Radiological prognostication in patients with head trauma requiring decompressive craniectomy: Analysis of optic nerve sheath diameter and Rotterdam CT Scoring System

Traumatic Brain Injury in Select Low- and Middle-Income Countries: A Narrative Review of the Literature

Low- and middle-income countries (LMICs) experience the majority of traumatic brain injuries (TBIs), yet few studies have examined the epidemiology and management strategies of TBI in LMICs. The objective of this narrative review is to discuss the epidemiology of TBI within LMICs, describe the adherence to Brain Trauma Foundation (BTF) guidelines for the management of severe TBI in LMICs, and document TBI management strategies currently used in LMICs. Articles from January 1, 2009 to September 30, 2021 that included patients with TBI greater than 18 years of age in low-, low middle-, and high middle-income countries were queried in PubMed. Search results demonstrated that TBI in LMICs mostly impacts young males involved in road traffic accidents. Within LMICs there are a myriad of approaches to managing TBI with few randomized controlled trials performed within LMICs to evaluate those interventions. More studies are needed in LMICs to establish the effectiveness and appropriateness of BTF guidelines for managing TBI and to help identify methods for managing TBI that are appropriate in low-resource settings. The problem of limited pre- and post-hospital care is a bigger challenge that needs to be considered while addressing management of TBI in LMICs.

Prognostic Value of Initial Diagnostic Imaging Findings for Patient Outcomes in Adult Patients with Traumatic Brain Injury: A Systematic Review and Meta-Analysis

INTRODUCTION

Termed the "silent epidemic," traumatic brain injury (TBI) is one of the greatest global contributors not only to post-traumatic death but also to post-traumatic long-term disability. This systematic review and meta-analysis aims to specifically evaluate the prognostic value of features on initial imaging completed within 24 h of arrival in adult patients with TBI.

METHOD

The authors followed the PRISMA 2020 checklist for systematic review and meta-analysis design and reporting. Comprehensive searches of the Medline and Embase databases were carried out. Two independent readers extracted the following demographic, clinical and imaging information using a predetermined data abstraction form. Statistics were performed using Revman 5.4.1 and R version 4.2.0. For pooled data in meta-analysis, forest plots for sensitivity and specificity were created to calculate the diagnostic odds ratio (DOR). Summary receiver operating characteristic (SROC) curves were generated using a bivariate model, and diagnostic accuracy was determined using pooled sensitivity and specificity as well as the area under the receiver operator characteristic curve (AUC).

RESULTS

There were 10,733 patients over the 19 studies. Overall, most of the studies included had high levels of bias in multiple, particularly when it came to selection bias in patient sampling, bias in controlling for confounders, and reporting bias, such as in reporting missing data. Only subdural hematoma (SDH) and mortality in all TBI patients had both an AUC with 95% CI not crossing 0.5 and a DOR with 95% CI not crossing 1, at 0.593 (95% CI: 0.556-0.725) and 2.755 (95% CI: 1.474-5.148), respectively.

CONCLUSION

In meta-analysis, only SDH with mortality in all TBI patients had a moderate but significant association. Given the small number of studies, additional research focused on initial imaging, particularly for imaging modalities other than NECT, is required in order to confirm the findings of our meta-analysis and to further evaluate the association of imaging findings and outcome.

Role of the optic nerve sheath diameter in the assessment of the effectiveness of decompressive surgery after malignant middle cerebral artery infarction

BACKGROUND

After a case of stroke, intracranial pressure (ICP) must be measured and monitored, and the gold standard method for that is through an invasive technique using an intraventricular or intraparenchymal device. However, The ICP can also be assessed through a non-invasive method, comprised of the measurement of the optic nerve sheath diameter (ONSD) through ultrasound (US).

OBJECTIVE

To evaluate the ICP of patients who underwent wide decompressive craniectomy after middle cerebral artery (MCA) infarction via preoperative and postoperative ONSD measurements.

