Issues & Impact

Effects on diagnosis

Issues

The quality of swallow media in impedance-manometry esophageal motility testing is extremely important. This media is used to measure pressure in the esophagus as it is swallowing a material, and swallow media with lots of air noise will produce poor quality ultrasound images. As the testing procedures are quite invasive and cause patient discomfort, we want to make sure that only the highest quality swallow media is used in order to prevent inaccurate or inconclusive diagnoses. An inconclusive diagnosis means that the patient must repeat an invasive testing procedure to get better results. On the other hand, an inaccurate diagnosis is even worse, as patients won't be properly treated for their condition.

Impact

The impact of our high-quality gel as a swallow media has already been beneficial. Our product was used in the testing of a patient who was initially diagnosed with functional dysphagia. However, during the test, the patient struggled with swallowing the viscous gel, revealing unexpected pressure in the upper esophageal sphincter, shown in the figure below. This led to a change of diagnosis to a botox injection which relaxes the upper esophageal sphincter, instead of the invasive surgery for functional dysphagia patients that permanently decreases their quality of life. Our high-quality viscous gel has already begun to help patients with esophageal motility disorders.

Impact on a real patient

This pressure diagram was taken from a motility test using our gel. The top of the multi-colored pressure diagram indicates the upper esophageal sphincter, which reads unexpectedly constant high pressure by the presence of the pink region. In a healthy human swallow, high pressure in the upper esophagus is present only at the beginning of the swallow. As the swallowed material moves down the esophagus, the upper esophagus decreases in pressure.

Effects of degassing

Issues

Chemical degassing

Most of our products in the prototyping phase were degassed through the use of a chemical degassing agent due to convenience. In addition, the presence of the degassing agent reduced the amount of bubbles on the surface of the viscous gel. However, the addition of this agent changed the chemical properties of our product significantly. The changes were:

Conductivity variance: Between the non-degassed products and degassed products, the degassed products contained significant conductivity differences between the top layer and the bottom layer.
Viscosity variance: High concentrations of one of our tested chemical degassing agents can significantly change the viscosity of our viscous gel, as measured by the viscometer. This complicated our goals of standardization in viscosity.
Poor ultrasound image quality: When the chemical-degassed product was used to take an ultrasound image, the quality of the ultrasound was equivalent to using Diversatech gel, which is swallow medium currently available on the market. Ultrasound images from this gel swallow medium are of poor quality and renders difficulty in calculating cross-sectional area of the patient's esophagus.

Heat degassing

Due to the issues that came up with chemical degassing, we switched to heat degassing in the final weeks of the project for further patient testing. We were reluctant to switch to heat degassing in the earlier stages, as heat degassing causes changes in viscosity that would affect our standardization.

Impact

Regarding the issues for chemical degassing, the purpose of degassing the product is to improve ultrasound image quality. However, since chemical degassing produces poor quality ultrasound images despite the decreased air, this solution is not effective in meeting our goals.

As for heat degassing, we utilized a method where we increased the temperature of the gel as little as possible while maintaining effective degassing. This proved to be extremely effective by producing a high-quality ultrasound image while maintaining a viscosity similar to gels already on the market.

In conclusion, heat degassing has been effective in significantly improving esophageal ultrasound quality when compared to chemical degassing for the viscous gel swallow media.

Diversatech Gel

This is the ultrasound image taken from a patient who used Diversatek gel as a swallow medium. Notice that the shape of cross-sectional area of the esophagus is extremely unclear.

Chemically-degassed gel

This is the ultrasound image taken from a patient who used our chemically-degassed gel as a swallow medium. Notice that the shape of cross-sectional area of the esophagus is extremely unclear.

Heat-degassed gel

This is the ultrasound image taken from a patient who used our heat-degassed gel as a swallow medium. Notice that the shape of the cross-sectional area of the esophagus is clear, allowing physicians to calculate the area using this image.

<-- Project Management

Page credits: Michelle Liem

Page updated

Report abuse