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Conventional Imaging (conventional + imaging)

Distribution by Scientific Domains

Medical Sciences	75%

Selected Abstracts

Role of magnetic resonance imaging in the diagnosis and single-stage surgical resection of invasive lobular carcinoma of the breast,

BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 10 2002
K. Munot
Background: Conventional imaging with mammography and ultrasonography has a low sensitivity for diagnosis and a tendency to underestimate the extent of invasive lobular carcinoma (ILC) of the breast. The aim was to determine whether magnetic resonance imaging (MRI) had any advantages for the characterization of ILC. Methods: Twenty patients with histologically proven ILC underwent preoperative imaging with MRI. MRI was performed to aid detection of malignancy in six patients with a clinically suspicious presentation but normal or indeterminate imaging on mammography and ultrasonography. In 14 patients MRI was performed to determine tumour extent. Results: MRI accurately identified malignancy in five of six patients with normal or indeterminate conventional imaging. In seven of 14 patients in whom MRI was performed to determine tumour extent, it provided significant additional information. These included four patients in whom conventional imaging grossly underestimated tumour size, two patients in whom MRI identified an unsuspected contralateral breast tumour and one patient in whom MRI predicted tumour invasion of the pectoral muscle. The correlation between tumour size on histological examination was better with MRI (r = 0·967) than with mammography (r = 0·663) and ultrasonography (r = 0·673). Conclusion: MRI can provide considerable additional information in the detection and characterization of ILC. © 2002 British Journal of Surgery Society Ltd [source]

Evaluation of Left Ventricular Systolic and Diastolic Global Function: Peak Positive and Negative Myocardial Velocity Gradients in M-Mode Doppler Tissue Imaging

ECHOCARDIOGRAPHY, Issue 1 2002
Yoshiki Ueno M.D.
Objectives: To evaluate a new indicator of left ventricular global function: Myocardial velocity gradient (MVG) M-mode Doppler tissue imaging (DTI). Background: MVG is a new indicator of regional left ventricular function and global left ventricular diastolic function. However, it is unclear whether MVG also is an indicator of left ventricular global function in comparison with invasive indices. Methods: We performed conventional imaging and M-mode DTI in 85 subjects and calculated MVG at the posterior wall. We obtained satisfactory images in 65 subjects, who we divided into three groups: Noninvasive study group, invasive study group, and hemodialysis group. The noninvasive study group was divided into three subgroups (a younger normal subgroup, an older normal subgroup, and a cardiomyopathy subgroup), and MVG was compared with indices of conventional imaging. In the invasive study group, we compared MVG and indices of conventional imaging with hemodynamic data (peak positive and negative dp/dt, and the time constant T) using a high fidelity micromanometer-tipped catheter. In the hemodialysis group, we compared indices before hemodialysis with those after hemodialysis. Results: Peak positive MVG correlated well with peak positive dp/dt (r = 0.79), and this did not change with hemodialysis (P = 0.87). Peak negative MVG also correlated well with peak positive dp/dt and the time constant T (r = 0.88 and r = 0.80), and this did not change with hemodialysis (P = 0.97). Conclusions: Peak positive and negative MVG are sensitive and load-insensitive indicators of left ventricular function. [source]

Exploring the relationship between white matter and gray matter damage in early primary progressive multiple sclerosis: An in vivo study with TBSS and VBM

HUMAN BRAIN MAPPING, Issue 9 2009
Benedetta Bodini
Abstract We investigated the relationship between the damage occurring in the brain normal-appearing white matter (NAWM) and in the gray matter (GM) in patients with early Primary Progressive multiple sclerosis (PPMS), using Tract-Based Spatial Statistics (TBSS) and an optimized voxel-based morphometry (VBM) approach. Thirty-five patients with early PPMS underwent diffusion tensor and conventional imaging and were clinically assessed. TBSS and VBM were employed to localize regions of lower fractional anisotropy (FA) and lower GM volume in patients compared with controls. Areas of anatomical and quantitative correlation between NAWM and GM damage were detected. Multiple regression analyses were performed to investigate whether NAWM FA or GM volume of regions correlated with clinical scores independently from the other and from age and gender. In patients, we found 11 brain regions that showed an anatomical correspondence between reduced NAWM FA and GM atrophy; of these, four showed a quantitative correlation (i.e., the right sensory motor region with the adjacent corticospinal tract, the left and right thalamus with the corresponding thalamic radiations and the left insula with the adjacent WM). Either the NAWM FA or the GM volume in each of these regions correlated with disability. These results demonstrate a link between the pathological processes occurring in the NAWM and in the GM in PPMS in specific, clinically relevant brain areas. Longitudinal studies will determine whether the GM atrophy precedes or follows the NAWM damage. The methodology that we described may be useful to investigate other neurological disorders affecting both the WM and the GM. Hum Brain Mapp 2009. © 2009 Wiley-Liss, Inc. [source]

