The close quarters of an MRI machine are unsettling, but for a percentage of the population, gripping claustrophobia makes completing a scan nearly impossible, the Washington Post reported this week.

“There’s a percentage of the population that flat-out will not be able to get an MRI, just because the claustrophobia is so intense,” Mike Skok, a senior executive at an MRI manufacturing company, told the Post. “So those folks just can’t get scanned.”

It’s not just the restricted space, either. Up to 13 percent of patients have reported having a panic attack in an MRI machine, which can be spurred by both claustrophobia and the banging noise created by the MRI’s pulsating magnetic coils.

“Open” MRIs are on the market, the Post reported, but are criticized for weaker image quality and lower magnetic field strength. Traditional, closed MRIs operate at four to five times the strength of their open counterparts.

Sian L. Spurney, an internist, told the Post that patients who struggle to stay still on the gurney for as long as an hour and struggle with claustrophobia may feel like they’re being buried alive.

“It’s hard to predict who is going to have a bad experience,” Spurney said. “It’s embarrassing for patients, and it often jams up the schedule for other MRIs.”

Read the Post’s full story here: