[Morphoscopic perception at variable contrast and luminance levels in 97 subjects]. / Le sens morphoscopique à contraste et luminance variables chez 97 appelés du contingent.

BACKGROUND: Morphoscopic perception at variable contrast and luminance levels has been assessed in various diseases and in occupational medicine. To our knowledge, this function has not been studied in young adults of similar age. We performed a prospective study to assess morphoscopic perception at variable contrast and luminance levels in a group of young servicemen. METHODS: A total of 97 subjects (194 eyes) with a mean age of 22.4 (standard deviation 1.16) years were assessed with the Gradual monitor. After visual acuity was measured, morphoscopic perception was assessed at a mean light level of 85 cd/m2, at low, medium and high spatial frequencies, with myopic correction. All subjects whose visual acuity was not correctable to 10/10 in both eyes or whose score was statistically too different from the mean underwent a complete ophthalmologic examination. RESULTS: Overall, 87 subjects had a visual acuity correctable to 10/10 or better in both eyes. For 34 of the 87, at least one of the six scores was more than 1 standard deviation below the mean; however, for 16 subjects the result was within normal limits after minor adjustment of the correction, often of a small degree of astigmatism. Of the 18 remaining subjects 7 had microstrabismus, 8 had anatomic lesions and 3 had lesions of unknown origin. Of the 13 subjects with a visual acuity of less than 10/10, 5 had relative amblyopia, 2 had major ametropia, 2 had unilateral and 2 bilateral ophthalmologic lesions, and 2 had reduced acuity of unknown cause. INTERPRETATION: In this young population the most frequent cause of reduced contrast sensitivity (40%) was associated with minor uncorrected or badly corrected refractive problems. The next most frequent cause was problems with binocular vision, with or without amblyopia (11%). In these subjects contrast sensitivity was reduced in the nondominant eye and, in five cases, in the dominant eye also.

[Pseudophakia and aptitude of aviation personnel]. / Pseudophakie et aptitude du personnel navigant.

UNLABELLED: Because of sensorial disruptions, aphakia post-cataract surgery is a cause of unfitness for the job of aeronautics flying personnel. Its correction thanks to intraocular lenses and a correct functional check-up permit to reconsider the fitness through a derogation given by the competent authorities. EQUIPMENT AND METHODS: The authors realized a retrospective study on the 5 last years. 27 flying personnel, 24 to 76 years old, went through a cataract surgery with implantation. The check-up includes a chemical exam completed by a morphoscopic, coloured and spatial study. RESULTS AND DISCUSSION: The files are more or less well-documented according to their origin. The flying personnel have an average of 4,010 flying hours. The average post-operative hindsight is 30 months. 3 wear intraocular lenses of rear chamber among which 1 is multifocal. 7 were examinated at the CPEMPN with satisfying morphoscopic, coloured and luminous sense compatible with the fitness. 4 are declared permanent unfit (1 professional pilot with bad results, 1 private pilot with other pathologies, 1 inexperienced stewardess getting through the admission visit with insufficient post-operative hindsight, 1 professional pilot declared unfit for its military activity in the reserve). 4 are qualified with restriction. 20 are qualified without restriction. CONCLUSION: The correction of aphakia with intraocular lenses permits in most cases to obtain good functional results compatible with the flying aptitude.

[Personnel with poor vision at fighter pilot school]. / Des malvoyants à l'école des pilotes de chasse.

The piloting of fighting aircraft, the navigation of space-shuttle, the piloting of an helicopter in tactical flight at an altitude of 50 metres require the use of all sensorial, ocular, vestibular, proprioceptive ... sensors. So, the selection and the follow-up of these aerial engines' pilots need a very complete study of medical parameters, in particular sensorial and notably visual system. The doctors and the expert researchers in Aeronautical and spatial Medicine of the Army Health Department, which have in charge the medical supervision of flight crew, should study, create, and improve tests of visual sensorial exploration developed from fundamental and applied research. These authenticated tests with military pilots were applied in ophthalmology for the estimation of normal and deficient vision. A proposition to change norms of World Health Organisation applied to the vision has been following these to low visual persons was equally introduced.

[Multifocal implants of 3 optic zones: optical performance and clinical functional results]. / Implants multifocaux à trois zones optiques: performances optiques et résultats fonctionnels en clinique.