Experimental design comparison of studies evaluating doxorubicin nanoparticles in breast cancer therapy

HUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 3 2008
Farman A. Moayed
Background The unique properties of nanoparticles (NP) qualify these colloidal systems for a wide range of medical applications, including diagnosis and treatment. Particularly in cancer therapy, NP have significantly enhanced the potential of conventional imaging, radiotherapy, and chemotherapy and, consequently, offered new avenues for early interventions. So far, breast cancer has been one of the most studied cancer types with NP research, which can benefit the occupational breast cancer for the increasing number of women in the labor force in industry. Objectives The objective of this study is to compare the experimental designs of preclinical studies that assessed the effect of doxorubicin NP (DOX-NP) on the estrogen-dependent MCF-7 breast cancer cell line using a recently established quantitative Experimental Appraisal Instrument (ExpAI). Methods A systematic review of research articles published between August 2004 and August 2005 on NP and breast cancer treatment with doxorubicin was performed using various online databases and indexes available through the University of Cincinnati. Restrictive inclusion and exclusion criteria were defined leading to selection of four relevant articles that used comparable experimental designs. Critical appraisal of those studies was performed by five independent assessors using the ExpAI version 2.0 and the results were summarized in a table of evidence. Results The study design in the selected articles was either between groups or mixed, with sample sizes varying from n = 3,6, and the evaluation of the effect of DOX-NP either in vitro or in vivo. The cytotoxic drug doxorubicin was the input variable in all studies, whereas different end points such as pharmacokinetic parameters, cytotoxicity surrogates (e.g., growth inhibition, mitochondrial activity), and quantitative analysis of messenger RNA were used as output variables. Conclusions Although the articles assessed in this article were preclinical experimental studies, the results showed that doxorubicin NP drugs can be used effectively to enhance the delivery process in MCF-7 breast cancer cells by increasing the circulation time and targeting the tumor tissues. Considering the rising number of women in the labor force and the risk of occupational breast cancer, it can be concluded that DOX-NP may potentially be used as an effective anticancer drug on humans, but further research and studies are required to understand how DOX-NP drugs might react in the human body before using it on breast cancer patients. © 2008 Wiley Periodicals, Inc. [source]

Hyperspectral imaging combined with principal component analysis for bruise damage detection on white mushrooms (Agaricus bisporus)

JOURNAL OF CHEMOMETRICS, Issue 3-4 2008
A. A. Gowen
Abstract Hyperspectral imaging (HSI) combines conventional imaging and spectroscopy to simultaneously acquire both spatial and spectral information from an object. This technology has recently emerged as a powerful process analytical tool for rapid, non-contact and non-destructive food analysis. In this study, the potential application of HSI for damage detection on the caps of white mushrooms (Agaricus bisporus) was investigated. Mushrooms were damaged by controlled vibration to simulate damage caused by transportation. Hyperspectral images were obtained using a pushbroom line-scanning HSI instrument, operating in the wavelength range of 400,1000,nm with spectroscopic resolution of 5,nm. The effective resolution of the CCD detector was 580,×,580,pixels by 12 bits. Two data reduction methods were investigated: in the first, principal component analysis (PCA) was applied to the hypercube of each sample, and the second PC (PC 2) scores image was used for identification of bruise-damaged regions on the mushroom surface; in the second method PCA was applied to a dataset comprising of average spectra from regions normal and bruise-damaged tissue. In this case it was observed that normal and bruised tissue were separable along the resultant first principal component (PC 1) axis. Multiplying the PC 1 eigenvector by the hypercube data allowed reduction of the hypercube to a 2-D image, which showed maximal contrast between normal and bruise-damaged tissue. The second method performed better than the first when applied to a set of independent mushroom samples. The results from this study could be used for the development of a non-destructive monitoring system for rapid detection of damaged mushrooms on the processing line. Copyright © 2008 John Wiley & Sons, Ltd. [source]

A case of bronchopulmonary carcinoid tumor: The role of octreotide scanning in localization of an ectopic source of ACTH

