2 Otology
2.2 Otitis Media
2.2.2 Chronic Otitis Media
and imbalance. Facial paresis or paralysis is rarely seen, but may be present with or without cholesteatoma.
Differential Diagnosis
Other than COM, painless otorrhea with a TM perforation may result from carcinoma of the TM or middle ear and can arise from ears with a history of COM. Any polypoid material removed needs to be sent for pathologic evaluation. Wegener granulomatosis may present in an adult as COM with fluctuating hearing loss and cranial nerve palsy without a previous history of OM. Tuberculous OM should be considered in a draining ear that does not improve despite maximal medical and surgical treatment. The clas- sic description of tuberculous OM is painless otorrhea with multiple TM perforations.
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Evaluation
Physical ExamThe physical exam focuses on the draining ear, and specifically on adequate visualization of the eardrum. Often inflammation, especially of the skin of the ear canal, must be controlled first. This may require treatment with topical or oral antibiotics. Once the canal edema has resolved, the TM is meticulously cleaned under an operating microscope. All debris and granulation tissue are cleaned, especially those covering the posterosuperior quadrant of the TM, and any tissue samples are sent to the pathology laboratory. Frequent cleaning and home ototopical medication with an acidic irrigation (acetic acid) may be needed prior to successfully drying the ear.
Imaging
Obtaining CT scans prior to surgical management is controversial, and de- pendent upon surgeon preference and training. Some surgeons will not scan any patients, some will scan only those with cholesteatoma, and some obtain CT scans for all patients being evaluated with COM. Most surgeons would agree that anyone suffering from a suspected intratemporal or intracranial complication of COM should be imaged with a high-resolution CT scan of the temporal bones with and without contrast. Also, anyone undergoing revision surgery should be imaged. CT scans yield information regarding disease and local anatomy that improves the informed consent process, and makes patients and especially parents more comfortable regarding the decision to undergo surgery.
Labs
Drainage, especially if recalcitrant to empiric therapy, should be cultured.
Aerobic and fungal cultures are routinely sent. Additional blood work is rarely indicated. If the onset of symptoms is bilateral, recent, and accompa- nied by fluctuating hearing loss, or cranial nerve palsy, then c-ANCA is sent to rule out Wegener granulomatosis.
Other Tests
An audiogram is obtained once the ear is dry and prior to any surgical intervention. A conductive hearing loss is expected, and a mixed loss is not uncommon. Some authors feel that COM can lead to SNHL over time.
Any granulation retrieved from the ear is sent to pathology to rule out carcinoma.
Pathology
The most common pathogens leading to COM are Pseudomonas aeruginosa and Staphylococcus aureus. They gain access to the middle ear through the perforated TM. They then spread from the middle ear to mastoid. These same pathogens can also colonize the avascular debris collecting within a cholesteatoma. A recent problem is the emergence of methicillin-resistant S. aureus (MRSA) COM.
The middle ear mucosa becomes thick, fibrotic, and infiltrated with inflammatory cells. Mucosal edema leads to polyp formation and granula- tion. Bony vascular channels embolize secondary to chronic inflammation, leading to bone erosion, particularly involving the ossicular chain. Cho- lesteatoma may erode bone by additional local inflammatory response and osteolytic enzymes.
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Treatment Options
The goals of treatment are elimination of infection and restoration of function.
Medical
In many cases, medical therapy is employed to dry disease preoperatively, permit better office assessment, or manage the patient with comorbidities in whom surgery is contraindicated. COM may be initially treated with empiric ototopical antibiotic drops. Awareness of ototoxicity has made fluoroquinolone drops the preferred method of treatment. Ototopical drops reach the middle ear in such high concentrations, that resistance is rarely an issue. See Table 2.4 for topical treatment options. If the drainage does not respond, then cultures are indicated to rule out a rare resistant strain such as MRSA or a fungal infection. Vinegar washes or 2% acetic acid drops may be effective. There are several topical powders that also may periodically be applied if drops do not work. One such mixture includes ciprofloxacin, boric acid, dexamethasone, and fluconazole. Appropriate long-term IV antibiotics may also be indicated if an osteitis is suspected. Another effective topical powder preparation to help dry the chronically draining ear that is unre- sponsive to drops is chloramphenicol 50 mg, p-aminobenzenesulfonamide 50 mg and amphotericin 5 mg, with or without hydrocortisone 1 mg; this is mixed and delivered 1 or 2 puffs via a powder insufflator (e.g., OTOMED, Lake Havasu City, AZ) twice daily. Another option for office management is aqueous gentian violet, which has antifungal properties, and may be
“painted” over inflamed areas under the otomicroscope.
Surgical
There are multiple reasons to operate for COM. The infection and drainage can be eradicated, the TM can be repaired, the hearing can be improved, and in the case of cholesteatoma, the disease can be removed and the ear made safe. It is better to dry the ear prior to surgical intervention, but sometimes it is not possible. In cases of drainage at the time of surgery continue with culture-directed antibiotics in the preoperative and postoperative period.
Surgical algorithms vary by preference, training, and experience. The fol- lowing is a general list of options (nonexhaustive) with definitions.
1. Tympanoplasty without mastoidectomy: eradicating disease limited to the middle ear, whether TM grafting is or is not required. Otorrhea can be controlled, the TM repaired, middle ear cholesteatoma removed, and hearing improved or stabilized. TM grafting material includes loose areolar tissue, temporalis fascia, perichondrium, vein, or cartilage. The graft can be placed either medial or lateral to the TM.
2. Atticotomy: during tympanoplasty, but without performing a mas-