scholarly journals Visual Defects Associated with Vigabatrin: A Study of Epileptic Argentine Patients

Author(s):  
María Cecilia Moreno ◽  
Brenda Giagante ◽  
Patricia Saidon ◽  
Silvia Kochen ◽  
Jorge Benozzi ◽  
...  

ABSTRACT:Objective:The aim of the present study was to assess visual alterations in a population of Argentine patients treated with the antiepileptic drug vigabatrin.Methods:Twenty patients receiving vigabatrin and 15 patients receiving carbamazepine were examined with automated perimetry using a Humphrey 120-point full screening strategy. In addition, scotopic flash electroretinograms were performed.Results:Of 20 patients treated with vigabatrin, two were unable to cooperate with testing. Of the remaining 18 patients, all but two showed at least one non-detected point inside the central 40° of the visual field of each eye. Of the 15 carbamazepine-treated patients, three were unable to perform the study. None of the remaining 12 patients showed visual field defects. Both a- and b-wave amplitudes of the scotopic electroretinogram were significantly reduced in 12 patients receiving vigabatrin.Conclusions:Visual field defects among patients on vigabatrin therapy may occur with a higher frequency than previously recognized. The Humphrey 120-points full field screening test and electroretinography are useful tools to assess the visual dysfunction associated with vigabatrin.

Neurology ◽  
1999 ◽  
Vol 53 (5) ◽  
pp. 922-922 ◽  
Author(s):  
R. Kalviainen ◽  
I. Nousiainen ◽  
M. Mantyjarvi ◽  
E. Nikoskelainen ◽  
J. Partanen ◽  
...  

Seizure ◽  
1998 ◽  
Vol 7 (5) ◽  
pp. 422
Author(s):  
J.P. Leach ◽  
P. Rao ◽  
F. Alfat ◽  
G. Kyle ◽  
D.W. Chadwick

2007 ◽  
Vol 16 (1) ◽  
pp. 146-152 ◽  
Author(s):  
Ramanjit Sihota ◽  
Viney Gupta ◽  
Deven Tuli ◽  
Ajay Sharma ◽  
Parul Sony ◽  
...  

Author(s):  
Thomas R. Hedges III

Automated perimetry has changed visual field testing considerably in recent years. What was considered an art has become an exercise in interpreting a set of data points obtained mechanically. Automated perimetry saves ophthalmologists time, which ideally should allow for more visual fields to be obtained on patients with unexplained vision loss. However, one must still keep in mind that automated perimetry still depends on the subjective responses from the patient. More important, automated perimetry has made interpretation of visual field defects, especially those due to occipital lesions, more difficult. For example, macular sparing may not be reflected, especially with programs limited to the central 24° or 30°. A 10° field may be required to show macular sparing. Also, sparing or involvement of the temporal crescent will not be shown with 24° or 30° visual fields. The limitation of most programs may lead to the appearance of incongruity when in fact the field is indeed congruous. Sometimes, a small homonymous hemianopic scotoma will be detected when one eye is tested but will be completely missed when the other eye is tested, giving the false impression that the visual loss is monocular. This is especially problematic if the patient also falsely interprets his or her homonymous loss of vision as monocular. Such individuals may complain of loss of vision in one eye when in fact it is one half of their visual field that is defective. The strategy of automated testing on either side the vertical and horizontal meridians may lead to the false impression that field defects respect the vertical or horizontal meridian when they do not. Automated perimetry should make it possible to test more patients with unexplained vision loss, but all automated visual fields must be interpreted with caution and, when necessary, substantiated with some other method, such as the tangent screen, which remains the most powerful method of detecting the size, shape, and density of visual field defects. Because most ophthalmologists no longer use tangent screen testing, at least an Amlser grid should be used to qualify the nature of a paracentral visual field defect.


2021 ◽  
Vol 6 (1) ◽  
pp. e000429
Author(s):  
Michael Christian Leitner ◽  
Florian Hutzler ◽  
Sarah Schuster ◽  
Lorenzo Vignali ◽  
Patrick Marvan ◽  
...  

