A Brief History of Nuclear Medicine Physics, Instrumentation, and Data Sciences in Korea

Abstract

We review the history of nuclear medicine physics, instrumentation, and data sciences in Korea to commemorate the 60^th anniversary of the Korean Society of Nuclear Medicine. In the 1970s and 1980s, the development of SPECT, nuclear stethoscope, and bone densitometry systems, as well as kidney and cardiac image analysis technology, marked the beginning of nuclear medicine physics and engineering in Korea. With the introduction of PET and cyclotron in Korea in 1994, nuclear medicine imaging research was further activated. With the support of large-scale government projects, the development of gamma camera, SPECT, and PET systems was carried out. Exploiting the use of PET scanners in conjunction with cyclotrons, extensive studies on myocardial blood flow quantification and brain image analysis were also actively pursued. In 2005, Korea’s first domestic cyclotron succeeded in producing radioactive isotopes, and the cyclotron was provided to six universities and university hospitals, thereby facilitating the nationwide supply of PET radiopharmaceuticals. Since the late 2000s, research on PET/MRI has been actively conducted, and the advanced research results of Korean scientists in the fields of silicon photomultiplier PET and simultaneous PET/MRI have attracted significant attention from the academic community. Currently, Korean researchers are actively involved in endeavors to solve a variety of complex problems in nuclear medicine using artificial intelligence and deep learning technologies.

We review the history of nuclear medicine physics, instrumentation, and data sciences in Korea to commemorate the 60^th anniversary of the Korean Society of Nuclear Medicine. We have compiled this history based on recorded documents and literature, as well as our memories.

We have tried to describe the history in relative detail since the 1990s, when we started working in the Korean nuclear medicine community. We hope that readers will appreciate that the lack of detail in our description of the history before this time due to limited records of the developments prior to 1990. We would also like to state at the outset that this history may not be exhaustive and likely suffers from some errors attributable to our lack of knowledge and experience. We will be very grateful if readers can bring any discrepancies or omissions to our notice, and shall strive to set the record straight at the next available opportunity to chronicle the history of our field.

Early Years of Nuclear Medicine in Korea

The treatment of a patient of hyperthyroidism with radioactive iodine in the Seoul National University Hospital (SNUH) in June 1959 marks the beginning of the field of nuclear medicine in Korea [1]. In 1960, radioisotope clinics and laboratories were established in SNUH and Daegu Dongsan Presbyterian Hospital, leading to active use of radioisotopes for the diagnosis and treatment of diseases [2, 3]. In 1961, the United States Atomic Energy Commission donated nuclear medicine instruments (Tracer Lab's rectilinear scanner, scintillation counter, detector, and spectrometer) to the Seoul National University (SNU), Chonnam National University, Kyungpook National University, and Pusan National University. Subsequently, the Catholic University of Korea St. Mary's Hospital, Daegu Dongsan Hospital, and Severance Hospital also set up their isotope facilities, increasing the number of institutions offering nuclear medicine imaging and therapy in Korea. In 1962, the TRIGA Mark II reactor (100 KW, for research) was put into operation at the Korea Atomic Energy Research Institute and began to produce some isotopes, catalyzing the development of nuclear medicine in Korea [4]. The scintillation camera (Pho-gamma II, Nuclear Chicago), introduced in 1969, opened a new era in nuclear medicine imaging. Scintigraphy scans evolved from static to dynamic imaging with improved spatial resolution, enabling functional studies of the hepatobiliary tract, brain, heart, and kidneys. With the introduction of radioimmunoassay in 1969 and the introduction of a new scintillation gamma counter in SNUH in 1971, radioimmunoassay began to be used in clinical practice [1].

