WorldWideScience

Sample records for tumors ct imaging

  1. Segmentation of liver tumors on CT images

    International Nuclear Information System (INIS)

    Pescia, D.

    2011-01-01

    This thesis is dedicated to 3D segmentation of liver tumors in CT images. This is a task of great clinical interest since it allows physicians benefiting from reproducible and reliable methods for segmenting such lesions. Accurate segmentation would indeed help them during the evaluation of the lesions, the choice of treatment and treatment planning. Such a complex segmentation task should cope with three main scientific challenges: (i) the highly variable shape of the structures being sought, (ii) their similarity of appearance compared with their surrounding medium and finally (iii) the low signal to noise ratio being observed in these images. This problem is addressed in a clinical context through a two step approach, consisting of the segmentation of the entire liver envelope, before segmenting the tumors which are present within the envelope. We begin by proposing an atlas-based approach for computing pathological liver envelopes. Initially images are pre-processed to compute the envelopes that wrap around binary masks in an attempt to obtain liver envelopes from estimated segmentation of healthy liver parenchyma. A new statistical atlas is then introduced and used to segmentation through its diffeomorphic registration to the new image. This segmentation is achieved through the combination of image matching costs as well as spatial and appearance prior using a multi-scale approach with MRF. The second step of our approach is dedicated to lesions segmentation contained within the envelopes using a combination of machine learning techniques and graph based methods. First, an appropriate feature space is considered that involves texture descriptors being determined through filtering using various scales and orientations. Then, state of the art machine learning techniques are used to determine the most relevant features, as well as the hyper plane that separates the feature space of tumoral voxels to the ones corresponding to healthy tissues. Segmentation is then

  2. PET/CT imaging in head and neck tumors

    International Nuclear Information System (INIS)

    Roedel, R.; Palmedo, H.; Reichmann, K.; Reinhardt, M.J.; Biersack, H.J.; Straehler-Pohl, H.J.; Jaeger, U.

    2004-01-01

    To evaluate the usefulness of combined PET/CT examinations for detection of malignant tumors and their metastases in head and neck oncology. 51 patients received whole body scans on a dual modality PET/CT system. CT was performed without i.v. contrast. The results were compared concerning the diagnostic impact of native CT scan on FDG-PET images and the additional value of fused imaging. From 153 lesions were 97 classified as malignant on CT and 136 on FDG/PET images, as suspicious for malignancy in 33 on CT and 7 on FDG-PET and as benign in 23 on CT and 10 on FDG-PET. With combined PET/CT all primary and recurrent tumors could be found, the detection rate in patients with unknown primary tumors was 45%. Compared to PET or CT alone the sensitivity, specifity and accuracy could be significantly improved by means of combined PET/CT. Fused PET/CT imaging with [F18]-FDG and native CT-scanning enables accurate diagnosis in 93% of lesions and 90% of patients with head and neck oncology. (orig.) [de

  3. Imaging of head and neck tumors -- methods: CT, spiral-CT, multislice-spiral-CT

    International Nuclear Information System (INIS)

    Baum, Ulrich; Greess, Holger; Lell, Michael; Noemayr, Anton; Lenz, Martin

    2000-01-01

    Spiral-CT is standard for imaging neck tumors. In correspondence with other groups we routinely use spiral-CT with thin slices (3 mm), a pitch of 1.3-1.5 and an overlapping reconstruction increment (2-3 mm). In patients with dental fillings a short additional spiral parallel to the corpus of the mandible reduces artifacts behind the dental arches and improves the diagnostic value of CT. For the assessment of the base of the skull, the orbital floor, the palate and paranasal sinuses an additional examination in the coronal plane is helpful. Secondary coronal reconstructions of axial scans are helpful in the evaluation of the crossing of the midline by small tumors of the tongue base or palate. For an optimal vascular or tissue contrast a sufficient volume of contrast medium and a start delay greater than 70-80 s are necessary. In our opinion the best results can be achieved with a volume of 150 ml, a flow of 2.5 ml/s and a start delay of 80 s. Dynamic enhanced CT is only necessary in some special cases. There is clear indication for dynamic enhanced CT where a glomus tumor is suspected. Additional functional CT imaging during i-phonation and/or Valsalva's maneuver are of great importance to prove vocal cords mobility. Therefore, imaging during i-phonation is an elemental part of every thorough examination of the hypopharynx and larynx region. Multislice-spiral-CT allows almost isotropic imaging of the head and neck region and improves the assessment of tumor spread and lymph node metastases in arbitrary oblique planes. Thin structures (the base of the skull, the orbital floor, the hard palate) as well as the floor of the mouth can be evaluated sufficiently with multiplanar reformations. Usually, additional coronal scanning is not necessary with multislice-spiral-CT. Multislice-spiral-CT is especially advantageous in defining the critical relationships of tumor and lymph node metastases and for functional imaging of the hypopharynx and larynx not only in the

  4. CT and MR imaging findings of palatal tumors

    International Nuclear Information System (INIS)

    Kato, Hiroki; Kanematsu, Masayuki; Makita, Hiroki; Kato, Keizo; Hatakeyama, Daijiro; Shibata, Toshiyuki; Mizuta, Keisuke; Aoki, Mitsuhiro

    2014-01-01

    Palatal tumors commonly arise from the minor salivary glands, and benign tumors account for approximately half of all minor salivary gland tumors. Minor salivary gland tumors have an affinity for the posterior hard palate and soft palate and virtually never arise in the midline, probably because of the distribution of palatal salivary glands. The majority of benign salivary gland tumors of the palate are pleomorphic adenomas, while the most common malignant salivary gland tumor is adenoid cystic carcinoma, followed by mucoepidermoid carcinoma, adenocarcinoma, and polymorphous low-grade adenocarcinoma. Epithelial tumors frequently arise from the soft palate. The majority of benign epithelial tumors of the palate are papillomas, while most malignant epithelial tumors are squamous cell carcinomas. Various types of mesenchymal tumors, including fibromas, lipomas, schwannomas, neurofibromas, hemangiomas, and lymphangiomas, also involve the palate. This article describes the CT and MR findings of benign and malignant palatal tumors

  5. CT and MR imaging findings of palatal tumors

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Hiroki, E-mail: hkato@gifu-u.ac.jp [Department of Radiology, Gifu University School of Medicine, 1-1 Yanagido, Gifu 501-1194 (Japan); Kanematsu, Masayuki, E-mail: masa_gif@yahoo.co.jp [Department of Radiology, Gifu University School of Medicine, 1-1 Yanagido, Gifu 501-1194 (Japan); High-level Imaging Diagnosis Center, Gifu University Hospital, 1-1 Yanagido, Gifu 501-1194 (Japan); Makita, Hiroki, E-mail: makitah@gifu-u.ac.jp [Department of Oral and Maxillofacial Sciences, Gifu University School of Medicine, Gifu (Japan); Kato, Keizo, E-mail: keizo@gifu-u.ac.jp [Department of Oral and Maxillofacial Sciences, Gifu University School of Medicine, Gifu (Japan); Hatakeyama, Daijiro, E-mail: hatakeya@gifu-u.ac.jp [Department of Oral and Maxillofacial Sciences, Gifu University School of Medicine, Gifu (Japan); Shibata, Toshiyuki, E-mail: shibat@gifu-u.ac.jp [Department of Oral and Maxillofacial Sciences, Gifu University School of Medicine, Gifu (Japan); Mizuta, Keisuke, E-mail: kmizuta@gifu-u.ac.jp [Department of Otolaryngology, Gifu University School of Medicine, Gifu (Japan); Aoki, Mitsuhiro, E-mail: aoki@gifu-u.ac.jp [Department of Otolaryngology, Gifu University School of Medicine, Gifu (Japan)

    2014-03-15

    Palatal tumors commonly arise from the minor salivary glands, and benign tumors account for approximately half of all minor salivary gland tumors. Minor salivary gland tumors have an affinity for the posterior hard palate and soft palate and virtually never arise in the midline, probably because of the distribution of palatal salivary glands. The majority of benign salivary gland tumors of the palate are pleomorphic adenomas, while the most common malignant salivary gland tumor is adenoid cystic carcinoma, followed by mucoepidermoid carcinoma, adenocarcinoma, and polymorphous low-grade adenocarcinoma. Epithelial tumors frequently arise from the soft palate. The majority of benign epithelial tumors of the palate are papillomas, while most malignant epithelial tumors are squamous cell carcinomas. Various types of mesenchymal tumors, including fibromas, lipomas, schwannomas, neurofibromas, hemangiomas, and lymphangiomas, also involve the palate. This article describes the CT and MR findings of benign and malignant palatal tumors.

  6. Helical 3D-CT images of soft tissue tumors in the hand

    Energy Technology Data Exchange (ETDEWEB)

    Otani, Kazuhiro; Kikuchi, Hiraku; Tan, Akihiro; Hamanishi, Chiaki; Tanaka, Seisuke [Kinki Univ., Osaka-Sayama (Japan). School of Medicine

    2000-02-01

    X-ray, ultrasonograph CT, MRI and angiography are used to detect tumoral lesions. Recently, helical CT has been revealed to be a useful method for the diagnosis and preoperative evaluation of soft tissue tumors, by which high quality and accurate three dimensional (3D) images can be obtained quickly. We analyzed the preoperative 3D-CT images of soft tissue tumors in the hands of 11 cases (hemangioma in 6 cases, giant cell tumor, lipoma, angiofibroma, chondrosarcoma and malignant fibro-histiocytoma in one case each). Enhanced 3D-CT clearly visualized hemangiomas and solid tumors from the surrounding tissues. The tumors could easily be observed from any direction and color-coded according to the CT number. Helical 3D-CT was thus confirmed to be useful for the diagnosis and preoperative planning by indicating the details of tumor expansion into surrounding tissues. (author)

  7. Holographic observation of magnetic resonance image CT of intracranial tumors

    International Nuclear Information System (INIS)

    Iwata, Kinjiro; Watanabe, Saburo; Yuasa, Hiromi; Yamada, Takahisa; Hoshino, Daisaku; Suzuki, Masane; Saito, Takayuki.

    1987-01-01

    In 1975, we developed a new method of 3-dimensional observation of CT pictures using Gabor's holography principle. In this study, we are reporting our experience with the multi-tomogram holography using magnetic resonance image CT in order to reconstruct 3-dimensional viewing of the central nervous system and intracranial lesions. (J.P.N.)

  8. Comparison of MR imaging and CT in the evaluation of uterine tumors

    International Nuclear Information System (INIS)

    Janus, C.L.; Dottino, P.; Brodman, M.; Goodman, H.; Gendal, E.S.; Rabinowitz, J.G.

    1987-01-01

    The authors compared the usefulness of MR imaging and CT in staging uterine tumors. Forty women with known cervical carcinoma, endometrial cancer, or leiomyosarcoma underwent CT and MR imaging within 1 week prior to surgery. MR imaging was better than CT for localizing tumors to the endometrium of myometrium and in the evaluation of lymph node involvement and extension to the cervix and parametria. MR imaging, with its superior ability to demonstrate pelvic anatomy and its lack of ionizing radiation and risk from iodinated contrast media, has an important place in the staging of uterine tumors

  9. Development of an automated extraction method for liver tumors in three dimensional multiphase multislice CT images

    International Nuclear Information System (INIS)

    Nakagawa, Junya; Shimizu, Akinobu; Kobatake, Hidefumi

    2004-01-01

    This paper proposes a tumor detection method using four phase three dimensional (3D) CT images of livers, i.e. non-contrast, early, portal, and late phase images. The method extracts liver regions from the four phase images and enhances tumors in the livers using a 3D adaptive convergence index filter. Then it detects local maximum points and extracts tumor candidates by a region growing method. Subsequently several features of the candidates are measured and each candidate is classified into true tumor or normal tissue based on Mahalanobis distances. Above processes except liver region extraction are applied to four phase images, independently and four resultant images are integrated into one. We applied the proposed method to 3D abdominal CT images of ten patients obtained with multi-detector row CT scanner and confirmed that tumor detection rate was 100% without false positives, which was quite promising results. (author)

  10. Granular Cell Tumor of the Neurohypophysis: A Case Report with Magnetic Resonance and CT Imaging Findings

    Energy Technology Data Exchange (ETDEWEB)

    Choo, Ka Yeon; Lee, Sun Jin; Ahn, Kook Jin; Jung, So Lyung; Kim, Bum Soo [Dept. of Radiology, Seoul St.Mary' s Hospital, The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of); Lee, Yeon Soo [Dept. of Pathology, Seoul St.Mary' s Hospital, The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of); Jeun, Shin Soo [Dept. of Neurosurgery, Seoul St.Mary' s Hospital, The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of)

    2011-11-15

    A granular cell tumor (GCT) usually occurs as a small, solitary, nodular tumor and is more prevalent in adult females. The authors report the magnetic resonance (MR) and CT imaging findings in a 61-year-old woman with GCT of the neurohypophysis presenting with a history of reduced visual acuity in her right eye. MR images showed a suprasellar mass with an isointense signal on a T1-weighted image and an hypointense signal on a T2-weighted image. The histopathological examination revealed a granular cell tumor. In this article, the MR and CT imaging findings of GCT of the neurohypophysis with the literature reviews are discussed.

  11. Granular Cell Tumor of the Neurohypophysis: A Case Report with Magnetic Resonance and CT Imaging Findings

    International Nuclear Information System (INIS)

    Choo, Ka Yeon; Lee, Sun Jin; Ahn, Kook Jin; Jung, So Lyung; Kim, Bum Soo; Lee, Yeon Soo; Jeun, Shin Soo

    2011-01-01

    A granular cell tumor (GCT) usually occurs as a small, solitary, nodular tumor and is more prevalent in adult females. The authors report the magnetic resonance (MR) and CT imaging findings in a 61-year-old woman with GCT of the neurohypophysis presenting with a history of reduced visual acuity in her right eye. MR images showed a suprasellar mass with an isointense signal on a T1-weighted image and an hypointense signal on a T2-weighted image. The histopathological examination revealed a granular cell tumor. In this article, the MR and CT imaging findings of GCT of the neurohypophysis with the literature reviews are discussed.

  12. Contrast-enhanced helical CT of the pancreas. Optimal timing of imaging for pancreatic tumor evaluation

    International Nuclear Information System (INIS)

    Koide, Kazuki; Sekiguchi, Ryuzo

    2001-01-01

    We performed three-phase helical CT in patients suspected pancreatic tumors and investigated the optimal timing of imaging for evaluation of the pancreatic mass. The pancreatic-phase was superior in detecting pancreatic tumors, including islet cell tumors that may show strong enhancement. However, portal vein-phase imaging was also superior in 16.7% of our patients. Taking into account examination for hepatic metastasis, helical CT of any pancreatic tumor should include images obtained in the pancreatic and portal vein phases. (author)

  13. CT and MR imaging findings of endocrine tumor of the pancreas according to WHO classification

    International Nuclear Information System (INIS)

    Rha, Sung Eun; Jung, Seung Eun; Lee, Kang Hoon; Ku, Young Mi; Byun, Jae Young; Lee, Jae Mun

    2007-01-01

    The pancreatic endocrine tumors are rare neuroendocrine tumors of the pancreas originating from totipotential stem cells or differentiated mature endocrine cells within the exocrine gland. Endocrine tumors are usually classified into functioning and non-functioning tumors and presents with a range of benignity or malignancy. In this article, we present the various CT and MR imaging findings of endocrine tumors of pancreas according to recent WHO classification

  14. Computer-aided analysis of CT images for the differentiation of cerebral tumors

    International Nuclear Information System (INIS)

    Michalik, M.; Michalik, S.; Bornholdt, F.

    1988-01-01

    For the integration of CT imaging into the differential diagnostics of intracranial space occupations, the selection and description of characteristics facilitating a good discrimination of serveral classes of tumors becomes a very important task. From images of 93 patients with the most frequent brain tumors the optimal set of characteristics was determined. The four most significant characteristics for the differentiation of brain tumors are 'uptake of contrast medium by the tumor', 'deliniation of the tumor contours', 'progression of the tumor' and the 'average tumor density after administration of contrast media'. Very good results were obtained for the differentiation of menigneomas with and without anaplasia and for the differentiation of meningeomas from all other tumors examined. The differentiation of the degree of malignancy for various gliomatous tumors was difficult. An accurate reclassification with the computer program was obtained for 83.4% of all tumors. (author)

  15. Automatic lung tumor segmentation on PET/CT images using fuzzy Markov random field model.

    Science.gov (United States)

    Guo, Yu; Feng, Yuanming; Sun, Jian; Zhang, Ning; Lin, Wang; Sa, Yu; Wang, Ping

    2014-01-01

    The combination of positron emission tomography (PET) and CT images provides complementary functional and anatomical information of human tissues and it has been used for better tumor volume definition of lung cancer. This paper proposed a robust method for automatic lung tumor segmentation on PET/CT images. The new method is based on fuzzy Markov random field (MRF) model. The combination of PET and CT image information is achieved by using a proper joint posterior probability distribution of observed features in the fuzzy MRF model which performs better than the commonly used Gaussian joint distribution. In this study, the PET and CT simulation images of 7 non-small cell lung cancer (NSCLC) patients were used to evaluate the proposed method. Tumor segmentations with the proposed method and manual method by an experienced radiation oncologist on the fused images were performed, respectively. Segmentation results obtained with the two methods were similar and Dice's similarity coefficient (DSC) was 0.85 ± 0.013. It has been shown that effective and automatic segmentations can be achieved with this method for lung tumors which locate near other organs with similar intensities in PET and CT images, such as when the tumors extend into chest wall or mediastinum.

  16. Automatic Lung Tumor Segmentation on PET/CT Images Using Fuzzy Markov Random Field Model

    Directory of Open Access Journals (Sweden)

    Yu Guo

    2014-01-01

    Full Text Available The combination of positron emission tomography (PET and CT images provides complementary functional and anatomical information of human tissues and it has been used for better tumor volume definition of lung cancer. This paper proposed a robust method for automatic lung tumor segmentation on PET/CT images. The new method is based on fuzzy Markov random field (MRF model. The combination of PET and CT image information is achieved by using a proper joint posterior probability distribution of observed features in the fuzzy MRF model which performs better than the commonly used Gaussian joint distribution. In this study, the PET and CT simulation images of 7 non-small cell lung cancer (NSCLC patients were used to evaluate the proposed method. Tumor segmentations with the proposed method and manual method by an experienced radiation oncologist on the fused images were performed, respectively. Segmentation results obtained with the two methods were similar and Dice’s similarity coefficient (DSC was 0.85 ± 0.013. It has been shown that effective and automatic segmentations can be achieved with this method for lung tumors which locate near other organs with similar intensities in PET and CT images, such as when the tumors extend into chest wall or mediastinum.

  17. CT and MR imaging of primary tumors of the masticator space

    International Nuclear Information System (INIS)

    Aspestrand, F.; Boysen, M.

    1992-01-01

    A retrospective study of CT and MR examinations in 14 patients with benign and malignant tumors originating in the masticator space is presented. At presentation, 12 patients revealed tumor extension to adjacent regions and spaces. Perineutral tumor spread along trigeminal nerve branches to the cavernous sinus and orbits was combined with facial pain, and/or numbness, ophthalmoplegia, and exophthalmus. Detailed analysis of tumor growth and spread, enhancement and signal features at CT and MR imaging indicated that tumor histology was, with a few exceptions, nonspecific. More extensive growth and bone destruction was noted only among malignant tumors. MR imaging was found superior to CT in delineating tumor extension due to better soft tissue contrast resolution and multiplanar imaging. Posttreatment examinations were available in 11 patients and showed long-standing regional edema of the adjacent temporal lobe and masticator muscles in 4 out of 5 patients without clinical evidence of tumor. In 6 patients, CT and MR features were found almost unchanged with only small size differences after various forms of treatment. (orig.)

  18. Improving abdomen tumor low-dose CT images using a fast dictionary learning based processing

    International Nuclear Information System (INIS)

    Chen Yang; Shi Luyao; Shu Huazhong; Luo Limin; Coatrieux, Jean-Louis; Yin Xindao; Toumoulin, Christine

    2013-01-01

    In abdomen computed tomography (CT), repeated radiation exposures are often inevitable for cancer patients who receive surgery or radiotherapy guided by CT images. Low-dose scans should thus be considered in order to avoid the harm of accumulative x-ray radiation. This work is aimed at improving abdomen tumor CT images from low-dose scans by using a fast dictionary learning (DL) based processing. Stemming from sparse representation theory, the proposed patch-based DL approach allows effective suppression of both mottled noise and streak artifacts. The experiments carried out on clinical data show that the proposed method brings encouraging improvements in abdomen low-dose CT images with tumors. (paper)

  19. CT, MRI, and FDG-PET/CT imaging findings of abdominopelvic desmoplastic small round cell tumors: Correlation with histopathologic findings

    International Nuclear Information System (INIS)

    Zhang Weidong; Li Chuanxing; Liu Qingyu; Hu Yingying; Cao Yun; Huang Jinhua

    2011-01-01

    Objective: To analyze computed tomography (CT), magnetic resonance imaging (MRI), and fluorodeoxyglucose-positron emission tomography (FDG-PET)/CT imaging features of abdominopelvic desmoplastic small round cell tumor (DSRCT) and to improve the diagnostic efficacy of these techniques for the detection of such tumor. Methods: We retrospectively analyzed 7 cases of abdominopelvic DSRCT confirmed by histopathologic analysis. Among the 7 patients, 5 patients had undergone CT scanning, 2 of which were also examined with FDG-PET/CT imaging, and 2 had undergone MRI. Unenhanced and contrast-enhanced examinations were performed in all patients, and 2 patients had also undergone dynamic CT contrast-enhanced examinations. Image characteristics, such as shape, size, number, edge, attenuation, and intensity of each lesion before and after contrast enhancement were analyzed and compared with the pathomorphology of the tumors. Results: Multiple large masses in the abdominopelvis were detected in 6 cases, and a large mass in the pelvis was detected in 1 case. Six cases showed largest mass in pelvis, and 1 case in mesentery. None of the masses had a definite organ origin. CT showed soft tissue masses with patchy foci of hypodense areas. MR T1-weighted images revealed lesions with mild hypointense areas and patchy hypointense areas in 2 cases and lesions with patchy hyperintense areas in 1 case. T2-weighted images showed lesions with mixed isointense and hyperintense areas in 1 case and lesions with mixed hypointense, isointense, and hyperintense areas in another. Contrast-enhanced CT and T1-weighted images showed mildly heterogeneous enhancement of the lesions. Other associated findings included peritoneal seeding (n = 3), peritoneal effusions (n = 3), hepatic metastasis (n = 2), bone metastasis (n = 1), and mesenteric and retroperitoneal lymphadenopathy (n = 4). FDG-PET/CT showed multiple nodular foci of increased metabolic activity in the abdominopelvic masses, in the hepatic and

  20. CT-MR image data fusion for computer assisted navigated neurosurgery of temporal bone tumors

    International Nuclear Information System (INIS)

    Nemec, Stefan Franz; Donat, Markus Alexander; Mehrain, Sheida; Friedrich, Klaus; Krestan, Christian; Matula, Christian; Imhof, Herwig; Czerny, Christian

    2007-01-01

    Purpose: To demonstrate the value of multi detector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the preoperative work up of temporal bone tumors and to present, especially, CT and MR image fusion for surgical planning and performance in computer assisted navigated neurosurgery of temporal bone tumors. Materials and methods: Fifteen patients with temporal bone tumors underwent MDCT and MRI. MDCT was performed in high-resolution bone window level setting in axial plane. The reconstructed MDCT slice thickness was 0.8 mm. MRI was performed in axial and coronal plane with T2-weighted fast spin-echo (FSE) sequences, un-enhanced and contrast-enhanced T1-weighted spin-echo (SE) sequences, and coronal T1-weighted SE sequences with fat suppression and with 3D T1-weighted gradient-echo (GE) contrast-enhanced sequences in axial plane. The 3D T1-weighted GE sequence had a slice thickness of 1 mm. Image data sets of CT and 3D T1-weighted GE sequences were merged utilizing a workstation to create CT-MR fusion images. MDCT and MR images were separately used to depict and characterize lesions. The fusion images were utilized for interventional planning and intraoperative image guidance. The intraoperative accuracy of the navigation unit was measured, defined as the deviation between the same landmark in the navigation image and the patient. Results: Tumorous lesions of bone and soft tissue were well delineated and characterized by CT and MR images. The images played a crucial role in the differentiation of benign and malignant pathologies, which consisted of 13 benign and 2 malignant tumors. The CT-MR fusion images supported the surgeon in preoperative planning and improved surgical performance. The mean intraoperative accuracy of the navigation system was 1.25 mm. Conclusion: CT and MRI are essential in the preoperative work up of temporal bone tumors. CT-MR image data fusion presents an accurate tool for planning the correct surgical procedure and is a

  1. Cross-sectional imaging with CT and/or MRI of pediatric chest tumors

    International Nuclear Information System (INIS)

    Wyttenbach, R.; Vock, P.; Tschaeppeler, H.

    1998-01-01

    The purpose of this study was to provide an overview of the spectrum of pediatric chest masses, to present the results of cross-sectional imaging with CT and/or MRI, and to define diagnostic criteria to limit differential diagnosis. Seventy-eight children with thoracic mass lesions were retrospectively evaluated using CT (72 patients) and/or MR imaging (12 patients). All masses were evaluated for tissue characteristics (attenuation values or signal intensity, enhancement, and calcification) and were differentiated according to age, gender, location, and etiology. Twenty-eight of 38 (74 %) mediastinal masses were malignant (neuroblastoma, malignant lymphoma). Thirty of 38 (79 %) pulmonary masses were metastatic in origin, all with an already known primary tumor (osteosarcoma, Wilms tumor). With one exception, all remaining pulmonary lesions were benign. Seventeen of 21 (81 %) chest wall lesions were malignant (Ewing sarcoma, primitive neuroectodermal tumor). The majority of mediastinal and chest wall tumors in children is malignant. Lung lesions are usually benign, unless a known extrapulmonary tumor suggests pulmonary metastases. Cross-sectional imaging with CT and/or MRI allows narrowing of the differential diagnosis of pediatric chest masses substantially by defining the origin and tissue characteristics. Magnetic resonance imaging is preferred for posterior mediastinal lesions, whereas CT should be used for pulmonary lesions. For the residual locations both modalities are complementary. (orig.)

  2. Automatic computer aided analysis algorithms and system for adrenal tumors on CT images.

    Science.gov (United States)

    Chai, Hanchao; Guo, Yi; Wang, Yuanyuan; Zhou, Guohui

    2017-12-04

    The adrenal tumor will disturb the secreting function of adrenocortical cells, leading to many diseases. Different kinds of adrenal tumors require different therapeutic schedules. In the practical diagnosis, it highly relies on the doctor's experience to judge the tumor type by reading the hundreds of CT images. This paper proposed an automatic computer aided analysis method for adrenal tumors detection and classification. It consisted of the automatic segmentation algorithms, the feature extraction and the classification algorithms. These algorithms were then integrated into a system and conducted on the graphic interface by using MATLAB Graphic user interface (GUI). The accuracy of the automatic computer aided segmentation and classification reached 90% on 436 CT images. The experiments proved the stability and reliability of this automatic computer aided analytic system.

  3. Molecular imaging of neuroendocrine tumors using 68Ga-labeled peptides (Somatostatin receptor PET/CT)

    International Nuclear Information System (INIS)

    Baum, R.P.; Prasad, V.; Hoersch, D.

    2009-01-01

    Receptor PET/CT using 68 Ga-labeled somatostatin analogues (DOTA-NOC, DOTA-TOC or DOTA-TATE) enables the highly sensitive molecular imaging of neuroendocrine tumors (NETs) based on the expression of somatostatin receptors and even the detection of receptor subtypes. Our experience after more than 3000 studies shows that receptor PET/CT has a significantly higher tumor detection rate than conventional scintigraphy (even in SPECT/CT technique), and that tumor lesions can be very accurately localized. By calculating standardized uptake values (SUV) - which are reproducible and investigator-independent - patients can be selected for peptide receptor radiotherapy and also the course after therapy can be controlled. Receptor-PET/CT is the most sensitive imaging modality for the detection of unknown primary tumors (CUP syndrome), which is especially true for the detection of neuroendocrine tumors of the pancreas and small bowel; whole-body staging (''one stop shop'') as well as restaging and selection of patients for peptide receptor radiotherapy can be performed using a patient-friendly procedure (examination finished within one hour) exposing the patient to less radiation than whole-body CT scanning. The 68 Ge/ 68 Ga generator has proved very reliable over the years - even in a hospital environment. The effective costs for 68 Ga labeled somatostatin analogues might be less than for scintigraphic agents, provided a certain number of studies per year are performed. The development of new tumor-specific peptides as well as of other DOTA- or NOTA-coupled radiopharmaceuticals opens a new avenue into the future: finally, the 68 Ga generator could play a similar important role for PET/CT as did the 99m Tc-Generator for conventional gamma camera imaging over the last decades. (orig.)

  4. Quantitative characterization of liver tumor radiodensity in CT images: a phantom study between two scanners

    Science.gov (United States)

    Berman, Benjamin Paul; Li, Qin; McKenney, Sarah; Fricke, Stanley Thomas; Fang, Yuan; Gavrielides, Marios A.; Petrick, Nicholas

    2018-02-01

    Quantitative assessment of tumor radiodensity is important for the clinical evaluation of contrast enhancement and treatment response, as well as for the extraction of texture-related features for image analysis or radiomics. Radiodensity estimation, Hounsfield Units (HU) in CT images, can be affected by patient factors such as tumor size, and by system factors such as acquisition and reconstruction protocols. In this project, we quantified the measurability of liver tumor HU using a 3D-printed phantom, imaged with two CT systems: Siemens Somatom Force and GE Lightspeed VCT. The phantom was printed by dithering two materials to create spherical tumors (10, 14 mm) with uniform densities (90, 95, 100, 105 HU). Image datasets were acquired at 120 kVp including 15 repeats using two matching exposures across the CT systems, and reconstructed using comparable algorithms. The radiodensity of each tumor was measured using an automated matched-filter method. We assessed the performance of each protocol using the area under the ROC curve (AUC) as the metric for distinguishing between tumors with different radiodensities. The AUC ranged from 0.8 to 1.0 and was affected by tumor size, radiodensity, and scanner; the lowest AUC values corresponded to low dose measurements of 10 mm tumors with less than 5 HU difference. The two scanners exhibited similar performance >0.9 AUC for large lesions with contrast above 7 HU, though differences were observed for the smallest and lowest contrast tumors. These results show that HU estimation should be carefully examined, considering that uncertainty in the tumor radiodensity may propagate to quantification of other characteristics, such as size and texture.

  5. The registration accuracy analysis of different CT-MRI imaging fusion method in brain tumor

    International Nuclear Information System (INIS)

    Lu Jie; Yin Yong; Shao Qian; Zhang Zicheng; Chen Jinhu; Chen Zhaoqiu

    2010-01-01

    Objective: To find an effective CT-MRI image fusion protocol in brain tumor by analyzing the registration accuracy of different methods. Methods: The simulation CT scan and MRI T 1 WI imaging of 10 brain tumor patients obtained with same position were registered by Tris-Axes landmark ,Tris-Axes landmark + manual adjustment, mutual information and mutual information + manual adjustment method. The clinical tumor volume (CTV) were contoured on both CT and MRI images respectively. The accuracy of image fusion was assessed by the mean distance of five bone markers (d 1-5 ), central position of CTV (d CTV ) the percentage of CTV overlap (P CT-MRI ) between CT and MRI images. The difference between different methods was analyzed by Freedman M non-parameter test. Results: The difference of the means d1-5 between the Tris-Axes landmark,Tris-Axes landmark plus manual adjustment,mutual information and mutual information plus manual adjustment methods were 0.28 cm ±0.12 cm, 0.15 cm ±0.02 cm, 0.25 cm± 0.19 cm, 0.10 cm ± 0.06 cm, (M = 14.41, P = 0.002). the means d CTV were 0.59 cm ± 0.28 cm, 0.60 cm± 0.32 cm, 0.58 cm ± 0.39 cm, 0.42 cm± 0.30 cm (M = 9.72, P = 0.021), the means P CT-MRI were 0.69% ±0.18%, 0.68% ±0.16%, 0.66% ±0.17%, 0.74% ±0.14% (M =14.82, P=0.002), respectively. Conclusions: Mutual information plus manual adjustment registration method was the preferable fusion method for brain tumor patients. (authors)

  6. F-18 FDG PET/CT imaging of primary hepatic neuroendocrine tumor

    Directory of Open Access Journals (Sweden)

    Katsuya Mitamura

    2015-01-01

    Full Text Available Primary hepatic neuroendocrine tumors (PHNETs are extremely rare neoplasms. Herein, we report a case of a 70-year-old man with a hepatic mass. The non-contrast computed tomography (CT image showed a low-density mass, and dynamic CT images indicated the enhancement of the mass in the arterial phase and early washout in the late phase. F18- fluorodeoxyglucose (18F-FDG positron emission tomography (PET and fused PET/CT images showed increased uptake in the hepatic mass. Whole-body 18F-FDG PET images showed no abnormal activity except for the liver lesion. Presence of an extrahepatic tumor was also ruled out by performing upper gastrointestinal endoscopy, total colonoscopy, and chest and abdominal CT. A posterior segmentectomy was performed, and histologic examination confirmed a neuroendocrine tumor (grade 1. The patient was followed up for about 2 years after the resection, and no extrahepatic lesions were radiologically found. Therefore, the patient was diagnosed with PHNET. To the best of our knowledge, no previous case of PHNET have been detected by 18F-FDG PET imaging.

  7. New method for extracting tumors in PET/CT images based on the probability distribution

    International Nuclear Information System (INIS)

    Nitta, Shuhei; Hontani, Hidekata; Hukami, Tadanori

    2006-01-01

    In this report, we propose a method for extracting tumors from PET/CT images by referring to the probability distribution of pixel values in the PET image. In the proposed method, first, the organs that normally take up fluorodeoxyglucose (FDG) (e.g., the liver, kidneys, and brain) are extracted. Then, the tumors are extracted from the images. The distribution of pixel values in PET images differs in each region of the body. Therefore, the threshold for detecting tumors is adaptively determined by referring to the distribution. We applied the proposed method to 37 cases and evaluated its performance. This report also presents the results of experiments comparing the proposed method and another method in which the pixel values are normalized for extracting tumors. (author)

  8. Edema in the retropharyngeal space associated with head and neck tumors: CT imaging characteristics

    International Nuclear Information System (INIS)

    Kurihara, Noriko; Nakamura, Mamoru; Tsuda, Masashi; Saito, Haruo; Takahashi, Shoki; Higano, Shuichi

    2005-01-01

    To determine computed tomographic (CT) imaging characteristics of retropharygeal edema, we reviewed CT images in 18 patients with head and neck tumors. Retropharyngeal edema spread craniocaudally between soft palate and upper half of thyroid cartilage in all patients. No edema fluid extended above soft palate and below thyroid cartilage. Horizontally, it spread symmetrically in ten and asymmetrically in eight patients. Predominance in asymmetrical retropharyngeal edema was found on the same side as that of unilateral predominance both in lymph nodes enlargement and jugular vein stenosis/occlusion. All patients had edema also in other cervical spaces. Edema of retropharyngeal and other spaces fluctuated synchronously. In 14 patients, as primary lesion and/or cervical lymph nodes regressed, retropharyngeal edema disappeared or decreased. Retropharyngeal edema had some imaging characteristics. With knowledge of that, we could avoid diagnostic confusion when evaluating head and neck CT images. (orig.)

  9. CT and MR imaging of gastrointestinal stromal tumor of stomach: a pictorial review

    OpenAIRE

    Gong, Jingshan; Kang, Wenyan; Zhu, Jin; Xu, Jianmin

    2012-01-01

    This pictorial review illustrates CT and MR imaging appearance of gastrointestinal stromal tumor (GIST) of the stomach and other lesions with similar imaging appearance. GIST of the stomach appears as well-defined enhanced masses with characteristics of subeppthial neoplasms. Majority are exophytic growth, but can also be of intra-luminal growth. GIST can growth into a large mass without gastrointestinal tract obstruction. Necrosis is often seen in GIST and results in heterogeneous enhancemen...

  10. An integrated 3-D image of cerebral blood vessels and CT view of tumor

    International Nuclear Information System (INIS)

    Suetens, P.; Baert, A.L.; Gybels, J.; Haegemans, S.; Jansen, P.; Oosterlinck, A.; Wilms, G.

    1984-01-01

    The authors developed a method that yields an integrated three-dimensional image of cerebral blood vessels and CT view of tumor. This method allows the neurosurgeon to choose any electrode trajectory that looks convenient to him, without imminent danger of causing a hemorrhage. Besides offering more safety to stereotactic interventions, this integrated 3-D image also has other applications. First, it gives a better characterization of most focal mass lesions seen by CT. Second, it allows high dose focal irradiation to be effected in such a way as to avoid arteries and veins. Third, it provides useful information for planning the strategy of open surgery

  11. SU-E-J-275: Review - Computerized PET/CT Image Analysis in the Evaluation of Tumor Response to Therapy

    International Nuclear Information System (INIS)

    Lu, W; Wang, J; Zhang, H

    2015-01-01

    Purpose: To review the literature in using computerized PET/CT image analysis for the evaluation of tumor response to therapy. Methods: We reviewed and summarized more than 100 papers that used computerized image analysis techniques for the evaluation of tumor response with PET/CT. This review mainly covered four aspects: image registration, tumor segmentation, image feature extraction, and response evaluation. Results: Although rigid image registration is straightforward, it has been shown to achieve good alignment between baseline and evaluation scans. Deformable image registration has been shown to improve the alignment when complex deformable distortions occur due to tumor shrinkage, weight loss or gain, and motion. Many semi-automatic tumor segmentation methods have been developed on PET. A comparative study revealed benefits of high levels of user interaction with simultaneous visualization of CT images and PET gradients. On CT, semi-automatic methods have been developed for only tumors that show marked difference in CT attenuation between the tumor and the surrounding normal tissues. Quite a few multi-modality segmentation methods have been shown to improve accuracy compared to single-modality algorithms. Advanced PET image features considering spatial information, such as tumor volume, tumor shape, total glycolytic volume, histogram distance, and texture features have been found more informative than the traditional SUVmax for the prediction of tumor response. Advanced CT features, including volumetric, attenuation, morphologic, structure, and texture descriptors, have also been found advantage over the traditional RECIST and WHO criteria in certain tumor types. Predictive models based on machine learning technique have been constructed for correlating selected image features to response. These models showed improved performance compared to current methods using cutoff value of a single measurement for tumor response. Conclusion: This review showed that

  12. SU-E-J-275: Review - Computerized PET/CT Image Analysis in the Evaluation of Tumor Response to Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lu, W; Wang, J; Zhang, H [University of Maryland School of Medicine, Baltimore, MD (United States)

    2015-06-15

    Purpose: To review the literature in using computerized PET/CT image analysis for the evaluation of tumor response to therapy. Methods: We reviewed and summarized more than 100 papers that used computerized image analysis techniques for the evaluation of tumor response with PET/CT. This review mainly covered four aspects: image registration, tumor segmentation, image feature extraction, and response evaluation. Results: Although rigid image registration is straightforward, it has been shown to achieve good alignment between baseline and evaluation scans. Deformable image registration has been shown to improve the alignment when complex deformable distortions occur due to tumor shrinkage, weight loss or gain, and motion. Many semi-automatic tumor segmentation methods have been developed on PET. A comparative study revealed benefits of high levels of user interaction with simultaneous visualization of CT images and PET gradients. On CT, semi-automatic methods have been developed for only tumors that show marked difference in CT attenuation between the tumor and the surrounding normal tissues. Quite a few multi-modality segmentation methods have been shown to improve accuracy compared to single-modality algorithms. Advanced PET image features considering spatial information, such as tumor volume, tumor shape, total glycolytic volume, histogram distance, and texture features have been found more informative than the traditional SUVmax for the prediction of tumor response. Advanced CT features, including volumetric, attenuation, morphologic, structure, and texture descriptors, have also been found advantage over the traditional RECIST and WHO criteria in certain tumor types. Predictive models based on machine learning technique have been constructed for correlating selected image features to response. These models showed improved performance compared to current methods using cutoff value of a single measurement for tumor response. Conclusion: This review showed that

  13. Single-level dynamic spiral CT of hepatocellular carcinoma: correlation between imaging features and tumor angiogenesis

    International Nuclear Information System (INIS)

    Chen Weixia; Min Pengqiu; Song Bin; Xiao Bangliang; Liu Yan; Wang Wendong; Chen Xian; Xu Jianying

    2001-01-01

    Objective: To investigate the correlation of the enhancement imaging features of hepatocellular carcinoma (HCC) and relevant parameters revealed by single-level dynamic spiral CT scanning with tumor microvessel counting (MVC). Methods: The study included 26 histopathologically proven HCC patients. Target-slice dynamic scanning and portal venous phase scanning were performed for all patients. The time-density curves were generated with measurement of relevant parameters including: peak value (PV) and contrast enhancement ratio (CER), and the gross enhancement morphology analyzed. Histopathological slides were carefully prepared for the standard F8RA and VEGF immunohistochemical staining and tumor microvessel counting and calculation of VEGF expression percentage of tumor cells. The enhancement imaging features of HCC lesions were correlatively studied with tumor MVC and VEGF expression. Results: Peak value of HCC lesions were 7.9 to 75.2 HU, CER were 3.8% to 36.0%. MVC were 6 to 91, and the VEGF expression percentage were 32.1% to 78.3%. The PV and CER were significantly correlated with tumor tissue MVC (r = 0.508 and 0.423, P < 0.01 and 0.05 respectively). There were no correlations between PV and CER and VEGF expression percentage. Both the patterns of time-density curve and the gross enhancement morphology of HCC lesions were also correlated with tumor MVC, and reflected the distribution characteristics of tumor microvessels within HCC lesions. A close association was found between the likelihood of intrahepatic metastasis of HCC lesions with densely enhanced pseudo capsules and the presence of rich tumor microvessels within these pseudo capsules. Conclusion: The parameters and the enhancement imaging features of HCC lesions on target-slice dynamic scanning are correlated with tumor MVC, and can reflect the distribution characteristics of tumor microvessels within HCC lesions. Dynamic spiral CT scanning is a valuable means to assess the angiogenic activity and

  14. CT and MR imaging features in phosphaturic mesenchymal tumor-mixed connective tissue: A case report.

    Science.gov (United States)

    Shi, Zhenshan; Deng, Yiqiong; Li, Xiumei; Li, Yueming; Cao, Dairong; Coossa, Vikash Sahadeo

    2018-04-01

    Phosphaturic mesenchymal tumor-mixed connective tissue (PMT-MCT) is rare and usually benign and slow-growing. The majority of these tumors is associated with sporadic tumor-induced osteomalacia (TIO) or rickets, affect middle-aged individuals and are located in the extremities. Previous imaging studies often focused on seeking the causative tumors of TIO, not on the radiological features of these tumors, especially magnetic resonance imaging (MRI) features. PMT-MCT remains a largely misdiagnosed, ignored or unknown entity by most radiologists and clinicians. In the present case report, a review of the known literature of PMT-MCT was conducted and the CT and MRI findings from three patient cases were described for diagnosing the small subcutaneous tumor. Typical MRI appearances of PMT-MCT were isointense relative to the muscles on T1-weighted imaging, and markedly hyperintense on T2-weighted imaging containing variably flow voids, with markedly heterogeneous/homogenous enhancement on post contrast T1-weighted fat-suppression imaging. Short time inversion recovery was demonstrated to be the optimal sequence in localizing the tumor.

  15. Comparison of CT during arterial portography, delayed iodine CT, and MR imaging for the preoperative evaluation of hepatic tumors

    International Nuclear Information System (INIS)

    Nelson, R.C.; Chezmar, J.L.; Sugarbaker, P.H.; Bernardino, M.E.

    1988-01-01

    Twenty-eight patients with neoplastic involvement of the liver were studied with CT during arterial portography, delayed iodine CT, and MR imaging, to determine the number, size, and location of focal hepatic lesions prior to hepatic tumor surgery. The MR pulse-sequences used included T1- and T2-weighted spin-echo (SE) sequences and inversion-recovery (IR) sequences at 0.5 T, 1.5 T, or both. Results were compared with operative and pathologic findings. The sensitivities for the detection of individual focal lesions are as follows: CT during arterial portography, delayed iodine CT, 77%, IR at 0.5 T, 74%; T1-weighted SE at 0.5 T, 69%; T2-weighted SE at 1.5 T, 55%, IR at 1.5 T, 50%; T2-weighted SE at 0.5 T, 48%, and T1-weighted SE at 1.5 T, 31%. The positive predictive values ranged from 88% to 100% for all techniques. The authors' data suggest that CT during arterial portography is a superior technique for evaluating patients prior to hepatic tumor surgery

  16. The impact of respiratory motion on tumor quantification and delineation in static PET/CT imaging

    International Nuclear Information System (INIS)

    Liu Chi; Pierce II, Larry A; Alessio, Adam M; Kinahan, Paul E

    2009-01-01

    Our aim is to investigate the impact of respiratory motion on tumor quantification and delineation in static PET/CT imaging using a population of patient respiratory traces. A total of 1295 respiratory traces acquired during whole body PET/CT imaging were classified into three types according to the qualitative shape of their signal histograms. Each trace was scaled to three diaphragm motion amplitudes (6 mm, 11 mm and 16 mm) to drive a whole body PET/CT computer simulation that was validated with a physical phantom experiment. Three lung lesions and one liver lesion were simulated with diameters of 1 cm and 2 cm. PET data were reconstructed using the OS-EM algorithm with attenuation correction using CT images at the end-expiration phase and respiratory-averaged CT. The errors of the lesion maximum standardized uptake values (SUV max ) and lesion volumes between motion-free and motion-blurred PET/CT images were measured and analyzed. For respiration with 11 mm diaphragm motion and larger quiescent period fraction, respiratory motion can cause a mean lesion SUV max underestimation of 28% and a mean lesion volume overestimation of 130% in PET/CT images with 1 cm lesions. The errors of lesion SUV max and volume are larger for patient traces with larger motion amplitudes. Smaller lesions are more sensitive to respiratory motion than larger lesions for the same motion amplitude. Patient respiratory traces with relatively larger quiescent period fraction yield results less subject to respiratory motion than traces with long-term amplitude variability. Mismatched attenuation correction due to respiratory motion can cause SUV max overestimation for lesions in the lower lung region close to the liver dome. Using respiratory-averaged CT for attenuation correction yields smaller mismatch errors than those using end-expiration CT. Respiratory motion can have a significant impact on static oncological PET/CT imaging where SUV and/or volume measurements are important. The impact

  17. 3D-CT imaging processing for qualitative and quantitative analysis of maxillofacial cysts and tumors

    International Nuclear Information System (INIS)

    Cavalcanti, Marcelo de Gusmao Paraiso; Antunes, Jose Leopoldo Ferreira

    2002-01-01

    The objective of this study was to evaluate spiral-computed tomography (3D-CT) images of 20 patients presenting with cysts and tumors in the maxillofacial complex, in order to compare the surface and volume techniques of image rendering. The qualitative and quantitative appraisal indicated that the volume technique allowed a more precise and accurate observation than the surface method. On the average, the measurements obtained by means of the 3D volume-rendering technique were 6.28% higher than those obtained by means of the surface method. The sensitivity of the 3D surface technique was lower than that of the 3D volume technique for all conditions stipulated in the diagnosis and evaluation of lesions. We concluded that the 3D-CT volume rendering technique was more reproducible and sensitive than the 3D-CT surface method, in the diagnosis, treatment planning and evaluation of maxillofacial lesions, especially those with intra-osseous involvement. (author)

  18. 3D-CT imaging processing for qualitative and quantitative analysis of maxillofacial cysts and tumors

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcanti, Marcelo de Gusmao Paraiso [Sao Paulo Univ., SP (Brazil). Faculdade de Odontologia. Dept. de Radiologia; Antunes, Jose Leopoldo Ferreira [Sao Paulo Univ., SP (Brazil). Faculdade de Odotologia. Dept. de Odontologia Social

    2002-09-01

    The objective of this study was to evaluate spiral-computed tomography (3D-CT) images of 20 patients presenting with cysts and tumors in the maxillofacial complex, in order to compare the surface and volume techniques of image rendering. The qualitative and quantitative appraisal indicated that the volume technique allowed a more precise and accurate observation than the surface method. On the average, the measurements obtained by means of the 3D volume-rendering technique were 6.28% higher than those obtained by means of the surface method. The sensitivity of the 3D surface technique was lower than that of the 3D volume technique for all conditions stipulated in the diagnosis and evaluation of lesions. We concluded that the 3D-CT volume rendering technique was more reproducible and sensitive than the 3D-CT surface method, in the diagnosis, treatment planning and evaluation of maxillofacial lesions, especially those with intra-osseous involvement. (author)

  19. CT of abdominal tumor

    International Nuclear Information System (INIS)

    Endo, Satoshi; Yamada, Kenji; Ito, Masatoshi; Ito, Hisao; Yamaura, Harutsugu

    1981-01-01

    CT findings in 33 patients who had an abdominal tumor were evaluated. CT revealed a tumor in 31 cases. The organ from which the tumor originated was correctly diagnosed in 18 patients. Whether the tumor was solid or cystic was correctly predicted in 28 patients. The diagnosis malignant or benign nature of tumor was correct, incorrect and impossible, in 23, 3, and five patiens, respectively. (Kondo, M.)

  20. New radiological examination for tumor in the internal auditory canal by combination of air CT cisternography and target imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yagishita, A.; Shiga, I.; Kanzaki, H. (Keio Univ., Tokyo (Japan). School of Medicine)

    1982-07-01

    A 56-year-old man was admitted to the hospital because of progressive right hearing disturbance and tinnitus. An x-ray film of the skull demonstrated dilatation of the right internal auditory canal. Intravcnously enhanced CT didn't reveal any tumor in the right cerebellopontine angle. An intracanalicular tumor was demonstrated by air CT cisternography with target imaging, and confirmed by surgery. This method is useful for the radiological evaluation of the intracanalicular tumors.

  1. A new radiological examination for tumor in the internal auditory canal by combination of air CT cisternography and target imaging

    International Nuclear Information System (INIS)

    Yagishita, Akira; Shiga, Itsuo; Kanzaki, Hitoshi

    1982-01-01

    A 56-year-old man was admitted to the hospital because of progressive right hearing disturbance and tinnitus. An x-ray film of the skull demonstrated dilatation of the right internal auditory canal. Intravcnously enhanced CT didn't reveal any tumor in the right cerebellopontine angle. An intracanalicular tumor was demonstrated by air CT cisternography with target imaging, and confirmed by surgery. This method is useful for the radiological evaluation of the intracanalicular tumors. (author)

  2. New radiological examination for tumor in the internal auditory canal by combination of air CT cisternography and target imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yagishita, A; Shiga, I; Kanzaki, H [Keio Univ., Tokyo (Japan). School of Medicine

    1982-07-01

    A 56-year-old man was admitted to the hospital because of progressive right hearing disturbance and tinnitus. An x-ray film of the skull demonstrated dilatation of the right internal auditory canal. Intravcnously enhanced CT didn't reveal any tumor in the right cerebellopontine angle. An intracanalicular tumor was demonstrated by air CT cisternography with target imaging, and confirmed by surgery. This method is useful for the radiological evaluation of the intracanalicular tumors.

  3. Polydopamine-coated gold nanostars for CT imaging and enhanced photothermal therapy of tumors

    Science.gov (United States)

    Li, Du; Shi, Xiangyang; Jin, Dayong

    2016-12-01

    The advancement of biocompatible nanoplatforms with dual functionalities of diagnosis and therapeutics is strongly demanded in biomedicine in recent years. In this work, we report the synthesis and characterization of polydopamine (pD)-coated gold nanostars (Au NSs) for computed tomography (CT) imaging and enhanced photothermal therapy (PTT) of tumors. Au NSs were firstly formed via a seed-mediated growth method and then stabilized with thiolated polyethyleneimine (PEI-SH), followed by deposition of pD on their surface. The formed pD-coated Au NSs (Au-PEI@pD NSs) were well characterized. We show that the Au-PEI@pD NSs are able to convert the absorbed near-infrared laser light into heat, and have strong X-ray attenuation property. Due to the co-existence of Au NSs and the pD, the light to heat conversion efficiency of the NSs can be significantly enhanced. These very interesting properties allow their uses as a powerful theranostic nanoplatform for efficient CT imaging and enhanced phtotothermal therapy of cancer cells in vitro and the xenografted tumor model in vivo. With the easy functionalization nature enabled by the coated pD shell, the developed pD-coated Au NSs may be developed as a versatile nanoplatform for targeted CT imaging and PTT of different types of cancer.

  4. CT and MR imaging in atypical teratoid/rhabdoid tumors of the central nervous system

    Energy Technology Data Exchange (ETDEWEB)

    Warmuth-Metz, Monika [University of Wuerzburg, Reference Centre for Neuroradiology of the German Society for Pediatric Hematology and Oncology (GPOH), Department of Neuroradiology, Wuerzburg (Germany); Abteilung fuer Neuroradiologie der Universitaet Wuerzburg, Wuerzburg (Germany); Bison, Brigitte [University of Wuerzburg, Reference Centre for Neuroradiology of the German Society for Pediatric Hematology and Oncology (GPOH), Department of Neuroradiology, Wuerzburg (Germany); Dannemann-Stern, Elke; Kortmann, Rolf [University of Tuebingen, Reference Centre for Radiooncology of the German Society for Pediatric Hematology and Oncology (GPOH), Department of Radiooncology, Tuebingen (Germany); Rutkowski, Stefan [University of Wuerzburg, Study Centre of the HIT-Studies of the German Society for Pediatric Hematology and Oncology (GPOH), Department of Pediatrics, Wuerzburg (Germany); Pietsch, Torsten [University of Bonn, German Reference Centre for Neuropathology, Bonn (Germany)

    2008-05-15

    Atypical teratoid/rhabdoid tumors (ATRT) are rare aggressive neoplasms of the CNS affecting predominantly very young children. We retrospectively reviewed the imaging findings of 9 CT and 32 MR examinations of the brain and spine of 33 children. Of the 33 tumors, 11 were located in the infratentorial compartment, 16 in the supratentorial compartment, 5 in both cranial compartments, and 1 in the lower thoracic spinal cord. The mean age of the children with infratentorial or infra- and supratentorial tumors was significantly lower than the mean age of the children with purely supratentorial tumors. Heterogeneity on imaging, large size and high tumor stages are striking features reflecting the aggressive nature of this histopathological entity. Although not present in the majority of children, a distinct and unusual pattern of a wavy band-like enhancement surrounding a central hypointensity was present in 12 of 32 children (38%) in whom contrast medium was used. To the best of our knowledge this is the largest number of imaging examinations of ATRTs so far reported. A rather unusual pattern of contrast enhancement may be typical of ATRTs. (orig.)

  5. CT imaging findings of neuroendocrine tumor arising from tailgut cyst: a case report

    International Nuclear Information System (INIS)

    Aydin, N.; Kara, T.; Kebapci, M.

    2012-01-01

    Full text: Introduction: We present a case of neuroendocrine tumor which is arisen from a tailgut cyst in a middle aged woman with its computed tomography (CT) imaging findings. Objective and tasks:The tailgut normally involutes by the eighth week of gestational age. If a tailgut rest proceeds, it may give rise to a tailgut cyst in the presacral space. Malign transformation of the tailgut cyst is very rare. Material and methods: A 35-year-old woman with a history of endometriosis admitted to our hospital for her routine control.An ultrasonography examination and contrast medium enhanced tomography of the abdomen and pelvis were performed. Results: CT showed multiple well-defined solid heterogen masses in presacral space. The patient underwent surgery. Pathology was reported as neuroendocrine tumor arising within tailgut cyst. Conclusion: Adenocarcinoma, neuroendocrine carcinoma, and sarcoma developing within the tailgut cyst has been reported. CT shows well-marginated presacral mass.If concurrent malignant transformation occurs, CT shows loss of margins and involvement of adjacent structures.Diagnosis of tailgut cyst is important because of it's malignant potential

  6. Incidental diagnosis of tumor thrombosis on FDG PET/CT imaging.

    Science.gov (United States)

    Erhamamci, S; Reyhan, M; Nursal, G N; Torun, N; Yapar, A F

    2015-01-01

    Clinical data are presented on patients with tumor thrombosis (TT) incidentally detected on FDG PET/CT imaging, as well as determining its prevalence and metabolic characteristics. Out of 12,500 consecutive PET/CT examinations of patients with malignancy, the PET/CT images of 15 patients with TT as an incidental finding were retrospectively investigated. A visual and semiquantitative analyses was performed on the PET/CT scans. An evaluation was made of the pattern of FDG uptake in the involved vessel as linear or focal via visual analyses. For the semiquantitative analyses, the metabolic activity was measured using SUVmax by drawing the region of interest at the site of the thrombosis and tumor (if any). The prevalence of occult TT was 0.12%. A total of 15 patients had various malignancies including renal (1 patient), liver (4), pancreas (2), stomach (1), colon (1), non-Hodgkin lymphoma (1), leiomyosarcoma (1), endometrial (1), ovarian (1), malign melanoma (1) and parotid (1). Nineteen vessels with TT were identified in 15 patients; three patients had more than one vessel. Various vessels were affected; the most common was the inferior vena cava (n=7) followed by the portal (n=5), renal (n=3), splenic (n=1), jugular (n=1), common iliac (n=1) and ovarian vein (n=1). The FDG uptake pattern was linear in 12 and focal in 3 patients. The mean SUVmax values in the TT and primary tumors were 8.40±4.56 and 13.77±6.80, respectively. Occult TT from various malignancies and locations was found incidentally in 0.12% of patients. Interesting cases with malign melanoma and parotid carcinoma and with TT in ovarian vein were first described by FDG PET/CT. Based on the linear FDG uptake pattern and high SUVmax value, PET/CT may accurately detect occult TT, help with the assessment of treatment response, contribute to correct tumor staging, and provide additional information on the survival rates of oncology patients. Copyright © 2015 Elsevier España, S.L.U. and SEMNIM. All

  7. Availability of perfluoroctylbromide (PFOB) emulsion used as agent in the liver tumor imaging of computed tomography (CT)

    International Nuclear Information System (INIS)

    Ozawa, Takachika

    1986-01-01

    We carried out a fundamental study on the availability of perfluoroctylbromide (PFOB) emulsion used as an agent in the liver tumor imaging of computed tomography (CT). For this study, we used emulsified yolk phospolipid as a surfactant for PFOB emulsion because it is generally considered to have higher safety relative to the administration to the humans. In the rabbits' liver tumor model in which VX 2 tumor cell was implanted into their livers, we observed increases in the CT values of the livers when 5 to 10 ml/kg of PFOB emulsion (20 % w/v) was administered into the vein, and also ringlike enhancement and increases in the CT values on the tumor rim when 20 ml/kg of PFOB emulsion was administered. In addition, in the chemical analysis of a gas chromatography, we also observed significant increases in the PFOB concentration on the tumor rim, compared with those of normal liver parenchyma, when 20 ml/kg of PFOB emulsion was given. In the finding of CT values in the human liver tumor by means of organ perfusion system, we recognized increases in the CT values (induced by the accumulation of PFOB emulsion) on the rim of the metastatic tumor of colon cancer. These results suggest that PFOB emulsion has certain availability as an agent for the liver tumor imaging of computed tomography (CT). (author)

  8. Automated segmentation of murine lung tumors in x-ray micro-CT images

    Science.gov (United States)

    Swee, Joshua K. Y.; Sheridan, Clare; de Bruin, Elza; Downward, Julian; Lassailly, Francois; Pizarro, Luis

    2014-03-01

    Recent years have seen micro-CT emerge as a means of providing imaging analysis in pre-clinical study, with in-vivo micro-CT having been shown to be particularly applicable to the examination of murine lung tumors. Despite this, existing studies have involved substantial human intervention during the image analysis process, with the use of fully-automated aids found to be almost non-existent. We present a new approach to automate the segmentation of murine lung tumors designed specifically for in-vivo micro-CT-based pre-clinical lung cancer studies that addresses the specific requirements of such study, as well as the limitations human-centric segmentation approaches experience when applied to such micro-CT data. Our approach consists of three distinct stages, and begins by utilizing edge enhancing and vessel enhancing non-linear anisotropic diffusion filters to extract anatomy masks (lung/vessel structure) in a pre-processing stage. Initial candidate detection is then performed through ROI reduction utilizing obtained masks and a two-step automated segmentation approach that aims to extract all disconnected objects within the ROI, and consists of Otsu thresholding, mathematical morphology and marker-driven watershed. False positive reduction is finally performed on initial candidates through random-forest-driven classification using the shape, intensity, and spatial features of candidates. We provide validation of our approach using data from an associated lung cancer study, showing favorable results both in terms of detection (sensitivity=86%, specificity=89%) and structural recovery (Dice Similarity=0.88) when compared against manual specialist annotation.

  9. Peritumoral brain edema in intracranial tumor evaluated by CT perfusion imaging

    International Nuclear Information System (INIS)

    Shi Yuxin; Xu Jianfeng

    2005-01-01

    Objective: To semi-quantitatively evaluate the cerebral perfusion in the peritumoral brain edema of cerebral tumors using CT perfusion imaging. Methods: Twenty-one patients with peritumoral brain edema (including pathologically confirmed meningiomas n=4, metastasis n=10, gliomas n=7) were examined by CT perfusion imaging. The regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV), and mean transit time (MTT) were calculated for peritumoral brain edema and the contralateralwhite matter. The rCBF and rCBV were compared between peritumoral brain edema and the contralateral white matter. The mean ratios (edema/contralateral white matter) of rCBF and rCBV were compared among the three tumors. Results: The rCBF and rCBV of peritumoral brain edema were significantly lower than those of contralateral white matter in patients with meningiomas and metastasis (rCBF: t=2.92 and 3.82, P 0.05). The mean ratios (edema/contralateralwhite matter) of rCBF and rCBV were not significantly different between meningiomas and metastasis (t=0.23 and 0.73, P>0.05), but both of them were significantly lower than those of gliomas (t=3.05 and 3.37, P<0.01, 0.005). Conclusion: The rCBF and rCBV in peritumoral brain edema were significantly lower than those of contralateral white matter in patients with meningiomas and metastasis, while almost the same with or higher than those of contralateral white matter in patients with gliomas. CT perfusion can provide quantitative information of blood flow in peritumoral brain edema, and is useful in the diagnosis and follow-up of cerebral tumors. (authors)

  10. {sup 18}F-FDG PET/CT compared to conventional imaging modalities in pediatric primary bone tumors

    Energy Technology Data Exchange (ETDEWEB)

    London, Kevin [The Children' s Hospital at Westmead, Department of Nuclear Medicine, Sydney, NSW (Australia); University of Sydney, Discipline of Paediatrics and Child Health, Sydney Medical School, Sydney, NSW (Australia); Stege, Claudia; Kaspers, Gertjan [VU Medical Centre, Divisions of Paediatric Oncology/Haematology, Amsterdam (Netherlands); Cross, Siobhan; Dalla-Pozza, Luciano [The Children' s Hospital at Westmead, Department of Oncology, Sydney (Australia); Onikul, Ella [The Children' s Hospital at Westmead, Department of Medical Imaging, Sydney (Australia); Graf, Nicole [The Children' s Hospital at Westmead, Department of Pathology, Sydney (Australia); Howman-Giles, Robert [The Children' s Hospital at Westmead, Department of Nuclear Medicine, Sydney, NSW (Australia); University of Sydney, Discipline of Imaging, Sydney Medical School, Sydney, NSW (Australia)

    2012-04-15

    F-Fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) is useful in adults with primary bone tumors. Limited published data exist in children. To compare hybrid FDG positron emission tomography/computed tomography (PET/CT) with conventional imaging (CI) modalities in detecting malignant lesions, predicting response to chemotherapy and diagnosing physeal involvement in pediatric primary bone tumors. Retrospective analysis of PET/CT and CI reports with histopathology or follow-up > 6 months as reference standard. Response parameters and physeal involvement at diagnosis were compared to histopathology. A total of 314 lesions were detected in 86 scans. Excluding lung lesions, PET/CT had higher sensitivity and specificity than CI (83%, 98% and 78%, 97%, respectively). In lung lesions, PET/CT had higher specificity than CI (96% compared to 87%) but lower sensitivity (80% compared to 93%). Higher initial SUV{sub max} and greater SUV{sub max} reduction on PET/CT after chemotherapy predicted a good response. Change in tumor size on MRI did not predict response. Both PET/CT and MRI were very sensitive but of low specificity in predicting physeal tumor involvement. PET/CT appears more accurate than CI in detecting malignant lesions in childhood primary bone tumors, excluding lung lesions. It seems better than MRI at predicting tumor response to chemotherapy. (orig.)

  11. 18F-FDG PET/CT compared to conventional imaging modalities in pediatric primary bone tumors

    International Nuclear Information System (INIS)

    London, Kevin; Stege, Claudia; Kaspers, Gertjan; Cross, Siobhan; Dalla-Pozza, Luciano; Onikul, Ella; Graf, Nicole; Howman-Giles, Robert

    2012-01-01

    F-Fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) is useful in adults with primary bone tumors. Limited published data exist in children. To compare hybrid FDG positron emission tomography/computed tomography (PET/CT) with conventional imaging (CI) modalities in detecting malignant lesions, predicting response to chemotherapy and diagnosing physeal involvement in pediatric primary bone tumors. Retrospective analysis of PET/CT and CI reports with histopathology or follow-up > 6 months as reference standard. Response parameters and physeal involvement at diagnosis were compared to histopathology. A total of 314 lesions were detected in 86 scans. Excluding lung lesions, PET/CT had higher sensitivity and specificity than CI (83%, 98% and 78%, 97%, respectively). In lung lesions, PET/CT had higher specificity than CI (96% compared to 87%) but lower sensitivity (80% compared to 93%). Higher initial SUV max and greater SUV max reduction on PET/CT after chemotherapy predicted a good response. Change in tumor size on MRI did not predict response. Both PET/CT and MRI were very sensitive but of low specificity in predicting physeal tumor involvement. PET/CT appears more accurate than CI in detecting malignant lesions in childhood primary bone tumors, excluding lung lesions. It seems better than MRI at predicting tumor response to chemotherapy. (orig.)

  12. 3D tumor measurement in cone-beam CT breast imaging

    Science.gov (United States)

    Chen, Zikuan; Ning, Ruola

    2004-05-01

    Cone-beam CT breast imaging provides a digital volume representation of a breast. With a digital breast volume, the immediate task is to extract the breast tissue information, especially for suspicious tumors, preferably in an automatic manner or with minimal user interaction. This paper reports a program for three-dimensional breast tissue analysis. It consists of volumetric segmentation (by globally thresholding), subsegmentation (connection-based separation), and volumetric component measurement (volume, surface, shape, and other geometrical specifications). A combination scheme of multi-thresholding and binary volume morphology is proposed to fast determine the surface gradients, which may be interpreted as the surface evolution (outward growth or inward shrinkage) for a tumor volume. This scheme is also used to optimize the volumetric segmentation. With a binary volume, we decompose the foreground into components according to spatial connectedness. Since this decomposition procedure is performed after volumetric segmentation, it is called subsegmentation. The subsegmentation brings the convenience for component visualization and measurement, in the whole support space, without interference from others. Upon the tumor component identification, we measure the following specifications: volume, surface area, roundness, elongation, aspect, star-shapedness, and location (centroid). A 3D morphological operation is used to extract the cluster shell and, by delineating the corresponding volume from the grayscale volume, to measure the shell stiffness. This 3D tissue measurement is demonstrated with a tumor-borne breast specimen (a surgical part).

  13. Assessment of contrast enhanced respiration managed cone-beam CT for image guided radiotherapy of intrahepatic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Nikolaj K. G., E-mail: nkyj@regionsjaelland.dk [Physics and Engineering, London Regional Cancer Program, London, Ontario N6A3K7 (Canada); Stewart, Errol [Radiology, St. Joseph' s Health Care, London, Ontario N6A 4V2 (Canada); Imaging Research Lab, Robarts Research Institute, London, Ontario N6A 5B7 (Canada); Imaging Program, Lawson Health Research Institute, London, Ontario N6C 2R5 (Canada); Lock, Michael; Fisher, Barbara [Radiation Oncology, London Regional Cancer Program, London, Ontario N6A3K7 (Canada); Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6 (Canada); Kozak, Roman [Radiology, St. Joseph' s Health Care, London, Ontario N6A 4V2 (Canada); Chen, Jeff [Physics and Engineering, London Regional Cancer Program, London, Ontario N6A3K7 (Canada); Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6 (Canada); Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1 (Canada); Lee, Ting-Yim [Radiology, St. Joseph' s Health Care, London, Ontario N6A 4V2 (Canada); Imaging Research Lab, Robarts Research Institute, London, Ontario N6A 5B7 (Canada); Imaging Program, Lawson Health Research Institute, London, Ontario N6C 2R5 (Canada); Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6 (Canada); Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1 (Canada); Wong, Eugene [Physics and Engineering, London Regional Cancer Program, London, Ontario N6A3K7 (Canada); Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6 (Canada); Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1 (Canada); Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7 (Canada)

    2014-05-15

    Purpose: Contrast enhancement and respiration management are widely used during image acquisition for radiotherapy treatment planning of liver tumors along with respiration management at the treatment unit. However, neither respiration management nor intravenous contrast is commonly used during cone-beam CT (CBCT) image acquisition for alignment prior to radiotherapy. In this study, the authors investigate the potential gains of injecting an iodinated contrast agent in combination with respiration management during CBCT acquisition for liver tumor radiotherapy. Methods: Five rabbits with implanted liver tumors were subjected to CBCT with and without motion management and contrast injection. The acquired CBCT images were registered to the planning CT to determine alignment accuracy and dosimetric impact. The authors developed a simulation tool for simulating contrast-enhanced CBCT images from dynamic contrast enhanced CT imaging (DCE-CT) to determine optimal contrast injection protocols. The tool was validated against contrast-enhanced CBCT of the rabbit subjects and was used for five human patients diagnosed with hepatocellular carcinoma. Results: In the rabbit experiment, when neither motion management nor contrast was used, tumor centroid misalignment between planning image and CBCT was 9.2 mm. This was reduced to 2.8 mm when both techniques were employed. Tumors were not visualized in clinical CBCT images of human subjects. Simulated contrast-enhanced CBCT was found to improve tumor contrast in all subjects. Different patients were found to require different contrast injections to maximize tumor contrast. Conclusions: Based on the authors’ animal study, respiration managed contrast enhanced CBCT improves IGRT significantly. Contrast enhanced CBCT benefits from patient specific tracer kinetics determined from DCE-CT.

  14. Assessment of contrast enhanced respiration managed cone-beam CT for image guided radiotherapy of intrahepatic tumors

    International Nuclear Information System (INIS)

    Jensen, Nikolaj K. G.; Stewart, Errol; Lock, Michael; Fisher, Barbara; Kozak, Roman; Chen, Jeff; Lee, Ting-Yim; Wong, Eugene

    2014-01-01

    Purpose: Contrast enhancement and respiration management are widely used during image acquisition for radiotherapy treatment planning of liver tumors along with respiration management at the treatment unit. However, neither respiration management nor intravenous contrast is commonly used during cone-beam CT (CBCT) image acquisition for alignment prior to radiotherapy. In this study, the authors investigate the potential gains of injecting an iodinated contrast agent in combination with respiration management during CBCT acquisition for liver tumor radiotherapy. Methods: Five rabbits with implanted liver tumors were subjected to CBCT with and without motion management and contrast injection. The acquired CBCT images were registered to the planning CT to determine alignment accuracy and dosimetric impact. The authors developed a simulation tool for simulating contrast-enhanced CBCT images from dynamic contrast enhanced CT imaging (DCE-CT) to determine optimal contrast injection protocols. The tool was validated against contrast-enhanced CBCT of the rabbit subjects and was used for five human patients diagnosed with hepatocellular carcinoma. Results: In the rabbit experiment, when neither motion management nor contrast was used, tumor centroid misalignment between planning image and CBCT was 9.2 mm. This was reduced to 2.8 mm when both techniques were employed. Tumors were not visualized in clinical CBCT images of human subjects. Simulated contrast-enhanced CBCT was found to improve tumor contrast in all subjects. Different patients were found to require different contrast injections to maximize tumor contrast. Conclusions: Based on the authors’ animal study, respiration managed contrast enhanced CBCT improves IGRT significantly. Contrast enhanced CBCT benefits from patient specific tracer kinetics determined from DCE-CT

  15. Graphics Processing Unit-Accelerated Nonrigid Registration of MR Images to CT Images During CT-Guided Percutaneous Liver Tumor Ablations.

    Science.gov (United States)

    Tokuda, Junichi; Plishker, William; Torabi, Meysam; Olubiyi, Olutayo I; Zaki, George; Tatli, Servet; Silverman, Stuart G; Shekher, Raj; Hata, Nobuhiko

    2015-06-01

    Accuracy and speed are essential for the intraprocedural nonrigid magnetic resonance (MR) to computed tomography (CT) image registration in the assessment of tumor margins during CT-guided liver tumor ablations. Although both accuracy and speed can be improved by limiting the registration to a region of interest (ROI), manual contouring of the ROI prolongs the registration process substantially. To achieve accurate and fast registration without the use of an ROI, we combined a nonrigid registration technique on the basis of volume subdivision with hardware acceleration using a graphics processing unit (GPU). We compared the registration accuracy and processing time of GPU-accelerated volume subdivision-based nonrigid registration technique to the conventional nonrigid B-spline registration technique. Fourteen image data sets of preprocedural MR and intraprocedural CT images for percutaneous CT-guided liver tumor ablations were obtained. Each set of images was registered using the GPU-accelerated volume subdivision technique and the B-spline technique. Manual contouring of ROI was used only for the B-spline technique. Registration accuracies (Dice similarity coefficient [DSC] and 95% Hausdorff distance [HD]) and total processing time including contouring of ROIs and computation were compared using a paired Student t test. Accuracies of the GPU-accelerated registrations and B-spline registrations, respectively, were 88.3 ± 3.7% versus 89.3 ± 4.9% (P = .41) for DSC and 13.1 ± 5.2 versus 11.4 ± 6.3 mm (P = .15) for HD. Total processing time of the GPU-accelerated registration and B-spline registration techniques was 88 ± 14 versus 557 ± 116 seconds (P processing time. The GPU-accelerated volume subdivision technique may enable the implementation of nonrigid registration into routine clinical practice. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

  16. Dual tracer functional imaging of gastroenteropancreatic neuroendocrine tumors using 68Ga-DOTA-NOC PET-CT and 18F-FDG PET-CT: competitive or complimentary?

