Visual impairment rehabilitation
The rehabilitation of visual disorders is a part of orthoptics . Orthoptists , rehabilitation specialists and other therapeutic professions such as occupational therapy are active both in the rehabilitation of the visually impaired (low vision) and in the rehabilitation of patients with neurogenic visual disorders (e.g. after a stroke or after an accident). Orthopedic rehabilitation tries to minimize visual and perception deficits, to develop strategies to compensate for them and to train learned processes in everyday life. Computer-assisted rehabilitation methods are also being used more and more frequently.
Rehabilitation at low vision
In fulminant diseases of the eye, such as B. macular degeneration , retinal changes , optic nerve shrinkage , clouding of the lens , cornea or vitreous humor , pigment disorders, color blindness and eye tremors ( nystagmus ), therapy in the context of rehabilitation is primarily carried out by fitting suitable magnifying visual aids ( glasses , contact lenses , edge filter glasses ). Monoculars , handheld magnifiers , magnifying glasses , illuminated magnifiers, screen reading systems and electronic magnifying glasses are other aids that are used in the context of care.
As a result of the increasing spread of EDP applications, visual aids are also in demand in the computer sector. The only computer-aided applications in this area are image detail-enlarging applications and electronic reading aids ( screen readers ), as they are often found in standard software.
Rehabilitation of central vision disorders
According to the orthoptics catalog of indications, the central visual disorders are divided into three sub-areas:
- Cerebral vision disorders after acquired brain damage
- Visual disturbances in retinal dysfunction
- Visual disturbances in demyelinating diseases
Cerebral vision disorders
After traumatic brain injuries (TBI), brain tumors or after their surgical removal, after cerebral infarction, cerebral haemorrhage or oxygen deficiency (cerebral hypoxia), the visual center in the brain may also be affected - visual disturbances with different symptoms are the result.
Reduced visual acuity, double vision, color impairment, impairment of reading ability, visual field loss, visual field defects and much more. can occur.
In addition to the conventional forms of therapy, as we have already got to know in low vision therapy, vision training is also used here in rehabilitation. This serves to practice visual application strategies, as well as to maintain, but also to regain reading skills. Improvements can be achieved here through visual activation and also through the use of computer-aided writing, reading and hemianopia training.
Retinal dysfunction
In macular degeneration (especially age-related) and retinopathy (vascular changes, bleeding in the eye, e.g. as a result of hypertension and diabetes), around 30% of blindness in the western hemisphere can be traced back to this, and symptoms often similar to those in cerebral visual disturbances . In this area mainly conventional therapy methods (optical aids) are used.
Demyelinating diseases
In the case of visual disturbances due to demyelinating diseases (e.g. multiple sclerosis), the therapy primarily offers the use of optical aids that are intended to alleviate the symptoms (similar to the other two diseases).
Rehabilitation of brain-damaged patients with cerebral vision disorders
The most common visual disturbance after brain damage is homonymous visual field deficits. Visual orientation and reading ability are considerably reduced.
Homonymous visual field defects pose two main problems:
Hemianope reading disorder
- Patients with this reading disorder skip lines, leave out parts of a line, read slowly or only briefly and their reading time is short.
- In order to improve reading techniques, exercises to facilitate interlacing, reading numbers and searching for passages of text are carried out.
- The next step is reading training in which word lengths, the position of the words on the screen, the number of words and the length of time the words appear on the screen vary. In addition, the level of difficulty of the text is increased.
- Finally, attempts are made to make it easier for the patient to read books and magazines and to write texts on the computer. The aim is also to continuously increase the reading time.
Visual exploration disorder
- Everyday problems such as overlooking people, obstacles, etc. and thereby bumping into them, as well as orientation problems in groups of people and in squares, make the patient of a visual exploration disorder to create. The patient's eye movements in the blind area are reduced, disorganized, and the number of movements is too few.
- By training saccadic eye movements in the blind half-field, the field of vision is enlarged and the speed of the search movement and detection increased. Saccades are the quick and jerky movements with which the eye is consciously moved from one fixation point to the next.
