1/31/2018. Course Objectives. Diagnostic Testing. Optic Nerve Damage ANATOMY AND PHYSIOLOGY OF A GLAUCOMA WORK-UP/TONOMETRY TECHNICIAN: -SDP

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ANATOMY AND PHYSIOLOGY OF A GLAUCOMA WORK-UP/TONOMETRY KNOW THE DISEASE PROCESS TECHNICIAN: EXPLAIN PROCESS OF EXAMINATION Presenters: Dana McMahan, COA Nicole Smith, COA Engage with patient s, help

1 ANATOMY AND PHYSIOLOGY OF A GLAUCOMA WORK-UP/TONOMETRY KNOW THE DISEASE PROCESS TECHNICIAN: EXPLAIN PROCESS OF EXAMINATION Presenters: Dana McMahan, COA Nicole Smith, COA Engage with patient s, help alleviate their anxiety 1) Course Objectives Introduction to Glaucoma Glaucoma- An eye disease that damages the eye s optic nerve when the buildup of Aqueous Humor in the Anterior Chamber is too much. With the eye s drainage system not working properly in controlling the out flow of aqueous humor, the excessive fluid buildup increases the eye pressure (IOP), and can therefore damage the optic nerve 2) Diagnostic testing and questions pertaining to the glaucoma patient 3) Introduction to Tonometry Optic Nerve Damage Diagnostic Testing Damage is permanent Peripheral vision affected Diagnosed by: Goal: -Frequent diagnostic testing -Preserve vision -Frequent IOP checks -Prevent further vision loss -Visual Fields -OCT -SDP -Pachymetry 1

Diagnostic Testing HVF- Humphry Visual Field OCT- RNFL Optical Coherence Tomography (Retinal Nerve Fiber Layer) Light waves Evaluates the patient s peripheral vision 1 eye at a time Color imaging

testing Stereo Disc Photos Pachymetry-Pach Optic nerve head (Size, Shape, Health of Rim) Accuracy significantly greater Better detection of disc hemorrhages Cup to Disc Ratio (C.D.) Corneal thickness High IOP s vs.

99 Glaucoma Current & Past Medical History Personal Hx- General history of previous Tx Family Hx Currently on Tx, (tried drops that did not work, allergy to any drops, any Sx/Tx) Highest eye

injury or blunt force trauma to eye, causing the eye pressure to increase causing optic nerve damage Lack of blood flow can be associated with optic nerve damage.

Poor blood circulation can be linked to optic nerve damage for African American patients ask if they have a Hx of Sickle Cell Anemia.

2 Diagnostic Testing HVF- Humphry Visual Field OCT- RNFL Optical Coherence Tomography (Retinal Nerve Fiber Layer) Light waves Evaluates the patient s peripheral vision 1 eye at a time Color imaging Age-range findings Shows blind spots, allows the MD to determine if there is indeed Glaucoma damage and how extensive that damage is Health/Thinning of Optic Nerve Used in conjunction with other testing Stereo Disc Photos Pachymetry-Pach Optic nerve head (Size, Shape, Health of Rim) Accuracy significantly greater Better detection of disc hemorrhages Cup to Disc Ratio (C.D.) Corneal thickness High IOP s vs. thick cornea Average corneal thickness ~ 550 microns Normal Suspect Glaucoma Current & Past Medical History Personal Hx- General history of previous Tx Family Hx Currently on Tx, (tried drops that did not work, allergy to any drops, any Sx/Tx) Highest eye pressures (TMax) Glaucoma can be hereditary, this makes family history of this disease very important information to ask Head Trauma/Concussion LBP Glaucoma can develop by having a traumatic brain injury or blunt force trauma to eye, causing the eye pressure to increase causing optic nerve damage Lack of blood flow can be associated with optic nerve damage. *Some eye drops can cause a lower heart rate (Beta-Blocker) and with need to be avoided Raynaud s Disease Poor circulation and blood flow can be linked to optic nerve damage Blood Transfusion/Anemia Poor blood circulation can be linked to optic nerve damage for African American patients ask if they have a Hx of Sickle Cell Anemia. These patients should not have CAI eye drops or oral CAI s Sulfa Allergy Not able to have Topical and Oral CAI s COPD/Asthma Lack of oxygen can be associated to optic nerve damage. *Some eye drops can cause a low respiratory rate (Beta-Blocker) and will need to be avoided TONOMETRY Kidney Stones Not able to have Topical and Oral CAI s Hx of Migraines Occluded blood flow causing optic nerve damage 2

Intraocular Pressure Types of Tonometry Tonometry is the measurement of

Indentation Normal range: 8 to 21 mm Hg Higher values can indicate the

Tonometers measure the amount of force needed to flatten the small area

These units measured are called mm Hg Goldmann Applanation Tonometer

oculars Preparing the Patient Obtaining a Measurement Instill the

forehead firmly pressed against the headrest Instruct the patient to look

3 Intraocular Pressure Types of Tonometry Tonometry is the measurement of intraocular pressure (IOP) in millimeters of mercury (mm Hg) Applanation Indentation Normal range: 8 to 21 mm Hg Higher values can indicate the possible presence of Glaucoma Applanation Tonometry Goldmann Applanation Tonometers measure the amount of force needed to flatten the small area of the central cornea (3.06 mm). These units measured are called mm Hg Goldmann Applanation Tonometer Attached to a slit-lamp Uses the light source and one of the microscope oculars Preparing the Patient Obtaining a Measurement Instill the fluorescein drop (Anesthetic) Position patient at the slit-lamp with forehead firmly pressed against the headrest Instruct the patient to look straight ahead The microscope is directed straight ahead The magnification is set on low The Cobalt blue filter is dialed into place 3

Obtaining a Measurement Obtaining a measurement Using the control handle, gently move the prism forward until it just touches the central cornea The spot of

One above and one below The mires should centered in the field and equal in size Slowly turn the pressure dial of the tonometer in the direction required to move

Multiply the number by 10 Obtaining a measurement Source of Errors If the mires are separated the pressure reading will be too low.

4 Obtaining a Measurement Obtaining a measurement Using the control handle, gently move the prism forward until it just touches the central cornea The spot of fluorescein will break into two semi circles (Mires). One above and one below The mires should centered in the field and equal in size Slowly turn the pressure dial of the tonometer in the direction required to move the mires until their inner edges just touch. Multiply the number by 10 Obtaining a measurement Source of Errors If the mires are separated the pressure reading will be too low. If the mires overlap the pressure reading will be too high If the fluorescein band is too wide the pressure reading will be higher than the real intraocular pressure. If the fluorescein band is too narrow the reading will be lower then the real intraocular pressure. Indentation/Applanation Tonometry Tono-pen is a modified form of indentation and applanation tonometry Gently tap 4 times to get reading ERRORS IN TONOMETRY 4

5 Good Readings Fluress Errors Too Low Too High Too Far Right Too Far Left Questions? Tip Turned Look at our goodies. 5

Glaucoma: Diagnostic Modalities

Glaucoma: Diagnostic Modalities - Dr. Barun Kumar Nayak, Dr. Sarika Ramugade Glaucoma is a leading cause of blindness in the world, especially in older people. Early detection and treatment by ophthalmologist