more than 75% of persons older than 75 years have lens opacitiess

1
??????? ???????? ?????

• ? . ???? ????????

2
more than 75 of persons older than 75 years
have lens opacitiess
3
(No Transcript)
4
(No Transcript)
5
???? ?? 75 ?? ??????? ???????? ?? 75 ??? ??????
??????? ?? ??????
6

• A cataract is commonly defined as any opacity in
  the ocular lens

7
???? ????? ???? ?? ????? ?? ??????
8
AGE-RELATED CATARACT (SENILE CATARACT)
9
????? ??????? ?????? (????? ??????)
10
Constantius Africanus of the Monte Cassino
Monastery translated the ancient Arabic
manuscripts into medieval Latin and applied the
word cataracta, meaning "to rush down, as a
waterfall
11
???? ??????? ???????? ???? ???? ?????" ??
??????? ?????? ?????? ??? ????????? ?????
cataracta??? ???? ?????? ?????? ???????
12

• When biochemical or physicochemical changes
  develop that disrupt the architecture or result
  in formation of molecules larger than 1,000 nm
  (10,000 A )

13
???? ????? ????? ???? ???????? ??????? ??????????
???????? ???????? ??? ???? ?????? ???? ?? 1000
????????
14

• ???? ???? ???????? ??????? ??? ?????? ??????????
  ?? ??????? ??????

15
Immature, mature, and hypermature (i.e.,
increasing degrees of cataract "maturity")
Incipient (i.e., early) Sclerotic (i.e., hard)
Minimal, moderate, and advanced (i.e.,
increasing degrees of aggregate quantity of
cataract)

16
?????? ??????? ????? ??????? ?? ???? ???? ?????
17
??? ???? ???? ???? ????? ? ????Incipient??????
Sclerotic? ???? ?????? ?????? Minimal, moderate,
and advanced
18

• pure anatomic types (cortical, nuclear, and
  posterior subcapsular) and mixed types
  (combinations of these three).

19
????? ??????? ???????? ????? ????? ????? ??????
???? ????? ???? ??????
Classification schemes such as the Lens
Opacities Classification System II and III (LOCS
II and LOCS III),
20

• standard grades as set up in the various
  classification schemes (clinical grading), or one
  may take photographs of the lens being studied
  and later grade the photographs according to the
  classification scheme used (photographic grading)

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• Cortical cataracts are the most common of the
  three major pure cataract types..

23
????? ?????? ?? ?????? ?????? ??? ??????? ???????
24

• It is notable that although certain types of
  cataracts may initially occur as pure types, as
  the cataract progresses, it eventually becomes
  mixed as the other anatomic areas also become
  affected

25
???? ??????? ??????? ???? ?? ????? ????? ??????
???? ?????? ??????? ??????
26

• The cortical layer is approximately 2 mm for
  both anterior and posterior layers in the adult
  and is metabolically active

27
????? ????? 2 ?? ??? ???? ????????? ??? ??????
28

• new cortical fibers are continuously laid down
  by the bow region cells. The cortical layer is
  less compact than the nucleus and is therefore
  more prone to becoming overhydrated as a result
  of electrolyte imbalance, which eventually leads
  to disruption of the lens cortical fibers

29
????? ????? ????? ??? ????? ????????? ??? ???
????? ?? ?????? ????? ???? ???? ??????? ??? ????
?????? ????? ????? ? ??? ???? ??? ???? ?????
??????
30

• Early changes may include signs such as vacuoles,
  water clefts, and lamellar separation .These
  changes may come and go over time, but eventually
  they may predispose the patient to damage and
  irreversible opacification of some fibers.

31
???????? ??????? ?? ?????? ????? ????? ???????
????? ????? ? ? ?? ???? ?? ???? ?????? ???? ?????
???? ??? ????? ??????? ???? ???? ??? ???????
???????
32

• The resulting opacity, however, needs to be
  located at or near the visual axis for it to
  affect vision and become clinically important

