What is the Difference Between Keratosis Obturans and Cholesteatoma?

Keratosis obturans and cholesteatoma are two distinct conditions that affect the external auditory canal (EAC). They have different clinical presentations, physical findings, and treatments:

Keratosis Obturans:

• Characterized by an accumulation of obstructive desquamated keratin in the EAC.
• Associated with a greatly widened ear canal from circumferential erosion of bone.
• There is an associated hyperplasia of the underlying epithelium and evidence of chronic inflammation.
• No evidence of erosion or necrosis of the underlying bone.
• Can be managed successfully by regular aural toilet.

Cholesteatoma:

• Characterized by an invasion and erosion of squamous epithelium into a localized area of the bony ear canal.
• Associated with extensive erosion of the bony lined with stratified squamous keratinizing epithelium, that arises lateral to the tympanic membrane and is located in the inferior portion of the bony EAC.
• Frequently evidence of sequestration of the underlying bone.
• May require surgical intervention depending on the extent of the condition.

While both disorders have some overlapping characteristics, they are considered separate entities with distinct features. The presence of osteonecrosis and focal sequestration of the underlying bone are indicators that differentiate cholesteatoma from keratosis obturans.

Comparative Table: Keratosis Obturans vs Cholesteatoma

Here is a table comparing the differences between keratosis obturans and cholesteatoma:

While both keratosis obturans and cholesteatoma are separate entities with distinct characteristics, they do share some overlapping features, which can make it challenging to differentiate between them.