Dr. Koralla Raja Meghanadh
Sinusitis Diagnosis - How to identify sinusitis?
Updated: Jan 17

An ENT doctor uses the below methods to diagnose sinusitis
diagnostic nasal endoscopy
CT scan of the sinuses - only for chronic sinusitis
MRI is done only if the ENT doctor suspects anything beyond sinusitis, like a complication of sinusitis or something like a tumor.
Diagnostic nasal endoscopy for sinusitis
In the diagnostic nasal endoscopy examination, we can see some polyps. Polyps are grape-like structures that are pale white and semi-translucent. The polyps block the nasal path and drainage path of the sinuses.
These nasal polyps are seen with endoscopy in the early stages of sinusitis, i.e., in grade 1. In grade 4 or later stages of sinusitis, they can be seen with just a headlight.

We might find mucoid discharge, which is like strings of thin gum. We might see yellow pus in the nose's crevices(sinus opening). If we see green color pus, the sinusitis is of long-standing duration and the bacteria involved is Pseudomonas aeruginosa.
CT scan for Sinusitis
When to get a CT scan for sinuses?
CT scan is only done in chronic sinusitis or "acute on chronic" sinusitis. In acute sinusitis, the doctor stops at diagnostic nasal endoscopy, and a doctor first tries out medication. An ENT doctor will prescribe a CT scan if the symptoms don't die completely after an entire course of medication. If there are complications or other underlying problems of concern, then only it is prescribed for acute sinusitis patients.
What to expect from a CT scan of the sinuses?
In a CT scan, we look for two things.
1. Anatomical anomalies
Deviations in the sinus drainage path and opening that are responsible for the stagnation of the fluids can be identified in a CT scan.
2. Contents of the sinuses
Air filled in sinuses is indicated by black color.
If the sinuses have pus, then it will be greying color. If there is a fluid level, the sinus has fluid.
For fungal sinusitis, we can see a gray shadow with white color shadows inside. These fungi live in harmony with other bacteria and fungi, protecting each other. They develop colonies whenever fungus is in the sinuses for a long time. They construct houses with heavy metals (iron, molybdenum, lead, etc.), forming towns with distinguished nutrition and drainage systems. In short, a community of organisms lives inside the sinuses.
When fungal sinusitis is confirmed from the CT scan, antifungal treatment is added accordingly. These fungi cause an allergic reaction in some patients leading to further swelling of the nasal mucosa. This causes more blockage and worsening of the symptoms.