What are the diagnostic and treatment approaches for cholesteatoma?

Cholesteatoma Diagnosis

For initial diagnosis of cholesteatoma, begin with otoscopic examination by an otolaryngologist, followed by CT temporal bone without IV contrast for presurgical planning and MRI head and IAC without and with IV contrast (including non-echoplanar DWI in coronal plane) for definitive tissue characterization.

Clinical Diagnosis

• Cholesteatoma typically presents with painless otorrhea and characteristic tympanic membrane findings including perforation, retraction pockets, and granulation tissue 1
• Any patient with suspected cholesteatoma requires referral to an otolaryngologist for definitive management 1
• The diagnosis is primarily clinical through otoscopic examination, though imaging is essential for surgical planning 2, 3

Initial Imaging Strategy

CT Temporal Bone Without IV Contrast (First-Line for Surgical Planning)

CT temporal bone without IV contrast is the cornerstone imaging modality for presurgical planning when cholesteatoma is suspected 4

• CT provides excellent anatomic detail of bony structures and determines the extent of disease in the middle ear and mastoid 4
• CT accurately detects ossicular erosion (malleus, incus), scutum erosion, tegmen erosion, and lateral semicircular canal erosion 4, 3
• CT helps identify potential surgical hazards including anatomic variations (low-lying dura, high jugular bulb, anterior sigmoid sinus) and disease complications 5
• Preoperative HRCT combined with audiological assessment provides good estimates of ossicular erosion degree 4, 1

Important Limitation: CT cannot distinguish cholesteatoma from other soft tissue masses (granulation tissue, mucosal disease, scar) due to poor soft tissue specificity 2, 6

MRI Head and IAC Without and With IV Contrast (For Tissue Characterization)

MRI with non-echoplanar diffusion-weighted imaging (DWI) in the coronal plane is essential for differentiating cholesteatoma from other soft tissue pathology 4

• DWI MRI differentiates cholesteatoma from scar tissue and inflamed granulation tissue with high sensitivity and specificity 4
• Non-echoplanar DWI provides superior diagnostic accuracy compared to conventional MRI sequences 4, 6
• Coronal plane imaging is preferred for optimal visualization 4
• MRI is particularly valuable when CT shows soft tissue but cannot determine its nature 4

Critical Point: MRI without IV contrast alone or with IV contrast alone are inadequate—both sequences are required together 4

Postoperative Surveillance for Recurrence

CT Temporal Bone Without IV Contrast

CT temporal bone without IV contrast is the primary modality for detecting recurrent cholesteatoma 4, 1

• CT detects abnormal, new, or enlarging lobulated material in the temporal bone region 4, 1
• CT identifies subtle osseous erosions that increase suspicion for recurrence 4, 1

MRI Head and IAC Without and With IV Contrast

MRI with DWI and delayed postcontrast T1-weighted imaging differentiates recurrent cholesteatoma from postoperative granulation tissue and scar 4, 1

• This distinction is critical as CT cannot differentiate keratinous debris from non-cholesteatoma findings postoperatively 4

Common Pitfalls

• Do not order CT with IV contrast—there is no evidence supporting its use, and the non-contrast portion provides all necessary bony detail 4
• Do not rely on CT alone for tissue characterization—it has poor specificity for distinguishing cholesteatoma from other soft tissue masses 2, 6
• Do not order MRI without both pre- and post-contrast sequences—both are required for optimal evaluation 4
• CT has poor accuracy for detecting facial nerve dehiscence and stapes erosion—warn surgeons of this limitation 2, 3
• Plain radiography (skull films) has no role in cholesteatoma diagnosis or surveillance 4

Treatment Approach

Surgical excision is the only definitive treatment for cholesteatoma 3

• The imaging findings guide surgical approach and alert surgeons to potential complications 4, 5
• Preoperative imaging affects decisions regarding operation type and helps anticipate anatomic difficulties 4