Medical & Surgical Ophthalmology

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Eye examination

The eye is a mirror of health and should never be considered separately as an organ, but rather as an organ that projects the general state of the body. Lesions in the eye are often the result of life-threatening pathological conditions, whether the eye is the primary cause of the disease or eye is the organ in which the systemic disease is manifested.

Also, even if the eye disease is not a life-threatening condition, the dog with vison issues or ocular pain, is not a happy dog. Such a pet will spend more time asleep, will be moody and inactive, and its daily activities will become hateful or possibly dangerous.

General eye examination

It is common for owners to be unaware of how much of a problem their pet has, until they visit an ophthalmologist. Only after the problem has been cured, then do you notice changes in your pet, you notice that it is more playful and that it has “rejuvenated”. For that reason, a detailed and professional general clinical examination of a dog or cat and a detailed and professional ophthalmological examination is necessary for a precise diagnosis and decision on therapy.

A detailed eye examination should include all or some of the following steps:

  1. Carefully taken medical history
  2. Ophthalmological examination
  3. Special diagnostic tests

Medical history

Each medical examination starts with detailed medical history. All information, including the breed, age, sex of the patient, previous medical history, information on current therapy or recent therapy, information on travel or change of residence as well as everything noticed by the owner regarding the general condition of the patient and/or changes in eye or eyes, or changes in the quality of the vision must be carefully documented.

Ophthalmological examination

The ophthalmological examination includes:

  • Examination of the eye by palpation and retropulsion
  • Evaluation the light reflex of the pupil
  • Evaluation of the palpebral reflex, which involves blinking after a tactile stimulus
  • Menace response – (examination of blinking reflex to the rapidly approaching of object)
  • Dazle reflex- (blink caused by strong focal light directed at the eye)
  • Schirmer test- test which determines the tear film quantity
  • Fluorescein test to determine the presence of corneal ulcers
  • Cannulation of the lacrimal system to evaluate its patency
  • Tonometry-test which evaluates the pressure within in the eye (intraocular pressure)
  • Conjunctival and corneal cytology and microbiology
  • Ophthalmoscope eye examination
  • Examination of the eye with a slit lamp
  • Electroretinography (ERG)
  • Ultrasound examination of the eye

If the additional evaluation of the vision is needed, the veterinary ophthalmologist will perform a “Maze test with obstacles” or a test with a cotton ball, as well as an electroretinogram and ultrasound examination of the eye, especially if the front segment of the eye is not transparent. An electroretinogram is necessary for us to diagnose diseases that can lead or have led to vision loss.

Special diagnostic tests

Many eye diseases are a repercussion of systemic diseases, so when an ophthalmologist suspects such conditions, he or she should check the patient’s complete blood count and biochemistry, determine the endocrine status, perform allergy tests or tests for the presence of infectious diseases. Sometimes, in order to make a diagnosis, it is necessary to perform cytological and microbiological examinations, sample tissues for histopathology evaluation, examine certain regions of the body with ultrasound, X-ray, computed tomography (CT scanner), magnetic resonance imaging and perform other necessary diagnostic tests.

Schirmer tear production test

Schirmer tear test determines the tear film quantity and includes the following tools and steps:

  1. Schirmer tear film quantity test strips (normal value for dogs is> 15 mm / min; normal value for cats is between 8 and 15 mm / min)
  2. Break the strip while it is still packed to avoid contamination of the strip with grease from the skin which can artificially change the test values
  3. Insert the tape into the fornix of the lower eyelid
  4. Close the eyelids for one minute, after which the production of tears can be read from the calibrated scale
general eye examination in cats
patient fixation
patient fixation French Bulldog

The photographs show patient fixation methods to ensure a safe clinical examination in aggressive patients

sirmer's tear test
opening the shirmer test bag
placing a sirmer test in the dog’s eye
sirmer test u oku psa

Tear production is evaluated with Schirmer test

Pupil reflex testing with chromatic light

eye reflex testing with chromatic light
Examination of the pupil reflex with chromatic light
Normal pupillary response after testing with chromatic red and blue light
Normal pupil response after testing with chromatic red and blue light
Retinal disease-chromatic light testing
Chromatic light response in the eye with retinal disease (negative response of the pupil when tested with red light, positive response of the pupil when tested with blue light)
Optic nerve disease - chromatic light testing
Chromatic light response in the eye with optic nerve disease (negative response of the pupil when tested with red light and blue light)

Tonometry- normal intraocular pressure in dogs and cats is within the range of 15-25 mmHg.
Examination of the eye with a slit lamp
Examination of the eye with a slit lamp

Examination of the dog with an indirect ophthalmoscope
Examination by indirect ophthalmoscope
Examination of the dog by gonioscopy
Examination of the dog by gonioscopy in order to determine the patency of the drainage angles of the anterior chamber and the predisposition for primary glaucoma

Examination of vision in a dog by testing the response
Examination of a dog's vision by testing the menace response
Maze test
"Maze" test

jones test
"jones" test

Jones test is used to detect obstruction of the nasolacrimal ducts. Fluorescein is placed in both eyes and a trace of fluorescein should appear from both nostrils within 5-10 minutes.

In the dog in the picture, we see that fluorescein appears from the right nostril, while the left one remained uncolored and dry, so we can conclude that for some reason the nasolacrimal system of the left eye is not patent

Nasolacrimal duct lavage
Flushing of the nasolacrimal duct for patency testing after application of a topical anesthetic
evaluation of the inner side of the third eyelid
Evaluation of the inner side of the third eyelid for the foreign bodies, parasitic organisms and enlarged lymphoid follicles after the application of a topical anesthetic

A dog with erosion on the cornea
A dog with corneal erosion that cannot be seen prior to staining with fluorescein
erosion of the cornea after staining
Corneal erosion that is easily detected after staining with fluorescein.

conjunctival sampling
Sterile sampling of the material from the surface of the conjunctiva for bacterial culture or PCR testing
Sampling for cytological analysis of Kimura spatula after application of topical anesthetic.
Sampling of the material with Kimura spatula for cytology evaluation after application of topical anesthetic

Examination of the dog by ultrasound biomicroscopy

Examination of the dog by ultrasound biomicroscopy

This technique allows a detailed examination of the anterior chamber of the eye and drainage structures for the aqueous humor, which can determine the predisposition for primary hereditary glaucoma, or detect the presence of tumors of the anterior part of the eye at a very early stage

ultrasound biomicroscopy
Examination of the dog by ultrasound biomicroscopy

The dog is under general anesthesia because it is prepared for the surgery, and the ultrasound examination is performed prior to surgery. Under other circumstances, neither general anesthesia nor sedation is necessary for this type of examination.

a modern examination of the optic nerve in a dog
Contemporary techniques of examination of the optic nerve in a patient with hereditary glaucoma - GDx and OCT analysis of the structure of the optic nerve
CT scan
Contemporary techniques of orbit and brain examination with mobile computed tomography (CT scan) in a patient with an orbital tumor. This type of diagnosis can also be used intraoperatively to confirm adequate resection of the mass