Posttherapy technetium-99m pentavalent dimercaptosuccinic acid brain single-photon emission computed tomography/computed tomography: diagnostic and prognostic values in patients with glioma.

PURPOSE: To assess the value of posttherapy 99mTc-pentavalent dimercaptosuccinic acid (DMSA-V) brain SPECT/CT in patients with brain glioma. METHODS: Patients with pathologically or radiologically proven glioma were prospectively enrolled in this study. 99mTc-DMSA-V brain SPECT/CT images were acquired at 120-180 min after i.v. injection of 555-740 MBq of 99mTc-DMSA-V. Three nuclear medicine physicians blindly interpreted the scans visually as positive or negative for residual/recurrent disease. Agreement between two or more readers was considered a consensus. The composite reference standard was considered based on subsequent clinical/neuroimaging follow-up or histopathology whenever available. Overall survival (OS) was calculated from the date of initial diagnosis till the death or the date of last follow-up. RESULTS: Thirty-four patients (18 males and 16 females; mean age 37.7 ± 16 years) were enrolled in this study. Interreader agreement between the readers ranged from 0.71 to 0.82. Based on the composite reference standard, residual/recurrent disease was confirmed in 16 patients, whereas 18 patients were negative for disease. Consensus reading of 99mTc-DMSA-V SPECT/CT accurately diagnosed 13 true positive (sensitivity 81%) and 17 true negative scans (specificity 94%). After a median follow-up of 22.9 months, 7/14 patients with positive 99mTc-DMSA-V SPECT/CT brain readings died compared to 4/20 with negative readings. The median survival was 24.1 months for the positive group and was not reached for the negative group. CONCLUSION: Posttherapy brain SPECT/CT scanning with 99mTc-DMSA-V is a noninvasive, reliable, and specific tool for evaluation of patients with brain glioma after definitive therapy. Scan positivity was associated with poor OS.

Hybrid SPECT/CT Helps Characterization and Localization of a Dual Thyroid Ectopia.

The presence of ectopic thyroid tissue in 2 or more different sites is rare. A 12-year-old girl presented with midline anterior neck swelling in the infrahyoid region with subclinical hypothyroidism. Thyroid scanning with Tc-pertechnetate was performed, and SPECT/CT was ordered for further evaluation. Two hyperdense lesions demonstrating intense radiotracer uptake were seen in the midline at the base of the tongue and infrahyoid neck. We emphasis the role of hybrid SPECT/CT for characterization and localization of suspected ectopic thyroid tissue.