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BLOCK 1: Clinical Exams

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BLOCK 1: Clinical Exams Theme 1: Case History Theme 2: Material Theme 3: Visual Acuity Theme 4: Retinoscopy Theme 5: Subjective Theme 6: Covert Test – PowerPoint PPT presentation

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Title: BLOCK 1: Clinical Exams


1
BLOCK 1 Clinical Exams
  • Theme 1 Case History
  • Theme 2 Material
  • Theme 3 Visual Acuity
  • Theme 4 Retinoscopy
  • Theme 5 Subjective
  • Theme 6 Covert Test
  • Theme 7 Accomodation

2
Theme 4 Retinoscopy
4
  • Utility

5
  • Material
  • Method

9
Previous conditions
10
Retinoscopic observations
10
Description
Analysis parameters
12
3
Theme 4 Retinoscopy
  • Method

Technique
General mechanics
26
Examples
31
Emmetropia
34
Spherical ametropia
Astigmatic ametropia
39
  • Self-evaluation

48
  • Bibliography

59
4
Utility
The static retinoscopy is an objective technique
that provides the value of the refraction in
distance vision.
Utility
the analysis of the reflection of light that is
obtained upon projection of a ray of light onto
the patients pupil.
It is based on
5
Material
Lenses
Support
Test of visual acuity
Retinoscopy / Skiascopy
6
Material
Retinoscope
Optotype for dynamic retinoscopy
Flat mirror (?)
Concave mirror (?)
7
Method
There are diverse retinoscopic techniques
Accomodation does not take part. The subject
observes an optotype for distance vision and the
fogging technique is relied upon to relax
accomodation.
  • Static

Realized with near vision. There are many
techniques Cross, Mohindra, etc.
  • Dynamic

In this chapter we only address the static.
8
Method
1. Previous conditions
2. Retinoscopic observations
2.1. Description
2.2. Analysis parameters
3. Technique
3.1. General mechanics general
3.2. Examples
9
Method
1. Previous conditions
Light
It can be more comfortable to perform it in faint
light. A pupil of greater size and less
reflection appears.
Graduation
The patient will have both eyes open and wil be
without his/her graduation, (to the contrary, we
would be doing one with graduation).
Myopization
In order to control accomodation, it is a good
idea to start with a fogging around 0,3-0,4.
10
Method
2. Retinoscopic observations
2.1. Description
Mirror of the retinoscope
Object of study
Sclera
Retinoscopic reflection
Pupil
Iris
11
Method
2. Retinoscopic observation
The retinoscopic reflection is analyzed with
respect to the mirror and the result of this
analysis will provide us with information on the
type and quantity of Any existing ametropia.
  • The type of movement
  • Parallelism

The parameters of analysis are
  • The width of the reflection

12
Method
2. Retinoscopic observation
2.2. The Parameters of analysis
Mirror of the retinoscope
  • The type of movement
  • Parallelism
  • The width of the reflection

Retinoscopic reflection
13
Method
2. Retinoscopic observation
2.2. The parameters of analysis
  • The type of movement

With Movement (WM)
Mirror and reflection go in the same direction
Against Movement (AM)
Mirror and reflections go in opposite directions
14
Method
2. Retinoscopic observation
2.2. The parameters of analysis
  • The type of movement

Upon moving the retinscopic mirror, depending on
the type of ametropia and the mirror used, we
will observe whether the retinoscopic reflection
moves in the same or the opposite direction as
the mirror.
Selection of the mirror
15
Method
2. Retinoscopic observation
2.2. The parameters of analysis
  • The type of movement

Hypermetropia
Myopia
With Movement
Against Movement
Flat mirror
Against Movement
With Movement
Concave mirror
Correction with positive lens
Correction with negative lens
Supposing the working distance has been
compensated for
16
Method
2. Retinoscopic observation
2.2. The parameters of analysis
Mirror of the retinoscope
  • The type of movement
  • Parallelism
  • The width of the reflection

Retinoscopic reflection
17
Method
2. Retinoscopic observation
2.2. The parameters of analysis
  • Parallelism
  • It refers to the parallelism between the mirror
    of the retinoscope and that pertaining to the
    retinoscopic reflection.

