Abstract:
OBJECTIVE:The objective of this study was to develop and validate a novel noise insertion method that can accurately simulate lower-dose images from existing standard-dose computed tomography (CT) data. METHODS:The noise insertion method incorporates the effects of the bowtie filter, automatic exposure control, and electronic noise. We validated this tool using both phantom and patient studies. The phantom study compared simulated lower-dose images with the actually acquired lower-dose images. The patient studies included 105 pediatric and 24 adult CT body examinations. RESULTS:The noise level in the simulated images was within 3.2% of the actual lower-dose images in phantom experiments. Noise power spectrum also demonstrated excellent agreement. For the patient examinations, a mean difference of noise level between 2.0% and 9.7% was observed for simulated dose levels between 75% and 30% of the original dose. CONCLUSIONS:An accurate technique for simulating lower-dose CT images was developed and validated, which can be used to retrospectively optimize CT protocols.
journal_name
J Comput Assist Tomogrjournal_title
Journal of computer assisted tomographyauthors
Yu L,Shiung M,Jondal D,McCollough CHdoi
10.1097/RCT.0b013e318258e891subject
Has Abstractpub_date
2012-07-01 00:00:00pages
477-87issue
4eissn
0363-8715issn
1532-3145pii
00004728-201207000-00020journal_volume
36pub_type
杂志文章abstract:OBJECTIVE:To evaluate the distal extent and attenuation of bowel opacification achieved after administration of a single low volume dose of oral contrast 2 hours before computed tomographic colonography (CTC) after incomplete optical colonoscopy. METHODS:This retrospective study included 144 patients undergoing CTC af...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章,多中心研究
doi:10.1097/RCT.0b013e3181f5a610
更新日期:2011-01-01 00:00:00
abstract::We present three cases of glioblastoma with CSF dissemination that contrast-enhanced fluid-attenuated inversion recovery MRI was sensitive enough to detect compared with contrast-enhanced T1-weighted MRI. An autopsy was performed on one patient, and its histologic findings proved the existence of CSF dissemination. ...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-200111000-00020
更新日期:2001-11-01 00:00:00
abstract:OBJECTIVE:The purpose of this article is to report computed tomography demonstration of medial bowing of the lamina papyracea in 5 patients after internal ethmoidectomy. METHODS:We identified 5 patients who had apparent medial bowing of the lamina papyracea after functional endoscopic sinus surgery (FESS) and who had ...
journal_title:Journal of computer assisted tomography
pub_type: 临床试验,杂志文章
doi:10.1097/RCT.0b013e31816c82da
更新日期:2009-01-01 00:00:00
abstract:OBJECTIVE:The purpose of this study was to investigate the early manifestation of hypervascular hepatocellular carcinomas by means of evaluating the "nodule-in-nodule" hepatic lesions depicted on dynamic computed tomography. METHODS:For 26 lesions with hypervascular foci in nonhypervascular nodules in 23 patients with...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/RCT.0b013e3181670fa3
更新日期:2009-01-01 00:00:00
abstract:PURPOSE:The purpose of this work was to define the characteristic MR features of colorectal mucinous carcinomas and to correlate the mucin pool with the signal intensity of this tumor. METHOD:MRI of 12 cases of pathologically proven colorectal carcinoma containing mucin was evaluated. We analyzed the signal intensity ...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-199903000-00021
更新日期:1999-03-01 00:00:00
abstract:PURPOSE:Our goal was to validate linear and nonlinear intersubject image registration using an automated method (AIR 3.0) based on voxel intensity. METHOD:PET and MRI data from 22 normal subjects were registered to corresponding averaged PET or MRI brain atlases using several specific linear and nonlinear spatial tran...
