A sleep study is a way to measure what's going on during a child's sleep. It's also known as a polysomnogram. It is a painless test done overnight in a hospital or clinic.

Here are images that show the steps of using an inhaler without a spacer.

Here are images that show the steps of inhaler use without a spacer.

Bariatric surgery is a type of surgery to help you lose weight by making changes to your digestive system. It's a choice for some people who are obese and not able to lose weight with other methods. It may also be a choice if you're overweight and have a health problem.

Convergence insufficiency (CI) is a problem with the way the eye moves. It makes it hard to focus on things nearby. When the eyes converge, it means they point inward (toward the midline) to focus on something close. With CI, the eyes have trouble doing this. One eye may turn out instead of looking inward. CI can cause blurred vision, double vision, and eyestrain.

A carotid dissection is a tear in the inner layer of an artery in the neck. You have one carotid artery on each side of your neck. These arteries send blood to your brain.

Dysphagia is trouble swallowing normally. A dysphagia diet is a way of eating and drinking that is safer for a person who has trouble swallowing. It helps to prevent aspiration. On a dysphagia diet, only certain kinds of liquids are safe to drink.

Knee pain is very common. Here is general information about symptoms, diagnosis, and treatment.

Thoracic outlet syndrome is a set of symptoms in the shoulder, arm, or hand. It occurs from a narrowing of the thoracic outlet. This is the space between your collarbone and your first rib.

A subconjunctival hemorrhage is when a blood vessel breaks open in the white of the eye. It causes a bright red patch in the white of the eye. It is similar to a bruise on the skin. This type of hemorrhage is common. It can look quite alarming, but it is usually harmless.