Endoscopy
An endoscope is made of hundreds of small flexible glass fibres in a long plastic tube. It can be used to look up a horse’s nose, down the windpipe or oesophagus, or up the urethra or vagina. The sort of problems that we can investigate using a “scope” are:
A discharge from the nose: The endoscope lets us see where the discharge is coming from, such as the sinuses, guttural pouches or the lungs. Sometimes we bore a hole into a sinus from the outside and use the endoscope to look at tooth roots or identify other diseases within the sinuses.
Whistling, roaring and other abnormal respiratory noises: These may caused by an abnormality of the larynx, pharynx, soft palate or epiglottis. The endoscope lets us look at these structures, and anything is abnormal we can decide what sort of surgery is required to correct the problem.
Persistent choke: in most horses choke is simply due to inappropriate eating of food and clears with treatment, but in some animals there is a problem with the function of the oesophagus.
Lung problems: Many horses have allergic airway disease (COPD or chronic obstructive pulmonary disease) due to exposure to fungal spores from hay or straw. A few horses develop chronic lung infections. Both of these conditions can be diagnosed by looking down the windpipe and by taking a sample of the mucus and cells which pool down there (a tracheal wash).
Bladder problems: such as stones are uncommon, but if a horse has blood in the urine or difficulty passing urine this can help to make a diagnosis.
Uterine problems: on occasions the endoscope can be useful to identify some abnormalities of the uterus.
We like to endoscope horses at the clinic if possible because it is an expensive piece of equipment and is less likely to get damaged, because we have access to other items of equipment, and because we can analyse samples as soon as possible. Most horses tolerate the endoscope well, but occasionally they will need to be sedated.