Pioneering Developments in the 1970s and 1980s

The 1970s and 1980s saw the invention and development of tomography technologies such as computed tomography (CT), single photon emission computed tomography (SPECT), and positron emission tomography (PET). In this period, Korean scientists who were active in the United States contributed significantly to the development of nuclear medical imaging device technology and industry. Zang-Hee Cho at UCLA developed the first ring-type PET scanner and introduced the BGO (Bismuth Germanate) scintillation crystal to PET [5, 6], contributing to the development of modern PET scanners. He later served as a professor at the Korea Advanced Institute of Science and Technology (KAIST) from 1978 to 1995, leading MRI, PET, and SPECT research in Korea [7–10]. The GAMMATOM-1 SPECT system developed by his group was the first nuclear medicine camera made in Korea for tomography [9] (Fig. 1). In 2004, he was invited to serve as the director of the Neuroscience Research Institute of Gachon Medical School, where he introduced the 7 T MRI, creating a landmark not just for Korea but for all of Asia, and commenced the development of a 7 T MRI-based PET/MRI hybrid imaging system [11–13]. Chun Bin Lim, who played a pivotal role in the development of the triple-head SPECT system [14, 15], established the Trionix Research Laboratory in the late 1980s, where he commercialized the multi-head SPECT systems, “Triad” and “Biad.” These gamma cameras were received well by users in the USA and also received great attention from the academic community. Their introduction coincided with the advent of radiopharmaceuticals for heart and brain SPECT, such as ^99mTc-sestamibi, ^99mTc-HMPAO, and ¹²³I-IMP, and played a major role in opening the SPECT era of nuclear medicine.

Fig. 1.

GAMMATOM-1 SPECT system, the first nuclear medicine imaging device developed in Korea for tomography (Courtesy of Zang-Hee Cho). The detectors and collimators of GAMMATOM-1 were arranged in a circular arc and a converging hole collimator was used for achieving high spatial resolution

From the early 1980s at SNU, nuclear medicine physics and medical engineering studies, such as the measurement of kidney function using a compartment model and the quantitative evaluation of left and right shunts of the heart using deconvolution analysis, have been conducted through collaboration between the Departments of Nuclear Medicine and Biomedical Engineering [16]. In the early 1980s, scientists at SNU developed a gamma probe-type nuclear stethoscope for the evaluation of the left ventricular function (Fig. 2) [17]. In 1987, Hong Kyu Lee obtained funding amounting to 150 million KRW/year from the Ministry of Science and Technology to undertake SNU’s first large-scale national research project for the development of a bone density meter (dual-photon absorptiometry) using a ¹⁵³Gd radioactive source and an NaI(Tl) scintillation detector.

Fig. 2.

Nuclear stethoscope (Courtesy of Kwang Suk Park)

In 1984, the first medical accelerator in Korea, a 50 MeV cyclotron (MC-50, Scanditronix), was installed at the Korean Cancer Center Hospital (now Korean Institute of Radiological and Medical Sciences, KIRAMS), and used for neutron beam irradiation cancer treatment and the production of radioisotopes for medical use. Since 1990, KIRAMS has produced various medical radioisotopes such as ⁶⁷ Ga, ²⁰¹Tl, and ¹²³I and supplied them to hospitals. In addition, in April 1995, a 300 MW multi-purpose nuclear reactor, ‘Hanaro’, was installed in the Daedeok Research Complex and commenced the production of radioactive isotopes, thereby strengthening Korea’s self-sufficiency in medical radioisotopes.

Progress of Nuclear Medicine Physics Research in the 1990s

In 1994, PET scanners and cyclotrons were installed for the first time in Korea at SNUH and the Samsung Medical Center (SMC). In line with this, research in nuclear medicine physics, devices, and data analysis received an impetus with the appointment of scientists who had majored in medical physics or engineering to major university hospitals. Notable among such appointees are Hee-Joung Kim and Yong Choi, who returned from the United States to join the Seoul Jungang Hospital (now Asan Medical Center) and SMC, respectively, and Cheoleun Kwark, who established a medical physics and engineering research group at SNU.

