Luminescence ratiometric oxygen imaging (LROI) in microvascular anastomosed fibular and radial forearm flaps
Issue title: Selected articles of the 14th International Congress of Biorheology and the 7th International Conference of Clinical Hemorheology, July 4–7, 2012, Istanbul, Turkey
Affiliations: Department of Cranio-Maxillo-Facial Surgery, University Medical Centre Regensburg, Regensburg, Germany | Department of Trauma and Plastic Surgery, University Medical Centre Regensburg, Regensburg, Germany | PreSens GmbH, Regensburg, Germany
Note: [] Corresponding author: Martin Gosau, PhD, MD, DMD, Department of Cranio-Maxillo-Facial Surgery, 93042 Regensburg, Germany. Tel.: +49 941 944 6345; Fax: +49 941 944 6342; E-mail: [email protected]
Abstract: BACKGROUND: In a preliminary trial, we were able to show first promising results in the analysis of perioperative and postoperative perfusion of free flaps by means of a new monitoring system for detecting thrombotic vessel occlusion before clinical signs become evident. OBJECTIVE: We investigated whether flap monitoring by measuring perfusion-dependent parameters differs between radial forearm and fibular free flaps and whether a threshold value requiring anastomosis revision could be determined. METHODS: 37 radial forearm flaps (RF) and 15 fibular flaps (FF) were harvested and transplanted. Perfusion was determined by measuring a fluorescent oxygen sensor foil covering a flap's skin surface with a handheld fluorescence microscope. The sensor contained an oxygen reservoir, which was consumed by the tissue corresponding to the perfusion status of the flap. Measurements were done before explantation, after successful anastomosis and one day after surgery. RESULTS: We found a significant difference (p < 0.005) in the relative transdermal oxygen consumption (RTOC) between clinically well-perfused grafts (RF: mean: 0.13 ± 0.08; FF: mean: 0.15 ± 0.07) and clinically poorly perfused grafts (RF: mean: 0.40 ± 0.09; FF: mean: 0.55 ± 0.28). A threshold RTOC value of 0.3 for differentiating between well-perfused and poorly perfused flaps was confirmed for both RF and FF.