33
???? ?? ???? ??????? ??????? ????? ???
???????????? ?? ???? ?? ???? ??? ??????
34
CORTICAL CATARACTS Cortical cataracts are the
most common of the three major pure cataract
types it eventually becomes mixed as the other
anatomic areas also become affected.
35
????? ?????? ?? ????? ?????? ?????? ??? ?????
????? ???????? ???????? ??? ????? ????? ??????
??????? ?? ????? ?????? ??? ????? ??????? ?????? .
36
Recent studies also suggest the possible role of
an abnormality of the maturation process of the
lens fibers with subsequent poor development of
primary, secondary, and tertiary sutures in the
formation of cortical cataracts
37
???? ?????? ??? ??? ?????? ?? ????? ??? ?????
?????? ? ???? ??? ??? ?? ????? ?? ?????? ????????
38
It has therefore been proposed that this type of
cataract may be partly caused by osmotic stress.
Early changes may include signs such as vacuoles,
water clefts, and lamellar separation). These
changes may come and go over time, but eventually
they may predispose the patient to damage and
irreversible opacification of some fibers.
39
????? ?? ???? ?????? ??????? ????? . ?????
???????? ??????? ?? ???? ?????? ????? ????? ?
???? ????? ??????????? ??? ???????? ??? ?????
?????? ???? ????? ?? ?????
40
opacities also develop in the periphery in other
quadrants, resulting in a circular array of
spokes and peripheral cuneiform opacities
41
???? ?????? ?? ?????? ?? ????? ?????? ???????
?????? ???? ?? ??? ?????? ????? ???? ?? ????????
???????? ?? ??? ??????
42
(No Transcript)
43
Cortical opacities have been clinically observed
to develop earliest in the inferior half of the
lens, especially the lower nasal quadrant.
44
????? ??????? ??????? ?? ????? ?????? ???????
?????? ????
45
may also be caused by ultraviolet rays from
sunlight ,the supraorbital margins may block the
ultraviolet rays from falling over the upper part
of the lens
46
???? ?? ????? ???? ?????? ??? ????????? ??????? ?
????? ???? ?????? ??????? ????? ????? ?????? ??
??????
47
Most cortical cataracts, however, remain in the
periphery for many years, even decades, before
the central axis of the lens becomes involved,
causing loss of vision
48
???? ?????? ????? ?? ????? ??????? ??? ???? ???
?????? ??????? ??? ??? ?????? ??????
49
however, these patients have severe disability
glare as documented by the Brightness Acuity
Meter (BAT) ,such that under simulated bright
lights, their visual acuity may decrease to 20/80
or worse. They also have decreased contrast
sensitivity. These patients tend to do well
indoors but have difficulty driving during
bright, sunny days and at night because of
oncoming headlights.
50
?? ?????? ?????? ?? ??????? ?? ?????? ? ?????
?????? ?? ????? ?? ?????? ??????? ??? ?????
???????? ???? ??? ????? ?? ??????? ????? ??????
51
This type of cataract is best seen with
retroillumination, which gives an enhanced
picture of the cortical spokes and vacuoles by
the shadows they cast as the light is reflected
back by the fundus. Direct illumination helps
clarify the level of the opacities
52
??? ????? ???? ???????? ??????? ??????? ? ?????
??????? ???????? ?? ??????? ???? ???????
53
NUCLEAR CATARACTS
54
????? ??????
55
Nuclear cataracts appear to be an exaggeration of
the normal sclerosis or hardening and yellowing
of the nucleus in older adult patients
56
????? ?????? ???? ?????? ?? ???? ??????? ??????
???? ???? ??? ?????? ?????? ???
57
tend to progress slowly
58
???? ??? ?????? ????
59
usually resulting in increasing myopia
60
???? ??? ????? ?????
61
accompanied by optical distortion, especially of
distant images, while near vision remains ,
62
?????? ??????? ????? ???? ?? ?????? ??????? ?
????? ???? ?????? ??????? ????
63
potential acuity testing with the potential
acuity meter or laser interferometer is very
helpful in determining whether the poor vision is
due to myopic.
64
??? ?????? ??????? ??????? ?????? ?????? ???????
??????? ???? ?? ????? ??? ??? ????? ???? ????? ??
???? ???????? ?????
65
Christmas tree" cataract
66
????? ???? ???? ??? ???????
67
Later, the entire nucleus appears as a
homogeneous mass in contrast to the cortex
.Retroillumination may show the "oil droplet"
effect
68
???? ?????? ?????? ???? ???? ????? ,?????? ????
???? ?????
69
Nuclear cataracts are associated with
physiochemical changes in the lens structural
proteins (a-, b-, and g-crystallins). These
proteins undergo oxidation, nonenzymatic
glycosylation, proteol-ysis, deamidation,
phosphorylation, and carbamylation leading to
aggregation and formation of high-molecular-weight
proteins
70
?????? ????? ?????? ??????? ????????????? ??
?????????? ??????? (????? ?????? ?..) ???? ???
???? ???????? ??? ??? ????? ????
71
These high-molecular-weight (greater than 1,000
nm) protein aggregates interfere with light
transmission and cause light scattering in
nuclear cataracts.
72
???? ???????? ?????????? ??????? (???? ??nm 1000)
??? ??????? ?? ?????? ????? ? ?????? ?? ?????
??????
73
Chemical modification of the nuclear lens
protein also leads to yellowing, followed by
browning, and in advanced stages blackening.
74
???? ???????? ?????????? ??? ????? ?????? ???
???? ????? ???? ?? ????.
75
POSTERIOR SUBCAPSULAR CATARACT
76
????? ??? ??????? ??????
77
????? ?????? ????? ??? ?????? ????? ???? ????
?????? ??? ???????? ?????
78
complain of subjective symptoms such as glare
disability and difficulty focusing on objects,
especially when they are near.
79
?????? ?? ??????? ???? ?????? ??????? ???
???????? ????? ???????
80
During surgery, excessively vigorous scraping or
vacuuming of the calcified opacity can lead to
rupture of the posterior capsule.
81
??????? ?????? ??????? ??????? ???? ???????? ???
??????? ??????? ???? ?? ???? ??? ?????? ???????
???????? ???? ?? ?? ???? ??? ?????? ??? ???? ???
????? ????? ??? ??????? ???????? ?????? ????.
82
These cataracts are commonly thought to be due
to migration of bow region cells into, as well as
accumulation of cellular debris in, the potential
space between the posterior capsule and the cortex
83
????? ?? ?????? ????? ????? ??????? ???????? ???
????? ???????? ????????? ???? ????? ????????
84
result from irradiation or steroid ingestion, or
it may be associated with degeneration (e.g.,
retinitis pigmentosa), and gyrate atrophy.
diabetes, high myopia, retinal
85
????? ????? ??? ??????? ??????? -??????
???????????? ?????? ????? ?????? ?????? ???????
??????? gyrate atrophy
86
In some cases, the PSC eventually may be pushed
to the cortex as new fibers are laid down and the
offending agent is no longer present
87
???? ?? ????? ??????? ??? ??????? ??????? ??????
?????? ????? ????? ????? ?? ????? ?????? ??? ????
?????? ??????
88
MIXED CATARACTS
89
????? ???????
90
(No Transcript)
91
ataract may start as a pure type, but eventually
become mixed as the other lens regions become
involved
92
???? ?? ???? ????? ???? ?? ??????? ????????
?????? ???? ??? ??? ???? ??????
93
a mixed cataract indicates that the cataract has
already advanced to some degree and that its
progression should be watched more closely. These
patients tend to have more visual symptoms and
may need surgery sooner.
94
????? ??????? ??? ?? ????? ?? ??? ???? ?? ????? ?
??????? ?????? ??? ?? ????? ????? ??? ???????
??????? ?????
95
Presenile Cataracts
96
????? ??? ??????
97
These cataracts occur in patients less than 55
years of age and are predominantly PSCs
98
????? ???? ??? ?? 55 ??? ????? ???? ????? ???
?????? ?????
99
The PSCs progress very rapidly and may cover the
entire posterior capsule within a year.
100
????? ????? ????? ?? ??????? ??????? ???? ???
101
the lens epithelium may show subtle changes,
followed by edema and ultimately decompensation
102
???? ?? ???? ??????? ?????? ????? ?? ????? ??
????? ????????
103
The lens nucleus may remain clear for some time,
but eventually it also opacifies. The lens
cortex, also may not be involved initially, but
eventually spoke opacities will develop,
progressing very rapidly.
104
???? ???????????? ?????? ???? ?? ?? ???????
?????? ??????
105
Some studies have suggested an abnormality in
galactose metabolism, such as heterozygosity, and
therefore decreased activity in one of the
galactose metabolic enzymes
106
?????? ??? ???????? ??????? ?? ??????? ?????????
???? ?????? ???? ?????? ???????? ?????????
107
??????? ???????? ????
108