The Science Research Center (SRC) and Engineering Research Center (ERC) were established at SNU in 1990 and 1994, respectively, with the support of the Korea Science and Engineering Foundation (now National Research Foundation of Korea). With the active involvement of most Korean researchers in nuclear medicine and related areas, these Centers became the cornerstones for establishing nationwide research cooperation in nuclear medicine and molecular imaging. Simultaneously, Korean biomedical engineering benefited enormously from the 7-year-long G7 Leading Technology and Medical Engineering R&D project (1995–2002), which was planned and overseen by Myung-Chul Lee, former President of World Federation of Nuclear Medicine and Biology (WFNMB), at SNU. Under the aegis of this project, Cheoleun Kwark, Hee-Joung Kim, and Yong Choi led the development of multi-purpose mobile gamma probes [18, 19]. This also led to the concomitant development of small gamma cameras for small animals, breasts, and thyroid imaging at the SMC (Fig. 3) [20–22], and digitalization technology for analog gamma cameras at Yonsei University [23]. Based on these technologies, Jong Ho Kim and Soo-Gil So led the commercialization of thyroid probes, automatic gamma counters, and industrial radiation detectors at Seyong Nuclear Development Co. and Woojin Engineering and Technology.

Fig. 3.

Scintimammography system developed by SMC

In the 1990s, the Seoul Jungang Hospital and SNU were the main centers for research on SPECT image analysis. At Seoul Jungang Hospital, Hee-Joung Kim and his trainees, Hye Kyung Son and Jeong-Gyun Bong, conducted extensive research on ¹²³I-IPT and ^99mTc-TRODAT imaging and quantification [24–27]. A brain SPECT image obtained by the Kim group using ^99mTc-TRODAT was selected as the “Image of The Year” by the Society of Nuclear Medicine in 1996 (Fig. 4) [27, 28]. At SNU, Dong Soo Lee established the Diamox SPECT protocol, which deals with the signal-to-noise ratio of the subtraction images [29]. In addition, Kyeong Min Kim and Dong Soo Lee developed a kinetic model for quantifying cerebral blood flow using dynamic ^99mTc-HMPAO [30] as well as a technique for evaluating myocardial contractility using myocardial SPECT and tonometry [31].

Fig. 4.

Quantification of dopamine transporter SPECT images. “Image of the Year” of 1996 Annual Meeting of Society of Nuclear Medicine. (Reprint from [28] with permission; © 1996 SNMMI)

Tracer Kinetic Modeling and Brain Image Analysis

Exploiting the use of PET scanners in conjunction with cyclotrons, researchers at SNU and SMC carried out extensive studies on the quantification of myocardial blood flow using ¹⁵O-water and ¹³ N-ammonia, respectively [32–40]. Studies by SNU scientists in the early 2000s on the automatic extraction of the left ventricular input function using multivariate analysis techniques [32–34, 36] and the generation of parametric images of myocardial blood flow based on multiple linear analysis [35, 37] received significant attention from the academic community. Noteworthy among these is Jae Sung Lee’s 2001 study [36], which is acknowledged as the first to apply the independent component analysis technique to nuclear medical imaging (Fig. 5). Dong Soo Lee’s project aimed at the quantification of myocardial blood flow using ¹⁵O-water PET won recognition as one of the 50 Best Research Projects in 2005 by the Korea Science and Engineering Foundation. Research on tracer kinetic analysis expanded further as Kyeong Min Kim and Jae Sung Lee returned to Korea after their post-doc training and were appointed to KIRAMS and SNU, respectively [41–47]. SNU group evaluated the dopamine D2 receptor occupancy of YKP-1358, a new drug candidate for schizophrenia developed by SK Corporation, which helped the drug obtain approval from the US FDA in 2010 [48]. This provided a stimulus to the active utilization of PET scans for new drug development and pharmacokinetic research in Korea. In 2008, Su Jin Kim and Jae Sung Lee at SNU developed a new linear analysis for the quantification of tracers with irreversible binding, which was featured as a cover paper by the Journal of Cerebral Blood Flow & Metabolism [41]. Further, Seongho Seo developed a bi-graphical analysis for the quantification of ¹⁸F-FP-CIT, which is widely used in Korea (Fig. 6) [42].

