Radiographic predictors of clinical outcome in traumatic brain injury after decompressive craniectomy

Diagnostic Value of the Combination of Ultrasonographic Optic Nerve Sheath Diameter and Width of Crural Cistern with Respect to the Intracranial Pressure in Patients Treated with Decompressive Craniotomy

BACKGROUND

The monitoring of intracranial pressure (ICP) and detection of increased ICP are crucial because such increases may cause secondary brain injury and a poor prognosis. Although numerous ultrasound parameters, including optic nerve sheath diameter (ONSD), width of the crural cistern (WCC), and the flow velocities of the central retinal artery and middle cerebral artery, can be measured in patients after hemicraniectomy, researchers have yet to determine which of these is better for evaluating ICP. This study aimed to analyze the correlation between ICP and ultrasound parameters and investigate the best noninvasive estimator of ICP.

METHODS

This observational study enrolled 50 patients with brain injury after hemicraniectomy from January 2021 to December 2021. All patients underwent invasive ICP monitoring with microsensor, transcranial, and ocular ultrasound postoperatively. We measured the ONSD including the dura mater (ONSDI), the ONSD excluding the dura mater, the optic nerve diameter (OND), the eyeball transverse diameter (ETD), the WCC, and the flow velocities in the central retinal artery and middle cerebral artery. Then, we calculated the ONSDI-OND (the difference between ONSDI and OND) and ONSDI/ETD (the ratio of ONSDI to ETD). Patients were divided into a normal ICP group (n = 35) and an increased ICP group (≥ 20 mm Hg, n = 15) according to the ICP measurements. Correlations were then assessed between the values of the ultrasound parameters and ICP.

RESULTS

The ONSDI, ONSDI-OND, and ONSDI/ETD were positively associated with ICP (r = 0.455, 0.482, 0.423 and p = 0.001, < 0.001, 0.002, respectively), whereas the WCC was negatively associated with ICP (r = - 0.586, p < 0.001). The WCC showed the highest predictive power for increased ICP (area under the receiver operating characteristic curve [AUC] = 0.904), whereas the ONSDI-OND and ONSDI also presented with acceptable predictive power among the ONSD-related parameters (AUC = 0.831, 0.803, respectively). The cutoff values for increased ICP prediction for ONSDI, ONSDI-OND, and WCC were 6.29, 3.03, and 3.68 mm, respectively. The AUC of the combination of ONSDI-OND and WCC was 0.952 (95% confidence interval 0.896-1.0, p < 0.001).

CONCLUSIONS

The ONSDI, ONSDI-OND, and WCC were correlated with ICP and had acceptable accuracy levels in estimating ICP in patients after hemicraniectomy. Furthermore, WCC showed a higher diagnostic value than ONSD-related parameters, and the combination of ONSDI-OND and WCC was a satisfactory predictor of increased ICP.

Current Status and Outcomes of Critical Traumatic Brain Injury (GCS = 3-5) in a Developing Country: A Retrospective, Registry-Based Study

BACKGROUND

Patients sustaining critical TBI [initial Glasgow Coma Scale (GCS) ≤ 5] generally have poor outcomes. Little is known about the frequency, mortality rate, and functional outcomes of such patients in Iran.

METHODS

In this retrospective, registry-based cohort study, the demographic and clinicoradiological findings of TBI patients were queried from March 21, 2017, to March 21, 2020. We included TBI patients with initial GCS of 3-5. The functional outcome was assessed using the Glasgow Outcome Score-extended 6 (GOSE-6) months after the hospital discharge. Patients were classified as having unfavorable (GOSE-6 ≤ 4) and favorable (GOSE-6 > 4) outcomes. Gathered data were compared between groups. Multivariable logistic regression analysis was done to find factors affecting the outcome.

RESULTS

Four hundred ninety-seven patients (mean age = 37.59 ± 17.89) were enrolled, and 69.2% had unfavorable outcomes. Elderly patients (age ≥ 65 years) were highly overrepresented among the unfavorable group. 48.9% had bilateral fixed dilated pupils (BDFP), who mostly attained unfavorable outcomes. The overall in-hospital mortality rate was 50.3%. The in-hospital mortality rate was appalling among elderly patients with BFDP and GCS 3( 90%) and GCS 4(100%). Age ≥ 65 years [odds ratio (OR) 3.45, 95% confidence interval (CI) 1.19-10.04], and BFDP (OR 4.48, 95% CI 2.60-7.73) increase the odds of unfavorable outcomes according to the regression analysis.

CONCLUSION

The survival rate and favorable outcomes of critical TBI patients are generally poor. However, we believe that the neurotrauma surgeons should discuss with patients' proxies and explain the clinical conditions and possible outcomes.