Radiofrequency Monitoring of Intracranial Hemorrhage in the Neurological Intensive Care Unit: A Pilot Trial of the SENSE Device

Intracerebral hemorrhage (ICH) is a devastating form of stroke, with substantial mortality and morbidity. Hemorrhage expansion (HE) occurs in [~]40% of patients and portends worse neurologic outcome and mortality. Currently, ICH patients are admitted to the intensive care unit (ICU) and monitored for HE with neurologic exam and neuroimaging. By the time a change is detected, it may be too late to mitigate HE. There is a clinical need for a non-invasive bedside monitor of ICH. The SENSE consists of a 9-antenna array mounted around the head with driving electronics. A 913 MHz signal is transmitted by a given antenna, crosses the intracranial region, and received by the remaining 8 antennae. A complete measurement consists of one cycle with each antenna serving as the transmitting antenna. It was hypothesized that HE of [≥] 3 ml would be detected by the device. Ten ICH subjects admitted within 24 hours of stroke onset were enrolled. All patients received a diagnostic head CT (baseline), and a repeat head CT at 12 (+/- 6) hours. ICH volumes were determined by blinded neuroradiologist reading, and a significant HE from baseline was considered [≥] 3 ml. Subjects were scanned with the device every 10 minutes for up to 72 hours. Data from one subject was lost from operator error. Among the remaining nine, two experienced HE of [≥] 3ml (3 and 8.2 ml respectively). SENSE device readings were 100% concordant with the CT scan results.