Revitalization of Retinal Tissue

Over the past several years, many different approaches have been taken to try to revitalize retinal tissue.  The two most active are microchip technology and stem cell technology.  Microchip technology tries to stimulate attached damaged retinal tissue by electrical stimulation to cause a visual image for the patient.  The second approach is to try and use stem cells to rebuild retinal tissue in hopes that function may follow.  The purpose of this article is to give an update on the existing microchip and stem cell projects.

Microchips have been used in the United States in patients with severe retinitis pigmentosa.  Retinitis pigmentosa leaves the retina atrophic and the optic nerve pale, the retinal vessels small in caliber, and the outer retina, including the outer segments of the rods and cones and the tissue immediately beneath the retina (the retinal pigment epithelium), mottled.  This physical appearance is very similar to eyes that have had their retinas reattached following severe retinopathy of prematurity, as well as familial exudative vitreoretinopathy.  These eyes, with damaged outer retina and yet still functional inner retina, may be able to be revitalized by stimulating the retina with a patterned electrical stimulation.  This stimulation resembles an object that is being presented to a camera mounted on spectacles and results in electrical stimulus causing the retina to send a signal to the brain.  The brain interprets this as an image.  A simulation of this type can be performed by rubbing the eye with the eyelids closed.  This gives a bright flash that is called a phosphene.  These phosphenes, in appropriate patterns, can be interpreted by patients as shapes and objects.  This visual precept is something which can be very useful if the patient has only light perception vision or no light perception.  The resolution of these precepts may be able to be refined to the point where a more defined visual precept is possible, simulating frank vision.  These projects are still many years from being available to children affected with many of the pediatric retinal diseases.

Stem cells have shown very interesting physical changes in animal models to date and some forms of electrophysiologic testing suggest that function may follow this change in anatomy.  The most intriguing form of animal stem cell projects involve the use of stem cells from the animal’s own bone marrow, autologous hemopoietic stem cells.  These stem cells show structural changes in animal models, which contribute to thickening of the retina and an increase in retinal vasculature that may translate into functional changes in these animal populations.  Stem cells have been considered for use in other diseases such as ischemic cardiac disease and hopefully soon human trials with stem cells will be underway.  Again, it will probably be several years before this type of therapy will be something that may be usable in children’s retinal diseases.   It is however encouraging that so many investigators are now working in an area to try and revitalize this retinal tissue, which for so many years has been thought to have no future viability.

A Visit With the VanHoutens

They are curious, talkative, active.  You may remember that we first met them in an article we published in the December 2004 issue of Sightlines.  The VanHoutens will be three years old in January.  Kennedy, Peyton, Gerrit, Samantha, John, and Nolan have all grown into typical two year olds, and, yes, the concept of sharing is still a challenge when you are one of six.  This fall, a new sister arrived on the scene, Drew Riley weighed in at nine pounds—the total of her siblings birth weights. 

            The sextets continue to have a busy schedule.  Three days a week, John and Gerrit attend school while the other four go to a toddler play group.  Like other children their age, they all love books and being read to, coloring, and playing outdoors on their play set.  All of them follow their individual paths, as their character dictates. 

Although visits to doctors are less frequent, they do see their ophthalmologists.  Crossed eyes, treated with patches are one problem.  Peyton and John are having eye surgery in the next month to correct superior oblique palsy and crossing.  Gerrit has eye delay but his eyes are healthy and they are hoping it will correct itself.

The VanHoutens, under the guidance of Amy and Ben, continue to thrive.  No doubt, challenges will be met with the same grace and intelligence in the years to come.   

World ROP Meeting  (with photo of the 2 Rasas)

On September 14-16, 2006, the World ROP Meeting was held in Vilnius, Lithuania.  The Screening and Management of ROP in several countries around the world was discussed.  The meeting was attended by 250 participants from fifty countries.

Crain’s Health Care Heros/Outstanding Physician Achievement

Every year, Crain’s business magazine honors individuals for outstanding achievements in the field of Health Care.  There are four categories of Health Care Heroes: outstanding physician achievement, outstanding advancement in health care, contributions in allied health care, and corporate achievement.  This year, Dr. Michael Trese was honored for outstanding physician achievement.  The honor recognizes the work Dr. Trese has done in creating ROPARD to direct research money to eliminate vision problems and blindness due to pediatric retinal diseases.

Simon Bonenfant

Simon came into the world four years ago, a bit earlier than planned.  He was born at 24 weeks, weighing one pound, 3.6 ounces (the .6 is very important when you are that size).  He grew steadily in the NICU, but a routine eye exam showed that ROP was developing and both eyes were in Stage 3.  Laser surgery was performed but the disease progressed rapidly to Stage 5—retinal detachment in both eyes.  A second opinion from a local doctor was not encouraging.  Although Simon was tiny, he had shown a strong will to live, so his parents, Marie Ceferatti and Ron Bonenfant, searched for help and found Dr. Trese.

Dr. Trese gave the family a good understanding of the situation and over the next four years, they have made dozens of trips to Detroit.  After a lensectomy in each eye and three vitrectomies, Simon’s retinas are partially attached but there is still some detachment in each eye.  Simon has light perception and light projection—qualities that will help to orient him in a room and to navigate in his environment.  He wears contact lenses to help focus any available light that he can see and glasses to protect his eyes from injury.

Simon lives in Philadelphia and is in Pre-K at Saint Lucy’s Day School for the Visually Impaired.  Saint Lucy’s partners with a school for the sighted called Holy Innocence.  The program at Saint Lucy’s includes Braille instruction (which Simon will use as his primary reading method), orientation and mobility, and low-vision technology training.  Once he reaches the first grade, Simon will be gradually mainstreamed with the sighted first graders at Holy Innocence.  He will receive the training that he needs, while also learning with his sighted peers. 

Simon is slowly becoming independent—he knows how to dress himself (with verbal prompts), he walks with a cane, and he talks up a storm!  With a lively sense of humor, he exudes a love of life.  Music is a major interest, and he plays both the ukulele and the guitar, accompanying his grandfather who plays the sax.  He enjoys sports, plays golf and tennis, and follows baseball and football.  Simon’s teachers and therapists encourage him to learn new skills, explore his environment, and advocate for himself.  As much as he learns from those around him, Simon contributes as well.  While vision can be helpful, a strong spirit is the gift that truly leads the way