RESUMEN
Analysis of vergence troubles is weight by an heavy handicap. In clinical conditions it is easy to value the static vergence balance with a great lot of tests. On the contrary examination of kinetic vergence pattern is generally neglected. Usually a refixation vergence is a combination of an horizontal convergence-divergence of 5 to 10 degrees with a vertical component of 15 to 20 degrees. It is impossible to do their reliable analysis by kinetic EOG because the unequal transmission of potential towards the orbital rim. The authors give the results obtained by photo-oculographic method perfected by Charlier and Buquet. On all recordings it can be noticed that, in vergence refixation, vertical movements of both eyes are always true congruent saccadic versions, while the horizontal movements are disjunctive, dissociated and unequal. On the vertical axis it seems to be no real kinetic vergence at all, but in some cases only a mere tonic alignment. Such a device is a very good mean to study the vergence troubles in daily practice.
Asunto(s)
Movimientos Oculares/fisiología , Oftalmología/métodos , HumanosRESUMEN
The authors present the results of clinical application of a new invasive real time method for ocular movement recording. There is an optical system which measures the gaze direction from the video signals of five reflected corneal dots and pupil image. Their study is based upon 110 simultaneous P.O.G. - E.O.G. recordings of normal beings or patients having various oculomotor troubles. It appears that the heavy odds of such a new method is obvious. It allows to obtain an absolute measurement of eye positions in relation to the basic line whatever the pattern and axis of the moving may be. A quantitative evaluation of all movement parameters is in progress. It still remains to solve the problem of large deviations and the wearing of optical correction during the examination.
Asunto(s)
Electrooculografía , Movimientos Oculares , Oftalmología/instrumentación , Humanos , Procesamiento de Imagen Asistido por Computador , Músculos Oculomotores/fisiopatología , FotograbarRESUMEN
Nowadays, electro-oculography remains the only clinical method for ocular movement recording which is largely used in daily practise, but it has many drawbacks and limits. Till now the photo-oculographic technics have been only applied in laboratory conditions. A new differential photo-oculographic procedure is presented. This optical method is based upon the measurement of gaze direction and ocular movement amplitude from the relative pattern of five reflected corneal dots and pupil image which are located in two different optical plans. The authors relate in detail the recording devices and processing materials for the computerized analysis of video signals. The preliminary results confirm the real advantages of the method which allows to record all sorts of ocular movements in clinical conditions.
Asunto(s)
Movimientos Oculares , Procesamiento de Imagen Asistido por Computador , Humanos , MicrocomputadoresRESUMEN
Up to now EOG has been the only method used to record ocular movements in daily practice. However such a mean has various drawbacks and limits. It has two main gaps: firstly for vertical movements because the interference discharges related with palpebral movements and blinkings; on the other hand for oblique movements because the unequal transmission of EOG potential towards the orbital rim. The differential photo-oculography perfected by Charlier et Buquet has been fitted and now can be easily used in clinical conditions. With this optical method, it exists a direct relation between the gaze direction and video signals of the eye. The authors point out the reliability of its results not only for horizontal movements, but also for vertical and oblique movements. This method allows a relevant analysis of all kinetic parameters whatever the moving axis may be.
Asunto(s)
Movimientos Oculares/fisiología , Trastornos de la Motilidad Ocular/fisiopatología , Oftalmología/métodos , Humanos , Oftalmología/instrumentaciónRESUMEN
Exotropias secondary to convergent squint surgery are fully different from primary exotropias. Their frequency appears to be largely variable according to the operative procedures. The computerized analysis of 160 consecutive exotropias reveals the compound nature of their motor impairments. In each case it is necessary to carry out a careful check up of various causal parameters, but the authors find they are not bound by simple correlations. In all cases an elongation reducing one or several muscles is noticed. Such anomalies are much more frequent and heavy than those observed in primary esotropias. Their iatrogenic origin is unquestionable. In 37% of the cases heavy capsular scars have been observed; their consequences on passive forces are obvious, but it is difficult to carry out their exact evaluation by the usual clinical tests. In that series the resulting surgical planning was made according to the various abnormal parameters had allowed the achievement of a good motor result in 89% of the cases. In 86% of the cases, only one additional operative procedure was necessary.