Post on 02-Feb-2018
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Understanding Nystagmus: Understanding Nystagmus: Diagnosis, Diagnosis,
Related Disorders,Related Disorders,Treatment, andTreatment, and
ResearchResearch
MitraMitra MaybodiMaybodi, MD, MDChildren’s National Medical CenterChildren’s National Medical Center
George Washington University School of George Washington University School of Medicine and Health SciencesMedicine and Health Sciences
Washington, DCWashington, DC
NystagmusNystagmus
“All that wiggles is not nystagmus.”“All that wiggles is not nystagmus.”
DefinitionDefinition: Involuntary oscillation of the : Involuntary oscillation of the eyes, characterized by a slow phase, eyes, characterized by a slow phase, followed by a fast phase.followed by a fast phase.
Physiologic NystagmusPhysiologic Nystagmus
EndEnd--point point (eccentric(eccentric--gaze) gaze) nystagmusnystagmus
Physiologic NystagmusPhysiologic NystagmusVestibular NystagmusVestibular Nystagmus
Physiologic NystagmusPhysiologic Nystagmus
Optokinetic Nystagmus
InfantileInfantile--Onset Onset NystagmusNystagmus
Congenital nystagmusCongenital nystagmus(Infantile nystagmus syndrome*)(Infantile nystagmus syndrome*)Latent / manifest latent nystagmusLatent / manifest latent nystagmus((FusionalFusional maldevelopmentmaldevelopment nystagmus nystagmus syndrome*)syndrome*)SpasmusSpasmus nutansnutans((SpasmusSpasmus nutansnutans syndrome*)syndrome*)OthersOthers: congenital see: congenital see--saw, downbeat, saw, downbeat, upbeat, or familial vertical upbeat, or familial vertical pendularpendular
(*: Proposed by Classification of Eye Movement (*: Proposed by Classification of Eye Movement Abnormalities and Strabismus Working Group, NIH, 2001)Abnormalities and Strabismus Working Group, NIH, 2001)
Acquired NystagmusAcquired Nystagmus
SeeSee--saw nystagmussaw nystagmusPeriodic alternating nystagmusPeriodic alternating nystagmusDownbeat nystagmusDownbeat nystagmusUpbeat nystagmusUpbeat nystagmusGazeGaze--evoked nystagmusevoked nystagmusVestibular (central or peripheral) Vestibular (central or peripheral) nystagmusnystagmusOthers, including acquired Others, including acquired pendularpendular forms forms
VIDEOSVIDEOS
Congenital Nystagmus: Congenital Nystagmus: Related DisordersRelated Disorders
AmblyopiaAmblyopia: poor vision caused by : poor vision caused by abnormal visual development, abnormal visual development, due to abnormal visual due to abnormal visual stimulationstimulationSusceptible ages: birth to 7 or 8 Susceptible ages: birth to 7 or 8 yearsyears
Congenital Nystagmus: Congenital Nystagmus: Related Related Disorders
Strabismus
Congenital Nystagmus: Congenital Nystagmus: Related Related Disorders
Albinism
Congenital Nystagmus: Congenital Nystagmus: Related Related Disorders
Optic Nerve Hypoplasia
Congenital Nystagmus: Congenital Nystagmus: Related Related Disorders
Aniridia
Rods&
Cones
Congenital Nystagmus:
Related Disorders
Retinal Dystrophies
RodCone
Peter’s Anomaly—Congenital Corneal Opacity
Congenital Nystagmus:Related Disorders
Congenital CataractsCongenital Nystagmus:Related Disorders
Latent / Manifest Latent Latent / Manifest Latent Nystagmus: Nystagmus:
Related DisordersRelated Disorders
Any eye condition that affects normal Any eye condition that affects normal development of “fusion,” usually by development of “fusion,” usually by affecting vision in at least one eyeaffecting vision in at least one eyeAmblyopiaAmblyopia: poor vision caused by : poor vision caused by abnormal visual development, due to abnormal visual development, due to abnormal visual stimulationabnormal visual stimulation–– Susceptible ages: birth to 7 or 8 yearsSusceptible ages: birth to 7 or 8 years
Latent / Manifest Latent Latent / Manifest Latent Nystagmus: Nystagmus:
Related Related DisordersStrabismus
Congenital Cataracts
Latent/Manifest Latent Nystagmus:Related Disorders
Déjà vu? Yes, there isconsiderable overlap!
