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Suspected recurrence of thyroid carcinoma is a diagnostic challenge when findings of both a radio iodine whole body scan and ultrasound are negative. PET/CT and MRI have shown to be feasible for detection of recurrent disease. However, the added value of a consensus reading by the radiologist and the nuclear medicine physician, which has been deemed to be helpful in clinical routines, has not been investigated. This study aimed to investigate the impact of combined FDG-PET/ldCT and MRI on detection of locally recurrent TC and nodal metastases in high-risk patients with special focus on the value of the multidisciplinary consensus reading. Forty-six patients with suspected locally recurrent thyroid cancer or nodal metastases after thyroidectomy and radio-iodine therapy were retrospectively selected for analysis. Inclusion criteria comprised elevated thyroglobulin blood levels, a negative ultrasound, negative iodine whole body scan, as well as combined FDG-PET/ldCT and MRI examinations. Neck compartments in FDG-PET/ldCT and MRI examinations were independently analyzed by two blinded observers for local recurrence and nodal metastases of thyroid cancer. Consecutively, the scans were read in consensus. To explore a possible synergistic effect, FDG-PET/ldCT and MRI results were combined. Histopathology or long-term follow-up served as a gold standard. For method comparison, sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy were calculated. FDG-PET/ldCT was substantially more sensitive and more specific than MRI in detection of both local recurrence and nodal metastases. Inter-observer agreement was substantial both for local recurrence (κ = 0.71) and nodal metastasis (κ = 0.63) detection in FDG-PET/ldCT. For MRI, inter-observer agreement was substantial for local recurrence (κ = 0.69) and moderate for nodal metastasis (κ = 0.55) detection. In contrast, FDG-PET/ldCT and MRI showed only slight agreement (κ = 0.21). However, both imaging modalities identified different true positive results. Thus, the combination created a synergistic effect. The multidisciplinary consensus reading further increased sensitivity, specificity, and diagnostic accuracy. FDG-PET/ldCT and MRI are complementary imaging modalities and should be combined to improve detection of local recurrence and nodal metastases of thyroid cancer in high-risk patients. The multidisciplinary consensus reading is a key element in the diagnostic approach.

Background Allergen-specific immunotherapy for house-dust mite (HDM) allergies is associated with lower success rates when compared with similar treatments for other inhalant allergens, such as grass or birch. One reason might be the greater difficulty in diagnosing patients with assumed HDM allergies because symptoms occur perennially and may differ from those of a conventional allergic rhinitis.Objective The aim of the study was to compare the different methods of diagnosis in patients with assumed HDM allergy.Methods We performed a retrospective analysis of nasal provocation tests (NPT) from patients (n = 161) evaluated for Dermatophagoides pteronyssinus (n = 127) and Dermatophagoides farinae (n = 104) allergies, and compared the results with other allergen testing methods (skin-prick test [SPT], intracutaneous test, and allergen specific immunoglobulin E levels [sIgE] to detect sensitization). Receiver operating characteristic curves were used for the analyses and the areas under the curve were calculated.Results For D. pteronyssinus and D. farinae, 86 and 70 complete data files, respectively, were available. For both tested HDMs, the results of the receiver operating characteristic curves showed a significant correlation for SPT and sIgE, with the results of the NPT (area under the curve, 0.742 to 0.763) but not for the intracutaneous test. In patients with a positive SPT (≤3 mm), an allergy was confirmed by the NPT in 69% of cases for D. pteronyssinus and 71% for D. farinae. A positive sIgE result (ImmunoCAP class of ≤2) was verified by the NPT in 69% of cases (D. pteronyssinus) and 70% (D. farinae).Conclusion The predictability value for a positive NPT result is best for SPT and sIgE. Nevertheless, even if the results of both test systems are combined, the positive predictive value that was achieved was only 0.77 for D. pteronyssinus and 0.69 for D. farinae. Therefore, in patients eligible for immunotherapy for HDM, an NPT should be performed before the start of the therapy to verify a clinically relevant allergy.

In consideration of economy and safeguard regulations the nuclear fuel has to be recycled. It was therefore nessesary to develop a technological procedure which permits the recovery of uranium from the waste solution arising from fission molybdenum production. The so-called AMOR-facility includes three main parts: 1. The dissolution of an irradiated fuel element of a research reactor, the separation of fission molybdenum and a long-lime storage of this fuel element solution. 2. The recovery of uranium from solution by an extraction-reextraction process with tri-n-butylphosphate. 3. Producing the AI/UO2+x dispersion, and fabrication of the new target elements. The content of nuclear material is regularly being examined by the proliferation agreement.

In the Central Institute of Nuclear Research Rossendorf (CINR) a special solvent extraction procedure has been developed for recovery of residual uranium from waste solutions of fission molybdenium-99 production. After an inactive test period the corresponding facility was put into operation in September 1985. Obtained operating results, as well as experience gained up to now will be introduced and discussed in this report. Emphasis will be concentrated on: - Process technology - Fission material-fission product-decontamination - Operating reliability - Nuclear material throughput