Does anyone know what this is? (3d reconstruction neck w contrast)

[6tdog6]

So I was looking over my own 3d reconstruction of my neck ct with contrast and see these two odd shapes that are apparently bones? Is this just a glitch? They would be coincidentally on the same side as my symptoms (left). Can anyone please tell me what this could possibly be? Im thinking its just a artifact or something? or is it confusing my artery for a bone? Its very odd, thanks for any insight

[Isaiah_40_31]

Those are definitely interesting finds, @6tdog6 . The longer section looks like a bizarre bony growth off of your first rib. Definitely something worth pointing out to Dr. Costantino when you see him.

[6tdog6]

I’m thinking there’s no way that’s actually a bone, gotta be glitch. Maybe it thinks my artery is a bone? Surely the radiologist would have mentioned these in the report

[6tdog6]

It’s also not on my ct without contrast

[Jules]

I would’ve thought if it was some sort of calcification it would appear on both your CTs, with & without contrast? So quite possibly a glitch?

[6tdog6]

So it’s definitely just a very contrasted vein, so much so that it appears on the bone window. Very odd. Calcified would also appear on bone window on non contrast ct?

[TML]

Best way to find out is to go through the axial view at the level of the clavicle/upper ribs and see if there are any differences when comparing both sides. Probably just contrast reflux especially since it’s not visible in your CT without contrast

[6tdog6]

Yea it definitely is contrast. I just don’t know weather this is still a sign of compression in that area

[MGORNEAU]

put the images into ChatGpt 4.0 and ask what it sees. You can use free version but it allows limited usage during a specified time. It is remarkable skilled at reading imaging, but use a new chat and ask if it sees anything abnormal in your 3D reconstruction of ??? imaging. See what it says if it doesn’t mention the concern, follow up with the annotated image and ask specifically what they are. You could also include the image prior to running it through 3D reconstruction. I typically use the snip tool to take snaps of the slices. It will take 10 at a time. That way it is looking at multiple slices to rule out artifact.

ChatGpt is pretty remarkable at reading imaging but if the chat gets to long or it is a blind request it can get confused and it is awful at annotating images. But it found the lesion at my C1 that Stanford acknowledged, and it identified my bilateral femoral hernias that were just repaired that the radiologist said was a cyst! just remember it can make mistakes and it does get confused if you include to much in the same chat.

[MGORNEAU]

and side note it does not have a measurement tool, it can estimate based on surrounding structures but these are estimates.

[MGORNEAU]

I hope you don’t mind, and if so very sorry I will delete just let me know, but I ran through Chatgpt I have the advanced version and this was the response:

Thanks for sending these. I can see why the member is asking—it’s not always easy to interpret 3D reconstructions, especially in the clavicle and lower neck region where bone, vessels, and cartilage overlap.

Looking at the circled structures:

1. First image (frontal, bone emphasis)

• The circled area shows a bony projection just above the clavicle and near the transverse processes of the lower cervical vertebrae.

• This could represent an elongated anterior tubercle of the transverse process (sometimes called a “cervical rib remnant” if arising from C7).

• Another possibility is part of the first rib or costoclavicular ligament calcification being rendered prominently.

2. Second image (frontal, vessels/muscle overlay)

• With vascular overlay, you can see the subclavian vessels crossing in that same area.

• The circled structure again looks like either a cervical rib fragment or a hypertrophic transverse process impinging close to the thoracic outlet.

• This is the zone implicated in thoracic outlet syndrome when accessory ribs or bony spurs are present.

3. Third image (lateral view)

• The side view supports that it is an extra bony process near C7–T1, projecting downward and forward toward the clavicle/first rib.

• This is most consistent with either:

  • A cervical rib (complete or incomplete), or

  • An elongated C7 transverse process.

---

Bottom line: These circled structures are very likely cervical rib(s) or elongated C7 transverse processes. Both are congenital variants. They can sometimes be incidental, but in people with pain, vascular compression, or nerve issues in that region, they can cause thoracic outlet syndrome–type symptoms.

[TML]

Unlikely to be bones because they would’ve showed on their CT scan that was without contrast as well

[6tdog6]

Yea it’s definitely not bones. It’s that it was filled with contrast so brightly that it thinks it’s bones

[6tdog6]

[MGORNEAU]

I would take the slices from the actual CT prior to 3D reconstruction and put them through Chatgpt to see what it sees. It does clarify that it is not always easy to interpret 3D reconstructions as noted above. I asked if it could be the costoclavicular ligament calcification, see below.
PER AI:

CT vs. 3D Reconstructions

• Standard CT (axial slices, no contrast):
  Calcification is a high-attenuation (bright white) structure. Even a small calcified costoclavicular ligament should show up on the raw CT slices, regardless of contrast, because calcium density is much higher than surrounding soft tissue.
  Contrast is not needed to see calcification—it is usually needed for vascular or soft-tissue differentiation.

• 3D Reconstruction:
  3D volume renderings (VR) or surface-shaded displays often emphasize high-density material (bone, calcification) and suppress soft tissue. This can make calcified ligaments “pop” more clearly than they do in the axial or sagittal slices.
  Small or linear calcifications may be subtle on raw CT slices (especially if windowing isn’t adjusted), but appear more conspicuous once the software reconstructs them into a 3D image.

