[Urticaria multiforme: difficult to distinguish from other skin conditions]. / Urticaria multiforme.

BACKGROUND: Urticaria multiforme is a rare clinical variant of urticaria that occurs specifically in children. CASE DESCRIPTION: A boy aged 11 months was presented at the Emergency Department with acute onset of itching urticarial skin weals and acral oedema. This picture is consistent with the diagnosis of urticaria multiforme. CONCLUSION: The diagnosis of urticaria multiforme can be made on the basis of the clinical picture. Treatment is symptomatic and in most cases this condition resolves spontaneously within two weeks. It is often confused with erythema exsudativum multiforme, urticarial vasculitis, a serum sickness-like reaction or acute haemorrhagic oedema of infancy (AHOI syndrome). As each of these clinical presentations involves specific treatment and prognosis, it is important to be able to distinguish between them.

Automatic detection system for multiple region of interest registration to account for posture changes in head and neck radiotherapy.

Despite immobilization of head and neck (H and N) cancer patients, considerable posture changes occur over the course of radiotherapy (RT). To account for the posture changes, we previously implemented a multiple regions of interest (mROIs) registration system tailored to the H and N region for image-guided RT correction strategies. This paper is focused on the automatic segmentation of the ROIs in the H and N region. We developed a fast and robust automatic detection system suitable for an online image-guided application and quantified its performance. The system was developed to segment nine high contrast structures from the planning CT including cervical vertebrae, mandible, hyoid, manubrium of sternum, larynx and occipital bone. It generates nine 3D rectangular-shaped ROIs and informs the user in case of ambiguities. Two observers evaluated the robustness of the segmentation on 188 H and N cancer patients. Bland-Altman analysis was applied to a sub-group of 50 patients to compare the registration results using only the automatically generated ROIs and those manually set by two independent experts. Finally the time performance and workload were evaluated. Automatic detection of individual anatomical ROIs had a success rate of 97%/53% with/without user notifications respectively. Following the notifications, for 38% of the patients one or more structures were manually adjusted. The processing time was on average 5 s. The limits of agreement between the local registrations of manually and automatically set ROIs was comprised between ±1.4 mm, except for the manubrium of sternum (-1.71 mm and 1.67 mm), and were similar to the limits agreement between the two experts. The workload to place the nine ROIs was reduced from 141 s (±20 s) by the manual procedure to 59 s (±17 s) using the automatic method. An efficient detection system to segment multiple ROIs was developed for Cone-Beam CT image-guided applications in the H and N region and is clinically implemented in our department.