- By systematizing the visual search in space, this helps the patient to better spatial orientation and to increase the search rate.
- Ultimately, the visual field training should enable the patient to do some things that are relevant to everyday life at least better than before (e.g. orientation in buildings and city districts, running errands and the associated processes such as using public transport and crossing streets, finding their way around even in unfamiliar surroundings) .
In addition to the problems mentioned, a visual neglect can also occur (mostly on the left), in which the patient seems to have "forgotten" one half of the room. As with the visual exploration disorder, therapy is carried out through saccade training.
Another visual impairment is the fusion disorder. The images that each eye transmits to the brain are not put together, but continue to exist as individual images. The therapy takes place through exercises on the chiroscope or the fusion trainer according to Keller.
Classic exercises
During the exercises it is important to ensure that the head is always straight, because patients with visual exploration disorders in particular automatically move their head to compensate for the missing field of vision and thus to compensate for the blind half field.
A training unit is carried out for around 45 to 60 minutes and that twice a week, a training series comprises around 10 to 15 units, but can also be extended or interrupted due to lack of motivation. In order to ensure the highest possible efficiency, the training is adapted to the patient in terms of rehabilitation progress and skills.
This is where the use of the computer comes in to support rehabilitation.
The exercises mainly take place in the orthoptic academies or rehabilitation stations, but the patients also receive homework in some cases, which are used for further exercise and more frequent training.
Muscle trainer
This type of therapy goes back to Christine Paul and follows the basic principle of making eye movements without moving the head. For this purpose, a ball hung on a string or simply a point to be tracked is moved in such a way that attention is drawn into the blind field of vision. The aim of the training is to be able to perform eye movements in the blind half-field smoothly and consistently.
Saccade training
In this training small and large saccades are trained. In order to enlarge the saccadic search movements into the blind half-field, one practices on the Goldmann perimeter. The patient should fix the middle of a hemisphere with both eyes. Then the patient should use a large saccade to reach a point of light that the orthoptist places at a point in the lost field of vision. The light points are placed one after the other in different places.
During this exercise, a computer can also be used to display the fixation point and the points of light. Depending on the degree of difficulty, the points of light can be more easily displayed systematically with acoustic cues or more difficult. This basically corresponds to the exploration training on the ELEX device (electronically controlled reading and exploration device).
Reading training
Here, too, the therapy takes place on the ELEX device, but in this exercise a single line of text runs across the screen from left to right. The patient's task is to grasp the word in the middle of the screen and read it out loud, whereby the character size, character spacing and walking speed can be changed.
The computer has already been used in some exercises with the ELEX device, but any computer could carry out these exercises with appropriately developed software. It would no longer be necessary to purchase an ELEX device.
Exploration training
In addition to exploration training on the ELEX device, there is also exploration training according to Münßinger / Kerkhoff. Münßinger and Kerkhoff have developed therapy material with a volume of 260 paper templates that can be used for the treatment of visual exploration disorders. It comprises eight task groups with different levels of difficulty. Various geometric figures and shapes are shown on the templates, which must be recognized. Strictly speaking, it is about orientation on the individual templates, because the patient should acquire an economical search and gaze strategy and train to accelerate the search rate. Exercises such as counting and finding figures and shapes as well as comparing objects, depending on the level of difficulty, are carried out in a simple arrangement in columns and rows or in a complex arrangement.
Rehabilitation vision training according to Christine Paul
The basic goal of rehab vision training is to maintain or regain reading skills. By promoting stimuli that affect the sense of touch, e.g. B. through games etc., but also the hand-eye coordination is improved. The training includes exercise documents, which are divided into ten lessons, which are carried out in increasing difficulty. It is important that the patient is neither overwhelmed nor under-challenged; if necessary, lessons can be left out or taken longer. The patient has tasks such as cross-out exercises, crossword puzzles, reading words, connecting numbers, figures to be traced, writing training, word quizzes and search images to solve. Homework and games such as dominoes, memory, and puzzles are useful additions to vision rehab training.
