Retinitis Pigmentosa

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Retinitis Pigmentosa
SPE516
Learning Activity 2
Sharla Rosenstein, Vickie Korenek,
Leaundra Ottmo, Lenon Phillips, Pam
Thomas, Patty Boyd
Region 10
Retinitis Pigmentosa
Retinitis pigmentosa is a
rare disease in which
the retina, specifically
the photoreceptor cells
called rods, of the eye
slowly degenerates,
resulting in blindness.
This disease is genetically
based and hereditary.
Symptoms
Retinitis Pigmentosa, also known as RP, is usually
found early in childhood. Beginning
symptoms include difficulty seeing at night
and a reduction in peripheral vision. This is
because the light-sensing cells that are
responsible for vision in low light situations
are gradually deteriorating. As the disease
progresses, only a small area of central vision
remains, along with slight peripheral vision.
Sight of a person with
regular vision.
Sight of a person with
Retinitis Pigmentosa.
Effects on the Visual System
• Tunnel Vision- similar to the effect of looking through a
straw.
• Night Blindness- rod cells are sensitive to low light levels
and these are the first to degenerate.
• Light and Glare Problems- sunlight can cause a “white-out”
debilitating glare.
• Double Vision- tunnel vision interferes with the brain’s
ability to control alignment of the eyes.
• Cataracts
• Decreased Visual Acuity- the macular area may deteriorate
causing a loss of central vision.
• Hearing loss- the combination of RP and hearing loss is
referred to as Usher’s syndrome.
Tests Used For Diagnosis
• Acuity Tests-measure the accuracy of the central vision at
specific distances in specific lighting situations.
• Color Testing-helps determine the status of cone cells, the
retinal cells that interpret color.
• Visual Field Test-uses a machine to measure how much
peripheral vision is available.
• Dark Adaptation Test-measures how well eyes adjust to
changes in lighting. Also helps the doctor better understand
the current function of rod cells, the cells responsible for
night vision.
• ERG Test-The ERG, electroretinogram test, records the
electrical currents produced by the retina due to a light
stimulus. The intensity and speed of the electrical signal
becomes reduced as the photoreceptor cells degenerate.
Visual Aides
• Gottlieb Visual Awareness System- press on field
awareness prisms and reverse telescopes.
• Increased lighting at night.
• Clear glasses for nighttime use.
• Dark plum or amber filters in glasses, often with
side shields. Amber tinted glasses even for inside.
• Magnification devices.
• CCTVs with contrast set to white letters on black
background.
Medications That Could Slow the
Progression of RP
• Vitamin A/beta carotene supplements- studies
have shown evidence that vitamin
supplementation slows the progression of RP.
• Acetazolamide-orally, helps improve visual
function by reducing Macular edema.
• Calcium channel blockers-have shown benefits in
some animal models but not other models.
• Lutein/zeaxanthin-A National Institutes of Health
(NIH) clinical trial is beginning to test the
effectiveness of lutein and zeaxanthin to slow
age-related macular degeneration
Medications with Adverse Effects on
RP
• Isotretinoin (Accutane): A medication used to
treat acne has been reported to worsen night
vision.
• Sildenafil (Viagra): A medication that has been
shown to cause vision changes.
• Vitamin E
Genetics
Retinal cells are among the most specialized cells in the human body
and depend on a number of unique genes to create vision. A
disease-causing mutation in any one of these genes can lead to
vision loss. To date, researchers have discovered over 100 genes
that can contain mutations leading to RP.
RP can be passed to succeeding generations by one of three genetic
inheritance patterns –
• autosomal dominant-an affected parent can have both affected
and unaffected children,
• autosomal recessive-unaffected parents can have both affected
and unaffected children,
• X-linked inheritance-only males are affected, while females carry
the genetic trait but do not experience serious vision loss..
Available Treatments
Retinal Implant Project- goal of this project is to
develop a microelectronic prosthesis to
restore some vision. This project is a joint
effort of MIT, the Massachusetts Eye and Ear
Infirmary, the VA Boston Healthcare System,
and the NanoScale Science & Technology
Facility at Cornell University.
