Ultrasonographic Optic Nerve Sheath Diameter and Brain Computed Tomography Scan

Sayyed Majid Sadrzadeh; Behrang Rezvani Kakhki; Farzaneh Ghafourian Nasab; Elham Pishbin

Ultrasonographic Optic Nerve Sheath Diameter and Brain Computed Tomography Scan

Authors

Sayyed Majid Sadrzadeh Department of Emergency Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, ‎Mashhad, Iran.‎
Behrang Rezvani Kakhki Department of Emergency Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, ‎Mashhad, Iran.‎
Farzaneh Ghafourian Nasab Student research committee, Mashhad University of Medical Sciences, Mashhad, Iran‎.
Elham Pishbin Department of Emergency Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

Keywords:

CT-scan, Intracranial pressure, Optic nerve sonography, Lumbar puncture

Abstract

Background: Increases in intracranial pressure (ICP) may damage the brain by compression of its structures or restriction of its blood flow, and its diagnosis and treatment diminish brain injury. The goal of our study was the evaluation of the relationship between optic nerve sheath diameter and intracranial pressure, and CT-scan findings.

Method: In this cross-sectional study, patients referred to Imam Reza emergency department requiring CT-scan and LP, were enrolled. After considering the exclusion criteria, all patients underwent optic nerve sonography and CT-scan and if there was not any contraindication, LP was done for them. If CSF was measured at more than 20 mmHg, it was considered high.

Results: Mean age of participants was 60.26 years old. Thirty-two patients were male and 18 cases were female. Mean GCS amount was 12.24. There was not any significant difference in this respect, between the patients with normal and abnormal CT findings (P> 0.05). Mean diameter of the optic nerve in the right eye in the patients with normal and abnormal CT findings were 3.95 mm and 5.52 mm; respectively. These amounts were 3.96 mm and 5.51 for the left eye; respectively. Mann-Whitney test revealed a statistically significant difference between the two groups based on the diameter of the optic nerve in the right eye, left eye, and average (P <0.001). Mean CSF pressure was 10.62 mmHg in the normal CT group and 14.65 mmHg in the abnormal CT group. The difference was significant between the two groups in this regard (P = 0.001). Pearson's correlation factor which showed a correlation between CSF pressure and the mean diameter of optic nerve was 0.734 which shows a direct correlation between these two variables (p <0.001).

Conclusions: This study provided some baseline data on optic nerve sheath diameter ultrasonography measures in cases with elevated intracranial pressure in the emergency ward.

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Ultrasonographic Optic Nerve Sheath Diameter and Brain Computed Tomography Scan