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H Rosenthal

Publications and source records attributed to H Rosenthal.

At least 55 records · Page 3Linked to original sources
PubMed1992

[Optimization of filtration and lighting parameters in pictures of the hand using digital luminescence radiography].

The appearance of digital radiographs were markedly influenced by post-processing. To optimise images of the hand, radiographs of 7 patients with arthritis were modified by various filters. 6 observers evaluated the presence or absence of erosive changes during an ROC study and the advantages of low filtration were demonstrated. Further images were prepared of anatomical preparations in which para-articular defects had been made and of a hand phantom covered in perforated plexiglass. Limited filtration and low enhancement factors again provided the best results. Dose reduction of 50% resulted in a significant deterioration in the ability to recognise erosions and artificial lesions.

Arthritis↗
PubMed1991

Reliability of testing measures in Duchenne or Becker muscular dystrophy.

In a multiinstitutional collaborative study, we ascertained the interevaluator and intraevaluator reliability of six physical therapists who performed assessment measures on 36 boys (11.7 +/- 3.9 years) with Duchenne or Becker muscular dystrophy. Upper and lower extremities were evaluated by manual muscle testing for function, range of motion, and strength. The data were analyzed using intraclass correlation coefficients (ICCs). For the interevaluator phase, ICCs were as follows: average muscle strength, .90; range of motion, .76; and upper extremity functional performance, .58. For the intraevaluator phase, corresponding ICCs were .80 to .96; .33 to .97; .34 to 1.00. Our results confirm and extend observations by others that these assessment measures are sufficiently reliable for use in a multiinstitutional collaborative effort. Such results can be used to design clinical trials that have sufficient statistical power to detect changes in the rate of disease progression. Investigators planning clinical trials in a multiinstitutional collaborative setting should first standardize the assessment methods, provide evaluator training, and document reliability.

Child↗
PubMed1991

[Complications of osteosynthesis in the x-ray picture].

Internal and external fixation devices are widely used in traumatology and orthopedic surgery. Early radiographic detection of complications due to bone surgery is based on a thorough knowledge of the different types of implants and their biomechanical properties. The development of early and late complications is demonstrated.

Equipment Failure↗
PubMed1990

[Significance of neu-protein for prognosis of breast cancers].

In 147 primary breast carcinomas, over-expression of NEU-protein was detected immuno-histochemically. 20 tumours (13.6%) showed a positive reaction. Correlations with established prognostic factors, showed a significant relationship to unfavourable histological grading and negative oestrogen receptor status, as well as to the negative status of both oestrogen and progesterone receptors. However, no correlation could be demonstrated with the progesterone receptor alone. Only a trend without significance was demonstrated to the tumour size and proliferation rate-indicated by the Ki-67 antibody. No correlation existed to the status of the axillary nodes. Overexpression of NEU-protein proved to have a significant influence on the disease-free survival and overall survival in a median follow-up time of 31 months. Nevertheless, this could be shown only for tumours with metastasis in axillary nodes, but not for nodal negative tumours. A possible Longer follow-up time is necessary, to show a difference of results for the latter group.

Biomarkers, Tumor↗
PubMed1990

[Chemical embolization of carcinoid metastases in the liver].

We performed chemo-embolisation with gel foam powder and epirubicin in 11 symptomatic patients with liver metastases from carcinoids. In all cases the symptoms regressed completely after the procedure. In two patients the liver was re-embolised because of tumour growth and both again became symptom-free. In one case, increasing extra-hepatic tumour growth was treated with interferon. One female patients died seven days after the procedure from renal failure and from complications of cerebral oedema. Two other patients died from extensive extra-hepatic tumour in the skeleton and lungs at 88 and 97 weeks after embolisation, respectively. The remaining patients are still symptom-free at 18 to 161 weeks.

Adult↗
PubMed1990

Magnetic susceptibility effects of trabecular bone on magnetic resonance imaging of bone marrow.

High-field spectroscopic studies at 5.88 tesla (T) indicate significant T2* shortening of water in suspensions of powdered bone, interpreted to be a result of magnetic susceptibility differences between bone particles and water. The authors investigated the effects of magnetic susceptibility differences between trabecular bone and water on magnetic resonance (MR) images at 0.6 T. The phantom was constructed of macerated intact trabecular human bone immersed in water. Although susceptibility-induced magnetic field inhomogeneities were detected by spectral line broadening by using an asymmetric spin-echo technique, the results show only a modest T2* shortening at this field strength. As expected, no T1 effect of trabecular bone was observed. Although susceptibility effects of trabecular bone may have a small impact on the signal intensity of MR images of bone marrow at midfield strength, the observed field strength dependence of these effects would predict significant susceptibility effects on clinical images at higher field strength.

