Brain scanning in the diagnosis of acoustic neuromas

Abstract

✓ Of 22 patients found to have acoustic neuromas at surgery, 99m Tc-sodium pertechnetate brain scans correctly identified these tumors in 18. This successful imaging is due largely to two factors: the improved visualization of the posterior cranial fossa with technetium 99m and the use of delayed scans. With the latter, it was found that the optimum time for scanning acoustic neuromas was 2½ hours following radionuclide administration; scans performed before that time failed to visualize the tumor in five patients whose studies were positive on delayed scans. The authors feel that for acoustic neuromas 2 cm or more in diameter, 99m Tc scanning is the diagnostic procedure of choice and is especially useful in detecting tumor recurrence.