Fig. 5.

Independent component analysis for PET images of (A) heart and (B) brain (Reprint from [36, 64] with permission and according to the publisher’s open access policy; © 2001 SNMMI and 2003 John Wiley & Sons)

Fig. 6.

Tracer kinetic modeling for (A) irreversible and (B) slowly reversible tracers. New linear analysis methods in right column (MLAIR2 and noninvasive RE-GP) outperformed conventional approaches in left (Reprint from [41, 42] with permission; © 2008 ICBFM and 2016 IPEM)

The research on brain PET and SPECT image analysis that has been actively pursued at SNU since the mid-1990s has contributed significantly to the advancement of nuclear neuroimaging and functional brain mapping in Korea [49–54]. Dong Soo Lee and Jae Sung Lee developed standard Korean brain templates and population-based probabilistic maps and made them available nationwide along with brain image quantification tools based on them [55–61]. Automatic brain PET interpretation using artificial neural networks, brain image registration and fusion technique development, and functional brain PET analysis using independent component analysis are other important achievements of researchers at SNU [62–64]. The outstanding contributions of Hae-Jeong Park of the Department of Nuclear Medicine at Yonsei University and Jungsu Oh of the Asan Medical Center in the field of diffusion tensor MRI [65, 66] have also led to significant advancements in MRI-based brain PET image analysis technology [64, 67–70].

Kyeong Min Kim, who, as an associate of Prof. Dong Soo Lee, laid the foundation for nuclear medicine physics research at SNU in the mid-late 1990s, initiated physics research at the Nuclear Medicine and RI Research Department (now Molecular Imaging Research Center) of KIRAMS in 2005. Subsequently, Sang-Keun Woo, Jin Su Kim, Jong Guk Kim, and Ji-Ae Park and graduate students from Yonsei and Korea Universities joined to establish a physics research group at KIRAMS; this group has undertaken extensive research on small-animal PET imaging and internal radiation dosimetry [71–74].

Medical Cyclotrons

As mentioned above, an EBCO 13 MeV cyclotron was installed at SNUH in 1994. At the same time, a GE PET Tracer was installed at the SMC. KIRAMS installed a high current 30 MeV cyclotron (IBA Cyclone-30) to increase the availability of accelerator radiopharmaceuticals in Korea and began mass production of radioisotopes in October 2004. This led to a remarkable increase in the production of ²⁰¹Tl and ¹²³I.

Dr. Jong Seo Chai’s group at KIRAMS started the indigenous development of medical cyclotrons in 1998 and succeeded in beam extraction experiments and production of radioactive isotopes from the first domestic cyclotron, KIRAMS-13, in 2005 (Fig. 7). The KIRAMS-13 systems were provided to six universities and university hospitals through the support of the Ministry of Science and Technology, enabling nationwide supply of radiopharmaceuticals for PET. The technology for the manufacture of the KIRAMS-13 cyclotron was subsequently transferred to Samyoung Unitech.

Fig. 7.

KIRAMS-13 cyclotron (Courtesy of Jong Seo Chai)

Imaging Instrumentation

In 1999, a mid-to-long term nuclear energy project, “Development of Nuclear Medical Instruments and Basic Study,” was initiated at KAIST with Gyuseong Cho as the principal investigator to develop a gamma camera system and related algorithms and software. This large-scale pan-Korean project involved the participation of most domestic nuclear medical physics researchers based in SNU, Yonsei University, Catholic University, Korean Cancer Center, Ajou University, SMC, and other organizations (Fig. 8A). Although the project was not ultimately successful in producing a gamma camera design that could be commercialized, it became a model for subsequent large-scale projects for the development of nuclear medical imaging devices in Korea. In addition, it led to the establishment of substantial research infrastructure and provided an opportunity to cultivate a large number of excellent researchers. In 2002, a follow-up mid-to-long term nuclear energy project, “Development of Nuclear Medicine Instrumentation Core Technology,” commenced with Yong Choi at SMC as the principal investigator, and involving researchers at the Seyong Nuclear Development Co. and Inje University as collaborators. This project led to the development of Korea's first small-animal PET and SPECT systems (Fig. 9) and initiated the development of a larger SPECT system (Fig. 8B) [75–78].