    Science.gov (United States)

    Naswa, Niraj; Sharma, Punit; Gupta, Santosh Kumar; Karunanithi, Sellam; Reddy, Rama Mohan; Patnecha, Manish; Lata, Sneh; Kumar, Rakesh; Malhotra, Arun; Bal, Chandrasekhar

    2014-01-01

    This study aimed to compare the diagnostic performance of Ga-DOTANOC PET/CT with F-FDG PET/CT in the patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs). Data of 51 patients with definite histological diagnosis of GEP-NET who underwent both Ga-DOTA-NOC PET-CT and F-FDG PET-CT within a span of 15 days were selected for this retrospective analysis. Sensitivity, specificity, and predictive values were calculated for Ga-DOTA-NOC PET-CT and F-FDG PET-CT, and results were compared both on patientwise and regionwise analysis. Ga-DOTA-NOC PET-CT is superior to F-FDG PET-CT on patientwise analysis (P DOTA-NOC PET-CT is superior to F-FDG PET-CT only for lymph node metastases (P DOTA-NOC PET-CT detected more liver and skeletal lesions compared with F-FDG PET-CT, the difference was not statistically significant. In addition, the results of combined imaging helped in selecting candidates who would undergo the appropriate mode of treatment, whether octreotide therapy or conventional chemotherapy Ga-DOTA-NOC PET-CT seems to be superior to F-FDG PET-CT for imaging GEP-NETs. However, their role seems to be complementary because combination of Ga-DOTA-NOC PET-CT and F-FDG PET-CT in such patients helps demonstrate the total disease burden and segregate them to proper therapeutic groups.

  17. Comparison of the sensitivity and specificity of CT and MR imaging in the detection of cervical nodal tumor necrosis and extracapsular tumor spread

    International Nuclear Information System (INIS)

    Yousem, D.M.; Som, P.M.; Schjwaibold, F.; Hendrix, R.

    1991-01-01

    This paper evaluates if MR imaging can achieve the sensitivity and specificity of enhanced CT in detecting tumoral nodal necrosis (TNN) and extracapsular tumor spread (ETS). Enhanced CT scans and unenhanced and enhanced MR images were retrospectively and separately reviewed by a study-blinded radiologist. Fifty-eight lymph nodes were evaluated for TNN and ETS. Readings were given for CT, T1-weighted MR, T2-weighted MR, T1-weighted and T2-weighted MR, enhanced T1-weighted fat-suppressed MR, and T1-weighted, T2-weighted, and enhanced fat suppressed T1-weighted MR. Pathology proof was used to assess TNN; CT and used to assess ETS. Enhanced CT had the highest sensitivity for TNN. The sensitivity of unenhanced MR ranged from 33% to 50%; that of enhanced MR was 47%. All MR sequences and cT had specificities for TNN >92%. The highest accuracy of MR for TNN was the unenhanced T1-weighted and T2-weighted images alone; CT accuracy was 90%. MR sensitivity for ETS was maximal with T1-weighted images; all sequences had specificities >90%. Gadolinium-enhanced images did not improve accuracy in TNN or ETS

  18. Comparison of manual vs. automated multimodality (CT-MRI) image registration for brain tumors

    International Nuclear Information System (INIS)

    Sarkar, Abhirup; Santiago, Roberto J.; Smith, Ryan; Kassaee, Alireza

    2005-01-01

    Computed tomgoraphy-magnetic resonance imaging (CT-MRI) registrations are routinely used for target-volume delineation of brain tumors. We clinically use 2 software packages based on manual operation and 1 automated package with 2 different algorithms: chamfer matching using bony structures, and mutual information using intensity patterns. In all registration algorithms, a minimum of 3 pairs of identical anatomical and preferably noncoplanar landmarks is used on each of the 2 image sets. In manual registration, the program registers these points and links the image sets using a 3-dimensional (3D) transformation. In automated registration, the 3 landmarks are used as an initial starting point and further processing is done to complete the registration. Using our registration packages, registration of CT and MRI was performed on 10 patients. We scored the results of each registration set based on the amount of time spent, the accuracy reported by the software, and a final evaluation. We evaluated each software program by measuring the residual error between 'matched' points on the right and left globes and the posterior fossa for fused image slices. In general, manual registration showed higher misalignment between corresponding points compared to automated registration using intensity matching. This error had no directional dependence and was, most of the time, larger for a larger structure in both registration techniques. Automated algorithm based on intensity matching also gave the best results in terms of registration accuracy, irrespective of whether or not the initial landmarks were chosen carefully, when compared to that done using bone matching algorithm. Intensity-matching algorithm required the least amount of user-time and provided better accuracy

  19. Missed causative tumors in diagnosing tumor-induced osteomalacia with (18)F-FDG PET/CT: a potential pitfall of standard-field imaging.

    Science.gov (United States)

    Kaneuchi, Yoichi; Hakozaki, Michiyuki; Yamada, Hitoshi; Hasegawa, Osamu; Tajino, Takahiro; Konno, Shinichi

    2016-01-01

    We describe herein two tumor-induced osteomalacia (TIO) cases for whom the causative lesions, located in their popliteal fossa, that were not identified in the standard field of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT), which usually images only the head, trunk, and proximal parts of the extremities. A 47 years old Japanese man with multiple pathological fractures due to osteomalacia, accompanied by muscle weakness, hypophosphatemia, and an elevation of alkaline phosphatase (ALP) was referred to our hospital. A (18)F-FDG PET/CT scan was performed, but no (18)F-FDG uptake was detected in the standard field of imaging. Magnetic resonance imaging revealed a small subcutaneous tumor (1.9×1.2×0.6cm) of the left posteriomedial knee, displaying uniform enhancement on gadolinium-enhanced T1-weighted fat-suppression imaging. The tumor was resected widely and diagnosed as phosphaturic mesenchymal tumor, mixed connective tissue variant (PMTMCT). The other patient was a 31 years old Japanese woman with multiple pathological fractures, hypophosphatemia and elevated of ALP and was referred to our hospital on suspicion of TIO. Although the causative lesion was not identified in the standard field of (18)F-FDG PET/CT, (18)F-FDG uptake (SUVmax 2.9) was detected on the right knee in the additional whole-body (18)F-FDG PET/CT. Magnetic resonance imaging revealed a soft-tissue tumor (6.4×4.1×2.9cm) in the right posterior knee. Following biopsy, the tumor was marginally resected, and was pathologically diagnosed as PMTMCT. Once patients are suspected to have TIO, a whole-body nuclear imaging study such as (18)F-FDG PET/CT should be performed, in order not to miss the hidden causative tumor, especially occurring in the distal extremities.

  20. Salivary gland tumors of the parotid gland: CT and MR imaging findings with emphasis on intratumoral cystic components

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Hiroki; Watanabe, Haruo [Gifu University School of Medicine, Department of Radiology, Gifu (Japan); Kanematsu, Masayuki [Gifu University School of Medicine, Department of Radiology, Gifu (Japan); Gifu University Hospital, High-Level Imaging Diagnosis Center, Gifu (Japan); Mizuta, Keisuke; Aoki, Mitsuhiro [Gifu University School of Medicine, Department of Otolaryngology, Gifu (Japan)

    2014-09-15

    The purpose of this study was to assess computed tomography (CT) and magnetic resonance (MR) imaging findings of salivary gland tumors of the parotid gland with emphasis on intratumoral cystic components. Seventy-two histopathologically confirmed salivary gland tumors of the parotid gland (44 benign and 28 malignant), which underwent both CT and MR imaging including contrast-enhanced study, were included in this study. We retrospectively reviewed images for the presence, number, occupying rate, margin characteristics, distribution, and predominant MR signal intensity of intratumoral cystic components. The prevalence of cystic components was greater in malignant than benign tumors (79 vs. 50 %, p < 0.05). The number and occupying rate were similar between benign and malignant tumors. The irregular margins were more frequent in malignant than benign tumors (73 vs. 27 %, p < 0.01). The frequency of eccentric location was greater in benign than malignant tumors (91 vs. 55 %, p < 0.01), whereas the frequency of centric location was greater in malignant than benign tumors (32 vs. 0 %, p < 0.01). On T1-weighted images, the frequency of hyperintensity was greater in benign than malignant tumors (50 vs. 9 %, p < 0.01), whereas that of isointensity was greater in malignant than benign tumors (50 vs. 0 %, p < 0.01). Multiple logistic regression analysis showed that the absence of irregular margins of cystic components only was significantly correlated with the presence of benign salivary gland tumors (p < 0.01). Imaging features of intratumoral cystic components may help to differentiate benign from malignant tumors of the parotid salivary gland. (orig.)

  1. Imaging of lung metastasis tumor mouse model using [{sup 18}F]FDG small animal PET and CT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, June Youp; Woo, Sang Keun; Lee, Tae Sup [Korea Institute of Radiological and Medical Sciences (KIRAMS), Seoul (Korea, Republic of)] (and others)

    2007-02-15

    The purpose of this study is to image metastaic lung melanoma model with optimal pre-conditions for animal handling by using [{sup 18}F]FDG small animal PET and clinical CT. The pre-conditions for lung region tumor imaging were 16-22 h fasting and warming temperature at 30 .deg. C. Small animal PET image was obtained at 60 min postinjection of 7.4 MBq [{sup 18}F]FDG and compared pattern of [{sup 18}F]FDG uptake and glucose standard uptake value (SUVG) of lung region between Ketamine/Xylazine (Ke/Xy) and Isoflurane (Iso) anesthetized group in normal mice. Metastasis tumor mouse model to lung was established by intravenous injection of B16-F10 cells in C57BL/6 mice. In lung metastasis tumor model, [{sup 18}F]FDG image was obtained and fused with anatomical clinical CT image. Average blood glucose concentration in normal mice were 128.0 {+-} 22.87 and 86.0 {+-} 21.65 mg/dL in Ke/Xy group and Iso group, respectively. Ke/Xy group showed 1.5 fold higher blood glucose concentration than Iso group. Lung to Background ratio (L/B) in SUVG image was 8.6 {+-} 0.48 and 12.1 {+-}0.63 in Ke/Xy group and Iso group, respectively. In tumor detection in lung region, [{sup 18}F]FDG image of Iso group was better than that of Ke/Xy group, because of high L/B ratio. Metastatic tumor location in [{sup 18}F]FDG small animal PET image was confirmed by fusion image using clinical CT. Tumor imaging in small animal lung region with [{sup 18}F]FDG small animal PET should be considered pre-conditions which fasting, warming and an anesthesia during [{sup 18}F]FDG uptake. Fused imaging with small animal PET and CT image could be useful for the detection of metastatic tumor in lung region.

  2. Improved automated production of 18F-FMISO and its tumor hypoxia imaging by Micro-PET/CT

    International Nuclear Information System (INIS)

    Wang Mingwei; Zhang Yongping; Zheng Yujia; Bao Xiao; Zheng Yingjian

    2013-01-01

    Background: 1-H-1-(3-[ 18 F]fluoro-2-hydroxypropyl)-2-nitroimidazole ( 18 F-FMISO) is a specific molecular imaging probe for tumor hypoxia imaging, and its PET/CT imaging has an important clinical value for planning cancer radiotherapy target volume. Purpose: This study aimed to develop an improved, automated production of 18 F-FMISO and to perform Micro-PET/CT imaging of tumor hypoxia. Methods: Based on the labeling precursor NITTP and a simple 'one-pot' method, an upgraded Explora GN module together with Explora LC was adopted to run radiofluorination (NITTP (10 mg), MeCN (1.0 mL), 120℃, 5.0 min), hydrolysis (HCI (1.0 mol/L, 1.0 mL), 130℃, 8.0 min) and high performance liquid chromatography (HPLC) purification to produce 18 F-FMISO automatically. Moreover, Radio-HPLC and Radio-TLC were applied for the quality control, and Micro-PET/CT scanner for hypoxia imaging of SW1990 pancreatic tumor-bearing mice. Results: As results, 18 F-FMISO was obtained with the synthesis time for about 65 min, the radiochemical yield of (30±5.0)% (no decay corrected, n=20), the radiochemical purity of above 99%, the specific activity of (2.04±0.17)x10 11 Bq·μmol -1 , plus with the enhanced chemical purity. Moreover, MicroPET/CT imaging showed that 18 F-FMISO presented whole-body distribution in SW1990 tumor-bearing mice, and the optimized time point for tumor hypoxia imaging was 3 h post injection with the uptake ratios of tumor-to-muscle of 3.00±0.08. Conclusion: In sum, we developed an improved, automated production of 18 F-FMISO with high performance liquid chromatography purification, high radiochemical yield, high specific activity and high reliability , and also verified its MicroPET/CT imaging of tumor hypoxia for providing experimental reference data. (authors)

  3. DELAYED FDG-PET/CT IMAGES IN PATIENTS WITH BRAIN TUMORS - IMPACT ON VISUAL AND SEMIQUANTITATIVE ASSESSMENT

    Directory of Open Access Journals (Sweden)

    Pavel H. Bochev

    2013-01-01

    Full Text Available Background: Despite the extensive use of FDG-PET/CT its role in brain tumor assessment remains controversial mostly because of the physiologically high brain uptake which easily obscures pathological processes. The wide availability of FDG, however, maintains the interest in FDG neuro-oncological applications. Objective: to evaluate the use of a late registration at 180min in patients with brain tumors, studied with FDG-PET/CT based on visual and semiquantitative analysis. Materials and methods: 38 patients with brain neoplasms and non-tumor structural lesions underwent a selective brain 18F-FDG PET/CT at two time points at 60 and 180 minutes after administration. Visual assessment was made by two readers with interobserver agreement calculation. Region ratio comparison with three different reference regions - the contralateral one, the white matter, and the cerebellum was used as a base for semiquantitative analysis. Results: Visual analysis showed better delineation of malignant lesion on late registrations with higher inter/intraobserver agreement as compared to the early images. Semiquantitative analysis demonstrated significant differences in early and late indices of metastases and gliomas, but failed in distinguishing gliomas from metastatic lesions and benign lesions.Conclusion: Delayed brain images with FDG-PET/CT at 180 min after injection provide better tumor delineation, higher accuracy, lower interobserver variations. The use of semiquantitative indices, irrespective of the reference region used, is of limited value

  4. Development of virtual CT DICOM images of patients with tumors: application for TPS and Monte Carlo dose evaluation

    International Nuclear Information System (INIS)

    Milian, F. M.; Attili, A.; Russo, G; Marchetto, F.; Cirio, R.; Bourhaleb, F.

    2013-01-01

    A novel procedure for the generation of a realistic virtual Computed Tomography (CT) image of a patient, using the advanced Boundary RE Presentation (BREP)-based model MASH, has been implemented. This method can be used in radiotherapy assessment. It is shown that it is possible to introduce an artificial cancer, which can be modeled using mesh surfaces. The use of virtual CT images based on BREP models presents several advantages with respect to CT images of actual patients, such as automation, control and flexibility. As an example, two artificial cases, namely a brain and a prostate cancer, were created through the generation of images and tumor/organ contours. As a secondary objective, the described methodology has been used to generate input files for treatment planning system (TPS) and Monte Carlo code dose evaluation. In this paper, we consider treatment plans generated assuming a dose delivery via an active proton beam scanning performed with the INFN-IBA TPS kernel. Additionally, Monte Carlo simulations of the two treatment plans were carried out with GATE/GEANT4. The work demonstrates the feasibility of the approach based on the BREP modeling to produce virtual CT images. In conclusion, this study highlights the benefits in using digital phantom model capable of representing different anatomical structures and varying tumors across different patients. These models could be useful for assessing radiotherapy treatment planning systems (TPS) and computer simulations for the evaluation of the adsorbed dose. (author)

  5. Brain tumor and CT, 1

    International Nuclear Information System (INIS)

    Suzuki, Nobuyuki; Katada, Kazuhiro; Shinomiya, Youichi; Sano, Hirotoshi; Kanno, Tetsuo

    1981-01-01

    It is very important for a neurosurgeon to know the consistency of a brain tumor preoperatively, since the information which is of much use in indicating the likely difficulty of the operation, which operative tools should be selected, the amount of bleeding to be expected from the tumor, and so on. The authors, therefore, tried to evaluate the consistency of brain tumors preoperatively 27 cases in which the margin of the tumor was made clear with a homogeneous stain were studied concerning the relationship between the tumor consistency and the CT findings. The results are as follows: 1) A higher CT number on a plain CT indicated a harder consistency of the tumor. 2) A lesser contrast index (CT number on enhancement CT/CT number on plain CT) showed a harder consistency of the tumor. (author)

  6. Dendrimer-Stabilized Gold Nanostars as a Multifunctional Theranostic Nanoplatform for CT Imaging, Photothermal Therapy, and Gene Silencing of Tumors.

    Science.gov (United States)

    Wei, Ping; Chen, Jingwen; Hu, Yong; Li, Xin; Wang, Han; Shen, Mingwu; Shi, Xiangyang

    2016-12-01

    Development of versatile nanomaterials combining diagnostic and therapeutic functionalities within one single nanoplatform is extremely important for tumor theranostics. In this work, the authors report the synthesis of a gold nanostar (Au NS)-based theranostic platform stabilized with cyclic arginine-glycine-aspartic (Arg-Gly-Asp, RGD) peptide-modified amine-terminated generation 3 poly(amidoamine) dendrimers. The formed RGD-modified dendrimer-stabilized Au NSs (RGD-Au DSNSs) are used as a gene delivery vector to complex small interfering RNA (siRNA) for computed tomography (CT) imaging, thermal imaging, photothermal therapy (PTT), and gene therapy of tumors. The results show that the RGD-Au DSNSs are able to compact vascular endothelial growth factor siRNA and specifically deliver siRNA to cancer cells overexpressing α v β 3 integrin. Under near-infrared laser irradiation, the viability of cancer cells is only 20.2% after incubation with the RGD-Au DSNS/siRNA polyplexes, which is much lower than that of cells after single PTT or gene therapy treatment. Furthermore, in vivo results show that the RGD-Au DSNS/siRNA polyplexes enable tumor CT imaging, thermal imaging, PTT, and gene therapy after intratumoral injection. These results indicate that the developed multifunctional nanoconstruct is a promising platform for tumor imaging and combinational PTT and gene therapy. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Multimodality functional imaging of spontaneous canine tumors using 64Cu-ATSM and 18FDG PET/CT and dynamic contrast enhanced perfusion CT

    International Nuclear Information System (INIS)

    Hansen, Anders E.; Kristensen, Annemarie T.; Law, Ian; McEvoy, Fintan J.; Kjær, Andreas; Engelholm, Svend A.

    2012-01-01

    Purpose: To compare the distribution and uptake of the hypoxia tracer 64 Cu-diacetyl-bis(N 4 -methylthiosemicarbazone) ( 64 Cu-ATSM) PET/CT, FDG PET/CT and dynamic contrast enhanced perfusion CT (DCE-pCT) in spontaneous canine tumors. In addition 64 Cu-ATSM distribution over time was evaluated. Methods and materials: Nine spontaneous cancer-bearing dogs were prospectively enrolled. FDG (1 h pi.) and 64 Cu-ATSM (3 and 24 h pi.) PET/CT were performed over three consecutive days. DCE-pCT was performed on day 2. Tumor uptake of FDG and 64 Cu-ATSM was assessed semi-quantitatively and the distribution of FDG, 64 Cu-ATSM and CT perfusion parameters correlated. Results: 64 Cu-ATSM distribution on scans performed 24 h apart displayed moderate to strong correlation; however, temporal changes were observed. The spatial distribution pattern of 64 Cu-ATSM between scans was moderately to strongly positively correlated to FDG, whereas the correlation of CT perfusion parameters to FDG and to 64 Cu-ATSM yielded more varying results. Conclusions: 64 Cu-ATSM uptake was positively correlated to FDG. 64 Cu-ATSM was found to be relatively stable between PET scans performed at different time points, important temporal changes were however observed in hypo-perfused regions. These findings potentially indicate that prolonged uptake periods for 64 Cu-ATSM imaging may be needed. Although a moderate to strong correlation between 64 Cu-ATSM and FDG PET/CT is observed, the two tracers provide different biological information with an overlapping spatial distribution.

  8. Preliminary study of spectral CT imaging in the differential diagnosis of metastatic lymphadenopathy due to various tumors

    International Nuclear Information System (INIS)

    Liu Jingang; Liu Ya; Li Lixin

    2011-01-01

    Objective: To investigate the feasibility of differentiating lymph node metastases of four types of primary tumors (lymphoma, lung adenocarcinoma, lung squamous cell carcinoma and cholangiocarcinoma) using gemstone spectral imaging (GSI). Methods: Three cases with lymphoma (28 lymph node), five cases with lung adenocarcinoma (30 lymph node), four cases with lung squamous cell carcinoma (24 lymph node) and two cases with cholangiocarcinoma (10 lymph node) were evaluated by germstona spectra imaging CT scans. Imaging protocol included unenhanced conventional CT scan (120 kVp), enhanced GSI (80/140 kVp) on arterial phase and conventional CT scan (120 kVp) on portal phase. CT attenuation values of lymph nodes in the monochromatic images at Il sets of keV levels (40- 140 keV, 10 keV step) and the iodine and water contents of these lymph nodes were measured. All results were analyzed with ANOVA and t test. Results: The optimal monochromatic level was 70 keV for the optimal contrast-noise ratio (CNR) of metastatic lymphadenopathy. The CT attenuation values of metastatic lymphadenopathy were (81.36±9.81), (58.33±21.55), (56.47±10.62) and (73.57±4.43) HU, respectively, at 70 keV (F=17.29, P 0.05). The iodine contents of lymphoma, lung adenocarcinoma, lung squamous cell carcinoma and cholangiocarcinoma were (1.93±0.04), (1.16±0.15), (1.25±0.21) and (1.44±0.04) g/L, respectively. The water contents of lymphoma, lung adenocarcinoma, lung squamous cell carcinoma and cholangiocarcinoma were (1029.40±20.85), (1024.98±11.19), (1022.12±12.94) and (1030.87±10.10) g/L, respectively. Except between lung squamous cell carcinoma and lung adenocarcinoma, the differences in the iodine contents of metastatic lymphadenopathy were significant among tumors (P 0.05 ). Conclusions: Although CT spectral imaging fails to differentiate metastatic lymphadenopathy of lung adenocarcinoma and lung squamous cell carcinoma, it is also a promising method of distinguishing metastatic

  9. Multimodality functional imaging of spontaneous canine tumors using 64CU-ATSM and 18FDG PET/CT and dynamic contrast enhanced perfusion CT

    DEFF Research Database (Denmark)

    Hansen, Anders E; Kristensen, Annemarie T; Law, Ian

    2012-01-01

    To compare the distribution and uptake of the hypoxia tracer (64)Cu-diacetyl-bis(N(4)-methylthiosemicarbazone) ((64)Cu-ATSM) PET/CT, FDG PET/CT and dynamic contrast enhanced perfusion CT (DCE-pCT) in spontaneous canine tumors. In addition (64)Cu-ATSM distribution over time was evaluated.......To compare the distribution and uptake of the hypoxia tracer (64)Cu-diacetyl-bis(N(4)-methylthiosemicarbazone) ((64)Cu-ATSM) PET/CT, FDG PET/CT and dynamic contrast enhanced perfusion CT (DCE-pCT) in spontaneous canine tumors. In addition (64)Cu-ATSM distribution over time was evaluated....

  10. Dynamic-thresholding level set: a novel computer-aided volumetry method for liver tumors in hepatic CT images

    Science.gov (United States)

    Cai, Wenli; Yoshida, Hiroyuki; Harris, Gordon J.

    2007-03-01

    Measurement of the volume of focal liver tumors, called liver tumor volumetry, is indispensable for assessing the growth of tumors and for monitoring the response of tumors to oncology treatments. Traditional edge models, such as the maximum gradient and zero-crossing methods, often fail to detect the accurate boundary of a fuzzy object such as a liver tumor. As a result, the computerized volumetry based on these edge models tends to differ from manual segmentation results performed by physicians. In this study, we developed a novel computerized volumetry method for fuzzy objects, called dynamic-thresholding level set (DT level set). An optimal threshold value computed from a histogram tends to shift, relative to the theoretical threshold value obtained from a normal distribution model, toward a smaller region in the histogram. We thus designed a mobile shell structure, called a propagating shell, which is a thick region encompassing the level set front. The optimal threshold calculated from the histogram of the shell drives the level set front toward the boundary of a liver tumor. When the volume ratio between the object and the background in the shell approaches one, the optimal threshold value best fits the theoretical threshold value and the shell stops propagating. Application of the DT level set to 26 hepatic CT cases with 63 biopsy-confirmed hepatocellular carcinomas (HCCs) and metastases showed that the computer measured volumes were highly correlated with those of tumors measured manually by physicians. Our preliminary results showed that DT level set was effective and accurate in estimating the volumes of liver tumors detected in hepatic CT images.

  11. Combined approach of perioperative 18F-FDG PET/CT imaging and intraoperative 18F-FDG handheld gamma probe detection for tumor localization and verification of complete tumor resection in breast cancer

    Directory of Open Access Journals (Sweden)

    Knopp Michael V

    2007-12-01

    Full Text Available Abstract Background 18F-fluorodeoxyglucose (18F-FDG positron emission tomography/computed tomography (PET/CT has become an established method for detecting hypermetabolic sites of known and occult disease and is widely used in oncology surgical planning. Intraoperatively, it is often difficult to localize tumors and verify complete resection of tumors that have been previously detected on diagnostic PET/CT at the time of the original evaluation of the cancer patient. Therefore, we propose an innovative approach for intraoperative tumor localization and verification of complete tumor resection utilizing 18F-FDG for perioperative PET/CT imaging and intraoperative gamma probe detection. Methods Two breast cancer patients were evaluated. 18F-FDG was administered and PET/CT was acquired immediately prior to surgery. Intraoperatively, tumors were localized and resected with the assistance of a handheld gamma probe. Resected tumors were scanned with specimen PET/CT prior to pathologic processing. Shortly after the surgical procedure, patients were re-imaged with PET/CT utilizing the same preoperatively administered 18F-FDG dose. Results One patient had primary carcinoma of breast and a metastatic axillary lymph node. The second patient had a solitary metastatic liver lesion. In both cases, preoperative PET/CT verified these findings and demonstrated no additional suspicious hypermetabolic lesions. Furthermore, intraoperative gamma probe detection, specimen PET/CT, and postoperative PET/CT verified complete resection of the hypermetabolic lesions. Conclusion Immediate preoperative and postoperative PET/CT imaging, utilizing the same 18F-FDG injection dose, is feasible and image quality is acceptable. Such perioperative PET/CT imaging, along with intraoperative gamma probe detection and specimen PET/CT, can be used to verify complete tumor resection. This innovative approach demonstrates promise for assisting the oncologic surgeon in localizing and

  12. The Serum CA-125 Concentration Data Assists in Evaluating CT Imaging Information When Used to Differentiate Borderline Ovarian Tumor from Malignant Epithelial Ovarian Tumors

    International Nuclear Information System (INIS)

    Shin, Ji Eun; Choi, Hyuck Jae; Kim, Mi Hyun; Cho, Kyoung Sik

    2011-01-01

    We wanted to evaluate the diagnostic value of serum CA-125 concentration, when used in combination with the preoperative contrast-enhanced CT results, to differentiate borderline ovarian tumors (BOTs) from stage I malignant epithelial ovarian tumors (MEOTs). Ninety-eight masses (46 BOTs and 52 stage I MEOTs) from 87 consecutive patients (49 with BOTs and 38 with stage I MEOTs) who had undergone preoperative contrast-enhanced computed tomography (CT) and surgical staging were evaluated retrospectively and independently by two radiologists. The preoperative serum CA-125 concentration was measured in all patients. The utility of analyzing serum CA-125 concentration in combination with the CT results was evaluated by receiver operating characteristic (ROC) curve analysis. An irregular tumor surface and lymphadenopathy were predictive of a MEOT. ROC analysis showed that the combination of CT data and the serum CA-125 level resulted in a higher diagnostic performance than did using the CT alone for differentiating BOTs from MEOTs. The areas under the curves (AUCs) without and with the use of the serum CA-125 level data were 0.67 (95% confidence interval [CI]: 0.57-0.77) and 0.78 (95% CI: 0.68-0.85), respectively, for reader 1 (p = 0.029) and 0.71 (95% CI: 0.61-0.80) and 0.81 (95% CI: 0.72-0.89), respectively, for reader 2 (p = 0.009). The serum CA-125 concentration is of additional diagnostic value when used in conjunction with the CT imaging results for differentiating BOTs from MEOTs.

  13. [F-18]FDG imaging of head and neck tumors: comparison of hybrid PET, dedicated PET and CT

    International Nuclear Information System (INIS)

    Dresel, S.; Brinkbaeumer, K.; Schmid, R.; Poepperl, G.; Hahn, K.; Szeimies, U.

    2001-01-01

    Aim: Aim of the study was to evaluate [F-18]FDG imaging of head and neck tumors using a Hybrid-PET device of the 2nd or 3rd generation. Examinations were compared to dedicated PET and Spiral-CT. Methods: 54 patients suffering from head and neck tumors were examined using dedicated PET and Hybrid-PET after injection of 185-350 MBq [F-18]FDG. Examinations were carried out on the dedicated PET first followed by a scan on the Hybrid-PET. Dedicated PET was acquired in 3D mode, Hybrid-PET was performed in list mode using an axial filter. Reconstruction of data was performed iteratively on both, dedicated PET and Hybrid-PET. All patients received a CT scan in multislice technique. All finding have been verified by the goldstandard histology or in case of negative histology by follow up. Results: Using dedicated PET the primary or recurrent lesion was correctly diagnosed in 47/48 patients, using Hybrid-PET in 46/48 patients and using CT in 25/48 patients. Metastatic disease in cervical lymph nodes was diagnosed in 17/18 patients with dedicated PET, in 16/18 patients with Hybrid-PET and in 15/18 with CT. False positive results with regard to lymph node metastasis were seen with one patient for dedicated PET and Hybrid-PET, respectively, and with 18 patients for CT. In a total of 11 patients unknown metastastic lesions were seen with dedicated PET and with Hybrid-PET elsewhere in the body. Additional malignant disease other than the head and neck tumor was found in 4 patients. Conclusion: Using Hybrid-PET for [F-18]FDG imaging reveals a loss of sensitivity and specificity of about 1-5% as compared to dedicated PET in head and neck tumors. [F-18]FDG PET with both, dedicated PET and Hybrid-PET is superior to CT in the diagnosis of primary or recurrent lesions as well as in the assessment of lymph node involvement. (orig.) [de

  14. Thymic epithelial tumors: Comparison of CT and MR imaging findings of low-risk thymomas, high-risk thymomas, and thymic carcinomas

    International Nuclear Information System (INIS)

    Sadohara, Junko; Fujimoto, Kiminori; Mueller, Nestor L.; Kato, Seiya; Takamori, Shinzo; Ohkuma, Kazuaki; Terasaki, Hiroshi; Hayabuchi, Naofumi

    2006-01-01

    Objective: To assess the CT and magnetic resonance (MR) imaging findings of thymic epithelial tumors classified according to the current World Health Organization (WHO) histologic classification and to determine useful findings in differentiating the main subtypes. Materials and methods: Sixty patients with thymic epithelial tumor who underwent both CT and MR imaging were reviewed retrospectively. All cases were classified according to the 2004 WHO classification. The following findings were assessed in each case on both CT and MRI: size of tumor, contour, perimeter of capsule; homogeneity, presence of septum, hemorrhage, necrotic or cystic component within tumor; presence of mediastinal lymphadenopathy, pleural effusion, and great vessel invasion. These imaging characteristics of 30 low-risk thymomas (4 type A, 12 type AB, and 14 type B1), 18 high-risk thymomas (11 type B2 and seven type B3), and 12 thymic carcinomas on CT and MR imaging were compared using the chi-square test. Comparison between CT and MR findings was performed by using McNemar test. Results: On both CT and MR imaging, thymic carcinomas were more likely to have irregular contours (P < .001), necrotic or cystic component (P < .05), heterogeneous contrast-enhancement (P < .05), lymphadenopathy (P < .0001), and great vessel invasion (P < .001) than low-risk and high-risk thymomas. On MR imaging, the findings of almost complete capsule, septum, and homogenous enhancement were more commonly seen in low-risk thymomas than high-risk thymomas and thymic carcinomas (P < .05). MR imaging was superior to CT in the depiction of capsule, septum, or hemorrhage within tumor (all comparison, P < .05). Conclusion: The presence of irregular contour, necrotic or cystic component, heterogeneous enhancement, lymphadenopathy, and great vessel invasion on CT or MR imaging are strongly suggestive of thymic carcinomas. On MR imaging, the findings of contour, capsule, septum, and homogenous enhancement are helpful in

  15. CT image-guided intensity-modulated therapy for paraspinal tumors using stereotactic immobilization

    International Nuclear Information System (INIS)

    Yenice, Kamil M.; Lovelock, D. Michael; Hunt, Margie A.; Lutz, Wendell R.; Fournier-Bidoz, Nathalie; Hua, C.-H.; Yamada, Josh; Bilsky, Mark; Lee, Henry; Pfaff, Karl; Spirou, Spiridon V.; Amols, Howard I.

    2003-01-01

    Purpose: To design and implement a noninvasive stereotactic immobilization technique with daily CT image-guided positioning to treat patients with paraspinal lesions accurately and to quantify the systematic and random patient setup errors occurring with this method. Methods and Materials: A stereotactic body frame (SBF) was developed for 'rigid' immobilization of paraspinal patients. The inherent accuracy of this system for stereotactic CT-guided treatment was evaluated with phantom studies. Seven patients with thoracic and lumbar spine lesions were immobilized with the SBF and positioned for 33 treatment fractions using daily CT scans. For all 7 patients, the daily setup errors, as assessed from the daily CT scans, were corrected at each treatment fraction. A retrospective analysis was also performed to assess what the impact on patient treatment would have been without the CT-based corrections (i.e., if patient setup had been performed only with the SBF). Results: The average magnitude of systematic and random errors from uncorrected patient setups using the SBF was approximately 2 mm and 1.5 mm (1 SD), respectively. For fixed phantom targets, the system accuracy for the SBF localization and treatment was shown to be within 1 mm (1 SD) in any direction. Dose-volume histograms incorporating these uncertainties for an intensity-modulated radiotherapy plan for lumbar spine lesions were generated, and the effects on the dose-volume histograms were studied. Conclusion: We demonstrated a very accurate and precise method of patient immobilization and treatment delivery based on a noninvasive SBF and daily image guidance for paraspinal lesions. The SBF provides excellent immobilization for paraspinal targets, with setup accuracy better than 2 mm (1 SD). However, for highly conformal paraspinal treatments, uncorrected systematic and random errors of 2 mm in magnitude can result in a significantly greater (>100%) dose to the spinal cord than planned, even though the

  16. Optimization of input parameters of supra-threshold stochastic resonance image processing algorithm for the detection of abdomino-pelvic tumors on PET/CT scan

    International Nuclear Information System (INIS)

    Pandey, Anil Kumar; Saroha, Kartik; Patel, C.D.; Bal, C.S.; Kumar, Rakesh

    2016-01-01

    Administration of diuretics increases the urine output to clear radioactive urine from kidneys and bladder. Hence post-diuretic pelvic PET/CT scan enhances the probability of detection of abdomino-pelvic tumor. However, it causes discomfort in patients and has some side effects also. Application of supra threshold stochastic resonance (SSR) image processing algorithm on Pre-diuretic PET/CT scan may also increase the probability of detection of these tumors. Amount of noise and threshold are two variable parameters that effect the final image quality. This study was conducted to investigate the effect of these two variable parameters on the detection of abdomen-pelvic tumor

  17. Very low-dose adult whole-body tumor imaging with F-18 FDG PET/CT

    Science.gov (United States)

    Krol, Andrzej; Naveed, Muhammad; McGrath, Mary; Lisi, Michele; Lavalley, Cathy; Feiglin, David

    2015-03-01

    The aim of this study was to evaluate if effective radiation dose due to PET component in adult whole-body tumor imaging with time-of-flight F-18 FDG PET/CT could be significantly reduced. We retrospectively analyzed data for 10 patients with the body mass index ranging from 25 to 50. We simulated F-18 FDG dose reduction to 25% of the ACR recommended dose via reconstruction of simulated shorter acquisition time per bed position scans from the acquired list data. F-18 FDG whole-body scans were reconstructed using time-of-flight OSEM algorithm and advanced system modeling. Two groups of images were obtained: group A with a standard dose of F-18 FDG and standard reconstruction parameters and group B with simulated 25% dose and modified reconstruction parameters, respectively. Three nuclear medicine physicians blinded to the simulated activity independently reviewed the images and compared diagnostic quality of images. Based on the input from the physicians, we selected optimal modified reconstruction parameters for group B. In so obtained images, all the lesions observed in the group A were visible in the group B. The tumor SUV values were different in the group A, as compared to group B, respectively. However, no significant differences were reported in the final interpretation of the images from A and B groups. In conclusion, for a small number of patients, we have demonstrated that F-18 FDG dose reduction to 25% of the ACR recommended dose, accompanied by appropriate modification of the reconstruction parameters provided adequate diagnostic quality of PET images acquired on time-of-flight PET/CT.

  18. SU-E-I-100: Heterogeneity Studying for Primary and Lymphoma Tumors by Using Multi-Scale Image Texture Analysis with PET-CT Images

    Energy Technology Data Exchange (ETDEWEB)

    Li, Dengwang [Shandong Normal University, Jinan, Shandong Province (China); Wang, Qinfen [Shandong Normal University, Jinan, Shandong (China); Li, H; Chen, J [Shandong Cancer Hospital and Institute, Jinan, Shandong (China)

    2014-06-01

    Purpose: The purpose of this research is studying tumor heterogeneity of the primary and lymphoma by using multi-scale texture analysis with PET-CT images, where the tumor heterogeneity is expressed by texture features. Methods: Datasets were collected from 12 lung cancer patients, and both of primary and lymphoma tumors were detected with all these patients. All patients underwent whole-body 18F-FDG PET/CT scan before treatment.The regions of interest (ROI) of primary and lymphoma tumor were contoured by experienced clinical doctors. Then the ROI of primary and lymphoma tumor is extracted automatically by using Matlab software. According to the geometry size of contour structure, the images of tumor are decomposed by multi-scale method.Wavelet transform was performed on ROI structures within images by L layers sampling, and then wavelet sub-bands which have the same size of the original image are obtained. The number of sub-bands is 3L+1.The gray level co-occurrence matrix (GLCM) is calculated within different sub-bands, thenenergy, inertia, correlation and gray in-homogeneity were extracted from GLCM.Finally, heterogeneity statistical analysis was studied for primary and lymphoma tumor using the texture features. Results: Energy, inertia, correlation and gray in-homogeneity are calculated with our experiments for heterogeneity statistical analysis.Energy for primary and lymphomatumor is equal with the same patient, while gray in-homogeneity and inertia of primaryare 2.59595±0.00855, 0.6439±0.0007 respectively. Gray in-homogeneity and inertia of lymphoma are 2.60115±0.00635, 0.64435±0.00055 respectively. The experiments showed that the volume of lymphoma is smaller than primary tumor, but thegray in-homogeneity and inertia were higher than primary tumor with the same patient, and the correlation with lymphoma tumors is zero, while the correlation with primary tumor isslightly strong. Conclusion: This studying showed that there were effective heterogeneity

  19. Bone tumor imaging

    International Nuclear Information System (INIS)

    McLeod, R.A.; Berquist, T.H.

    1988-01-01

    The emphasis of this chapter is on the contribution of computed tomography (CT) and magnetic resonance imaging (MRI) to the care of patients with bone neoplasms. These modalities are emphasized because of their relative newness and not because they are considered more significant than the other more established examinations. Routine radiographs remain the most informative and essential imaging procedures for the diagnosis of bone tumors

  20. On-line cone beam CT image guidance for vocal cord tumor targeting

    International Nuclear Information System (INIS)

    Osman, Sarah O.S.; Boer, Hans C.J. de; Astreinidou, Eleftheria; Gangsaas, Anne; Heijmen, Ben J.M.; Levendag, Peter C.

    2009-01-01

    Background and purpose: We are developing a technique for highly focused vocal cord irradiation in early glottic carcinoma to optimally treat a target volume confined to a single cord. This technique, in contrast with the conventional methods, aims at sparing the healthy vocal cord. As such a technique requires sub-mm daily targeting accuracy to be effective, we investigate the accuracy achievable with on-line kV-cone beam CT (CBCT) corrections. Materials and methods: CBCT scans were obtained in 10 early glottic cancer patients in each treatment fraction. The grey value registration available in X-ray volume imaging (XVI) software (Elekta, Synergy) was applied to a volume of interest encompassing the thyroid cartilage. After application of the thus derived corrections, residue displacements with respect to the planning CT scan were measured at clearly identifiable relevant landmarks. The intra- and inter-observer variations were also measured. Results: While before correction the systematic displacements of the vocal cords were as large as 2.4 ± 3.3 mm (cranial-caudal population mean ± SD Σ), daily CBCT registration and correction reduced these values to less than 0.2 ± 0.5 mm in all directions. Random positioning errors (SD σ) were reduced to less than 1 mm. Correcting only for translations and not for rotations did not appreciably affect this accuracy. The residue random displacements partly stem from intra-observer variations (SD = 0.2-0.6 mm). Conclusion: The use of CBCT for daily image guidance in combination with standard mask fixation reduced systematic and random set-up errors of the vocal cords to <1 mm prior to the delivery of each fraction dose. Thus, this facilitates the high targeting precision required for a single vocal cord irradiation.

  1. Feasibility study of image guided radiotherapy for lung tumor using online and offline cone-beam CT setup verification

    International Nuclear Information System (INIS)

    Li Hongsheng; Li Baosheng; Lu Jie; Yin Yong; Yu Ningsha; Chen Yiru

    2009-01-01

    Objective: To investigate the feasibility of online and offline cone-beam CT(CBCT) guided radiotherapy for lung cancer. Methods: Fourteen patients with lung tumor treated by three-dimensional conformal radiotherapy were investigated. Online kV CBCT scan, image registration and setup correction were performed before and immediately after radiotherapy. CBCT online-guided correction data were used to calculate the population-based CTV-PTV margins under the condition of non-correction and correction in every fraction respectively. The numbers of initial images and the population-based CTV-PTV margins after the offline compensation of the system setup error were evaluated with the permission of 0.5 mm and 1.5 mm maximal residue error, respectively. Results: Under the condition of non-correction, the required margins for total error were 5.7 mm, 8.0 mm and 7.8 mm in the left-right (x axis), cranio-caudal (y axis) and anterior-posterior(z axis) directions, respectively. When the tumor was corrected in every fraction, the required margins for intra-fraction error were 2.4 mm, 2.4 mm and 2.3 mm in x,y and z axes, respectively. To correct the systematic setup error, 9 sets of CBCT images for 3.3 mm, 3.7 mm and 3.6 mm PTV margins, and 7 sets of CBCT images for 3.9 mm, 4.3 mm and 4.3 mm PTV margins in x,y and z axes were necessary when 0.5 mm and 1.5 mm maximal residue error were permitted respectively. Conclusions: Both of the online CBCT correction and the offline adaptive correction can markedly reduce the impact of setup error and reduce the required PTV margins accordingly. It is feasible to deliver the online and offline image guided radiation for patients with lung tumor. (authors)

  2. Net-based data transfer and automatic image fusion of metabolic (PET) and morphologic (CT/MRI) images for radiosurgical planning of brain tumors

    International Nuclear Information System (INIS)

    Baum, R.P.; Przetak, C.; Schmuecking, M.; Klener, G.; Surber, G.; Hamm, K.

    2002-01-01

    Aim: The main purpose of radiosurgery in comparison to conventional radiotherapy of brain tumors is to reach a higher radiation dose in the tumor and sparing normal brain tissue as much as possible. To reach this aim it is crucial to define the target volume extremely accurately. For this purpose, MRI and CT examinations are used for radiotherapy planning. In certain cases, however, metabolic information obtained by positron emission tomography (PET) may be useful to achieve a higher therapeutic accuracy by sparing important brain structures. This can be the case, i.e. in low grade astrocytomas for exact delineation of vital tumor as well as in differentiating scaring tissue from tumor recurrence and edema after operation. For this purpose, radiolabeled aminoacid analogues (e.g. C-11 methionine) and recently O-2-[ 18 F] Fluorethyl-L-Tyrosin (F-18 FET) have been introduced as PET tracers to detect the area of highest tumor metabolism which allows to obtain additional information as compared to FDG-PET that reflects the local glucose metabolism. In these cases, anatomical and metabolic data have to be combined with the technique of digital image fusion to exactly determine the target volume, the isodoses and the area where the highest dose has to be applied. Materials: We have set up a data transfer from the PET Center of the Zentralklinik Bad Berka with the Department of Stereotactic Radiation at the Helios Klinik Erfurt (distance approx. 25 km) to enable this kind of image fusion. PET data (ECAT EXACT 47, Siemens/CTI) are transferred to a workstation (NOVALIS) in the Dept. of Stereotactic Radiation to be co-registered with the CT or MRI data of the patient. All PET images are in DICOM format (obtained by using a HERMES computer, Nuclear Diagnostics, Sweden) and can easily be introduced into the NOVALIS workstation. The software uses the optimation of mutual information to achieve a good fusion quality. Sometimes manual corrections have to be performed to get an

  3. Generalities of anomalous CT chest non tumoral

    International Nuclear Information System (INIS)

    Dibarboure, L.

    2012-01-01

    This presentation is about the generalities of multidetector CT in the pulmonary, the diaphragmatic, the pleural and the mediastinum pathology.These techniques as well as the virtual endoscopy allow visualize volumetric thorax reconstructions, brain diseases, opacities, radiolucent images, respiratory and vascular diseases, pneumonia, embolism, AIDS stage, tuberculosis, tumors, etc

  4. FDG PET/CT imaging of desmoplastic small round cell tumor: findings at staging, during treatment and at follow-up

    Energy Technology Data Exchange (ETDEWEB)

    Ostermeier, Austin; Snyder, Scott E.; Shulkin, Barry L. [St. Jude Children' s Research Hospital, Department of Radiological Sciences, MS 220, Memphis, TN (United States); McCarville, M.B. [St. Jude Children' s Research Hospital, Department of Radiological Sciences, MS 220, Memphis, TN (United States); College of Medicine, University of Tennessee Health Science Center, Department of Radiology, Memphis, TN (United States); Navid, Fariba [St. Jude Children' s Research Hospital, Department of Oncology, Memphis, TN (United States); University of Tennessee Health Science Center, Department of Pediatrics, College of Medicine, Memphis, TN (United States)

    2015-08-15

    Desmoplastic small round cell tumor (DSRCT) is a very uncommon soft-tissue tumor of children and young adults. It has an aggressive course with generally poor survival. In general the assessment of tumor burden and response has relied upon CT or MRI. However these tumors are often metabolically active and can be evaluated using FDG PET/CT imaging. The purpose of this study was to determine the metabolic activity of desmoplastic small round cell tumors using FDG PET/CT imaging and the potential utility of FDG PET/CT in this disease. Eight patients (seven male, one female; ages 2-20 years, median 11 years) with confirmed DSRCT underwent 82 positron emission tomography/computed tomography (PET/CT) scans. PET/CT was used for initial staging (seven patients, eight scans), monitoring response to therapy (eight patients, 37 scans) and for surveillance of DSRCT recurrence (six patients, 37 scans). Each scan performed at diagnosis showed abnormally elevated uptake in the primary tumor. Five patients had abdominal pelvic involvement, and two of those also had thoracic disease. Six patients whose scans showed no abnormal sites of uptake at the end of therapy have had progression-free survivals of 2-10 years. One patient whose scan continued to show uptake during treatment died of disease 1.3 years from diagnosis. Another patient with persistent uptake remained in treatment 3 years after initial diagnosis. One surveillance scan identified recurrent disease. FDG PET/CT identified elevated metabolic activity in each patient studied. Despite our small sample size, FDG PET/CT scans appear useful for the management of patients with DSCRT. Patients whose studies become negative during or following treatment may have a prolonged remission. (orig.)

  5. Assessment of [18F]-fluoroacetate PET/CT as a tumor-imaging modality. Preclinical study in healthy volunteers and clinical evaluation in patients with liver tumor

    International Nuclear Information System (INIS)

    Takemoto, Kenji; Hatano, Etsuro; Nishii, Ryuichi

    2014-01-01

    Although [ 18 F]-FDG is a useful oncologic PET tracer, FDG uptake is known to be low in a certain type of hepatocellular carcinoma (HCC). [ 18 F]-fluoroacetate ( 18 F-FACE) is an [ 18 F] fluorinated acetate, which is known to be converted into fatty acids, incorporated in membrane and is expected to be a promising oncologic PET tracer. The aim of this study was to evaluate the usefulness of 18 F-FACE as an oncologic PET tracer in preclinical study in healthy volunteers and in patients with liver tumors. Twenty-four healthy volunteers (age 48.2 ± 12.9 years old; 15 male and 9 female) and ten patients with liver tumor (age 72.1 ± 7.0 years old; 6 male and 4 female) were included. We performed whole-body static PET/CT scan using 18 F-FACE (n=34) and 18 F-FDG (n=5 for volunteers, n=8 for patients) on each day, respectively. Qualitative analysis and quantitative analysis of tumors (5 HCCs, 1 cholangiocellular carcinoma, 4 metastatic tumors from colon cancer and P-NET) were performed using SUVmax and tumor-to-normal liver ratio (TNR). In healthy volunteers, 18 F-FACE was metabolically stable in vivo and its biodistribution was almost similar to blood pool, basically uniformly independent of age and gender during PET scan time (up to 3 h). Normal physiological uptake of 18 F-FACE at each organ including liver (SUVmean 1.8 ± 0.2) was lower than that of blood pool (SUVmean 2.3 ± 0.3) at 1 h after injection. Chronic inflammatory uptake around femur of post-operative state of femoral osteotomy and faint uptake of benign hemangioma were observed in a case of healthy volunteer. 18 F-FACE (SUVmax 2.7 ± 0.6, TNR 1.5 ± 0.4) of liver tumors was significantly lower than those of 18 F-FDG uptake (6.5 ± 4.2, 2.6 ± 1.7, respectively). In qualitative analysis, 18 F-FDG was positive in 4 tumors (3 HCCs, 1 CCC) and negative in the other 6 tumors, while 18 F-FACE was also positive in 4 tumors which were the same tumors with positive 18 F-FDG uptake. Biodistribution of 18 F-FACE was

  6. Assessment of consistency of the whole tumor and single section perfusion imaging with 256-slice spiral CT: a preliminary study

    International Nuclear Information System (INIS)

    Sun Hongliang; Xu Yanyan; Hu Yingying; Tian Yuanjiang; Wang Wu

    2014-01-01

    Objective: To determine the consistency between quantitative CT perfusion measurements of colorectal cancer obtained from single section with maximal tumor dimension and from average of whole tumor, and compare intra- and inter-observer consistency of the two analysis methods. Methods: Twenty-two patients with histologically proven colorectal cancer were examined prospectively with 256-slice CT and the whole tumor perfusion images were obtained. Perfusion parameters were obtained from region of interest (ROI) inserted in single section showing maximal tumor dimension, then from ROI inserted in all tumor-containing sections by two radiologists. Consistency between values of blood flow (BF), blood volume (BV) and time to peak (TTP) calculated by two methods was assessed. Intra-observer consistency was evaluated by comparing repeated measurements done by the same radiologist using both methods after 3 months. Perfusion measurements were done by another radiologist independently to assess inter-observer consistency of both methods. The results from different methods were compared using paired t test and Bland-Altman plot. Results: Twenty-two patients were examined successfully. The perfusion parameters BF, BV and TTP obtained by whole tumor perfusion and single-section analysis were (35.59 ± 14.59) ml · min -1 · 100 g -1 , (17.55 ±4.21) ml · 100 g -1 , (21.30 ±7.57) s and (34.64 ± 13.29)ml · min -1 · 100 g -1 , (17.61 ±6.39)ml · 100 g -1 , (19.82 ±9.01) s, respectively. No significant differences were observed between the means of the perfusion parameters (BF, BV, TTP) calculated by the two methods (t=0.218, -0.033, -0.668, P>0.05, respectively). The intra-observer 95% limits of consistency of perfusion parameters were BF -5.3% to 10.0%, BV -13.8% to 10.8%, TTP -15.0% to 12.6% with whole tumor analysis, respectively; BF -14.3% to 16.5%, BV -24.2% to 22.2%, TTP -19.0% to 16.1% with single section analysis, respectively. The inter-observer 95% limits of

  7. Imaging findings of sacral tumors

    International Nuclear Information System (INIS)

    Kim, Seung Ho; Hong, Sung Hwan; Choi, Ja Young; Koh, Sung Hye; Chung, Hye Won; Choi, Jung Ah; Kang, Heung Sik

    2003-01-01

    The various pathologic conditions detected at CT and MRI and subsumed by the term 'sacral tumor' include primary bone tumors, sacral canal tumors and metastases. Among these, metastases are much more common than primary bone tumors, of which chordoma is the most common. Although the imaging findings of sacral tumors are nonspecific, a patient's age and sex, and specific findings such as calcification or fluid-fluid levels, can help radiologists in their differential diagnosis. We describe the imaging findings of primary sacral tumors, emphasizing the MRI findings

  8. CT and MR imaging of craniopharyngioma

    Energy Technology Data Exchange (ETDEWEB)

    Tsuda, M. [Tohoku Univ. School of Medicine, Sendai (Japan). Dept. of Radiology; Takahashi, S. [Tohoku Univ. School of Medicine, Sendai (Japan). Dept. of Radiology; Higano, S. [Tohoku Univ. School of Medicine, Sendai (Japan). Dept. of Radiology; Kurihara, N. [Tohoku Univ. School of Medicine, Sendai (Japan). Dept. of Radiology; Ikeda, H. [Tohoku Univ. School of Medicine, Sendai (Japan). Dept. of Neurosurgery; Sakamoto, K. [Tohoku Univ. School of Medicine, Sendai (Japan). Dept. of Radiology

    1997-05-01

    We reviewed imaging findings of CT and MR imaging in 20 cases of surgically confirmed craniopharyngioma in an attempt to determine their relation to patterns of tumor extent. The relationship between these patterns and the frequency of preoperative CT diagnosis and MR imaging diagnosis according to the surgical diagnosis were determined. The CT technique was superior to MR imaging in the detection of calcification. The MR imaging technique was superior to CT for determining tumor extent and provided valuable information about the relationships of the tumor to surrounding structures. Thus, CT and MR imaging have complementary roles in the diagnosis of craniopharyngiomas. In cases of possible craniopharyngioma, noncontrast sagittal T1-weighted images may enable the identification of the normal pituitary, possibly leading to the correct diagnosis. (orig.)

  9. CT and MR imaging of craniopharyngioma

    International Nuclear Information System (INIS)

    Tsuda, M.; Takahashi, S.; Higano, S.; Kurihara, N.; Ikeda, H.; Sakamoto, K.

    1997-01-01

    We reviewed imaging findings of CT and MR imaging in 20 cases of surgically confirmed craniopharyngioma in an attempt to determine their relation to patterns of tumor extent. The relationship between these patterns and the frequency of preoperative CT diagnosis and MR imaging diagnosis according to the surgical diagnosis were determined. The CT technique was superior to MR imaging in the detection of calcification. The MR imaging technique was superior to CT for determining tumor extent and provided valuable information about the relationships of the tumor to surrounding structures. Thus, CT and MR imaging have complementary roles in the diagnosis of craniopharyngiomas. In cases of possible craniopharyngioma, noncontrast sagittal T1-weighted images may enable the identification of the normal pituitary, possibly leading to the correct diagnosis. (orig.)

  10. Imaging and PET - PET/CT imaging

    International Nuclear Information System (INIS)

    Von Schulthess, G.K.; Hany, Th.F.

    2008-01-01

    PET/CT has grown because the lack of anatomic landmarks in PET makes 'hardware-fusion' to anatomic cross-sectional data extremely useful. Addition of CT to PET improves specificity, but also sensitivity, and adding PET to CT adds sensitivity and specificity in tumor imaging. The synergistic advantage of adding CT is that the attenuation correction needed for PET data can also be derived from the CT data. This makes PET-CT 25-30% faster than PET alone, leading to higher patient throughput and a more comfortable examination for patients typically lasting 20 minutes or less. FDG-PET-CT appears to provide relevant information in the staging and therapy monitoring of many tumors, such as lung carcinoma, colorectal cancer, lymphoma, gynaecological cancers, melanoma and many others, with the notable exception of prostatic cancer. for this cancer, choline derivatives may possibly become useful radiopharmaceuticals. The published literature on the applications of FDG-PET-CT in oncology is still limited but several designed studies have demonstrated the benefits of PET-CT. (authors)

  11. Clinical evaluation of high-resolution CT, 1. CT diagnosis of liver tumors and its limit

    Energy Technology Data Exchange (ETDEWEB)

    Araki, T [Tokyo Univ. (Japan). Faculty of Medicine

    1980-03-01

    To estimate diagnostic accuracy of CT in liver tumors, CT diagnosis in 120 patients with primary hepatocellular carcinoma was discussed. As a result, primary hepatocellular carcinoma less than 2 cm in diameter could not be visualized by CT. Even tumors between 4 and 8 cm in diameter showed false negative caused by isodense tumors on images of 4 patients. To improve the detectability of liver tumors by CT, the higher resolution of low contrast regions on images are required. As a method to improve qualitative diagnosis of liver tumors, rapid intravenous injection of contrast medium was performed on 42 patients with liver tumors, As a result, images reflecting vascularity of tumors were obtained, and the differential diagnosis was possible to some extent by observing the movement of the contrast. Especially, cavernous hemangioma could be distinguished from hepatocellular carcinoma, because cavernous hemangioma showed specific images and could be diagnosed accurately.

  12. {sup 18}F-fluorodeoxyglucose-PET/CT to evaluate tumor, nodal disease, and gross tumor volume of oropharyngeal and oral cavity cancer: comparison with MR imaging and validation with surgical specimen

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, Oliver; Chambron-Pinho, Nicole; Sader, Rober [JW Goethe University, Department of Oromaxillofacial Surgery, Frankfurt (Germany); Middendorp, Markus [JW Goethe University, Department of Nuclear Medicine, Frankfurt (Germany); Mack, Martin; Vogl, Thomas J. [JW Goethe University, Department of Radiology, Frankfurt (Germany); Bisdas, Sotirios [Eberhard Karls University, Department of Neuroradiology, Tuebingen (Germany)

    2009-10-15

    The purpose of this paper is to evaluate the impact of adding combined {sup 18}F-PET/CT to MRI for T and N staging of the oral and oropharyngeal cancer and calculation of the gross tumor volume (GTV) having histopathology as reference standard. PET/CT and MRI were performed in 66 patients with suspected oral and oropharyngeal cancer (41 primary tumors/25 recurrent tumors) and nodal disease (114 nodes). Statistical analysis included the McNemar test, sensitivity, specificity for the diagnostic modalities as well as regression analysis, and Bland-Altman graphs for calculated tumor volumes. There was no statistically significant difference between the two modalities compared to pathological findings regarding detection of disease (P{>=}0.72). The sensitivity/specificity for tumor detection were 100/80% and 96.72/60% for MRI and PET/CT, respectively. The sensitivity/specificity for nodal metastases were 88.46/75% and 83.81/73.91% for MRI and PET/CT, respectively. In 18% of cases, the MRI-based T staging resulted in an overestimation of the pathologic tumor stage. The corresponding rate for PET/CT was 22%. Regarding the treated necks, both modalities showed 100% sensitivity for detection of the recurrent lesions. In necks with histologically N0 staging, MRI and PET/CT gave 22% and 26% false positive findings, respectively. The mean tumor volume in the pathologic specimen was 16.6{+-}18.6 ml, the mean volume derived by the MR imaging was 17.6{+-}19.1 ml while the estimated by PET/CT volume was 18.8{+-}18.1 ml (P{<=}0.007 between the three methods). The Bland-Altman analysis showed a better agreement between PET/CT and MRI. The diagnostic performance of FDG-PET/CT in the local staging of oral cancer is not superior to MRI. (orig.)

  13. 18F-fluorodeoxyglucose-PET/CT to evaluate tumor, nodal disease, and gross tumor volume of oropharyngeal and oral cavity cancer: comparison with MR imaging and validation with surgical specimen

    International Nuclear Information System (INIS)

    Seitz, Oliver; Chambron-Pinho, Nicole; Sader, Rober; Middendorp, Markus; Mack, Martin; Vogl, Thomas J.; Bisdas, Sotirios

    2009-01-01

    The purpose of this paper is to evaluate the impact of adding combined 18 F-PET/CT to MRI for T and N staging of the oral and oropharyngeal cancer and calculation of the gross tumor volume (GTV) having histopathology as reference standard. PET/CT and MRI were performed in 66 patients with suspected oral and oropharyngeal cancer (41 primary tumors/25 recurrent tumors) and nodal disease (114 nodes). Statistical analysis included the McNemar test, sensitivity, specificity for the diagnostic modalities as well as regression analysis, and Bland-Altman graphs for calculated tumor volumes. There was no statistically significant difference between the two modalities compared to pathological findings regarding detection of disease (P≥0.72). The sensitivity/specificity for tumor detection were 100/80% and 96.72/60% for MRI and PET/CT, respectively. The sensitivity/specificity for nodal metastases were 88.46/75% and 83.81/73.91% for MRI and PET/CT, respectively. In 18% of cases, the MRI-based T staging resulted in an overestimation of the pathologic tumor stage. The corresponding rate for PET/CT was 22%. Regarding the treated necks, both modalities showed 100% sensitivity for detection of the recurrent lesions. In necks with histologically N0 staging, MRI and PET/CT gave 22% and 26% false positive findings, respectively. The mean tumor volume in the pathologic specimen was 16.6±18.6 ml, the mean volume derived by the MR imaging was 17.6±19.1 ml while the estimated by PET/CT volume was 18.8±18.1 ml (P≤0.007 between the three methods). The Bland-Altman analysis showed a better agreement between PET/CT and MRI. The diagnostic performance of FDG-PET/CT in the local staging of oral cancer is not superior to MRI. (orig.)

  14. In vivo tumor-targeted dual-modal fluorescence/CT imaging using a nanoprobe co-loaded with an aggregation-induced emission dye and gold nanoparticles.

    Science.gov (United States)

    Zhang, Jimei; Li, Chan; Zhang, Xu; Huo, Shuaidong; Jin, Shubin; An, Fei-Fei; Wang, Xiaodan; Xue, Xiangdong; Okeke, C I; Duan, Guiyun; Guo, Fengguang; Zhang, Xiaohong; Hao, Jifu; Wang, Paul C; Zhang, Jinchao; Liang, Xing-Jie

    2015-02-01

    As an intensely studied computed tomography (CT) contrast agent, gold nanoparticle has been suggested to be combined with fluorescence imaging modality to offset the low sensitivity of CT. However, the strong quenching of gold nanoparticle on fluorescent dyes requires complicated design and shielding to overcome. Herein, we report a unique nanoprobe (M-NPAPF-Au) co-loading an aggregation-induced emission (AIE) red dye and gold nanoparticles into DSPE-PEG(2000) micelles for dual-modal fluorescence/CT imaging. The nanoprobe was prepared based on a facile method of "one-pot ultrasonic emulsification". Surprisingly, in the micelles system, fluorescence dye (NPAPF) efficiently overcame the strong fluorescence quenching of shielding-free gold nanoparticles and retained the crucial AIE feature. In vivo studies demonstrated the nanoprobe had superior tumor-targeting ability, excellent fluorescence and CT imaging effects. The totality of present studies clearly indicates the significant potential application of M-NPAPF-Au as a dual-modal non-invasive fluorescence/X-ray CT nanoprobe for in vivo tumor-targeted imaging and diagnosis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Pancreatic gross tumor volume contouring on computed tomography (CT) compared with magnetic resonance imaging (MRI): Results of an international contouring conference.

    Science.gov (United States)

    Hall, William A; Heerkens, Hanne D; Paulson, Eric S; Meijer, Gert J; Kotte, Alexis N; Knechtges, Paul; Parikh, Parag J; Bassetti, Michael F; Lee, Percy; Aitken, Katharine L; Palta, Manisha; Myrehaug, Sten; Koay, Eugene J; Portelance, Lorraine; Ben-Josef, Edgar; Erickson, Beth A

    Accurate identification of the gross tumor volume (GTV) in pancreatic adenocarcinoma is challenging. We sought to understand differences in GTV delineation using pancreatic computed tomography (CT) compared with magnetic resonance imaging (MRI). Twelve attending radiation oncologists were convened for an international contouring symposium. All participants had a clinical and research interest in pancreatic adenocarcinoma. CT and MRI scans from 3 pancreatic cases were used for contouring. CT and MRI GTVs were analyzed and compared. Interobserver variability was compared using Dice's similarity coefficient (DSC), Hausdorff distances, and Jaccard indices. Mann-Whitney tests were used to check for significant differences. Consensus contours on CT and MRI scans and constructed count maps were used to visualize the agreement. Agreement regarding the optimal method to determine GTV definition using MRI was reached. Six contour sets (3 from CT and 3 from MRI) were obtained and compared for each observer, totaling 72 contour sets. The mean volume of contours on CT was significantly larger at 57.48 mL compared with a mean of 45.76 mL on MRI, P = .011. The standard deviation obtained from the CT contours was significantly larger than the standard deviation from the MRI contours (P = .027). The mean DSC was 0.73 for the CT and 0.72 for the MRI (P = .889). The conformity index measurement was similar for CT and MRI (P = .58). Count maps were created to highlight differences in the contours from CT and MRI. Using MRI as a primary image set to define a pancreatic adenocarcinoma GTV resulted in smaller contours compared with CT. No differences in DSC or the conformity index were seen between MRI and CT. A stepwise method is recommended as an approach to contour a pancreatic GTV using MRI. Copyright © 2017 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

  16. Biplane CT in sellar and parasellar tumors, (2)

    International Nuclear Information System (INIS)

    Sadamoto, Kazuhiko; Sakaki, Saburo; Matsuoka, Kenzo; Goishi, Junji; Sokabe, Takashi.

    1980-01-01

    Biplane CT images of 30 cases of sellar and parasellar tumors were studied. All 3 cases of meningioma were discovered by biplane CT (the diagnostic rate, 100%). As biplane CT could exclude partial volume effects, biplane CT images could demonstrate a fine structure and the position of parasellar or skull-base meningioma. As features of craniopharyngioma visualized on biplane CT images were variable, 7 of 9 cases of craniopharyngioma were detected by biplane CT (the diagnostic rate, 80%). When contrast enhancement on biplane CT images was marked, sometimes differencial diagnosis of craniopharyngioma and other suprasellar tumors was difficult. In all 18 cases of chromophobe adenoma, biplane CT images successfully demonstrated the location and extension of the tumors including cystic tumor (the diagnostic rate, 100%). In addition, 2 cases of giant aneurysm were presented in this study as examples of the differential diagnosis of pituitary and supraseller tumors. Biplane CT images showed mainly the location and the size of aneurysm as a mass lesion: therefore, cerebral angiography including vertebral arteriography was necessary for making an exact diagnosis of aneurysm. (Tsunoda, M)

  17. Molecular imaging of neuroendocrine tumors using {sup 68}Ga-labeled peptides (Somatostatin receptor PET/CT); Molekulare Bildgebung neuroendokriner Tumoren mit {sup 68}Ga-markierten Peptiden (Somatostatinrezeptor-PET/CT)

    Energy Technology Data Exchange (ETDEWEB)

    Baum, R.P.; Prasad, V. [Zentralklinik Bad Berka GmbH (Germany). Klinik fuer Nuklearmedizin/PET-Zentrum; Hoersch, D. [Zentralklinik Bad Berka GmbH (Germany). Klinik fuer Innere Medizin, Gastroenterologie, Onkologie, Endokrionologie

    2009-06-15

    Receptor PET/CT using {sup 68}Ga-labeled somatostatin analogues (DOTA-NOC, DOTA-TOC or DOTA-TATE) enables the highly sensitive molecular imaging of neuroendocrine tumors (NETs) based on the expression of somatostatin receptors and even the detection of receptor subtypes. Our experience after more than 3000 studies shows that receptor PET/CT has a significantly higher tumor detection rate than conventional scintigraphy (even in SPECT/CT technique), and that tumor lesions can be very accurately localized. By calculating standardized uptake values (SUV) - which are reproducible and investigator-independent - patients can be selected for peptide receptor radiotherapy and also the course after therapy can be controlled. Receptor-PET/CT is the most sensitive imaging modality for the detection of unknown primary tumors (CUP syndrome), which is especially true for the detection of neuroendocrine tumors of the pancreas and small bowel; whole-body staging (''one stop shop'') as well as restaging and selection of patients for peptide receptor radiotherapy can be performed using a patient-friendly procedure (examination finished within one hour) exposing the patient to less radiation than whole-body CT scanning. The {sup 68}Ge/{sup 68}Ga generator has proved very reliable over the years - even in a hospital environment. The effective costs for {sup 68}Ga labeled somatostatin analogues might be less than for scintigraphic agents, provided a certain number of studies per year are performed. The development of new tumor-specific peptides as well as of other DOTA- or NOTA-coupled radiopharmaceuticals opens a new avenue into the future: finally, the {sup 68}Ga generator could play a similar important role for PET/CT as did the {sup 99m}Tc-Generator for conventional gamma camera imaging over the last decades. (orig.)

  18. Serial megavoltage CT imaging during external beam radiotherapy for non-small-cell lung cancer: Observations on tumor regression during treatment

    International Nuclear Information System (INIS)

    Kupelian, Patrick A.; Ramsey, Chester; Meeks, Sanford L.; Willoughby, Twyla R.; Forbes, Alan; Wagner, Thomas H.; Langen, Katja M.

    2005-01-01

    Purpose: The ability to obtain soft-tissue imaging in the treatment room, such as with megavoltage CT imaging, enables the observation of tumor regression during a course of external beam radiation therapy. In this current study, we report on the most extensive study looking at the rate of regression of non-small-cell lung cancers during a course of external beam radiotherapy by analyzing serial megavoltage CT images obtained on 10 patients. Methods and Materials: The analysis is performed on 10 patients treated with the Helical Tomotherapy Hi*Art device. All 10 patients had non-small-cell lung cancer. A total of 274 megavoltage CT sets were obtained on the 10 patients (average, 27 scans per patient; range, 9-35). All patients had at least a scan at beginning and at the end of treatment. The frequency of scanning was determined by the treating physician. The treatment was subsequently delivered with the Tomotherapy Hi*Art system. The gross tumor volumes (GTVs) were later contoured on each megavoltage CT scan, and tumor volumes were calculated. Although some patients were treated to draining nodal areas in addition to the primary tumor, only the primary GTVs were tracked. Response to treatment was quantified by the relative decrease in tumor volume over time, i.e., elapsed days from the first day of therapy. The individual GTVs ranged from 5.9 to 737.2 cc in volume at the start of treatment. In 6 of the 10 patients, dose recalculations were also performed to document potential variations in delivered doses within the tumors. The megavoltage CT scans were used, and the planned treatment was recalculated on the daily images. The hypothesis was that dose deposited in the target would increase throughout the course of radiotherapy because of tumor shrinkage and subsequent decreasing attenuation. Specifically, the dose received by 95% of the GTV (D 95 ) was monitored over time for each of the 6 patients treated at M.D. Anderson Cancer Center Orlando. Results: Regression

  19. Is There an Additional Value of 11C-Choline PET-CT to T2-weighted MRI Images in the Localization of Intraprostatic Tumor Nodules?

    International Nuclear Information System (INIS)

    Van den Bergh, Laura; Koole, Michel; Isebaert, Sofie; Joniau, Steven; Deroose, Christophe M.; Oyen, Raymond; Lerut, Evelyne; Budiharto, Tom; Mottaghy, Felix; Bormans, Guy; Van Poppel, Hendrik; Haustermans, Karin

    2012-01-01

    Purpose: To investigate the additional value of 11 C-choline positron emission tomography (PET)-computed tomography (CT) to T2-weighted (T2w) magnetic resonance imaging (MRI) for localization of intraprostatic tumor nodules. Methods and Materials: Forty-nine prostate cancer patients underwent T2w MRI and 11 C-choline PET-CT before radical prostatectomy and extended lymphadenectomy. Tumor regions were outlined on the whole-mount histopathology sections and on the T2w MR images. Tumor localization was recorded in the basal, middle, and apical part of the prostate by means of an octant grid. To analyze 11 C-choline PET-CT images, the same grid was used to calculate the standardized uptake values (SUV) per octant, after rigid registration with the T2w MR images for anatomic reference. Results: In total, 1,176 octants were analyzed. Sensitivity, specificity, and accuracy of T2w MRI were 33.5%, 94.6%, and 70.2%, respectively. For 11 C-choline PET-CT, the mean SUV max of malignant octants was significantly higher than the mean SUV max of benign octants (3.69 ± 1.29 vs. 3.06 ± 0.97, p mean values (2.39 ± 0.77 vs. 1.94 ± 0.61, p mean and absolute tumor volume (Spearman r = 0.3003, p = 0.0362). No correlation was found between SUVs and prostate-specific antigen, T-stage or Gleason score. The highest accuracy (61.1%) was obtained with a SUV max cutoff of 2.70, resulting in a sensitivity of 77.4% and a specificity of 44.9%. When both modalities were combined (PET-CT or MRI positive), sensitivity levels increased as a function of SUV max but at the cost of specificity. When only considering suspect octants on 11 C-choline PET-CT (SUV max ≥ 2.70) and T2w MRI, 84.7% of these segments were in agreement with the gold standard, compared with 80.5% for T2w MRI alone. Conclusions: The additional value of 11 C-choline PET-CT next to T2w MRI in detecting tumor nodules within the prostate is limited.

