The Eye and Eye Diseases. The Eye and Eye Diseases. STATS 19 SEM 2. 263057202. STATS 19 SEM 2. 263057202.

Talk 7.Talk 7.

A.L. Yuille.A.L. Yuille.

Dept. Statistics. Dept. Statistics. yuille@stat.ucla.eduyuille@stat.ucla.edu

Neural Prostheses.Neural Prostheses.

• Forms of Neural Prostheses already Forms of Neural Prostheses already used. (Simpler than last week). CNN used. (Simpler than last week). CNN story.story.

• Brain messages transmitted to nerve Brain messages transmitted to nerve ends on pectoral muscles of the ends on pectoral muscles of the chest.chest.

• Thoughts cause chest muscles to Thoughts cause chest muscles to contract, activate prosthetic arm.contract, activate prosthetic arm.

Mike May’s and OthersMike May’s and Others

• Project Prakash (light). Pawan Sinha (MIT).Project Prakash (light). Pawan Sinha (MIT).• Sinha studies how children’s brain adapt to Sinha studies how children’s brain adapt to

years of blindness followed by sight.years of blindness followed by sight.• Studies in India. Children have cataract Studies in India. Children have cataract

surgery.surgery.• Sinha “Merely treating the eyes is not Sinha “Merely treating the eyes is not

enough. No one knows if the visual modality enough. No one knows if the visual modality will reclaim areas in the brain that it lost to will reclaim areas in the brain that it lost to other senses during blindness”.other senses during blindness”.

• Some patients commit suicide after Some patients commit suicide after recovered sight. recovered sight.

Mike Mays and OthersMike Mays and Others

• India has the world’s largest India has the world’s largest population of blind children. 100,000 population of blind children. 100,000 children.children.

• 20% have Cataracts, which can be 20% have Cataracts, which can be treated.treated.

• Poverty, inter-marriage to blind Poverty, inter-marriage to blind relatives, diet,…relatives, diet,…

Mike May and Others.Mike May and Others.

• Mondloch (McMaster). Mondloch (McMaster).

• Children with cataracts in the left-eye, Children with cataracts in the left-eye, can recognize faces after surgery.can recognize faces after surgery.

• Children with cataracts in the right-Children with cataracts in the right-eye, cannot. eye, cannot.

• But probably too late if surgery But probably too late if surgery happens 2 months after birth.happens 2 months after birth.

Brain-imaging.Brain-imaging.

• Brain imaging (FMRI) show that neural Brain imaging (FMRI) show that neural areas in the brain devoted to vision can areas in the brain devoted to vision can perform different functions for the blind.perform different functions for the blind.

• Vision area – Touch area.Vision area – Touch area.• Increased activity in the Visual Cortex Increased activity in the Visual Cortex

when blind subjects “read” by using when blind subjects “read” by using Braille.Braille.

• Areas of the Visual Cortex get activated Areas of the Visual Cortex get activated when blind patients remember words and when blind patients remember words and do other verbal memory tasks. (Normal do other verbal memory tasks. (Normal subjects use language areas).subjects use language areas).

The Big Three Eye Diseases.The Big Three Eye Diseases.

• CataractsCataracts

• GlaucomaGlaucoma

• Age-Related Macular Degeneration.Age-Related Macular Degeneration.

The EyeThe Eye

• AnatomAnatomy.y.

The EyeThe Eye

• Imaging and the Lens.Imaging and the Lens.

The EyeThe Eye

• Photoreceptors: Photoreceptors: Rods and Cones.Rods and Cones.

The EyeThe Eye

• Where things go wrong:Where things go wrong:• (I) The Lens (focuses light). (I) The Lens (focuses light). • Lens structure can change. (Cell growth, Lens structure can change. (Cell growth,

protein changes). Cataracts.protein changes). Cataracts.• (II) Eye contains fluids. The pressure of the (II) Eye contains fluids. The pressure of the

fluid can get high (insufficient drainage). fluid can get high (insufficient drainage). This affects nerve cells. Glaucoma.This affects nerve cells. Glaucoma.

• (III) Retina failure. Age-Related Macular (III) Retina failure. Age-Related Macular Degeneration.Degeneration.

Cataracts.Cataracts.

• With age, the Lens enlarges and the With age, the Lens enlarges and the protein structure changes (e.g. lens protein structure changes (e.g. lens can go yellow). Most people over 65 can go yellow). Most people over 65 have some cataracts.have some cataracts.

• Symptoms: Poor distance vision, Symptoms: Poor distance vision, blurred vision, frequent prescription blurred vision, frequent prescription changes, poor night vision, glare, changes, poor night vision, glare, halo around lights, double vision.halo around lights, double vision.

Cataracts.Cataracts.

• The Lens.The Lens.

Cataracts.Cataracts.

• Risk Factors:Risk Factors:• Age, Diabetes, Women/Men, Race, Age, Diabetes, Women/Men, Race,

Developing countries near the Developing countries near the Tropics, Hereditary, Smoking, Some Tropics, Hereditary, Smoking, Some Medications, Excessive sunlight.Medications, Excessive sunlight.

• Second sight: vision appears to get Second sight: vision appears to get better, but then gets far worse.better, but then gets far worse.

CataractsCataracts

• Surgery is Effective. (These days).Surgery is Effective. (These days).

• Glass is well-tolerated by the Eye (2Glass is well-tolerated by the Eye (2ndnd World War).World War).

• Remove parts of Lens (by Remove parts of Lens (by Microsurgery).Microsurgery).