(Retinal Implant Research Group, 2010)
In addition, researchers have identified some of
the genes that cause RP. It is now possible, in
some families, to perform a test on genetic
material from blood and other cells to
determine if members of an affected family
have one of several RP genes.
Related Diseases
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Usher Syndrome
Bardet-Biedl (Laurence-Moon) syndrome
rod-cone dystrophy
Choroideremia
gyrate-atrophy
Leber congenital amaurosis
Stargardt's disease
References
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About Low Vision & Blindness > Vision Disorders > Retinitis Pigmentosa. (2011).
Retrieved July 19, 2011, from Lighthouse International:
http://www.lighthouse.org/about-low-vision-blindness/vision-disorders/retinitispigmentosa/
Bailey, M. H. (2011, May). Retinitis Pigentosa. Retrieved July 17, 2011, from All
About Vision:
http://www.allaboutvision.com/conditions/retinapigment.htm#ixzz1QR5LqgQs
David G Telander, M. P. (2009, August 19). Retinitis Pigmentosa Treatment &
Management. Retrieved July 19, 2011, from Medscape Reference Drugs, Diseases
and Procedures: http://emedicine.medscape.com/article/1227488-treatment
Eye Conditions>Retinitis Pigmentosa. (n.d.). Retrieved July 17, 2011, from
Foundation Fighting Blindness:
http://www.blindness.org/index.php?option=com_content&view=article&id=50&i
temid=67
Retinal Implant Research Group. (2010). Chapter 29. The Retinal Implant Project
RLE> Progress Report 152. Retrieved July 19, 2011, from Research Laboratory of
Electronics at MIT:
http://www.rle.mit.edu/rleonline/ProgressReports/3677_29_PR152.pdf
Richard L. Windsor, O. F., & Laura K. Windsor, O. F. (n.d.). Retinitis Pigmentosa and
Usher's Syndrome. Retrieved July 17, 2011, from http://www.lowvision.org:
http://www.lowvision.org/retinitis_pigmentosa.htm
On October 26, 2009, WPTV News Channel 5 in West Palm
Beach did an interview with Jason Colannino. Jason sings
and plays the guitar and performs regularly at local
nightclubs. He had plans for a great future as a musician.
His plans are coming along nicely. They just took a
different turn than he had planned on.
Jason is in his 30’s at this time. As he is being interviewed,
Jason tells the correspondent he cannot see the
correspondent’s face. He could see the correspondent’s
tie and his shirt. He could see most everything around the
correspondent. But, if Jason looked right at him, he saw a
“dark blur”. If Jason looked to the side, he could see the
correspondent a little better.
Doctors diagnosed Jason with RP in 2005 when Jason started
having trouble seeing. When he went to the doctor, they
took pictures of his eyes and knew something was wrong.
Jason was told the retinal tissue lines the back of the eyes
and transports the images we see to the brain. So, when
the retinal tissue malfunctions, the vision is affected.
When Jason performs at area clubs, the audience isn’t aware
he sees them dark and out of focus. He does not advertise
his condition, which has led to some embarrassing
moments. Jason talks about how people would come to
him after a performance to tell him what a good job he did
and how they loved his music. They would put their hand
out to shake his hand and he would not see their hand.
Jason has had to make adjustments to his day-today life. These adjustments include making the
words bigger on his computer screen, making
the letters larger on the keyboard, and using a
magnifying glass to read. Driving is not an
option. Jason feels he has adapted nicely. He is
hoping scientist will find a cure. He knows there
is a lot of research going on now and that is
where he puts his faith.
I listened to Jason’s music. It is very good. He is
blessed.
I talked to Jason by email on July 21, 2011, to get
an update on his condition, his feelings, etc.
Jason say the main thing that has changed in his
life due to RP, is he lost quite a bit of
independence. He doesn’t drive anymore so he
has to rely on other people to get him to his gigs.
When he goes to a dimly lit or dark place
(movies, restaurants, etc.), he has to be led by his
wife or a friend so he doesn’t walk into things or
fall down steps, or even fall off the stage.
