Surgical extent in chronic rhinosinusitis stratified by the LOEM system: systematic review and meta-analysis

Endoscopic sinus surgery (ESS) is widely used for chronic rhinosinusitis (CRS), but the optimal surgical extent remains unclear. The Lamella Ostium Extent Mucosa (LOEM) system provides a standardized framework to stratify surgical procedures and improve comparability. This study aimed to compare outcomes of limited versus extensive ESS and to explore results according to LOEM categories.

A systematic review and meta-analysis were conducted following PRISMA guidelines. PubMed, Embase, Cochrane Library, Web of Science, and Scopus were searched through April 2025. Eligible studies included adults with CRS undergoing ESS comparing limited and extensive surgical approaches. Outcomes included quality of life (SNOT-22), symptom severity (VAS), recurrence, and revision surgery. Procedures were reclassified according to the LOEM system by consensus.

Thirteen studies involving 2,024 patients were included. Extended procedures (LOEM 2-4) were associated with fewer revisions, lower recurrence rates, and greater SNOT-22 improvement compared with limited surgery (LOEM 1). The most extensive approach (LOEM 4) showed the highest symptom improvement.

More extensive ESS was associated with superior outcomes in CRS, including lower revision and recurrence rates and greater symptom relief. While the primary objective was to compare limited and extensive approaches, retrospective application of the LOEM classification provided a structured framework that not only confirmed these trends but also enabled more granular comparisons across surgical subtypes, from conservative functional surgery (LOEM 1-2) to radical and regenerative techniques (LOEM 3-4).