title: Usefulness of 99mTc-ECD brain SPECT with voxel-based analysis in evaluation of perfusion changes early after carotid endarterectomy.
abstract: BACKGROUND
  Association between preoperative perfusion pattern and reperfusion after carotid endarterectomy (CEA) is an important yet unexplored topic. Therefore, the aim of our study was to determine whether 99mTc-ECD single-photon emission computed tomography (SPECT) performed before carotid endarterectomy in patients with internal carotid artery (ICA) stenosis may be helpful in predicting early perfusion changes after revascularization.
  
  
  METHODS
  The examined group consisted of 30 patients (mean age 67.4±9.6 years) with ICA stenosis who underwent CEA. Infarction was demonstrated on computed tomography (CT) in 12 cases. Brain perfusion SPECT was performed 1-3 days before CEA and 3-5 days after the surgery. Voxel-based analysis was carried out with Brain SPECT Quantification software. For evaluation of preoperative interhemispheric asymmetry of perfusion, the percentage asymmetry index (AI) was calculated. For comparison of perfusion before and after CEA, the percentage relative difference (RD) was computed.
  
  
  RESULTS
  Before CEA, cerebral hypoperfusion was seen in 26 cases, including 15 participants with normal CT. After CEA, the following changes of perfusion were observed: perfusion increase n=18 (ipsilateral and bilateral), deterioration n=1, mixed patterns n=2, no change n=9. In patients with preoperative ipsilateral hypoperfusion and perfusion increase after CEA, AI correlated significantly with RD (r=0.48, p=0.04).
  
  
  CONCLUSIONS
  Our results suggest that perfusion increase 3-5 days after CEA is higher in patients with greater ipsilateral asymmetry index. Evaluation of preoperative AI may help to identify patients in whom rapid reperfusion is more likely.
authors.affiliation: Department of Nuclear Medicine, Medical University of Lublin, Lublin, Poland. ampolak@o2
authors.forename: Anna
authors.initials: A
authors.lastname: Nocuń
authors.forename: Marek
authors.initials: M
authors.lastname: Wilczyński
authors.forename: Jacek
authors.initials: J
authors.lastname: Wroński
authors.forename: Beata
authors.initials: B
authors.lastname: Chrapko
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000000981:diagnostic imaging* / Q000601:surgery*; D003545:Cysteine / Q000031:analogs & derivatives*; D016894:Endarterectomy, Carotid / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds; D010477:Perfusion; D011300:Preoperative Care; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D015609:Organotechnetium Compounds; C059659:technetium Tc 99m bicisate; D003545:Cysteine