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1.
BMC Musculoskelet Disord ; 22(1): 138, 2021 Feb 04.
Article in English | MEDLINE | ID: mdl-33541314

ABSTRACT

BACKGROUND: Although telehealth is becoming more popular for delivery of care for individuals with musculoskeletal pain, to our knowledge telehealth has not been used to manage Achilles tendinopathy. This research aimed to explore the experience of participants and physiotherapists with gym-based exercise interventions for Achilles tendinopathy monitored via videoconference. METHODS: A qualitative, interpretive description design was performed using semi-structured interviews (8 participants) and a focus group (7 physiotherapists). Participants and physiotherapists were interviewed about their experiences of the use of telehealth during a gym-based exercise intervention incorporating different calf load parameters for Achilles tendinopathy. We employed an inductive thematic analysis approach to analyse the data. RESULTS: Three themes identified from both participants and physiotherapists included i) acceptability of telehealth; ii) enablers to adherence with telehealth; and iii) barriers to adherence with telehealth. Two extra themes arose from participants regarding adherence with gym-based exercise, including enablers to adherence with the exercise intervention, and barriers to adherence with the exercise intervention. Both participants and physiotherapists expressed overall satisfaction and acceptability of telehealth monitoring of gym-based exercise. CONCLUSION: Gym-based exercise intervention for Achilles tendinopathy involving weekly telehealth monitoring was acceptable to both participants and physiotherapists. Potential enablers and barriers were identified that may improve adherence to this type of intervention.


Subject(s)
Achilles Tendon , Physical Therapists , Telemedicine , Tendinopathy , Exercise , Exercise Therapy , Humans , Tendinopathy/therapy
2.
Am J Transplant ; 17(1): 296-299, 2017 01.
Article in English | MEDLINE | ID: mdl-28029734

ABSTRACT

November 11, 2016/65(44);1234-1237. What is already known about this topic? Candida auris is an emerging pathogenic fungus that has been reported from at least a dozen countries on four continents during 2009-2015. The organism is difficult to identify using traditional biochemical methods, some isolates have been found to be resistant to all three major classes of antifungal medications, and C. auris has caused health care-associated outbreaks. What is added by this report? This is the first description of C. auris cases in the United States. C. auris appears to have emerged in the United States only in the last few years, and U.S. isolates are related to isolates from South America and South Asia. Evidence from U.S. case investigations suggests likely transmission of the organism occurred in health care settings. What are the implications for public health practice? It is important that U.S. laboratories accurately identify C. auris and for health care facilities to implement recommended infection control practices to prevent the spread of C. auris. Local and state health departments and CDC should be notified of possible cases of C. auris and of isolates of C. haemulonii and Candida spp. that cannot be identified after routine testing.


Subject(s)
Candida/isolation & purification , Candidiasis/diagnosis , Candidiasis/microbiology , Drug Resistance, Multiple, Fungal , Antifungal Agents/therapeutic use , Candida/drug effects , Candidiasis/drug therapy , Communicable Diseases, Emerging , Global Health , Humans , Prognosis , Risk Factors , Time Factors , United States
3.
Disabil Rehabil ; 44(14): 3686-3693, 2022 07.
Article in English | MEDLINE | ID: mdl-33577359

