Binocular vision & strabismus quarterly最新文献

Purpose: The aim of this study was to determine if patients with strabismic amblyopia could have increased occipital visual cortex activation with monocular stimulation of the sound fixing eye, rather than with simultaneous stimulation of both eyes.

Methods: A prospective study was performed including 12 patients with strabismus and amblyopia, who were evaluated using functional MRI with visual stimulation paradigms. The measurements were made in the occipital visual cortex, assessing the response to the binocular and monocular stimulation.

Results: 12 out of 12 patients showed an increased cortical response of the healthy eye in comparison to the amblyopic one. Nine of the 12 patients showed larger cortical activation with visual stimulation of the healthy eye compared to the binocular condition analysis. Three out of the 12 cases had a greater activation area when the stimulation was binocular rather than monocular, 2 of whom had a relatively small angle of strabismus.

Conclusions: Patients with amblyopia and strabismus could see better with only one eye instead of both eyes. This could be related to inhibition of the binocular function of the brain by the misaligned amblyopic eye.

Purpose: We seek to analyze the results of the innervational surgery in a case of hypotropia with peudoptosis with vidiooculography (3D-VOG).

Case report: We present the clinical case of a 35 year old male suffereing from acquired ptosis of the left eyelid, present since the age of 10 and who was interested in cosmetic surgery. The preoperative 3D-VOG shows hypotropia of the left eye (22.5 degrees), minimum exotropia and intorsion together with limitation in the elevation of the left eye with positive passive duction test and pseudoptosis.

Results: Surgery was carried out in three stages: 1. Recession of the superior rectus of the right eye (RE) resulting in an improvement in the elevation and the pseudoptosis; 2. Recession of the inferior rectus of the left eye (LE), with improvement in the elevation of the LE but deterioration of the pseudoptosis; 3. Resection of the inferior rectus of the RE which improves both the elevation as well as the pseudoptosis of the LE.

Conclusions: We consider the usefulness of the innervational techniques in the incomplete third nerve paralysis with important affectation in the elevation, making it necessary to check and in this case eliminate the restrictive effects although this may influence the effect on the pseudoptosis.

Background: Superior oblique tuck is an effective procedure for the treatment of superior oblique palsy. There has been no report of the extrusion of the non-absorbable suture typically used in this procedure. We describe a case of late extrusion of the non-absorbable suture used in a superior oblique tuck.

Research design: Case report.

Case report: A 4 year old boy underwent a successful left superior oblique tuck for a left superior oblique palsy. Eleven months after surgery, the non-absorbable suture used forf the tuck extruded coincidentally with ocular trauma. The suture was slightly adherent to a suture granuloma in the supranasal quadrant of the left eye and removed without loss of surgical effect of the superior oblique tuck.

Conclusion: Late extrusion of a non-absorbable suture used in a superior oblique tuck may not result in loss of surgical effect. However, this finding does not imply the acceptability of using an absorbable, instead of a non-absorbable, suture in this procedure.

Introduction: Occlusion, pharmacologic pernalization and combined therapy have been documented in controlled studies to effectively treat amblyopia with few complications. However, there remain concerns about the effectiveness and complications when, as in this case, there are not standardized treatment protocols.

Methods: A retrospective chart review of 133 consecutive patients in one community based ophthalmology practice treated for amblyopia was performed. Treatments evaluated were occlusion only, atropine penalization, and combination of occlusion and atropine. Reverse amblyopia was defined as having occured when the visual acuity of the sound eye was 3 LogMar units worse than visual acuity of the amblyopia eye after treatment.

Results: Improvement in vision after 6 months and 1 year of amblyopia therapy was similar among all three groups: 0.26 LogMar lines and 0.30 in the atropine group, 0.32 and 0.34 in the occlusion group, and 0.24 and 0.32 in the combined group. Eight (6%) patients demonstrated reverse amblyopia. The mean age of those who developed reverse amblyopia was 3.5 years, 1.5 years younger than the mean age of the study population, 7/8 had strabismic amblyopia, 6/8 were on daily atropine and had a mean refractive error of +4.77 diopters in the amblyopic eye and +5.06 diopters in the sound eye. Reverse amblyopia did not occur with occlusion only therapy.

Conclusions: In this community based ophthalmology practice, atropine, patching, and combination therapy appear to be equally effective modalities to treat ambyopia. Highly hyperopic patients under 4 years of age with dense, strabismic amblyopia and on daily atropine appeared to be most at risk for development of reverse amblyopia.

Background and purpose: To add to the literature of a case of isolated third nerve paresis involving the nerve fascicles subserving the superior rectus and the levator palpebrae muslces from brain stem infarction and presenting the characteristics of central disruption of binocular vision fusional amplitudes.

Case report: One patient with an old intracranial aneurysm and with old and recent brain stem infarcts and no other neurological manifestations, demonstrating findings characteristic of isolated paresis of the superior rectus and levator palpebrae muscles is reported.

Conclusion: This dual involvement of the superior rectus and levator palpebrae muscles supports the anatomical arrangement of the ocular motor nucleus fascicles in the midbrain, clarified by experimental studies on animals and clinical data in humans and emphasizes the juxtaposition of the superior rectus and levator palpebrae fascicles and placing the levator palpebrae mucle fascicle lateral to the medial rectus fascicle in the midbrain. The comitant vertical deviation and the negative Bielschowsky head tilt test support the vertical rectus muscle involvement. The constant diplopia with only 4 prism diopters of hypotropia and with the absence of fusional amplitudes evokes disruption of central binocular fusion.

Aims: The Bielschowsky Head Tilt Test (BHTT) is a commonly used test in Orthoptic practice and is used mainly to differentiate between a long standing Superior Oblique and Superior Rectus palsy. No consistent test distance is recommended in the literature and therefore the aim of this study was to determine whether test distance had an effect upon the measurements obtained.

Method: Thirteen participants were recruited. Participants had either longstanding or recent onset unilateral Superior Oblique palsy. Prism Cover Test measurements of the vertical angle of deviation were taken whilst the participant tilted their head to either side whilst fixating on a target at 33 cm, 3 m and 6 m.

Results: The test distance does have a significant effect on the change in vertical angle measured with head tilted to either side (x2+7.747,DoF 2, p=0.021). When the median values are considered it appears that the significant effect occurs due to a smaller change in angle between head tilt to the affected side when fixing at 3 metres. This was confirmed using the Wilcoxon signed rank test (33cmv3m p=0.039, 3m v 6m p=0.013 and 33cm v 6m p=0.67).

Conclusions: The testing distance at which the BHTT is performed appears to have an effect upon the measurements obtained. The clinical importance of the difference in the change of angle with head tilt to either side is debatable due to the fact that the difference in the median measurement value between the three test distances is a maximum of 3 prism dioptres.