• The Korean Journal of Nuclear Medicine Technology
• /
• v.28 no.1
• /
• pp.1-11
• /
• 2024

Hypoxia, defined as the deficiency of oxygen, is a significant hallmark of cancers presenting in the majority of solid tumors. Detection of tumor hypoxia is essential in cancer diagnosis to prevent cancer progression, metastasis, and resistance to cancer therapies in clinical practices. Single-photon emission computed tomography (SPECT) is one of the methods studied and applied for hypoxia detection with the use of radiolabeled imaging agents in which ^99mTc is the common radioisotope used for radiolabeling. Nitroimidazoles are the hypoxia-targeting moieties presenting in numerous ^99mTc-radiolabeled imaging agents due to their bio-reducible ability in hypoxic environments. Recently, in addition to ^99mTc-labeled radiopharmaceuticals containing one nitroimidazole unit, there has been considerable attention given to ^99mTc-radiopharmaceuticals bearing two or more nitroimidazole units. This review summarizes the synthesis of hypoxia-targeting chelators and radiolabeling processes to produce these ^99mTc-radiopharmaceuticals for SPECT imaging.

• 대한두경부종양학회:학술대회논문집
• /
• 2009.11a
• /
• pp.185-185
• /
• 2009

• 대한핵의학회:학술대회논문집
• /
• 1996.10a
• /
• pp.426-426
• /
• 1996

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.11
• /
• pp.4487-4491
• /
• 2014

Objective: To explore the clinical manifestations and imaging characteristics of gliomatosis cerebri to raise the awareness and improve its diagnostic accuracy for patients. Materials and Methods: Clinical data, imaging characteristics and pathological examination of 12 patients with GC from Jan., 2008 to Jan., 2012 were analyzed retrospectively. Results: Patients with GC were clinically manifested with headache, vomiting, repeated seizures, fatigue and unstable walking, most of whom had more than 2 lesions involving in parietal lobe, followed by temporal lobe, frontal lobe, periventricular white matter and corpus callosum. Magnetic resonance imaging (MRI) showed diffuse distribution, T1-weighted images (T1WI) with equal and low signals and T2-weighted images (T2WI) with bilateral symmetrical high diffuse signals. There was no reinforcement by enhancement scanning and signals were different in diffusion-weighted images (DWI). The higher the tumor staging, the stronger the signals. Pathological examination showed neuroastrocytoma in which tumor tissues were manifested by infiltrative growth in blood vessels and around neurons. Conclusions: In clinical diagnosis of GC, much attention should be paid to the diffuse distribution of imaging characteristics, incomplete matching between clinical and imaging characteristics and confirmation by combining with histopathological examination.

• Journal of Biomedical Engineering Research
• /
• v.28 no.4
• /
• pp.471-476
• /
• 2007

Various active microwave imaging techniques have been developed for cancer detection for past several decades. Both the microwave tomography and the UWB radar techniques, constituting functional microwave imaging systems, use the electrical property contrast between normal tissues and malignancies to detect the latter in an early development stage. Even though promising simulation results have been reported, the understanding of the functional microwave imaging diagnostics has been relied heavily on the complicated numerical results. We present a computationally efficient and physically instructive analytical electromagnetic wave channel models developed for functional microwave imaging system in order to detect especially the breast tumors as early as possible. The channel model covers the propagation factors that have been examined in the previous 2-D models, such as the radial spreading, path loss, partial reflection and transmission of the backscattered electromagnetic waves from the tumor cell. The effects of the system noise and the noise from the inhomogeneity of the tissue to the reconstruction algorithm are modeled as well. The characteristics of the reconstructed images of the tumor using the proposed model are compared with those from the confocal microwave imaging.

• Journal of Biomedical Engineering Research
• /
• v.33 no.3
• /
• pp.105-113
• /
• 2012

Biopsy is a type of histopathological examinations, in which a physician samples cells or tissues from a patient's suspicious lesion. Such a lesion frequently resides deep inside human body, and then a percutaneous biopsy is therefore performed using a thick needle with the assistance of medical imaging such as computed tomography(CT) and magnetic resonance imaging(MRI). Recently modern robotic technology is being introduced to percutaneous biopsy in order to reduce any possible human error and hazard on physicians caused by medical imaging. After medical imaging locates the exact location of lesion, an optimization algorithm plans the path for a biopsy needle. Subsequently, a robot system moves the biopsy needle to the lesion in accurate and safe way with the control of a practitioner or automatically. In this article, we try to look into the state-of-art of percutaneous biopsy using such robotic technology. We classified percutaneous biopsy robots by mechanical characteristics and by imaging technology. Then, advantage and disadvantage of each class type are described as well as the basic description, and a few representative designs for each type are introduced. Current research issues of robotized percutaneous biopsy are subjectively selected for the readers' convenience. We emphasize the basic technology of actuator and sensors compatible with imaging technology to conclude this review.

