TCCD Fusion Imaging to Estimate Intracranial Pressure and Tissue Displacement with Large Hemispheric Infarction

Despite breakthroughs in stroke treatment, some patients still experience large infarctions of the cerebral hemispheres resulting in mass effect and tissue displacement. The evolution of mass effect is currently monitored using serial computed tomography (CT) imaging. However, there are patients who are ineligible for transport, and there are limited options for bedside monitoring of unilateral tissue shift.

We used fusion imaging for overlaying transcranial color duplex with CT angiography. This method allows overlay of live ultrasound on top of CT or magnetic resonance imaging scans. Patients with large hemispheric infarctions were eligible to participate. Position data from the source files were used and matched with live imaging and correlation to magnetic probes on the patient's forehead and ultrasound probe. Shift of cerebral parenchyma, displacement of the anterior cerebral arteries, basilary artery and third ventricle were analyzed, as well as pressure on the midbrain, and the displacement of the basilar artery on the head were analyzed. Patients received multiple examinations in addition to standard care of treatment with CT imaging.

The sensitivity for diagnosing a shift of 3 mm with fusion imaging was 100%, with a specificity of 95%. No side effects or interactions with critical care equipment were recorded.

Fusion imaging is an easy method to access and acquire measurements for critical care patients and follow-up of tissue and vascular displacement after stroke. Fusion imaging may be a decisive support for indicating hemicraniectomy.