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[en] This book examines medical diagnostic techniques. Topics considered include biological considerations in the approach to clinical medicines; infectious diseases; disorders of the heart; disorders of the vascular system; disorders of the respiratory system; diseases of the kidneys and urinary tract; disorders of the alimentary tract; disorders of the hepatobiliary system and pancreas; disorders of the hematopoietic system; disorders of bone and bone mineralization; disorders of the joints, connective tissues, and striated muscles; disorders of the nervous system; miscellaneous disorders; and procedures in diagnostic imaging
[en] Vertebral fractures are the hallmark of osteoporosis and are associated with increased morbility and mortality. Because a majority of vertebral fractures often occur in absence of specific trauma and are asymptomatic, their identification is radiographic. The two most widely used methods to determine the severity of vertebral fractures are the visual semiquantitative (SQ) assessment and the morphometric quantitative approach, involving the measurements of vertebral body heights. The measurements may be made on conventional spinal radiographs (MRX: morphometric X-ray radiography) or on images obtained from dual X-ray absorptiometry (DXA) scans (MXA: morphometric X-ray absorptiometry).The availability of a rapid, low-dose method for assessment of vertebral fractures, using advanced fan-beam DXA devices, provides a practical method for integrated assessment of BMD and vertebral fracture status. The visual or morphometric assessment of lateral DXA spine images may have a potential role for use as a prescreening tool, excluding normal subjects prior to performing conventional radiographs. (orig.)
[en] For improving the image quality in case of neck Lateral projections, the AI compensation filter were used and conclusion that, it could be got the high image quality able to observe the shadow of cervical spine, hyoid bone, trachea, soft tissue simultaneously
[en] The stimulus for this investigation concerning radiation exposure during radiography of the spine, particularly in children with scoliosis, is the fact that there are no data in the literature. In 16 series of measurements we studied the effect of grids, kilovoltage, focus-film distance and film-screen systems using dosimeters. The use of grids led to a 5-7 times increase in radiation dose compared with exposures without grids. For this reason grids are not recommended for serial examinations in cases of scoliosis. It is easier to evaluate the spine on a single large film than on several small films and radiation dose is also halved. Therefore, the use of large single films is recommended, particularly for children and adolescents. (orig.)
[de]Fragen zur Strahlenexposition bei Wirbelsaeulenaufnahmen, besonders bei Kindern mit Skoliose, gaben den Anstoss fuer diese Untersuchung, weil aus dem aktuellen Schrifttum hierueber keine Daten bekannt sind. In 16 Messreihen wurde der Einfluss von Raster, Aufnahmespannung, Fokus-Film-Abstand und Film-Folien-System auf die Strahlenexposition mit Diagnostikdosimetern untersucht. Die Verwendung eines Rasters fuehrt zu einer 5- bis 7mal hoeheren Strahlenbelastung als Aufnahmen ohne Raster. Darum werden fuer Verlaufskontrollen bei der Fragestellung Wirbelsaeulenstatik Aufnahmen ohne Raster empfohlen. Da die Beurteilung der Wirbelsaeulenstatik auf Ganzaufnahmen (20/60 oder ggf. 30/90) gegenueber Teilaufnahmen (2 x 20/40) der Wirbelsaeule einfacher ist und die Strahlenexposition etwa um die Haelfte niedriger liegt, empfiehlt sich besonders bei Jugendlichen und Kindern fuer diese Fragestellung die Bevorzugung von Ganzaufnahmen der Wirbelsaeule. (orig.)
[en] The purpose of this study was to evaluate a new technique for localizing impacted mesiodens using its horizontal magnification ratio on panoramic radiographs. Location-magnification equation of a panoramic equipment was obtained from horizontal magnification ratio of a metal ball which was located variable positions from the center of image layer at interval of 2 mm. Panoramic radiographs were obtained from a skull phantom with a metal ball which was a substitute for impacted mesiodens and was embedded 10 mm (Group 1), 15 mm (Group 2), and 20 mm (Group 3) posterior to the central incisor. Each group obtained 7 panoramic radiographs at variable positions and one periapical radiograph. Three methods were used to estimate the actual width of the incisors and the balls which were used to calculate the magnification ratio. The methods included using the actual incisor width and the calculated ball width (Method 1), using the actual incisor width and the ball widths measured on periapical radiograph (Method 2), and using the incisor and the ball widths measured on periapical radiograph (Method 3). The location of the metal ball was calculated by using the location-magnification equation. The smallest difference between the calculated and the actual distance was 0.1±0.7 mm in Group 1/Method 3. The largest difference was -4.2±1.6 mm in Group 3/Method 2. In all groups, method 3 was the most accurate. Quantitative localization of impacted mesiodens is possible by using panoramic radiograph.
