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Welcome to the Retinitis
Pigmentosa File
Patients all over the world
have used the information in The Retinitis Pigmentosa File since
1992, when the Center for Current Research—one of the first
80 companies on the Internet—was founded. Our highly trained
researchers (all of whom hold Ph.D.s) have searched the advanced
medical database at the National Library of Medicine and compiled
a comprehensive collection of research descriptions on Retinitis
Pigmentosa and its care.
As you will see, the following research descriptions detail the
findings published in the most respected journals in the field.
Because the research descriptions are written in medical terms,
most people will bring all or parts of the Retinitis Pigmentosa
File to their doctor for further explanation and discussion.
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other information that could be useful in planning a successful
course of treatment and prevention. Note that the titles of the
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Medicine's format; your doctor can provide the full title if
you need it.
Thank you for accessing the Retinitis Pigmentosa File. We truly
hope the information fosters better health.
Sincerely,
Gregory A. Fraser, Ph.D.
Director of Research
Important Note: The following information
is provided for your education. It should not be relied upon for
personal diagnosis or treatment. If you believe that a
particular therapy applies to you or someone you care about, be
sure to consult a doctor before trying it.
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Latest Research on
Retinitis Pigmentosa
Clin Exp Optom. 2008 Mar;91(2):166-76.
Reported effects of non-traditional treatments and complementary and alternative
medicine by retinitis pigmentosa patients.
Kiser AK, Dagnelie G.
Johns Hopkins University, Wilmer Eye Institute, Baltimore MD, USA. abittne1@jhmi.edu
BACKGROUND: Benefits of complementary and alternative medicine (CAM)-related
interventions have been demonstrated for patients with chronic, systemic
diseases in which stress, anxiety and disability are prevalent. Subjects with
retinitis pigmentosa (RP) commonly indicate that they have 'good' and 'bad'
vision days, stating that stress causes a decrease in vision and that vision
improves when the stress is alleviated. We assessed CAM use by RP patients and
its perceived effectiveness. METHODS: We enquired about nine CAM areas:
meditation, mind-body therapies, yoga, movement therapies, energy therapies,
acupuncture, massage therapy, spirituality/religion and herbal
therapies/aromatherapy. Ninety-six RP patients with any level of vision
completed an anonymous internet survey. RESULTS: Ninety-five per cent of
respondents tried at least one of the nine CAM areas. Seventy-five per cent have
used nutritional supplements, including lutein (47 per cent), bilberry (32),
vitamin A palmitate (36) and docosahexaenoic acid (23 per cent). Some tried meditation (47) and
yoga (31 per cent). Stress and anxiety levels were reported as improved in 93,
92 and 87 per cent of those who used yoga, meditation and mind-body therapies,
respectively. Many of those who tried mind-body therapies (40) or acupuncture
(50 per cent), used it with a desire to fight RP. Vision was subjectively
affected in 65 per cent of acupuncture users and from 20 to 35 per cent of the
users of the other CAM areas. Those who indicated that their vision was affected
by at least one type of CAM (35 per cent) were statistically significantly more
likely to require magnification to read (that is, they had lost more vision and
RP had progressed), than those who did not believe vision was impacted (59
versus 84 per cent). CONCLUSIONS: RP patients are using CAM and are experiencing
some impact on vision and physical/emotional well-being. Clinicians and
researchers should be aware of its use. Clinical trials with CAM interventions are necessary to attempt to validate these
findings.
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J Ocul Pharmacol Ther. 2008 Jan 17 [Epub ahead of print]
A Pilot Study of Topical Treatment with an alpha(2)-agonist in Patients with
Retinal Dystrophies.
Merin S, Obolensky A, Farber MD, Chowers I.
Department of Ophthalmology, Hadassah-Hebrew University Medical Center,
Jerusalem, Israel.
Purpose: The aim of this study was to assess the neuroprotective effect of a
topical alpha(2)-agonist in patients with retinal dystrophies. Methods: This
study was a prospective, placebo-controlled, double-masked, randomized clinical
trial. A total of 26 patients with retinal dystrophies were included. One (1)
randomly selected eye was treated with brimonidine tartrate 0.2% twice-daily,
while the fellow eye received artificial tears. Disease progression parameters
tested at 6-8-month intervals throughout the study included Goldmann visual
fields, contrast sensitivity, color vision, and fullfield electroretinography.