Fig. 8.

A Gamma camera and(B) SPECT system developed under the aegis of mid-to-long term nuclear energy projects (Courtesy of Yong Hyun Chung and Jong Ho Kim)

Fig. 9.

Small-animal SPECT (left) and PET (right) systems developed under the aegis of the mid-to-long term nuclear energy projects

As molecular imaging received considerable research attention and small animal imaging became the focus of increased interest in the 2000s, small-animal PET systems were set up in many institutions [79, 80]. Moreover, SMC and SNU undertook the in-house development of small animal PET systems. Yong Choi's group at SMC developed Korea’s first small animal PET in 2005, with support from the mid-to-long term nuclear energy project as well as international collaborative research programs, such as Crystal Clear Collaboration and OpenGATE Collaboration (Fig. 9). Jae Sung Lee's lab at SNU developed several PET detectors capable of measuring the depth-of-interaction (DOI), in collaboration with Seong Jong Hong of the Department of Physics at Korea University (Fig. 10A–C) [81–83]. They also developed a small animal PET system using multi-anode photomultiplier tubes (PMTs) with a wide effective area [84], and extrapolated this design to develop a breast PET scanner (Fig. 11) [85]. Around this time, substantial efforts were devoted, in Korea as well as worldwide, to the development of DOI PET detectors to increase the uniformity of PET spatial resolution [86]. Significant among these endeavors are a DOI PET detector that uses a quasi-monolithic scintillation crystal (Fig. 10C) developed by Yong Hyun Chung’s group in the Department of Radiological Science at Yonsei University [87, 88] and the continuous DOI measurement technology using triangular reflectors (Fig. 10D) developed by researchers at SNU [82, 89–91].

Fig. 10.

Depth-of-interaction (DOI) PET detectors. (A) 3-layer DOI detector using 2 different types of crystals. (B) 4-layer DOI detector using single type of crystal. (C) Continuous DOI measurement using light dispersion control.(D) Quasi-monolithic DOI detector (Reprint from [81–83, 86, 87, 89] with permission; © 2008 and 2010 IEEE, 2010 and 2013 IPEM, 2011 KOSOMBE and Springer, and 2010 Elsevier)

Fig. 11.

Small-animal (left) and breast PET (right) systems using flat-panel multi-anode PMTs developed by SNU

In the mid-2000s, Chun Sik Lee of the Department of Physics at Chung-Ang University, in collaboration with scientists at SNU, Hanyang University, and Paichai University, undertook a project funded by the Basic Atomic Energy Research Institute for the development of Compton cameras that might be useful for nuclear medicine. Once again, although the project was not successful in realizing a Compton camera system capable of obtaining biomedical images, it was marked by multiple achievements of note, such as the first report of ordered subset expectation maximization and point spread function reconstruction algorithms for Compton cameras [92–95]. Chan-Hyeong Kim’s group at Hanyang University has continued to develop various types of Compton cameras for monitoring nuclear materials and environmental radiation measurements.

Meanwhile, in 2007, Jinhun Joung, formerly of Siemens Medical, established NuCare, Inc. for developing commercial nuclear medicine devices and radiation measurement systems. NuCare has commercialized a thyroid probe and a mobile gamma camera (Fig. 12); however, in recent years, the company has shifted its focus to the radiation inspection and monitoring equipment market to capitalize on the rapidly growing demand for radionuclide analyzers following the Fukushima nuclear power plant accident in 2011.

Fig. 12.

NuCare’s thyroid probe and a mobile gamma camera (courtesy of NuCare, Inc.)