Peter’s Anomaly—Congenital Corneal Opacity
Latent/Manifest Latent Nystagmus:Related Disorders
SpasmusSpasmus NutansNutans: : Related DisordersRelated Disorders
StrabismusStrabismusAmblyopiaAmblyopiaIn In spasmusspasmus nutansnutans--like disease: like disease: brain abnormalitiesbrain abnormalities
DiagnosisDiagnosis
HistoryHistory–– OnsetOnset–– SymptomsSymptoms
LightLight--sensitivitysensitivityDifficulty in darknessDifficulty in darknessOscillopsiaOscillopsia (sensation of the world (sensation of the world shaking or moving)shaking or moving)Dizziness, etc.Dizziness, etc.
Diagnosis (cont.)Diagnosis (cont.)
Eye examEye examEye movement recordingsEye movement recordings–– To verify type of nystagmusTo verify type of nystagmus–– To characterize details, such as To characterize details, such as
convergenceconvergence--damping, null position, damping, null position, etc.etc.
–– To determine best treatment optionsTo determine best treatment options
Eye Movement Recording
Infrared Oculography
Magnetic Search Coil
Congenital Nystagmus:Congenital Nystagmus:WaveformsWaveforms
Latent / Manifest Latent Nystagmus:Waveforms
Spasmus Nutans:Waveform
Diagnosis (cont.)Diagnosis (cont.)
ElectoretinographyElectoretinography (ERG):(ERG): for diagnosis for diagnosis of retinal dystrophies in particular (cone of retinal dystrophies in particular (cone and/or rod dystrophies)and/or rod dystrophies)
Diagnosis (cont.)Diagnosis (cont.)
NeuroimagingNeuroimaging: MRI or CT scan: MRI or CT scan——including:including:–– For acquired nystagmusFor acquired nystagmus–– For any nystagmus with other For any nystagmus with other
associated associated neurologicneurologic abnomalitiesabnomalities
Other testsOther tests
Treatment: Treatment: Optical Correction/AidsOptical Correction/Aids
Glasses, including with tints, prismsGlasses, including with tints, prismsContact lensesContact lensesLow vision aidsLow vision aids
File: /ejf/dlr/ejf/recordings/mitra/11_27_02/BR/BR23.d_OShor
Time
Position
Red: without prismsGreen: with prisms
Effect of Prisms on CN
Treatment:Treatment:SomatosensorySomatosensory StimuliStimuli
Contact lenses, soft or rigid gas permeable Contact lenses, soft or rigid gas permeable Neck / face electrical stimulation or Neck / face electrical stimulation or vibration*vibration*Acupuncture*Acupuncture**Problem: practicality*Problem: practicality(*DISCLAIMER: The presenter does not necessarily promote (*DISCLAIMER: The presenter does not necessarily promote these treatments.)these treatments.)
Treatment:Treatment:MedicationsMedications
Congenital periodic alternating Congenital periodic alternating nystagmus: nystagmus: –– BaclofenBaclofen (not as useful as for (not as useful as for acquired acquired
periodic alternating nystagmus)periodic alternating nystagmus)
PendularPendular nystagmus, in multiple nystagmus, in multiple sclerosis:sclerosis:–– GabapentinGabapentin–– MemantineMemantine
Retrobulbar Space
Botox InjectionTreatment:Medications (cont.)
Treatment:Treatment:Medications (cont.)Medications (cont.)
