30. Ewald’s Law
• 1st: The axis of
nystgmus parallels the
anatomic axis of the SCC that
generated it.
• 2nd: Ampullopetal flow
produces a stronger response
than ampullofugal flow in
the horizontal canal.
• 3rd: Ampullofugal flow
produces a stronger response
than ampullpetal flow in
the anterior and posterior
canals.
41. Methods seldom used:
(Semont maneuver for PC-BPPV
barbecue maneuver for HC-Can
Gufoni maneuver for both HC-Can & Cup-C of HC-Cup)
42. Intractable HC-BPPV?
• Always HC-Cup=> Rapid head rotation
• Methods for deciding the lesion side:
bow and lean nystagmus
lying-down nystagmus
head pitch down nystagmus
pseudospontaneous nystagmus
null point
• Intractable HC-Can? => concept of light
cupula
43. A single therapy for all subtypes of horizontal canal positional vertigo.
Laryngoscope. 2005 Aug;115(8):1432-5 Chiou WY, Lee HL, Tsai SC, Yu TH, Lee XX.
Radpid head rotation for HC-Cup(97年醫學會)
44. Intractable HC-BPPV?
• Always HC-Cup=> Rapid head rotation
• Methods for deciding the lesion side:
bow and lean nystagmus
lying-down nystagmus
head pitch down nystagmus
pseudospontaneous nystagmus
null point
• Intractable HC-Can? => concept of light
cupula
46. 口訣: HC-Can躺向健側 HC-Cup仆向健側
lying down nyst. head pitch nyst.
http://bmcophthalmol.biomedcentral.com/articles/10.1186/1471-2415-14-136
47. Intractable HC-BPPV?
• Always HC-Cup=> Rapid head rotation
• Methods for deciding the lesion side:
bow and lean nystagmus
lying-down nystagmus
head pitch down nystagmus
pseudospontaneous nystagmus
null point
• Intractable HC-Can? => concept of light
cupula
70. Take home message
• Epley maneuver for PC-BPPV
FPP for HC-BPPV
Deep head hanging position for AC-BPPV
• Intractable PC-BPPV may be due to
misdiagnosis
malpractice of CRP(Canalith Repositioning Procedure)
• Intractable HC-BPPV always found in HC-Cup
rapid head rotation for HC-Cup
tools to decide lesion side
concept of light cupula
94. The ear doctor smiled reassuringly and spoke the lie for which
doctors should be immediately jailed… ‘Relax, Stevie, this won’t
hurt.’ I believed him.“