journal_title:Journal of computer assisted tomography
pub_type: 临床试验,杂志文章
doi:10.1097/00004728-199801000-00028
更新日期:1998-01-01 00:00:00
abstract::The effect of hemodialysis on the CT absorption value of the liver was examined in 14 hemodialysis patients. In the high ultrafiltration group [10 patients with a weight loss of -1.7 to -3.5 (2.9 +/- 0.6) kg], the hepatic CT absorption value increased from 49.6 +/- 7.0 to 58.7 +/- 8.7 Hounsfield units (p less than 0.0...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-198408000-00021
更新日期:1984-08-01 00:00:00
abstract:PURPOSE:To compare the efficacy and patient tolerance of iohexol and meglumine sodium diatrizoate as oral contrast agents for computed tomography (CT). SUBJECTS AND METHODS:One hundred patients were randomly assigned to drink 1000 mL of either meglumine sodium diatrizoate or iohexol 350 before their abdominopelvic CT ...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章,随机对照试验
doi:10.1097/RCT.0b013e3182058e76
更新日期:2011-03-01 00:00:00
abstract::A 31-year-old woman with an aneurysmal bone cyst of the L1 vertebral body proved by biopsy and studied by plain lumbar spine roentgenography, radionuclide studies, myelography, and CT is presented. The unusual location of involvement of the vertebral body alone and the difficulty in differential diagnosis between aneu...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-198412000-00031
更新日期:1984-12-01 00:00:00
abstract::Seventy selected cases were reviewed retrospectively to assess the normal Gd-DTPA enhanced MR appearance of the cervical anterior epidural venous plexus. This structure can enhance quite markedly and has a somewhat variable appearance on MR imaging but we believe that it can be differentiated from pathological enhance...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-199209000-00017
更新日期:1992-09-01 00:00:00
abstract:PURPOSE:A new nonrigid registration method, designed to reduce the effect of movement artifact in subtraction images from breast MR, is compared with existing rigid and affine registration methods. METHOD:Nonrigid registration was compared with rigid and affine registration methods and unregistered images using 54 gad...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-199909000-00031
更新日期:1999-09-01 00:00:00
abstract:OBJECTIVE:The purpose of this study was to determine whether computed tomography (CT) angiography with machine learning (ML) can be used to predict the rapid growth of abdominal aortic aneurysm (AAA). MATERIALS AND METHODS:This retrospective study was approved by our institutional review board. Fifty consecutive patie...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/RCT.0000000000000958
更新日期:2020-01-01 00:00:00
abstract::Benign hepatic neoplasms constitute a heterogeneous group of neoplasms with characteristic histology and variable tumor biology. Based on the cell of origin, benign hepatic neoplasms are classified into epithelial, nonepithelial, and miscellaneous categories according to the 2000 World Health Organization classificati...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章,评审
doi:10.1097/RCT.0b013e31815a5748
更新日期:2008-11-01 00:00:00
abstract:INTRODUCTION:Stereotactic ablative radiotherapy (SABR) offers a curative treatment for lung cancer in patients who are marginal surgical candidates. However, unlike traditional surgery the lung cancer remains in place after treatment. Thus, imaging follow-up for evaluation of recurrence is of paramount importance. MAT...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/RCT.0000000000000262
更新日期:2015-09-01 00:00:00
abstract:OBJECTIVE:To assess the prognostic value of computed tomography (CT) in hyperacute middle cerebral artery (MCA) infarcts. METHODS:The CT features, total CT score, and National Institutes of Health Stroke Scale (NIHSS) score were correlated with the 30-day mortality in 16 patients with a hyperacute MCA infarct. RESULT...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/01.rct.0000136456.25506.c3
更新日期:2004-09-01 00:00:00
abstract::Thirty patients with suspected or known chronic aortic dissection were imaged with magnetic resonance (MR), CT, and angiography. Five of these patients had previously undergone surgical repair of the ascending aorta for a type A dissection. Magnetic resonance demonstrated an intimal flap and a double lumen in 25 cases...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-198711000-00009
更新日期:1987-11-01 00:00:00
abstract:OBJECTIVE:Optic nerve glioma is a common finding in patients with neurofibromatosis type 1 (NF-1). Although dural ectasia of the optic nerve is encountered rarely, it has to be considered in the differential diagnosis. MATERIALS AND METHODS:Three patients affected by NF-1 were examined sequentially by CT and MRI. RES...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-199409000-00009
更新日期:1994-09-01 00:00:00
abstract::Pulmonary vein stenosis is one of the frequent complications after radiofrequency ablation for atrial fibrillation. MRI plays an important role in depicting the pathoanatomic structure of the pulmonary veins, and measuring the blood flow velocity in the pulmonary veins before and after therapy, and is superior to tran...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-200101000-00006
