Diagnostic Considerations
A high index of suspicion, judicious use of diagnostic modalities, and close follow-up care are recommended to make a diagnosis in a timely manner
Conditions to consider in the differential diagnosis of mastoiditis include the following:
-
Basilar Skull Fracture
-
Cellulitis
-
Cysts
-
Deep Neck Infections
-
Lymphadenopathy
-
Parotitis
-
Stroke
-
Trauma
-
Tumors
-
Histiocytoses
-
Sarcoidosis
-
External otitis
-
Mastoid trauma
-
Suppuration of postauricular lymph node
-
Furuncle of meatus of the ear
-
Suppuration of the postauricular (mastoid) lymph node - This node collects drainage from the scalp and becomes inflamed with infections involving this region
Catscratch disease and atypical mycobacteria tend to have poor response to antimicrobials and a high frequency of nodal abscess formation. Differentiation from acute surgical mastoiditis (ASM) is relatively easy with preservation of the skin crease and presence of a normal middle ear.
Lateral sinus thrombosis causes mastoid air sinus abnormalities; this is due to venous congestion as a consequence of this condition.
Differential Diagnoses
-
Otitis Externa
-
Otitis Media
-
Wegener Granulomatosis
-
Mastoiditis with subperiosteal abscess. Note the loss of the skin crease and the pointed abscess.
-
Cortical mastoidectomy in a densely sclerosed mastoid.
-
Preoperative preparation of the patient.
-
Draping the surgical area.
-
Injection of the area with 2% Xylocaine and 1:100,000 adrenaline to reduce bleeding.
-
Marking the incision site.
-
Placement of the incision, a few mm behind the postauricular sulcus.
-
Deepening the incision down to the bone.
-
Elevation of the periosteum to expose the mastoid cortex to the mastoid tip.
-
Mastoid drilling in progress with simultaneous saline irrigation.
-
Creation of the initial groove and the vertical line.
-
Exposure of the antrum and exenteration of the mastoid air cells.
-
Curetting the aditus to enlarge it.
-
Further exposure.
-
Healed postaural scar.
-
Extent of cortical mastoidectomy in a well-pneumatized mastoid.