PURPOSE: Evaluation of multifocal IOL (three optical zones). METHODS: Twenty patients were implanted. Main outcome measures were: uncorrected and best corrected distance and near acuity, brigthness acuity test, contrast acuity with differents methods: Pelli-Robson Chart, Gradual System, and spatial visual integration (SVI). RESULTS: Uncorrected visual acuity was restored in 94% of cases. Contrast sensitivity was preserved with the Pelli-Robson chart test but a loss of contrast sensitivity was found with the multifocal IOL with the Gradual system and the SVI in comparison with monofocal IOL. CONCLUSION: Multifocal IOL (three optical zones) allows a good restoration of both near and far visual acuity but a decrease in contrast sensitivity was detected.

[Contrast sensitivity in navigating seamen]. / Sensibilité aux contrastes et conduite des navires.

UNLABELLED: Visual acuity measurement is the ophthalmological test used for determining the majority of professional aptitude thresholds. In the case of ship pilotage however, the necessity to detect physical information of size and variable contrast can only be partly assessed by this parameter. AIMS OF THE STUDY: A test considered to be more ergonomic for the visual capacity evaluation of seamen, and for the early diagnosis of ocular abnormalities, was evaluated. METHOD: At the time of their statutory aptitude visit, 159 professional seamen underwent a test for morphoscopic sense at variable contrast and luminance, gradual. RESULTS: Twenty-seven ametropias of -0.75 to +3.00 diopters, 2 hypertensive retinopathies and 2 optical neuropathies were detected. Despite their low visual acuity, the myopic subjects were able to preserve normal visual efficiency in low contrast, without correction. Inversely, in spite of the correction, a deficiency was noted at medium and low contrasts, with a special increase at low luminance. The 7 patients operated on for radial keratotomy, although their visual acuity reached 10/10, presented a morphoscopic discrimination deficiency at low and medium contrasts. CONCLUSION: The test used in this study is designed for morphoscopic discrimination testing in which contrast and luminance are variable. This determination of luminance contrast sensibility seems to be an informative, sensitive and reliable means of detecting uncorrected ametropia and diverse organic pathologies at their inset.

[Refractive disorders. Clinical aspects and spontaneous course]. / Troubles de la réfraction. Clinique et évolution spontanée.

Refraction is the name given to determination of the dioptric values of the eyes, which is indispensable to correct the visual deficit due to ametropia. Disorders of refraction affect half the world population, and for this reason much attention should be paid to their diagnosis and treatment. Their various symptoms result in nuisances at school age and in the exercise of most professions, thereby preventing the subjects affected from enjoying a full life. Measuring refraction is a basic examination for all ophthalmologists.

Aircrew fitness decisions and advances in refractive surgery techniques.

Refractive surgery is a well mastered technique for the correction of ametropia. The results in terms of recovery of visual acuity are generally very satisfactory. However, when patients are applicants for pilot training it is necessary to consider the structural effects of the operation and its repercussions on the visual function. Since 1981, we have examined 273 eyes of subjects applying to flight crew. The alterations, in the corneal structure, in the sensitivity to contrasts, and in the resistance to glare have dampened the former enthusiasm of the operated. We have evaluated the functional and clinical consequences of each individual case as well as the administrative decisions made concerning these applicants. The outcome is that on average one of three applicants obtained a dispensation within a time limit ranging from 1 to 5 years after surgery, according to the field applied for.

Effect of a dopaminergic agonist, piribedil (Trivastal 50 mg LP), on visual and spatial integration in elderly subjects.

Dopamine acts as a neuromodulator in the retina. Dopaminergic deficiency of any origin, as observed in elderly subjects, is associated with altered visual performances, and more specifically with altered perception of contrasts. The goal of this study was to compare contrast vision in elderly subjects and young subjects (first phase, n = 20), then to compare this function in elderly subjects before and after 3 months of treatment with a dopaminergic agonist, piribedil (Trivastal 50 mg LP), administered once daily (second phase, n = 20). The perception of contrast was analysed using a test measuring sensitivity to colour contrast yielding threshold values for sensitivity to contrast in eight spatial frequencies and three colours (red, green, blue) and in two directions (horizontal and vertical). The results of the first phase of the study demonstrated that elderly subjects showed a decrease in contrast perception in comparison with young subjects, primarily in the high frequency range, and over the full range of stimulation for direction and colour. In the second phase, elderly subjects, in comparison with young subjects, showed altered visual contrast, again in the high frequency range, but also in the low frequency range for horizontal simulation with red and blue. After 3 months of treatment with piribedil the mean contrast sensitivity threshold, over the entire frequency range, had significantly increased (P less than 0.05) for all stimulations, apart for red in the vertical direction. These results underline the value of treatment with a dopaminergic agonist, piribedil in visual disturbances in patients with dopaminergic deficiency (Parkinson patients or elderly subjects).

