First a story:
A young woman describes a feeling of something going on in her throat one afternoon. Then her voice just seems to disappear over the next few hours, but she does not have any other symptoms. By evening, when she tries to speak, her vocal volume is not much more than a whisper. Thinking this is just the beginning of laryngitis, and because work is busy, she waits for a week. When she does not seem to be getting better she calls her primary care physician and makes an appointment.
At the physician's office, the nurse takes her blood pressure. The physician listens to her heart and lungs. He palpates her neck for swollen glands, looks into her ears, and of course, into her mouth. The physician asks her to open her mouth, say “ah” and looked in with a small light. He suggested that her voice would get better with time and she should just wait and see what happens.
Is his advice appropriate? Can he see the vocal cords by aiming a light into the mouth?
Maybe and No.
How do we know the second answer is no? The vocal cords are located around a bend in the throat. At a minimum, it takes an angled mirror, placed in the back of the mouth to see the vocal cords. Even then, the view can be quite fleeting because of gagging, needing to focus a light on the mirror, breath fogging up the mirror, the tongue and epiglottis getting in the way and the vocal cords are always moving.
Barely adequate exam
Traditionally, an ENT would place a mirror over their eye (or wear a head-light), then placce an angled mirror in the back of the throat and obtain a somewhat variable and fleeting view of the larynx. If the patient had no gag reflex, the view might even be somewhat prolonged. While large tumors, large nodules, a non-moving vocal cord, or other masses might be identified with this mirror, many things will be missed with a mirror.
The next level of exam is using a flexible fiberoptic endoscope passed through the nose and viewed with the naked eye. Although this exam can be performed for a longer period of time than a mirror exam - as it is less likely to cause gagging - the view is typically fuzzy because of the fiber-optic bundles and many things happen very rapidly on the vocal cords, faster than the eye can recognize.
Some of the problems with the above types of exams:
- The naked eye is a poor recording device.
- The images cannot be reviewed by the examiner a second time or by the patient or by a referring doctor.
- Changes in the vocal cords over time cannot be tracked.
- Many movements of the vocal cords happen too fast to see with the naked eye.
- Holding the mouth open with a mirror in the back of the throat alters the functioning of the larynx.
- There are no images to teach the patient about their problem.
Consequently:
- Looking in the mouth tells the examiner nothing about the vocal cords. The vocal cords are around a bend in the throat.
- A mirror in the throat provides a marginal exam.
- A flexible endoscope viewed with the eye, rather than with a camera and recording device, is also a barely adequate exam (at least if better options are available nearby).
Because of these issues, I consider these three types of exams inadequate or barely adequate, especially when the equipment to provide a minimal, but more detailed exam is so widely available, at least in the United States.
The patient in our story actually turned out to have a paralyzed vocal cord. Although her vocal cord partially recovered over time on its own - making the first doctor's advice seem to be correct when he said “just wait” - a more accurate exam would have gotten the patient quicker and perhaps more appropriate treatment.