최근 핵의학 영상 기기 발전 동향

김병태(Byung Tae Kim),김상은(Sang Eun Kim),김준영(Joon Young Kim),최용(Yong Choi),이경한(Kyung Han Lee),최연성(Yearn Seong Choe),김종호(Jong Ho Kim),임기천(Ki Chun Im) 대한핵의학회 1998 핵의학 분자영상 Vol.32 No.6

The goals of developments in nuclear medicine instrumentation are to offer a higher-quality image and to aid diagnosis, prognosis assessment or treatment planning and monitoring. It is necessary for physicists and engineers to improve or design new instrumentation and technique, and to implement, validate, and apply these new approaches in the practice of nuclear medicine. The researches in physical properties of detectors and crystal materials and advance in image analysis technology have improved quantitative and diagnostic accuracy of nuclear medicine images. This review article presents recent developments in nuclear medicine instrumentation, including scatter and attenuation correction, new detector technology, tomographic image reconstruction methods, 511 keV imaging, dual modality imaging device, small gamma camera, PET developments, image display and analysis methods.

소형 감마카메라 제작에 사용되는 NaI(TI)- 광전자증배관 검출기의 민감도와 위치 분해능 특성 연구를 위한 몬테카를로 시뮬레이션

김종호,최용,김준영,임기천,김상은,최연성,주관식,김영진,김병태,Kim, Jong-Ho,Choi, Yong,Kim, Jun-Young,Im, Ki-Chun,Kim, Sang-Eun,Choi, Yeon-Sung,Joo, Kwan-Sik,Kim, Young-Jin,Kim, Byung-Tae 한국의학물리학회 1997 의학물리 Vol.8 No.2

본 연구에서는 유방암 진단용 감마카메라 제작 시에 고려되어야 하는 섬광체의 크기와 섬광체 면의 적절한 표면처리가 카메라의 민감도와 위치 분해능에 미치는 영향을 연구하기 위하여 섬광의 광학적 특성을 몬테카를로(Monte Carlo) 시뮬레이션 방법을 이용하여 고찰하였다. 섬광체는 NaI(TI) 결정체로 크기가 60 mm $\times$ 60 mm $\times$ 6 mm이며, 발생한 섬광이 광전자증배관의 광음극에 도달할 때까지를 시뮬레이션 하였다. 섬광체 표면 처리를(5가지 : Ground,. Polished, Metal-0.95RC(반사계수), Polished-0.98RC, Painted-0.98RC) 변화시켜 민감도를 계산하였다. 섬광체와 광전자증배관 (photomultiplier tube, PMT)의 접합면에 사용되는 물질의 굴절률 변화에 따른 민감도와 NaI(TI) 섬광체 창으로 많이 사용되고 있는 유리의 두께 변화에 따른 민감도를 조사하였다. 또한 섬광 결정체의 내인성 위치 분해능(intrinsic position resolution)을 섬광이 발생된 후 섬광 퍼짐(light spread) 정도를 시뮬레이션 함으로써 고찰하였다. 감마선의 입사면을 각각 Ground, Polished, Metal-0.95RC, Polished-0.98RC, Painted-0.98RC로 표면처리 하였을 때 민감도가 70.9%, 73.9%, 78.6%, 80.1%, 85.2%로 나타나 Painted-0.98RC일 때 민감도가 가장 우수하였다. 섬광체와 광전자증배관의 접합에 사용된 물질의 굴절률이 증가할수록 민감도가 증가하였으며 매질이 두꺼울수록 민감도는 저하되었다. 디자인된 검출기의 내인성 위치분해능은 수직, 수평 방향으로 약 1.2 mm로 예측되었다. 이 연구에서는 감마카메라의 성능에 직접적인 영향을 미치는 NaI (Tl)-PMT의 민감도와 위치 분해능을 몬테카를로 시뮬레이션을 통해 예견할 수 있었으며, 본 연구결과 NaI(TI)-PMT를 이용한 검출기가 고민감도ㆍ고해상력이 요구되는 유방암 진단용 소형 감마카메라 제작에 적합하다고 판단된다. We studied optical behavior of scintillation light generated in NaI(TI) crystal using Monte Carlo simulation method. The simulation was performed for the model of NaI(TI) scintillator (size: 60 mm ${\times}$ 60 mm ${\times}$ 6 mm) using an optical tracking code. The sensitivity as a function of surface treatment (Ground, Polished, Metal-0.95RC, Polished-0.98RC, Painted- 0.98RC) of the incident surface of the scintillator was compared. The effects of NaI(TI) scintillator thickness and the refractive index of light guide optically coupling between the NaI(TI) scintillator and photomultiplier tube (PMT) were simulated. We also evaluated intrinsic position resolution of the system by calculating the spread of scintillation light generated. The sensitivities of the system having the surface treatment of Ground, Polished, Metal-0.95RC, Polished-0.98RC and Painted-0.98RC were 70.9%, 73.9%, 78.6%, 80.1% and 85.2%, respectively, and the surface treatment of Painted-0.98RC allowed the highest sensitivity. As increasing the thickness of scintillation crystal and light guide, the sensitivity of the system was decreased. As the refractive index of light guide increases, the sensitivity was increased. The intrinsic position resolution of the system was estimated to be 1.2 mm in horizontal and vertical directions. In this study, the performance of NaI(TI)-PMT detector system was evaluated using Monte Carlo simulation. Based on the results, we concluded that the NaI(TI)-PMT detector array is a favorable configuration for small gamma camera imaging breast tumor using Tc-99m labeled radiopharmaceuticals.

