Sleeping without pillows may actually help people with glaucoma protect their vision.A new, preliminary study suggests stacking pillows under the head at night may raise eye pressure to potentially harmful levels.Researchers followed 144 adults with glaucoma, checking their eye pressure every two hours over a full day.The results: When participants laid flat, intraocular pressure was lower. But when their heads were propped up by two pillows, it rose significantly.Blood flow to the eye also dropped with extra elevation — a concern because the optic nerve needs a steady supply of oxygen and nutrients.The researchers say stacked pillows alter neck position, which may compress the jugular vein and interfere with natural fluid drainage from the eye.Younger adults and people with the most common form — primary open-angle glaucoma — were especially affected.The authors stress skipping pillows is not a replacement for glaucoma medication or laser treatment,but avoiding positions that bend the neck could become a low-cost way to help manage eye pressure overnight.Larger studies are now needed to confirm the results.Source: British Journal of OphthalmologyAuthor Affiliations: Zhejiang University, Eye Center of Second Affiliated Hospital, Zhejiang Provincial Clinical Research Center for Eye Diseases, Zhejiang Provincial Engineering Institute on Eye Diseases, Hangzhou Third People’s Hospital, Huanjiang Laboratory, Zhejiang Chinese Medical University .Sign up for our weekly HealthDay newsletter