OTHER LESS FREQUENT AGE-RELATED ANATOMIC CATARACT
TYPES
109
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110
Capsular (Including Polar) Cataracts
111
???? ???????(???? ??????)
112
(No Transcript)
113
(No Transcript)
114
The lens capsule may develop localized opacities
in age-related cataracts
115
???? ?? ???? ???? ??????? ??????? ?????? ?? ?????
??????
116
(No Transcript)
117
they are more often associated with persistent
pupillary membranes or epicapsular stars, and
they may also occur in uveitis in association
with posterior synechiae or secondary to injury
caused by drugs, radiation, or trauma. Capsular
thickening may also occur in heat (glassblowers')
cataract, and localized thickening may occur in
Lowe's syndrome as well as in Miller's syndrome
118
?????? ????? ???? ?? ???? ?????? ?????? ?????????
?????? ???????? ???????? ?????????? ??????? ?????
?????? ??????? ??? ????? ?????? ?????? Lowe's
syndrome ,Miller's syndrome
119
Localized central capsular cataracts (polar
cataracts) can occur in the anterior and
posterior capsule and are usually congenital,
although they may also be secondary to trauma.
120
??????? ???????? ??????? ???????? ( ???????
???????)???? ?????? ???? ? ?????? ???? ?? ????
?????? ??????
121
Polar cataracts are usually dense, localized, and
nonprogressive. Because they are stable, many
patients may be able to tolerate them and may
retain good, adequate vision with conservative
treatment
122
???? ??????? ??????? ????? ?????? ????
??????????????? ???? ?? ????? ?????? ????? ????
?????? ??????? ??????? (????? ?????? ?????????
??????? ?? ????? ?????? )
123
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124
Anterior Subcapsular Cataracts
125
????? ??? ?????? ???????
126
consist of multilayering of the anterior lens
epithelium and deposition of abnormal lens
capsule.
127
????? ?? ??? ????? ?? ??????? ???????? ???????
?? ??????? ??? ????????
128
also result from local injury or irritation, as
in uveitis or injury due to chemicals or
radiation.
129
???? ???? ?? ???? ??????? ?? ??????? ??? ??
?????? ??? ?????? ?? ???? ????????????? ?? ??????
130
Lens Epithelial Decompensation
131
?????? ?????? ????? ???????
132
the entire anterior lens epithelium is observed
to be edematous with resulting generalized haze
.This is usually followed within a short period
of time (a few months to 1 year) by development
of cortical and PSC cataracts that mature quickly
and cause severe, rapid loss of vision
133
?????? ?? ??????? ???????? ?? ???? ??? ???????
????? ???? ????? ???????? ???????
134
Retrodots Retrodots are round, translucent
opacities that usually occur in the deep cortex
or perinuclear region. In general, they do not
seem to affect vision until a mixed cataract
appears
135
?????? ??????? ???? ????? ?????
????? ???? ?? ????? ?????? ?? ??? ?????? ??? ????
?? ?????? ??? ???? ????????????
136
Advanced Cataracts
137
????? ???????
138
"mature" stage. A cataract is termed mature if
the cortex and nucleus are so opaque that one can
no longer see the red reflex. In even more
advanced cases, the white cortex becomes so
liquefied that one can see the outline of the
brown nucleus floating free inside the lens,
which usually settles down with gravity when the
patient rests for a while this is called a
morgagnian cataract . If the lens is noticeably
swollen, the cataract is called an intumescent
cataract if the lens appears silvery white and
desiccated, with some leakage of the cortical
fluid, it is called a hypermature cataract
139
????? ?????? ?????? ???? ??????? ?????? ????
??????? -??????? ????? ?? ????? ??????? ?????
?????? ???? ???????? ??????? ?????? ???????
?????? ?????? ?????? ???? ????? ?????? ???? ???
???? ??????? ?? ??? ?????? ????? ??????
140
(No Transcript)
141
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142
CATARACT ASSOCIATED WITH SYSTEMIC DISEASES
Systemic conditions associated with cataract
formation can be grouped into five broad
categories 1. Metabolic disorders 2. Skin
disease 3. Connective tissue/skeletal disorders
4. Renal disease 5. Central nervous system
disorders
143
????? ???????? ?????? ?????? ???? ??????? ?? ???
???????

