Overview of Egophony
Even in this age of rapid technological progress, a detailed examination of someone’s breathing system is still important for diagnosing any problems they might have with their lungs or airways. One long-standing technique doctors use is listening to someone’s chest with a medical tool called a stethoscope. This easy, safe, and affordable technique helps doctors to determine how well air is flowing through a patient’s lungs.
Most lung diseases can be detected by changes in how this airflow sounds to the doctor. One such change is something called ‘egophony’, where your voice sounds more echoey or nasal when heard through your chest, a bit like a goat’s bleat. This happens when the ‘E’ vowel you say sounds more like ‘A’ because of changes in your lungs. These changes can include areas where the lung is solid or has fluid inside it, both of which selectively affect which sounds can pass through.
Egophony has long been recognized and various theories have been proposed over the years to explain it. The most accepted ones revolve around how the sound vibrations from the larynx (our voice box) and the windpipe and branching airways to the lungs interact with the state of lung tissue and surrounding areas.
In healthy lungs, there are lots of air pockets surrounded by firm lung tissue which we refer to as ‘parenchyma’. Egophony is often seen in conditions where this lung tissue becomes denser and less air-filled, such as pneumonia (where the lung becomes solid because of infection) and pleural effusion (where fluid accumulates in the lung).
This denser tissue prefers lower frequency sounds, like the ‘A’ sound. So, when you have pneumonia, the ‘E’ sound you make is transformed into an ‘A’ sound because it’s lower in frequency and better transmitted through the denser lung tissue.
In pleural effusion where there is excess fluid around the lung, this fluid makes the lung tissue more solid than usual, favoring the transmission of sounds of higher frequency. This alteration also results in egophony, particularly at the part of the lung where the fluid is most accumulated.
How is Egophony performed
When doctors want to examine your chest, they use four important methods: inspection (looking), percussion (tapping), palpation (touching), and auscultation (listening). They use these tactics to find clues about what might be going on with your lungs. To get the best results, they will have you remove your clothes and they will use a tool called a stethoscope to listen directly to your skin. They will listen to your chest from the front and back, and also near your armpit.
There are two types of sounds that lungs make when we breathe in and out: vesicular and bronchial.
Vesicular sounds are gentle, low-pitched sounds that are a bit like the rustling of leaves. When you breathe in (inspiratory phase), these sounds are made by air moving through smaller areas of your lungs, and when you breathe out (expiratory phase), the sounds come from air moving through bigger airways.
Bronchial sounds, on the other hand, are louder and high-pitched, like the sound a tube might make. These sounds normally can be heard when the doctor is listening to the center of your chest or back. If they hear these sounds in other places, it could mean that something is going on with your lungs. Some conditions that might cause this are pneumonia, pleural effusion (fluid around the lungs), pulmonary fibrosis (lung damage), atelectasis (collapsed lung), tension pneumothorax (a type of collapsed lung), or a lung mass (an abnormal growth).
Another part of the examination is listening to how your voice sounds when it’s transmitted through your lungs. Normally, these sounds can’t be heard, but if your lungs are filled with fluid or some other material, the doctor might be able to hear them. One such voice sound is called “egophony.” This is when the doctor asks you to say “Eee,” and if your voice sounds like a bleating goat (nasal or bleating quality), it suggests something might be going on with your lungs, like consolidation (when your lung becomes filled with fluid), pleural effusion, or a lung cavity.
There are a couple of other voice sounds the doctor might listen for. “Bronchophony” is when the doctor asks you to say “99,” and if it sounds louder or more distinct in certain areas, it could indicate consolidation. “Whispering pectoriloquy” is when the doctor asks you to whisper “1-2-3” or “99,” and if the whisper can be heard well in certain areas, it could also indicate consolidation. These various sounds give your doctor valuable information about the health of your lungs.
What Else Should I Know About Egophony?
Egophony, is a diagnostic technique used by doctors when they listen to your chest sounds when you speak. This technique can help them determine whether you have certain lung conditions.
For example, a study was carried out with 52 men who had symptoms of lower respiratory tract infection. They went to the emergency department of a Veterans Affairs medical center. Three examiners listened for chest sounds, including egophony. Of these men, 24 were found to have pneumonia through an X-ray. This study found that egophony was one of the more reliable indicators for pneumonia.
However, another review of 40 studies found that the reliability of egophony in diagnosing conditions like pneumonia varied quite a bit. Also, it’s unclear whether using egophony along with other physical signs, such as distinct percussion sounds and bronchophony (another way of analyzing chest sounds), improved the chances of making an accurate diagnosis.
Pneumonia and pleural effusion are two conditions where changes in chest sounds can be a useful clue. In pneumonia, egophony can help identify the affected side of the chest, along with other techniques such as listening to the vocal vibration over the chest (vocal fremitus), and other changes in breath sounds.
In pleural effusion (fluid buildup in the space between the lungs and chest wall), you might see less chest movement and a fullness of the spaces between the ribs on the affected side. Egophony along with reduced vocal resonance and breath sounds can be helpful in identifying the affected area.
In conclusion, the use of egophony amongst other physical signs can serve as a helpful indication when it comes to diagnosing pneumonia and pleural effusion, but the success rates can vary. Always see a medical professional if you suspect that you have either condition, as early treatment can significantly improve your prognosis.
