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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