Presentation is loading. Please wait.

Presentation is loading. Please wait.

STRABISMUS: IS IT ‘STRABISMIC’ ? …. NEUROLOGICAL? OR BOTH? LIONEL KOWAL DIRECTOR, OCULAR MOTILITY CLINIC, RVEEH SENIOR CLINICAL FELLOW, DEPT OPHTHALMOLOGY,

Similar presentations


Presentation on theme: "STRABISMUS: IS IT ‘STRABISMIC’ ? …. NEUROLOGICAL? OR BOTH? LIONEL KOWAL DIRECTOR, OCULAR MOTILITY CLINIC, RVEEH SENIOR CLINICAL FELLOW, DEPT OPHTHALMOLOGY,"— Presentation transcript:

1

2 STRABISMUS: IS IT ‘STRABISMIC’ ? …. NEUROLOGICAL? OR BOTH? LIONEL KOWAL DIRECTOR, OCULAR MOTILITY CLINIC, RVEEH SENIOR CLINICAL FELLOW, DEPT OPHTHALMOLOGY, UNIVERSITY OF MELBOURNE FIRST VICE PRESIDENT, INTERNATIONAL STRABISMOLOGICAL ASSOCIATION, LIONEL KOWAL DIRECTOR, OCULAR MOTILITY CLINIC, RVEEH SENIOR CLINICAL FELLOW, DEPT OPHTHALMOLOGY, UNIVERSITY OF MELBOURNE FIRST VICE PRESIDENT, INTERNATIONAL STRABISMOLOGICAL ASSOCIATION,

3 OVERVIEW….  OF THE CAUSES, ASSOCIATIONS AND TYPES OF STRABISMUS  IDENTIFYING SOME COMMON / UNDER- RECOGNISED ASSOCIATIONS  OF THE CAUSES, ASSOCIATIONS AND TYPES OF STRABISMUS  IDENTIFYING SOME COMMON / UNDER- RECOGNISED ASSOCIATIONS

4 STRABISMUS  Any ocular misalignment INCLUDES:  Abnormalities of development of acuity  Abnormalities of development of binocularity  The variants of congenital nystagmus  Any ocular misalignment INCLUDES:  Abnormalities of development of acuity  Abnormalities of development of binocularity  The variants of congenital nystagmus

5 CHILDHOOD STRABISMUS  1. Derive largely from refractive disorders  2. Pure neurological  3. Derive largely from abnormal early visual devpt  4. Special types  1. Derive largely from refractive disorders  2. Pure neurological  3. Derive largely from abnormal early visual devpt  4. Special types

6 STRABISMUS: END RESULT OF A COMPLEX JIGSAW PUZZLE Abnormalities in one / more of…  Sensory development  Refraction  Orbital anatomy  EOM anatomy / physiology  Cortical / supranuclear  Accommodation / convergence either cause or are caused by strabismus Abnormalities in one / more of…  Sensory development  Refraction  Orbital anatomy  EOM anatomy / physiology  Cortical / supranuclear  Accommodation / convergence either cause or are caused by strabismus

7 COMPLEX JIGSAW PUZZLE Abnormal Sensory development  Amblyopia  Suppression  Abnormal retinal correspondence  Amblyopia  Suppression  Abnormal retinal correspondence

8 COMPLEX JIGSAW PUZZLE Abnormal Refraction  Hyperopia or ‘plus’ error * Causes esotropia  Any asymmetric refractive error Causes amblyopia, esotropia if + *so-called ‘long sighted’ - NOT the mirror image of short sighted. The patient can see clearly by generating focusing effort = accommodation  Hyperopia or ‘plus’ error * Causes esotropia  Any asymmetric refractive error Causes amblyopia, esotropia if + *so-called ‘long sighted’ - NOT the mirror image of short sighted. The patient can see clearly by generating focusing effort = accommodation

9 COMPLEX JIGSAW PUZZLE Abnormal orbital anatomy1  Orbital pulley heterotopy Changes muscle actions  Globe size distorting muscle cone Causes pseudo- 6th  Shallow / deep orbit Shallow: more prone to exotropia  Orbital pulley heterotopy Changes muscle actions  Globe size distorting muscle cone Causes pseudo- 6th  Shallow / deep orbit Shallow: more prone to exotropia

10 COMPLEX JIGSAW PUZZLE Abnormal orbital anatomy 2  Intorted / extorted orbit More prone to alphabet patterns  Plagiocephaly More prone to oblique dysfunction  Intorted / extorted orbit More prone to alphabet patterns  Plagiocephaly More prone to oblique dysfunction

