Prelim- Chapter 7 Primary Care Flashcards
Also known as “squint” or “strabismus”
Tropia
Purpose of Preliminary examination
to detect any gross anomaly such as:
high refractive error
binocular vision anomaly
disturbance of ocular motility
ocular or systemic diseases.
Order of ocular examinations
- Visual Acuity
- Tests of ocular motility and binocular vision
- Tests of Color Vision
- Visual Field screening
a. Confrontations - Tonometry
- Blood Pressure measurement
- External examination (anterior segment Evaluation)
a. Slit lamp examinations - Internal examination (Posterior Segment Evaluation)
a. Fundus Evaluation
i.Direct
il.Indirect
Special Investigations:
A-scan
Ultrasound (B-scan)
Perimetry
Pachymetry
Goniosopy
Ocular photodocumentation
Fundud Fluorescein Angiography
Contrast Sensitivity Test
Amsler grid Testing
Electrodiagnostic tests
Neurodiagnostic tests
Keratometry
Exophthalmometry
Ophthalmodynamometry-for carotid artery insufficiency; transient loss of vision
is assessed to obtain visual status of each eye.
Visual acuity
helps differentiating abnormality due to dioptric apparatus or one due to organic disease.
Pinhole test
Defect in dioptric apparatus is further confirmed by___.
retinoscopy
VA charts
Snellen’s test types
E test chart
Landolt’s broken ring test types.
SG chart
kay picture cards
Optokinetic nystagmus test
forced preferential looking charts
LogMAR charts
• It is recommended that you stand back and observe the whole patient for a few seconds before carrying out the examination.
Sometimes, observation alone is sufficient to give you the diagnosis and the examination only serves to confirm it.
• Observation is conducted for Head posture, facial asymmetry, Forehead, Eyebrows, ocular posture, ocular movements
General observation
Determined by the position of the two visual axes in the primary position of gaze.
Ocular posture
position of light reflex is seen by asking the patient to see on the torch light. Reflex on the temporal side of pupil indicates the eye is convergent & if it is on the nasal side the eye is divergent.
Hirchberg test:
ask patient to focus on a near target and follow it as she traces a broad letter “H.” This tests the ability of the e yes to follow the target. It will indicate any problem with th e nerve supply to the eye muscles or problems with the m uscles themselves.
Ocular motility
Done either in
• Diffused light using torch Or Focal illumination using slit lamp or loupe.
• Procedures go as follows:
Asymmetry in wrinkling of foreheads
Eyebrows
Eye lashes
Eye lids
Conjunctiva
Method of examination
Bulbar coniunctiva is examined by retracting the upper lid & lower lid by index finger & thumb respectively.
• Lower palpebral conjunctiva is seen by asking the patient to look up & then pulling the lower lid down.
• Upper palpebral conjunctiva & fornix is seen by asking the patient to look down and then grasping the lid margin by thumb & index finger the lid is everted using index finger as fulcrum.
External ocular examination
• Points to be noted while doing external examination
• Redness or congestion.
• Discharge.
• discoloration.
• Chemosis.
• Changes on the surface.
• New formations: papillae, follicles, concretions, pinguecula, pterygium, phlycten, tumors, cysts etc.
• Ulcers & granulomas.
• Membranes & pseudomembranes.
• Scar
• Foreign bodies.
Examination of sclera:
• The white sclera is visible through conjunctiva.
• The points to be noted are:
Colour
Congestion.
Pain & tenderness.
Traumatic perforations.
Examination of cornea
t should be done under slit lamp examination.
• The points to be noted are
Size: normal cornea is 11 mm vertically & 11.7 mm horizontallv.
• Curvature
• Surface is also assessed using placido’s keratoscopic disc. Other tests for topography are photokeratoscopes.
Transparency
Opacity
• Foreign bodies
Abrasions
Ulcerations
• Vascularization
• Corneal sensations
• Corneal endothelium examination using specular microscopy.
• Corneal thickness (using pachymetry) estimation.
Corneal staining is performed when epithelial defect is suspected.
In this flourescense strip is placed in the inferior fornix. Patient is asked to blink and then cornea is inspected under cobalt blue light.
Cornea is translucent, smooth and avascular.
Examination of anterior chamber
• It’s done best under slit lamp.
•Depth and contents are noted.
• Normally anterior chamber is clear with aqueous humor.
