsilateral level IV and level VI LNs than neck CT. Other analyzed factors were not related to accuracies of both modalities. Conclusion. CE PET/CT was more sensitive and reliable than neck CT for preoperative LN staging in patients with thyroid cancer.

제왕절개 마취시 태아만출전 사용된 Sevoflurane이 산모의 Bispectral Index (BIS)와 신생아에 미치는 영향

정아리,김동연,이희승,한종인,정락경,김치효,이귀용 대한마취과학회 2004 Korean Journal of Anesthesiology Vol.47 No.2

Multiple Diagnostic Imaging of a Patient with Solid Pseudopapillary Tumour of the Pancreas: EUS, CT and FDG PET/CT

정아리,하정민,권성영 대한핵의학회 2014 핵의학 분자영상 Vol.48 No.1

46차 대한핵의학회 추계학술대회 포스터 : 폐암 환자에서 선행 유도 화학 요법 유무에 따른 F-18 FDG PET/CT 진단률의 차이

정아리,정신영,하정민,서영순,권성영,민정준,송호천,김영철,나국주,최찬,범희승 대한핵의학회 2007 핵의학 분자영상 Vol.41 No.5

Clinical Usefulness of 18F-FDG PET/CT in the Detection of Early Recurrence in Treated Cervical Cancer Patients with Unexplained Elevation of Serum Tumor Markers

정아리,하정민,정신영,송호천,민정준,범희승,최호선 전남대학교 의과학연구소 2013 전남의대학술지 Vol.49 No.1

We investigated the diagnostic value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) for restaging of treated uterine cervix squamous cell cancer with tumor maker elevation that was not explained by other conventional evaluation. We enrolled 32 cases who underwent PET/CT for the restaging of treated cervical cancer with tumor marker elevation that was not explained by recent conventional evaluation. All enrolled cases had squamous cell carcinoma. Increased tumor markers included squamous cell carcinoma antigen (SCC Ag) and carcinoembryonic antigen (CEA). PET/CT findings were determined by pathologic confirmation or clinical follow-up. We compared PET/CT accuracy and clinical parameters including normalization of tumor markers in both the SCC Ag elevation group and the CEA elevation group. The sensitivity, specificity, positive predictive value, and negative predictive value of PET/CT in detecting recurrence were 100%, 83.3%, 82.4%, and 100%,respectively. Accuracy was significantly different between the SCC Ag elevation group and the CEA elevation group (p=0.0169). PET/CT with SCC Ag elevation was more accurate (100%) than PET/CT with CEA elevation (66.7%). Normalization of tumor markers was observed more often in the SCC Ag elevation group than in the CEA elevation group (p=0.0429). PET/CT showed high negative predictive value and sensitivity in the restaging of cervical cancer with unexplained tumor marker elevation. PET/CT was more accurate in patients with SCC Ag elevation than in those with CEA elevation.

Recent Survey of Effective Doses of F-18 FDG Torso PET/CT in Korea and the Current Recommendations for CT Protocols of PET/CT

정아리,박정미,박경준,김용일,권현우,이은성,남기표,이호영,이홍재,유익동,어재선,김지영,윤준기,김경민,김성민,김태성 대한핵의학회 2020 핵의학 분자영상 Vol.54 No.5

Purpose This study aimed to construct a database of the effective doses (ED) from F-18 fluorodeoxyglucose (FDG) torso positron emission tomography/computed tomography (PET/CT) in Korea to provide data that supports the reduction of the CT dose of PET/CT and optimization of PET/CT protocols in Korea. Methods We investigated data of ED and CT parameters of FDG PET/CT. The data were analyzed by body weight groups. Results A total of 31 hospitals participated in the survey (99 adults). The mean total EDs (± SD) were 8.77 ± 2.76, 10.93 ± 3.14, and 12.57 ± 3.79 mSv for the 55-, 70-, and 85-kg groups, respectively. The FDG EDs were 4.80 ± 0.98, 6.05 ± 1.15, and 6.89 ± 1.52 mSv, and the CT EDs were 4.00 ± 2.12, 4.88 ± 2.51, and 5.68 ± 2.89 mSv, respectively. Of the enrolled hospitals, 54.5% used ultra-low-dose CT protocols, and their CT ED was significantly lower than low-dose CT group in all groups (2.9 ± 1.0, 3.2 ± 1.1, and 3.3 ± 1.0 mSv vs. 6.6 ± 1.6, 7.2 ± 2.1, and 7.9 ± 2.2 mSv, all p < 0.001, respectively). In the ultra-low-dose CT group, the CT ED with the iterative reconstruction was significantly lower than that of CT without iterative reconstruction in the 55-kg group (2.4 ± 0.9 vs. 3.3 ± 0.9, p = 0.04). Conclusions These results and current recommendations can be helpful for optimizing PET/CT diagnostic reference level (DRL) and reducing unnecessary PET/CT radiation exposure.

