Bedside Ultrasound After Decompressive Craniectomy: A New Standard?

Feasibility, Clinical Potential, and Limitations of Trans-Burr Hole Ultrasound for Postoperative Evaluation of Chronic Subdural Hematoma: A Prospective Pilot Study

BACKGROUND AND OBJECTIVES

Chronic subdural hematoma (CSDH) is commonly managed through burr hole surgery. Routine follow-up using computed tomography (CT) imaging is frequently used at many institutions, contributing to significant radiation exposure. This study evaluates the feasibility, safety, and reliability of trans-burr hole sonography as an alternative postoperative imaging modality, aiming to reduce radiation exposure by decreasing the frequency of CT scans.

METHODS

We conducted a prospective pilot study on 20 patients who underwent burr hole surgery for CSDH. Postoperative imaging included both CT and sonographic examinations through the burr hole. We assessed the ability to measure residual subdural fluid thickness under the burr hole sonographically compared with CT, the occurrence of complications, and the potential factors affecting sonographic image quality. The Pearson correlation coefficient was used to demonstrate relationships between CT and ultrasound and axial and coronal ultrasound.

RESULTS

Sonography through the burr hole was feasible in 73.5% of cases, providing measurements of residual fluid that closely paralleled CT findings, with an average discrepancy of 1.2 mm for axial and 1.4 mm for coronal sonographic views. A strong positive correlation was found between axial and coronal ultrasound ( r = 0.955), CT and axial ultrasound ( r = 0.936), and CT and coronal ultrasound ( r = 0.920). The primary obstacle for sonographic imaging was the presence of air within the burr hole or the subdural space, which typically resolved over time after surgery.

CONCLUSION

Trans-burr hole sonography emerges as a promising technique for postoperative monitoring of CSDH, with the potential to safely reduce reliance on CT scans and associated radiation exposure in selected patients. Our results support further investigation into the extended use of sonography during the follow-up phase. Prospective multicenter studies are recommended to establish the method's efficacy and to explore strategies for minimizing air presence postsurgery.

Transcranial Sonography versus CT for Postoperative Monitoring After Decompressive Craniectomy

BACKGROUND AND PURPOSE

Computed tomography (CT) is the actual gold standard diagnostic tool for monitoring patients after decompressive craniectomy. It is validated and provides a wide number of information. However, it takes time, expensive, and requires patient transportation. Transcranial sonography (TCS) could represent an alternative diagnostic tool in these patients. The aim of this study is to compare TCS versus CT scan after decompressive craniectomy in terms of diagnosing complications and costs evaluation.

METHODS

We prospectively enrolled 10 craniectomized patients who were monitored with sonography and CT. Ventricular measurements and possible complications were evaluated by two independent observers. The two methods were compared using Fisher's exact test and Spearman's Rho coefficient. A costs analysis was also conducted.

RESULTS

A good correlation coefficient (ρ) between CT and TCS was found for frontal horn dimensions (ρ .9929), median cella (ρ .9516), and third ventricle (ρ .8989). All results were statistically significant (P < .0001) and Bland-Altman plots showed no systemic biases. Fisher's exact test showed no statistically significant differences between TCS and CT for all the studied predefined complications. Cost analysis showed a 68% cost reduction in favor of TCS.

CONCLUSIONS

TCS could be a reliable alternative diagnostic tool for major complications in patients undergoing decompressive craniectomy. It could limit the number of CT scans per patient overcoming several limitations, such as costs, radiation exposure, and need to move the patient.