• Following contents in the AC are noted:
• Hyphaema
• Hypopyon
Aqueous flare & cells
• Lens
• Lens particles
Examination of Iris
•Normally iris is flat & color varies
• Things to be noted if present
• Adhesions (synaechiae)
• tremulousness (iridodonesis)
• new vessel formation
• pupillary membranes
• Colobomas
• prolapse
• irridodialysis
• nodules
• Cysts
Ocular motility and binocular vision
a. Cover Tests
b. Corneal Reflex Tests
c. NPC Testing
d. NPA Testing
e. Motility Tests
F. Tests of Pupillary function
g. Tests of stereopsis
Different ocular postures are:
esotropia
exotropia
hypotropia
hypertropia
Incyclotropia
excyclotropia.
It is revealed by cover-uncover test.
_____ is done by covering one eye and watching the other eve for a fixation movement. Uncover test is done by watching they eye just uncovered.
Cover test
can be used to test visual acuity for preschool children who have not yet learned the alphabet. As an assistant points out the pictures, beginning with the birthday cake at the top of the chart, the child is asked to name, or describe, the picture or pictures in each row.
The Birthday Coke project-o-chart
For children between the ages of about 3 and 6 years who cannot recogntze enough letters to make the use of a standard letter chart,
The child is given a wooden or plastic letter E and instructed to point the “legs” of the E in the same direction as those of the E on the chart.
The Tumbling E Chart.
is an alternative to the tumbling E chart. The examiner states that “somebody has taken a bite out of this doughnut and asks the point at the part of the donut that is missing
The landolt C chart
consists of a set of seven cards, each containing a single picture, and can be used for children 2 years of age and older. The child is first shown the cards at close range, with both eyes open, and is asked to name each picture (the names in many cases will differ from the names an adult would be expected to use). One eye is then occluded, and the examiner shuffles the cards–using the cards that appear to have the most meaning for the child and presents them individually at increasingly greater distances.
The Allen preschool vision test
consists of letter charts designed for use at 10- and 20-foot distances together with sets of miniature eating utensils and a number of toys.
The child is given a large card, called a key card, and is asked to fod the letter on the card that is the same as the letter on the distance chart. The eating utensil set includes a small set of utensils held by the examiner (first at 10 feet and then at 20 feet) and a large set held by the child.
The STYCAR (Screening lest for Young Children and Retardates) visual acuity test
Like the STYCAR test, provides a large key card for use by the child. The child is asked to point to the letter on the key card that is the same as the letter shown on the distance chart
The distance chart is in the form of a spiral-bound booklet, with one letter presented on each page. The Sheridan-Gardiner test also includes a reduced Snellen chart for near testing.
The Sheridan-Gardiner visual aculty test
have a “lap card” that the child holds and a visual acuity chart at 10 or
20 ft.
Contrary to many reports still in optometric literature, a 3-year-old child should be expected to have visual acuity of approximately 20/20.
The HOTV letter chart and the Lea symbols,
also called the cover-uncover test
Unilateral cover test
the practitioner can determine the presence or absence of a tropia also known as strabismus, or squint.
And by means of the alternating cover test, he or she can determine whether a phoria or a tropia is present but cannot differentiate between the two. If the unilateral cover test results in a negative finding, a positive finding on the alternating cover test indicates the presence of a phoria.
Because the______ can interfere with the manifestation of a tropia, it is customary to perform the unilateral cover test first.
alternating cover test
The Unilateral Cover Test
While wearing his or her own spectacle correction, if any, the patient’s attention is called to a letter on the 6-m Snellen chart.
To ensure that accommodation is relaxed, the letter should be no larger than one line above the patient’s corrected acuity with the worse eye, and the patient should be instructed to keep the letter in sharp focus. The practitioner is seated opposite the patient, with his or her head positioned so that it does not block the patient’s view of the chart. Sufficient illumination must be directed toward the patient’s eyes so that the practitioner can observe any eye movement
A tropia may be present at some times and not at others; this is an_____ tropia.
For example, a patient who has intermittent exotropia may be found on one occasion to have right exotropia but on the next occasion to have only a high exophoria.
intermittent
If a tropia is found at one testing distance but not at another, the condition is called ____ .
For example, in some cases of accommodative esotropia, the patient may have no strabismus at distance but may have esotropia at near testing, while in divergence excess, there may be no strabisinus at near but exotropia may he found on distance testing.
Periodic tropia/strabismus.