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MINISTRY OF HEALTH PROTECTION THE REPUBLIC OF
UZBEKISTAN
TASHKENT MEDICAL ACADEMY
“Approved” by
Protector on the academic work
Prof. Teshaev O.R.
_______________________________
«_____»_________________2012 у.
Department: Eye diseases (Diseases of vision organs)
Subject: Ophthalmology
THEME: “Inherited and acquired lens pathology”.
Education Methodic Elaboration
(for instructors and students of the Higher Medical Schools)
Tashkent -2012 y.
THEME: “Inherited and acquired lens pathology”.
1. Place and facilities for the classes.

A room (dark) used for classes and vision examination in polyclinics.

Necessary facilities: a set of tables slides, mileage of a visual organ, the Roth
apparatus, the Sivtsev-Golovin table, spheroperimeter, the Rabkin polychromatic
tables, and ophthalmoscope.
 Medicaments (solutions for disinfection, eye droplets, local anasthetics)
 Eyelid lifters
 Glass ophthalmic spatulas
 Binocular magnifiers
 Slit-lamp
 Ophthalmoscopes, 13 D magnifiers.
 TV-video, posters, phantoms and moulages, volonteers and patients.
2. Period of time needed
Period of time 5,5 hours
3 . T he a i m
Every doctor should know such visual organs pathology as inborn or acquired
cataract, which takes place in violation of the transparency of optical media eye,
such illness as inborn and acquired cataract. They often are the result of
manifestation general diseases as follows: rheumatism, diabetes, tuberculosis,
chronic and acute infectious diseases, the thyrioid gland pathology, etc. Physicians
should be able to diagnose and treat the patients suffering from this pathology.
Prophylaxis of the development of possible complications in these cases is necessary.
“Inherited and acquired lens pathology” – need to explore this theme
stems from the fact that patients with these pathologies of the vision can go to any
specialist.
Tasks
 Every student should know:
- classification of the inborn and acquired lens pathology;
- etiopathogenesis and diagnostics in the inborn and acquired lens pathology;
- clinical manifestations and principles of treatment of the inborn and acquired
lens pathology;
- complications and prophylactic measures at the inborn and acquired lens
pathology.
 A student of the general practice should be able to diagnose and render initial
medical aid in cases of the inborn or acquired lens pathology.
 SQP should have skills in:
 Elucidation of complaints and the pathology anamnesis in brief;
 Preliminary examination of every eye acuity;
 Examination of the anterior part of an eye and ectropia of the upper eyelid;
 Examination of all the anterior parts of an eye by using the methods of lateral
illumination and biomicroscopy;
 Examination of the lens by the lateral illumination method;
 Dripping eye droplets;
 application of ointments;
 lavage of the conjunctiva cavity;
 application of the aseptic bandage
 definition of the lacrimal ducts permeability, examination of lacrimal secretion,
get acquainted with the method of the lacrimal ducts lavation.
4. Motivation
Every physician should know the symptomatology of the inborn and acquired
lens pathology, some of its forms and types, size, localization, depth of injury,
clinical manifestations of cataract, and stage of its development.
Lens opacity is accompanied by vision depravation including photo perception.
Vision depravation as a rule, results in the development of nystagmus and
heterotropia as well as amblyopia. Lens opacity unfortunately results mostly in
invalidity of the vision organ of patients.
A general practitioner student must be able to diagnose the inborn and acquired
lens pathology, know where the patient will be rendered qualified medical aid.
5. Intersubjects and inter subject relations
-
Knowledge of students on this theme should be good enough and integrated with the
other related subjects vertically and horizontally. The theme is vertical integration
with anatomy (the nerve system and sensory organs, physiology of the nerve system),
histology (ontogenesis and histology of the nerve system and sensory organs),
deontology (in the aspects of a doctor-patient interrelation), history of medicine and
ophthalmology, pharmacotherapy in ophthalmology.
