X-ray and CT Scan for Diagnosing Sinusitis

This article was first published at SinusDoctor by Dr.G V K Chaitanya Rao, a member of American Rhinologic Society (ARS) and European Rhinologic Society (ERS), and has 10+ years of experience in the field of ENT.

In this article: X-Ray & CT Scan for diagnosing sinusitis, X-Ray Limitations, CT Scan Advantages.

X-Ray and CT Scan in diagnosing Sinusitis

X-ray and CT Scan are imaging techniques used to visualize the details of your sinuses. Though both use radio waves, the amount of information provided by a CT scan is way more than what an X-ray provides. The difference is as significant as a 2D photograph vs a 3D model.

It is also important to understand this difference as there is some misinformation about why a CT scan is required for simple symptoms such as nasal congestion! Hope this article helps you appreciate how CT scan can be a useful tool for inaccurate diagnosis and thereby effective treatment.

X-ray and CT scan are 70 years apart. It might not sound like a long period, but having in mind the pace of technological advancements, saying that those two are 70 light years apart from each other probably describes the difference better.

Both methods use X-rays to generate an image. However, the amount of info the X-ray provides is just a fraction of that provided by a CT scan. For accurate diagnosis and clinical decision making in patients with Sinusitis, it is crucial to acquire as much information as possible. And everything is important! For example, a small polyp of just a few millimeters in diameter can entirely change the treatment plan from medical therapy to surgical removal.

Limitations of X-ray

• Conventional radiography doesn’t pick up everything, Due to their anatomical position and technical limitations of the method, sphenoid, and ethmoid sinuses are not visible on plain X-ray
• Limited diagnostic value

The other two pairs – frontal and maxillary sinuses – are visible. However, the diagnostic value of conventional radiography when compared to CT scan is significantly smaller. Research shows that only one of many features of rhinosinusitis (fluid level) is reliable enough for diagnosis confirmation using a plain film. Other signs have a lower diagnostic value. 

The other two pairs – frontal and maxillary sinuses – are visible. However, the diagnostic value of conventional radiography when compared to CT scan is significantly smaller. Research shows that only one of many features of rhinosinusitis (fluid level) is reliable enough for diagnosis confirmation using a plain film. Other signs have a lower diagnostic value.

• Soft tissues are almost invisible on plain film

Radiologists and ENT specialists, when assessing patients with rhinosinusitis are more interested in soft tissue changes than observing bone structures (because they are almost always intact). The focus of their interest is a weak spot of X-ray – soft tissues are almost impossible to visualize (unless there is a thick layer of liquid or cells, conventional radiography won’t pick it up).

Advantages of CT Scan in diagnosing Sinusitis

• CT scan is the gold standard

Computed Tomography (CT Scan) holds a reputation of radiographic gold standard for the diagnosis of various forms of rhinosinusitis. Being a gold standard in medicine means being the most reliable and accurate choice of all available modalities. With just a few rare exceptions it is a better choice for diagnosis even compared with Magnetic Resonance Imaging (MRI).

• CT scan picks up the finest changes in and around sinuses

Another essential question of every patient assessment doctor needs to answer is Why did this episode of rhinosinusitis happen? Most often, the canal that connects a sinus with a nasal cavity is blocked because of swelling caused by the flu, common cold, or allergy but sometimes, the obstruction may be caused by a tumor or a polyp that’s benign at the time, but if it goes unnoticed may turn into malignant in the coming years.

Timely diagnosis is what makes the difference between life and death in such cases. The CT scan generates a perfectly detailed picture of not only bony structures but soft tissues inside those sinuses as well, up to the smallest detail!

To sum things up, the benefits of undergoing a CT scan outweigh the risks! In the past few decades, thanks to technological advancements in radiology the dose of radiation a patient receives during CT scanning is significantly lower than it used to be. The benefits of the procedure are far ahead of risks, and the only limiting factor is its price – the technology is not available in all parts of the world.

More information about diagnosing sinusitis – https://www.healthline.com/health/sinus-x-ray#purpose

If you are looking for an X-ray and CT Scan for diagnosing sinusitis, Consult our best sinus doctor in India Dr.GVK Chaitanya Rao at Sinus Doctor.