摘要:

AbstractWriting a critique and guide for authors of clinical spectroscopy research papers is a likely way of ensuring that one never sees another of one's own papers published in this field. Nevertheless, it is disappointing, though perhaps predictable, that despite its historical foundations in quantitative spectroscopy, the field has its fair share of findings that are not so obviously reconciled. Here is the view of one author, one referee, and one spectroscopy protagonist about what might be expected of a clinical spectroscopy paper. In addition to novelty, the fundamental criteria for acceptance should be that the conclusions are supported by properly and objectively quantified results, and that sufficient experimental detail is provided so that one skilled in the art could reproduce the study and its findings.

ISSN:1053-1807    

DOI:10.1002/jmri.1880020102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractTwelve patients with a high suspicion of brain metastases by previous clinical or radiologic examinations were studied in a phase III investigation with magnetic resonance (MR) imaging at 1.5 T after a bolus intravenous injection of 0.1 mmol/kg gadoteridol followed at 30 minutes by a second bolus injection of 0.2 mmol/kg gadoteridol. All lesions were best demonstrated (showed greatest enhancement) at the 0.3‐mmol/kg (cumulative) dose, with image analysis confirming signal intensity enhancement in the majority of cases after the second gadoteridol injection. More lesions were detected with the 0.3‐mmol/kg dose than with the 0.1‐mmol/kg dose, and more lesions were detected with the 0.1‐mmol/kg dose than on precontrast images. In this limited clinical trial, high‐dose gadoteridol injection (0.3‐mmol/kg cumulative dose) provided improved lesion detection on MR images specifically in intracranial metasta

ISSN:1053-1807    

DOI:10.1002/jmri.1880020103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractGadodiamide injection is a nonionic, low‐osmo‐lar formulation of a paramagnetic metal chelate complex consisting of gadodiamide and caldia‐mide sodium. The efficacy of gadodiamide injection as a magnetic resonance (MR) imaging enhancement medium was evaluated by imaging intracranial 9L‐glioma lesions induced in rats and naturally occurring lesions in dogs. T1‐ and T2‐weighted spin‐echo images were obtained before and after administration of gadodiamide injection at doses of 0.1 and 0.2 mmol/kg. On the precontrast T1‐weighted images, the intracranial lesions were not well seen, appearing isoin‐tense to normal brain parenchyma. Although the presence of disease was shown unequivocally on the T2‐weighted images, the margins of the masses could not be delineated. Postcontrast T1‐weighted images were characterized by marked enhancement of the tumor, with no change in signal intensity in the surrounding edematous brain tissue. Gadodiamide injection was efficacious in identifying areas of blood‐brain barrier breakdown associated w

ISSN:1053-1807    

DOI:10.1002/jmri.1880020104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractTo determine the safety and imaging characteristics of OMR — an effervescent solution of ferric ammonium citrate — as a bowel contrast agent, magnetic resonance (MR) imaging at 1.5 T was performed in 29 volunteers. T1‐ and T2‐weighted images of the upper abdomen and pelvis were obtained before and after oral administration of OMR at doses of 100–400 mg of iron in 300–600 mL of water. Respiratory‐ordered phase encoding and presaturation pulses were used routinely for artifact suppression. All dose levels of OMR provided marking of the bowel by increasing intraluminal signal intensity; however, the degree and percentage of small bowel opacification appeared more prominent at higher dose levels of iron. Semisolid or watery bowel movements were noted in 31% of subjects, but no clinically important laboratory abnormalities were seen. OMR improved delineation of the head of the pancreas on T1‐weighted images in 72% of subjects but was less useful in defining the body and tail. OMR is a safe and effective bowel contrast agent for MR imaging. Because artifacts due to movement of hyperintense bowel may degrade the images, OMR may be most useful on short TR/TE or fast imaging pulse sequences or when combined with antiper

