A Study on Anatomical Variations of Nasal Cavity Using CT Scan Images among South Indian Population

Abstract

Introduction

Sinonasal diseases are global health problems that are frequently seen in rhinological practice. Chronic rhinosinusitis (CRS) is one of the leading causes of morbidity in the developing countries. Computerized tomographic imaging (CT) of the paranasal region has become an indispensable tool for the endoscopic sinonasal surgery. The present study was planned with two objectives: 1) To identify the distribution of anatomical variations in the sinonasal region for CRS group and control group using CT scan. 2) To find the association between anatomical variations in the sinonasal region and CRS among the study groups.

Materials & methods

The study was carried out among 800 participants (cases, i.e., patients with CRS n=400 and controls n=400) representing the south Indian population. Each sub group comprised of 200 males and 200 females. The data collection was done from the CT images, which scanned the anatomical variations of the sinonasal region.

Results

There was a higher incidence of bilateral CRS in maxillary sinuses 150 (74.6%) in males and unilateral maxillary sinusitis 40 (19.9%) in females of the cases group. Among the males of the cases group, the absence of patency in osteomeatal complex and frontal sinus drainage pathway, was seen among 76 (37.8%) and 68 (33.8%) participants, respectively.

Higher bilateral presence ofconcha bullosa, accessory septa within the maxillary sinus and onodi cell was seen among the males and females of the cases group. Among the anatomical variations in the sinonasal region, significant association (p<0.01)in the accessory septa within maxillary sinus, was seen among the female participants of the study group. The estimated risk for the CRS in cases and control groups, with OR (odds ratio),were optic nerve protrusion (OR=2.168, 95% CI=1.172-4.010) for the males. Among all the anatomical variations seen in the females, accessory septa within the maxillary sinus were statistically significant (p<0.01)with odds ratio  (OR=2.556, 95% CI =1.309-4.988).

Conclusion

The study findings show marked variations in the sinonasal region, and suggest a cautious preoperative assessment while approaching the cranial regions during surgical interventions.