“…Secondly, all but one study lack comparison imaging at the time of or prior to admission. The high prevalence of sinus inflammation in the general population and the absence of pre‐ICU imaging may therefore introduce bias when drawing conclusions concerning the incidence of ICU‐derived sinusitis . Finally, many studies are also limited to incomplete imaging of the paranasal sinuses (partial CT, ultrasound, or sinus X‐rays) by study design (e.g., maxillary aspirates) or confounded by the presence of facial fractures.…”