Pre operative evaluation of keros classification in endoscopic sinus surgery

Abstract

Disruption of mucociliary clearance, often caused by anatomic variations and mucosal
disease, is the primary pathogenic factor contributing to the persistence of symptoms and the
chronic nature of the disease1. The boundaries of the olfactory fossa are defined as follows:
medial – crista galli, inferior – cribriform plate of the ethmoid, and lateral – lateral lamella of
the ethmoid2 . Additionally, there exists an asymmetry between the olfactory fossa on the left
and right sides. It is crucial to conduct a preoperative assessment using the Keros
classification to prevent inadvertent procedures at the skull base level, as the depth of the
olfactory fossa may differ between the two sides3-5 .Chronic sinonasal diseases are prevalent
conditions necessitating surgical intervention in the field of otolaryngology. While some
diseases can be managed with medications, surgical treatment is often required. Endoscopic
sinus surgery (ESS) is the predominant approach employed for treatment currently6-8
.The Keros classification is a widely utilized method for assessing the depth of the nasal roof
preoperatively to mitigate potential life-threatening complications. The uncinate process and
attachment of the middle turbinate can be linked to various anatomical regions, occasionally
attaching directly to the nasal roof9,10. Disruption of this anatomical site can lead to severe
clinical complications such as cerebrospinal rhinorrhea and meningitis. High-resolution computed tomography (HRCT) serves as the gold standard for diagnosing paranasal sinus
conditions and adjacent structures, playing a crucial role in preoperative assessment to
prevent associated medical complications11-13. The objective is to determine the incidence of
keros classification in ethmoid sinus.