  20. A contrast enhancement and scanning techniques for CT angiography of head and neck. One phase injection method for simultaneous imaging of vessels and tumor

    International Nuclear Information System (INIS)

    Morita, Yasuhiko; Indo, Hiroko; Noikura, Takenori

    1999-01-01

    We report on a method of CT-Angiography useful for examining lesion of the head and neck using three-dimensional images and measured CT value. This study focused on some of the important blood vessels in the head and neck. The aim of this method was to obtain high-contrast enhancement for both vessels and tumors at same time. A total amount of 100 ml nonionic contrast media (Omnipaque 240, 240 mg iodine per milliliter, Daiichi seiyaku, Tokyo, Japan) was injected intravenously with a flow of 1.5 ml/sec. Spiral scans, 24 rotations with 24 seconds, were started at a time when remaining amount of contrast media had become 30 to 20 ml. All CT scans were performed using double speed spiral scan technique with a slice thickness of 2 to 3 mm and table speeds from 3 to 5 mm/rotation. The patients populations consisted of 9 men and 6 women who ranged in age from 37 to 85 years. Sixteen CT-angiography were performed according to this method. Mean CT values of major blood vessels were measured in order to find out threshold at the level of submandibular gland in 13 examinations for 12 subjects. Important vessels like the common, internal, and the external artery, internal and external jugular vein were clearly visible in all subjects. Three dimensional images of these vessels could also be reconstructed for 15 of the subjects. Mean CT values were 211 Hounsfield units (HU) and 209 HU for the right and left internal carotid artery, respectively, and 204 HU and 206 HU for the right and left external carotid artery, respectively. Mean CT values for right and left internal jugular vein were 195 HU and 194 HU respectively. Measured CT values at each important blood vessels showed this method could yields acceptable enhancements. Good enhancement effect of tumor and blood vessels in the same scan seems to be mutually incompatible. One very important trade-off is the early enhancement effect at blood vessels versus the late enhancement effect at tumors. The other important trade

  1. Diffusion-weighted MR imaging vs. multi-detector row CT: Direct comparison of capability for assessment of management needs for anterior mediastinal solitary tumors

    International Nuclear Information System (INIS)

    Seki, Shinichiro; Koyama, Hisanobu; Ohno, Yoshiharu; Nishio, Mizuho; Takenaka, Daisuke; Maniwa, Yoshimasa; Itoh, Tomoo; Nishimura, Yoshihiro; Sugimura, Kazuro

    2014-01-01

    Purpose: To evaluate and compare the capability of diffusion-weighted MR imaging (DWI) and CT for assessment of management needs for anterior mediastinal solitary tumors. Materials and methods: Thirty-five patients with pathologically confirmed anterior mediastinal tumors were enrolled. The tumors were divided into two groups according to need for management: tumors not needing further intervention or treatment (group A; thymoma type A, AB and B1) and tumors needing further intervention and treatment (group B; other thymoma types and malignancies). The apparent diffusion coefficient (ADC) of each tumor was measured, and probabilities of malignancy and need for further intervention and treatment were visually assessed on CT. The differences in ADCs between group A and B and between malignancies and thymomas in group B were evaluated with the Mann–Whitney's U-test. Feasible threshold values for differentiation of group B from group A and distinguishing malignancies from thymomas assessed as group B were determined by the ROC-based positive test, and McNemar's test was used for comparing diagnostic capabilities of DWI with those of CT. Results: ADCs for the two groups were significantly different (p < 0.001). Application of the threshold value for differentiation of group B from A showed no significant difference (p > 0.05). Application of the feasible threshold value for distinguishing malignant from thymomas assessed as group B showed that specificity (76.9%) and accuracy (85.2%) of DWI were significantly better than those of visual score (p < 0.05). Conclusion: DWI has useful potential for the assessment of management needs for anterior mediastinum solitary tumors as well as CT

  2. CT of portal vein tumor thrombosis. Usefulness of dynamic CT

    Energy Technology Data Exchange (ETDEWEB)

    Takemoto, Kazumasa; Inoue, Yuichi; Tanaka, Masahiro; Nemoto, Yutaka; Nakamura, Kenji [Osaka City Univ. (Japan). Faculty of Medicine

    1983-08-01

    We evaluated CT findings of portal vein tumor thrombosis in 16 hepatomas by plain, contrast and dynamic CT. Plain and contrast CT findings were an enlargement of the portal vein (81%), intraluminal low density area (63%). Dynamic CT enhanced the diagnostic capability of the tumor thrombus as a relatively low density area because of the marked enhancement of the portal vein. In addition, dynamic CT newly demonstrated hyperdense peripheral ring (35%) and arterio portal shunt (35%). It is advisable to select the scan level to include the portal vein when dynamic CT is performed in the patient of hepatocellular carcinoma.

  3. Accuracy and inter-observer variability of 3D versus 4D cone-beam CT based image-guidance in SBRT for lung tumors

    International Nuclear Information System (INIS)

    Sweeney, Reinhart A; Seubert, Benedikt; Stark, Silke; Homann, Vanessa; Müller, Gerd; Flentje, Michael; Guckenberger, Matthias

    2012-01-01

    To analyze the accuracy and inter-observer variability of image-guidance (IG) using 3D or 4D cone-beam CT (CBCT) technology in stereotactic body radiotherapy (SBRT) for lung tumors. Twenty-one consecutive patients treated with image-guided SBRT for primary and secondary lung tumors were basis for this study. A respiration correlated 4D-CT and planning contours served as reference for all IG techniques. Three IG techniques were performed independently by three radiation oncologists (ROs) and three radiotherapy technicians (RTTs). Image-guidance using respiration correlated 4D-CBCT (IG-4D) with automatic registration of the planning 4D-CT and the verification 4D-CBCT was considered gold-standard. Results were compared with two IG techniques using 3D-CBCT: 1) manual registration of the planning internal target volume (ITV) contour and the motion blurred tumor in the 3D-CBCT (IG-ITV); 2) automatic registration of the planning reference CT image and the verification 3D-CBCT (IG-3D). Image quality of 3D-CBCT and 4D-CBCT images was scored on a scale of 1–3, with 1 being best and 3 being worst quality for visual verification of the IGRT results. Image quality was scored significantly worse for 3D-CBCT compared to 4D-CBCT: the worst score of 3 was given in 19 % and 7.1 % observations, respectively. Significant differences in target localization were observed between 4D-CBCT and 3D-CBCT based IG: compared to the reference of IG-4D, tumor positions differed by 1.9 mm ± 0.9 mm (3D vector) on average using IG-ITV and by 3.6 mm ± 3.2 mm using IG-3D; results of IG-ITV were significantly closer to the reference IG-4D compared to IG-3D. Differences between the 4D-CBCT and 3D-CBCT techniques increased significantly with larger motion amplitude of the tumor; analogously, differences increased with worse 3D-CBCT image quality scores. Inter-observer variability was largest in SI direction and was significantly larger in IG using 3D-CBCT compared to 4D-CBCT: 0.6 mm versus 1.5 mm

  4. Primary cardiac and pericardial tumors, imaging approach

    Energy Technology Data Exchange (ETDEWEB)

    Yu-Qing Liu, M D [Chinese Academy of Medical Sciences, Beijing, BJ (China). Dept. of Radiology, Fu Wai Hospital and Cardiovascular Inst.

    1996-12-31

    The incidence of cardiac tumor and its classification was discussed. Imaging study i.e. conventional radiology, echocardiagoaphy (echo), magnetic resonance imaging (MRI), angiography and computed tomography (CT) used also discussed briefly. (8 refs.).

  5. Primary cardiac and pericardial tumors, imaging approach

    International Nuclear Information System (INIS)

    Yu-Qing Liu, M.D.

    1995-01-01

    The incidence of cardiac tumor and its classification was discussed. Imaging study i.e. conventional radiology, echocardiagoaphy (echo), magnetic resonance imaging (MRI), angiography and computed tomography (CT) used also discussed briefly. (8 refs.)

  6. Response evaluation of giant-cell tumor of bone treated by denosumab: Histogram and texture analysis of CT images.

    Science.gov (United States)

    Yi, Jisook; Lee, Young Han; Kim, Sang Kyum; Kim, Seung Hyun; Song, Ho-Taek; Shin, Kyoo-Ho; Suh, Jin-Suck

    2018-05-01

    This study aimed to compare computed tomography (CT) features, including tumor size and textural and histogram measurements, of giant-cell tumors of bone (GCTBs) before and after denosumab treatment and determine their applicability in monitoring GCTB response to denosumab treatment. This retrospective study included eight patients (male, 3; female, 5; mean age, 33.4 years) diagnosed with GCTB, who had received treatment by denosumab and had undergone pre- and post-treatment non-contrast CT between January 2010 and December 2016. This study was approved by the institutional review board. Pre- and post-treatment size, histogram, and textural parameters of GCTBs were compared by the Wilcoxon signed-rank test. Pathological findings of five patients who underwent surgery after denosumab treatment were evaluated for assessment of treatment response. Relative to the baseline values, the tumor size had decreased, while the mean attenuation, standard deviation, entropy (all, P = 0.017), and skewness (P = 0.036) of the GCTBs had significantly increased post-treatment. Although the difference was statistically insignificant, the tumors also exhibited increased kurtosis, contrast, and inverse difference moment (P = 0.123, 0.327, and 0.575, respectively) post-treatment. Histologic findings revealed new bone formation and complete depletion or decrease in the number of osteoclast-like giant cells. The histogram and textural parameters of GCTBs changed significantly after denosumab treatment. Knowledge of the tendency towards increased mean attenuation and heterogeneity but increased local homogeneity in post-treatment CT histogram and textural features of GCTBs might aid in treatment planning and tumor response evaluation during denosumab treatment. Copyright © 2018. Published by Elsevier B.V.

  7. Comparison of applied dose and image quality in staging CT of neuroendocrine tumor patients using standard filtered back projection and adaptive statistical iterative reconstruction

    International Nuclear Information System (INIS)

    Böning, G.; Schäfer, M.; Grupp, U.; Kaul, D.; Kahn, J.; Pavel, M.; Maurer, M.; Denecke, T.; Hamm, B.; Streitparth, F.

    2015-01-01

    Highlights: • Iterative reconstruction (IR) in staging CT provides equal objective image quality compared to filtered back projection (FBP). • IR delivers excellent subjective quality and reduces effective dose compared to FBP. • In patients with neuroendocrine tumor (NET) or may other hypervascular abdominal tumors IR can be used without scarifying diagnostic confidence. - Abstract: Objective: To investigate whether dose reduction via adaptive statistical iterative reconstruction (ASIR) affects image quality and diagnostic accuracy in neuroendocrine tumor (NET) staging. Methods: A total of 28 NET patients were enrolled in the study. Inclusion criteria were histologically proven NET and visible tumor in abdominal computed tomography (CT). In an intraindividual study design, the patients underwent a baseline CT (filtered back projection, FBP) and follow-up CT (ASIR 40%) using matched scan parameters. Image quality was assessed subjectively using a 5-grade scoring system and objectively by determining signal-to-noise ratio (SNR) and contrast-to-noise ratios (CNRs). Applied volume computed tomography dose index (CTDI vol ) of each scan was taken from the dose report. Results: ASIR 40% significantly reduced CTDI vol (10.17 ± 3.06 mGy [FBP], 6.34 ± 2.25 mGy [ASIR] (p < 0.001) by 37.6% and significantly increased CNRs (complete tumor-to-liver, 2.76 ± 1.87 [FBP], 3.2 ± 2.32 [ASIR]) (p < 0.05) (complete tumor-to-muscle, 2.74 ± 2.67 [FBP], 4.31 ± 4.61 [ASIR]) (p < 0.05) compared to FBP. Subjective scoring revealed no significant changes for diagnostic confidence (5.0 ± 0 [FBP], 5.0 ± 0 [ASIR]), visibility of suspicious lesion (4.8 ± 0.5 [FBP], 4.8 ± 0.5 [ASIR]) and artifacts (5.0 ± 0 [FBP], 5.0 ± 0 [ASIR]). ASIR 40% significantly decreased scores for noise (4.3 ± 0.6 [FBP], 4.0 ± 0.8 [ASIR]) (p < 0.05), contrast (4.4 ± 0.6 [FBP], 4.1 ± 0.8 [ASIR]) (p < 0.001) and visibility of small structures (4.5 ± 0.7 [FBP], 4.3 ± 0.8 [ASIR]) (p < 0

  8. Comparison of applied dose and image quality in staging CT of neuroendocrine tumor patients using standard filtered back projection and adaptive statistical iterative reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Böning, G., E-mail: georg.boening@charite.de [Department of Radiology, Charité, Humboldt-University Medical School, Charitéplatz 1, 10117 Berlin (Germany); Schäfer, M.; Grupp, U. [Department of Radiology, Charité, Humboldt-University Medical School, Charitéplatz 1, 10117 Berlin (Germany); Kaul, D. [Department of Radiation Oncology, Charité, Humboldt-University Medical School, Charitéplatz 1, 10117 Berlin (Germany); Kahn, J. [Department of Radiology, Charité, Humboldt-University Medical School, Charitéplatz 1, 10117 Berlin (Germany); Pavel, M. [Department of Gastroenterology, Charité, Humboldt-University Medical School, Charitéplatz 1, 10117 Berlin (Germany); Maurer, M.; Denecke, T.; Hamm, B.; Streitparth, F. [Department of Radiology, Charité, Humboldt-University Medical School, Charitéplatz 1, 10117 Berlin (Germany)

    2015-08-15

    Highlights: • Iterative reconstruction (IR) in staging CT provides equal objective image quality compared to filtered back projection (FBP). • IR delivers excellent subjective quality and reduces effective dose compared to FBP. • In patients with neuroendocrine tumor (NET) or may other hypervascular abdominal tumors IR can be used without scarifying diagnostic confidence. - Abstract: Objective: To investigate whether dose reduction via adaptive statistical iterative reconstruction (ASIR) affects image quality and diagnostic accuracy in neuroendocrine tumor (NET) staging. Methods: A total of 28 NET patients were enrolled in the study. Inclusion criteria were histologically proven NET and visible tumor in abdominal computed tomography (CT). In an intraindividual study design, the patients underwent a baseline CT (filtered back projection, FBP) and follow-up CT (ASIR 40%) using matched scan parameters. Image quality was assessed subjectively using a 5-grade scoring system and objectively by determining signal-to-noise ratio (SNR) and contrast-to-noise ratios (CNRs). Applied volume computed tomography dose index (CTDI{sub vol}) of each scan was taken from the dose report. Results: ASIR 40% significantly reduced CTDI{sub vol} (10.17 ± 3.06 mGy [FBP], 6.34 ± 2.25 mGy [ASIR] (p < 0.001) by 37.6% and significantly increased CNRs (complete tumor-to-liver, 2.76 ± 1.87 [FBP], 3.2 ± 2.32 [ASIR]) (p < 0.05) (complete tumor-to-muscle, 2.74 ± 2.67 [FBP], 4.31 ± 4.61 [ASIR]) (p < 0.05) compared to FBP. Subjective scoring revealed no significant changes for diagnostic confidence (5.0 ± 0 [FBP], 5.0 ± 0 [ASIR]), visibility of suspicious lesion (4.8 ± 0.5 [FBP], 4.8 ± 0.5 [ASIR]) and artifacts (5.0 ± 0 [FBP], 5.0 ± 0 [ASIR]). ASIR 40% significantly decreased scores for noise (4.3 ± 0.6 [FBP], 4.0 ± 0.8 [ASIR]) (p < 0.05), contrast (4.4 ± 0.6 [FBP], 4.1 ± 0.8 [ASIR]) (p < 0.001) and visibility of small structures (4.5 ± 0.7 [FBP], 4.3 ± 0.8 [ASIR]) (p < 0

  9. The application of PET-CT in gastrointestinal stromal tumor

    International Nuclear Information System (INIS)

    Xian Weijun; Feng Yanlin

    2009-01-01

    Gastrointestinal stromal tumor (GIST) is a mesenchymal neoplasm of uncertain malignant potential that arises predominantly in the gastrointestinal tract. Due to lack of specific physical signs, imagin g-x examination is an important auxiliary means in diagnosing gastrointestinal stromal tumor. Compared to other conventional imaging examinations, PET-CT has demonstrated unique superiority in staging, response evaluation and follow-up of gastrointestinal stromal tumor. And now it presents an overview of the application valuation of PET-CT and related imaging technology in gastrointestinal stromal tumor as follow. (authors)

  10. Comprehensive imaging of tumor recurrence in breast cancer patients using whole-body MRI at 1.5 and 3 T compared to FDG-PET-CT

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Gerwin P. [Institute of Clinical Radiology, University Hospitals Munich-Grosshadern, Marchioninistr. 15, 81377 Munich (Germany)], E-mail: gerwin.schmidt@med.uni-muenchen.de; Baur-Melnyk, Andrea [Institute of Clinical Radiology, University Hospitals Munich-Grosshadern, Marchioninistr. 15, 81377 Munich (Germany); Haug, Alexander [Department of Nuclear Medicine, University Hospitals Munich-Grosshadern, 81377 Munich (Germany); Heinemann, Volker [Department of Internal Medicine III, University Hospitals Munich-Grosshadern, 81377 Munich (Germany); Bauerfeind, Ingo [Department of Obstetrics and Gynecology, University Hospitals Munich-Grosshadern, 81377 Munich (Germany); Reiser, Maximilian F. [Institute of Clinical Radiology, University Hospitals Munich-Grosshadern, Marchioninistr. 15, 81377 Munich (Germany); Schoenberg, Stefan O. [Institute of Clinical Radiology University Hospital Mannheim, Medical Faculty Mannheim, University of Heidelberg (Germany)

    2008-01-15

    Purpose: To compare the diagnostic accuracy for the detection of tumor recurrence in breast cancer patients using whole-body-MRI (WB-MRI) at 1.5 or 3 T compared to FDG-PET-CT. Materials and methods: Thirty-three female patients with breast cancer and suspicion of recurrence underwent FDG-PET-CT and WB-MRI. Coronal T1w-TSE- and STIR-sequences, HASTE-imaging of the lungs, contrast-enhanced T1w- and T2w-TSE-sequences of the liver, brain and abdomen were performed, using a WB-MRI-scanner at 1.5 (n = 23) or 3 T (n = 10). Presence of local recurrence, lymph node involvement and distant metastatic disease was assessed using clinical and radiological follow-up as a standard of reference. Results: Tumor recurrence was found in 20 of 33 patients. Overall 186 malignant foci were detected with WB-MRI and PET-CT. Both modalities revealed two recurrent tumors of the breast. PET-CT detected more lymph node metastases (n = 21) than WB-MRI (n = 16). WB-MRI was more precise in the detection of distant metastases (n = 154 versus n = 147). Sensitivity was 93% (172/186) and 91% (170/186) for WB-MRI and PET-CT, specificity was 86% (66/77) and 90% (69/77), respectively. Examination times for WB-MRI at 1.5 and 3 T were 51 and 43 min, respectively, examination time for PET-CT was 103 min. Conclusion: WB-MRI and PET-CT are useful for the detection of tumor recurrence in the follow-up of breast cancer. WB-MRI is highly sensitive to distant metastatic disease. PET-CT is more sensitive in detecting lymph node involvement. Tumor screening with WB-MRI is feasible at 1.5 and 3 T, scan time is further reduced at 3 T with identical resolution.

  11. TH-EF-207A-06: High-Resolution Optical-CT/ECT Imaging of Unstained Mice Femur, Brain, Spleen, and Tumor

    International Nuclear Information System (INIS)

    Yoon, S; Dewhirst, M; Oldham, M; Boss, M; Birer, S

    2016-01-01

    Purpose: Optical transmission and emission computed tomography (optical-CT/ECT) provides high-resolution 3D attenuation and emission maps in unsectioned large (∼1cm 3 ) ex vivo tissue samples at a resolution of 12.9µm 3 per voxel. Here we apply optical-CT/ECT to investigate high-resolution structure and auto-fluorescence in a range of optically cleared mice organs, including, for the first time, mouse bone (femur), opening the potential for study of bone metastasis and bone-mediated immune response. Methods: Three BALBc mice containing 4T1 flank tumors were sacrificed to obtain spleen, brain, tumor, and femur. Tissues were washed in 4% PFA, fixed in EtOH solution (for 5, 10, 10, and 2 days respectively), and then optically cleared for 3 days in BABBs. The femur was also placed in 0.25M aqueous EDTA for 15–30 days to remove calcium. Optical-CT/ECT attenuation and emission maps at 633nm (the latter using 530nm excitation light) were obtained for all samples. Bi-telecentric optical-CT was compared side-by-side with conventional optical projection tomography (OPT) imaging to evaluate imaging capability of these two rival techniques. Results: Auto-fluorescence mapping of femurs reveals vasculatures and fluorescence heterogeneity. High signals (A.U.=10) are reported in the medullary cavity but not in the cortical bone (A.U.=1). The brain strongly and uniform auto-fluoresces (A.U.=5). Thick, optically dense organs such as the spleen and the tumor (0.12, 0.46OD/mm) are reconstructed at depth without significant loss of resolution, which we attribute to the bi-telecentric optics of optical-CT. The attenuation map of tumor reveals vasculature, attenuation heterogeneity, and possibly necrotic tissue. Conclusion: We demonstrate the feasibility of optical-CT/ECT imaging of un-sectioned mice bones (femurs) and spleen with high resolution. This result, and the characterization of unstained organs, are important steps enabling future studies involving optical-CT/ECT applied

  12. PEGylated (NH4)xWO3 nanorods as efficient and stable multifunctional nanoagents for simultaneous CT imaging and photothermal therapy of tumor.

    Science.gov (United States)

    Macharia, Daniel K; Tian, Qiyun; Chen, Liang; Sun, Yingqi; Yu, Nuo; He, Chuanglong; Wang, Han; Chen, Zhigang

    2017-09-01

    The simultaneous imaging and photothermal therapy of tumors have attracted much attention, and a prerequisite is to obtain multifunctional nanomaterials. Ideally, one kind of nanoparticles with single component can be used as both imaging agent and photothermal agent. Herein, we have developed the PEGylated (NH 4 ) x WO 3 (denoted as (NH 4 ) x WO 3 -PEG) nanorods as multifunctional nanoparticles with single semiconductor component. (NH 4 ) x WO 3 -PEG nanorods with about 30nm diameter and length of several hundred nanometers have been obtained through a solvothermal synthesis-PEGylation two-step route. Under the irradiation of 980-nm laser with intensity of 0.72Wcm -2 , aqueous dispersion of (NH 4 ) x WO 3 -PEG nanorods (0.67-5.44mmol/L) displays high elevation (17.6-34.5°C) of temperature in 400s, accompanied by an excellent long-term photothermal stability. Furthermore, (NH 4 ) x WO 3 -PEG nanorods exhibit as high as 6 times X-ray attenuation ability compared to that of the clinically used iodine-based X-ray computed tomography (CT) contrast agent (Iopromide). More importantly, after PBS solution of (NH 4 ) x WO 3 -PEG nanorods is injected into the tumor of mice, the tumor can be effectively detected by CT imaging. Moreover, cancer cells in vivo can be further destroyed by the photothermal effects of (NH 4 ) x WO 3 -PEG nanorods, under the irradiation of 980-nm laser with the safe intensity of 0.72Wcm -2 for 10min. Therefore, (NH 4 ) x WO 3 -PEG nanorods can be used as a new kind of stable and efficient multifunctional nanoagent with single component for simultaneous CT imaging and photothermal therapy of tumor. Copyright © 2017. Published by Elsevier B.V.

  13. Dual source CT imaging

    International Nuclear Information System (INIS)

    Seidensticker, Peter R.; Hofmann, Lars K.

    2008-01-01

    The introduction of Dual Source Computed Tomography (DSCT) in 2005 was an evolutionary leap in the field of CT imaging. Two x-ray sources operated simultaneously enable heart-rate independent temporal resolution and routine spiral dual energy imaging. The precise delivery of contrast media is a critical part of the contrast-enhanced CT procedure. This book provides an introduction to DSCT technology and to the basics of contrast media administration followed by 25 in-depth clinical scan and contrast media injection protocols. All were developed in consensus by selected physicians on the Dual Source CT Expert Panel. Each protocol is complemented by individual considerations, tricks and pitfalls, and by clinical examples from several of the world's best radiologists and cardiologists. This extensive CME-accredited manual is intended to help readers to achieve consistently high image quality, optimal patient care, and a solid starting point for the development of their own unique protocols. (orig.)

  14. CT images of gossypiboma

    International Nuclear Information System (INIS)

    Jeon, Hae Jeong; Lim, Jong Nam; Choi, Young Chil; Park, Jeong Hee

    1994-01-01

    Surgical sponges retained after laparotomy can cause serious problem if they were not be identified in early state. In these circumstances abdominal CT yields the accurate diagnostic images. The purpose of this report is to present highly indicative findings permitting correct preoperative diagnosis of the gossypiboma. We experienced three cases in which CT showed the images sufficiently characteristic to suggest the correct preoperative diagnosis. We evaluated retrospectively the radiological images of gossypiboma confirmed by operation. Three patients were admitted due to palpable masses. Two female patients had medical histories of cesarean sections and a male patient had been operated due to malignant fibrous histiocytoma, previously. Abdominal CT scan of one case revealed huge ovoid hypodense mass with enhanced peripheral rim. Calcific spots and whirl-like stripes were noted within the lesion. Towel was found in pathologic specimen. CT images of two patients showed well-encapsulated, mixed fluid and soft tissue density mass with several gas bubbles. Surgical sponges were found within abscesses. The authors conclude that these characteristic CT findings and careful histories of surgery are very useful for correct pre-operative diagnosis and permit the guideline for the optimal plan of the surgical treatment

  15. CT images of gossypiboma

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Hae Jeong; Lim, Jong Nam; Choi, Young Chil; Park, Jeong Hee [College of Medicine, Kon-Kuk University, Seoul (Korea, Republic of)

    1994-04-15

    Surgical sponges retained after laparotomy can cause serious problem if they were not be identified in early state. In these circumstances abdominal CT yields the accurate diagnostic images. The purpose of this report is to present highly indicative findings permitting correct preoperative diagnosis of the gossypiboma. We experienced three cases in which CT showed the images sufficiently characteristic to suggest the correct preoperative diagnosis. We evaluated retrospectively the radiological images of gossypiboma confirmed by operation. Three patients were admitted due to palpable masses. Two female patients had medical histories of cesarean sections and a male patient had been operated due to malignant fibrous histiocytoma, previously. Abdominal CT scan of one case revealed huge ovoid hypodense mass with enhanced peripheral rim. Calcific spots and whirl-like stripes were noted within the lesion. Towel was found in pathologic specimen. CT images of two patients showed well-encapsulated, mixed fluid and soft tissue density mass with several gas bubbles. Surgical sponges were found within abscesses. The authors conclude that these characteristic CT findings and careful histories of surgery are very useful for correct pre-operative diagnosis and permit the guideline for the optimal plan of the surgical treatment.

  16. Impact of tumor attachment to the pleura measured by a pretreatment CT image on outcome of stage I NSCLC treated with stereotactic body radiotherapy

    International Nuclear Information System (INIS)

    Yamamoto, Takaya; Kadoya, Noriyuki; Shirata, Yuko; Koto, Masashi; Sato, Kiyokazu; Matsushita, Haruo; Sugawara, Toshiyuki; Umezawa, Rei; Kubozono, Masaki; Ishikawa, Yojiro; Kozumi, Maiko; Takahashi, Noriyoshi; Ito, Kengo; Katagiri, Yu; Takeda, Ken; Jingu, Keiichi

    2015-01-01

    Pleural invasion status is known to be a predictor of survival after pulmonary resection for non-small cell lung cancer. Our goal was to determine whether the length of tumor attachment to the pleura on a pretreatment CT image has prognostic value as an alternative to pleural invasion status for stage I non-small cell lung cancer treated with stereotactic body radiotherapy (SBRT). A total of 90 tumors in 87 patients (males: 68, females: 19) who received SBRT between March 2005 and September 2011 in our institution were reviewed. The median age of the patients was 78 years (range, 48-90 years). The median tumor diameter was 2.2 cm (range, 0.9-4.2 cm). The prescribed dose was typically 48 Gy in 4 fractions, 60 Gy in 8 fractions or 60 Gy in 15 fractions to the isocenter with 6 MV X-ray using 4 non-coplanar and 3 coplanar static beams. The lengths of attachment were measured using pretreatment CT images at the lung window. Cumulative incidence rates were calculated using Kaplan-Meier curves, and univariate and multivariate analyses for in-field tumor control, locoregional control (LRC), freedom from distant metastasis and freedom from progression (FFP) were performed using a Cox proportional hazards model. Of the 90 tumors, 42 tumors were attached to the pleura (median, 14.7 mm; range, 4.3-36.0 mm), 21 tumors had pleural indentation and 27 tumors had no attachment. The median follow-up period for survivors was 46.1 months. The 3-year in-field control, LRC, FFP and overall survival rates were 91.2%, 75.3%, 63.8% and 68.6%, respectively. SBRT dose and tumor diameter were independently significant predictors of in-field control (p = 0.02 and p = 0.04, respectively). Broad attachment to the pleura, the length being more than 14.7 mm, was a negative independent predictor of LRC and FFP (p = 0.02 and p = 0.01, respectively). Pleural attachment status on a pretreatment CT image might be an important predictor of LRC and FFP

  17. Warthin's Tumor of the Parotid Gland: CT and MR Features

    International Nuclear Information System (INIS)

    Lee, Yun Hee; Yu, In Kyu; Lee, Byung Hee; Kim, Min Sun; Han, Moon Hee; Song, Chang Joon

    2009-01-01

    In this study, we have evaluated the imaging features of Warthin's tumor of the parotid gland with the use of CT and MR imaging. CT (n = 30) and MR (n = 7) images of 26 patients (M:F=23:3; age range, 38-76 years; mean age, 58 years) with surgically-proven Warthin's tumor (n = 37) were reviewed with a focus on bilaterality, multiplicity, location, size, demarcation, margin, enhancement pattern and MR signal intensity. Lesions were bilateral in seven patients (27%), multiple in nine patients (35%) and unilateral multiple in four patients (15%). Tumors were located in the superficial lobe (65%), deep lobe (24%) and both lobes (11%) of the parotid gland. Most tumors had a clear (95%) and smooth margin (95%) with a round or oval shape. Tumors mainly showed a solid and cystic composition (n = 24, 65%) and all solid stroma showed poor or weak enhancement on both CT and MR images. Papillary projections from the peripheral wall were clearly seen (n = 6, 86%). Warthin's tumor is frequently seen in the parotid superficial lobe of older males with a higher bilateral and multiple tendency. Warthin's tumor shows cystic portions with papillary projections at the wall on CT images and focal high signal intensity (SI) on T1-weighted images with dense nodular enhancement on MR images

  18. CT image of thymoma

    Energy Technology Data Exchange (ETDEWEB)

    Morioka, Nobuo; Shudo, Yuji; Jahana, Masanobu; Matsuki, Tsutomu; Kotani, Kazuhiko (Tottori Univ., Yonago (Japan). School of Medicine)

    1983-10-01

    Computor tomographic images of 11 patients who had had thymectomy for myasthenia gravis or thymoma were studied retrospectively. Of those 11 patients, malignant thymoma and benign condition including normal thymus were 6 and 5 respectively. On CT, calcification and lobulation with irregular margin seem to be reliable findings of malignancy. Defect or abscence of fatty plane and non-homogenous density are ancillary.

  19. CT image of thymoma

    International Nuclear Information System (INIS)

    Morioka, Nobuo; Shudo, Yuji; Jahana, Masanobu; Matsuki, Tsutomu; Kotani, Kazuhiko

    1983-01-01

    Computor tomographic images of 11 patients who had had thymectomy for myasthenia gravis or thymoma were studied retrospectively. Of those 11 patients, malignant thymoma and benign condition including normal thymus were 6 and 5 respectively. On CT, calcification and lobulation with irregular margin seem to be reliable findings of malignancy. Defect or abscence of fatty plane and non-homogenous density are ancillary. (author)

  20. Pulmonary hypertension CT imaging

    International Nuclear Information System (INIS)

    Nedevska, A.

    2013-01-01

    Full text: The right heart catheterization is the gold standard in the diagnosis and determines the severity of pulmonary hypertension. The significant technical progress of noninvasive diagnostic imaging methods significantly improves the pixel density and spatial resolution in the study of cardiovascular structures, thus changes their role and place in the overall diagnostic plan. Learning points: What is the etiology, clinical manifestation and general pathophysiological disorders in pulmonary hypertension. What are the established diagnostic methods in the diagnosis and follow-up of patients with pulmonary hypertension. What is the recommended protocol for CT scanning for patients with clinically suspected or documented pulmonary hypertension. What are the important diagnostic findings in CT scan of a patient with pulmonary hypertension. Discussion: The prospect of instantaneous complex - anatomical and functional cardiopulmonary and vascular diagnostics seems extremely attractive. The contrast enhanced multislice computed (CT ) and magnetic resonance imaging are very suitable methods for imaging the structures of the right heart, with the possibility of obtaining multiple projections and three-dimensional imaging reconstructions . There are specific morphological features that, if carefully analyzed, provide diagnostic information. Thus, it is possible to avoid or at least reduce the frequency of use of invasive diagnostic cardiac catheterization in patients with pulmonary hypertension. Conclusion: This review focuses on the use of contrast-enhanced CT for comprehensive evaluation of patients with pulmonary hypertension and presents the observed characteristic changes in the chest, lung parenchyma , the structures of the right half of the heart and pulmonary vessels

  1. TU-H-CAMPUS-JeP2-03: Machine-Learning-Based Delineation Framework of GTV Regions of Solid and Ground Glass Opacity Lung Tumors at Datasets of Planning CT and PET/CT Images

    Energy Technology Data Exchange (ETDEWEB)

    Ikushima, K; Arimura, H; Jin, Z; Yabuuchi, H; Sasaki, T; Honda, H; Sasaki, M [Kyushu University, Fukuoka, Fukuoka (Japan); Kuwazuru, J [Saiseikai Fukuoka General Hospital, Fukuoka, Fukuoka (Japan); Shioyama, Y [Saga Heavy Ion Medical Accelerator in Tosu, Tosu, Saga (Japan)

    2016-06-15

    Purpose: In radiation treatment planning, delineation of gross tumor volume (GTV) is very important, because the GTVs affect the accuracies of radiation therapy procedure. To assist radiation oncologists in the delineation of GTV regions while treatment planning for lung cancer, we have proposed a machine-learning-based delineation framework of GTV regions of solid and ground glass opacity (GGO) lung tumors following by optimum contour selection (OCS) method. Methods: Our basic idea was to feed voxel-based image features around GTV contours determined by radiation oncologists into a machine learning classifier in the training step, after which the classifier produced the degree of GTV for each voxel in the testing step. Ten data sets of planning CT and PET/CT images were selected for this study. The support vector machine (SVM), which learned voxel-based features which include voxel value and magnitudes of image gradient vector that obtained from each voxel in the planning CT and PET/CT images, extracted initial GTV regions. The final GTV regions were determined using the OCS method that was able to select a global optimum object contour based on multiple active delineations with a level set method around the GTV. To evaluate the results of proposed framework for ten cases (solid:6, GGO:4), we used the three-dimensional Dice similarity coefficient (DSC), which denoted the degree of region similarity between the GTVs delineated by radiation oncologists and the proposed framework. Results: The proposed method achieved an average three-dimensional DSC of 0.81 for ten lung cancer patients, while a standardized uptake value-based method segmented GTV regions with the DSC of 0.43. The average DSCs for solid and GGO were 0.84 and 0.76, respectively, obtained by the proposed framework. Conclusion: The proposed framework with the support vector machine may be useful for assisting radiation oncologists in delineating solid and GGO lung tumors.

  2. Imaging tumors of the patella

    Energy Technology Data Exchange (ETDEWEB)

    Casadei, R., E-mail: roberto.casadei@ior.it [Department of Orthopaedic Oncology, Istituto Ortopedico Rizzoli, Bologna (Italy); Kreshak, J., E-mail: j.kreshak@yahoo.com [Department of Orthopaedic Oncology, Istituto Ortopedico Rizzoli, Bologna (Italy); Department of Pathology, Istituto Ortopedico Rizzoli, Bologna (Italy); Rinaldi, R. [Department of Radiology, Istituto Ortopedico Rizzoli, Bologna (Italy); Rimondi, E., E-mail: eugenio.rimondi@ior.it [Department of Radiology, Istituto Ortopedico Rizzoli, Bologna (Italy); Bianchi, G., E-mail: giuseppe.bianchi@ior.it [Department of Orthopaedic Oncology, Istituto Ortopedico Rizzoli, Bologna (Italy); Alberghini, M., E-mail: marco.alberghini@ior.it [Department of Pathology, Istituto Ortopedico Rizzoli, Bologna (Italy); Ruggieri, P. [Department of Orthopaedic Oncology, Istituto Ortopedico Rizzoli, Bologna (Italy); Vanel, D., E-mail: daniel.vanel@ior.it [Department of Radiology, Istituto Ortopedico Rizzoli, Bologna (Italy); Department of Pathology, Istituto Ortopedico Rizzoli, Bologna (Italy)

    2013-12-01

    Background: Patellar tumors are rare; only a few series have been described in the literature and radiographic diagnosis can be challenging. We reviewed all patellar tumors at one institution and reviewed the literature. Materials and methods: In an evaluation of the database at one institution from 1916 to 2009, 23,000 bone tumors were found. Of these, 41 involved the patella. All had imaging studies and microscopic diagnostic confirmation. All medical records, imaging studies, and pathology were reviewed. Results: There were 15 females and 26 males, ranging from 8 to 68 years old (average 30). There were 30 benign tumors; eight giant cell tumors, eight chondroblastomas, seven osteoid osteomas, two aneurysmal bone cysts, two ganglions, one each of chondroma, exostosis, and hemangioma. There were 11 malignant tumors: five hemangioendotheliomas, three metastases, one lymphoma, one plasmacytoma, and one angiosarcoma. Conclusion: Patellar tumors are rare and usually benign. As the patella is an apophysis, the most frequent lesions are giant cell tumor in the adult and chondroblastoma in children. Osteoid osteomas were frequent in our series and easily diagnosed. Metastases are the most frequent malignant diagnoses in the literature; in our series malignant vascular tumors were more common. These lesions are often easily analyzed on radiographs. CT and MR define better the cortex, soft tissue extension, and fluid levels. This study presents the imaging patterns of the more common patellar tumors in order to help the radiologist when confronted with a lesion in this location.

  3. An evaluation of the variability of tumor-shape definition derived by experienced observers from CT images of supraglottic carcinomas (ACRIN protocol 6658)

    International Nuclear Information System (INIS)

    Cooper, Jay S.; Mukherji, Suresh K.; Toledano, Alicia Y.; Beldon, Clifford; Schmalfuss, Ilona M.; Amdur, Robert; Sailer, Scott; Loevner, Laurie A.; Kousouboris, Phil; Ang, K. Kian; Cormack, Jean; Sicks, JoRean M.S.

    2007-01-01

    Purpose: Accurate target definition is considered essential for sophisticated, image-guided radiation therapy; however, relatively little information has been reported that measures our ability to identify the precise shape of targets accurately. We decided to assess the manner in which eight 'experts' interpreted the size and shape of tumors based on 'real-life' contrast-enhanced computed tomographic (CT) scans. Methods and Materials: Four neuroradiologists and four radiation oncologists (the authors) with considerable experience and presumed expertise in treating head-and-neck tumors independently contoured, slice-by-slice, his/her interpretation of the precise gross tumor volume (GTV) on each of 20 sets of CT scans taken from 20 patients who previously were enrolled in Radiation Therapy Oncology Group protocol 91-11. Results: The average proportion of overlap (i.e., the degree of agreement) was 0.532 (95% confidence interval 0.457 to 0.606). There was a slight tendency for the proportion of overlap to increase with increasing average GTV. Conclusions: Our work suggests that estimation of tumor shape currently is imprecise, even for experienced physicians. In consequence, there appears to be a practical limit to the current trend of smaller fields and tighter margins

  4. Comparison of applied dose and image quality in staging CT of neuroendocrine tumor patients using standard filtered back projection and adaptive statistical iterative reconstruction.

    Science.gov (United States)

    Böning, G; Schäfer, M; Grupp, U; Kaul, D; Kahn, J; Pavel, M; Maurer, M; Denecke, T; Hamm, B; Streitparth, F

    2015-08-01

    To investigate whether dose reduction via adaptive statistical iterative reconstruction (ASIR) affects image quality and diagnostic accuracy in neuroendocrine tumor (NET) staging. A total of 28 NET patients were enrolled in the study. Inclusion criteria were histologically proven NET and visible tumor in abdominal computed tomography (CT). In an intraindividual study design, the patients underwent a baseline CT (filtered back projection, FBP) and follow-up CT (ASIR 40%) using matched scan parameters. Image quality was assessed subjectively using a 5-grade scoring system and objectively by determining signal-to-noise ratio (SNR) and contrast-to-noise ratios (CNRs). Applied volume computed tomography dose index (CTDIvol) of each scan was taken from the dose report. ASIR 40% significantly reduced CTDIvol (10.17±3.06mGy [FBP], 6.34±2.25mGy [ASIR] (pASIR]) (pASIR]) (pASIR]), visibility of suspicious lesion (4.8±0.5 [FBP], 4.8±0.5 [ASIR]) and artifacts (5.0±0 [FBP], 5.0±0 [ASIR]). ASIR 40% significantly decreased scores for noise (4.3±0.6 [FBP], 4.0±0.8 [ASIR]) (pASIR]) (pASIR]) (pASIR can be used to reduce radiation dose without sacrificing image quality and diagnostic confidence in staging CT of NET patients. This may be beneficial for patients with frequent follow-up and significant cumulative radiation exposure. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. Experimental validation of heterogeneity-corrected dose-volume prescription on respiratory-averaged CT images in stereotactic body radiotherapy for moving tumors

    International Nuclear Information System (INIS)

    Nakamura, Mitsuhiro; Miyabe, Yuki; Matsuo, Yukinori; Kamomae, Takeshi; Nakata, Manabu; Yano, Shinsuke; Sawada, Akira; Mizowaki, Takashi; Hiraoka, Masahiro

    2012-01-01

    The purpose of this study was to experimentally assess the validity of heterogeneity-corrected dose-volume prescription on respiratory-averaged computed tomography (RACT) images in stereotactic body radiotherapy (SBRT) for moving tumors. Four-dimensional computed tomography (CT) data were acquired while a dynamic anthropomorphic thorax phantom with a solitary target moved. Motion pattern was based on cos (t) with a constant respiration period of 4.0 sec along the longitudinal axis of the CT couch. The extent of motion (A 1 ) was set in the range of 0.0–12.0 mm at 3.0-mm intervals. Treatment planning with the heterogeneity-corrected dose-volume prescription was designed on RACT images. A new commercially available Monte Carlo algorithm of well-commissioned 6-MV photon beam was used for dose calculation. Dosimetric effects of intrafractional tumor motion were then investigated experimentally under the same conditions as 4D CT simulation using the dynamic anthropomorphic thorax phantom, films, and an ionization chamber. The passing rate of γ index was 98.18%, with the criteria of 3 mm/3%. The dose error between the planned and the measured isocenter dose in moving condition was within ± 0.7%. From the dose area histograms on the film, the mean ± standard deviation of the dose covering 100% of the cross section of the target was 102.32 ± 1.20% (range, 100.59–103.49%). By contrast, the irradiated areas receiving more than 95% dose for A 1 = 12 mm were 1.46 and 1.33 times larger than those for A 1 = 0 mm in the coronal and sagittal planes, respectively. This phantom study demonstrated that the cross section of the target received 100% dose under moving conditions in both the coronal and sagittal planes, suggesting that the heterogeneity-corrected dose-volume prescription on RACT images is acceptable in SBRT for moving tumors.

  6. Comparison of Tumor Volumes as Determined by Pathologic Examination and FDG-PET/CT Images of Non-Small-Cell Lung Cancer: A Pilot Study

    International Nuclear Information System (INIS)

    Yu Jinming; Li Xinke; Xing Ligang; Mu Dianbin; Fu Zheng; Sun Xiaorong; Sun Xiangyu; Yang Guoren; Zhang Baijiang; Sun Xindong; Ling, C. Clifton

    2009-01-01

    Purpose: To determine the cut-off standardized uptake value (SUV) on 18 F fluoro-2-deoxy-glucose (FDG) positron emission tomography/computed tomography (FDG-PET/CT) images that generates the best volumetric match to pathologic gross tumor volume (GTV path ) for non-small-cell lung cancer (NSCLC). Methods and Materials: Fifteen patients with NSCLC who underwent FDG-PET/CT scans followed by lobectomy were enrolled. The surgical specimen was dissected into 5-7-μm sections at approximately 4-mm intervals and stained with hematoxylin and eosin. The tumor-containing area was outlined slice by slice and the GTV path determined by summing over all the slices, taking into account the interslice thickness and fixation-induced volume reduction. The gross tumor volume from the PET images, GTV PET , was determined as a function of cut-off SUV. The optimal threshold or optimal absolute SUV was defined as the value at which the GTV PET was the same as the GTV path . Results: The fixation process induced a volumetric reduction to 82% ± 10% (range, 62-100%) of the original. The maximal SUV was 10.1 ± 3.6 (range, 4.2-18.7). The optimal threshold and absolute SUV were 31% ± 11% and 3.0 ± 1.6, respectively. The optimal threshold was inversely correlated with GTV path and tumor diameter (p path or tumor diameter (p > 0.05). Conclusion: This study evaluated the use of GTV path as a criterion for determining the optimal cut-off SUV for NSCLC target volume delineation. Confirmatory studies including more cases are being performed.

  7. Therapeutic response assessment using 3D ultrasound for hepatic metastasis from colorectal cancer: Application of a personalized, 3D-printed tumor model using CT images.

    Directory of Open Access Journals (Sweden)

    Ye Ra Choi

    Full Text Available To evaluate accuracy and reliability of three-dimensional ultrasound (3D US for response evaluation of hepatic metastasis from colorectal cancer (CRC using a personalized 3D-printed tumor model.Twenty patients with liver metastasis from CRC who underwent baseline and after chemotherapy CT, were retrospectively included. Personalized 3D-printed tumor models using CT were fabricated. Two radiologists measured volume of each 3D printing model using 3D US. With CT as a reference, we compared difference between CT and US tumor volume. The response evaluation was based on Response Evaluation Criteria in Solid Tumors (RECIST criteria.3D US tumor volume showed no significant difference from CT volume (7.18 ± 5.44 mL, 8.31 ± 6.32 mL vs 7.42 ± 5.76 mL in CT, p>0.05. 3D US provided a high correlation coefficient with CT (r = 0.953, r = 0.97 as well as a high inter-observer intraclass correlation (0.978; 0.958-0.988. Regarding response, 3D US was in agreement with CT in 17 and 18 out of 20 patients for observer 1 and 2 with excellent agreement (κ = 0.961.3D US tumor volume using a personalized 3D-printed model is an accurate and reliable method for the response evaluation in comparison with CT tumor volume.

  8. Evaluation of a New Motion-correction Algorithm Using On-rigid Registration in Respiratory-gated PET/CT Images of Liver Tumors.

    Science.gov (United States)

    Wagatsuma, Kei; Osawa, Tatsufumi; Yokokawa, Naoki; Miwa, Kenta; Oda, Keiichi; Kudo, Yoshiro; Unno, Yasushi; Ito, Kimiteru; Ishii, Kenji

    2016-01-01

    The present study aimed to determine the qualitative and quantitative accuracy of the Q.Freeze algorithm in PET/CT images of liver tumors. A body phantom and hot spheres representing liver tumors contained 5.3 and 21.2 kBq/mL of a solution containing 18 F radioactivity, respectively. The phantoms were moved in the superior-inferior direction at a motion displacement of 20 mm. Conventional respiratory-gated (RG) and Q.Freeze images were sorted into 6, 10, and 13 phase-groups. The SUV ave was calculated from the background of the body phantom, and the SUV max was determined from the hot spheres of the liver tumors. Three patients with four liver tumors were also clinically assessed by whole-body and RG PET. The RG and Q.Freeze images derived from the clinical study were also sorted into 6, 10 and 13 phase-groups. Liver signal-to-noise ratio (SNR) and SUV max were determined from the RG and Q.Freeze clinical images. The SUV ave of Q.Freeze images was the same as those derived from the body phantom using RG. The liver SNR improved with Q.Freeze, and the SUVs max was not overestimated when Q.Freeze was applied in both the phantom and clinical studies. Q.Freeze did not degrade the liver SNR and SUV max even though the phase number was larger. Q.Freeze delivered qualitative and quantitative motion correction than conventional RG imaging even in 10-phase groups.

  9. First application of liquid-metal-jet sources for small-animal imaging: High-resolution CT and phase-contrast tumor demarcation

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, Daniel H.; Lundstroem, Ulf; Burvall, Anna; Hertz, Hans M. [Department of Applied Physics, KTH Royal Institute of Technology/Albanova, 10691 Stockholm (Sweden); Westermark, Ulrica K.; Arsenian Henriksson, Marie [Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, 17177 Stockholm (Sweden)

    2013-02-15

    Purpose: Small-animal studies require images with high spatial resolution and high contrast due to the small scale of the structures. X-ray imaging systems for small animals are often limited by the microfocus source. Here, the authors investigate the applicability of liquid-metal-jet x-ray sources for such high-resolution small-animal imaging, both in tomography based on absorption and in soft-tissue tumor imaging based on in-line phase contrast. Methods: The experimental arrangement consists of a liquid-metal-jet x-ray source, the small-animal object on a rotating stage, and an imaging detector. The source-to-object and object-to-detector distances are adjusted for the preferred contrast mechanism. Two different liquid-metal-jet sources are used, one circulating a Ga/In/Sn alloy and the other an In/Ga alloy for higher penetration through thick tissue. Both sources are operated at 40-50 W electron-beam power with {approx}7 {mu}m x-ray spots, providing high spatial resolution in absorption imaging and high spatial coherence for the phase-contrast imaging. Results: High-resolution absorption imaging is demonstrated on mice with CT, showing 50 {mu}m bone details in the reconstructed slices. High-resolution phase-contrast soft-tissue imaging shows clear demarcation of mm-sized tumors at much lower dose than is required in absorption. Conclusions: This is the first application of liquid-metal-jet x-ray sources for whole-body small-animal x-ray imaging. In absorption, the method allows high-resolution tomographic skeletal imaging with potential for significantly shorter exposure times due to the power scalability of liquid-metal-jet sources. In phase contrast, the authors use a simple in-line arrangement to show distinct tumor demarcation of few-mm-sized tumors. This is, to their knowledge, the first small-animal tumor visualization with a laboratory phase-contrast system.

  10. Accuracy and inter-observer variability of 3D versus 4D cone-beam CT based image-guidance in SBRT for lung tumors

    Directory of Open Access Journals (Sweden)

    Sweeney Reinhart A

    2012-06-01

    Full Text Available Abstract Background To analyze the accuracy and inter-observer variability of image-guidance (IG using 3D or 4D cone-beam CT (CBCT technology in stereotactic body radiotherapy (SBRT for lung tumors. Materials and methods Twenty-one consecutive patients treated with image-guided SBRT for primary and secondary lung tumors were basis for this study. A respiration correlated 4D-CT and planning contours served as reference for all IG techniques. Three IG techniques were performed independently by three radiation oncologists (ROs and three radiotherapy technicians (RTTs. Image-guidance using respiration correlated 4D-CBCT (IG-4D with automatic registration of the planning 4D-CT and the verification 4D-CBCT was considered gold-standard. Results were compared with two IG techniques using 3D-CBCT: 1 manual registration of the planning internal target volume (ITV contour and the motion blurred tumor in the 3D-CBCT (IG-ITV; 2 automatic registration of the planning reference CT image and the verification 3D-CBCT (IG-3D. Image quality of 3D-CBCT and 4D-CBCT images was scored on a scale of 1–3, with 1 being best and 3 being worst quality for visual verification of the IGRT results. Results Image quality was scored significantly worse for 3D-CBCT compared to 4D-CBCT: the worst score of 3 was given in 19 % and 7.1 % observations, respectively. Significant differences in target localization were observed between 4D-CBCT and 3D-CBCT based IG: compared to the reference of IG-4D, tumor positions differed by 1.9 mm ± 0.9 mm (3D vector on average using IG-ITV and by 3.6 mm ± 3.2 mm using IG-3D; results of IG-ITV were significantly closer to the reference IG-4D compared to IG-3D. Differences between the 4D-CBCT and 3D-CBCT techniques increased significantly with larger motion amplitude of the tumor; analogously, differences increased with worse 3D-CBCT image quality scores. Inter-observer variability was largest in SI direction and was

  11. Bubble-generating nano-lipid carriers for ultrasound/CT imaging-guided efficient tumor therapy.

    Science.gov (United States)

    Zhang, Nan; Li, Jia; Hou, Ruirui; Zhang, Jiangnan; Wang, Pei; Liu, Xinyang; Zhang, Zhenzhong

    2017-12-20

    Ideal therapeutic effectiveness of chemotherapy is obtained only when tumor cells are exposed to a maximal drug concentration, which is often hindered by dose-limiting toxicity. We designed a bubble-generating liposomal delivery system by introducing ammonium bicarbonate and gold nanorods into folic acid-conjugated liposomes to allow both multimodal imaging and the local release of drug (doxorubicin) with hyperthermia. The key component, ammonium bicarbonate, allows a controlled, rapid release of doxorubicin to provide an effective drug concentration in the tumor microenvironment. An in vitro temperature-triggered drug release study showed that cumulative release improved more than two-fold. In addition, in vitro and in vivo studies indicated that local heat treatment or ultrasonic cavitation enhanced the therapeutic efficiency greatly. The delivery system could also serve as an excellent contrast agent to allow ultrasonic imaging and computerized tomography imaging simultaneously to further achieve the aim of accurate diagnostics. Results of this study showed that this versatile bubble-generating liposome is a promising system to provide optimal therapeutic effects that are guided by multimodal imaging. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. CT morphology of benign median nerve tumors

    International Nuclear Information System (INIS)

    Feyerabend, T.; Schmitt, R.; Lanz, U.; Warmuth-Metz, M.; Wuerzburg Univ.

    1990-01-01

    Computed tomography (CT) was performed in 3 patients with benign tumors of the median nerve, histologically confirmed as neurilemmoma, fibrolipoma and hemangioma. The neurilemmoma showed a ring-shaped contrast enhancement. The fibrolipoma presented with areas of solid soft tissue and areas of fat. The hemangioma was a solid tumor with a lacunar, vascular contrast enhancement. According to our experience and to the previous literature CT gives useful information regarding the anatomic location, size, and relationship of peripheral nerve sheath tumors to surrounding structures, and may help to differentiate between various tumor types. (orig.)

  13. Comparison of abdominal MRI with diffusion-weighted imaging to {sup 68}Ga-DOTATATE PET/CT in detection of neuroendocrine tumors of the pancreas

    Energy Technology Data Exchange (ETDEWEB)

    Schmid-Tannwald, Christine; Schmid-Tannwald, Christoph M.; Neumann, Ralph; Nikolaou, Konstantin; Schramm, Nicolai; Reiser, Maximilian F.; Rist, Carsten [Ludwig Maximilians University Hospital Munich, Institute for Clinical Radiology, Munich (Germany); Morelli, John N. [Scott and White Hospital Temple, Department of Radiology, Temple, TX (United States); Haug, Alexander R.; Jansen, Nathalie [Ludwig Maximilians University Hospital Munich, Department of Nuclear Medicine, Munich (Germany)

    2013-06-15

    The aim of the study was to evaluate contrast-enhanced MRI, diffusion-weighted MRI (DW MRI), and {sup 68}Ga-DOTATATE positron emission tomography (PET)/CT in the detection of intermediate to well-differentiated neuroendocrine tumors (NET) of the pancreas. Eighteen patients with pathologically proven pancreatic NET who underwent MRI including DW MRI and PET/CT within 6 weeks of each other were included in this retrospective study. Two radiologists evaluated T2-weighted (T2w), T2w + DW MRI, T2w + contrast-enhanced T1-weighted (CE T1w) MR images, and PET/CT for NET detection. The sensitivity and level of diagnostic confidence were compared among modalities using McNemar's test and a Wilcoxon signed rank test. Apparent diffusion coefficients (ADC) of pancreatic NETs and normal pancreatic tissue were compared with Student's t test. Of the NETs, 8/23 (34.8 %) and 9/23 (39.1 %) were detected on T2w images by observers 1 and 2, respectively. Detection rates improved significantly by combining T2w images with DW MRI (observer 1: 14/23 = 61 %; observer 2: 15/23 = 65.2 %; p < 0.05) or CE T1w images (observer 1: 14/23 = 61 %; observer 2: 15/23 = 65.2 %; p < 0.05). Detection rates of pancreatic NET with PET/CT (both observers: 23/23 = 100 %) were statistically significantly higher than with MRI (p < 0.05). The mean ADC value of NET (1.02 {+-} 0.26 x 10{sup -3} mm{sup 2}/s) was statistically significantly lower than that of normal pancreatic tissue (1.48 {+-} 0.39 x 10{sup -3} mm{sup 2}/s). DW MRI is a valuable adjunct to T2w imaging and comparable to CE T1w imaging in pancreatic NET detection, quantitatively differentiating between NET and normal pancreatic tissue with ADC measurements. {sup 68}Ga-DOTATATE PET/CT is more sensitive than MRI in the detection of pancreatic NET. (orig.)

  14. Quantitative dual energy CT measurements in rabbit VX2 liver tumors: Comparison to perfusion CT measurements and histopathological findings

    International Nuclear Information System (INIS)

    Zhang, Long Jiang; Wu, Shengyong; Wang, Mei; Lu, Li; Chen, Bo; Jin, Lixin; Wang, Jiandong; Larson, Andrew C.; Lu, Guang Ming

    2012-01-01

    Purpose: To evaluate the correlation between quantitative dual energy CT and perfusion CT measurements in rabbit VX2 liver tumors. Materials and methods: This study was approved by the institutional animal care and use committee at our institution. Nine rabbits with VX2 liver tumors underwent contrast-enhanced dual energy CT and perfusion CT. CT attenuation for the tumors and normal liver parenchyma and tumor-to-liver ratio were obtained at the 140 kVp, 80 kVp, average weighted images and dual energy CT iodine maps. Quantitative parameters for the viable tumor and adjacent liver were measured with perfusion CT. The correlation between the enhancement values of the tumor in iodine maps and perfusion CT parameters of each tumor was analyzed. Radiation dose from dual energy CT and perfusion CT was measured. Results: Enhancement values for the tumor were higher than that for normal liver parenchyma at the hepatic arterial phase (P < 0.05). The highest tumor-to-liver ratio was obtained in hepatic arterial phase iodine map. Hepatic blood flow of the tumor was higher than that for adjacent liver (P < 0.05). Enhancement values of hepatic tumors in the iodine maps positively correlated with permeability of capillary vessel surface (r = 0.913, P < 0.001), hepatic blood flow (r = 0.512, P = 0.010), and hepatic blood volume (r = 0.464, P = 0.022) at the hepatic arterial phases. The effective radiation dose from perfusion CT was higher than that from DECT (P < 0.001). Conclusions: The enhancement values for viable tumor tissues measured in iodine maps were well correlated to perfusion CT measurements in rabbit VX2 liver tumors. Compared with perfusion CT, dual energy CT of the liver required a lower radiation dose.

  15. A comparison of 111In- or 64Cu-DOTA-trastuzumab Fab fragments for imaging subcutaneous HER2-positive tumor xenografts in athymic mice using microSPECT/CT or microPET/CT

    Science.gov (United States)

    2011-01-01

    Background Our objective was to compare 111In- or 64Cu-DOTA-trastuzumab Fab fragments for imaging small or large s.c. tumor xenografts in athymic mice that display a wide range of human epidermal growth factor receptor-2 (HER2) expression using microSPECT/CT or microPET/CT. Methods Trastuzumab Fab were labeled with 111In or 64Cu by conjugation to 1,4,7,10-tetraazacyclododecane N, N', N'', N'''-tetraacetic acid (DOTA). The purity of 111In- and 64Cu-DOTA-trastuzumab Fab was measured by SDS-PAGE and HPLC. HER2 binding affinity was determined in saturation radioligand binding assays using SKBR-3 cells (1.3 × 106 HER2/cell). MicroSPECT/CT and microPET/CT were performed in athymic mice bearing s.c. BT-20 and MDA-MB-231 xenografts with low (0.5 to 1.6 × 105 receptors/cell), MDA-MB-361 tumors with intermediate (5.1 × 105 receptors/cell) or SKOV-3 xenografts with high HER2 expression (1.2 × 106 receptors/cell) at 24 h p.i. of 70 MBq (10 μg) of 111In-DOTA-trastuzumab Fab or 22 MBq (10 μg) of 64Cu-DOTA-trastuzumab Fab or irrelevant 111In- or 64Cu-DOTA-rituximab Fab. Tumor and normal tissue uptake were quantified in biodistribution studies. Results 111In- and 64Cu-DOTA-trastuzumab were > 98% radiochemically pure and bound HER2 with high affinity (Kd = 20.4 ± 2.5 nM and 40.8 ± 3.5 nM, respectively). MDA-MB-361 and SKOV-3 tumors were most clearly imaged using 111In- and 64Cu-DOTA-trastuzumab Fab. Significantly higher tumor/blood (T/B) ratios were found for 111In-DOTA-trastuzumab Fab than 111In-DOTA-rituximab Fab for BT-20, MDA-MB-231 and MDA-MB-361 xenografts, and there was a direct association between T/B ratios and HER2 expression. In contrast, tumor uptake of 64Cu-DOTA-trastuzumab Fab was significantly higher than 64Cu-DOTA-rituximab Fab in MDA-MB-361 tumors but no direct association with HER2 expression was found. Both 111In- and 64Cu-DOTA-trastuzumab Fab imaged small (5 to 10 mm) or larger (10 to 15 mm) MDA-MB-361 tumors. Higher blood, liver, and spleen

  16. CT findings of parotid gland tumors: benign versus malignant tumors

    International Nuclear Information System (INIS)

    Lee, Moon Ok; Han, Chun Hwan; Kim, Mie Young; Yi, Jeong Geun; Park, Kyung Joo; Lee, Joo Hyuk; Bae, Sang Hoon; Kim, Jeung Sook

    1994-01-01

    The purpose of this study is to evaluate the characteristics of parotid gland tumors to help in the differentiation between benign and malignant lesions. The CT findings of 22 patients with surgically proven parotid gland tumors were reviewed. Analysis was focused on the density and margin characteristics of the tumors, and the relationship between the tumor and surrounding structures. Those tumors were pleomorphic adenoma (n = 8), Warthin's tumor (n = 5), basal cell adenoma (n = 1), lipoma (n = 1), dermoid cyst (n = 1), adenoid cystic carcinoma (n = 2), mucoepidermoid carcinoma (n 1), epidermoid carcinoma (n = 1), and carcinoma in pleomorphic adenoma (n 1). Most of benign and malignant tumors were heterogeneous in density on contrast enhanced CT scans. In 5 of 6 malignant cases, the tumors had irregular or ill-defined margin and a tendancy to involve or cross the superficial layer of deep cervical fascia with obliteration of subcutaneous fat. Two malignant tumors invaded surrounding structures. Although the heterogeneous density of tumor is not a specific finding for malignancy at CT, following findings, such as, irregular or blurred margin of the lesion, the involvement of fascial plane, and the infiltration of surrounding structures may suggest the possibility of malignant parotid tumor

  17. The role of three-dimensional multidetector CT gastrography in the preoperative imaging of stomach cancer: Emphasis on detection and localization of the tumor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Woong; Shin, Sang Soo; Heo, Suk Hee; Lim, Hyo Soon; Park, Young Kyu; Jeong, Yong Yeon; Kang, Heoung Keun [Chonnam National University Medical School, Gwangju (Korea, Republic of); Lim, Nam Yeol [Dept. of Radiology, Chonnam National University Hospital, Gwangju (Korea, Republic of)

    2015-02-15

    Multidetector CT (MDCT) gastrography has been regarded as a promising technique for the preoperative imaging of gastric cancer. It has the ability to produce various three-dimensional (3D) images. Because 3D reconstruction images are more effective and intuitive for recognizing abnormal changes in the gastric folds and subtle mucosal nodularity than two-dimensional images, 3D MDCT gastrography can enhance the detection rate of early gastric cancer, which, in turn, contributes to the improvement of the accuracy of preoperative tumor (T) staging. In addition, shaded surface display and tissue transition projection images provide a global view of the stomach, with the exact location of gastric cancer, which may replace the need for barium studies. In this article, we discuss technical factors in producing high-quality MDCT gastrographic images and present cases demonstrating the usefulness of MDCT gastrography for the detection and T staging of gastric cancer while emphasizing the significance of preoperative localization of gastric cancer in terms of surgical margin.

  18. Hyperdensity liver tumor on plain CT

    Energy Technology Data Exchange (ETDEWEB)

    Hirota, Shozo; Hanaguri, Katsuro [Kochi Municipal Central Hospital (Japan); Shimizu, Masahumi; Sako, Masao; Harada, Yasushi

    1984-12-01

    Most liver tumors on plain CT have been recognized as low density or iso-density masses. Sometimes calcified high density masses were shown on plain CT in case of cysts or metastatic liver tumors. However, hyperdensity mass of the liver on CT, of which the density was a little higher than surrounding tissues, was very rare. Recently 7 patients with hyperdensity liver masses on plain CT were experienced: 6 hepatocellular carcinomas and 1 hepatic cavernous hemangioma. A single hyperdensity mass was shown in 4 patients, a hyperdensity mass of multiple hepatic tumors was shown in 2 patients, and some hyperdensity masses of multiple hepatic tumors were shown in 1 patient. Lesions are classified in 3 types according to the appearance of hyperdensity masses: diffuse hyperdensity all over the mass, ring like hyperdensity, creascent like hyperdensity. Intravenous contrast enhancement was performed in 2 patients: one with a primary hepatocellular carcinoma, and another with a hepatic cavernous hemangioma. In the former case the tumor margin had changed unclear, in the latter case the tumor was markedly enhanced. Our results revealed that hyperdensity liver tumors were divided into 2 types: One type, shown in a cavernous hemangioma with fatty liver, demonstrated relative hyperdensity due to lower density of the surrounding tissue. Another type, shown in 6 hepatocellular carcinomas, showed hyperdensity since the density of the tumor was hyperdensity relative to the surrounding tissue of the liver. It was suggested that the tumor with the latter type had been strongly probable of malignant one, and been recommended to receive further examination. Cause of hyperdensity was thought to be due to hemorrhage, though microcalcification could not be denyed. In Japan, no hyperdensity liver tumor had been reported partly due to a wide window width with which CT photographs were taken.

  19. Comparison of three approaches to delineate internal gross tumor volume based on four-dimensional CT simulation images of non-small-cell lung cancer

    International Nuclear Information System (INIS)

    Li Fengxiang; Li Jianbin; Zhang Yingjie; Shang Dongping; Liu Tonghai; Tian Shiyu; Xu Min; Ma Changsheng

    2011-01-01

    Objective: To compare positional and volumetric differences of internal gross tumor volume (IGTV) delineated separately by three approaches based on four-dimensional CT (4DCT) for the primary tumor of non-small cell lung cancer (NLCLC). Methods: Twenty-one patients with NLCLC underwent big bore 4DCT simulation scan of the thorax. IGTVs of the primary tumor of NSCLC were delineated using three approaches as followed: (1) the gross tumor volume (GTV) on each of the ten the respiratory phases of the 4DCT image set were delineated and the ten GTV were fused to produce IGTV 10 ; (2) the GTV delineated separately based on 0% and 50% phase were fused to produce IGTV EI+EE ; (3) the visible tumor on the MIP images were delineated to produce IGTV MIP . The position of the target center, the volume of target, the degree of inclusion (DI) and the matching index (MI) were compared reciprocally between IGTV 10 , IGTV EI+EE and IGTV MIP . Results: Average differences between the position of the center of IGTVs on direction of x, y and z axes were less than 1 mm, with no statistically significant difference. The volume of IGTV 10 was larger than that of IGTV EI+EE , the difference was statistically significant (t=2.37, P=0.028); the volume of IGTV 10 was larger than that of IGTV MIP , but the difference was not statistically significant (t=1.95, P=0.065). The ratio of IGTV EI+EE with IGTV 10 , IGTV MIP with IGTV 10 were 0.85±0.08 and 0.92±0.11, respectively. DI of IGTV EI+EE in IGTV 10 , IGTV MIP in IGTV 10 were 84.78% ± 8. 95% and 88.47% ±9.04%. MI between IGTV 10 and IGTV EI+EE , IGTV 10 and IGTV MIP were 0.85 ±0.09, 0.86±0.09, respectively. Conclusions: The center displacement of the IGTVs delineated separately by the three different techniques based on 4DCT images are not obvious; IGTV EI+EE and IGTV MIP can not replace IGTV 10 , however, IGTV MIP is more close to IGTV 10 comparing to IGTV EI+EE . The ratio of GTV EI+EE with IGTV 10 is correlated to the tumor motion

  20. Therapeutic efficacy and microSPECT/CT imaging of {sup 188}Re-DXR-liposome in a C26 murine colon carcinoma solid tumor model

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Y.-J.; Chang, C.-H.; Yu, C.-Y.; Chang, T.-J.; Chen, L.-C. [Institute of Nuclear Energy Research, Taoyuan, Taiwan (China); Chen, M.-H. [National Health Research Institutes, Miaoli, Taiwan (China); Lee, T.-W. [Institute of Nuclear Energy Research, Taoyuan, Taiwan (China); Ting Gann [National Health Research Institutes, Miaoli, Taiwan (China)], E-mail: gann.ting@msa.hinet.net

    2010-01-15

    Nanocarriers can selectively target cancer sites and carry payloads, thereby improving diagnostic and therapeutic effectiveness and reducing toxicity. The objective of this study was to investigate the therapeutic efficacy of a new co-delivery radiochemotherapeutics of {sup 188}Re-N,N-bis (2-mercaptoethyl)-N',N'-diethylethylenediamine (BMEDA)-labeled pegylated liposomal doxorubicin (DXR) ({sup 188}Re-DXR-liposome) in a C26 murine colon carcinoma solid tumor model. To evaluate the targeting and localization of {sup 188}Re-DXR-liposome in C26 murine tumor-bearing mice, biodistribution, microSPECT/CT imaging and pharmacokinetic studies were performed. The antitumor effect of {sup 188}Re-DXR-liposome was assessed by tumor growth inhibition, survival ratio and histopathological hematoxylin-eosin staining. The tumor target and localization of the nanoliposome delivery radiochemotherapeutics of {sup 188}Re-DXR-liposome were demonstrated in the biodistribution, pharmacokinetics and in vivo nuclear imaging studies. In the study on therapeutic efficacy, the tumor-bearing mice treated with bimodality radiochemotherapeutics of {sup 188}Re-DXR-liposome showed better mean tumor growth inhibition rate (MGI) and longer median survival time (MGI=0.048; 74 days) than those treated with radiotherapeutics of {sup 188}Re-liposome (MGI=0.134; 60 days) and chemotherapeutics of Lipo-Dox (MGI=0.413; 38 days). The synergistic tumor regression effect was observed with the combination index (CI) exceeding 1 (CI=1.145) for co-delivery radiochemotherapeutics of {sup 188}Re-DXR-liposome. Two (25%) of the mice treated with radiochemotherapeutics were completely cured after 120 days. The therapeutic efficacy of radiotherapeutics of {sup 188}Re-liposome and the synergistic effect of the combination radiochemotherapeutics of {sup 188}Re-DXR-liposome have been demonstrated in a C26 murine solid tumor animal model, which pointed to the potential benefit and promise of the co-delivery of

  1. Site Specific Discrete PEGylation of 124I-Labeled mCC49 Fab′ Fragments Improves Tumor MicroPET/CT Imaging in Mice

    Science.gov (United States)

    Ding, Haiming; Carlton, Michelle M.; Povoski, Stephen P.; Milum, Keisha; Kumar, Krishan; Kothandaraman, Shankaran; Hinkle, George H.; Colcher, David; Brody, Rich; Davis, Paul D.; Pokora, Alex; Phelps, Mitchell; Martin, Edward W.; Tweedle, Michael F.

