Transcript Nystagmus - Hubli - MM Joshi Eye Institute

Management of Nystagmus – the
Ophthalmologist’s perspective
Dr. R.R.Battu
Consultant Pediatric Ophthalmologist
Narayana Nethralaya
Bangalore
Historically
What is the presenting feature?
– Nystagmus - “Wobbly
eyes”
– Anomalous Head
Posture
– Poor vision
– Photophobia
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Informant:::
Night blindness
Oscillopsia
Vertigo
Diplopia
Head nodding
Many times a combination of the above !!
Historically
• Family history
– Poor vision
– Nystagmus
– Neurological disease
Historically
• When did this start?
– At birth or shortly thereafter [ “Congenital” or
infantile nystagmus ]
• Congenital sensory or motor nystagmus
• Congenital neurological nystagmus
• Rare variants
– PAN
– Spasmus nutans
Historically
• Medication
– Anticonvulsants
– Sedatives
– “Psychiatric medications”
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Occupation [ - and hobbies? ]
Epilepsy
Head Trauma
Neurological abnormalities……..
Craniofacial anomalies
• Is there a visual defect?
– If so, qualify and quantify
• Is this likely to be an “ Ocular nystagmus”
– Sensory defect nystagmus [ SDN ]
– Latent nystagmus [ LN/ MLN ]
Observe
• One time observation
• Multiple session observation
– Usually required in children
– Tired adults
What to Observe
• The eye
• The alignment
• The nystagmus
• Anomalous Head position
The Eye
• Evaluate refractive error
• Evaluate the anterior segment
• Evaluate the posterior segment
Visual Acuity
• Behaviour
– Eye poking
• Pre verbal child or infant
– Fix and follow
– Other techniques
• Special problems with Latent
nystagmus - Infantile Esotropia
– Fogging
– Polarised glasses – Vectograph
– Neutral density filter
– Remote occlusion
– The Spielman Occluder
The Eye
• Microphthalmos
• Obvious malformations
• AFFERENT PUPILLARY DEFECT
The Eye
• Iris
– Obvious or subtle transillumination defects
– Ocular or oculocutaneous albinism is usually a
straightforward diagnosis. The anterior
segment clues you onto the typical posterior
segment abnormalities
• The lens
– Cataract
The Eye
• Optic nerve abnormalities
– Hypoplasia
– Atrophy
– Coloboma
• Retinal abnormalities
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Albinism
Macular hypoplasia
Cicatricial ROP
Dysplasia
Coloboma
Pigmentary retinopathy
The Alignment
• Ortho, Eso or Exo?
In an infant:
Eso - Infantile esotropia with LN/MLN
Nystagmus Compensation Syndrome
Exo – Infantile exo,
many times with neuro-developmental issues
The Nystagmus
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Pendular or Jerk
Direction
Frequency and Amplitude
Variation with gaze
Variation with convergence
Variation with monocular
occlusion
• Binocular symmetric
• Binocular asymmetric
• Monocular
“How long” to “observe” ?
• Single concentrated ‘effort’ of observation of
at least 3 minutes !!!
Periodic Alternating Nystagmus
Serious neurological disease?
• Asymmetric
•
nystagmus
Monocular nystagmus
– Visual pathway
disorders !
• Vertical nystagmus
• Purely torsional
nystagmus
Evaluation
Asymmetric nystagmus
INO
Spasmus nutans
Rarely Congenital nystagmus
Parasellar tumours
Restrictive or paralytic ocular muscular disorders
Congenital Idiopathic Nystagmus
• Observation
– Most commonly horizontal
– Pendular or jerk
– Horizontal nystagmus in
vertical gaze positions [
Uniplanar ]
– Null position – Eccentric or
on near gaze
– Usually symmetric
– Fulcrum of rotation in
“apparently” asymmetric
nystagmus.