[en] Incorrect exposure of conventional radiographs frequently leads to repetition of the examination and thereby to increased radiation exposure for the patient. Underexposed films of an Alderson-Rando phantom, an ankle joint and a patella were digitised by means of an inexpensive fluorescent light scanner, and subsequent image manipulation improved quality so as to make the image diagnostically adequate. For the demonstration of markedly underexposed structures digitalisation with subsequent contrast enhancement was used. Well exposed structures are best evaluated in contrast enhanced transmitted light. Our results suggest it should be possible to reduce the number of repeat exposures and thereby to limit radiation exposure. (orig.)
[de]Fehlbelichtungen in der konventionellen Roentgendiagnostik fuehren haeufig zu Wiederholungsaufnahmen und damit zu erneuten Strahlenexpositionen der Patienten. Anhand von Aufnahmen eines Alderson-Rando-Phantoms, Aufnahmen des Sprunggelenkes und der Patella wurde gezeigt, dass stark unterbelichtete Aufnahmen durch die Filmdigitalisierung mittels eines kostenguenstigen Fluoreszenzlichtscanners und anschliessende Bildnachbearbeitung so weit verbessert werden koennen, dass sie noch diagnostisch verwertbar sind. Fuer die Darstellung von stark unterbelichteten Strukturen eignet sich die Digitalisierung in Auflichttechnik mit nachfolgender Kontrastverstaerkung. Dagegen sind gut belichtete Strukturen am besten im kontrastverstaerkten Durchlichtbild zu beurteilen. Unsere Ergebnisse lassen eine erhebliche Verringerung der Wiederholungsaufnahmen und eine Reduktion der Strahlenbelastung bei geringen Investitionskosten erwarten. (orig.)
[en] The purpose of this study was to investigate appropriate contrast reference values (CRVs) by comparing the contrast in phantom and clinical images. Phantom contrast was measured using two methods: (1) counting the number of visible pits of different depths in an aluminum plate, and (2) obtaining the contrast-to-noise ratio (CNR) for 5 tissue-equivalent materials (porcelain, aluminum, polytetrafluoroethylene [PTFE], polyoxymethylene [POM], and polymethylmethacrylate [PMMA]). Four panoramic radiographs of the contrast phantom, embedded in the 4 different regions of the arch-form stand, and 1 real skull phantom image were obtained, post-processed, and compared. The clinical image quality evaluation chart was used to obtain the cut-off values of the phantom CRV corresponding to the criterion of being adequate for diagnosis. The CRVs were obtained using 4 aluminum pits in the incisor and premolar region, 5 aluminum pits in the molar region, and 2 aluminum pits in the temporomandibular joint (TMJ) region. The CRVs obtained based on the CNR measured in the anterior region were: porcelain, 13.95; aluminum, 9.68; PTFE, 6.71; and POM, 1.79. The corresponding values in the premolar region were: porcelain, 14.22; aluminum, 8.82; PTFE, 5.95; and POM, 2.30. In the molar region, the following values were obtained: porcelain, 7.40; aluminum, 3.68; PTFE, 1.27; and POM, - 0.18. The CRVs for the TMJ region were: porcelain, 3.60; aluminum, 2.04; PTFE, 0.48; and POM, - 0.43. CRVs were determined for each part of the jaw using the CNR value and the number of pits observed in phantom images
[en] Jarcho-Levin syndrome (JLS) is a rare congenital dysostosis characterized by multiple vertebral and costal anomalies. The combination of JLS and neural tube defect is rare. Only six cases of JLS accompanying diastematomyelia have been reported; all were in infants or children. We present the case of a 37-year-old female patient with JLS who also had diastematomyelia in lumbar vertebral level. This is the seventh case of JLS with diastematomyelia, and the first adult case.
[en] Clinical examination, photometric evaluation, and radiographic analysis have been used to evaluate the asymmetry of the face. Commonly used skull radiographs to assess skeletal asymmetry include postero-anterior cephalometrics, submentovertex view, and panoramic view. The purpose of this study is the comparison of the reliance of the postero-anterior cephalometric view, submentovertex view, and panoramic view in the asymmetric group. The measurements are MSL (midsagittal plane)-Co, MSL-Go, MSK-Me, MSL-Al, MSL-Bl, Mn. ramus Height (Co-Go), Mn. Body Length (Go-Me), and Total Mn. Length (Co-Mr). The results were as follows: 1. The lack of either a right-sided of left-sided asymmetric dominant was found. 2. The postero-anterior cephalometric view and submentovertex view relatively agreed with each other in the result. The postero-anterior cephalometric view and submentovertex view had the clinical reliability and effectiveness in the diagnosis of the skeletal asymmetry (p<0,05).3. The panoramic view showed more magnification compared to the other radiographs. In the vertical measurements the panoramic view had clinical reliability relatively (p<0.05). But we cannot rely on the horizontal measurements in the panoramic view (p<0.05).