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Glaucoma is a disease associated with changes in structure to the optic nerve and retinal nerve fiber layer.  Functional vision is also affected as damage occurs.  Vision loss occurs after the damage has been apparent. Both optic nerve evaluation and perimetry are needed in order to diagnose glaucoma and to monitor the growth of the disease.   Visual field testing depends on the patient participating instead of a procedure that is performed by a technician. Patient performance may vary from test to test which may lead to defects changing in appearance due to poor performance and not actually the disease worsening.  Some studies suggest that it may take up to three tests before a patient becomes familiar with performing the visual field test.  Operator issues can also be important.  Instruction, supervision and coaching are all needed to help obtain a valid test result.  Guided Progression Analysis software program was developed to aid the clinician in differentiating true changes from random variability.  GPA determines the statistical significance of any observed changes using a database. The two forms of GPA- even and trend analysis compliment each other.  The event analysis will show which test points have changed by more than amounts expected due to typical testing variability.  The trend analysis uses all available data to quantify the rate of change, and therefore helps doctor’s assess the clinic importance of observed changes.       

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Vision Treatments & Technology

This journal will include information in the optometry and ophthamology fields including studies and other valuable eye care stories.

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