BotoxBotox injection into orbitinjection into orbitDisadvantages: Disadvantages: –– Possible Possible droopy eyeliddroopy eyelid (“(“ptosisptosis”)”)–– Possible Possible double visiondouble vision–– Wears off in about 8 weeks, Wears off in about 8 weeks,
requiring repeated injectionsrequiring repeated injections
Treatment:Treatment:SurgerySurgery
StrabismusStrabismus correctioncorrection
Treatment:Treatment:SurgerySurgery
Head postureHead posture correction (e.g. correction (e.g. AndersonAnderson--KestenbaumKestenbaum procedure)procedure)
Treatment:Treatment:SurgerySurgery
Improvement of Improvement of visionvision–– Artificial divergence surgeryArtificial divergence surgery–– AndersonAnderson--KestenbaumKestenbaum–– Combined artificial divergence and Combined artificial divergence and
AndersonAnderson--KestenbaumKestenbaum
Eye Muscle SurgerySite of disinsertion
during surgery
Eye Muscle Surgery
Eye Muscle (hooked and sutured)
Suture
Suture
Nose
Forehead
New Research:New Research:Congenital NystagmusCongenital Nystagmus
Underlying causeUnderlying cause——proposed: proposed: –– Lack of normal visual motion during a Lack of normal visual motion during a
critical period of development in critical period of development in infancyinfancy
–– Possible abnormal Possible abnormal proprioceptionproprioception(sensation of position)(sensation of position)
New Research:New Research:Congenital NystagmusCongenital Nystagmus
Diagnosis of waveformsDiagnosis of waveforms is possible in is possible in infancy: 6 months of age or lessinfancy: 6 months of age or lessCorrelation with visionCorrelation with vision
New Research:New Research:Congenital NystagmusCongenital Nystagmus
OscillopsiaOscillopsia (=sensation / perception of (=sensation / perception of world moving / shaking)world moving / shaking)–– A debilitating problem in very few A debilitating problem in very few
congenital nystagmus patientscongenital nystagmus patients–– Associated with Associated with decompensateddecompensated motor or motor or
sensory status (e.g. strabismus, retinal sensory status (e.g. strabismus, retinal dystrophy)dystrophy)
–– May be helped with treatment for the May be helped with treatment for the underlying causeunderlying cause
New Research:New Research:Congenital NystagmusCongenital Nystagmus
Refractive errorsRefractive errors (i.e. astigmatism, far(i.e. astigmatism, far--sightedness, nearsightedness, near--sightedness)sightedness)–– Wider range in CN / albinism Wider range in CN / albinism
patientspatients–– CN / albinism patients with CN / albinism patients with
refractive errors have less tendency refractive errors have less tendency to progress toward “to progress toward “emmetropiaemmetropia” ” (no refractive error)(no refractive error)
New Research:New Research:Congenital NystagmusCongenital Nystagmus
TorsionalTorsional componentcomponent of CNof CN–– Does not significantly affect vision in Does not significantly affect vision in
the null positionthe null position–– Generated centrally (in brain), as Generated centrally (in brain), as
opposed to peripherally (in eye opposed to peripherally (in eye muscles)muscles)
New Research:New Research:Congenital Congenital NystagmusNystagmus
Psychophysical testsPsychophysical tests–– Orientation thresholds:Orientation thresholds:
Lines of different orientations and Lines of different orientations and differing lengths presented for differing differing lengths presented for differing periods of timeperiods of timeCN patients require more time to CN patients require more time to recognize the orientationsrecognize the orientationsCN patients have a harder time with CN patients have a harder time with vertical lines than horizontal linesvertical lines than horizontal lines
Control Patient
Plasma Screen
New New Research:Research:Congenital Congenital NystagmusNystagmus
PsychoPsycho--physical physical teststests
••Latency of Latency of optotypeoptotyperecognitionrecognition
“Static Task:”
500 msec
500 msec
2000 msec
Gaze angles:
5-22o in R or L gaze
At or above visual acuity, CN patients required more time to recognize the “E” than controls
500 msec
2000 msec
“Dynamic Task:”
Stimulus velocities:
10-30o/sec to R or L
At or above visual acuity, CN patients required more time to recognize the “E”than controls
New Research:New Research:Congenital Congenital NystagmusNystagmus