The kind of RP that he was diagnosed with is called
"sporadic" RP. It is not hereditary in his case. It
just happened to him like being hit by lightning.
The doctor thinks it may have been a dormant
gene that woke up. The doctor also says that if
he has kids, they may not even get RP. So, he is
not totally in the dark; he has low vision. He
cannot read a newspaper or any kind of print. He
can navigate the computer. He just blows up the
letters on the screen. He writes bills wearing
high powered, magnifying, eyeglasses. He has to
read the bills with a hand held magnifier, as well.
Most of what he sees is blurry. Eyeglasses do not
help.
As far as treatments, he has been told by his
doctor to keep an eye (“so to speak”) out for
news about research. His doctor seems hopeful
that there will be a treatment in his lifetime.
Actually, what he does is use Google Alerts to
send him RP news every day. He states, in his
case, the doctor seems focused on gene therapy
rather than stem cells.
He is currently taking 40mg of Lutein daily. Also,
his doctor told him to up his dosage of dark
green veggies.
His advice on talking with parents/students/individuals about RP is
“get involved”. Learn about RP, stay informed; learn about vision
aides. There are many organizations that can supply vision aides
for free. Go to seminars, do the research about treatments as
well. His personal opinion is, because technology is changing
drastically and so quickly, everything is getting smaller; iPhones ,
Androids, Blackberry’s, even news print has gotten smaller. He
feels everybody, at some point, may develop some sort of vision
problem. He feels researchers may want to get on top of this
because the corporations responsible wont want people to stop
buying their products. He states “maybe the corporations will
strike a deal with researchers so eventually blindness may
become a thing of the past”.
His music career is doing very well. He has been playing music
for a living since 1992. He performs six nights a week right now.
He is starting to record his third CD.
http://www2.wptv.com/dpp/news/region_s_palm_beach_county/b
oynton_beach/Local-musician-losing-his-eyesight-to-R.P
Interview with Jason Colannino from Channel 5
WPTV , South Forida.
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AMERICAN FOUNDATION FOR THE BLIND
Southwest Regional Center
11030 Ables Lane
Dallas, TX 75229
214-352-7222 1-800-232-5463 www.afb.org
DARS DIVISION FOR BLIND SERVICES
6500 Greenville Avenue, Suite 250
Dallas, TX 75206
1-800-628-5115 www.dars.state.tx.us
Fort Worth
Our Special Children for parents of children with developmental
delays, meets the second Saturday of every month from 9:30 11:30 a.m. at the Cooks Children's Medical Center.
Contact: Emma Bell at (817) 265-6009.
National
National Parent to Parent Support and Information
System
PO Box 907
Blue Ridge, GA 30513
1-800-651-1151 (voice/TTY)
(706) 632-8822 (voice/TTY)
(706) 632-8830 (fax)
http://www.nppsis.org
National Organization of Parents of Blind Children
1800 Johnson St.
Baltimore, MD 21230
(410) 659-9314 (voice)
(612) 696-1975 (BBS)
(410) 685-5653 (fax)
http://www.nfb.org
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STATE / REGIONAL
Deaf-Blind Multihandicapped Association of Texas
(DBMAT)
815 High School Dr.
Seagoville, TX 75159
(214) 287-1904
Texas Department of Assistive and Rehabilitative Services
(formerly known as Texas Commision for the Blind) &
Visually Impaired Children's Program
4800 North Lamar
Austin, Texas 78756
1-800-252-5204
(512) 459-2549
http://www.dailystrength.org/c/Retinitis_Pigmentosa/foru
m/12469034-im-new-and
http://www.mdjunction.com/forums/retinitispigmentosa-discussions/introductions-personalstories/1551660-ssd
Wind Chimes
Metronome
Electronic locators with Braille touch pads
Ocular Motility Test
Visual field test
Refraction test
The following is a list of materials and tools that can be
helpful to students who are visually impaired:
 Low vision exams
 Refraction (asses vision and whether glasses are needed)
 Visual Field (asses peripheral vision)
 Ocular motility (asses eye movement)
Tools that assist with distance recognition
 (These items can be strategically placed to help identify
important locations and/or materials)
 Wind Chimes
 Metronomes
 Electronic locators
Reading aides
 Large print books
 Computer –based text magnifiers
 Desk lamps
 Audio books
Click on the following links.