• ?????????? ???????????
• ????? ?????
• ????? ?????? ????? ??????????? ???????
• ??????? ???????
• ????? ?????? ?????? ???????

144
CATARACT ASSOCIATED WITH METABOLIC DISORDERS
Diabetes Mellitus
145
????? ???????? ????????? ????????? ????? ??????
146
In diabetes, hyperglycemia leads to the diffusion
of increased amounts of glucose into the lens,
which is then converted into the sugar alcohol
sorbitol by the enzyme aldose reductase.
147
?? ?????? ???? ??? ??? ???? ??? ?????? ????? ??
???????? ?? ?????? ? ??? ????? ?? ?? ??? sugar
alcohol sorbitol ?????? ??????? aldose reductase
148
?????? ?????????? ?? ?????? ???? ??? ????? ?????
???? ??? ?????? ????? ?? ?????? ??? ???? ???
???? ???????
149
Transient changes in refraction may accompany
this swelling in some diabetic patients, which
may be either a myopic or a hyperopic shift.
Diabetics also exhibit a decreased amplitude of
accommodation.
150
???? ?? ???? ?????? ???????? ????? ?????? ???????
?????? ? ??? ???? ?? ???? ????? ?? ???? ? ?????
???????? ??? ?????? ??????
151
Two types of cataracts result from diabetes. The
first one is the true diabetic (snowflake)
cataract, which is quite rare. It is usually
bilateral, occurs rapidly, and is usually related
to very high, uncontrolled levels of serum
glucose in young diabetics. The word "snowflake"
is used to describe these cataracts because in
the early stages one notices multiple white
anterior and posterior subcapsular and cortical
opacities as well as vacuoles
152
???? ????? ????? ????? ????? ?????? ??????? ????
??? ????? ??? ???? ???? ?????? ???????? ??
??????? type II ?? ??????? ??????? ????? ???
????? ??? ?????????????? ??? ?????
153
The second and more common type is the
age-related diabetic cataract, which occurs in
type II diabetics.
154
in the early stages one notices multiple white
anterior and posterior subcapsular and cortical
opacities as well as vacuoles . Later, as more
lens fibers become involved, water clefts appear
in the cortex and the lens becomes swollen and
opaque
155
?? ??????? ??????? ????? ?????? ????? ??? ??????
????? ??????? ?????? ??????? )????? ???? ????) ?
?????? ????? ???? ????? ?????? ?????? ??????
156
????? ?????? ?????? ??????? ?? ????? ??????
??????? ??????
157
very similar to other age-related cataracts and
may present as a cortical, posterior
subcapsular,or (less frequently) nuclear cataract
158
???? ?? ???? ????? ?? ??? ????? ???? ?? ????? ???
??? ?????
159
have an earlier onset than other age-related
cataracts, and these patients undergo cataract
surgery sooner
160
???? ???? ?? ????? ??????? ?????? ?????? ???????
???? ??????? ?????? ?????????? ????? ?????? ?????
???????? ?????? (????? ?????? ..)
161
????? ???????? ??????? ???????? ?????? ????? ???
?????? ???? ??? ????? ???? ?? ??????? ???? ?????
???????? ????????
162
Congenital and early developmental cataracts
163
????? ??????? ????????
164
common ocular abnormalities and are an important
cause of significant visual impairment in
childhood. between 10 and 38.8 of all blindness
in children is caused by congenital cataracts
165
???? ???? ???? ??? ????? ??? ??????? (10-38
?? ????? ??? ??????? )
166
one of every 250 newborns (0.4) has some form
of congenital cataract
167
1?? ?? 250 ???? 0.4 ?? ??????? ?????? ????? ??
????? ???????
168
CLINICAL PRESENTATION
169
??????? ????????
170
For a cataract to be seen in ordinary
illumination the opacity must occupy the anterior
portion of the lens.
171
???? ?? ??? ????? ???????? ??????? ?? ???? ?????
????? ??????? ??????
172
Infants with dense bilateral cataracts will
develop nystagmus, often of the wandering or
searching type, by 3 months of age. This type of
nystagmus indicates a poor visual prognosis, with
the best visual acuity of 20/200 (6/60) or less
173
????? ??????? ??? ???? ????? ????? ?????? ???? 3
???? ?? ??????? ?????? ? ??? ??? ??? ????? ???
??? ???? ?????? ??????? ?????? 0.1 ?? ???.
174
The reduced visual acuity in the pediatric
patient with a cataract creates a sensory
obstacle to fusion that may precipitate an ocular
deviation
175
???? ????? ????? ???? ???? ?????
176
reported a 46 occurrence of strabismus in their
series of 453 consecutive childhood cataract
cases either prior to or following surgery(1977)
177
????? ????? ? Hiles and Sheridan ???? 46??
????? ??? 453 ?? ????? ??????? ??? ?? ??? ???????
(1977).
178
lens opacity causes scattering of light or
glare, producing photophobia as a presenting
symptom (lamellar or zonular type). In addition,
parents may notice their infant lacks visual
attention to the environment
179
???? ????? ?????? ??????? ?? ?????? ?????? ??
????? ???? ??? ???? ??????? ??????? ?????? ??
?????? ??? ????? ? ?????? ????? ??? ??????????
??? ????????
180
. An ophthalmologist may be consulted when a
child has a systemic disorder or syndrome in
which cataracts are associated. Usually the
systemic involvement is more apparent than the
ocular involvement.
181
?????? ???? ?????? ???? ??????? ?????? ?????????
???????? ????? ?????? ?? ???? ??????? ????????
??? ????? ?? ???????
182
The infant with searching nystagmus and
cataracts sufficiently dense to prevent a view of
the fundus does not present a therapeutic
dilemma. These children have a profound visual
impairment and require immediate surgery
183
INITIAL ASSESSMENT AND INDICATIONS FOR TREATMENT
184
??????? ??????? ???????? ???????.
185
????? ????? ?????? ??????? ?????? ???? ??????
??? ????? ?? ???????? ??????? ??? ???????-?????
??????? ????? ??????? ???? ??????
186
????? ????? ?????? ??? ?????? ???? ???? ??????
??? ????? ???????? ??????? ?????????? ?? ????
???????
187
????? ????? ?????? ????? ??????? ?? ???? ????
??? ????? ???????? ??????? ???? ???? ??? ????????
?????????-???? ??????? ??? ???? ??????
??????? ???? ???? ???? ?????? ??????? ?????
????? ??????? ? ????? ??? ????? ??????? ??? ????
?????? ??????? ??? ?? 0.3
188
?? ????? ???? ?????? ????? ??????? ?? ????????
?????? ?? ????? (??????? ?????? ??????) ?????
????? ???????? ??? ????? ????? ????? ?? ????? ???
???????
189
???? ??????? ?? ??? ????? ???? ??? ???? ???????
??? ????? ?????? ????? ??? ???? ???? ???? ???
????? ????? ????? ?? ?????? ??? ????? ???????
???????
190
The difficult decisions arise in those children
in whom objective measurements of their vision
are not feasible (secondary to young age or
mental retardation) and who have no nystagmus
191
???? ?????? ???????? ???? ??? ??????? ????? ????
????? ??? ?????? ??????? ?????? ?????? ????????
192
The absence of nystagmus could be attributable to
the cataract being monocular, the vision being
better than 20/200, or the cataract becoming
significantly dense at 1 to 2 years of age (after
development of the fixation reflex
193
???? ???? ??????? ?

