Chronic otitis media requiring modified radical mastoidectomy (MRM) often leads to postoperative challenges, particularly maintaining a dry and healthy mastoid cavity. Persistent otorrhea and granulation tissue impede healing and patient satisfaction. Acetic acid, owing to its antimicrobial and tissue cauterization properties, has been widely used to aid postoperative cavity care.1 This review systematically assesses the published evidence regarding its efficacy and safety in MRM cases.

Inclusion Criteria: Studies involving postoperative use of acetic acid in MRM cases, with objective measures of cavity dryness or granulation.

Databases Searched: PubMed, Scopus, Medline, and indexed ENT journals.

Data Extraction: Sample size, concentration of acetic acid, frequency of \ application, time to dry cavity, incidence of granulation, complications.

Data were synthesized from studies including a combined 60+ patients who received 4%–12.5% acetic acid post-MRM. All patients were adults or older children with chronic suppurative otitis media or cholesteatoma.

Table 1: Summary Table of Key Findings

        *Subset of larger cohort treated primarily with acetic acid.

Key Points

• Early Dry Cavity Achievement: Studies showed nearly all patients treated with 4% acetic acid thrice daily achieved a dry cavity by 6–8 weeks; less frequent dosing resulted in delayed dryness.
• Reduction of Granulation: Compared to mitomycin C, acetic acid was less potent but still led to a substantial reduction in granulation tissue over three months. Most patients still experienced a decrease in granulation with regular acetic acid use.
• Complications: No major adverse effects were reported. Some patients experienced mild irritation or transient discomfort, which resolved without intervention.
• Comparison to Other Treatments: Mitomycin C² achieved faster dryness and greater granulation reduction but is costlier and not universally available. Acetic acid thus remains a practical mainstay, especially in resource-limited settings.

The evidence supports the use of acetic acid as a standard adjunct in postoperative care following MRM. Dosing protocols of 4% solution applied generously 3 times daily for at least 6–8 weeks produced robust outcomes. Less frequent or lower-concentration instillation was associated with delayed cavity healing and persistent granulation. While alternatives like mitomycin C may offer incremental improvements, acetic acid’s accessibility, safety, and efficacy solidify its role.3

Limitations

• Variation in concentration and frequency of acetic acid among studies.
• Randomization and blinding inconsistencies across clinical trials.
• Limited high-quality, large-scale RCTs in this domain.

Postoperative acetic acid irrigation after MRM is highly effective in achieving early cavity dryness and minimizing granulation tissue, especially when used in adequate concentration and frequency. It is a cost-efficient, safe, and practical approach warranting routine postoperative recommendation.

1. Shetty H, K S G. Acetic Acid Instillation after Canal Wall Down Mastoidectomy. BJOHNS. 2015;23(3):104-8.
2. Karimi-Yazdi A, Amiri M, Rabiei S, Amali A, Motiee-Langroudi M. Topical application of mitomycin C in the treatment of granulation tissue after canal wall down mastoidectomy. Iran J Otorhinolaryngol. 2013 Spring;25(71):85-90.
3. Mousumi Modhumita Agarwala, Debajit Sarma, Manaswi Sharma Rupanjita Sangma, Dhritiman Dey. Complications of Mastoid Surgery: A Descriptive Study from a Tertiary Care Centre, Assam, India. JCDR;2024:18(6): MC01-MC04.