Imaging of frostbite injury by technetium-99m-sestamibi scintigraphy: a case report

The appearance of superficial tissue is often an unreliable indicator of deep-tissue viability in cases of frostbite. We present a 34-year-old black man who was brought to the emergency department at fourth post-injury day with frostbite injury involving both lower extremities after prolonged exposure to subzero temperatures. In our previous experimental study, 99mTc sestamibi scintigraphy has been employed for evaluating frostbite injuries in rabbit hindlegs. In the case presented, 99mTc sestamibi scintigraphy, as a new diagnostic tool, was performed for detection of skeletal muscle perfusion on the fourth post-injury day. The scintigraphic images show diffusely reduced uptake in soft tissues of both calves and feet. It was thought that this hypoperfusion was due to viable but ischemic tissue. Five days after medical therapy, 99mTc sestamibi scan showed prominently increased uptake in both calves and feet and skin necrosis was observed. Debridement of necrotic skin and subcutaneous tissue was performed, and split-thickness skin graft was applied for coverage of the skin defect. Healing was good 15 days after grafting. We think 99mTc sestamibi scan can be used for assessment of soft-tissue perfusion and evaluation of treatment in frostbite injury.