A family with acquired and inherited blue-yellow axis.

The pedigree of a family with a blue-yellow axis in the Farnsworth 100-Hue is reported. The fact that a blue-yellow axis corresponds to an inherited defect in 6 subjects and to an acquired defect in 1 subject is discussed. Methodological conditions necessary for making the differential diagnosis between an inherited and an acquired blue-yellow defect are recalled.

[A new simple instrument for ophthalmologic evaluation of patients with "low vision"]. / Nouveau matériel simple pour l'évaluation par l'ophthalmologiste d'un patient atteint de "basse vision".

Authors present specially adapted visual acuity charts for "low vision" patients. For them refraction must be surveyed as often as possible.

[Visual handicap, autonomy and third party compensation. Evaluation trials]. / Handicap visuel, autonomie et tierce personne. Essais d'évaluation.

Nowadays visual disability compensation, as for other disabilities, is mainly contingent on the patient's obtaining an allowance for a third party, but this is increasingly related to the concept of autonomy in the main activities of everyday life. This concept cannot be applied to visual handicaps. A special allowance, however, which need not be identical to that of third party compensation but would cover the poor-sighted currently in groups 2 and 3, whatever the extent of their handicap, may be the right solution for the Authorities to adopt, due to the specific nature of the visual handicap.

[Contrast sensitivity function. Results of an epidemiologic study]. / De la valeur de la fonction de sensibilité au contraste. Résultats d'une étude épidémiologique.

The examination of contrast sensitive function partially tests the capabilities of ganglion cells. However, this method has not yet proven to be an unquestionable way of diagnosis, 108 Subjects with various pathological conditions were tested with this technique in order to confirm its value for ophthalmological pathology. The first epidemiological results show that there are changes in curves obtained for clinically sick patients, and that the currently used equipment is most sensitive of the 4 th frequency and high frequencies. Finally, each colored stimulation is very significant at low frequencies.

[Oculomotor equilibrium and aviation activities]. / Equilibre oculo-moteur et activités aéronautiques.

A good oculomotor equilibrium warrants flight safety. It is indeed directly linked with depth vision an may decompensate, causing a deficit or a diplopia. It is therefore very important to screen pilots carefully and to have periodical examinations to check the oculomotor equilibrium.

[Aids for low vision--strategic approach]. / Les aides à la basse vision--approche stratégique.

There are currently methods to rehabilitate the remaining visual function of visually impaired people. Treatment stages and tests are based on classical physiology of vision and still remain strictly experimental. Recent investigations showed that the visual system, as a whole, operates as a space frequency analyzer. There are reception to each spatial frequency. They have to be assessed with accuracy before any rehabilitation attempting to develop channels which are still functional by elective stimulation. This stimulation must have a maximum determined energetic efficiency. The study of the Fourier spectrum on two different images demonstrates this possibility and starts opening the way for specific research.

[A case of MEWDS. "The multiple evanescent white-dot syndrome"]. / A propos d'un cas de MEWDS. "Syndrome des taches blanches rétiniennes fugaces".

A young white man developed acute bilateral visual loss with no previous general illness. Ophthalmoscopic examination showed multiple small yellow-white lesions scattered throughout the posterior poles and mild periphery fundus. There was also fine granularity of two foveal areas and one optic disc margin was blurred. Fluorescein angiography showed early hyperfluorescence of the lesions and late staining of the retinal pigment epithelium. Electrophysiologic abnormalities were transient, asymmetric, more marked in photopic than in scotopic. The origin could be in retinal bipolar cells. These lesions regressed, with return of normal visual function within several weeks. These clinical findings are different from others acute inflammatory diseases primarily involving retinal pigment epithelium and photoreceptors. This aspect is usually described as "multiple evanescent white dot syndrome". The etiology of this syndrome remains unknown with no evidence of systemic disease. A history of flulike illness is rare.