11 COMPLEX JIGSAW PUZZLE Abnormal EOM anatomy / physiology  Oblique muscle dysfunction Abnormal elevation / depression in AB- or AD- duction Globe torsion  Abnormal innervation [Duane's, CFEOM] Strange incomitant strabismus  Oblique muscle dysfunction Abnormal elevation / depression in AB- or AD- duction Globe torsion  Abnormal innervation [Duane's, CFEOM] Strange incomitant strabismus

12 COMPLEX JIGSAW PUZZLE Abnormal cortical / supranuclear substrate 1   motor fusion oculomotor ‘shock absorber’ / ‘glue’ that tries to keep eyes straight   sensory fusion stereopsis  Abnormal binocular columns   motor fusion oculomotor ‘shock absorber’ / ‘glue’ that tries to keep eyes straight   sensory fusion stereopsis  Abnormal binocular columns

13 COMPLEX JIGSAW PUZZLE Abnormal cortical / supranuclear substrate 2  Abnormal interneurons  Latent Manifest Latent Nystagmus = LMLN = Fixation Maldevelopment N  Just about any cause / association of devptl delay  Chiari  PVL  Abnormal interneurons  Latent Manifest Latent Nystagmus = LMLN = Fixation Maldevelopment N  Just about any cause / association of devptl delay  Chiari  PVL

14 COMPLEX JIGSAW PUZZLE Abnormal Accom - Conv relationship  Accom  too much convergence  Conv  too much accommodation *too little is rarely a problem  Accom  too much convergence  Conv  too much accommodation *too little is rarely a problem

15 TYPES OF STRABISMUS  1. Derives from refractive disorders  2. Pure neurological  3. Derives from abn early visual devpt  4. Special types  1. Derives from refractive disorders  2. Pure neurological  3. Derives from abn early visual devpt  4. Special types

16 NORMAL ACCOMMODATION Accommodation and convergence = Focus and Aim = Focus and Aim are very tightly linked

17 ACCOMMODATIVE / ‘OPTOMETRIC’ ESOTROPIA  +4 : Abn degree of accommodation required to see clearly  Abn amount of accomm convergence is generated  competes against motor fusion [oculomotor shock absorber]  +4 : Abn degree of accommodation required to see clearly  Abn amount of accomm convergence is generated  competes against motor fusion [oculomotor shock absorber]

18 WHAT DOES +4 MEAN?  For distance, generates same accommodation that ‘perfect’ person generates when looking 1/4 m away.  For distance fixation, eyes will tend to a point 25cm away  When an object 25cm away, eyes will a point 12 cm away  For distance, generates same accommodation that ‘perfect’ person generates when looking 1/4 m away.  For distance fixation, eyes will tend to a point 25cm away  When an object 25cm away, eyes will a point 12 cm away

19 ACCOMMODATIVE / ‘OPTOMETRIC’ ESOTROPIA  Exactly the same can happen with low + and abnormal accomm - convergence relationship*  Many of these  bifocals *many synonyms - convergence Xs, high AC/A ratio  Exactly the same can happen with low + and abnormal accomm - convergence relationship*  Many of these  bifocals *many synonyms - convergence Xs, high AC/A ratio

20 Developing an esotropia…  Prolonged accommodation  tendency to inappropriate convergence and increased tone in medial recti  Increased tone will eventually exceed motor fusional reserve and  esotropia!  Initially reversible with glasses  Eventually the medial rectus shortens so much that only botox or surgery will work  Glasses still required to prevent recurrence [and, when older, for clear vision]  Prolonged accommodation  tendency to inappropriate convergence and increased tone in medial recti  Increased tone will eventually exceed motor fusional reserve and  esotropia!  Initially reversible with glasses  Eventually the medial rectus shortens so much that only botox or surgery will work  Glasses still required to prevent recurrence [and, when older, for clear vision]

21 Accommodative esotropia  Usually 2-5 yrs old  Usually high + [thick magnifying lenses]  Sometimes low / normal + with abnormal relation b/w accomm and convergence  Background of normal visual devpt in first 6mo of life  Usually 2-5 yrs old  Usually high + [thick magnifying lenses]  Sometimes low / normal + with abnormal relation b/w accomm and convergence  Background of normal visual devpt in first 6mo of life

22 Developing an esotropia… Happens more readily * if motor fusion is impaired:  chromosomal defect / devptl delay  Amblyopia  Orbital anomaly  LMLN * younger, lower + Happens more readily * if motor fusion is impaired:  chromosomal defect / devptl delay  Amblyopia  Orbital anomaly  LMLN * younger, lower +