The horizontal integration with:
Otorhinolaryngology (the anatomic neighboring and correlation of various ORL
diseases and vision organ diseases)
Infection diseases and connected with them probable complications in the visual
analyzer
Diseases of Inner organs ( pathology of AD , diseases of blood and kidneys,
collagenoses and others diseases associated with the impairment of visual analyzer)
Endocrinology (diavetes mellitus, hypo and hyperthuy disease of hypophysis
(pituitary gland) and either endocrinopathy.
6. Content of classes.
6.1 Theory.
The lens is biconvex and transparent.It is held in position behind the iris
by the suspensory ligament whose zonular fibres are composed of the
protein fibrillin which attach its equator to the ciliary body.
Disease may affect structure,shape and position.
Cataract
Opacification of the lens of the eye (cataract) is the commonest cause of
treatable blindness in the world.The large majority of cataracts occur in
older age as a result of the cumulative exposure to environmental and
other influences such as smoking,UV radiation and elevated blood sugar
levels.This is sometimes referred to as age-related cataract.A smaller
number are associated with specific ocular or systemic disease and defined
physico-chemical mechanisms.Some are congenital and may be inherited.





OCULAR CONDITIONS
Trauma
Uveitis
High myopia
Topical medication (particularly steroid eye drops)
Intraocular tumour
SYSTEMIC CAUSES
 Diabetes
 Other metabolic disorders (including galactosaemia, Fabry’s disease,
hypocalcaemia)
 Systemic drugs (particularly steroids,chlorpromazine)
 Infection (congenital rubella)
 Myotonic dystrophy
 Atopic dermatitis
 Systemic syndromes (Down’s,Lowe’s)
 Congenital,including inherited,cataract
 X-radiation
SYMPTOMS
An opacity in the lens of the eye:
• causes a painless loss of vision;
• causes glare;
• may change refractive error.
In infants, cataract may cause amblyopia (a failure of normal visual
development) because the retina is deprived of a formed image. Infants
with suspected cataract or a family history of congenital cataracts should
be seen as a matter of urgency by an ophthalmologist.
SIGNS
Visual acuity is reduced. In some patients the acuity measured in a dark
room may seem satisfactory, whereas if the same test is carried out in
bright light or sunlight the acuity will be seen to fall, as a result of glare and
loss of contrast.
The cataract appears black against the red reflex when the eye is
examined with a direct ophthalmoscope. Slit lamp examination allows the cataract to
be examined in detail and the exact site of the opacity can be identified. Agerelated
cataract is commonly nuclear, cortical or subcapsular in location. Steroid-induced
cataract is commonly posterior subcapsular. Other features to suggest an ocular cause
for the cataract may be found, for example pigment deposition on the lens suggesting
previous inflammation or damage to the iris suggesting previous ocular trauma.
INVESTIGATION
This is seldom required unless a suspected systemic disease requires
exclusion or the cataract appears to have occurred at an early age.
TYPES OF CATARACT:
Cortical
Sub capsular
Nuclear
Anterior
Posterior
TREATMENT
Although much effort has been directed towards slowing progression or
preventing cataract, management remains surgical. There is no need to
wait for the cataract to ‘ripen’. The test is whether or not the cataract produces
sufficient visual symptoms to reduce the quality of life. Patients may
have difficulty in recognizing faces, reading or achieving the driving
standard. Some patients may be greatly troubled by glare. Patients are
informed of their visual prognosis and must also be informed of any coexisting eye
disease which may influence the outcome of cataract surgery.
Cataract surgery.
The operation involves removal of most of the lens and its replacement
optically by a plastic implant. It is increasingly performed under local
rather than general anaesthesia. Local anaesthetic is infiltrated around the
globe and the lids or given topically. If social circumstances allow, the
patient can attend as a day case, without admission to hospital.
The operation can be performed:
•Through an extended incision at the periphery of the cornea or
anterior sclera followed by extra-capsular cataract extraction (ECCE). The
incision must be sutured.
•By liquification of the lens using an ultrasound probe introduced
through a smaller incision in the cornea or anterior sclera
(phacoemulsification).Usually no suture is required.This is now the preferred method
in the Western world.
