Mask Squeeze

December 14th, 2015

I am a recently-certified diver and have just completed my first offshore dive trip. I had what looked like a bright red patch of blood over the white of my eye when I looked in the rear-view mirror on the way home. When I asked my instructor about it, he said it was probably due to mask squeeze.

How does mask squeeze cause me to get a blood spot on my eye, and can this be a serious condition? What is the treatment for mask squeeze? Should I be concerned if this happens again?

_{While your concern is perfectly understandable, mask squeeze is usually not serious.}

^{What is mask squeeze?}
_{Like the air spaces in your sinuses and ears, you must also equalize the air space in your mask as you descend. When you descend, failure to equalize, or add air to the air space in the mask, by exhaling through your nose can create unequal pressure between the mask air space and the vascular pressure within the blood vessels of the face. This can result in various degrees of facial barotrauma, or injury to the soft tissues of your face contained within the mask. Imagine your face in a suction cup. The soft tissues beneath the mask, and especially around the eye, swell (periorbital edema) and discolor, such as redness or bruising (ecchymosis).

What treatment do I need?

Unless you are experiencing eye pain or visual problems, there is no treatment for facial barotrauma except time. Because it is a bruise, your body will eventually reabsorb the effect of your mask squeeze. Your physician or an eye specialist should address eye pain or visual disturbances such as blurred vision or loss of part of the visual field immediately. These symptoms would be extremely rare in mask squeeze, however. The signs and symptoms of mask squeeze can take up to two weeks or more to resolve. Unfortunately, it is one of those conditions where you will probably look worse than you'd like before it gets better. Not only will blood and edema need to be reabsorbed, but it tends to be gravity-dependent - which means it will spread downward. Before your face is back to normal, you may look a bit like a red-eyed, black-and-blue marked creature in a B-grade horror movie, or a boxer that took at least a-couple-too-many punches!

Who gets mask squeeze?

It’s mostly new divers who get squeezed; they tend to be overwhelmed by all the skills they need to remember, such as buoyancy control and equalizing their ears and sinuses, all while being mesmerized by the underwater mysteries of the sea. More experienced divers, however, are not immune to mask squeeze. They tend to have mask squeeze when they are concentrating on some new activity or focused in on a task which diverts their attention from clearing their mask. High volume masks or those with stiff silicon or rubber (in the case of older masks) are more prone to exert suction on the face than the modern low volume collapsible masks. With the latter, pressure is often felt over the bridge of the nose as the mask volume collapses promptind divers to clear the mask. With all this in mind, a reasonable remedy would be to change to a new mask or to a lower-volume mask. Finally, poor-fitting masks or other issues such as facial hair may lead to problems with equalizing.

How do you prevent mask squeeze from happening again?

The best solution is remembering to keep your nasal passageways open during descent. By exhaling through your nose and using a properly-fitted mask, you will minimize the risk of facial barotrauma. A mask should fit comfortably against your face and you should be able to achieve an appropriate seal by gently placing the mask on your face and inhaling through your nose. The mask should seal to your face and not fall off even without the mask strap in place. It is not unusual for a small amount of leakage to occur while diving, especially if you have facial hair. Exhaling through your nose and tilting your face towards the surface while cracking the lower seal of the mask will generally remove any unwanted water from your mask.}

Posted in Dive Safety FAQ