Bone Marrow↗
PubMed1990

Storage phosphor versus screen-film radiography: effect of varying exposure parameters and unsharp mask filtering on the detectability of cortical bone defects.

Diagnostic performance with storage phosphor radiography is influenced by exposure parameters and digital filtering algorithms. The authors compared the detectability of cortical lesions in excised human femoral shafts on state-of-the-art screen-film radiographs and storage phosphor digital radiographs. For the digital system, the effect of varying exposure parameters (photon flux and tube voltage) and unsharp mask filtering (kernel size and enhancement factor) was tested. Analysis of receiver operating characteristics was performed for 10,560 observations made by eight radiologists. Under identical exposure conditions, storage phosphor imaging yielded no significant advantages over conventional screen-film radiography. Although large variations in exposure dose are possible with storage phosphors, the potential for dose reduction was limited even by means of an increase in tube voltage. The performance with unsharp masked images declined with decreasing kernel size and pronounced enhancement.

Bone and Bones↗
PubMed1990

[Cultivation technics for freshwater fish].

A general overview is presented on the various cultivation techniques in modern freshwater aquaculture. Included are overall production figures for finfish production in the most important producing countries of Europe. Major emphasis is placed on the situation of aquaculture development in the Federal Republic of Germany, providing details on the structure of the industry in the states of Bavaria, Lower Saxony, and Schleswig-Holstein. The trend towards intensification and its implications to system performance is described. The development of recirculation systems, particular for eel farming, is outlined, indicating the various problems related to system design, local conditions and species requirements. Future trends and research needs are identified.

Animal Husbandry↗
PubMed1989

[The immunohistochemical growth fraction (Ki-67) of breast cancers: relations to tumor spread, tumor morphology and receptor testing].

245 breast cancer tissues were analysed immunohistochemically, using monoclonal antibody Ki-67, which spezifically reacts with a nuclear antigen of proliferating cells and represents the so-called growth fraction. According to the number of positive cells, three Ki-score categories (I-III) were established. The results were compared with prognostic variables (Histological grading, DNA-cytophotometry), staging parameters, immunocytochemical (ER-ICA, mPRI), and biochemical (DCC) hormone receptor assay. We found a good correlation between Ki-67 and grading (Bloom and Richardson): G 1-tumors had small growth fractions, in contrast to G-III carcinoma, which showed a high percentage of Ki-Score III. Receptor negative cases had a large growth fraction and receptorpositive ones showed an uniform distribution. The comparison between Ki-67 and tumor spread or DNA-Cytophotometry showed no correlation. The majority of 31 recurrent tumors not only had a large number of positive cells, but also a definite dependence was found between Ki-Score and length of the disease-free period. Ki-67 seems to be an important immunohistochemical marker of breast cancer, which contributes to the individual assessment of the disease and can possibly give predictions on tumor development and response to radiation and systemic therapy.

Adult↗
PubMed1989

[Chemoembolization of hepatocellular carcinoma--computed tomographic follow-up observation].

The prognosis of unresectable hepatocellular carcinomas is bad. Untreated, survival is 1.6 to 2.5 months. Systemic chemotherapy has little effect and is associated with marked side effects. Tumour cells are supplied almost exclusively by the hepatic artery, whereas normal liver tissue is supplied by the hepatic artery and portal vein. Consequently, interruption of arterial blood flow results in damage to the carcinoma without affecting the rest of the liver. Lipiodol is an oily contrast medium which is taken up selectively by the tumour and can be demonstrated in tumour, in the interstitium and in blood vessels. We used lipiodol emulsified with cisplatin and epirubicin successfully in 22 patients with inoperable liver cell carcinomas. The treatment was well tolerated, apart from some nausea and mild upper abdominal discomfort. Survival time from first diagnosis and the first embolisation was ten months longer than expected survival or that following systemic chemotherapy.

Aged↗
PubMed1989

"Single-exposure" dual energy digital radiography in the detection of pulmonary nodules and calcifications.