Why it might appear on 3D but not CT slices

1. Windowing / display issue: On standard bone or soft-tissue windows, the calcification might blend in, but 3D rendering algorithms apply thresholds that highlight high-density voxels.

2. Partial volume averaging: On thin structures, a calcification may not be obvious in a single slice, but the cumulative density is emphasized in reconstruction.

3. Focus of attention: In 3D recon, your eye is naturally drawn to dense struts that shouldn’t be there, while in slice imaging it’s easy to miss unless you’re specifically hunting for it.

Bottom line

Yes—a costoclavicular ligament calcification can look more obvious on a 3D reconstruction and seem “invisible” on routine CT slice review, but technically the calcification is present on the underlying CT dataset. It’s just easier to overlook without tailored windows or multiplanar reformatting.

[MGORNEAU]

I ran the first image you posted through AI, this is the response

Looking at this sagittal CT slice (with crosshairs for orientation):

• Bone structures (vertebrae, sternum, ribs): These appear intact and symmetric.

• Calcifications: There is a bright, focal, high-density area right where the pink and yellow lines intersect, in the region of the costoclavicular ligament / upper chest junction. That is consistent with a small ligamentous or enthesopathic calcification.

• Trachea and airways: The black rounded structure just in front of the spine is the airway (trachea). It looks patent (open).

• Soft tissue: No obvious mass is seen on this single slice.

Interpretation

What stands out as abnormal is the focal calcification near the costoclavicular space (where the clavicle meets the first rib). This is not typical bone—it has the density of calcified soft tissue, and fits with ligament or tendon calcification (costoclavicular ligament calcification or enthesopathy).

It would not require contrast to appear—calcium is bright on CT—but depending on slice thickness and windowing, it may look subtle on 2D slices while showing up more clearly on 3D reconstructions.

Would you like me to compare this to a 3D reconstruction view and mark exactly where that calcification corresponds, so you can see how it “hides” on CT slices but pops on 3D?

[TML]

You’re still missing the fact that the white artifacts are not present in the CT without contrast. A CT that is meant to look at bones. @6tdog6 didn’t grow massive bones off their ribs between their CT without contrast and CT with contrast.

Should be a decently easy area to palpate to feel if there is bone or not I would think @6tdog6

[MGORNEAU]

The statement that “the white artifacts are not present in the CT without contrast” is incorrect. Calcification is not dependent on contrast. Calcium has a much higher attenuation than soft tissue, so it shows up bright on both non-contrast and contrast CT scans.

What can differ is how visible it is:
• On 2D slices, small linear calcifications can be subtle or partially averaged out depending on slice thickness and windowing.
• On 3D reconstruction, the rendering algorithm thresholds for high-density voxels, which makes calcified ligaments “pop” in ways that are easy to overlook in raw slices.

In other words, the calcification is there on the CT dataset — it just may not stand out without the right windowing or reformatting. It’s not “massive bones growing” overnight, it’s ligamentous calcification that reconstruction highlights more clearly.

This matters because the costoclavicular space contains the subclavian vessels and brachial plexus. Dismissing these findings can mislead people who actually do have costoclavicular calcification contributing to thoracic outlet compression symptoms.

[TML]

I think you are confused…

@6tdog6 went and got two separate CTs done. One that involved injecting contrast to see vascular structures - which is the CT scan we are seeing in both the 3D and non-3D models.

They also got a CT where there was no contrast injected, where the vascular structures would not be visible and just the bones would be. In that CT there were no white artifacts - meaning no calcifications of any kind or any bones where there shouldn’t be bones. So the contrast is what’s making it look like bone.

You are relying way too heavily on chatgpt for something that intuitively does not make sense. If they were calcifications/bones then they would show on the CT that lacked contrast because bone always shows. It only showed in the CT with contrast meaning the contrast is the culprit.

[MGORNEAU]

I want to clear up some confusion here because this is important for people trying to get help.

1. Contrast cannot mimic bone.
• Bone/calcification has an attenuation of ~1000 HU.
• Iodinated contrast has an attenuation closer to 200–300 HU in vessels.
• Radiologists distinguish them every single day — contrast does not “turn into” bone or create isolated dense bands in a ligament.

2. Why it looks different across CTs.
• Small calcifications can be missed on thicker slices or with different windowing.
• 3D reconstruction uses density thresholds that enhance bright voxels, so subtle calcifications that blend on 2D slices “pop” on 3D.
• That doesn’t mean they’re artifacts — it means they’re being highlighted.

3. Clinical relevance.
• Costoclavicular calcification is well-documented and can narrow the thoracic outlet, compressing veins/nerves.
• Dismissing these findings as “contrast artifacts” risks misleading people with real compression symptoms.

Bottom line: If it looks like a dense ligament in 3D, it’s because there is high-density tissue there. Contrast doesn’t manufacture “fake bones.” That’s why calcification always deserves a second look, especially in a symptomatic area.