• ????? ???? ??????
• ?????? ???? ?? 0.1
• ???? ????? ???? 1-2 ???(??? ???? ????? ??????? )

194
In this group of patients a careful history of
the child's performance is helpful. How does the
child function in a strange environment? Does the
child recognize familiar faces or easily find
small objects of interest?
195
??? ??? ?????? ???? ???????? ???

• ??? ????? ????? ?? ???? ??? ??????
• ?? ????? ??? ??????
• ?? ???? ??? ??????? ???????

196
If an adequateic reflex cannot be obtained for
refraction (central lens opacity greater than 3.0
mm) or the retina cannot be visualized with a
direct ophthalmoscope, the cataract is visually
significant and prompt surgical intervention
should be considered.
197
????? ?????? ???? ??? ????? ?????? ??? ?????
??????? ?? ?? ???? ???? ??????? ?????????? ???
?????? retinoscope( ????? ??? ???? ????? ??????
???? ?? 3 ?? )????? ????? ??????? ???????
198
Any associated ocular anomalies, such as
microphthalmos, foveal hypoplasia, and strabismus
199
???? ?? ????? ???? ???? ??? ?????? ???????? ???
???? ?????? ? ??? ???? ?????? ???????
200
A relative afferent pupillary defect is a poor
prognostic sign, usually indicating significant
asymmetrical optic nerve dysfunction or severe
retinal pathology.
201
???? ???? ????? ?? ????? ?????? (Marcus Gunn
pupil) ???? ???? ???? ????? ??????? ????? ?????
?????? ????? ??? ??? ???????
202
Retinal detachments, vitreal opacities,
intraocular foreign bodies, and posterior segment
tumors should be excluded with B-scan
ultrasonography in all patients in whom
visualization of the posterior segment is
inadequate.
203
??? ??? ??????? ?? ?????? ??????? ????????
??????? ?????? ?????? ? ???????? ?????? ?????
????? ????? ??? ??? ?????
204
the visual result is not related to the
morphologic type of cataract or its size but
rather to its density.
205
????? ??????? ??? ????? ????? ???? ?? ??????
?????? ?? ????
206
Consideration must be given to the chance of
progression of the lens opacity, and repeated
examinations are indicated. congenital anterior
polar cataracts can progress and become visually
significant. Posterior lentiglobus, a bulge of
the infant's posterior lens capsule, generally
progresses and is associated with the development
of cataractous changes in the cortex
207
???? ???????? ??? ??????? ???? ?????

• ????? ?????? ??????? ???? ?? ????? ?? ?????
• ?????? ????????? ??????? ???? ?? ????? ?? ?????
  ??????? ?????

