The Lateral Air Hook is a product that was researched and developed by audiologists, for the purposes of improving patient comfort and earwax removal efficiency during aural microsuction.
Removal of earwax, especially in more tightly occluded canals has been proven to be far quicker using the larger diameter tube that we’ve named the Lateral Air Hook.
Increasing the diameter, improves airflow and therefore suction strength but it also increases noise and reduces peripheral vision. Therefore, developing the Lateral Air Hook has been a process of finding the right balance of these 4 factors:
- Suction Strength (Airflow)
- Patient Comfort (Noise)
- Peripheral Vision (Tube Size)
- Safety
The audiologists involved in the development were unanimous on the tube with an internal diameter of 2mm and an external diameter of 2.48mm. By comparison, standard suction tubes have an internal diameter of 1.6-1.7mm and an external diameter of approximately 2.1mm. The increase in internal tube diameter represented a significant increase in comfort for the patient and efficient earwax removal.
A number of different diameters of tubing were tested and it was concluded that a 2mm internal diameter had the right balance of added efficiency and not too much extra noise. It's important to note that a skilled practitioner tries to limit the amount of free-flowing air in the patient's ear at all times during any procedure so any noise from any tube should always be kept to a minimum. We are developing a fenestrated (Control Hole) version to help further with this.
Tests were conducted in a completely clear ear with a New Hospivac 400 with 90l/min air flow. This probably represents a "worst-case" scenario in terms of noise.
The word ‘Lateral’ has been used to stress that it should only be used in the outer third of the ear canal for practitioner vision and patient noise reasons. The phrase ‘Air Hook’ is to indicate the added removal power whilst still being more comfortable than a dry removal tool.
When used in the outer third, the peripheral vision isn’t an issue in most cases. The Lateral Air Hook used at the first bend of the canal produces approximately the same level of airflow noise as when a regular tube is used on the second bend of the canal. As a reminder, lateral in anatomy means towards the outside of the body and we specifically mean the outer third of the canal with regards to this product.
Below are the REM results for the Lateral Air Hook vs a standard suction tube. We have been testing these in Liverpool Hearing Centre for well over 12 months and with our Aural Microsuction Course Trainers. The main comment is that they really save time with the more occluded ears.
As you can see in the diagram, the Lateral Air Hook's air flow noise is loud even at the first bend and then exceptionally loud at the second hence the reason for stressing where in the canal these tubes should be employed. If the wax continues towards the middle of the canal then the Lateral Air Hook should be replaced with a standard tube. However, it should also be considered that a fully occluded ear will not hear very much anyway and therefore isn't at any risk from noise.
With either aural microsuction or irrigation, the risks of tinnitus and hearing loss are always there and it is down to the professionalism of the practitioner to make the right decisions at the right times to limit these risks.