Complications of Frontal Sinusitis. Bibliographic Review
Authors: Santos Pedro , Costa Patricia , Almeida João , Carvalho Isabel , Sousa Cecília 
Published: October 2022

Introduction and objective: Frontal rhinosinusitis usually resolves with medical therapy. However, when the sinonasal infection persists, the anatomy of this region can lead to severe and life-threatening complications due to infection spreading beyond the sinus namely to the intracranial compartment. This review aims to highlight the more recent developments on the management of frontal rhinosinusitis and its complications, from a practical perspective that is essential to accurately diagnose these complications. Method: A review of the literature was performed by the authors. PubMed database was searched with relevant terms, which included the following: «frontal sinusitis complications», «pediatric frontal sinusitis» and «frontal sinusitis imaging». Relevant scientific treaties were also used as ancillary to this review. A comprehensive review of the English and Portuguese literature was carried out, including papers published between 2000 and 2021. Our inclusion criteria included clinical trials, expert opinion papers, literature reviews, systematic reviews and clinical guidelines. Duplicate articles, case reports or very small sample studies were excluded prior general screening. Results: Twenty-one studies met the inclusion criteria. Most of them concerned the adult population, with four papers directly addressing the pediatric population. Two clinical guidelines, one large retrospective cohort study and two systematic reviews were selected. Twelve clinical review articles and small retrospective studies were selected, comprising most of the papers addressed. Four clinical textbooks were also consulted for this review. Discussion: Morbidity and mortality from complicated sinusitis are mainly related to intracranial involvement. Although the mortality rate was higher before the era of antibiotic therapy, intracranial abscess still carries high mortality. Frontal sinusitis can be complicated by periorbital cellulitis, abscess formation, both periorbital and subperiosteal in the frontal bone anterior wall (Pott puffy tumor), and, rarely, cavernous sinus thrombosis. Intracranial complications include subdural and epidural empyema, meningitis, and intracerebral abscess. These complications will be reviewed in this paper. Conclusions: Complications of frontal sinusitis can be severe and life threatening, mainly due to the proximity of the frontal sinus with the intracranial compartment. Due to its high availability, CT frequently is the first imaging technique performed in the emergency setting. The excellent bone and high-spatial resolution make CT the preferred imaging examination in presurgical planning. However, contrast-enhanced MRI is far superior in soft-tissue evaluation and should be considered whenever an orbitary or intracranial complication is suspected. These complications are mostly treated with intravenous antibiotics and surgical drainage procedures. Early aggressive intervention has decreased morbidity and shortened hospital stay, although significant morbidity and mortality from complications can still occur.