We studied the detectability of mineralized and non-mineralized simulated pulmonary nodules with dual energy digital radiography. "Soft tissue" and "bone" images (pixel size = 0.2 mm, 10 bits deep) were obtained with subtraction image processing after a single simultaneous exposure (100 kVp, 8 mAs, 17 mR skin exposure dose) of two storage phosphors with an interleaved 0.9 mm copper wafer. Three classes of paraffin-based nodules (0.5 to 3.0 cm) of varying mineral concentration (0, 120 and 190 mg/cm3 K2HPO4) were randomly positioned on the chest wall of two healthy volunteers to simulate calcified and non-calcified nodules. The average receiver operating characteristics (ROC) area of six readers (n = 2880 observations) showed that digital "bone" images (ROC area: 0.77 +/- 0.03) were significantly better (P less than 0.04) than conventional radiographs (OC Film, Lanex medium screens, 141 kVp, 19 mR skin exposure dose) (ROC area: 0.71 +/- 0.05) in detecting calcification in nodules. The unsubtracted digital images of lower kilovoltage were not superior to the 141 kVp conventional radiographs in a subgroup of two readers (ROC area: 0.73 +/- 0.02). Digital "soft tissue" images were equivalent to conventional chest radiographs in detecting soft tissue pulmonary nodules (ROC areas: 0.92 +/- 0.04 and 0.92 +/- 0.05, respectively.

Adult↗
PubMed1989

Body fat distribution measured with CT: correlations in healthy subjects, patients with anorexia nervosa, and patients with Cushing syndrome.

Computed tomography (CT) was used to study fat distribution in three groups of women of comparable age: 39 healthy volunteers, 15 patients with anorexia nervosa, and seven with Cushing syndrome. Patients with anorexia nervosa had a fivefold decrease in subcutaneous fat and only a twofold decrease in intraabdominal fat compared with the values for the volunteers. Patients with Cushing syndrome had less than a twofold increase in subcutaneous fat and greater than a fivefold increase in intraabdominal fat compared with values for the healthy subjects. These findings suggest that fat in different body compartments responds differently to disease processes and that CT can be used to measure these changes.

Adipose Tissue↗
PubMed1989

Improved control of image optical density with low-dose digital and conventional radiography in bedside imaging.

The technical and diagnostic performance of simultaneously acquired low-dose (44% of standard dose) storage-phosphor digital radiographs (system resolution = 0.2 mm, 10 bits) were compared with those of standard-dose conventional bedside radiographs of the chest in 32 patients. The mean optical density (OD) of the lungs (800 measurements) was closer to the ideal density with digital radiography (1.45 OD +/- 0.20 [standard deviation] vs 1.75 OD +/- 0.53) and was less often outside the usable range (2.5% vs 42.5%). Receiver operating characteristic analysis for detection of simulated nodules and monitoring devices (nine readers, 4,608 observations) showed that digital radiography was superior to conventional radiography (P less than .05) for four of the nine readers and equivalent to conventional radiography for five readers. The authors concluded that digital radiography produces more consistent and ideal image density and performs at least as well as conventional radiography under phantom test conditions.

Absorptiometry, Photon↗
PubMed1989

Desmoplastic fibroma arising in fibrous dysplasia. Chromosomal analysis and review of the literature.

A desmoplastic fibroma of bone arose in the fibula of a 17-year-old boy with fibrous dysplasia. This may be the second case of this rare histopathologic association reported in the literature. Benign bone tumors have not previously been subjected to cytogenetic analysis. Analysis of this case revealed a primary abnormal clone trisomic for both chromosomes 3 and 5 and two subclones, one trisomic for chromosome 3 and one trisomic for chromosome 5. This case may also present the first description of nonrandom karyotypic abnormalities in a benign neoplasm of bone.

Adolescent↗
PubMed1988

[Projections in conventional shoulder joint diagnosis].

Numerous projections are described in the literature for plain film radiography of the shoulder joint. A review is given of the indications, advantages and disadvantages of the most common views. The significance of special, additional views is discussed.

Humans↗
PubMed1988

[Sonography of the shoulder joint. Study technic, sonomorphology and diagnostic significance].

In the evaluation of the impingement syndrome, conventional radiography can only show secondary bony changes. Sonography is able to demonstrate the anatomy of the musculotendinous structure of the rotator cuff. Lesions can be detected with the same accuracy and specificity as by contrast arthrography. As sonography is a non-invasive method, it should be used routinely to test rotator cuff integrity. Joint effusions and proliferative synovial changes are easily demonstrated by sonography. It is thus possible to perform follow-up studies in a pre-erosive stage of rheumatoid arthritis.

Humans↗