Hybrid Imaging Systems

In 2004, Zang-Hee Cho at Gachon Medical School commenced the development of a PET/MRI using a 7 T MRI and Siemens’s HRRT PET for brain imaging [11–13]. KIRAMS and Yonsei University attempted the development of a whole-body PET/MRI that combines PET/CT and 3 T MRI. In these systems, PMT-based PET and high-field MRI were installed in separate rooms and a shuttle bed was used to move patients between the scanners. Although the clinical usefulness of these systems has not been established, they drew interest from other Korean researchers working in the area of PET and MRI.

Researchers in Korea were cognizant of the potential of silicon photomultipliers (SiPMs) to replace PMT and avalanche photodiode sensors, and took an early interest in the development of SiPM-based PET and simultaneous PET/MRI [96–102]. In fact, researchers at SNU discontinued their endeavors for the further development of their breast PET scanner based on a multi-anode PMT, shifted their focus to the development of SiPM PET, and successfully demonstrated the potential of an SiPM-based scintillation detector for use in combined PET/MRI in 2008 [101]. They also presented the world’s first SiPM PET image at the annual meeting of Society of Nuclear Medicine in June 2009 (Fig. 13A) [98, 103], and PET/MR images of living animals acquired using SiPM PET and 3 T MRI at the 2011 meeting (Fig. 13B) [104, 105]. A project to develop brain PET/MRI technology and related components with Gyuseong Cho at KAIST as the principal investigator and involving collaborations with researchers based in Sogang University, SNU, Kyungpook National University, and KIRAMS commenced in 2007, with funding from the Ministry of Commerce, Industry and Energy. The development of an SiPM sensors suitable for PET imaging by KAIST and the National NanoFab Center [106, 107], and the first demonstration in the world of the combination of an SiPM-based brain PET system with 3 T MRI by Sogang University and KAIST were among the successful outcomes of this project (Fig. 14) [108–110]. Jin Ho Jung, Key Jo Hong, Jiwoong Jung, and Jihoon Kang made key contributions to the PET/MRI technology development at Sogang University. In recognition of their notable contributions to the area of PET/MRI, Prof. Jae Sung Lee of SNU was chosen as one of the “Top 100 Future Technologies and Leaders in 2020” by the National Academy of Engineering of Korea in 2013, and Prof. Yong Choi of Sogang University was awarded a Ministerial Award from the Minister of Trade, Industry and Energy in 2014.

Fig. 13.

SiPM-based small animal (A) PET and (B) MRI-compatible PET insert developed by SNU (Reprint from [98, 105] with permission; © 2011 and 2012 SNMMI)

Fig. 14.

Brain PET insert for 3 T MRI developed by Sogang University and KAIST (Reprint from [108] with permission; ©2013 AAPM)

Recent Advances

The late 2010s saw considerable activity in the area of PET systems research. SNU and Sogang University developed SiPM PET inserts combined with small-animal ultra-high-field MRI systems (Fig. 15) [111–113]. Gachon University researchers, in collaboration with scientists at Sogang University and KAIST, developed brain-body convertible PET scanner (Fig. 16) [114]. Researchers at SNU developed a whole-body time-of-flight PET with a time resolution of 360 ps using high-quantum-efficiency multi-anode PMTs [115], a brain PET scanner based on a new comparator-less PET data acquisition system [116], and an SiPM-based brain PET insert for 7 T PET/MRI imaging (Fig. 17) [117]. SNU’s brain PET insert was the first PET system in Korea that allowed the scan of the entire human brain in a single-bed position. Scientists at Sogang University also developed a time-of-flight PET system, which is based on a capacitive multiplexing readout of SiPM signals [118]. Prof. Seong Jong Hong of Eulji University led the development of a MR-compatible SiPM PET with short optical fiber bundles [119] and a multimodal laparoscopic system that allows simultaneous visible, near-infrared, and gamma-ray imaging for minimally invasive surgery [120–122] (Fig. 18) [120–122]. Prof. Jungyeol Yeom of Korea University reported interesting results on new fast scintillators in collaboration with Japanese scientists [123, 124], and led the development of DOI detectors based on the wavelength discrimination technique [125, 126]. Also in Korea University, Prof. Kisung Lee’s group developed a SPECT system using a variable pinhole collimator composed of multiple tungsten layers (Fig. 19) [127–129]. Prof. Jungsu Oh at the Asan Medical Center, University of Ulsan developed various image processing techniques for PET image analysis [70, 130, 131].

