SEPTO-OPTIC DYSPLASIA - Statewide Vision Resource Centre

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Septo-optic Dysplasia (SOD)
&/Or Optic Nerve Hypoplasia
(ONH)
Geoff Bowen, Psychologist
Statewide Vision Resource Centre
Born blind and probably autistic, Thomas Green
Wiggins was known as Blind Tom. He sustained
a career that spanned 50 years and performed
for all manner of distinguished critics and fans,
including Mark Twain, and he was the first
African-American to perform at the White House.
Did he have SOD/ONH?
Biography of Blind Tom by Australian writer
Deirdre O'Connell
Reference of Note
Texas School for the Blind Texas Focus:
Learning From Near to Far
Septo-Optic Dysplasia/Optic Nerve
Hypoplasia & Autism Spectrum Disorders
June 10, 2010 Terese Pawletko, Licensed
Psychologist/Certified School Psychologist
Portsmouth, NH
SOD: Definition
• SOD previously termed de Morsier syndrome,
was first described by Reeves in 1941 as an
absence of the septum pellucidum in association
with optic nerve abnormalities.
• Variable combination of midline forebrain
abnormalities, eye abnormalities and pituitary
abnormalities.
• 2/3 features to make the diagnosis:
− Optic nerve hypoplasia
− Absence of the septum pellucidum
− Thinning of the corpus callosum
− Pituitary hormone deficiency
(added by Hoyt WF, Kaplan SL, Grumbach MM, et al. Septo-optic
dysplasia and pituitary dwarfism. Lancet. 1970;1:893–894. )
• “SOD can present at birth in association with multiple
congenital abnormalities or much later on when growth
failure occurs in a child also noted to have visual
abnormalities (although not necessarily as may just
have growth failure with mild undetected visual
abnormalities). The child may present with strabismus,
nystagmus, or other visual abnormalities. In the
majority of cases, the earlier the diagnosis is made the
better the outcome, as untreated hormonal
abnormalities place an additional neurodevelopmental
burden on a child already compromised by visual
impairment, and also place the patient at risk of
hypoglycaemia, adrenal crises and consequently
death.” Septo-optic dysplasia Emma A Webb and Mehul T Dattani see reference
1
below)
On The Increase!?
• ONH was very rare with only 35 cases noted in
the English language medical literature before
1970.
• ONH is on the increase - today considered the
most common single cause of congenital
blindness in the industrialized world.
• Swedish study (1997) an incidence of 6.7 out of
100,000 births or about 1 in 15,000 births.
On The Increase!?
• ONH = leading cause of childhood visual
impairment in the US and Europe – 12% of
children with VI (Blohme et al, 200, Hatton et al,
2007) or 1/10000 chn < 16 years of age (Patel
et al 2006; Garcia-Filion et al 2008).
• Sixfold increase from 1977 estimate of
1.8/100,000 (Jan et al 1977)
On The Increase!?
• ONH blindness is more common today than
blindness due to retinopathy of prematurity
(ROP).
• Now the most common cause of blindness in
children in the USA
• Outdistancing many other birth defects which
are currently more familiar, including congenital
muscular dystrophy and Williams Syndrome.
On The Increase!?
• On our books 14 SOD/ONH and 24 ONH in
2009
• 11 and 32 in 2012.
• NB: To date, there is no pre-natal screening to
detect ONH blindness.
SOD or ONH
• The term Septo-Optic Dysplasia is slowly losing
favour with physicians and researchers because
the presence or absence of the septum
pellucidum does not seem to be a defining
aspect of the diagnosis. ONH is now the
preferred term.
• Some individuals can have an absent septum
with no negative consequences.
• Absence of SP in Garcia-Filion et al 2008
unrelated to development (was associated with
CCH)
• Absence of SP (with no pituitary or cerebral
abnormalities) was associated with “normal
neurodevelopmental parameters” in language, IQ,
behavioral functioning - “neurodevelopmentally
and endocrinologically inconsequential unless
accompanied by posterior pituitary ectopia or
cerebral hemispheric abnormalities” (p. 70, Brodsky &
Glazier 1993)
• Optic nerve hypoplasia (ONH) has been
described as an increasingly prevalent cause of
congenital blindness. Its association with
hypopituitarism and absent septum pellucidum
has been recognized for more than 40 years as
"septo-optic dysplasia" or "de Morsier
syndrome." More recent studies have suggested
that these associations are independent of one
another (Borchert, 2012).