Complications of cataract surgery
1 Vitreous loss. If the posterior capsule is damaged during the
operation the vitreous gel may come forward into the anterior chamber
where it represents a risk of glaucoma or traction on the retina. It
requires removal with an instrument which aspirates and excises the gel
(vitrectomy).In these circumstances it may not be possible to place an
intraocular lens in the eye immediately.
2 Iris prolapse. The iris may protrude through the surgical incision in the
immediate postoperative period. It appears as a dark area at the incision
site.The pupil is distorted. This requires prompt surgical repair.
3 Endophthalmitis. A serious but rare infective complication of cataract
extraction (less than 0.3%).
Patients present with:
(a)a painful red eye;
(b)reduced visual acuity, usually within a few days of surgery;
(c)a collection of white cells in the anterior chamber (hypopyon).
The patient requires urgent ophthalmic assessment, sampling of aqueous
and vitreous for microbiological analysis and treatment with intravitreal,
topical and systemic antibiotics.
4 Postoperative astigmatism. It may be necessary to remove the corneal
sutures in order to reduce corneal astigmatism.This is done prior to measuring the
patient for new glasses but after the wound has healed and
steroid drops have been stopped. Excessive corneal curvature can be
induced in the line of the suture if it is tight. Removal usually solves this
problem and is easily accomplished in the clinic under local anaesthetic with the
patient sitting at the slit lamp. Loose sutures must be removed to
prevent infection but it may be necessary to resuture the incision if healing
is imperfect. Sutureless phacoemulsification through a smaller incision
avoids these complications. Furthermore, placement of the wound may
allow correction of pre-existing astigmatism.
5 Cystoid macular oedema. The macula may become oedematous following surgery,
particularly if this has been accompanied by loss of vitreous. It may settle with time
but can produce a severe reduction in acuity.
6 Retinal detachment. Modern techniques of cataract extraction are
associated with a low rate of this complication. It is increased if there has
been vitreous loss.
7 Opacification of the posterior capsule (Fig.8.4).In approximately 20%
of patients clarity of the posterior capsule decreases in the months following surgery when residual epithelial cells migrate across its surface. Vision
becomes blurred and there may be problems with glare. A small hole can be made in
the capsule with a laser (neodymium yttrium (ndYAG) laser) as an
Outpatient procedure. There is a small risk of cystoid macular oedema or
retinal detachment following YAG capsulotomy. Research aimed at reducing this
complication has shown that the material used to manufacture the
lens,the shape of the edge of the lens and overlap of the intraocular lens
by a small rim of anterior capsule are important in preventing posterior
capsule opacification.
8 If the fine nylon sutures are not removed after surgery they may break
in the following months or years causing irritation or infection. Symptoms
are cured by removal.
Congenital cataract
The presence of congenital or infantile cataract is a threat to sight,not
only because of the immediate obstruction to vision but because disturbance of the
retinal image impairs visual maturation in the infant and leads
to amblyopia (see pp.170–171).If bilateral cataract is present and has a
significant effect on visual acuity this will cause amblyopia and an oscillation of the
eyes (nystagmus).Both cataractous lenses require urgent
surgery and the fitting of contact lenses to correct the aphakia.The management of
contact lenses requires considerable input and motivation
from the parents of the child.
The treatment of uniocular congenital cataract remains controversial.
Unfortunately the results of surgery are disappointing and vision may
improve little because amblyopia develops despite adequate optical correction with a
contact lens.Treatment to maximize the chances of success
must be performed within the first few weeks of life and be accompanied
by a coordinated patching routine to the fellow eye to stimulate visua
maturation in the amblyopic eye.Increasingly intraocular lenses are being
implanted in children over 2 years old.The eye becomes increasingly
myopic as the child grows,however,making choice of the power of the
lens difficult.
CHANGE IN LENS SHAPE
Abnormal lens shape is very unusual. The curvature of the anterior part
of the lens may be increased centrally (anterior lenticonus) in Alport’s
syndrome, a recessively inherited condition of deafness and nephropathy
An abnormally small lens may be associated with short stature and
other skeletal abnormalities.
CHANGEINLENSPOSITION(ECTOPIALENTIS)
Weakness of the zonule causes lens displacement.The lens takes up a
more rounded form and the eye becomes more myopic.This may be
seen in:
•Trauma.
