Diseases & conditions A-Z List
Diseases & Conditions A-Z List - «O»:
Obesity is a term used to describe body weight that is much greater than what is healthy. If you are obese, you also have a much higher amount of body fat than is healthy or desirable.
Adults with a body mass index (BMI, calculated as weight in kilograms divided by height in meters squared) between ...
Obesity hypoventilation syndrome (OHS)
Obesity hypoventilation syndrome (OHS) is a condition that occurs in obese people, in which poor breathing leads to lower oxygen levels and higher carbon dioxide levels in the blood.
The exact cause of OHS in unknown. Most (but not all) patients with the syndrome have a form of sleep apnea.
Obsessive-compulsive disorder is an anxiety disorder in which people have unwanted and repeated thoughts, feelings, ideas, sensations (obsessions), or behaviors that make them feel driven to do something (compulsions).
Often the person carries out the behaviors to get rid of the obsessive thoughts, ...
Obsessive-compulsive personality disorder
Obsessive-compulsive personality disorder is a condition in which a person is preoccupied with rules, orderliness, and control.
This disorder tends to occur in families, so genes may be involved. Obsessive-compulsive personality disorder most often occurs in men.
Obstructive sleep apnea
Obstructive sleep apnea is a condition in which a person has episodes of blocked breathing during sleep.
This article discusses obstructive sleep apnea in adults.
Central sleep apnea
Normally, the muscles of the upper part of the throat help keep the airway op...
Obstructive uropathy is a condition in which the flow of urine is blocked, causing it to back up and injure one or both kidneys.
Obstructive uropathy occurs when urine cannot drain through a ureter (a tube that carries urine from the kidneys to the bladder). Urine backs up into the kidney an...
Occupational asthma is a lung disorder in which various substances found in the workplace lead to breathing difficulties.
Many substances in the workplace can cause occupational asthma. The most common triggers are wood dust, grain dust, animal dander, fungi, or other ch...
Occupational hearing loss
Occupational hearing loss is damage to the inner ear from noise or vibrations due to certain types of jobs or entertainment.
Occupational hearing loss is a form of acoustic trauma caused by exposure to vibration or sound. Sound is heard as the ear converts vibration from sound waves into imp...
Here are some tips for preventing and treating oily hair:
Shampoo your hair every day. Leaving the shampoo on your head for at least 5 minutes before rinsing may help.
Avoid brushing your hair too often or too vigorously, since the brushing will carry oil from your scalp to the ends of your hair.
Oleander poisoning occurs when someone sucks nectar from the flowers or chews leaves from the oleander or yellow oleander plant. Poisoning can also happen if you eat honey made by bees that used the oleander plant for nectar.
This is for information only and not for use in the treatment or managemen...
Olivopontocerebellar atrophy is a disease that causes areas deep in the brain, just above the spinal cord, to shrink.
Olivopontocerebellar atrophy can be passed down through families (inherited form), or it may affect people without a known family history (sporadic form).
The cause of olivop...
An omphalocele is a birth defect in which the infant's intestine or other abdominal organs stick out of the belly button (navel). In babies with an omphalocele, the intestines are covered only by a thin layer of tissue and can be easily seen.
An omphalocele is a type of hernia. Hernia means "rupture...
Omphalocele repair is surgery to repair a birth defect in the wall of the belly (abdomen) in which all or parts of the small intestine, liver, and large intestine stick outside the belly in a thin sac. organs come out through an opening at the base of the umbilical cord.
Gastoschisis (a ...
Open heart surgery
Open heart surgery is any surgery where the chest is opened and surgery is performed on the heart muscle, valves, arteries, or other heart structures (such as the aorta). The term "open" means that the chest is "cut" open.
A heart-lung machine (also called cardiopulmonary bypass) is usually used dur...
Open lung biopsy
An open lung biopsy is surgery to remove a small piece of tissue from the lung. The sample is then examined for cancer, infection, or lung disease.
How the Test is Performed
An open lung biopsy is done in a hospital operating room under general anesthesia, which means you are asleep and pain-free. ...