CT PNS Scan in Delhi 2026 — Sinus CT Cost & Report

Your ENT doctor has written “CT PNS” on a prescription and you are wondering what it is, why an X-ray will not do, and what the report will tell you. This guide answers all of that in plain language — and explains the parts of a sinus CT report that actually change your treatment.

A CT PNS scan is one of the most commonly advised scans in ENT practice, and also one of the most commonly misunderstood. Patients often arrive expecting it to “confirm sinusitis”. In reality, sinusitis is usually diagnosed from your symptoms and an endoscopy. The CT does something different and more useful: it maps the shape of your sinuses, shows exactly which drainage pathways are blocked, and tells a surgeon what the anatomy looks like before any instrument goes in.

What a CT PNS scan actually is

PNS stands for paranasal sinuses — the four paired air-filled spaces inside the bones of your face and skull: the maxillary sinuses (in the cheeks), the ethmoid sinuses (between the eyes), the frontal sinuses (in the forehead) and the sphenoid sinuses (deep behind the nose).

A CT PNS scan is a thin-section computed tomography study of that whole region. The scanner takes a continuous spiral of very thin slices — typically under a millimetre — through your face, and a computer then reconstructs that data in three planes: axial (looking up from below), coronal (looking from the front) and sagittal (looking from the side). The coronal plane is the one ENT surgeons study most closely, because it shows the drainage channels in the orientation they will actually be working in.

It is almost always done without contrast. Bone and air have naturally enormous contrast with each other on CT, so no injection is needed to see sinus anatomy clearly. Contrast is reserved for specific situations, covered further down this page.

If you want background on how CT works in general, our complete guide to CT scanning covers the technology and safety in more detail.

When an ENT doctor orders a CT PNS

A sinus CT is not a first-line test for a blocked nose. It is ordered when a decision depends on anatomy. The common reasons are:

Chronic rhinosinusitis that has not responded to medical treatment. If you have had twelve weeks or more of nasal blockage, discharge, facial pressure or reduced smell, and a proper course of medication has not fixed it, the CT shows whether there is a structural reason.
Planning endoscopic sinus surgery (FESS). This is the single biggest reason. No responsible surgeon operates on sinuses without a current CT.
Suspected nasal polyps or polyposis. The CT shows how extensive the polyps are and which sinuses they fill.
Suspected fungal sinusitis. Dense material inside a sinus, sometimes with specks of calcification, raises this possibility.
Recurrent acute sinusitis — several distinct episodes in a year.
Complications of sinusitis — swelling around the eye, visual change, severe headache or any sign that infection has spread beyond the sinus.
Facial trauma, where sinus wall and orbital floor fractures need to be excluded.
A suspected sinonasal mass, persistent one-sided blockage, or repeated nosebleeds from one side.
Loss of smell (anosmia or hyposmia) that has no obvious cause.
Unexplained facial pain where the sinuses need to be ruled in or out.

Notice the pattern: in almost every case the CT is answering “what is the structure?” rather than “is there inflammation?”.

What a CT shows that an X-ray cannot

For decades the standard sinus test was a plain X-ray — the Water’s view. It is still occasionally done, and our digital X-ray guide explains the technique. But for sinuses it has been largely superseded, for good reasons.

An X-ray compresses the entire depth of your face into one flat image. The maxillary sinuses are reasonably visible on it; the ethmoid air cells, which are the most surgically important region, are effectively invisible. An X-ray cannot show the osteomeatal complex — the narrow common drainage corridor where most sinus disease actually begins. It cannot grade how full a sinus is. It cannot show the position of the skull base or the eye socket wall relative to the surgical route. And it produces a fair number of false positives, because overlapping soft tissue of the cheek can mimic a cloudy sinus.

A CT resolves every one of those limitations. That is why the prescription says CT and not X-ray.

The anatomy your report will name, and why each part matters

Sinus CT reports are dense with anatomical terms. Here is what the important ones mean.

