Maybe we don't need delayed parathyroid imaging

Sarv Priya; Michael Graham

Objectives: Parathyroid adenoma scintigraphy has evolved from combined Tl-201 and Tc99m pertechnetate imaging to early and late Tc99m sestamibi imaging to current practice of combined early/late sestamibi with pertechnetate and SPECT-CT. We hypothesized that, since now we have sestamibi and pertechnetate along with SPECT -CT, it may no longer be necessary to perform delayed sestamibi imaging. Methods: Retrospectively, we identified 43 consecutive patients who had combined early/late sestamibi with pertechnetate and SPECT-CT studies for possible parathyroid adenoma. The studies were performed at our institution during 2013. An image review workflow was set up that only displayed the early sestamibi (at 15 minutes after injection) and pertechnetate planar and SPECT images. One reader scored all the studies on a scale of 1 to 5 as definitely normal , probably normal, equivocal, probably abnormal, and definitely abnormal. Regions scored were upper and lower, left and right. All studies were read a second time with another image review workflow that also showed the planar and SPECT images for delayed sestamibi at 90 minutes after injection. Results: Five patients were not evaluable because of missing images. In the 38 remaining patients, four sites were evaluated for each patient, for a total of 152 sites. Among those sites there was score disagreement of 1 or greater between the reads with and without the delayed images in 56 instances (36%). Similarly, there was disagreement by scores of 2 or more in 35 instances (23%). Conclusions: The disagreement of scores by 2 or more would result in a change in interpretation from positive to negative. If this were to happen 23% of the time, it would be unacceptable. Although the number of subjects is low, the results are strongly suggestive that delayed imaging provides a significant contribution to the interpretation of parathyroid adenoma scintigraphy.

Maybe we don't need delayed parathyroid imaging

View Online

Abstract

Details

Metrics