    2014-01-01

    The tumor-associated glycoprotein-72 (TAG-72) antigen is highly overexpressed in various human adenocarcinomas and anti-TAG-72 monoclonal antibodies, and fragments are therefore useful as pharmaceutical targeting vectors. In this study, we investigated the effects of site-specific PEGylation with MW 2–4 kDa discrete, branched PEGylation reagents on mCC49 Fab′ (MW 50 kDa) via in vitro TAG72 binding, and in vivo blood clearance kinetics, biodistribution, and mouse tumor microPET/CT imaging. mCC49Fab′ (Fab′-NEM) was conjugated at a hinge region cysteine with maleimide-dPEG12-(dPEG24COOH)3 acid (Mal-dPEG-A), maleimide-dPEG12-(dPEG12COOH)3 acid (Mal-dPEG-B), or maleimide-dPEG12-(m-dPEG24)3 (Mal-dPEG-C), and then radiolabeled with iodine-124 (124I) in vitro radioligand binding assays and in vivo studies used TAG-72 expressing LS174T human colon carcinoma cells and xenograft mouse tumors. Conjugation of mCC49Fab′ with Mal-dPEG-A (Fab′-A) reduced the binding affinity of the non PEGylated Fab′ by 30%; however, in vivo, Fab′-A significantly lengthened the blood retention vs Fab′-NEM (47.5 vs 28.1%/ID at 1 h, 25.1 vs 8.4%/ID at 5 h, p Fab′-NEM by 70%, blood retention, microPET/CT imaging tumor signal intensity, and residual 72 h tumor concentration by 49% (3.83 ± 1.50 vs 1.97 ± 0.29%ID/g, p < 0.05) and 63% (3.83 ± 1.50 vs 1.42 ± 0.35%ID/g, p < 0.05), respectively. We conclude that remarkably subtle changes in the structure of the PEGylation reagent can create significantly altered biologic behavior. Further study is warranted of conjugates of the triple branched, negatively charged Mal-dPEG-A. PMID:24175669

  2. CT staging of renal pelvis tumor

    International Nuclear Information System (INIS)

    Yoon, Soo Woong; Cho, Kyoung Sik; Lee, Jong Hwa; Ham, Su Yeon; Won, Yeong Cheol; Ji, Eun Kyung; Choi, Seong Hun; Shin, Byung Suck

    1999-01-01

    To assess the value of computed tomography (CT) in the preoperative staging of transitional cell carcinoma (TCC) of the renal pelvis. We retrospectively evaluated the CT TNM staging of 38 patients with TCC of the renal pelvis who had undergone preoperative abdominal CT examination between January 1990 and January 1998. In CT staging for differentiation between early-stage (T0-2) and advanced-stage disease (T3-T4), three criteria were used, namely the presence or obliteration of the renal sinus fat layer, the smoothness or irregularity of margin between the tumor and renal parenchyma, and the presence or absence of hydronephrosis proximal to the tumor. CT staging was performed by two genitourinary radiologists blinded to the pathologic results, and was compared with pathologic staging. Pathologic results revealed 19 cases of early stage disease (T0=8, T1=9, T2=2) and 19 of advanced stage (T3=12, T4=7). Overall CT staging accuracy was 82%(31/38) ; four cases were overstaged and three were understaged. In early-stage disease, sensitivity and specificity were 79%, and 84%, and in advanced stage disease were 83% and 80%. Three of four overstaged cases showed hydronephrosis proximal to the tumor. In the second CT staging, using proximal hydronephrosis of the tumor as a criterion for early-stage disease, the sensitivity and specificity of early-stage disease were 95% and 75%, respectively, and the specificity of advanced-stage disease was 95%. When hydronephrosis proximal to a tumor was considered to be a sign of early stage disease, the CT staging of renal pelvic TCC was highly accurate

  3. TU-AB-202-07: A Novel Method for Registration of Mid-Treatment PET/CT Images Under Conditions of Tumor Regression for Patients with Locally Advanced Lung Cancers

    Energy Technology Data Exchange (ETDEWEB)

    Sharifi, Hoda [Department of Radiation Oncology, Henry Ford Health System, Detroit, MI (United States); Department of Physics, Oakland University, Rochester, MI (United States); Zhang, Hong; Jin, Jian-Yyue; Kong, Feng-Ming [Department of Radiation Oncology, GRU Cancer Center, Augusta GA (United States); Chetty, Indrin J [Department of Radiation Oncology, Henry Ford Health System, Detroit, MI (United States); Zhong, Hualiang

    2016-06-15

    Purpose: In PET-guided adaptive radiotherapy (RT), changes in the metabolic activity at individual voxels cannot be derived until the duringtreatment CT images are appropriately registered to pre-treatment CT images. However, deformable image registration (DIR) usually does not preserve tumor volume. This may induce errors when comparing to the target. The aim of this study was to develop a DIR-integrated mechanical modeling technique to track radiation-induced metabolic changes on PET images. Methods: Three patients with non-small cell lung cancer (NSCLC) were treated with adaptive radiotherapy under RTOG 1106. Two PET/CT image sets were acquired 2 weeks before RT and 18 fractions after the start of treatment. DIR was performed to register the during-RT CT to the pre-RT CT using a B-spline algorithm and the resultant displacements in the region of tumor were remodeled using a hybrid finite element method (FEM). Gross tumor volume (GTV) was delineated on the during-RT PET/CT image sets and deformed using the 3D deformation vector fields generated by the CT-based registrations. Metabolic tumor volume (MTV) was calculated using the pre- and during–RT image set. The quality of the PET mapping was evaluated based on the constancy of the mapped MTV and landmark comparison. Results: The B-spline-based registrations changed MTVs by 7.3%, 4.6% and −5.9% for the 3 patients and the correspondent changes for the hybrid FEM method −2.9%, 1% and 6.3%, respectively. Landmark comparisons were used to evaluate the Rigid, B-Spline, and hybrid FEM registrations with the mean errors of 10.1 ± 1.6 mm, 4.4 ± 0.4 mm, and 3.6 ± 0.4 mm for three patients. The hybrid FEM method outperforms the B-Spline-only registration for patients with tumor regression Conclusion: The hybrid FEM modeling technique improves the B-Spline registrations in tumor regions. This technique may help compare metabolic activities between two PET/CT images with regressing tumors. The author gratefully

  4. Imaging of pancreatic tumors

    International Nuclear Information System (INIS)

    Brambs, Hans-Juergen; Juchems, Markus

    2010-01-01

    Ductal adenocarcinoma is the most frequent solid tumor of the pancreas. This tumor has distinct features including early obstruction of the pancreatic duct, diminished enhancement after administration of contrast material due to desmoplastic growth, high propensity to infiltrate adjacent structures and to metastasize into the liver and the peritoneum. Hormone active endocrine tumors cause specific clinical symptoms. Imaging is aimed at localization of these hypervascular tumors. Non hormone active tumors are most frequently malignant and demonstrate very varying features. Cystic pancreatic tumors are increasingly detected by means of cross sectional imaging. Exact classification can be achieved with knowledge of the macropathology and considering clinical presentation as well as age and gender of the patients. (orig.)

  5. Diagnosis of intracranial mixed tumor with CT and MRI (report of 7 cases)

    International Nuclear Information System (INIS)

    Guan Changqun; Zhou Huaiwei; Xue Hongli; Zhang Yuzhong; Hu Lianyuan

    1998-01-01

    Purpose: To recognize the images of intracranial mixed tumor. Materials and methods: Seven cases were studied with CT and MRI. All were proved by pathology, including mixed tumor of meningioma with glioblastoma 2 cases, meningioma with pituitary tumor 2 cases, glioblastoma multiform with angioblastoma 1 cases, cholesteatoma with melanoma 1 case, and pituitary tumor with meningioma 1 case. The authors analysed the CT and MRI manifestations of intracranial mixed tumor retrospectively. Results: The CT and MRI manifestations of intracranial mixed tumor were exactly like meningioma, glioma, and hypophysoma, etc, therefore it was usually misdiagnosed the common tumor. Four cases intracranial mixed tumor displayed two kinds of characteristic CT and MRI manifestation on the same region of the same tumor in contrast with the clinic and pathologic change. Conclusion: There were no characteristic CT and MRI manifestations; the diagnosis should be made in combination with clinical information

  6. CT differentiation of solid ovarian tumor and uterine subserosal leiomyoma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyung Rae; Cho, Kyoung Sik [Asan Medical Center, Ulsan Univ. College of Medicine, Seoul (Korea, Republic of); Sohn, Chul Ho [Dongsan Medical Center, Keimyung Univ. College of Medicine, Taegu (Korea, Republic of); Ji, Eun Kyung [Bombit Hospital, Seoul (Korea, Republic of)

    1999-06-01

    On the basis of CT findings, to differentiate between solid ovarian tumor and uterine subserosal myoma. In eight surgically proven cases of solid ovarian tumor and in ten uterine subserosal myoma patients, contrast-enhanced CT images were obtained. Two genitourinary radiologists reviewed the findings with regard to degree of enhancement of the mass as compared with enhancement of uterine myometrium, thickening of round ligaments, visualization of normal ovaries, contour of the mass, and the presence of ascites in the pelvic cavity. Six of eight ovarian tumors but only two of ten uterine myomas were less enhanced than normal uterine myometrium (p<0.05). Pelvic ascites were seen in six of eight ovarian tumors, but in only one of ten uterine myomas (P<0.05). Three of 16 ovaries in ovarian tumor patients, but 12 of 20 ovaries in uterine myoma patients, were normal (p<0.05). Six of 16 round ligaments of the uterus in ovarian tumor patients, were thichened but 11 of 20 round ligaments in uterine myoma patients, were thickened (p>0.05). The contour of the mass was lobulated in two of eight ovarian tumor patients, but in five of ten uterine myoma patients (p>0.05). CT findings suggestive of solid ovarian tumor were less contrast enhancement of the mass than of normal uterine myometrium, pelvic ascites, and nonvisualization of normal ovary.

  7. CT findings of thymic tumors

    International Nuclear Information System (INIS)

    Chung, Ho Son; Lee, Sang Jin; Hwang, Mi Soo; Cho, Kil Ho; Chang, Jae Chun; Park, Bok Hwan

    1991-01-01

    A CT scan can make accurate diagnoses of most thymic masses by assessing their size, shape, and internal architecture and is especially effective in detecting pleural implants, mediastinal involvement, and pulmonary parenchymal invasion in malignant thymoma. The authors analyzed the CT findings of 10 histologically-proven thymic masses from 1983 to 1990 in Yeungnam University Hospital. There were 10 cases of thymic masses in the anterior mediastinum consisting of 6 benign, 3 invasive thymomas, and one thymolipoma, while myasthenia gravis was associated with 2 cases of benign thymomas and with one case of invasive thymomas. The CT findings of the benign thymomas (6 cases) were well-defined, bordered, round-or oval-shaped masses with a well-preserved fat plane between the thymic mass and mediastinal great vessels, with no evidence of pleural implants and lung parenchymal invasion. The CT findings of the invasive thymomas (3 cases) were irregular, marginated lobular masses with obliteration of the fat plane between the thymic mass and surrounding great vessels, with evidence of local invasion such as extension to A-P window and mass effect to bronchus. Irregular pleural thickening due to pleural metastasis, multiple metastatic lung parenchymal nodules, and multiple mediastinal lymph node enlargement were also seen in the invasive thymomas. One case of thymolipoma showed an approximately 20cm-size, well-defined fat density mass containing internal septations

  8. CT findings of thymic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Ho Son; Lee, Sang Jin; Hwang, Mi Soo; Cho, Kil Ho; Chang, Jae Chun; Park, Bok Hwan [College of Medicine, Yeungnam University, Daegu (Korea, Republic of)

    1991-05-15

    A CT scan can make accurate diagnoses of most thymic masses by assessing their size, shape, and internal architecture and is especially effective in detecting pleural implants, mediastinal involvement, and pulmonary parenchymal invasion in malignant thymoma. The authors analyzed the CT findings of 10 histologically-proven thymic masses from 1983 to 1990 in Yeungnam University Hospital. There were 10 cases of thymic masses in the anterior mediastinum consisting of 6 benign, 3 invasive thymomas, and one thymolipoma, while myasthenia gravis was associated with 2 cases of benign thymomas and with one case of invasive thymomas. The CT findings of the benign thymomas (6 cases) were well-defined, bordered, round-or oval-shaped masses with a well-preserved fat plane between the thymic mass and mediastinal great vessels, with no evidence of pleural implants and lung parenchymal invasion. The CT findings of the invasive thymomas (3 cases) were irregular, marginated lobular masses with obliteration of the fat plane between the thymic mass and surrounding great vessels, with evidence of local invasion such as extension to A-P window and mass effect to bronchus. Irregular pleural thickening due to pleural metastasis, multiple metastatic lung parenchymal nodules, and multiple mediastinal lymph node enlargement were also seen in the invasive thymomas. One case of thymolipoma showed an approximately 20cm-size, well-defined fat density mass containing internal septations.

  9. CT and MRI findings of 4th ventricular tumors

    International Nuclear Information System (INIS)

    Kim, Taek Geun; Ro, Hee Jeong; Byun, Jae Young; Lee, Han Jin; Chung, Myung Hee; Choi, Kyu Ho; Shinn, Kyung Sub

    1994-01-01

    The purpose of our study is to evaluate characteristic features of 4th ventricular tumors in CT and MRI. Pathologically proved 9 patients with 4th ventricular tumor were examined by CT and/or MRI. 4th ventricular tumors were ependymoma(4 cases), medulloblastoma(2 case), choroid plexus papilloma(2 cases), and oligodendroglioma(1 cases). Include in our study were only those mass lesions that were located at surgery predominantly within 4th ventricle with or without ventricular expansion. The origin of 4th ventricular tumor was the roof (ependymoma 3 cases, medulloblastoma 2 cases), the floor (ependymoma 1 cases), and the undetermined(remaining 3 case). On MRI, all tumors were hypointense except ependymoma (3 cases) showing isointensity on T1WI. All tumors were hypointense on PDWI and T2WI. On Gd-DTPA enhanced T1WI, strong enhancement was seen in all but ependymoma(1 cases) which showed mild enhancement. On CT, as compared with MR images, various density on precontrast and postcontrast images were seen. Calcification was seen in choroid plexus papilloma(1 caes) and oligodendroglioma(1 cases). Hydrocephalus is seen in all cases except ependymoma(2 cases) and oligodendroglioma(1 case). Hemorrhage within tumor was present only in ependymoma(2 cases). Cystic change or necrosis of tumor was seen in ependymoma(3 cases), choroid plexus papilloma(1 case), and oligodendroglioma(1 case). Peritumoral edema was seen in medulloblastoma(1 case). Extension through the foramen Luschka and the Megendie was seen in ependymoma (2 cases), choroid plexus(2 cases), and medulloblastoma (1 case). Seeing along the CSF pathway was seen only in ependymoma(2 case). The results od our study may suggest that specific diagnosis of 4th ventricular tumor can be suggested preoperatively by analysing the origin in 4th ventricle, difference of CT density or MRI signal intensity, presence of extension or seeding through cerebrospinal fluid of the lesion

  10. CT and MRI of germ-cell tumors with metastasis or multi-located tumors

    International Nuclear Information System (INIS)

    Miyagami, Mitsusuke; Tazoe, Makoto; Tsubokawa, Takashi

    1989-01-01

    Twenty-seven cases of germ-cell tumors were examined with a CT scan in our clinic. In the 11 cases of metastasis or multi-localized tumors, the CT findings were studied in connection with the MRI findings. There were 6 cases of germ-cell tumors which had broad infiltrating tumors with multiple lesions on first admission. Their tumor sites were different from that in cases of malignant glioma, being frequently localized in the pineal and/or the suprasellar region, on the wall of the third and/or lateral ventricle, and in the region of the basal ganglia. Five of the cases of germ-cell tumors had metastasis with various patterns connected to a remote area - that is, to spinal cords, to the ventricular wall and basal cistern of the brain stem by CSF dissemination, to a lung by hematogeneous metastasis, and to the peritoneal wall or organs by a V-P shunt. The CT findings of germ-cell tumors were correlated mainly with the results of the histological diagnosis; they were found not to differ with the tumor site. The germinoma in the suprasellar region had less calcification than in the pineal region. Cysts, calcification, and an enlargement of the lateral ventricle on the tumor side were frequently seen in the germinoma of the basal ganglia. On the MRI of 5 cases of germinoma, the T 1 -weighted image revealed a slightly low or iso signal intensity, while the T 2 -weighted image showed a high signal intensity. In the case of multiple tumor lesions, some cases demonstrated different CT findings and radiosensitivities for each tumor. The possibility of a multicentric origin for the tumors is thus suggested in some cases of germ-cell tumors. (author)

  11. Analysis on CT features of tumor-like gastric schwannomas

    International Nuclear Information System (INIS)

    Zhang Yu; Chen Jie

    2011-01-01

    Objective: To analyze CT imaging features of tumor-like gastric schwannomas. Methods: Ten patients with gastric schwannomas were retrospectively analyzed. All were scanned with pre-and pro-enhanced CT. Analysis of the CT findings included evaluation of the volume, number, location, contour, growth pattern, border, enhancement pattern, and enhancement grade as well as the presence of surface dimpling, integrity of overlying mucosa. All cases were confirmed by pathology. Results: In every case, simple tumor was present. The largest was about 5.7 cm in the diameter, the smallest was 2.3 cm. All tumors were round or oval, and one tumor was slightly lobulated. Endoluminal growth pattern was defined in two cases, exoluminal growth pattern was defined in one case, and a mixed growth pattern was noted in the rest. The borders of tumors were clear. In arterial phase, no visible enhancement was present in eight cases and mild enhancement in two cases. All cases were constantly enhanced in portal phase. Superficial ulcers were present in four cases. Conclusion: CT findings of tumor-like gastric schwannomas are distinctive to a certain degree. It can be used to guide clinical therapy. (authors)

  12. Biodistribution of 125I-labeled anti-endoglin antibody using SPECT/CT imaging: Impact of in vivo deiodination on tumor accumulation in mice

    International Nuclear Information System (INIS)

    Karmani, Linda; Levêque, Philippe; Bouzin, Caroline; Bol, Anne; Dieu, Marc; Walrand, Stephan; Vander Borght, Thierry; Feron, Olivier; Grégoire, Vincent; Bonifazi, Davide

    2016-01-01

    Introduction: Radiolabeled antibodies directed against endoglin (CD105) are promising tools for imaging and antiangiogenic cancer therapy. To validate iodinated antibodies as reliable tracers, we investigated the influence of the radiolabeling method (direct or indirect) on their in vivo stability. Methods: Anti-CD105 mAbs were radioiodinated directly using chloramine-T ( 125 I-anti-CD105-mAbs) or indirectly using D-KRYRR peptide as a linker ( 125 I-KRYRR-anti-CD105-mAbs). The biodistribution was studied in B16 tumor-bearing mice via SPECT/CT imaging. Results: Radioiodinated mAbs were stable in vitro. In vivo, thyroid showed the most important increase of uptake after 24 h for 125 I-anti-CD105-mAbs (91.9 ± 4.0%ID/ml) versus 125 I-KRYRR-anti-CD105-mAbs (4.4 ± 0.6%ID/ml). Tumor uptake of 125 I-anti-CD105-mAbs (0.9 ± 0.3%ID/ml) was significantly lower than that of 125 I-KRYRR-anti-CD105-mAbs (4.7 ± 0.2%ID/ml). Conclusions: An accurate characterization of the in vivo stability of radioiodinated mAbs and the choice of an appropriate method for the radioiodination are required, especially for novel targets. The indirect radioiodination of internalizing anti-CD105 mAbs leads to more stable tracer by decreasing in vivo deiodination and improves the tumor retention of radioiodinated mAbs. Advances in knowledge and implications for patient care: To date, the only antiangiogenic antibody approved for clinical indications is bevacizumab. There is a need to develop more antibodies that have targets highly expressed on tumor endothelium. CD105 represents a promising marker of angiogenesis, but its therapeutic relevance in cancer needs to be further investigated. In this context, this study suggests the potential use of indirectly iodinated anti-CD105 mAbs for tumor imaging and for therapeutic purposes.

  13. CT Features of pseudo tumoral bronchopulmonary tuberculosis

    International Nuclear Information System (INIS)

    Zidi, A.; Hantoux, S.; Mestiri, I.; Ben Miled-Mrad, K.

    2006-01-01

    Pulmonary tuberculosis may at times simulate lung carcinoma on bronchoscopic examination or imaging studies. Diagnosis can be delayed and lead to surgical resection. Based on review of 25 cases, the different CT features are reviewed. (author)

  14. Impact of 4D-(18)FDG-PET/CT imaging on target volume delineation in SBRT patients with central versus peripheral lung tumors. Multi-reader comparative study.

    Science.gov (United States)

    Chirindel, Alin; Adebahr, Sonja; Schuster, Daniel; Schimek-Jasch, Tanja; Schanne, Daniel H; Nemer, Ursula; Mix, Michael; Meyer, Philipp; Grosu, Anca-Ligia; Brunner, Thomas; Nestle, Ursula

    2015-06-01

    Evaluation of the effect of co-registered 4D-(18)FDG-PET/CT for SBRT target delineation in patients with central versus peripheral lung tumors. Analysis of internal target volume (ITV) delineation of central and peripheral lung lesions in 21 SBRT-patients. Manual delineation was performed by 4 observers in 2 contouring phases: on respiratory gated 4DCT with diagnostic 3DPET available aside (CT-ITV) and on co-registered 4DPET/CT (PET/CT-ITV). Comparative analysis of volumes and inter-reader agreement. 11 cases of peripheral and 10 central lesions were evaluated. In peripheral lesions, average CT-ITV was 6.2 cm(3) and PET/CT-ITV 8.6 cm(3), resembling a mean change in hypothetical radius of 2 mm. For both CT-ITVs and PET/CT-ITVs inter reader agreement was good and unchanged (0.733 and 0.716; p=0.58). All PET/CT-ITVs stayed within the PTVs derived from CT-ITVs. In central lesions, average CT-ITVs were 42.1 cm(3), PET/CT-ITVs 44.2 cm(3), without significant overall volume changes. Inter-reader agreement improved significantly (0.665 and 0.750; p1 ml in average for all observers. The addition of co-registered 4DPET data to 4DCT based target volume delineation for SBRT of centrally located lung tumors increases the inter-observer agreement and may help to avoid geographic misses. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. CT imaging features of anaplastic thyroid carcinoma

    International Nuclear Information System (INIS)

    Shi Zhenshan; You Ruixiong; Cao Dairong; Li Yueming; Zhuang Qian

    2013-01-01

    Objective: To investigate the CT characteristics of anaplastic thyroid carcinoma and evaluate the diagnostic value of CT in this disease. Methods: The CT findings of 10 patients with pathologically proved anaplastic thyroid carcinoma were retrospectively reviewed. The patients included 7 females and 3 males. Their age ranged from 25.0 to 78 years with median of 61 years. Multi-slices plain and post contrast CT scans were performed in all patients. Results: Unilateral thyroid was involved in 6 patients. Unilateral thyroid and thyroid isthmus were both involved in 2 patients due to big size. Bilateral thyroid were involved in 2 patients. The maximum diameter of anaplastic thyroid carcinoma ranged from 2.9-12.8 cm with mean of (4.5 ± 1.4) cm. All lesions demonstrated unclear margins and envelope invasion. The densities of all lesions were heterogeneous and obvious necrosis areas were noted on precontrast images. Seven lesions showed varied calcifications, and coarse granular calcifications were found in 5 lesions among them. All lesions showed remarkable heterogenous enhancement on post-contrast CT. The CT value of solid portion of the tumor increased 40 HU after contrast media administration. The ratios of CT value which comparing of the tumor with contralateral sternocleidomastoid muscle were 0.69-0.82 (0.76 ± 0.18) and 1.25-1.41 (1.33 ± 0.28) on pre and post CT, respectively. Enlarged cervical lymph nodes were found in 6 cases (60.0%). It showed obvious homogeneous enhancement or irregular ring-like enhancement on post-contrast images and dot calcifications were seen in 1 case. Conclusions: Relative larger single thyroid masses with coarse granular calcifications, necrosis,envelope invasion, remarkable heterogeneous enhancing and enlarged lymph nodes on CT are suggestive of anaplastic thyroid carcinoma. (authors)

  16. Dynamic CT myocardial perfusion imaging

    International Nuclear Information System (INIS)

    Caruso, Damiano; Eid, Marwen; Schoepf, U. Joseph; Jin, Kwang Nam; Varga-Szemes, Akos; Tesche, Christian; Mangold, Stefanie

    2016-01-01

    Highlights: • CT myocardial perfusion provides functional assessment of the myocardium. • CCTA is limited in determining the hemodynamic significance of coronary stenosis. • CT-MPI can accurately detect hemodynamically significant coronary artery stenosis. - Abstract: Non-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT based technologies. Coronary CT angiography has been shown to reliably assess coronary anatomy and detect high risk coronary artery disease. However, this technique is limited to anatomical assessment, thus non-invasive techniques for functional assessment of the heart are necessary. CT myocardial perfusion is a new CT based technique that provides functional assessment of the myocardium and allows for a comprehensive assessment of coronary artery disease with a single modality when combined with CTA. This review aims to discuss dynamic CT myocardial perfusion as a new technique in the assessment of CAD.

  17. Dynamic CT myocardial perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncological and Pathological Sciences, University of Rome “Sapienza”, Latina (Italy); Eid, Marwen [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States); Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul (Korea, Republic of); Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Mangold, Stefanie [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Tuebingen (Germany); and others

    2016-10-15

    Highlights: • CT myocardial perfusion provides functional assessment of the myocardium. • CCTA is limited in determining the hemodynamic significance of coronary stenosis. • CT-MPI can accurately detect hemodynamically significant coronary artery stenosis. - Abstract: Non-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT based technologies. Coronary CT angiography has been shown to reliably assess coronary anatomy and detect high risk coronary artery disease. However, this technique is limited to anatomical assessment, thus non-invasive techniques for functional assessment of the heart are necessary. CT myocardial perfusion is a new CT based technique that provides functional assessment of the myocardium and allows for a comprehensive assessment of coronary artery disease with a single modality when combined with CTA. This review aims to discuss dynamic CT myocardial perfusion as a new technique in the assessment of CAD.

  18. Preoperative CT prediction for Masaoka staging of thymic epithelial tumor

    International Nuclear Information System (INIS)

    Feng Zhan; Huang Zhen; Zhang Liang

    2013-01-01

    Objective: To discuss the value of CT prognosis on the Masaoka staging system of thymic epithelial tumors (TET) before surgical resection. Methods: The CT images of 102 patients with TET proved by surgery and pathology were reviewed retrospectively. The TET were reclassified according to Masaoka stage system. The size, homogeneity, sharp, contour, infiltration of surrounding tissue, and metastasis on CT were analyzed with Logistic analysis. The diagnostic value was also evaluated with a ROC curve. Results: Masaoka pathologic stages were stage Ⅰ for 36 (35.3 %), stage Ⅱ for 27 (26.5 %), stage Ⅲ for 30 (29.4 %), and stage Ⅳ for 9 (8.8 %). A multivariable Logistic regression model showed that TET with larger size of tumor (20/35, P = 0.0371, OR = 4.539), irregular or lobulated tumor contour (26/42, P = 0.0230, OR = 4.870), heterogeneous (21/33, P = 0.0154, OR = 6.020), infiltration of surrounding fat (25/32, P = 0.0019, OR = 14.005), and pleural seeding (11/11, P = 0.0032, OR = 36.153) were more likely to have stage Ⅲ or Ⅳ disease. The area under ROC curve was 0.940. Conclusions: The tumor CT imaging features can differentiate between stage Ⅰ, Ⅱ and stage Ⅲ, Ⅳ disease. This helps identified patients more likely to benefit from neoadjuvant therapy. (authors)

  19. CT and MR imaging characteristics of infantile hepatic hemangioendothelioma

    International Nuclear Information System (INIS)

    Feng Shiting; Chan Tao; Ching, A.S.C.; Sun Canhui; Guo Huanyi; Fan Miao; Meng Quanfei; Li Ziping

    2010-01-01

    Aim: This study aims to analyze computed tomography (CT) and magnetic resonance (MR) imaging features of infantile hepatic hemangioendotheliomas before and after treatment. Materials and methods: CT and MR examinations of seven infants with biopsy proven hepatic hemangioendotheliomas were retrospectively analyzed. The distribution, number, size, imaging appearance, enhancement pattern and post-treatment changes of the tumors were evaluated. Results: A total of 153 hepatic hemangioendotheliomas were detected on CT (111) and MR (42) imaging. In six infants, 109/111 (98.2%) tumors were hypodense and 2/111 (1.8%) lesions contained calcification on unenhanced CT. On MR imaging, all 42 lesions in one infant were heterogeneously T1-hypointense and T2-hyperintense compared to the normal liver parenchyma. Contrast-enhanced CT and MRI showed peripheral rim (51.6%), uniform (48.4%), fibrillary (33.3%), and nodular (28.8%) contrast enhancement in the hepatic arterial phase. Homogeneous (100%), rim (98.2%) and mixed enhancement patterns were noted in tumors 2.0 cm and 1.0-2.0 cm in diameter respectively in the hepatic arterial phase. In three patients who underwent steroid therapy, follow-up CT examination demonstrated tumor size reduction and increased intra-tumoral calcification in two patients. Conclusion: Infantile hepatic hemangioendotheliomas show some typical imaging features and size-dependent pattern of contrast enhancement on CT and MR imaging, which allow accurate imaging diagnosis and post-treatment evaluation.

  20. Clinical Application of colored three-dimensional CT (3D-CT) for brain tumors using helical scanning CT (HES-CT)

    International Nuclear Information System (INIS)

    Ogura, Yuko; Katada, Kazuhiro; Fujisawa, Kazuhisa; Imai, Fumihiro; Kawase, Tsukasa; Kamei, Yoshifumi; Kanno, Tetsuo; Takeshita, Gen; Koga, Sukehiko

    1995-01-01

    We applied colored three-dimensional CT (colored 3D-CT) images to distinguish brain tumors from the surrounding vascular and bony structures using a work station system and helical scanning CT (HES-CT). CT scanners with a slip-ring system were employed (TCT-900S and X vigor). A slice thickness of 2 mm and bed speed of 2 mm/s were used. The volume of contrast medium injected was 60 to 70 ml. Four to 8 colors were used for the tissue segmentation on the workstation system (xtension) using the data transferred from HES-CT. Tissue segmentation succeeded on the colored 3D-CT images in all 13 cases. The relationship between the tumors and the surrounding structures were easily recognized. The technique was useful to simulate operative fields, because deep structures could be visualized by cutting and drilling the colored 3D-CT volumetric data. On the basis of our findings, we suggest that colored 3D-CT images should be used as a supplementary aid for preoperative simulation. (author)

  1. Additional value of hybrid SPECT/CT systems in neuroendocrine tumors, adrenal tumors, pheochromocytomas and paragangliomas.

    Science.gov (United States)

    Wong, K K; Chondrogiannis, S; Fuster, D; Ruiz, C; Marzola, M C; Giammarile, F; Colletti, P M; Rubello, D

    The aim of this review was to evaluate the potential advantages of SPECT/CT hybrid imaging in the management of neuroendocrine tumors, adrenal tumors, pheochromocytomas and paragangliomas. From the collected data, the superiority of fused images was observed as providing both functional/molecular and morphological imaging compared to planar imaging. This provided an improvement in diagnostic imaging, with significant advantages as regards: (1) precise locating of the lesions; (2) an improvement in characterization of the findings, resulting higher specificity, improved sensitivity, and overall greater accuracy, (3) additional anatomical information derived from the CT component; (4) CT-based attenuation correction and potential for volumetric dosimetry calculations, and (5) improvement on the impact on patient management (e.g. in better defining treatment plans, in shortening surgical operating times). It can be concluded that SPECT/CT hybrid imaging provides the nuclear medicine physician with a powerful imaging modality in comparison to planar imaging, providing essential information about the location of lesions, and high quality homogeneous images. Copyright © 2016 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

  2. The role of CT in diagnosing small hepatic tumors

    International Nuclear Information System (INIS)

    Usuki, Noriaki; Daikokuya, Hideo; Fukuda, Haruyuki; Saiwai, Shigeo; Nakajima, Hideyuki; Miyamoto, Takeshi; Kudo, Masatoshi

    1992-01-01

    Twenty-seven cases of small hepatic tumors were examined by MRI and CT (ICT). MRI was more sensitive than plain and contrast CT. But ICT could detect more small lesions than MRI. CT is not more superior modality than MRI untill ICT is performed. It is concluded ICT should be done when diagnosing small hepatic tumors by CT. (author)

  3. CT findings of malignant nasal cavity tumors

    International Nuclear Information System (INIS)

    Ku, Young Mi; Chun, Kyung Ah; Choi, Kyu Ho; Yu, Won Jong; Kim, Young Joo; Kim, Sung Hoon; Park, Seog Hee; Shinn, Kyung Sub

    1997-01-01

    To evaluate the CT findings of malignant nasal cavity tumors. Retrospective analysis was performed on 20 patients with pathologically-proven malignant nasal cavity tumors. Using CT, we analysed their location, extent of bone destruction and of involvement of adjacent structures, and enhancing pattern. A total of 20 cases included nine squamous cell carcinomas, three olfactory neuroblastomas, three lymphomas, two polymorphic reticulosis, one adenoid cystic carcinoma, one undifferentiated carcinoma and one metastasis from renal cell carcinoma. All cases except one adenoid cystic carcinoma and one squamous cell carcinoma revealed bone destruction or erosion. Aggressive bone destruction and irregular enhancement were seen in eight cases of squamous cell carcinoma, seven cases of which showed involvement of the adjacent paranasal sinuses, nasopharynx, and orbit. Olfactory neuroblastomas were centered in the superior nasal cavity and the adjacent ethmoid sinus, and erosion or destruction of the cribriform plate had occurred. Lymphomas showed bilateral involvement, with uniform contrast enhancement. Polymorphic reticuloses showed perforation or erosion of the nasal septum, with bilateral involvement of the nasal cavity. The location, presence of bone destruction, involvement of adjacent structures, and enhancement pattern of tumor on CT can be helpful for the differential diagnosis of malignant nasal cavity tumors

  4. FDG PET/CT对骨及软组织肿瘤诊断和疗效评价的应用%FDG PET/CT imaging in the diagnosis and efficacy evaluation for bone and soft tissue tumors

    Institute of Scientific and Technical Information of China (English)

    刘健; 赵涛; 吕杰; 孙波; 张鹏

    2011-01-01

    Objective To assess the clinical value of FDG PET/CT imaging in the diagnosis and efficacy evaluation for bone and soft tissue tumors.Methods The FDG PET/CT images of 48 patients diagnosed with bone and soft tissue tumors were retrospectively analyzed.These FDG PET/CT images were analyzed in order to differentially diagnose the tumors to be benign or malignant, and to confirm whether there was recurrence, distal metastasis and surrounding invasion or not.Besides, comparative analysis was done between the FDG PET/CT imaging and the CT imaging.Results For FDG PET/CT imaging in the diagnosis for bone and soft tissue tumors, the rate of sensitivity was10O% (7/7), and the rate of specificity was 80% (4/5).According to the monitoring results of recurrence and residual,both the post-operative rate of sensitivity and the post-operative rate of specificity were 1O0%.Extra 35 metastases were detected by the PET/CT imaging, and the other 12 pulmonary metastases were found by the CT imaging.Conclusions FDG PET/CT imaging in the diagnosis for bone and soft tissue tumors is better than the routine imaging.It can accurately detect the recurrence of tumors in the early stage, and find extra metastasis (except pulmonary metastasis).Therefore, it can assist the treatment and diagnosis against tumors.%目的 探讨FDG PET/CT显像诊断骨或软组织肿瘤和术后疗效评价的价值.方法 回顾性分析48例已证实的骨及软组织肿瘤患者的FDG PET/CT显像结果,以鉴别诊断肿瘤的良恶性,是否复发、有无其他转移及周围侵犯,并与同机CT对比分析.结果 FDG PET/CT显像诊断骨及软组织肿瘤灵敏度为100%(7/7),特异性为80%(4/5);监测术后复发(残留)的灵敏度和特异性均为100%;通过PET/CT显像多发现转移灶35处,对于肺部12个转移灶,有赖于同机CT.结论 FDG PET/CT显像对骨及软组织肿瘤的诊断优于常规影像检查,可早期准确判断肿瘤复发,同时发现更多转移灶(肺转移除

  5. Imaging of urinary bladder tumors

    International Nuclear Information System (INIS)

    Hadjidekov, G.

    2015-01-01

    Full text: Primary bladder neoplasms account for 2%-6% of all tumors, with urinary bladder cancer ranked as the fourth most common cancer in males. Transitional cell carcinoma (TCC) is the most common subtype of urothelial tumour accounting for approximately 90% of all urothelial cancers. It is typically observed in men aged 50-70 years with history of smoking or occupational exposure to carcinogens. Most urothelial neoplasms are low-grade papillary tumors, with high incidence of recurrence, requires rigorous follow-up but have a relatively good prognosis. Other bladder neoplasm include squamous cell carcinoma accounts for 2%-15% mainly according to geographic location; adenocarcinoma - less than 2% /both occurring in the context of chronic bladder infection and irritation/; mesenchymal tumors in 5%, with the most common examples being rhabdomyosarcoma in children and leiomyosarcoma in adults. More rare mesenchymal tumors include paraganglioma, lymphoma, leiomyoma and solitary fibrous tumor which have no specific typical imaging findings to be differentiated. Multidetector computed tomography urography is an efficient tool for diagnosis and follow-up in patients with transitional cell carcinoma and it can be considered the primary radiologic method for detection, staging and assessment of the entire urothelium regarding the multicentric nature of TCC. MRI is rapidly expanding modality of choice especially in locally staging the tumor and in controversies. Accurate TNM staging is primordial in choosing treatment and prognosis for patients with bladder carcinoma. Correct interpretation and classification of the tumour is helpful for the urologists to determine further management in these cases. The learning objectives of the presentation are: to illustrate the spectrum of CT and MRI findings and to assess their clinical value in patients with transitional cell carcinoma and some other bladder neoplasm; to discuss the TNM staging based on the imaging findings; to be

  6. CT findings of skull tumors forming subcutaneous masses

    International Nuclear Information System (INIS)

    Niida, Hirohito; Takeda, Norio; Onda, Kiyoshi; Tanaka, Ryuichi

    1991-01-01

    Some characteristics of CT findings in 27 patients with skull tumors forming subcutaneous tumors were studied. There were sixteen metastatic skull tumors, six primary skull tumors, and five meningiomas. A CT scan was found to be helpful in the diagnosis of the lesions. Especially, bone-window CT images proved very sensitive in the detection of destructive and permeative lesions of the skull. In 19 of the 27 cases, some lytic lesions were observed. In all cases with skull metastasis from carcinomas, a complete osteolytic change of the skull was observed. Furthermore, all of the metastatic tumors from thyroid carcinoma showed well circumscribed and homogeneously enhanced lesions, in contrast with the other metastatic carcinomas, which usually showed heterogeneously enhanced lesions with irregular margins. Osteoblastic changes were characteristically observed in all cases of meningiomas, osteosarcoma, and chondrosarcoma. Meningiomas were located mainly in the intracranial region and extended extracranially. In one case of malignant lymphoma, one of a neuroblastoma, and one of leukemia, there was little or no gross cortical bone change, despite a large mass. (author)

  7. The role of CT in diagnosing small hepatic tumors; Usefulness of table incremental dynamic CT (ICT)

    Energy Technology Data Exchange (ETDEWEB)

    Usuki, Noriaki; Daikokuya, Hideo; Fukuda, Haruyuki; Saiwai, Shigeo; Nakajima, Hideyuki; Miyamoto, Takeshi; Kudo, Masatoshi (Kobe General Hospital, Hyogo (Japan))

    1992-11-01

    Twenty-seven cases of small hepatic tumors were examined by MRI and CT (ICT). MRI was more sensitive than plain and contrast CT. But ICT could detect more small lesions than MRI. CT is not more superior modality than MRI untill ICT is performed. It is concluded ICT should be done when diagnosing small hepatic tumors by CT. (author).

  8. Sequential computed tomographic imaging of a transplantable rabbit brain tumor

    International Nuclear Information System (INIS)

    Kumar, A.J.; Rosenbaum, A.E.; Beck, T.J.; Ahn, H.S.; Anderson, J.

    1986-01-01

    The accuracy of CT imaging in evaluating VX-2 tumor growth in the rabbit brain was assessed. CT scanning was performed in 5 outbred New Zealand white male rabbits before and at 4, 7, 9 and 13 (in 3 animals) days after surgical implantation of 3 x 10 5 viable VX-2 tumor cells in the frontoparietal lobes. The CT studies were correlated with gross pathology in each. The tumor was visualized with CT in all 5 rabbits by the 9th day post implantation when the tumor ranged in size from 4-6 x 3-4 x 2-3 mm. Between the 9th and 13th day, the tumor increased 6-fold in two rabbits and 12-fold in the third rabbit. CT is a useful technique to evaluate brain tumor growth in this model and should be valuable in documenting the efficacy of chemotherapy on tumor growth. (orig.)

  9. Malignant granular cell tumor of the abdominal wall mimicking desmoid tumor: A case report with CT imaging findings and literature review

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Je Hong; Ahn, Sung Eun; Lee, Dong Ho; Park, Seong Jin; Moon, Sung Kyoung; Lim, Joo Won [Dept. Radiology, Kyung Hee University Hospital, Kyung Hee University School of Medicine, Seoul (Korea, Republic of)

    2016-08-15

    Granular cell tumors (GCTs) are extremely rare mesenchymal neoplasms of Schwann cell origin. Malignant GCTs (MGCTs) comprise 0.5-2% of all GCTs. In the present report, we describe a case of a 66-year-old man with MGCT of the abdominal wall. The patient visited our hospital due to a recently growing palpable soft tissue mass in the abdominal wall. Computed tomography scan revealed a 4.3 × 4.1 × 2.9 cm sized mass arising from the left abdominal wall, which was contemplated as a desmoid tumor before surgical excision. Histopathological examination confirmed MGCT.

  10. Evaluation of thymic tumors with 18F-FDG PET-CT - A pictorial review

    International Nuclear Information System (INIS)

    Sharma, Punit; Singhal, Abhinav; Bal, Chandrasekhar; Malhotra, Arun; Kumar, Rakesh; Kumar, Arvind

    2013-01-01

    Thymic tumors represent a broad spectrum of neoplastic disorders and pose considerable diagnostic difficulties. A non-invasive imaging study to determine the nature of thymic lesions can have significant impact on management of such tumors. 18F-flurorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) has shown promising results in characterization of thymic tumors. The objective of this article is to provide an illustrative tutorial highlighting the clinical utility of 18F-FDG PET-CT imaging in patients with thymic tumors. We have pictorially depicted the 18F-FDG PET-CT salient imaging characteristics of various thymic tumors, both epithelial and non-epithelial. Also discussed is the dynamic physiology of thymus gland which is to be kept in mind when evaluating thymic pathology on 18F-FDG PET-CT, as it can lead to interpretative pitfalls

  11. 3D-CT imaging processing for qualitative and quantitative analysis of maxillofacial cysts and tumors Processamento de imagens em 3D-TC para análise qualitativa e quantitativa de cistos e tumores maxilo-faciais

    Directory of Open Access Journals (Sweden)

    Marcelo de Gusmão Paraiso Cavalcanti

    2002-09-01

    Full Text Available The objective of this study was to evaluate spiral-computed tomography (3D-CT images of 20 patients presenting with cysts and tumors in the maxillofacial complex, in order to compare the surface and volume techniques of image rendering. The qualitative and quantitative appraisal indicated that the volume technique allowed a more precise and accurate observation than the surface method. On the average, the measurements obtained by means of the 3D volume-rendering technique were 6.28% higher than those obtained by means of the surface method. The sensitivity of the 3D surface technique was lower than that of the 3D volume technique for all conditions stipulated in the diagnosis and evaluation of lesions. We concluded that the 3D-CT volume rendering technique was more reproducible and sensitive than the 3D-CT surface method, in the diagnosis, treatment planning and evaluation of maxillofacial lesions, especially those with intra-osseous involvement.O presente trabalho consiste em um estudo associativo e comparativo entre as técnicas de superfície e volume para a reconstrução de imagens em três dimensões (3D utilizando tomografia computadorizada (TC. Foram realizadas tomografias computadorizadas em espiral de 20 pacientes com cistos e tumores do complexo maxilo-facial para análise qualitativa e quantitativa, utilizando métodos de superfície e de volume em 3D. A comparação interexaminadores apresentou erro padrão percentual menos elevado para a técnica de volume (1,94% que para a técnica de superfície (4,38%, indicando a maior reprodutibilidade do primeiro método. As medidas obtidas pela técnica de volume foram em média 6,28% mais elevadas que as medidas obtidas pela técnica de superfície. A técnica de volume apresentou sensibilidade mais elevada que a técnica de superfície na identificação das lesões do complexo maxilo-facial. A técnica de volume em 3D-TC, utilizando a metodologia da computação gráfica, apresentou maior

  12. Brain tumor and CT, 1. Relationship between the consistency of a brain tumor and the CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, N.; Katada, K.; Shinomiya, Y.; Sano, H.; Kanno, T. (Fujita Gakuen Univ., School of Medicine, Toyoake, Aichi (Japan))

    1981-08-01

    It is very important for a neurosurgeon to know the consistency of a brain tumor preoperatively, since the information is of much use in indicating the likely difficulty of the operation, which operative tools should be selected, the amount of bleeding to be expected from the tumor, and so on. The authors, therefore, tried to evaluate the consistency of brain tumors preoperatively. Twenty-seven cases in which the margin of the tumor was made clear with a homogeneous stain were studied concerning the relationship between the tumor consistency and the CT findings. The results are as follows: 1) A higher CT number on a plain CT indicated a harder consistency of the tumor. 2) A lesser contrast index (CT number on enhancement CT/CT number on plain CT) showed a harder consistency of the tumor.

  13. Study on the application of PET-CT in gynecology tumors

    International Nuclear Information System (INIS)

    Wen Lilian

    2012-01-01

    Gynecology tumors seriously threatened the health of female. With the development of imageology, PET, a functionality examination method, has been widely used in the early diagnosis and monitoring of curative effect in gynecology tumors. PET-CT has the good future in its development because it combined with the advantage of functional and structural imaging. The characters and application of PET-CT in gynecology tumors were reviewed in this paper. (author)

  14. CT and MRI evaluation of orbital tumors: our experience

    International Nuclear Information System (INIS)

    Cabrini, Marcelo; Docampo, Jorge; Martinez, Manuel; Bruno, Claudio; Morales, Carlos

    2007-01-01

    Purpose: To show our experience in the evaluation of orbital masses on computed tomography (CT) and magnetic resonance imaging (MRI). To describe their most important findings and epidemiological features found on literature review, related to their differential diagnosis. Materials and methods: During a 48-months period of time, 26 patients (13 male, 13 female; age range, 3 to 75 years) with orbital tumors were evaluated. Seventeen patients underwent MR scans, 8 underwent CT scans, and one underwent both imaging methods. It was employed 0,5 and 1 Tesla MR scanners, and axial-helical CT scanners. Results: Benign lesions were found on 7 patients (cavernous hemangioma [n=2], meningioma [n=1], epidermoid cyst [n=1], dermoid cyst [n=1], lipoma [n=1], orbital vein deformity [n=1]). It was found lesions with undetermined behavior (optical nerve glioma [n=2]), and malignant ones were found on 17 patients (metastatic lesions [n=5], non- Hodgkin's lymphoma [n=3], hemangiopericytoma [n=2], retinoblastoma [n=2], rhabdomyosarcoma [n=2], melanoma [n=1], and lacrimal adenocarcinoma [n=1]). Conclusion: In our experience, 65.4% was malignant tumors (orbital metastasis was the most common; 19.2%). More than one-quarter was benign tumor, where cavernous hemangioma was the most frequent. (author) [es

  15. Imaging manifestation of hepatocellular carcinoma with bile duct tumor thrombi

    International Nuclear Information System (INIS)

    Liu Qingyu; Chen Jianyu; Liang Biling; Hu Tao

    2008-01-01

    Objective: To analyze the imaging features of hepatocellular carcinoma(HCC) with bile duct tumor thrombi. Methods: Thirteen patients with bile duct tumor thrombi proved pathologically underwent imaging examination. MR and CT were performed in 3 cases, and 2 cases had CT only and 8 cases had MRI only. Ultrasonography(US) was performed in all 13 patients. The accuracy of bile duct tumor thrombi detection was compared between US, CT and MRI with Fisher test. Results: Liver tumors and bile duct tumor thrombi were demonstrated in all patients on CT or MRI. Presence of intraluminal soft tissue mass was found in four of five cases on CT, and mild enhancement of the intraluminal mass in the arterial phase was noted, dilated bile duct distal to tumor thrombi was detected in all five patients. Eleven Tumor thrombi showed slight low signal intensity on T 1 WI, slight high signal intensity on T 2 WI, and mild to moderate contrast enhancement on the contrast-enhanced MR images. The MRCP findings of tumor thrombi were as follows: interruption, stricture of the bile ducts or irregular filling defect in the bile ducts with dilated intrahepatic ducts, bile duet was abruptly interrupted or showed a 'rat-tail' stricture (n=5); the common bile duct was filled with tumor thrombi, intrahepatic bile duct dilatation and missing common bile duct was noted on MRCP (n=2). Bile duct tumor thrombi were correctly diagnosed in 7 cases on US, and 12 cases on CT or MRI. Six cases were misdiagnosed or miss-diagnosed on US, and 4 cases were misdiagnosed on CT or MRI. There was no significant difference between US and CT/MRI in diagnosis of bile duct tumor thrombi (P=0.270). Conclusion: CT or MR imaging is useful for the diagnosis of HCC with biliary tumor thrombi and for evaluating the extension of thrombi. (authors)

  16. Imaging of brain tumors

    International Nuclear Information System (INIS)

    Gaensler, E.H.L.

    1995-01-01

    The contents are diagnostic approaches, general features of tumors -hydrocephalus, edema, attenuation and/or intensity value, hemorrhage, fat, contrast enhancement, intra-axial supratentorial tumors - tumors of glial origin, oligodendrogliomas, ependymomas, subependymomas, subependymal giant cell astrocytomas, choroid plexus papilloma; midline tumors - colloid cysts, craniopharyngiomas; pineal region tumors and miscellaneous tumors i.e. primary intracerebral lymphoma, primitive neuroectodermal tumors, hemangioblastomas; extraaxial tumors - meningiomas; nerve sheath tumors -schwannomas, epidermoids, dermoids, lipomas, arachnoid cysts; metastatic tumors (8 refs.)

  17. Imaging of brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Gaensler, E H.L. [California Univ., San Francisco, CA (United States). Dept. of Radiology

    1996-12-31

    The contents are diagnostic approaches, general features of tumors -hydrocephalus, edema, attenuation and/or intensity value, hemorrhage, fat, contrast enhancement, intra-axial supratentorial tumors - tumors of glial origin, oligodendrogliomas, ependymomas, subependymomas, subependymal giant cell astrocytomas, choroid plexus papilloma; midline tumors - colloid cysts, craniopharyngiomas; pineal region tumors and miscellaneous tumors i.e. primary intracerebral lymphoma, primitive neuroectodermal tumors, hemangioblastomas; extraaxial tumors - meningiomas; nerve sheath tumors -schwannomas, epidermoids, dermoids, lipomas, arachnoid cysts; metastatic tumors (8 refs.).

  18. Utility of Electrocardiography (ECG)-Gated Computed Tomography (CT) for Preoperative Evaluations of Thymic Epithelial Tumors.

    Science.gov (United States)

    Ozawa, Yoshiyuki; Hara, Masaki; Nakagawa, Motoo; Shibamoto, Yuta

    2016-01-01

    Preoperative evaluation of invasion to the adjacent organs is important for the thymic epithelial tumors on CT. The purpose of our study was to evaluate the utility of electrocardiography (ECG)-gated CT for assessing thymic epithelial tumors with regard to the motion artifacts produced and the preoperative diagnostic accuracy of the technique. Forty thymic epithelial tumors (36 thymomas and 4 thymic carcinomas) were examined with ECG-gated contrast-enhanced CT using a dual source scanner. The scan delay after the contrast media injection was 30 s for the non-ECG-gated CT and 100 s for the ECG-gated CT. Two radiologists blindly evaluated both the non-ECG-gated and ECG-gated CT images for motion artifacts and determined whether the tumors had invaded adjacent structures (mediastinal fat, superior vena cava, brachiocephalic veins, aorta, pulmonary artery, pericardium, or lungs) on each image. Motion artifacts were evaluated using a 3-grade scale. Surgical and pathological findings were used as a reference standard for tumor invasion. Motion artifacts were significantly reduced for all structures by ECG gating ( p =0.0089 for the lungs and p ECG-gated CT and ECG-gated CT demonstrated 79% and 95% accuracy, respectively, during assessments of pericardial invasion ( p =0.03). ECG-gated CT reduced the severity of motion artifacts and might be useful for preoperative assessment whether thymic epithelial tumors have invaded adjacent structures.

  19. Definition of postlumpectomy tumor bed for radiotherapy boost field planning: CT versus surgical clips

    International Nuclear Information System (INIS)

    Goldberg, Hadassah; Prosnitz, Robert G.; Olson, John A.; Marks, Lawrence B.

    2005-01-01

    Purpose: To compare the location and extent of the tumor bed as defined by surgical clips and computed tomography (CT) scans, after lumpectomy, for electron boost planning as part of breast radiotherapy. Methods and Materials: Planning CT images of 31 operated breasts in 30 patients who underwent lumpectomy were reviewed. One or more clips were placed in the lumpectomy cavity. Serial CT images were used to measure the depth and transverse and longitudinal dimensions. The area and geometric center of the tumor bed were defined by the clips and CT. Results: The CT and clip measurements were identical for the maximal tumor depth in 27 of 30 patients. The CT bed extended beyond the clips by 0-7 mm medially in the transverse/longitudinal extent (multiclip patients). The median distance between the geometric centers in the coronal plane for the tumor bed center was larger for patients with single clips than for those with multiple clips (p 2 . The CT bed was more readily visible in patients with a shorter interval between surgery and radiotherapy. Conclusion: The maximal depth of the tumor bed was similar using the two methods. The extent and centers of the clip-and CT-determined beds differed significantly. This may indicate an underestimation of the tumor bed as defined by clips only and justifies integration of CT information in boost field planning

  20. PET CT imaging: the Philippine experience

    International Nuclear Information System (INIS)

    Santiago, Jonas Y.

    2011-01-01

    Currently, the most discussed fusion imaging is PET CT. Fusion technology has tremendous potential in diagnostic imaging to detect numerous conditions such as tumors, Alzheimer's disease, dementia and neural disorders. The fusion of PET with CT helps in the localization of molecular abnormalities, thereby increasing diagnostic accuracy and differentiating benign or artefact lesions from malignant diseases. It uses a radiotracer called fluro deoxyglucose that gives a clear distinction between pathological and physiological uptake. Interest in this technology is increasing and additional clinical validation are likely to induce more health care providers to invest in combined scanners. It is hope that in time, a better appreciation of its advantages over conventional and traditional imaging modalities will be realized. The first PET CT facility in the country was established at the St. Luke's Medical Center in Quezon City in 2008 and has since then provided a state-of-the art imaging modality to its patients here and those from other countries. The paper will present the experiences so far gained from its operation, including the measures and steps currently taken by the facility to ensure optimum workers and patient safety. Plans and programs to further enhance the awareness of the Filipino public on this advanced imaging modality for an improved health care delivery system may also be discussed briefly. (author)

  1. Imaging of pancreatic tumors with PET

    International Nuclear Information System (INIS)

    Zanzi, I.; Robeson, W.; Vinciquerra, V.; Chaly, T.; Kroop, S.; Dahl, R.; Schulman, P.; Goldman, S.; Margouleff, D.

    1990-01-01

    This paper identifies pancreatic tumors with positron emission tomography (PET) using F-18 2-fluorodeoxyglucose (FDG). PET studies were performed in 13 patients with pancreatic tumors (11 adenocarcinomas; two islet cell tumors) using FDG. Data were acquired for 1 hour and in 14 contiguous 7-mm sections after attenuation correction. Suspicious areas were evaluated using quantitative techniques. In seven of 11 patients with adenocarcinomas, focal increase in FDG uptake correlated with pancreatic tumor shown on CT scans or MR images. Of the remaining four, one had a previous Whipple procedure, another had completed chemotherapy, and in two the tumor was out of the limited region imaged; in these four patients, liver metastases were identified in three

  2. The role of CT in the diagnosis of tumors in sellar area

    International Nuclear Information System (INIS)

    Li Wenxin

    2005-01-01

    Objective: To evaluate computed tomography (CT) in patients with tumors in sellar area. Methods: CT images of 33 patients with sellar area tumor's proved by surgery and pathology were analyzed retrospectively. Results: Pituitary adenomas (n=20), craniopharyngiomas (n=8) and meningiomas (n=3) had characteristic findings and were given a high rate of correct diagnosis. While astrocytoma (n=1) and germinoma (n=1) were solid lesions in sellar area and lack of diagnostic signs and the astrocytoma was misdiagnosed as craniopharyngioma. Conclusion: CT, especially 2-demision reconstructed (coronal and sagittal) images can demonstrate inner structure, pattern of growth, extension of invasion of tumors as well as the relationship between tumor and the adjacent vessels. CT plays an important role in the diagnosis of tumors in seliar area. (authors)

  3. Characterization of tumor heterogeneity using dynamic contrast enhanced CT and FDG-PET in non-small cell lung cancer

    International Nuclear Information System (INIS)

    Elmpt, Wouter van; Das, Marco; Hüllner, Martin; Sharifi, Hoda; Zegers, Catharina M.L.; Reymen, Bart; Lambin, Philippe; Wildberger, Joachim E.; Troost, Esther G.C.; Veit-Haibach, Patrick; De Ruysscher, Dirk

    2013-01-01

    Purpose: Dynamic contrast-enhanced CT (DCE-CT) quantifies vasculature properties of tumors, whereas static FDG-PET/CT defines metabolic activity. Both imaging modalities are capable of showing intra-tumor heterogeneity. We investigated differences in vasculature properties within primary non-small cell lung cancer (NSCLC) tumors measured by DCE-CT and metabolic activity from FDG-PET/CT. Methods: Thirty three NSCLC patients were analyzed prior to treatment. FDG-PET/CT and DCE-CT were co-registered. The tumor was delineated and metabolic activity was segmented on the FDG-PET/CT in two regions: low (<50% maximum SUV) and high (⩾50% maximum SUV) metabolic uptake. Blood flow, blood volume and permeability were calculated using a maximum slope, deconvolution algorithm and a Patlak model. Correlations were assessed between perfusion parameters for the regions of interest. Results: DCE-CT provided additional information on vasculature and tumor heterogeneity that was not correlated to metabolic tumor activity. There was no significant difference between low and high metabolic active regions for any of the DCE-CT parameters. Furthermore, only moderate correlations between maximum SUV and DCE-CT parameters were observed. Conclusions: No direct correlation was observed between FDG-uptake and parameters extracted from DCE-CT. DCE-CT may provide complementary information to the characterization of primary NSCLC tumors over FDG-PET/CT imaging

  4. Nephrogenic rests mimicking Wilms' tumor on CT

    International Nuclear Information System (INIS)

    Subhas, Naveen; Siegelman, Stanley S.; Argani, Pedram; Gearhart, John P.

    2004-01-01

    Nephrogenic rests (NR) are persistent benign remnants of embryonic renal tissue. A small percentage of these may develop into Wilms' tumor (WT). Radiologic imaging is relied upon to differentiate between these entities, with the hallmark of malignant transformation being growth on serial imaging studies. There is, however, considerable overlap in their imaging characteristics. The authors present a case of two biopsy-proven NR in a 2-year-old girl with sporadic aniridia that were indistinguishable from WT on initial radiologic studies. One of the NR grew on serial imaging studies mimicking a WT, but after resection was confirmed to be a benign hyperplastic NR on pathologic examination. (orig.)

  5. Image mottle in abdominal CT.

    Science.gov (United States)

    Ende, J F; Huda, W; Ros, P R; Litwiller, A L

    1999-04-01

    To investigate image mottle in conventional CT images of the abdomen as a function of radiographic technique factors and patient size. Water-filled phantoms simulating the abdomens of adult (32 cm in diameter) and pediatric (16 cm in diameter) patients were used to investigate image mottle in CT as a function of x-ray tube potential and mAs. CT images from 39 consecutive patients with noncontrast liver scans and 49 patients with iodine contrast scans were analyzed retrospectively. Measurements were made of the mean liver parenchyma Hounsfield unit value and the corresponding image mottle. For a given water phantom and x-ray tube potential, image mottle was proportional to the mAs-0.5. Increasing the phantom diameter from 16 cm (pediatric) to 32 cm increased the mottle by a factor of 2.4, and increasing the x-ray tube potential from 80 kVp to 140 kVp reduced the mottle by a factor of 2.5. All patients were scanned at 120 kVp, with no correlation between patient size and the x-ray tube mAs. The mean mottle level was 7.8 +/- 2.2 and 10.0 +/- 2.5 for the noncontrast and contrast studies, respectively. An increase in patient diameter of 3 cm would require approximately 65% more mAs to maintain the same level of image mottle. The mottle in abdominal CT images may be controlled by adjusting radiographic technique factors, which should be adjusted to take into account the size of the patient undergoing the examination.

  6. Multi-slice spiral CT diagnosis of carotid body tumor

    International Nuclear Information System (INIS)

    Li Peiling; Leng Renli; Li Shu; Xie Xiuli; Xu Ke

    2006-01-01

    Objective: to explore the Multi-slice spiral CT (MSCT) findings of carotid body tumor (CBT). Methods: Twelve cases of CBT proved by surgery were collected in this study and all patients accepted contrast-enhanced MSCT examination. Two-dimensional and three-dimensional post-processing were performed at diagnostic workstation using Aquilion 1.42. The CT features of CBT were analyzed. Results Each of 12 patients had one lesion. All lesions demonstrated well-marginated masses of homogeneous soft- tissue density with CT value within 29-48 HU on pre-enhanced images. All lesions were markedly enhanced with CT value over 200 HU on arterial-phase images, and the density of lesions decreased rapidly on delay- phase images. Twelve lesions were all located at the level of carotid artery bifurcation, 3 of them enveloping common carotid artery and internal/external carotid artery, and other 9 of them riding right on the carotid bifurcation. Internal carotid artery usually were shifted toward posterior-lateral, and external carotid artery toward anterior or anterior-medial. Conclusion: Contrast-enhanced MSCT examination not only can make a qualitative diagnosis of CBT, but determine its accurate location. It plays an importantly instructional role in clinical diagnosis and treatment. (authors)

  7. Arterial displacement by the tumor demonstrated by magnetic resonance CT

    International Nuclear Information System (INIS)

    Tsuchiya, Kazuhiro; Yoshikawa, Kohki; Machida, Tohru; Iio, Masahiro.

    1985-01-01

    MR-CT permits visualization of blood vessels non-invasively. Major blood vessels in scan slices are demonstrated as structures with low or no signal intensity. In this report, two cases with brain tumor and spinal tumor are presented in which arterial displacement by the tumor was visualized by MR-CT. MR-CT is considered to be an effective method in detecting blood vessel abnormalities. (author)

  8. Optimal CT scanning parameters for commonly used tumor ablation applicators

    International Nuclear Information System (INIS)

    Eltorai, Adam E.M.; Baird, Grayson L.; Monu, Nicholas; Wolf, Farrah; Seidler, Michael; Collins, Scott; Kim, Jeomsoon; Dupuy, Damian E.

    2017-01-01

    Highlights: • This study aimed to determine optimal scanning parameters for commonly-used tumor ablation applicators. • The findings illustrate the overall interaction of the effects of kVp, ASiR, and reconstruction algorithm within and between probes, so that radiologists may easily reference optimal imaging performance. • Optimum combinations for each probe are provided. - Abstract: Purpose: CT-beam hardening artifact can make tumor margin visualization and its relationship to the ablation applicator tip challenging. To determine optimal scanning parameters for commonly-used applicators. Materials and methods: Applicators were placed in ex-vivo cow livers with implanted mock tumors, surrounded by bolus gel. Various CT scans were performed at 440 mA with 5 mm thickness changing kVp, scan time, ASiR, scan type, pitch, and reconstruction algorithm. Four radiologists blindly scored the images for image quality and artifact quantitatively. Results: A significant relationship between probe, kVp level, ASiR level, and reconstruction algorithm was observed concerning both image artifact and image quality (both p = <0.0001). Specifically, there are certain combinations of kVp, ASiR, and reconstruction algorithm that yield better images than other combinations. In particular, one probe performed equivalently or better than any competing probe considered here, regardless of kVp, ASiR, and reconstruction algorithm combination. Conclusion: The findings illustrate the overall interaction of the effects of kVp, ASiR, and reconstruction algorithm within and between probes, so that radiologists may easily reference optimal imaging performance for a certain combinations of kVp, ASiR, reconstruction algorithm and probes at their disposal. Optimum combinations for each probe are provided.

  9. Optimal CT scanning parameters for commonly used tumor ablation applicators

    Energy Technology Data Exchange (ETDEWEB)

    Eltorai, Adam E.M. [Warren Alpert Medical School of Brown University (United States); Baird, Grayson L. [Department of Diagnostic Imaging (United States); Warren Alpert Medical School of Brown University (United States); Lifespan Biostatistics Core (United States); Rhode Island Hospital (United States); Monu, Nicholas; Wolf, Farrah; Seidler, Michael [Department of Diagnostic Imaging (United States); Warren Alpert Medical School of Brown University (United States); Rhode Island Hospital (United States); Collins, Scott [Department of Diagnostic Imaging (United States); Rhode Island Hospital (United States); Kim, Jeomsoon [Department of Medical Physics (United States); Rhode Island Hospital (United States); Dupuy, Damian E., E-mail: ddupuy@comcast.net [Department of Diagnostic Imaging (United States); Warren Alpert Medical School of Brown University (United States); Rhode Island Hospital (United States)

    2017-04-15

    Highlights: • This study aimed to determine optimal scanning parameters for commonly-used tumor ablation applicators. • The findings illustrate the overall interaction of the effects of kVp, ASiR, and reconstruction algorithm within and between probes, so that radiologists may easily reference optimal imaging performance. • Optimum combinations for each probe are provided. - Abstract: Purpose: CT-beam hardening artifact can make tumor margin visualization and its relationship to the ablation applicator tip challenging. To determine optimal scanning parameters for commonly-used applicators. Materials and methods: Applicators were placed in ex-vivo cow livers with implanted mock tumors, surrounded by bolus gel. Various CT scans were performed at 440 mA with 5 mm thickness changing kVp, scan time, ASiR, scan type, pitch, and reconstruction algorithm. Four radiologists blindly scored the images for image quality and artifact quantitatively. Results: A significant relationship between probe, kVp level, ASiR level, and reconstruction algorithm was observed concerning both image artifact and image quality (both p = <0.0001). Specifically, there are certain combinations of kVp, ASiR, and reconstruction algorithm that yield better images than other combinations. In particular, one probe performed equivalently or better than any competing probe considered here, regardless of kVp, ASiR, and reconstruction algorithm combination. Conclusion: The findings illustrate the overall interaction of the effects of kVp, ASiR, and reconstruction algorithm within and between probes, so that radiologists may easily reference optimal imaging performance for a certain combinations of kVp, ASiR, reconstruction algorithm and probes at their disposal. Optimum combinations for each probe are provided.

  10. 68Ga DOTA-TATE PET/CT allows tumor localization in patients with tumor-induced osteomalacia but negative 111In-octreotide SPECT/CT.

    Science.gov (United States)

    Breer, Stefan; Brunkhorst, Thomas; Beil, F Timo; Peldschus, Kersten; Heiland, Max; Klutmann, Susanne; Barvencik, Florian; Zustin, Jozef; Gratz, Klaus-Friedrich; Amling, Michael

    2014-07-01

    Tumor-induced osteomalacia (TIO) is a paraneoplastic syndrome characterized by renal phosphate wasting, hypophosphatemia and low calcitriol levels as well as clinical symptoms like diffuse bone and muscle pain, fatigue fractures or increased fracture risk. Conventional imaging methods, however, often fail to detect the small tumors. Lately, tumor localization clearly improved by somatostatin-receptor (SSTR) imaging, such as octreotide scintigraphy or octreotide SPECT/CT. However, recent studies revealed that still a large number of tumors remained undetected by octreotide imaging. Hence, studies focused on different SSTR imaging methods such as 68Ga DOTA-NOC, 68Ga DOTA-TOC and 68Ga DOTA-TATE PET/CT with promising first results. Studies comparing different SSTR imaging methods for tumor localization in TIO are rare and thus little is known about diagnostic alternatives once a particular method failed to detect a tumor in patients with TIO. Here, we report the data of 5 consecutive patients suffering from TIO, who underwent both 111Indium-octreotide scintigraphy (111In-OCT) SPECT/CT as well as 68Ga DOTA-TATE PET/CT for tumor detection. While 111In-OCT SPECT/CT allowed tumor detection in only 1 of 5 patients, 68Ga DOTA-TATE PET/CT was able to localize the tumor in all patients. Afterwards, anatomical imaging of the region of interest was performed with CT and MRI. Thus, successful surgical resection of the tumor was achieved in all patients. Serum phosphate levels returned to normal and all patients reported relief of symptoms within weeks. Moreover, an iliac crest biopsy was obtained from every patient and revealed marked osteomalacia in all cases. Follow-up DXA revealed an increase in BMD of up to 34.5% 1-year postoperative, indicating remineralization. No recurrence was observed. In conclusion our data indicates that 68Ga DOTA-TATE PET/CT is an effective and promising diagnostic tool in the diagnosis of TIO, even in patients in whom 111In-OCT prior failed to detect

  11. The importance of PET/CT in the evaluation of patients with Ewing tumors

    Directory of Open Access Journals (Sweden)

    Júlio Brandão Guimarães

    2015-06-01

    Full Text Available Abstract The effective evaluation for the treatment of patients with Ewing tumors depends on the accuracy in the determination of the primary tumor extent and the presence of metastatic disease. Currently, no universally accepted staging system is available to assess Ewing tumors. The present study aimed at discussing the use of PET/CT as a tool for staging, restaging and assessment of therapeutic response in patients with Ewing tumors. In spite of some limitations of PET/CT as compared with anatomical imaging methods, its relevance in the assessment of these patients is related to the capacity of the method to provide further physiological information, which often generates important clinical implications. Currently, the assessment of patients with Ewing tumor should comprise a study with PET/CT combined with other anatomical imaging modalities, such as radiography, computed tomography and magnetic resonance imaging.

  12. Ball-in-ball ZrO2 nanostructure for simultaneous CT imaging and highly efficient synergic microwave ablation and tri-stimuli-responsive chemotherapy of tumors.

    Science.gov (United States)

    Long, Dan; Niu, Meng; Tan, Longfei; Fu, Changhui; Ren, Xiangling; Xu, Ke; Zhong, Hongshan; Wang, Jingzhuo; Li, Laifeng; Meng, Xianwei

    2017-06-29

    Combined thermo-chemotherapy displays outstanding synergically therapeutic efficiency when compared with standalone thermotherapy and chemotherapy. Herein, we developed a smart tri-stimuli-responsive drug delivery system involving X@BB-ZrO 2 NPs (X represents loaded IL, DOX, keratin and tetradecanol) based on novel ball-in-ball-structured ZrO 2 nanoparticles (BB-ZrO 2 NPs). The microwave energy conversion efficiency of BB-ZrO 2 NPs was 41.2% higher than that of traditional single-layer NPs due to the cooperative action of self-reflection and spatial confinement effect of the special two-layer hollow nanostructure. The tri-stimuli-responsive controlled release strategy indicate that integrated pH, redox and microwaves in single NPs based on keratin and tetradecanol could effectively enhance the specific controlled release of DOX. The release of DOX was only 8.1% in PBS with pH = 7.2 and GSH = 20 μM. However, the release could reach about 50% at the tumor site (pH = 5.5, GSH = 13 mM) under microwave ablation. The as-made X@BB-ZrO 2 NPs exhibited perfect synergic therapy effect of chemotherapy and microwave ablation both in subcutaneous tumors (H22 tumor-bearing mice) and deep tumors (liver transplantation VX2 tumor-bearing rabbit model). There was no recurrence and death in the X@BB-ZrO 2 + MW group during the therapy of subcutaneous tumors even on the 42 nd day. The growth rates in the deep tumor of the control, MW and X@BB-ZrO 2 + MW groups were 290.1%, 14.1% and -42% 6 days after ablation, respectively. Dual-source CT was used to monitor the metabolism behavior of the as-made BB-ZrO 2 NPs and traditional CT was utilized to monitor the tumor growth in rabbits. Frozen section examination and ICP results indicated the precise control of drug delivery and enhanced cytotoxicity by the tri-stimuli-responsive controlled release strategy. The ball-in-ball ZrO 2 NPs with high microwave energy conversion efficiency were first developed for synergic microwave ablation and

  13. Reproducibility of 'Intelligent' Contouring of Gross Tumor Volume in Non-Small-Cell Lung Cancer on PET/CT Images Using a Standardized Visual Method

    International Nuclear Information System (INIS)

    Bayne, Michael; Hicks, Rodney J.; Everitt, Sarah; Fimmell, Natalie

    2010-01-01

    Purpose: Positron emission tomography/computed tomography (PET/CT) is increasingly used for delineating gross tumor volume (GTV) in non-small-cell lung cancer (NSCLC). The methodology for contouring tumor margins remains controversial. We developed a rigorous visual protocol for contouring GTV that uses all available clinical information and studied its reproducibility in patients from a prospective PET/CT planning trial. Methods and Materials: Planning PET/CT scans from 6 consecutive patients were selected. Six 'observers' (two radiation oncologists, two nuclear medicine physicians, and two radiologists) contoured GTVs for each patient using a predefined protocol and subsequently recontoured 2 patients. For the estimated GTVs and axial distances, least-squares means for each observer and for each case were calculated and compared, using the F test and pairwise t-tests. In five cases, tumor margins were also autocontoured using standardized uptake value (SUV) cutoffs of 2.5 and 3.5 and 40% SUV max . Results: The magnitude of variation between observers was small relative to the mean (coefficient of variation [CV] = 3%), and the total variation (intraclass correlation coefficient [ICC] = 3%). For estimation of superior/inferior (SI), left/right (LR), and anterior/posterior (AP) borders of the GTV, differences between observers were also small (AP, CV = 2%, ICC = 0.4%; LR, CV = 6%, ICC = 2%; SI, CV 4%, ICC = 2%). GTVs autocontoured generated using SUV 2.5, 3.5, and 40% SUV max differed widely in each case. An SUV contour of 2.5 was most closely correlated with the mean GTV defined by the human observers. Conclusions: Observer variation contributed little to total variation in the GTV and axial distances. A visual contouring protocol gave reproducible results for contouring GTV in NSCLC.

  14. CT-guided radiofrequency tumor ablation in children

    International Nuclear Information System (INIS)

    Botsa, Evanthia; Poulou, Loukia S.; Koundouraki, Antonia; Thanos, Loukas; Koutsogiannis, Ioannis; Ziakas, Panayiotis D.; Alexopoulou, Efthimia

    2014-01-01

    Image-guided radiofrequency ablation is a well-accepted technique of interventional oncology in adults. To evaluate the efficacy and safety of CT-guided radiofrequency ablation as a minimally invasive treatment for metastatic neoplasms in children. A total of 15 radiofrequency ablation sessions were performed in 12 children and young adults (median age 9.5; range 5-18 years) with metastatic malignancies. Seven children and young adults had secondary hepatic lesions, three had pulmonary and two had bone lesions. Radiofrequency ablation was performed under conscious sedation. The median lesion size was 1.7 cm (range 1.3-2.8 cm). The median time for ablation was 8 min (range 7-10 min). Radiofrequency procedures were technically successful in all tumors. Postablation imaging immediately after, and 1 month and 3 months after radiofrequency ablation showed total necrosis in all patients. At 6-month follow-up, three patients (all with lesion size >2 cm) had local recurrence and underwent a second radiofrequency ablation session. At 2-year follow-up no patient had recurrence of the treated tumor. Post-ablation syndrome occurred in four children. No major complication occurred. CT-guided radiofrequency tumor ablation was safe and efficient for palliative treatment in our cohort of patients. (orig.)

  15. CT-guided radiofrequency tumor ablation in children

    Energy Technology Data Exchange (ETDEWEB)

    Botsa, Evanthia [National and Kapodistrian University of Athens, First Pediatric Clinic, Agia Sofia Children' s Hospital, Athens (Greece); Poulou, Loukia S.; Koundouraki, Antonia; Thanos, Loukas [Sotiria General Hospital for Chest Diseases, Department of Medical Imaging and Interventional Radiology, Athens (Greece); Koutsogiannis, Ioannis [General Military Hospital NIMTS, Department of Medical Imaging, Athens (Greece); Ziakas, Panayiotis D. [Warren Alpert Medical School of Brown University Rhode Island Hospital, Division of Infectious Diseases, Providence, RI (United States); Alexopoulou, Efthimia [Attikon University Hospital, Second Department of Radiology, Athens University School of Medicine, Athens (Greece)

    2014-11-15

    Image-guided radiofrequency ablation is a well-accepted technique of interventional oncology in adults. To evaluate the efficacy and safety of CT-guided radiofrequency ablation as a minimally invasive treatment for metastatic neoplasms in children. A total of 15 radiofrequency ablation sessions were performed in 12 children and young adults (median age 9.5; range 5-18 years) with metastatic malignancies. Seven children and young adults had secondary hepatic lesions, three had pulmonary and two had bone lesions. Radiofrequency ablation was performed under conscious sedation. The median lesion size was 1.7 cm (range 1.3-2.8 cm). The median time for ablation was 8 min (range 7-10 min). Radiofrequency procedures were technically successful in all tumors. Postablation imaging immediately after, and 1 month and 3 months after radiofrequency ablation showed total necrosis in all patients. At 6-month follow-up, three patients (all with lesion size >2 cm) had local recurrence and underwent a second radiofrequency ablation session. At 2-year follow-up no patient had recurrence of the treated tumor. Post-ablation syndrome occurred in four children. No major complication occurred. CT-guided radiofrequency tumor ablation was safe and efficient for palliative treatment in our cohort of patients. (orig.)

