CT scans are frequently used to evaluate the temporal bones. Temporal bone CTs, also known as mastoid bone CTs are typically ordered to evaluate the outer ear, bones of the ear and inner ear structures for infection, tumor, injury or congenital or acquired hearing disorders. Below are a few common diagnoses that a CT scan of the temporal bones detect.
Mastoiditis - This is an infection of the air filled parts of the temporal bone, located just behind your ear. The infection can be aggressive and erode the bone. Symptoms include dizziness, hearing loss, and pain for example. In extreme cases the infection can extend to the nearby brain. This can cause seizures.
Tumors - Tumors can be from the temporal bone itself or arise in and around the ear structures. These tumors can be either benign or malignant. Some tumors that affect this area include basal cell carcinoma, cholesteotomas, schwannomas, neuromas, and cholesterol granulomas. Symptoms vary but can include pain, hearing loss, and dizziness.
Trauma - In severe head injuries, the temporal bone can fracture and injure the bones of the ear, the nerves that carry sound or damage the facial nerve (and cause facial paralysis).
An CT scan of the temporal bones will evaluate:
External ear
The outer ear, nearby tissues and the ear canal are well seen and part of the evaluation of the temporal bones. A temporal bone CT can evaluate a severe swimmer's ear infection - otitis externa. Surfer's also develop a bony growth in the ear which can lead to hearing impairment. This is called Surfer's ear.
Middle ear
This includes the ear bones (ossicles) and bone cavities that are involved in transmitting sound. Otitis media is an infection centered in the middle ear.
Inner ear
This portion of the ear acts as the first point of sound processing and is protected by the temporal bone. It has nerves which conduct sound and spatial sensation to the brain.
Sinuses
Portions of the sinuses are seen in a temporal bone CT and sinus disease may be detected.
Skull base
The skull base is a complex set of bones that protect and surround parts of important vessels and nerves. Erosion or injury to the bone can damage these structures. The carotid arteries which feed parts of your brain travel through the skull base.
Your Temporal Bone CT Scan
A temporal bone CT scan generally takes about 5 to 10 minutes or to complete. If you are going for one remember to remove hair pins, nearby piercings, earrings and necklaces as these metallic objects can interfere with the scan. These scans are done without IV contrast.
If you're insured, you may need to have your test authorized (approved) by your insurance company first. If you're uninsured and need to look up prices and buy an CT scan of the brain, you can use our website to look up CT scan costs and then purchase with your credit card.
Have you had a Temporal Bone CT scan? What was it like? Please leave your comments below.