title: Identification of predictors and development of a screening protocol for cerebello-pontine lesions in patients presenting with audio-vestibular dysfunction.
abstract: OBJECTIVE
  Magnetic resonance imaging (MRI) scanning in the investigation of cerebellopontine angle lesions represents a finite resource, the use of which needs to be carefully rationalised. Our aim was to identify predictive factors that can distinguish between patients with and without cerebellopontine angle lesions, and develop a screening protocol which could be useful in the clinical setting as an aid to clinical judgment.
  
  
  METHODS
  Case-control study.
  
  
  METHODS
  Secondary care.
  
  
  METHODS
  Audio-vestibular features were collated on 136 patients (M : F 1.39 : 1) and 288 controls (M : F 1 : 1.1).
  
  
  METHODS
  Diagnostic by analysis of symptoms and audiometric data using logistic regression, receiver-operator characteristic curves and backwards elimination.
  
  
  METHODS
  Development of a predictive algorithm comprising those factors which are most strongly predictive of the presence of a cerebellopontine angle lesion.
  
  
  RESULTS
  Positive predictors of a cerebellopontine angle lesion include the interaural threshold difference at 1 (P = 0.044) and 4 kHz (P = 0.034). The threshold in the better hearing ear at 0.25 kHz exerts a negative predictive (i.e. protective) effect (P = 0.005). The presence of tinnitus does not appear to influence the outcome on logistic regression. Although vertigo does exert an influence on the overall model, its impact is highly equivocal.
  
  
  CONCLUSIONS
  We have identified audiometric factors which exert a positive and negative predictive influence on the presence of a cerebellopontine angle lesion, and audiovestibular symptoms which appear to exert little effect on the model. Our predictive equation represents a user-friendly standardised method of risk-stratification of patients within a general otolaryngology clinic.
authors.affiliation: Department of Otolaryngology, Charing Cross Hospital, London, UK. paul.chatrath@royalfree.nhs.uk
authors.forename: P
authors.initials: P
authors.lastname: Chatrath
authors.forename: A
authors.initials: A
authors.lastname: Frosh
authors.forename: A
authors.initials: A
authors.lastname: Gore
authors.forename: R
authors.initials: R
authors.lastname: Nouraei
authors.forename: J
authors.initials: J
authors.lastname: Harcourt
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold / Q000502:physiology; D016022:Case-Control Studies; D002531:Cerebellum / Q000473:pathology*; D015897:Comorbidity; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000453:epidemiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D011149:Pons / Q000473:pathology*; D011237:Predictive Value of Tests; D015995:Prevalence; D011446:Prospective Studies; D012372:ROC Curve; D012720:Severity of Illness Index; D014012:Tinnitus / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology; D014717:Vertigo / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology; D014722:Vestibule, Labyrinth / Q000473:pathology* / Q000503:physiopathology*