  16. Measurement of lung tumor motion using respiration-correlated CT

    International Nuclear Information System (INIS)

    Mageras, Gig S.; Pevsner, Alex; Yorke, Ellen D.; Rosenzweig, Kenneth E.; Ford, Eric C.; Hertanto, Agung; Larson, Steven M.; Lovelock, D. Michael; Erdi, Yusuf E.; Nehmeh, Sadek A.; Humm, John L.; Ling, C. Clifton

    2004-01-01

    Purpose: We investigate the characteristics of lung tumor motion measured with respiration-correlated computed tomography (RCCT) and examine the method's applicability to radiotherapy planning and treatment. Methods and materials: Six patients treated for non-small-cell lung carcinoma received a helical single-slice computed tomography (CT) scan with a slow couch movement (1 mm/s), while simultaneously respiration is recorded with an external position-sensitive monitor. Another 6 patients receive a 4-slice CT scan in a cine mode, in which sequential images are acquired for a complete respiratory cycle at each couch position while respiration is recorded. The images are retrospectively resorted into different respiration phases as measured with the external monitor (4-slice data) or patient surface displacement observed in the images (single-slice data). The gross tumor volume (GTV) in lung is delineated at one phase and serves as a visual guide for delineation at other phases. Interfractional GTV variation is estimated by scaling diaphragm position variations measured in gated radiographs at treatment with the ratio of GTV:diaphragm displacement observed in the RCCT data. Results: Seven out of 12 patients show GTV displacement with respiration of more than 1 cm, primarily in the superior-inferior (SI) direction; 2 patients show anterior-posterior displacement of more than 1 cm. In all cases, extremes in GTV position in the SI direction are consistent with externally measured extremes in respiration. Three patients show evidence of hysteresis in GTV motion, in which the tumor trajectory is displaced 0.2 to 0.5 cm anteriorly during expiration relative to inspiration. Significant (>1 cm) expansion of the GTV in the SI direction with respiration is observed in 1 patient. Estimated intrafractional GTV motion for gated treatment at end expiration is 0.6 cm or less in all cases; however; interfraction variation estimates (systematic plus random) are more than 1 cm in 3

  17. Magnetic resonance imaging of nasopharyngeal malignant tumors

    International Nuclear Information System (INIS)

    Sakakihara, Junji; Kanoh, Naoyuki; Hayakawa, Katsumi.

    1988-01-01

    Magnetic Resonance Imaging (MRI) was used in the examination of three patients with nasopharyngeal malignant tumor and cranial nerve symptoms. Coronal and saggital sections were very useful for determining skull base invasion. Its high contrast resolution enabled us to visualize several cranial nerves directly. Differentiation between tumor and effusion in the paranasal sinuses was easy especially in T2 weighted images. Bone destruction could also be detected as bone marrow replacement by tumor or as interruption of the black line of compact bone. Local relationships of tumor and large blood vessels were visualized by MRI without invasive contrast enhancing methods. Despite such advantages, in one patient whose symptoms were highly suggestive of cranial invasion, no cranial invasion was detected by CT or MRI. (author)

  18. Imaging of childhood inflammatory myofibroblastic tumor

    Energy Technology Data Exchange (ETDEWEB)

    Oguz, Berna; Ozcan, Hatice Nursun; Omay, Burak; Ozgen, Burce; Haliloglu, Mithat [Division of Pediatric Radiology, Hacettepe University Faculty of Medicine, Department of Radiology, Altindag / Sihhiye, Ankara (Turkey)

    2015-10-15

    Inflammatory myofibroblastic tumor is a rare benign neoplasm and most commonly involves the lung but occurs in extrapulmonary locations. To present imaging findings in inflammatory myofibroblastic tumors in children based on a single-centre experience. We retrospectively reviewed CT and MRI findings of children diagnosed with inflammatory myofibroblastic tumor in a single institution. We identified 15 children (range: 1-17 years) with inflammatory myofibroblastic tumor. The tumor was localized to the lung (n = 5), mediastinum (n = 3), trachea (n = 1), bronchus (n = 1), abdomen (n = 2) and orbit (n = 3). All the extraorbital tumors were solid masses with homogeneous or heterogeneous enhancement. Four lung tumors and one posterior mediastinal tumor contained calcification. Local recurrence following surgical removal occurred in two children with invasion of the esophagus and of the left atrium in one. Localized masses were seen in all children with orbital tumour. Two of these had episcleritis and perineuritis; one had episcleritis, tendonitis, perineuritis, myositis and dacryoadenitis. The locations and imaging features of inflammatory myofibroblastic tumors are variable. (orig.)

  19. Malignant gastroduodenal stromal tumor imaging diagnosis

    International Nuclear Information System (INIS)

    Guo Qiang; Wen Feng; Zhao Zhenguo

    2010-01-01

    Objective: To assess the imaging features of malignant gastroduodenal stromal tumor (mGDST)as an aid to its diagnosis. Methods: The unenhanced and multi-phasic contrast-enhanced CT scans of 24 patients with pathologically proven mGDST and air-contrast upper gastrointestinal studies(15 patients) were reviewed by two radiologists. The tumor location, size, contour, margin, growth type, contrast enhancement pattern and presence of ulcer were recorded. Results: The mGDST was located in the gastric fundus (15), gastric body(3), pylorus(2) and duodenum(4). The pathological types were submucosal(9), intramuscular(9) and subserosal(6). CT findings of mGDST included lobular shape(17), tumor size>5cm(14), central necrosis(15), large and deep ulcer(6), heterogeneous contrast enhancement(1), metastasis(1). The diagnostic accuracy of air-contrast upper gastrointestinal studies and CT for location of mGDST was 93.3% and 100% respectively, for malignant features was both 75.0%. Conclusion: Most mGDST have some characteristic appearances including large tumor size greater than 5 cm, lobular shape, central necrosis, large and deep ulcer, heterogeneous contrast enhancement and metastasis. Lymph node enlargement was uncommon. The diagnostic accuracy can be improved by CT scan combined with upper gastrointestinal barium examination. (authors)

  20. MR imaging assisted radiation therapy planning of brain tumors

    International Nuclear Information System (INIS)

    Just, M.; Roesler, H.P.; Higer, H.P.; Kutzner, J.; Thelen, M.

    1990-01-01

    This paper reports on the improvement of the accuracy of treatment portals in radiation therapy of brain tumors with use of MR imaging. After proper processing, the parasagittal MR image showing the largest tumor size and the midline sagittal image were superimposed. With common anatomic landmarks of midline tomogram and lateral simulation radiograph, commensurate reference grids were laid over both images in identical positions. Tumor coordinates were then transferred from the synthesized MR image to the lateral radiograph. Rectangular fields or individual shielding blocks encompassing the tumor could be drawn directly. This new method was used in 17 patients, and results were compared with CT-assisted results

  1. Importance of PET/CT for imaging of colorectal cancer

    International Nuclear Information System (INIS)

    Meinel, F.G.; Schramm, N.; Graser, A.; Reiser, M.F.; Rist, C.; Haug, A.R.

    2012-01-01

    Fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) has emerged as a very useful imaging modality in the management of colorectal carcinoma. Data from the literature regarding the role of PET/CT in the initial diagnosis, staging, radiotherapy planning, response monitoring and surveillance of colorectal carcinoma is presented. Future directions and economic aspects are discussed. Computed tomography (CT), magnetic resonance imaging (MRI) and FDG-PET for colorectal cancer and endorectal ultrasound for rectal cancer. Combined FDG-PET/CT. While other imaging modalities allow superior visualization of the extent and invasion depth of the primary tumor, PET/CT is most sensitive for the detection of distant metastases of colorectal cancer. We recommend a targeted use of PET/CT in cases of unclear M staging, prior to metastasectomy and in suspected cases of residual or recurrent colorectal carcinoma with equivocal conventional imaging. The role of PET/CT in radiotherapy planning and response monitoring needs to be determined. Currently there is no evidence to support the routine use of PET/CT for colorectal screening, staging or surveillance. To optimally exploit the synergy between morphologic and functional information, FDG-PET should generally be performed as an integrated FDG-PET/CT with a contrast-enhanced CT component in colorectal carcinoma. (orig.) [de

  2. Functional Imaging: CT and MRI

    OpenAIRE

    van Beek, Edwin JR; Hoffman, Eric A

    2008-01-01

    Numerous imaging techniques permit evaluation of regional pulmonary function. Contrast-enhanced CT methods now allow assessment of vasculature and lung perfusion. Techniques using spirometric controlled MDCT allow for quantification of presence and distribution of parenchymal and airway pathology, Xenon gas can be employed to assess regional ventilation of the lungs and rapid bolus injections of iodinated contrast agent can provide quantitative measure of regional parenchymal perfusion. Advan...

  3. The findings and the role of axial CT imaging and 3D imaging of gastric lesion by spiral CT

    International Nuclear Information System (INIS)

    Lee, Dong Ho; Ko, Young Tae

    1996-01-01

    The purpose of this study is to assess the efficacy of axial CT imaging and 3D imaging by spiral CT in the detection and evaluation of gastric lesion. Seventy-seven patients with pathologically-proven gastric lesions underwent axial CT and 3D imaging by spiral CT. There were 49 cases of advanced gastric carcinoma(AGC), 21 of early gastric carcinoma (EGC), three of benign ulcers, three of leiomyomas, and one case of lymphoma. Spiral CT was performed with 3-mm collimation, 4.5mm/sec table feed, and 1-1.5-mm reconstruction interval after the ingestion of gas. 3D imaging was obtained using the SSD technique, and on analysis a grade was given(excellent, good, poor). Axial CT scan was performed with 5-mm collimation, 7mm/sec table feed, and 5-mm reconstruction interval after the ingestion of water. Among 49 cases of AGC, excellent 3D images were obtained in seven patients (14.3%), good 3D images in 30(61.2%), and poor 3D images in 12(24.5%). Among the 12 patients with poor images, the cancers were located at the pyloric antrum in eight cases, were AGC Borrmann type 4 in three cases, and EGC-mimicking lesion in one case. Using axial CT scan alone, Borrmann's classification based tumor morphology were accurately identified in 67.3% of cases, but using 3D imaging, the corresponding figure was 85.7%. In 33 cases receiving surgery, good correlation between axial CT scan and pathology occurred in 72.7% of T class, and 69.7% of N class. Among 21 cases of EGC, excellent 3D images were obtained in three patients (14.3%), good 3D images in 14 (66.7%), and poor 3D images in two (9.5%). The other two cases of EGC were not detected. By axial CT scan, no tumor was detected in four cases, and there were two doubtful cases. 3D images of three benign ulcers were excellent in one case and good in two. 3D images of three leiomyomas and one lymphoma were excellent. Combined axial CT imaging and 3D imaging by spiral CT has the potential to accurately diagnose gastric lesions other than AGC

  4. (CT, MRI, USG) radiological diagnostics of neuroendocrine tumors

    International Nuclear Information System (INIS)

    Cwikla, J.; Furmanek, M.; Walecki, J.; Sankowski, A.; Pawlowska-Detko, A.

    2007-01-01

    Neuroendocrine tumors (NET) consists of a heterogeneneous group of neoplasma, that are able to express cell membrane neuroamine uptake mechanisms and/or specific receptors, which can be used in the localization and treatment of these tumours. Conventionally NETs may present with a wide variety of functional or nonfuctional endocrinesyndromes and may be familial and have other associated tumors, also they have different histology and prognosis. They originate from endocrine glands such as the pituitary, the parathyroids, and the neuroendocrine) adrenal, as well as endocrine islets within glandular tissue (thyroid or pancreatic) and cells dispersed between exocrine cells, such as endocrine cells of the digestive system (gastroenteropancreatic GEP-NET0 and respiratory tracts. GEp-NET are the the most common including more 70% of all NETs. Imaging modalities and assessment of specific tumors markers offers high sensitivity in establishing the diagnosis and can also have pronostic significance. One of most important single imaging techniques in terms of initial identification and staging o GET-NET are CT and somatostatin receptor scintigraphy (SRS). Other investigation like magnetic resonance imaging (MRI), endoscopic (EUS) are used for the precise localization of GEP-NET. Another techniques including functional approach 123 I MIBG (meta-iodobenzylguanidine scintigraphy) and FDG PET.Important using of imaging approach is monitoring of response on treatment. (author)

  5. Role of respiratory-gated PET/CT for pancreatic tumors: A preliminary result

    International Nuclear Information System (INIS)

    Kasuya, Takeo; Tateishi, Ukihide; Suzuki, Kazufumi; Daisaki, Hiromitsu; Nishiyama, Yuji; Hata, Masaharu; Inoue, Tomio

    2013-01-01

    Purpose: The aim of this study is to ascertain role of respiratory-gated PET/CT for accurate diagnosis of pancreatic tumors. Materials and methods: Prior to clinical study, the phantom study was performed to evaluate the impact of respiratory motion on lesion quantification. Twenty-two patients (mean age 65 years) with pancreatic tumors were enrolled. Pathological diagnoses by surgical specimens consisted of pancreatic cancer (n = 15) and benign intraductal papillary mucinous neoplasm (IPMN, n = 7). Whole-body scan of non-respiratory-gated PET/CT was performed at first, and subsequent respiratory-gated PET/CT for one bed position was performed. All PET/CT studies were performed prior to surgery. The SUV max obtained by non-respiratory-gated PET/CT and respiratory-gated PET/CT, and percent difference in SUVmax (%SUVmax) were compared. Results: The profile curve of 5 respiratory bin image was most similar to that of static image. The third bin of 5 respiratory bin image showed highest FWHM (24.0 mm) and FWTM (32.7 mm). The mean SUVmax of pancreatic cancer was similar to that of benign IPMN on non-respiratory-gated PET/CT (p = 0.05), whereas significant difference was found between two groups on respiratory-gated PET/CT (p = 0.016). The mean %SUV of pancreatic cancer was greater than that of benign IPMN (p < 0.0001). Identification of the primary tumor in pancreatic head (n = 13, 59%) was improved by using respiratory-gated PET/CT because of minimal affection of physiological accumulation in duodenum. Conclusion: Respiratory-gated PET/CT is a feasible technique for evaluation of pancreatic tumors and allows more accurate identification of pancreatic tumors compared with non-respiratory-gated PET/CT

  6. Molecular Imaging with Small Animal PET/CT

    DEFF Research Database (Denmark)

    Binderup, T.; El-Ali, H.H.; Skovgaard, D.

    2011-01-01

    is also described. In addition, the non-invasive nature of molecular imaging and the targets of these promising new tracers are attractive for other research areas as well, although these fields are much less explored. We present an example of an interesting research field with the application of small......Small animal positron emission tomography (PET) and computer tomography (CT) is an emerging field in pre-clinical imaging. High quality, state-of-the-art instruments are required for full optimization of the translational value of the small animal studies with PET and CT. However...... in this field of small animal molecular imaging with special emphasis on the targets for tissue characterization in tumor biology such as hypoxia, proliferation and cancer specific over-expression of receptors. The added value of applying CT imaging for anatomical localization and tumor volume measurements...

  7. Metastatic liver tumor from cystic ovarian carcinomas. CT and MRI appearance

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Yi; Yamashita, Yasuyuki; Ogata, Ichiro; Namimoto, Tomohiro; Abe, Yasuko; Urata, Joji; Takahashi, Mutsumasa [Kumamoto Univ. (Japan). School of Medicine

    1999-08-01

    The initial and follow-up CT and MRI images of ten patients with hepatic metastases from ovarian tumors were retrospectively analyzed to establish their features and sequential changes in appearance. Ten patients with hepatic metastasis from ovarian tumors received initial and follow-up CT and MRI examinations. Six patients were followed up every two to three weeks before surgical tumor resection. Both CT and MR images were analyzed by two radiologists. A total of fourteen lesions were detected by CT and MRI in 10 patients. All 14 lesions were demonstrated as areas of marked hyperintensity on T2-weighted MRI. Eleven cyst-like tumors were demonstrated as round or oval low density lesions on CT and as areas of hypointensity on T1-weighted imaging. Three lesions were shown as solid masses with slightly low attenuation at the initial CT examination and slightly low or iso-intensity areas on T1-weighted imaging, and these lesions showed early peripheral globular enhancement and delayed enhancement on contrast-enhanced CT and MR imaging. Cystic formation was observed two to three weeks later after initial study in all the 3 solid lesions. Rapid subcapsular effusion, which showed obvious enhancement on delayed Gd-DTPA enhanced MR imaging, was observed in two patients. The hepatic metastatic tumor from cystic ovarian carcinoma may manifest as a well-defined cystic lesion or as a solid mass, and the solid mass shows delayed enhancement on contrast-enhanced CT and MR imaging. Furthermore, rapid cystic formation and rapid subcapsular extension is frequently seen. (author)

  8. Evaluation of magnetic resonance imaging in thoracic inlet tumors

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Eiro (Kobe Univ. (Japan). School of Medicine)

    1993-06-01

    To evaluate the detectability of tumor invasion to the thoracic inlet, MRI was performed in 57 patients with thoracic inlet tumor, and the diagnostic accuracy of MRI was compared with that of CT concerning the utility for thoracic inlet lesions. And we assessed abnormal findings in comparison with surgical or autopsy findings. In the local extent of the tumor, the accuracy for tumor invasion to the vessels such as subclavian artery and vein was 94.9% for MRI, and 83.5% for CT, and to the brachial plexus was 95.0% for MRI, and 60.0% for CT. MRI was superior to CT, but MRI was equivalent to CT with regard to invasion to the base of the neck, lateral chest wall, ribs, and vertebral bodies. However on MRI, it is easier to understand the longitudinal tumor extent than on CT. CT has superior spatial resolusion but CT has also disadvantages, such as streak artifact caused by shoulder joints, resulting in image degradation. In contrast, MRI has inherent advantages, and multiple images which facilitate the relationship between tumor and normal structures. Coronal and sagittal MR images facilitated three-dimensional observation of tumor of invasion in the thoracic inlet. Furthermore to improve image quality of MRI for the thoracic inlet, we newly devised a high molecular polyester shell for fixing a surface coil. On the high resolution MR (HR-MR) imaging using our shell, normal lymph nodes, muscles, blood vessels and the branches of the branchial plexus were clearly visualized in detail. Our shell was simple to process and facilitated immobilization of a surface coil. HR-MR technique produces images of high resolution after simple preparation. In conclusion, MRI was very useful for detecting lesions of the thoracic inlet and in deciding surgical indication and the planning for radiotherapy. (author).

  9. Peculiarities in the CT findings of germ cell tumors in various tumor localizations

    International Nuclear Information System (INIS)

    Tazoe, Makoto; Miyagami, Mitsusuke; Tsubokawa, Takashi

    1991-01-01

    The CT findings of 17 germ cell tumors were studied in relation to the locations of the tumor, the pathological diagnoses, and the tumor markers (AFP and HCG). Generally, the CT findings of germ cell tumors depended on the pathological diagnoses more strongly than on the location of the tumors. On plain CT of 7 germ cell tumors in the pineal region, all of them demonstrated heterogeneous findings. Hydrocephalus was seen in 6 cases (86%) and calcification in 6 cases (86%) of the germ cell tumors in the pineal region. Calcification and hydrocephalus that appeared more often than in other regions were characteristic of germ cell tumors of the pineal region. The germ cell tumors in the basal ganglia had a slightly homogenous high density, with small cysts and calcification in most of them on plain CT. On enhanced CT, the tumors were moderately enhanced in all cases located in the basal ganglia. Four cases of germ cell tumors located in the basal ganglia revealed the dilatation of lateral ventricle due to hemispheric atrophy in the tumor side. The germ cell tumors showing an increase in the tumor markers such as AFP and HCG, which were usually malignant germ cell tumors, were strongly enhanced on enhanced CT. (author)

  10. Primary staging of laryngeal and hypopharyngeal cancer: CT, MR imaging and dual-energy CT

    International Nuclear Information System (INIS)

    Kuno, Hirofumi; Onaya, Hiroaki; Fujii, Satoshi; Ojiri, Hiroya; Otani, Katharina; Satake, Mitsuo

    2014-01-01

    Laryngeal and hypopharyngeal cancer, in particular T4a disease associated with cartilage invasion and extralaryngeal spread, needs to be evaluated accurately because treatment can impact heavily on a patient's quality of life. Reliable imaging tools are therefore indispensible. CT offers high spatial and temporal resolution and remains the preferred imaging modality. Although cartilage invasion can be diagnosed with acceptable accuracy by applying defined criteria for combinations of erosion, lysis and transmural extralaryngeal spread, iodine-enhanced tumors and non-ossified cartilage are sometimes difficult to distinguish. MR offers high contrast resolution for images without motion artifacts, although inflammatory changes in cartilage sometimes resemble cartilage invasion. With dual-energy CT, combined iodine overlay images and weighted average images can be used for evaluation of cartilage invasion, since iodine enhancement is evident in tumor tissue but not in cartilage. Extralaryngeal spread can be evaluated from CT, MR or dual-energy CT images and the routes of tumor spread into the extralaryngeal soft tissue must be considered; (1) via the thyrohyoid membrane along the superior laryngeal neurovascular bundle, (2) via the inferior pharyngeal constrictor muscle, and (3) via the cricothyroid membrane. Radiologists need to understand the advantages and limitations of each imaging modality for staging of laryngeal and hypopharyngeal cancer

  11. CT and MR imaging of gynecological emergency disease

    International Nuclear Information System (INIS)

    Fujii, Shinya; Kinoshita, Toshibumi; Tahara, Takatoshi; Matsusue, Eiji; Ogawa, Toshihide

    2004-01-01

    We describe the CT and MRI findings of gynecologic emergency diseases: pelvic inflammatory disease, ectopic pregnancy, ovarian hemorrhage, ovarian torsion, rupture of ovarian tumor, eclampsia, and HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome. Diagnostic keys to these diseases are presented in this review. CT and MRI play a complementary role to sonography in accurately diagnosing these diseases. In situations that require an exact, immediate diagnosis, radiologists should be familiar with the key imaging findings. (author)

  12. Soft tissue tumors - imaging methods

    International Nuclear Information System (INIS)

    Arlart, I.P.

    1985-01-01

    Soft Tissue Tumors - Imaging Methods: Imaging methods play an important diagnostic role in soft tissue tumors concerning a preoperative evaluation of localization, size, topographic relationship, dignity, and metastatic disease. The present paper gives an overview about diagnostic methods available today such as ultrasound, thermography, roentgenographic plain films and xeroradiography, radionuclide methods, computed tomography, lymphography, angiography, and magnetic resonance imaging. Besides sonography particularly computed tomography has the most important diagnostic value in soft tissue tumors. The application of a recently developed method, the magnetic resonance imaging, cannot yet be assessed in its significance. (orig.) [de

  13. Magnetic resonance imaging in brain-stem tumors

    International Nuclear Information System (INIS)

    Nomura, Mikio; Saito, Hisazumi; Akino, Minoru; Abe, Hiroshi.

    1988-01-01

    Four patients with brain-stem tumors underwent magnetic resonance imaging (MRI) before and after radiotherapy. The brain-stem tumors were seen as a low signal intensity on T1-weighted images and as a high signal intensity on T2-weighted images. A tumor and its anatomic involvement were more clearly visualized on MRI than on cuncurrently performed CT. Changes in tumor before and after radiotherapy could be determined by measuring the diameter of tumor on sagittal and coronal images. This allowed quantitative evaluation of the reduction of tumor in association with improvement of symptoms. The mean T1 value in the central part of tumors was shortened in all patients after radiotherapy. The results indicate that MRI may assist in determining the effect of radiotherapy for brain-stem tumors. (Namekawa, K)

  14. Bone tumors of the pediatric foot: imaging appearances

    Energy Technology Data Exchange (ETDEWEB)

    Caro-Dominguez, Pablo; Navarro, Oscar M. [University of Toronto, Department of Medical Imaging, Toronto, ON (Canada); The Hospital for Sick Children, Department of Diagnostic Imaging, Toronto, ON (Canada)

    2017-05-15

    Tumors of the foot are rare in children. This review illustrates radiographic, CT and MR imaging findings of foot bone tumors in children based on all cases presented in a tertiary pediatric hospital during the 15-year period of 1999-2014. This search revealed 155 tumors of the foot, 72 of the bones and 83 of the soft tissues. Osteochondroma, bone cyst and fibrous dysplasia were the most frequent benign bone lesions. Ewing sarcoma was the most common malignant osseous tumor. Some tumors showed higher prevalence in certain age ranges and others showed predilection for specific bones. Radiographs are useful for diagnosis in the majority of cases but CT and MR imaging provide additional valuable information in select cases for diagnosis and determining extent of the lesions. Radiologists should be aware of some typical imaging findings in bone tumors of the foot in order to establish diagnosis and facilitate patient management. (orig.)

  15. Diagnosis of pelvic wall tumor on multislice CT

    International Nuclear Information System (INIS)

    Zhang Keyun; Deng Lequn; Lei Hongwei

    2011-01-01

    Objective: To evaluate the value of multi-slice CT (MSCT) in diagnosing pelvic wall tumors. Methods: MSCT of 21 cases of pelvic wall tumors including metastasis (10), neurogenic tumor (5), chondrosarcoma (2), chordoma (1), aneurysmal bone cyst (1), giant cell tumor (1), and osteochondroma (1) was retrospectively analyzed. Results: CT appearances of pelvic wall tumors include bony destruction and soft tissue masses. Common features were bone destruction in metastasis, expansion of the neuroforamen in neurogenic tumor, pleomorphic calcification in chondrosarcoma, lower sacral vertebral location of chordoma, iliac crest bone destruction in giant cell tumor, cauliflower-like nodules in osteochondroma. Conclusion: MSCT with three-dimensional volume rendering demonstrates well the tumor shape, size, extent, internal structure and relationship with the surrounding organs to aid diagnosis of pelvic wall tumors. (authors)

  16. [Method of radiotherapy planning for head and neck tumors using simulated CT images and radiographic data, developed at the Gustave Roussy Institute].

    Science.gov (United States)

    Bridier, A; Diaz, J C; Kafrouni, H; Leclerc, A; Barrois, M M; Rivet, P; Wibault, P; Bourhis, J; Eschwège, F

    2001-06-01

    The paper deals with the recent improvements introduced in the most usual method applied in the Institut Gustave Roussy radiotherapy department for obtaining the anatomical data of patients treated for head and neck tumors. For each of these patients, five to seven transverses slices and a lateral radiographic film are taken from a Mecaserto simulator-CT. The anatomical representation of the patient sagittal plane is carried out from the digitalisation of the radiographic film on a Vidar Vxr-12 Plus film scanner and integrated into the Dosigray dose calculation programme in order to be used as a support for the laying out of the dose distribution in reference to the treatment. The sagittal anatomical representation obtained from the radiographic film digitalisation is compared with the one resulting from the interpolation between a limited number of irregularly-spaced transverse slices taken on the simulator-CT. The method using the simulator-scanner transverse slices and the radiographic film digitalisation represents an interesting alternative for obtaining an anatomy simulation representative of the patient in hospitals where a scanner is not available full-time for the needs of the radiotherapy process.

  17. Comparative evaluation of the porta hepatis/hepatoduodenal ligament with CT and MR imaging

    International Nuclear Information System (INIS)

    Silverman, P.M.; Feuerstein, I.M.; Zeman, R.K.; Jaffe, M.H.; Garra, B.S.

    1988-01-01

    CT and MR imaging were compared in a retrospective evaluation of 16 patients with abnormalities, predominantly neoplasms, of the porta hepatis/hepatoduodenal ligament. Masses on CT were of decreased density compared with that of liver and were seen in contrast to surrounding periportal fat. On MR images, T1-weighted images demonstrated findings similar to those of CT. T2-weighted images clearly depicted intrahepatic lesions but less distinctly depicted lesions surrounded by fat. Short inversion recovery (STIR) images better demonstrated tumor relative to fat. CT was better than all MR imaging sequences in one of 16 cases, whereas at least one MR imaging sequence was better than CT in six of 16. In nine cases, CT was equivalent to the best MR imaging sequence. In five of six cases where MR imaging was better than CT, STIR sequences were most favorable. In conclusion, MR imaging provided a valuable technique for assessing abnormalities of the porta hepatis/hepatoduodenal ligament

  18. Gastric stromal tumor: two-phase dynamic CT findings with water as oral contrast agents

    International Nuclear Information System (INIS)

    Lee, Se Hyo; Cho, June Sik; Shin, Kyung Sook; Jeong, Ki Ho; Park, Jin Yong; Yu, Ho Jun; Kim, Young Min; Jeon, Kwang Jin

    2000-01-01

    To evaluate two-phase dynamic CT with water as oral contrast agents in the CT diagnosis of gastric stromal tumors. We retrospectively reviewed the CT findings in 21 patients with pathologically proven gastric stromal tumors. Six were found to be benign, twelve were malignant, and there were three cases of STUMP (stromal tumor uncertain malignant potential). Two-phase dynamic CT scans with water as oral contrast agents were obtained 60-70 secs (portal phase) and 3 mins (equilibrium phase) after the start of IV contrast administration. We determined the size, growth pattern, and enhancement pattern of the tumors and overlying mucosa, the presence or absence of ulceration and necrosis, tumor extent, and lymph nod and distant metastasis. The CT and pathologic findings were correlated. All six benign tumors and three STUMP were less than 5.5 cm in size, and during the portal phase showed round endogastric masses with highly enhanced, intact overlying mucosa. Twelve malignant tumors were 4.5-15.5 cm in size (mean, 11.5 cm); an endogastric mass was seen in three cases, an exogastric mass in one, and a mixed pattern in eight. On portal phase images the tumors were not significantly enhanced, but highly enhanced feeding vessels were noted in five larger tumors (greater than 10 cm). All 12 malignant tumors showed ulceration and necrosis, and interruption of overlying mucosa was clearly seen during the portal phase. We were readily able to evaluate tumor extent during this phase, and in ten malignant tumors there was no invasion of adjacent organs. Seven malignant tumors showed air density within their necrotic portion (p less than 0.05). On equilibrium phase images, all malignant tumors showed heterogeneous enhancement due to necrosis, and poorly enhanced overlying mucosa. Dynamic CT during the portal phase with water as oral contrast agents was useful for depicting the submucosal origin of gastric stromal tumors and for evaluating the extent of malignant stromal tumors. Our

  19. Thin section helical CT findings of klastskin tumor and benign stricture: cholangiographic correlation

    International Nuclear Information System (INIS)

    Choi, Guk Myeong; Han, Joon Koo; Kim, Tae Kyoung; Choi, Byung Ihn; Kim, Sun Whe; Cho, Yun Ku; Han, Man Chung; Yeon, Kyung Mo

    1997-01-01

    The purpose of this study was 1) to describe the thin section helical CT findings of hilar cholangiocarcinoma and of benign strcture, and to discuss the differential points between the two disease entities and 2) using cholangiographic correlation, to evaluate the diagnostic accuracy of helical CT in determining the extent of hilar cholangiocarcinoma. Twenty-seven patients with hilar cholangiocarcinoma and eight with benign biliary dilatation were studied. All except four with hilar cholangiocarcinoma, who underwentCT using a conventional scanner, were studied with two-phase helical CT. In all patients, cholangiographs were obtained by digital fluoroscopy after the injection of contrast materials into PTBD catheters. The level of obstruction was classified according to Bismuth, and 35 CT scans were studied blindly and retrospectively by two radiologists. The findings were analyzed for the presence of tumor, and then divided into two groups(cholangiocarcinomas and benign strictures), and the positive predictive value was calculated. The CT images of klatskin tumor were analyzed with special emphasis on the level and shape of the hilar obstruction. The level of biliary obstruction and extent of the tumor were carefully correlated with the results of cholangiography. Thin-section spiral CT correctly identified all tumor mass as a focal wall thickening obliterating the lumen. On arterial/portal phase CT scanning, 81% of infilterative tumors showed high attenuation. In all patients, differentiation between benign stricture and klaskin tumor was possible;correct identification of the level of obstruction and extent of tumor, according to Bismuth's classification, was possible in 63% of cases. For correct diagnosis of hilar cholangiocarcinoma and differentiation of benign stricture, helical CT was highly accurate and effective. Because of limital Z-axis resolution, however, the exact intraductal extent of the tumor was less accorately diagnosed.=20

  20. Magnetic resonance imaging in the head and neck tumor diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, Yasuyuki; Igarashi, Masahito; Miyata, Mamoru; Sonoda, Tetsushi; Miyoshi, Shunji; Hiraide, Fumihisa; Morita, Mamoru; Tanaka, Osamu

    1987-06-01

    MRI (magnetic resonance imaging) is a new diagnostic technique that is being applied to study disease processes that involve the upper aero-digestive tract and cranial nerves of interest to otolaryngologist. Seventy four patients with head and neck tumor were enrolled to study the diagnostic efficacy of MRI in comparison with X-ray computed tomography (X-ray CT). Five cases of head and neck tumors were presented. Characteristic findings of MRI were discussed. T2 weighted images are very useful in the diagnosis of head and neck tumors. Tumors in the areas surrounded by bone tissue were clearly imaged without such artifacts as recognized in X-ray CT. Information from mutiplane imaging, especially from coronal and sagittal sections, made it easier to determine the type and extent of the lesion. High signal linear parts which are in the periphery of the tumor offer important information that no adhesion is present.

  1. Lack of Correlation Between External Fiducial Positions and Internal Tumor Positions During Breath-Hold CT

    International Nuclear Information System (INIS)

    Hunjan, Sandeep; Starkschall, George; Prado, Karl; Dong Lei; Balter, Peter

    2010-01-01

    Purpose: For thoracic tumors, if four-dimensional computed tomography (4DCT) is unavailable, the internal margin can be estimated by use of breath-hold (BH) CT scans acquired at end inspiration (EI) and end expiration (EE). By use of external surrogates for tumor position, BH accuracy is estimated by minimizing the difference between respiratory extrema BH and mean equivalent-phase free breathing (FB) positions. We tested the assumption that an external surrogate for BH accuracy correlates with internal tumor positional accuracy during BH CT. Methods and Materials: In 16 lung cancer patients, 4DCT images, as well as BH CT images at EI and EE, were acquired. Absolute differences between BH and mean equivalent-phase (FB) positions were calculated for both external fiducials and gross tumor volume (GTV) centroids as metrics of external and internal BH accuracy, respectively, and the results were correlated. Results: At EI, the absolute difference between mean FB and BH fiducial displacement correlated poorly with the absolute difference between FB and BH GTV centroid positions on CT images (R 2 = 0.11). Similarly, at EE, the absolute difference between mean FB and BH fiducial displacements correlated poorly with the absolute difference between FB and BH GTV centroid positions on CT images (R 2 = 0.18). Conclusions: External surrogates for tumor position are not an accurate metric of BH accuracy for lung cancer patients. This implies that care should be taken when using such an approach because an incorrect internal margin could be generated.

  2. Imaging modalities of abdominal tumors in children

    International Nuclear Information System (INIS)

    Reither, M.

    1993-01-01

    Further technological progress in cross-sectional imaging modalities, accumuting experience with increasingly refined hardware and software and accumulating specific contrast media allow new algorithms for the assessment of abdominal tumors in children. However, ultrasound remains the diagnostic method of choice: Conventional roentgenology with or without contrast media is decreasing, but often reveals further differential diagnostic details. MRI is becoming more prominent and is often performed immediately after ultrasound. The inauguration of gradient echo sequences and consequent shorter examination times combined with the elimination of pulsation and motion artefacts extends the diagnostic spectrum of the upper and middle abdomen. The application of oral or rectal contrast agents for imaging of the GI tract ameliorates the differentiation of pathologic processes. Recently volumetric CT/ultrafast CT has been gaining in importance for abdominal examinations in the pediatric age group. CT especially is helpful if there are bony structures in the region being examined. CT, however, involves ionizing radiation and timely administration of oral and intravenous contrast material. Moreover, as pediatric radiologists, we must strongly withstand tendencies to perform CT more often because it is less expensive, rather than avoiding ionizing radiation by using MRI. (orig.) [de

  3. Imaging Tumor Necrosis with Ferumoxytol.

    Directory of Open Access Journals (Sweden)

    Maryam Aghighi

    Full Text Available Ultra-small superparamagnetic iron oxide nanoparticles (USPIO are promising contrast agents for magnetic resonance imaging (MRI. USPIO mediated proton relaxation rate enhancement is strongly dependent on compartmentalization of the agent and can vary depending on their intracellular or extracellular location in the tumor microenvironment. We compared the T1- and T2-enhancement pattern of intracellular and extracellular USPIO in mouse models of cancer and pilot data from patients. A better understanding of these MR signal effects will enable non-invasive characterizations of the composition of the tumor microenvironment.Six 4T1 and six MMTV-PyMT mammary tumors were grown in mice and imaged with ferumoxytol-enhanced MRI. R1 relaxation rates were calculated for different tumor types and different tumor areas and compared with histology. The transendothelial leakage rate of ferumoxytol was obtained by our measured relaxivity of ferumoxytol and compared between different tumor types, using a t-test. Additionally, 3 patients with malignant sarcomas were imaged with ferumoxytol-enhanced MRI. T1- and T2-enhancement patterns were compared with histopathology in a descriptive manner as a proof of concept for clinical translation of our observations.4T1 tumors showed central areas of high signal on T1 and low signal on T2 weighted MR images, which corresponded to extracellular nanoparticles in a necrotic core on histopathology. MMTV-PyMT tumors showed little change on T1 but decreased signal on T2 weighted images, which correlated to compartmentalized nanoparticles in tumor associated macrophages. Only 4T1 tumors demonstrated significantly increased R1 relaxation rates of the tumor core compared to the tumor periphery (p<0.001. Transendothelial USPIO leakage was significantly higher for 4T1 tumors (3.4±0.9x10-3 mL/min/100cm3 compared to MMTV-PyMT tumors (1.0±0.9x10-3 mL/min/100 cm3. Likewise, ferumoxytol imaging in patients showed similar findings with

  4. Small Submucosal Tumors of the Stomach: Differentiation of Gastric Schwannoma from Gastrointestinal Stromal Tumor with CT

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jin Wook; Choi, Dong Gil; Kim, Kyoung Mee; Sohn, Tae Sung; Lee, Jun Haeng; Kim, Hee Jung; Lee, Soon Jin [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2012-07-15

    To identify the CT features that help differentiate gastric schwannomas (GS) from small (5 cm or smaller) gastrointestinal stromal tumors (GIST) and to assess the growth rates of both tumors. We included 16 small GSs and 56 GISTs located in the stomach. We evaluated the CT features including size, contour, surface pattern, margins, growth pattern, pattern and degree of contrast enhancement, and the presence of intralesional low attenuation area, hemorrhage, calcification, surface dimpling, fistula, perilesional lymph nodes (LNs), invasion to other organs, metastasis, ascites, and peritoneal seeding. We also estimated the tumor volume doubling time. Compared with GISTs, GSs more frequently demonstrated a homogeneous enhancement pattern, exophytic or mixed growth pattern, and the presence of perilesional LNs (each p < 0.05). The intralesional low attenuation area was more common in GISTs than GSs (p < 0.05). Multivariate analyses indicated that a homogeneous enhancement pattern, exophytic or mixed growth pattern, and the presence of perilesional LNs were statistically significant (p < 0.05). Tumor volume doubling times for GSs (mean, 1685.4 days) were significantly longer than that of GISTs (mean, 377.6 days) (p = 0.004). Although small GSs and GISTs show similar imaging findings, GSs more frequently show an exophytic or mixed growth pattern, homogeneous enhancement pattern, perilesional LNs and grow slower than GISTs.

  5. Small Submucosal Tumors of the Stomach: Differentiation of Gastric Schwannoma from Gastrointestinal Stromal Tumor with CT

    International Nuclear Information System (INIS)

    Choi, Jin Wook; Choi, Dong Gil; Kim, Kyoung Mee; Sohn, Tae Sung; Lee, Jun Haeng; Kim, Hee Jung; Lee, Soon Jin

    2012-01-01

    To identify the CT features that help differentiate gastric schwannomas (GS) from small (5 cm or smaller) gastrointestinal stromal tumors (GIST) and to assess the growth rates of both tumors. We included 16 small GSs and 56 GISTs located in the stomach. We evaluated the CT features including size, contour, surface pattern, margins, growth pattern, pattern and degree of contrast enhancement, and the presence of intralesional low attenuation area, hemorrhage, calcification, surface dimpling, fistula, perilesional lymph nodes (LNs), invasion to other organs, metastasis, ascites, and peritoneal seeding. We also estimated the tumor volume doubling time. Compared with GISTs, GSs more frequently demonstrated a homogeneous enhancement pattern, exophytic or mixed growth pattern, and the presence of perilesional LNs (each p < 0.05). The intralesional low attenuation area was more common in GISTs than GSs (p < 0.05). Multivariate analyses indicated that a homogeneous enhancement pattern, exophytic or mixed growth pattern, and the presence of perilesional LNs were statistically significant (p < 0.05). Tumor volume doubling times for GSs (mean, 1685.4 days) were significantly longer than that of GISTs (mean, 377.6 days) (p = 0.004). Although small GSs and GISTs show similar imaging findings, GSs more frequently show an exophytic or mixed growth pattern, homogeneous enhancement pattern, perilesional LNs and grow slower than GISTs.

  6. CT and MR imaging of high cervical intradural lipomas

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Joo Hyeong; Choi, Woo Suk; Lee, Sun Wha; Lim, Jae Hoon; Leem, Woon; Kim, Gook Ki; Rhee, Bong Arm [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1988-04-15

    Intradural spinal lipoma occurs in less than 1% of all spinal cord tumors. It has been described at every level of the spinal canal, although its most common location is the cervicothoracic and thoracic region. However, lipoma located in the high cervical region is very unusual. We described two cases, a teenager and an adult, with progressive neurologic deficit from such a lipomatous tumor, which were evaluated by CT scanning and MR imaging.

  7. Adaptive radiotherapy based on contrast enhanced cone beam CT imaging

    International Nuclear Information System (INIS)

    Soevik, Aaste; Skogmo, Hege K.; Roedal, Jan; Lervaag, Christoffer; Eilertsen, Karsten; Malinen, Eirik

    2010-01-01

    Cone beam CT (CBCT) imaging has become an integral part of radiation therapy, with images typically used for offline or online patient setup corrections based on bony anatomy co-registration. Ideally, the co-registration should be based on tumor localization. However, soft tissue contrast in CBCT images may be limited. In the present work, contrast enhanced CBCT (CECBCT) images were used for tumor visualization and treatment adaptation. Material and methods. A spontaneous canine maxillary tumor was subjected to repeated cone beam CT imaging during fractionated radiotherapy (10 fractions in total). At five of the treatment fractions, CECBCT images, employing an iodinated contrast agent, were acquired, as well as pre-contrast CBCT images. The tumor was clearly visible in post-contrast minus pre-contrast subtraction images, and these contrast images were used to delineate gross tumor volumes. IMRT dose plans were subsequently generated. Four different strategies were explored: 1) fully adapted planning based on each CECBCT image series, 2) planning based on images acquired at the first treatment fraction and patient repositioning following bony anatomy co-registration, 3) as for 2), but with patient repositioning based on co-registering contrast images, and 4) a strategy with no patient repositioning or treatment adaptation. The equivalent uniform dose (EUD) and tumor control probability (TCP) calculations to estimate treatment outcome for each strategy. Results. Similar translation vectors were found when bony anatomy and contrast enhancement co-registration were compared. Strategy 1 gave EUDs closest to the prescription dose and the highest TCP. Strategies 2 and 3 gave EUDs and TCPs close to that of strategy 1, with strategy 3 being slightly better than strategy 2. Even greater benefits from strategies 1 and 3 are expected with increasing tumor movement or deformation during treatment. The non-adaptive strategy 4 was clearly inferior to all three adaptive strategies

  8. Detection and preoperative staging of carcinoma of the cervix: Comparison between MR imaging and CT

    International Nuclear Information System (INIS)

    Mayr, B.; Schmidt, H.; Baieri, P.; Scheidel, P.; Meier, W.; Schramm, T.

    1986-01-01

    Twenty-four patients with carcinoma of the cervix were examined preoperatively by MR imaging and CT. In all patients histopathologic confirmation was available for specimens obtained either by radical hysterectomy or at staging laparotomy. MR imaging was equivalent to contrast CT in the detection and evaluation of tumor extension in the cervix. Tumor extension to the parametria and pelvic wall was difficult to evaluate on both modalities, as neither had a higher accuracy than pelvic examination conducted under anesthesia. Nodal staging was nearly equivalent on MR imaging and CT. In the detection and staging of carcinoma of the cervix, MR imaged proved to be as good as CT with contrast agent enhancement

  9. Brain Tumor Image Segmentation in MRI Image

    Science.gov (United States)

    Peni Agustin Tjahyaningtijas, Hapsari

    2018-04-01

    Brain tumor segmentation plays an important role in medical image processing. Treatment of patients with brain tumors is highly dependent on early detection of these tumors. Early detection of brain tumors will improve the patient’s life chances. Diagnosis of brain tumors by experts usually use a manual segmentation that is difficult and time consuming because of the necessary automatic segmentation. Nowadays automatic segmentation is very populer and can be a solution to the problem of tumor brain segmentation with better performance. The purpose of this paper is to provide a review of MRI-based brain tumor segmentation methods. There are number of existing review papers, focusing on traditional methods for MRI-based brain tumor image segmentation. this paper, we focus on the recent trend of automatic segmentation in this field. First, an introduction to brain tumors and methods for brain tumor segmentation is given. Then, the state-of-the-art algorithms with a focus on recent trend of full automatic segmentaion are discussed. Finally, an assessment of the current state is presented and future developments to standardize MRI-based brain tumor segmentation methods into daily clinical routine are addressed.

  10. CT and MR findings of primitive neuroectodermal tumor

    International Nuclear Information System (INIS)

    Kook, Shin Ho; Kim, In One; Chang, Kee Hyun; Han, Moon Hee; Cho, Byung Kyu

    1991-01-01

    Cerebral primitive neuroectodermal tumor (PNET), consisting of undifferentiated primitive cells, is a neoplasm of children and young adults that occurs predominantly in the supratentorial compartment. In this report, we retrospectively reviewed and analyzed 18 CT and 6 MR findings in 18 patients with pathologically-proven PNET to discover the characteristic findings, if may. The most characteristic feature of the PNETs was a well-defined multilobular oval or round large mass with components of peripheral cystic change or calcification in the cerebral hemisphere, especially in the parietal lobe. Usually there was only minimal surrounding edema. The CT density of the tumor was iso - or slightly high density with homogeneous contrast enhancement in the solid portion and low density in the cystic area. MR findings demonstrated iso - signal intensity on both T1 - weighted (T1WI) and T2-weighted (T2WI) images and dense enhancement in the solid element. The cystic portion revealed low intensity on T1WI and high intensity on T2WI

  11. Comparison of proton therapy treatment planning for head tumors with a pencil beam algorithm on dual and single energy CT images

    Energy Technology Data Exchange (ETDEWEB)

    Hudobivnik, Nace; Dedes, George; Parodi, Katia; Landry, Guillaume, E-mail: g.landry@lmu.de [Department of Medical Physics, Ludwig-Maximilians-University, Munich 85748 (Germany); Schwarz, Florian; Johnson, Thorsten; Sommer, Wieland H. [Institute for Clinical Radiology, Ludwig Maximilians University Hospital Munich, 81377 Munich (Germany); Agolli, Linda [Department of Radiation Oncology, Ludwig-Maximilians-University, Munich 81377, Germany and Radiation Oncology, Sant’ Andrea Hospital, Sapienza University, Rome 00189 (Italy); Tessonnier, Thomas [Department of Medical Physics, Ludwig-Maximilians-University, Munich 85748, Germany and Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg (Germany); Verhaegen, Frank [Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht 6229 ET, the Netherlands and Medical Physics Unit, Department of Oncology, McGill University, Montreal, Quebec H3A 0G4 (Canada); Thieke, Christian; Belka, Claus [Department of Radiation Oncology, Ludwig-Maximilians-University, Munich 81377 (Germany)

    2016-01-15

    Purpose: Dual energy CT (DECT) has recently been proposed as an improvement over single energy CT (SECT) for stopping power ratio (SPR) estimation for proton therapy treatment planning (TP), thereby potentially reducing range uncertainties. Published literature investigated phantoms. This study aims at performing proton therapy TP on SECT and DECT head images of the same patients and at evaluating whether the reported improved DECT SPR accuracy translates into clinically relevant range shifts in clinical head treatment scenarios. Methods: Two phantoms were scanned at a last generation dual source DECT scanner at 90 and 150 kVp with Sn filtration. The first phantom (Gammex phantom) was used to calibrate the scanner in terms of SPR while the second served as evaluation (CIRS phantom). DECT images of five head trauma patients were used as surrogate cancer patient images for TP of proton therapy. Pencil beam algorithm based TP was performed on SECT and DECT images and the dose distributions corresponding to the optimized proton plans were calculated using a Monte Carlo (MC) simulation platform using the same patient geometry for both plans obtained from conversion of the 150 kVp images. Range shifts between the MC dose distributions from SECT and DECT plans were assessed using 2D range maps. Results: SPR root mean square errors (RMSEs) for the inserts of the Gammex phantom were 1.9%, 1.8%, and 1.2% for SECT phantom calibration (SECT{sub phantom}), SECT stoichiometric calibration (SECT{sub stoichiometric}), and DECT calibration, respectively. For the CIRS phantom, these were 3.6%, 1.6%, and 1.0%. When investigating patient anatomy, group median range differences of up to −1.4% were observed for head cases when comparing SECT{sub stoichiometric} with DECT. For this calibration the 25th and 75th percentiles varied from −2% to 0% across the five patients. The group median was found to be limited to 0.5% when using SECT{sub phantom} and the 25th and 75th percentiles

  12. CT assessment of the correlation between clinical examination and bone involvement in oral malignant tumors

    International Nuclear Information System (INIS)

    Albuquerque, Marco Antonio Portela; Oliveira, Ilka Regina Souza; Cavalcanti, Marcelo Gusmao Paraiso; Kuruoshi, Marcia Etsuko

    2009-01-01

    Oral cancers have a tendency to invade the surrounding bone structures, and this has a direct influence on the treatment management and on outcomes. The objective of this study was to correlate the clinical parameters (location, clinical presentation and TNM staging) of oral malignant tumors that can be associated with a potential of bone invasion and determine the accuracy of clinical examination to predict bone involvement, using computed tomography (CT). Twenty five patients, with oral malignant tumors were submitted to clinical and CT examinations. CT was considered the standard parameter to evaluate the presence of bone involvement. Clinical assessment of location, presentation form and TNM staging of the tumors were then compared to the CT findings in predicting bone involvement. Bone involvement was observed in 68% of the cases. It was predicted that tumors located in the retromolar trigone and hard palate, with a clinical aspect of infiltrative ulcer or nodule and classified in stage IV had a high potential to cause bone involvement. The clinical examination assessment of these tumors showed to be a valuable tool to predict bone invasion, with high sensitivity (82%) and specificity (87.5%), based on the results found in the CT images. No statistical significance was found between the CT and clinical examinations regarding bone involvement. The identification of some clinical parameters such as location, clinical presentation, and TNM stage, associated with a detailed clinical examination, was considered a valuable tool for the assessment of bone destruction by oral malignant tumors. (author)

  13. 18F-Fluoride PET/CT tumor burden quantification predicts survival in breast cancer.

    Science.gov (United States)

    Brito, Ana E; Santos, Allan; Sasse, André Deeke; Cabello, Cesar; Oliveira, Paulo; Mosci, Camila; Souza, Tiago; Amorim, Barbara; Lima, Mariana; Ramos, Celso D; Etchebehere, Elba

    2017-05-30

    In bone-metastatic breast cancer patients, there are no current imaging biomarkers to identify which patients have worst prognosis. The purpose of our study was to investigate if skeletal tumor burden determined by 18F-Fluoride PET/CT correlates with clinical outcomes and may help define prognosis throughout the course of the disease. Bone metastases were present in 49 patients. On multivariable analysis, skeletal tumor burden was significantly and independently associated with overall survival (p breast cancer patients (40 for primary staging and the remainder for restaging after therapy). Clinical parameters, primary tumor characteristics and skeletal tumor burden were correlated to overall survival, progression free-survival and time to bone event. The median follow-up time was 19.5 months. 18F-Fluoride PET/CT skeletal tumor burden is a strong independent prognostic imaging biomarker in breast cancer patients.

  14. Multimodal imaging in neurofibromatosis type 1-associated nerve sheath tumors

    International Nuclear Information System (INIS)

    Salamon, J.; Adam, G.; Mautner, V.F.; Derlin, T.

    2015-01-01

    Neurofibromatosis type 1 (NF1) is a neurogenetic disorder. Individuals with NF1 may develop a variety of benign and malignant tumors of which peripheral nerve sheath tumors represent the most frequent entity. Plexiform neurofibromas may demonstrate a locally destructive growth pattern, may cause severe symptoms and may undergo malignant transformation into malignant peripheral nerve sheath tumors (MPNSTs). Whole-body magnetic resonance imaging (MRI) represents the reference standard for detection of soft tissue tumors in NF1. It allows for identification of individuals with plexiform neurofibromas, for assessment of local tumor extent, and for evaluation of whole-body tumor burden on T2-weighted imaging. Multiparametric MRI may provide a comprehensive characterization of different tissue properties of peripheral nerve sheath tumors, and may identify parameters associated with malignant transformation. Due to the absence of any radiation exposure, whole-body MRI may be used for serial follow-up of individuals with plexiform neurofibromas. 18 F-fluorodeoxyglucose positron-emission-tomography (FDG PET/CT) allows a highly sensitive and specific detection of MPNST, and should be used in case of potential malignant transformation of a peripheral nerve sheath tumor. PET/CT provides a sensitive whole-body tumor staging. The use of contrast-enhanced CT for diagnosis of peripheral nerve sheath tumors is limited to special indications. To obtain the most precise readings, optimized examination protocols and dedicated radiologists and nuclear medicine physicians familiar with the complex and variable morphologies of peripheral nerve sheath tumors are required.

  15. A modified VMAT adaptive radiotherapy for nasopharyngeal cancer patients based on CT-CT image fusion

    International Nuclear Information System (INIS)

    Jin, Xiance; Han, Ce; Zhou, Yongqiang; Yi, Jinling; Yan, Huawei; Xie, Congying

    2013-01-01

    To investigate the feasibility and benefits of a modified adaptive radiotherapy (ART) by replanning in the initial CT (iCT) with new contours from a repeat CT (rCT) based on CT-CT image fusion for nasopharyngeal cancer (NPC) patients underwent volumetric modulated arc radiotherapy (VMAT). Nine NPC patients underwent VMAT treatment with a rCT at 23rd fraction were enrolled in this study. Dosimetric differences for replanning VMAT plans in the iCT and in the rCT were compared. Volumetric and dosimetric changes of gross tumor volume (GTV) and organs at risk (OARs) of this modified ART were also investigated. No dosimetric differences between replanning in the iCT and in the rCT were observed. The average volume of GTV decreased from 78.83 ± 38.42 cm 3 in the iCT to 71.44 ± 37.46 cm 3 in the rCT, but with no significant difference (p = 0.42).The average volume of the left and right parotid decreased from 19.91 ± 4.89 cm 3 and 21.58 ± 6.16 cm 3 in the iCT to 11.80 ± 2.79 cm 3 and 13.29 ± 4.17 cm 3 in the rCT (both p < 0.01), respectively. The volume of other OARs did not shrink very much. No significant differences on PTV GTV and PTV CTV coverage were observed for replanning with this modified ART. Compared to the initial plans, the average mean dose of the left and right parotid after re-optimization were decreased by 62.5 cGy (p = 0.05) and 67.3 cGy (p = 0.02), respectively, and the V5 (the volume receiving 5 Gy) of the left and right parotids were decreased by 7.8% (p = 0.01) and 11.2% (p = 0.001), respectively. There was no significant difference on the dose delivered to other OARs. Patients with NPC undergoing VMAT have significant anatomic and dosimetric changes to parotids. Repeat CT as an anatomic changes reference and re-optimization in the iCT based on CT-CT image fusion was accurate enough to identify the volume changes and to ensure safe dose to parotids

  16. Correlating tumor metabolic progression index measured by serial FDG PET-CT, apparent diffusion coefficient measured by magnetic resonance imaging (MRI) and blood genomics to patient’s outcome in advanced colorectal cancer: the CORIOLAN study

    International Nuclear Information System (INIS)

    Deleporte, Amelie; Charette, Nicolas; Machiels, Godelieve; Piccart, Martine; Flamen, Patrick; Hendlisz, Alain; Paesmans, Marianne; Garcia, Camilo; Vandeputte, Caroline; Lemort, Marc; Engelholm, Jean-Luc; Hoerner, Frederic; Aftimos, Philippe; Awada, Ahmad

    2014-01-01

    Metastatic colorectal cancer (mCRC) may present various behaviours that define different courses of tumor evolution. There is presently no available tool designed to assess tumor aggressiveness, despite the fact that this is considered to have a major impact on patient outcome. CORIOLAN is a single-arm prospective interventional non-therapeutic study aiming mainly to assess the natural tumor metabolic progression index (TMPI) measured by serial FDG PET-CT without any intercurrent antitumor therapy as a prognostic factor for overall survival (OS) in patients with mCRC. Secondary objectives of the study aim to test the TMPI as a prognostic marker for progression-free survival (PFS), to assess the prognostic value of baseline tumor FDG uptake on PFS and OS, to compare TMPI to classical clinico-biological assessment of prognosis, and to test the prognostic value on OS and PFS of MRI-based apparent diffusion coefficient (ADC) and variation of vADC using voxel-based diffusion maps. Additionally, this study intends to identify genomic and epigenetic factors that correlate with progression of tumors and the OS of patients with mCRC. Consequently, this analysis will provide information about the signaling pathways that determine the natural and therapy-free course of the disease. Finally, it would be of great interest to investigate whether in a population of patients with mCRC, for which at present no known effective therapy is available, tumor aggressiveness is related to elevated levels of circulating tumor cells (CTCs) and to patient outcome. Tumor aggressiveness is one of the major determinants of patient outcome in advanced disease. Despite its importance, supported by findings reported in the literature of extreme outcomes for patients with mCRC treated with chemotherapy, no objective tool allows clinicians to base treatment decisions on this factor. The CORIOLAN study will characterize TMPI using FDG-PET-based metabolic imaging of patients with chemorefractory m

  17. Analysis of the manifestation and feature of adrenal tumor on CT in 30 cases

    International Nuclear Information System (INIS)

    Xi Riquan; Xie Daohai; Guo Liang; Hu Chunhong; Fu Yingdi

    2001-01-01

    Objective: To analyze the manifestation and the feature of adrenal tumor with CT. Methods: The findings of various adrenal tumors with CT in 30 cases were analyzed retrospectively, the key to the diagnosis and differential diagnosis was suggested. Results: Usually, fibroxanthoma is inhomogeneous in density and moderate in size and was enhanced slightly after contrast medium administration. Pheochromocytoma is always larger and inhomogeneous in density and was enhanced markedly. The CT unit of myelo-lipoma simulated those of fluid or fat. Adrenal cyst has a low CT value and it showed cystic wall calcification. Aldosteronism adenoma was low in density and small in size, while cortisol adenoma was moderate in density and medium in size. Adrenocortical adenocarcinoma was the larger one with irregular margin and irregular hypodense areas inside. Metastatic carcinoma was larger and inhomogeneous in density. Conclusion: It is possible to increase the diagnostic rate by analysing the imaging feature of adrenal tumor

  18. Mass preserving image registration for lung CT

    DEFF Research Database (Denmark)

    Gorbunova, Vladlena; Sporring, Jon; Lo, Pechin Chien Pau

    2012-01-01

    This paper presents a mass preserving image registration algorithm for lung CT images. To account for the local change in lung tissue intensity during the breathing cycle, a tissue appearance model based on the principle of preservation of total lung mass is proposed. This model is incorporated...... on four groups of data: 44 pairs of longitudinal inspiratory chest CT scans with small difference in lung volume; 44 pairs of longitudinal inspiratory chest CT scans with large difference in lung volume; 16 pairs of expiratory and inspiratory CT scans; and 5 pairs of images extracted at end exhale and end...

  19. Diffusion-weighted magnetic resonance imaging in metastatic gastrointestinal stromal tumor (GIST) - A pilot study on the assessment of treatment response in comparison with 18F-FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Sabine; Koehli, Melanie; Meuli, Reto [Dept. of Radiology, Centre Hospitalier Universitaire Vaudois, Univ. of Lausanne, Lausanne (Switzerland)], e-mail: sabine.schmidt@chuv.ch; Dunet, Vincent; Prior, John O. [Dept. of Nuclear Medicine, Centre Hospitalier Universitaire Vaudois, Uniausanne, Lausanne (Switzerland); Montemurro, Michael [Dept. of Oncology, Centre Hospitalier Universitaire Vaudois (CHUV), Univ. of Lausanne, Lausanne (Switzerland)

    2013-10-15

    Background: Diffusion-weighted magnetic resonance imaging (MRI) is increasingly being used for assessing the treatment success in oncology, but the real clinical value needs to evaluated by comparison with other, already established, metabolic imaging techniques. Purpose: To prospectively evaluate the clinical potential of diffusion-weighted MRI with apparent diffusion coefficient (ADC) mapping for gastrointestinal stromal tumor (GIST) response to targeted therapy compared with 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). Material and Methods: Eight patients (mean age, 56{+-}11 years) known to have metastatic GIST underwent 18F-FDG PET/CT and MRI (T1Gd, DWI [b = 50,300,600], ADC mapping) simultaneously, before and after change in targeted therapy. MR and PET/CT examinations were first analyzed blindly. Second, PET/CT images were co-registered with T1Gd-MR images for lesion detection. Only 18F-FDG avid lesions were considered. Maximum standardized uptake value (SUV{sub max}) and the corresponding minimum ADC{sub min} were measured for the six largest lesions per patient, if any, on baseline and follow-up examinations. The relationship between changes in SUV{sub max} and ADCmin was analyzed (Spearman's correlation). Results: Twenty-four metastases (12 hepatic, 12 extra-hepatic) were compared on PET/CT and MR images. SUV{sub max} decreased from 7.7{+-}8.1 g/mL to 5.5{+-}5.4 g/mL (P = 0.20), while ADC{sub min} increased from 1.2{+-}0.3 X 10{sup -3}mm{sup 2}/s to 1.5{+-}0.3 X 10{sup -3}mm{sup 2}/s (P = 0.0002). There was a significant association between changes in SUV{sub max} and ADC{sub min} (rho = - 0.62, P = 0.0014), but not between changes in lesions size (P = 0.40). Conclusion: Changes in ADCmin correlated with the response of 18F-FDG avid GIST to targeted therapy. Thus, diffusion-weighted MRI may represent a radiation-free alternative for follow-up treatment for metastatic GIST patients.

  20. Imaging of female pelvic malignancies regarding MRI, CT, and PET/CT. Pt. 2

    International Nuclear Information System (INIS)

    Alt, Celine D.; Kauczor, Hans-Ulrich; Hallscheidt, Peter; Brocker, Kerstin A.; Eichbaum, Michael; Sohn, Christof; Arnegger, Florian U.

    2011-01-01

    To compose diagnostic standard operating procedures for both clinical and imaging assessment for vulvar and vaginal cancer, for vaginal sarcoma, and for ovarian cancer. The literature was reviewed for diagnosing the above mentioned malignancies in the female pelvis. Special focus herein lies in tumor representation in MRI, followed by the evaluation of CT and PET/CT for this topic. MRI is a useful additional diagnostic complement but by no means replaces established methods of gynecologic diagnostics and ultrasound. In fact, MRI is only implemented in the guidelines for vulvar cancer. According to the current literature, CT is still the cross-sectional imaging modality of choice for evaluating ovarian cancer. PET/CT appears to have advantages for staging and follow-up in sarcomas and cancers of the ovaries. (orig.)

  1. Imaging of benign tumors of the osseous spine

    OpenAIRE

    Riahi, Hend; Mechri, Meriem; Barsaoui, Maher; Bouaziz, Mouna; Vanhoenacker, Filip; Ladeb, Mohamed

    2018-01-01

    Abstract: The purpose of this paper is to present an overview of the imaging features of the most prevalent benign bone tumors involving the spine. Benign tumors of the osseous spine account approximately for 1% of all primary skeletal tumors. Many lesions exhibit characteristic radiologic features. In addition to age and location of the lesion, radiographs are an essential step in the initial detection and characterization but are limited to complex anatomy and superposition. CT and MR imagi...

  2. A theranostic nanoplatform: magneto-gold@fluorescence polymer nanoparticles for tumor targeting T1&T2-MRI/CT/NIR fluorescence imaging and induction of genuine autophagy mediated chemotherapy.

    Science.gov (United States)

    Wang, Guannan; Qian, Kun; Mei, Xifan

    2018-06-14

    Multifunctional nanoparticles, bearing low toxicity and tumor-targeting properties, coupled with multifunctional diagnostic imaging and enhanced treatment efficacy, have drawn tremendous attention due to their enormous potential for medical applications. Herein, we report a new kind of biocompatible and tumor-targeting magneto-gold@fluorescent polymer nanoparticle (MGFs-LyP-1), which is based on ultra-small magneto-gold (Fe 3 O 4 -Au) nanoparticles and NIR emissive fluorescent polymers by a solvent-mediated method. This kind of nanoparticle could be taken up efficiently and simultaneously serve for in vivo tumor targeting T 1 &T 2 -MRI/CT/near infrared (NIR) fluorescence bioimaging. Furthermore, the nanoparticles exhibit small size, higher tumor targeting accumulation, excellent cytocompatibility for long-term tracking, and no disturbing cell proliferation and differentiation. Moreover, clear and convincing evidence proves that as-synthesized MGFs-LyP-1 could elicit genuine autophagy via inducing autophagosome formation, which offers a definite synergistic effect to enhance cancer therapy with doxorubicin (DOX) at a nontoxic concentration through enhancement of the autophagy flux. Meanwhile, the as-prepared nanoparticles could be rapidly cleared from mice without any obvious organ impairment. The results indeed reveal a promising prospect of an MGFs-LyP-1 contrast agent with low toxicity and high efficiency for promising application in biomedicine.

  3. Imaging probe for tumor malignancy

    Science.gov (United States)

    Tanaka, Shotaro; Kizaka-Kondoh, Shinae; Hiraoka, Hasahiro

    2009-02-01

    Solid tumors possess unique microenvironments that are exposed to chronic hypoxic conditions ("tumor hypoxia"). Although more than half a century has passed since it was suggested that tumor hypoxia correlated with poor treatment outcomes and contributed to cancer recurrence, a fundamental solution to this problem has yet to be found. Hypoxia-inducible factor (HIF-1) is the main transcription factor that regulates the cellular response to hypoxia. It induces various genes whose functions are strongly associated with malignant alteration of the entire tumor. The cellular changes induced by HIF-1 are extremely important targets of cancer therapy, particularly in therapy against refractory cancers. Imaging of the HIF-1-active microenvironment is therefore important for cancer therapy. To image HIF-1activity in vivo, we developed a PTD-ODD fusion protein, POHA, which was uniquely labeled with near-infrared fluorescent dye at the C-terminal. POHA has two functional domains: protein transduction domain (PTD) and VHL-mediated protein destruction motif in oxygen-dependent degradation (ODD) domain of the alpha subunit of HIF-1 (HIF-1α). It can therefore be delivered to the entire body and remain stabilized in the HIF-1-active cells. When it was intravenously injected into tumor-bearing mice, a tumor-specific fluorescence signal was detected in the tumor 6 h after the injection. These results suggest that POHA can be used an imaging probe for tumor malignancy.

  4. (S)-4-(3-18F-fluoropropyl)-L-glutamic acid: an 18F-labeled tumor-specific probe for PET/CT imaging--dosimetry.

    Science.gov (United States)

    Smolarz, Kamilla; Krause, Bernd Joachim; Graner, Frank-Philipp; Wagner, Franziska Martina; Hultsch, Christina; Bacher-Stier, Claudia; Sparks, Richard B; Ramsay, Susan; Fels, Lüder M; Dinkelborg, Ludger M; Schwaiger, Markus

    2013-06-01

    The glutamic acid derivative (S)-4-(3-(18)F-Fluoropropyl)-l-glutamic acid ((18)F-FSPG, alias BAY 94-9392), a new PET tracer for the detection of malignant diseases, displayed promising results in non-small cell lung cancer patients. The aim of this study was to provide dosimetry estimates for (18)F-FSPG based on human whole-body PET/CT measurements. (18)F-FSPG was prepared by a fully automated 2-step procedure and purified by a solid-phase extraction method. PET/CT scans were obtained for 5 healthy volunteers (mean age, 59 y; age range, 51-64 y; 2 men, 3 women). Human subjects were imaged for up to 240 min using a PET/CT scanner after intravenous injection of 299 ± 22.5 MBq of (18)F-FSPG. Image quantification, time-activity data modeling, estimation of normalized number of disintegrations, and production of dosimetry estimates were performed using the RADAR (RAdiation Dose Assessment Resource) method for internal dosimetry and in general concordance with the methodology and principles as presented in the MIRD 16 document. Because of the renal excretion of the tracer, the absorbed dose was highest in the urinary bladder wall and kidneys, followed by the pancreas and uterus. The individual organ doses (mSv/MBq) were 0.40 ± 0.058 for the urinary bladder wall, 0.11 ± 0.011 for the kidneys, 0.077 ± 0.020 for the pancreas, and 0.030 ± 0.0034 for the uterus. The calculated effective dose was 0.032 ± 0.0034 mSv/MBq. Absorbed dose to the bladder and the effective dose can be reduced significantly by frequent bladder-voiding intervals. For a 0.75-h voiding interval, the bladder dose was reduced to 0.10 ± 0.012 mSv/MBq, and the effective dose was reduced to 0.015 ± 0.0010 mSv/MBq. On the basis of the distribution and biokinetic data, the determined radiation dose for (18)F-FSPG was calculated to be 9.5 ± 1.0 mSv at a patient dose of 300 MBq, which is of similar magnitude to that of (18)F-FDG (5.7 mSv). The effective dose can be reduced to 4.5 ± 0.30 mSv (at 300 MBq

  5. CT diagnosis of peritoneal metastasis tumor

    International Nuclear Information System (INIS)

    Deng Xueying; Chen Xiaoqi; Qi Le; Huang Feng

    2005-01-01

    Objective: To study the CT findings and diagnosis of peritoneal metastasis. Methods: The CT findings of 17 cases with surgical- pathologically proved peritoneal metastasis were analyzed retrospectively. Results The CT findings of peritoneal metastasis included: (1)ascites (12 cases ); (2)the aternation of parietal peritoneum including broad band thickening (7 cases), nodular sign (2 cases), and massive thickening (1 cases); (3) the involved omentum and mesenterium: 'smut' appearances (7 cases), nodular sign (2 cases), 'omental cake' (5 cases); (4) the invlovement of mesenteric vessels; (5) single-or multi-cystic lesions within peritoneum (1 case) . Conclusion: CT scan is the first choice for metastasis of peritoneum. (authors)

  6. Impact of the planning CT scan time on the reflection of the lung tumor motion

    International Nuclear Information System (INIS)

    Kim, Su San; Choi, Eun Kyung; Yi, Byong Yong; Ha, Sung Whan

    2004-01-01

    To evaluate the reflection of tumor motion according to the planning CT scan time. A model of N-shape, which moved along the longitudinal axis during the ventilation caused by a mechanical ventilator, was produced. The model was scanned by planning CT, while setting the relative CT scan time (T; CT scan time/ventilatory period) to 0.33, 0.50, 0.67, 0.75, 1.00, 1.33 T, and 1.53 T. In addition, three patients with non-small cell lung cancer who received stereotactic radiosurgery in the Department of Radiation Oncology, Asan Medical Center from 03/19/2002 to 05/21/2002 were scanned. Slow (IQ Premier, Picker, scan time 2.0 seconds per slice) and fast CT scans (Light Speed, GE Medical System, with a scan time of 0.8 second per slice) were performed for each patient. The magnitude of reflected movement of the N-shaped model was evaluated by measuring the transverse length, which reflected the movement of the declined bar of the model at each slice. For patients' scans, all CT data sets were registered using a stereotactic body frame scale with the gross tumor volumes delineated in one CT image set. The volume and three-dimensional diameter of the gross tumor volume were measured and analyzed between the slow and fast CT scans. The reflection degree of longitudinal movement of the model increased in proportion to the relative CT scan times below 1.00 T, but remained constant above 1.00 T. Assuming the mean value of scanned transverse lengths with CT scan time 1.00 T to be 100%, CT scans with scan times of 0.33, 0.50, 0.67, and 0.75 T missed the tumor motion by 30, 27, 20, and 7.0% respectively. Slow (scan time 2.0 sec) and Fast (scan time 0.8 sec) CT scans of three patients with longitudinal movement of 3, 5, and 10 mm measured by fluoroscopy revealed the increases in the diameter along the longitudinal axis increased by 6.3, 17, and 23% in the slow CT scans. As the relative CT scan time increased, the reflection of the respiratory tumor movement on planning CT also

  7. The performance and application of 18F-FDG PET/CT in diagnosis of tumor

    International Nuclear Information System (INIS)

    Wang Junqi

    2004-01-01

    Positron emission tomography (PET)/computed tomography (CT) inline scanner combined with high performance PET and CT have been introduced to clinical in recent years. The application of PET/CT in oncology are rapid increasing. The addition of CT to PET offers many advantages, including obtaining a fast and relatively accurate transmission map, shortening the duration of the examination, adding precise anatomical information to PET imaging, and providing additional diagnostic information. However, using CT for attenuation correction can led to some artifacts; quantitative measurements may be altered, high density IV and oral metallic objects may produce artifacts, and the registration of PET and CT may occasionally suboptimal. In head and neck tumor PET/CT offers particular potential advantages as well as abdomen and pelvic tumor. Even in the thorax, which the physical movement may produce unsatisfactory results, offers some advantages also. Preliminary results of PET/CT over PET or CT in oncology are very encouraging. It is clear the PET/CT fusion technology has an more and more impact on both diagnostic and therapeutic aspects of patient management

  8. Correlative Imaging in a Patient with Cystic Thymoma: CT, MR and PET/CT Comparison

    International Nuclear Information System (INIS)

    Romeo, Valeria; Esposito, Alfredo; Maurea, Simone; Camera, Luigi; Mainenti, Pier Paolo; Palmieri, Giovannella; Buonerba, Carlo; Salvatore, Marco

    2015-01-01

    Cystic thymoma is a rare variant of thymic neoplasm characterized by almost complete cystic degeneration with mixed internal structure. We describe a case of a 60 year-old woman with a cystic thymoma studied with advanced tomographic imaging stydies. CT, MRI and PET/CT with 18 F-FDG were performed; volumetric CT and MRI images provided better anatomic evaluation for pre-operative assessment, while PET/CT was helpful for lesion characterization based on 18 F-FDG uptake. Although imaging studies are mandatory for pre-operative evaluation of cystic thymoma, final diagnosis still remains surgical. A 60-year-old woman with recent chest pain and no history of previous disease was admitted to our departement to investigate the result of a previous chest X-ray that showed bilateral mediastinal enlargement; for this purpose, enhanced chest CT scan was performed using a 64-rows scanner (Toshiba, Aquilion 64, Japan) before and after intravenous bolus administration of iodinated non ionic contrast agent; CT images demonstrated the presence of a large mediastinal mass (11×8 cm) located in the anterior mediastinum who extended from the anonymous vein to the cardio-phrenic space, compressing the left atrium and causing medium lobe atelectasis; bilateral pleural effusion was also present. In conclusion, correlative imaging plays a foundamental role for the diagnostic evaluation of patient with cystic thymoma. In particular, volumetric CT and MRI studies can provide better anatomic informations regarding internal structure and local tumor spread for pre-operative assessment. Conversely, metabolic imaging using 18 F-FDG PET/CT is helpful for lesion characterization differentiating benign from malignant lesion on the basis of intense tracer uptake. The role of PET/MRI is still under investigation. However, final diagnosis still remains surgical even though imaging studies are mandatory for pre-operative patient management

  9. Diagnosis of pancreatic tumors by spiral angio CT

    International Nuclear Information System (INIS)

    Miura, Kohi; Nakao, Norio; Takayasu, Yukio; Okawa, Tomohisa

    1995-01-01

    Spiral angio were performed with injection of 30 ml of contrast material at a rate of 1 ml/sec with a scan delay of 6 sec through catheter into the celiac artery while the blood flow of the superior mesenteric artery (SMA) was occluded by the inflated balloon catheter. Spiral CT scans were obtained using Somatom Plus (Siemens). Parameter for spiral CT were 24-sec acquisition time, 5 mm collimation, 5 mm/sec table incrementation. Reconstructions were performed every 5 mm. Pancreatic cancers were characteristically depicted with spiral angio CT as hypodensity relative to normal enhanced pancreatic parenchyma. On dynamic angio CT studies performed in pancreatic cancers, the area of cancer and normal parenchyma had maximum level of enhancement at 10-15 sec after injection of contrast material via catheter into the celiac, and there was no difference in enhancement between tumor and normal parenchyma. On the other hand, the lesions of cancer were revealed as hypodensity with spiral angio CT. In case of chronic pancreatitis, the enhancement of the entire pancreas obtained with spiral angio CT was homogeneous. Insulinoma in the tail of pancreas was detected by spiral angio CT but was not detected by both selective angiography and conventional CT. Three-dimensional (3-D) rendering spiral angio CT data shows the extent of vascular involvement by pancreatic cancer and provides useful information for surgical planning. Spiral angio CT is the most useful procedure for diagnosis of pancreatic tumor. (author)

  10. 110 Subfascial lipomatous tumors. MR and CT findings versus histopathological diagnosis and cytogenetic analysis

    International Nuclear Information System (INIS)

    Einarsdottir, H.; Soederlund, V.; Larsson, O.; Mandahl, N.; Bauer, H.C.F.

