• Title/Summary/Keyword: Single photon emission tomography (SPECT)

Search Result 139, Processing Time 0.025 seconds

Functional Imaging of the Multidrug Resistance In Vivo (기능적 영상술을 이용한 다약제 내성의 체내 진단)

  • Lee, Jea-Tae
    • 대한핵의학회:학술대회논문집
    • /
    • 2001.05a
    • /
    • pp.66-75
    • /
    • 2001
  • Although diverse mechanisms are involved in multidrug resistance for chemotherapeutic drugs, the development of cellular P-glycoprotein(Pgp) and multidrug-resistance associated protein (MRP) are important factors in the chemotherapy failure to cancer. Various detection assays provide information about the presence of drug efflux pumps at the mRNA and protein levels. However these methods do not yield information about dynamic function of Pgp and MRP un vivo. Single photon emission tomography (SPECT) and positron emission tomography (PET) are available for the detection of Pgp and MRP-mediated transport. $^{99m}Tc$-sestaMIBl and other $^{99m}Tc$-radiopharmaceuticals are substrates for Pgp and MRP, and have been used in clinical studies for tumor imaging, and to visualize blockade of Pgp-mediated transport after modulation of Pgp pump. Colchicine, verapamil and daunorubicin labeled with $^{11}C$ have been evaluated for the quantification of Pgp-mediated transport with PET in vivo and reported to be feasible substrates with which to image Pgp function in tumors. Leukotrienes are specific substrates for MRP and N-$[^{11}C]$acetyl-leukotriene E4 provides an opportunity to study MRP function non-invasively in vivo. Results obtained from recent publications are reviewed to confirm the feasibility of using SPECT and PET to study the functionality of MDR transporters in vivo.

  • PDF

Spect Assessment of Regional Cerebral Perfusion Abnormality in Head Injury (두부외상 환자에서 HMPAO-SPECT를 이용한 국소 뇌혈류 변화의 평가)

  • Lee, Kyung-Han;Kim, Chul-Hee;Chang, Ha-Sung
    • The Korean Journal of Nuclear Medicine
    • /
    • v.26 no.2
    • /
    • pp.235-243
    • /
    • 1992
  • Patterns of abnormality in regional cerebral perfusion and its relation to clinical severity was evaluated with 32 head injury patients using $^{99m}Tc-HMPAO$ single photon emission tomography (SPECT). The findings were compared with computed tomography (CT) done within 48 hours of each SPECT study. The initial SPECT study was done within 7 days of injury in 16 cases, between 1 week and 2 months in 12, and after over 2 months in 4. Nineteen of the patients underwent followup SPECT and CT after a mean interval of 1 to 2 months. The initial SPECT showed abnormalities in 96% (31/32) of the patients while CT showed abnormal findings in only 81% (26/32). There were a total of 54 supratentorial SPECT lesions in all. Ninity percent (49/54) of these were of regional hypoperfusion, while 5 lesions showed focal hyperperfusion. The lesions were most often localized in the frontal and temporal lobes. Fifty five percent (30/54) were areas not detected as a lesion on CT. Cerebellar diaschisis was observed in 50% (16/32) of the patients. The degree of perfusion abnormality was quantified by the product of differential activity and a size factor. Correlation between the degree of perfusion abnormality and the clinical severity (Glasgow coma scale) failed to show statistical significance (p=0.053). The amount of change in the degree of perfusion abnormality on follow up SPECT was compared to the amount of change in clinical severity. Perfusion abnormality showed a tendancy to improve in most patients, and the degree of improvement showed significant correlation with the amount of clinical improvement (p < 0.01).

  • PDF

High-Performance Compton SPECT Using Both Photoelectric and Compton Scattering Events

  • Lee, Taewoong;Kim, Younghak;Lee, Wonho
    • Journal of the Korean Physical Society
    • /
    • v.73 no.9
    • /
    • pp.1393-1398
    • /
    • 2018
  • In conventional single-photon emission computed tomography (SPECT), only the photoelectric events in the detectors are used for image reconstruction. However, if the $^{131}I$ isotope, which emits high-energy radiations (364, 637, and 723 keV), is used in nuclear medicine, both photoelectric and Compton scattering events can be used for image reconstruction. The purpose of our work is to perform simulations for Compton SPECT by using the Geant4 application for tomographic emission (GATE). The performance of Compton SPECT is evaluated and compared with that of conventional SPECT. The Compton SPECT unit has an area of $12cm{\times}12cm$ with four gantry heads. Each head is composed of a 2-cm tungsten collimator and a $40{\times}40$ array of CdZnTe (CZT) crystals with a $3{\times}3mm^2$ area and a 6-mm thickness. Compton SPECT can use not only the photoelectric effect but also the Compton scattering effect for image reconstruction. The correct sequential order of the interactions used for image reconstruction is determined using the angular resolution measurement (ARM) method and the energies deposited in each detector. In all the results of simulations using spherical volume sources of various diameters, the reconstructed images of Compton SPECT show higher signal-to-noise ratios (SNRs) without degradation of the image resolution when compared to those of conventional SPECT because the effective count for image reconstruction is higher. For a Derenzo-like phantom, the reconstructed images for different modalities are compared by visual inspection and by using their projected histograms in the X-direction of the reconstructed images.

