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J Peiss

Publications and source records attributed to J Peiss.

12 recordsLinked to original sources
PubMed1996

Classification of lung tumors on chest radiographs by fractal texture analysis.

RATIONALE AND OBJECTIVES: The authors determine the usefulness of fractal texture analysis in classification of lung tumors on chest radiographs. METHODS: A method of fractal texture analysis was applied for classification of lung tumors on digitized chest radiographs. It was performed in 15 cases of benign lesions and in 26 cases of malignant tumors. All lesions were proved by histology. For classification, the fractal distances of the tumors were calculated and an energy measure related to the variances as a second characteristic was applied. The results were compared with those of a conventional classification method based on the co-occurrence matrix. RESULTS: Although the conventional method failed in classification of lung tumors, a clear separation between benign and malignant lesions was attained by fractal analysis. A differentiation between primary lung cancer and metastases was not possible. CONCLUSIONS: The results of our study demonstrate the usefulness of fractal texture analysis for classification of lung tumors on chest radiographs.

Fractals↗
PubMed1995

Gadopentetate-dimeglumine-enhanced MR imaging of osteonecrosis and osteochondritis dissecans of the elbow: initial experience.

Magnetic resonance imaging (MRI) was performed on seven patients with aseptic osteonecrosis (n = 4) and osteochondritis dissecans (OCD; n = 3) of the elbow. Precontrast MRI was superior to plain radiographs, which did not show any abnormality in three cases of osteonecrosis. On gadopentetate-dimeglumine-enhanced T1-weighted images, which were obtained in three patients with osteonecrosis and three patients with OCD, all cases of osteonecrosis demonstrated homogeneous enhancement of the lesions. All cases of OCD were diagnosed on plain radiographs. On MRI one showed significant enhancement of the loose body. In another case an incompletely enhancing loose body was surrounded by a diffusely enhancing region. In the third patient only a small marginal enhancement of the defect was observed. Our results suggest that MRI can improve the accuracy in diagnosis of aseptic osteonecrosis of the elbow. The use of gadopentetate dimeglumine allows the viability of the lesions or the loose bodies to be demonstrated and reparative tissue to be detected.

Adolescent↗
PubMed1994

[The magnetic resonance tomography of osteochondrosis dissecans of the knee joint after intravenous gadolinium-DTPA administration].

20 patients with osteochondritis dissecans were studied by MRI over a period of 3-34 months in order to observe healing and determine the viability of the loose fragment. After intravenous contrast, there was increased signal intensity at the junction between the fragment and the epiphyseal bed on T2-weighted sequences; this was interpreted as fibrous granulation tissue surrounding the fragment. The fragments themselves also showed increased signal intensity after gadolinium-DTPA. Intravenous gadolinium allows accurate evaluation of the junctional zone between the fragment and the epiphyseal bed by demonstrating fibrous, vascularised granulation tissue. This can be distinguished from synovial fluid, and it also demonstrates viability of the fragment.

Adolescent↗
PubMed1993

[The MR morphology of hemangiomas and lymphangiomas of the peripheral soft issues--a correlation with angiography and histology].

A retrospective analysis of the morphology and signal behaviour of T1, proton and T2-weighted spin-echo sequences has been carried out on 21 haemangiomas and 2 lymphangiomas of the peripheral soft tissues which had been examined by MRT. In 11 cases the diagnosis was confirmed histologically and in 12 by angiography. The majority of haemangiomas (19 cases) and both lymphangiomas showed hyperintense signals on T2-weighted spin-echo sequences; 2 lesions did not conform to this behaviour. MRT was a sensitive method for demonstrating vessels with high flow velocities so that it was possible to distinguish high flow haemangiomas by MRT. Apart from one thrombosed haemangioma, all 9 haemangiomas examined with iv Gd-DTPA showed homogeneous contrast uptake except for vessels with high flow velocities. One lymphangioma examined with iv Gd-DTPA was characterised by non-homogeneous contrast uptake.

Angiography, Digital Subtraction↗
PubMed1992

[The signal behavior of parathyroid adenomas in MRT--the contrast ratio of the thyroid and fatty tissue].

A quantitative analysis of signal relationships using T1, proton and T2 weighted spin echo sequences was carried out using 20 parathyroid adenomas demonstrated by MRI. T1 weighted sequences from 15 adenomas were also examined following intravenous injection of Gd-DTPA. No typical signal relationship could be defined. In 4 cases the administration of contrast medium markedly increased the contrast between the adenoma and the thyroid gland. In 12 cases the tumour could be examined histologically following removal. In 2 cases there was oedema of the tumour and corresponding increased intensity of the T2 weighted sequences; in none of the other cases was there any clear correlation between the signals and the histology.

Adenoma↗
PubMed1983

[Vinblastine, 5-fluorouracil and prednisone (VFP) as "second-line" chemotherapy. Contribution to the problem of optimal therapy sequence in metastasizing breast carcinoma].

Chemotherapy results in metastatic breast cancer reached a plateau: Remission rate and duration are nearly equivalent for several regimens but not equitoxic. We analyzed the effect of vinblastine (6 mg/m2 once a week i.v.), 5-fluorouracil (600 mg/m2 once a week i.v.) and prednisone (10-20 mg daily p.o.) as second line treatment in BC resistant to one of the other established regimens with regard to prognostic factors and pretreatment. Our results show that it is possible to produce more than one or even two remissions by consecutively applicated combinations of cytostatics with increasing aggressivity.

Adult↗