Advertisement

Correlation of optic nerve sheath diameter measurements by computed tomography and magnetic resonance imaging

Published:September 19, 2013DOI:https://doi.org/10.1016/j.ajem.2013.07.028

      Abstract

      Background

      Traditionally, intracranial pressure is measured by direct ventriculostomy, which is invasive. Noninvasive measures such as bedside ultrasound and magnetic resonance imaging have been advocated and utilized recently to assess the intracranial pressure. The role of this study is to determine the degree of agreement between measurements of the optic nerve sheath diameter by computed tomography (CT) and magnetic resonance imaging (MRI).

      Materials and Methods

      Retrospective chart review of 100 consecutive patients who had both MRI and CT scan of the head from January 1, 2011, until March 31, 2013, at our center was performed. A discrepancy of 0.2 mm between the 2 measurements was set as acceptable difference. The measurements of optic nerve sheath diameter (ONSD) were compared for agreement between the 2 modalities using the method by Bland and Altman.

      Results

      A total of 100 patients with both MRI and CT scan of the head were selected. Of these 100 patients, 24 were male and 76 were female. The average age was 63 years. No ONSD abnormality was detected in any of the patients. The discrepancy in measurements of the ONSD between CT and MRI in transverse plane was less than the predetermined cut-off value of 0.2 mm. Within-subject variance was estimated at 0.0058 for both CT and MRI.

      Conclusion

      Comparable results without significant discrepancy as predetermined by the study groups were obtained from CT scan. Measurement of ONSD by CT scan can be used to indirectly asses the intracranial pressure in addition to clinical assessment and other signs of increased intracranial pressure on CT scan.
      To read this article in full you will need to make a payment
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'

      Subscribe:

      Subscribe to The American Journal of Emergency Medicine
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect

      References:

        • Blaivas M.
        Bedside emergency department ultrasonography in the evaluation of ocular pathology.
        Acad Emerg Med. 2000; 7: 947-950
        • Cammarata G.
        • et al.
        Ocular ultrasound to detect intracranial hypertension in trauma patients.
        J Trauma. 2011; 71: 779-781
        • Dubost C.
        • et al.
        Optic nerve sheath diameter used as ultrasonographic assessment of the incidence of raised intracranial pressure in preeclampsia: a pilot study.
        Anesthesiology. 2012; 116: 1066-1071
        • Helmke K.
        • Hansen H.C.
        Fundamentals of transorbital sonographic evaluation of optic nerve sheath expansion under intracranial hypertension I. Experimental study.
        Pediatr Radiol. 1996; 26: 701-705
      1. Here's what new ED ultrasound guidelines say. ED Manag 14, 5–7; suppl 1–9 (2002).

        • Luerssen T.G.
        Intracranial pressure: current status in monitoring and management.
        Semin Pediatr Neurol. 1997; 4: 146-155
        • Lundberg N.
        Continuous recording and control of ventricular fluid pressure in neurosurgical practice.
        Acta Psychiatr Scand Suppl. 1960; 36: 1-193
        • Lundberg N.
        • Troupp H.
        • Lorin H.
        Continuous recording of the ventricular-fluid pressure in patients with severe acute traumatic brain injury. A preliminary report.
        J Neurosurg. 1965; 22: 581-590
        • Miller J.D.
        ICP monitoring—current status and future directions.
        Acta Neurochir (Wien). 1987; 85: 80-86
        • Mizutani T.
        • Manaka S.
        • Tsutsumi H.
        Estimation of intracranial pressure using computed tomography scan findings in patients with severe head injury.
        Surg Neurol. 1990; 33: 178-184
        • Tabaddor K.
        • Danziger A.
        • Wisoff H.S.
        Estimation of intracranial pressure by CT scan in closed head trauma.
        Surg Neurol. 1982; 18: 212-215
        • Miller M.T.
        • et al.
        Initial head computed tomographic scan characteristics have a linear relationship with initial intracranial pressure after trauma.
        J Trauma. 2004; 56 ([discussion 972–3]): 967-972
        • Kimberly H.H.
        • Shah S.
        • Marill K.
        • Noble V.
        Correlation of optic nerve sheath diameter with direct measurement of intracranial pressure.
        Acad Emerg Med. 2008; 15: 201-204
        • Geeraerts T.
        • et al.
        Use of T2-weighted magnetic resonance imaging of the optic nerve sheath to detect raised intracranial pressure.
        Crit Care. 2008; 12: R114
        • Kimberly H.H.
        • Noble V.E.
        Using MRI of the optic nerve sheath to detect elevated intracranial pressure.
        Crit Care. 2008; 12: 181
        • Soldatos T.
        • et al.
        Optic nerve sonography in the diagnostic evaluation of adult brain injury.
        Crit Care. 2008; 12: R67
        • Moretti R.
        • Pizzi B.
        • Cassini F.
        • Vivaldi N.
        Reliability of optic nerve ultrasound for the evaluation of patients with spontaneous intracranial hemorrhage.
        Neurocrit Care. 2009; 11: 406-410
        • Bland J.M.
        • Altman D.G.
        Agreed statistics: measurement method comparison.
        Anesthesiology. 2012; 116: 182-185
        • Bland J.M.
        • Altman D.G.
        Statistical methods for assessing agreement between two methods of clinical measurement.
        Lancet. 1986; 1: 307-310
        • Brazdzionyte J.
        • Macas A.
        Bland-Altman analysis as an alternative approach for statistical evaluation of agreement between two methods for measuring hemodynamics during acute myocardial infarction.
        Medicina (Kaunas). 2007; 43: 208-214
        • Ghajar J.
        Intracranial pressure monitoring techniques.
        New Horiz. 1995; 3: 395-399
        • Pople I.K.
        • Muhlbauer M.S.
        • Sanford R.A.
        • Kirk E.
        Results and complications of intracranial pressure monitoring in 303 children.
        Pediatr Neurosurg. 1995; 23: 64-67
        • Shapiro S.
        • Bowman R.
        • Callahan J.
        • Wolfla C.
        The fiberoptic intraparenchymal cerebral pressure monitor in 244 patients.
        Surg Neurol. 1996; 45: 278-282
        • Geeraerts T.
        • Merceron S.
        • Benhamou D.
        • Vigue B.
        • Duranteau J.
        Non-invasive assessment of intracranial pressure using ocular sonography in neurocritical care patients.
        Intensive Care Med. 2008; 34: 2062-2067