Forebrain Abnormalities
• In 75-80% of patients
• Absence of septum pellucidum
• Absence of corpus callosum
• Cerebellar hypoplasia
• Schizencephaly
Consequences Of Forebrain Anomalies
• Fits
• Behavioural difficulties
• Learning difficulties
• Developmental delay
• Hemiplegia
Optic Nerve Hypoplasia
• Unilateral/bilateral
• Bilateral commoner
• Associated with anopthalmia/micropthalmia
• Visual impairment variable - complete to
compensated
VISUAL FEATURES
• Optic nerve and chiasm hypoplasia (decreased #
of fibers). Clinical signs: small optic disc, double
ring sign and abnormal retinal vasculature.
• Can affect one or both (80% of ONH, impact can
be asymmetrical) eyes.
• Visual acuity (may be near normal to NLP); high
refractive errors (80% of bilateral in legally bl.
range.)
VISUAL FEATURES
• Note: degree of visual impairment correlated
with presence of severe pituitary anomaly (Riedl
et al 2008)
• May have field restrictions
• May have color blindness
• Nystagmus (may be ‘wandering’ if NLP)\
VISUAL FEATURES
• Strabismus
• May lack of depth perception if amblyopic
• May have mild photophobia (and squint, lower
their head, avoid light by turning away, resist
participating in outdoor activities)
• Microphthalmia, colobomas of the
iris/choroids/retina
Pituitary Gland
• Develops from the oral cavity in the embryo and
the brain (hypothalamus)
• 5 different cell types in anterior pituitary
producing 6 different hormones
• Secretion of hormones regulated by
hypothalamus
Pituitary Hormones
•
•
•
•
•
•
•
•
•
Adrenocorticotrophic Hormone (ACTH)
Thyroid Stimulating Hormone (TSH)
Lutenising Hormone (LH)
Arginine vasopressin (ADH)
Oxytocin
Follical Stimulating Hormone (FSH)
Growth Hormone Deficiency (GHD)
Gonadotrophic Releasing Hormone (GnRH)
Multi Pituitary Hormone Deficiency (MPHD)
Anterior Pituitary Gland
• Growth hormone: growth and helps maintain
normal blood sugar levels in children; increases
bone strength, muscle mass and decreases fat
mass and heart disease in adults.
• ACTH: regulates production of cortisol and
androgens from adrenal glands; cortisol
essential for normal well-being and to fight
stress and infection.
Anterior Pituitary Gland
• Prolactin: important for lactation, ?immune
system
• FSH, LH: important for puberty and fertility; LH
important for normal development of males and
for descent of testes into scrotum
• TSH: important for regulation of thyroid gland
and thyroxine production
Posterior Pituitary Gland
• Vasopressin: important for normal fluid balance retains water by controlling reabsorption of
water in kidney tubules
• Oxytocin: important for parturition (birth) and
ejection of milk
Pituitary Hormone Deficiency
• GH: poor growth with eventual short stature,
possibly increased incidence of myocardial
infarction.
• Prolactin: no lactation.
• ACTH: low cortisol leading to low blood sugar,
lethargy, inability to fight stress and infection,
low blood pressure, low sodium level in blood,
collapse
Pituitary Hormone Deficiency
• FSH, LH: inadequate sexual development in
males, lack of puberty, lack of fertility.
• TSH: lack of thyroxine with slowness, cold
intolerance, constipation, growth failure, mental
retardation if not picked up early.
• Vasopressin: diabetes insipidus with excessive
urinary output.
Complexity Of Hypothalamo-pituitary
Development
• Early puberty: can be explained on basis of
hypothalamic involvement
• Occasionally mixed involvement of
hypothalamus and pituitary
Clinical Features Of SOD
• Conjugated jaundice
• Neurological features
• Variable visual loss
• Impaired sense of smell
• Endocrine features
• Behavioural disturbances e.g.. Autism
• Sleep disturbance
Table Next from: Septo-optic dysplasia Emma A Webb1 and
Mehul T Dattani1 European Journal of Human Genetics (2010)
18, 393–397; doi:10.1038/ejhg.2009.125; published online 22
July 2009.
Management Of SOD
• Support from Neurologists and
Ophthalmologists: treatment of convulsions
• Mainstay of treatment: endocrine
Endocrine Replacement
• Growth hormone: daily subcutaneous injections.
• Hydrocortisone: X3 doses daily; adjustment with
illness/stress.