JOURNAL OF HOSPITAL MEDICINE, Issue 5 2006
P. D. Bhatia BSc
Abstract BACKGROUND Bronchopulmonary carcinoids are neuroendocrine tumors. They can present with Cushing's syndrome secondary to ectopic adrenocorticotropic hormone (ACTH) secretion. Curative resection is possible only after adequate localization of the ectopic source. OBJECTIVE To describe a case that illustrates the role of octreotide scanning in the management of a bronchopulmonary carcinoid. RESULTS The use of preoperative and postoperative octreotide scanning aided in performing a limited resection, thereby preserving the lung parenchyma. CONCLUSIONS We propose that octreotide scanning can be a very important and informative test in the management of carcinoid tumors. In situations when conventional imaging is not conclusive, octreotide scanning may be of help in determining the source of ectopic ACTH syndrome. Journal of Hospital Medicine 2006;1:312,316. © 2006 Society of Hospital Medicine. [source]

Impact of 18F-fluorodeoxyglucose positron emission tomography in the staging and treatment response assessment of extra-pulmonary small-cell cancer

JOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 2 2010
DL Gregory
Summary The aim of this study was to retrospectively evaluate the value of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in extrapulmonary small-cell cancer (EPSCC). Patients with EPSCC who underwent PET for staging or response assessment between 1996 and 2007 were identified from a database. Patient records were reviewed. PET-based, and conventional staging and restaging results were compared. The binary staging classification of limited disease (LD) versus extensive disease (ED) was used. Patients with LD had tumours that could be encompassed within a tolerable radiation therapy (RT) volume. Of 33 eligible patients, 12 had staging PET scans, 11 had restaging scans and 10 had both. All known gross disease sites were FDG-avid. PET and conventional stage groupings were concordant in 21 of 22 cases. One patient was appropriately upstaged from LD to ED by PET. PET detected additional disease sites, without causing upstaging in three further patients. Restaging PET scans identified previously unrecognised persistent or progressive disease in 4 of 21 cases. In four further cases, persistent FDG uptake after treatment was either false positive (n = 2) or of uncertain (n = 2) aetiology. PPV was 100% for staging and 82% for restaging. In 8 of 43 imaging episodes (19%), PET appropriately influenced management in five cases by changing treatment intent from radical to palliative, and in three cases by altering the RT volume. PET has incremental value compared to conventional imaging for staging EPSCC, and may also be useful for restaging after therapy. PET influenced patient management in 19% of 43 imaging episodes. [source]

Positive contrast imaging of iron oxide nanoparticles with susceptibility-weighted imaging

MAGNETIC RESONANCE IN MEDICINE, Issue 4 2010
Frank Eibofner
Abstract Superparamagnetic iron oxide particles can be utilized to label cells for immune cell and stem cell therapy. The labeled cells cause significant field distortions induced in their vicinity, which can be detected with magnetic resonance imaging (MRI). In conventional imaging, the signal voids arising from the field distortions lead to negative contrast, which is not desirable, as detection of the cells can be masked by native low signal tissue. In this work, a new method for visualizing magnetically labeled cells with positive contrast is proposed and described. The technique presented is based on the susceptibility-weighted imaging (SWI) post-processing algorithm. Phase images from gradient-echo sequences are evaluated pixel by pixel, and a mask is created with values ranging from 0 to 1, depending on the phase value of the pixel. The magnitude image is then multiplied by the mask. With an appropriate mask function, positive contrast in the vicinity of the labeled cells is created. The feasibility of this technique is proved using an agar phantom containing superparamagnetic iron oxide particles,labeled cells and an ex vivo bovine liver. The results show high potential for detecting even small labeled cell concentrations in structurally inhomogeneous tissue types. Magn Reson Med, 2010. © 2010 Wiley-Liss, Inc. [source]

Tissue Doppler echocardiographic assessment of cardiac function in children with bronchial asthma

PEDIATRICS INTERNATIONAL, Issue 6 2007
CENAP ZEYBEK
Abstract Background: The aim of the present study was to evaluate the role of tissue Doppler echocardiography in assessment of ventricular function in pediatric patients with bronchial asthma (BA). Patients and methods: Fifty-one pediatric patients with BA and 30 age- and sex-matched healthy subjects were studied. BA patients were divided into two groups: mild BA (n = 33) and moderate to severe BA (n = 18). All subjects were examined on conventional and tissue Doppler echocardiography, and 44 patients had pulmonary function tests on spirometry within 1 week of echocardiographic examination. Results: Conventional echocardiographic parameters were all similar in mild asthmatic patients and control subjects. Tricuspid E velocity, E/A ratio and isovolumetric relaxation time (IVRT) in moderate and severe cases differed significantly from mild cases and control subjects. E,, A,, E,/A, ratio and IVRT of the lateral tricuspid annulus, and IVRT of the medial and lateral mitral annuli were different between mild cases and control subjects. E, velocity and IVRT of the lateral tricuspid annulus and IVRT of the medial and lateral mitral annuli were also different between mild cases and moderate to severe cases. Pulmonary function tests correlated well with E,, E,/A, and IVRT of lateral tricuspid annulus. Conclusion: Patients with BA have subclinical right ventricular diastolic dysfunction even in the early stages. The severity of the functional impairment is parallel with the severity of the disease. Tissue Doppler echocardiography has a greater predictive value than conventional imaging, and is useful for evaluating ventricular function in patients with BA. [source]