• Implant plastic.Implant plastic.

• Outpatient: go home the same day.Outpatient: go home the same day.

GlaucomaGlaucoma

• Glaucoma “silent thief of vision”.Glaucoma “silent thief of vision”.

• Very difficult to detect. Accounts for Very difficult to detect. Accounts for 12% new blind cases in the US each 12% new blind cases in the US each year.year.

• Start by gradually losing peripheral Start by gradually losing peripheral vision. This causes irreversible damage.vision. This causes irreversible damage.

• Regular Eye exams. Diagnose pressure Regular Eye exams. Diagnose pressure in the eyes.in the eyes.

GlaucomaGlaucoma

• Glaucoma is a collection of different eye Glaucoma is a collection of different eye problems. problems.

• All raise the pressure of liquid inside the All raise the pressure of liquid inside the eye.eye.

• The Eye is basically hollow, like a balloon. The Eye is basically hollow, like a balloon. It contains fluid that helps keep its shape.It contains fluid that helps keep its shape.

• New fluid comes in, old fluid is drained out.New fluid comes in, old fluid is drained out.• But sometimes the drain gets blocked – But sometimes the drain gets blocked –

raises fluid pressure, damages the optic raises fluid pressure, damages the optic nerve (irreversible). Glaucoma.nerve (irreversible). Glaucoma.

GlaucomaGlaucoma

• Draining.Draining.

GlaucomaGlaucoma

• Recall, the image is formed by the Rods Recall, the image is formed by the Rods and Cones on the retina.and Cones on the retina.

• These send nerve impulses to the brain via These send nerve impulses to the brain via the Optic Nerve. The Optic Nerve starts at the Optic Nerve. The Optic Nerve starts at the Optic Disk.the Optic Disk.

• High fluid pressure in the Eye damages the High fluid pressure in the Eye damages the Optic Disk. Exact mechanism is unknown. Optic Disk. Exact mechanism is unknown.

• Peripheral vision is often lost before Peripheral vision is often lost before patients are aware of it. patients are aware of it.

GlaucomaGlaucoma

• Optic Nerve.Optic Nerve.

GlaucomaGlaucoma

• Treatment.Treatment.

• Lower the fluid pressure.Lower the fluid pressure.

• Eye drops, drugs, lasers, surgery.Eye drops, drugs, lasers, surgery.

• Risk factors: Age, Hereditary, Race Risk factors: Age, Hereditary, Race (African Americans).(African Americans).

Age-Related Macular Age-Related Macular Degeneration.Degeneration.

• Least understood.Least understood.• Ageing of the outermost layer of the Ageing of the outermost layer of the

Retina.Retina.• Progressive degenerate changes in Progressive degenerate changes in

the epithelium cells, photoreceptors the epithelium cells, photoreceptors (rods and cones).(rods and cones).

• Major cause of blindness in US, Major cause of blindness in US, England, Canada.England, Canada.

Age-Related Macular Age-Related Macular Degeneration.Degeneration.

• Cells on retina.Cells on retina.

Age-Related Macular Age-Related Macular Degeneration.Degeneration.

• Risk Factors.Risk Factors.

• Women/Men, Heredity, Blue eyes – Women/Men, Heredity, Blue eyes – particularly Caucasians, smoking, particularly Caucasians, smoking, high blood pressure, sunlight.high blood pressure, sunlight.

• Treatment is limited. Some forms Treatment is limited. Some forms respond to lasers, surgery,…respond to lasers, surgery,…

General Health Care.General Health Care.

• Diabetes – major cause of blindness Diabetes – major cause of blindness among working people in US.among working people in US.

• Increases risk for Cataracts and Increases risk for Cataracts and Glaucoma. But also damages the Glaucoma. But also damages the retina directly.retina directly.

• Main risk factor for Diabetes – high Main risk factor for Diabetes – high blood sugar. blood sugar.

General HealthGeneral Health

• High-Blood Pressure (Hypertension). High-Blood Pressure (Hypertension). Damages the blood arteries in the retina.Damages the blood arteries in the retina.

• AIDS/HIV. Affects the immune system. AIDS/HIV. Affects the immune system. Microorganisms CMV (Cytomegalovirus).Microorganisms CMV (Cytomegalovirus).

• CMV attacks the retina of about 30% CMV attacks the retina of about 30% people with AIDS. Destroys tissue, causes people with AIDS. Destroys tissue, causes bleeding, retinal detachment. bleeding, retinal detachment.

Alan Scott and BotoxAlan Scott and Botox

• Botox was developed by an Eye Botox was developed by an Eye Surgeon – Alan Scott.Surgeon – Alan Scott.

• It is used to relax eye muscles and It is used to relax eye muscles and allow eyes to track objects.allow eyes to track objects.

• He sold the idea to a company for He sold the idea to a company for development. Later, the company development. Later, the company realized that Botox could be used for realized that Botox could be used for cosmetics.cosmetics.

Traditional Low-Vision Traditional Low-Vision Devices.Devices.

• Low tech.Low tech.

• Hand-held magnifiers.Hand-held magnifiers.

• Telescopes.Telescopes.

SummarySummary

• Review of the Eye.Review of the Eye.

• Three Major Eye Diseases: Cataracts, Three Major Eye Diseases: Cataracts, Glaucoma, Age-Related Macular Glaucoma, Age-Related Macular Degeneration.Degeneration.

• First two treatable, if Glaucoma First two treatable, if Glaucoma detected early enough.detected early enough.

• Major advances in treatment.Major advances in treatment.