ABSTRACT

BACKGROUND: Rotator cuff related shoulder pain (RCRSP) is a common and disabling shoulder condition and surgical management is becoming more common. The rates and costs of surgical interventions have been on the rise. Understanding decision-making related to surgery and providing adequate information to people with RCRSP may improve patient-centred care and potentially reduce rates of surgery. OBJECTIVES: To explore the decision-making processors of people who have undertaken surgery for RCRSP. DESIGN: An in-depth thematic analysis. METHOD: Interviews were conducted with patients from Melbourne who had had surgical management for RCRSP. Data were analysed using an inductive thematic approach. RESULTS: Fifteen participants were recruited. Six key themes emerged: (1) Needing to get it done: "It was necessary to remedy the dire situation"; (2) Non-surgical treatment experience:" I knew that I'd done all I could"; (3) Mechanical problem:" Physio's not going to repair a torn tendon"; (4) Trust in medical professionals "If they told me that I needed to swallow a thousand spiders, I would have done it."; (5) Varied information sources "Dr Google played a big part in it"; (6) Organisational barriers "It was absolutely useless, my insurance." CONCLUSION: Surgery appears to be commonly precipitated by unremitted severe symptoms and failed non-surgical treatment. While there was strong trust in highly trained surgeons, decision to undergo surgery also drew on questionable pathoanatomical beliefs and instances of inadequate patient information about treatment choices and risks that may be addressed by adopting a more patient-centred care approach.IMPLICATIONS FOR REHABILITATIONUnderstanding decision-making related to surgery and providing adequate information to people with rotator cuff related shoulder pain may improve patient-centred care.Surgery appears to be commonly precipitated by unremitted severe symptoms and failed non-surgical treatment.Decision to undergo surgery sometimes drew on questionable pathoanatomical beliefs.There was strong trust in highly trained surgeons but there were instances of inadequate patient information about treatment choices and risks.


Subject(s)
Rotator Cuff Injuries , Rotator Cuff , Humans , Rotator Cuff/surgery , Rotator Cuff Injuries/surgery , Shoulder , Shoulder Pain/etiology , Shoulder Pain/surgery
4.
Magn Reson Med ; 66(2): 564-73, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21394767

ABSTRACT

The aim of this study was to design a computer algorithm to assess the extent of cardiac edema from triple inversion recovery MR images of the human left ventricular myocardium. Twenty-one patients presenting with acute myocardial infarction were scanned within 48 h of the onset of symptoms. Eight patients were scanned a second time, 4 weeks after the initial event. Myocardial edema was detected in 27 of 29 studies using visual contour-based manual segmentation. A reference standard, created from the segmentations of three raters by voxel-wise majority voting, was compared to the edema mass estimates obtained using a newly developed computer algorithm. At baseline (n=20), the reference standard yielded an edema mass of 16.4±15.0 g (mean±SD) and the computer algorithm edema mass was 16.4±12.6 g. At follow-up (n=7), the reference standard edema mass was 7.1±4.4 g compared to 16.3±7.7 g at baseline. Computer algorithm estimates showed the same pattern of change with 5.7±5.7 g at follow-up compared to 20.8±13.8 g at baseline. Although there was a significant degree of discrepancy between reference standard and computer algorithm estimates of edema mass in individual patients, their overall agreement was good, with intraclass correlation coefficient ICC(3, 1)=0.753.


Subject(s)
Algorithms , Edema/diagnosis , Edema/etiology , Image Interpretation, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Myocardial Infarction/complications , Myocardial Infarction/diagnosis , Adult , Aged , Female , Humans , Image Enhancement/methods , Male , Reproducibility of Results , Sensitivity and Specificity
5.
J Cell Biol ; 72(2): 302-13, 1977 Feb.
Article in English | MEDLINE | ID: mdl-833200

ABSTRACT

The intracellular location of a cytochrome P-450-dependent monoterpene hydroxylase from the higher plant, Catharanthus roseus, has been investigated. By differential and sucrose density gradient centrifugation, utilizing marker enzymes and electron microscopy, the monooxygenase was demonstrated to be associated with vesicles having a membrane thickness of 40-60 nm. The vesicles could be distinguished from endoplasmic reticulum, Golgi apparatus, mitochondria, and plasma membrane and were found in light membrane fractions containing provacuoles. Most definitive results were obtained when seedlings were ground in the presence of sand and in a medium containing sorbitol. Upon subjection of the 20,000-g pellet preparation to linear sucrose density gradient centrifugation, a threefold enrichment in hydroxylase activity was afforded in a yellow band having vesicles varying in size from 0.1 to 0.8 mum in diam and having a density of 1.09 to 1.10 g/cm3. Since the monooxygenase has been implicated in indole alkaloid biosynthesis in this plant, the data suggest the compartmentalization of at least a part of this pathway.