Mirror of the retinoscope
Retinoscopic reflection
Not parallel
Parallel
18
Method
2. Retinoscopic observation
2.2. The parameters of analysis
  • Parallelism
  • If when turning 360º there is parallelism

spherical ametropia
Mirror of the retinoscope
Spherical ametropia
Retinoscopic reflection
Parallel
Parallel
19
Method
2. Retinoscopic observation
2.2. The parameters of analysis
  • Parallelism
  • The lack of parallelism indicates

Astigmatic ametropia
Faced with this situation, the principal
meridians must be looked for. Said meridians are
found in the direction where said parallelism
appears.
Mirror of the retinosccope
Retinoscopic reflection
Not parallel
20
Method
2. Retinoscopic observation
2.2. The parameters of analysis
  • Parallelism

The retinoscopic mirror will be turned until the
degrees in which parallelism appears between the
mirror and the retinoscopic reflection are found.
Mirror of the retinoscope
The track of the direction provides us with the
retinoscopic reflection.
Retinoscopic reflection
Not parallel
21
Method
2. Retinoscopic observation
2.2. The parameters of analysis
  • Parallelism

60º
150º
Mirror of the retinoscope
Retinoscopic reflection
Parallel
Parallel
Not parallel
Principal meridians (Perpendicular)
22
Method
2. Retinoscopic observation
2.2. The parameters of analysis
  • Parallelism

It is important to determine the existence of the
principal meridians since the neutral point of
the retinoscopic reflection must be realized
according to them.
Once the meridians are determined, the mirror
will be analyzed for the parameters of width and
the type of movement in order to try to achieve
the neutral point.
23
Method
2. Retinoscopic observation
2.2. The parameters of analysis
Mirror of the retinoscope
  • The type of movement
  • Parallelism
  • The width of the reflection

Retinoscopic reflection
24
Method
2. Retinoscopic observation
2.2. The parameters of analysis
  • Width of the reflection (EP)

The width of the retinoscopic reflection is the
streak of light reflected that occupies the
pupil, totally or partially. This occupied
space provides information on the quantity of
ametropia.
The sensation of occupation (width), will be
determined by the pupillary diameter and by the
level of ametropia.
25
Method
2. Retinocopic observation
2.2. The parameters analysis
  • The width of reflection (EP)

With respect to the level of ametropia, if we
evaluate the width, the reflection occupies more
space in
- Elevated ametropias
Accompanied by a dull reflection
Accompanied by a more luminous reflection
- Near the neutral point
26
Method
3. Technique
3.1. General mechanics (static RT)
  1. Cover RE and fog the patient LE to VA 0,3-0,4
  2. Uncover RE and place the lens corresponding to
    the work distance (WD) in front (for example 50
    cm. corresponds to 2,00D).
  3. Indicate to the patient that he/she will see the
    test in DV (VA 0,3-0,4)
  4. Observe the reflection of the patients RE with
    the examiners RE.
  5. Analyze and neutralize the retinoscopic
    reflection
  6. Leave the gross value (settting aside the lens
    that corresponds to the WD situation of fogging)
    and move on to observe the LE

Retinoscopy RE
27
Method
3. Technique
3.1. General mechanics (static RT)
  1. With the RE the optotype for DV was observed (it
    is fogged when setting aside the retinoscopic
    lens).
  2. Place a lens corresponding to the work distance
    in front of the LE
  3. Observe the patients LE with the examiners LE.
  4. Analyze and neutralize the retinoscopic
    reflection.

