SPECT/CT in the Evaluation of Frostbite

Frostbite remains a challenging clinical scenario with multiple treatment algorithms and variable results. Currently, frostbite management often follows a conservative approach with rewarming followed by wound care and delayed amputation. We review seven patients where single-photon emission computed tomography (SPECT) fused with conventional computed tomography was used to evaluate tissue viability for earlier directed debridement and limb salvage. The goal of this report is to evaluate SPECT/CT as an appropriate modality for the screening of necrotic bone for earlier amputation in patients with frostbite. We retrospectively analyzed the records of seven patients (19 extremities) with frostbite who received SPECT/CT scans to evaluate deep tissue necrosis before digit amputation. All patients who presented within the first 24 hr following their injury without contraindications were initially treated with tissue plasminogen activator. Three patients met criteria and were treated with tissue plasminogen activator. Of the seven patients analyzed, none required revision amputation beyond the level predicted on SPECT/CT scan. No patients had viable tissue distal to the most distal extent of bone perfusion. In six of the patients, the SPECT/CT scan led to more distal amputation with proximal debridement of soft tissues thus maintaining extremity length. Frostbite remains a challenging clinical scenario for which there are a wide number of clinical algorithms. SPECT/CT appears to be valuable in the evaluation of frostbite to determine the need for amputation. Fusion of the nuclear images with the CT allows for more exact delineation of the level of amputation than a bone scan alone.