Subject(s)
Cytochrome P-450 Enzyme System , Mixed Function Oxygenases/analysis , Organoids/enzymology , Plants/enzymology , Vacuoles/enzymology , Alcohols , Centrifugation, Density Gradient , Plants/ultrastructure
6.
Clin Otolaryngol ; 34(5): 460-6, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19793279

ABSTRACT

OBJECTIVES: Optical coherence tomography, an imaging modality using near-infrared light, produces cross-sectional tissue images with a lateral pixel resolution of 10 microm. However, normative data is first needed on epithelial thickness for lesion characterisation, and, to date, little exists. The purpose of our study is to measure normal laryngeal epithelial thickness by in vivo optical coherence tomography, and compare these values to those obtained from fixed ex-vivo laryngectomy specimens. DESIGN AND SETTING: Prospective at a single medical center in California, United States. PARTICIPANTS: A total of 116 patients undergoing operative endoscopy. MAIN OUTCOME MEASURES: Optical coherence tomography images of clinically normal laryngeal subsites were selected. Calibrated measurements of epithelial thickness at various laryngeal subsites were recorded. Measurements of epithelial thickness from corresponding areas were obtained using optical micrometry on histologically normal regions of 15 total laryngectomy specimens. Descriptive statistics were performed. RESULTS: Mean epithelial optical coherence tomography thicknesses were: true vocal cords (81 microm), false vocal cords (78 microm), subglottis (61 microm), aryepiglottic folds (111 microm), laryngeal epiglottis (116 microm) and lingual epiglottis (170 microm). Epithelial thicknesses in fixed tissues were: true vocal cords (103 microm), false vocal cords (79 microm), aryepiglottic folds (205 microm) subglottis (61 microm), laryngeal epiglottis (38 microm) and lingual epiglottis (130 microm). CONCLUSIONS: Optical coherence tomography does not have the artifacts associated with conventional histologic techniques. The inevitable development of office-based optical coherence tomography devices will increase the precision of laryngeal measurements and contribute to the clinical application of this technology in diagnosing laryngeal disease.


Subject(s)
Laryngeal Neoplasms/pathology , Larynx/pathology , Aged , Female , Humans , Laryngeal Neoplasms/surgery , Laryngectomy , Laryngoscopy , Larynx/surgery , Male , Middle Aged , Tomography, Optical Coherence
7.
Radiography (Lond) ; 24(4): 283-288, 2018 11.
Article in English | MEDLINE | ID: mdl-30292495

ABSTRACT

INTRODUCTION: To measure the range of T1 values of synovitis using three Tesla (3 T) magnetic resonance imaging (MRI) in patients with osteoarthritis to assess the potential of T1 mapping for identifying synovitis from other features in the knee on unenhanced magnetic resonance scans. METHODS: After receiving institutional ethical approval, 83 patients who met the American College of Rheumatology criteria for diagnosis of osteoarthritis of the knee were scanned using a 3 T Magnetic Resonance Imaging scanner. T1 maps were calculated from spoiled gradient echo images acquired with five different flip angles of 5°-25°. Mean values for the T1 measurements were calculated and compared to existing data from the published literature for anatomical and pathological structures of the knee. RESULTS: T1 values recorded in patients suffering from osteoarthritis demonstrated that T1 values for synovitis (confirmed on gadolinium enhanced images) fall in a narrow range (849-1277 ms, mean 1005 ms SD 91) delineating this from other structures of the knee such as muscle (T1 value range 1305-2638 ms, mean 1785 ms SD 304) and synovial fluid (T1 value range 3867-4129 ms, mean 3915 SD 899) at 3 T. CONCLUSION: T1 values measured in synovitis in patients with osteoarthritis of the knee demonstrated a range of values distinct to those measured in muscle and synovial fluid at 3 T. This offers potential for the use of T1 maps to delineate or quantify synovitis in patients who are unwilling or unable to receive injectable contrast agents.


