J. Oestmann - Academia.edu (original) (raw)
Papers by J. Oestmann
RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren, 2002
Ziel: Das Ziel der vorliegenden Studie war die alters-und geschlechtsspezifische Analyse der mech... more Ziel: Das Ziel der vorliegenden Studie war die alters-und geschlechtsspezifische Analyse der mechanischen Eigenschaften und der Knochenmineraldichte (BMD) des proximalen Humerus in verschiedenen Höhen und Regionen. Methoden: Folgende Verfahren wurden angewandt: Mechanische Indentation Testung, DXA, QCT, pQCT und die Radiogrammmetrie (Cortical Index, CI). Die Untersuchungen wurden an 70 frischen Humeri von 46 humanen Präparaten (23 weiblich, 23 männlich; Alter median: 70,5 Jahre) durchgeführt. Ergebnisse: In der Gruppe der weiblichen Humeri fand sich eine hohe Korrelation zwischen Alter und Knochenmineraldichte (r =-0,62 to-0,70 p < 0,01) mit statistisch signifikanten Unterschieden zwischen Präparaten jünger als 69 Jahre und älter als 70 Jahre (p < 0.05). In der Gruppe der weiblichen Präparate mit einem Alter über 70 Jahre waren die Knochenmineraldichtewerte im Vergleich mit den männlichen Präparaten signifikant niedriger (p < 0.05). Unabhängig vom Alter der Präparate wurde die höchste Knochenmineraldichte und Knochenfestigkeit im proximalen Abschnitt und in den medialen und dorsalen Regionen des proximalen Humerus nachgewiesen. Schlussfolgerung: Die Ergebnisse geben Aufschluss über die Frakturentstehung und stellen die Grundlage für die Entwicklung von strukturorientierten Implantaten mit einer verbesserten Implantatfixation im osteoporotischen Knochen dar.
Journal of Experimental & Clinical Medicine, 1990
RadioGraphics, 1994
The combination of computed radiography (CR) and advanced multiple beam equalization radiography ... more The combination of computed radiography (CR) and advanced multiple beam equalization radiography (AMBER) was evaluated for both single- and dual-energy chest radiography. The improved signal-to-noise ratio found with CR and AMBER resulted in a better visualization of structures in the mediastinum and basal lung than that found with CR alone. For the central lung, no improvement was seen. Because of the compressed dynamic range with CR and AMBER, contrast on hard copies and video monitors could be high without a sacrifice in image latitude. Dual-energy images showed a considerably lower noise level. The combined use of AMBER and CR promises to overcome the dynamic range limitations of digital displays while improving signal-to-noise ratio.
AJR. American journal of roentgenology, 2015
OBJECTIVE. Bronchoscopic lung volume reduction promises to become an effective treatment option i... more OBJECTIVE. Bronchoscopic lung volume reduction promises to become an effective treatment option in severe chronic obstructive pulmonary disease. Several techniques are currently being investigated, including implantation of devices into the lung and instillation of hot water vapor or polymer. This article reviews the spectrum of radiologic manifestations on chest radiography and CT that occur after the intervention. CONCLUSION. Familiarity with the intended effects and adverse events will aid the radiologist in supporting bronchoscopic lung volume reduction.
Medizinische Klinik, 1988
Radiology, 1991
If you really want to be smarter, reading can be one of the lots ways to evoke and realize. Many ... more If you really want to be smarter, reading can be one of the lots ways to evoke and realize. Many people who like reading will have more knowledge and experiences. Reading can be a way to gain information from economics, politics, science, fiction, literature, religion, and many others. As one of the part of book categories, thoracic radiology always becomes the most wanted book. Many people are absolutely searching for this book. It means that many love to read this kind of book.
Rontgen-Blatter; Zeitschrift fur Rontgen-Technik und medizinisch-wissenschaftliche Photographie, 1985
We examined, out of a total of 539 gastrectomies, 50 suture insufficiencies in respect of localis... more We examined, out of a total of 539 gastrectomies, 50 suture insufficiencies in respect of localisation and size, period elapsed since surgery, and duration of manifestation. The quality of the examination was assessed and compared with the diagnostic information supplied. Only 70% of the insufficiencies were detected within the first five days. A leak can occur as late as one month after surgery (maximum period). One-quarter of the insufficiencies were detected during repeat examinations. Hence, the indication for further follow-up checks should be liberal if there is any clinical suspicion. Insufficiencies of oesophagojejunal anastomosis predominate (37). These are followed by the insufficiencies of the blind closed jejunum loop. There is no noticeable influence of the quality of examination (within the range of variation at our institute) on the diagnosis of the insufficiency.
