Tonopen applanation tonometer with small tip, ultrasound

verifies applanation.

Freshly enucleated goat’s eyes

Pressure checked on deep sclerectomy

drawbacks1. Dead eye with inactive

metabolism2. Test performed with eye out of

socket.3. Deep sclerectomy depth was not

uniform in all eyes .

Instrument takes many measurements and averages them.

Showing how pressure was changed

When vitreous pressure was increased anterior chamber (ac)pressure did not increase or it even dropped. But when ac

pressure was increased, vitreous pressure went up hand in hand.

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conclusions1. Anterior chamber (AC) pressure as is measured clinically today

does not corelate with vitreous pressure.AC pressure values may be low or normalbut vitreous pressure may be very high.

2. Glaucoma damage happens because of pressure effects on the nerve head, namely the vitreous pressure.

3. The findings agree with a previous french study in its findings, though pressure measurement method in the french study was different.( acta ophthalmologica , Hernandez and Bolivar2010)

4. This may explain pathogenesis of low pressure glaucoma.5. Instruments to measure vitreous pressure are

required.Surgeries /implants/drugs designed to lower anterior chamber pressure may not help a patient.