Prevalence of Incidental Sinonasal Diseases on Brain Imaging by Computed Tomography Scan

Abstract

Objective: The purpose of this study was to investigate the prevalence of incidental sinonasal
diseases on CT scan in Pakistani population presenting with neurological signs and symptoms for
brain imaging.
Material & Methods: This cross sectional study was conducted in Department of Radiology,
Services Institute of Medical Sciences/ Services Hospital, Lahore, between August 2009 and
June 2010. All the cases undergoing CT head referred by physicians and neurophysicians
presenting with neurological symptoms and signs besides exclusion of the cases of head trauma
were included. The study population consisted of 507 patients, including 311 men and 196
women, who were 2-75 years old (mean age, 42 years). Frontal, ethmoid, sphenoid, left and right
maxillary sinuses were separately evaluated. The pathological processes included were mucosal
thickening, opacification, air-fluid level, retention cysts and polyps.
Results: Out of 507, there were 199 patients (39.25%) in whom sinus pathology was
documented. There were no significant gender differences amongst the study population. Most of
the patients were adults; pediatric age group consisted 11%. The incidental sinonasal disease
was more common in the patients above 30 years of age, with slight predilection toward females
(56%). Mucosal thickening was the most common pathology (71.8%); categorization including
normal (no mucosal thickening), mucosal thickness of 1 mm (34.6%), 2 mm (24.6%), 3 mm
(27.7%), and 4 mm or above (13.1%) was done accordingly. Other abnormalities including sinus
opacification (14%), air-fluid level (5.0%), retention cyst (5.5%) and polyp (3.5%) were found
uncommon.
Conclusion: The high prevalence of sinonasal disease in general population emphasizes the
necessity of clinical correlation, if picked incidentally on cross-sectional brain imaging. Subtle
mucosal thickening, in particular to ethmoidal air cells, is a normal variant, most likely due to the
physiologic nasal cycle. Incidental findings of paranasal sinus disease without clinical signs and
symptoms do not define a diagnosis of sinusitis or a sinonasal disease; adequate clinical
information is mandatory prior to starting the treatment. The possible reason of high prevalence of
sinonasal disease in Pakistani population could be dust allergy and pollution besides respiratory
tract infections and smoking. Future studies are recommended to a larger population to evaluate
the significance of these incidental findings