Results: Seventeen (17) of the 26 recruited patients completed the study. Except
for 1 patient with an 18-month follow-up, all patients were followed up for
24-36 months (mean, 29). At the conclusion of the study, there were no
differences detected in visual acuity, color vision, and contrast sensitivity
between the treated and control eyes. There was a trend, however, toward a lesser degree of visual field loss in the brimonidine-treated
eyes. There was also a delay in the time required to reach a 25% visual field
loss in the treated eyes. These differences were more pronounced in a subgroup
of patients diagnosed as retinitis pigmentosa and with visual fields of 5 cm(2)
or more at baseline. Conclusions: The findings of this pilot study suggest a
trend for slower progression in the eyes of patients with retinal dystrophy when
treated with brimonidine, according to one of the parameters that was studied
(visual field loss). Further studies that include a larger number of patients
and a longer follow-up period are needed to clarify and confirm the potential
neuroprotective effect of alpha(2)-agonists in human retinal dystrophies.
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Clin Exp Optom. 2008 Jan;91(1):78-84.
A review of the potential to restore vision with stem cells.
Mooney I, Lamotte J.
Southern California College of Optometry, Fullerton, California, USA.
Vision research involving stem cells is a rapidly evolving field. Animal
experiments have shown that in response to environmental cues, stem cells can
repopulate damaged retinas, regrow neuronal axons, repair higher cortical
pathways, and restore pupil reflexes, light responses and basic pattern
recognition. Viable corneas have been grown from stem cells and transplanted
into humans. Similarly, human trials to repair damaged retinas in retinitis
pigmentosa and age-related macular degeneration patients have produced
preliminary successes. This review attempts to place the collective
contributions toward stem cell/vision research into a broader clinical model of
how stem cells might ultimately be used to restore the entire visual pathway.
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J Biomater Sci Polym Ed. 2007;18(8):1031-55.
Retinal prostheses: current challenges and future outlook.
Winter JO, Cogan SF, Rizzo JF 3rd.
Center for Innovative Visual Rehabilitation, VA Medical Center, Boston, MA, USA.
winter.63@osu.edu
Blindness from retinal diseases, including age-related macular degeneration
(AMD) and retinitis pigmentosa (RP), usually causes a significant decline in
quality of life for affected patients. Currently there is no cure for these
conditions. However, over the last decade, several groups have been developing
retinal prostheses which hopefully will provide some degree of improved visual
function to these patients. Several such devices are now in clinical trials.
Unfortunately, the possibility of electrode or tissue damage limits excitation
schemes to those that may be employed with electrodes that have relatively low
charge densities. Further, the excitation thresholds that have been required to
achieve vision to date, in general, are relatively high. This may result in part
from poor apposition between neurons and the stimulating electrodes and is
confounded by the effects of the photoreceptor loss, which initiates other
pathology in the surviving retinal tissue. The combination of these and other
factors imposes a restriction on the pixel density that can be used for devices
that actively deliver electrical stimulation to the retina. The resultant use of
devices with relatively low pixel densities presumably will limit the degree of
visual resolution that can be obtained with these devices. Further increases in
pixel density, and therefore increased visual acuity, will necessitate either
improved electrode-tissue biocompatibility or lower stimulation thresholds. To
meet this challenge, innovations in materials and devices have been proposed.
Here, we review the types of retinal prostheses investigated, the extent of
their current biocompatibility and future improvements designed to surmount
these limitations.
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Acta Neurochir Suppl. 2007;97(Pt 2):487-93.
Towards the bionic eye--the retina implant: surgical,
opthalmological and histopathological perspectives.
Alteheld N, Roessler G, Walter P.