The osteomeatal complex (OMC)

Also called the osteomeatal unit. This is not a sinus — it is the shared narrow drainage channel through which the maxillary, anterior ethmoid and frontal sinuses all empty into the nose. If the OMC is blocked, three sinuses silt up behind it. Most functional sinus surgery is aimed precisely at reopening this corridor, which is why a report will almost always comment on whether the OMC is patent or obstructed on each side.

Deviated nasal septum (DNS) and nasal spur

The septum is the partition between the two nostrils. A deviation to one side is extremely common and often harmless. It becomes relevant when it is severe enough to obstruct airflow, or when a bony spur presses against the lateral nasal wall and interferes with drainage. The report will usually state which side the septum deviates to and whether a spur is present.

Concha bullosa

An air-filled expansion of the middle turbinate. Common, usually incidental, occasionally large enough to crowd the drainage pathway.

Haller cells (infraorbital ethmoid cells)

Small air cells sitting along the floor of the eye socket, above the maxillary sinus opening. When prominent, they narrow the maxillary drainage route — and during surgery they sit uncomfortably close to the orbit, so the surgeon wants to know about them in advance.

Onodi cells (sphenoethmoidal cells)

Posterior ethmoid air cells that extend backwards over the sphenoid sinus. This matters because the optic nerve may run through or alongside an Onodi cell, sometimes with very thin bone covering it. A surgeon who does not know an Onodi cell is present is operating near the optic nerve without realising it. Reporting these is not an academic exercise — it is a safety issue.

Agger nasi cell and the frontal recess

Air cells around the entrance to the frontal sinus drainage pathway. Their configuration decides how difficult frontal sinus surgery will be.

Keros classification of the olfactory fossa

This grades how deeply the olfactory fossa — the groove in the skull base where the smell nerves pass — hangs down between the ethmoid sinuses. Keros described three types by the depth of the lateral lamella of the cribriform plate: shallow (Type I), intermediate (Type II) and deep (Type III). A deep Type III fossa means the skull base dips low into the surgical field with a long, thin lamella of bone beside it, so the risk of entering the cranial cavity and causing a cerebrospinal fluid leak is higher. A good report states the Keros type on each side.

If you are reading a report that also mentions the ear or mastoid, that is a different study — see our guide to the HRCT temporal bone scan.

How sinus disease is scored: the Lund-Mackay system

Radiologists need a consistent way to describe how much of your sinus system is opacified, so that a second scan months later can be compared meaningfully. The most widely used method is the Lund-Mackay score.

Each sinus group on each side — maxillary, anterior ethmoid, posterior ethmoid, frontal and sphenoid — is given a score of 0 if it is clear, 1 if it is partially opacified, and 2 if it is completely opacified. The osteomeatal complex is scored differently: 0 if open, 2 if obstructed. That gives a maximum of 12 per side and 24 in total.

A score of 0 means a radiologically clear sinus system. Low single-digit scores are common and often incidental. High scores, particularly with an obstructed OMC on both sides, support a diagnosis of significant chronic sinus disease. The score does not by itself decide whether you need surgery — your symptoms and endoscopy matter at least as much — but it gives your ENT surgeon an objective number to work with and to track.

Before FESS surgery: the three things your surgeon is looking for

If surgery is on the table, your surgeon is reading the CT for three things, in this order:

Where is the disease? Which sinuses are involved, how completely, and is the OMC blocked. This defines the extent of surgery needed.
Where are the danger zones? The skull base above (Keros type, any bony defect), the orbit laterally (how thin is the lamina papyracea, is there any dehiscence), the optic nerve and carotid artery posteriorly (Onodi cells, sphenoid sinus wall anatomy). These define where not to go.
What anatomical variants will change the approach? Haller cells, concha bullosa, septal deviation, an uncinate process attached in an unusual position, a hypoplastic or asymmetric sinus.