Fig. 15.

PET inserts for small animal dedicated ultra-high-field MRI, developed by (A) SNU and (B) Sogang University (Reprint from [112, 113] with permission; © 2016 AAPM and 2019 IPEM)

Fig. 16.

Zoom PET developed jointly by scientists at Gachon University, Sogang University, and KAIST (Reprint from [114]; © 2019 IEEE)

Fig. 17.

A TOF PET based on high-quantum-efficiency multi-anode PMT and (B) brain PET insert for 7 T MRI developed by SNU (Reprint from [115, 117] with permission and according to the publisher’s open access policy; © 2017 AAPM and 2021 IEEE).

Fig. 18.

Multimodal laparoscope for simultaneous NIR/gamma/visible imaging developed by Eulji University (Reprint from [122] with permission; © 2018 OSA)

Fig. 19.

SPECT with a variable pinhole collimator composed of multiple tungsten layers developed by Korea University (Reprint from [129] with permission; © 2021 Elsevier)

In recent years, Korean scientists involved in PET system R&D have successfully commercialized their inventions made over the last two decades. In 2016, Prof. Jae Sung Lee and his trainees, Guen Bae Ko and Kyeong Yun Kim, founded Brightonix Imaging Inc., and Jeong-Whan Son, Seung Kwan Kang, and Seong A Shin joined the company, producing PET inserts for small animal PET/MRI and developing clinical PET systems (Fig. 20) [132, 133]. Promising results are being achieved by providing PET/MRI systems to molecular imaging centers around the world, in partnership with Aspect Imaging in Israel. In order to strengthen the competitiveness of the medical device industry in Korea, the Ministry of Science and ICT, the Ministry of Trade, Industry and Energy, the Ministry of Health and Welfare, and the Ministry of Food and Drug Safety have jointly invested 1.2 trillion KRW for 6-year from 2020 (Korea Medical Device Development Fund). The fund currently supports many R&D activities in the field of medical imaging, notable among which are projects for the development of a brain PET scanner for identifying degenerative brain diseases led by Brightonix Imaging, Inc., and a multimodal optical imaging system for image-guided minimally invasive surgery at the National Cancer Center.

Fig. 20.

Brightonix Imaging’s SimPET for simultaneous PET/MRI (Reprint from [132, 133] with permission; © 2020 and 2021 WMIS)

With the use of PET/MRI systems for clinical purposes, the limitations of MRI-based PET attenuation correction have come to be highlighted [134–136]. In view of this, SNU proposed a new UTE MRI segmentation method using a multiphase level-set algorithm [137], and significantly improved the result of simultaneously reconstructed activity and attenuation maps using deep learning (Fig. 21) [138–141]. According to the increasing use of targeted radionuclide therapy and the development of new radiotracers, research activity on image-based dosimetry has increased remarkably [142–153]. In particular, new methods to replace the Monte Carlo simulation technique are attracting attention [148, 150].

Fig. 21.