Department of Ophthalmology, RWTH Aachen University, Aachen, Germany. nalteheld@ukaachen.de
Degenerations of the outer retina such as retinitis pigmentosa (RP) lead to
blindness due to photoreceptor loss. There is a secondary loss of inner retinal
cells but significant numbers of bipolar and ganglion cells remain intact for
many years. Currently, no therapeutic option to restore vision in these blind
subjects is available. Short-term pattern electrical stimulation of the retina
using implanted electrode arrays in subjects blind from RP showed that
ambulatory vision and limited character recognition are possible. To produce
artificial vision by electrical retinal stimulation, a wireless intraocular
visual prosthesis was developed. Images of the environment, taken by a camera
are pre-processed by an external visual encoder. The stimulus patterns are
transmitted to the implanted device wirelessly and electrical impulses are
released by microcontact electrodes onto the retinal surface. Towards a human
application, the biocompatibility of the utilised materials and the feasibility
of the surgical implantation procedure were stated. In acute stimulation tests,
thresholds were determined and proved to be within a safe range. The local and
retinotopic activation of the visual cortex measured by optical imaging of
intrinsic signals was demonstrated upon electrical retinal stimulation with a
completely wireless and remotely controlled retinal implant. Potential obstacles
are reviewed and further steps towards a successful prosthesis development are
discussed.
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Acta Neurochir Suppl. 2007;97(Pt 2):481-6.
A neuroprosthesis for restoring sight.
Viola MV, Patrinos AA.
Office of Biological and Environmental Sciences, United States Department of
Energy, Germantown, MD, USA.
Macular degeneration (MD) and retinitis pigmentosa (RP), two diseases that cause
degeneration of retinal photoreceptor cells, are the leading causes of blindness
in the United States. Anatomical studies have shown that other retinal neuronal
cells (bipolar cells, ganglion cells) are preserved in these diseases and they
are capable of eliciting visual percepts when electrically stimulated. We
describe the design of a prototype 16-electrode retinal prosthesis, and the
physiological and clinical results on six blind patients with RP who had the
device implanted. The US Department of Energy artificial retina program is
described. The goal of the program is construction of a 1000-electrode retinal
neuroprosthesis with the potential of enabling blind patients to read large
print and ambulate with ease.
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Acta Neurochir Suppl. 2007;97(Pt 2):465-72.
Implantable visual prostheses.
Thanos S, Heiduschka P, Stupp T.
Department of Experimental Ophthalmology, University Eye Hospital and
Interdisciplinary Centre of Clinical Research (IZKF), Münster, Germany. solon@uni-muenster.de
Visual impairment and blindness is primarily caused by optic neuropathies like
injuries and glaucomas, as well as retinopathies like agerelated macular
degeneration (MD), systemic diseases like diabetes, hypertonia and hereditary
retinitis pigmentosa (RP). These pathological conditions may affect retinal
photoreceptors, or retinal pigment epithelium, or particular subsets of retinal
neurons, and in particular retinal ganglion cells (RGCs). The RGCs which connect
the retina with the brain are unique cells with extremely long axons bridging
the distance from the retina to visual relays within the thalamus and midbrain,
being therefore vulnerable to heterogeneous pathological conditions along this
pathway. When becoming mature, RGCs loose the ability to divide and to
regenerate their accidentally or experimentally injured axons. Consequently, any
loss of RGCs is irreversible and results to loss of visual function. The advent
of micro- and nanotechnology, and the construction of artificial implants
prompted to create visual prostheses which aimed at compensating for the loss of
visual function in particular cases. The purpose of the present contribution is
to review the considerable engineering expertise that is essential to fabricate
current visual prostheses in connection with their functional features and
applicability to the animal and human eye. In this chapter, 1) Retinal and
cortical implants are introduced, with particular emphasis given to the
requirements they have to fulfil in order to replace very complex functions like
vision. 2) Advanced work on material research is presented both from the
technological and from the biocompatibility aspect as prerequisites of any
perspectives for implantation. 3) Ultimately, experimental studies are presented
showing the shaping of implants, the procedures of testing their
biocompatibility and essential modifications to improve the interfaces between
technical devices and the biological environment. The review ends by pointing to
future perspectives in the rapidly accelerating process of visual prosthetics
and in the increasing hope that restoration of the visual system becomes
reality.
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Graefes Arch Clin Exp Ophthalmol. 2007 Aug 3; [Epub ahead of print]
Slowing the degenerative process, long lasting effect of
hyperbaric oxygen therapy in retinitis pigmentosa.
Vingolo EM, Rocco M, Grenga P, Salvatore S, Pelaia P.
Inherited Degenerative Retinal Diseases Unit, Department of Ophthalmology,
Policlinico Umberto I, University of Rome “La Sapienza”, Rome, Italy.
BACKGROUND: Retinitis pigmentosa (RP) therapy is still an unsolved challenge.
