MANAGEMENT OF NYSTAGMUS From DrShashank Ranade DNB DO DOMSFCPSFICOUK Fellow Pediatric Ophthalmology Strabismus amp Ocular motility disorders International Guest Speaker UK ID: 218655
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Slide1
NEW AVENUES IN MANAGEMENT OF NYSTAGMUS
From
Dr.Shashank
Ranade
DNB, DO, DOMS,FCPS,FICO(UK)
Fellow, Pediatric Ophthalmology, Strabismus & Ocular motility disorders
[International Guest Speaker, UK]
RANADE SUPER-SPECIALITY EYE CENTRE
Mumbai
Expert panelist talk given at ALL INDIA OPHTHALMOLOGICAL SOCIETY MEET
held at KOCHI, February 2012
Slide2
Financial DisclosureI hereby declare that I don’t have any financial interests in any of the products or procedures mentioned in the forthcoming presentationSlide3
Nystagmus Work-upHistory taking- Onset, consanguinity and family history
Vision assessment
- Dilated refraction
Slit lamp examination
- iris
transillumination
defects ?
Fundus
examination
- Optic nerve or retinal pathologies ?
Eye Movement recordings
/ EOG / ENG
ERG &
pVEP
-
CSNB, Cone
dyst
, Ocular albinism, ON disorders
MRI/ CT Scan
and Neurologist opinion -suspected central/sub-cortical causes
Genetic analysis
-FRMD7 in CIN Slide4
EYE MOVEMENT RECORDINGSElecto-oculography (EOG)
Infrared reflectance (IR)
Scleral
search coil
Video-
electronystagmography
( VENG)-
Latest & most preferred choice
amongst all. Good saccadic resolution and linearity for testing saccades and pursuit, less noisy Slide5
Various treatment modalities available PRISMSOPTICAL METHODS
SOMATOSENSORY / AUDITORY FEEDBACK
ELECTRONIC METHODS Fields in which newer
PHARMACOTHERAPY avenues have developed
SURGERY
GENE THERAPYSlide6
Clinical division of treatment optionsSlide7
OLDER- LESSER PRACTICED TREATMENT OPTIONSSlide8
PRISMS Used in 3 scenario’s-
Pre-surgical evaluation purpose
Congenital Nystagmus
which gets suppressed while viewing near targets- we use 7 D BO prisms
Nystagmus with altered head postures-
Amount of prism required ( > 30 pd ), hence it obscures functional vision , are
cumbersome and cause chromatic aberration.
Dell’Osso
LF .Developments of new treatments for congenital nystagmus, Ann N Y
Acad
SciSlide9
OPTICAL METHODS More useful in Acquired Nystagmus of Neurological type
.
It
Stabilises
the image on the retina through
high convex specs
coupled with
high negative power CL ( RGP, PMMA).
Limitations
-
Disables all eye movements, works
monocularly
and in stationary state only
Field of view -limited
Difficult to handle
Refinement of an optical device that stabilizes vision in patients with nystagmus,
Yaniglos
SS, Leigh RJ,
Optom
Vis
Sci
, 1992,June, 69 ;447-50Slide10
AUDITORY/SOMATOSENSORY STIMULI & BIOFEEDBACK METHODSuppression via trigeminal afferents by using a contact lens over cornea
or
auditory stimuli over forehead
or
acupuncture over neck muscles
and has been primarily found with some effects in CIN.
Biofeedback has not been reported to be useful.
Dell
Osso,Tracis,Abel,Erzurum
-Contact Lens in congenital
nystagmus,Clin
Vis
Sci
1988 ; 3: 229-32
Sheth,Dell
Osso,Leigh,Van
Doren
-The effects of afferent stimulation on congenital nystagmus
foveation
periods. Vision Res 1995 ; 35 : 2371-82Slide11
ARTIFICIAL DIVERGENCE SURGERYAim - induce
exophoria
by
bi- medial rectus recessions or recess-
resect
procedure
which in turn the patient overcomes by exerting
fusional
convergence
The former is useful in
Congenital nystagmus
which dampens on convergence while the later in
AHP
cases
Sedler
S,
Shallo
-Hoffman J,
Muhlendyck
H. Die
Artifizielle
-
Divergenz
-Operation
beim
kongenitalen
Nystagmus.
