A 30 year old man presented with 6 month history of nasal discharge, facial pain and fever. On antibiotic therapy, fever subsided. After 1 month again he had symptoms of mucopurulent discharge from the middle meatus and the mucosa of the meatus appeared congested and oedematous. Next best investigation would be

NCCT (Non-Contrast CT) is the gold standard imaging modality for evaluating chronic sinusitis and recurrent nasal infections. It provides detailed visualization of the bony walls of the paranasal sinuses and identifies mucosal thickening, air-fluid levels, or osteomeatal complex obstruction. Plain X-rays are largely obsolete for this purpose. MRI of the brain is unnecessary as there is no intracranial pathology suggested. Inferior meatus puncture is an outdated diagnostic procedure rarely used today.