Subject(s)
Magnetic Resonance Imaging , Osteoarthritis, Knee/diagnostic imaging , Synovitis/diagnostic imaging , Female , Humans , Image Processing, Computer-Assisted , Knee Joint/diagnostic imaging , Magnetic Resonance Imaging/methods , Male , Middle Aged , Prospective Studies
8.
Cancer Res ; 59(11): 2718-23, 1999 Jun 01.
Article in English | MEDLINE | ID: mdl-10363997

ABSTRACT

A large naive human single-chain (sc) Fv phage library was used to search for tumor-associated antigens by panning with a lung adenocarcinoma cell line, 1264, and counter-selecting with a nontumor bronchial epithelial cell line, BEAS-2B. After three rounds of subtractive panning, 239 of 673 clones analyzed bound selectively to 1264 tumor cells in a phage ELISA. Diversity analysis of these tumor-selective clones by BstNI fingerprinting and nucleotide sequencing revealed 14 distinct scFv fragments. Four clones bound selectively to 1264 over BEAS-2B cells when analyzed by a more discriminating flow cytometric assay using scFv. Moreover, these clones showed only limited cross-reactivity to several primary human cell lines. One clone, LU30, also cross-reacted strongly with the lung adenocarcinoma line, A549. The LU30 antigen was identified as decay-accelerating factor (CD55) by expression cloning from a 1264 cDNA library. The mean number of decay-accelerating factor molecules on the surface of 1264 and BEAS cells used for panning and counter-selection was estimated as 75,000 +/- 5,000 and 13,000 +/- 10,000, respectively. Thus, phage library panning combined with expression cloning permits identification of antibodies and their cognate antigens for proteins that are differentially expressed on the surface of distinct cell populations.


Subject(s)
Antigens, Tumor-Associated, Carbohydrate/analysis , CD55 Antigens/analysis , Immunoglobulin Variable Region/analysis , Cell Line , Cross Reactions , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Humans , Tumor Cells, Cultured
9.
J Mol Biol ; 270(1): 26-35, 1997 Jul 04.
Article in English | MEDLINE | ID: mdl-9231898

ABSTRACT

Structure-guided phage display was used to select for combinations of interface residues for antibody C(H)3 domains that promote the formation of stable heterodimers. A C(H)3 "knob" mutant was made by replacement of a small residue, threonine, with a larger one, tryptophan: T366W. A library of C(H)3 "hole" mutants was then created by randomizing residues 366, 368 and 407, which are in proximity to the knob on the partner C(H)3 domain. The C(H)3 knob mutant was fused to a peptide flag and the C(H)3 hole library was fused to M13 gene III. Phage displaying stable C(H)3 heterodimers were recovered by panning using an anti-flag antibody. Phage-selected C(H)3 heterodimers differed in sequence from the previously designed heterodimer T366W-Y407'A, and most clones tested were more stable to guanidine hydrochloride denaturation. The thermal stability of individual C(H)3 domains secreted from Escherichia coli was analyzed by differential scanning calorimetry. One heterodimer, T366W-T366'S:L368'A:Y407'V, had a t(m) of 69.4 degrees C, which is 4.0 deg.C higher than that for the designed heterodimer and 11.0 deg.C lower than that for the wild-type homodimer. The phage-selected C(H)3 mutant maintained the preference for forming heterodimers over homodimers as judged by near-quantitative formation of an antibody/immunoadhesin hybrid in a cotransfection assay. Phage optimization provides a complementary and more comprehensive strategy to rational design for engineering homodimers for heterodimerization.


Subject(s)
Antibodies/metabolism , Bacteriophage M13/genetics , Immunoglobulin G/chemistry , Immunoglobulin G/genetics , Immunoglobulin Heavy Chains/genetics , Amino Acid Sequence , Antibodies/chemistry , Antibodies/genetics , Base Sequence , Binding Sites , CD3 Complex/genetics , CD3 Complex/immunology , CD4 Immunoadhesins/genetics , Calorimetry, Differential Scanning , Dimerization , Gene Library , Guanidine , Guanidines/chemistry , Guanidines/pharmacology , Immunoglobulin G/metabolism , Immunoglobulin Heavy Chains/chemistry , Immunoglobulin Heavy Chains/metabolism , Molecular Sequence Data , Mutation , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Selection, Genetic , Sequence Analysis, DNA , Transfection
11.
Arch Dis Child Fetal Neonatal Ed ; 88(6): F525-30, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14602704

