The Frankfort Line Audit

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The Frankfort Line Audit

• Mr S Ahluwalia, Mr V Veer, Mr GS Kenyon
• Whipps Cross University Hospital, London
• British Rhinological Society Meeting
• Liverpool, 23rd May 2008

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The Frankfort Line

• A craniometric horizontal plane determined by the
  inferior borders of the bony orbits and the upper
  margin of the auditory meatus

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Background

• Frankfort line first introduced at an
  anthropological conference in Frankfurt, Germany
  1884
• Originally used as a craniometric reference plane
  for classification purposes

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The Frankfort Line

• Essential for planning of Septorhinoplasty
  surgery
• Assessment of the nasal tip

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National Guidelines

• IMI May 2006
• 9 views
• AP
• lateral x 2
• 45 oblique x 2
• Inferior, worms eye views x 2
• Superior, birds eye views x 2

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Standard Views
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Standard Views
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Problems
9
Problems
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Method

• Group A
• 100 patients pre operative photographs
• Assessed for deviance from the Frankfort plane

• Group B
• 100 patients assessed post intervention
• Statistical analysis

• Intervention - IMI national guidelines
  introduced

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Results
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Results
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Results
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Statistics

• Data analysis - Parametric data
• Unpaired t-test used
• SPSS used for calculations
• Results validated by statistician

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Results

• Group A
• Mean 2.83
• SD 6.40
• SEM 0.62

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Results

• Group B
• Mean 0.98
• SD 4.65
• SEM 0.47

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Results

• Difference between means 1.85
• 95 confidence interval of difference between the
  means 0.31-3.39
• t 2.3624
• p0.0191 therefore statistically significant

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Conclusion

• Introduction of national guidelines significantly
  reduces error of images obtained
• Enhances accuracy of pre-operative planning
  process
• Improves post-operative litigation protection

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Further work

• Currently underway
• What is the acceptable error in deviation from
  the Frankfort Plane, before tip surgery is
  contemplated?

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• Any questions?