Utility of ⁹⁹mTc-human serum albumin diethylenetriamine pentaacetic acid SPECT for evaluating endoleak after endovascular abdominal aortic aneurysm repair.

Abstract

OBJECTIVE:

The purpose of this study was to assess the utility of (99m)Tc-human serum albumin diethylenetriamine pentaacetic acid ((99m)Tc-HSAD) SPECT in the detection of endoleaks after endovascular abdominal aortic aneurysm repair.

SUBJECTS AND METHODS:

Fifteen patients (11 men, four women) with aneurysm sac expansion of 5 mm or greater after endovascular abdominal aortic aneurysm repair underwent three-phase CT, (99m)Tc-HSAD SPECT, and CT during aortography. Sensitivity calculations for three-phase CT and (99m)Tc-HSAD SPECT were performed with CT during aortography as the reference standard. The volume of each endoleak was measured with CT during aortography. Seven subjects underwent embolization with N-butyl cyanoacrylate (NBCA)-Lipiodol (ethiodized oil, Guerbet and metallic coils. Three-phase CT and (99m)Tc-HSAD SPECT were repeated after embolization to assess their efficacy.

RESULTS:

Endoleaks were interpreted as perigraft radioisotope accumulation in 12 patients (80.0%) on (99m)Tc-HSAD SPECT images, in 13 patients (86.7%) on three-phase CT images, and in 15 patients (100%) on CT during aortography. The mean endoleak volume visualized with (99m)Tc-HSAD SPECT was 8.37 cm(3) (range, 5.2-15.1 cm(3)), and the volume not visualized was 3.47 cm(3) (2.5-4.6 cm(3)), a statistically significant difference (p = 0.019). In two patients, (99m)Tc-HSAD SPECT depicted endoleaks evident at delayed phase CT during aortography but not at three-phase CT, suggesting they were slow-filling endoleaks. Accumulation of (99m)Tc-HSAD corresponding to endoleaks disappeared after embolization, but CT evaluation of embolization was impeded by artifacts of NBCA-Lipiodol and metallic coils.

CONCLUSION:

Technetium-99m-labeled HSAD SPECT proved less sensitive than three-phase CT but depicted endoleaks with volumes 5.2 cm(3) or greater as perigraft radioisotope accumulation. Slow-filling endoleaks can be visualized with (99m)Tc-HSAD SPECT, which can be used to evaluate the efficacy of embolization.

• Authors: Motoki Nakai, Hirotatsu Sato, Morio Sato, Akira Ikoma, Tetsuo Sonomura, Yoshiharu Nishimura, Yoshitaka Okamura
• Journal: AJR. American journal of roentgenology (AJR Am J Roentgenol) Vol. 204 Issue 1 Pg. 189-96 (Jan 2015) ISSN: 1546-3141 [Electronic] United States
• PMID: 25539256 (Publication Type: Clinical Trial, Journal Article)

Chemical References

• Radiopharmaceuticals
• Technetium Tc 99m Aggregated Albumin
• technetium Tc 99m DTPA HSA
• Technetium Tc 99m Pentetate

Topics

• Aged
• Aged, 80 and over
• Aortic Aneurysm, Abdominal (complications, diagnostic imaging, surgery)
• Endoleak (diagnostic imaging, etiology)
• Endovascular Procedures (adverse effects, instrumentation)
• Female
• Humans
• Male
• Middle Aged
• Radiopharmaceuticals
• Reproducibility of Results
• Sensitivity and Specificity
• Stents (adverse effects)
• Technetium Tc 99m Aggregated Albumin
• Technetium Tc 99m Pentetate
• Tomography, Emission-Computed, Single-Photon (methods)
• Treatment Outcome