• Title/Summary/Keyword: Localization Imaging

Search Result 190, Processing Time 0.022 seconds

Quantitative Assessment of Cerebral Perfusion Reserves Using Normalized Difference Ratio Image of Brain SPECT (뇌혈류 SPECT에서 정규화감산영상을 이용한 뇌혈류비축능의 정량적 평가에 관한 연구)

  • Lee, J.S.;Kwark, C.;Park, K.S.;Jeong, J.M.;Lee, D.S.;Chung, J.K.;Lee, M.C.;Koh, C.S.
    • Proceedings of the KOSOMBE Conference
    • /
    • v.1996 no.05
    • /
    • pp.279-282
    • /
    • 1996
  • Sequential brain SPECT imaging has been used to assess the cerebral perfusion reserve(CPR) in cerebrovascular diseases(CVD). We have realized a parametric images of CPR using normalized difference ratio and deadtime correction. For the anatomical localization of CPR, the parametric images were registered to the contours of the cerebral regions using optimal threshold method. The parametric imags reflected the CPR more reliably and distinctively. We conclude that the qunatitative estimation of CPR using normalized difference ratio image could be useful for the diagnosis and assessment of postoperative prognosis in CVD.

  • PDF

Characterization of the Spatial Variability of Paper Formation Using a Continuous Wavelet Transform

  • Keller, D.Steven;Luner, Philip;Pawlak, Joel J.
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.32 no.5
    • /
    • pp.14-25
    • /
    • 2000
  • In this investigation, a wavelet transform analysis was used to decompose beta-radiographic formation images into spectral and spatial components. Conventional formation analysis may use spectral analysis, based on Fourier transformation or variance vs. zone size, to describe the grammage distribution of features such as flocs, streaks and mean fiber orientation. However, these methods have limited utility for the analysis of statistically stationary data sets where variance is not uniform with position, e.g. paper machine CD profiles (especially those that contain streaks). A continuous wavelet transform was used to analyze formation data arrays obtained from radiographic imaging of handsheets and cross machine paper samples. The response of the analytical method to grammage, floc size distribution, mean fiber orientation an sensitivity to feature localization were assessed. From wavelet analysis, the change in scale of grammage variation as a function of position was used to demonstrate regular and isolated differences in the formed structure.

  • PDF

Therapeutic radionuclides (치료용 방사성동위원소)

  • Choi, Sun-Ju;Hong, Young-Don;Lee, So-Young
    • Nuclear Medicine and Molecular Imaging
    • /
    • v.40 no.2
    • /
    • pp.58-65
    • /
    • 2006
  • Since the development of sophisticated molecular carriers such as octereotides for peptide receptor targeting and monoclonal antibodies against various antigens associated with specific tumor types, radionuclide therapy (RNT) employing open sources of therapeutic agents is promising modality for treatment of tumors. furthermore, the emerging of new therapeutic regimes and new approaches for tumor treatment using radionuclide are anticipated in near future. In targeted radiotherapy using peptides and other receptor based tarrier molecules, the use of radionuclide with high specific activity in formulating the radiopharmaceutical is essential in order to deliver sufficient number of radionuclides to the target site without saturating the target. In order to develop effective radiopharmaceuticals for therapeutic applications, it is crucial to carefully consider the choice of appropriate radionuclides as well as the tarrier moiety with suitable pharmacokinetic properties that could result in good in vivo localization and desired excretion. Up to date, only a limited number of radionuclides have been applied in radiopharmaceutical development due to the constraints in compliance with their physical half-life, decay characteristics, cost and availability in therapeutic applications. In this review article, we intend to provide with the improved understanding of the factors of importance of appropriate radionuclide for therapy with respect to their physical properties and therapeutic applications.

Review of Radionuclide Treatment for Neuroendocrine Tumors (신경내분비종양의 방사성핵종 치료)

  • Jeong, Hwan-Jeong
    • Nuclear Medicine and Molecular Imaging
    • /
    • v.40 no.2
    • /
    • pp.90-95
    • /
    • 2006
  • Neuroendocrine tumors (NETs) consist of a heterogeneous group of tumors that are able to uptake neuroamine and/or specific receptors, such as somatostatin receptors, which can play important roles of the localization and treatment of these tumors. When considering therapy with radionuclides, the best radioligand should be carefully investigated. $^{131}I$-MIBG and beta-particle emitter labeled somatostatin analogs are well established radionuclide therapy modalities for NETs. $^{111}In,\;^{90}Y\;and\;^{177}Lu$ radiolabeled somatostatin analogues have been used for treatment of NETs. Further, radionuclide therapy modalities, for example, radioimmunotherapy, radiolabeled peptides such as minigastrin are currently under development and in different phases of clinical investigation. for all radionuclides used for therapy, long-term and survival statistics are not yet available and only partial tumour responses have been obtained using $^{131}I$-MIBG and $^{111}In$-octreotide. Experimental results using $^{90}Y$-DOTA-lanreotide as well as $^{90}Y-DOTA-D-Phe1-Tyr^3-octreotide$ and/or $^{177}Lu-DOTA-Tyr^3-octreotate$ have indicated the possible clinical potential of radionuclides receptor-targeted radiotherapy it may be hoped that the efficacy of radionuclide therapy will be improved by co-administration of chemotherapeutic drugs whose antitumoral properties may be synergistic with that of irradiation.

