Scintigraphic pattern of planar gallium scan in wound infection after colorectal surgery.

BACKGROUND

The incidence of postoperative wound infection is higher after colorectal surgery than after other surgical procedures. No studies have evaluated the usefulness of gallium 67 scintigraphy for detecting wound infection after colorectal surgery. We investigated the clinical potential of gallium imaging for detecting wound infection after colorectal surgery.

METHODS

Fifty patients who had fever after colorectal surgery were enrolled in this study. All patients had open surgical incisions at the midline of the abdomen. Planar gallium scintigraphy was performed 24 h, and then as needed, after the injection of 111 MBq (3 mCi) Ga 67 citrate. All scans were interpreted by two physicians specializing in nuclear medicine. Intensities of gallium uptake at the surgical wound were recorded as grades 0 (no uptake), 1 (less than liver uptake), 2 (equal to liver uptake), or 3 (greater than liver uptake). When the intensity of gallium uptake was equal to or greater than grade 2, gallium uptake was classified as two patterns: regular and irregular.

RESULTS

Eighteen patients were diagnosed with wound infection. When interpretation was based on only gallium-uptake intensity, the diagnostic sensitivity, specificity, and accuracy of the gallium scan were 100%, 75%, and 84%, respectively. When interpretation was based on gallium-uptake intensity and pattern, the diagnostic sensitivity and specificity were 94.4% and 96.9%, respectively. The diagnostic accuracy had increased, from 84% to 96%.

CONCLUSION

Planar gallium scan is useful for detecting wound infection after colorectal surgery. Gallium-uptake pattern and intensity are important for interpreting planar gallium scans.