Recent reports have underlined that hyperbaric oxygen (HBO) therapy could play a
role in slowing the retinal degenerative process. The aim of this study was to
assess the efficacy of HBO therapy on visual function in RP patients. METHODS:
We performed a single-center, comparative, longitudinal case-controlled
randomized clinical trial, which lasted 10 years. We randomly divided RP
patients into two groups. Group 1, the control group, consisted of 44 RP
patients (21 males and 23 females; mean age 35.5) who took Vitamin A. Group 2,
with 44 RP patients (21 males and 23 females; mean age 35,02), underwent HBO
therapy. No statistically significant difference was found at the beginning of
the study between the two groups. We compared the results concerning visual
acuity, Goldmann perimetry, static perimetry Humphrey field analyzer (HFA), and
electroretinogram (ERG) obtained in the two groups at 5 and 10 y
ears follow-up. Statistical analysis was performed with Kaplan-Meier life-table
with the evaluation of log-rank coefficient. RESULTS: At 5 year follow-up, 87.5%
of group 2 patients preserved 80% of the initial visual acuity, while the same
result was achieved in only 70.4% of group 1 patients (X(2) = 8.2; p < 0.01); at
10 year follow-up, 63.33% of group 2 patients preserved 80% of the initial
visual acuity, while the same percentage of residual visual acuity was
maintained in 40% of group 1 patients (X(2) = 3.22; p = 0.05). At 10 year
follow-up, Goldmann perimetry (target I4e) did not change in 31.6% of group 2
and in 10.5% of group 1; evaluation of mean defect (MD) with static perimetry
HFA showed that 53% of HBO patients had 80% of residual mean sensitivity
compared to 23.5% of the control group patients (X(2) = 4.72; p = 0.035). ERG
b-wave mean values at the end of the protocol were significantly higher in the
HBO treated group (X(2) = 4.53; p = 0.013). CONCLUSION: Our study underlines
that HBO therapy can be a safe alternative approach to RP patients, contributing
to the stabilization of their visual function concerning visual acuity, visual
field, and ERG responses while waiting for a definite cure.
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Exp Eye Res. 2007 Jul;85(1):7-14. Epub 2007 Mar 7.
Long-term visual prognoses in patients with retinitis pigmentosa:
The Ludwig von Sallmann lecture.
Berson EL.
Havard Medical School, Massachusetts Eye and Ear Infirmary, 243 Charles Street,
Boston, MA 02114, USA.
Retinitis pigmentosa can be followed over almost its entire course with narrow
bandpassed, computer averaged cone electroretinograms (ERGs). The long-term rate
of decline of these responses can be described by an exponential function. A
cone ERG actuarial table based on 1039 patients and 6553 visits is presented to
show the estimated number of years for an average patient with a given 30-Hz
cone ERG amplitude to decline to 0.05muV (i.e. virtual blindness). The table is
based on a projected rate of loss of 10% of remaining cone ERG amplitude per
year for those not on treatment and 8.3% per year for those on treatment with
vitamin A palmitate 15,000IU/day. The table can be used to provide an estimate
of the average long-term visual prognosis from a single visit; more precise
estimates for a specific patient require several additional visits over 2- to
3-year intervals. Evidence is presented to support the idea that patients with a
projected cone amplitude of 3.5muV or greater at age 40 (about 25% of our
patient population with typical retinitis pigmentosa) would be expected, on
average, to retain some useful vision for their entire lives without treatment.
Knowledge of the amount of remaining cone function in the ERG often reduces
patient anxiety and helps patients plan for their future.
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Arch Ophthalmol. 2007 Jun;125(6):759-64.
Treatment of cystoid macular edema in retinitis pigmentosa with
intravitreal triamcinolone.
Scorolli L, Morara M, Meduri A, Reggiani LB, Ferreri G, Scalinci SZ, Meduri RA.
