Download case 1 week 22 - Ipswich-Year2-Med-PBL-Gp-2

Neuro week 1
Case 1
Katherine, aged 28 years, is a previously healthy
woman who presents to you because of
blurred vision of the right eye.
She noticed this upon awakening three days
earlier. Over the next 2 days, her vision
gradually deteriorated, and she developed
right ocular pain when she moved her eyes.
There is no prior history of neurologic
symptoms and she has had no recent infection
or immunisation.
Q1 Describe/demonstrate a clinical examination of the eyes
that you would perform in your general practice rooms.
Q1 Describe/demonstrate a clinical examination of the eyes
that you would perform in your general practice rooms.
• Inspection
– Look for ptosis
– Inspect colour of slcerae:
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Yellow (jaundice)
Blue (osteogenesis imperfecta)
Blue/grey (ochronosis)
Red (iritis/scleritis/conjuctavitis/subconjunctival
haemorrhage)
– Look for exopthalmos (prominence of eyes) and
proptosis (protrusion of eyes from orbits)
– Look for corneal ulceration (fluorescein will stain
corneal ulcers)
Q1 Describe/demonstrate a clinical examination of the eyes
that you would perform in your general practice rooms.
• Cranial nerve examination (2,3,4,6):
– Visual acuity
• Test each eye with Snellen chart with other eye covered
• Glasses can be used
– Visual fields
• Without glasses, eyes of patient and examiner should be level, patient should be at
arms length
• Patient covers one eye, mirrors the examiner and both stare straight ahead
• Hat pin is brought in gradually from outstreched arm in diagonal direction
• Patient reports when pin is first sighted in peripheral vision and if it disappears
while travelling to centre of vision
• Enquire about diplopia
– Pupillary responses to light
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Shine focused light in one eye at a time
Assess direct and consensual response
Repeat these tests on other eye
Move torch in arc from pupil to pupil to test for afferent pupillary defect
Q1 Describe/demonstrate a clinical examination of the eyes
that you would perform in your general practice rooms.
• Cranial nerve examination (2,3,4,6):
– Accommodation
• Ask patient to look into distance and then at the hat pin placed 30cm from nose
• Normally both pupils constrict and eyes converge
– Eye movements
• Patient to follow hat pin with eyes only
• Use modified H pattern
• Look for failure of movement and for nystagmus
• Corneal reflex
• Fundoscopy
– Refer to ophthalmic notes
Her visual acuity is 6/24 in her right eye and 6/6
in her left eye. A right afferent pupillary
defect and a central scotoma are
present. Fundoscopic examination is
normal. The rest of her neurological
examination is normal. You involve your local
ophthalmologist who finds no intrinsic eye
pathology and agrees with your diagnosis of
optic neuritis.
Q2 Describe the pathophysiological mechanism behind this
presentation. Describe the nerve fibres involved in the
pupillary reflex. Explain the finding of an afferent pupillary
defect.
Q2 Describe the pathophysiological mechanism behind this
presentation. Describe the nerve fibres involved in the
pupillary reflex. Explain the finding of an afferent pupillary
defect.
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Right eye visual acuity poor
Right eye afferent pupillary defect
Right eye central scotoma
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These findings are most commonly due
to optic nerve pathology eg:
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Optic neuritis
Sarcoidosis
Tumour
Leber’s hereditary optic neuropathy
Nerve fibres involved in pupillary
reflex:
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Afferent – optic nerve
Efferent – occulomotor nerve
Left afferent pupillary defect
Her visual acuity is 6/24 in her right eye and 6/6
in her left eye. A right afferent pupillary
defect and a central scotoma are
present. Fundoscopic examination is
normal. The rest of her neurological
examination is normal. You involve your local
ophthalmologist who finds no intrinsic eye
pathology and agrees with your diagnosis of
optic neuritis.
Q3 Briefly discuss the clinical course and outcome. What
information can you give Katherine about the recovery of her
vision?
Q3 Briefly discuss the clinical course and outcome. What
information can you give Katherine about the recovery of her
vision?
• Recovery of vision
– Without treatment, vision begins to improve after a few weeks. Improvement can
continue over many months;
– 90 percent have 20/40 or better vision at one year
• Some chronic features:
– Persistent visual loss. Most patients with optic neuritis recover functional vision
within one year. However, on testing, deficits in color vision, contrast sensitivity,
stereo acuity, and light brightness are detectable in most patients at up to two
years
– A relative afferent pupillary defect remains in approximately one-fourth of patients
two years after presentation
– Colour desaturation
– Temporary exacerbations of visual problems during increases of body temperature
eg. hot showes, exercise
– Optic atrophy (despite return of visual acuity) occurs to some degree in most cases
of optic neuritis
Q4 What can you tell Katherine about the risk of developing
multiple sclerosis?
• ~50% of people with optic neuritis go on to
develop MS
• ~15-20% of people with MS had optic neuritis
as their first symptom
Q5 What features, if any, predict a patient's likelihood of
developing MS following a single episode of optic neuritis?
• MRI
– white matter brain lesions increase risk of developing
MS by 3x (but ~1/2 of patients with lesions on MRI
will not have developed MS 10 years later)
• Lumbar puncture
– oligoclonal bands increase risk
• Papillitis, peripapillary haemorrhage and retinal
exudates with a normal MRI brain decreases risk
of MS
One year after the episode of optic neuritis,
Katherine develops painless numbness under
her left foot, which gradually ascend to
involve the entire leg and eventually moves up
to her ribcage, with less severe numbness on
the other leg. She also complains of leg
weakness and urinary urgency, and takes time
off work.
Q6 What can you tell Katherine now about her diagnosis?
Q6 What can you tell Katherine now about her diagnosis?
• Can now be defined as MS
– Two or more episodes of symptoms
– Two or more signs that reflect pathology in
anatomically non-contiguous white matter tracts of
the CNS
• -> symptoms must last for > 24 hr and occur as
distinct episodes that are separated by a month
or more
– There is no specific investigation, but MRI/evoked
potentials/CSF abnormalities
Katherine understandably expresses concern
about what the future hold for her with a
diagnosis of Multiple Sclerosis.
Q7 What additional information can you provide about the
course of her illness?
Q7 What additional information can you provide about the
course of her illness?
•
Average number of years to death from onset of MS is 30, with life expectancy of
people with MS 5 – 10 years lower than those unaffected. MS doesn’t always
cause paralysis – Most people living with MS do not become severely disabled.
90% of those living with MS are still walking at 10 years from onset, and 75% at 15
years. Two thirds never get severely disabled although they are using walking aids
etc in later years. Those with MS are encouraged to keep working. “I have MS, MS
doesn’t have me”.
•
Not curable, not contagious, not fatal, not heritable (only 1% chance that offspring
have MS too) pregnancy is actually associated with lower frequency of relapse.
There is no special diet but increasing vigilance over good diet and exercise will
help combat some symptoms of MS like fatigue; reduced mobility can lead to
increased weight – which is not good if balance is not the best. Keeping a healthy
lifestyle will also reduce infective illness which can lead to increased weakness.
Keep cool wherever possible – don’t overdo exercise – workout hard and fast and
then have a cool down period.
•
Drug treatment aims at reducing the frequency and severity of attacks and slowing
the progress of disability.
Q8 Are there any prognostic features that might give Katherine
further information?
• Better prognosis is associated with:
– Female gender
– Relapsing – remitting subtype of MS
– Optic neuritis of sensory symptoms at onset
– Few attacks in the initial years
– Early age at onset