title: Detection of endoleaks after endovascular aneurysm repair with use of technetium-99m sulfur colloid and (99m)Tc-labeled red blood cell scans.
abstract: OBJECTIVE
  This study was performed to determine whether endoleaks could be detected after endovascular aneurysm repair (EVAR) with use of technetium-99m sulfur colloid and (99m)Tc-labeled red blood cell (RBC) nuclear medicine scans.
  
  
  METHODS
  There were 13 patients enrolled in this study: nine with endoleaks seen on computed tomographic (CT) angiography and four with no endoleak on CT angiography. All patients underwent regularly scheduled surveillance CT angiography examination after EVAR to evaluate for endoleak. Endoleak detection was then attempted in each patient with two nuclear medicine scans: a (99m)Tc sulfur colloid scan and a (99m)Tc-labeled RBC scan. Flow images (5 seconds per frame) were obtained for 1 minute after intravenous administration of 555 MBq (15 mCi) (99m)Tc sulfur colloid. Sequential dynamic images were then obtained every minute for 30 minutes. Next, a (99m)Tc-labeled RBC study was performed after the intravenous administration of 370-1,073 MBq (10-29 mCi) in vitro labeled (99m)Tc RBCs. Flow images were obtained, followed by sequential dynamic images obtained every minute for 30 minutes. Single photon emission CT images of the abdomen were then acquired. The nuclear medicine scans were evaluated for the presence or absence of endoleak independent of the CT angiography findings.
  
  
  RESULTS
  Of the nine patients with endoleaks on CT angiography, seven (78%) had them detected by nuclear medicine examinations. Two of the nine endoleaks seen on CT angiography (22%) were not seen on either scintigraphic examination. All patients with no endoleak on CT angiography had their nuclear medicine scans correctly interpreted as showing no endoleak present (n = 4; 100%). No complications occurred as a result of the nuclear medicine scans.
  
  
  CONCLUSIONS
  Endoleaks can be detected with (99m)Tc sulfur colloid and (99m)Tc-labeled RBC nuclear medicine scans. This initial work suggests that the sensitivities of these scintigraphic scanning methods for endoleak detection are lower than that of CT angiography.
authors.affiliation: Department of Radiology, Hospital of the University of Pennsylvania, 1 Silverstein, 3400 Spruce Street, Philadelphia, Pennsylvania 19104, USA. stav@uphs.upenn.edu
authors.forename: S William
authors.initials: SW
authors.lastname: Stavropoulos
authors.forename: Maxim
authors.initials: M
authors.lastname: Itkin
authors.forename: Paras
authors.initials: P
authors.lastname: Lakhani
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Carpenter
authors.forename: Ronald M
authors.initials: RM
authors.lastname: Fairman
authors.forename: Abass
authors.initials: A
authors.lastname: Alavi
mesh_terms: D017544:Aortic Aneurysm, Abdominal / Q000601:surgery*; D004912:Erythrocytes; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008657:Metabolic Clearance Rate; D011183:Postoperative Complications / Q000000981:diagnostic imaging*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012086:Reoperation; D015607:Stents; D013514:Surgical Procedures, Operative; D013667:Technetium; D013671:Technetium Tc 99m Sulfur Colloid; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D013671:Technetium Tc 99m Sulfur Colloid; D013667:Technetium