This is why a CT from two years ago is rarely acceptable for surgical planning. Both disease and post-surgical anatomy change.

Plain CT or contrast CT — how that is decided

The default CT PNS is plain, with no injection. Intravenous contrast is added only when soft tissue needs to be characterised rather than simply located. The usual triggers are:

A suspected tumour or mass in the nose or sinuses.
A suspected abscess, or infection that appears to have spread into the eye socket or towards the brain.
A vascular lesion, or heavy recurrent bleeding from one side.

In those situations an MRI is often requested alongside or instead, because MRI distinguishes different kinds of soft tissue far better than CT does. Our guides to CECT brain imaging and contrast-enhanced MRI explain how contrast studies are run and what the kidney-function precautions are.

How to prepare for a CT PNS scan

For a plain CT PNS, preparation is minimal:

No fasting is needed. Eat and drink normally.
Take your regular medicines as usual.
Remove metal from the head and neck — spectacles, earrings, nose pins, hair clips, removable dentures and any piercing. Metal creates streak artefacts that can obscure anatomy.
Carry your prescription and any previous scans or reports. A prior CT is genuinely valuable for comparison, especially after earlier surgery.
Tell the staff if you are pregnant or might be, before the scan — not after.
Mention previous sinus surgery. The radiologist will report post-operative anatomy differently, and will specifically look for recurrence patterns and any skull base defect.

If contrast has been advised, you may be asked to fast for a few hours and to bring a recent kidney function test. Our health checkup page explains what a basic renal panel involves.

What actually happens during the scan

You lie on your back on the CT table with your head resting in a padded support and a light strap to keep it still. The table moves slowly into the open ring of the scanner. Unlike MRI, a CT scanner is a short ring, not a tunnel — most people who find MRI claustrophobic have no difficulty with CT. If closed spaces are a real problem for you for other scans, our open MRI page explains the alternative.

You will be asked to stay still and to breathe quietly. Some centres ask you not to swallow during the acquisition. The actual scanning takes only a few seconds; the whole appointment, including positioning and checking the images, is usually about ten to fifteen minutes. There is no pain and no sensation at all from the X-rays.

Afterwards you can leave immediately and resume everything normally. There are no after-effects from a plain CT.

Radiation dose, and who should think twice

CT uses X-rays, so there is a radiation dose, and it is reasonable to ask about it. Two things are worth knowing.

First, a sinus CT is one of the lower-dose CT examinations. Because bone and air contrast so strongly, diagnostic images can be produced with far less radiation than a chest or abdominal CT needs. Modern low-dose sinus protocols, with iterative reconstruction and tube-current modulation, keep the effective dose well under one millisievert — a fraction of what a routine CT of the head or abdomen delivers. The exact figure depends on the scanner, the protocol and the area covered, so ask your centre what protocol they use.

Second, dose should still be justified rather than ignored. The guiding principle is ALARA — as low as reasonably achievable. Practically, that means:

Pregnancy: tell the team. A sinus CT is far from the uterus and the direct fetal dose is extremely small, but the scan should still be deferred unless it is genuinely needed now, and the decision should be made with your doctor.
Children and teenagers: growing tissue is more radiosensitive, so paediatric low-dose protocols should be used and the indication should be clear. Repeated sinus CTs in a child deserve a conversation.
Repeated scans: if you have had a sinus CT recently, bring it. A second scan within a short period is sometimes necessary but should be a deliberate choice.

CT PNS versus MRI of the sinuses

These are complementary, not interchangeable.

CT is better for bone, air and surgical mapping. It shows the bony walls, the drainage channels, the skull base, anatomical variants and the precise geometry a surgeon needs. It is faster, cheaper and more widely available. For routine chronic sinusitis and for FESS planning, CT is the correct study.

