If you think you are having a medical emergency, call 911.
There is a moment in most emergency visits that decides everything after it: whether the team can look inside you now, or whether you go home with a referral and wait.
That is the whole argument for imaging on site. Not the technology for its own sake — the fact that the answer arrives during the visit rather than next week.
What each type of imaging is actually for
X-ray — fast, low radiation dose, excellent for bone. Suspected fractures, dislocations, some chest and abdominal questions. Often the first look because it is quick and frequently sufficient.
Ultrasound — no radiation at all, works in real time. Gallbladder, kidneys, blood clots in the legs, pregnancy, fluid where it should not be. Safe in pregnancy, which makes it the first choice for many abdominal questions in pregnant patients.
CT (computed tomography) — cross-sectional detail X-ray cannot reach. This is the study that answers the frightening questions: bleeding in the brain, appendicitis, kidney stones, internal injury after trauma, a suspected clot in the lungs. Minutes to perform.
Most visits need one. Some need two in sequence — an X-ray that raises a question, then a CT that settles it.
The part that matters: one visit or two
Without imaging in the building, a patient with severe abdominal pain gets examined, gets a probable diagnosis, and gets sent elsewhere for a scan. That means another trip, another appointment, another wait — and a stretch of time where nobody actually knows whether it is appendicitis.
With imaging on site, the sequence collapses: examined, scanned, read, treated. Same visit.
This is the single biggest practical difference between a freestanding emergency room and an urgent care, and much of why a freestanding ER can often get to an answer in the same visit — there is no queue behind an entire hospital’s inpatient demand. We compare the two in more detail in freestanding ER vs hospital ER.
Both IHCS emergency rooms have CT, X-ray, and a laboratory on site, staffed around the clock. Not available during business hours. On site at 3 AM on a Sunday, because that is when a fair share of emergencies happen.
The honest answer about radiation
People ask, and they deserve a number rather than reassurance.
CT scans do involve ionizing radiation. X-rays involve a smaller amount. Ultrasound and MRI involve none.
Here is the figure, from the FDA. A diagnostic CT delivers an effective dose in the range of 1 to 10 mSv, and at the top of that range the FDA puts the increase in the possibility of fatal cancer at about 1 chance in 2,000. That is a real risk, and it is not zero.
It is also why the FDA’s own position is that used appropriately, the benefits of a CT far exceed the risks: an untreated brain bleed or a ruptured appendix is a far larger and far more immediate danger than the scan that finds it. The FDA adds that detailed CT images may remove the need for exploratory surgery — a risk avoided, not just an image gained.
Children need more care with this, and the FDA says so plainly: pediatric CT warrants special consideration, and the agency notes that about a third of children who had a CT had at least three. Cumulative exposure over years, rather than any single scan, is the thing to keep an eye on — which is why the next point matters.
What a good emergency team does:
- Orders imaging to answer a defined question, not to be thorough for its own sake
- Prefers ultrasound where it will do the job, particularly in children and pregnant patients
- Uses the lowest dose that still produces a diagnostic image
- Asks about pregnancy before any X-ray or CT
Questions you are entitled to ask: What are you looking for? What happens if we do not scan? Is there a test without radiation that would answer this? The FDA encourages this exact conversation, and asks you to mention any past X-rays or CT scans you or your child have had. Any reasonable clinician will welcome all of it.
Who reads the images
A scan is only as useful as its interpretation. Images are read by physicians trained to interpret them, and in an emergency the treating physician often acts on an initial read while a formal report follows.
This occasionally means a call the next day — a radiologist’s full read has added a detail worth acting on. That is the system working, not a mistake.
Before you leave, ask for your imaging results and a copy of the report, and send them to your regular doctor. It prevents the same scan being repeated somewhere else and gives whoever sees you next a real baseline.
Where to find us
- Fountain Hills Emergency Room — 9700 N Saguaro Blvd, Fountain Hills, AZ 85268 · (602) 671-7990 · open 24/7
- El Mirage Emergency Room — 12000 N El Mirage Rd, El Mirage, AZ 85335 · (480) 237-4922 · open 24/7
Emergency physicians on site every hour, with CT, X-ray and a lab in the building, and mobile ultrasound.
Find your nearest 24/7 IHCS emergency room →
Sources
Both links below were opened and read on 13 September 2026. Every radiation figure on this page is the FDA’s; none of it is ours.
- CT dose in mSv, and the cancer-risk estimate at the top of that range. What are the Radiation Risks from CT?, U.S. Food and Drug Administration.
- Benefits against risks, and what to discuss with your physician. Computed Tomography (CT), U.S. Food and Drug Administration.
What each scan is used for, and how we sequence imaging during a visit, describes our own practice rather than either FDA page. Equipment, hours and phone numbers come from IHCS’s own records.
This article is general health information, not medical advice, and it cannot account for your specific situation. Imaging decisions belong to a clinician who has examined you. If you think you are having a medical emergency, call 911.