ABSTRACT

BACKGROUND: Previous studies have used the dynamic susceptibility contrast enhanced (DSCE) magnetic resonance (MR) imaging technique to measure cerebral perfusion in adults. OBJECTIVE: To assess the feasibility of the technique in a heterogeneous cohort of sick human infants and identify cerebral perfusion abnormalities. METHODS: Perfusion measurements were made by characterising the changing concentration of an injected bolus of contrast agent using a series of MR images acquired during the first pass of the contrast bolus. Qualitative values of relative cerebral blood flow (rCBF) were then calculated from these data on a pixel by pixel basis to generate parametric maps of perfusion. RESULTS: Images of perfusion were successfully calculated from 12 out of 27 neonates and infants, all with established cerebral pathology. Normal vascular anatomical structures such as the circle of Willis were identified within all calculated images. Values of rCBF were generally larger in grey matter than in white matter. In several patients, perfusion abnormalities resulted in structural abnormalities which were detected in conventional MR imaging at follow up. The acquisition of perfusion data was most difficult when the least mature brains were examined because of motion artefacts and a smaller head size with a lower level of rCBF than adults. CONCLUSIONS: This preliminary study shows that: (a) maps of rCBF can be acquired from neonates and infants; (b) characterisation of the bolus passage becomes progressively easier as the brain matures; (c) early abnormalities in cerebral perfusion may have negative prognostic implications; (d) the main difficulty when using the DSCE technique to study neonates relates to image artefacts resulting from bulk head motion.


Subject(s)
Cerebrovascular Circulation , Magnetic Resonance Imaging/methods , Brain/pathology , Brain/physiopathology , Brain Diseases/pathology , Brain Diseases/physiopathology , Cerebrovascular Disorders/pathology , Cerebrovascular Disorders/physiopathology , Cohort Studies , Contrast Media , Feasibility Studies , Humans , Image Enhancement/methods , Infant , Infant, Newborn , Infant, Newborn, Diseases/pathology , Infant, Newborn, Diseases/physiopathology , Infant, Premature/physiology
12.
Magn Reson Imaging ; 8(3): 261-6, 1990.
Article in English | MEDLINE | ID: mdl-2195273

ABSTRACT

An observation was made that subtracted images generated by an SR/IR interleaved pulse sequence on a low field strength magnetic resonance imager (M&D Technology Ltd, Aberdeen, Scotland) contained contrast between pathological and normal tissues that was not explained by either T1 or T2 weighting alone. A theoretical model for this image has been derived and its validity confirmed by phantom experiments. It is shown that the subtracted image is dependent on the product of T1 and T2 prolongation for contrast. This type of image might be of use in screening for unknown pathologies and such techniques may shorten routine patient imaging times.


Subject(s)
Magnetic Resonance Imaging/methods , Models, Theoretical , Subtraction Technique , Gadolinium , Magnetic Resonance Imaging/instrumentation , Mathematics , Time Factors
13.
Br J Radiol ; 68(809): 463-70, 1995 May.
Article in English | MEDLINE | ID: mdl-7788230

ABSTRACT

In a previous study using dynamic contrast-enhanced TurboFLASH (DCETF) for demonstration of the portal venous system we found that this technique showed more liver lesions than T2 weighted spin echo (T2WSE) imaging in the same patients. In this study we have formally compared axial T2WSE images (TR 2000, TE 45/90) with TurboFLASH images (TR 135, TE 4, FA 80 degrees) acquired immediately after bolus injection of Gd-DTPA (0.1 mmol kg-1) in 41 patients referred for hepatic magnetic resonance imaging (MRI) prior to surgery for liver lesions. The images of each sequence were independently reviewed by two observers. The lesions were counted and each sequence was scored for conspicuity, level of artefact and subjective image quality. Contrast-to-noise ratios using user defined regions of interest were calculated. Significantly more lesions were seen on DCETF (n = 186) images than on T2WSE (n = 123) images (p < 0.001). Lesion conspicuity was equal in 53% of cases, better on DCETF in 36% and better on T2WSE in 11%. Contrast-to-noise ratios were significantly higher on DCETF images (p < 0.05). DCETF imaging provided a substantial improvement in lesion detection compared with T2WSE imaging.