Changes in 18F-Fluorodeoxyglucose Uptake in the Spinal Cord in a Healthy Population on Serial Positron Emission Tomography/Computed Tomography

정아리,하정민,송호천,변병현,홍선표,민정준,범희승,이정길 전남대학교 의과학연구소 2013 전남의대학술지 Vol.49 No.1

We aimed to determine the changes in 18F-fluorodeoxyglucose (FDG) uptake in the spinal cord on two serial positron emission tomography/computed tomography (PET/CT)scans in a healthy population. We retrospectively enrolled healthy people who underwent PET/CT twice for cancer screening. We excluded those who had degenerative vertebral disease, neurologic disease, or a history of a vertebral operation. The standardized uptake value (SUVmax) of the spinal cord of each mid-vertebral body was obtained by drawing a region of interest on an axial image of PET/CT. For analysis, the cord-to-background ratio (CTB) was used (CTB=SUVmax of each level/SUVmax of L5level). Differences in pattern, sex, age, and intervals of the two serial PET/CT scans were analyzed. A total of 60 PET/CT images of 30 people were analyzed. The mean interval between the two PET/CT imaging studies was 2.80±0.94 years. On the follow-up PET/CT, significant change was shown only at the level of the C6 and T10 vertebrae (p<0.005). Mean CTB showed a decreasing pattern from cervical to lumbar vertebrae. There were two peaks at the lower cervical level (C4-6) and at the lower thoracic level (T12). Neither sex nor age significantly affected CTB. The FDG uptake of the spinal cord changed significantly on follow-up PET/CT only at the level of the C6 and T10vertebrae. This finding is valuable as a baseline reference in the follow-up of metabolic changes in the spinal cord.

곡선부 초고속주행 시 고령 운전자의 횡방향 주행안전성 평가 연구

정아람,장지용,박현진,오철 대한교통학회 2021 대한교통학회지 Vol.39 No.3

Understanding of driving behaivor in the high-speed driving environment of 140km/h based on scientific analyses is the basis to derive effective safety countermeasures for the crash prevention. In particular, the lateral driving behavior in the horizontal curves by the driver’s driving ability is an important element in safety analysis. Elderly drivers, in general, have lower physical and congnitive capabilities than non-elderly drivers. Therefore, it is necessary to evaluate the driving safety of an elderly driver when driving in horizontal curves at high-speed conditions. The purpose of this study is to derive effective evaluation indicators to represent the lateral driving safety of elderly drivers, and to identify unsafe road sections based on the analysis of derives indicators. A large-scale driving simulator equipped with a real-time vehicle dynamics simulation system was used for conducting driving simulation experiments with 71 participants. Both the rate of run-off the lane and the standard deviation of lateral acceleration were identified as promising indicators to evaluate the lateral safety of elderly drivers. Regarding the unsafe road sections, it was found that road segments including horizontal curves less than 3,000m of curve radius, downhill, convex slope, and a continuous tunnel sections would negatively affect expected to be used as fundamentals for traffic safety management strategies to address elderly driver’s safety in high-speed driving conditions. 140km/h 수준의 초고속주행 환경에서 운전자의 주행행태를 과학적으로 분석하고 이해하는 것은 교통사고 예방을 위한 도로설계 및 안전시설 설치의 근간이 된다. 운전자의 주행능력에 따른 곡선부에서의 운전자 횡방향 주행행태 변화는 안전성 분석 시 중요한 평가대상이다. 일반적으로 고령 운전자의 경우 비고령 운전자보다 신체적 능력 및 인지 ‧ 판단 능력이 저하되므로 횡방향 주행행태가 주행안전성에 영향을 미칠 수 있다. 따라서 곡선부 초고속주행 시 고령 운전자에 대한 주행안전성 평가가 필요하다. 본 연구의 목적은 곡선부 초고속주행 시 고령 운전자의 횡방향 주행안전성을 나타낼 수 있는 평가지표를 선정하고, 주행안전성 취약구간을 도출하는 것이다. 본 연구의 분석대상은 현재 설계속도 140km/h로 설계되고 공사가 진행중인 서울-세종 고속도로의 안성-용인 구간으로 설정하였으며 실시간 차량 동역학 시뮬레이션 시스템이 탑재된 초대형 도로주행 시뮬레이터를 이용하여 다양한 연령층의 운전자 71명에 대한 주행 데이터를 수집하였다. 연구 결과, 고령 운전자의 주행안전성을 나타낼 수 있는 대표 평가지표를 차로이탈률과 횡방향 가속도 표준편차로 선정하고 설계구간별로 산출된 평가지표에 따라 주행안전성이 취약한 상위 5개의 설계구간을 도출하였다. 주행안전성 취약구간은 주로 평면곡선 반지름이 3,000m 미만이고 내리막 혹은 볼록 경사와 연속터널 구간이 포함되는 것으로 나타났다. 주행안전성 취약구간에서는 고령 운전자의 시인성 저하 및 핸들조작 미숙으로 평면선형의 변화에 적절하게 대응하지 못해 주행안전성이 저조한 것으로 판단된다. 본 연구의 결과는 기존 도로의 제한속도 상향 및 초고속도로 설계에 관한 교통안전관리 방안 마련을 위한 기초자료로 활용될 수 있을 것으로 기대된다.