Chronic exertional compartment syndrome in lower legs: localization and follow-up with thallium-201 SPECT imaging

The purpose of this study was to ascertain whether 201Tl SPECT imaging of the leg is useful in precise localization of the ischemic compartment involved in chronic exertional compartment syndrome (CECS).

Imaging and quantitative analyses of postexercise 201Tl SPECT leg examinations were retrospectively performed in nine patients with clinically diagnosed CECS and eight control subjects. Imaging and quantitative criteria for the ischemic compartment were decreased 201Tl perfusion less than the lower limits of normal, which were defined as 2 s.d. below the mean percentage uptake of the control subjects. The SPECT imaging results were compared with those of quantitative analysis, postoperative SPECT images and clinical diagnoses.

Postexercise normal legs had nonuniform 201Tl distribution in both legs and in the four compartments. Lower limits of normal mean percentage 201Tl uptake were about 60% for the anterior compartment and about 50% for the other three compartments. Redistribution was observed in 67% of normal compartments in the control subjects. The SPECT images demonstrated 16 ischemic compartments in eight of the nine patients. The SPECT results were consistent with those of quantitative analysis. There were discrepancies between the clinical and SPECT diagnoses in six legs (33% of the 18 legs) of five patients. Postoperative SPECT demonstrated 201Tl perfusion was improved in all involved compartments for that fasciotomy was performed.

Thallium-201 SPECT imaging of the legs can easily provide precise localization of the ischemic compartment, which is demonstrated as decreased 201Tl distribution on the stress image. This technique is promising for the screening and follow-up of CECS.