Department of Pathophysiological Optics, University of Bologna, Via Zuccardi
Merli 1, 40141 Bologna, Italy. luciascorolli@yahoo.it
OBJECTIVE: To evaluate the results of treatment with intravitreal triamcinolone
acetonide injection in patients with cystoid macular edema secondary to
retinitis pigmentosa. METHODS: This prospective, nonrandomized comparative trial
included 20 eyes of 20 patients with cystoid macular edema secondary to
retinitis pigmentosa (group A) and 20 eyes of 20 control individuals (group B)
with the same characteristics who declined treatment. All treated eyes received
an intravitreal injection of 0.1 mL of triamcinolone acetonide (4 mg). The total
follow-up was 12 months. The main outcome measures were best-corrected visual
acuity, central macular thickness measured by optical coherence tomography, and
intraocular pressure. RESULTS: No statistically significant changes were
observed in best-corrected visual acuity. Central macular thickness showed
statistical differences between the 2 groups. Intraocular pressure showed a
statistically significant increase after the first day, at 1 month, and at 3
months in both groups but no significant increase afterward. CONCLUSIONS:
Intravitreal triamcinolone administration may be useful for select cases of
cystoid macular edema in patients with retinitis pigmentosa but its efficacy
seems to be limited over time. Therefore, to obtain a good anatomical result and
an improvement of best-corrected visual acuity, further treatment would be
necessary after 6 months.
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J Neural Eng. 2007 Jun;4(2):R14-31. Epub 2007 Mar 14.
Prosthetic interfaces with the visual system: biological issues.
Cohen ED.
Division of Physics, Office of Science and Engineering Labs, Center for Devices
and Radiological Health, HFZ130, 12725 Twinbrook Pkwy. Rockville, MD 20852, USA.
The design of effective visual prostheses for the blind represents a challenge
for biomedical engineers and neuroscientists. Significant progress has been made
in the miniaturization and processing power of prosthesis electronics; however
development lags in the design and construction of effective machine-brain
interfaces with visual system neurons. This review summarizes what has been
learned about stimulating neurons in the human and primate retina, lateral
geniculate nucleus and visual cortex. Each level of the visual system presents
unique challenges for neural interface design. Blind patients with the retinal
degenerative disease retinitis pigmentosa (RP) are a common population in
clinical trials of visual prostheses. The visual performance abilities of
normals and RP patients are compared. To generate pattern vision in blind
patients, the visual prosthetic interface must effectively stimulate the
retinotopically organized neurons in the central visual field to elicit
patterned visual percepts. The development of more biologically compatible
methods of stimulating visual system neurons is critical to the development of
finer spatial percepts. Prosthesis electrode arrays need to adapt to different
optimal stimulus locations, stimulus patterns, and patient disease states.
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Br J Ophthalmol. 2007 Jan 10; [Epub ahead of print]
Continued Use of Dorzolamide for the Treatment of Cystoid Macular
Edema in Patients with Retinitis Pigmentosa.
Fishman GA, Apushkin M.
University of Illinois Eye and Ear Infirmary, United States.
AIMS: To determine the value of a topical carbonic anhydrase inhibitor for
extended treatment of cystoid macular edema (CME) in patients with retinitis
pigmentosa (RP). METHODS: Eight patients with RP and foveal cystic-appearing
lesions observed on fundus examination and by optical coherence tomography (OCT)
testing were treated with a topical form of carbonic anhydrase inhibitor.
RESULTS: Foveal cystic-like spaces were documented by OCT testing in all eight
patients prior to treatment. All patients showed a significant reduction in
their foveal thickness (FT) and foveal zone thickness (FZT) in at least one eye
after using 2% dorzolamide three times a day for 1 or 2 months. Six patients
demonstrated an improvement in both eyes. After an additional 6 to 13 months of
the same treatment regimen, of six patients who showed a sustained reduction in
FT and FZT in at least one eye, four demonstrated this reduction in both eyes.
While they still remained on Trusopt, a recurrence (rebound) of CME in both eyes
was observed in two patients while one patient showed a sustained improvement in
one eye and rebound of CME in the other eye. Out of 8 patients, 3 showed an
improvement of their visual acuity by 7 letters or more, in at least one eye, on
Snellen acuity charts which was determined as clinically significant.
CONCLUSION: Results from our study suggest that RP patients could potentially
sustain a beneficial effect from continued treatment with a topical form of
carbonic anhydrase inhibitor.
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Br J Ophthalmol. 2007 Jan 10; [Epub ahead of print]
Continued Use of Dorzolamide for the Treatment of Cystoid Macular
Edema in Patients with Retinitis Pigmentosa.
Fishman GA, Apushkin M.
University of Illinois Eye and Ear Infirmary, United States.