Fortschritte
Ophthalmol
1990; 87: 85-9
.
Zubcov
AA, Stark N, Weber A,
Wizov
SS,
Reinecke
RD. Improvement of visual acuity after surgery for nystagmus. Ophthalmology 1993;100: 1488-97
Kestenbaum
and artificial divergence surgery for abnormal head turn secondary to nystagmus. Specific and nonspecific effects of artificial divergence, Graf. M, Strabismus, 2002 ; June; 10(2): 69-74
.Slide12
BOTOX 25 U of
Botulinum
Toxin A Injection is injected
directly into the
retrobulbar
space.
Used in : Acquired Nystagmus
( Post CVA
)-
reduces
oscillopsia
and improve visual acuity
Effect is short lived (3 to 6 months approx),
diplopia
and
ptosis
Might need to cover the other eye to prevent ‘competition/
diplopia
’
Helveston
EM,
Pogrebiank
AE: Treatment of acquired nystagmus with
botulinum
A toxin. Am J
Ophthalmol
, 106:584, 1988.
Lennerstrand
G,
Nordbo
OA,
Tian
S, et al: Treatment of strabismus and nystagmus with
botulinum
toxin A.
Acta
Ophthalmol
Scand 76:27, 1998
Ruben ST, Lee JP, O’Neill D, et al: The use of
botulinum
toxin for treatment of acquired nystagmus and
oscillopsia.Ophthalmology
101:783, 1994.Slide13
OLDER – WIDELY PRACTICED TREATMENT OPTIONSSlide14
HORIZONTAL RECTUS MUSCLE RECESSIONS
Maximal recession
of all 4 horizontal muscles
i.e
, as high
BMRc
of 10 mm &
BLRc
of 12 mm
First suggested by
Briti-Bagolini
(1960) but revived by Von-
Noorden
-
Helveston
(1991)
Not only
decreases nystagmus intensity
and
improve visual acuity
but also
addresses strabismus and head posture issue effectively after thorough surgical planning.
The effect of horizontal rectus muscle surgery on clinical and eye movement recording indices in infantile nystagmus syndrome,
Bagheri
et al, Strabismus, 2010,June, 18(2) ; 58-64
Vertical rectus muscle surgery for nystagmus patients with vertical abnormal head posture,
Yang
MB,Archer
et al, J AAPOS, 2004,Aug ; 8 (4), 299-309Slide15
SOURCE-
The effect of bilateral horizontal rectus recession on visual acuity, ocular deviation or head posture in patients with nystagmus,
BagheriA
,
Farahi
A,
Yazdani
,
J AAPOS, 2005, Oct, 9(5), 433-7Slide16
RECESS- RESECT PROCEDURES1953, Anderson and
Kestenbaum
independantly
suggested them. Anderson had mentioned about recession of horizontal
rectii
,While
Gotto
had suggested resection,
Kestenbaum
came with idea of operating all the 4 muscles (5mm)
Parks modified it (5,6,7,8) & Calhoun-Harley -Nelson ‘Augmented’ it.
The surgery not only
shifts the eye to null position
to correct AHP but also improves
nystagmus
waveforms
and
broaden the null zone
Anderson JR. Causes and treatment of congenital eccentric nystagmus. Br J
Ophthalmol
1953;37: 267-80.
Kestenbaum
A. Nouvelle opération du nystagmus. Bull Soc
Ophthamol
Fr 1954
Parks MM. Congenital nystagmus surgery. Am
Orthopt
J 1973;23: 35-9
Slide17
FIG 1. Comparison of preoperative (A) and 3 months postoperative (B)
electronystagmogram
showing shift of null position from 30° right gaze
preoperatively to primary position after augmented Anderson procedure
FIG 1
-Prospective Clinical Evaluation of Augmented Anderson Procedure for Idiopathic Infantile Nystagmus ,
Pradeep
Sharma,
Vimala
Menon
,
JAAPOS,Aug
2006, 10 (4), 312-317
FIG 2
- Improvement in Visual Acuity Following Surgery for Correction of Head Posture in Infantile Nystagmus Syndrome
Vijayalaxmi
, A Kumar, J POS, Nov 2011,48 (6), 341-346Slide18
HEAD POSTURE CORRECTION SURGERIESSurgery
Indication
What is
done ?
