Clinical Implications and Prognostic Value of Mastoid Effusion in the Management of Aneurysmal Subarachnoid Hemorrhage

Junhyung Kim¹Sohyun Kim^2*Changki Jang³Hyun Jin Han¹Keun Young²Jung Jae Kim¹Yong Bae Kim¹Jiwoong Oh^4*

• ¹Department of Neurosurgery, College of Medicine, Yonsei University, Seoul, Republic of Korea
• ²Department of Physiology, College of Medicine, Yonsei University, Seoul, Republic of Korea
• ³Yongin Severance Hospital, College of Medicine, Yonsei University, Seoul, Seoul, Republic of Korea
• ⁴College of Medicine, Yonsei University, Seoul, Republic of Korea

The clinical significance of mastoid effusion (ME) in intensive care unit (ICU) patients has not been well elucidated. Recently, an association between ME and intracranial pressure (ICP) has been reported. We aimed to investigate the clinical implications of ME occurrence in the management of aneurysmal subarachnoid hemorrhage (aSAH) patients and its association with the prognosis.Methods: Data for patients aged > 18 treated for aSAH in a single institution between January 2020 and December 2022 were retrospectively reviewed. Brain CT or MRI images obtained within the first 14 days after the onset of SAH were evaluated for the presence of ME defined as opacification or air-fluid level in the mastoid air cells. We reviewed the patients' demographic information, neurological and medical status at admission, aneurysm and treatment characteristics and clinical outcomes, and analyzed their association with the occurrence of ME.Results: A total of 114 patients was included for the study. ME was observed in 40 patients (34.5%) within the first 14 days, at a mean of 5.0±3.5 days after the onset of SAH. In multivariate analysis, patients with ME were associated with a higher incidence of tracheostomy (Odds ratio [OR] 10.034, p = 0.024), radiologic vasospasm (OR 4.987, p = 0.018), higher APACHE II score (OR 1.138, p = 0.013), and a poor clinical outcome (OR 4.289, p = 0.041) defined as modified Rankin Scale > 2 at 90 days. Poor clinical outcome was independently associated with ME (OR 5.003, p = 0.006).This study demonstrated that ME was observed in 34.5% of aSAH patients, and was associated with poor clinical outcomes. ME may serve as a simple and useful prognostic factor for predicting poor outcomes in aSAH patients.