•Inborn errors of metabolism (e.g.homocystinuria,a recessive disorder
with mental defect and skeletal features.The lens is usually displaced
downwards).
•Certain syndromes (e.g.Marfan’s syndrome,a dominant disorder with
skeletal and cardiac abnormalities and a risk of dissecting aortic aneurysm.
The lens is usually displaced upwards).There is a defect in the zonular
protein due to a mutation in the fibrillin gene.
The irregular myopia can be corrected optically although sometimes
an aphakic correction may be required if the lens is substantially displaced
from the visual axis.Surgical removal may be indicated,particularly if the
displaced lens has caused a secondary glaucoma but surgery may result in
further complications.
CATARACT—THE WORLD PERSPECTIVE
In the developed world cataract surgery is performed when visual symptoms interfere
with the quality of life.Worldwide there are in excess of 20
million people blind due to bilateral dense cataract.This represents a huge
cause of preventable blindness.The World Health Organization has established
Project 2020 to manage this problem;the goal is to remove cataract
as a cause of blindness by the year 2020.
The new pedagogic technology used at this lesson: “Black box”, “Web-Net”
The “Black box” method.
It provides the interconnected activity and active participation of every student, the
tutor (teacher) involves the whole group in this activity.
Every student pulls out a card from the box. In the card there are writer in short
complaints and clinical manifestations of a disease (variants are given)
Students should determine this preparation; give their answer in details and groud it.
To think over the answer it is given 3 minutes. Then the answer is discussed and
additional information on clinical characteristics and ways of the disease are given.
At the end of this part of classes teacher comments the answers ( its correctness,
grounded and level of the students’ activity)
This method helps to improve the students’ speech; to obtain the vases of critical
thinking as the students are taught to advocate their opinion, analyze answers given
by their group-mates participated in the competition.
Variants of cards:
1.
Diagnosing a disease: acute iridocyclitis
Treatment: midriatics, antiinflammation therapy antibiotics therapy.
2.
Diagnosing a disease: mature age cataract
Treatment: surgery (EEK+IOL)
Usage of the “web” method
Steps:
1.
First, students are given some time for composing questions to the studied
theme.
2.
The participants sit in a circle
3.
One of the participants who is given a clew puts his question ( he should know
the detailed answer to it) and holding the end of the thereoat passes the clew
4.
A student who has received the clew must answer this question ( the student
who has put the question should comment the given answer) and passes the clew to
some other student. The participants must go on with asking and answering the
questions until all of them are involved in the web.
5.
As soon as every student has put his question, the last participant who keeps
the clew should return it to the previous one who put him a question and son. The
game continues until the “web” is “unfailed”: completely.
Note: students should be warned to listen attentively every answer because they
don’t know who will be the next.
6.2. Practical part
Examination of photo perception.
№
Content of answer
a
table
Answer is
complete
Points
Answer is
not
complete
No answer
1
It is necessary:
ophthalmoscope
lamp,
15
7,5
0
2
Every eye is examined separately by
closing one eye with a palm or
covering detachment.
15
7,5
0
3
The lamp should be adjusted at the
left back side from the patient.
15
7,5
0
4
Light of the lamp should be directed
by a concave mirror to the examined
eye from various sides (up, down, left
and right).
15
7,5
0
5
If the patient sees the light and
defines its direction properly, his
(her) vision acuity is considered to be
equal to the photo perception with
correct photo projection
15
7,5
0
15
7,5
0
10
5
0
100 points
50
0
1

(vis= pr l. certa)
6
If the patient is wrong in defining the
light projection even from one side
only, such vision is considered as
photo perception with non-correct
photo projection.
1

(vis= pr l. incerta)
7
If the patient does not have any photo
perception, his (her) vision acuity is
considered to be zero (vis=0)
Total
points
Tasks
Definition of the vision aquity.
№
1
2
3
4
5
6
7
8
Content of answer
Necessary facilities: the Roth
apparatus, Sivtsev-Golovin table or a
table with distant control (Forroptr),
pointer.