Deep learning for PET attenuation correction (Reprint from [139] with permission; © 2018 SNMMI)

The defeat of Lee Se-dol by the computer program, AlphaGo in the 2016 Google Deep Mind Challenge match of the board game Go drew the attention of scientists and researchers across disciplines worldwide to the potential of artificial intelligence (AI) and deep learning (DL). These technologies have since had a revolutionary impact on the field of medical image processing. Korean researchers have played a leading role in applying the DL concept to medical image processing, authoring two of the first three DL papers published in the Journal of Nuclear Medicine [139, 154]. Currently, Korean researchers are actively involved in endeavors to solve a variety of complex problems in nuclear medicine physics and engineering, such as amyloid PET spatial normalization, fast voxel-based dosimetry, simultaneous activity and attenuation reconstruction, and scan time reduction, using AI and DL technologies [138–141, 150, 155–162]. Deep learning-based brain PET and SPECT image analysis is another important focus area among Korean researchers [131, 163–170]. A study on the prediction of cognitive decline in the patients with mild cognitive impairment by Prof. Hongyoon Choi at SNUH, which was featured in the MIT review, is a noteworthy example of Korean research in this area (Fig. 22) [168].

Fig. 22.

Predicting cognitive decline using deep learning technology (Reprint from [168] with permission;

Korean Council of Nuclear Medicine Imaging and Instrumentation and IEEE NPSS Seoul Chapter

In the 2000s, as there were sizeable cohorts of doctoral students in nuclear medicine physics graduated from SNU, Yonsei University, and SMC, the need for regular academic conferences and social gatherings was felt. Therefore, in January 2005, Keon Wook Kang, Jong Ho Kim, Jae Sung Lee, and Yong Choi held a meeting at SNUH to prepare the ground for the Korean Council of Nuclear Medicine Imaging and Instrumentation (NMI²), and drew up a plan for the organization and activities of the council. The plan was approved by the Korean Society of Nuclear Medicine in the fall of 2005. On February 27, 2006, the inaugural meeting of NMI² was held at the Paichai Jeong-dong Building. Thereafter, the council was also registered with the Korean Society of Medical Physics. After June-Key Chung and Hee-Joung Kim served as the first and second chairmen, respectively, members with MD and PhD degrees have taken on the role of NMI² chairman by rotation. Every winter, NMI² holds a joint symposium with the IEEE NPSS Seoul Chapter and the Korean Society for Radiation Industry.

NMI² has also led to the establishment of the Nuclear and Plasma Sciences Society (NPSS) Chapter of the Institute of Electrical and Electronics Engineers (IEEE), Seoul Section. The IEEE Nuclear Science Symposium & Medical Imaging Conference (NSS/MIC) is the largest international conference of the IEEE NPSS, and is the conference of choice for Korean researchers in the area of radiation and nuclear medicine physics and devices. This conference has traditionally been held only in the United States. However, as the international membership of the NPSS has grown, venues outside the US have been chosen for the conference. In December 2006, Hee-Joung Kim, Gyuseong Cho, and Jae Sung Lee organized a hosting committee to submit proposals for organizing the NSS/MIC conference in Korea and initiated the foundation of NPSS Chapter of Seoul Section (NPSS Seoul Chapter). The inaugural meeting of NPSS Seoul Chapter was held at COEX on July 30, 2009. Thanks to the joint efforts of Korean researchers in the fields of radiation and nuclear science, the NPSS Seoul Chapter successfully hosted the IEEE NSS/MIC meeting in Seoul in 2013. For the 2013 NSS/MIC, Hee-Joung Kim, Gyuseong Cho, Jae Sung Lee, and Jang Ho Ha served as the General, NSS, MIC, and RTSD chairs, respectively, and many Korean researchers served as members of the organizing committee. The theme of the meeting was “Beyond Imagination of Future Science”. The 2013 NSS/MIC, which was held at COEX in Seoul, with the largest participation ever (2,400 people from 50 countries), is regarded by many as one of the most successful NSS/MICs (Fig. 23).

Fig. 23.

General Chair’s reception at the 2013 IEEE NSS/MIC

Declarations

Ethics Approval

For this type of study, ethical approval is not required.

Informed Consent

For this type of study, informed consent is not required.

Conflict of Interest

Jae Sung Lee, Kyeong Min Kim, Yong Choi, and Hee-Joung Kim declare that they have no conflict of interest.