更新日期:2001-01-01 00:00:00
abstract::Forty-two patients with hepatocellular carcinoma (HCC) were examined by magnetic resonance (MR) imaging. The presence of tumor was suggested in 41 of 42 cases by a high-intensity area on T2 weighted spin-echo (SE) images with a repetition time (TR) of 1.6 s. Specific findings of HCC such as the presence of a capsule, ...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-198611000-00012
更新日期:1986-11-01 00:00:00
abstract::We present clinical and chest computed tomography (CT) features of 5 cases of pediatric patients with 2019 novel coronavirus. Two patients had fever and dry cough, whereas the rest of 3 patients were asymptomatic. Three patients had unilateral ground glass opacities with or without consolidation in the subpleural regi...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/RCT.0000000000001023
更新日期:2020-05-01 00:00:00
abstract:OBJECTIVE:Our goal was to analyze the sources of nonuniform image intensity of two surface coil configurations used on a General Electric 1.5 T Signa scanner and to correct the major source. MATERIALS AND METHODS:Correction of receive coil nonuniform sensitivity is achieved using division by images of a uniform phanto...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-199411000-00033
更新日期:1994-11-01 00:00:00
abstract:OBJECTIVE:We aim to determine the relationship between leukoaraiosis and carotid artery stenosis. METHODS:Carotid-cerebral multislice computed tomography angiographies of 194 patients (mean age, 63.5 years) were retrospectively evaluated. Presence and severity of leukoaraiosis and carotid artery stenosis were compared...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/RCT.0b013e318284604e
更新日期:2013-05-01 00:00:00
abstract::A case of a 26-year-old woman with decreasing vision in her right eye, diplopia, headache, and galactorrhea is presented. Both CT and MR studies showed a large sphenoid fibroosseous lesion that had a ground glass appearance on CT and low-to-intermediate proton density and low T2-weighted and low T1-weighted signal int...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-199305000-00032
更新日期:1993-05-01 00:00:00
abstract:OBJECTIVE:The objective of this study was to investigate the image quality and diagnostic performance of model-based iterative reconstruction (MBIR) for hepatic vessel evaluation on low-tube-voltage (100 kilovolt [peak]) liver computed tomography (CT) for living donors. METHODS:Fifty-one liver donor candidates (low-ki...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/RCT.0b013e3182ab6cc0
更新日期:2014-05-01 00:00:00
abstract::Four patients with intracranial glioependymal cysts were evaluated in our institution in the last 7 years. All underwent surgical drainage and biopsy of the cyst wall. Cranial CT revealed a uniformly hypodense lesion with no contrast enhancement in all cases. Magnetic resonance imaging studies revealed a well defined ...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:
更新日期:1992-11-01 00:00:00
abstract::The goal of neuro-oncologic surgery is to maximize tumor resection while preserving vital brain functions. Identification of the relation between the tumor and adjacent functional cortical areas as well as efferent subcortical white matter tracts is important for preservation of function. Combined diffusion tensor ima...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-200407000-00019
更新日期:2004-07-01 00:00:00
abstract::We describe a case of disruption of the blood-brain barrier (BBB) by nonionic, low osmolality contrast medium after abdominal angiography. One plausible explanation of this event is that acute hypertension during angiography may have increased the BBB permeability, allowing the contrast medium to leak across it. ...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-198909000-00027
更新日期:1989-09-01 00:00:00
abstract::Construction of a new ultrafast scanner system suitable for dynamic computed tomography is now under consideration, with development soon to begin. This system will be characterized by an electronically controlled X-ray generator with wide angle double diffraction, which will permit transverse axial images to be taken...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/00004728-197710000-00017
更新日期:1977-10-01 00:00:00
abstract:OBJECTIVE:To capture 3D shape variation of the levator ani during straining with open access MR imaging. METHODS:Optimal scan-planning based on statistical shape modeling is developed for recovering the entire 3D structure of the levator ani from a limited number of 2D imaging planes. Statistical shape modeling ensure...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章
doi:10.1097/01.rct.0000155076.42784.ed
更新日期:2005-03-01 00:00:00
abstract::Several classification systems for neuroendocrine tumors (NETs) exist, which use variable terminology and criteria for grading and staging. This variability in terminology can cause confusion and difficulty in recognizing which tumors are, in fact, members of this heterogeneous group of malignancies. The largest group...
journal_title:Journal of computer assisted tomography
pub_type: 杂志文章,评审
doi:10.1097/RCT.0000000000000140
更新日期:2014-11-01 00:00:00