Value of bedside real-time ultrasound measurement of optic nerve sheath diameter combined with serum matrix metalloproteinase-9 and neutrophil-to-lymphocyte ratio for increased intracranial pressure after surgery in patients with severe craniocerebral injury

Objective To evaluate the clinical value of bedside ultrasonographic measurement of optic nerve sheath diameter (ONSD) combined with serum matrix metalloproteinase-9 (MMP-9) and neutrophil-to-lymphocyte ratio (NLR) in assessing postoperative intracranial hypertension in patients with severe traumatic brain injury.

Methods A total of 100 patients with severe traumatic brain injury were enrolled as study subjects. According to postoperative intracranial pressure status, the patients were divided into normal group (n=33) and elevated group (n=67). ONSD, MMP-9 and NLR levels were compared between the two groups. The correlations among ONSD, serum MMP-9 and NLR in the elevated group were analyzed. The influencing factors of postoperative intracranial hypertension in patients with severe traumatic brain injury were evaluated. Receiver operating characteristic (ROC) curve analysis was performed to assess the diagnostic value of ONSD combined with serum MMP-9 and NLR for postoperative intracranial hypertension.

Results ONSD, serum MMP-9 and NLR levels were significantly higher in the elevated group than those in the normal group (P < 0.05). ONSD was positively correlated with MMP-9 (r=0.367, P=0.002), ONSD was positively correlated with NLR (r=0.419, P < 0.01), and MMP-9 was positively correlated with NLR (r=0.324, P=0.007). Elevated ONSD, serum MMP-9 and NLR were risk factors for increased intracranial pressure after severe craniocerebral injury surgery (P < 0.05). The area under the curve for evaluation of postoperative intracranial pressure increase in patients with severe craniocerebral injury by combination of ONSD, serum MMP-9 and NLR was 0.976 (95%CI, 0.952 to 1.000), the sensitivity was 91.04%, and the specificity was 93.94%. The combined evaluation value of ONSD, serum MMP-9 and NLR for increased intracranial pressure after surgery in patients with severe craniocerebral injury was higher (Z_{combined with-ONSD}=3.453, P=0.001, Z_{combined with-MMP-9}=3.637, P < 0.001, Z_{combined with-NLR}=2.654, P=0.008).

Conclusion In patients with increased intracranial pressure after severe craniocerebral injury surgery, their levels of ONSD, serum MMP-9 and NLR increase, and the increase of the three indicators will increase the risk of increased intracranial pressure after surgery. The combined detection of the three indicators has certain value in evaluating the increase of intracranial pressure in patients after surgery.