[Unusual presentation of a Langerhans cell histiocytosis]. / Ungewöhnliche Präsentation einer Langerhans-Zell-Histiozytose.

A 16-month-old male infant was presented with swelling of the left upper eye lid 4 weeks after a blunt orbital trauma. A prolonged hematoma was suspected and the child was discharged with an appointment 4 weeks later. However, the child was presented again with progressive swelling of the lid 10 days later. Magnetic resonance imaging (MRI) showed a tumor extending from the frontal bone to the anterior cranial fossa and into the orbit. An incisional biopsy led to the diagnosis of orbital Langerhans cell histiocytosis and systemic therapy led to complete remission of the tumor. Prolonged periorbital swelling must always prompt further diagnostics even when patients present with a history of trauma.

Volume measurement of liver metastases using multidetector computed tomography: comparison of lesion diameter and volume segmentation - a phantom study.

PURPOSE: To compare lesion volume determination by applying diameter measurement and three different segmentation algorithms at different slice thicknesses reconstructed from computed tomography (CT) of a phantom model for hepatic colorectal metastases. MATERIALS AND METHODS: Based on CT attenuation measurements obtained retrospectively from 20 patients with colorectal liver metastases, a phantom model was designed with a sponge soaked with a dilution of contrast agent and 6 embedded polyamide spheres (diameter, 8 - 30 mm) to simulate the contrast behavior of liver metastases. CT scans were obtained and reconstructed at different slice thicknesses (0.625/1.25/2.5/3.75 mm; increment, 1). One observer performed software-aided volume determination using the maximum diameter, manual segmentation, seed point method, and threshold method six times for each lesion in a randomized order. Statistical analysis revealed the absolute and relative differences from the actual lesion volumes and the intraobserver differences as well as the influence of slice thickness for each method. RESULTS: The mean relative differences of the seed point method (1.2 - 5.9%) and manual segmentation (2.6 - 4.9%) were significantly lower than the threshold method (5.4 - 12.8%) and diameter measurement (12.3 - 18.5%; p < 0.01). Volume determination by manual segmentation and the seed point method benefited from the use of thin-slice CT datasets. The intraobserver variation was lowest when using the manual segmentation (1.5 - 3.3%) and the seed point method (2.2 - 3.9%; p < 0.001). CONCLUSION: Manual segmentation and the seed point method for thin CT slices were the methods with the lowest volume differences and intraobserver variation.

[Comparison of magnetic resonance imaging signs and clinical findings in follow-up examinations in children and juveniles with temporomandibular joint involvement in juvenile idiopathic arthritis]. / Vergleich magnetresonanztomografischer und klinischer Befunde von Follow-up-Untersuchungen bei Kindern und Jugendlichen mit rheumatischer Temporomandibulararthritis.

PURPOSE: The aim of this study was to analyze the extent to which pathological findings of temporomandibular joint (TMJ) in magnetic resonance imaging (MRI) follow-up examinations are correlated with clinical symptoms in patients with TMJ involvement in juvenile idiopathic arthritis (JIA) over time. MATERIALS AND METHOD: Data from 34 patients with TMJ involvement in JIA was retrospectively examined. Shortly after two clinical examinations, the first MRI and the follow-up MRI were performed. The MRI examinations took place with 1.5 T MRI. RESULTS: In both MRI examinations alterations on the condyle (MRI1: 88 %, MRT2: 91 %) and contrast enhancement (MRT1: 76 %, MRT2 65 %) were found most frequently. TMJ pain (65 %) and lower mouth opening capacity (65 %) were the number one finding in the first clinical examination. A statistically significant correlation was found between the alterations on the condyle and TMJ pain (p = 0.025) and between the alterations on the condyle and lower mouth opening capacity (p = 0.019). By comparing the results of the first MRI with the results of the follow-up MRI, we identified a trend towards a progression of TMJ arthritis, while the clinical follow-up showed an improvement in most patients. CONCLUSION: We found a discrepancy between the progressive or stable trends of pathological findings in follow-up MRI and the decrease in clinical symptoms over time. Therefore, follow-up examination by MRI shows important information for correct evaluation about the stage of TMJ arthritis and about the need for treatment. Consequently, follow-up examination by MRI is an appropriate addition to clinical examination in the therapeutic concept.