Subject(s)
Liver Neoplasms/diagnosis , Magnetic Resonance Imaging/methods , Organometallic Compounds , Pentetic Acid/analogs & derivatives , Adult , Aged , Carcinoma, Hepatocellular/diagnosis , Colorectal Neoplasms/pathology , Contrast Media , Female , Gadolinium DTPA , Hemangioma/diagnosis , Humans , Liver Neoplasms/secondary , Male , Middle Aged , Observer Variation
14.
Br J Radiol ; 60(713): 423-7, 1987 May.
Article in English | MEDLINE | ID: mdl-3580751

ABSTRACT

The study of pulsatile cerebrospinal-fluid (CSF) flow may be useful in diagnosis of certain forms of intracranial disease. Previous techniques used to study CSF flow either are invasive or do not allow accurate measurement. Magnetic resonance imaging (MRI) offers a non-invasive method of studying the CSF pathways. Our technique uses MR phase images and allows quantitative measurement of flow velocities and volume-flow rates. Four volunteers were studied at the level of the second cervical vertebra (C2). The MRI pulse sequence was gated from the R-wave of the subject's electrocardiogram and 12 scans were taken corresponding to different times in the cardiac cycle. The variation in flow velocity throughout the cycle was plotted, and maximum caudad and cephalad flow velocities and flow rates were calculated. Good agreement was found between three of the four volunteers. The mean maximum caudad velocity was 2.91 cm s-1 occurring at a mean time of 190 ms after the R-wave. This corresponds to a mean maximum flow rate of 4.13 ml s-1. The total imaging time for each study was about 1 h. Technical developments, allowing simultaneous acquisition of several images throughout the cardiac cycle, will reduce this time significantly.


Subject(s)
Cerebrospinal Fluid/physiology , Magnetic Resonance Spectroscopy , Heart Rate , Humans , Pulsatile Flow
15.
Br J Radiol ; 66(783): 214-22, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8472114

ABSTRACT

The purpose of this study was firstly to show the diagnostic value of a rapid acquisition multislice sequence (TurboFLASH) during bolus injection of gadolinium-DTPA by comparing it with the pulse sequences currently used for abdominal studies and secondly to develop improved scanning protocols for the liver. Patients were referred for upper abdominal studies including portal vein assessment. 40 patients were imaged in the coronal plane using a multislice TurboFLASH (TF) sequence (TR = 100; TE = 4) acquired during a breath-hold period of 19 s. The short echo time allows up to 11 slices of 5 mm thickness to be acquired simultaneously. Images were obtained before, during and after bolus administration of Gd-DTPA. The slices from each acquisition were combined using a maximum intensity projection algorithm to include all the vessels on a single image. Initially each patient was scanned using a conventional axial T2 weighted spin-echo sequence (T2W-SE) (TR2000; TE = 45/90) and a coronal T1 weighted spin-echo sequence (TR450; TE = 15). The clarity of the demonstration of vascular anatomy was compared and scored for all sequences by two radiologists. Vessel patency, the conspicuity of mass lesions and the spread of tumour to adjacent structures were also scored. The anatomy of the main portal vein was significantly better shown by coronal TF images after bolus injection than on T2W-SE images or TF before Gd-DTPA. The right and left portal veins were equally well shown by coronal TF with Gd-DTPA and T2W-SE images. There was no significant difference between contrast enhanced TF and T2W-SE imaging in visualization of the hepatic veins. More lesions were demonstrated by post-contrast TF than by T2W-SE imaging. Portal venous occlusion was better appreciated by post-contrast TF. Our results demonstrate that Gd-DTPA TF imaging improves visualization of the main portal vein compared with SE sequences and provides a more accurate assessment of vessel patency. The segmental anatomy of the liver is better appreciated and the demonstration of focal liver lesions compared with T2W-SE images is improved during the non-equilibrium phase of enhancement. TF acquisitions before and after Gd-DTPA are obtained in approximately 5 min; thus a marked reduction in examination time can be achieved.