MRI is better for soft tissue. It distinguishes a tumour from retained secretions, characterises fungal material, and shows spread into the orbit, the cavernous sinus or the brain far more reliably. It uses no ionising radiation. But it shows bone poorly, takes much longer, and is not what a surgeon wants for anatomical mapping.

So: suspected inflammatory sinus disease or pre-surgical planning, CT. Suspected mass, fungal invasion or intracranial or orbital extension, MRI — often in addition to CT. Our MRI versus CT comparison and MRI brain page go further into this.

Reading your own report: a plain-English glossary

Mucosal thickening — the lining of the sinus is swollen. Mild thickening is very common and often means nothing on its own.
Opacification — the sinus is filled with something other than air: fluid, thickened lining, polyps or secretions. “Complete opacification” means entirely filled.
Air-fluid level — a flat line of fluid with air above it, usually indicating acute infection or recent fluid accumulation.
Patent — open. “OMC patent bilaterally” is good news.
Polypoidal mucosal thickening — the swollen lining has a lumpy, polyp-like shape.
Hypoplastic sinus — a sinus that is naturally small or underdeveloped. A normal variant, but important for the surgeon.
Lamina papyracea — the paper-thin bone between the ethmoid sinus and the eye socket. The report comments on it because it is the wall a surgeon must not breach.
Dehiscence — a gap or defect in a bony wall.
Mucocele / mucous retention cyst — a sinus or small cyst filled with trapped mucus.
Antrochoanal polyp — a polyp arising in the maxillary sinus and extending backwards into the nose.

One important caution: incidental sinus findings are extremely common. Mild mucosal thickening turns up on a large proportion of head CTs done for completely unrelated reasons, in people with no sinus symptoms whatsoever. A CT finding only matters when it matches your symptoms. Do not treat a report in isolation — take it back to the doctor who ordered it.

What a CT PNS scan costs in Delhi

The price of a CT PNS in Delhi depends on several real variables: whether the study is plain or contrast-enhanced, the scanner and protocol used, whether thin-section reconstructions in all three planes are included, whether a radiologist’s formal report and a digital copy are included, and whether you need it urgently or outside normal hours.

Because of that, we do not publish a fixed figure on this page that might be out of date by the time you read it. The fastest way to get an accurate, all-inclusive number is to send us a photo of your prescription on WhatsApp. You will get today’s actual price for exactly what your doctor has asked for — plain or contrast, with the report included — along with the next available slot, before you travel.

Send your prescription on WhatsApp for today’s CT PNS price →

For a broader view of CT pricing across studies, see our CT scan cost in Delhi page. If your ENT doctor has also advised dental imaging, the OPG dental X-ray page covers that, and sialography covers salivary gland studies.

Getting a CT PNS scan in West Delhi

At Edge Imaging & Diagnostics, a NABH-accredited diagnostic centre in Paschim Vihar, West Delhi, a CT PNS is done as a thin-section study with axial, coronal and sagittal reconstructions as standard, reported by a radiologist rather than returned as images alone. Where the clinical question allows it, a low-dose sinus protocol is used.

Practical points that matter when you are booking:

Pathology, digital X-ray, ultrasound, CT and MRI are all in the same building, so if your ENT doctor has asked for more than one test you are not travelling between centres.
We are open on Sundays — see our Sunday diagnostic centre page.
We are CGHS and DGHS empanelled.
Patients come to us from Paschim Vihar, Rajouri Garden, Tagore Garden, Punjabi Bagh, Janakpuri, Tilak Nagar, Vikas Puri, Nangloi and Raghubir Nagar. See our West Delhi diagnostic centre and Rajouri Garden pages.
If your symptoms involve breathing as well as the nose — allergic rhinitis overlapping with asthma is common — your doctor may add a pulmonary function test.

Frequently asked questions

Is a CT PNS scan painful?

No. There is no needle for a plain CT PNS and no sensation from the X-rays. You simply lie still for a few seconds. If contrast has been advised, there is one cannula in the arm and many people feel a brief warm flush when the injection runs.

