摘要:

These preliminary studies of dynamic natural abundance 19F-magnetic resonance spectroscopy (19F-MRS) on 5-FU based medicines were performed in the human liver using commercial 1.5 T MRI equipment. A single tuned, custom-made circular shape surface coil with a diameter of 15 cm operating at 60 MHz was used for the 19F-MRS study. Localized proton shimming with a whole body coil was performed with adequate volume to include the observing area of the surface coil, and the line width of the water signal was less than 40 Hz. Very different spectroscopic appearance patterns of 5-FU were observed. We examined whether the pharmacokinetics in the liver of orally administered 1-hexylcarbamoyl-5-fluorouracil (HCFU) differ from those of orally administered 5'-deoxy-5-fluorouridine (5'-DFUR). This preliminary study suggested the 19F-MRS technique could be a useful method of evaluating in vivo the metabolism of 5-FU based medicines.

DOI:10.1259/bjr.72.858.10560341

出版商:The British Institute of Radiology    

年代:1999

数据来源: WILEY

摘要:

This feasibility study was performed to evaluate the suitability of MRI in defining appropriate pelvic radiotherapy treatment volumes, and to compare MRI sequences with CT for prostate cancer radiotherapy. Five patients with localized prostate cancer, imaged with four MRI sequences (spin echo (SE) T1, turbo SE (TSE) T2, high resolution TSE (HR) T2, and FLASH 3D (F3D)), compared with their corresponding CT planning scans. Segmentation ability of the following pelvic structures: prostatic apex (PA), prostate, rectum, bladder and seminal vesicles (SV), were evaluated by three independent observers. They used a five point grading scale based on the anatomical definition of the organ boundary, tissue contrast and multiplanar display. Results were averaged for the group and for each sequence. There was no significant interobserver variation in the assessed scores (p>0.1). The average scores (+/- 1 SD) for all pelvic structures assessed by each imaging sequence were CT 1.3 +/- 0.6; SE T1 2.4 +/- 0.9; TSE T2 2.4 +/- 0.7; HR T2 2.2 +/- 0.7 and F3D 3.4 +/- 0.6. Compared with CT, the average MR score for each assessed pelvic structure was higher with a trend for all transaxial MR sequences to provide improved segmentation of the PA and rectum. The F3D sequence scored highest as it provided multiplanar views and avoided the problem of partial volume averaging. MRI, compared with CT, appears to provide improved definition of pelvic treatment volumes but further work is required to confirm this and to address the issues of MRI associated distortion and dosimetry before MRI can be used routinely for pelvic radiotherapy planning.

DOI:10.1259/bjr.72.858.10560342

出版商:The British Institute of Radiology    

年代:1999

数据来源: WILEY

摘要:

Against a background of constant or decreasing budgets, this study was undertaken to investigate the economic effects of changes in selected operational parameters within a radiation treatment programme. Using financial data from the Northeastern Ontario Regional Cancer Centre and a recognized staffing model, a commercial spreadsheet has been used to calculate the cost of an 18 fraction course of radiotherapy, including all the major preparatory processes such as simulation and treatment planning. Using the spreadsheet, and on the basis of explicit and reasonable assumptions, the cost of radiotherapy has been calculated as the facility size (i.e. equipment complement) and hours of operation are varied. Based on the assumptions used, the cost of radiotherapy in a facility treating less than about 1600 patients per year starts to rise. At 400 patients per year, a course costs approximately 50% more than at 1600 patients per annum. Extended hours of operation do not appear to generate significant, if any, savings when realistic assumptions about machine lifetime and overtime payments are made. Using a spreadsheet to simulate changes in a radiation treatment programme can be an important decision-making tool, as the effects of changes in operating parameters can be demonstrated.

DOI:10.1259/bjr.72.858.10560343

出版商:The British Institute of Radiology    

年代:1999

数据来源: WILEY

摘要:

Neurofibromatosis Type 1 (NF1) is not classically associated with gastrointestinal manifestations although these patients are at increased risk of several GI complications. We describe the ultrasound, CT and barium findings in a patient with NF1 who had a huge benign plexiform neurofibroma of the ileum that was infiltrated with metastatic adenocarcinoma.

DOI:10.1259/bjr.72.858.10560344

出版商:The British Institute of Radiology    

年代:1999

数据来源: WILEY

摘要:

Mesenteric ischaemia is a rare but serious cause of abdominal pain. We present the case of a man with Sneddon's syndrome, who had symptomatic mesenteric ischaemia secondary to a superior mesenteric artery stenosis in conjunction with a hepatic artery stenosis. As far as the authors are aware, this has not previously been described in Sneddon's syndrome, which is a vascular systemic disease characterized by an association between cerebrovascular accidents and a livedo reticularis skin rash. He was treated with balloon angioplasty and stent insertion, with good symptomatic improvement. This has implications for other stenoses in this condition should they become symptomatic.

DOI:10.1259/bjr.72.858.10560345

出版商:The British Institute of Radiology    

年代:1999

数据来源: WILEY

摘要:

Perianal Paget's disease is rare. Unlike Paget's disease of the nipple, which is always associated with a subjacent breast adenocarcinoma, perianal Paget's disease is not always associated with a subjacent or visceral malignancy. The treatment recommendation in nearly all reported cases has been surgical excision. Radiation therapy is seldom used as a curative treatment. A case of perianal Paget's disease is described in whom radiation therapy was used with a curative intent after four unsuccessful surgical resections.

DOI:10.1259/bjr.72.858.10560346

出版商:The British Institute of Radiology    

年代:1999

数据来源: WILEY

摘要:

MRI is a valuable method for evaluating thoracic vascular lesions by virtue of its non-invasiveness and multiplanar capability. In addition, ionizing radiation and iodinated contrast medium are not required. Electrocardiographically gated T1 weighted spin echo MRI remains the principal technique for demonstrating the anatomy and morphology of thoracic vascular diseases. Cine MRI allows dynamic evaluation of vascular flow, whereas MR angiography is particularly useful in the two-dimensional (2D) or three-dimensional (3D) display of vascular anatomy. This pictorial review illustrates the use of 2D time-of-flight MR angiography in the assessment of various thoracic vascular conditions including aortic arch and great vessel anomalies, heterotaxic syndromes, aortic dissection, aortic or arch vessel aneurysms, pulmonary embolism, pulmonary sequestration, axillofemoral bypass and tumour/vessel relationships.

DOI:10.1259/bjr.72.858.10560347

出版商:The British Institute of Radiology    

年代:1999

数据来源: WILEY

DOI:10.1259/bjr.72.858.10560348

出版商:The British Institute of Radiology    

年代:1999

数据来源: WILEY

DOI:10.1259/bjr.72.858.10560349

出版商:The British Institute of Radiology    

年代:1999

数据来源: WILEY