208
When a child reaches about age 3, vision can
usually be measured with pictures
209
??? ???? ????? ??? 3 ????? ???? ??? ??????
????????? ????? ?????
210
The level of visual impairment to prompt cataract
surgery in children varies with their age and
functional needs.
211
????? ???? ?????? ????????? ???? ????? ???????
??? ??? ????? ?????? ?????????? ???????
212
While 20/70 (6/21) vision for an adult may be
unacceptable, a 3-year-old child with that level
of vision would probably do quite well
213
?? ??? ???? ?? ???? ????? ??????? 0.3 ??? ??????
??? ?????? ? ??? ???? ???? 3 ????? ?? ??????
??????
214
As a child reaches school age his visual demands
increase and a near vision of approximately 20/70
or worse from a lens opacity would be an
indication for surgery.
215
???? ??????? ????? ??? ?????? ??? 0.3 ????????
???????
216
The possibility of amblyopia in a child under
age 9 with bilateral unequal cataracts may
present a dilemma in management.. A trial of
patching and possibly dilating drops to maintain
visual potential is reasonable. However, if the
visual acuity in the amblyopic eye is not
improved with conservative measures, cataract
surgery should be considered
217
??? ???? ????? ???? ?????? ??? ??? ??? ??????
??????? ???????? ????? ??????? ???? ??? ???????
218
The major factor responsible for the poor visual
prognosis in the monocular congenital cataract
patient is irreversible deprivation amblyopia.
219
????? ??????? ??????? ?????? ????? ?? ????? ???
?????? ???????
220
Experiments with animal models have disclosed
that unilateral eyelid closure causes
irreversible neural changes in several visual
centers after only several weeks of visual
deprivation. Wiesel and Hubel found atrophy of
the corresponding cells in the lateral geniculate
body and a marked decrease in the striate cells
that could be driven by the deprived eye after
monocular sight deprivation in newborn kittens.
221
???? ??????? ??? ????????? ?????? ??? ?????
?????? ?? ????? ?? ??????? ??????? ??????? ???
?????? ??? ?? ????? ???????
222
This CONGENITAL AND DEVELOPMENTAL CATARACTS Vol 1
/ Chap 74 3 experimental work correlates well
with the clinical experience of almost uniform
dismal visual results despite successful surgery
and optical rehabilitation in patients with
unilateral congenital cataracts.
223
????? ??? ??????? ?? ??????? ???????? ?? ??? ????
?????? ??? ??????? ??????? ???? ?????
224
Associated ocular anomalies such as
microphthalmos, nystagmus, foveal hypoplasia, and
strabismus, which occur in 30 to 70 of eyes
with monocular cataracts, further complicate
management and prognosis.
225
???????? ???????? ?????? ????? ????? ?? 30-70??
??????? ???? ??? ???????
226
failure to achieve good visual results in
monocular congenital cataracts does not alter the
appropriateness of surgical intervention in many
of these cases.
227
????? ?? ?????? ??? ???? ???? ???? ?????? ?????
???????
228
peripheral field of vision is improved with
surgery and that the tendency for strabismus may
be reduced.
229
????? ?????? ??????? ???? ????? ??? ?????
230
surgical intervention of a monocular congenital
cataract is indicated for reasons other than to
improve vision. Lens-induced inflammation and/or
glaucoma and the cosmetic advantage of a clear
black pupil are such indications
231
????? ??????? ?????? ??? ????? ????? ??? ????????
?????? ? ???????
232
cataract associated with persistent hyperplastic
primary vitreous (PHPV) should be removed to
reduce the risk of late complications and
preserve the globe even though the final visual
result is usually poor progressive cataract with
shallowing of the anterior chamber and resultant
angle-closure glaucoma often necessitating
enucleation
233
Etiologies of Congenital and Developmental
CataractsI. Mendelian InheritanceA. Autosomal
dominantB. Autosomal recessiveC. X-linkedII.
Intrauterine InfectionA. RubellaB.
Chickenpox/herpes zosterC. Herpes simplexD.
CytomegalovirusIII. PrematurityIV. Metabolic
DisordersA. GalactosemiaB. HypoparathyroidismC.
PseudohypoparathyroidismD. Diabetes mellitusE.
Refsum's syndromeF. Oculocerebrorenal (Lowe's)
syndromeG. HypoglycemiaH. MannosidosisI.
Hereditary familial congenital hemorrhagic
nephritis (Alport's syndrome)V. Chromosomal
DisordersA. Trisomy 21 (Down's syndrome)B.
Trisomy 13C. Trisomy 18VI. Ocular
AbnormalitiesA. MicrophthalmiaB. Mesodermal
dysgenesisC. ColobomaD. AniridiaE. Persistent
pupillary membraneF. Posterior lenticonusG.
Persistent hyperplastic primary vitreousVII.
Systemic SyndromesA. Hallermann-Streiff
syndromeB. Marinesco Sjogren Marinesco-Sj?gren
syndromeC. Congenital stippled epiphysis
(Conradi's) syndromeD. Myotonic dystrophyE.
Smith-Lemli-Opitz syndromeF. Stickler's
syndromeG. Cerebral gigantism (Soto's)
syndromeH. Potter's syndromeI.
Chondrodystrophic myotoniaJ. Schwartz-Jampel
syndromeK. Cockayne's syndromeL. Meckel's
syndromeM. Rubenstein-Taybi syndromeVIII.
Dermatologic DisordersA. Poikiloderma
atrophicans (Rothmund-Thomson syndrome)B.
Congenital ichthyosisC. Ectodermal dysplasiaD.
Incontinentia pigmenti of Bloch-SulzbergerE.
Atopic dermatitisIX. Craniofacial DysostosisA.
Crouzon's syndromeA. Crouzon's syndromeB.
Apert's syndromeC. Oxycephaly

• ????? ????? ???????

