Abstract:
RATIONALE AND OBJECTIVES:Simultaneous single-photon emission computed tomography (SPECT) neuroimaging with both technetium-99m (99mTc) hexamethylpropyleneamine oxime (HMPAO) and iodine-123 (123I) N-isopropyl-iodoamphetamine is a recently introduced method with potential for assessing activation phenomena in the brain. However, there is limited information on the accuracy of the technique for detecting focal cortical sites of neuroactivation. We determined, in vitro, what levels of activation could be detected as a function of the size of the activated region. METHODS:A Lucite brain phantom was filled with both 123I and 99mTc so as to simulate both a nonactivated state (123I) along with focal sites of activation (99mTc). Simulated activations ranged from 0 to 18% in volumes of 7, 14, 20, and 27 cm3. Imaging was performed with a triple-detector gamma camera using a 10% symmetric window at 140 keV and 10% asymmetric window around 159 keV. No correction was made for gamma cross-talk. To determine whether a simulated activation was "detected," the 99mTc: 123I count ratios in the activated regions were compared by t test with ratios in nonactivated regions of similar volume. Detection sensitivities also were calculated as the fraction of the activated 99mTc: 123I ratios that were greater than the mean + 2 standard deviations of the corresponding nonactivated ratios. RESULTS:All sites of simulated activations of 10% or greater were detected. The detection sensitivity was 100% (95% confidence interval, 90-100%) for the two largest chambers with simulated activations of 13-18%. Activations in the 3-6% range, in the same-sized chambers, were detected with a limited sensitivity (67% with a confidence interval of 45-84%). In the 14-cm3 chamber, simulated activations in the 13-18% range were detected with 90% sensitivity (confidence interval, 74-98%). In general, the detection sensitivity was greater for larger chambers and higher levels of simulated activation. CONCLUSION:We conclude that the dual-radioisotope technique using triple-detector SPECT systems and low-energy all-purpose (LEAP) collimators should be highly reliable for identifying focal brain activations above 13% that cover at least 14 cm3 of brain cortex. Smaller, less intense sites of activation will be detected with reduced frequency. These conclusions are based on our assessment of only the physical parameters involved in this methodology and other factors (e.g., the possibility that the relation between cerebral radiotracer concentration and regional cerebral blood flow) may affect the results obtained with patients.
journal_name
Acad Radioljournal_title
Academic radiologyauthors
Bushnell DL,Madsen M,Cremer S,Kahn D,Kirchner PTdoi
10.1016/s1076-6332(05)80242-9subject
Has Abstractpub_date
1995-01-01 00:00:00pages
26-32issue
1eissn
1076-6332issn
1878-4046journal_volume
2pub_type
杂志文章abstract::Breast density has been shown to be a strong, independent risk factor for breast cancer. Unfortunately, mammography is less accurate on dense breast tissue compared to fattier breast tissue. Multiple studies suggest a solution to this by demonstrating the ability of supplemental screening ultrasound to detect addition...
journal_title:Academic radiology
pub_type: 杂志文章,评审
doi:10.1016/j.acra.2016.05.017
更新日期:2016-12-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The goal of this prospective, interinstitutional study was to compare the long-term instructional effectiveness of a pediatric multimedia textbook (MMTB) to that of a standard lecture and a printed textbook. MATERIALS AND METHODS:A randomized cohort of 89 3rd-year medical students from two ins...