DMW - Deutsche Medizinische Wochenschrift
17. Hämophilie-Symposion, 1988
Mit der Einfuhrung der Faktor VIII-Hochkonzentrate Ende der 60er Jahre sowie der Heimselbstbehand... more Mit der Einfuhrung der Faktor VIII-Hochkonzentrate Ende der 60er Jahre sowie der Heimselbstbehandlung Mitte der 70er Jahre konnte die Entstehung der hamophilen Arthropathie wesentlich verlangsamt werden.
Radiology, 1996
To determine whether radiographically proved calcifications in core biopsy specimens are better p... more To determine whether radiographically proved calcifications in core biopsy specimens are better preserved in a nonaqueous fixative than in aqueous solutions. One hundred fifty core biopsy specimens were taken from two female breast specimens that had been preserved in ethanol. Forty-one of the specimens with radiographically proved microcalcifications were divided into four groups and deposited in four different solutions: 10% formaldehyde, 0.9% sodium chloride, electrolyte solution, and 74.1% ethanol with 10% 2-propanol. The core specimens were radiographed again after 1 and 3 days. Five ethanol-preserved specimens were also reexamined radiographically after 2 weeks. Within 3 days, total radiographic disappearance of microcalcifications was observed in all core biopsy specimens that were immersed in solutions with high water content. In those core specimens preserved in ethanol, microcalcifications showed no change. A nonaqueous fixative, such as ethanol, is a better preservative o...
Strahlentherapie und Onkologie : Organ der Deutschen Röntgengesellschaft ... [et al], 1990
Port films in radiation therapy suffer from low image contrast und exposure errors. We examined t... more 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.
Radiology, 1992
To determine the impact of reduced hard-copy size on diagnostic performance of digital radiograph... more To determine the impact of reduced hard-copy size on diagnostic performance of digital radiography, screen-film chest radiographs were compared with isodose digital storage phosphor radiographs in the detection of simulated nodules, fine pulmonary lines, and micronodular opacities superimposed on the chests of 10 healthy volunteers. Digital radiographs were laser-printed in a full-size conventional format and in image lengths of two-thirds, one-half, and five-elevenths of the conventional format. Eighteen thousand observations by eight radiologists were analyzed by use of receiver operating characteristics. The detectability of lines and micronodular opacities decreased with declining image format size. In the detection of micronodular opacities, only the nearly full-size digital images were equivalent to conventional images. In the detection of linear opacities, reduction of image length by one-half or more reduced performance (analysis of variance, P less than .05). Only for the d...
RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren, 1994
ABSTRACT
RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren, 1986
RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren, 1989
Technologies and performance of digital projection radiography are reviewed. Storage phosphor ima... more Technologies and performance of digital projection radiography are reviewed. Storage phosphor imaging plates can be used in existing diagnostic equipment and the resulting digital images permit the recognition of fine interstitial changes, if a high frequency edge enhancement is performed. While a generalized enhancement of low and medium spatial frequencies and a grey scale reversal do not improve the detectability of pulmonary nodules, selective enhancement of low frequencies in the mediastinal and retro-diaphragmatic areas may well improve diagnostic performance. Dose can be reduced if the resulting signal-to-noise ratio is adequate for diagnosis. Further dose savings can be achieved by the reduced number of retakes. Dual energy techniques improve the detectability and differential diagnosis of pulmonary nodules. The further development of picture archiving and communication systems (PACS) will turn the digital projection radiography into the method of choice for the diagnosis of chest disease.
RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren, 2006
British journal of …, 2000
Radiology, 1994
A guiding attachment is described that transforms a conventional magnetic resonance (MR) imaging ... more A guiding attachment is described that transforms a conventional magnetic resonance (MR) imaging surface coil into a stereotaxic biopsy unit. Eight patients, aged 38-66 years (mean, 54 years), with suspect breast lesions detected exclusively at contrast material-enhanced MR ...
RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren, 2002
Ziel: Das Ziel der vorliegenden Studie war die alters-und geschlechtsspezifische Analyse der mech... more Ziel: Das Ziel der vorliegenden Studie war die alters-und geschlechtsspezifische Analyse der mechanischen Eigenschaften und der Knochenmineraldichte (BMD) des proximalen Humerus in verschiedenen Höhen und Regionen. Methoden: Folgende Verfahren wurden angewandt: Mechanische Indentation Testung, DXA, QCT, pQCT und die Radiogrammmetrie (Cortical Index, CI). Die Untersuchungen wurden an 70 frischen Humeri von 46 humanen Präparaten (23 weiblich, 23 männlich; Alter median: 70,5 Jahre) durchgeführt. Ergebnisse: In der Gruppe der weiblichen Humeri fand sich eine hohe Korrelation zwischen Alter und Knochenmineraldichte (r =-0,62 to-0,70 p < 0,01) mit statistisch signifikanten Unterschieden zwischen Präparaten jünger als 69 Jahre und älter als 70 Jahre (p < 0.05). In der Gruppe der weiblichen Präparate mit einem Alter über 70 Jahre waren die Knochenmineraldichtewerte im Vergleich mit den männlichen Präparaten signifikant niedriger (p < 0.05). Unabhängig vom Alter der Präparate wurde die höchste Knochenmineraldichte und Knochenfestigkeit im proximalen Abschnitt und in den medialen und dorsalen Regionen des proximalen Humerus nachgewiesen. Schlussfolgerung: Die Ergebnisse geben Aufschluss über die Frakturentstehung und stellen die Grundlage für die Entwicklung von strukturorientierten Implantaten mit einer verbesserten Implantatfixation im osteoporotischen Knochen dar.
Journal of Experimental & Clinical Medicine, 1990
RadioGraphics, 1994
The combination of computed radiography (CR) and advanced multiple beam equalization radiography ... more The combination of computed radiography (CR) and advanced multiple beam equalization radiography (AMBER) was evaluated for both single- and dual-energy chest radiography. The improved signal-to-noise ratio found with CR and AMBER resulted in a better visualization of structures in the mediastinum and basal lung than that found with CR alone. For the central lung, no improvement was seen. Because of the compressed dynamic range with CR and AMBER, contrast on hard copies and video monitors could be high without a sacrifice in image latitude. Dual-energy images showed a considerably lower noise level. The combined use of AMBER and CR promises to overcome the dynamic range limitations of digital displays while improving signal-to-noise ratio.
AJR. American journal of roentgenology, 2015
OBJECTIVE. Bronchoscopic lung volume reduction promises to become an effective treatment option i... more OBJECTIVE. Bronchoscopic lung volume reduction promises to become an effective treatment option in severe chronic obstructive pulmonary disease. Several techniques are currently being investigated, including implantation of devices into the lung and instillation of hot water vapor or polymer. This article reviews the spectrum of radiologic manifestations on chest radiography and CT that occur after the intervention. CONCLUSION. Familiarity with the intended effects and adverse events will aid the radiologist in supporting bronchoscopic lung volume reduction.
Medizinische Klinik, 1988
Radiology, 1991
If you really want to be smarter, reading can be one of the lots ways to evoke and realize. Many ... more If you really want to be smarter, reading can be one of the lots ways to evoke and realize. Many people who like reading will have more knowledge and experiences. Reading can be a way to gain information from economics, politics, science, fiction, literature, religion, and many others. As one of the part of book categories, thoracic radiology always becomes the most wanted book. Many people are absolutely searching for this book. It means that many love to read this kind of book.
Rontgen-Blatter; Zeitschrift fur Rontgen-Technik und medizinisch-wissenschaftliche Photographie, 1985
We examined, out of a total of 539 gastrectomies, 50 suture insufficiencies in respect of localis... more We examined, out of a total of 539 gastrectomies, 50 suture insufficiencies in respect of localisation and size, period elapsed since surgery, and duration of manifestation. The quality of the examination was assessed and compared with the diagnostic information supplied. Only 70% of the insufficiencies were detected within the first five days. A leak can occur as late as one month after surgery (maximum period). One-quarter of the insufficiencies were detected during repeat examinations. Hence, the indication for further follow-up checks should be liberal if there is any clinical suspicion. Insufficiencies of oesophagojejunal anastomosis predominate (37). These are followed by the insufficiencies of the blind closed jejunum loop. There is no noticeable influence of the quality of examination (within the range of variation at our institute) on the diagnosis of the insufficiency.
