Mueller–Weiss syndrome: imaging and implications

Mueller–Weiss syndrome (MWS), or spontaneous osteonecrosis of the tarsal navicular in adults, is a rare cause of chronic medial midfoot pain. MWS has been described in orthopedic, podiatric, and radiologic literature without consensus agreement on its pathophysiology and treatment. We present the radiographic and magnetic resonance imaging of a case of MWS with reference to navicular biomechanical stressors and potential pathogenesis.     

Prof. Dr. Hans-Dieter Weiss zum Gedenken

Ohne Zusammenfassung     

Weiss lecture. The dose-rate factor in radiation biology.

The dose-rate effect has been the topic of extensive radiobiological studies and has important implications in radiation therapy and in the field of radiation protection. Three examples will be discussed: two in radiation therapy and one in protection. First, continuous low dose-rate interstitial brachytherapy may be replaced by pulsed brachytherapy, using a single source moving through the catheters of the implant. This strategy, using a modern computer-controlled afterloading device, would allow better dose optimization and result in a considerable cost saving. Radiobiological data have proved useful in defining the pulse length and pulse frequency that is equivalent to continuous low dose-rate. Second, in the intracavitary treatment of carcinoma of the cervix, a few high dose-rate (HDR) fractions on an outpatients basis can replace the low dose-rate (LDR) treatment that requires the patient to be hospitalized for several days. Radiobiological data can be used to estimate the dose levels at HDR that are equivalent to conventional LDR protocols. Third, it is usually assumed in radiation protection that doses accumulated over a period of time at low dose-rate are less effective biologically than the same dose delivered in a single acute exposure. While this may be true for X- or gamma-rays, radiobiological data indicate that neutrons delivered at low dose or in a series of fractions spread out over a period of time may produce more oncogenic transformation than a single acute exposure. This has important implications in radiation protection.     

Percutaneous decompression for the treatment of Mueller–Weiss syndrome

This report describes the case of a young athlete, who presented with a painful foot and was eventually diagnosed with early-stage Mueller–Weiss syndrome (spontaneous osteonecrosis of the navicular) by MRI. As non-operative management was unsuccessful, a percutaneous decompression of the navicular was performed. The patient made a full recovery and was able to return to her previous level of sporting activity. Subsequent imaging showed complete remodelling of the bony architecture of the affected navicular.     

Weiss lecture. Radiation chemistry: basic, strategic or tactical science?

The work of Weiss in the 1930s, particularly with Haber, has only recently been recognized to have implications in biology and medicine. Similarly, research in radiation chemistry and the application of the pulse radiolysis technique, for example, have implications far beyond traditional radiation chemistry. Some examples of such research are discussed against a background of categorization into 'basic', 'strategic' or 'tactical' science, rather than 'pure' and 'applied'. Examples discussed include redox properties of free radicals, which are now on a firm quantitative basis, and the identification and characterization of nitro radicals as intermediates in drug metabolism. Radical reactions often take place in multicomponent systems, and the techniques of radiation chemistry can be used to probe, for example, events occurring at interfaces in micelles. Industrial processes involving radiation are attracting investment, particularly in Japan. Radiation chemistry deserves further support to exploit its full potential, but much research using radiation chemical techniques often appears, probably more appropriately, under different labels.     

Preparing and Delivering Your Best Radiology Lecture

Delivering a presentation that is educational, memorable, and even inspiring is the aspiration of all speakers. Unfortunately, public speaking is an anxiety-producing experience for many. This is especially true when delivering a talk to physician colleagues. Like so many daunting activities, success is achievable if you are willing to invest the time and energy to prepare. We believe that adherence to the principles outlined in this article, including a focus on content, delivery and design, will help you to succeed.