A study on image registration and fusion of MRI and SPECT/PET (뇌의 단일 광자 방출 전산화 단층촬영 영상, 양전자 방출 단층 촬영 영상 그리고 핵자기공명 영상의 융합과 등록에 관한 연구)

  • Joo, Ra-Hyung;Choi, Yong;Kwon, Soo-Il;Heo, Soo-Jin
    • Progress in Medical Physics
    • /
    • v.9 no.1
    • /
    • pp.47-53
    • /
    • 1998
  • Nuclear Medicine Images have comparatively poor spatial resolution, making it difficult to relate the functional information which they contain to precise anatomical structures. Anatomical structures useful in the interpretation of SPECT /PET Images were radiolabelled. PET/SPECT Images Provide functional information, whereas MRI mainly demonstrate morphology and anatomical. Fusion or Image Registration improves the information obtained by correlating images from various modalities. Brain Scan were studied on one or more occations using MRI and SPECT. The data were aligned using a point pair methods and surface matching. SPECT and MR Images was tested using a three dimensional water fillable Hoffman Brain Phantom with small marker and PET and MR Image was tested using a patient data. Registration of SPECT and MR Images is feasible and allows more accurate anatomic assessment of sites of abnormal uptake in radiolabeled studies. Point based registration was accurate and easily implemented three dimensional registration of multimodality data set for fusion of clinical anatomic and functional imaging modalities. Accuracy of a surface matching algorithm and homologous feature pair matching for three dimensional image registration of Single Photon Emission Computed Tomography Emission Computed Tomography (SPECT), Positron Emission Tomography (PET) and Magnetic Resonance Images(MRD was tested using a three dimensional water fill able brain phantom and Patients data. Transformation parameter for translation and scaling were determined by homologous feature point pair to match each SPECT and PET scan with MR images.

  • PDF

Post-Coronary Artery Bypass Grafting Myocardial Ischemia Caused by an Overgrown Left Internal Thoracic Artery Side Branch

  • Kim, Eung Re;Oh, Se Jin;Kang, Hyun-Jae;Kim, Ki-Bong
    • Journal of Chest Surgery
    • /
    • v.47 no.5
    • /
    • pp.465-467
    • /
    • 2014
  • We present a patient who developed recurrent angina after coronary artery bypass grafting (CABG). Myocardial single-photon emission computed tomography (SPECT) demonstrated deterioration in the myocardial perfusion, and coronary angiography revealed an overgrown side branch of the grafted left internal thoracic artery (ITA); otherwise, there were no significant changes compared with previous imaging studies obtained after the CABG. After percutaneous embolization of the grafted left ITA side branch, the angina was resolved and myocardial SPECT showed improved perfusion.

Spect-guidance to Reduce Radioactive Dose to Functioning Lung for Stage III Non-small Cell Lung Cancer