234
????? Reger ??? ???? ????? ??? ??? ???? ??????
?? ??????? ?????? ????? ??????
235
???? ????? ???????? ????? ??????? ?????? ??????
??? ????? ??? ??? ??????? ?????? ??? ????? ????
????? ????? ???????? ????? ?????
236
In the case of a congenital cataract in an
otherwise healthy child, galactokinase deficiency
must be excluded., cataract formation may be the
sole manifestation of another form of
galactosemia in which the enzyme galactokinase is
deficient. It is important to screen all patients
for galactosemia since it is known that early
diagnosis and prompt institution of therapy by
elimination of galactose from the diet can result
in regression of the cataract and improvement of
the other signs of the disease.
237
?????????? ??? ????? ?? ????? ??? ?????????????
??? ???? ?? ???? ?????? ?????? ????? ????? ???
?????? ??? ??? ????? ??? ?????? ?????? ???? ??
???? ???? ????????? ?? ?????? ??? ????? ?????
238
In a child who is otherwise healthy,
approximately one third of cataract cases are
idiopathic. Many of these idiopathic cases are
new mutations, in which the familial nature of
the cataract will be discovered in subsequent
generations. n claim that about 50 of all
hereditary cataracts are new mutations
239
??? ??????? ??????? ???? ??? ????? ????? ?????
????? ???? Freedman ?? 50 ?? ??????? ????????
?? ???? ????? ????? ?????? ??????? ???????? ?????
240
Between 8.3 and 23 of cataracts are familial,
with autosomal dominant heredity being the most
frequent mode of inheritance
241
???? 8.3 -23 ?? ??????? ?????? ????? ???
??????? ?????? ?????? ?? ?????? ??????
242
a parent who has a congenital monocular cataract
may have a child with bilateral cataracts
243
????? ???? ??? ??????? ????? ???? ????? ????
??????? ???? ???? ?? ???? ?? ?????? ???? ????
????? ??????
244
Autosomal recessive inheritance is less frequent
but not uncommon in populations with high rates
of consanguineous marriages. 24 X-linked
inheritance is rare
245
??????? ???????? ??? ?????? ?????? ???? ???
?????????? ??????? ???????? ?????? ??? ?????
246
In all children with cataracts, parents and
siblings should also be examined.
247
??? ????? ??? ????? ???? ??? ?? ????? ????????
248
When no other cause is evident, trauma or an
occult intraocular foreign body must be considered
249
????? ?? ???? ??? ??? ??? ??????? ????? ?? ???
????? ???? ???? ?????.
250
Of those children with bilateral congenital
cataracts requiring surgery, those operated on
prior to 8 weeks of age had the best visual
results.
251
?? ????? ??????? ????? ?????? ???? ???? ???????
?? ??????? ???? ??? ?? 8 ??????
252
none of patients with cataracts and nystagmus had
a postoperative visual acuity of 20/80 (6/24) or
better and no one with microphthalmos exceeded
visual acuity of 20/200. vision of 20/50 (6/15)
or better in only 6 of cases when there was
nystagmus or microphthalmos but in 81 when there
were no other defects.
253
????? ??????? ?? ??? ?? ?? ?????? ??? ????
??????? ???? ??0.2 ?? ???? ??? ??? ?????? 0.1 ???
????? ???? ?? ?????? ??? 0.3 ?? ???? ?? 6??
?????? ?? ??????? ???? ?????? ????? ???? ??? ??
81 ?? ??????? ?? ???? ???????? ???????
254
The interval between congenital cataract surgery
and development of a retinal detachment varies
greatly. Toyofuku and co-workers found the age at
the onset of retinal detachment to vary from 13
months to 56 years, with an average age of 31.9
years.
255
???? ????? ??? ????? ????? ??????? ??????? ?13
???? ??? 56 ??? ?????? 31 ???
256
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???? ?? ?????? ??????? ?????

• ???? 1??? ???? 6 ??????
• ????2 ??? ???? 5 ??????
• ???? 3 ??? ???? 4 ??????
• ????4 ??? ???? 3 ??????
• ???? 5 ??? ???? 2 ?????
• ????6 ??? ????1 ?????
• ????7 ??? ??? ??? ???? ?????? ???? ?????? ???????

257
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????????-(7-?????) ??? ?????? ????? ????????
??????? ??????
258
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259
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???? ?? ???? ????? ??????? ???? ??? ???????
260
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????????? ???? ?????
261
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262
???? ??????? ?????? ??? ?? ????? ???? ???

• ???????
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• ???????? (????)
• ???????
• ???? ????? ?????? ??????? ?????? ?????????? ???
  ??????? ????? ????? (????)
• ??????? ??????? ?????? ??? (????)

263
???? ?????? ???? ??????? ?? ???? ??????? ????
?? ??????? ?????? ???????? ????? ????? ???????
264
?????? ?????? ??????
265
????? ??????? ??? bleu vision ?????? (1\6)
266
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267
???? ??????? 33
268
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269
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270
??????? ????? ????? ??? ??? ????? ????? ?? ??
???? closed environment
271
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272
????? ?? ??????? ??????? ???? 12.0-12.5??
273
????? ?????? ?????? ??????
274
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275
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????????
276
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277
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278
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279
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280
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281
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282
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283
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284
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285
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286
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