111Indium Pentetreotide Imaging in the Evaluation of Head and Neck Tumors

THE LARYNGOSCOPE, Issue 10 2005
David Myssiorek MD
Abstract Objectives/Hypothesis: Peptide receptor imaging with 111Indium pentetreotide is useful in the diagnosis of diffuse neuroendocrine system tumors (DNEST) of the head and neck. Uses of 111Indium pentetreotide scintigraphy include tumor and metastases detection, familial tumor screening, and surveillance for recurrence. Using target to background ratios (TBR) could generate a comparative scale for these tumors. Study Design: A retrospective study evaluated the size, TBR, conventional imaging, and outcomes of patients imaged with 111Indium pentetreotide scintigraphy for suspected head and neck DNEST. Methods: Patients with head and neck tumors imaged by 111Indium pentetreotide scintigraphy during a nine-year period were reviewed. Data analyzed were age, sex, scintigraphy, pathology, and conventional radiology. Tumor data included dimension, multiplicity, metastases, and tumor and brain counts. Results: Fifty-three patients underwent 58 scans. The sensitivity and specificity were 93% and 92%. Several different DNEST were successfully evaluated, including familial paragangliomas and multiple paragangliomas. TBRs were variable depending on type of DNEST. Conclusions:111Indium pentetreotide scintigraphy is accurate in determining the presence of paragangliomas, carcinoid tumors, esthesioneuroblastomas, small cell neuroendocrine tumors, andmetastases. It is an excellent surveillance tool. Screening patients for familial paragangliomas can be accomplished. No reliable comparative scale to distinguish amongst the various DNEST could be developed using TBR. [source]

The role of indirect radionuclide cystography during the acute phase of pyelonephritis in young women

BJU INTERNATIONAL, Issue 4 2005
Jehonathan H. Pinthus
Authors from Israel have investigated the use of dynamic renal scans in young female patients with acute pyelonephritis, combined with indirect radionuclide cystography. They found that using these techniques may avoid up to half of the delayed voiding cysto-urethrograms, preventing the related inconvenience and cost. OBJECTIVE To review our experience using dynamic 99mTc-diethylenetriamine penta-acetic acid renal scintigraphy combined with indirect radionuclide cystography (IRC) in the acute phase of pyelonephritis, as a possible alternative to the conventional imaging, as investigating acute pyelonephritis usually includes imaging the upper urinary tract during the acute phase, to exclude obstruction, and delayed voiding cysto-urethrography (VCUG) when underlying vesico-ureteric reflux (VUR) is suspected. PATIENTS AND METHODS Between 1997 and 1999, 47 young women (median age 22 years, range 18,37) were hospitalized for acute pyelonephritis. The combined study was used during the acute phase of the disease, usually within 24 h of hospitalization. The principle of IRC is based on the reappearance of radioactivity in the ureters or kidneys after previously detecting renal clearance of an intravenously injected radioisotope. The increase in radioactivity over the ureters or kidneys indicates VUR. The subsequent follow-up included VCUG, after recovery and at least 6 weeks after discharge. RESULTS Overall, 47 patients had early IRC studies; obstruction of the urinary tract during the acute phase of the disease was excluded in all. In 13 (28%) of the patients early IRC studies showed VUR involving 21 upper tract units. The renal parenchymal scan was impaired in 17 (36%) patients, and six of these 17 also had detectable concomitant reflux on IRC. Overall, 24 IRC studies (51%) were considered positive, showing VUR, renal parenchymal pathology or both; 23 (49%) were normal. Follow-up VCUG was used in 32 patients (68%); only three (9%) detected VUR. All of the patients with VUR on follow-up VCUG had also had an abnormal early IRC study, showing either reflux (two) or findings suggestive of pathological renal parenchyma (one). CONCLUSIONS In addition to the well-established role of renal scintigraphy in excluding obstruction of the collecting system, early IRC is characterized by high sensitivity and accurate negative predictive value for detecting VUR. It can therefore be used to screen adults presenting with acute pyelonephritis for the presence of VUR. Patients with an abnormal IRC require follow-up VCUG after complete recovery, while those with a negative study may be managed expectantly, with no further radiological evaluation. This proposed strategy may avoid up to half of the delayed VCUG studies, preclude the related inconvenience, and substantially reduce the costs. [source]