Research Gaps - Cerumen Impaction
While there is a body of literature from which these guidelines were drawn, significant gaps in our knowledge about cerumen impaction and its management remain. The guideline committee identified several areas where further research would improve the ability of clinicians to optimally manage patients.
1. The exact definition of cerumen impaction is variable and elusive. We used an operational definition for this guideline, but establishing a universal definition would lend standardization to all future studies and make comparison of management strategies more meaningful.
2. The natural history of impacted cerumen is also not well known. There is evidence that some impactions may clear spontaneously, but a longitudinal study documenting the likely outcome of cerumen managed by observation alone would guide clinicians as to the necessity of any intervention in the nonemergent setting. Similarly, the role of preventive measures such as emollients and ear hygiene merits further study in a controlled fashion. Additionally, these studies should stratify patients by age as the natural history and effect of preventive measures may vary by age.
3. The bulk of high-quality studies in the existing cerumen literature evaluated and compared different cerumenolytic agents alone or in combination with syringing. The committee saw significant room for further large and well-constructed randomized controlled trials comparing the different methods for cerumen removal alone or in combination. There are little data on manual removal other than syringing. While it was the opinion of the committee that this is an effective method with limited risk when performed by adequately trained practitioners, there were virtually no data to confirm this widely held conviction. Furthermore, the impact of different interventions on different age groups and special populations bears study. Cerumenolytic agents and irrigation might be more or less effective in children, the elderly, or other high-risk groups relative to adults. Relative cost data for the different treatment options are lacking and would be a useful addition to future guidelines. In addition, given that EAC trauma is a common complication of instrumentation, resulting in otitis externa, more information is needed on the efficacy of prophylactic topical antimicrobials when EAC trauma occurs.
4. Ear candling and other alternative medical approaches to cerumen removal are commonly practiced. There are very limited data on their effectiveness or lack thereof. There are reports of adverse events and limited effectiveness of these therapies, but prospective controlled studies are warranted to establish what role, if any, these therapies have in managing patients with otologic complaints and to better define the risks associated with their use.
5. All studies demonstrated limited outcomes data. Whether or not the impaction is cleared is an obvious outcome, but frequently cerumen is removed to alleviate symptoms such as pruritis, hearing loss, pain, fullness, tinnitus, or vertigo. An additional area of interest would be to determine if different types or consistencies of cerumen should be managed differently. The committee recommends that future studies of treatment effectiveness take these alternative outcomes into account. In the same regard, reports of the risks of cerumen removal are largely anecdotal. All trials of treatment effectiveness should clearly document adverse events.
6. Finally, in clinical practice, different levels of healthcare providers are involved in managing patients with cerumen impaction. Studies evaluating the safety and efficacy of one therapeutic option over another; resource use; and cost of cerumen management and post-treatment assessment by the various provider types are warranted.