[en] Objectives: Lesions of the major salivary glands represent a heterogeneous group comprising infectious, autoimmune, and neoplastic disorders. The reliable pre-operative assessment of the lesional dignity might reduce patient's morbidity preventing re-surgery. To date, there exists no imaging technique which reliably distinguishes tumour entities. Methods: 35 parotid lesions were analysed in this study. B-mode ultrasound, colour duplex imaging and contrast enhanced ultrasound were applied for all patients. After fractionated boli of 4.8 ml SonoVue^® perfusion kinetics, time to peak (TP) and mean transit time (MTT), were analysed for intraparotideal lesion and were normalised by circumjacent parotid tissue. Ultrasonographic data was structured in a multimodal diagnostic pathway. Results: B-mode ultrasound identifies six lymphoepithelial lesions due to Sjoegren's syndrome (p: 0.0001). CDS further differentiates hypovascularised pleomorphic adenoma from hypervascularised Warthin's tumours, monomorphic adenomas, and carcinomas (p < 0.0001). Application of CEUS detected Warthin's tumours being significantly hypervascularised compared to monomorphic adenomas (MTT, p < 0.05) and carcinomas (MTT, p < 0.02). Conclusions: A multimodal diagnostic pathway unifies different ultrasonographic techniques and identifies pleomorphic adenomas, Warthin's tumours and carcinomas with sensitivities of 100%. Further studies have to be performed to validate this diagnostic approach and to specify monomorphic adenomas.

[en] The purpose of the present study was to investigate the degree and clinical relevance of synovitis in craniomandibular dysfunction. In total, 140 temporomandibular joints were examined using a 3 T MRI scanner. Quantitative analysis of synovial enhancement was performed and interrelated with arthrosis deformans, degenerative disc disease, joint effusion, bone marrow edema and restriction of motion. We found a statistically high and significant correlation between the degenerative changes as mentioned above and the intensity of synovial enhancement. The study shows that typical MRI findings in CMD patients are often combined with signs of synovitis. Presumably joint inflammation has an effect on the clinical signs and symptoms and also the prognosis of CMD. These results should be taken into consideration when selecting treatment.

[en] Purpose: To simulate and optimize a MR protocol for squamous cell cancer of the head and neck (HNSCC) patients for potential future use in an integrated whole-body MR–PET scanner. Materials and methods: On a clinical 3T scanner, which is the basis for a recently introduced fully integrated whole-body MR–PET, 20 patients with untreated HNSCC routinely staged with 18F-FDG PET/CT underwent a dedicated MR protocol for the neck. Moreover, a whole-body Dixon MR-sequence was applied, which is used for attenuation correction on a recently introduced hybrid MR–PET scanner. In a subset of patients volume-interpolated-breathhold (VIBE) T1w-sequences for lungs and liver were added. Total imaging time was analyzed for both groups. The quality of the delineation of the primary tumor (scale 0–3) and the presence or absence of lymph node metastases (scale 1–5) was evaluated for CT, MR, PET/CT and a combination of MR and PET to ensure that the MR–PET fusion does not cause a loss of diagnostic capability. PET was used to identify distant metastases. The PET dataset for simulated MR/PET was based on a segmentation of the CT data into 4 classes according to the approach of the Dixon MR-sequence for MR–PET. Standard of reference was histopathology in 19 cases. In one case no histopathological confirmation of a primary tumor could be achieved. Results: Mean imaging time was 35:17 min (range: 31:08–42:42 min) for the protocol including sequences for local staging and attenuation correction and 44:17 min (range: 35:44–54:58) for the extended protocol. Although not statistically significant a combination of MR and PET performed better in the delineation of the primary tumor (mean 2.20) compared to CT (mean 1.40), MR (1.95) and PET/CT (2.15) especially in patients with dental implants. PET/CT and combining MR and PET performed slightly better than CT and MR for the assessment of lymph node metastases. Two patients with distant metastases were only identified by PET. Conclusion: We established a potential MR-protocol to be used for HNSCC patients in a recently introduced MR–PET scanner. The proposed protocol can be performed in an acceptable time frame and did not lead to a loss of diagnostic capability compared to PET/CT

[en] Recently it has been shown that radiation induces migration of glioma cells and facilitates a further spread of tumor cells locally and systemically. The aim of this study was to evaluate whether radiotherapy induces migration in head and neck squamous cell carcinoma (HNSCC). A further aim was to investigate the effects of blocking the epidermal growth factor receptor (EGFR) and its downstream pathways (Raf/MEK/ERK, PI3K/Akt) on tumor cell migration in vitro. Migration of tumor cells was assessed via a wound healing assay and proliferation by a MTT colorimeritric assay using 3 HNSCC cell lines (BHY, CAL-27, HN). The cells were treated with increasing doses of irradiation (2 Gy, 5 Gy, 8 Gy) in the presence or absence of EGF, EGFR-antagonist (AG1478) or inhibitors of the downstream pathways PI3K (LY294002), mTOR (rapamycin) and MEK1 (PD98059). Biochemical activation of EGFR and the downstream markers Akt and ERK were examined by Western blot analysis. In absence of stimulation or inhibition, increasing doses of irradiation induced a dose-dependent enhancement of migrating cells (p < 0.05 for the 3 HNSCC cell lines) and a decrease of cell proliferation (p < 0.05 for the 3 HNSCC cell lines). The inhibition of EGFR or the downstream pathways reduced cell migration significantly (almost all p < 0.05 for the 3 HNSCC cell lines). Stimulation of HNSCC cells with EGF caused a significant increase in migration (p < 0.05 for the 3 HNSCC cell lines). After irradiation alone a pronounced activation of EGFR was observed by Western blot analysis. Our results demonstrate that the EGFR is involved in radiation induced migration of HNSCC cells. Therefore EGFR or the downstream pathways might be a target for the treatment of HNSCC to improve the efficacy of radiotherapy