Region of Interest Localization for Bone Age Estimation Using Whole-Body Bone Scintigraphy

  • Do, Thanh-Cong;Yang, Hyung Jeong;Kim, Soo Hyung;Lee, Guee Sang;Kang, Sae Ryung;Min, Jung Joon
    • Smart Media Journal
    • /
    • v.10 no.2
    • /
    • pp.22-29
    • /
    • 2021
  • In the past decade, deep learning has been applied to various medical image analysis tasks. Skeletal bone age estimation is clinically important as it can help prevent age-related illness and pave the way for new anti-aging therapies. Recent research has applied deep learning techniques to the task of bone age assessment and achieved positive results. In this paper, we propose a bone age prediction method using a deep convolutional neural network. Specifically, we first train a classification model that automatically localizes the most discriminative region of an image and crops it from the original image. The regions of interest are then used as input for a regression model to estimate the age of the patient. The experiments are conducted on a whole-body scintigraphy dataset that was collected by Chonnam National University Hwasun Hospital. The experimental results illustrate the potential of our proposed method, which has a mean absolute error of 3.35 years. Our proposed framework can be used as a robust supporting tool for clinicians to prevent age-related diseases.

Ophthalmic Manifestations of Cavernous Sinus Syndrome in a Yorkshire Terrier Dog

  • Sehan Shin;Sol Kim;Seonmi Kang;Jihye Choi;Kangmoon Seo
    • Journal of Veterinary Clinics
    • /
    • v.40 no.5
    • /
    • pp.360-364
    • /
    • 2023
  • A 7-year-old castrated male Yorkshire Terrier presented for a palpable mass of the right neck with ophthalmic signs of conjunctival hyperemia and anisocoria with fixed mydriatic pupil of the right eye. Clinical examination findings included the absence of direct and consensual pupillary light reflexes, external and internal ophthalmoplegia, and corneal hypoesthesia with incomplete blinking of the right eye. Magnetic resonance imaging and computed tomography revealed a mass extending from the right cavernous sinus to the orbital fissure with neighboring bone lysis. Cytological examination of fine-needle aspiration samples of the mass revealed a neuroendocrine tumor. The owner declined further diagnosis and did not wish to care for the dog receiving chemotherapy. This study describes the importance of investigating neuro-ophthalmic findings, which might provide clues for the localization of lesions, including tumors, to aid in diagnosis.

Diagnosis of Recurrent Uterine Cervical Cancer: Computed Tomography versus Positron Emission Tomography

  • Dong Hee Park;Kie Hwan Kim;Sang Yoon Park;Byung Hee Lee;Chang Woon Choi;Soo Yil Chin
    • Korean Journal of Radiology
    • /
    • v.1 no.1
    • /
    • pp.51-55
    • /
    • 2000
  • Objective: To determine the accuracy of CT and positron emission tomography (PET) in the diagnosis of recurrent uterine cervical cancer. Materials and Methods: Imaging findings of CT and PET in 36 patients (mean age, 53 years) in whom recurrent uterine cervical cancer was suspected were analyzed retrospectively. Between October 1997 and May 1998, they had undergone surgery and/or radiation therapy. Tumor recurrence was confirmed by pathologic examination or follow-up studies. Results: In detecting recurrent uterine cervical cancer, the sensitivity, specificity, and accuracy of CT were 77.8%, 83.3%, and 80.5%, respectively, while for PET, the corresponding figures were 100%, 94.4%, and 97.2%. The Chi-square test revealed no significant difference in specificity (p = .2888), but significant differences in sensitivity (p = .0339) and accuracy (p = .0244). Conclusion: PET proved to be a reliable screening method for detecting recurrent uterine cervical cancer, but to determine the anatomical localization of recurrent tumors, and thus decide an adequate treatment plan, CT was eventually needed.

