white pupil - howMed Lectures

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Brig Amer Yaqub
MCPS, FCPS, FRCSEd
WHITE PUPIL
Causes of White Pupil
DIFFERENTIAL DIAGNOSIS
OF WHITE PUPIL
Cataract
Causes of White Pupil
DIFFERENTIAL DIAGNOSIS
OF WHITE PUPIL
Retinoblastoma
Causes of White Pupil
DIFFERENTIAL DIAGNOSIS
OF WHITE PUPIL
Toxocariasis
Causes of White Pupil
DIFFERENTIAL DIAGNOSIS
OF WHITE PUPIL
Coat´s disease
Causes of White Pupil
DIFFERENTIAL DIAGNOSIS
OF WHITE PUPIL
Retinopathy of Prematurity
Causes of White Pupil
DIFFERENTIAL DIAGNOSIS
OF WHITE PUPIL
Retinal detachment
Causes of White Pupil
DIFFERENTIAL DIAGNOSIS
OF WHITE PUPIL
Coloboma
Causes of White Pupil
DIFFERENTIAL DIAGNOSIS
OF WHITE PUPIL
Retinal dysplasia
Causes of White Pupil
DIFFERENTIAL DIAGNOSIS
OF WHITE PUPIL
Norrie´s disease
Retinoblastoma
Retinoblastoma is the most common intraocular
tumor of childhood, accounting for 1% of childhood
cancer deaths in the United States and 5% of
blindness in children
The incidence is 1 in 15,000 to 1 in 20,000 live births
Overall mortality from retinoblastoma decreased from
95% a century ago. With modern diagnostic and
therapeutic advances, the mortality rate from
metastatic or recurrent retinoblastoma has been as
low as 5%
Retinoblastoma
The disease is bilateral in approximately 40% of
cases
The average age at diagnosis is 18 months and 90%
of patients are diagnosed before the age of 3 years
Retinoblastoma
Less than 10% of retinoblastoma have a family
history of the disorder, 90% of cases are sporadic
Of the sporadic cases, the responsible mutation is in
a germ cell in 25% of cases and in a somatic cell in
75% of cases
GENETICS
Located chromosome- 13q14
May be heritable or non-heritable
Retinoblastoma results from malignant
transformation of primitive retinal cells before final
differentiation
As these cells disappear in the first few years of life,
the tumour is seldom seen after 3 years of age
GENETICS
Heritable (germline) accounts for 40% of cases
One allele of RB1 (a tumour suppressor gene) is mutated in
all body cells
The mutation is transmitted in 50% but because of
incomplete penetrance only 40% of offspring will be affected
If a child has heritable retinoblastoma, the risk to siblings is
2% if the parents are healthy, and 40% if a parent is
affected
About 15% of patients with hereditary retinoblastoma
manifest unilateral involvement
Non-heritable (somatic) accounts for 60% of cases
Unilateral, not transmissible and does not predispose the
patient to second non-ocular cancers
RETINOBLASTOMA
CLINICAL MANIFESTATIONS
Leukocoria (60%)
Strabismus (20%)
OTHER- Uveitis, Orbital cellulitis, Hyphaema,
Heterochromia, Glaucoma, Buphthalmos
Presentations of Retinoblastoma
• Leukocoria - 60%
• Strabismus - 20% • Secondary glaucoma
• Anterior segment invasion • Orbital inflammation • Orbital invasion
Advanced Endophytic Retinoblastoma
Friable white mass
Fine surface blood vessels
Cottage cheese appearance
Vitreous seedings
Exophytic Retinoblastoma
Multilobulated white mass with
overlying retinal detachment
May be difficult to
visualize through deep
detachment
Ultrasound
CT diagnosis of retinoblastoma
Calcification
• Optic nerve involvement
• Orbital and CNS extension
• Pinealoblastoma
Diagnosis
Biopsies are not usually done to diagnose retinoblastoma
because
It can be recognized with great accuracy just by examination
A biopsy cannot be done easily without harming the eye
risks spreading the cancer cells
Poor Prognostic Factors
Optic nerve involvement
Choroidal invasion
Large tumour
Anterior location
Poor cellular differentiation
Older children
MANAGEMENT
Genetic Counselling
Treatment of small (3 mm diameter) tumours
Photocoagulation
Cryotherapy
Chemotherapy
Medium sized (upto 12 mm) tumours
Chemotherapy
External beam radiation
Large tumours
Chemotherapy
Enucleation
Treatment
Advantages
Disadvantages
Photocoagulation (Laser Therapy)
The laser beam focuses on the
cancerous tumor, cuts off blood
supply to the tumor and shrinks it.
Depending on the size of the tumor,
chemotherapy may be needed for
larger tumors that cannot be shrunk
just by laser.
Cryotherapy (Freezing Treatment)
The tumor is frozen and thawed
several times by a cold gas and this
causes the tumor to shrink.
The tumor will leave a pigmented scar
and the eye lid will swell for a couple
of days.
Chemotherapy
After the extensive cycles of chemo,
the cancer cells are reduced, thereby,
shrinking of the tumor.
There are several cycles, and there is
an IV port necessary to draw blood,
and inject the drugs.
Enucleation
This is removal of the eyeball and the
tumor is extracted when no other
option is possible due to the size of
the tumor.
The whole eyeball is removed with
the attendant problems of
anophthalmic socket.
Treatment
Extraocular extension
Chemotherapy
Radiotherapy
Metastatic Disease
High dose chemotherapy
Intra-thecal chemotherapy
Total body radiotherapy
Follow-up
Heritable Retinoblastoma patients can
develop recurrences and need to be
followed up regularly
Examine the patients every 6 months till
the age of 5 years and then annually till
the age of 10 years.
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