The Roth apparatus and the SivtsevGolovin table or a table with distant
control (Forroptr) should be adjusted
at the 5 meters distance from the
examined person (the tenth line
should be at he same level with the
patient’s eyes).
Every eye should be examined
separately by covering the fellow
one with a screen.
Definition of the vision acuity should
be started with indication of
optotypes on the tenth line (row) –
vis = 1.0, by pointing to optotypes
located on various rows (from lower
line to upwards).
If patients have depraved vision the
examination may be started with the
first upper row and downwards.
The vision acuity is estimated by that
row where all the optotypes were
defined correctly (the 1-st row = 0,1;
the 2-nd = 0,2 etc).
If the patient cannot differentiate
optotypes on the first row the vision
acuity is controlled by showing the
hand fingers and then is counted
with Snellen’s formula
Vis= d where “d” – is a distance
D at which the patient can
distinguish number of hand fingers
D=50 m.
In case when things vision is absent,
the photo perception should be
examined by direction of light. Photo
perception might be adequate or
wrong.
Answer is
complete
Points
Answer is
not
No answer
complete
10
5
0
10
5
0
10
5
0
10
5
0
10
5
0
10
5
0
20
10
0
10
5
0
If the photo perception is absent the
vision acuity is considered to be
“zero”.
9
10
100 points
Total
5
50
points
0
0 points
7. Forms of controlling the level of knowledge, practice
and skill.
 Oral
 Tests
 Demonstration of practical skills
8. Criteria for estimation of the current control.
№
№
1
2
Results in
percents
and points
96-100%
Marks
Graduation of a student’s knowledge
Excellent “5”
91-95%
Excellent “5”
Full and correct answer to questions on
etiopatogonesis, classification, clinics,
principles of treatment, complications and
prevention. Summarizes and takes a decision,
creative thinking, analyzes independently.
Properly solves situational challenges with
creative approach, with full explanation of the
answer.
Takes part actively in interpersonal games,
properly takes grounded decisions and
summarizes, analyzes. Implementation of
practical skills in all stages is error free and
complete.
Full and correct answer to questions on
etiopatogonesis , classification, clinics,
principles of treatment, complications and.
Creative thinking, analyzes independently.
Properly solves situational challenges with
creative approach, with explanation of the
answer. Takes part actively in interpersonal
games, properly takes decisions.
Implementation of practical skills in all stages
3
86- 90%
4
81-85%
5
76-80%
6
71-75%
7
66-70%
is error free and complete.
Excellent “5” Fully highlighted questions on
etiopatogonesis , classification, clinics,
principles of treatment, complications and
prevention, but 1-2 uncertainties in answer.
Analyzes independently. Uncertainties while
taking decision in solving case studies but
with correct approach. Takes part actively in
interpersonal games, properly takes decisions.
One mistake during whole stages of
implementation of practical skills.
Good “4”
Fully highlighted questions on
etiopatogonesis, classification, clinics,
principles of treatment, complications and
prevention, but there are 2-3 uncertainties and
mistakes. Puts into practice, understands
point of question, retells confidently, has an
exact ideas. Case studies are solved correctly
but explanations are not full.
Some uncertainties while implementing
practical skills along the stages.
Good “4”
Answer is correct but not fully highlighted. A
student knows etiopatogonesis,
classification, clinics, principles of treatment,
complications, but is not good at prevention.
Understands point of question, retells
confidently, has an exact ideas. Takes part
actively in interpersonal games. Incomplete
decisions to case studies. Incomplete
implementation of 1st level while taking
practical skills.
Good “4”
Answer is correct but not fully highlighted.
A student knows etiopatogonesis ,
classification, clinics, but is not good at
principles of treatment, complications and
prevention. Understands point of question,
retells confidently, possesses exact ideas.
Incomplete decisions to case studies. 1st stage
was not completed while implementing
practical skills along the stages.
Acceptable “3” Correct answer to half of the question. A
student knows inetiopatogonesis,
classification, but not well at in clinics,
principles of treatment, complications and
prevention. Understands point of question,
8
61-65%
9
55-60%
10
50-54%
11
46-49%
12
41-45%
retells confidently, and possesses insight of
particular questions. Case studies are solved
correctly but without explanation. 2 stages
were not completed while implementing
practical skills.
