RSNA 2003 

Abstract Archives of the RSNA, 2003


218-p

Dynamic Data Acquisition of the Double Phase Parathyroid Imaging with Tc-99m Sestamibi (MIBI): Does It Provide Additional Information?

Scientific Posters

Presented on December 1, 2003
Presented as part of D23: Nuclear Medicine Endocrine

Participants

Hassan Semaan MD, PRESENTER: Nothing to Disclose

Abstract: HTML Purpose: Dual radionuclide imaging using a combination of Tl-201 with either Tc-99m pertechnetate or I-123 is a recognized protocol for the localization of parathyroid adenomas. Tc-99m MIBI has also been used as an alternative protocol, taking advantage of the differential rates of washout. The purpose of this study was to determine if a dynamic acquisiton with MIBI of the initial "thyroid" phase, would be able to predict the outcome of the delayed "parathyroid" phase. Methods and Materials: Data collected over the last 8 years was analyzed. 97 patients suspected of hyperparathyroidism were injected with 740 MBq (20 mCi) of MIBI. 26 patients were imaged strictly with the dual phase technique and were excluded from the protocol. The remaining 71 patients were imaged in dynamic fashion at a rate of 5 sec/frm for 20 min in a 128 x 128 matrix, using a pinhole collimator. A composite image was made of the last 5 minutes of data of this initial phase. The delayed phase static image was acquired 3 hours later, using the same matrix size, collimator setup and distance. Identical ROI's were drawn around each thyroid lobe. Time activity curves (TAC's) and differential uptake (%) were determined for both thyroid lobe regions. The dynamic data results were then compared to the delayed phase. Results: 46 patients had an abnormal scan with a solitary located adenoma. A higher TAC and increased % demonstrated the affected lobe. This agreed with the findings of the dual phase technique. Only in a single case, the TAC and % disagreed as to the location of the adenoma. 10 patients had bilaterally located adenomas. The TAC and % agreed with the site containing the higher intensity adenoma. 15 patients were determined to be negative. 3 of them had subsequent surgical findings. In two of these patients the TAC and % correctly identified the site of the adenoma determined at surgery. Conclusion: Dynamic acquisition provides further support for the diagnosis of parathyroid adenoma in a positive study. This may offer the physician an added feeling of confidence, especially in those borderline cases. Furthermore, it may also suggest additional work up. For those studies determined to be negative, that still proceed with surgery, it may help by suggesting which side to perform the exploratory intervention first.      

Cite This Abstract

Semaan MD, H, Dynamic Data Acquisition of the Double Phase Parathyroid Imaging with Tc-99m Sestamibi (MIBI): Does It Provide Additional Information?.  Radiological Society of North America 2003 Scientific Assembly and Annual Meeting, November 30 - December 5, 2003 ,Chicago IL. http://archive.rsna.org/2003/3105358.html