NaI ( T1 ) 섬광결정과 위치민감형 광전자증배관을 이용한 유방암 진단용 소형 감마카메라 개발

김종호,최용,권홍성,김희중,김상은,최연성,이경한,김문회,주관식,김병태 ( Jong Ho Kim,Yong Choi,Hong Seong Kwon,Hee Joung Kim,Sang Eun Kim,Yearn Seong Choe,Kyung Han Lee,Moon Hae Kim,Koan Sik Joo,Byung Tae Kim ) 대한핵의학회 1998 핵의학 분자영상 Vol.32 No.4

Purpose: The conventional gamma camera is not ideal for scintimammography because of its large detector size ( 500 mm in width) causing high cost and low image quality. We are developing a small gamma camera dedicated for breast imaging. Materils and Methods: The small gamma camera system consists of a NaI (Tl) crystal (60 mm X60 mm X6 mm) coupled with a Hamamatsu R3941 Position Sensitive Photomultiplier Tube (PSPMT), a resister chain circuit, preamplifiers, nuclear instrument modules, an analog to digital converter and a personal computer for control and display. The PSPMT was read out using a standard resistive charge division which multiplexes the 34 cross wire anode channels into 4 signals (X, X, Y, Y ). Those signals were individually amplified by four preamplifers and then, shaped and amplified by amplifiers. The signals were discriminated and digitized via triggering signal and used to localize the position of an event by applying the Anger logic. Results: The intrinsic sensitivity of the system was approximately 8,000 counts/.'ec/pCi. High quality flood and hole mask images were obtained. Breast phantom containing 2-7 mm diameter spheres was successfully imaged with a parallel hole collimator. The image displayed accurate size and activity distribution over the imaging field of view. Conclusion: We have succesfully developed a small gamma camera using NaI(T1)-PSPMT and nuclear instrument modules. The small gamma camera developed in this study might imprnve the diagnostic accuracy of scintimammography by optimally imaging the breast. (Korean J Nucl Med 1998;32:365-73)

젖소에서 유성분 분석을 통한 우군 건강관리프로그램의 개발

문진산,손창호,이보균,주이석,강현미,김종만,김병태,문현식,Moon, Jin-San,Son, Chang-Ho,Lee, Bo-Kyeun,Joo, Yi-Seok,Kang, Hyun-mi,Kim, Jong-Man,Kim, Byoung-Tae,Moon, Hyun-Sik 대한수의학회 2002 大韓獸醫學會誌 Vol.42 No.4

The purpose of this study was to develope a computer program to help with gross diagnosis of protein-energy balance and feeding management practice and with the prediction about the risk possibility of productive disease such as reproductive and metabolic disorders by evaluating fat, protein, and milk urea nitrogen (MUN) from individual cow milk in dairy herd Somatic cell counts also represent the condition of udder health. The principal flow charts of this program was to check on herd management, sampling the composite milk, analysis the milk composition, conversion of data from milking equipment to program, input and analysis of data in program, and report. This program is compatible with window 95/98 system. The major analytical elements of this program were presented as; the profile of herd lactation curve analysis of the test-day milk production level, the distribution of somatic cell count, the fat to protein ratio to evaluate body energy balance, and the interpretation of dietary protein-energy balance by milk protein and MUN contents for individual cows. This program using milk fat, protein, MUN, and somatic cell counts will serve as a monitoring tool for the protein-energy balance and the feeding management practice, and for distribution of mastitis in individual cows. It will also be used to manage the nutritional and reproductive disorders and mastitis at the farm level.