    1999-01-01

    Purpose: To evaluate whether liposarcoma, atypical lipomatous tumors and lipoma can be differentiated radiologically. Material and Methods: We have retrospectively analyzed CT and/or MR images of 110 subfascial lipomatous lesions. The amount of fat within the tumors was visually graded from the images as: none, 1-75%, 75-95% or 95-100%. The structure of non-fatty tumor components was compared. The images were compared to histopathology and in 37 cases to cytogenetic findings. Results: Only 4 of 20 liposarcomas contained fat. All 4 lesions, histopathologically diagnosed as atypical lipomatous tumors, contained fat but less than 75% of tumor volume. All lesions with more fat than 75% of tumor volume were histologically diagnosed as lipomas. However, one-third of the karyotyped lipomas had ring chromosomes which are considered typical for atypical lipomatous tumors. Conclusion: When a tumor is composed more or less solely of fat, the diagnosis of a lipoma or atypical lipomatous tumor with a phenotype simulating a lipoma can be assumed. When the fat content is less than 75% of the tumor volume or non-fatty nodules are found, biopsies from different tumor components have to be performed to exclude malignancy. When no fat is found, imaging does not help in differentiating lipoma or liposarcoma from other soft tissue tumors. (orig.)

  11. Cross sectional imaging of cardiac tumors

    International Nuclear Information System (INIS)

    Maksimovic, R.

    2012-01-01

    Full text: Primary cardiac tumors are a rare entity whose incidence, according to surgery and autopsy reports, is 0.3% to 0.7% of all cardiac tumors. Metastasis to the heart from other primary cancers is 30 times more common. Only 25% of primary cardiac tumors are malignant, and, of these, 75% are sarcomas. Malignant primary cardiac sarcomas are usually located in the right atrium and are most commonly angiosarcoma. In the left atrium, the most common malignant tumors are pleomorphic sarcoma and leiomyosarcoma. Symptom presentation for cardiac tumors is quite varied, but it is dependent upon tumor location and size, rather than upon histologic characteristics. Presentation includes congestive heart failure from intracardiac obstruction, systemic embolization, constitutional symptoms, and arrhythmias. Left atrial sarcomas tend to be more solid and less infiltrative than right-sided sarcomas; consequently, they tend to metastasize later. They usually present with symptoms of blood-flow obstruction and substantial, life-threatening congestive heart failure. Right-sided cardiac tumors are usually malignant and appear as bulky, infiltrative masses that grow in an outward pattern. These are usually fast-growing tumors that metastasize early and do not present with congestive heart failure until late in the disease. The diagnosis of cardiac tumors relies heavily on the use of multiple imaging techniques, including cardiac computed tomography (CT), cardiovascular magnetic resonance (CMR), and echocardiography. Important imaging data to collect include information on the size of the intracardiac mass, the mobility of the mass (an important predictor of prognosis and embolic potential), myocardial invasion, and cardiac chamber location. These factors will provide the means to diagnosis and prognosis. Other important data to collect include the mechanism of tumor implantation, the relationship of the tumor with adjacent structures, the surgeon route of access to the heart

  12. Magnetic resonance imaging in 38 cases of acoustic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, Masafumi; Ohtsuka, Takashi; Seiki, Yoshikatsu; Matsumoto, Mikiro; Shibata, Iekado; Terao, Hideo [Toho Univ., Tokyo (Japan). School of Medicine; Kohno, Takeshi; Sanpei, Kenji; Mano, Isamu

    1989-08-01

    The value of magnetic resonance imaging (MRI) in the diagnosis of acoustic tumors was retrospectively assessed in 38 cases. A 0.15 Tesla permanent magnet and a 1.5 Tesla superconducting magnet were employed in 24 and 14 cases, respectively. Gadolinium diethlene triamine pentaacetic acid (Gd-DTPA), a paramagnetic contrast agent, was used in 10 cases. Acoustic tumors were identified in all cases. Small, medium, and large tumors were depicted with equal clarity by MRI and computed tomography (CT). However, tumor contour and extension, accompanying cysts, and brainstem displacement were more clarly visualized on MRI. The use of Gd-DTPA improved the quality of the MR images by markedly enhancing the acoustic tumors in all cases. In particular, detection of small acoustic tumors and intra- or paratumoral cysts was facilitated by the use of Gd-DTPA. The possibility of a correlation between acoustic tumor histology and MRI features was studied by calculation of the contrast to noise (C/N) ratio in 10 cases of acoustic tumor and 7 cases of meningioma. No definite correlation was demonstrated, but there appeared to be some difference in the C/N ratio between acoustic tumors and meningiomas. In three volunteers, MRI demonstrated intracanalicular nerves, separately. Because of its higher resolution, MRI can be expected to replace CT and air CT in the diagnosis of acoustic tumors. (author).

  13. Panoramic three-dimensional CT imaging

    International Nuclear Information System (INIS)

    Kawamata, Akitoshi; Fujishita, Masami

    1998-01-01

    Panoramic radiography is a unique projection technique for producing a single image of both maxillary and mandibular arches and many other anatomical structures. To obtain a similar panoramic image without panoramic radiography system, a modified three-dimensional (3D) CT imaging technique was designed. A set of CT slice image data extending from the chin to the orbit was used for 3D reconstruction. The CT machine used in this study was the X-Vision (TOSHIBA, Japan). The helical scan technique was used. The slice thickness of reconstructed image was one or 1.5 mm. The occlusal plane or Frankfort horizontal (FH) plane was used as the reference line. The resultant slice image data was stored on a magnetic optical disk and then used to create panoramic 3D-CT images on a Macintosh computer systems (Power Macintosh 8600/250, Apple Computer Inc., USA). To create the panoramic 3D-CT image, the following procedure was designed: Design a curved panoramic 3D-CT imaging layer using the imaging layer and the movement of the x-ray beam in panoramic radiography system as a template; Cut this imaging layer from each slice image, then the trimmed image was transformed to a rectangular layer using the ''still image warping'' special effect in the Elastic Reality special effects system (Elastic Reality Inc., USA); Create panoramic 3D-CT image using the Voxel View (Vital Images Inc., USA) rendering system and volume rendering technique. Although the image quality was primitive, a panoramic view of maxillofacial region was obtained by this technique. (author)

  14. Prognostic value of PET/CT in lung cancer. Study of survival and tumor metabolic characterization

    International Nuclear Information System (INIS)

    Ladron de Guevara, David; Fuentes Anibal; Farina, Ciro; Corral, Camilo; Pefaur, Raul

    2013-01-01

    PET/CT (Positron emission tomography/computed tomography) is a hybrid image modality widely used in oncology, for staging, therapy evaluation or follow up. Aim: To evaluate the prognostic value of PET/CT in lung cancer. Material and Methods: Retrospective review of PET/CT records, selecting 51 patients with a lung malignancy, mass or nodule referred for PET/CT between December 2008 and December 2010. All had pathological confirmation of malignancy and had not been treated previously. Age, gender, body mass index, radiological features of lung tumor and metastases, and lung tumor 18 F-fluoro-2-deoxy-d-glucose uptake using the SUV (Standardized uptake value) index were recorded. Survival was analyzed using Kaplan-Meier curves and a Cox proportional regression analysis. Results: Pathology confirmed the presence of lung cancer in 47 patients aged 30 to 88 years. Four patients (7.8%) had other type of tumors such as carcinoid or lymphoma. Fifty percent of lung cancer patients died during a mean observation lapse of 18 months (range: 2-34 months). Patients with metastases, local lymph node involvement, a lung tumor size ≥ 3 cm and high tumor uptake (SUVmax > 6) had significantly lower survival. Occurrence of metastases was the only independent prognostic factor in the Cox regression. A lung lesion with a SUVmax ≥ 12 was always associated to hilar/mediastinal lymph node involvement. Conclusions: PET/CT imaging gives important prognostic information in lung cancer patients

  15. Image Registration for PET/CT and CT Images with Particle Swarm Optimization

    International Nuclear Information System (INIS)

    Lee, Hak Jae; Kim, Yong Kwon; Lee, Ki Sung; Choi, Jong Hak; Kim, Chang Kyun; Moon, Guk Hyun; Joo, Sung Kwan; Kim, Kyeong Min; Cheon, Gi Jeong

    2009-01-01

    Image registration is a fundamental task in image processing used to match two or more images. It gives new information to the radiologists by matching images from different modalities. The objective of this study is to develop 2D image registration algorithm for PET/CT and CT images acquired by different systems at different times. We matched two CT images first (one from standalone CT and the other from PET/CT) that contain affluent anatomical information. Then, we geometrically transformed PET image according to the results of transformation parameters calculated by the previous step. We have used Affine transform to match the target and reference images. For the similarity measure, mutual information was explored. Use of particle swarm algorithm optimized the performance by finding the best matched parameter set within a reasonable amount of time. The results show good agreements of the images between PET/CT and CT. We expect the proposed algorithm can be used not only for PET/CT and CT image registration but also for different multi-modality imaging systems such as SPECT/CT, MRI/PET and so on.

  16. Computed tomography (CT) of the parapharyngeal space tumors

    Energy Technology Data Exchange (ETDEWEB)

    Kuriyama, K.; Narumi, Y.; Fujita, M.; Sato, T.; Kajita, A.; Sakai, Y.; Tanaka, H.; Nakanishi, K.; Fujino, Y.

    1987-04-01

    The parapharyngeal space is of great clinical importance. Because of its location deep within the neck, this space is difficult to be examined by ordinary methods but can be well demonstrated by CT. Ten patients with parapharyngeal space tumors were examined with CT. They consisted of 3 pleomorphic adenomas, 1 myoepitherioma, 1 metastatic lymphadenopathy, 1 branchial cleft cyst, 2 schwannomas, 1 neurofibroma and 1 branchiogenic carcinoma respectively. Parapharyngeal space is divided into parapharyngeal space (prestyloid space), carotid space (retrostyloid space), and retropharyngeal space. It is important to determine localization and mapping of parapharyngeal tumors, because the characteristic tumor types in histologic terms are found in each subdivision of parapharyngeal space.

  17. CT-criteria of orbital hemangiomas and their importance in differential diagnosis of intraconal tumors

    Energy Technology Data Exchange (ETDEWEB)

    Unsoeld, R; Hoyt, W F [California Univ., San Francisco (USA). Dept. of Neurosurgery; California Univ., San Francisco (USA). Dept. of Neurology and Opthalmology; California Univ., San Francisco (USA). Dept. of Neuroradiology)

    1979-12-01

    CT-Scans of 29 histologically proven cavernous hemangiomas were evaluated with respect to their location, shape, delineation from surrounding tissue, contrast-enhancement, and secondary changes of the bony orbit. Whenever a round or oval tumor, located in the outer upper muscle cone, sharply delineated from surrounding tissue, unattached to optic nerve and ocular muscles, spares a small triangular space in the orbital apex, it is in all probability a cavernous hemangioma. Evaluation of the tumors shape and its separation from surrounding tissues requires imaging in multiple sections in two planes oriented, if possible, at right angles. Changes in position of the optic nerve and eye muscles in different directions of gaze demonstrated by CT rule out significant tumor-attachments. The portion of the intraconal space least affected by optic nerve shifts and muscle contractions during eye movements, as demonstrated by CT, is the upper outer quadrant, the site preferred by the mobile tumor. Tumors which cannot be differentiated from cavernous hemangiomas by CT-criteria are rare usually benign. Reports of rare examples of well delineated or encapsulated malignant intraconal lesions indicate the possibility - however remote - of mistaking a malignant tumor for a cavernous hemangioma by CT.

  18. C-arm CT for chemo-embolization of liver tumors

    International Nuclear Information System (INIS)

    Huppert, P.E.; Firlbeck, G.; Meissner, O.A.; Wietholtz, H.

    2009-01-01

    Local efficacy of transarterial chemo-embolization (TACE) is enhanced if selective treatment is performed. Selectivity of TACE mainly depends on vascular anatomy but also on the identification and catheterization of tumor feeding arteries. Correlation of vascular territories and target tumor volume in angiographic projection images is more difficult if tumors are not hypervascularized and contrast of liver parenchyma is inhomogeneous. C-arm CT offers the option of selective perfusion imaging via tumor-feeding arteries. This allows the comparison of perfusion images and baseline cross-sectional imaging to evaluate if tumors are covered completely by local treatment and to change the catheter position if necessary. Furthermore the uptake of embolization material, such as lipiodol can be checked by C-arm CT. In a prospective study of 75 TACE of liver tumors and liver metastases we evaluated the appropriateness of 85 catheter positions ready for delivery by perfusion C-arm CT and compared the diagnostic confidence of angiography and perfusion C-arm CT in terms of judgment of correct catheter position for the planned treatment. Diagnostic confidence was improved by perfusion C-arm CT in 55% of cases and in 11 cases (13%) catheter positions were inappropriate and had to be corrected. The reasons for catheter repositioning were incomplete coverage of the target tumor by perfusion volume (mismatch) in 6 cases, inappropriate perfusion of adjacent liver parenchyma in 2 cases and non-selective tumor perfusion via collateral arteries in 3 cases. C-arm CT allowed sufficient visualization of uptake of lipiodol in all cases evaluated. The diagnostic benefit of C-arm CT increases if tumors are treated more selectively, are not strongly hypervascular, are located centrally and if the enhancement of liver parenchyma is inhomogeneous. C-arm CT causes additional working time and contrast load, which is relatively low compared to angiography. Radiation exposure of 151 μGy per C

  19. SPECT/CT workflow and imaging protocols

    Energy Technology Data Exchange (ETDEWEB)

    Beckers, Catherine [University Hospital of Liege, Division of Nuclear Medicine and Oncological Imaging, Department of Medical Physics, Liege (Belgium); Hustinx, Roland [University Hospital of Liege, Division of Nuclear Medicine and Oncological Imaging, Department of Medical Physics, Liege (Belgium); Domaine Universitaire du Sart Tilman, Service de Medecine Nucleaire et Imagerie Oncologique, CHU de Liege, Liege (Belgium)

    2014-05-15

    Introducing a hybrid imaging method such as single photon emission computed tomography (SPECT)/CT greatly alters the routine in the nuclear medicine department. It requires designing new workflow processes and the revision of original scheduling process and imaging protocols. In addition, the imaging protocol should be adapted for each individual patient, so that performing CT is fully justified and the CT procedure is fully tailored to address the clinical issue. Such refinements often occur before the procedure is started but may be required at some intermediate stage of the procedure. Furthermore, SPECT/CT leads in many instances to a new partnership with the radiology department. This article presents practical advice and highlights the key clinical elements which need to be considered to help understand the workflow process of SPECT/CT and optimise imaging protocols. The workflow process using SPECT/CT is complex in particular because of its bimodal character, the large spectrum of stakeholders, the multiplicity of their activities at various time points and the need for real-time decision-making. With help from analytical tools developed for quality assessment, the workflow process using SPECT/CT may be separated into related, but independent steps, each with its specific human and material resources to use as inputs or outputs. This helps identify factors that could contribute to failure in routine clinical practice. At each step of the process, practical aspects to optimise imaging procedure and protocols are developed. A decision-making algorithm for justifying each CT indication as well as the appropriateness of each CT protocol is the cornerstone of routine clinical practice using SPECT/CT. In conclusion, implementing hybrid SPECT/CT imaging requires new ways of working. It is highly rewarding from a clinical perspective, but it also proves to be a daily challenge in terms of management. (orig.)

  20. SPECT/CT workflow and imaging protocols

    International Nuclear Information System (INIS)

    Beckers, Catherine; Hustinx, Roland

    2014-01-01

    Introducing a hybrid imaging method such as single photon emission computed tomography (SPECT)/CT greatly alters the routine in the nuclear medicine department. It requires designing new workflow processes and the revision of original scheduling process and imaging protocols. In addition, the imaging protocol should be adapted for each individual patient, so that performing CT is fully justified and the CT procedure is fully tailored to address the clinical issue. Such refinements often occur before the procedure is started but may be required at some intermediate stage of the procedure. Furthermore, SPECT/CT leads in many instances to a new partnership with the radiology department. This article presents practical advice and highlights the key clinical elements which need to be considered to help understand the workflow process of SPECT/CT and optimise imaging protocols. The workflow process using SPECT/CT is complex in particular because of its bimodal character, the large spectrum of stakeholders, the multiplicity of their activities at various time points and the need for real-time decision-making. With help from analytical tools developed for quality assessment, the workflow process using SPECT/CT may be separated into related, but independent steps, each with its specific human and material resources to use as inputs or outputs. This helps identify factors that could contribute to failure in routine clinical practice. At each step of the process, practical aspects to optimise imaging procedure and protocols are developed. A decision-making algorithm for justifying each CT indication as well as the appropriateness of each CT protocol is the cornerstone of routine clinical practice using SPECT/CT. In conclusion, implementing hybrid SPECT/CT imaging requires new ways of working. It is highly rewarding from a clinical perspective, but it also proves to be a daily challenge in terms of management. (orig.)

  1. Using 18F FDG PET/CT to Detect an occult Mesenchymal Tumor Causing Oncogenic Osteomalacia

    International Nuclear Information System (INIS)

    Seo, Hyo Jung; Choi, Yun Jung; Kim, Hyun Jeong; Jeong, Yong Hyu; Cho, Arthur; Lee, Jae Hoon; Yun, Mijin; Lee, Jong Doo; Kang, Won Jun

    2011-01-01

    Oncogenic osteomalacia is a rare paraneoplastic syndrome characterized by renal phosphate excretion, hypophosphatemia, and osteomalacia. This syndrome is often caused by tumors of mesenchymal origin. Patients with oncogenic osteomalacia have abnormal bone mineralization, resulting in a high frequency of fractures. Tumor resection is the treatment of choice, as it will often correct the metabolic imbalance. Although oncogenic osteomalacia is a potentially curable disease, diagnosis is difficult and often delayed because of the small size and sporadic location of the tumor. Bone scintigraphy and radiography best characterize osteoma lacia; magnetic resonance imaging findings are nonspecific. Here, we report a case of oncogenic osteomalacia secondary to a phosphaturic mesenchymal tumor that was successfully detected by 18F fluorodeoxyglucose positron emission tomography/computed tomography ( 18F FDG PET/CT). This case illustrates the advantages of 18F FDG PET/CT in detecting the occult mesenchymal tumor that causes oncogenic osteomalacia.

  2. Gene transcript analysis blood values correlate with {sup 68}Ga-DOTA-somatostatin analog (SSA) PET/CT imaging in neuroendocrine tumors and can define disease status

    Energy Technology Data Exchange (ETDEWEB)

    Bodei, L. [European Institute of Oncology, Division of Nuclear Medicine, Milan (Italy); Kidd, M.; Modlin, I.M.; Drozdov, I. [Wren Laboratories, Branford, CT (United States); Prasad, V. [Charite University Hospital, Department of Nuclear Medicine, Berlin (Germany); Severi, S.; Paganelli, G. [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Nuclear Medicine and Radiometabolic Units, Meldola (Italy); Ambrosini, V. [S. Orsola-Malpighi University Hospital, Nuclear Medicine, Bologna (Italy); Kwekkeboom, D.J.; Krenning, E.P. [Erasmus Medical Center Rotterdam, Nuclear Medicine Department, Rotterdam (Netherlands); Baum, R.P. [Zentralklinik Bad Berka, THERANOSTICS Center for Molecular Radiotherapy and Imaging, Bad Berka (Germany)

    2015-08-15

    Precise determination of neuroendocrine tumor (NET) disease status and response to therapy remains a rate-limiting concern for disease management. This reflects limitations in biomarker specificity and resolution capacity of imaging. In order to evaluate biomarker precision and identify if combinatorial blood molecular markers and imaging could provide added diagnostic value, we assessed the concordance between {sup 68}Ga-somatostatin analog (SSA) positron emission tomography (PET), circulating NET gene transcripts (NETest), chromogranin A (CgA), and Ki-67 in NETs. We utilized two independent patient groups with positive {sup 68}Ga-SSA PET: data set 1 ({sup 68}Ga-SSA PETs undertaken for peptide receptor radionuclide therapy (PRRT), as primary or salvage treatment, n = 27) and data set 2 ({sup 68}Ga-SSA PETs performed in patients referred for initial disease staging or restaging after various therapies, n = 22). We examined the maximum standardized uptake value (SUV{sub max}), circulating gene transcripts, CgA levels, and baseline Ki-67. Regression analyses, generalized linear modeling, and receiver-operating characteristic (ROC) analyses were undertaken to determine the strength of the relationships. SUV{sub max} measured in two centers were mathematically evaluated (regression modeling) and determined to be comparable. Of 49 patients, 47 (96 %) exhibited a positive NETest. Twenty-six (54 %) had elevated CgA (χ{sup 2} = 20.1, p < 2.5 x 10{sup -6}). The majority (78 %) had Ki-67 < 20 %. Gene transcript scores were predictive of imaging with >95 % concordance and significantly correlated with SUV{sub max} (R {sup 2} = 0.31, root-mean-square error = 9.4). The genes MORF4L2 and somatostatin receptors SSTR1, 3, and 5 exhibited the highest correlation with SUV{sub max}. Progressive disease was identified by elevated levels of a quotient of MORF4L2 expression and SUV{sub max} [ROC-derived AUC (R {sup 2} = 0.7, p < 0.05)]. No statistical relationship was identified

  3. Gene transcript analysis blood values correlate with 68Ga-DOTA-somatostatin analog (SSA) PET/CT imaging in neuroendocrine tumors and can define disease status

    International Nuclear Information System (INIS)

    Bodei, L.; Kidd, M.; Modlin, I.M.; Drozdov, I.; Prasad, V.; Severi, S.; Paganelli, G.; Ambrosini, V.; Kwekkeboom, D.J.; Krenning, E.P.; Baum, R.P.

    2015-01-01

    Precise determination of neuroendocrine tumor (NET) disease status and response to therapy remains a rate-limiting concern for disease management. This reflects limitations in biomarker specificity and resolution capacity of imaging. In order to evaluate biomarker precision and identify if combinatorial blood molecular markers and imaging could provide added diagnostic value, we assessed the concordance between 68 Ga-somatostatin analog (SSA) positron emission tomography (PET), circulating NET gene transcripts (NETest), chromogranin A (CgA), and Ki-67 in NETs. We utilized two independent patient groups with positive 68 Ga-SSA PET: data set 1 ( 68 Ga-SSA PETs undertaken for peptide receptor radionuclide therapy (PRRT), as primary or salvage treatment, n = 27) and data set 2 ( 68 Ga-SSA PETs performed in patients referred for initial disease staging or restaging after various therapies, n = 22). We examined the maximum standardized uptake value (SUV max ), circulating gene transcripts, CgA levels, and baseline Ki-67. Regression analyses, generalized linear modeling, and receiver-operating characteristic (ROC) analyses were undertaken to determine the strength of the relationships. SUV max measured in two centers were mathematically evaluated (regression modeling) and determined to be comparable. Of 49 patients, 47 (96 %) exhibited a positive NETest. Twenty-six (54 %) had elevated CgA (χ 2 = 20.1, p < 2.5 x 10 -6 ). The majority (78 %) had Ki-67 < 20 %. Gene transcript scores were predictive of imaging with >95 % concordance and significantly correlated with SUV max (R 2 = 0.31, root-mean-square error = 9.4). The genes MORF4L2 and somatostatin receptors SSTR1, 3, and 5 exhibited the highest correlation with SUV max . Progressive disease was identified by elevated levels of a quotient of MORF4L2 expression and SUV max [ROC-derived AUC (R 2 = 0.7, p < 0.05)]. No statistical relationship was identified between CgA and Ki-67 and no relationship with imaging parameters

  4. Tumor imaging with monoclonal antibodies

    International Nuclear Information System (INIS)

    Haisma, H.; Hilgers, J.

    1987-01-01

    Many monoclonal antibodies directed against tumor-associated antigens have been identified, but so far none of these are tumor specific. Polyclonal and monoclonal antibodies have been used for imaging of a wide variety of tumors with success. Radiolabeling of antibody is usually done with iodine isotopes of which 123 I is the best candidate for radioimmunodetection purposes. The labeling of antibodies through chelates makes it possible to use metal radioisotopes like 111 In, which is the best radioisotope for imaging with monoclonal antibodies due to its favorable half-life of 2.5 days. Usually imaging cannot be performed within 24 h after injection, but clearance of antibody can be increased by using F(ab) 2 of Fab. Another approach is to clear non-bound antibody by a second antibody, directed against the first. The detection limit of immunoimaging is about 2 cm, but will be improved by tomography or SPECT. There is still a high false positive and false negative rate, which makes it impossible to use radioimmunodetection as the only technique for diagnosis of tumors. In combination with other detection techniques, tumor imaging with monoclonal antibodies can improve diagnosis. 44 refs.; 3 tabs

  5. CT image construction of a totally deflated lung using deformable model extrapolation

    International Nuclear Information System (INIS)

    Sadeghi Naini, Ali; Pierce, Greg; Lee, Ting-Yim

    2011-01-01

    Purpose: A novel technique is proposed to construct CT image of a totally deflated lung from a free-breathing 4D-CT image sequence acquired preoperatively. Such a constructed CT image is very useful in performing tumor ablative procedures such as lung brachytherapy. Tumor ablative procedures are frequently performed while the lung is totally deflated. Deflating the lung during such procedures renders preoperative images ineffective for targeting the tumor. Furthermore, the problem cannot be solved using intraoperative ultrasound (U.S.) images because U.S. images are very sensitive to small residual amount of air remaining in the deflated lung. One possible solution to address these issues is to register high quality preoperative CT images of the deflated lung with their corresponding low quality intraoperative U.S. images. However, given that such preoperative images correspond to an inflated lung, such CT images need to be processed to construct CT images pertaining to the lung's deflated state. Methods: To obtain the CT images of deflated lung, we present a novel image construction technique using extrapolated deformable registration to predict the deformation the lung undergoes during full deflation. The proposed construction technique involves estimating the lung's air volume in each preoperative image automatically in order to track the respiration phase of each 4D-CT image throughout a respiratory cycle; i.e., the technique does not need any external marker to form a respiratory signal in the process of curve fitting and extrapolation. The extrapolated deformation field is then applied on a preoperative reference image in order to construct the totally deflated lung's CT image. The technique was evaluated experimentally using ex vivo porcine lung. Results: The ex vivo lung experiments led to very encouraging results. In comparison with the CT image of the deflated lung we acquired for the purpose of validation, the constructed CT image was very similar. The

  6. Liver tumors, correlation of computed tomography (CT) and pathology

    Energy Technology Data Exchange (ETDEWEB)

    Okazaki, Atsushi; Niibe, Hideo; Mitsuhashi, Norio

    1984-09-01

    Computed tomographic and pathologic correlation was studied in 12 autopsied cases with 11 cases of metastatic liver tumors and 1 case of hepatocellular carcinoma. Despite of proliferative patterns of the tumors, nodular low attenuations on CT showed scattered nodular lesions and geographic low attenuations on CT showed groups of multiple small nodular lesions, macroscopically. Abnormal areas of low attenuation were generally diminished by drip infusion contrast enhancement, which was more significant on tumors of infiltrative proliferation. Tumors of infiltrative proliferation revealed little degeneration of surrounding liver cells and abnormal areas of low attenuation were more distinct before contrast enhancement. Tumors of expansive proliferation revealed obvious degeneration of surrounding liver cells and a case having about 200 layers of degenerated liver cells revealed more distinct after contrast enhancement. The central lower density areas in abnormal areas of low attenuation on CT coincided with liquefactive necroses with scanty capillary. vessels and fibrotic changes, histopathologically. But coagulative necroses without decrease of surrouding blood flows were not visualized on CT. CT could not demonstrate the liquefactive necroses in more small nodules than 2 cm in diameter. (J.P.N.).

  7. Bone tumors

    International Nuclear Information System (INIS)

    Unni, K.K.

    1988-01-01

    This book contains the proceedings on bone tumors. Topics covered include: Bone tumor imaging: Contribution of CT and MRI, staging of bone tumors, perind cell tumors of bone, and metastatic bone disease

  8. Intracranial solitary fibrous tumor: Imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Clarencon, Frederic, E-mail: fredclare5@msn.com [Department of Neuroradiology, Pitie-Salpetriere Hospital, APHP, 75013 Paris (France); Bonneville, Fabrice [Department of Neuroradiology, Hopital Rangueil, Toulouse University Hospital, 31000 Toulouse (France); Rousseau, Audrey [Department of Neuropathology, Pitie-Salpetriere Hospital (France); Galanaud, Damien [Department of Neuroradiology, Pitie-Salpetriere Hospital, APHP, 75013 Paris (France); Kujas, Michele [Department of Neuropathology, Pitie-Salpetriere Hospital (France); Naggara, Olivier [Department of Neuroradiology, St Anne Hospital, 75014 Paris (France); Cornu, Philippe [Department of Neurosurgery, Pitie-Salpetriere Hospital (France); Chiras, Jacques [Department of Neuroradiology, Pitie-Salpetriere Hospital, APHP, 75013 Paris (France)

    2011-11-15

    Objective: To study the neuroimaging features of intracranial solitary fibrous tumors (ISFTs). Materials and methods: Retrospective study of neuroimaging features of 9 consecutive histopathologically proven ISFT cases. Location, size, shape, density, signal intensity and gadolinium uptake were studied at CT and MRI. Data collected from diffusion-weighted imaging (DWI) (3 patients), perfusion imaging and MR spectroscopy (2 patients), and DSA (4 patients) were also analyzed. Results: The tumors most frequently arose from the intracranial meninges (7/9), while the other lesions were intraventricular. Tumor size ranged from 2.5 to 10 cm (mean = 6.6 cm). They presented multilobular shape in 6/9 patients. Most ISFTs were heterogeneous (7/9) with areas of low T2 signal intensity that strongly enhanced after gadolinium administration (6/8). Erosion of the skull was present in about half of the cases (4/9). Components with decreased apparent diffusion coefficient were seen in 2/3 ISFTs on DWI. Spectroscopy revealed elevated peaks of choline and myo-inositol. MR perfusion showed features of hyperperfusion. Conclusion: ISFT should be considered in cases of extra-axial, supratentorial, heterogeneous, hypervascular tumor. Areas of low T2 signal intensity that strongly enhance after gadolinium injection are suggestive of this diagnosis. Restricted diffusion and elevated peak of myo-inositol may be additional valuable features.

  9. Brain tumors and CT scans in infants and children, (3)

    International Nuclear Information System (INIS)

    Oi, Shizuo

    1983-01-01

    In clinical pictures of brain tumors in infants and children, many features are not identical to those in adults, including characteristics of the tumors in age population, the locations of the tumors, the clinical symptoms and signs, and various factors affecting prognosis. We have, therefore, clinically and extensively analyzed brain tumors in infants and children. This study was also performed in order to analyze the characteristic CT findings of astrocytoma, the tumor most frequently occurring among infants and children. The subjects were 24 cases of astrocytoma and 2 cases of glioblastoma in infants and children under 16 years. The locations and characteristics of the tumors were as follows. Most of the tumors occurred in the 4th ventricle, had a characteristic low density, and could almost entirely be clearly distinguished from medulloblastomas, but not from ependymomas, on CT. The features of the supratentorial tumors were similar to those of the astrocytomas and glioblastomas mostly appearing in adults, as previously reported, in the relatively close correlation with the location and malignancy of the tumor. There was also a case of diffuse astrocytoma, a ''non-enhanced low-density solid tumor,'' which raised clinical problems. Among low-grade astrocytomas in infants and children, only a few show a high density on plain CT, many have, at least macroscopically, a strong contrast enhancement, and peritumoral edema is not observed on CT or, if observed, is observed only slightly. As individual features, homogenous enhancement pattern, a mixed density, a central low density, and a rare absence of enhancement are listed. (author)

  10. Prevalence of Os Trigonum on CT Imaging

    NARCIS (Netherlands)

    Zwiers, Ruben; Baltes, Thomas P. A.; Opdam, Kim T. M.; Wiegerinck, Johannes I.; van Dijk, C. Niek

    2017-01-01

    The os trigonum is known as one of the main causes of posterior ankle impingement. In the literature, a wide variation of occurrence has been reported. All foot and/or ankle computed tomography (CT) scans made between January 2012 and December 2013 were reviewed. CT images were assessed, blinded for

  11. Diagnostic difficulties in the differentiation of neurogenic tumors of the parapharyngeal space in helical CT evaluations: A case report

    International Nuclear Information System (INIS)

    Czerniewicz-Kaminska, A.; Nowicki, J.; Jazwiec, P.; Kedzierski, B.; Janeczek, T.; Wilczynski, K.; Prudlak, E.

    2005-01-01

    Computerized tomography (CT) with contrast infusion and magnetic resonance imaging (MRI) play important roles in establishing the place of origin of neurogenic tumors. In this article we do not compare these two methods, but focus on the crucial role of CT imaging in the estimation and differential diagnosis of these tumors. We present the case of a 50-year-old man with clinical symptoms of peritonsillar abscess, which appeared to be a neurogenic tumor. The images obtained were deemed ambiguous. The possibility of a parotid gland tumor or a tumor of neurogenic origin was assumed. In this case we observed atypical clinical and radiological symptoms. The final diagnosis was based on a combination of radiological, clinical, and microbiological features of the tumor. Thanks to the cooperation of many professionals, we managed to establish the diagnosis of neuroangiofibroma, which exemplifies a tumor of the borderline, including elements of the neurogenic sheath and connective and chromaffin tissue. (author)

  12. Percutaneous CT-guided high-dose brachytherapy (CT-HDRBT) ablation of primary and metastatic lung tumors in nonsurgical candidates; Perkutane CT-gesteuerte Hochdosis-Brachytherapie (CT-HDRBT) von primaeren und metastatischen Lungentumoren in nicht chirurgischen Kandidaten

    Energy Technology Data Exchange (ETDEWEB)

    Collettini, F.; Schnapauff, D.; Poellinger, A.; Denecke, T.; Banzer, J.; Golenia, M.J.; Gebauer, B. [Charite - Universitatesmedizin Berlin (Germany). Inst. fuer Radiologie; Wust, P. [Charite - Universitatesmedizin Berlin (Germany). Klinik fuer Strahlentherapie

    2012-04-15

    To evaluate the safety and efficacy of CT-guided high-dose brachytherapy (CT-HDRBT) ablation of primary and metastatic lung tumors. Between November 2007 and May 2010, all consecutive patients with primary or metastatic lung tumors, unsuitable for surgery, were treated with CT-HDRBT. Imaging follow-up after treatment was performed with contrast-enhanced CT at 6 weeks, 3 months and every 6 months after the procedure. The endpoints of the study were local tumor control and time to progression. The Kaplan-Meier method was used to estimate survival functions and local tumor progression rates. 34 procedures were carried out on 33 lesions in 22 patients. The mean diameter of the tumors was 33.3 mm (SD = 20.4). The first contrast-enhanced CT showed that complete ablation was achieved in all lesions. The mean minimal tumor enclosing dose was 18.9 Gy (SD = 2). Three patients developed a pneumothorax after the procedure. The mean follow-up time was 13.7 (3 - 29) months. 2 of 32 lesions (6.25 %) developed a local tumor progression. 8 patients (36.3 %) developed a distant tumor progression. After 17.7 months, 13 patients were alive and 9 patients had died. CT-HDRBT ablation is a safe and attractive treatment option for patients with lung malignancies and allows targeted destruction of tumor tissue with simultaneous preservation of important lung structures. Furthermore, CT-HDRBT is independent of the size of the lesion and its location within the lung parenchyma. (orig.)

  13. The diagnosis of intracranial tumors by CT (computerized tomography) from a practical point of view

    International Nuclear Information System (INIS)

    Elke, M.; Wiggli, U.; Huenig, R.

    1977-01-01

    In a historical abstract the mathematical basis of image reconstruction techniques and CT is reviewed. The enhancement of iodine contrast media is essential in CT diagnostis of space occupying intracranial lesions. Intracranial tumors usually show relatively characteristical but mostly non-specific absorption patterns. Additional clinical information is necessary for differential diagnostic evalution. The development of tables with various tumor patterns is recommended. Absorption feature of primary and secondary brain-tumors with the surrounding edema is explained. Glioblastomas as well as metastases often show a distinct cerebral edema which has been observed in 64% of our patients with metastases and distinctly localized high dense foci in 69%. 6,000 patients were investigated by CT and 1,708 examinations were performed with contrast enhancement. Side-effects are within the known reaction of other intravenously applicated contrast media. (orig.) [de

  14. Diagnosis of intracranial tumors by CT (computerized tomography) from a practical point of view

    Energy Technology Data Exchange (ETDEWEB)

    Elke, M; Wiggli, U; Huenig, R [Basel Univ. (Switzerland). Inst. fuer Medizinische Radiologie

    1977-04-01

    In a historical abstract the mathematical basis of image reconstruction techniques and CT is reviewed. The enhancement of iodine contrast media is essential in CT diagnostis of space occupying intracranial lesions. Intracranial tumors usually show relatively characteristical but mostly non-specific absorption patterns. Additional clinical information is necessary for differential diagnostic evalution. The development of tables with various tumor patterns is recommended. Absorption feature of primary and secondary brain-tumors with the surrounding edema is explained. Glioblastomas as well as metastases often show a distinct cerebral edema which has been observed in 64% of our patients with metastases and distinctly localized high dense foci in 69%. 6,000 patients were investigated by CT and 1,708 examinations were performed with contrast enhancement. Side-effects are within the known reaction of other intravenously applicated contrast media.

  15. The stylohyoid chain: CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Uysal Ramadan, Selma, E-mail: uysalselma@yahoo.co [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey); Goekharman, Dilek, E-mail: gokharman@ttnet.net.t [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey); Kosar, Pinar, E-mail: pkosar@hotmail.co [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey); Kacar, Mahmut, E-mail: mkacar1961@gamil.co [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey); Kosar, Ugur, E-mail: ugurkosar@hotmail.co [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey)

    2010-09-15

    We aimed in this report to discuss the embryology, anatomy, theories of ossification and symptoms, clinical presentation, and diagnosis of the stylohyoid chain (SHC) variations, together with the role of radiographs, computed tomography (CT) and three-dimensional (3D)-CT in showing these variations. Because CT/3D-CT additionally facilitates visualization of the entire SHC with different axes, it is the most valuable method for establishing the relationship between the SHC and the surrounding tissue. SHC variation can be discovered during CT performed for indications other than ossified SHC. It is important to diagnose whether or not the SHC is ossified, since one of the treatment procedures in ossified SHC is total excision. If the clinician and radiologist are aware of these variations observed in the SHC, patients with vague symptoms may be spared unnecessary investigations and may be properly diagnosed earlier.

  16. CT and MR imaging findings of sphenoidal masses

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Shoki; Higano, Shuichi (Tohoku Univ., Sendai (Japan). School of Medicine); Ishii, Kiyoshi (and others)

    1994-07-01

    CT and MR imaging findings of 57 sphenoidal masses were retrospectively reviewed to assess the possibility of differential diagnosis between them. Various kinds of masses such as pituitary adenoma, epipharyngeal cancer, mucocele, chordoma, chondroma, chondrosarcoma, distant metastasis, multiple myeloma, fibrous dysplasia, craniopharyngioma, hemangiopericytoma, giant cell tumor, primary sphenoidal cancer, malignant melanoma, leukemia, histiocytosis X, and giant cell tumor were included in this series. CT scanning was performed in all cases using a spin-echo pulse sequence. The relative density of the masses, bony changes and calcification were evaluated on CT, and on MR images, signal intensity of the masses relative to the normal gray matter, contrast enhancement and extension/contour were evaluated. Although no single feature appeared to be specific to the masses, detection of calcification on CT, identification of the normal pituitary gland as deformed or displaced on T1-weighted images, signal intensity on T2-weighted images, and extension of the masses seemed to be useful and should be examined in terms of their ability to assist in differential diagnosis. Finally, accommodative classification of sphenoidal masses primarily based on presumed origin or mode of extension was attempted. (author).

  17. Predicting tumor hypoxia in non-small cell lung cancer by combining CT, FDG PET and dynamic contrast-enhanced CT.

    Science.gov (United States)

    Even, Aniek J G; Reymen, Bart; La Fontaine, Matthew D; Das, Marco; Jochems, Arthur; Mottaghy, Felix M; Belderbos, José S A; De Ruysscher, Dirk; Lambin, Philippe; van Elmpt, Wouter

    2017-11-01

    Most solid tumors contain inadequately oxygenated (i.e., hypoxic) regions, which tend to be more aggressive and treatment resistant. Hypoxia PET allows visualization of hypoxia and may enable treatment adaptation. However, hypoxia PET imaging is expensive, time-consuming and not widely available. We aimed to predict hypoxia levels in non-small cell lung cancer (NSCLC) using more easily available imaging modalities: FDG-PET/CT and dynamic contrast-enhanced CT (DCE-CT). For 34 NSCLC patients, included in two clinical trials, hypoxia HX4-PET/CT, planning FDG-PET/CT and DCE-CT scans were acquired before radiotherapy. Scans were non-rigidly registered to the planning CT. Tumor blood flow (BF) and blood volume (BV) were calculated by kinetic analysis of DCE-CT images. Within the gross tumor volume, independent clusters, i.e., supervoxels, were created based on FDG-PET/CT. For each supervoxel, tumor-to-background ratios (TBR) were calculated (median SUV/aorta SUV mean ) for HX4-PET/CT and supervoxel features (median, SD, entropy) for the other modalities. Two random forest models (cross-validated: 10 folds, five repeats) were trained to predict the hypoxia TBR; one based on CT, FDG, BF and BV, and one with only CT and FDG features. Patients were split in a training (trial NCT01024829) and independent test set (trial NCT01210378). For each patient, predicted, and observed hypoxic volumes (HV) (TBR > 1.2) were compared. Fifteen patients (3291 supervoxels) were used for training and 19 patients (1502 supervoxels) for testing. The model with all features (RMSE training: 0.19 ± 0.01, test: 0.27) outperformed the model with only CT and FDG-PET features (RMSE training: 0.20 ± 0.01, test: 0.29). All tumors of the test set were correctly classified as normoxic or hypoxic (HV > 1 cm 3 ) by the best performing model. We created a data-driven methodology to predict hypoxia levels and hypoxia spatial patterns using CT, FDG-PET and DCE-CT features in NSCLC. The

  18. Differentiation between tuberculosis and primary tumors in the adrenal gland: evaluation with contrast-enhanced CT

    International Nuclear Information System (INIS)

    Yang, Zhi-Gang; Guo, Ying-Kun; Li, Yuan; Min, Peng-Qiu; Yu, Jian-Qun; Ma, En-Sen

    2006-01-01

    The aim of the present study is to determine imaging criteria for differentiating tuberculosis from primary tumors in the adrenal gland on contrast-enhanced CT. Non-contrast and contrast-enhanced CT features in 108 patients with adrenal tuberculosis (n=34) and primary tumor (n=74) were retrospectively assessed for the location, size, calcification and enhancement patterns. The primary tumors included 41 adenomas, 11 pheochromocytomas, 4 carcinomas, 3 lymphomas, 6 myelolipomas, 6 ganglioneuromas, 2 neurilemmomas and 1 ganglioneuroblastoma. Biochemical investigation was performed for all patients. Of the tuberculosis cases, 31 (91%) invaded with bilateral involvement, while 7 (9%) of the primary tumors invaded with bilateral involvement (P<0.001). Tuberculosis often showed calcification (20 of 34; 59%), whereas primary tumors infrequently showed calcification (6 of 74; 8%; P<0.001). Low attenuation in the center with peripheral rim enhancement was more commonly seen in tuberculosis (16 of 34; 47%) than in primary tumors (7 of 74; 9%; P<0.001). In the determination of tuberculosis, the highest sensitivity (91%) and accuracy (91%) were obtained with bilateral involvement, and the highest specificity (99%) was obtained with the contour preserved. In the determination of primary tumors using a combination of having unilateral involvement and being mass-like, the outcome was a sensitivity of 91%, specificity of 94% and accuracy of 92%. CT findings can differentiate tuberculosis from a primary tumor of the adrenal glands with high sensitivity and an acceptable specificity when combined with the endocrinological examination. (orig.)

  19. Cochlear anatomy: CT and MR imaging

    International Nuclear Information System (INIS)

    Martinez, Manuel; Bruno, Claudio; Martin, Eduardo; Canale, Nancy; De Luca, Laura; Spina, Juan C. h

    2002-01-01

    The authors present a brief overview of the normal cochlear anatomy with CT and MR images in order to allow a more complete identification of the pathological findings in patients with perceptive hipoacusia. (author)

  20. Three-dimensional reconstruction of CT images

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Toshiaki; Kattoh, Keiichi; Kawakami, Genichiroh; Igami, Isao; Mariya, Yasushi; Nakamura, Yasuhiko; Saitoh, Yohko; Tamura, Koreroku; Shinozaki, Tatsuyo

    1986-09-01

    Computed tomography (CT) has the ability to provide sensitive visualization of organs and lesions. Owing to the nature of CT to be transaxial images, a structure which is greater than a certain size appears as several serial CT images. Consequently each observer must reconstruct those images into a three-dimensional (3-D) form mentally. It has been supposed to be of great use if such a 3-D form can be described as a definite figure. A new computer program has been developed which can produce 3-D figures from the profiles of organs and lesions on CT images using spline curves. The figures obtained through this method are regarded to have practical applications.

  1. SU-G-IeP4-11: Monitoring Tumor Growth in Subcutaneous Murine Tumor Model in Vivo: A Comparison Between MRI and Small Animal CT

    Energy Technology Data Exchange (ETDEWEB)

    Wang, B; He, W; Cvetkovic, D; Chen, L; Fan, J; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States)

    2016-06-15

    Purpose: The purpose of the study is to compare the volume measurement of subcutaneous tumors in mice with different imaging platforms, namely a GE MRI and a Sofie-Biosciences small animal CT scanner. Methods: A549 human lung carcinoma cells and FaDu human head and neck squamous cell carcinoma cells were implanted subcutaneously into flanks of nude mice. Three FaDu tumors and three A549 tumors were included in this study. The MRI scans were done with a GE Signa 1.5 Tesla MR scanner using a fast T2-weighted sequence (70mm FOV and 1.2mm slice thickness), while the CT scans were done with the CT scanner on a Sofie-Biosciences G8 PET/CT platform dedicated for small animal studies (48mm FOV and 0.2mm slice thickness). Imaging contrast agent was not used in this study. Based on the DICOM images from MRI and CT scans, the tumors were contoured with Philips DICOM Viewer and the tumor volumes were obtained by summing up the contoured area and multiplied by the slice thickness. Results: The volume measurements based on the CT scans agree reasonably with that obtained with MR images for the subcutaneous tumors. The mean difference in the absolute tumor volumes between MRI- and CT-based measurements was found to be −6.2% ± 1.0%, with the difference defined as (VMR – VCT)*100%/VMR. Furthermore, we evaluated the normalized tumor volumes, which were defined for each tumor as V/V{sub 0} where V{sub 0} stands for the volume from the first MR or CT scan. The mean difference in the normalized tumor volumes was found to be 0.10% ± 0.96%. Conclusion: Despite the fact that the difference between normal and abnormal tissues is often less clear on small animal CT images than on MR images, one can still obtain reasonable tumor volume information with the small animal CT scans for subcutaneous murine xenograft models.

  2. Enabling image fusion for a CT guided needle placement robot

    Science.gov (United States)

    Seifabadi, Reza; Xu, Sheng; Aalamifar, Fereshteh; Velusamy, Gnanasekar; Puhazhendi, Kaliyappan; Wood, Bradford J.

    2017-03-01

    Purpose: This study presents development and integration of hardware and software that enables ultrasound (US) and computer tomography (CT) fusion for a FDA-approved CT-guided needle placement robot. Having real-time US image registered to a priori-taken intraoperative CT image provides more anatomic information during needle insertion, in order to target hard-to-see lesions or avoid critical structures invisible to CT, track target motion, and to better monitor ablation treatment zone in relation to the tumor location. Method: A passive encoded mechanical arm is developed for the robot in order to hold and track an abdominal US transducer. This 4 degrees of freedom (DOF) arm is designed to attach to the robot end-effector. The arm is locked by default and is released by a press of button. The arm is designed such that the needle is always in plane with US image. The articulated arm is calibrated to improve its accuracy. Custom designed software (OncoNav, NIH) was developed to fuse real-time US image to a priori-taken CT. Results: The accuracy of the end effector before and after passive arm calibration was 7.07mm +/- 4.14mm and 1.74mm +/-1.60mm, respectively. The accuracy of the US image to the arm calibration was 5mm. The feasibility of US-CT fusion using the proposed hardware and software was demonstrated in an abdominal commercial phantom. Conclusions: Calibration significantly improved the accuracy of the arm in US image tracking. Fusion of US to CT using the proposed hardware and software was feasible.

  3. CT features of the subtypes of thymic epithelial tumors on the basis of the world health organization classification

    International Nuclear Information System (INIS)

    Guo Xiaoyu; Yu Hong; Xiao Xiangsheng

    2013-01-01

    Thymic epithelial tumors including thymomas and thymic carcinomas have well-known heterogeneous oncologic behaviors and variable histologic features. They show variable and unpredictable evolutions ranging from an indolent non-invasive feature to a highly infiltrative and metastasising one. Currently, CT is a common and efficient imaging method for assessing thymic epithelial tumors. CT evaluation is the main reference for preoperative clinic staging and histological classification. CT features of subtypes of thymic epithelial tumors on the basis of the World Health Organization classification provide the foundation for the diagnosis and predicting prognosis. (authors)

  4. Quantifying the impact of respiratory-gated 4D CT acquisition on thoracic image quality : a digital phantom study

    NARCIS (Netherlands)

    Bernatowicz, K; Keall, P; Mishra, P; Knopf, A; Lomax, A; Kipritidis, J

    PURPOSE: Prospective respiratory-gated 4D CT has been shown to reduce tumor image artifacts by up to 50% compared to conventional 4D CT. However, to date no studies have quantified the impact of gated 4D CT on normal lung tissue imaging, which is important in performing dose calculations based on

  5. Improvement of internal tumor volumes of non-small cell lung cancer patients for radiation treatment planning using interpolated average CT in PET/CT.

    Directory of Open Access Journals (Sweden)

    Yao-Ching Wang

    Full Text Available Respiratory motion causes uncertainties in tumor edges on either computed tomography (CT or positron emission tomography (PET images and causes misalignment when registering PET and CT images. This phenomenon may cause radiation oncologists to delineate tumor volume inaccurately in radiotherapy treatment planning. The purpose of this study was to analyze radiology applications using interpolated average CT (IACT as attenuation correction (AC to diminish the occurrence of this scenario. Thirteen non-small cell lung cancer patients were recruited for the present comparison study. Each patient had full-inspiration, full-expiration CT images and free breathing PET images by an integrated PET/CT scan. IACT for AC in PET(IACT was used to reduce the PET/CT misalignment. The standardized uptake value (SUV correction with a low radiation dose was applied, and its tumor volume delineation was compared to those from HCT/PET(HCT. The misalignment between the PET(IACT and IACT was reduced when compared to the difference between PET(HCT and HCT. The range of tumor motion was from 4 to 17 mm in the patient cohort. For HCT and PET(HCT, correction was from 72% to 91%, while for IACT and PET(IACT, correction was from 73% to 93% (*p<0.0001. The maximum and minimum differences in SUVmax were 0.18% and 27.27% for PET(HCT and PET(IACT, respectively. The largest percentage differences in the tumor volumes between HCT/PET and IACT/PET were observed in tumors located in the lowest lobe of the lung. Internal tumor volume defined by functional information using IACT/PET(IACT fusion images for lung cancer would reduce the inaccuracy of tumor delineation in radiation therapy planning.

  6. Diagnosis of ovarian tumors by ultrasonography and x-ray CT

    International Nuclear Information System (INIS)

    Watanabe, Hiromu

    1986-01-01

    A drawback in ultrasonography, an indispensable technique in imaging ovarian malignancies, is that it sometimes shows false positive for benign tumors including dermoid cyst and ovarian endometriosis. To overcome this, the concurrent use of X-Ray CT seems warrantable and this led us to carry out the study summarized below. CT was carried out on 268 of 322 ovarian disease cases which had undergone ultrasonography. The results obtained were as follows. Sensitivity of ultrasonography and CT in ovarian malignancies were 82 % and 88 % respectively. Of the cases subjected to both techniques, those who were deemed false positive were 39 in ultrasonography and 12 in CT. Ultrasonographic imagings of dermoid cyst and ovarian endometriosis were classified on the basis of their patterns. The results obtained revealed that those in which it was difficult to discriminate the image from ovarian malignancy were types V and VI in dermoid cyst and type III-C in ovarian endometriosis. In both dermoid cyst and ovarian endometriosis, nearly a 100 % accuracy rate was obtainable with CT for diagnosis of benign tumors. This strongly suggested that concurrent use of CT was required, in diagnosing ovarian diseases with the V or VI and III-C patterns referred to above. (author)

  7. Vascular imaging with spiral CT. The way to CY angiography

    International Nuclear Information System (INIS)

    Prokop, M.; Schaefer, C.; Kalender, W.A.; Polacin, A.; Galanski, M.

    1993-01-01

    Spiral CT is a technique that allows for high-quality two-dimensional angiographic projections and 3D imaging of vascular structures. The authors present the technical and methodological principles of the technique, including scan parameters and parameters of contrast application for various clinical imaging tasks. They present their experience with over 150 clinical cases using spiral CT angiography. Suitable applications of this technique include cogenital anomalies, aneurysms, dissections, stenoses, thrombi and vascular tumor involvement. Given a problem-adapted examination technique, pathologic changes in vessels of as little as 2 mm can be visualized. In some cases with complex vascular anatomy, spiral CT angiography can be superior to arterial angiography. (orig.) [de

  8. Correlation of intra-tumor 18F-FDG uptake heterogeneity indices with perfusion CT derived parameters in colorectal cancer.

    Science.gov (United States)

    Tixier, Florent; Groves, Ashley M; Goh, Vicky; Hatt, Mathieu; Ingrand, Pierre; Le Rest, Catherine Cheze; Visvikis, Dimitris

    2014-01-01

    Thirty patients with proven colorectal cancer prospectively underwent integrated 18F-FDG PET/DCE-CT to assess the metabolic-flow phenotype. Both CT blood flow parametric maps and PET images were analyzed. Correlations between PET heterogeneity and perfusion CT were assessed by Spearman's rank correlation analysis. Blood flow visualization provided by DCE-CT images was significantly correlated with 18F-FDG PET metabolically active tumor volume as well as with uptake heterogeneity for patients with stage III/IV tumors (|ρ|:0.66 to 0.78; p-valueheterogeneity of 18F-FDG PET accumulation reflects to some extent tracer distribution and consequently indicates that 18F-FDG PET intra-tumor heterogeneity may be associated with physiological processes such as tumor vascularization.

  9. Solitary Fibrous Tumor of the Pancreas: Imaging Findings

    International Nuclear Information System (INIS)

    Kwon, Heon Ju; Byun, Jae Ho; Kang, Jun; Park, Seong Ho; Lee, Moon Gyu

    2008-01-01

    We report here a case of a pathologically proven solitary fibrous tumor of the pancreas. A 54-year-old man was referred to our hospital for further evaluation of a pancreatic mass that was found incidentally. CT, MR imaging, and endoscopic ultrasonography showed a well-defined, enhancing mass with cystic portions of the pancreas body. MR cholangiopancreatography showed no pancreatic duct dilatation. A solitary fibrous tumor of the pancreas is a very rare lesion

  10. Modified CT imaging by reduction factor transformations

    International Nuclear Information System (INIS)

    Doehring, W.; Linke, G.

    1981-01-01

    The possibilities of CT image modification which had existed so far for given matrix of attenuation values (window setting, highlighting, black-and-white or colour reversal and logarithmic distortion of the video signal) are supplemented by the method of attenuation value transformation. As a specific case a linear interval by interval attenuation value transformation is described. First of all, the intirety of the measured CT values is transformed into the corresponding CT quotients (CTQ) and then subdivided into 5 optional intervals. Each one freely selected CTQ value can be allocated to the first and to the last interval; the intermediate 3 intervals can be linearly transformed at random. The article discusses the influence of such a manipulation on CT image reproduction; this is of particular importance for the image visualisation of the results of quantitative organ analyses by means of computed tomography. The presented paper also points to the possibility of effecting further attenuation value transformations. (orig.) [de

  11. A case of primary neuroendcrine tumor of liver with FDG accumulation by PET/CT

    International Nuclear Information System (INIS)

    Okumura, Yoshihiro; Kishi, Ryotaro; Uka, Mayu; Tsuchihashi, Kazuyo; Hyodo, Takeshi; Takakura, Norihisa; Iguchi, Toshihiro; Kanazawa, Susumu

    2014-01-01

    We report an 80's male with primary hepatic neuroendcrine tumor without clinical symptom. dynamic contrast CT showed a hypervascular tumor at S5 of the liver. EOB-MRI showed high intensity on T2WI, low intensity on T1WI, the hepatic phase and the diffusion weighted image. It showed high FDG accumulation. Pathological examination confirmed neuroendcrine tumor of liver, G2 stage, and owing to the CD56 positive, 12.6% at MIB-1 index, with a little necrosis, no capsule and hemorrhage. (author)

  12. CT analysis of intratumoral gas formation after hepatic tumor embolization

    International Nuclear Information System (INIS)

    Kim, Hyun Sook; Ahn, In Oak; Kim, Hyung Jin; Lee, Goo; Chung, Sung Hoon

    1994-01-01

    To evaluate the prevalence and the patterns of sterile gas shown at computed tomography(CT) after transarterial embolization(TAE) for primary hepatic tumor. Among 102 patients who performed TAE for hepatoma, thirty-four in whom follow-up CT was underwent constituted the basis of our study. At CT, we evaluated the patterns and locations of intratumoral gas. We also reviewed the clinical data to exclude an infectious origin of intratumoral gas. Of 34 patients, intratumoral gas was detected in 11 patients(32%), in all of whom Gelfoam was used as an embolic material. The initial tumor size measured at pre-TAE CT was larger in patients with intratumoral gas than in patients without it(p < 0.005). No specific patterns or locations of intratumoral gas were noted on CT scans. No patients had clinical signs and symptoms that suggested infection. Intratumoral gas formation without clinical evidence of infection is not an infrequent finding after TAE for hepatoma, especially when Gelfoam is used and when the tumor is larger in size. This finding may be a part of postinfarction syndrome and should not be misinterpreted as an postprocedural abscess formation

  13. Non-tumor enhancement at the surgical margin on CT after the removal of brain tumors

    International Nuclear Information System (INIS)

    Adachi, Michito; Hosoya, Takaaki; Yamaguchi, Kohichi; Yamada, Kiyotada

    1992-01-01

    Marginal enhancement is occasionally seen at the surgical margin on CT after the total removal of brain tumors. This enhancement disappears in due time, and therefore we call it non-tumor enhancement. It is often difficult, however, to differentiate non-tumor enhancement from tumor recurrence. In this study, we attempted to determine the characteristics of non-tumor enhancement. The subjects of the study consisted of 15 patients with astrocytoma and one with metastatic tumor in whom sequential CT scans had been performed after total removal of the tumor. Based on the observation of these sequential CT scans, the characteristics of non-tumor enhancement were presumed to be as follows: (1) In four cases, enhancement at the surgical margin persisted more than four months after surgery and then disappeared. Therefore, these cases were considered non-tumor enhancement. Prolonged duration of enhancement such as that in these cases is not necessarily due to recurrence. Marginal enhancement within 3 mm in thickness and with a well-demarcated border like that of a flax is likely to be non-tumor enhancement. (author)

  14. Accuracy verification of PET-CT image fusion and its utilization in target delineation of radiotherapy

    International Nuclear Information System (INIS)

    Wang Xuetao; Yu Jinming; Yang Guoren; Gong Heyi

    2005-01-01

    Objective: Evaluate the accuracy of co-registration of PET and CT (PET-CT) images on line with phantom, and utilize it on patients to provide clinical evidence for target delineation in radiotherapy. Methods: A phantom with markers and different volume cylinders was infused with various concentrations of 18 FDG, and scanned at 4 mm by PET and CT respectively. After having been transmitted into GE eNTEGRA and treatment planning system (TPS) workstations, the images were fused and reconstructed. The distance between the markers and the errors were monitored in PET and CT images respectively. The volume of cylinder in PET and CT images were measured and compared by certain pixel value proportion deduction method. The same procedure was performed on the pulmonary tumor image in ten patients. Results: eNTEGRA and TPS workstations had a good length linearity, but the fusion error of the latter was markedly greater than the former. Tumors in different volume filled by varying concentrations of 18 FDG required different pixel deduction proportion. The cylinder volume of PET and CT images were almost the same, so were the images of pulmonary tumor of ten patients. Conclusions: The accuracy of image co-registration of PET-CT on line may fulfill the clinical demand. Pixel value proportion deduction method can be used for target delineation on PET image. (authors)

  15. New developments in imaging: Sonography, cine-CT, MRI

    International Nuclear Information System (INIS)

    Otto, R.J.; Higgins, C.B.

    1987-01-01

    The book can be conveniently subdivided into three sections: the first on magnetic resonance imaging the second on cine-computed tomography and the third on advances in ultrasound (US). The MR imaging section includes two chapters: the first on indications for MR in abdominal disease (a cookbook layout of indications for MR imaging versus CT) and the second on MR imaging of the heart. There are also chapters on MR imaging and US in the pelvis, contrast agent principles, and a chapter on imaging renal tumors. The third section, on US, contains chapters on the liver and gastrointenstinal disease, interventional US sonography during neurosurgery, state-of-the-art echocardiography. Doppler flow imaging, contrast media for sonography, endometrial sonography, and high-resolution US in the first trimester. The final chapter is presented as a scientific paper rather than as a chapter in a book and has no illustrations

  16. Craniopharyngioma identification by CT and MR imaging at 1.5 T

    Energy Technology Data Exchange (ETDEWEB)

    Hald, J.K. [Dept. of Radiology, Rikshospitalet, Oslo Univ. (Norway)]|[Dept. of Radiology, Univ. of Michigan Hospitals, Ann Arbor, MI (United States); Eldevik, O.P. [Dept. of Radiology, Rikshospitalet, Oslo Univ. (Norway)]|[Dept. of Radiology, Univ. of Michigan Hospitals, Ann Arbor, MI (United States); Skalpe, I.O. [Dept. of Radiology, Rikshospitalet, Oslo Univ. (Norway)]|[Dept. of Radiology, Univ. of Michigan Hospitals, Ann Arbor, MI (United States)

    1995-03-01

    To compare the detectability of craniopharyngiomas by CT and MR imaging, preoperative CT and MR studies obtained within 16 days of each other were evaluated retrospectively in 9 patients. MR imaging demonstrated cystic and solid tumor components in all 9 tumors, and enhancement in the 7 tumors that were studied after contrast medium injection. MR imaging demonstrated a signal void consistent with calcification in 4 patients. Combining unenhanced and contrast medium-enhanced studies, CT also identified all the tumors. CT demonstrated cysts in 7 lesions, calcification in 7 and enhancement in 6 of the 7 lesions that received i.v. contrast medium. Calcification was better seen by CT than MR imaging, while MR imaging identified cystic tumor components not seen on CT. The contrast medium enhancement pattern was the same with the 2 modalities. MR imaging of the sellar region, including at least one contrast medium-enhanced sequence, should be sufficient in most instances to establish a preoperative diagnosis of craniopharyngioma. (orig.).

  17. Improving image quality in portal venography with spectral CT imaging

    International Nuclear Information System (INIS)

    Zhao, Li-qin; He, Wen; Li, Jian-ying; Chen, Jiang-hong; Wang, Ke-yang; Tan, Li

    2012-01-01

    Objective: To investigate the effect of energy spectral CT on the image quality of CT portal venography in cirrhosis patients. Materials and methods: 30 portal hypertension patients underwent spectral CT examination using a single-tube, fast dual tube voltage switching technique. 101 sets of monochromatic images were generated from 40 keV to 140 keV. Image noise and contrast-to-noise ratio (CNR) for portal veins from the monochromatic images were measured. An optimal monochromatic image set was selected for obtaining the best CNR for portal veins. The image noise and CNR of the intra-hepatic portal vein and extra-hepatic main stem at the selected monochromatic level were compared with those from the conventional polychromatic images. Image quality was also assessed and compared. Results: The monochromatic images at 51 keV were found to provide the best CNR for both the intra-hepatic and extra-hepatic portal veins. At this energy level, the monochromatic images had about 100% higher CNR than the polychromatic images with a moderate 30% noise increase. The qualitative image quality assessment was also statistically higher with monochromatic images at 51 keV. Conclusion: Monochromatic images at 51 keV for CT portal venography could improve CNR for displaying hepatic portal veins and improve the overall image quality.

  18. Improving image quality in portal venography with spectral CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Li-qin, E-mail: zhaolqzr@sohu.com [Department of Radiology, Beijing Friendship Hospital Affiliated to Capital Medical University, Beijing,100050 (China); He, Wen, E-mail: hewen1724@sina.com [Department of Radiology, Beijing Friendship Hospital Affiliated to Capital Medical University, Beijing,100050 (China); Li, Jian-ying, E-mail: jianying.li@med.ge.com [CT Advanced Application and Research, GE Healthcare, 100176 China (China); Chen, Jiang-hong, E-mail: chenjianghong1973@hotmail.com [Department of Radiology, Beijing Friendship Hospital Affiliated to Capital Medical University, Beijing,100050 (China); Wang, Ke-yang, E-mail: ke7ke@sina.com [Department of Radiology, Beijing Friendship Hospital Affiliated to Capital Medical University, Beijing,100050 (China); Tan, Li, E-mail: Litan@ge.com [CT product, GE Healthcare, 100176 China (China)

    2012-08-15

    Objective: To investigate the effect of energy spectral CT on the image quality of CT portal venography in cirrhosis patients. Materials and methods: 30 portal hypertension patients underwent spectral CT examination using a single-tube, fast dual tube voltage switching technique. 101 sets of monochromatic images were generated from 40 keV to 140 keV. Image noise and contrast-to-noise ratio (CNR) for portal veins from the monochromatic images were measured. An optimal monochromatic image set was selected for obtaining the best CNR for portal veins. The image noise and CNR of the intra-hepatic portal vein and extra-hepatic main stem at the selected monochromatic level were compared with those from the conventional polychromatic images. Image quality was also assessed and compared. Results: The monochromatic images at 51 keV were found to provide the best CNR for both the intra-hepatic and extra-hepatic portal veins. At this energy level, the monochromatic images had about 100% higher CNR than the polychromatic images with a moderate 30% noise increase. The qualitative image quality assessment was also statistically higher with monochromatic images at 51 keV. Conclusion: Monochromatic images at 51 keV for CT portal venography could improve CNR for displaying hepatic portal veins and improve the overall image quality.

  19. Advances in CT imaging for urolithiasis

    Directory of Open Access Journals (Sweden)

    Yasir Andrabi

    2015-01-01

    Full Text Available Urolithiasis is a common disease with increasing prevalence worldwide and a lifetime-estimated recurrence risk of over 50%. Imaging plays a critical role in the initial diagnosis, follow-up and urological management of urinary tract stone disease. Unenhanced helical computed tomography (CT is highly sensitive (>95% and specific (>96% in the diagnosis of urolithiasis and is the imaging investigation of choice for the initial assessment of patients with suspected urolithiasis. The emergence of multi-detector CT (MDCT and technological innovations in CT such as dual-energy CT (DECT has widened the scope of MDCT in the stone disease management from initial diagnosis to encompass treatment planning and monitoring of treatment success. DECT has been shown to enhance pre-treatment characterization of stone composition in comparison with conventional MDCT and is being increasingly used. Although CT-related radiation dose exposure remains a valid concern, the use of low-dose MDCT protocols and integration of newer iterative reconstruction algorithms into routine CT practice has resulted in a substantial decrease in ionizing radiation exposure. In this review article, our intent is to discuss the role of MDCT in the diagnosis and post-treatment evaluation of urolithiasis and review the impact of emerging CT technologies such as dual energy in clinical practice.

  20. Differentiation of large (≥5 cm) gastrointestinal stromal tumors from benign subepithelial tumors in the stomach: Radiologists’ performance using CT

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Ye Ra [Department of Radiology, Seoul National University Hospital (Korea, Republic of); Kim, Se Hyung, E-mail: shkim7071@gmail.com [Department of Radiology, Seoul National University Hospital (Korea, Republic of); The Institute of Radiation Medicine, Seoul National University Hospital (Korea, Republic of); Kim, Sun-Ah [Department of Radiology, Seoul National University Hospital (Korea, Republic of); Shin, Cheong-il [Department of Radiology, Seoul National University Hospital (Korea, Republic of); The Institute of Radiation Medicine, Seoul National University Hospital (Korea, Republic of); Kim, Hyung Jin; Kim, Seong Ho [Department of Radiology, Seoul National University Hospital (Korea, Republic of); Han, Joon Koo; Choi, Byung Ihn [Department of Radiology, Seoul National University Hospital (Korea, Republic of); The Institute of Radiation Medicine, Seoul National University Hospital (Korea, Republic of)

    2014-02-15

    Purpose: To identify significant CT findings for the differentiation of large (≥5 cm) gastric gastrointestinal stromal tumors (GIST) from benign subepithelial tumors and to assess whether radiologists’ performance in differentiation is improved with knowledge of significant CT criteria. Materials and methods: One-hundred twenty patients with pathologically proven large (≥5 cm) GISTs (n = 99), schwannomas (n = 16), and leiomyomas (n = 5) who underwent CT were enrolled. Two radiologists (A and B) retrospectively reviewed their CT images in consensus for the location, size, degree and pattern of enhancement, contour, growth pattern and the presence of calcification, necrosis, surface ulceration, or enlarged lymph nodes. CT findings considered significant for differentiation were determined using uni- and multivariate statistical analyses. Thereafter, two successive review sessions for the differentiation of GIST from non-GIST were independently performed by two other reviewers (C and D) with different expertise of 2 and 9 years using a 5-point confidence scale. At the first session, reviewers interpreted CT images without knowledge of significant CT findings. At the second session, the results of statistical analyses were provided to the reviewers. To assess improvement in radiologists’ performance, a pairwise comparison of receiver operating curves (ROC) was performed. Results: Heterogeneous enhancement, presence of necrosis, absence of lymph nodes, and mean size of ≥6 cm were found to be significant for differentiating GIST from schwannoma (P < 0.05). Non-cardial location, heterogeneous enhancement, and presence of necrosis were differential CT features of GIST from leiomyoma (P < 0.05). Multivariate analyses indicated that absence of enlarged LNs was the only statistically significant variable for GIST differentiating from schwannoma. The area under the curve of both reviewers obtained using ROC significantly increased from 0.682 and 0.613 to 0.903 and 0

  1. Research of ART method in CT image reconstruction

    International Nuclear Information System (INIS)

    Li Zhipeng; Cong Peng; Wu Haifeng

    2005-01-01

    This paper studied Algebraic Reconstruction Technique (ART) in CT image reconstruction. Discussed the ray number influence on image quality. And the adopting of smooth method got high quality CT image. (authors)

  2. Computed tomography of liver tumors, 2. Differential diagnosis between hepatocellular carcinoma and metastatic hepatic tumor by dynamic CT scanning

    Energy Technology Data Exchange (ETDEWEB)

    Naito, Akira; Fukuoka, Haruhito; Kashiwado, Kouzou; Ichiki, Toshio; Makidono, Yoko [Hiroshima Red Cross Hospital (Japan)

    1984-02-01

    Differential diagnosis between hepatocellular carcinoma and metastatic hepatic tumor was attempted using dynamic CT scanning. Homogeneous and patchy types were peculiar to hepatocellular carcinoma, and ring-like type to metastatic hepatic tumor. However, with no enhancement, hepatocellular carcinoma could not be denied. Hepatocellular carcinoma was characterized by the enhancement shown on the early stage of dynamic CT. Ring enhancement was not visualized on dynamic CT but visualized on conventional contrast enhanced CT in hepatocellular carcinomas; it was visualized on conventional contrast enhanced CT and on dynamic CT in metastatic hepatic tumors.