  • Wang, Zhong-Tang;Wei, Li-Li;Ding, Xiu-Ping;Sun, Ming-Ping;Sun, Hong-Fu;Li, Bao-Sheng
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.2
    • /
    • pp.1061-1065
    • /
    • 2013
  • Objective: To investigate the treatment effect of additional information obtained by single photon emission computed tomography (SPECT) lung perfusion imaging (LPI) in the radiotherapy planning process for patients with stage III non-small cell lung cancer (NSCLC). Methods: 39 patients with stage III NSCLC were enrolled. Gross tumor volume (GTV) was outlined by SPECT/CT images, SPECT-LPIs being used to define functional lung (FL) and non-functional lung (NFL) regions. Two sets of IMRT plans were designed to deliver 64Gy to PTV. One was a regular IMRT plan using CT images only (Plan 1), and the other was a corresponding IMRT plan using co-registered images (Plan 2). $FL_{Vx}$ (the % volume of functional lung receiving ${\geq}$x Gy) and $WL_{Vx}$ (% volume of whole lung to receive ${\geq}$x Gy) were compared by paired Student's t test. Kendalls correlation was used to analyze the factor (s) related with the FLV20 decrease. Results: Compared with plan 1, both $WL_{Vx}$ and $FL_{Vx}$ were decreased in plan 2. $WL_{V10}$, $WL_{V15}$, $WL_{V20}$, $WL_{V25}$, $WL_{V30}$ and $WL_{V35}$ decreased 9.7%, 13.8%, 17.2%, 12.9%, 9.8% and 9.8%, and $FL_{V10}$, $FL_{V15}$, $FL_{V20}$, $FL_{V25}$, $FL_{V30}$ and $FL_{V35}$ decreased 10.8%, 14.6%, 17.3%, 14.5%, 14.5% and 10.5%. $FL_{Vx}$ decreased significantly compared with $WL_{Vx}$. There were significant differences in $WL_{V10}$, $WL_{V15}$, $WL_{V20}$, $WL_{V25}$, $WL_{V3}$ and $FL_{V10}$, $FL_{V15}$, $FL_{V20}$, $FL_{V25}$, $FL_{V30}$ between plan 1 and plan 2 (P=0.002, 0.000, 0.000, 0.005, 0.027 and 0.002, 0.000, 0.000, 0.006, 0.010). According to Kendall correlation analysis, NFL had a negative relation with the percentage FLV20 decrease (r=-0.559, P<0.01), while the distance of PTV and NFL center had a significantly positive relation with the percentage of FLV20 decrease (r=0.768, P<0.01). Conclusion: Routine use of SPECT-LPI for patients undergoing radiotherapy planning for stage III NSCLC appears warranted.

Diagnosing Symptomatic Accessory Tarsal Bones Using SPECT/CT (SPECT/CT를 이용한 증후성 족부 부골의 진단)

  • Kim, Ryuh-Sup;Kang, Joon-Soon;Kim, Young-Tae;Kim, Bom-Soo
    • Journal of Korean Foot and Ankle Society
    • /
    • v.15 no.4
    • /
    • pp.212-216
    • /
    • 2011
  • Purpose: This study was designed to analyze the usefulness of Single Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) in diagnosing symptomatic accessory tarsal bones. Materials and Methods: Twenty four feet (16 patients) with symptomatic accessory navicular and/or os trigonum, who agreed to take SPECT/CT, were included in this study. Fifteen feet had accessory navicular, five had os trigonum, and four had both. According to the uptake in the SPECT/CT, 11 feet were classified into high and 13 into low uptake groups. The low uptake group was treated non-operatively, while the high uptake group received operations when initial conservative management failed. A modified Kidner procedure was performed for accessory navicular and arthroscopic excision was done for os trigonum. After a mean follow-up of 6.8 (range, 3~13) months, the American Orthopaedic Foot and Ankle Society (AOFAS) score and the Visual Analogue Scale (VAS) for pain were compared. Results: Patients in the high uptake group had a higher initial mean VAS score ($7.0{\pm}0.8$ vs $2.2{\pm}0.9$, p<0.05) and a lower initial mean AOFAS score ($45.9{\pm}9.2$ vs $83.9{\pm}4.2$, p<0.05) compared to the low uptake group. All patients in the low uptake group improved after non-operative treatment. Seven patients underwent operations and had a decreased VAS ($1.6{\pm}0.5$) and an increased AOFAS score ($88.3{\pm}1.8$) at the last follow-up. Four patients in the high uptake group demonstrated erratic symptoms. Conclusion: SPECT/CT can be a useful diagnostic tool and helpful in designing treatment plans for symptomatic accessory navicular and os trigonum.

Daily adaptive proton therapy: Feasibility study of detection of tumor variations based on tomographic imaging of prompt gamma emission from proton-boron fusion reaction

  • Choi, Min-Geon;Law, Martin;Djeng, Shin-Kien;Kim, Moo-Sub;Shin, Han-Back;Choe, Bo-Young;Yoon, Do-Kun;Suh, Tae Suk
    • Nuclear Engineering and Technology
    • /
    • v.54 no.8
    • /
    • pp.3006-3016
    • /
    • 2022
  • In this study, the images of specific prompt gamma (PG)-rays of 719 keV emitted from proton-boron reactions were analyzed using single-photon emission computed tomography (SPECT). Quantitative evaluation of the images verified the detection of anatomical changes in tumors, one of the important factors in daily adaptive proton therapy (DAPT) and verified the possibility of application of the PG-ray images to DAPT. Six scenarios were considered based on various sizes and locations compared to the reference virtual tumor to observe the anatomical alterations in the virtual tumor. Subsequently, PG-rays SPECT images were acquired using the modified ordered subset expectation-maximization algorithm, and these were evaluated using quantitative analysis methods. The results confirmed that the pixel range and location of the highest value of the normalized pixel in the PG-rays SPECT image profile changed according to the size and location of the virtual tumor. Moreover, the alterations in the virtual tumor size and location in the PG-rays SPECT images were similar to the true size and location alterations set in the phantom. Based on the above results, the tumor anatomical alterations in DAPT could be adequately detected and verified through SPECT imaging using the 719 keV PG-rays acquired during treatment.