journal_title:Academic radiology
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1016/s1076-6332(97)80074-8
更新日期:1997-11-01 00:00:00
abstract:PURPOSE:This investigation is part of a prospective National Institutes of Health-funded study evaluating three different methods for estimating the optimal length for placement of a new nasogastric (NG) tube. Abdomen radiographs were required to determine the location of the tube tip. Our objective was to analyze diff...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2012.02.007
更新日期:2012-06-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:This study aimed to measure apparent diffusion coefficient (ADC) in Chinese patients with newly diagnosed multiple myeloma by whole-body diffusion-weighted magnetic resonance imaging (WB-DWI MRI) and assess the diagnostic accuracy of ADC in the discrimination of deep response to induction chemo...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2017.12.008
更新日期:2018-07-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:We sought to identify factors associated with high levels of external research funding in order to provide departments with information that may help them increase their external research funding. MATERIALS AND METHODS:National Institutes of Health (NIH) data on grants were analyzed to identif...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2006.09.052
更新日期:2006-12-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:I developed a volume estimation technique for the crescentic volume of the right ventricle (RV) of the heart. A geometric model was desired to avoid the lengthy data collection and reduction required by Simpson's rule. METHODS:An ellipsoidal shell model was developed that requires only simple ...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/s1076-6332(12)80006-7
更新日期:1994-12-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The authors compared magnetic resonance (MR) image quality obtained from 3- and 1-mm-thick sections in the depiction of the temporomandibular joint (TMJ) and its adjacent structures. MATERIALS AND METHODS:Eight TMJ specimens from four adult cadaver heads were depicted with MR imaging. Both 3- ...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/S1076-6332(99)80116-0
更新日期:1999-11-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:This study was performed to determine physical characteristics of areas on chest radiographs that are suspicious but not definitive for the presence of a pulmonary nodule and the characteristics of areas that contain an obvious nodule. MATERIALS AND METHODS:Two groups of patients were identifi...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/s1076-6332(98)80297-3
更新日期:1998-09-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Photodynamic therapy (PDT) is a promising strategy for treating cancer. PDT involves three components: a photosensitizer (PS) drug, a specific wavelength of drug-activating light, and oxygen. A challenge in PDT is the unknown biodistribution of the PS in the target tissue. In this preliminary s...
journal_title:Academic radiology
pub_type: 杂志文章,评审
doi:10.1016/j.acra.2013.11.009
更新日期:2014-02-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:To retrospectively analyze the significance of 3.0-T contrast-enhanced (CE) magnetic resonance angiography (MRA) with calf compression in the lower limbs of diabetic patients with peripheral vascular disease. MATERIALS AND METHODS:Sixty-one type 2 diabetes patients underwent both MRA and digit...
journal_title:Academic radiology
pub_type: 杂志文章,随机对照试验
doi:10.1016/j.acra.2011.01.013
更新日期:2011-06-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The addition of digital breast tomosynthesis (DBT) to digital screening mammography (DM) has been shown to decrease recall rates and improve cancer detection rates, but there is a lack of data regarding the impact of DBT on rates of short-term follow-up. We assessed possible changes in performa...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2016.10.001
更新日期:2017-03-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The development of curriculum guidelines for radiology residency has been found to be favored by 80% of program directors (PDs) nationwide. I surveyed PDs to develop a consensus of opinion concerning minimum training requirements in the subspecialty rotations. METHODS:A survey developed by mem...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/s1076-6332(96)80013-4
更新日期:1996-06-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Despite recent advances in the treatment of high-grade gliomas, overall survival (OS) remains poor, which underlines the importance of searching for and determining prognostic imaging biomarkers. The purpose of our retrospective study was to correlate patient survival with relative cerebral blo...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2012.11.011
更新日期:2013-04-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The purpose of our study was to evaluate magnetic resonance (MR) artifacts related to breast tissue markers in breast imaging procedures. MATERIALS AND METHODS:In this bicentric prospective ex vivo study 10 different commercially available markers were measured in self-made breast phantoms. Br...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2019.12.006
更新日期:2021-01-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Dimeric nonionic iodinated contrast has a lower osmolality than monomeric nonionic iodinated contrast but is available at lower iodine concentrations. Less dilution of intravascular fluid by influx from the extravascular space is proposed to occur with decreasing osmolality. The purpose of this...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2005.01.015
更新日期:2005-05-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Balloon dilatation is a mechanical form of controlled injury used to alleviate vascular stenoses. Several factors influence successful angioplasty. Few mechanical models exist to illustrate the physical principles of balloon dilatation. METHODS:We used mechanical analysis of membrane stresses,...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/s1076-6332(05)80340-x