23 ‘Breakdown of pre- existing phoria…’ Only acceptable as a presumptive label if:  Wears thick magnifying lenses  ± amblyopia  Accomm disturbed e.g. Ditropan Only acceptable as a presumptive label if:  Wears thick magnifying lenses  ± amblyopia  Accomm disturbed e.g. Ditropan

24 TYPES OF STRABISMUS  1. Derives from refractive disorders  2. Pure neurological  3. Derives from abn early visual devpt  4. Special types  1. Derives from refractive disorders  2. Pure neurological  3. Derives from abn early visual devpt  4. Special types

25 ‘ Pure ’ neurological strabismus  True cong sup obl palsy  6th  CFEOM [hypoplasia sup div 3rd; KIF mutation]..have 2ary effects that are dependent on age of onset and associated factors such as refraction  True cong sup obl palsy  6th  CFEOM [hypoplasia sup div 3rd; KIF mutation]..have 2ary effects that are dependent on age of onset and associated factors such as refraction

26 R SOP HEAD TILT TO LEFT

27 R IO OA R SO UA TIGHT RSR RIR ‘UA’

28 True sup obl palsy LSO OK RSO ?absent

29 REAL CONG R SOP & CONG ET FIXING WITH PARETIC R EYE

30 R SO atrophic

31 Fake SOP Conditions that simulate SOP False +ve diagnostic rate ?50%  Abnormal cyclovertical anatomy  Craniofacial anomalies  Posteroplaced trochlea [Bagolini]  Fink : 20% of SO and IO have > 30 degrees asymmetry in course  Demer: orbital pulley displacements  Abnormal physiology  Brodsky’s wild pitch  Abnormal cyclovertical anatomy  Craniofacial anomalies  Posteroplaced trochlea [Bagolini]  Fink : 20% of SO and IO have > 30 degrees asymmetry in course  Demer: orbital pulley displacements  Abnormal physiology  Brodsky’s wild pitch

32 TYPES OF STRABISMUS  1. Derives from refractive disorders  2. Pure neurological  3. Derives from abnormal early visual development  4. Special types  1. Derives from refractive disorders  2. Pure neurological  3. Derives from abnormal early visual development  4. Special types

33 1. Abnormal symmetric acuity devpt  ‘Congenital Nystagmus’ * = CN  Bilateral bad refractive error  Albinism : optic n dysplasia, foveal hypoplasia  Bil optic n hypoplasia  Bil cataracts  CN degrades vision further * aka Idiopathic Infantile N, Cong motor N, Cong Sensory N,…  Bilateral bad refractive error  Albinism : optic n dysplasia, foveal hypoplasia  Bil optic n hypoplasia  Bil cataracts  CN degrades vision further * aka Idiopathic Infantile N, Cong motor N, Cong Sensory N,…

34 ‘Congenital Nystagmus’ = CN  Pendular / jerk  Greater on lateral gaze  UNIQUE : CONVERGENCE NULL  Face turns  Pathognomonic waveform  Pendular / jerk  Greater on lateral gaze  UNIQUE : CONVERGENCE NULL  Face turns  Pathognomonic waveform

35 CN: face turn null & convergence null Null zone on R gaze drives face turn / tilt to L N to L when L of null N to R when R of null

36 Convergence null : unique to CN

37 Abnormal binocularity devpt  Latent Manifest Latent N * Caused by…  Any strabismus  Asymmetric refraction  Monocular vision reducing pathology - cataract, optic n hypo,…. * aka Fixation Maldevelopment N Caused by…  Any strabismus  Asymmetric refraction  Monocular vision reducing pathology - cataract, optic n hypo,…. * aka Fixation Maldevelopment N

38 Abnormal binocularity devpt  Latent Manifest Latent N  Jerk  Greater on ABduction  UNIQUE : Fast phase to fixing eye  Face turns : RF  R face turn, LF  L face turn  Head tilts : RF  R tilt, LF  L tilt  Jerk  Greater on ABduction  UNIQUE : Fast phase to fixing eye  Face turns : RF  R face turn, LF  L face turn  Head tilts : RF  R tilt, LF  L tilt

39 LMLN  VIDEO OF POST OP LMLN; NOW ‘PURE’ LN Esophoria after Exotropia surgery N to fixing eye

40 LMLN : N  fixing eye Fast phase to fixing eye

41 LMLN  COMMONLY  CONGENITAL ESOTROPIA but can cause / be associated with other strabismus  Also CAUSES DISSOCIATED H & V DEVIATIONS  COMMONLY  CONGENITAL ESOTROPIA but can cause / be associated with other strabismus  Also CAUSES DISSOCIATED H & V DEVIATIONS

