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C Lueders

Publications and source records attributed to C Lueders.

3 recordsLinked to original sources

Tissue engineering of vascular conduits: fabrication of custom-made scaffolds using rapid prototyping techniques.

BACKGROUND: The technique of stereolithography, which automatically fabricates models from X-ray computed tomography or magnetic resonance imaging (MRI) data linked to computer-aided design programs, has been applied to the fabrication of scaffolds for tissue engineering. We previously reported on the application of stereolithography in scaffold fabrication of a trileaflet heart valve. In our current experiment we demonstrate a new technique for the fabrication of custom-made conduits for the potential replacement of a coarcted aortic segment. METHODS AND RESULTS: In this experiment the image data derived from a 12-year-old male patient with aortic coarctation scanned by MRI were processed by a computer-aided design program to reconstruct the aortic arch with isthmus stenosis three dimensionally. By defining the stenotic section and the adjacent normal vessel a custom-made nonstenotic descending aorta was reconstructed to replace the stenosed part. The rapid prototyping technique was used to establish stereolithographic models for fabricating biocompatible and biodegradable vascular scaffolds with the anatomic structure of the recalculated human descending aorta through a thermal processing technique. CONCLUSION: Our results suggest that the re-creation and reproduction of complex vascular structures by computer-aided design techniques may be useful to fabricate custom-made polymeric scaffolds for the tissue engineering of living vascular prostheses.

Aortic Coarctation↗

Measurement of pharmacokinetics of yttrium-86 radiopharmaceuticals with PET and radiation dose calculation of analogous yttrium-90 radiotherapeutics.

This study was performed to demonstrate the quantitative in vivo assessment of human pharmacokinetics of 90Y-radiotherapeutics using the positron-emitting substitute 86Y and PET. This technique is illustrated in a patient with disseminated bone metastases from breast cancer who was injected with 100 MBq of 86Y-citrate as an analog of the commercially available radiotherapeutic 90Y-citrate. Whole-body distribution was measured with a PET camera 4, 10, 21, 28 and 45 hr postinjection. Uptake data were determined from reconstructed transverse PET images by regions of interest placed in normal bone tissue, liver and metastases. Images of coronal and sagittal whole-body sections were obtained by reformatting the transverse PET images. The ratio of activity concentration in metastases to that in normal bone ranged from 1.5:1 to 3.5:1. Of the injected tracer, 13.4% was found in the skeleton and 0.43% in the metastasis with the highest 86Y concentration. Radiation doses per 1 MBq of injected 90Y-citrate were calculated from 86Y-citrate data and data from MIRD pamphlets 5 and 11. The doses were 1.01 MGy/MBq for red marrow, 593 microGy/MBq for the liver and approximately 3.5 MGy/MBq for the most conspicuous metastases. This study demonstrates that the use of PET via 86Y allows an individual in vivo quantification of activity uptake and radiation dose of both normal tissue and tumor in pain treatment with 90Y-labeled radiotherapeutics.

Adult↗

[Radiosynoviorthesis].

Intraarticular therapy using radionuclides seems to be the best conservative local treatment of chronic synovitis as a generally accepted alternative to surgical synovectomy. If the indication is carefully considered and the technique properly applied, the success rate of treatment is as high as it is with surgery, whereas the risk involved is comparatively low.

Arthritis, Rheumatoid↗