• Desmopressin DDAVP: nasal/oral (Minirin)
• Thyroxine
• Ethinyloestradiol/testosterone
Investigations
• MRI scan of brain
• Visual evoked responses/electro-retinogram
• Routine electrolyte measurement
• Thyroid function tests
Investigations
• Pituitary function tests:
glucagon/insulin/LHRH/TRH
• Fluid balance
Monitoring
• Evolving - new endocrine features may develop.
• Monitoring of growth rate at regular intervals.
• Monitoring through puberty.
• Regular checks of thyroid function, watch fluid
balance.
Long-term Outlook
•
•
•
•
•
•
•
Short stature
Developmental/intellectual impairment
Fits, hemiparesis etc
Impaired fertility
Visual impairment
Sleep/behavioural difficulties
Obesity
Why Do You Get SOD?
• Largely unclear
• Commoner in young mothers
• Development of pituitary gland, forebrain,
olfactory bulbs and eyes all from the same part
of the early embryo. Problems occur at 3-6
weeks of gestation
• Environment and teratogens
Why Do You Get SOD?
• “It is likely that although other genetic
abnormalities are likely to be identified in the
future, environmental factors such as drugs,
alcohol and anterior cerebral artery supply
during the neonatal period may also play a
significant role in the aetiology of SOD.”
Septo-optic dysplasia Emma A Webb1 and Mehul T Dattani
see reference above)
Genetics Of SOD
• Mutations in HESX1: Dominant or recessive.
• Occasionally, one abnormal copy of gene
carried with no phenotype in parent but child
affected.
• Number of other developmental genes may also
be involved: all extrapolated from animal
studies.
Genetics Of SOD
• Research is ongoing into the genetic aetiology
of SOD. To date, the overall frequency of
pathological genetic mutations identified in the
SOD population is low, with no mutations
identified in many familial cases, suggesting that
mutations in other known or unknown genes
may have a role in this complex disorder.
Research
• New genes involved in SOD: what is their
function?
• Why the variability in severity
• Sleep/wake cycles in children with SOD and
hypothalamic involvement and the use of
melatonin (10-18 year olds)
The following statement are NOT TRUE
according to current research:
– ONH occurs in clusters due to use of pesticides in
the environment.
– The associated midline brain anomalies have a
profound effect on the visual outcome and/or spatial
orientation of these patients.
– All mothers of children with ONH were drug users
during pregnancy.
Optic Nerve Hypoplasia Pediatric Visual Diagnosis Fact Sheet
http://www.tsbvi.edu/seehear/spring99/opticnerve.htm
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Behaviours Seen In Children With
SOD/ONH?
A comprehensive behavioural survey is yet to be
conducted. However, it seems clear that many
commonalities exist within the ONH family:
– Often have very low (or high) muscle tone. They may
go limp without warning and have to be carried.
– Show a very high degree of obsessive behaviour,
including flapping, rocking, tapping, screaming, or
chewing on a finger.
– Like to follow strict household routines and become
agitated when the routines are not followed precisely
or carried out in a particular order.
– Language and conversation is often very delayed
and scripted, and they may repeat back what words
or phrases that they hear (‘echolalia’).
– Ask the same questions over and over again, paying
attention to subtle variations in responses.
– May memorize a dialogue and attempt to engage
every new person they meet with it.
– Often extremely sensitive to sound - may cover their
ears and cry not only when sounds are loud, but
because they find it difficult to adjust to overlapping
sounds or to sounds which shift in register.
– Often show tactile defensiveness and oral
defensiveness. Many of these traits diminish over
time.
– Some children have extraordinary memories, and
can quickly memorize songs and stories. They may
recall these stories, word for word, months or years
after they have first heard them (and with accurate
intonation and inflection).
– Some children have a very high interest and ability
with music (savant?)
– Though not all respond to music, many parents of
ONH children notice the value of music as a way of
stimulating conversation with their children, or in
smoothing over difficult social or environmental
transitions.
– ONH behaviours are sometimes puzzling, and
parents are never quite sure what might set their
child off or to what the child is responding.
Do children with ONH have Autism?
• 20% or more of children with ONH are believed to
have some autistic-like symptoms.
• “ONH autism” is a controversial area. Many parents
of ONH children have recognized that their children
do not fit the classical definitions or models of
autism, and have adapted therapies to suit their
specific educational and therapeutic needs.
Do children with ONH have Autism?
• Some ONH parents accept the “autistic” label,
some accept it reluctantly (in order to gain
access to therapies which might not otherwise
be available), and still others reject it outright.
• All agree that ONH behaviours needs to be
understood on their own terms.
