basic diagnostic methods

Question 1

describe the examinations made in a lightened room?

Answer 1

1. examination of head, the peri ocular area, and the eye globe in a lightened room
2. preliminary ocular exams in a lightened room

Question 2

describe the normal eye globe?

Answer 2

both globes are the same size and shape; they are symmetrical, tightly undulating, and painless
Optical axes of the globes meet on an object which is seen

Question 3

list the preliminary ocular examinations in a lightened room?

Answer 3

1. PLR (pupillary light reflex)
2. Schirmer tear test (STT)
3. collection of specimens for lab tests
4. Evaluation of vision

Question 4

describe the PLR?

Answer 4

the reflex of the pupil in response to light striking the retina is termed pupillary light reflex
normal reaction = reaction of the pupil is symmetric with equal intensity

Question 5

describe the STT?

Answer 5

semi quantitative measurement of tear production
indicator for KCS
normal in dogs and cats = >14

Question 6

describe the tests used for evaluation of vision?

Answer 6

falling cotton test - the falling cotton is visually followed
obstacle test - negotiation of the obstacles is not visually impaired
menace reflex test - the animal is escaping by blinking and by bending of the head and neck from the threatening movement

Question 7

describe the normal palpebral fissures under detailed examination in a darkened room?

Answer 7

both are middle wide and symmetric, there is no discharge, there may be small, dried up clot of mucus at the medial canthus (sleep)

Question 8

describe the normal third eyelid under slit lamp examination?

Answer 8

it fits into the globe, only the free margin of the third eyelid can be seen at the medial canthus
free margin of the third eyelid can be pigmented
the palpebral surface is pale pink, smooth, moist shining, gently vascularised and has few to no lymphoid follicles
the bulbar surface is fresh red, velvet like and contains more, pale pink follicles

Question 9

describe the normal conjunctiva under slit lamp examination?

Answer 9

Pale pink, gently folded, covered by small amount of transparent tear, moistly shiny
discolouration can be seen
vascularisation normally difficult to see

Question 10

describe the positioning of the normal lacrimal puncta?

Answer 10

lower and upper located 1-3 mm from the medial canthus on the margin of the upper and lower lids

Question 11

shape of dogs lacrimal puncta?

Answer 11

rhomboid or drop like

Question 12

shape of normal cats lacrimal puncta?

Answer 12

rounded

Question 13

describe the normal cornea under slit lamp examination?

Answer 13

surface is uniformly glistening, images reflected are bright and sharp and regular in the centre, deformed at the periphery
the cornea is completely transparent and avascular
by gently touching the cornea with a small piece of cotton, the animal blinks

Question 14

describe the normal sclera under slit lamp examination?

Answer 14

only a small part is normally visible
surface is smooth, white, with no gaps or scarring
limbus may be pigmented

Question 15

describe the aqueous humour in the anterior chamber?

Answer 15

it is completely transparent and clear

Question 16

describe the abnormalities sometimes seen in the aqueous humour under slit lamp examination?

Answer 16

pus
blood
fibrin - Iris cyst, the lens, neoplasm

Question 17

describe the normal iris and pupil under slit lamp examination?

Answer 17

gentle circular pattern on its surface

the pupil is placed centrally

Question 18

describe the pupil of the horse, cow, and pig?

Answer 18

horizontal elliptical

Question 19

describe the pupil in dogs?

Answer 19

rounded

Question 20

describe the pupil in cats?

Answer 20

perpendicular rhomboid at middle wide position

Question 21

which species can have a corpora nigrum?

Answer 21

herbivores

Question 22

describe the normal lens under slit lamp examination?

Answer 22

purkinje images formed on the anterior and posterior lens capsule are bright, clear and regular
no opacity

Question 23

describe normal vitreous body findings with slit lamp examination?

Answer 23

vitreous is clear, there is no opacity inside

Question 24

name the staining techniques used for vital tissues?

Answer 24

1. fluorescein dye

2. Rose bengal

Question 25

describe the function of fluorescein dye?

Answer 25

stains defects in PTF or corneal epithelium bright green

Question 26

describe the function of Rose Bengal dye?

Answer 26

stains dead and degenerative cells brilliant red