Dental X-rays Linked to Brain Tumors

In a study spanning over decades, researchers have found an association between dental x-rays and increased risk of a non-malignant type of brain tumor called meningioma.

Of the four types of dental x-rays, only the full-mouth series was associated with this increased risk. More specifically, the risk was elevated with the aggregate number of full-mouth series in 10-year periods from approximately 15–40 years before diagnosis, with significant elevations in the 10-year periods beginning 22–30 years before diagnosis. The risks in these analyses were even greater when only women were considered.

One needs to be aware that radiation exposure from full-mouth series was much greater in the past than it is now and as such, this risk may be nominal (though not zero) with current dental x-ray technology.

However, it also should be a reminder that x-rays should not be routinely performed unless there is a very good reason to obtain especially in children who are more susceptible to radiation injury... and that applies to not only x-rays, but any kind of testing involving ionizing radiation including CT scans.

Some x-rays should NEVER be performed including sinus x-rays for sinus problems given a nearly 50% error rate in diagnosing the presence OR absence of sinus problems.

X-rays for nasal fractures is not recommended given x-rays rarely change how such fractures are managed.

Soft-tissue lateral x-rays to look for large adenoids should also be discouraged as nasal endoscopy can provide similar if not better information without any radiation exposure.

To know what the cancer risk is with different types of x-rays, check out this website!

Source:
Dental X-rays and the risk of intracranial meningioma. Cancer. Volume 100, Issue 5, pages 1026–1034, 1 March 2004

Avoidable Pediatric Radiation Exposure

Children and teens often get diagnostic tests that expose them to radiation, increasing the risk of cancer later in life. Over just a 3 year span, 42.5% of kids got some form of ionizing radiation from a diagnostic medical procedure whether it be a chest x-ray, CT scan, dental scan, etc. Click here to calculate the cumulative risk of cancer with each type of test.

From an ENT standpoint, common diagnostic tests that expose patients to radiation include CT scans of the head, facial x-rays, and neck x-rays.

Why would kids get such scans done?

CT scans are often performed to evaluate for sinusitis as well as to figure out what is causing chronic headaches. Neck x-rays are often done to evaluate for adenoid hypertrophy while facial x-rays are done after facial trauma to look for a nasal fracture.

It is my personal bias to avoid such diagnostics tests if at all possible, ESPECIALLY because there are alternative options.

Nasal endoscopy can be performed to evaluate for sinusitis as well as adenoid hypertrophy thereby making unnecessary the need for neck x-rays as well as CT scans. X-rays to evaluate sinusitis is NEVER indicated as it is wrong 50% of the time (click here for more info on this).

Nasal fractures are easily appreciated on exam thereby making unnecessary facial x-rays. In cases of trauma, an x-ray can be considered from a purely medico-legal documentation standpoint, but is not really necessary from a medical standpoint. Read more here why.

Read a story about this in Reuters.

Are Doctors Required to Obtain Patient Permission For Posting Non-Identifiable X-Rays, CT Scans, Etc Online?

The blunt answer is no... as long as there is no way the patient can be identified by looking at the image. (in other words, anonymous).

Dr. Ves Dimov at CasesBlog has written a very good article regarding this very question and the guidelines used to determine whether patient permission is required or not.

Read his blog article here.