Congenital Idiopathic Nystagmus
• Typically 3 phases of development [ Dr. Robert
Reinecke]
– Phase 1- Broad triangular wave form [ 3-6 mths]
– Phase 2- low amp pendular waveform [6-24 months]
– Phase 3-Typical jerk nystagmus [24-36 months]
• Historically:
– No oscillopsia
– Invariably improves with age
Spasmus nutans
• Head nodding
• Anomalous head position
• Monocular/asymmetric nystagmus –
“ Shimmering”
• RULE OUT CNS TUMOUR [ glioma ]
Latent nystagmus/ Manifest Latent
Nystagmus
Probably the only cause of Infantile nystagmus
which does not need Electrophysiologic study or
Neuro imaging
Latent nystagmus
• Beats away from the
covered eye [ towards
the fixing eye ]
Anomalous Head Position
• Null point
– Beware PAN
– Wandering Null point
• Usually in an eccentric gaze position
• Head is positioned AWAY from the null
point
– i.e. Null point to left, face turn to right
• Mostly lateral turn, occasionally vertical
and cyclovertical head turns
Electrophysiology
• ERG, EOG and VER
• Would probably be indicated in most
situations as an initial ‘workup’
• May allow to avoid neuroimaging
Neuro imaging
• Again, would probably be required as an
initial workup, unless there is
unequivocally ophthalmic cause of
nystagmus evident on examination and
Electrophysiology
TREATMENT
• Drug treatment
• Optical treatment
• Chemodenervation
• Surgical treatment
Drug Therapy - Specific
• Pendular Nystagmus – Gabapentin and
Memantine
• PAN – Baclofen
• Superior Oblique Myokymia –
Carbemazipine, Gabapentin
Drug Therapy – Less specific
• Pendular – Valproate, Trihexyphenidyl,
Isoniazid, Cannabis
• Downbeat nystagmus – 3,4
diaminopyridine, 4 aminopyridine,
gabapentin, clonazepam, baclofen
• Any form of Nystagmus – Clonazepam,
baclofen
Optical treatment
CORRECT REFRACTIVE ERROR
Refraction in nystagmus
1. Binocular UCVA in forced pp
2. Binocular UCVA in preferred AHP
Refraction in nystagmus
1. Binocular retinoscopy with patient fixing either
in AHP or forced PP
1. Put the lenses in front of both eyes, fog one eye by
1-3 lines
2. Subjectively refract other eye
3. Repeat on the other side
4. If there is no strabismus ( orthophoric), then add
upto 7pd BO prism and -1.0DS to the prescription,
observe nystagmus and check binocular acuity
5. Repeat all steps with cycloplegia
Factors which can be improved
• Visual acuity
– VA, contrast sensitivity, colour, motion sensitivity,
gaze angle
• Anomalous Head Position
– Congenital nystagmus, acquired nystagmus,
convergence damping, adduction null in LN/MLN
• Oscillopsia
– Acquired nystagmus, decompensated congenital
nystagmus
• Hypo accommodation
• Photophobia
Refractive Correction
• In children upto 10 years, full cycloplegic
refraction
• In adults, subjective, try to push over time
if there is a difference in sub and obj
refraction
Amblyopia therapy
• May significantly decrease or eliminate
MLN …… LN
• Periods of occlusion have to be very
prolonged in patients with LN
• Alternatively fogging or penalisation may
have to be used
Optical treatment
• To direct the null point centrally
– Prisms placed with apex directed towards the
null point.
– Large power prisms may have to be used.
– Fresnels
– May degrade vision
Optical treatment
• To stabilize visual image on the retina
– High plus spectacle with high minus contact
lens[ -58 & +32 ]
– Entire 30 deg field focussed to centre of eye,
and CL refocuses to the retina.
– Image remains stable irrespective of eye
movement !!
Optical treatment
• To induce convergence
– Base out prisms bilaterally
– Induce a convergence
– Useful only if there is a convergence null
– May have to compensate with a -1.0 sph for
induced accommodation
Chemodenervation
• Botox
– 2.5 – 5 units into all horizontal recti
– Retrobulbar injection of 25 – 30 units
Chemodenervation
• Useful to reduce amplitude of nystagmus
• Has been shown to improve foveation
time and improve visual acuity slightly.