ISSN:1053-1807    

DOI:10.1002/jmri.1880020105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractRadical prostatectomy specimens from 53 men with clinical stage A or B prostate cancer were retrospectively reviewed and compared with correlative axial T2‐weighted magnetic resonance (MR) images obtained just before surgery. Non‐cancerous lesions were evaluated for signal intensity and location. Focal high‐signal‐intensity areas (n = 72) were present in 81% of patients. The 26% of lesions seen in the central gland all correlated with cystic atrophy. Of the 53 lesions seen in the peripheral prostate, 47 (89%) were cystic atrophy without associated cancer, four (7.5%) cystic atrophy with cancer, and two (3.8%) focal inflammation. Focal low‐signal‐intensity areas (n = 42) were present in 60% of patients. Of the 31% of lesions in the central prostate, one‐fifth correlated with benign prostatic hyperplasia (BPH) and four‐fifths with fibrous tissue. Of the 69% of peripheral lesions, 83% corresponded to fibrous tissue, 10% to BPH, and 7% to normal tissue. Mixed lesions (n = 42) were present in 64% of patients; 86% of these were located centrally and 14% peripherally. All mixed central lesions were BPH; the peripheral lesions were areas of combined cystic atrophy and fibrosis. BPH of low or mixed signal intensity can extend into the peripheral prostate and mimic cancer. High‐intensity cystic atrophy associated with cancer can mi

ISSN:1053-1807    

DOI:10.1002/jmri.1880020106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

ISSN:1053-1807    

DOI:10.1002/jmri.1880020107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractHistologic correlation of the different magnetic resonance (MR) appearances of articular cartilage has not been studied extensively. Therefore, the authors correlated thin (high‐resolution) MR sections of articular cartilage with histologic sections. Human cadaver lumbar facet joints were imaged with a 1‐mm section thickness and a 4‐cm field of view, then sectioned and stained for histologic comparison. MR imaging patterns were identified that correlated with normal cartilage and three histologically different patterns of degener

ISSN:1053-1807    

DOI:10.1002/jmri.1880020108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractA three‐dimensional projection reconstruction technique is described for imaging boron‐11 distributions, with potential application to boron neutron capture therapy. The method samples a spherical volume of k space uniformly to obtain a 32 × 32 × 32 matrix with voxel size of 0.42 cm3. A signal‐to‐noise ratio (S/N) of 3 was obtained in 8.5 minutes in a phantom containing 75 ug/mL of boron in borocaptate sodium (BSH). Images were obtained in a dog after cessation of an intravenous infusion of BSH and again 30 minutes later, with a maximum boron S/N of about 12. Boron levels in the brain dropped about 6%‐8% and were more diffusely distributed on the images obtained 30 minutes after B

ISSN:1053-1807    

DOI:10.1002/jmri.1880020109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractPerfluorocarbons such as perfluoroctylbromide (PFOB) can be used as contrast agents in the vascular system for fluorine‐19 magnetic resonance imaging or as synthetic oxygen carriers. F‐19 imaging has been proposed for studying the vascular system, capillary flow, tissue perfusion, and tumor oxygenation. A major difficulty is that F‐19 compounds often have complex multipeak spectra. These peaks result in chemical shift artifacts, lower signal‐to‐noise ratios, and blurred images. Each peak also excites a different section when a section‐select gradient is applied. Direct inverse filtering is the simplest deconvo‐lution method for correcting such artifacts; however, two major difficulties present themselves: functional singularity and noise amplification at high frequencies. The use of a new reblurred de‐convolution (RED) method appears to overcome these problems. Although this method is based on iterative deconvolution in the spatial domain, the computational overhead is negligible. Since the point spread function and object data are already available in the time domain as FID data, RED appears to be useful for eliminating chemical shift artifacts and suppressing noise amplification while restoring the original image without los

ISSN:1053-1807    

DOI:10.1002/jmri.1880020110

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

ISSN:1053-1807    

DOI:10.1002/jmri.1880020111

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY