Cholesterol granuloma is a cyst-like problem that develops in the temporal bone. Cholesterol granulomas are filled with thick fluid on the inside and surrounded by a thin wall. The usual location in in an area of the temporal bone called the petrous apex. Cholesterol granuloma is thought to occur in which a small amount of exposed bone marrow or blood product walls itself from allowing air to flow in this area and becomes irritative. Cholesterol granulomas are benign, however they slowly expand and erode bone. Symptoms include hearing loss, ringing of the ear ("tinnitus"), pain behind the eye or ear, facial muscle weakness, numbness or pain of the face, and vision problems.
The diagnosis of cholesterol granuloma is made by MRI. Often a CT scan in addition to the MR can help provide further evidence to aid in the diagnosis and in potential treatment planning.
Watchful waiting (observation) and surgery are the two ways to manage cholesterol granulomas. Size of the cholesterol granuloma, age of the patient, degree of hearing loss, and presence of symptoms all help determine how a cholesterol granuloma is managed.
In some cases of cholesterol granuloma observation is the best initial management. In such cases repeated imaging with either a MR or CT scan will often be needed.
In other cases, surgery may be the preferred management option. The goal of surgery when warranted is to create a drainage pathway to stop the cholesterol granuloma from continuing to create symptoms. The petrous apex is surrounded by many important structures including the inner ear that controls hearing and balance. In cases in which surgery is offered, the surgical approach depends of the patient's anatomy and hearing ability. In patients with good hearing the cholesterol granuloma can be drained by going under (infraochlear approach), behind (infralabyrinthine approach) or above (middle fossa approach) the inner ear. In cases where the cholesterol granuloma has done permanent and severe damage to hearing on that side, going through the inner ear (either translabyrinthine or transcochlear approaches) allows the most direct route to drain the cholesterol granuloma.
Dr. Slattery is skilled in all management options for cholesterol granuloma.