Subject(s)
Liver/blood supply , Magnetic Resonance Imaging/methods , Portal Vein/pathology , Gadolinium DTPA , Hepatic Artery/pathology , Hepatic Veins/pathology , Humans , Liver Diseases/pathology , Liver Neoplasms/pathology , Organometallic Compounds , Pancreatic Neoplasms/pathology , Pentetic Acid , Vena Cava, Inferior/pathology
16.
Br J Radiol ; 66(792): 1103-10, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8293253

ABSTRACT

A prospective study using contrast enhanced turbo-FLASH (Fast Low-Angle Shot) magnetic resonance (MR) angiography was performed to assess the arterial anatomy in patients who had advanced atherosclerotic aortoiliac disease. This new imaging sequence was employed in 17 patients and the results were compared with conventional abdominal aortography. MR angiography accurately detected all aortic occlusions (3/3), their sites and their extent. All nine iliac occlusions were correctly identified (sensitivity 100%, specificity of 90%). The sensitivity was 100% for stenosis of 50% or greater in the abdominal aorta, and the iliac and common femoral arteries. The degree of stenosis was overgraded in 20 of 51 lesions (39.2%). Mild stenosis was overgraded as moderate stenosis in 10 and as severe stenosis in three. Moderate stenosis was overgraded as severe stenosis in four. None of the mild or moderate stenoses resulted in areas of signal voids suggestive of occlusions. Three severe stenoses were seen as areas of signal voids (two iliac, one femoral). In the eight patients who had in total 10 aneurysmal dilatations of the aorta or the iliac arteries, MR angiography was superior in demonstrating the true extent of the aneurysms. We conclude that turbo-FLASH MR angiography has the potential to be a useful non-invasive imaging technique for patients with advanced aortoiliac disease.


Subject(s)
Aortic Diseases/diagnosis , Arteriosclerosis/diagnosis , Iliac Artery/pathology , Magnetic Resonance Imaging/methods , Aged , Aneurysm/diagnosis , Aneurysm/pathology , Aorta, Abdominal/pathology , Aortic Aneurysm, Abdominal/diagnosis , Aortic Aneurysm, Abdominal/pathology , Aortic Diseases/pathology , Aortography/methods , Arterial Occlusive Diseases/diagnosis , Arterial Occlusive Diseases/pathology , Arteriosclerosis/pathology , Contrast Media , Female , Femoral Artery/pathology , Gadolinium DTPA , Humans , Male , Middle Aged , Organometallic Compounds , Pentetic Acid/analogs & derivatives , Prospective Studies
17.
Br J Radiol ; 74(880): 384-92, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11387160

ABSTRACT

Magnetic resonance (MR) is well suited to imaging the pericardium. High resolution images synchronized with the cardiac cycle can be obtained in any plane. The wide field of view allows additional anatomical and functional information to be obtained from adjacent structures such as the aorta, pleura, lungs and mediastinum. MR is particularly useful in cases of pericardial constriction without an associated effusion, in patients with complex or loculated pericardial effusions and in pericardial tumours. In this article we illustrate the characteristic MR features of a variety of pericardial pathologies.


Subject(s)
Cysts/diagnosis , Heart Diseases/diagnosis , Pericardium , Adult , Constriction, Pathologic , Female , Heart Neoplasms/diagnosis , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Pericarditis/diagnosis
18.
Nucl Med Commun ; 24(7): 763-9, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12813194

