Verifying Bone-Anchored Hearing Devices with Sound Field Testing

When it comes to BAHDs, many audiologists rely on sound field threshold testing or aided sound field testing for verification. This involves placing the patient in a sound-treated booth while they wear their device—whether it’s secured by a soft band or connected via an abutment—and using age-appropriate methods to measure hearing thresholds.

Limitations of Sound Field Testing

Although sound field testing is commonly used to verify BAHDs, it’s important to understand its limitations.

Limitations include:
• Limited Real-World Representation: Sound field testing does not represent real-world situations and has limited frequency resolution.
• Inadequate Power Output Estimation: Sound field testing does not adequately estimate the device’s maximum power output.
• Poor Test-Retest Reliability: Poor test-retest reliability may exist, especially with pediatric patients who might perform differently on different days.

Objective Verification of BAHDs

While sound field testing provides useful information, it has challenges—especially when it comes to precision and repeatability. That’s where objective verification methods come in.

Objective verification uses specialized equipment to measure the performance of BAHDs without relying solely on patient feedback or behavioral responses. These methods are particularly helpful for:

• Patients who are too young or unable to reliably respond to behavioral tests
• Cross-checking aided thresholds obtained through sound field testing
• Fine-tuning device programming for more accurate and consistent amplification

One approach involves using skull simulators or couplers that mimic the mechanical properties of the human skull. These tools allow audiologists to evaluate the output of a BAHD under controlled, standardized conditions. The resulting data can be compared to target gain values to ensure the device is delivering appropriate amplification across frequencies.

Incorporating objective verification into your fitting process adds another layer of confidence—both for you and for your patients. It ensures that the BAHD is meeting its intended performance goals and supports better long-term outcomes.

The Verifit system, in conjunction with the Skull Simulator, utilizes DSL-BCD (Desired Sensation Level for Bone Conduction Devices) targets to ensure accurate and effective verification of BAHDs.

These targets are designed to account for the unique characteristics of BAHDs, providing age-appropriate prescriptive targets for adults and children. By measuring the device’s output in dB force level rather than dB SPL, the Verifit and Skull Simulator can objectively assess the performance of BAHD, ensuring optimal audibility and listening outcomes for patients.

This process helps audiologists fine-tune the settings to meet each patient’s specific needs, enhancing overall satisfaction and hearing aid effectiveness.

Verifit Compatibility

The Verifit Skull Simulator is compatible with the Verifit 2, which has software version 4.12 or later, and the Verifit 1 system, which has software version 3.20.x or later and serial numbers 2070 or later.

However, it’s important to note that as of January 1, 2024, Verifit VF-1 hardware and software are no longer supported, meaning no hardware parts, repair services, or software updates are available for all generations of Verifit VF-1.

Setting Up the Verifit Skull Simulator

Learn how to set up the Verifit Skull Simulator and start with Speechmap verification of bone-anchored hearing devices using the Verifit2 or Verifit1 test box.

Watch Now: Verifit Skull Simulator Set-up and Quick Start Guide

Verification of bone conduction devices is essential for ensuring optimal patient outcomes. Advanced tools like the Verifit Skull Simulator allow audiologists to provide accurate and reliable verification, improving audibility, listening outcomes, patient satisfaction, and fitting efficiency.

These verification protocols enhance the quality of care and support provided to patients with bone-anchored hearing aids.