Hearing Loss (Deafness)
William C. Shiel Jr., MD, FACP, FACR
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
Melissa Conrad Stöppler, MD
Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
What are forms of hearing loss?
Hearing loss, or deafness, can be present at birth (congenital), or become evident later in life (acquired). The distinction between acquired and congenital deafness specifies only the time that the deafness appears. It does not specify whether the cause of the deafness is genetic (inherited).
Acquired deafness may or may not be genetic. For example, it may be a manifestation of a delayed-onset form of genetic deafness. Alternatively, acquired deafness may be due to damage to the ear due to noise or from other conditions.
Congenital deafness may or may not be genetic. In non-genetic causes, congenital deafness may be due to a condition or infection to which the mother was exposed during pregnancy, such as the rubella virus. Alternatively, congenital hearing loss may be associated with certain other characteristic findings. Fore example, a white forelock may be a sign of a genetic disease called Waardenburg syndrome that includes congenital deafness in the spectrum of disease. Overall, more than half of congenital hearing loss is inherited.
What are the types of hearing loss?
Hearing loss can also be classified based on which portions of the hearing system (auditory system) are affected. When the nervous system is affected, it is referred to as sensorineural hearing loss. When the portions of the ear that are responsible for transmitting the sound to the nerves are affected, it is referred to as conductive hearing loss.
Conditions affecting the cochlea, eighth cranial nerve, spinal cord, or brain cause sensorineural hearing loss. Examples include:
- Meniere's disease,
- noise-induced hearing loss (such as prolonged or excessive exposure to loud music or machinery),
- hearing loss of aging (presbycusis),
- nerve injury from syphilis,
- hearing loss of unknown cause (idiopathic hearing loss),
- nerve tumors and;
- drug toxicity (such as aspirin and aminoglycosides).
Conditions that affect the ear canal, eardrum (tympanic membrane), and middle ear lead to conductive hearing loss. Examples of conductive hearing loss include:
Find out what women really need.