• More useful in neurological acquired
nystagmus, particularly in oculopalatal
myoclonus
• RB injection effect lasts for several weeks
Chemodenervation
• Complications include
– Ptosis
– Diplopia
– Filamentary keratitis
Electronystagmography
Nystagmovideography
Surgical principles
• Decrease the amplitude of nystagmus
– Maximal recession of horizontal muscles
– Tenotomy
• Increase foveation time
– Tenotomy
• Broaden the null zone
• Rotate the null zone
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Anderson
Goto
Kestenbaum
Parks’ modification of Kestenbaum
Augmented Kestenbaum
• 40%
• 60%
• Induce an attempt to converge
– Artificial divergence surgery
Surgery to correct AHP
Face turns - horizontal
• Anderson advocated bilateral recession
– Eg. Null zone to left, weaken levo- ‘verters’
• Kestenbaum advocated recess-recess [
pull and push]
• Park’s modification of Kestenbaum’s
– 5-6-7-8 rule [both eyes get 13 mm ]
• Very rarely corrects more than 10 -15 degrees
Surgery to correct AHP
• Augmented K-A procedure
– Classic + 40% - For > 30 deg of face turn
– Classic +60% - for > 45 deg of face turn
• Problems
– Intractable diplopia
Surgery to correct AHP
Vertical AHP
– Chin up
• IR recess – SR resect
– Chin down
• IR resect– SR recess
• Anteriorisation of IO
Patient with right horizontal gaze palsy and head turn of approximately 20° to the right (a); the same patient 1 year after
recession of right medial rectus and left lateral rectus muscles (b). Note: the patient can use his glasses more effectively.
Patient with acquired nystagmus equilibrium in upward gaze; CHP with chin-down is present (c); the same patient 1 year
after surgical weakening of both superior rectus muscles (d).
E C Campos1, C Schiavi1 and C Bellusci1.
Surgical management of anomalous head posture because of horizontal gaze palsy or acquired vertical nystagmus
Eye (2003) 17, 587–592. doi:10.1038/sj.eye.6700431
Surgery to correct AHP
Cyclovertical AHP
• As an adaptation to torsional nystagmus
• Surgery to recreate the torsional direction
‘created’ by the patient’s head tilt
• Several methods
– Strengthen or weaken obliques
– Slanting recti insertions
– Vertical recti slanting
Surgery
• Other problems
– Management of co existent strabismus with
nystagmus
– Acquiring of a new head position - PAN
– Creating a new strabismus
Surgery primarily designed to
improve vision
• Artificial divergence
– Bimedial recession
– Unilateral recess-resect to XT
• 4 – muscle retro equatorial recession
– 10 mm MR and 12 mm LR
– Ideal for PAN
– May induce an exotropia
Dell’Osso & Hertle
• Based on the principle of enthesial
proprioceptive input to nystagmus at the
insertion of the horizontal recti
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•
Dell'Osso LF. Extraocular muscle tenotomy, dissection, and suture: A hypothetical therapy for
congenital nystagmus. J Pediatr Ophthalmol Strab 1998; 35:232-3.
Hertle RW, Dell'Osso LF, FitzGibbon EJ, Thompson D, Yang D, Mellow SD. Horizontal rectus
tenotomy in patients with congenital nystagmus. Results in 10 adults. Ophthalmology 2003;
110:2097-105.
•
Hertle RW, Dell'Osso LF, FitzGibbon EJ, Thompson D, Yang D, Mellow SD. Horizontal rectus
muscle tenotomy in patients with infantile nystagmus syndrome: a pilot study. JAAPOS 2004;
8:539-48.
Summary
• Evaluation of nystagmus is
multidisciplinary
• However, it is possible to improve the
quality of life with drugs/optical
devices/surgical procedures
• No single procedure has shown to be
consistently predictive of success
• This does not mean we cannot try.
Thank you