The value of MR-tomography in the diagnosis of occult fractures

The term “occult fracture” defines the lack of visible fracture signs in conventional radiography although a fracture exists. The diagnosis is made in the sequel or through further diagnostic procedures. The use of scintigraphy and CT examinations is limited by their moderate sensitivity and specificity. In contrast, MRI is a diagnostic tool that allows early diagnosis of a fracture and of accompanying chondral or ligament damage. We report on 23 patients with traumatic fractures at 5 different anatomical sites, all of which were negative by x-ray, but the diagnosis could subsequently be made with MRI.     

Neue biodegradable Polylactid-implantate (Polypin®-C) zur Therapie von Radiuskopffrakturen

Dislocated radial head fractures of the type Mason II are usually treated with screws and buttress plates. The implants are generally removed at a later date. Biodegradable implants can be applied successfully for the reduction of small radial head fractures subject to shearing forces and slight loads. The implants are completely absorbed once the fracture has healed, making a second operation for the removal of the implant unnecessary. The Polypin C-Pin is made of poly(L, DL-lactide) mixed with 10% beta-tricalcium phosphate to ensure controlled, slow degradation with no significant side effects. This new Polypin C fixation pin was clinically tested on 35 patients with radial head fractures (CCF 21B2.1 and 21B2.2) from 31.10.1996 until 1.4.2002. A total of 34 of the patients (97.1%) underwent a clinical and conventional radiological follow-up examination after an average of 38.2 months. In 29 cases a CT was also carried out. Between 18 and 24 months, two cases of grade 1 osteolysis were observed around the pin head. No trace of osteolysis was observed at the final examination in either case. According to the Broberg score, an average of 96 out of a possible 100 points were attained at the final examination (31 excellent, 2 good, 1 unsatisfactory). After a period of 24 months, the pins were no longer visible on a conventional x-ray. A CT evaluation showed a density similar to that of spongioid bone in the original pin cavities after 3 years. These excellent clinical results prove that the Polypin C is a good method to treat dislocated radial head fractures.     

Diagnostik der intraartikul?ren Tibiakopffraktur Eine prospektiv vergleichende Studie Eine prospektiv vergleichende Studie

Für die richtige Einsch?tzung der Tibiakopffraktur ist eine komplette Darstellung des Gelenkplateaus erforderlich. In einer prospektiven Untersuchung sollte die konventionellen Tomographie, die Computertomomographie (CT) und die Kernspintomographie (MRT) miteinander verglichen werden.     

Design and testing of artifact-suppressed adaptive histogram equalization: a contrast-enhancement technique for display of digital chest radiographs

One of the goals of our research in the field of digital radiography has been to develop contrast-enhancement algorithms for eventual use in the display of chest images on video devices with the aim of preserving the diagnostic information presently available with film, some of which would normally be lost because of the smaller dynamic range of video monitors. The ASAHE algorithm discussed in this article has been tested by investigating observer performance in a difficult detection task involving phantoms and simulated lung nodules, using film as the output medium. The results of the experiment showed that the algorithm is successful in providing contrast-enhanced, natural-looking chest images while maintaining diagnostic information. The algorithm did not effect an increase in nodule detectability, but this was not unexpected because film is a medium capable of displaying a wide range of gray levels. It is sufficient at this stage to show that there is no degradation in observer performance. Future tests will evaluate the performance of the ASAHE algorithm in preparing chest images for video display.