Games
Not only games such as dominoes or memory can be used for rehabilitation, a wide variety of board games are very suitable for use in treatment. These not only offer a change, but also promote the visual recognition of strategies and patterns, the differentiation of small image differences and the overview of situations.
Everyday-oriented therapy measures
Orientation and mobility training
Orientation and mobility specialists develop practical strategies for orientation and mobility in everyday life together with their clients. For example, strategies are practiced on how to move around the city and how to use public transport.
Support from a low vision specialist
Low vision specialists can advise those affected on how the remaining eyesight can be used as effectively as possible through optical aids or special techniques (e.g. eccentric vision).
Support from a specialist in practical life skills
Experts for practical life skills practice strategies for everyday situations with those affected, such as cooking. You can advise those affected on which aids are suitable.
Occupational therapy
The goal of occupational therapy is to achieve the greatest possible independence in everyday life. Together with those affected, it is clarified which aids can help in everyday life. Specific activities such as reading or household chores can be practiced. The occupational therapist supports those affected in finding suitable strategies for these activities. Occupational therapy is particularly suitable for elderly people with visual impairments. You can clarify how the risk of falls can be reduced with the help of the home furnishings and recommend or implement practical measures.
Computer-aided exercises
When using computers in the rehabilitation of visually impaired persons, two different therapeutic approaches are assumed.
Visual restitution therapy
Visual restitution therapy relies on the rebuilding of neuronal complexes by transmitting stimuli to the edge zones of the cerebral defect. With the help of this therapy, such restitutions can be trained on the basis of neuroplasticity . The clinical effectiveness of the therapy has been proven in numerous studies. The data obtained show that about two thirds of the patients have a significant improvement in their vision after six months of training. A study with 24 patients came to the result that the patients could perceive 63 percent of the light stimuli after six months of training - compared to only 54 percent before the start of training. If the training is prolonged, a further improvement in vision can be achieved, which remains stable even after the end of therapy.
Compensation therapy
The second approach for the therapy of the visually impaired with the help of computers is the compensation of the "lost" skills. The attempt is made to compensate for the loss of the visual field through exploration - exploration of the disturbed field of vision - and through saccades - jerky eye movements into the disturbed zone.
literature
- Peter Frommelt, Holger Grötzbach (Ed.): NeuroRehabilitation. Basics, practice, documentation. Blackwell, Berlin et al. 1999, ISBN 3-89412-321-4 .
- Lyviana Hettrich, Bettina Lieb, Christine Paul: "Orthoptics" indication catalog . BOD Professional Association of Orthoptists in Germany V., Nuremberg 2002, ISBN 3-9805367-9-3 .
- Elisabeth Hirmann: Training information for the orthoptic service. Vienna 2004.
- G. Kerkhoff, E. Stögerer, U. Münßinger, G. Eberle-Strauss: Diagnostics of cerebral visual disturbances. EKN Development Group Clinical Neuropsychology, Munich 1991.
- Christine Paul: Vision rehabilitation training. Therapy Guide for Orthoptists. Diagnosis and therapy of cerebral visual disorders after acquired brain damage. Praefcke, Ravensburg 1995, ISBN 3-9801412-1-7 .
- Claudia Pribil: Visual field training at the academy for the orthoptic service. Vienna 1999 (Vienna, Academy for Ortoptics, Diploma thesis, 1999).
- Andreas Schaufler: Low Vision. DOZ-Verlag optical specialist publication, Heidelberg 2011, ISBN 978-3-942873-06-2 .
- Andreas Schaufler: Low Vision. Completely revised new edition. DOZ-Verlag, Heidelberg 2013, ISBN 978-3-942873-14-7 .
- Susanne Traubie-Klosinski: Rehabilitation for homonymous hemiaopia. In: Journal for practical ophthalmology & advanced training in ophthalmology. Vol. 25, 2004, ISSN 0173-2595 , pp. 298-304.
Individual evidence
- ↑ Smallfield, Stacy, Verlag Hans Huber: Elderly people with visual impairments . 1st edition. Bern 2019, ISBN 978-3-456-85781-7 .