Kestenbaum
Head
turn
Bilateral 5mm recess-
resect
of hor.
recti
Augmented Anderson’s
Head Turn
Yolk muscle
recess ( MR-9, LR-12 )
Classic
Parks
Head turn
upto
30 deg
5,6,7,8
Rule
Aug
Kestenbaum
/
Classic Plus
(Calhoun-Harley)
Head turn above 30 deg
Necessary
augmentaions
of 40 % and 60 % required ( for 40 and 45 deg
resp
)
Vert
Kestenbaum
/
Parks
Chin elevation/depression
Bilateral recess-
resect
of SR & IR
Torsional
Kesten
Nyst
with Head tilt
SO & IO surgeries
Decker’s
Same
as above
Vertical transposition of horizontal
recti
Spielmann’s
Same as above
Surgical slanting
of insertion of all 4
recti
Von
Noorden’s
Same
as above
Horizontal transposition of Vertical
rectiSlide19
PHARMACOTHERAPY Slide20
Pharmacology in NystagmusName of the drug
Mode of action
Preferred
drug of choice
Gabapentin
&
Baclofen
GABA
receptor
agonists
Acquired
pendular
nystagmus
Memantine
NMDA receptor
antagonist
Congenital
Idiopathic Nystagmus
4-Aminopyridines
K+ channel blocker
Vertical upbeat-
downbeat nystagmus
Clonazepam
Benzodiazapine
/ GABA a receptor agonist
Carbamazepine
Na+
channel blocker
Sup Oblique
Myokimia
Sodium
valproate
Na+ channel blocker & GABA
agonists
Pendular
nystagmus
Acetozolamide
&
Brinzolamiode
Carbonic
anhydrase
inhibitor
Infantile
Nystamus
Benztropine
&
Trihexphenydyl
Anti-Cholinergic
Oculopalatal
tremor
Propranolol
B-
Blocker
OpsoclonusSlide21
NEWER- WIDELY PRACTICED TREATMENT OPTIONSSlide22
BACLOFENUseful in- Acquired
Pendular
Nystagmus ( esp. post
fossa
tumors and Post MS)
Recommended dosage schedule
- 5 -10 mg TDS
Visible changes noted
- reduced amplitude of horizontal
pendular nystagmus ( 70 % times ), subjective improvement of
oscillopsia
( 45 % times ) and visual acuity improvement ( 35 % times )
Side effects
- Drowsiness(63%),dizziness (15%), Nausea (12%)
Effects of
baclofen
on upbeat and downbeat
nystagmus,M
Dietrich, A
Straube
et al, J of Neurology, neurosurgery and Psychiatry, 1991 ;54 :627-32Slide23
CASE REPORT
26 yr old, male with h/o horizontal
diplopia
and dizziness since 2 weeks
Confirmed to have right INO with upbeat nystagmus
MRI -
Hyperintense
area in right midbrain
tegmentum
and anterior
cerbellar
vermis
s/o of inflammatory plaque
EEG and evoked potentials were normal
Introduced on 5mg TDS dose of
baclofen
Decrease in nystagmus intensity in primary , right , left , up and down gaze
was noticed.Slide24
GABAPENTINUseful in- Acquired
Pendular
–Jerk
Nystagmus
(esp. Post MS, Post ocular pathology) and CIN
Recommended dosage schedule
- 300 – 800 mg TDS
Visible changes noted
- reduced amplitude of horizontal
pendular
nystagmus ( 95 % times ), subjective improvement of
oscillopsia
( 60 % times ) and visual acuity improvement ( 35 % times )
Side effects
- Fatigue, dizziness, emotional and behavioral problems in children
The effects of
gabapentin
and
memantine
in acquired and congenital nystagmus : a retrospective study, T
Shery
, I
Gottlob
, Br J O, 2006 ; 90: 839-843
Gabapentin
but not
vigabatrin
is effective in acquired nystagmus in multiple sclerosis, F
Bandini
, E
Castello
et al, Journal of Neurology Neurosurgery Psychiatry, 2001; 71 : 107-11Slide25
CASE REPORT
60 yr old, male , K/C/O Multiple sclerosis
Presented with elliptical
pendular
nystagmus
BCVA -OD 6/24, OS 6/60.
