Hemidystonia-hemiatrophy (HD-HA) is a rare dystonia, usually caused by a static cerebral injury occurring at birth or during infancy, that is characterized by a combination of hemidystonia (HD), involving one half of the body, and hemiatrophy (HA) on the same side as the HD.

Abnormality of the paranasal (cranial) sinuses, which are air-filled spaces that are located within the bones of the skull and face and communicate with the nasal cavity. They comprise the maxillary sinuses, the frontal sinuses, the ethmoid sinuses, and the sphenoid sinuses.