Are There Weight Limits for MRI, CT, or X-Ray Scans?

Every medical imaging machine has its limits. In order to complete a scan, radiologists and their patients must meet a few simple conditions. Patients must be able to lie on the imaging table. They must fit inside the MRI tube.

Most patients who find it difficult to enter a standard MRI machine can opt to use an open MRI scanner, which has the added benefit of relieving claustrophobia. Still, for the 6.3 percent of Americans who have a BMI that’s greater than 40, medical imaging may pose special challenges.

So how do you know if you need to ask for an open MRI, or if your doctor should consider alternative imaging modalities due to incompatibility with machine limits? Start by asking if there’s a weight limit on the imaging machines at the facility of your choice.

Here’s what you need to know about medical imaging for patients on the higher end of the BMI spectrum.

1. Ultrasound might not be a viable option for larger bodies.

The presence of fatty tissue obscures ultrasound images to the point where doctors may not order this imaging procedure. The sound frequencies used to generate images in an ultrasound lose intensity as they travel through fatty tissue. This can affect image resolution, or even prevent imaging at all. Ask your doctor if an ultrasound is right for you.

2. X-ray, MRI, and CT tables have weight limits.

Imaging tables and scanners have varying capacities, but unless a procedure can be completed with the patient standing (such as certain X-rays and ultrasounds), there will be limits.

MRI machines typically support weights of up to around 400 pounds. Some scanners max out at closer to 300 pounds. CT scanners tend to have weight limits that hover around 450 pounds. X-ray tables, used in procedures that require the patient to lie prone, have a wide variety of weight limits. The tables used at Yale Health are rated for 300 pounds, while Massachusetts General Hospital lists their X-ray weight limit at 480 pounds.

Imaging facilities use different equipment, and they might not share the same weight limits. If you’re worried about your weight as you prepare for a diagnostic procedure, talk to the staff at your imaging facility. They’ll be able to guide you through the scans your doctor orders.

3. A patient with a BMI over 40 may not fit into closed-bore CT or MRI scanners.

Unfortunately, weight limits aren’t the only restrictions found in closed-bore imaging machines. Many MRI tubes have diameters of around 25 feet. CT scanners aren’t much bigger.

This brings us to our next point.

4. Open MRI scanners are a great option for patients with larger bodies.

Open MRI machines require patients to lie beneath a ring-like scanner, without fully enclosing their bodies. This creates far greater clearance than a closed-bore MRI. Ask your service provider if an open MRI is an option.

If you’re concerned about weight limits or enclosed spaces involved in a medical imaging procedure, talk to your doctor. Your health care team will be able to plan a diagnostic procedure that provides the information they need.

Many patients feel better when they contact their imaging facility to discuss their case before arriving for the appointment. The friendly staff at will be happy to address any concerns with compassion, respect, and understanding.

Call at 888-322-7785 to find out more about open MRI options and other ways to comfortably get the imaging care you need at a price you can afford.


Are there weight limits for having an X-ray, MRI, CT scan, or ultrasound at Yale Health?YaleHealth. Yale University, n.d. Web. 15 June 2017.

Miller, Janet. “Imaging and Obese Patients.MassGeneral. Massachusetts General Hospital Department of Radiology, July 2005. Web. 15 June 2017.

Overweight and Obesity Statistics.NIDDK. National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Oc. 2012. Web. 15 June 2017.