更新日期:1995-05-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:To evaluate whether a computer-aided diagnosis (CADx) technique can accurately classify breast calcifications in full-field digital mammograms (FFDMs) as malignant or benign. The computer technique was developed previously on screen-film mammograms (SFMs) in which individual calcifications were...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2006.12.012
更新日期:2007-03-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Histological subtypes of lung cancers are critical for clinical treatment decision. In this study, we attempt to use 3D deep learning and radiomics methods to automatically distinguish lung adenocarcinomas (ADC), squamous cell carcinomas (SCC), and small cell lung cancers (SCLC) respectively on...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2020.06.010
更新日期:2020-07-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Early-stage diagnosis of Parkinson's disease (PD) is essential in making decisions related to treatment and prognosis. However, there is no specific diagnostic test for the diagnosis of PD. The aim of this study was to evaluate the role of texture analysis (TA) of magnetic resonance images in d...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2011.06.007
更新日期:2011-10-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Blooming artifact from calcified plaques often renders measurement of stenosis impossible on coronary computed tomographic angiography (CTA). We sought to evaluate the impact of modifying window level on reducing blooming artifact, and its impact on stenosis quantification. MATERIALS AND METHO...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2014.02.016
更新日期:2014-06-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Epicardial adipose tissue (EAT), pericardial adipose tissue (PAT), and subcutaneous adipose tissue (SAT) are mediators of metabolic risk and may be involved in the pathogenesis of coronary artery disease. The aim of this study was to investigate the association of visceral and subcutaneous fat ...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2010.08.017
更新日期:2010-12-01 00:00:00
abstract::Imaging screening examinations are growing in their indications and volume to identify conditions at an early, treatable stage. The Radiology Research Alliance's 'Role of Imaging in Health Screening' Task Force provides a review of imaging-based screening rationale, economics, and describes established guidelines by v...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2020.03.038
更新日期:2020-05-11 00:00:00
abstract:RATIONALE AND OBJECTIVES:Mammographic breast density is an important and widely accepted risk factor for breast cancer. A statement about breast density in the mammographic report is becoming a requirement in many States. However, there is significant inter-observer variation between radiologists in their interpretatio...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2011.07.011
更新日期:2011-11-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The authors studied the role of the endothelium and associated endothelial pathways in contrast material-induced renal vasoconstriction. MATERIALS AND METHODS:Isometric contractions in human and rabbit renal artery rings with intact and denuded endothelium were stimulated with phenylephrine an...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/s1076-6332(97)80254-1
更新日期:1997-12-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:A critical element in determining biologic behavior of pulmonary nodules is volume and temporal volume change. We evaluate variability in nodule volume among readers and measuring methods. MATERIALS AND METHODS:55 small (<2 cm) lung nodules were measured in long- and short-axis dimensions inde...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2005.04.009
更新日期:2005-08-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The authors performed this study to determine if bronchial wall thickening is present in children with moderate to severe asthma during periods free from clinical bronchoconstriction. MATERIALS AND METHODS:The authors obtained low (radiation) dose thin-section computed tomographic (CT) scans i...
journal_title:Academic radiology
pub_type: 杂志文章,多中心研究
doi:10.1016/S1076-6332(03)80535-4
更新日期:2001-03-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Multireader imaging trials often use a factorial design, in which study patients undergo testing with all imaging modalities and readers interpret the results of all tests for all patients. A drawback of this design is the large number of interpretations required of each reader. Split-plot desi...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2012.09.012
更新日期:2012-12-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:To report the detection rate for lung cancers in computed tomography (CT) screening in Japanese adults, and to analyze differences in the appearance of the cancers in non-smokers versus smokers. MATERIALS AND METHODS:Subjects consisted of 7,847 Japanese adults who received low-dose CT screenin...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/s1076-6332(03)00150-8
更新日期:2003-09-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The aim of this study was to investigate the subjective similarity for pairs of images with various abnormal patterns of diffuse interstitial lung disease on thin-section computed tomography by experienced radiologists to explore a basis for selecting similar images to assist radiologists' inte...
journal_title:Academic radiology
pub_type: 杂志文章
doi:10.1016/j.acra.2008.10.016
更新日期:2009-04-01 00:00:00
abstract::The three missions of academic radiology compete with one another for time and funding. Revenue for the clinical mission often subsidizes education and research. Given the internal and external drivers/pressures on health care and, more particularly, on academic health centers, the current model is unsustainable. Tren...
journal_title:Academic radiology
pub_type: 杂志文章,评审
doi:10.1016/j.acra.2013.04.003
更新日期:2013-10-01 00:00:00