METHODS

A total of 17 patients, aged between 34 and 70 years, diagnosed with malignant MCA infarction with radiological edema and mid-line shift, who underwent decompressive surgery, were eligible. From the records, we collected data on age, sex, preoperative and postoperative Glasgow Coma Scale (GCS) scores, National Institutes of Health Stroke Scale (NIHSS) score, the degree of disability in the preoperative period and three months postoperatively through the scores on the Modified Rankin Scale (MRS), and the preoperative and postoperative midline shift measured by computed tomography (CT) scans of the brain.

RESULTS

Preoperatively, the mean GCS score was of 8 (range: 7.7-9.2), whereas it was found to be of 12 (range 10-14) on the first postoperative day (p = 0.001). The mean preoperative NIHSS score was of 21.36 ± 2.70 and, on the first postoperative day, it was of 5.30 ± 0.75 (p < 0.001). As for the midline shift, the mean preoperative value was of 1.33 ± 0.75 cm, and, on the first postoperative day, 0.36 ± 0.40 cm (p < 0.001). And, regarding the ONSD, the mean preoperative measurement was of 5.5 ± 0.1 mm, and, on the first postoperative day, it was of 5 ± 0.9 mm (p < 0.001).

CONCLUSION

The ocular US measurement of the ONSD for the preoperative and postoperative monitoring of the ICP seems to be a practical and useful method.

Optic nerve sheath diameter measurement for predicting raised intracranial pressure in adult patients with severe traumatic brain injury: A meta-analysis

OBJECTIVE

To evaluate and compare the diagnostic feasibility of measuring the optic nerve sheath diameter (ONSD), via brain computed tomography (CT) and ocular ultrasonography (US) for prediction of raised intracranial pressure (ICP) in severe traumatic brain injury (TBI) patients.

METHODS

The PubMed and EMBASE databases were searched for studies assessing the diagnostic accuracy of brain CT or ocular US for predicting raised ICP. Bivariate and hierarchical summary receiver operating characteristic modeling were performed to evaluate and compare the diagnostic feasibility of measuring the ONSD in adult patients with severe TBI according to modality (ocular US vs. brain CT).

RESULTS

Five studies (four with ocular US and one with brain CT) were included. The ONSD had a pooled sensitivity of 0.91, pooled specificity of 0.77, and area under the HSROC curve of 0.92 for predicting raised ICP. More importantly, studies using ocular US found an almost equal sensitivity (0.91 vs. 0.90; p = .35) and higher specificity (0.82 vs. 0.58; p = .01) than those using brain CT.

CONCLUSIONS

Measurement of the ONSD may be a useful method for predicting raised ICP in adult patients with severe TBI.

Optic nerve sheath diameter measurement for predicting raised intracranial pressure in pediatric patients: A systematic review and meta-analysis

Background and objectives:

No previous studies have investigated the relationship between the optic nerve sheath diameter and raised intracranial pressure in pediatric patients or have evaluated the usefulness of optic nerve sheath diameter in ocular ultrasound and brain computed tomography/magnetic resonance imaging. This study aimed to meta-analyze the diagnostic performance of optic nerve sheath diameter for the diagnosis of raised intracranial pressure in pediatric patients.

Methods:

A database search of PubMed and EMBASE was performed to identify relevant studies. Bivariate modeling and hierarchical summary receiver operating characteristics modeling were performed to evaluate diagnostic performance. A pooled diagnostic odds ratio with a 95% confidence interval, not including 1, was considered informative. Subgroup analysis was performed according to the modality (ocular ultrasound vs brain computed tomography/magnetic resonance imaging). We performed meta-regression analyses for heterogeneity exploration.