  3. Benign fatty tumors: classification, clinical course, imaging appearance, and treatment

    International Nuclear Information System (INIS)

    Bancroft, Laura W.; Kransdorf, Mark J.; Peterson, Jeffrey J.; O'Connor, Mary I.

    2006-01-01

    Lipoma is the most common soft-tissue tumor, with a wide spectrum of clinical presentations and imaging appearances. Several subtypes are described, ranging from lesions entirely composed of mature adipose tissue to tumors intimately associated with nonadipose tissue, to those composed of brown fat. The imaging appearance of these fatty masses is frequently sufficiently characteristic to allow a specific diagnosis. However, in other cases, although a specific diagnosis is not achievable, a meaningful limited differential diagnosis can be established. The purpose of this manuscript is to review the spectrum of benign fatty tumors highlighting the current classification system, clinical presentation and behavior, spectrum of imaging appearances, and treatment. The imaging review emphasizes computed tomography (CT) scanning and magnetic resonance (MR) imaging, differentiating radiologic features. (orig.)

  4. Pathologic contrast enhancement of cerebral lesions: A comparative study using stereotactic CT, stereotactic MR imaging, and stereotactic biopsy

    International Nuclear Information System (INIS)

    Earnest, F. IV; Kelly, P.J.; Scheithauer, B.; Kall, B.; Cascino, T.L.; Ehman, R.L.; Forbes, G.

    1986-01-01

    The author compared the pattern and degree of Gd-DTPA dimeglumine contrast enhancement demonstrated on stereotactic MR images with that seen on stereotactic CT images obtained after conventional iodinated contrast agent enhancement and with histopathologic findings on sequential stereotactic brain biopsies. Stereotactic biopsies of the areas that enhanced on CT or MR imaging revealed tumor tissue with neovascularity. Tumor tissue with no or mild neovascularity did not enhance with contrast agent administration. Isolated tumor cells were frequently found beyond the margins of some primary brain neoplasms defined by contrast agent-enhanced MR imaging and CT. The histopathologic findings associated with pathologic contrast agent enhancement are presented

  5. CT image registration in sinogram space.

    Science.gov (United States)

    Mao, Weihua; Li, Tianfang; Wink, Nicole; Xing, Lei

    2007-09-01

    Object displacement in a CT scan is generally reflected in CT projection data or sinogram. In this work, the direct relationship between object motion and the change of CT projection data (sinogram) is investigated and this knowledge is applied to create a novel algorithm for sinogram registration. Calculated and experimental results demonstrate that the registration technique works well for registering rigid 2D or 3D motion in parallel and fan beam samplings. Problem and solution for 3D sinogram-based registration of metallic fiducials are also addressed. Since the motion is registered before image reconstruction, the presented algorithm is particularly useful when registering images with metal or truncation artifacts. In addition, this algorithm is valuable for dealing with situations where only limited projection data are available, making it appealing for various applications in image guided radiation therapy.

  6. CT image registration in sinogram space

    International Nuclear Information System (INIS)

    Mao Weihua; Li Tianfang; Wink, Nicole; Xing Lei

    2007-01-01

    Object displacement in a CT scan is generally reflected in CT projection data or sinogram. In this work, the direct relationship between object motion and the change of CT projection data (sinogram) is investigated and this knowledge is applied to create a novel algorithm for sinogram registration. Calculated and experimental results demonstrate that the registration technique works well for registering rigid 2D or 3D motion in parallel and fan beam samplings. Problem and solution for 3D sinogram-based registration of metallic fiducials are also addressed. Since the motion is registered before image reconstruction, the presented algorithm is particularly useful when registering images with metal or truncation artifacts. In addition, this algorithm is valuable for dealing with situations where only limited projection data are available, making it appealing for various applications in image guided radiation therapy

  7. Ga-68-DOTA-TATE PET/CT for discrimination of tumors of the optic pathway.

    Science.gov (United States)

    Klingenstein, Annemarie; Haug, Alexander R; Miller, Christina; Hintschich, Christoph

    2015-02-01

    Symptomatic tumors of the optic nerve pathway may endanger vision. They are difficult to classify by imaging alone and biopsy may damage visual function. Tumor pathology influences treatment decision and a diagnostic tool with a high sensitivity and specificity would therefore be invaluable. We hypothesized that Ga-68-DOTA-TATE PET/CT may help in discriminating optic nerve tumors as uptake of somatostatin is elevated in meningiomas. Ga-68-DOTA-TATE PET/CT was used to examine 13 patients with ambiguous, symptomatic lesions of the optic pathway for treatment planning. The presence or absence of meningioma was validated by histopathology or supplementary diagnostic work-up. Ga-68-DOTA-TATE PET/CT identified 10 meningiomas (en plaque = 1, optic nerve sheath = 4, sphenoidal = 5) correctly via increased SSTR (somatostatin receptor) expression (mean SUVmax (maximum standardized uptake value) = 14.3 ± 15.4). 3 tumors did not show elevated Ga-68-DOTA-TATE uptake (SUVmax = 2.1 ± 1.0). Subsumizing all clinical-radiological follow-up tools available, these lesions were classified as an intracerebral metastasis of an advanced gastric carcinoma, histologically proven inflammatory collagenous connective tissue and presumed leukemic infiltration of a newly diagnosed chronic lymphocytic leukemia. In this case series, Ga-68-DOTA-TATE PET/CT demonstrated both a sensitivity and specificity of 100%. Yet, the golden standard of histopathology was only available in a subset of patients included. Ga-68-DOTA-TATE PET/CT proved to be a valuable diagnostic tool for the correct classification of equivocal, symptomatic tumors of the anterior optic pathway requiring therapy. PET/CT results influenced therapy decision essentially in all cases.

  8. Dose performance and image quality: Dual source CT versus single source CT in cardiac CT angiography

    International Nuclear Information System (INIS)

    Wang Min; Qi Hengtao; Wang Ximing; Wang Tao; Chen, Jiu-Hong; Liu Cheng

    2009-01-01

    Objective: To evaluate dose performance and image quality of 64-slice dual source CT (DSCT) in comparison to 64-slice single source CT (SSCT) in cardiac CT angiography (CTA). Methods: 100 patients examined by DSCT and 60 patients scanned by SSCT were included in this study. Objective indices such as image noise, contrast-to-noise ratio and signal-to-noise ratio were analyzed. Subjective image quality was assessed by two cardiovascular radiologists in consensus using a four-point scale (1 = excellent to 4 = not acceptable). Estimation of effective dose was performed on the basis of dose length product (DLP). Results: At low heart rates ( 0.05), but, at high heart rates (>70 bpm), DSCT provided robust image quality (P 70 bpm), DSCT is able to provide robust diagnostic image quality at doses far below that of SSCT.

  9. Multislice CT imaging of pulmonary embolism

    International Nuclear Information System (INIS)

    Schoepf, J.U.; Kessler, M.A.; Rieger, C.T.; Herzog, P.; Wiesgigl, S.; Becker, C.R.; Exarhos, D.N.; Reiser, M.F.

    2001-01-01

    In recent years CT has been established as the method of choice for the diagnosis of central pulmonary embolism (PE) to the level of the segmental arteries. The key advantage of CT over competing modalities is the reliable detection of relevant alternative or additional disease causing the patient's symptoms. Although the clinical relevance of isolated peripheral emboli remains unclear, the alleged poor sensitivity of CT for the detection of such small clots has to date prevented the acceptance of CT as the gold standard for diagnosing PE. With the advent of multislice CT we can now cover the entire chest of a patient with 1-mm slices within one breath-hold. In comparison with thicker sections, the detection rate of subsegmental emboli can be significantly increased with 1-mm slices. In addition, the interobserver correlation which can be achieved with 1-mm sections by far exceeds the reproducibility of competing modalities. Meanwhile use of multislice CT for a combined diagnosis of PE and deep venous thrombosis with the same modality appears to be clinically accepted. In the vast majority of patients who receive a combined thoracic and venous multislice CT examination the scan either confirms the suspected diagnosis or reveals relevant alternative or additional disease. The therapeutic regimen is usually chosen based on the functional effect of embolic vascular occlusion. With the advent of fast CT scanning techniques, also functional parameters of lung perfusion can be non-invasively assessed by CT imaging. These advantages let multislice CT appear as an attractive modality for a non-invasive, fast, accurate, and comprehensive diagnosis of PE, its causes, effects, and differential diagnoses. (orig.)

  10. Blind CT image quality assessment via deep learning strategy: initial study

    Science.gov (United States)

    Li, Sui; He, Ji; Wang, Yongbo; Liao, Yuting; Zeng, Dong; Bian, Zhaoying; Ma, Jianhua

    2018-03-01

    Computed Tomography (CT) is one of the most important medical imaging modality. CT images can be used to assist in the detection and diagnosis of lesions and to facilitate follow-up treatment. However, CT images are vulnerable to noise. Actually, there are two major source intrinsically causing the CT data noise, i.e., the X-ray photo statistics and the electronic noise background. Therefore, it is necessary to doing image quality assessment (IQA) in CT imaging before diagnosis and treatment. Most of existing CT images IQA methods are based on human observer study. However, these methods are impractical in clinical for their complex and time-consuming. In this paper, we presented a blind CT image quality assessment via deep learning strategy. A database of 1500 CT images is constructed, containing 300 high-quality images and 1200 corresponding noisy images. Specifically, the high-quality images were used to simulate the corresponding noisy images at four different doses. Then, the images are scored by the experienced radiologists by the following attributes: image noise, artifacts, edge and structure, overall image quality, and tumor size and boundary estimation with five-point scale. We trained a network for learning the non-liner map from CT images to subjective evaluation scores. Then, we load the pre-trained model to yield predicted score from the test image. To demonstrate the performance of the deep learning network in IQA, correlation coefficients: Pearson Linear Correlation Coefficient (PLCC) and Spearman Rank Order Correlation Coefficient (SROCC) are utilized. And the experimental result demonstrate that the presented deep learning based IQA strategy can be used in the CT image quality assessment.

  11. Interobserver and Intraobserver Variability among Measurements of FDG PET/CT Parameters in Pulmonary Tumors

    Directory of Open Access Journals (Sweden)

    Gülgün Büyükdereli

    2016-06-01

    Full Text Available Background: 18F-fluorodeoxyglucose (FDG positron emission tomography computed tomography (PET/CT provides information about metabolic and morphologic status of malignancies. Tumor size and standardized uptake value (SUV measurements are crucial for cancer treatment monitoring.: 18F-fluorodeoxyglucose (FDG positron emission tomography computed tomography (PET/CT provides information about metabolic and morphologic status of malignancies. Tumor size and standardized uptake value (SUV measurements are crucial for cancer treatment monitoring. Aims: The purpose of our study was to assess the variability of these measurements performed by observers evaluating lung tumors. Study Design: Retrospective cross-sectional study. Methods: FDG PET/CT images of 97 patients with pulmonary tumors were independently evaluated by two experienced nuclear medicine physicians. Primary tumor size (UDCT, maximum SUV (SUVmax, mean SUV (SUVmean and maximum SUV normalized to liver mean SUV (SUVnliv max were measured by each observer at two different times with an interval of at least 2 weeks. Interobserver and intraobserver variabilities of measurements were evaluated through statistical methods. Results: Size of the lesions varied from 0.81 to 13.6 cm (mean 4.29±2.24 cm. Very good agreement was shown with correlation, Bland-Altman and regression analysis for all measured PET/CT parameters. In the interobserver and intraobserver variability analysis, the Pearson correlation coefficients were greater than 0.96 and 0.98, respectively. Conclusion: Semi-quantitative measurements of pulmonary tumors were highly reproducible when determined by experienced physicians with clinically available software for routine FDG PET/CT evaluation. Consistency may be improved if the same observer performs serial measurements for any one patient.

  12. Imaging features of intracranial solitary fibrous tumors

    International Nuclear Information System (INIS)

    Yu Shuilian; Man Yuping; Ma Longbai; Liu Ying; Wei Qiang; Zhu Youkai

    2012-01-01

    Objective: To summarize the imaging features of intracranial solitary fibrous tumors (ISFT). Methods: Ten patients with ISFT proven histopathologically were collected. Four cases had CT data and all cases had MR data. The imaging features and pathological results were retrospectively analyzed. Results: All cases were misdiagnosed as meningioma at pre-operation. All lesions arose from intracranial meninges including 5 lesions above the tentorium, 4 lesions beneath the tentorium and 1 lesion growing around the tentorium. The margins of all the masses were well defined, and 8 lesions presented multilobular shape. CT demonstrated hyerattenuated masses in all 4 lesions, smooth erosion of the basicranial skull in 1 lesion, and punctiform calcification of the capsule in 1 lesion. T 1 WI showed most lesions with isointense or slight hyperintense signals including homogeneous in 4 lesions and heterogeneous in 6 lesions. T 2 WI demonstrated isointense or slight hyperintense in 2 lesions, mixed hypointense and hyperintense signals in 4, cystic portion in 2, and two distinct portion of hyperintense and hypointense signal, so called 'yin-yang' pattern, in 2. Strong enhanced was found in all lesions, especially in 8 lesion with heterogeneous with the low T 2 signal. 'Dural tail' was found in 4 lesions. Conclusions: ISFI has some specific CT and MR features including heterogeneous signal intensity on T 2 WI, strong enhancement of areas with low T 2 signal intensity, slight or no 'dural tail', without skull thickening, and the typical 'yin-yang' pattern. (authors)

  13. A new technique for localization of hepatic tumors that are poorly visible with CT fluoroscopy

    International Nuclear Information System (INIS)

    Arrive, Lionel; Azizi, Louisa; Monnier-Cholley, Laurence; Lewin, Maite; Tubiana, Jean-Michel; Rosmorduc, Olivier; Beaussier, Marc

    2006-01-01

    The purpose of this study was to report a new technique for localization of hepatic tumors that are poorly visible with CT fluoroscopy. Forty-three hepatocellular carcinomas were not visible with CT fluoroscopy. A 22-gauge Chiba end-hole needle was inserted in the approximate location of a lesion estimated on the basis of anatomical landmarks demonstrated on both previous MR and CT images. We injected 3 ml of a mixture of nonionic contrast material and saline solution. Following the first injection, contrast solution filled the hepatic lesion in 29 of 43 cases. In 8 of 43 cases, contrast solution was distributed in the normal surrounding liver. In 7 of these 8 cases, repositioning allowed us to adjust the needle in the tumor. In the other 6 of 43 cases, contrast solution spread within capsule or pseudocapsule (pattern 3). In all 6 cases, repositioning allowed to adjust the needle in the tumor. This new technique allows an accurate localization of hepatic tumors that are poorly visible with CT fluoroscopy. (orig.)

  14. Application of CT perfusion imaging in radiotherapy for lung cancer

    International Nuclear Information System (INIS)

    Xia Guangrong; Liu Guimei; He Wen; Jin Guohua; Xie Ruming; Xu Yongxiang; Li Xiaobo; Li Xuebing

    2011-01-01

    Objective: To investigate the value of CT perfusion imaging in evaluation of therapeutic effect and prognosis in radiotherapy for lung cancer. Methods: Fifty-one cases of lung cancer who were unable or refused to be operated on, 36 males and 15 females, aged 37-80, underwent CT perfusion imaging, 29 of which only before radiotherapy and 22 before and after radiotherapy twice. The images were collected by cine dynamic scanning (5 mm/4 slices) and input into the GE AW4.0 workstation for data processing. The slice positions of CT imaging were determined according to the largest tumor size in CT scan. Regions of interest of tumor were drawn at the region corresponding to the original images of CT perfusion. Radiotherapy was performed after CT perfusion imaging. Relevant parameters, including blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface (PS) were calculated. The treatment response after radiotherapy was evaluated by RECIST. At 2 -4 weeks after the treatment, CT examination was conducted once more. Results: The tests of the 51 patients showed that the BV was 13.6 ml·100 g -1 , the BF was 129.5 ml·min -1 ·100 g -1 , the MTT was 9.1 s, and the PS was 10.0 ml· min -1 · 100 g -1 before radiotherapy. The tests of the 22 of the 51 patients showed that the values of BV and BF after radiotherapy were 7.6 ml· 100 g -1 and 97.8 ml·min -1 · 100 g -1 , respectively, both lower than those before radiotherapy (11.2 and 108.7 ml·min -1 ·100 g -1 , respectively), however, both not significantly (t=1.28, 0.40, P>0.05); and the values of MTT and PS after radiotherapy were 8.9 s and 7.8 ml·min -1 · 100 g -1 , respectively, both not significantly higher than those before radiotherapy (7.2 s and 6.8 ml· min -1 · 100 g -1 , respectively, t=-1.15, -0.57, P>0.05). The mean area of tumor after radiotherapy was 1189.6 mm 2 , significantly less than that before radiotherapy (1920.3 mm 2 , t=3.98, P<0.05). The MTT of the SCLC patients was 12

  15. Imaging analysis of colonic villous tumors

    International Nuclear Information System (INIS)

    Lee, Choon Hyeong; Lim, Joo Won; Lee, Dong Ho; Ko, Yung Tae; Yang, Ik

    1996-01-01

    To evaluate the CT and US features of the colonic villous tumors. We retrospectively reviewed the CT findings of 11 cases with histologically proved colonic villous tumor. CT parameters evaluated were morphological appearances and enhancing pattern (size, shape, margin, presence or absence of fronds, bowel wall thickening). CT features of six cases with malignant change were compared with five tumors without malignant change. US features available in 10 patients were also analyzed. On CT, the tumors showed irregular margin(n=9), presence of fronds(n=6), lobulated shape(n=11), with pericolonic invasion(n=1). Six cases with malignant change were larger(mean, 6.8 cm in diameter) than those without malignant change(mean, 3.3cm). US features in 10 cases were intraluminal mass(n=5), colonic wall thickening(n=5), with variable echogenicity. Colonic villous tumor appeared as a nonspecific mass on CT and US with a difficulty in distinguishing from colon carcinoma

  16. CT image in Reye syndrome

    International Nuclear Information System (INIS)

    Murayama, Takashi; Sakuma, Nobuko; Ishikawa, Akashi; Saito, Yoko; Takebayashi, Takeyasu; Kuwashima, Shigeru

    1983-01-01

    In a male infant with infantile spasms which had been observed, Reye's syndrome occurred at the age of 1 year and 6 months. CT findings, before the onset of Reye's syndrome, in the acute stage of the disease, and in the recovering stage, were obtained. The features of the disease were shown as low-absorption areas in the frontal and fronto-temporal areas of the head, and also strongly degenerative findings in the same areas, even in the recovery stage. This seemed to be characteristic to Reye's syndrome, and the basis of the suggestion was discussed. (Ueda, J.)

  17. High-field MR imaging of spinal cord tumors

    International Nuclear Information System (INIS)

    Halimi, P.; Sigal, R.; Blas, C.; Doyon, D.; Hurth, M.; Bittoun, J.

    1986-01-01

    In 60 patients with spinal cord tumors, MR imaging was performed using a 1.5-T unit (GE Signa) and a planar surface coil, 5-mm-thick sections, and spin-echo pulse sequences (TE/TR = 25/600 and 25-100/2,000-2,500 msec). There were 32 astrocytomas, 13 ependymomas, and five hemangioblastomas. Ten patients were not operated on. Surgical follow-up was available in 35 patients. The MR imaging results were correlated with findings on CT, myelography, intraoperative US, surgery, and pathologic examination. In all cases the tumor appeared markedly inhomogeneous. Four imaging patterns corresponding to structural abnormalities were observed: low signal intensity of the tumor core on both T1- and T2-weighted images; hypointensity on T1-weighted images and hyperintensity on T2-weighted images (low-protein cyst, syrinx, edema); isointensity on T1-weighted and slight hypertensity on T2-weighted images (high-protein tumoral necrotic cyst); and high spinal intensity on both T1- and T2-weighted images (chronic hemorrhage). MR imaging contributes the most information in the diagnosis of spinal cord tumors and delineation of their extent, and consequently has a potential impact on surgical management

  18. Congenital salivary gland anlage tumor - in utero and postnatal imaging

    Energy Technology Data Exchange (ETDEWEB)

    Radhakrishnan, Rupa; Calvo-Garcia, Maria A.; Koch, Bernadette L. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Lim, Foong-Yen [Cincinnati Children' s Hospital Medical Center, Division of Pediatric Surgery, Cincinnati, OH (United States); Elluru, Ravindhra G. [Cincinnati Children' s Hospital Medical Center, Division of Pediatric Otolaryngology, Cincinnati, OH (United States)

    2015-03-01

    We present a case of an infant with congenital salivary gland anlage tumor, with fetal and postnatal imaging. To the best of our knowledge, this is the first case describing the in utero imaging findings of salivary gland anlage tumor. A fetal MRI was performed secondary to the clinical finding of polyhydramnios, which identified a nasopharyngeal mass. Because findings were concerning for airway obstruction, the fetus was delivered by ex utero intrapartum treatment (EXIT) to airway procedure. A postnatal CT confirmed the findings of the fetal MRI. The lesion was resected when the baby was 4 days old and recovery was uneventful. (orig.)

  19. The diagnosis and therapeutic gain using US, CT and MRI. Submucosal tumors in stomach and duodenum

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, Shinichi; Nawano, Shigeru; Tajiri, Hisao; Boku, Narikazu; Muto, Manabu; Ohtsu, Atsushi; Yoshida, Shigeaki [National Cancer Center, Kashiwa, Chiba (Japan). Hospital East; Moriyama, Noriyuki

    1999-02-01

    The usefulness of the ultrasonography (US), the computed tomography (CT) and the magnetic resonance imaging (MRI) was examined. The subjects were 19 patients with submucosal leiomyoma and leiomyosarcoma in the stomach and duodenum which had surgery and were histologically diagnosed in the National Cancer Center Hospital. The detectability of the primary foci was 50% (8/16) in US, and 93% (13/14) in EUS (the endoscopic ultrasonography) which makes the structure of the stomach wall and the continuity of tumors clear. CT could detect the primary foci in 94% (16/17) and was excellent to know not only the presence of the remote metastases but also the exact size and expanse of the tumors. In all cases of leiomyoma, tumors were leiomyosarcoma when the internal structure was diagnosed to be heterogeneous by both EUS and CT, or either of them. The qualitative image diagnosis is not always easy in gastrointestinal submucosal tumors, but it is important to generally diagnose by the combination with several examinations in order to select the suitable therapeutic method. (K.H.)

  20. Active contour based segmentation of resected livers in CT images

    Science.gov (United States)

    Oelmann, Simon; Oyarzun Laura, Cristina; Drechsler, Klaus; Wesarg, Stefan

    2015-03-01

    The majority of state of the art segmentation algorithms are able to give proper results in healthy organs but not in pathological ones. However, many clinical applications require an accurate segmentation of pathological organs. The determination of the target boundaries for radiotherapy or liver volumetry calculations are examples of this. Volumetry measurements are of special interest after tumor resection for follow up of liver regrow. The segmentation of resected livers presents additional challenges that were not addressed by state of the art algorithms. This paper presents a snakes based algorithm specially developed for the segmentation of resected livers. The algorithm is enhanced with a novel dynamic smoothing technique that allows the active contour to propagate with different speeds depending on the intensities visible in its neighborhood. The algorithm is evaluated in 6 clinical CT images as well as 18 artificial datasets generated from additional clinical CT images.

  1. Bronchial carcinoid tumor: helical CT and virtual bronchoscopy

    International Nuclear Information System (INIS)

    Diez, Eduardo; Carrascosa, Patricia; Capunay, Carlos; Spinozzi, German; Abramson, Horacio; Berna, Miguel

    2001-01-01

    The authors reported a case of a 61 years old man with recurrent neumonia of the inferior right lobe diagnosed by a chest radiography. A complementary helical CT showed an endobronquial mass on the right intermediate bronchus. Virtual bronchoscopy contributed to a better definition of this lesion, confirmed by a real bronchoscopy. The lesion was diagnosed as a carcinoid tumor by a bronchial biopsy. After surgery (sleeve resection of the tumor) the patient did not show any recurrence of his broncho-neumonic clinical features. (author)

  2. TU-H-CAMPUS-JeP2-02: Interobserver Variability of CT, PET-CT and MRI Based Primary Tumor Delineation for Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Karki, K; Hugo, G; Saraiya, S; Jan, N; Schuster, J; Schutzer, M; Fahrner, L; Groves, R; Ford, J; Weiss, E [Virginia Commonwealth University, Richmond, VA (United States)

    2016-06-15

    Purpose: Target delineation in lung cancer radiotherapy has, in general, large variability. MRI has so far not been investigated in detail for lung cancer delineation variability. The purpose of this study is to investigate delineation variability for lung tumors using MRI and compare it to CT alone and PET-CT based delineations. Methods: Seven physicians delineated the primary tumor volumes of nine patients for the following scenarios: (1) CT only; (2) post-contrast T1-weighted MRI registered with diffusion-weighted MRI; and (3) PET-CT fusion images. To compute interobserver variability, the median surface was generated from all observers’ contours and used as the reference surface. A single physician labeled the interface types (tumor to lung, atelectasis (collapsed lung), hilum, mediastinum, or chest-wall) on the median surface. Volume variation (normalized to PET-CT volume), minimum distance (MD), and bidirectional local distance (BLD) between individual observers’ contours and the reference contour were measured. Results: CT- and MRI-based normalized volumes were 1.61±0.76 (mean±SD) and 1.38±0.44, respectively, both significantly larger than PET-CT (p<0.05, paired t-test). The overall uncertainty (root mean square of SD values over all points) of both BLD and MD measures of the observers for the interfaces were not significantly different (p>0.05, two-samples t-test) for all imaging modalities except between tumor-mediastinum and tumor-atelectasis in PET-CT. The largest mean overall uncertainty was observed for tumor-atelectasis interface, the smallest for tumor-mediastinum and tumor-lung interfaces for all modalities. The whole tumor uncertainties for both BLD and MD were not significantly different between any two modalities (p>0.05, paired t-test). Overall uncertainties for the interfaces using BLD were similar to using MD. Conclusion: Large volume variations were observed between the three imaging modalities. Contouring variability appeared to

  3. Hybrid SPECT/CT imaging in neurology.

    Science.gov (United States)

    Ciarmiello, Andrea; Giovannini, Elisabetta; Meniconi, Martina; Cuccurullo, Vincenzo; Gaeta, Maria Chiara

    2014-01-01

    In recent years, the SPECT/CT hybrid modality has led to a rapid development of imaging techniques in nuclear medicine, opening new perspectives for imaging staff and patients as well. However, while, the clinical role of positron emission tomography-computed tomography (PET-CT) is well consolidated, the diffusion and the consequent value of single-photon emission tomography-computed tomography (SPECT-CT) has yet to be weighed, Hence, there is a need for a careful analysis, comparing the "potential" benefits of the hybrid modality with the "established" ones of the standalone machine. The aim of this article is to analyze the impact of this hybrid tool on the diagnosis of diseases of the central nervous system, comparing strengths and weaknesses of both modalities through the use of SWOT analysis.

  4. Primary hyperparathyroidism, adrenal tumors and neuroendocrine tumors of the pancreas - clinical diagnosis and imaging requirements

    International Nuclear Information System (INIS)

    Auernhammer, C.J.; Engelhardt, D.; Goeke, B.

    2003-01-01

    Diseases of the parathyroids, the adrenals and of neuroendocrine tumors of the pancreas are primarily diagnosed by clinical and endocrinological evaluation.The requirements concerning various imaging techniques and their relative importance in localization strategies of the different tumors are complex. Current literature search, using PubMed. Evaluation of primary hyperparathyroidism requires bone densitometry by DXA and search for nephrolithiasis by ultrasound or native CT examination.While ultrasound of the thyroid and parathyroids seems useful before any parathyroid surgery,more extensive preoperative localization strategies (sestamibi scintigraphy, MRI) should be restricted to minimal invasive parathyroid surgery or re-operations.For adrenal tumors CT and MRI are of similar diagnostic value. Imaging of pheochromocytomas should be completed by MIBG scintigraphy. Each adrenal incidentaloma requires an endocrinological work-up.A fine-needle aspiration or core needle biopsy of an adrenal tumor is rarely indicated.Before adrenal biopsy a pheochromocytoma has to be excluded.Successful localization strategies for neuroendocrine tumors of the pancreas include somatostatin receptor scintigraphy, endoscopic ultrasound and MRI.Discussion Specific localization strategies have been established for the aforementioned tumors.The continuous progress of different imaging techniques requires a regular reevaluation of these localization strategies. (orig.) [de

  5. MRI and CT findings of the giant cell tumors of the skull; five cases and a review of the literature

    International Nuclear Information System (INIS)

    Kashiwagi, Nobuo; Hirabuki, Norio; Andou, Kumiko; Yoshifumi, Narumi; Tanaka, Hisashi; Morino, Hideo; Taki, Takuyu; Ishikura, Reiichi; Hirota, Seiichi; Onishi, Hiromitu; Nakamura, Hironobu

    2006-01-01

    Purpose: To investigate CT and MR findings of giant cell tumors (GCTs) of the skull, an unusual site for such tumors. Materials and methods: CT and MR features of five histologically proven giant cell tumors of the skull were retrospectively reviewed. We also reviewed 22 cases in the literature that included MR or CT findings. Results: Three of the tumors originated from the temporal bone with predominantly medial extension, and the other two were centered in the body of the sphenoid bone and featured symmetrical soft tissue extension. CT images with bone window settings showed reactive bone changes for all three tumors of the temporal bone, suggesting slow growth for example, an expanded intradiploic space, expansive remodelling and development of foci of pressure erosion. GCTs of the sphenoid bone showed purely osteolytic changes without remodelling. Although the MR signals and enhancement patterns varied, all the tumors of the temporal bone had a markedly low intensity area on T2-weighted images, which was not seen in the tumors of the sphenoid bone. The findings for our cases generally corresponded to those reported in the literature. Conclusion: Giant cell tumors of the skull have two preferential sites and may have characteristic tendencies as to their extent. Bone changes and MR signals appear to show differences between the two sites

  6. CT and MR images of pleomorphic adenoma in major and minor salivary glands

    International Nuclear Information System (INIS)

    Kakimoto, Naoya; Gamoh, Shoko; Tamaki, Junko; Kishino, Mitsunobu; Murakami, Shumei; Furukawa, Souhei

    2009-01-01

    Purpose: To investigate the CT and MR imaging features of pleomorphic adenoma in the head and neck area. Materials and methods: Our materials of this study consisted of 50 pleomorphic adenomas from 50 patients which were all histopathologically diagnosed. The CT and MR images were retrospectively evaluated. The following features were evaluated: the detectability of the lesion, the tumor margin, the border of the lesion, the aspect of the lesion, the contrast between the lesion and surrounding tissue, the signal intensity of the lesion, the enhancement of contrast medium, the aspect of the lesion after the injection of contrast medium, the detectability of the capsule, and the detectability of bone resorption of the lesion. Results: The tumor detectabilities were 77% on axial plain CT images and 90% on axial CE CT images, respectively. On CT images, pleomorphic adenoma tended to show a well-defined margin, a smooth border, an inhomogeneous aspect, a low or high contrast, and intermediate or high signal intensity. After contrast medium administration, pleomorphic adenoma tended to show a slightly high enhancement and either an inhomogeneous or a periphery enhancement on the CE CT images. The capsule could be hardly detected on CT images. The tumor detectabilities were 86% on axial T1-weighted MR images, 88% on axial T2-weighted MR images, and 85% on axial CE T1-weighted MR images, respectively. On MR images, pleomorphic adenomas tended to show well-defined margin, a lobulate border, an inhomogeneous aspect, a high contrast, and intermediate or high signal intensity. After contrast medium administration, pleomorphic adenoma tended to show a high enhancement and either an inhomogeneous or a periphery enhancement on MR images. The capsule could be detected in many cases on MR images. Conclusions: It was possible to detect the capsule in pleomorphic adenoma using MR images. The pleomorphic adenomas in head and neck area should be evaluated with MR images.

  7. CT imaging of necrosive fasciitis

    International Nuclear Information System (INIS)

    Schulze, M.; Overkamp, D.; Joanoviciu, S.; Horger, M.

    2008-01-01

    NF is a rare but dramatic and often fatal infection of the fascii and adjoining soft tissues. Contrary to the Fournier's definition, it is most common in elderly people. Patients with immune problems have a higher risk (e.g. Diabetes mellitus, alcohol or drug abuse, AIDS, leukaemia, chemotherapy and immunosuppressive medication). Predisposition factors are diverticulitis, insect bites, or surgical interventions (Uppot RN, Levy HM, PLatel PH, Radiology 2003; 226; 115; Wysoki MG, Santora TA, Shah RM et al. Necrotizing fasciitis: CT characteristics, Radiology 1997; 203;859). Men are affected more frequently than women. In principle, NF may occur everywhere in the body but incidence in the region of the scrotum, perineum and lower extremities are the most common. (orig.)

  8. CT findings in the leptomeningeal dissemination of tumors

    International Nuclear Information System (INIS)

    Yamazaki, Shingo; Ito, Umeo; Tomita, Hiroki; Takada, Yoshiaki; Ohno, Kikuo; Momma, Seiji; Inaba, Yutaka.

    1986-01-01

    The communicating hydrocephalus, the enhancement of the basal and quadrigeminal cisterns, and the enhancement of the Sylvian fissure, the cortical sulci and the ventricular wall are CT findings reported with regard to the leptomeningeal dissemination of tumors (LMDT). However, these findings are not always observed in patients with LMDT. In the present study, CT findings on 4 patients with LMDT (one from spinal ependymoblastoma, two from gastric cancer; and one from pulmonary cancer) are reported. Depending on the stage of the disease, the appearances of the above LMDT are quite varied. In Case 1, only hydrocephalus was found on admission CT. About one month later, the enhancement of the basal cisterns, the Sylvian fissure, the cerebral sulci, and the ventricular wall was observed, and this enhancement was further intensified later on. In Case 2, the cortical sulci were enhanced without any enhancement of the hydrocephalus or anything else. In Case 3, only the cerebral margin of the posterior lobectomy was enhanced. In Case 4, only a communicating hydrocephalus was observed. However, in all four cases the CSF cytology was positive for tumor cells. The frequency of each CT finding is discussed for the reported 25 cases. (author)

  9. 90Y microsphere therapy: does 90Y PET/CT imaging obviate the need for 90Y Bremsstrahlung SPECT/CT imaging?

    Science.gov (United States)

    Zade, Anand A; Rangarajan, Venkatesh; Purandare, Nilendu C; Shah, Sneha A; Agrawal, Archi R; Kulkarni, Suyash S; Shetty, Nitin

    2013-11-01

    Transarterial radioembolization using Y microspheres is a novel therapeutic option for inoperable hepatic malignancies. As these spheres are radiolucent, real-time assessment of their distribution during the infusion process under fluoroscopic guidance is not possible. Bremsstrahlung radiations arising from 90Y have conventionally been used for imaging its biodistribution. Recent studies have proved that sources of 90Y also emit positrons, which can further be used for PET/computed tomography (CT) imaging. This study aimed to assess the feasibility of 90Y PET/CT imaging in evaluating microsphere distributions and to compare its findings with those of Bremsstrahlung imaging. Thirty-five sessions of 90Y microsphere transarterial radioembolization were performed on 30 patients with hepatic malignancies. 90Y PET/CT imaging was performed within 3 h of therapy. Bremsstrahlung imaging was also performed for each patient. The imaging findings were compared for concordance in the distribution of microspheres. Exact one-to-one correspondence between 90Y PET/CT imaging and 90Y Bremsstrahlung imaging was observed in 97.14% of cases (i.e. in 34/35 cases). Discordance was observed only in one case in which 90Y PET/CT imaging resolved the microsphere uptake in the inferior vena cava tumor thrombus, which was, however, not visualized on Bremsstrahlung imaging. There is good concordance in the imaging findings of 90Y PET/CT and 90Y Bremsstrahlung imaging. 90Y PET/CT imaging scores over the conventionally used Bremsstrahlung imaging in terms of better resolution, ease of technique, and comparable image acquisition time. This makes it a preferred imaging modality for assessment of the distribution of 90Y microspheres.

  10. Registration of SPECT, PET and/or X-ray CT images in patients with lung cancer

    International Nuclear Information System (INIS)

    Uemura, K.; Toyama, H.; Miyamoto, T.; Yoshikawa, K.; Mori, Y.

    2002-01-01

    Aim: In order to evaluate the therapeutic gain of heavy ion therapy performed on patients with lung cancer, the regional pulmonary functions and the amount of radio tracer accumulation to the tumor, we are investigated by using the region of interest based on anatomical information obtained from X-ray CT. There are many registration techniques for brain images, but not so much for the other organ images that we have studied registration of chest SPECT, PET and/or X-ray CT images. Materials and Methods: Perfusion, ventilation and blood pool images with Tc 99m labeled radiopharmaceuticals and SPECT, tumor images with 11 C-methionine and PET and X-ray CT scans were performed on several patients with lung cancer before and after heavy ion therapy. The registrations of SPECT-CT, PET-CT and CT-CT were performed by using AMIR (Automatic Multimodality Image Registration), which was developed by Babak et al. for registration of brain images. In a case of SPECT-CT registration, each of the three functional images was registered to the X-ray CT image, and the accuracy of each registration was compared. In the studies of PET-CT registration, the transmission images and X-ray CT images were registered at first, because the 11 C-methionine PET images bear little resemblance to the underlying anatomical images. Next, the emission images were realigned by using the same registration parameters. The X-ray CT images obtained from a single subject at the different time were registered to the first X-ray CT images, respectively. Results: In the SPECT-CT registration, the blood pool-CT registration is the best among three SPECT images in visual inspection by radiologists. In the PET-CT registration, the Transmission-CT registrations got good results. Therefore, Emission-CT registrations also got good results. In the CT-CT registration, the X-ray CT images obtained from a single subject at the different time were superimposed well each other except for lower lobe. As the results, it was

  11. The clinical impact of {sup 18}F-FDG PET/CT in extracranial pediatric germ cell tumors

    Energy Technology Data Exchange (ETDEWEB)

    Hart, Adam; Vali, Reza; Marie, Eman; Shammas, Amer [The Hospital for Sick Children and University of Toronto, Department of Medical Imaging, Nuclear Medicine, Toronto, ON (Canada); Shaikh, Furqan [The Hospital for Sick Children and University of Toronto, Division of Haematology and oncology, Toronto, ON (Canada)

    2017-10-15

    Extracranial germ cell tumors are an uncommon pediatric malignancy with limited information on the clinical impact of {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the literature. The purpose of this study was to evaluate and compare the clinical impact on management of {sup 18}F-FDG PET/CT with diagnostic computed tomography (CT) in pediatric extracranial germ cell tumor. The list of {sup 18}F-FDG PET/CT performed for extracranial germ cell tumor between May 2007 and November 2015 was obtained from the nuclear medicine database. {sup 18}F-FDG PET/CT and concurrent diagnostic CT were obtained and independently reviewed. Additionally, the patients' charts were reviewed for duration of follow-up and biopsy when available. The impact of {sup 18}F-FDG PET/CT compared with diagnostic CT on staging and patient management was demonstrated by chart review, imaging findings and follow-up studies. During the study period, 9 children (5 males and 4 females; age range: 1.6-17 years, mode age: 14 years) had 11 {sup 18}F-FDG PET/CT studies for the evaluation of germ cell tumor. Diagnostic CTs were available for comparison in 8 patients (10 {sup 18}F-FDG PET/CT studies). The average interval between diagnostic CT and PET/CT was 7.2 days (range: 0-37 days). In total, five lesions concerning for active malignancy were identified on diagnostic CT while seven were identified on PET/CT. Overall, {sup 18}F-FDG PET/CT resulted in a change in management in 3 of the 9 patients (33%). {sup 18}F-FDG PET/CT had a significant impact on the management of pediatric germ cell tumors in this retrospective study. Continued multicenter studies are required secondary to the rarity of this tumor to demonstrate the benefit of {sup 18}F-FDG PET/CT in particular clinical scenarios. (orig.)

  12. Fast parallel algorithm for CT image reconstruction.

    Science.gov (United States)

    Flores, Liubov A; Vidal, Vicent; Mayo, Patricia; Rodenas, Francisco; Verdú, Gumersindo

    2012-01-01

    In X-ray computed tomography (CT) the X rays are used to obtain the projection data needed to generate an image of the inside of an object. The image can be generated with different techniques. Iterative methods are more suitable for the reconstruction of images with high contrast and precision in noisy conditions and from a small number of projections. Their use may be important in portable scanners for their functionality in emergency situations. However, in practice, these methods are not widely used due to the high computational cost of their implementation. In this work we analyze iterative parallel image reconstruction with the Portable Extensive Toolkit for Scientific computation (PETSc).

  13. Functioning islet cell tumor of the pancreas. Localization with dynamic spiral CT

    International Nuclear Information System (INIS)

    Chung, M.J.; Choi, B.I.; Han, J.K.; Chung, J.W.; Han, M.C.; Bae, S.H.

    1997-01-01

    Purpose: The purpose of this study was to evaluate the usefulness of dynamic spiral CT, including multidimensional reformation, in the detection and localization of islet cell tumors of the pancreas. Material and Methods: Seven patients with histopathologically proven functioning islet cell tumors of the pancreas were studied with 2-phase contrast-enhanced spiral CT. Scanning of the arterial phase and late phase was started 30 s and 180 s, respectively, after injection of 100 ml of contrast medium at a rate of 3 ml/s. Results: Axial images in the arterial phase depicted the lesions in 5 patients, but in the late phase in only one patient. Multiplanar reformatted images of the arterial phase depicted the lesions in all 7 patients. Maximal intensity projection images demonstrated all lesions with information of their relationship to the vascular structure. Conclusion: Dynamic spiral CT with scanning during the arterial phase and retrospective multidimensional reformation is useful for preoperative detection and localization of small islet cell tumors of the pancreas. (orig.)

  14. Quantitative CT analysis for the preoperative prediction of pathologic grade in pancreatic neuroendocrine tumors

    Science.gov (United States)

    Chakraborty, Jayasree; Pulvirenti, Alessandra; Yamashita, Rikiya; Midya, Abhishek; Gönen, Mithat; Klimstra, David S.; Reidy, Diane L.; Allen, Peter J.; Do, Richard K. G.; Simpson, Amber L.

    2018-02-01

    Pancreatic neuroendocrine tumors (PanNETs) account for approximately 5% of all pancreatic tumors, affecting one individual per million each year.1 PanNETs are difficult to treat due to biological variability from benign to highly malignant, indolent to very aggressive. The World Health Organization classifies PanNETs into three categories based on cell proliferative rate, usually detected using the Ki67 index and cell morphology: low-grade (G1), intermediate-grade (G2) and high-grade (G3) tumors. Knowledge of grade prior to treatment would select patients for optimal therapy: G1/G2 tumors respond well to somatostatin analogs and targeted or cytotoxic drugs whereas G3 tumors would be targeted with platinum or alkylating agents.2, 3 Grade assessment is based on the pathologic examination of the surgical specimen, biopsy or ne-needle aspiration; however, heterogeneity in the proliferative index can lead to sampling errors.4 Based on studies relating qualitatively assessed shape and enhancement characteristics on CT imaging to tumor grade in PanNET,5 we propose objective classification of PanNET grade with quantitative analysis of CT images. Fifty-five patients were included in our retrospective analysis. A pathologist graded the tumors. Texture and shape-based features were extracted from CT. Random forest and naive Bayes classifiers were compared for the classification of G1/G2 and G3 PanNETs. The best area under the receiver operating characteristic curve (AUC) of 0:74 and accuracy of 71:64% was achieved with texture features. The shape-based features achieved an AUC of 0:70 and accuracy of 78:73%.

  15. Imaging modalities in radiation treatment planning of brain tumors

    International Nuclear Information System (INIS)

    Georgiev, D.

    2009-01-01

    The radiation therapy is a standard treatment after surgery for most of malignant and some of benignant brain tumors. The restriction in acquiring local tumor control is an inability in realization of high dose without causing radiation necrosis in irradiated area and sparing normal tissues. The development of imaging modalities during the last years is responsible for better treatment results and lower early and late toxicity. Essential is the role of image methods not only in the diagnosis and also in the precise anatomical (during last years also functional) localisation, spreading of the tumor, treatment planning process and the effects of the treatment. Target delineation is one of the great geometrical uncertainties in the treatment planning process. Early studies on the use of CT in treatment planning documented that tumor coverage without CT was clearly inadequate in 20% of the patients and marginal in another 27 %. The image fusion of CT, MBI and PET and also the use of contrast materia helps to get over those restrictions. The use of contrast material enhances the signal in 10 % of the patients with glioblastoma multiform and in a higher percentage of the patients with low-grade gliomas

  16. Artifacts in conventional computed tomography (CT) and free breathing four-dimensional CT induce uncertainty in gross tumor volume determination

    DEFF Research Database (Denmark)

    Persson, Gitte Fredberg; Nygaard, Ditte Eklund; Af Rosenschöld, Per Munck

    2011-01-01

    was to compare delineated gross tumor volume (GTV) sizes in 3DCT, 4DCT, and BHCT scans of patients with lung tumors. METHODS AND MATERIALS: A total of 36 patients with 46 tumors referred for stereotactic radiotherapy of lung tumors were included. All patients underwent positron emission tomography (PET)/CT, 4DCT...

  17. Clinical application of early PET-CT imaging after radiofrequency ablation of liver neoplasms

    International Nuclear Information System (INIS)

    Liu Zhaoyu; Chang Zhihui; Lu Zaiming; Xin Jun; Wang Xiaoming; Guo Qiyong

    2009-01-01

    Objective: To evaluate the application of early 18 F-FDG PET-CT imaging after radiofrequency ablation (RFA) of hepatic malignancies. Methods: Fifteen patients with liver tumors (five hepatocellular carcinoma, ten colorectal cancer liver metastasis) underwent RFA as part of clinical management. The lesions were all hypermetabolic on PET-CT performed within 2 weeks prior to RFA. All subjects underwent 18 F-FDG PET-CT (early PET-CT) within 24 hours after RFA. Total photopenia, focal uptake, and rim-shaped uptake were regarded as complete ablation, residual tumor, and inflammation, respectively. Follow-up PET-CT scans were performed as the reference standard. Results: Twelve patients showed total photopenia at the ablation site on the early PET-CT scan, and in all of these patients, total photopenia at the ablation sites was seen on the follow-up PET-CT scans. Two patients had focal uptake at the ablation sites on the early PET-CT scan, and both of these foci increased in size and intensity, which were compatible with residual tumors at the time of ablation. Only one patient had rim-shaped uptake on the early PET-CT scan. The rim-shaped uptake disappeared on PET-CT performed 3 months later, which indicated the nature of inflammation. Conclusions: There is infrequent inflammatory uptake at the RFA site of liver tumors on 18 F-FDG PET-CT if scanning is performed within 24 hours after ablation. Thus, early PET- CT has the potential to evaluate the efficacy of an RFA procedure by indicating tumor-free as total photopenia and residual tumors as focal uptake. (authors)

  18. The accuracy of CT and tumor markers in the detection of a recurrent ovarian carcinoma

    International Nuclear Information System (INIS)

    Wakabayashi, Yukari; Ishida, Jiro; Kotake, Fumio; Hirose, Masahiro; Kawana, Koji; Abe, Kimihiko; Amino, Saburo; Negishi, Yoshiyuki; Akiya, Kiyoshi

    1989-01-01

    Twenty-three patients previously diagnosed as having ovarian cancer were examined with both serum tumor markers (CA 125, CA 19-9, TPA, IAP, AFP) and a pelvic CT scan. The tumor markers predict the clinical outcome more accurately than the CT scan. Further, the tumor markers showed a clear correlation with the clinical course. But in one case, however, the tumor markers were seen to reduce below the normal level from chemotherapy, while the CT scan showed a tumor mass. Thus, both, a CT scan and tumor marker assays are felt to be indispensable for detecting the recurrence of an ovarian cancer. (author)

  19. Institut Gustave Roussy method for head and neck tumor treatment planning using simulator-CT images and radiographic film data; Methode utilisee a l'institut Gustave Roussy pour l'etablissement des plans de traitement des cancers ORL a partir des images de simulateur-scanneur et du film radiographique de profil

    Energy Technology Data Exchange (ETDEWEB)

    Bridier, A.; Barrois, M.M.; Rivet, P. [Institut Gustave Roussy, Service de Physique, 94 - Villejuif (France); Diaz, J.C.; Kafrouni, H.; Leclerc, A. [Institut Gustave Roussy, Activite Dosigray, 94 - Villejuif (France); Wibault, P.; Bourhis, J.; Eschwege, F. [Institut Gustave Roussy, Dept. de Radiotherapie, 94 - Villejuif (France)

    2001-06-01

    Institut Gustave Roussy method for head and neck tumor treatment planning using simulator-CT images and radiographic film data. The paper deals with the recent improvements introduced in the most usual method applied in the Institut Gustave Roussy radiotherapy department for obtaining the anatomical data of patients treated for head and neck tumors. For each of these patients, five to seven transverses slices and a lateral radiographic film are taken from a Mecaserto simulator-CT. The anatomical representation of the patient sagittal plane is carried out from the digitalization of the radiographic film on a Vidar Vxr-12 Plus film scanner and integrated into the Dosigray dose calculation programme in order to be used as a support for the laying out of the dose distribution in reference to the treatment. The sagittal anatomical representation obtained from the radiographic film digitalization is compared with the one resulting from the interpolation between a limited number of irregularly-spaced transverse slices taken on the simulator-CT. The method using the simulator-scanner transverse slices and the radiographic film digitalization represents an interesting alternative for obtaining an anatomy simulation representative of the patient in hospitals where a scanner is not available full-time for the needs of the radiotherapy process. (authors)

  20. Management of Renal Tumors by Image-Guided Radiofrequency Ablation: Experience in 105 Tumors

    International Nuclear Information System (INIS)

    Breen, David J.; Rutherford, Elizabeth E.; Stedman, Brian; Roy-Choudhury, Shuvro H.; Cast, James E. I.; Hayes, Matthew C.; Smart, Christopher J.

    2007-01-01

    Aims. In this article we present our experience with radiofrequency ablation (RFA) in the treatment of 105 renal tumors. Materials and Methods. RFA was performed on 105 renal tumors in 97 patients, with a mean tumor size of 32 mm (11-68 mm). The mean patient age was 71.7 years (range, 36-89 years). The ablations were carried out under ultrasound (n = 43) or CT (n = 62) guidance. Imaging follow-up was by contrast-enhanced CT within 10 days and then at 6-monthly intervals. Multivariate analysis was performed to determine variables associated with procedural outcome. Results. Eighty-three tumors were completely treated at a single sitting (79%). Twelve of the remaining tumors were successfully re-treated and a clinical decision was made not to re-treat seven patients. A patient with a small residual crescent of tumor is under follow-up and may require further treatment. In another patient, re-treatment was abandoned due to complicating pneumothorax and difficult access. One patient is awaiting further re-treatment. The overall technical success rate was 90.5%. Multivariate analysis revealed tumor size to be the only significant variable affecting procedural outcome. (p = 0.007, Pearson χ 2 ) Five patients had complications. There have been no local recurrences. Conclusion. Our experience to date suggests that RFA is a safe and effective, minimally invasive treatment for small renal tumors

  1. Diagnosis of tumors of the pituitary region by two-plane CT scans

    International Nuclear Information System (INIS)

    Murata, Minoru; Inoue, Hiroshi; Misumi, Shuzo; Shimizu, Tsuneo; Tamura, Masaru

    1981-01-01

    Thirty five cases of tumors in the pituitary region were analysed by two-plane CT (ordinary sections and reverse sections) in order to obtain a more accurate image of the tumor and thus establish an appropriate indication for the subnasal transsphenoidal approach. The tumors of pituitary region were classified into six groups (types I-VI) according to their degree of extension and direction of growth. Small tumors such as types I and II were detected more clearly by the reverse section than by the ordinary section. In cases of large tumors (types III-VI) relation of the tumor to the surrounding structures such as the sphenoid sinus, third ventricle, lateral ventricule, middle fossa and brain stem was accurately demonstrated by the reverse section. In the differential diagnosis of tumors in the pituitary regions, tumors showing mixed density or slightly high density and widening of the anteroposterior diameter of the sella in the precontrast reverse section and homogeneous enhancement by infusion were likely to be pituitary adenomas. One third of the pituitary adenomas showed ring-like high density in the post-contrast reverse section. Calcification was not seen in the pituitary adenomas by CT scans. All craniopharyngiomas belonged to types III-VI. Craniopharyngiomas showed high and/or low density, and various degrees of calcification in plain CT scans. Ring-like high density was seen in two thirds of the craniopharyngiomas. About one third of the craniopharyngiomas showed widening of the antero-posterior diameter of the sella. (J.P.N.)

  2. Maximum-intensity-projection CT angiography for evaluating head and neck tumors. Usefulness of helical CT and auto bone masking method

    International Nuclear Information System (INIS)

    Sakai, Osamu; Nakashima, Noriko; Ogawa, Chiaki; Shen, Yun; Takata, Yasunori; Azemoto, Shougo.

    1994-01-01

    Angiographic images of 10 adult patients with head and neck tumors were obtained by helical computed tomography (CT) using maximum intensity projection (MIP). In all cases, the vasculature of the head and neck region was directly demonstrated. In the head and neck, bone masking is a more important problem than in other regions. We developed an effective automatic bone masking method (ABM) using 2D/3D connectivity. Helical CT angiography with MIP and ABM provided accurate anatomic depiction, and was considered to be helpful in preoperative evaluation of head and neck tumors. (author)

  3. CT imaging spectrum of infiltrative renal diseases.

    Science.gov (United States)

    Ballard, David H; De Alba, Luis; Migliaro, Matias; Previgliano, Carlos H; Sangster, Guillermo P

    2017-11-01

    Most renal lesions replace the renal parenchyma as a focal space-occupying mass with borders distinguishing the mass from normal parenchyma. However, some renal lesions exhibit interstitial infiltration-a process that permeates the renal parenchyma by using the normal renal architecture for growth. These infiltrative lesions frequently show nonspecific patterns that lead to little or no contour deformity and have ill-defined borders on CT, making detection and diagnosis challenging. The purpose of this pictorial essay is to describe the CT imaging findings of various conditions that may manifest as infiltrative renal lesions.

  4. A phantom study of tumor contouring on PET imaging

    International Nuclear Information System (INIS)

    Chen Song; Li Xuena; Li Yaming; Yin Yafu; Li Na; Han Chunqi

    2010-01-01

    Objective: To explore an algorithm to define the threshold value for tumor contouring on 18 F-fluorodeoxyglucose (FDG) PET imaging. Methods: A National Electrical Manufacturing Association (NEMA)NU 2 1994 PET phantom with 5 spheres of different diameters were filled with 18 F-FDG. Seven different sphere-to-background ratios were obtained and the phantom was scanned by Discovery LS 4. For each sphere-to-background ratio, the maximum standardized uptake value (SUV max ) of each sphere, the SUV of the border of each sphere (SUV border ), the mean SUV of a 1 cm region of background (SUV bg ) and the diameter (D) of each sphere were measured. SPSS 13.0 software was used for curve fitting and regression analysis to obtain the threshold algorithm. The calculated thresholds were applied to delineate 29 pathologically confirmed lung cancer lesions on PET images and the obtained volumes were compared with the volumes contoured on CT images in lung window. Results: The algorithm for defining contour threshold is TH% = 33.1% + 46.8% SUV bg /SUV max + 13.9%/D (r = 0.994) by phantom studies. For 29 lung cancer lesions, the average gross tumor volumes (GTV) delineated on PET and CT are (7.36±1.62) ml and (8.31±2.05) ml, respectively (t = -1.26, P>0.05). Conclusion: The proposed threshold algorithm for tumor contouring on PET image could provide comparable GTV with CT. (authors)

  5. Myocardial perfusion imaging with dual energy CT

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, SMG-SNU Boramae Medical Center, Seoul (Korea, Republic of); De Cecco, Carlo N. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncology and Pathology, University of Rome “Sapienza”, Rome (Italy); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Spandorfer, Adam; Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States)

    2016-10-15

    Highlights: • Stress dual-energy sCTMPI offers the possibility to directly detect the presence of myocardial perfusion defects. • Stress dual-energy sCTMPI allows differentiating between reversible and fixed myocardial perfusion defects. • The combination of coronary CT angiography and dual-energy sCTMPI can improve the ability of CT to detect hemodynamically relevant coronary artery disease. - Abstract: Dual-energy CT (DECT) enables simultaneous use of two different tube voltages, thus different x-ray absorption characteristics are acquired in the same anatomic location with two different X-ray spectra. The various DECT techniques allow material decomposition and mapping of the iodine distribution within the myocardium. Static dual-energy myocardial perfusion imaging (sCTMPI) using pharmacological stress agents demonstrate myocardial ischemia by single snapshot images of myocardial iodine distribution. sCTMPI gives incremental values to coronary artery stenosis detected on coronary CT angiography (CCTA) by showing consequent reversible or fixed myocardial perfusion defects. The comprehensive acquisition of CCTA and sCTMPI offers extensive morphological and functional evaluation of coronary artery disease. Recent studies have revealed that dual-energy sCTMPI shows promising diagnostic accuracy for the detection of hemodynamically significant coronary artery disease compared to single-photon emission computed tomography, invasive coronary angiography, and cardiac MRI. The aim of this review is to present currently available DECT techniques for static myocardial perfusion imaging and recent clinical applications and ongoing investigations.

  6. Imaging of abdominal tumours: CT or MRI?

    International Nuclear Information System (INIS)

    Olsen, Oeystein E.

    2009-01-01

    The scope of this review is to discuss a theoretical approach to imaging policy, particularly in the perspective of radiation risk reduction. Decisions are ideally driven by empirical evidence about efficacy and risk, e.g., in classical hierarchical efficacy model. As a result of the paucity of empirical evidence (inevitable because of rapid technological development), a pragmatic model is needed. This should avoid overemphasis of factors that currently seem to hamper change, namely personal preference, local expertise, infrastructure, availability. Extrapolation of current general knowledge about CT and MRI demonstrates how a pragmatic approach can be applied in the real world with intermediate goals such as (1) channeling patients from CT to MRI, and (2) reducing CT-delivered radiation. Increased utilisation of MRI in body imaging requires optimisation of scan protocols and equipment, and, being a very operator-dependent modality, the active involvement of the radiologist. In CT dose reduction the main challenge is to benchmark the minimum radiation-dose requirement, and therefore the minimum required image quality that is diagnostically acceptable. As this will ultimately depend on pre-test likelihoods in institutional populations, it is difficult to issue general guidance, and local assessment remains a cornerstone in this effort. (orig.)

  7. An unusual mature thyroid teratoma on CT and {sup 99}Tcm scintigraphy imaging in a child

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu-Zhen; Li, Wen-Hua; Li, Yu-Hua; Gao, Yu [Xin Hua Hospital, Shanghai Jiaotong University School of Medicine, Department of Radiology, Shanghai (China); Zhu, Ming-Jie [Xin Hua Hospital, Shanghai Jiaotong University School of Medicine, Department of Radiology, Shanghai (China); Xin Hua Hospital, Shanghai Jiaotong University School of Medicine, Department of Pathology, Shanghai (China)

    2010-11-15

    We report the imaging findings of a mature thyroid teratoma in a 5-year-old girl. Nuclear imaging showed a decrease in {sup 99}Tcm uptake in the right lobe of the thyroid gland. CT scan showed a slightly lobulated soft-tissue mass without calcification, fat or cystic components. Histological analysis showed that the tumor was composed of mature neural tissue, cartilaginous, and epithelial elements. This case study provides new insights into the CT appearance of mature thyroid teratomas. (orig.)

  8. Dual-time-point FDG-PET/CT Imaging of Temporal Bone Chondroblastoma: A Report of Two Cases

    Directory of Open Access Journals (Sweden)

    Akira Toriihara

    2015-07-01

    Full Text Available Temporal bone chondroblastoma is an extremely rare benign bone tumor. We encountered two cases showing similar imaging findings on computed tomography (CT, magnetic resonance imaging (MRI, and dual-time-point 18F-fluorodeoxyglucose (18F-FDG positron emission tomography (PET/CT. In both cases, CT images revealed temporal bone defects and sclerotic changes around the tumor. Most parts of the tumor showed low signal intensity on T2- weighted MRI images and non-uniform enhancement on gadolinium contrast-enhanced T1-weighted images. No increase in signal intensity was noted in diffusion-weighted images. Dual-time-point PET/CT showed markedly elevated 18F-FDG uptake, which increased from the early to delayed phase. Nevertheless, immunohistochemical analysis of the resected tumor tissue revealed weak expression of glucose transporter-1 and hexokinase II in both tumors. Temporal bone tumors, showing markedly elevated 18F-FDG uptake, which increases from the early to delayed phase on PET/CT images, may be diagnosed as malignant bone tumors. Therefore, the differential diagnosis should include chondroblastoma in combination with its characteristic findings on CT and MRI.

  9. Target coverage in image-guided stereotactic body radiotherapy of liver tumors.

    Science.gov (United States)

    Wunderink, Wouter; Méndez Romero, Alejandra; Vásquez Osorio, Eliana M; de Boer, Hans C J; Brandwijk, René P; Levendag, Peter C; Heijmen, Ben J M

    2007-05-01

    To determine the effect of image-guided procedures (with computed tomography [CT] and electronic portal images before each treatment fraction) on target coverage in stereotactic body radiotherapy for liver patients using a stereotactic body frame (SBF) and abdominal compression. CT guidance was used to correct for day-to-day variations in the tumor's mean position in the SBF. By retrospectively evaluating 57 treatment sessions, tumor coverage, as obtained with the clinically applied CT-guided protocol, was compared with that of alternative procedures. The internal target volume-plus (ITV(+)) was introduced to explicitly include uncertainties in tumor delineations resulting from CT-imaging artifacts caused by residual respiratory motion. Tumor coverage was defined as the volume overlap of the ITV(+), derived from a tumor delineated in a treatment CT scan, and the planning target volume. Patient stability in the SBF, after acquisition of the treatment CT scan, was evaluated by measuring the displacement of the bony anatomy in the electronic portal images relative to CT. Application of our clinical protocol (with setup corrections following from manual measurements of the distances between the contours of the planning target volume and the daily clinical target volume in three orthogonal planes, multiple two-dimensional) increased the frequency of nearly full (> or = 99%) ITV(+) coverage to 77% compared with 63% without setup correction. An automated three-dimensional method further improved the frequency to 96%. Patient displacements in the SBF were generally small (design, patient stability in the SBF should be verified with portal imaging.

  10. Imaging of bone tumors and tumor-like lesions. Techniques and applications

    International Nuclear Information System (INIS)

    Davies, A. Mark; Sundaram, Murali; James, Steven L.J.

    2009-01-01

    This is a comprehensive textbook that provides a detailed description of the imaging techniques and findings in patients with benign and malignant bone tumors. In the first part of the book, the various techniques and procedures employed for imaging bone tumors are discussed in detail. Individual chapters are devoted to MRI, CT, nuclear medicine, and interventional procedures. The second part of the book gives an authoritative review of the role of these imaging techniques in diagnosis, surgical staging, biopsy, and assessment of response to therapy. The third part of the book covers the imaging features of each major tumor subtype, with separate chapters on osteogenic tumors, cartilaginous tumors, etc. The final part of the book reviews the imaging features of bone tumors at particular anatomical sites such as the spine, ribs, pelvis, and scapula. Each chapter is written by an acknowledged expert in the field, and a wealth of illustrative material is included. This book will be of great value to musculoskeletal and general radiologists, orthopedic surgeons, and oncologists. (orig.)

  11. Assessment of intratumor hypoxia by integrated 18F-FDG PET / perfusion CT in a liver tumor model.

    Directory of Open Access Journals (Sweden)

    Yong Wang

    Full Text Available Hypoxia in solid tumors occurs when metabolic demands in tumor cells surpass the delivery of oxygenated blood. We hypothesize that the 18F-fluorodeoxyglucose (18F-FDG metabolism and tumor blood flow mismatch would correlate with tumor hypoxia.Liver perfusion computed tomography (CT and 18F-FDG positron emission tomography (PET imaging were performed in twelve rabbit livers implanted with VX2 carcinoma. Under CT guidance, a fiber optic probe was inserted into the tumor to measure the partial pressure of oxygen (pO2. Tumor blood flow (BF and standardized uptake value (SUV were measured to calculate flow-metabolism ratio (FMR. Tumor hypoxia was further identified using pimonidazole immunohistochemical staining. Pearson correlation analysis was performed to determine the correlation between the imaging parameters and pO2 and pimonidazole staining.Weak correlations were found between blood volume (BV and pO2 level (r = 0.425, P = 0.004, SUV and pO2 (r = -0.394, P = 0.007, FMR and pimonidazole staining score (r = -0.388, P = 0.031. However, there was stronger correlation between tumor FMR and pO2 level (r = 0.557, P < 0.001.FMR correlated with tumor oxygenation and pimonidazole staining suggesting it may be a potential hypoxic imaging marker in liver tumor.

  12. Assessment of tumors of the lung apex by imaging techniques

    International Nuclear Information System (INIS)

    Rueda, J.; Serrano, F.; Pain, M.I.; Rodriguez, F.

    1996-01-01

    The purpose of this study was to analyze the value of MR in the preoperative staging of tumors of the lung apex and detection of local invasion of adjacent structures to determine its influence on the therapeutic approach. We obtained plain X-ray images in two planes, as well as CT and Mr images, in 12 patients with Pan coast tumor in whom there was surgical (n=8) or clinical (n=4) evidence of invasion. The objective was to assess local infiltration of brain stem and chest wall soft tissue, enveloping of the subclavian artery, substantial involvement of the brachial plexus and destruction of the vertebral body. In our series, MR was superior to the other imaging techniques in predicting the involvement of the structures surrounding the tumor. In conclusion, MR should be performed in a patient diagnosed by plain radiography as having an apical tumors to assess local tumor extension, while CT should be done to detect mediastinal lymph node involvement and distant metastases. 19 refs

  13. CT Imaging of Craniofacial Fibrous Dysplasia

    Directory of Open Access Journals (Sweden)

    Zerrin Unal Erzurumlu

    2015-01-01

    Full Text Available Fibrous dysplasia is a benign fibroosseous bone dysplasia that can involve single (monostotic or multiple (polyostotic bones. Monostotic form is more frequent in the jaws. It is termed as craniofacial fibrous dysplasia, when it involves, though rarely, adjacent craniofacial bones. A 16-year-old girl consulted for a painless swelling in the right posterior mandible for two years. Panoramic radiography revealed ground-glass ill-defined lesions in the three different regions of the maxilla and mandible. Axial CT scan (bone window showed multiple lesions involving skull base and facial bones. Despite lesions in the skull base, the patient had no abnormal neurological findings. The lesion was diagnosed as fibrous dysplasia based on radiological and histopathological examination. In this paper, CT findings and differential diagnosis of CFD are discussed. CT is a useful imaging technique for CFD cases.

  14. Malignant fatty tumors: classification, clinical course, imaging appearance and treatment

    International Nuclear Information System (INIS)

    Peterson, J.J.; Kransdorf, M.J.; Bancroft, L.W.; O'Connor, M.I.

    2003-01-01

    Liposarcoma is a relatively common soft tissue malignancy with a wide spectrum of clinical presentations and imaging appearances. Several subtypes are described, ranging from lesions nearly entirely composed of mature adipose tissue, to tumors with very sparse adipose elements. The imaging appearance of these fatty masses is frequently sufficiently characteristic to allow a specific diagnosis, while in other cases, although a specific diagnosis is not achievable, a meaningful limited differential diagnosis can be established. The purpose of this paper is to review the spectrum of malignant fatty tumors, highlighting the current classification system, clinical presentation and behavior, treatment and spectrum of imaging appearances. The imaging review will emphasize CT scanning and MR imaging, and will stress differentiating radiologic features. (orig.)

  15. Algorithms of CT value correction for reconstructing a radiotherapy simulation image through axial CT images

    International Nuclear Information System (INIS)

    Ogino, Takashi; Egawa, Sunao

    1991-01-01

    New algorithms of CT value correction for reconstructing a radiotherapy simulation image through axial CT images were developed. One, designated plane weighting method, is to correct CT value in proportion to the position of the beam element passing through the voxel. The other, designated solid weighting method, is to correct CT value in proportion to the length of the beam element passing through the voxel and the volume of voxel. Phantom experiments showed fair spatial resolution in the transverse direction. In the longitudinal direction, however, spatial resolution of under slice thickness could not be obtained. Contrast resolution was equivalent for both methods. In patient studies, the reconstructed radiotherapy simulation image was almost similar in visual perception of the density resolution to a simulation film taken by X-ray simulator. (author)

  16. Evaluation of pulmonary emphysema by the fused image of CT image and ventilation SPECT image

    International Nuclear Information System (INIS)

    Okuda, Ituko; Maruno, Hiromasa; Mori, Kazuaki; Kohno, Tadashi; Kokubo, Takashi

    2007-01-01

    We evaluated pulmonary emphysema using a diagnostic device that could obtain a CT image, a ventilation single photon emission computed tomography (SPECT) image and a lung perfusion SPECT image in one examination. The fused image made from the CT image and SPECT image had very little position gap between images, and the precision was high. From the fused image, we were able to detect the areas in which emphysematous change was the most marked in the CT image, while the accumulation decrease was most remarkable in the ventilation SPECT image. Thus it was possible to obtain an accurate status of pulmonary emphysema, and our method was regarded as a useful technique. (author)

  17. Importance of Preoperative Rectal Ultrasound and CT in Rectal Tumors

    International Nuclear Information System (INIS)

    Schnellyova, T.

    2011-01-01

    Introduction: The reason of high mortality of colorectal carcinoma is above all the fact, that majority of diseases are detected in progressive stage. Radical change in this unfavorable mortality rate can be achieved only by targeted search for early stages of the disease. Early diagnostics consists in rectoscopy and colonoscopy. Regarding X-ray methods it is X-ray irigography. Regarding CT examinations it is CT irigography, virtual colonoscopy. Another examination can be USG examination of abdomen and endo sonographic examination of rectum. Materials and methods: In the period from June 2006 to December 2010, in 60 patients out of the total number 106 examined patients, tumorous affection of rectum CT examination of pelvis and abdomen separately or pelvisand abdomen at one session was made in 3186 patients. In 115 patients we discovered malign tumorous illness of colon. Metastatic affection in the form of distant metastases was proven n 63 patients. 403 patients had CT irigography examination. In 77 out of them we diagnosed colon carcinoma. CT colonoscopy did not discover in our group of 30 patients examined the presence of colon carcinoma. Results: In the group of 60 patients who were diagnosed rectal carcinoma, in 29 patients expansive infiltrative affection was evaluated in endorectal sonography, histologically confirmed in 28 patients - 96,5 %, expansive affection in 41 patients with histological verification in 100 %. With CT we diagnosed 52 expansive tumorous processes, histologically confirmed in 47 patients - 90,38 %. In 63 patients expansive infiltrative process was evaluated, histologically confirmed in 52 patients 82,53 %. In total of 115 examinations there was conformance with histological examination in 99 patients - 86,08 %. In CT irigography we diagnosed colon tumour in 77 patients. Expansive growth was evaluated in 40 patients, histologically confirmed in 37 patients - 92,5 %. Expansive infiltrative expansion was evaluated in 37 patients, with

  18. Brain's tumor image processing using shearlet transform

    Science.gov (United States)

    Cadena, Luis; Espinosa, Nikolai; Cadena, Franklin; Korneeva, Anna; Kruglyakov, Alexey; Legalov, Alexander; Romanenko, Alexey; Zotin, Alexander

    2017-09-01

    Brain tumor detection is well known research area for medical and computer scientists. In last decades there has been much research done on tumor detection, segmentation, and classification. Medical imaging plays a central role in the diagnosis of brain tumors and nowadays uses methods non-invasive, high-resolution techniques, especially magnetic resonance imaging and computed tomography scans. Edge detection is a fundamental tool in image processing, particularly in the areas of feature detection and feature extraction, which aim at identifying points in a digital image at which the image has discontinuities. Shearlets is the most successful frameworks for the efficient representation of multidimensional data, capturing edges and other anisotropic features which frequently dominate multidimensional phenomena. The paper proposes an improved brain tumor detection method by automatically detecting tumor location in MR images, its features are extracted by new shearlet transform.