NeuroanatomicNeuroanatomic studystudy of the of the muscle/eye junction (“muscle/eye junction (“enthesisenthesis”)”)–– Differences compared to patients without Differences compared to patients without
nystagmusnystagmus
Enthesial Area
CONTROL HUMAN ENTHESIS
Axon
Myelin
2u
2u
500u
Nerve Ending
Capillary
INS IDIOPATHIC 18 Mos M
Unmylinated Nerve Ending
500u
100u
500u
500u Nerve Endings c Dilated RER
Nerve Endings c Dilated RER
Fragmented Neurolemma
New Research:New Research:Congenital Congenital NystagmusNystagmus
NeuroanatomicNeuroanatomic studystudy of the of the muscle/eye junction (“muscle/eye junction (“enthesisenthesis”)”)–– Suggests a possible role for abnormal Suggests a possible role for abnormal
proprioceptionproprioception (sensation of position) as (sensation of position) as cause of diseasecause of disease
New Research:New Research:Congenital Congenital NystagmusNystagmus
Medication Medication effect:effect:–– One adult CN patient improved with diet pill*One adult CN patient improved with diet pill*–– One child with CN improved with ADHD pill*One child with CN improved with ADHD pill*–– Medications improved vision, strabismus, and Medications improved vision, strabismus, and
depth perception, despite depth perception, despite increased increased nystagmusnystagmusintensityintensity
–– Likely reason: Likely reason: more more foveationsfoveations per secondper second
*These drugs may carry serious side effects and*These drugs may carry serious side effects and have NOT have NOT undergone clinical trial for treatment of undergone clinical trial for treatment of nystagmusnystagmus..
New Research:New Research:Congenital Congenital NystagmusNystagmus
Surgical treatmentsSurgical treatments1. 1. Horizontal Horizontal rectusrectus tenotomytenotomy study in study in
humanshumans (NIH study)(NIH study)–– Improved visual acuity in the childrenImproved visual acuity in the children–– Improved vision subjectively in adultsImproved vision subjectively in adults
(To be published soon(To be published soon——stay tuned…)stay tuned…)
New Research:New Research:Congenital Congenital NystagmusNystagmusSurgical treatmentsSurgical treatments
2.2. LASIKLASIK (laser(laser--assisted in situ assisted in situ keratomileusiskeratomileusis, , refractive surgery)refractive surgery)
–– In 47 In 47 y.oy.o. woman with CN. woman with CNModerate amplitude and frequencyModerate amplitude and frequencyConvergenceConvergence--dampingdampingNo eccentricNo eccentric--gaze nullgaze null
–– After 2 treatments with pupilAfter 2 treatments with pupil--tracking laser tracking laser system:system:
20/40 each eye pre20/40 each eye pre--op with glassesop with glasses20/40 each eye post20/40 each eye post--op without glassesop without glasses
Cornea
Anteriorchamber
Pupil
Iris
Cornea
New Research:New Research:Congenital Congenital NystagmusNystagmus
Surgical Treatment:Surgical Treatment:LASIKLASIK
CorneaCornea
New New Research:Research:Congenital Congenital NystagmusNystagmus
Surgical Surgical Treatment:Treatment:LASIKLASIK
Corneal Flap
Laser appliedto the stroma
Corneal Flap
New Research:New Research:Congenital Congenital NystagmusNystagmus
LASIK for CN (INS) patient??? Only if:LASIK for CN (INS) patient??? Only if:–– ConvergenceConvergence--damping damping nystagmusnystagmus–– No eccentric nullNo eccentric null--pointpoint–– Smaller Smaller nystagmusnystagmus frequencies and frequencies and
amplitudesamplitudes–– Experienced surgeonExperienced surgeon–– Advanced pupilAdvanced pupil--tracking laser systemstracking laser systems–– With full knowledge of the patient about With full knowledge of the patient about
problemsproblems with eccentric ablation zones, with eccentric ablation zones, including monocular including monocular diplopiadiplopia, glare, halos, , glare, halos, and other debilitating symptoms and other debilitating symptoms
New Research:New Research:Acquired Acquired NystagmusNystagmus
Localizing defects in the brainLocalizing defects in the brainOptical treatmentOptical treatment: an electro: an electro--optic optic device, for device, for pendularpendular nystagmusnystagmus, e.g. , e.g. in multiple sclerosisin multiple sclerosisMedicationsMedications, e.g. in multiple sclerosis, , e.g. in multiple sclerosis, periodic alternating periodic alternating nystagmusnystagmus
Thank you for your attention