Ultrasonic assessment of optic nerve sheath to detect increased intracranial pressure

Abstract

Purpose: Increased intracranial pressure (ICP) is one of the prevalent symptoms of trauma, especially traumatic headache, which requires quick action for the diagnosis and treatment. The optic nerve sheath diameter (ONSD) is a newly proposed technique for the detection of an increase in ICP. The aim of this study was to assess the efficacy of this new diagnostic method in patients with increased ICP induced by trauma. Methods: This prospective study was conducted between December 2016 and February 2017. The patients with traumatic headache and who had been diagnosed with increased ICP using clinical signs and computed tomography scan were compared to the voluntary healthy group. In each patient, measurements were performed employing ultrasound three times on each eye in an axial region, and the mean of these sizes was obtained as the ONSD. Results: A total of 112 participants were examined. The mean ONSD measurement of the patients and the voluntary healthy group was 6.01 ± 0.76 and 3.41 ± 0.56 mm in the right eye, 6.11 ± 0.75 and 3.39 ± 0.54 mm in the left eye, and 6.06 ± 0.75 and 4.02 ± 1.07 mm in both sides, respectively. The ONSD in the right and left sides had high and significant correlation in the patients ( r = 0.929, P < 0.000) and voluntary healthy ( r = 0.630, P < 0.000) group. The mean ONSD of one of the patients was 6.24 ± 0.56 mm, and in another patient with no clinical sign of increased ICP, the mean ONSD was 4.61 ± 0.09 mm. Conclusions: Ultrasound performed on the diaphragm of the optic nerve with acceptable sensitivity can detect patients with an increase in ICP and can be efficacious in expediting the action needed to reduce ICP. Due to the sensitivity and specificity of the ultrasound and high accuracy of the diameter of optic nerve sheath in detecting increase in ICP, as well as considering the fact that ultrasound is a noninvasive and available technique; it can be performed at the patient's bedside.

The potential of point-of-care diagnostics to optimise prehospital trauma triage: a systematic review of literature

“…Intracranial pressure increase (RICP) was defined either as a pressure of > 20 mmHg over a period of time [ 45 , 47 , 52 , 53 , 55 ] or clear signs of intracranial pressure on CT [ 46 , 48 – 51 , 54 , 56 – 59 ].…”

“…Further cut-off values for an increased ICP can be found in appendix (p.13) [ 46 – 51 , 53 , 54 , 57 – 59 ].…”

“…A significant difference between left and right ONSD values in patients was not found [ 44 ] or a significant correlation between both eyes was found [ 51 ]. The Newcastle–Ottawa scale classified one study with nine stars [ 59 ], three studies with eight stars [ 50 , 52 , 53 ], four studies with six stars [ 45 , 47 , 51 , 57 ], five studies with five stars [ 48 , 49 , 54 – 56 ] and three studies with four stars [ 44 , 46 , 58 ]. The review of the cut-off values by the quality criteria identified 5 final cut-off values that all fulfilled the outcome of increased intracranial pressure.…”

“…The "supine position" as the preferred examination position [ 44 , 46 – 49 , 51 , 53 , 54 , 58 , 59 ] could also be easily integrated into the procedure and the normally used positioning of a rescue operation. Due to the time-consuming nature of the examination, it is only recommended for GCS < 13.…”

Mean value of B-mode optic nerve sheath diameter as an indicator of increased intracranial pressure: a systematic review and meta-analysis

“… Chen 2019 [ 14 ] China Prospective 29 4.53 DelicaMVU-6300 Mixed LP Mixed 3 mm behind the globe; averaged two measurements: one sagittal and the other in the transverse plane del Saz-Saucedo 2016 [ 15 ] Spain Prospective 19 6.76 Toshiba AplioXG Mixed LP IIH Transverse plane Du 2020 [ 16 ] China Prospective 49 5.7 Sonosite ICU Inv Trauma 3 mm behind the globe; transverse plane; averaged two eyes. Geeraerts 2007 [ 17 ] France Prospective 15 6.3 HP Sonos 5500 ICU Inv Trauma 3 mm behind the globe; one sagittal and one transverse Goel 2008 [ 18 ] India Prospective 73 5.8 Unspecified Mixed CT Trauma 3 mm behind the globe; one sagittal and one transverse; averaged Hanafi 2019 [ 19 ] Iran Prospective 62 …”