Acceptable “3” Correct answer to half of the question.
Mistakes in etiopatogonesis , classification,
bad at clinics and principles of treatment,
confuses in complications and prevention.
Retells unconfidently, possesses exact ideas
in separate themes. Makes mistakes while
solving case studies. 2 stages were absolutely
incomplete while implementing practical
skills.
Acceptable “3” Answer is with mistakes to half of the
question. A student makes mistakes in
etiopatogonesis, classification, bad at clinics
and principles of treatment, confuses in
complications and prevention. Retells
unconfidently, possesses ideas of theme
partially. Case studies are solved incorrectly.
Incomplete implementation of 3 stages while
taking practical skills.
Unacceptable Correct answer to 1/3 of the question. A
“2”
student does not know in etiopatogonesis,
classification, bad at clinics and principles of
treatment, confuses in complications and
prevention. Case studies are solved
incorrectly with wrong approach. Absolutely
incomplete 3 stages while implementing
practical skills along the stages.
Unacceptable Correct answer to 1/4 of the question. A
“2”
student does not know in etiopatogonesis,
classification, bad at clinics and principles of
treatment, confuses in complications and
prevention. Case studies are solved
incorrectly with wrong approach. Absolutely
incomplete 4 stages while implementing
practical skills along the stages.
Unacceptable Correct answer to 1/5 of the question. A
“2”
student does not know in etiopatogonesis,
classification, bad at clinics and principles of
treatment, confuses in complications and
prevention. Case studies are solved
incorrectly with wrong approach. Absolutely
13
36-40%
Unacceptable
“2”
14
31-35%
Unacceptable
“2”
incomplete 4 stages while implementing
practical skills along the stages.
Correct answer to 1/10 of the question. A
student does not know in etiopatogonesis,
classification, bad at clinics and principles of
treatment, confuses in complications and
prevention. Case studies are solved
incorrectly with wrong approach. Absolutely
mistakes while implementing practical skills
along the stages.
There are no answers for the questions.
A student does not know in etiopatogonesis,
classification, bad at clinics and principles of
treatment, confuses in complications and
prevention.
A student does not know practical skills along
the stages.
9. Chronologic Charta of the classes.
№
Sequence
1.
Introduction
2.
Analysis of the home-task
3.
Curation and reception of patients
4.
Kind of the
lesson
Analysis of the practical part of the lesson
6.
Analysis the lessons in the forms of seminars
and by making reports on the theme of the
obtained know ledge by using interactive
methods ( brain ring, snowballs, gallery tour
ones).
(225 min)
15 min
Inquest
Explanation
40 min
Making a
doctor’s
round
30 min
Mastering of practical skills, methods
examination using medical instruments
(facilities).
5.
Period
30 min
Inquest
Explanation
30 min
Reports,
seminar
30 min
7.
Facilities for teaching at the lesson: video
cassettes, computer programs, situation tasks.
30 min
8.
Conclusion made by the teacher, marks
gained by every student according to the 100
point system. Home task for the next classes.
20 min
Total
225 min
10. Questions for control.
1.
2.
3.
4.
5.
A lens.
Various types of cataracts.
The inborn cataracts.
The secondary cataract.
Surgical methods of cataract treatment.
11. Literature.
Basic:
1.
2.
3.
4.
5.
Eroshevsky T.I., Bochkarev A.I. “Eye diseases”, 1989.
Kovalevsky E.I., Selected lectures, A text-book – M: Medicine, 1996.
Kovalevsky E.I., “Eye diseases” (Atlas) – М.: Medicine, 1985.
Khamidova M.Kh. «Kuz kasalliklari», 1996.
Fedorov S.N., et al. «Eye diseases»-М. 2000.
Supplementary :
1. Doljitch P.N., Eye diseases in the form of questions and answers, 2003.
2. Multivolume handbook on the Eye diseases.
3. Therapeutic ophthalmology. Ed. By Shulpina N.B.