title: Apogeotropic variant of lateral semicircular canal benign paroxysmal positional vertigo: is there a correlation between clinical findings, underlying pathophysiologic mechanisms and the effectiveness of repositioning maneuvers?
abstract: OBJECTIVE
  The apogeotropic variant of horizontal semicircular canal (h-SCC) benign paroxysmal positional vertigo (BPPV) is attributed to canalithiasis of the anterior arm or cupulolithiasis. This study is an attempt to distinguish the most effective maneuvers for each case, by investigating any correlation, between the clinical findings or the treatment options and the possible location of the displaced debris.
  
  
  METHODS
  A review of the literature (1990-2012) was conducted via the PubMed database with the search terms "apogeotropic nystagmus and benign paroxysmal positional vertigo."
  
  
  METHODS
  Articles on central nervous system lesions were excluded.
  
  
  METHODS
  The studies included in the analysis provided detailed diagnostic and therapeutic protocols, supported by the resolution of the signs and symptoms through repositioning maneuvers.
  
  
  RESULTS
  Descriptive statistics were used to summarize the findings. Intergroup and intragroup comparisons were performed through Pearson's χ or Fischer's exact test.
  
  
  CONCLUSIONS
  Protocols vary considerably among studies. Nystagmus from seated to supine position is the best studied secondary clinical sign and possibly a clinical indication of cupulolithiasis. In patients with symmetrical responses in the head yaw test, no significant differences can be detected in the occurrence of secondary signs of lateralization compared to patients with asymmetrical responses. The Gufoni maneuver seems to be effective in all pathophysiologic types of apogeotropic h-SCC BPPV. The Barbeque and Vannucchi-Asprella maneuvers mainly target at lithiasis of the anterior ampullary arm. The results of this analysis may imply that different clinical subgroups of h-SCC BPPV may regard to different pathophysiologic and therapeutical mechanisms.
authors.affiliation: ENT Clinic, Democritus University of Thrace, Alexandroupolis, Greece. mariariga@hotmail.com
authors.forename: Maria
authors.initials: M
authors.lastname: Riga
authors.forename: Stavros
authors.initials: S
authors.lastname: Korres
authors.forename: George
authors.initials: G
authors.lastname: Korres
authors.forename: Vasilios
authors.initials: V
authors.lastname: Danielides
mesh_terms: D065635:Benign Paroxysmal Positional Vertigo; D006801:Humans; D020347:Lithiasis / Q000150:complications / Q000473:pathology; D009760:Nystagmus, Physiologic / Q000502:physiology; D013506:Otologic Surgical Procedures; D011187:Posture / Q000502:physiology; D012665:Semicircular Canals / Q000503:physiopathology*; D016896:Treatment Outcome; D014717:Vertigo / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*