title: Magnetic resonance angiography, digital subtraction angiography and Doppler ultrasonography in detection of carotid artery stenosis: a comparison with findings from histological specimens.
abstract: BACKGROUND
  Patients' life expectancy, clinical symptomatology and the extent of carotid stenosis are the most important factors when deciding whether to perform carotid endarterectomy (CEA) in patients with carotid stenosis. Therefore, the accuracy of measuring carotid stenosis is of utmost importance.
  
  
  METHODS
  Patients with internal carotid artery (ICA) stenosis were investigated by digital subtraction angiography (DSA), Doppler ultrasonography (DUS) and magnetic resonance angiography (MRA). Atherosclerotic plaque specimens were transversally cut into smaller segments and histologically processed. The slides were scanned and specimens showing maximal stenosis were determined; the minimal diameter and the diameter of the whole plaque were measured. DSA, DUS and MRA measurements were obtained in 103 patients. A comparison between preoperative and histological findings was performed. In addition, correlation coefficients were computed and tested.
  
  
  RESULTS
  Results show a significant correlation for each of the diagnostic procedures. Mean differences in the whole cohort between preoperative measurements and the histological measurements are as follows: angiographic measurement of carotid stenosis underestimated histological measurement by 14.5% and MRA by 0.7%, but DUS overestimated by 6.6%. The results in severe stenosis (> or =70%) are as follows: angiographic measurement underestimated the histological measurements by 2.3%, but MRA overestimated by 12.1% and DUS by 11.3%. The results in moderate stenosis (50-69%): angiographic measurement underestimated the histological measurements by 12.3%, but MRA overestimated by 0.2% and DUS by 7.2%. The results in mild stenosis (30-49%): angiographic measurement underestimated the histological measurements by 24.7% and MRA by 7.6%, but DUS overestimated by 3.3%.
  
  
  CONCLUSIONS
  Our study confirms that DSA underestimates moderate and mild ICA stenosis. DUS slightly overestimated moderate ICA stenosis and highly overestimated high-grade ICA stenosis. MRA proved to be accurate in detecting moderate ICA stenosis, but slightly underestimated mild stenosis and overestimated high-grade stenosis. The surgeon should be aware of these discrepancies when deciding whether to perform CEA in patients with ICA stenosis.
authors.affiliation: Department of Neurosurgery, First Faculty of Medicine, Central Military Hospital, U Vojenské Nemocnice 1200, 169 02, Prague 6, Czech Republic.
authors.forename: David
authors.initials: D
authors.lastname: Netuka
authors.forename: Svatopluk
authors.initials: S
authors.lastname: Ostrý
authors.forename: Tomás
authors.initials: T
authors.lastname: Belsán
authors.forename: David
authors.initials: D
authors.lastname: Rucka
authors.forename: Václav
authors.initials: V
authors.lastname: Mandys
authors.forename: Frantisek
authors.initials: F
authors.lastname: Charvát
authors.forename: Ondrej
authors.initials: O
authors.lastname: Bradác
authors.forename: Vladimír
authors.initials: V
authors.lastname: Benes
mesh_terms: D015901:Angiography, Digital Subtraction / Q000379:methods / Q000592:standards; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000473:pathology*; D016893:Carotid Stenosis / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology*; D015331:Cohort Studies; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods / Q000592:standards; D011237:Predictive Value of Tests; D011300:Preoperative Care / Q000379:methods; D018608:Ultrasonography, Doppler / Q000379:methods / Q000592:standards