How long does a CT PNS scan take?

The scan itself takes only seconds. Allow about ten to fifteen minutes in the room for positioning and image checking. If contrast is involved, allow longer.

Do I need to fast before a CT PNS?

Not for a plain study — eat and drink as normal. If your doctor has specifically asked for a contrast-enhanced scan, you may be asked to fast for a few hours; the centre will tell you when you book.

Is a CT PNS scan done with or without contrast?

Almost always without. Bone and air give natural contrast on CT, so no injection is needed for sinus anatomy. Contrast is added when a mass, an abscess or spread of infection beyond the sinus is suspected.

How much radiation does a sinus CT involve?

Less than most other CT examinations. With a modern low-dose sinus protocol the effective dose is kept well under one millisievert, considerably lower than a routine head or abdominal CT. The exact figure depends on the scanner and protocol, so ask your centre.

Can I have a CT PNS scan during pregnancy?

Tell the staff before the scan. The sinuses are far from the uterus and direct fetal exposure is very small, but a sinus CT in pregnancy should still only be done when it is genuinely needed, and that decision belongs with your treating doctor. An MRI may be offered instead.

What does a Lund-Mackay score of, say, 8 mean?

It means that across the ten sinus groups and the two drainage complexes, the total opacification adds up to 8 out of a possible 24. It indicates moderate radiological disease. On its own it does not decide treatment — your symptoms and your endoscopy findings weigh at least as heavily. Discuss the number with your ENT doctor.

My report says mild mucosal thickening. Do I have sinusitis?

Not necessarily. Mild mucosal thickening is a very common incidental finding, including in people with no nasal symptoms at all. A CT finding is meaningful only when it matches your clinical picture.

Will the CT tell me whether I need sinus surgery?

It is one of the three inputs, not the decision itself. Surgery is usually considered when significant symptoms persist despite adequate medical treatment, endoscopy confirms disease, and the CT shows a structural problem that surgery can actually correct. A high score with no symptoms is not an indication to operate.

Why does my report mention Onodi cells and Keros type? I only have a blocked nose.

Because those details are safety information for a surgeon. An Onodi cell can carry the optic nerve into the surgical field, and a deep Keros type III olfactory fossa brings the skull base lower with thinner bone beside it. Reporting them in advance is how operative complications are avoided. Their presence is not itself a disease.

Is a CT PNS the same as an HRCT of the sinuses?

In practice the terms are used interchangeably. Both mean a thin-section, high-resolution CT of the paranasal sinuses with multiplanar reconstructions. A CT PNS done properly is already high-resolution.

Can an X-ray of the sinuses replace a CT?

Not for any decision that depends on anatomy. An X-ray cannot show the ethmoid air cells or the osteomeatal complex, cannot grade opacification reliably, and produces false positives from overlapping soft tissue. No surgeon will plan FESS from an X-ray.

I had sinus surgery three years ago and symptoms are back. Do I need a fresh CT?

Almost certainly yes. Surgery permanently changes the anatomy, so an old pre-operative scan no longer reflects what is there. A fresh CT shows the post-operative cavity, where disease has recurred, and whether any bony wall is now thin or absent. Bring the old scan too — the comparison is genuinely useful.

How soon will I get the report?

Ask when you book. At our centre a routine CT PNS report is normally available the same day, and urgent studies are reported faster. Carry a digital copy to your ENT appointment, not just the printed report — your surgeon will want to scroll through the images.

Medically reviewed by Dr. Nishant Thapar, Consultant Radiologist and Founder, Edge Imaging & Diagnostics, West Delhi. Last reviewed: October 2026.

Disclaimer: This article is for general patient information and does not replace a consultation. Scan findings must always be interpreted together with your symptoms and examination by the doctor treating you. Do not start, stop or change any treatment on the basis of this page. The anatomical and scoring descriptions here reflect standard radiological practice; individual reports vary.