headtiltsetc_2copy - The Private Eye Clinic

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Transcript headtiltsetc_2copy - The Private Eye Clinic

Working out head tilts &
face turns
LIONEL KOWAL
RANZCO SQUINT CLUB
Dunedin 2005
Q1: Is HT driven by
visual activity?
Instruction to patient:
Close your eyes and hold your head
straight.

Uncertain: pt closes eyes, Dr tilts head
randomly, pt asked to straighten head
Both eyes closed HT persists
Eyes closed

HT not related to visual
activity!

Causes: Vestibular problem /
ocular tilt reaction / tectal
pathology/ neck problems
BE closed - HT goes
 HT

driven by visual activity
Now determine: Is HT driven by
– Right eye fixing
RF
– Left eye fixing
LF
– Either eye fixing
EE
– Only when both eyes are fixing BE
Either eye drives HT
 Congenital
nystagmus with
oblique null

Look for other features of CN to confirm

De Decker or Sousa Dias for treatment guidelines
Special case:
Head tilt to fixing eye
 LF
2
drives HT to L
causes:
 1. Torsional null for LMLN
 2. L Orbital reasons
LF drives HT to L
1. Torsional LMLN

Seen in cong ET

Can see fine torsional N on slit
lamp

N degrades vision - vision
improves when N blocked
LF drives HT to L
1. Torsional LMLN

Preference for fixation in intorsion HT to fixing eye recruits SO which
acts as a ‘brake’ for [& is a null for]
torsional component of the LMLN

Usually the dominant eye but can be the
‘wrong’ eye
Special case:
Alternating Head Tilt
 LF
drives L tilt
 RF drives R tilt
=
Ciancia’s syndrome
Ciancia’s syndrome

Head tilt / face turn recruits a muscle to
block the torsional / horizontal component
of LMLN  improves vision
 T: HT to fixing eye - recruits Sup Obl to
‘brake’ T LMLN
 H: FT to fixing eye - recruits Medial Rectus
to ‘brake’ H LMLN
LF drives HT  L
2. Orbital reason

Orbital scarring
 Restrictive strabismus esp Graves’

Motor reasons
 Sensory reasons - acquired
astigmatism from tight muscles
HT driven by binocularity

RF = LF = no HT

Strabismus the cause

Tilt R and do a cover test to
discover the cause!
RF  Head Tilt to L
Problem with R orbit
Face Turn - L

Approach the same way as tilt - a few
differences
 Is the FT visually driven: “Close your eyes
and hold your head straight”
 If it’s visually driven, is it driven by:
 LF
RF
EE
BE ?
Face Turn - Left





If driven by:
LF : Fixation- in- adduction for horizontal LMLN
or L orbital problem
RF : R orbital problem
EE : cong nystagmus
BE : strabismus
Alternating Face Turn
2 causes
1. Ciancia’s syndrome

LF : L FT
 RF : R FT

Ciancia’s syndrome: preference for
fixation in adduction because
[probably] recruiting medial rectus
‘brakes’ horizontal component of
LMLN  improved vision
Alternating Face Turn
2. Periodic alternating nystagmus
‘Regular’ CN with 2 null zones
 Much more frequent than
suspected esp albinism
 CAREFUL FAT SCAN : ANY
photos showing FT  R suggest
PAN

Alternating Face Turn
2. Periodic alternating nystagmus

Usually asymmetric periodicity =
‘aperiodic’ say, 90% FT  L, 10% FT
R
 Prolonged in- office exam
Astigmatism
 Wrong
cyl axis can  head tilt
 Uncorrected
astigmatism : pt uses
corner of palpebral fissure to act as
‘pinhole’
Working out head tilts &
face turns
THANK
YOU