Sinusitis Diagnosis - How to identify sinusitis?

Dr. K. R. Meghanadh

An ENT doctor uses the below methods to diagnose sinusitis

1. diagnostic nasal endoscopy

2. 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.

A clear visual of nasal polyps in the left nostril of the patient i.e. on the right side of the image - in chronic patient

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.

Dr. K. R. Meghanadh

FAQs

How is acute sinusitis diagnosed?

Acute sinusitis is diagnosed using nasal endoscopy. As it is the early stage of sinusitis, doctors usually don't use a CT scan to diagnose. However, suppose complications arise or the condition doesn't respond to medication as per their expectations. In that case, a CT scan may be recommended by doctors to gain a more detailed understanding of the infection.

Why would an ENT order a CT scan of sinuses?

Usually, an ENT doctor orders a CT scan to see detailed images of your sinuses. In a CT scan, we can see if there are any anatomical anomalies in the sinus drainage pathway and the contents of the sinuses, like if they are filled with air, pus, fluids, or fungus. So, with the help of a CT scan, doctors can determine which sinuses are affected and how severe the infection is.