42 CONGENITAL ESOTROPIA

43 ASSOCIATIONS OF LMLN & Congenital ET  Down’s 30%  Severe neonatal course IVH /HC near 100%  PVL  Down’s 30%  Severe neonatal course IVH /HC near 100%  PVL

44 VERTICALS IN CONG STRAB : DVD Dissociated Vertical Deviation  Common pattern:  Right fixation: L  L fixation: R  Contralateral DVD is the end result of ‘braking’ the torsional component of LMLN in the fixing eye to try and improve acuity  Common pattern:  Right fixation: L  L fixation: R  Contralateral DVD is the end result of ‘braking’ the torsional component of LMLN in the fixing eye to try and improve acuity

45 VERTICALS IN CET : DVD RE fixing LE 

46

47 CONGENITAL STRABISMUS  Head turns / face tilts are common  Caused by attempts to minimise blur effect of the LMLN  Head turns / face tilts are common  Caused by attempts to minimise blur effect of the LMLN

48 Alternating Face Turn  L Fixation : L Face Turn  R Fixation : R Face Turn  Ciancia’s syndrome: preference for fixation in adduction because recruiting medial rectus ‘brakes’ horizontal component of LMLN  improved vision  L Fixation : L Face Turn  R Fixation : R Face Turn  Ciancia’s syndrome: preference for fixation in adduction because recruiting medial rectus ‘brakes’ horizontal component of LMLN  improved vision

49 Special case: Head tilt to fixing eye  LF drives HT to L  RF : no HT Caused by Torsional LMLN  LF drives HT to L  RF : no HT Caused by Torsional LMLN

50 LF drives HT to L Torsional LMLN  LMLN is the cong nystag seen with disorders of binocular development  [?always] Seen in cong ET = Fixation Maldevelopment N. Usually has H component, sometimes T as well  Fine torsional N on slit lamp  N degrades vision - vision improves when N blocked  LMLN is the cong nystag seen with disorders of binocular development  [?always] Seen in cong ET = Fixation Maldevelopment N. Usually has H component, sometimes T as well  Fine torsional N on slit lamp  N degrades vision - vision improves when N blocked

51 Special case: Alternating Head Tilt  LF drives L tilt  RF drives R tilt = Ciancia’s syndrome  LF drives L tilt  RF drives R tilt = Ciancia’s syndrome

52 Recap… Abnormal binocularity devpt  Latent Manifest Latent N  Features of this type of strab recognised by the accompaniments.  LMLN, + one/ more of…  Head tilt / face turn to fixing eye  DVDs  Large angle esotropia  Features of this type of strab recognised by the accompaniments.  LMLN, + one/ more of…  Head tilt / face turn to fixing eye  DVDs  Large angle esotropia

53 ‘Ophthalmic’ PVL  Optic n hypoplasia uni-/bi-  Cognitive visual problems - normal acuity  Reduced acuity  LMLN  CN  Optic n hypoplasia uni-/bi-  Cognitive visual problems - normal acuity  Reduced acuity  LMLN  CN

54 THINGS THAT LOOK LIKE ‘ STRABISMIC ’ STRABISMUS  CHIARI – later onset  ‘ deterioration of old latent strabismus ‘ – there always has to be a credible background / predisposition. And a reason for breakdown  CHIARI – later onset  ‘ deterioration of old latent strabismus ‘ – there always has to be a credible background / predisposition. And a reason for breakdown

55 THINGS THAT LOOK LIKE ‘ STRABISMIC ’ STRABISMUS  Autoimmune neuropathies  Myesthenia  Autoimmune neuropathies  Myesthenia

56 Strabismus syndromes  Duane’s  Brown’s  Duane’s  Brown’s

57 Brown’s Tight superior oblique tendon Restricted elevation in aDuction

58 Duane’s Retraction on adduction Retraction R on L gaze Restricted aDduction R Restricted aBduction L Co-firing Lateral rectus on aDuction

59 Duane’s Retraction L on R gaze Restricted aDduction L Co-firing lateral rectus on aDuction

60 THANK YOU


Download ppt "STRABISMUS: IS IT ‘STRABISMIC’ ? …. NEUROLOGICAL? OR BOTH? LIONEL KOWAL DIRECTOR, OCULAR MOTILITY CLINIC, RVEEH SENIOR CLINICAL FELLOW, DEPT OPHTHALMOLOGY,"

Similar presentations


Ads by Google