DMW - Deutsche Medizinische Wochenschrift
17. Hämophilie-Symposion, 1988
Mit der Einfuhrung der Faktor VIII-Hochkonzentrate Ende der 60er Jahre sowie der Heimselbstbehand... more Mit der Einfuhrung der Faktor VIII-Hochkonzentrate Ende der 60er Jahre sowie der Heimselbstbehandlung Mitte der 70er Jahre konnte die Entstehung der hamophilen Arthropathie wesentlich verlangsamt werden.
Radiology, 1996
To determine whether radiographically proved calcifications in core biopsy specimens are better p... more To determine whether radiographically proved calcifications in core biopsy specimens are better preserved in a nonaqueous fixative than in aqueous solutions. One hundred fifty core biopsy specimens were taken from two female breast specimens that had been preserved in ethanol. Forty-one of the specimens with radiographically proved microcalcifications were divided into four groups and deposited in four different solutions: 10% formaldehyde, 0.9% sodium chloride, electrolyte solution, and 74.1% ethanol with 10% 2-propanol. The core specimens were radiographed again after 1 and 3 days. Five ethanol-preserved specimens were also reexamined radiographically after 2 weeks. Within 3 days, total radiographic disappearance of microcalcifications was observed in all core biopsy specimens that were immersed in solutions with high water content. In those core specimens preserved in ethanol, microcalcifications showed no change. A nonaqueous fixative, such as ethanol, is a better preservative o...
Strahlentherapie und Onkologie : Organ der Deutschen Röntgengesellschaft ... [et al], 1990
Port films in radiation therapy suffer from low image contrast und exposure errors. We examined t... more 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.
Radiology, 1992
To determine the impact of reduced hard-copy size on diagnostic performance of digital radiograph... more To determine the impact of reduced hard-copy size on diagnostic performance of digital radiography, screen-film chest radiographs were compared with isodose digital storage phosphor radiographs in the detection of simulated nodules, fine pulmonary lines, and micronodular opacities superimposed on the chests of 10 healthy volunteers. Digital radiographs were laser-printed in a full-size conventional format and in image lengths of two-thirds, one-half, and five-elevenths of the conventional format. Eighteen thousand observations by eight radiologists were analyzed by use of receiver operating characteristics. The detectability of lines and micronodular opacities decreased with declining image format size. In the detection of micronodular opacities, only the nearly full-size digital images were equivalent to conventional images. In the detection of linear opacities, reduction of image length by one-half or more reduced performance (analysis of variance, P less than .05). Only for the d...
RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren, 1994
ABSTRACT
RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren, 1986
RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren, 1989
Technologies and performance of digital projection radiography are reviewed. Storage phosphor ima... more Technologies and performance of digital projection radiography are reviewed. Storage phosphor imaging plates can be used in existing diagnostic equipment and the resulting digital images permit the recognition of fine interstitial changes, if a high frequency edge enhancement is performed. While a generalized enhancement of low and medium spatial frequencies and a grey scale reversal do not improve the detectability of pulmonary nodules, selective enhancement of low frequencies in the mediastinal and retro-diaphragmatic areas may well improve diagnostic performance. Dose can be reduced if the resulting signal-to-noise ratio is adequate for diagnosis. Further dose savings can be achieved by the reduced number of retakes. Dual energy techniques improve the detectability and differential diagnosis of pulmonary nodules. The further development of picture archiving and communication systems (PACS) will turn the digital projection radiography into the method of choice for the diagnosis of chest disease.
RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren, 2006
British journal of …, 2000
Radiology, 1994
A guiding attachment is described that transforms a conventional magnetic resonance (MR) imaging ... more A guiding attachment is described that transforms a conventional magnetic resonance (MR) imaging surface coil into a stereotaxic biopsy unit. Eight patients, aged 38-66 years (mean, 54 years), with suspect breast lesions detected exclusively at contrast material-enhanced MR ...