Retinoscopy LE
(During the realization of the test, we must
insist that the patient continues looking at the
optotype for DV).
28
Method
3. Technique
3.1. General mechanics (static RT)
Upon finishing this process we find that the
subject has, placed in front of him/her, the
lenses
- corresponding to the work distance (WD)
Gross value
Net value
- corresponding to the refractive defect
29
Method
3. Technique
3.2. Examples
Next, the observation and neutralization of
diverse ametropic situations are going to be
described.
Retinoscopic reflection (pupil)
Sclera
2.00
Lens compensating for work distance
streak of light of the retinoscope
30
Method
3. Technique
3.2. Examples
The type of movement
Flat Mirror (FM)
Paraneters
Parallelism
Description of the observations
The width of the reflection
Summary of the Observation
Neutralization
Action to realize
Lens
Value of the refractive correction (Net value of
the retinoscopy)
31
Method
3. Technique
3.2. Examples
1. Emmetrope eye
2. Spherical ametropia
3. Astigmatic ametropia
32
Method
3. Technique
3.2. Examples
1. Emmetrope eye
The type of movement
Flat mirror (FM) Without movement
Concave mirror (CM) Without movement
Parameters
Parallelism
The streak of light is not observed in the
retinoscopic reflection
The width of the reflection
It fills the pupil in what is known as NEUTRAL
POINT (NP), point of neutralization
33
Method
3. Technique
3.2. Examples
1. Emmetrope eye
2.00
Summary of the observation
Neutral point. All of the pupil illuminated,
there is no streak of light with either of the
mirrors
Neutralization
Lens
There is no precise lens to neutralize
Value of the refractive correction
Neutral
34
Method
3. Technique
3.2. Examples
1. Emmetrope eye
Hypermetropia of 3,00 D
2. Spherical ametropia
Myopia of - 3,00 D
3. Astigmatic ametropia
35
Method
3. Technique
3.2. Examples
2. Spherical ametropia HP 3,00D
(Observation with FM)
The type of movement
Flat Mirror (FM) With
Concave Mirror (CM) Against
Parameters
Parallelism
Parallelism in 360º
The width of the refraction
Intermediate
36
Method
3. Technique
3.2. Examples
2. Spherical ametropia Hp 3,00D
(Observation with FM)
Summary of the Observation
With movement with FM. A streak of light of
intermediate width is observed, parallel to the
streak of light of the retinoscope in 360º
Neutralization
Lens
Positive lenses are put in front of the subject
until neutral point is achieved.
3,00 D
Value of the refractive correction
37
Method
3. Technique
3.2. Examples
3. Spherical ametropia Mp - 3,00D
(Observation with FM)
The type of movement
Flat Mirror (FM) Against
Concave Mirror (CM) With
Parameters
Parallelism
Parallelism in 360º
The width of the reflection
Intermediate
38
Method
3. Technique
3.2. Examples
3. Spherical ametropia Mp - 3,00D
(Observation with FM)
Summary of the observation
Against movement with FM. A streak of light of
intermediate width is observed, parallel to the
streak of light of the retinoscope in 360º
Neutralization
Lente
Negative lenses are placed in front of the
subject until neutral point is achieved
- 3,00 D
Value of the refractive correction
39
Method
3. Technique
3.2. Examples
1. Emmetrope eye
2. Spherical ametropia
-3 ,00D 180º
3. Astigmatic ametropia
-3 ,00D 90º
40
Method
3. Technique
3.2. Examples
2. Astigmatism - 3,00D 180º
(Observation with FM)
Vertical retinoscopic streak of light Does not
exist
The type of movement
Flat Mirror (FM)
Parameters
Horizontal retinoscopic streak of light Against
41
Method
3. Technique
3.2. Examples
2. Astigmatism - 3,00D 180º
(Observation with FM)
Parallelism
Retinoscopic streak of light at
Parameters
90º
When there is not a streak of light of the
reflection parallelism is not determined
45º
There is no parallelism, we are not along any of
the main meridians
There is parallelism between the streak of
lightS. We are along the ametrope meridian
180º
42
Method
3. Technique
3.2. Examples
2. Astigmatism - 3,00D 180º
(Observation with FM)
Summary of the observation
Against movement with the FM with retinocscopic
streak of light at 180º. Neutral point with FM
with retinoscopic streak of light at 90º.
Neutralization
Place negative lenses in front of the subject
until neutralization of movement is achieved. If
an astigmatic lens is used the axis will be in
the same direction as the Movement.
Lens
Value of the refractive correction
- 3,00 180º
43
Method
3. Technique
3.2. Examples
Summary - 3,00D 180º
(Observation with FM)
Neutral point
Against movement (streak of light parallel)
Increase negative cylinder with the horizontal
axis until movement is neutralized
RE 0,00 - 3,00 180º
Value of the refractive correction
44
Method
3. Technique
3.2. Examples
2. Astigmatism - 3,00D 90º
(Observation with FM)
Vertical retinoscopic streak of light Against
The type of movement
Flat Mirror (FM)
Parameters
Horizontal retinoscopic streak of light Does not
exist (neutral point)
45
Method
3.Technique
3.2. Examples
2. Astigmatism - 3,00D 90º
(Observation with FM)
Parallelism
Retinoscopic streak of light at
Parameters
90º
There is parallelism between streak of light. We
are along the ametropic meridian.
45º
Thre is no parallelism, we are not along any of
the meridians.
180º
When there is no existing streak of light of the
relfection parallelism is not determined.
46
Method
3. Technique
3.2. Example
2. Astigmatism - 3,00D 90º
(Observationswith FM)
Summary of the observation
Against movement with FM with retinoscopic streak
of light at 90º. Neutral point with FM with
retinoscopic streak of light at 180º.
Neutralization
Place negative lenses in front of the subject
until neturalization of movement is achieved. If
an astigmatic lens is used the axis will be in
the same direction as the movement.
Lens
RE - 3,00 90º
Value of the refractive correction
47
Method
3. Technique
3.2. Examples
Summary - 3,00D 90º
(Observations with FM)
Neutral point
Against movement (Parallel streak of light)
Increase the negative cylinder with the vertical
axis until neutralization of movement has
achieved.
RE 0,00 - 3,00 90º
Value of the refractive correction
48
Exercises
Self-evaluation
49
Exercises
Exercise 1
Methodology
Exercise 2
Spherical ametropia
Exercise 3
Astigmatic ametropia
Exercise 4
Astigmatic ametropia
50
Exercises
Exercise 1
Indicate the best option with regards to the
methodology of the static retinoscopy
a. At a distance of 1m., the corresponding
working lens is of 2,00 D
b. If we realize the retinoscopy to the left eye,
the right has to be covered
c. If after placing the lens corresponding to the
work distance in front of the subject we observe
against movement along all meridians with the
flat mirror, the streak of light is wide, not
very bright and slow, we are faced with a low
myopia.
d. When realizing the retinoscopy on the right
eye, the left eye must be foggedd and using
distance vision.
51
Exercises
Exercise 1
Indicate the best option with regards to the
methodology of the static retinoscopy
a. At a distance of 1m., the corresponding
working lens is of 2,00 D
b. If we realize the retinoscopy to the left eye,
the right has to be covered
c. If after placing the lens corresponding to the
work distance in front of the subject we observe
against movement along all meridians with the
flat mirror, the streak of light is wide, not
very bright and slow, we are faced with a low
myopia.
d. When realizing the retinoscopy on the right
eye, the left eye must be fogged and using
distance vision.
52
Exercises
Exercise 2
If when doing the retinoscopy and after putting
the lens that neutralizes the work distance in
front of the subject, we find ourselves with the
following observation (FM), indicate which lens
will most probably lead us to neutralization
a.
Observation
Options for neutralization
b.
c.
53
Exercises
Exercise 2
If when doing the retinoscopy and after putting
the lens that neutralizes the work distance in
front of the subject, we find ourselves with the
following observation (FM), indicate which lens
will most probably lead us to neutralization
Observation
c.
Options for neutralization
54
Exercises
Exercise 3
If when doing the retinoscopy and putting the
lens that neutralizes the working distance in
front of the subject, we find ourselves with the
following observation (FM), indicate the
combination of lenses that will most probably
lead us to neutralization
a.