ObjectiveSeveral studies report evidence for training-related neuroplasticity in the visual cortex, while other studies suggest that improvements simply reflect inadequate eye fixation control during perimetric prediagnostics and postdiagnostics.Methods and analysisTo improve diagnostics, a new eye-tracking-based methodology for visual field analysis (eye-tracking-based visual field analysis (EFA)) was developed. The EFA is based on static automated perimetry and additionally takes individual eye movements in real time into account and compensates for them. In the present study, an evaluation of the EFA with the help of blind spots of 58 healthy participants and the individual visual field defects of 23 clinical patients is provided. With the help of the EFA, optical coherence tomography, Goldmann perimetry and a Humphrey field analyser, these natural and acquired scotomas were diagnosed and the results were compared accordingly.ResultsThe EFA provides a SE of measurement of 0.38° for the right eye (OD) and 0.50° for the left eye (OS), leading to 0.44° of visual angle for both eyes (OU). Based on participants’ individual results, the EFA provides disattenuated correlation (validity) of 1.00 for both OD and OS. Results from patients suffering from cortical lesions and glaucoma further indicate that the EFA is capable of diagnosing acquired scotoma validly and is applicable for clinical use.ConclusionOutcomes indicate that the EFA is highly reliable and precise in diagnosing individual shape and location of scotoma and capable of recording changes of visual field defects (after intervention) with unprecedented precision. Test duration is comparable to established instruments and due to the high customisability of the EFA, assessment duration can be shortened by adapting the diagnostic procedure to the patients’ individual visual field characteristics. Therefore, the saccade-compensating methodology enables researchers and healthcare professionals to rule out eye movements as a source of inaccuracies in pre-, post-, and follow-up assessments.


2021 ◽  
Vol 15 ◽  
Author(s):  
Rijul Saurabh Soans ◽  
Remco J. Renken ◽  
James John ◽  
Amit Bhongade ◽  
Dharam Raj ◽  
...  

Standard automated perimetry (SAP) is the gold standard for evaluating the presence of visual field defects (VFDs). Nevertheless, it has requirements such as prolonged attention, stable fixation, and a need for a motor response that limit application in various patient groups. Therefore, a novel approach using eye movements (EMs) – as a complementary technique to SAP – was developed and tested in clinical settings by our group. However, the original method uses a screen-based eye-tracker which still requires participants to keep their chin and head stable. Virtual reality (VR) has shown much promise in ophthalmic diagnostics – especially in terms of freedom of head movement and precise control over experimental settings, besides being portable. In this study, we set out to see if patients can be screened for VFDs based on their EM in a VR-based framework and if they are comparable to the screen-based eyetracker. Moreover, we wanted to know if this framework can provide an effective and enjoyable user experience (UX) compared to our previous approach and the conventional SAP. Therefore, we first modified our method and implemented it on a VR head-mounted device with built-in eye tracking. Subsequently, 15 controls naïve to SAP, 15 patients with a neuro-ophthalmological disorder, and 15 glaucoma patients performed three tasks in a counterbalanced manner: (1) a visual tracking task on the VR headset while their EM was recorded, (2) the preceding tracking task but on a conventional screen-based eye tracker, and (3) SAP. We then quantified the spatio-temporal properties (STP) of the EM of each group using a cross-correlogram analysis. Finally, we evaluated the human–computer interaction (HCI) aspects of the participants in the three methods using a user-experience questionnaire. We find that: (1) the VR framework can distinguish the participants according to their oculomotor characteristics; (2) the STP of the VR framework are similar to those from the screen-based eye tracker; and (3) participants from all the groups found the VR-screening test to be the most attractive. Thus, we conclude that the EM-based approach implemented in VR can be a user-friendly and portable companion to complement existing perimetric techniques in ophthalmic clinics.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Fiona J. Rowe ◽  
Carmel Noonan ◽  
Melanie Manuel

Aim. To compare semikinetic perimetry (SKP) on Octopus 900 perimetry to a peripheral static programme with Humphrey automated perimetry. Methods. Prospective cross-section study comparing Humphrey full field (FF) 120 two zone programme to a screening protocol for SKP on Octopus perimetry. Results were independently graded for presence/absence of field defect plus type and location of defect. Results. 64 patients (113 eyes) underwent dual perimetry assessment. Mean duration of assessment for SKP was 4.54 minutes ±0.18 and for FF120 (). 80% of results were correctly matched for normal or abnormal visual fields using the I4e target versus FF120, and 73.5% were correctly matched using the I2e target versus FF120. When comparing Octopus results with combined I4e and I2e isopters to the FF120 result, a match for normal or abnormal fields was recorded in 87%. Conclusions. Humphrey perimetry test duration was generally longer than Octopus SKP. In the absence of kinetic perimetry, peripheral static suprathreshold programme options such as FF120 may be useful for detection of visual field defects. However, statokinetic dissociation may occur. Octopus SKP utilising both I4e and I2e targets provides detailed information of both the defect depth and size and may provide a more representative view of the actual visual field defect.


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