High-Pitch Computed Tomography Coronary Angiography—A New Dose-Saving Algorithm: Estimation of Radiation Exposure

Purpose. To estimate effective dose and organ equivalent doses of prospective ECG-triggered high-pitch CTCA. Materials and Methods. For dose measurements, an Alderson-Rando phantom equipped with thermoluminescent dosimeters was used. The effective dose was calculated according to ICRP 103. Exposure was performed on a second-generation dual-source scanner (SOMATOM Definition Flash, Siemens Medical Solutions, Germany). The following scan parameters were used: 320 mAs per rotation, 100 and 120 kV, pitch 3.4 for prospectively ECG-triggered high-pitch CTCA, scan range of 13.5 cm, collimation 64 × 2 × 0.6 mm with z-flying focal spot, gantry rotation time 280 ms, and simulated heart rate of 60 beats per minute. Results. Depending on the applied tube potential, the effective whole-body dose of the cardiac scan ranged from 1.1 mSv to 1.6 mSv and from 1.2 to 1.8 mSv for males and females, respectively. The radiosensitive breast tissue in the range of the primary beam caused an increased female-specific effective dose of 8.6%±0.3% compared to males. Decreasing the tube potential, a significant reduction of the effective dose of 35.8% and 36.0% can be achieved for males and females, respectively (P < 0.001). Conclusion. The radiologist and the CT technician should be aware of this new dose-saving strategy to keep the radiation exposure as low as reasonablly achievable

Computer-based Quantification of the Achilles tendon thickness and morphology in B-mode US images

B-mode Ultraschall ist ein etabliertes diagnostisches Verfahren zur qualitativen Analyse der Echotextur der Achillessehne. Dieses qualitative Verfahren scheint zwischen normalen und chronisch degenerierten Sehnen unterscheiden zu können, ist aber teilweise untersucherabhängig. Ziel: Ziel dieser Arbeit ist es ein quantitatives diagnostisches sonographisches Kriterium zu etablieren, welches durch automatische Analyse der Dicke und Sonomorphologie der Achillessehne zwischen gesunden und chronisch degenerierten Achillessehnen unterscheiden kann. Material und Methode: Eine Gesamtzahl von 59 Probanden wurden in die Studie eingeschlossen. Bei 24 Probanden bestand eine manifeste nicht-insertionale Tendinose. 35 Probanden zeigten keine sonographischen oder klinischen Zeichen einer Tendinopathie. Jedes US Bild wurde mit dem automatischen Analysesystem ausgewertet. Als Parameter wurden die maximale und die minimale Dicke sowie die maximale Krümmung der Kontur und zwei charakteristische Spektralmerkmale der Echotextur der Achillessehne in die Analyse integriert. Ergebnisse: Die automatische Bildauswertung zeigte für diese Querschnittsstudie signifikante Unterschiede im Bezug auf die Dicke und Sonomorphologie für degenerierte Sehnen im Vergleich zum Normalkollektiv. Mit Hilfe des automatischen Analysesystems wurde eine deutliche Reduktion der untersucherabhängigen Variabilität der Dickenmessung der Achillessehne erreicht. Schlussfolgerungen: Die automatische Auswertung von Dicke und Sonomorphologie der Achillessehne ist ein nützliches diagnostisches Verfahren zur Quantifizierung der Sehnendegeneration. In der weiteren Entwicklung könnte das hier vorgestellte Verfahren auch auf die Ultraschalluntersuchung andere sehnigen Strukturen (Patellasehne, Ultraschall der Schulter) sowie auf andere bildgebende Verfahren (Kernspin-, Computertomografie) angewendet werden.B-mode ultrasound (US) is an established diagnostic tool for qualitative analysis of Achilles tendon (AT) echo texture. This qualitative procedure might differentiate between normal and chronic degenerated tendons but is partly dependent on subjectivity of the reader. Purpose: The aim of this study is to establish a quantitative diagnostic sonographic criterion to differentiate between healthy and chronic degenerated AT by using an automatic analysing system of the AT echo texture in B- mode US images. Materials and Methods: A total of 59 subjects were included in the study. 24 subjects were affected by a manifest Achilles mid portion tendinosis. 35 subjects showed no sonographic or clinical signs of tendinopathia. Each US image was processed by an automatic analysing system. The maximum and the mean Achilles tendon thickness as well as the maximum flexion and two characteristic spectral features of the tendon echo texture were evaluated. Results: Automatic computational image processing showed for this cross-sectional study significant differences concerning thickness and sonomorphologic pattern of degenerated tendons compared to healthy tendons. By the aid of automatic image processing a reduction of observer dependent variability concerning thickness measurement was reached. Conclusion: Automatic detection of the Achilles tendon thickness and echo texture is a useful diagnostic tool to quantify tendon degeneration. In further studies this automatic process could be established for other orthopaedic ultrasound investigations (Patella tendon, ultrasound investigation of the shoulder) as well as other diagnostic imaging processes (MRI, CT)

Dendritic cell tumor in a salivary gland lymph node: a rare differential diagnosis of salivary gland neoplasms

Dendritic cell tumors are extremely rare neoplasms arising from antigen-presenting cells of the immune system. We report a case of a 69-year-old man with an unremarkable medical history who presented with a 2-months history of a gradually enlarging painless, firm, mobile, 2 × 2-cm swelling at the caudal pole of the left parotid gland without systemic symptoms. Histologically, the tumor consisted of a spindle cell proliferation in an intraparotideal lymph node. Based on the histopathologic, immunohistochemical and electron microscopic findings, a dendritic cell tumor, not otherwise specified (NOS) in an intraparotideal lymph node was diagnosed. The patient underwent complete tumor resection, and is currently free of disease, 2 years after surgery. These extremely rare tumors must be distinguished from other more common tumors in the salivary glands. Awareness that dendritic cell tumors may occur in this localization, careful histologic evaluation and ancillary immunohistochemical and electron microscopical analyses should allow for recognition of this entity. Virtual Slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1614859498581601