Ultrasonography of the optic nerve sheath may be useful for detecting raised intracranial pressure after severe brain injury.
OBJECTIVE
To assess at admission to the ICU the relationship between optic nerve sheath diameter (ONSD) and intracranial pressure (ICP) and to investigate whether increased ONSD at patient admission is associated with raised ICP in the first 48[Symbol: see text]h after trauma.


METHODS
Prospective, blind, observational study in a surgical critical care unit, level 1 trauma center.


METHODS
31 adult patients with severe traumatic brain injury (TBI; Glasgow coma scale <or=8) requiring sedation and ICP monitoring, and 31 control patients without brain injury requiring sedation.


RESULTS
ONSD was measured with a 7.5-MHz linear ultrasound probe. Two TBI groups were defined on the basis of ICP profile. If ICP exceeded 20 mmHg for more than 30 min in the first 48 h (before any specific treatment), patients were considered to have high ICP; if not, they had normal ICP. The largest ONSD value (the highest value for the right and left eye) was significantly higher in high ICP patients (6.3 +/-0.6 vs. 5.1+/-0.7 mm in normal ICP patients and 4.9+/-0.3mm in control patients). There was a significant relationship between the largest ONSD and ICP at admission (r=0.68). The largest ONSD was a suitable predictor of high ICP (area under ROC curve 0.96). When ONSD was under 5.7 mm, the sensitivity and negative predictive values for high ICP were 100%.


CONCLUSIONS
In the early posttraumatic period, ocular ultrasound scans may be useful for detecting high ICP after severe TBI.
Department of Anesthesiology and Critical Care Medicine, Hospital of Bicêtre, Assistance Publique-Hôpitaux de Paris (AP-HP), Faculty of Medicine, University of Paris-Sud, Le Kremlin Bicêtre, 94275, Paris, France. thomas.geeraerts@bct.aphp.fr
Thomas
T
Geeraerts
Yoann
Y
Launey
Laurent
L
Martin
Julien
J
Pottecher
Bernard
B
Vigué
Jacques
J
Duranteau
Dan
D
Benhamou
D000328:Adult; D001930:Brain Injuries / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D006801:Humans; D019586:Intracranial Hypertension / Q000000981:diagnostic imaging* / Q000503:physiopathology; D007427:Intracranial Pressure; D008297:Male; D009900:Optic Nerve / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D014463:Ultrasonography