Retinal Implants
Brain Port
Stem Cell Cure
Stem Cell Cure2
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This is a rare, inherited disease in which the light-sensitive
retina of the eye slowly and progressively degenerates. The
degeneration of the retina, eventually, causes blindness.
Retinitis pigmentosa occurs in about 1 of every 4,000
people in the United States.
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Visual field testing is usually conducted, during or after a
routine eye exam, when retinitis pigmentosa is suspected.
This is done in order to determine whether there is and the
severity of the impact on peripheral vision. Other
specialized tests may be needed to determine whether there
is a loss of night or color vision.
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Symptoms
Symptoms of retinitis pigmentosa usually occur in early childhood.
Both eyes are typically affected as the light-sensing cells that are
responsible for vision in dim light (rods) gradually deteriorate. When
this occurs night vision becomes more difficult.
During later stages of retinitis pigmentosa, only a small area of central
vision and slight peripheral vision remains.
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The vision loss and/or the rate that it progresses of a person with
retinitis pigmentosa is usually unpredictable. The consumer’s eye
doctor will usually monitor the health of the consumer’s retinal cells
and administer tests to determine the his/her level of vision.
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Causes
The causes of retinitis pigmentosa are relatively unknown. The eye
disease is genetic and passed along through both dominant and
recessive traits.
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Treatments
Currently there is no cure for retinitis pigmentosa. But several companies are developing retinal implants and other innovative treatments
that are showing promise in providing or preserving some degree of usable sight for people affected by RP. The potential treatments
include:
1. Argus II Retinal Prosthesis System. Second Sight Medical Products (Sylmar, Calif.) is developing the Argus II Retinal
Prosthesis System for patients blinded by retinitis pigmentosa and other degenerative retinal diseases.
The Argus II system consists of a tiny video camera that is built in to a special pair of eyeglasses. The camera is connected to a small,
wireless device worn by the patient, which coverts the video input to electronic signals that are transmitted wirelessly to the implant in
the eye. The implant uses this information to stimulate remaining healthy cells in the retina and transmits it by the optic nerve to the
brain, where it is perceived as patterns of light. The patient learns to interpret these patterns so he or she can distinguish the outlines of
objects. The cost of the system is approximately $100,000, and may be covered by medical insurance. The Second Sight is planning to
submit the Argus II system for FDA review in the second half of 2011 and hopes to obtain approval to market the product in the United
States in 2012.
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2. Retina Implant AG. A microchip implanted into the eye absorbs light signals; transforms them into electrical impulses;
amplifies them; and transmits them through the eye's optic nerve to the brain. Estimated the cost of the company's device would
be about $200,000.
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3. Electrical Stimulation Therapy. For patients with early and intermediate-stage RP, electrical stimulation therapy (EST) of the
eye may help preserve vision that otherwise would be lost to the disease, according to representatives of Okuvision, a German
medical device company founded by Retina Implant AG, at the 2011 ARVO meeting.
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In a clinical trial of 24 patients with early or mid-stage retinitis pigmentosa that began on 2007, eyes that received small amounts of
electrical current delivered to the retina via a tiny electrode showed a significant improvement in field of vision, compared with eyes that
did not receive the stimulation. According to the researchers, the study suggests controlled electrical stimulation of the retina releases
growth factors which may delay degeneration of the retina from RP.
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4. Adaptive Therapy and Low Vision Devices
Early intervention with occupational therapy may be helpful to manage life changes caused by RP, because it's easier to adjust to
declining vision in earlier stages of vision loss.
Individuals with retinitis pigmentosa also might consider use of low vision devices that can help magnify and illuminate objects in home
and work spaces.
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Other treatments. Other possible treatments for RP that are being
Link to Prezi.com presentation
http://prezi.com/fopv2gwghaw_/reti
nitis-pigmentosa/
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