Observation
Options for neutralization
b.

c.

55
Exercises
Exercise 3
If when doing the retinoscopy and putting the
lens that neutralizes the working distance in
front of the subject, we find ourselves with the
following observation (FM), indicate the
combination of lenses that will most probably
lead us to neutralization
Observation
a.
Options for neutralization

56
Exercises
Exercise 4
If when doing the retinoscopy and putting the
lens that neutralizes the working distance in
front of the subject, we find ourselves with the
following observation (FM), indicate the
combination of lenses that will most probably
lead us to neutralization
a.
b.
Observation
Options for neutralization
c.

57
Ejercicios
Ejercicio 4
If when doing the retinoscopy and putting the
lens that neutralizes the working distance in
front of the subject, we find ourselves with the
following observation (FM), indicate the
combination of lenses that will most probably
lead us to neutralization
Observation
c.

Options for neutralization
58
Bibliography
59
Bibliography
  • Borràs MR et al. Optometría. Manual de exámenes
    clínicos.
  • Barcelona Edicions UPC, 1993
  • Borish IM, Benjamin WJ(ed.). Borish's clinical
    refraction.
  • Philadelphia W. B. Saunders, 1998
  • Grosvenor TP. Optometría de atención primaria.
  • Barcelona Masson, 2004
  • Carlson NB et al. Procedimientos Clínicos en el
    examen visual.
  • Madrid Ciagami, 1994
  • Herreman R. Manual de refractometría clínica.
  • México Ediciones Salvat, 1981
  • www

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