99mTc-3PRGD2 SPECT/CT Imaging for Diagnosing Lymph Node Metastasis of Primary Malignant Lung Tumors

  • Liming Xiao;Shupeng Yu;Weina Xu;Yishan Sun;Jun Xin
    • Korean Journal of Radiology
    • /
    • v.24 no.11
    • /
    • pp.1142-1150
    • /
    • 2023
  • Objective: To evaluate 99mtechnetium-three polyethylene glycol spacers-arginine-glycine-aspartic acid (99mTc-3PRGD2) single-photon emission computed tomography (SPECT)/computed tomography (CT) imaging for diagnosing lymph node metastasis of primary malignant lung neoplasms. Materials and Methods: We prospectively enrolled 26 patients with primary malignant lung tumors who underwent 99mTc-3PRGD2 SPECT/CT and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/CT imaging. Both imaging methods were analyzed in qualitative (visual dichotomous and 5-point grades for lymph nodes and lung tumors, respectively) and semiquantitative (maximum tissue-to-background radioactive count) manners for the lymph nodes and lung tumors. The performance of the differentiation of lymph nodes with and without metastasis was determined at the per-lymph node station and per-patient levels using histopathological results as the reference standard. Results: Total 42 stations had metastatic lymph nodes and 136 stations had benign lymph nodes. The differences between metastatic and benign lymph nodes in the visual qualitative and semiquantitative analyses of 99mTc-3PRGD2 SPECT/CT and 18F-FDG PET/CT were statistically significant (all P < 0.001). The area under the receiver operating characteristic curve (AUC) in the semi-quantitative analysis of 99mTc-3PRGD2 SPECT/CT was 0.908 (95% confidence interval [CI], 0.851-0.966), and the sensitivity, specificity, positive predictive value, and negative predictive value were 0.86 (36/42), 0.88 (120/136), 0.69 (36/52), and 0.95 (120/126), respectively. Among the 26 patients (including two patients each with two lung tumors), 15 had pathologically confirmed lymph node metastasis. The difference between primary lung lesions in patients with and without lymph node metastasis was statistically significant only in the semi-quantitative analysis of 99mTc-3PRGD2 SPECT/CT (P = 0.007), with an AUC of 0.807 (95% CI, 0.641-0.974). Conclusion: 99mTc-3PRGD2 SPECT/CT imaging may notably perform in the direct diagnosis of lymph node metastasis of primary malignant lung tumors and indirectly predict the presence of lymph node metastasis through uptake in the primary lesions.

The acupuncture mechanism related brain in Medline and the journal of Korean acupuncture & moxibustion (PubMed와 대한침구학회지(大韓針灸學會誌) 논문(論文) 검색(檢索)을 통(通)한 침요법(鍼療法)과 뇌(腦)와의 관계(關係)에 대한 연구동향(硏究動向) 고찰(考察))

  • Kim, Hoo-Dong;Koh, Hyung-Kyun;Kim, Chang-Hwan
    • Journal of Acupuncture Research
    • /
    • v.18 no.4
    • /
    • pp.188-200
    • /
    • 2001
  • Background and Objetive : Acupuncture is a valuable method of oriental medicine with broad application in many disease. It is based on the experiences of traditional oriental medicine as well as on experimentally proven biological (biochemical and neurophysiological) effects. Acupuncture theory has been explained by the meridian system that is thought to be linked with particular organs. However, in western medicine it is held that many disorders are either controlled or affected by the brain. Material and Method : In order to review the studies concerned with the mechanism related brain, we have referred to the Pubmed site and the Journal of Korean acupuncture and moxibustion Result and Conculsion : Among the 12 studies in the Journal of Korean acupuncture and moxibustion, 8 papers related neurotransmitters were done by experimental study, 4 papers related brain mapping were done by clinical study. Among the 8 studies related brain mapping in the Pubmed site, 6 clinical studies using functional magnetic resonance imaging(fMRI) were done and I clinical study using single-photon emission computed tomography(SPECT) was done, I paper was review article. By the above result, it would be needed further research on the acupuncture mechanism related brain using SPECT, fMRI, positron emission tomography(PET) etc.

  • PDF