sodium-pertechnetate-tc-99m and Frostbite

No large prospective study is available on use of a radionuclide method to assess frostbite and its response to conservative treatment. Recently, a large retrospective study using two-phase bone scintigraphy suggested that non-uptake (or low uptake) in frostbite lesions in the blood pool or bone phase had a strong correlation with the subsequent need for amputation. In the present study, we performed early blood pool scintigraphy with technetium-99m pertechnetate in 20 patients (10-180 days after frostbite injury; 71 clinical lesions) referred for a topical treatment protocol for mild to moderately severe frostbite, and in 22 asymptomatic controls. The aims of the study were to define the "normal" microcirculation of the hands and feet, to characterise the appearances of frostbite lesions on scintigraphy and correlate these with the clinical presentation, and to evaluate the usefulness of scintigraphy for assessing the treatment response. Six patients were "fresh", 12 had been undergoing conservative treatment (topical homeopathic) for several weeks and two had permanent fibrotic hand phalanges. Nine patients on treatment underwent serial scintigraphy a total of 22 times. Eleven patients were imaged only once, including the two with permanent fixed defects. Three distinct physiological microcirculation patterns were evident in control hands or feet: right- or left-handedness (seven subjects), subclinical inflammatory foci correlating with callosity or pressure points (36 lesions) and distinctly increased pooling of radiotracer at the thenar or hypothenar region (eight subjects). In frostbite patients, 128 lesions (48 inflammatory, 80 ischaemic) were seen on the scan. This number included all 71 lesions identified clinically, the rest being subclinical. Subclinical frostbite lesion as an entity has not been described previously. Microvasculature of normal muscle groups (in the hands, elbow or feet) was shown on scintigraphy to improve after topical treatment. The treatment resulted in improved or normalised perfusion scan in 25 of 45 ischaemic segments with matching clinical improvement, and reduction or normalisation of uptake in inflammatory lesions (n=30). The data confirm the vasodilator and anti-inflammatory action of the topical preparation, and the sensitivity of the radionuclide method in monitoring treatment response. In contrast to the previous findings that non-uptake on a scan performed 2 or more weeks after exposure correlates with the need fo

Topics: Adolescent; Adult; Case-Control Studies; Child; Female; Fibrosis; Foot; Foot Injuries; Frostbite; Hand; Hand Injuries; Homeopathy; Humans; Male; Microcirculation; Middle Aged; Prospective Studies; Radionuclide Imaging; Radiopharmaceuticals; Sodium Pertechnetate Tc 99m

Topics: Frostbite; Hand; Humans; Radionuclide Imaging; Regional Blood Flow; Sodium Pertechnetate Tc 99m

Technetium-99m pertechnetate scintigraphy was performed in the involved extremities of six patients with severe frostbite of the hands (six cases) and feet (one case). There was good correlation between the scintigraphic findings and the extent of deep tissue ultimately requiring surgical resection. Technetium-99m pertechnetate imaging distinguishes viable from dead tissue in frostbite in a simple, noninvasive manner, and findings are easy to interpret. A persistent perfusion defect is seen in nonviable tissue.

Topics: Adolescent; Adult; Foot Injuries; Frostbite; Hand Injuries; Humans; Male; Middle Aged; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Technetium