Patient put on oral
gabapentin
. Started on 300 mg TDS and since the patient
was able to tolerate with inadequate response the dosage was further
increased to 800 mg TDS.
BCVA improved in OD to 6/12 OS to 6/18.
Nystagmus amplitude also showed 50 % improvement.
Now almost 6 years he is still on
gabapentin
with good tolerance and
consistent response.
After
Gabapentin
Before
Gabapentin
RIGHT EYE
LEFT EYE
Source
- The effects of
gabapentin
and
memantine
in acquired and congenital nystagmus : a retrospective study, T
Shery
, I
Gottlob
, Br J O, 2006 ; 90: 839-843Slide26
NEWER- FUTURE TRENDSSlide27
MEMANTINEUseful in- Congenital idiopathic nystagmus, Acquired
pendular
Nystagmus ( even those refractory to
gabapentin
)
Recommended dosage schedule
- 10 -20 mg BD
Visible changes noted
- reduced amplitude of horizontal
pendular
nystagmus ( 70 % times ), subjective improvement of
oscillopsia
( 45 % times ) and visual acuity improvement ( 35 % times )
Side effects
- Dizziness(7%), headache (6%), confusion (6%), constipation(5%)
The effects of
gabapentin
and
memantine
in acquired and congenital nystagmus : a retrospective study, T
Shery
, I
Gottlob
, Br J O, 2006 ; 90: 839-843Slide28
Memantine dosage schedule (Source- Dept of Ophthalmology, Leicester Royal Infirmary ,England)Slide29
CASE REPORT
65 yr old, male with c/o
oscillopsia
, ataxia, hyper-
reflexia
of right
extremities
MRI showed plaques
CSF confirmed the same
Diagnosed with MS
Started on
gabapentin
300 and then 800 TDS with poor response
Patient was shifted to
memantine
10 mg TDS and showed a spontaneous
improvement in nystagmus intensity.
RIGHT EYE
LEFT EYE
Gabapentin
Memantine
AFTER TREATMENT
BEFORE TREATMENT
Source
- The effects of
gabapentin
and
memantine
in acquired and congenital nystagmus : a retrospective study, T
Shery
, I
Gottlob
, Br J O, 2006 ; 90: 839-843Slide30
4- AMINOPYRIDINESA latest study by Strupp
et al established the role of 4-Aminopyridines and 3,4-diaminopyridines in
Upbeat nystagmus
secondary to any lesion between pathway from vestibular to
oculomotor
nuclei
Reduction in
oscillopsia
and
improvement in upward smooth pursuit
movement during attempted fixation in daylight ( abolished in darkness !)
Dosage
used was- 10 mg OD with no documented side
efffects
Probable
mode of action
is via increased excitability of
cerebellar
purkinje
cells from K+ channel blockade
4-aminopyridine restores visual ocular motor function in upbeat nystagmus ,
S Glasauer, M Strupp et al, Jour.
Neurol
Neurosurg
Psychiatry 2005;76:451–453
.Slide31
Electronic methods Device uses infrared sensor guided measurement of eye movements and feeding the same to a phase locked loop
/
adaptive filters
which generates an electric signal which in turn
rotate the riley prisms synchronous
with the nystagmus and through which the person views the world.
In future we might have specs which uses this miniature principle to cancel out the visual effects of pathological nystagmus.
Application of adaptive filters to visual testing and treatment in acquired
pendular
nystagmus, Ryan M. Smith, John S. Stahl, Journal of Rehabilitation, Research &
Development,Vol
41,June 2004, 313-324
Prospects for Treating Acquired
Pendular
Nystagmus with Servo-Controlled Optics, John Stahl et al, Invest
Ophthal
Vis
Sci
, 2000, Apr, 41(5), 1084-90Slide32
Prototype electronic device
Infrared device
Prism assembly
Acuity cardSlide33
T & R (Tenotomy & Resuturing)
Principle
- Operating on the tendon where the
Proprioceptive
feedback loop
for ocular-motor control is located.
Method
- Surgically detach the muscles from the globe and suture them back to their original insertions without resection or recession
Holds lots of promise for CIN where AHP is not an issue
There are group of people who don’t believe in and find it contentious
Improves
NAFX (
eXpanded
Nystagmus
Acuity Function)
- an indicator of target
foveation
, fastens target acquisition time and also reduce
oscillopsia
.
