title: The neurological morbidity of carotid revascularisation: using markers of cellular brain injury to compare CEA and CAS.
abstract: OBJECTIVE
  This comparative study attempts to evaluate the profile of S-100beta and Neuron-Specific Enolase (NSE), biomarkers of brain injury, in patients undergoing carotid endarterectomy (CEA) and carotid artery stenting (CAS) and to correlate this with haemodynamic and embolic events detected using trans-cranial Doppler (TCD).
  
  
  METHODS
  52 patients with internal carotid artery stenosis requiring intervention were recruited. 24 patients underwent CAS, and 28 underwent CEA. TCD was performed peri-operatively to record mean Middle Cerebral Artery (MCA) velocity and number of High Intensity Transient Signals (HITS) in the MCA of the operated side. Serum was drawn pre-operatively and at six time points in a 48 hour post-operative period, and then assayed using automated commercial equipment. Within and between group variability in markers were assessed by Generalized Estimation Equations modelling.
  
  
  RESULTS
  CAS caused more HITS (p=0.028) but less haemodynamic disturbance (p=0.0001) than CEA. Treatment modality (CAS versus CEA) had no direct effect on S-100 changes (p=0.467). NSE levels declined after revascularisation in the CAS group but not after CEA (p=0.002). S-100beta levels rose in patients who had higher numbers of HITS (p=0.002). S-100beta and NSE were not associated with changes in MCA velocity (p>0.5). S-100beta alone increased significantly at 24 hours in those patients with a post-operative neurological deficit (p=0.015).
  
  
  CONCLUSIONS
  Trans-cranial Doppler findings suggest that the mechanisms of rise in S-100beta and NSE levels may differ and may be due to increased peri-operative micro-embolisation and cerebral hypoperfusion respectively. Further studies are required to assess the clinical significance of these observed changes.
authors.affiliation: Imperial College London, St Mary's Hospital, Paddington, London, UK.
authors.forename: R E
authors.initials: RE
authors.lastname: Brightwell
authors.forename: R A
authors.initials: RA
authors.lastname: Sherwood
authors.forename: T
authors.initials: T
authors.lastname: Athanasiou
authors.forename: M
authors.initials: M
authors.lastname: Hamady
authors.forename: N J W
authors.initials: NJ
authors.lastname: Cheshire
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000800:Angioplasty, Balloon / Q000009:adverse effects*; D001783:Blood Flow Velocity; D002545:Brain Ischemia / Q000175:diagnosis / Q000209:etiology*; D002343:Carotid Artery, Internal; D016893:Carotid Stenosis / Q000000981:diagnostic imaging / Q000601:surgery / Q000628:therapy*; D016894:Endarterectomy, Carotid / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D009414:Nerve Growth Factors / Q000097:blood*; D010751:Phosphopyruvate Hydratase / Q000097:blood*; D011184:Postoperative Period; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000097:blood*; D015607:Stents; D017585:Ultrasonography, Doppler, Transcranial
chemical_list: D009414:Nerve Growth Factors; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; D010751:Phosphopyruvate Hydratase