Association of ultra-early diffusion-weighted magnetic resonance imaging with neurological outcomes after out-of-hospital cardiac arrest

Abstract

Background This study aimed to investigate the association between ultra-early (within 6 h after return of spontaneous circulation [ROSC]) brain diffusion-weighted magnetic resonance imaging (DW-MRI) and neurological outcomes in comatose survivors after out-of-hospital cardiac arrest. Methods We conducted a registry-based observational study from May 2018 to February 2022 at a Chungnam national university hospital in Daejeon, Korea. Presence of high-signal intensity (HSI) (PHSI) was defined as a HSI on DW-MRI with corresponding hypoattenuation on the apparent diffusion coefficient map irrespective of volume after hypoxic ischemic brain injury; absence of HSI was defined as AHSI. The primary outcome was the dichotomized cerebral performance category (CPC) at 6 months, defined as good (CPC 1–2) or poor (CPC 3–5). Results Of the 110 patients (30 women [27.3%]; median (interquartile range [IQR]) age, 58 [38–69] years), 48 (43.6%) had a good neurological outcome, time from ROSC to MRI scan was 2.8 h (IQR 2.0–4.0 h), and the PHSI on DW-MRI was observed in 46 (41.8%) patients. No patients in the PHSI group had a good neurological outcome compared with 48 (75%) patients in the AHSI group. In the AHSI group, cerebrospinal fluid (CSF) neuron-specific enolase (NSE) levels were significantly lower in the group with good neurological outcome compared to the group with poor neurological outcome (20.1 [14.4–30.7] ng/mL vs. 84.3 [32.4–167.0] ng/mL, P < 0.001). The area under the curve for PHSI on DW-MRI was 0.87 (95% confidence interval [CI] 0.80–0.93), and the specificity and sensitivity for predicting a poor neurological outcome were 100% (95% CI 91.2%–100%) and 74.2% (95% CI 62.0–83.5%), respectively. A higher sensitivity was observed when CSF NSE levels were combined (88.7% [95% CI 77.1–95.1%]; 100% specificity). Conclusions In this cohort study, PHSI findings on ultra-early DW-MRI were associated with poor neurological outcomes 6 months following the cardiac arrest. The combined CSF NSE levels showed higher sensitivity at 100% specificity than on DW-MRI alone. Prospective multicenter studies are required to confirm these results.

Optimal timing of ultra-early diffusion-weighted MRI in out-of-hospital cardiac arrest survivors: A retrospective multicenter cohort study

“…Ultra-early DW-MRI signal alterations can differ based on the severity of hypoxia during cardiac arrest and the scanning time [14,15,34] . Unlike cerebral infarction, ultra-early DW-MRI is performed after the blood ow is restored throughout the brain following cardiac arrest-induced HIBI.…”

“…Prolonged low-ow time and non-shockable rhythm reduce the need to consider scan-interval.established [18] . However, HSIs on ultra-early DW-MRI is not consistently observed in patients with poor neurological outcomes due to its time-dependent nature [14][15][16][17] . Furthermore, HSIs on ultra-early DW-MRI is in uenced by factors including the severity, duration, and progression of oxygen deprivation, as well as the absence of blood supply [18][19][20][21][22][23][24][25] .We hypothesized that certain clinical factors associated with HIBI might in uence HSI-presence on ultraearly DW-MRI, thereby affecting the determination of the optimal timing for scanning.…”

“…established [18] . However, HSIs on ultra-early DW-MRI is not consistently observed in patients with poor neurological outcomes due to its time-dependent nature [14][15][16][17] . Furthermore, HSIs on ultra-early DW-MRI is in uenced by factors including the severity, duration, and progression of oxygen deprivation, as well as the absence of blood supply [18][19][20][21][22][23][24][25] .…”

Quantitative analysis of apparent diffusion coefficients to predict neurological prognosis in cardiac arrest survivors: an observational derivation and internal–external validation study

“…For cardiac arrest survivors, the accurate prediction of neurological outcomes serves as an important basis for communicating the patient’s condition to the family and establishing future treatment plans [ 1 – 3 ]. The current international guidelines for post-cardiac arrest care include multiple modalities, including brain imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI) [ 4 , 5 ].…”

“…Furthermore, a Korean external validation study reported that a “poor” diffusion-weighted image (DWI) had the highest sensitivity (78%) for predicting poor neurological outcomes, with a 0% false-positive rate (FPR) [ 9 ]. Despite the benefits of brain MRI, the qualitative definition in the guidelines lacks objectivity and reproducibility, limiting its use in clinical practice [ 1 , 9 – 11 ].…”