Emergency neck MRI: feasibility and diagnostic accuracy in cases of neck infection

Abstract

Background Computed tomography (CT) has traditionally been the first-line imaging method in neck emergencies such as deep neck infections. Due to superior soft-tissue contrast, magnetic resonance imaging (MRI) may be an alternative to CT, also in emergency situations. Purpose To characterize the use of routine MRI in neck emergencies, with an emphasis on clinical feasibility and diagnostic accuracy in cases of neck infection. Material and Methods We conducted a retrospective cohort study of all primary neck MRI scans performed using a 3-T MRI device during a five-year follow-up period in a tertiary emergency radiology department. Imaging data were compared with final clinical diagnosis and surgical findings as reference standards. Results The search identified 461 primary neck MRI scans, of which 334 (72%) were performed on the basis of clinical suspicion of infection. Radiological evidence of infection was observed in 95% of these scans, and at least one abscess was detected in 229 cases (72% of confirmed infection). MRI had an overall technical success rate of 95% and had high positive predictive value for both infection (0.98) and detection of abscess (0.95). Conclusion We found that emergency neck MRI can be successfully performed on most patients, and that MRI detects neck infection with a high accuracy. These results suggest that MRI may be an alternative to CT as the first or only imaging modality in neck emergencies.

Clinical and prognostic significance of emergency MRI findings in neck infections

“…We measured the maximal diameter of the abscesses from post-Gd T1-weighted images. Substantial interobserver agreement for the detection of an abscess has been shown previously [8].…”

“…Accurate evaluation becomes crucial for detecting abscesses, which usually require prompt surgical exploration. MRI was recently shown to be accurate in detecting abscesses that far exceed those previously reported for CT [ 8 ]. In the same study, the positive predictive value (PPV, fraction of patients with a positive test result who actually have the disease) for the detection of an abscess was 0.95, compared with about 0.80 previously reported for CT. Differentiation between RPE and true retropharyngeal abscess may be especially difficult with CT, with studies showing PPV in the range of 0.50 to 0.80 [ 4 , 13 – 15 ].…”

“…MRI provides excellent soft-tissue characterization, surpassing that of CT in the imaging evaluation of neck infections [ 7 ]. Although MRI is often considered time consuming and challenging for acutely ill patients, emergency neck MRI has recently shown to be feasible and to have superior diagnostic accuracy to that previously reported for CT [ 8 ].…”

MRI Findings in Acute Tonsillar Infections

“…MR imaging provides superior soft-tissue contrast compared with CT, 7,8 and emergency neck MR imaging is feasible even in acutely ill patients. 9 MR imaging can distinguish between reactive nonsuppurative edema and true abscesses in the deep neck spaces and has a high diagnostic accuracy in the detection of neck infections and abscesses. 9 Therefore, MR imaging might be useful for illustrating the spectrum of tonsillar infections.…”

The Efficacy of Pyogenic Cavity Aerobic Therapy with Negative Pressure Drainage in the Treatment of Deep Neck Space Infections

“…CT combines fast image acquisition Infection and Drug Resistance 2021:14 and precise anatomical information without field-of-view limitations. Nurminen et al 18 reported that magnetic resonance imaging (MRI) had very high diagnostic accuracy and predictive value for both infections and abscesses, whereas MRI was more complex and time-consuming to read than CT. For these reasons, CT is the first imaging examination of choice in emergency situations, especially in cases of shortness of breath. If an abscess has not yet formed or the scope is small, the patients can be followedup by CT examination or color Doppler ultrasound examination according to the general clinical situation.…”