Evaluation of Anatomical Variations in Ostiomeatal Unit by Computed Tomography

  • Sushilkumar Kale Professor, Department of Radiodiagnosis
  • K Preetha Junior Resident III, Department of Radiodiagnosis
Keywords: Computed tomography, Ethmoid bulla, Functional endoscopic sinus surgery, Ostiomeatal unit, Pneumatization, Uncinate process


Introduction: The ostiomeatal unit has a lot of anatomical variations. Evaluation of these variations is important in patients who undergo computed tomography (CT) scan for their Rhinological complaints. These anatomical variants are responsible for chronic ailments like rhinosinusitis, and their knowledge is essential to not only reduce complications during procedures like functional endoscopic sinus surgery but also to explain the disease recurrence and allow surgeons to decide their operative approach.
Purpose: The purpose of the study was to evaluates and determine the incidence of anatomical variations of ostiomeatal unit on CT and to assess the relation of these variations with sinonasal mucosal diseases.
Materials and Methods: This is a prospective cross-sectional study done at the Department of Radiodiagnosis in a tertiary care center over a period of 24 months with 100 subjects having sinonasal complaints which were referred from various departments for CT scan.
Results: The attachment of the uncinate process had many variations with attachment to the lamina papyracea being 84%, attachment to the skull in 8%, attachment to the middle turbinate in 6%, and free lying in 2%. The uncinate process pneumatization was seen in 6% cases. Giant ethmoid bullae were noted in 11% cases while hypoplastic ethmoid bullae were seen in 4%. In terms of association with sinusitis, only uncinate process pneumatization was found to have a significant statistical association.
Conclusion: The most common ostiomeatal unit anatomical variant was varied attachment of the uncinate process. The least common variant noted was the uncinate process pneumatization; however, only this variant was found to have a positive correlation with sinusitis in comparison to other ostiomeatal unit variants.

Author Biographies

Sushilkumar Kale, Professor, Department of Radiodiagnosis

Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha, Maharashtra, India

K Preetha, Junior Resident III, Department of Radiodiagnosis

Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha, Maharashtra, India


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