BONE-SCINTIGRAPHY IN THE EVALUATION OF BONE-GRAFTS USED FOR MANDIBULAR RECONSTRUCTION

Bone scintigraphy was applied in the followup of 24 patients who recei ved bone grafts for reconstruction of the mandible after partial resec tion. Semi-quantitative assessment of the grafts was done with a six-g rade scoring system, based on comparison of tracer uptake in the graft and in the calvarium (as an internal control). Sixty-nine bone scans were evaluated. Late planar imaging was carried out in all cases, and single-photon emission tomography (SPET) was performed additionally in 34 of these cases. Complications were observed in four grafts. They o ccurred less frequently in revascularized grafts than in non-revascula rized grafts. Planar scintigrams performed within 14 days after recons truction showed a significantly higher tracer uptake in grafts with an uncomplicated further course than in those which developed complicati ons. Follow-up scintigrams after 1 and 3 months revealed a significant increase in tracer uptake in grafts with an uncomplicated course. Thi s was not apparent in grafts which developed complications. The tracer uptake was estimated to be higher on the basis of the SPET scans as c ompared with the planar scintigrams. It is concluded that bone scintig raphy is of prognostic value in the evaluation of bone grafts used for mandibular reconstruction. SPET seems to be more sensitive than plana r imaging for the assessment of graft viability.