  19. Tumor Localization Using Cone-Beam CT Reduces Setup Margins in Conventionally Fractionated Radiotherapy for Lung Tumors

    International Nuclear Information System (INIS)

    Yeung, Anamaria R.; Li, Jonathan G.; Shi Wenyin; Newlin, Heather E.; Chvetsov, Alexei; Liu, Chihray; Palta, Jatinder R.; Olivier, Kenneth

    2009-01-01

    Purpose: To determine whether setup margins can be reduced using cone-beam computed tomography (CBCT) to localize tumor in conventionally fractionated radiotherapy for lung tumors. Methods and Materials: A total of 22 lung cancer patients were treated with curative intent with conventionally fractionated radiotherapy using daily image guidance with CBCT. Of these, 13 lung cancer patients had sufficient CBCT scans for analysis (389 CBCT scans). The patients underwent treatment simulation in the BodyFix immobilization system using four-dimensional CT to account for respiratory motion. Daily alignment was first done according to skin tattoos, followed by CBCT. All 389 CBCT scans were retrospectively registered to the planning CT scans using automated soft-tissue and bony registration; the resulting couch shifts in three dimensions were recorded. Results: The daily alignment to skin tattoos with no image guidance resulted in systematic (Σ) and random (σ) errors of 3.2-5.6 mm and 2.0-3.5 mm, respectively. The margin required to account for the setup error introduced by aligning to skin tattoos with no image guidance was approximately 1-1.6 cm. The difference in the couch shifts obtained from the bone and soft-tissue registration resulted in systematic (Σ) and random (σ) errors of 1.5-4.1 mm and 1.8-5.3 mm, respectively. The margin required to account for the setup error introduced using bony anatomy as a surrogate for the target, instead of localizing the target itself, was 0.5-1.4 cm. Conclusion: Using daily CBCT soft-tissue registration to localize the tumor in conventionally fractionated radiotherapy reduced the required setup margin by up to approximately 1.5 cm compared with both no image guidance and image guidance using bony anatomy as a surrogate for the target.

  20. Combined FDG-PET/CT for the detection of unknown primary tumors: systematic review and meta-analysis

    International Nuclear Information System (INIS)

    Kwee, Thomas C.; Kwee, Robert M.

    2009-01-01

    The aim of this study was to systematically review and meta-analyze published data on the diagnostic performance of combined 18F-fluoro-2-deoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in the detection of primary tumors in patients with cancer of unknown primary (CUP). A systematic search for relevant studies was performed of the PubMed/MEDLINE and Embase databases. Methodological quality of the included studies was assessed. Reported detection rates, sensitivities and specificities were meta-analyzed. Subgroup analyses were performed if results of individual studies were heterogeneous. The 11 included studies, comprising a total sample size of 433 patients with CUP, had moderate methodological quality. Overall primary tumor detection rate, pooled sensitivity and specificity of FDG-PET/CT were 37%, 84% (95% CI 78-88%) and 84% (95% CI 78-89%), respectively. Sensitivity was heterogeneous across studies (P = 0.0001), whereas specificity was homogeneous across studies (P = 0.2114). Completeness of diagnostic workup before FDG-PET/CT, location of metastases of unknown primary, administration of CT contrast agents, type of FDG-PET/CT images evaluated and way of FDG-PET/CT review did not significantly influence diagnostic performance. In conclusion, FDG-PET/CT can be a useful method for unknown primary tumor detection. Future studies are required to prove the assumed advantage of FDG-PET/CT over FDG-PET alone and to further explore causes of heterogeneity. (orig.)

  1. Brain CT image and handedness of schizophrenia

    International Nuclear Information System (INIS)

    Hirose, Katsutoshi; Maehara, Katsuya; Iizuka, Reiji; Mikami, Akihiro.

    1989-01-01

    Brain CT images were reviewed of 98 schizophrenic patients and 90 healthy persons in relation to handedness and aging. CT images were further reconstructed to examine morphologically subtle changes in each region. Schizophrenic patients had progressive brain atrophy and dilated lateral ventricles, especially on the left side and in the posterior part of the lateral ventricle. These findings were more marked in left-handed than in right-handed schizophrenic patients. According to age groups, there were significant differences between schizophrenic and normal persons over the age of 40. The incidence of left handedness was significantly higher in schizophrenic patients in their fourties than the age-matched normal persons (31.4% vs 15.1%). Morphological abnormality and laterality might be due to the same pathologic consequences. (N.K.)

  2. Comparative study of CT and MR guided cryoablation for hepatic tumors

    International Nuclear Information System (INIS)

    Wu Bin; Xiao Yueyong; Zhang Xiao; Li Hongjun; Li Jie; Yu Da

    2010-01-01

    Objective: To compare CT and MR imaging in guiding and monitor/ng cryoablation of hepatic tumors. Methods: A total of 131 lesions in 121 patients with malignant tumors of liver were treated with imaging-guided percutaneous cryotherapy. There were 73 males and 48 females, mean age 60 years. Of the 121 patients, 61 patients had cryoablation under CT guidance and 60 patients under the guidance of MRI. CT-guidance was performed with the Philips big-bore CT in spiral mode, with 5 mm slice thickness. The MR guidance was performed with GE 0.35 T scanner assisted with infrared navigator (Xinaomdt), and both fast gradient echo sequence and fast spin-echo sequence were used. The cryoablation system is a magnetic resonance compatible system (Galil, Israel), equipped with 17 G cryoprobes that are 1.47 mm in outside diameter. A combination of multiple cryo-probes and conformal cryoablation were adopted in accordance with the location, the shape and the adjacent structure of each lesion. Each cryoablation included two freezing-thawing cycles. Scanning was performed intermittently during the operation to monitor the degree of ablation. The mean scanning time, the lesion depiction and ablation process monitoring, the efficacies of lesion ablation, complications,and survival time were analyzed with χ 2 test. Results: The mean scanning time was (5.6±1.8) min for CT and (22.0±2.6) min for MR. CT provided a good depiction of the lesion and the ribs which were poorly displayed on MR images. The metal probe could create artifacts on the CT images and it was difficult for CT to show the formation of ice ball of the lesion formed after embolization with lipiodol. MR was superior to CT in displaying, guiding and monitoring of ablation of lesions near such special regions as the diaphragm dome, the hepatic hilum, and the gallbladder. MR was not affected by high-density embolization material and the metal probes, and thus was superior to CT in depicting the lesion, and monitoring the

  3. Multi-modality PET-CT imaging of breast cancer in an animal model using nanoparticle x-ray contrast agent and 18F-FDG

    Science.gov (United States)

    Badea, C. T.; Ghaghada, K.; Espinosa, G.; Strong, L.; Annapragada, A.

    2011-03-01

    Multi-modality PET-CT imaging is playing an important role in the field of oncology. While PET imaging facilitates functional interrogation of tumor status, the use of CT imaging is primarily limited to anatomical reference. In an attempt to extract comprehensive information about tumor cells and its microenvironment, we used a nanoparticle xray contrast agent to image tumor vasculature and vessel 'leakiness' and 18F-FDG to investigate the metabolic status of tumor cells. In vivo PET/CT studies were performed in mice implanted with 4T1 mammary breast cancer cells.Early-phase micro-CT imaging enabled visualization 3D vascular architecture of the tumors whereas delayedphase micro-CT demonstrated highly permeable vessels as evident by nanoparticle accumulation within the tumor. Both imaging modalities demonstrated the presence of a necrotic core as indicated by a hypo-enhanced region in the center of the tumor. At early time-points, the CT-derived fractional blood volume did not correlate with 18F-FDG uptake. At delayed time-points, the tumor enhancement in 18F-FDG micro-PET images correlated with the delayed signal enhanced due to nanoparticle extravasation seen in CT images. The proposed hybrid imaging approach could be used to better understand tumor angiogenesis and to be the basis for monitoring and evaluating anti-angiogenic and nano-chemotherapies.

  4. Three-Dimensional Segmentation of the Tumor in Computed Tomographic Images of Neuroblastoma

    OpenAIRE

    Deglint, Hanford J.; Rangayyan, Rangaraj M.; Ayres, Fábio J.; Boag, Graham S.; Zuffo, Marcelo K.

    2006-01-01

    Segmentation of the tumor in neuroblastoma is complicated by the fact that the mass is almost always heterogeneous in nature; furthermore, viable tumor, necrosis, and normal tissue are often intermixed. Tumor definition and diagnosis require the analysis of the spatial distribution and Hounsfield unit (HU) values of voxels in computed tomography (CT) images, coupled with a knowledge of normal anatomy. Segmentation and analysis of the tissue composition of the tumor can assist in quantitative ...

  5. NMR imaging of soft tissue tumors

    International Nuclear Information System (INIS)

    Laval-Jeantet, M.; Tobolsk, F.; Delepine, N.; Delepine, G.; Roger, B.; Cabanis, E.A.

    1986-01-01

    Preliminary findings on NMR imaging of 30 soft tissue tumors demonstrated the indispensable value of this examination (particularly when a surface antenna is used) for preoperative investigation and diagnosis of tumoral recurrence when compared with other radiologic techniques. The possible potential of NMR imaging for characterization of tissues, apart from lipoma or liposarcoma, cannot be evaluated at the present time [fr

  6. Iatrogenic intraspinal epidermoid tumor: Myelo-CT and MRI diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Visciani, A.; Balestrini, M.R.; Solero, C.L.; Savoiardo, M.

    1989-07-01

    An 11-year-old boy, treated for acute lymphatic leukemia at the age of 2 with intrathecal injections of Methotrexate, presented with a two year history of pain and signs of lumbo-sacral lesion. MRI, myelography and myelo-CT demonstrated an intradural L4-L5 epidermoid tumor which was removed. Iatrogenic implantation of epithelial cells at the age of two with lumbar punctures is most likely. Decline in incidence of lumbar iatrogenic epidermoid cysts, now an exceedingly rare event, is probably related to improved needles for lumbar punctures. (orig.).

  7. Iatrogenic intraspinal epidermoid tumor: Myelo-CT and MRI diagnosis

    International Nuclear Information System (INIS)

    Visciani, A.; Balestrini, M.R.; Solero, C.L.; Savoiardo, M.

    1989-01-01

    An 11-year-old boy, treated for acute lymphatic leukemia at the age of 2 with intrathecal injections of Methotrexate, presented with a two year history of pain and signs of lumbo-sacral lesion. MRI, myelography and myelo-CT demonstrated an intradural L4-L5 epidermoid tumor which was removed. Iatrogenic implantation of epithelial cells at the age of two with lumbar punctures is most likely. Decline in incidence of lumbar iatrogenic epidermoid cysts, now an exceedingly rare event, is probably related to improved needles for lumbar punctures. (orig.)

  8. Cone-beam volume CT mammographic imaging: feasibility study

    Science.gov (United States)

    Chen, Biao; Ning, Ruola

    2001-06-01

    X-ray projection mammography, using a film/screen combination or digital techniques, has proven to be the most effective imaging modality for early detection of breast cancer currently available. However, the inherent superimposition of structures makes small carcinoma (a few millimeters in size) difficult to detect in the occultation case or in dense breasts, resulting in a high false positive biopsy rate. The cone-beam x-ray projection based volume imaging using flat panel detectors (FPDs) makes it possible to obtain three-dimensional breast images. This may benefit diagnosis of the structure and pattern of the lesion while eliminating hard compression of the breast. This paper presents a novel cone-beam volume CT mammographic imaging protocol based on the above techniques. Through computer simulation, the key issues of the system and imaging techniques, including the x-ray imaging geometry and corresponding reconstruction algorithms, x-ray characteristics of breast tissues, x-ray setting techniques, the absorbed dose estimation and the quantitative effect of x-ray scattering on image quality, are addressed. The preliminary simulation results support the proposed cone-beam volume CT mammographic imaging modality in respect to feasibility and practicability for mammography. The absorbed dose level is comparable to that of current two-view mammography and would not be a prominent problem for this imaging protocol. Compared to traditional mammography, the proposed imaging protocol with isotropic spatial resolution will potentially provide significantly better low contrast detectability of breast tumors and more accurate location of breast lesions.

  9. Differentiation of primary chordoma, giant cell tumor and schwannoma of the sacrum by CT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Si, Ming-Jue, E-mail: smjsh@hotmail.com [Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Wang, Cheng-Sheng [Department of Radiology, Union Hospital, Fujian Medical University, Fuzhou 350001 (China); Ding, Xiao-Yi, E-mail: dingxiaoyi1965@hotmail.com [Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Yuan, Fei, E-mail: yuanfeirj@hotmail.com [Department of Pathology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Du, Lian-Jun; Lu, Yong [Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Zhang, Wei-Bin [Department of Orthopedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China)

    2013-12-01

    Objective: To evaluate criteria to differentiate sacral chordoma (SC), sacral giant cell tumor (SGCT) and giant sacral schwannoma (GSS) with CT and MRI. Materials and methods: CT and MR images of 22 SCs, 19 SGCTs and 8 GSSs were reviewed. The clinical and imaging features of each tumor were analyzed. Results: The mean ages of SC, SGCT and GSS were 55.1 ± 10.7, 34.3 ± 10.7 and 42.4 ± 15.7 years old. SCs (77.3%) were predominantly located in the midline of lower sacrum, while most SGCTs (73.7%) and GSSs (87.5%) were eccentrically located in upper sacrum. There were significant differences in age, location, eccentricity, morphology of bone residues, intratumoral bleeding and septations. Multiple small cysts were mainly observed in SGCTs (73.7%) with large central cysts in GSSs (87.5%). SGCTs expanded mainly inside sacrum while SCs and GSSs often extended into pelvic cavity (P = 0.0022). Involvement of sacroiliac joints and muscles were also different. Ascending extension within sacral canal was only displayed in SCs. The preservation of intervertebral discs showed difference between large and small tumors (P = 0.0002), regardless of tumor type (P = 0.095). No significant difference was displayed in gender (P = 0.234) or tumor size (P = 0.0832) among three groups. Conclusion: Age, epicenter of the lesion (midline vs. eccentric and upper vs. lower sacral vertebra), bone residues, cysts, bleeding, septation, expanding pattern, muscles and sacroiliac joint involvement can be criteria for diagnosis. Fluid–fluid level is specific for SGCTs and ascending extension within the sacral canal for SCs. The preservation of intervertebral discs is related to tumor size rather than tumor type.

  10. An algorithm for 4D CT image sorting using spatial continuity.

    Science.gov (United States)

    Li, Chen; Liu, Jie

    2013-01-01

    4D CT, which could locate the position of the movement of the tumor in the entire respiratory cycle and reduce image artifacts effectively, has been widely used in making radiation therapy of tumors. The current 4D CT methods required external surrogates of respiratory motion obtained from extra instruments. However, respiratory signals recorded by these external makers may not always accurately represent the internal tumor and organ movements, especially when irregular breathing patterns happened. In this paper we have proposed a novel automatic 4D CT sorting algorithm that performs without these external surrogates. The sorting algorithm requires collecting the image data with a cine scan protocol. Beginning with the first couch position, images from the adjacent couch position are selected out according to spatial continuity. The process is continued until images from all couch positions are sorted and the entire 3D volume is produced. The algorithm is verified by respiratory phantom image data and clinical image data. The primary test results show that the 4D CT images created by our algorithm have eliminated the motion artifacts effectively and clearly demonstrated the movement of tumor and organ in the breath period.

  11. SU-F-207-06: CT-Based Assessment of Tumor Volume in Malignant Pleural Mesothelioma

    International Nuclear Information System (INIS)

    Qayyum, F; Armato, S; Straus, C; Husain, A; Vigneswaran, W; Kindler, H

    2015-01-01

    Purpose: To determine the potential utility of computed tomography (CT) scans in the assessment of physical tumor bulk in malignant pleural mesothelioma patients. Methods: Twenty-eight patients with malignant pleural mesothelioma were used for this study. A CT scan was acquired for each patient prior to surgical resection of the tumor (median time between scan and surgery: 27 days). After surgery, the ex-vivo tumor volume was measured by a pathologist using a water displacement method. Separately, a radiologist identified and outlined the tumor boundary on each CT section that demonstrated tumor. These outlines then were analyzed to determine the total volume of disease present, the number of sections with outlines, and the mean volume of disease per outlined section. Subsets of the initial patient cohort were defined based on these parameters, i.e. cases with at least 30 sections of disease with a mean disease volume of at least 3mL per section. For each subset, the R- squared correlation between CT-based tumor volume and physical ex-vivo tumor volume was calculated. Results: The full cohort of 28 patients yielded a modest correlation between CT-based tumor volume and the ex-vivo tumor volume with an R-squared value of 0.66. In general, as the mean tumor volume per section increased, the correlation of CT-based volume with the physical tumor volume improved substantially. For example, when cases with at least 40 CT sections presenting a mean of at least 2mL of disease per section were evaluated (n=20) the R-squared correlation increased to 0.79. Conclusion: While image-based volumetry for mesothelioma may not generally capture physical tumor volume as accurately as one might expect, there exists a set of conditions in which CT-based volume is highly correlated with the physical tumor volume. SGA receives royalties and licensing fees through the University of Chicago for computer-aided diagnosis technology

  12. SU-F-207-06: CT-Based Assessment of Tumor Volume in Malignant Pleural Mesothelioma

    Energy Technology Data Exchange (ETDEWEB)

    Qayyum, F; Armato, S; Straus, C; Husain, A; Vigneswaran, W; Kindler, H [The University of Chicago, Chicago, IL (United States)

    2015-06-15

    Purpose: To determine the potential utility of computed tomography (CT) scans in the assessment of physical tumor bulk in malignant pleural mesothelioma patients. Methods: Twenty-eight patients with malignant pleural mesothelioma were used for this study. A CT scan was acquired for each patient prior to surgical resection of the tumor (median time between scan and surgery: 27 days). After surgery, the ex-vivo tumor volume was measured by a pathologist using a water displacement method. Separately, a radiologist identified and outlined the tumor boundary on each CT section that demonstrated tumor. These outlines then were analyzed to determine the total volume of disease present, the number of sections with outlines, and the mean volume of disease per outlined section. Subsets of the initial patient cohort were defined based on these parameters, i.e. cases with at least 30 sections of disease with a mean disease volume of at least 3mL per section. For each subset, the R- squared correlation between CT-based tumor volume and physical ex-vivo tumor volume was calculated. Results: The full cohort of 28 patients yielded a modest correlation between CT-based tumor volume and the ex-vivo tumor volume with an R-squared value of 0.66. In general, as the mean tumor volume per section increased, the correlation of CT-based volume with the physical tumor volume improved substantially. For example, when cases with at least 40 CT sections presenting a mean of at least 2mL of disease per section were evaluated (n=20) the R-squared correlation increased to 0.79. Conclusion: While image-based volumetry for mesothelioma may not generally capture physical tumor volume as accurately as one might expect, there exists a set of conditions in which CT-based volume is highly correlated with the physical tumor volume. SGA receives royalties and licensing fees through the University of Chicago for computer-aided diagnosis technology.

  13. Nephrogenic rests mimicking Wilms' tumor on CT

    Energy Technology Data Exchange (ETDEWEB)

    Subhas, Naveen; Siegelman, Stanley S. [Russell H. Morgan Department of Radiology, The Johns Hopkins Hospital and School of Medicine, 600 N. Wolfe St., 21287, Baltimore, MD (United States); Argani, Pedram [Department of Pathology, Johns Hopkins Hospital and School of Medicine, 21287, Baltimore, MD (United States); Gearhart, John P. [Department of Pediatric Urology, Brady Urologic Institute, The Johns Hopkins Hospital and School of Medicine, 21287, Baltimore, MD (United States)

    2004-02-01

    Nephrogenic rests (NR) are persistent benign remnants of embryonic renal tissue. A small percentage of these may develop into Wilms' tumor (WT). Radiologic imaging is relied upon to differentiate between these entities, with the hallmark of malignant transformation being growth on serial imaging studies. There is, however, considerable overlap in their imaging characteristics. The authors present a case of two biopsy-proven NR in a 2-year-old girl with sporadic aniridia that were indistinguishable from WT on initial radiologic studies. One of the NR grew on serial imaging studies mimicking a WT, but after resection was confirmed to be a benign hyperplastic NR on pathologic examination. (orig.)

  14. A technique of using gated-CT images to determine internal target volume (ITV) for fractionated stereotactic lung radiotherapy

    International Nuclear Information System (INIS)

    Jin Jianyue; Ajlouni, Munther; Chen Qing; Yin, Fang-Fang; Movsas, Benjamin

    2006-01-01

    Background and purpose: To develop and evaluate a technique and procedure of using gated-CT images in combination with PET image to determine the internal target volume (ITV), which could reduce the planning target volume (PTV) with adequate target coverage. Patients and methods: A skin marker-based gating system connected to a regular single slice CT scanner was used for this study. A motion phantom with adjustable motion amplitude was used to evaluate the CT gating system. Specifically, objects of various sizes/shapes, considered as virtual tumors, were placed on the phantom to evaluate the number of phases of gated images required to determine the ITV while taking into account tumor size, shape and motion. A procedure of using gated-CT and PET images to define ITV for patients was developed and was tested in patients enrolled in an IRB approved protocol. Results: The CT gating system was capable of removing motion artifacts for target motion as large as 3-cm when it was gated at optimal phases. A phantom study showed that two gated-CT scans at the end of expiration and the end of inspiration would be sufficient to determine the ITV for tumor motion less than 1-cm, and another mid-phase scan would be required for tumors with 2-cm motion, especially for small tumors. For patients, the ITV encompassing visible tumors in all sets of gated-CT and regular spiral CT images seemed to be consistent with the target volume determined from PET images. PTV expanded from the ITV with a setup uncertainty margin had less volume than PTVs from spiral CT images with a 10-mm generalized margin or an individualized margin determined at fluoroscopy. Conclusions: A technique of determining the ITV using gated-CT images was developed and was clinically implemented successfully for fractionated stereotactic lung radiotherapy

  15. Imaging of bone tumors for the musculoskeletal oncologic surgeon.

    Science.gov (United States)

    Errani, C; Kreshak, J; Ruggieri, P; Alberghini, M; Picci, P; Vanel, D

    2013-12-01

    The appropriate diagnosis and treatment of bone tumors requires close collaboration between different medical specialists. Imaging plays a key role throughout the process. Radiographic detection of a bone tumor is usually not challenging. Accurate diagnosis is often possible from physical examination, history, and standard radiographs. The location of the lesion in the bone and the skeleton, its size and margins, the presence and type of periosteal reaction, and any mineralization all help determine diagnosis. Other imaging modalities contribute to the formation of a diagnosis but are more critical for staging, evaluation of response to treatment, surgical planning, and follow-up.When necessary, biopsy is often radioguided, and should be performed in consultation with the surgeon performing the definitive operative procedure. CT is optimal for characterization of the bone involvement and for evaluation of pulmonary metastases. MRI is highly accurate in determining the intraosseous extent of tumor and for assessing soft tissue, joint, and vascular involvement. FDG-PET imaging is becoming increasingly useful for the staging of tumors, assessing response to neoadjuvant treatment, and detecting relapses.Refinement of these and other imaging modalities and the development of new technologies such as image fusion for computer-navigated bone tumor surgery will help surgeons produce a detailed and reliable preoperative plan, especially in challenging sites such as the pelvis and spine. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  16. Using {sup 18F} FDG PET/CT to Detect an occult Mesenchymal Tumor Causing Oncogenic Osteomalacia

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Hyo Jung; Choi, Yun Jung; Kim, Hyun Jeong; Jeong, Yong Hyu; Cho, Arthur; Lee, Jae Hoon; Yun, Mijin; Lee, Jong Doo; Kang, Won Jun [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

    2011-09-15

    Oncogenic osteomalacia is a rare paraneoplastic syndrome characterized by renal phosphate excretion, hypophosphatemia, and osteomalacia. This syndrome is often caused by tumors of mesenchymal origin. Patients with oncogenic osteomalacia have abnormal bone mineralization, resulting in a high frequency of fractures. Tumor resection is the treatment of choice, as it will often correct the metabolic imbalance. Although oncogenic osteomalacia is a potentially curable disease, diagnosis is difficult and often delayed because of the small size and sporadic location of the tumor. Bone scintigraphy and radiography best characterize osteoma lacia; magnetic resonance imaging findings are nonspecific. Here, we report a case of oncogenic osteomalacia secondary to a phosphaturic mesenchymal tumor that was successfully detected by {sup 18F} fluorodeoxyglucose positron emission tomography/computed tomography ({sup 18F} FDG PET/CT). This case illustrates the advantages of {sup 18F} FDG PET/CT in detecting the occult mesenchymal tumor that causes oncogenic osteomalacia.

  17. MR imaging of the brain: tumors

    International Nuclear Information System (INIS)

    Sartor, K.

    1999-01-01

    The radiologic modality that most likely provides the imaging information needed in a patient suspected of having a brain tumor is MR imaging. A brain tumor can be reliably ruled out if the MR examination is performed properly and experts interpret the results as negative. If there is a tumor, however, its exact location and topography must be determined. Important for therapy and prognosis are also tumor properties such as histologic type and grade, as well as effects on adjacent brain structures. Although potentially a noninvasive method of in vivo neuropathology, MR is still far from being sufficiently specific, as dissimilar lesions may look the same despite the use of refined imaging protocols. The evolution of MR imaging continues, however, making further methodologic improvement likely. Presently, advanced methods, such as diffusion- and perfusion-weighted MR imaging, functional MR imaging, neuronavigation based on MR imaging data, and the use of MR imaging during surgery (intraoperative MR imaging), influence the way patients are treated. Likewise, follow-up imaging (monitoring) of tumor patients by MR has become more effective, and experience has shown how to distinguish reactive changes from recurrent tumor. In the future, MR imaging may gain importance in the development of novel therapeutic concepts. (orig.)

  18. Implications of CT noise and artifacts for quantitative 99mTc SPECT/CT imaging

    International Nuclear Information System (INIS)

    Hulme, K. W.; Kappadath, S. C.

    2014-01-01

    Purpose: This paper evaluates the effects of computed tomography (CT) image noise and artifacts on quantitative single-photon emission computed-tomography (SPECT) imaging, with the aim of establishing an appropriate range of CT acquisition parameters for low-dose protocols with respect to accurate SPECT attenuation correction (AC). Methods: SPECT images of two geometric and one anthropomorphic phantom were reconstructed iteratively using CT scans acquired at a range of dose levels (CTDI vol = 0.4 to 46 mGy). Resultant SPECT image quality was evaluated by comparing mean signal, background noise, and artifacts to SPECT images reconstructed using the highest dose CT for AC. Noise injection was performed on linear-attenuation (μ) maps to determine the CT noise threshold for accurate AC. Results: High levels of CT noise (σ ∼ 200–400 HU) resulted in low μ-maps noise (σ ∼ 1%–3%). Noise levels greater than ∼10% in 140 keV μ-maps were required to produce visibly perceptible increases of ∼15% in 99m Tc SPECT images. These noise levels would be achieved at low CT dose levels (CTDI vol = 4 μGy) that are over 2 orders of magnitude lower than the minimum dose for diagnostic CT scanners. CT noise could also lower (bias) the expected μ values. The relative error in reconstructed SPECT signal trended linearly with the relative shift in μ. SPECT signal was, on average, underestimated in regions corresponding with beam-hardening artifacts in CT images. Any process that has the potential to change the CT number of a region by ∼100 HU (e.g., misregistration between CT images and SPECT images due to motion, the presence of contrast in CT images) could introduce errors in μ 140 keV on the order of 10%, that in turn, could introduce errors on the order of ∼10% into the reconstructed 99m Tc SPECT image. Conclusions: The impact of CT noise on SPECT noise was demonstrated to be negligible for clinically achievable CT parameters. Because CT dose levels that affect

  19. Registration of 3D FMT and CT Images of Mouse via Affine Transformation using Sequential Monte Carlo

    International Nuclear Information System (INIS)

    Xia Zheng; Zhou Xiaobo; Wong, Stephen T. C.; Sun Youxian

    2007-01-01

    It is difficult to directly co-register the 3D FMT (Fluorescence Molecular Tomography) image of a small tumor in a mouse whose maximal diameter is only a few mm with a larger CT image of the entire animal that spans about ten cm. This paper proposes a new method to register 2D flat and 3D CT image first to facilitate the registration between small 3D FMT images and large CT images. A novel algorithm based on SMC (Sequential Monte Carlo) incorporated with least square operation for the registration between the 2D flat and 3D CT images is introduced and validated with simulated images and real images of mice. The visualization of the preliminary alignment of the 3D FMT and CT image through 2D registration shows promising results

  20. Parallel CT image reconstruction based on GPUs

    International Nuclear Information System (INIS)

    Flores, Liubov A.; Vidal, Vicent; Mayo, Patricia; Rodenas, Francisco; Verdú, Gumersindo

    2014-01-01

    In X-ray computed tomography (CT) iterative methods are more suitable for the reconstruction of images with high contrast and precision in noisy conditions from a small number of projections. However, in practice, these methods are not widely used due to the high computational cost of their implementation. Nowadays technology provides the possibility to reduce effectively this drawback. It is the goal of this work to develop a fast GPU-based algorithm to reconstruct high quality images from under sampled and noisy projection data. - Highlights: • We developed GPU-based iterative algorithm to reconstruct images. • Iterative algorithms are capable to reconstruct images from under sampled set of projections. • The computer cost of the implementation of the developed algorithm is low. • The efficiency of the algorithm increases for the large scale problems

  1. Usefulness of emission CT in 67Ga tumor and inflammation scintigraphy

    International Nuclear Information System (INIS)

    Koizumi, Kiyoshi; Tada, Akira; Bunko, Hisashi; Tonami, Norihisa; Hisada, Kinichi.

    1983-01-01

    67 Ga-citrate widely used for tumor imaging has some drawbacks. Poor blood elearance of 67 Ga is sometimes a cause of poor visualization of the abnormal uptake in lesions. Physiological accumulations of 67 Ga (e. g. liver, colon, pulmonary hilus, etc.) also conceal the abnormal 67 Ga uptake in lesions. We have evaluated the usefulness of 67 Ga SPECT (single photon emission CT) to overcome these drawbacks inherent in conventional gamma-camera images. 67 Ga SPECT was more useful to recognize the location and the extension of lesions in transaxial planes, therefore, comparison of the lesions with transmission CT was easily made. Abnormal accumulation in or near the liver was easily discriminated from the physiological accumulation of 67 Ga in the liver. Further evaluation of the lesions which had been detected by other imaging methods (e. g. transmission CT, ultrasonography, etc.), 67 Ga SPECT was more useful than conventional gamma-camera imaging. In conclusion, 67 Ga SPECT was useful in selected cases when performed after conventiond 67 Ga imaging. (author)

  2. Adrenal neoplasms: Effectiveness and safety of CT-guided ablation of 23 tumors in 22 patients

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, Farrah J.; Dupuy, Damian E.; Machan, Jason T. [Department of Diagnostic Imaging and the Office of Research Administration, Alpert Medical School of Brown University, Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903 (United States); Mayo-Smith, William W., E-mail: wmayo-smith@lifespan.org [Department of Diagnostic Imaging and the Office of Research Administration, Alpert Medical School of Brown University, Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903 (United States)

    2012-08-15

    Purpose: To retrospectively evaluate the effectiveness and safety of image-guided ablation of adrenal tumors. Materials and methods: : This HIPAA-compliant study was IRB approved and informed consent was waived. From 5/1999-6/2008, 20 consecutive adrenal metastases (mean diameter 4.2 cm; range, 2-8) and 3 hormonally active primary adrenal tumors (mean diameter 2.3 cm; range, 1-4), including an aldosteronoma and 2 pheochromocytomas in 22 patients (14 men, 8 women; mean age 61 years; range 40-84) were ablated in 23 sessions. Bilateral metastases were treated in a single patient. Radiofrequency ablation was used to treat 16 adrenal metastases and the 3 hyperfunctioning tumors. Microwave ablation was used to treat 4 metastases. Successful treatment was defined as a lack of both enhancement on follow-up contrast enhanced CT and/or up-take on FDG PET-CT and for functioning tumors, resolution of biochemical abnormalities. Results: Technical success was achieved in all sessions. Mean follow-up was 45.1 months (range, 1-91) Local tumor progression (focal enhancement at ablation site {>=}1 cm in short axis) was detected in 4 of 23 tumors, two of which were identified bilaterally in a single patient prompting re-treatment. Of 19 patients with metastatic disease, 16 had fatal extra-adrenal disease progression, and 3 remain alive. Two of the 3 patients who underwent ablation of hyperfunctioning tumors remain alive, including the patient with an aldosteronoma who had recurrent symptoms 91 months post ablation. Intra-ablative hypertension occurred in 9% (2/23) of sessions and was successfully treated pharmacologically. Conclusion: Ablation of metastatic and hyperfunctioning adrenal tumors is safe and may provide local control and treatment of pathologic biochemical activity.

  3. Adrenal neoplasms: Effectiveness and safety of CT-guided ablation of 23 tumors in 22 patients

    International Nuclear Information System (INIS)

    Wolf, Farrah J.; Dupuy, Damian E.; Machan, Jason T.; Mayo-Smith, William W.

    2012-01-01

    Purpose: To retrospectively evaluate the effectiveness and safety of image-guided ablation of adrenal tumors. Materials and methods: : This HIPAA-compliant study was IRB approved and informed consent was waived. From 5/1999-6/2008, 20 consecutive adrenal metastases (mean diameter 4.2 cm; range, 2–8) and 3 hormonally active primary adrenal tumors (mean diameter 2.3 cm; range, 1–4), including an aldosteronoma and 2 pheochromocytomas in 22 patients (14 men, 8 women; mean age 61 years; range 40–84) were ablated in 23 sessions. Bilateral metastases were treated in a single patient. Radiofrequency ablation was used to treat 16 adrenal metastases and the 3 hyperfunctioning tumors. Microwave ablation was used to treat 4 metastases. Successful treatment was defined as a lack of both enhancement on follow-up contrast enhanced CT and/or up-take on FDG PET-CT and for functioning tumors, resolution of biochemical abnormalities. Results: Technical success was achieved in all sessions. Mean follow-up was 45.1 months (range, 1–91) Local tumor progression (focal enhancement at ablation site ≥1 cm in short axis) was detected in 4 of 23 tumors, two of which were identified bilaterally in a single patient prompting re-treatment. Of 19 patients with metastatic disease, 16 had fatal extra-adrenal disease progression, and 3 remain alive. Two of the 3 patients who underwent ablation of hyperfunctioning tumors remain alive, including the patient with an aldosteronoma who had recurrent symptoms 91 months post ablation. Intra-ablative hypertension occurred in 9% (2/23) of sessions and was successfully treated pharmacologically. Conclusion: Ablation of metastatic and hyperfunctioning adrenal tumors is safe and may provide local control and treatment of pathologic biochemical activity.

  4. Source position error influence on industry CT image quality

    International Nuclear Information System (INIS)

    Cong Peng; Li Zhipeng; Wu Haifeng

    2004-01-01

    Based on the emulational exercise, the influence of source position error on industry CT (ICT) image quality was studied and the valuable parameters were obtained for the design of ICT. The vivid container CT image was also acquired from the CT testing system. (authors)

  5. The value of {sup 18}F-FDG PET/CT in the management of malignant peripheral nerve sheath tumors

    Energy Technology Data Exchange (ETDEWEB)

    Khiewvan, Benjapa [University of Texas MD Anderson Cancer Center, Department of Nuclear Medicine, Houston, TX (United States); Mahidol University, Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine Siriraj Hospital, Bangkok (Thailand); Macapinlac, Homer A.; Chuang, Hubert H. [University of Texas MD Anderson Cancer Center, Department of Nuclear Medicine, Houston, TX (United States); Lev, Dina; Al Sannaa, Ghadah [University of Texas MD Anderson Cancer Center, Department of Cancer Biology, Houston, TX (United States); McCutcheon, Ian E. [University of Texas MD Anderson Cancer Center, Department of Neurosurgery, Houston, TX (United States); Slopis, John M. [University of Texas MD Anderson Cancer Center, Department of Neuro-Oncology, Houston, TX (United States); Wei, Wei [University of Texas MD Anderson Cancer Center, Department of Biostatistics, Houston, TX (United States)

    2014-09-15

    Our objective was to determine how positron emission tomography (PET)/CT had been used in the clinical treatment of malignant peripheral nerve sheath tumor (MPNST) patients at The University of Texas MD Anderson Cancer Center. We reviewed a database of MPNST patients referred to MD Anderson Cancer Center during 1995-2011. We enrolled 47 patients who underwent PET/CT imaging. Disease stage was based on conventional imaging and PET/CT findings using National Comprehensive Cancer Network (NCCN) guidelines. Treatment strategies based on PET/CT and conventional imaging were determined by chart review. The maximum and mean standardized uptake values (SUV{sub max}, SUV{sub mean}), metabolic tumor volume (MTV), total lesion glycolysis (TLG), change in SUV{sub max}, change in MTV, and change in TLG were calculated from the PET/CT studies before and after treatment. Response prediction was based on imaging studies performed before and after therapy and categorized as positive or negative for residual tumor. Clinical outcome was determined from chart review. PET/CT was performed for staging in 16 patients, for restaging in 29 patients, and for surveillance in 2 patients. Of the patients, 88 % were correctly staged with PET/CT, whereas 75 % were correctly staged with conventional imaging. The sensitivity to detect local recurrence and distant metastasis at restaging was 100 and 100 % for PET/CT compared to 86 and 83 % for conventional imaging, respectively. PET/CT findings resulted in treatment changes in 31 % (5/16) and 14 % (4/29) of patients at staging and restaging, respectively. Recurrence, MTV, and TLG were prognostic factors for survival, whereas SUV{sub max} and SUV{sub mean} were not predictive. For 21 patients who had imaging studies performed both before and after treatment, PET/CT was better at predicting outcome (overall survival, progression-free survival) than conventional imaging. A decreasing SUV{sub max} ≥ 30 % and decrease in TLG and MTV were significant

  6. MR imaging in tumor invasion of the chest wall

    International Nuclear Information System (INIS)

    Bittner, R.C.; Lang, P.; Schorner, W.; Sander, B.; Weiss, T.; Loddenkemper, R.; Kaiser, D.; Felix, R.

    1989-01-01

    The authors have used MR imaging to study 22 patients who had intrathoracic, pleura-related malignancies and whose CT findings had suggested chest wall invasion. ECG-gated T1- and T2-weighted spin-echo sequences were used in all patients. Additionally, in 10 patients an ungated, multisection, gradient-echo sequence was used, which was repeated after intravenous administration of Gd-DTPA in five patients. Surgery confirmed chest wall invasion in 19 patients. CT showed tumor invasion only in 14 of these 19 patients. MR imaging showed high-signal-intensity lesion within chest wall and pleura in T2-weighted and Gd-DTPA-enhanced T1-weighted images as the typical pattern of chest wall invasion in all 19 patients. Two of the three patients with pleural inflammation and without chest wall invasion had high-signal-intensity pleural lesions, but none of these lesions were within the chest wall

  7. Impact of respiratory movement on the computed tomographic images of small lung tumors in three-dimensional (3D) radiotherapy

    International Nuclear Information System (INIS)

    Shimizu, Shinichi; Shirato, Hiroki; Kagei, Kenji; Nishioka, Takeshi; Bo Xo; Dosaka-Akita, Hirotoshi; Hashimoto, Seiko; Aoyama, Hidefumi; Tsuchiya, Kazuhiko; Miyasaka, Kazuo

    2000-01-01

    Purpose: Three-dimensional (3D) treatment planning has often been performed while patients breathe freely, under the assumption that the computed tomography (CT) images represent the average position of the tumor. We investigated the impact of respiratory movement on the free-breathing CT images of small lung tumors using sequential CT scanning at the same table position. Methods: Using a preparatory free-breathing CT scan, the patient's couch was fixed at the position where each tumor showed its maximum diameter on image. For 16 tumors, over 20 sequential CT images were taken every 2 s, with a 1-s acquisition time occurring during free breathing. For each tumor, the distance between the surface of the CT table and the posterior border of the tumor was measured to determine whether the edge of the tumor was sufficiently included in the planning target volume (PTV) during normal breathing. Results: In the sequential CT scanning, the tumor itself was not visible in the examination slice in 21% (75/357) of cases. There were statistically significant differences between lower lobe tumors (39.4%, 71/180) and upper lobe tumors (0%, 0/89) (p < 0.01) and between lower lobe tumors and middle lobe tumor (8.9%, 4/45) (p < 0.01) in the incidence of the disappearance of the tumor from the image. The mean difference between the maximum and minimum distances between the surface of the CT table and the posterior border of the tumor was 6.4 mm (range 2.1-24.4). Conclusion: Three-dimensional treatment planning for lung carcinoma would significantly underdose many lesions, especially those in the lower lobe. The excess 'safety margin' might call into question any additional benefit of 3D treatment. More work is required to determine how to control respiratory movement

  8. Evaluation of gross tumor size using CT, 18F-FDG PET, integrated 18F-FDG PET/CT and pathological analysis in non-small cell lung cancer

    International Nuclear Information System (INIS)

    Yu Huiming; Liu Yunfang; Hou Ming; Liu Jie; Li Xiaonan; Yu Jinming

    2009-01-01

    Purpose: The correlation of gross tumor sizes between combined 18 F-FDG PET/CT images and macroscopic surgical samples has not yet been studied in detail. In the present study, we compared CT, 18 F-FDG PET and combined 18 F-FDG PET/CT for the delineation of gross tumor volume (GTV) and validated the results through examination of the macroscopic surgical specimen. Methods: Fifty-two operable non-small cell lung cancer (NSCLC) patients had integrated 18 F-FDG PET/CT scans preoperatively and pathological examination post-operation. Four separate maximal tumor sizes at X (lateral direction), Y (ventro-dorsal direction) and Z (cranio-caudal direction) axis were measured on 18 F-FDG PET, CT, combined 18 F-FDG PET/CT and surgical specimen, respectively. Linear regression was calculated for each of the three imaging measurements versus pathological measurement. Results: No significant differences were observed among the tumor sizes measured by three images and pathological method. Compared with pathological measurement, CT size at X, Y, Z axis was larger, whereas combined 18 F-FDG PET/CT and 18 F-FDG PET size were smaller. Combined 18 F-FDG PET/CT size was more similar to the pathological size than that of 18 F-FDG PET or CT. Results of linear regressions showed that integrated 18 F-FDG PET/CT was the most accurate modality in measuring the size of cancer. Conclusions: 18 F-FDG PET/CT correlates more faithfully with pathological findings than 18 F-FDG PET or CT. Integrated 18 F-FDG PET/CT is an effective tool to define the target of GTV in radiotherapy.

  9. Image reconstruction design of industrial CT instrument for teaching

    International Nuclear Information System (INIS)

    Zou Yongning; Cai Yufang

    2009-01-01

    Industrial CT instrument for teaching is applied to teaching and study in field of physics and radiology major, image reconstruction is an important part of software on CT instrument. The paper expatiate on CT physical theory and first generation CT reconstruction algorithm, describe scan process of industrial CT instrument for teaching; analyze image artifact as result of displacement of rotation center, implement method of center displacement correcting, design and complete image reconstruction software, application shows that reconstructed image is very clear and qualitatively high. (authors)

  10. Clinical PET/CT imaging. Promises and misconceptions

    International Nuclear Information System (INIS)

    Czernin, J.; Auerbach, M.A.

    2005-01-01

    PET/CT is now established as the most important imaging tool in oncology. PET/CT stages and restages cancer with a higher accuracy than PET or CT alone. The sometimes irrational approach to combine state of the art PET with the highest end CT devices should give way to a more reasonable equipment design tailored towards the specific clinical indications in well-defined patient populations. The continuing success of molecular PET/CT now depends more upon advances in molecular imaging with the introduction of targeted imaging probes for individualized therapy approaches in cancer patients and less upon technological advances of imaging equipment. (orig.)

  11. Semi-automatic delineation using weighted CT-MRI registered images for radiotherapy of nasopharyngeal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Fitton, I. [European Georges Pompidou Hospital, Department of Radiology, 20 rue Leblanc, 75015, Paris (France); Cornelissen, S. A. P. [Image Sciences Institute, UMC, Department of Radiology, P.O. Box 85500, 3508 GA Utrecht (Netherlands); Duppen, J. C.; Rasch, C. R. N.; Herk, M. van [The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Department of Radiotherapy, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands); Steenbakkers, R. J. H. M. [University Medical Center Groningen, Department of Radiation Oncology, Hanzeplein 1, 9713 GZ Groningen (Netherlands); Peeters, S. T. H. [UZ Gasthuisberg, Herestraat 49, 3000 Leuven, Belgique (Belgium); Hoebers, F. J. P. [Maastricht University Medical Center, Department of Radiation Oncology (MAASTRO clinic), GROW School for Oncology and Development Biology Maastricht, 6229 ET Maastricht (Netherlands); Kaanders, J. H. A. M. [UMC St-Radboud, Department of Radiotherapy, Geert Grooteplein 32, 6525 GA Nijmegen (Netherlands); Nowak, P. J. C. M. [ERASMUS University Medical Center, Department of Radiation Oncology,Groene Hilledijk 301, 3075 EA Rotterdam (Netherlands)

    2011-08-15

    Purpose: To develop a delineation tool that refines physician-drawn contours of the gross tumor volume (GTV) in nasopharynx cancer, using combined pixel value information from x-ray computed tomography (CT) and magnetic resonance imaging (MRI) during delineation. Methods: Operator-guided delineation assisted by a so-called ''snake'' algorithm was applied on weighted CT-MRI registered images. The physician delineates a rough tumor contour that is continuously adjusted by the snake algorithm using the underlying image characteristics. The algorithm was evaluated on five nasopharyngeal cancer patients. Different linear weightings CT and MRI were tested as input for the snake algorithm and compared according to contrast and tumor to noise ratio (TNR). The semi-automatic delineation was compared with manual contouring by seven experienced radiation oncologists. Results: A good compromise for TNR and contrast was obtained by weighing CT twice as strong as MRI. The new algorithm did not notably reduce interobserver variability, it did however, reduce the average delineation time by 6 min per case. Conclusions: The authors developed a user-driven tool for delineation and correction based a snake algorithm and registered weighted CT image and MRI. The algorithm adds morphological information from CT during the delineation on MRI and accelerates the delineation task.

  12. CT/FMT dual-model imaging of breast cancer based on peptide-lipid nanoparticles

    Science.gov (United States)

    Xu, Guoqiang; Lin, Qiaoya; Lian, Lichao; Qian, Yuan; Lu, Lisen; Zhang, Zhihong

    2016-03-01

    Breast cancer is one of the most harmful cancers in human. Its early diagnosis is expected to improve the patients' survival rate. X-ray computed tomography (CT) has been widely used in tumor detection for obtaining three-dimentional information. Fluorescence Molecular Tomography (FMT) imaging combined with near-infrared fluorescent dyes provides a powerful tool for the acquisition of molecular biodistribution information in deep tissues. Thus, the combination of CT and FMT imaging modalities allows us to better differentiate diseased tissues from normal tissues. Here we developed a tumor-targeting nanoparticle for dual-modality imaging based on a biocompatible HDL-mimicking peptide-phospholipid scaffold (HPPS) nanocarrier. By incorporation of CT contrast agents (iodinated oil) and far-infrared fluorescent dyes (DiR-BOA) into the hydrophobic core of HPPS, we obtained the FMT and CT signals simultaneously. Increased accumulation of the nanoparticles in the tumor lesions was achieved through the effect of the tumor-targeting peptide on the surface of nanoparticle. It resulted in excellent contrast between lesions and normal tissues. Together, the abilities to sensitively separate the lesions from adjacent normal tissues with the aid of a FMT/CT dual-model imaging approach make the targeting nanoparticles a useful tool for the diagnostics of breast cancer.

  13. Magnetic resonance imaging for cardiac tumors

    International Nuclear Information System (INIS)

    Niwa, Koichiro; Tashima, Kazuyuki; Okajima, Yoshitomo; Nakajima, Hiromichi; Terai, Masaru; Nakajima, Hironori; Harada, Tsutomu; Ishida, Yoshikazu.

    1988-01-01

    We performed magnetic resonance imaging (MRI) in 4 patients with cardiac tumor (1 with rhabdomyoma, 1 with left atrial myxoma, and 2 with tumor of the left ventricular wall) for morphological evaluation of the tumor. ECG-gated MRI was performed by the spin echo imaging technique using a superconducting MRI system operating at 0.5 tesla. Spatial extension of the tumor was clearly demonstrated in all the patients. Gadolinium-DTPA (Gd-DTPA), was used in the 2 patients with tumor of the left ventricular myocardium to enhance the contrast, and allowed clear visualization of the tumor. These findings show the usefulness of MRI and MRI with Gd-DTPA for morphological evaluation of cardiac tumor. (author)

  14. FDG-PET/CT Imaging for Staging and Target Volume Delineation in Preoperative Conformal Radiotherapy of Rectal Cancer

    International Nuclear Information System (INIS)

    Bassi, Maria Chiara; Turri, Lucia; Sacchetti, Gianmauro; Loi, Gianfranco; Cannillo, Barbara; La Mattina, Pierdaniele; Brambilla, Marco; Inglese, Eugenio; Krengli, Marco

    2008-01-01

    Purpose: To investigate the potential impact of using 18 F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) on staging and target volume delineation for patients affected by rectal cancer and candidates for preoperative conformal radiotherapy. Methods and Materials: Twenty-five patients diagnosed with rectal cancer T3-4 N0-1 M0-1 and candidates for preoperative radiotherapy underwent PET/CT simulation after injection of 5.18 MBq/kg of FDG. Clinical stage was reassessed on the basis of FDG-PET/CT findings. The gross tumor volume (GTV) and the clinical target volume (CTV) were delineated first on CT and then on PET/CT images. The PET/CT-GTV and PET/CT-CTV were analyzed and compared with CT-GTV and CT-CTV, respectively. Results: In 4 of 25 cases (24%), PET/CT affected tumor staging or the treatment purpose. In 3 of 25 cases (12%) staged N0 M0, PET/CT showed FDG uptake in regional lymph nodes and in a case also in the liver. In a patient with a single liver metastasis PET/CT detected multiple lesions, changing the treatment intent from curative to palliative. The PET/CT-GTV and PET/CT-CTV were significantly greater than the CT-GTV (p = 0.00013) and CT-CTV (p = 0.00002), respectively. The mean difference between PET/CT-GTV and CT-GTV was 25.4% and between PET/CT-CTV and CT-CTV was 4.1%. Conclusions: Imaging with PET/CT for preoperative radiotherapy of rectal cancer may lead to a change in staging and target volume delineation. Stage variation was observed in 12% of cases and a change of treatment intent in 4%. The GTV and CTV changed significantly, with a mean increase in size of 25% and 4%, respectively

  15. 3D Interpolation Method for CT Images of the Lung

    Directory of Open Access Journals (Sweden)

    Noriaki Asada

    2003-06-01

    Full Text Available A 3-D image can be reconstructed from numerous CT images of the lung. The procedure reconstructs a solid from multiple cross section images, which are collected during pulsation of the heart. Thus the motion of the heart is a special factor that must be taken into consideration during reconstruction. The lung exhibits a repeating transformation synchronized to the beating of the heart as an elastic body. There are discontinuities among neighboring CT images due to the beating of the heart, if no special techniques are used in taking CT images. The 3-D heart image is reconstructed from numerous CT images in which both the heart and the lung are taken. Although the outline shape of the reconstructed 3-D heart is quite unnatural, the envelope of the 3-D unnatural heart is fit to the shape of the standard heart. The envelopes of the lung in the CT images are calculated after the section images of the best fitting standard heart are located at the same positions of the CT images. Thus the CT images are geometrically transformed to the optimal CT images fitting best to the standard heart. Since correct transformation of images is required, an Area oriented interpolation method proposed by us is used for interpolation of transformed images. An attempt to reconstruct a 3-D lung image by a series of such operations without discontinuity is shown. Additionally, the same geometrical transformation method to the original projection images is proposed as a more advanced method.

  16. A semiautomatic CT-based ensemble segmentation of lung tumors: comparison with oncologists' delineations and with the surgical specimen.

    Science.gov (United States)

    Rios Velazquez, Emmanuel; Aerts, Hugo J W L; Gu, Yuhua; Goldgof, Dmitry B; De Ruysscher, Dirk; Dekker, Andre; Korn, René; Gillies, Robert J; Lambin, Philippe

    2012-11-01

    To assess the clinical relevance of a semiautomatic CT-based ensemble segmentation method, by comparing it to pathology and to CT/PET manual delineations by five independent radiation oncologists in non-small cell lung cancer (NSCLC). For 20 NSCLC patients (stages Ib-IIIb) the primary tumor was delineated manually on CT/PET scans by five independent radiation oncologists and segmented using a CT based semi-automatic tool. Tumor volume and overlap fractions between manual and semiautomatic-segmented volumes were compared. All measurements were correlated with the maximal diameter on macroscopic examination of the surgical specimen. Imaging data are available on www.cancerdata.org. High overlap fractions were observed between the semi-automatically segmented volumes and the intersection (92.5±9.0, mean±SD) and union (94.2±6.8) of the manual delineations. No statistically significant differences in tumor volume were observed between the semiautomatic segmentation (71.4±83.2 cm(3), mean±SD) and manual delineations (81.9±94.1 cm(3); p=0.57). The maximal tumor diameter of the semiautomatic-segmented tumor correlated strongly with the macroscopic diameter of the primary tumor (r=0.96). Semiautomatic segmentation of the primary tumor on CT demonstrated high agreement with CT/PET manual delineations and strongly correlated with the macroscopic diameter considered as the "gold standard". This method may be used routinely in clinical practice and could be employed as a starting point for treatment planning, target definition in multi-center clinical trials or for high throughput data mining research. This method is particularly suitable for peripherally located tumors. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  17. Clinical study of the image fusion between CT and FDG-PET in the head and neck region

    International Nuclear Information System (INIS)

    Shozushima, Masanori; Moriguchi, Hitoshi; Shoji, Satoru; Sakamaki, Kimio; Ishikawa, Yoshihito; Kudo, Keigo; Satoh, Masanobu

    1999-01-01

    Image fusion using PET and CT from the head and neck region was performed with the use of external markers on 7 patients with squamous cell carcinoma. The purpose of this study was to examine a resultant error and the clinical usefulness of image fusion. Patients had primary lesions of the tongue, the maxillary gingiva or the maxillary sinus. All patients underwent PET with FDG and CT to detect tumor sites. Of these 7 patients, diagnostic images and the clinical observation found 6 cases of regional lymph node metastasis of the neck. To ensure the anatomical detail of the PET images, small radioactive markers were placed on the philtrum and below both earlobes. The PET image and CT image were then overlapped on a computer. The image fusion of PET and CT was successfully performed on all patients. The superposition error of this method was examined between the PET and CT images. The accuracy of fit measured as the mean distance between the PET and CT image was in the range of 2-5 mm. PET-CT superimposed images produced an increase in the localization of tumor FDG uptake and localized FDG uptake on the palatine tonsils. The marker system described here for the alignment of PET and CT images can be used on a routine basis without the invasive fixation of external markers, and also improve the management and follow up on patients with head and neck carcinoma. (author)

  18. Can the localization of primary colonic tumors be improved by staging CT without specific bowel preparation compared to optical colonoscopy?

    International Nuclear Information System (INIS)

    Feuerlein, Sebastian; Grimm, Lars J.; Davenport, Matthew S.; Haystead, Clare M.; Miller, Chad M.; Neville, Amy M.; Jaffe, Tracy A.

    2012-01-01

    Objectives: To investigate the ability of staging computed tomography (CT) without bowel preparation to accurately localize colonic tumors compared to optical colonoscopy. Methods: The local institutional review board approved this retrospective and HIPAA-compliant study. Forty-six patients with colonic adenocarcinoma, preoperative colonoscopy, and staging CT within 60 days of resection were included. Patients underwent contrast enhanced CT imaging without bowel preparation or oral contrast. The colon was divided into four segments with the operative reports used as the standard. Rectal and cecal cancers were excluded. CT scans were reviewed by 5 readers in a segmental binary fashion using a 5-point confidence scale in two sessions blinded and unblinded to the colonoscopy report. Results: At surgery 49 tumors were found in 46 patients. Readers detected 86.1%, 74.3%, and 66.9% of lesions with 92.0%, 94.1%, and 95.4% accuracy for confidence scores of ≥3, ≥4, and 5. CT interobserver agreement was good (κ = 0.82) for the unblinded and moderate (κ = 0.60) for the blinded read. Colonoscopic localization was only 78.7% accurate with 2 tumors undiscovered. Colonoscopic accuracy was low in the descending colon (57.1%) and the transverse colon (55.6%). Conclusions: Preoperative staging CT is more accurate than colonoscopy in the localization of colonic tumors

  19. Optimising imaging parameters in experimental spiral CT

    International Nuclear Information System (INIS)

    Tiitola, M.; Vehmas, T.; Kivisaari, R.P.; Kivisaari, L.

    1997-01-01

    Purpose: This in vitro study was conducted to analyse lesion detection and relative radiation exposure in different CT techniques. Material and Methods: We used a plastic phantom (12 x 8 x 2 cm) containing holes filled with air or fluid of varying densities to simulate lesions. This was imaged with Siemens Somatom Plus S and GE High Speed Advantage units. We varied table feeds (3 and 6 mm/s in Siemens and 3 and 4.5 mm/s in GE) and increments (2 mm and 4 mm) while keeping collimation at 3 mm. The SmartScan program of GE and the reformating algorithm of Siemens were also analysed. To evaluate the different methods, the phatnom lesions were counted by 3 observers. Radiation exposures associated with each technique were also measured. Results: The images reformatted to a coronal direction were significantly inferior (p<0.01) to those in other techniques. The use of SmartScan did not influence lesion detection, nor did changes in pitch or increment. Spiral and non-spiral techniques proved to be equal. Radiation exposure was lowest when a greater pitch or the SmartScan program was used. Conclusion: Radiation exposure in CT can be limited without significantly impairing the image quality by using low-dose techniques. Reformatting to a coronal direction should be used with care as it debases the image quality. (orig.)

  20. Diagnosis and evaluation of surveying examination by intracranial tumor in dogs CT; Diagnostico e avaliacao topografica de neoplasias intracranianas pelo exame de TC em caes

    Energy Technology Data Exchange (ETDEWEB)

    Romaldini, Andre Fonseca; Santos, Debora Rodrigues dos; Oliveira, Juliana Messias; Abreu, Felipe Andrei Suarez; Wallace, Verena; Pacheco, Eduardo Nelson da Silva, E-mail: andreromaldini@gmail.com [Hospital Santa Ines de Sao Paulo, Santana, SP (Brazil)

    2012-07-01

    The use of computed tomography (CT) revolutionized image diagnostic in veterinary medicine and currently can be considered one of the most useful tools for the imaging evaluation of intracranial tumor in dogs. Computed tomography of the brain in small animals allows visualization of intracranial tumor, compression of adjacent structures such as cerebral parenchyma, falx or lateral ventricles, and evaluate secondary hemorrhages and edema. The CT imaging provides essential information to indicate the surgical approach for a possible tumor resection or biopsy, including the correct location and boundaries structures involved, and also can be used to monitor the clinical treatment. However, only histopathological examination is able to confirm the final diagnosis. (author)

  1. Ga-67 tumor scan in malignant diffuse mesothelioma. Comparison with CT and pathological findings

    International Nuclear Information System (INIS)

    Yoshida, Shoji; Fukumoto, Mitsutaka; Motohara, Tomofumi; Oobayashi, Kayoko; Takada, Yoshiki; Tsubota, Noriaki; Sashikata, Terumasa

    1999-01-01

    Malignant diffuse mesothelioma is characterized by more difficult diagnosis and worse prognosis than other pleural tumors. In the Department of Thoracic Surgery, Hyogo Medical Center for Adults, 11 patients underwent panpleuropneumonectomy for this disease between January, 1988 and March, 1993. In 7 of these cases, Ga-67 scans were obtained before the operation. To clarify the factors affecting Ga-67 uptake in the pleural tumor, we compared Ga-67 uptake on the involved side of the thorax with CT and the pathological findings of the tumor. Regarding the use of Ga-67 scan imaging for the diagnosis of this disease, a number of related findings must be considered, such as an encircled wide Ga-67 uptake in the thickened pleural involvement and a diffuse slight Ga-67 uptake on the affected side with very slight involvement of the pleura. When the involved pleural thickness was over 6 mm, a definite correlation was found between the degree of Ga-67 uptake and the macroscopic thickness of mesothelioma in resected specimens. Thickness of the pleura on CT images demonstrates the real tumor thickness in the case of thickened involvement but in the case of thin involvement the real thickness of active mesothelioma could not be identified. No definite correlation was found between the degree of Ga-67 uptake and the histological type, or among microscopic findings, such as the extent of tumor parenchyma, interstitial volume and tumor vascularity. Our results suggest that the Ga-67 scan is very useful for revealing the extent of pleural involvement, especially when this involvement is more than 6 mm thick. (author)

  2. Ga-67 tumor scan in malignant diffuse mesothelioma. Comparison with CT and pathological findings

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Shoji; Fukumoto, Mitsutaka [Kochi Medical School, Nankoku (Japan); Motohara, Tomofumi; Oobayashi, Kayoko; Takada, Yoshiki; Tsubota, Noriaki; Sashikata, Terumasa

    1999-02-01

    Malignant diffuse mesothelioma is characterized by more difficult diagnosis and worse prognosis than other pleural tumors. In the Department of Thoracic Surgery, Hyogo Medical Center for Adults, 11 patients underwent panpleuropneumonectomy for this disease between January, 1988 and March, 1993. In 7 of these cases, Ga-67 scans were obtained before the operation. To clarify the factors affecting Ga-67 uptake in the pleural tumor, we compared Ga-67 uptake on the involved side of the thorax with CT and the pathological findings of the tumor. Regarding the use of Ga-67 scan imaging for the diagnosis of this disease, a number of related findings must be considered, such as an encircled wide Ga-67 uptake in the thickened pleural involvement and a diffuse slight Ga-67 uptake on the affected side with very slight involvement of the pleura. When the involved pleural thickness was over 6 mm, a definite correlation was found between the degree of Ga-67 uptake and the macroscopic thickness of mesothelioma in resected specimens. Thickness of the pleura on CT images demonstrates the real tumor thickness in the case of thickened involvement but in the case of thin involvement the real thickness of active mesothelioma could not be identified. No definite correlation was found between the degree of Ga-67 uptake and the histological type, or among microscopic findings, such as the extent of tumor parenchyma, interstitial volume and tumor vascularity. Our results suggest that the Ga-67 scan is very useful for revealing the extent of pleural involvement, especially when this involvement is more than 6 mm thick. (author)

  3. In-room CT techniques for image-guided radiation therapy

    International Nuclear Information System (INIS)

    Ma, C.-M. Charlie; Paskalev, Kamen M.S.

    2006-01-01

    Accurate patient setup and target localization are essential to advanced radiation therapy treatment. Significant improvement has been made recently with the development of image-guided radiation therapy, in which image guidance facilitates short treatment course and high dose per fraction radiotherapy, aiming at improving tumor control and quality of life. Many imaging modalities are being investigated, including x-ray computed tomography (CT), ultrasound imaging, positron emission tomography, magnetic resonant imaging, magnetic resonant spectroscopic imaging, and kV/MV imaging with flat panel detectors. These developments provide unique imaging techniques and methods for patient setup and target localization. Some of them are different; some are complementary. This paper reviews the currently available kV x-ray CT systems used in the radiation treatment room, with a focus on the CT-on-rails systems, which are diagnostic CT scanners moving on rails installed in the treatment room. We will describe the system hardware including configurations, specifications, operation principles, and functionality. We will review software development for image fusion, structure recognition, deformation correction, target localization, and alignment. Issues related to the clinical implementation of in-room CT techniques in routine procedures are discussed, including acceptance testing and quality assurance. Clinical applications of the in-room CT systems for patient setup, target localization, and adaptive therapy are also reviewed for advanced radiotherapy treatments

  4. Combined SPECT/CT and PET/CT for breast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Russo, Paolo [Università di Napoli Federico II, Dipartimento di Fisica, Via Cintia, Naples I-80126 (Italy); INFN Sezione di Napoli, Via Cintia, Naples I-80126 (Italy); Larobina, Michele [Istituto di Biostrutture e Bioimmagini, Consiglio Nazionale delle Ricerche, Via Tommaso De Amicis, 95, Naples I-80145 (Italy); Di Lillo, Francesca [Università di Napoli Federico II, Dipartimento di Fisica, Via Cintia, Naples I-80126 (Italy); INFN Sezione di Napoli, Via Cintia, Naples I-80126 (Italy); Del Vecchio, Silvana [Università di Napoli Federico II, Dipartimento di Scienze Biomediche Avanzate, Via Pansini, 5, Naples I-80131 (Italy); Mettivier, Giovanni, E-mail: mettivier@na.infn.it [Università di Napoli Federico II, Dipartimento di Fisica, Via Cintia, Naples I-80126 (Italy); INFN Sezione di Napoli, Via Cintia, Naples I-80126 (Italy)

    2016-02-11

    In the field of nuclear medicine imaging, breast imaging for cancer diagnosis is still mainly based on 2D imaging techniques. Three-dimensional tomographic imaging with whole-body PET or SPECT scanners, when used for imaging the breast, has performance limits in terms of spatial resolution and sensitivity, which can be overcome only with a dedicated instrumentation. However, only few hybrid imaging systems for PET/CT or SPECT/CT dedicated to the breast have been developed in the last decade, providing complementary functional and anatomical information on normal breast tissue and lesions. These systems are still under development and clinical trials on just few patients have been reported; no commercial dedicated breast PET/CT or SPECT/CT is available. This paper reviews combined dedicated breast PET/CT and SPECT/CT scanners described in the recent literature, with focus on their technological aspects.

  5. Variations in tumor size and position due to irregular breathing in 4D-CT: A simulation study

    International Nuclear Information System (INIS)

    Sarker, Joyatee; Chu, Alan; Mui, Kit; Wolfgang, John A.; Hirsch, Ariel E.; Chen, George T. Y.; Sharp, Gregory C.

    2010-01-01

    Purpose: To estimate the position and volume errors in 4D-CT caused by irregular breathing. Methods: A virtual 4D-CT scanner was designed to reproduce axial mode scans with retrospective resorting. This virtual scanner creates an artificial spherical tumor based on the specifications of the user, and recreates images that might be produced by a 4D-CT scanner using a patient breathing waveform. 155 respiratory waveforms of patients were used to test the variability of 4D-CT scans. Each breathing waveform was normalized and scaled to 1, 2, and 3 cm peak-to-peak motion, and artificial tumors with 2 and 4 cm radius were simulated for each scaled waveform. The center of mass and volume of resorted 4D-CT images were calculated and compared to the expected values of center of mass and volume for the artificial tumor. Intrasubject variability was investigated by running the virtual scanner over different subintervals of each patient's breathing waveform. Results: The average error in the center of mass location of an artificial tumor was less than 2 mm standard deviation for 2 cm motion. The corresponding average error in volume was less than 4%. In the worst-case scenarios, a center of mass error of 1.0 cm standard deviation and volume errors of 30%-60% at inhale were found. Systematic errors were observed in a subset of patients due to irregular breathing, and these errors were more pronounced when the tumor volume is smaller. Conclusions: Irregular breathing during 4D-CT simulation causes systematic errors in volume and center of mass measurements. These errors are small but depend on the tumor size, motion amplitude, and degree of breathing irregularity.

  6. Preparing diagnostic 3D images for image registration with planning CT images

    International Nuclear Information System (INIS)

    Tracton, Gregg S.; Miller, Elizabeth P.; Rosenman, Julian; Chang, Sha X.; Sailer, Scott; Boxwala, Azaz; Chaney, Edward L.

    1997-01-01

    Purpose: Pre-radiotherapy (pre-RT) tomographic images acquired for diagnostic purposes often contain important tumor and/or normal tissue information which is poorly defined or absent in planning CT images. Our two years of clinical experience has shown that computer-assisted 3D registration of pre-RT images with planning CT images often plays an indispensable role in accurate treatment volume definition. Often the only available format of the diagnostic images is film from which the original 3D digital data must be reconstructed. In addition, any digital data, whether reconstructed or not, must be put into a form suitable for incorporation into the treatment planning system. The purpose of this investigation was to identify all problems that must be overcome before this data is suitable for clinical use. Materials and Methods: In the past two years we have 3D-reconstructed 300 diagnostic images from film and digital sources. As a problem was discovered we built a software tool to correct it. In time we collected a large set of such tools and found that they must be applied in a specific order to achieve the correct reconstruction. Finally, a toolkit (ediScan) was built that made all these tools available in the proper manner via a pleasant yet efficient mouse-based user interface. Results: Problems we discovered included different magnifications, shifted display centers, non-parallel image planes, image planes not perpendicular to the long axis of the table-top (shearing), irregularly spaced scans, non contiguous scan volumes, multiple slices per film, different orientations for slice axes (e.g. left-right reversal), slices printed at window settings corresponding to tissues of interest for diagnostic purposes, and printing artifacts. We have learned that the specific steps to correct these problems, in order of application, are: Also, we found that fast feedback and large image capacity (at least 2000 x 2000 12-bit pixels) are essential for practical application

  7. Imaging benign pathology and variants with uptake in 68ga-Dotatate PET/CT studies

    International Nuclear Information System (INIS)

    Servente, L.; Bianco, C.; Gigirey, V.; Alonso, O.

    2017-01-01

    Purpose: To evaluate the physiological, anatomical variants and benign lesions in positron emission computed tomography (PET/CT) studies with 68Ga-DOTATATE.Materials and methods: We retrospectively reviewed PET/CT reports scanned with 68Ga-DOTATATE and selected those that contained words in the report related to anatomical, physiological variants and benign tumors. The degree of 68Ga-DOTATATE uptake was evaluated qualitatively and quantitatively by measuring the standarized uptake max value (SUVmax value). The anatomical location, SUVmax value and morphological CT image findings were recorded. All cases had clinical and imaging follow-up. Results: From a total of 772 PET/CT reports, 28 patients were obtained with 33 benign variants or tumors, 14 females and 14 males with a median age of 63 years. Uptake patterns were classified into four groups: anatomic and physiological variants (15), dependent on osteoblastic activity (4), dependent on inflammatory activity (10) and non-neuro-endocrine benign tumors (4).Discussion: Somatostatin receptors are overexpressed not only in the neuroendocrine system but also in other tissues. Physiological, anatomical variants and benign tumors expressing these receptors may be misleading. In the present work the frequency of this finding is 5.1%.Conclusion: Physiological variants and benign lesions (tumor and inflammatory) can accumulate 68Ga-DOTATATE since their tissues can express somatostatin receptors. The semiologic analysis of the tomographic component of this hybrid method enhances the diagnostic efficacy, optimizing PET/CT study performance. (authors) [es

  8. Prognostic value of tumor necrosis at CT in diffuse large B-cell lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Hugo J.A., E-mail: h.j.a.adams@gmail.com [Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Utrecht (Netherlands); Klerk, John M.H. de [Department of Nuclear Medicine, Meander Medical Center, Amersfoort (Netherlands); Fijnheer, Rob [Department of Hematology, Meander Medical Center, Amersfoort (Netherlands); Dubois, Stefan V. [Department of Pathology, Meander Medical Center, Amersfoort (Netherlands); Nievelstein, Rutger A.J.; Kwee, Thomas C. [Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Utrecht (Netherlands)

    2015-03-15

    Highlights: •CT is compulsory for staging newly diagnosed DLBCL. •Approximately 13.7% of DLBCL patients have tumor necrosis at CT. •Tumor necrosis status at CT is not associated with any NCCN-IPI factor. •Patients with tumor necrosis at CT have a significantly worse outcome. -- Abstract: Objective: To determine the prognostic value of tumor necrosis at computed tomography (CT) in newly diagnosed diffuse large B-cell lymphoma (DLBCL). Materials and methods: This retrospective study included 51 patients with newly diagnosed DLBCL who had undergone both unenhanced and intravenous contrast-enhanced CT before R-CHOP (rituximab, cyclophosphamide, hydroxydaunorubicin, oncovin and prednisolone) chemo-immunotherapy. Presence of tumor necrosis was visually and quantitatively assessed at CT. Associations between tumor necrosis status at CT and the National Comprehensive Cancer Network (NCCN) International Prognostic Index (IPI) factors were assessed. Cox regression analysis was used to determine the prognostic impact of NCCN-IPI scores and tumor necrosis status at CT. Results: There were no correlations between tumor necrosis status at CT and the NCCN-IPI factors categorized age (ρ = −0.042, P = 0.765), categorized lactate dehydrogenase (LDH) ratio (ρ = 0.201, P = 0.156), extranodal disease in major organs (φ = −0.245, P = 0.083), Ann Arbor stage III/IV disease (φ = −0.208, P = 0.141), and Eastern Cooperative Oncology Group (ECOG) performance status (φ = 0.015, P = 0.914). In the multivariate Cox proportional hazards model, only tumor necrosis status at CT was an independent predictive factor of progression-free survival (P = 0.003) and overall survival (P = 0.004). Conclusion: The findings of this study indicate the prognostic potential of tumor necrosis at CT in newly diagnosed DLBCL.

  9. Splenosis Mimicking Relapse of a Neuroendocrine Tumor at Gallium-68-DOTATOC PET/CT

    International Nuclear Information System (INIS)

    Treglia, Giorgio; Luca, Giovanella; Barbara, Muoio; Carmelo, Caldarella

    2014-01-01

    A 48-year-old female patient underwent splenopancreasectomy for a 4-cm pancreatic neuroendocrine tumor (pNET), grade G2, located in the pancreatic tail. One year after surgery, the patient presented an increased serum level of the tumor marker chromogranin A (value: 160 U/l). Therefore, she underwent somatostatin receptor PET/CT using gallium-68-DOTATOC for restaging. This imaging method showed a focal area of increased radiopharmaceutical uptake corresponding to a 2.5-cm nodule located in the left superior abdomen near a clip from the previous surgery, suggesting a possible relapse of pNET. Based on this PET/CT finding, the patient underwent ultrasonography-guided core biopsy of this nodule. Histology did not reveal findings suggestive of pNET but identified spleen tissue most likely caused by splenosis accidentally seeded at the previous operation. It is likely that the increased serum level of the tumor marker chromogranin A was due to the chronic proton-pump inhibitors use. Somatostatin receptor PET/CT is an accurate imaging method for staging and restaging pNET, presenting high sensitivity and specificity in this setting. Nevertheless, possible sources of false-negative and -positive findings with this method should be taken into account. Inflammatory lesions represent the most frequent causes of false-positive findings for pNET at somatostatin receptor imaging because inflammatory cellsmay overexpress somatostatin receptors on their cell surface. In our case, we showed that splenosis may represent a possible cause of false-positive findings for pNET relapse due to the physiological uptake of somatostatin analogs by the spleen tissue

  10. CT images of an anthropomorphic and anthropometric male pelvis phantom

    Energy Technology Data Exchange (ETDEWEB)

    Matos, Andrea S.D. de; Campos, Tarcisio P.R. de, E-mail: campos@nuclear.ufmg.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-graduacao em Ciencias e Tecnicas Nucleares

    2009-07-01

    Actually, among of the most often neoplasm types are the cancer of prostate, bladder and intestine. The incidence of the intestine neoplasm in Brazil is at fourth among the most frequent tumors of the male sex, barely close to the stomach, lung and prostate incidences. Phantoms are objects used as simulators for investigating ionizing radiation transport on humans, especially during radiation therapy or radiological diagnostic. The purpose of this work is the achievement of a set of computerized tomography (CT)