Portable, Bedside, Low-field Magnetic Resonance Imaging in an Intensive Care Setting for Intracranial Hemorrhage (270)

Objective: To obtain preliminary data regarding the ability of a bedside POC MRI scanner to detect ICH.

Background: Radiographic diagnosis of intracranial hemorrhage (ICH) is a critical determinant of stroke care pathways requiring patient transport to a neuroimaging suite. Advances in low-field MRI have made it possible to obtain clinically useful imaging at the point of care (POC).

Design/Methods: We studied 36 patients with a diagnosis of ICH (n=18) or ischemic stroke (n=18). Five blinded readers independently evaluated T2W and FLAIR exams acquired prospectively on a 64 mT, portable bedside MRI system (Hyperfine Research, Inc). Kappa coefficients (κ) were calculated to determine inter-rater agreement. Ground truth was obtained from the clinical report of the closest conventional imaging study (17.9 ± 10.4 hours) and verified by a core reader. For each exam, majority consensus among raters was used to determine sensitivity.

Results: ICH volume ranged from 4 to 101 cc (median of 13 cc). Exams were acquired within 7 days of symptom onset (51.1 ± 28.8 hours). A pathologic lesion was identified on every exam with 100% sensitivity. Sensitivity for distinguishing any hemorrhage was 89% and specificity was 83%. The mean sensitivity and specificity for individual raters was 79% and 69%, respectively. When limited to supratentorial hemorrhage, consensus sensitivity was 94%. For ICH cases detected by all raters (n=9), there was 100% accuracy for localizing the bleed (lobar vs. non-lobar) with perfect agreement among raters (κ = 1, p <0.0001). There was substantial agreement for identifying intraventricular hemorrhage (IVH) (κ = 0.72, p < 0.0001). Sensitivity for IVH was 100% based on rater consensus.

Conclusions: These data suggest that low-field, POC MRI may be used to detect hemorrhagic stroke at the bedside. Further work is needed to evaluate this approach in the hyperacute setting and across a wide range of ICH characteristics.

Disclosure: Dr. Shah has received research support from Hyperfine Research, Inc.Dr. Cahn has nothing to disclose. Dr. By has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Hyperfine Research, Inc. Dr. By holds stock and/or stock options in Hyperfine Research, Inc. Dr. Welch has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Hyperfine Research, Inc.. Dr. Welch holds stock and/or stock options in Hyperfine Research, Inc. Dr. Sacolick has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Hyperfine Research, Inc.. Dr. Sacolick holds stock and/or stock options in Hyperfine Research, Inc. Dr. Yuen has received research support from Hyperfine Research, Inc. Dr. Mazurek has received research support from Hyperfine Research, Inc. Dr. Wira has nothing to disclose. Dr. Leasure has nothing to disclose. Dr. Matouk has nothing to disclose. Dr. Ward has nothing to disclose. Dr. Payabvash has nothing to disclose. Dr. Beekman has nothing to disclose. Dr. Brown has received research support from AHA. Dr. Falcone has nothing to disclose. Dr. Gobeske has nothing to disclose. Dr. Petersen has nothing to disclose. Dr. Jasne has nothing to disclose. Dr. Sharma has nothing to disclose. Dr. Schindler has nothing to disclose. Dr. Sansing has nothing to disclose. Dr. Gilmore has nothing to disclose. Dr. Sze has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Hyperfine. Dr. Sze has received research support from Hyperfine. Dr. Rosen has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Hyperfine Research, Inc. Dr. Rosen has received royalty, license fees, or contractual rights payments from BlinkAI. Dr. Rosen holds stock and/or stock options in BlinkAI. Dr. Rosen has received research support from GE Healthcare. Dr. Kimberly has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Biogen. Dr. Kimberly has received research support from Biogen. Dr. Sheth has received royalty, license fees, or contractual rights payments from Alva Health. Dr. Sheth holds stock and/or stock options in Alva Health which sponsored research in which Dr. Sheth was involved as an investigator. Dr. Sheth has received research support from Hyperfine, Novartis, Biogen, Bard, Zoll.