  • PDF

A Potential New Mouse Model of Axial Spondyloarthritis Involving the Complement System

  • V. Michael Holers;Francisco G. La Rosa;Nirmal K. Banda
    • IMMUNE NETWORK
    • /
    • v.21 no.6
    • /
    • pp.45.1-45.13
    • /
    • 2021
  • Many mouse models of rheumatoid arthritis have been identified, but only a limited number are present for axial spondyloarthritis (AxSpA). Collagen Ab-induced arthritis (CAIA) is one of the most widely used mouse models of arthritis, and it is complement-dependent. We found that mice developing CAIA also developed spinal lesions similar to those found in AxSpA. To induce CAIA, mice were injected intraperitoneally at day 0 with anti-collagen Abs, followed by LPS injection at day 3. CAIA mice demonstrated a significant kyphosis through the spine, as well as hypertrophic cartilage and osseous damage of the intravertebral joints. Immunohistochemical staining of the kyphotic area revealed increased complement C3 deposition and macrophage infiltration, with localization to the intravertebral joint margins. Near Infrared (NIR) in vivo imaging showed that anti-collagen Abs conjugated with IRDye® 800CW not only localized to cartilage surface in the joints but also to the spine in arthritic mice. We report here a novel preclinical mouse model in which, associated with the induction of CAIA, mice also exhibited salient features of AxSpA; this new experimental model of AxSpA may allow investigators to shed light on the local causal mechanisms of AxSpA bone and soft tissue changes as well as treatment.

Clinical Experience of 3T Breast MRI in Detecting the Additional Lesions in Breast Cancer Patients (유방암 환자에서 추가 병변 평가를 위한 3 테슬러 유방자기공명영상의 임상적 경험)

  • Lee, Ji-Hye;Kim, Sung-Hun;Kang, Bong-Joo;Choi, Jae-Jeong;Lee, Ah-Won
    • Investigative Magnetic Resonance Imaging
    • /
    • v.14 no.2
    • /
    • pp.121-125
    • /
    • 2010
  • Purpose : The purpose of this study was to evaluate the diagnostic accuracy of 3.0-T breast MRI for detecting additional breast cancer soon after the initial diagnosis of breast cancer. Materials and Methods : From March to June 2009, 101 patients recently diagnosed breast cancer underwent breast MRI and surgery. Parameters analyzed on MRI were total extent of tumor, suspicious findings of multifocal, multicentric, or contralateral cancer. The diagnosis of MRI-detected cancer was confirmed by means of biopsy or surgical specimen evaluation after the localization. Results : MRI showed 37 additional suspicious findings in 34 patients. Twenty nine findings were true-positive (29/37, 78.4%), including 16 cases of multifocality, 11 cases of multicentricity and 2 cases of contralateral cancer. Among these cancers, 13 (44.8%) were ductal carcinoma in situ (DCIS) and 16 (55.1%) were infiltrating cancer. Eight findings were false-positive (8/37, 21.6%) including 6 cases of benign disease and 2 cases of high-risk lesions. Conclusion : In women with recently diagnosed breast cancer, 3.0-T MR imaging showed additional suspicious findings in 33.7%. The sensitivity and specificity for detecting additional breast cancer was 100% and 89.3%, respectively.

Localization of Bilateral Hemisphere Lesion Using Combined Transcranial Magnetic Stimulation and Diffusion Tensor Imaging: Report of Two Cases (경두개 자기자극과 확산텐서 신경섬유로 검사를 통한 대뇌 병변의 국소화: 증례보고)

  • Lee, Hyung Nam;Oh, Young-Bin;Kim, Gi-Wook;Won, Yu Hui;Ko, Myoung-Hwan;Seo, Jeong-Hwan;Park, Sung-Hee
    • Journal of Electrodiagnosis and Neuromuscular Diseases
    • /
    • v.20 no.2
    • /
    • pp.106-111
    • /
    • 2018
  • Transcranial magnetic stimulation (TMS) has been a gold standard for investigating central motor pathways in humans. Diffusion tensor imaging with fiber tractography (DTI FT) is known for its usefulness in detecting white matter lesion in vivo. We investigated the clinical usefulness of elucidating the integrity and continuity of corticospinal tract (CST) by combined use of TMS and DTI FT in this study. We report two cases who have presented with left hemiparesis and evaluated by both TMS and DTI FT; 10-year-old boy with Mitochondrial Encephalomyopathy with Lactic Acidosis and Stroke-like episode syndrome and 20-year-old woman with traumatic brain injury. Combined use of TMS and DTI FT successfully led to localize the brain lesion that might cause motor impairment in patients with abnormal signal intensities in MRI. The results of this study suggest that TMS and DTI FT might provide the detailed information between function and anatomy of the CST, complementarily.