Is there a role of near-infrared spectroscopy in predicting the outcome of patients with carotid artery occlusion?
BACKGROUND
Transcranial Doppler (TCD) studies demonstrated that cerebral vasomotor reactivity (VMR) can predict the outcome of carotid artery occlusion (CAO). Near-infrared spectroscopy (NIRS) is a non-invasive optical method for assessing hemoglobin (Hb) oxygenation parameters. The purpose of this study was to evaluate the role of NIRS parameters as prognostic markers of stroke occurrence in patients with CAO.


METHODS
Sixty-five patients (46 men, mean age 68.8 years) with CAO were enrolled. Forty-two patients had previous cerebrovascular events (15 TIA, 27 minor stroke), the remaining 23 were asymptomatic. All subjects underwent simultaneous TCD and NIRS examination at rest and after hypercapnia. All patients completed follow-up (median, 36 months).


RESULTS
During follow-up, 11 strokes occurred. Cerebral VMR measured by TCD had a prognostic role in stroke occurrence (p=0.042). The increase in Hb oxygen saturation detected by NIRS during hypercapnia predicted the occurrence of new cerebrovascular events, although without an overt significance (p=0.058). Hb oxygen saturation at rest, however, failed to be of prognostic value (p=0.65).


CONCLUSIONS
NIRS is potentially useful in monitoring cerebral oxygenation; however, at present NIRS does not effectively predict the outcomes of stroke or vascular death in patients with CAO. This study does confirm the primary role of TCD VMR in the outcome of carotid disease.
Palazzo
Paola
P
Neurologia Clinica, Università Campus Bio-Medico, Roma, Italy.
Tibuzzi
Francesco
F
Pasqualetti
Patrizio
P
Altamura
Claudia
C
Silvestrini
Mauro
M
Passarelli
Francesco
F
Rossini
Paolo M
PM
Vernieri
Fabrizio
F
D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity; D002339:Carotid Arteries / Q000000981:diagnostic imaging*; D016893:Carotid Stenosis / Q000150:complications / Q000000981:diagnostic imaging*; D002560:Cerebrovascular Circulation / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D011379:Prognosis; D012044:Regression Analysis; D019265:Spectroscopy, Near-Infrared; D020521:Stroke / Q000000981:diagnostic imaging* / Q000209:etiology; D014463:Ultrasonography