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171.
Gülin Vural Mustafa Ünlü Tamer Atasever Izlem Özur Ayşegül Özdemir Nahide Gökçora 《European journal of nuclear medicine and molecular imaging》1997,24(3):312-315
Indium-111 octreotide and thallium-201 scintigraphic studies were compared in 21 patients (16 with palpable and five with non-palpable lesions) suspected of having breast malignancies on the basis of mammography. Early (15 min) and late (3 h)201Tl (111 MBq) and 4-h and 24-h111In-octreotide (111–148 MBq) static planar anterior images (matrix 256×256) were obtained on separate days. Images were evaluated both visually and quantitatively. Biopsy was performed following the imaging studies. Histopathology revealed 17 breast carcinomas (15 cases of invasive ductal carcinoma, one mucinous adenocarcinoma and one intraductal carcinoma) and four benign breast lesions (two fibroadenomas, one abscess and one case of fat necrosis). The means histopathologcial tumour size (mean largest diameter) was 3.38±1.9 cm.111In-octreotide detected 16 of the 17 breast cancers (94%) while201Tl detected 13 of them (76%). Both111In-octreotide and201Tl missed one nonpalpable carcinoma showing only an isolated cluster of microcalcifications on mammography. The smallest tumour size detected by both agents 1.5×1.5 cm. Of the four benign lesions, only the breast abscess revealed both201Tl and111In-octreotide uptake.111In-octreotide scan also showed tracer uptake in five of the six patients with histologically proven axillary metastases, while four of these six patients showed201Tl uptake. The tumour/background (T/B) ratios of late111In-octreotide and201Tl images were 1.71±0.38 and 1.46±0.30 respectively (P=0.039). In this preliminary study,111In-octreotide yielded more favourable results than201Tl in the detection of breast carcinomas. However, the diagnostic efficacy of111In-octreotide imaging needs to be investigated in larger patient series. 相似文献
172.
173.
Early detection of avascular necrosis of the femoral head following renal transplantation 总被引:3,自引:0,他引:3
B. Fink S. Degenhardt C. Paselk T. Schneider U. Mödder W. Rüther 《Archives of orthopaedic and trauma surgery》1997,116(3):151-156
This prospective study included 43 patients undergoing renal transplantations. Magnetic resonance imaging (MRI) and X-rays of the hip joints were produced 3 and 12 months after transplantation. In 6 hip joints of 4 patients (9.3%), we discovered femoral head necroses just 3 months after transplantation. Three of the hip joints affected were symptomatic and 3 painless. The MR images taken 12 months after transplantation revealed no additional femoral head necrosis. A core decompression was performed on 3 joints. In contrast to those with core decompression, the femoral heads without core decompression showed a progression of the necrosis in 2 of 3 cases. All 4 patients with femoral head necroses were younger than 50 years and exhibited a premature conversion of the haematopoietic marrow to fatty marrow in the area of the proximal femoral metaphysis. A similar premature conversion to fatty marrow was seen in 6 of the 22 (27.2%) patients younger than 50 years and without femoral head necroses. The doses in long-term steroid medication and the steroid doses during the rejection periods of the patients with femoral head necroses were not significantly higher than those for the patients with premature conversion to fatty marrow. The latter had also not received significantly higher doses than the patients whose MRI findings were inconspicuous. 相似文献
174.
175.
Orbital hydatid cyst is rare. We present a case with CT and MRI, emphasizing the superiority of the latter.
Received: 19 August 1996 Accepted: 9 September 1996 相似文献
176.
Summary
Forty-one patients demonstrating clinical symptoms for cerebral infarction were investigated by magnetic resonance imaging
with diffusion-weighted echo-planar imaging (DWI) and T2-weighted imaging (T2WI). In 8 patients only DWI showed the cerebral
lesions clearly. One patient with positive DWI and T2WI suffered from HSV encephalitis. DWI is superior to T2WI in assessment
of small cortical infarcts and cerebral infarction in patients with preexisting vascular lesions. DWI is not specific, so
other causes like cerebral hematoma and encephalitis have to be considered.
相似文献
177.
Summary Right brain-damaged patients with left spatial neglect were examined on a tactile maze task. They started to explore the right side of the maze and their search times were longer on the left side. Their performance was the same whether blindfolded or not, which contrasts with the results of other studies and probably reflects differences in task demand. The present results do not support a previous observation that visual neglect can be compensated through the tactile modality. Our patients had markedly longer search times than normal controls in the right as well as the left hemifield, and search times in both hemifields were positively correlated. The outcome of the maze test in this context may therefore depend to a large extent on impaired topo graphical processing. 相似文献
178.
L. Hernefalk P. Granström K. Messner 《Archives of orthopaedic and trauma surgery》1997,116(4):198-203
The objective of the study was to assess scintigraphic patterns and femoral shortening after femoral neck fracture in order to select predictive parameters for late complications. Eighty-eight patients with osteosynthesized femoral neck fractures were followed for 2 years with regular scintigraphic evaluations and orthoradiographic measurements of femoral length shortening. Four different patient categories were identified with regard to the late outcome: two different groups with uneventful healing and two different groups with late complications. Accordingly, a high scintigraphic uptake at 1 month may eiher point to an uneventful healing if combined with minor femoral shortening or indicate failure if combined with a high degree of femoral shortening. In contrast, low scintigraphic uptake may either reflect primary fracture healing if accompanied by minor femoral shortening or predict failure if a high degree of femoral shortening is present. Compared with using scintigraphy alone, combined scintigraphic evaluation and assessment of femoral shortening increased the accuracy for prediction of late failures from 80% to 93%. Early scintigraphic patterns after osteosynthesis of femoral neck fractures have to be validated with care. Radiographic assessment of femoral shortening, which is less invasive, gives better prognostic accuracy and should therefore be preferred for this purpose. 相似文献
179.
180.
E. Wallenböck G. Koch 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1997,382(5):257-265
The intramedullary tibial nail with a proximal angle according to Herzog was developed in order to facilitate implantation. However, the modified technique of unreamed nailing also required a shift of the point of insertion; as a consequence the proximal angle required a considerable increase in the force necessary to introduce the nail. In a study using four cadaver bones and five commercially available unreamed femoral and tibial nails, the authors demonstrate this considerable increase in insertion force and the development of pressure in the medullary cavity. The measurements made with our experimental setup clearly show that the proximal angle of the unreamed tibial nails available for our series does not have a favourable influence on insertion behaviour. As it appears, it results in an increase in the force required for insertion of the nail, thus also causing a greater strain on the bone and an increase in pressure in the medullary cavity. In contrast, the continuous bend of the nail results in a much smoother course of pressure development in the medullary cavity, which does not reach the same high values as with the unreamed tibial nails, despite the fact that less time is required for insertion of the nail. In our opinion, modification of the axial shape of the nail would result both in better implantability and easier removal. We therefore advocate such a modification of the axial shape of intramedullary tibia nails. 相似文献