.
Dell'Osso
LF,
Hertle
RW, Williams RW, Jacobs JB. A new surgery for congenital nystagmus: effects of
tenotomy
on an
achiasmatic
canine and the role of
extraocular
proprioception
. J AAPOS 1999;3: 166-82
Hertle
RW,
Dell’Osso
LF,
FitzGibbon
EJ, Yang D, Mellow SD. Horizontal rectus muscle
tenotomy
in patients with infantile nystagmus syndrome: a pilot study. J AAPOS. 2004;8:539-548Slide34
Source- Effects of tenotomy on patients with infantile nystagmus syndrome, Wang, Dell Osso et al, JAAPOS,2006,10: 552-560Slide35
Simple Augmented Tendon Suture ( ATS) No
tenotomy
is required.
3 cross sword sutures with 6-0
vicryl
are placed in the tendon towards the
myotendinous
junction,not
suturing the globe
Probable mode of action- ischemia, irritation and scarring which
would act through the
proprioceptive
loop. It causes relaxation of the
resting muscle /steady state
innervation
and puts it on lower portion of
length- tension curve.
Two hypothetical Nystagmus procedures : Augmented
Tenotomy
and Reattachment and Augmented tendon suture ( Sans
Tenotomy
), Dell’
Osso
, J
Pediatr
Ophthalmol
Strabismus, 2009;46:337-344Slide36
Split Tendon, ATS method
As the name suggests you need to do a tendon split along the length and then pass the sutures on either side taking care of the vascular arcades.
No concrete evidence has yet been established about this procedure
Its efficacy needs to be established and is just a hypothesis in current scenario
Two hypothetical Nystagmus procedures : Augmented
Tenotomy
and Reattachment and Augmented tendon suture ( Sans
Tenotomy
), Dell’
Osso
, J
Pediatr
Ophthalmol
Strabismus, 2009;46:337-344Slide37
GENETICS IN NYSTAGMUSSlide38
GENE THERAPYApplicable in SENSORY DEFICIT NYSTAGMUS secondary to retinal pathologiesApplied to the retina to correct genetic deficits that impair vision directly and may facilitate the development of nystagmus
E.g
- RPE65 gene deficiency in
Leber’s
Congenital
Amaurosis
Achromatopsia
Moorefields
hosp performed
recombinant adenovirus vector
guided delivery of missing gene
in 3 patients
Maguire, A. M.,
Simonelli
, F et al. (2008). Safety and efficacy of gene transfer for
Leber's
congenital
amaurosis
The New England journal of medicine, 358(21), 2240–2248.
Bainbridge, J. W. B., Smith et al. (2008). Effect of gene therapy on visual function in
Leber's
congenital
amaurosis
The New England journal of medicine, 358(21), 2231–2239Slide39
GENETIC ANALYSIS & COUNSELLINGIndividual cases- History taking and thorough documentation of family tree will help us know the
mode of transmission, associated conditions
and
penetrance
.
Helpful in CIN- FRMD7 gene mutation, if documented then its known to have better vision, lesser AHP issue and better prognosis
Genetic analysis provides
scope for research
, which might turn a milestone for gene therapy in future
Phenotypical
characteristics of idiopathic infantile nystagmus with and without mutations in FRMD7,
Gottlob
I,
Shery
et al, Brain (2008), 131, 1259-1267Slide40
SOCIAL ISSUESNeed extra help at schoolPositioning
:
Front benches
of classroom to match AHP which will improve visual acuity, teachers need to adopt
bold writing
, high
contrast boards
Extra-curricular activities-
Avoid sports requiring fine vision i.e., ball games. Instead swimming can be preferred
Carrier guidance
- Prefer visually less demanding professions
Personality development workshops
Helpline / Networking
-
In India we don’t have any helpline like NN (Nystagmus Network) in Europe
http://www.nystagmusnet.org
/
In US they have the ANN ( American Nystagmus Network)
http://nystagmus.org/
The main intent of these sites/ networks is to improve the quality of life for all persons and families affected by nystagmus, through organized community support, education and public awarenessSlide41
Thank You