Results:

Eleven studies involving 546 patients were included. According to pooled diagnostic odds ratios, optic nerve sheath diameter was informative for the evaluation of raised intracranial pressure (diagnostic odds ratio, 47; 95% confidence interval, 11–206). Optic nerve sheath diameter showed a pooled sensitivity of 0.88 (95% confidence interval, 0.79–0.94), a pooled specificity of 0.86 (95% confidence interval, 0.70–0.95), and an area under the hierarchical summary receiver operating characteristics curve of 0.93 (95% confidence interval, 0.91–0.95) for the diagnosis of raised intracranial pressure. According to the subgroup analysis, ocular ultrasound (sensitivity, 0.91 (95% confidence interval, 0.81–0.96); specificity, 0.86 (95% confidence interval, 0.65–0.96)) showed higher sensitivity and comparable specificity than optic nerve sheath diameter measured on brain computed tomography/magnetic resonance imaging (sensitivity, 0.75 (95% confidence interval, 0.51–0.99); specificity, 0.91 (95% confidence interval, 0.74–1.00)). On meta-regression analysis, the study design, number of patients, and reference standard were the sources of heterogeneity.

Conclusion:

Optic nerve sheath diameter may be a useful method for predicting raised intracranial pressure in pediatric patients. We recommend that the measurement of optic nerve sheath diameter should be performed using ocular ultrasound for a more accurate diagnosis of raised intracranial pressure in pediatric patients.

Outcome of Decompressive Craniectomy in Traumatic Closed Head Injury

Objective:

The aim of the current study was to observe functional outcomes of patients undergoing decompressive craniectomy (DC) for raised intracranial pressure (ICP) after blunt head injury and to assess possible predictive factors.

Methodology:

This study was a prospective cohort study which was conducted at Aga Khan University Hospital, Karachi over a period of 2 years (January 2015–December 2016). Adult patients, aged between 15 and 65 years of both genders undergoing DC during the study period were selected. Outcomes of DC were assessed at an interval of 3 months following injury using the Glasgow outcome score. The data were analyzed on IBM statistics SPSS version 21.

Results:

Seventy-two patients underwent DC for raised and refractory ICP. Glasgow Outcome Scale (GOS) at discharge, 1-month and 3-month follow-up were reported. GOS at 3-month follow-up showed 21 patients (29.2%) patients had a good recovery, moderate disability was reported in 16 patients (22.2%), and severe disability in 12 patients (16.7%), persistent vegetative state was seen in five patients (6.9%). Eighteen patients had in hospital mortality (25.0%). Tracheostomy and sphenoid fractures were found to be negative predictors of good functional outcome.

Conclusions:

DC is associated with an in hospital mortality of 25.0%. Favorable outcomes were seen in 51.4% patients. Tracheostomy and sphenoid fractures were negative predictors of good functional outcome. The results are comparable to international literature.

A Novel Triage Tool: Optic Nerve Sheath Diameter in Traumatic Brain Injury and its Correlation to Rotterdam Computed Tomography (CT) Scoring

Background

Optic nerve sheath diameter (ONSD) evaluated in CT imaging as well as Rotterdam CT Score (RCTS) are proven independent predictors of outcome in patients with traumatic brain injury (TBI). To date, no study has correlated ONSD on admission CT scan with RCTS.

Material/Methods

Retrospective cohort study comprised of consecutive patients undergoing CT imaging for traumatic brain injury recruited between January and October 2015. Bilateral ONSD was measured 3 mm behind the eyeball in axial and sagittal planes and mean value was calculated. RCTS was assessed on the same CT images, bias was eliminated by blinding RCTS to ONSD measurement.

Results

150 patients were included; mean age in the group was 42.94±16.7 years. ONSD in mild TBI, RCTS 2 and 3 were 3.3 mm (SD 0.39 mm) and 4.1 mm (0.047 mm), respectively. Mean ONSD in moderate and severe TBI (RCTS score 4 and above) was 4.83 mm and above, SD 0.4 mm. Mean ONSD correlated with occurrence of diffuse cerebral oedema, presence of subdural and extradural hematoma; however in isolation there was no statistical significance.

Conclusions

Higher ONSD was observed in patients with moderate and severe TBI, correlating with admission RCTS of 4 and above. Subsequent increase in ONSD was also found with increase in RCTS. ONSD could serve as an initial triage tool in the emergency department as well as a method of determining the need for sequential CT in patients with mild TBI.