Autism Spectrum Disorders
• The DSM – IV is the current basis for diagnosis.
• The following gives the impairments that exist in
three areas.
However, the criteria from the DSM-IV are
provided to give professionals a consistent basis
for determining diagnosis. However, these
criteria alone are not sufficient for diagnosis.
The practitioner uses a broad range of
information and clinical experience to determine
the presence of an autistic spectrum disorder.
Likewise, autism checklists have limited
usefulness and should not be the basis for
diagnosing autistic spectrum disorder.
Impairments in Communication:
– Delay in, or total lack of, the dev’t of spoken lang.
(not attempt to compensate thru alternative modes
of communication such as gesture or mime)
– Individuals with adequate speech, have marked
impairment in the ability to initiate or sustain a
conversation with others; may have problems
understanding & using language flexibly verbal and
nonverbal forms of communication);
– Exhibit stereotyped and repetitive use of language or
idiosyncratic language
– Lack of varied, spontaneous make-believe play or
social imitative play appropriate to developmental
level
• Impairments in the ability to form and
maintain social relationships, as manifested
by at least 2 of the following:
– Marked impairment in the use of multiple nonverbal
behaviors such as eye-to-eye gaze, facial
expression, body postures, and gestures to regulate
social interaction
– Failure to develop peer relationships appropriate to
developmental level
– Lack of spontaneous seeking to share enjoyment,
interests, achievements w/other people (e.g., lack of
showing, bringing, pointing out objects of interest)
– Lack of social or emotional reciprocity at level
commensurate with their cog./dev’l level
• Restricted repetitive and stereotyped
patterns of behavior, interests & activities,
as manifested by at least one of the
following:
– Encompassing preoccupation w/one or more
stereotyped and restricted patterns of interest that is
abnormal either in intensity or focus
– Apparently inflexible adherence to specific,
nonfunctional routines or rituals
– Persistent preoccupation with parts of objects
– Stereotyped and repetitive motor mannerisms (e.g.,
hand, finger posturing, complex whole-body
movements)
• All present prior to the age of 36 months…
What Works the Best!
From my 35 years working in schools, 30 years as a
psychologist, over 25 years working in a variety of
special settings particularly SDS’s and 21 years working
with vision impaired students, the most effective way to
assist the development, learning and quality of life of
students with a variety of disabilities (particularly
Autism) is for them to have a competent experienced
teacher(s), with clearly defined educational plan, in a
well run and well resourced school.
The icing on the cake is the school and the parents
working together!
Appropriate Educational Programming
• Each child should receive medical monitoring and
ophthalmological monitoring. Get the most
accurate measure of what the student can and
can’t see! This is critical to appropriate planning.
• There should be a comprehensive functional vision
assessment and educational assessment that
relates the child’s vision issues to the educational
strategies that need to be used.
• There should be comprehensive assessments of
language ability, cognitive ability, sensory
processing, orientation and mobility and gross
motor coordination. These will help guide
educational programming
• A child with ONH often has other conditions that
need to be considered when developing an
individual education plan.
• Get the vision needs of the child right i.e. size of
print, illumination etc.
• Get the print VS Braille issue sorted out as early
as possible.
• Get all involved with the child to understand that
Orientation and Mobility training is crucial to the
long term well being quality of life and
employability of an individual.
• A child who is easily distracted, frustrated,
disorganized, and impulsive may be helped by
predictable physical environments, dependable
daily routines, and limited distractions.
.
• Slowing the pace of activities and providing
predictable transition routines may help reduce
resistant and irritable behaviour
• If you are teaching using prompts have a plan to
remove them!
Pearls from Terese Pawletco (2010 presentation)
• I never assume that a child “knows something”
unless I’ve taught it - pre-teach, reinforce
• Sequential learners
• Children with ASD package by context
• Be aware of your language - rate, volume,
complexity and that of those around you
Pearls from Terese Pawletco (2010 presentation)
• Be aware of competing stimuli
• Less is more. Short and sweet, be concrete
• Remember to pause, allow more processing
time; don’t be quick to repeat question
• Just because he talks, does not mean he
understands
Pearls from Terese Pawletco (2010 presentation)
• Remember to pause, allow more processing
time; don’t be quick to repeat question
• Provide tangible supports – physical layout,
schedules, work systems, clearly tactually
defined activities; task cards; also supports
expressive communication (mental set
associated with them)
Pearls from Terese Pawletco (2010 presentation)
• Use visual supports (print, Braille, picture) –
write it down! Write it down, write it down!
There is “POWER in print!”
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