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S Reichelt

Publications and source records attributed to S Reichelt.

26 records · Page 2Linked to original sources
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

[Preliminary results with digital luminescence radiography in radiotherapy].

Port films in radiation therapy suffer from low image contrast und exposure errors. We examined the potential of computed radiography with a storage phosphor system (FCR-901/Siemens Digiscan) to overcome these drawbacks. Port films of various treatment sites were obtained for both, conventional films and digital storage phosphor screens with a DuPont cassette and steel intensifier screens under identical exposure settings. We examined port films from a linear accelerator and from a 60Co source. We found a superior contrast in the digital images and an almost total elimination of exposure errors. The differences between digital and conventional images, however, were less pronounced with films from the 60Co source. Unsharp mask filtering (medium kernel size, moderate enhancement) further improved image quality. Several sources of artefacts in the digital images could be described.

Cobalt Radioisotopes↗
PubMed1989

[Roentgen diagnosis of the foot].

Diagnostic modalities in trauma studies of the foot include conventional radiography, ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), and digital projection radiography (DR). Several projections and special views of the conventional radiographic technique are shown with special respect to the hindfoot and the subtalar joint. The importance of ultrasound for soft tissue diagnosis is emphasized. Other modalities (CT, MRI, DR) are illustrated.

Foot↗
PubMed1989

[Effects of roentgen contrast media containing barium sulfate on enterocutaneous fistulas].

Fistulation in the wake of thoracic and epigastric interventions are conservatively treated, as a rule, because of the high rate of complications expected from reoperation. With properly functioning anastomotic transit, insufficiencies usually undergo spontaneous healing, within four to six weeks. Enterocutaneous fistulae developed in 29 of 271 patients with intrathoracic oesophagogastric or oesophagojejunal anastomosis. Syringeal ramification into pleural or abdominal cavities were ruled out by means of an absorbable contrast medium, before barium sulphate was orally administered to all patients. Thoracic fistulae were closed after 21.8 days on average, while 20.3 days was the average period required for closure of epigastric fistulae. Barium sulphate was found to exercise stimulating effects on fistular tissue granulation, so that obliteration of the fistular system occurred much sooner, as compared to conservative treatment. The patient's quality of life can thus be improved, and hospitalisation can be shortened. Neither locally delimited nor systemic complications were observed in any of the cases described.

Adult↗
PubMed1987

[Atypical ultrasound picture of pleomorphic adenoma].

Presentation of an atypical sonomorphology in a case of pleomorphic adenoma of the parotid gland. The tumour was resected and worked up for histological examination. The results emphasise the difficulty of differentiating the subtypes of parotid neoplasms by ultrasonography alone.

Adenoma, Pleomorphic↗
PubMed1987

[Clinical aspects and therapy of Kaposi's sarcoma].

Three own cases are presented in order to discuss the clinical characteristics as well as the therapy of the Kaposi syndrome. This disease occurs very rarely. In its typical form it has to be classified as semi-malignant. Generally it takes an extended course over many years. In case of loco-regional tumors, radiotherapy is considered to be the method of choice. It should be performed in an extended-field technique allowing to reduce the recurrence rate and to achieve a better local tumor control. The total dose is individually determined between 25 and 40 Gy.

Adult↗