태권도 선수의 발차기 수행력이 등속성 근기능과 무산소 파워에 미치는 영향

정현주(Jung, Hyun-joo),최동재(Choi, Dong-jae),김병태(Kim, byung-tae),이상호(Lee, Sang-ho),김종호(Kim, Jong-ho),정정욱(Jung, Jeong-wook) 한국코칭능력개발원 2012 코칭능력개발지 Vol.14 No.2

기능성 소화불량증에서 Helicobacter pylori 감염이 위근위부 운동기능에 미치는 영향

김영호,박정미,손희정,최준영,김재준,최규완,백승운,고광철,이풍렬,이종철,김병태,심상군,김창섭 대한소화기학회 1999 대한소화기학회지 Vol.34 No.2

Background/Aims: Little is known about the effect of Helicobacter pylori (HP) infection on proximal gastric motor function in functional dyspepsia (FD). We evaluated total gastric emptying, initial proximal gastric distribution of meal (IPGD), proximal gastric emptying, basal tone, compliance and postprandial accommodation in the patients with FD relating to HP status. Methods: Of 25 subjects, 18 were HP positive and 7 were HP negative by the result of 13C urea breath test. A solid-phase scintigraphic gastric emptying and gastric barostat were performed. Results: In both HP-positive and HP-negative patients, sex, age, symptom score and body mass index were not different. Total gastric half-emptying time (101±13.9 min vs. 107±25.9 min), retention rate at 30 min (80.4±1.2% vs. 81.6±3.2%) and at 120 min (47.3±4.1% vs. 49.9±7.7%) were similar between the two groups. IPGD (69.4±4.1% vs. 64.6±11.1%) and proximal half-emptying time (37.9±5.2 min vs. 48.4±13.2 min) were not different between the two groups. basal tone (60.8±3.4 ml vs. 65.0±7.0 ml), compliance (49.2±2.4 ml/mmHg vs. 37.6±5.7 ml/mmHg), and accommodation (207±46% vs. 137±75%) were not different between the two groups. Conclusions: There was no association between HP infection and proximal gastric motor function in FD.

NaI(Tl) 섬광결정과 위치민감형 광전자증배관을 이용한 소형 감마카메라의 신호 특성 고찰

주관식,김준영,이경한,최용,김병태,김종호,김상은,최연성,임기천 대한핵의학회 2000 핵의학 분자영상 Vol.34 No.1

Purpose: We characterized the signals obtained from the components of a small gamma camera using NaI(Tl)-position sensitive photomultiplier tube (PSPMT) and optimized the parameters employed in the modules of the system. Materials and Methods: The small gamma camera system consists of a NaI(Tl) crystal (60×60×6 mm3) coupled with a Hamamatsu R3941 PSPMT, a resister chain circuit, preamplifiers, nuclear instrument modules (NIMs), an analog to digital converter and a personal computer for control and display. The PSPMT was read out using a resistive charge division circuit which multiplexes the 34 cross wire anode channels into 4 signals (X+, X­, Y+, Y­). Those signals were individually amplified by four preamplifiers and then, shaped and amplified by amplifiers. The signals were discriminated and digitized via triggering signal and used to localize the position of an event by applying the Anger logic. The gamma camera control and image display was performed by a program implemented using a graphic software.ults: The characteristics of signal and the parameters employed in each module of the system were presented. The intrinsic sensitivity of the system was approximately 8×103 counts/sec/μCi. The intrinsic energy resolution of the system was 18% FWHM at 140 keV. The spatial resolution obtained using a line-slit mask and 99mTc point source were, respectively, 2.2 and 2.3 mm FWHM in X and Y directions. Breast phantom containing 2∼7 mm diameter spheres was successfully imaged with a parallel hole collimator. The image displayed accurate size and activity distribution over the imaging field of view. Conclusion: We proposed a simple method for development of a small gamma camera and presented the characteristics of the signals from the system and the optimized parameters used in the modules of the small gamma camera. (Korean J Nucl Med 2000;34:82-93)