A Body Mass Index (BMI) at or above the 95th percentile for children of the same age and gender, possibly resulting in high blood pressure, type 2 diabetes, sleep apnea, asthma, etc.

Obsessive compulsive disorder (OCD) starts in adolescence or young adulthood and involves both thoughts and behaviors that are hard to control. Learn more.

Intervals of no airflow through the nose and mouth during sleep despite continued attempts to breathe in and out.

A broad term referring to any disease of the upper or lower urinary tract that restricts the flow of urine, among common congenital urinary tract abnormalities in children.

Lurie Children's provides specialized pediatric occupational therapy services for children of all ages, from infancy to adolescence.

An assortment of congenital malformations that affect various parts of the head and upper body.

The pediatric ophthalmologists at Lurie Children's provide world-class treatment for eye disorders, trauma, and vision problems in children.

Optic neuritis is the inflammation and swelling of the optic nerve. The optic nerve connects the back of the eye to the brain and transmits signals allowing sight.

Oral immunotherapy (OIT) “retrains” the immune system to be less reactive to allergenic foods by feeding a patient increasing doses of the allergen over time.

An orbital fracture is a condition where one or more bones surrounding the eye are broken. Learn more.

Lurie Children's Orofacial Myofunctional Therapy Program specialists are trained in the evaluation and treatment of swallowing and disorders of the structures of the lips, tongue, jaw, cheeks and palate.

Orthopedic Surgery at Lurie Children’s provides a range of services for children with bone, joint, muscle, ligament, tendon and nerve (musculoskeletal) disorders.