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Dr Frank FAMOSE

DVM, CES Ophtalmologie

Ekaterinburg May 2010

TONOMETRYTONOGRAPHY

Intra-Ocular Pressure (IOP)

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Hypertension : increase of IOP

Hypotension : Decrease of IOP

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IOP evaluation : manometry

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Direct evaluation of IOP

Principles

DifficultiesUtilisation

PIO evalutation

►Direct : manometry

►Indirect : tonometry

Tension of ocular globe = pressure

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Digital tonometry

EyeEye

FingerFinger

Indentation tonometry

EyeEye

Tonometer’sTonometer’splugplug IndentationIndentation

PressurePressure

Ex : Schi�tz tonometerEx : Schi�tz tonometer

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Aplanation tonometry

EyeEye

PlugPlug

Resistance to Resistance to deformationdeformation

PressurePressure

Ex : Maklakoff, MackayEx : Maklakoff, Mackay--MargMargTonopen, TonovetTonopen, Tonovet

P = f/A

Results and variations

Species Technicalskills

Anesthesia Pupillarydilatation

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Red Eye

Cornealoedema

Mydriasis

Oculartrauma

Lens luxation

Glaucoma

IndicationsIndications

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Practical realisation

►Digital Tonometry

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Practical realisation

►Schiötz tonometry : instrument

Practical realisation

►Schiötz tonometry : animal restraint

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Practical realisation

►Schiötz tonometry : measurements

Practical realisation

►Schiötz tonometry : how to get good results?

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Variation factors

Restraint Cornea Globe movements

Calibration Cleaning

Practical realisation

►Tonopen : instrument

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Practical realisation

►Tonopen : animal restraint

Practical realisation

►Tonopen : measurements

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Variation factors

Restraint Calibration Normal values

Measurequality

Instrument management

Practical realisation

►Tonovet : instrument

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Practical realisation

►Tonovet : animal restraint

How to choose your tonometer ?

Quality ?

Scheduleduse ?

Financial outcomes ?Simplicity ?

Indirect costing ?

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Quality ?

Tonopen/Tonovet

Schi�tz Tonometer

Digital tonometry

Just an example…

Overweights Tonopen SchiotzPrice 2500 250

Direct cost/use 10 1

Other costs 0.5 0.5

Nurse cost 0.6 3

Vet cost 0.8 4

Total cost 11.9 8.5If double use 6.9 8.0

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Principle

Calculationof « C »

Examination

ProtocolIndications

Practical use

Tonography

Conclusion

Essential evaluation

Equipement necessary

Easy to use