• Korean Journal of Bronchoesophagology
• /
• v.4 no.1
• /
• pp.43-51
• /
• 1998

Background： Three-dementional imaging with spiral CT(3D spiral CT) is a well established imaging modality which has been investigated in various clinical settings. However the 3D spiral CT in upper airway disease is rarely reported and its results are still obscure. Objectives： To access the usefulness of 3D spiral CT imaging in patients with upper airway diseases. Materials and Methods We performed 3D spiral CT in fourteen patients In whom upper airway diseases were clinically suspected. Nine of these patients had upper airway stenosis, two had laryngeal cartilage fracture, and three had laryngo-hypopharyngeal cancer. For evaluation of location and extent of the lesions, we compared the findings of 3D imaging with those of air tracheogram, conventional 2D CT images, endoscopic and operative findings. Results： In case of stenosis, 3D spiral CT provide significant useful information, particularly the site and length of the stenotic segment. But, it was difficult to define the fracture of the laryngeal framework and to detect the cartilagenous invasion by head and neck cancer using the 3D imaging. Conclusion : The 3D spiral CT was an useful adjunctive method to assess some kind of upper airway disease but not in others. So, we should compare the findings of 3D images with those of other diagnostic tools for accurate diagnosis of the upper airway disease.

• Journal of Gastric Cancer
• /
• v.12 no.1
• /
• pp.7-12
• /
• 2012

More than ten years have passed since the sentinel node (SN) concept for gastric cancer surgery was first discussed. Less invasive modified surgical approaches based on the SN concept have already been put into practice for malignant melanoma and breast cancer, however the SN concept is not yet placed in a standard position in gastric cancer surgery even after two multi-institutional prospective clinical trials, the Japan Clinical Oncology Group trial (JCOG0302) and the Japanese Society for Sentinel Node Navigation Surgery (SNNS) trial. What is the problem in the clinical application of the SN concept to gastric cancer surgery? There is no doubt that we need reliable indicator(s) to determine with certainty the absence of metastasis in the lymph nodes in order to avoid unnecessary lymphadenectomy. There are several matters of debate in performing the actual procedure, such as the type of tracer, the site of injection, how to detect and harvest, how to detect metastases of SNs, and learning period. These issues have to be addressed further to establish the most suitable procedure. Novel technologies such as indocyanine green (ICG) fluorescence imaging and one-step nucleic acid amplification (OSNA) may overcome the current difficulties. Once we know what the problems are and how to tackle them, we can pursue the goal.

• Nuclear Medicine and Molecular Imaging
• /
• v.42 no.sup1
• /
• pp.91-100
• /
• 2008

Ovarian cancer is often fatal since it is difficult to diagnose early and recurrence is quite frequent despite successful implementation of cytoreductive surgery and chemotherapy, thus exact diagnosis and early detection of recurrence are crucial to patient management. For pre-treatment staging, FDG PET could be helpful in a limited patient group possessing high risks of ovarian cancer. Besides, FDG PET could be recommended to patients with a high suspicion of recurrence i.e. rise of CA-125, especially in cases of conventional diagnostic imaging modalities presenting no evidence of disease because FDG PET provides critical information for treatment planning such as recurrence site or pattern. In order to expand the use of FDG PET to general population at staging or routine surveillance of ovarian cancer, more investigation is needed. The usefulness of FDG PET in evaluating treatment response and prognosis of ovarian cancer has not yet been determined, but it has been reported that FDG PET could evaluate treatment response early and show a close relationship with overall survival. PET/CT has been actively adopted in management of ovarian cancer. Not only in detecting tumor recurrence and evaluating treatment response but also in pre-treatment staging, FDG PET/CT is expected to playa role due to available anatomical information.

• Journal of Korea Multimedia Society
• /
• v.18 no.12
• /
• pp.1445-1452
• /
• 2015

In these days, fluorescent materials such as ICG or 5-ALA is used for the brain surgery. The patients who underwent brain tumor surgery has been increased during last 30 years and the survivorship rate increased 22∼33% in 5 years. Recently, the Fluorescence induction surgery is developed for more safety and improved the resection rate for the glioma in the neurosurgery field. In this study, we proposed fluorescence area detection method for ICG and 5-ALA fluorescence induced surgery using acquired images from image processing. Accuracy was 99.21% from ICG images, and 99.51% from 5-ALA images. Matthews correlation coefficient was 88.67% from ICG images, and 90.49% from 5-ALA images.