ABSTRACT

The calculation of ejection fraction using gated single photon emission computed tomography (SPECT) has been widely validated against a range of other techniques. There have been fewer studies validating left ventricular volumes. We compared quantitative gated SPECT (QGS) with magnetic resonance imaging (MRI) measurements of left ventricular ejection fraction and end diastolic volume in 50 patients with a large range of ventricular dimensions. MRI data were obtained using a turbo gradient echo pulse sequence (TGE) in 17 patients and a steady state free precession pulse sequence (SSFP) in 33 patients. There was good correlation between ejection fraction and end diastolic volume measurements from SPECT and MRI (r=0.82, r=0.90, respectively) but the mean SPECT values were significantly lower (ejection fraction, 6.6+/-6.4% points; end diastolic volume, 18.4+/-25.4 ml) than those obtained from MRI. Bland-Altman analysis showed some large differences in individual patients but no trends in the data either in ejection fraction over a range from 15% to 70% or in end diastolic volume, range 75-400 ml. SSFP gave a larger difference for end diastolic volume measurement compared to SPECT than did TGE, although this difference did not reach significance. Both SSFP and TGE gave similar values for the difference between MRI and SPECT for the measurement of ejection fraction. We suggest that the difference in EF may be a result of 8 frames being used for gating in QGS but 12-18 for MR. Differences in volumes may be related to the different spatial resolution and the exclusion or inclusion of trabeculation and papillary muscles between SPECT and MRI. Differences between SSFP and TGE may be caused by differing delineation of the endocardial border, dependent on the particular acquisition sequence. In conclusion, QGS values correlated well with MRI, but a correction factor may be needed if direct comparison is made.


Subject(s)
Gated Blood-Pool Imaging/methods , Magnetic Resonance Imaging, Cine/methods , Myocardial Infarction/diagnosis , Organophosphorus Compounds , Organotechnetium Compounds , Stroke Volume , Tomography, Emission-Computed, Single-Photon/methods , Female , Heart Ventricles/diagnostic imaging , Humans , Male , Middle Aged , Myocardial Infarction/diagnostic imaging , Radiopharmaceuticals , Reproducibility of Results , Sensitivity and Specificity , Statistics as Topic
19.
J Am Vet Med Assoc ; 213(12): 1755-9, 1998 Dec 15.
Article in English | MEDLINE | ID: mdl-9861970

ABSTRACT

OBJECTIVE: To determine whether cytologic examination of exfoliative specimens obtained during endoscopy was as useful as histologic examination of mucosal biopsy specimens for the diagnosis of gastrointestinal tract disease in dogs and cats and to compare the diagnostic accuracy of 2 techniques (brush or touch) in preparing specimens for cytologic examination. DESIGN: Prospective case series. ANIMALS: 85 dogs and 23 cats. PROCEDURE: Specimens for cytologic and histologic examination were obtained during routine endoscopic examination of the stomach, small intestine, and colon. A diagnosis was made on the basis of cytologic findings (graded objectively) and compared with the diagnosis on the basis of histologic findings. RESULTS: The diagnostic accuracy of cytologic examination was high for all 3 organs. Sensitivities, specificities, and predictive values of positive and negative results were > 90% in most instances. The diagnostic accuracy of the brush technique was equal or superior to that of the touch technique for 84% of specimens. The brush technique was most useful in detecting cellular infiltrates in the lamina propria, whereas the touch technique was more likely to detect acute mucosal inflammation. Percentages of false-positive (3.2%) and false-negative (6.9%) cytologic interpretations were low. CLINICAL IMPLICATIONS: Endoscopy is safe and requires little time to procure specimens for cytologic examination, which can be obtained concurrently with mucosal biopsy specimens. Cytologic examination of exfoliative specimens obtained during endoscopy is a useful and reliable adjunct to histologic examination of biopsy specimens in the diagnosis of gastrointestinal tract disease in dogs and cats.


Subject(s)
Cat Diseases/diagnosis , Dog Diseases/diagnosis , Gastric Mucosa/pathology , Gastrointestinal Diseases/veterinary , Intestinal Mucosa/pathology , Animals , Biopsy/methods , Biopsy/veterinary , Cat Diseases/pathology , Cats , Cytological Techniques/veterinary , Dog Diseases/pathology , Dogs , Endoscopy, Gastrointestinal/veterinary , Gastric Mucosa/microbiology , Gastrointestinal Diseases/diagnosis , Gastrointestinal Diseases/pathology , Intestinal Mucosa/microbiology , Sensitivity and Specificity
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