AIMS: To determine the value of a topical carbonic anhydrase inhibitor for
extended treatment of cystoid macular edema (CME) in patients with retinitis
pigmentosa (RP). METHODS: Eight patients with RP and foveal cystic-appearing
lesions observed on fundus examination and by optical coherence tomography (OCT)
testing were treated with a topical form of carbonic anhydrase inhibitor.
RESULTS: Foveal cystic-like spaces were documented by OCT testing in all eight
patients prior to treatment. All patients showed a significant reduction in
their foveal thickness (FT) and foveal zone thickness (FZT) in at least one eye
after using 2% dorzolamide three times a day for 1 or 2 months. Six patients
demonstrated an improvement in both eyes. After an additional 6 to 13 months of
the same treatment regimen, of six patients who showed a sustained reduction in
FT and FZT in at least one eye, four demonstrated this reduction in both eyes.
While they still remained on Trusopt, a recurrence (rebound) of CME in both eyes
was observed in two patients while one patient showed a sustained improvement in
one eye and rebound of CME in the other eye. Out of 8 patients, 3 showed an
improvement of their visual acuity by 7 letters or more, in at least one eye, on
Snellen acuity charts which was determined as clinically significant.
CONCLUSION: Results from our study suggest that RP patients could potentially
sustain a beneficial effect from continued treatment with a topical form of
carbonic anhydrase inhibitor.
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Lancet. 2006 Nov 18;368(9549):1795-809.
Retinitis pigmentosa.
Hartong DT, Berson EL, Dryja TP.
Ocular Molecular Genetics Institute, Harvard Medical School, Massachusetts Eye
and Ear Infirmary, 243 Charles Street, Boston, MA 02114, USA.
Hereditary degenerations of the human retina are genetically heterogeneous, with
well over 100 genes implicated so far. This Seminar focuses on the subset of
diseases called retinitis pigmentosa, in which patients typically lose night
vision in adolescence, side vision in young adulthood, and central vision in
later life because of progressive loss of rod and cone photoreceptor cells.
Measures of retinal function, such as the electroretinogram, show that
photoreceptor function is diminished generally many years before symptomic night
blindness, visual-field scotomas, or decreased visual acuity arise. More than 45
genes for retinitis pigmentosa have been identified. These genes account for
only about 60% of all patients; the remainder have defects in as yet
unidentified genes. Findings of controlled trials indicate that nutritional
interventions, including vitamin A palmitate and omega-3-rich fish, slow
progression of disease in many patients. Imminent treatments for retinitis
pigmentosa are greatly anticipated, especially for genetically defined subsets
of patients, because of newly identified genes, growing knowledge of affected
biochemical pathways, and development of animal models.
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Arq Bras Oftalmol. 2006 Sep-Oct;69(5):687-90.
[Visual rehabilitation in patients with retinitis pigmentosa]
[Article in Portuguese]
de Castro CT, Berezovsky A, de Castro DD, Salomao SR.
Setor de Visao Subnormal, Departamento de Oftalmologia, Universidade Federal de
Sao Paulo, Sao Paulo, SP, Brasil. celina@oftalmo.epm.br
PURPOSE: To determine which low-vision aids could be useful to patients with
retinitis pigmentosa and also the benefits that the rehabilitation program could
provide based on visual acuity and/or daily visual tasks. METHODS: A group of 30
patients with retinitis pigmentosa aged from 7 to 73 years were enrolled in this
study. Visual acuity and visual function tests (visual field, full-field
electroretinogram) was performed and low-vision aids tested. Information about
the use of the remaining vision was obtained. After choosing the best optical or
electronic devices and before their prescription, a low-vision training program
was carried out. RESULTS: The best corrected visual acuity varied from HM (hand
movements) to 20/40 for distance and visual acuity better than 16M to 0.5M for
near. 90% of the patients had optical devices prescribed: 13 for near, 9 for
distance, 2 electronic devices and 3 filters. Three patients with extremely
narrow visual field and very low visual acuity were referred to orientation and
mobility. CONCLUSIONS: The low-vision aids were useful for the retinitis
pigmentosa patients: telescopes, hand-held magnifiers, stand magnifiers,
half-eye base-in prism lenses, electronic devices and illumination control were
beneficial to enhance visual acuity and visual efficiency. The prescription of
low-vision aids was helpful in daily-life activities and a high level of
satisfaction with the implemented visual rehabilitation program was reported.
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