Alignement

Alignement: 

Alignement Dr. Huseynova T.

Slide 2: 

s Primary Position

Classification: 

s Classification Orthophoria : The eyes are perfectly aligned, and no deviation occurs, even when the fusion reflex is disrupted. Heterophoria and Heterotropia : Misalignment compensated for by the fusion reflex keeps the deviation in heterophoria latent. Manifest misalignment is heterotropia . - Horizontal - Vertical - Torsional

Slide 4: 

s Determination There are four basic types of alignment tests which determine the alignement in a whole. The various cover tests The corneal reflex tests, The dissimilar image tests The dissimilar target tests.

Slide 5: 

s Determination Cover Test Which depend on the fixation reflex Advantages of cover testing include: a high degree of interobserver repeatability, easy quantification using prisms, and the ability to accurately measure the angle of deviation in all fields of gaze.

Slide 6: 

s Determination Cover Test

Slide 7: 

s Determination Cover Test Cover–uncover test

Slide 8: 

s Determination Cover Test Alternate cover test.

Slide 9: 

s Determination Corneal Reflex Test Studying the reflection of an examining light provides information regarding the alignment of the eyes in patients who cannot cooperate sufficiently to perform the alternate cover test or who lack fixation ability due to amblyopia . There are two kind of tests according to corneal reflex of the eyes: -- Hirshberg test -- Krimsky test

Slide 10: 

s Determination Corneal Reflex Test Hirschberg corneal reflex test Krimsky test

Slide 11: 

s Determination Corneal Reflex Test

Slide 12: 

s Determination Corneal Reflex Test Krimsky corneal reflex test. A. Congenital esotropic infant. B. Measuring esotropic angle.

Slide 13: 

Determination Dissimilar images test The same fixation target, which is simultaneously presented to each eye, is converted into dissimilar images on the right and the left retina for the purpose of making fusion difficult or impossible.

Slide 14: 

s Determination Dissimilar images test Maddox Wing Maddox Wing dissociates the eyes for near fixation (1/3m) and measures heterophoria . Measurements are made as follows: The horizontal deviation is measured by asking the patient to which number the white arrow points. The vertical deviation is measured by asking the patient which number the the red arrow interests. The amount of cyclophoria is determined by asking the patient to move the red arrow so that it is parallel with the horizontal row of numbers.

Slide 15: 

s Determination Dissimilar images test Maddox Wing Incyclo Excyclo Left Hypertrophy XF EF Right Hypertrophy

Slide 16: 

s Determination Dissimilar images test Maddox rod Maddox rod consists of a series of fused cylindrical red glass rod which convert the light into a red streak.

Slide 17: 

s Determination Dissimilar images test Maddox rod

Slide 18: 

s Determination Dissimilar images test Maddox rod Normal Xt Et

Slide 19: 

s Secondary Positions

Slide 20: 

s The three secondary positions are near fixation , cardinal positions , and midline position .

Near fixation: 

s Near fixation The purpose of investigating near fixation is to study the effect that the convergence associated with accommodation (synkinetic near reflex) has on the alignment of the eyes.

Near fixation: 

s Near fixation Determination The near point usually chosen to study the near alignment is 0.33 meter from the eyes. The test must be conducted so that the accommodation is stimulated. The only satisfactory tests for the near position are the cover test (cover–uncover, alternate cover, and simultaneous prism and cover). To stimulate accommodation, +3.00 lenses are inserted before each eye, simulating a test performed at 0.33 meter.

Near fixation: 

s Near fixation Classification The classifications of near fixation are as follows. Normal. The distant (primary position) and near position alignment are comparable. Abnormal. The distant and near position alignment are not comparable: - Convergence excess: greater esodeviation at near than at distance - Convergence insufficiency: greater exodeviation at near than at distance - Divergence excess: greater exodeviation at distance than at near - Divergence insufficiency: greater esodeviation at distance than at near

Slide 24: 

s Cardinal Positions Classification Normal. The horizontal and the vertical plane alignment are orthophoric in all six cardinal positions. Abnormal. There is a horizontal and/or a vertical plane misalignment in one or all of the six cardinal positions. Concomitant. The deviation is identical in all positions. Horizontal Esodeviation Exodeviation Vertical Right hyperdeviation Left hyperdeviation

Slide 25: 

s Cardinal Positions Classification Abnormal. There is a horizontal and/or a vertical plane misalignment in one or all of the six cardinal positions. Nonconcomitant. The deviation varies in different gaze positions. Horizontal Esodeviation Exodeviation Vertical Right hyperdeviation Left hyperdeviation

Slide 26: 

s Cardinal Positions

Slide 27: 

s Cardinal Positions The purpose of studying these six positions is to compare the prime mover of the one eye for each of these positions with the comparable prime mover of the other eye. (Only the horizontal and vertical planes are tested; the torsional plane is disregarded).

Slide 28: 

s Midline Positions Both horizontal and vertical plane deviations are studied in the up and down midline positions.

Slide 29: 

s Midline Positions Classification The classifications of midline positions are as follows: Normal. The horizontal and the vertical plane alignment are orthophoric in both straight upgaze and downgaze . Abnormal. A horizontal and/or a vertical plane misalignment is present in the upgaze position and/or the downgaze position. Horizontal A pattern V pattern

Slide 30: 

s Midline Positions Classification Abnormal. A horizontal and/or a vertical plane misalignment is present in the upgaze position and/or the downgaze position. Vertical Double elevator palsy Fibrosis of a vertical rectus muscle Myopathy due to thyroid disease Adherence syndrome - Following fracture of orbital floor - Following surgery of extraocular muscles - Brown syndrome (All these diseases will be presented in detail in the future presentations)

Slide 31: 

s Thank You