Binocular vision & strabology quarterly, Simms-Romano's最新文献

Purpose: To evaluate and compare the effect of four horizontal rectus muscle Tenotomy And Replacement (TAR) alone and in combination with recessions for strabismus, on visual function and eye movement records in patients with INS without AHP, and to compare these results.

Methods: This was a prospective interventional case series of 14 patients with INS with no AHP or eccentric null point. Patients underwent 4 horizontal eye muscle tenotomy and replacement (TAR) alone or 2 muscle TAR in combination with conventional bilateral horizontal muscle recession according to the presence and type of strabismus. Outcome measures included best corrected visual acuity and nystagmus intensity from eye movement recordings pre and post operatively. Data were compared between patients with strabismus and those without.

Results: Overall nystagmus amplitude and velocity was decreased 28.7% and 21.9% respectively for 4 muscle TAR and 2 muscle TAR with paired strabismus recessions. Visual outcome of combined procedure in patients with INS and strabismus was less comparing with 4 muscle tenotomy. All binocular deviations were surgically corrected and there was no undercorrection or complication. Visual acuity showed improvement in patients who had more impaired pre-operation vision. Most patients were satisfied with cosmetic outcomes.

Conclusions: Tenotomy alone and combined with recession improves both visual function and eye movement records in INS. The procedures show better results in more visually impaired patients. We should consider patients preop VA and their visual potential as prognostic factors for their visual gain. Although visual outcomes are not advanced in all patients, nystagmus dampening effect and cosmetic outcome of these procedures can make them reconstructive options for patients with INS who will not achieve better vision.

Purpose: To compare and repeatedly measure cycloplegic refraction in a cross-section of children using retinoscopy and automated refraction.

Methods: A total of 560 children (corresponding to 1120 eyes) ranging in age from 3 to 10 years participated in the study. Each child underwent a comprehensive eye examination, which included table mounted autorefractor evaluation (Kowa KW-2000) and streak retinoscopy, both after cycloplegia with 1% cyclopentolate hydrochloride. Data were analyzed using Fourier decomposition of the power profile.

Results: More positive values of M component and sphere value were given by cycloplegic autorefraction (AKW) compared with cycloplegic streak retinoscopy (RR). More negative values for the J45 vector and more positive for J0 were given AKW although this difference was not statistically significant.

Conclusions: Our study shows that the table mounted autorefkeratometer Kowa KW- 2000 can be applied to young children with cycloplegia as instrument for cycloplegic refraction, and a discount of +0.67 should be applied on the sphere value. Similar care should be taken on the evaluation of the sphere and spherical equivalent values should be applied in other devices.

Purpose: Near point of convergence (NPC) and near point of accommodation (NPA) were evaluated before and after photorefractive keratectomy (PRK) in normal myopic eyes.

Methods: In this prospective cross sectional study, NPC and NPA were measured in 120 myopic eyes (60 patients) before and 3 months after PRK. Excluding criteria were manifest tropia, previous eye surgery, amblyopia, and any other ocular pathology. All subjects were younger than35 years old.

Results: Fifty-one females (85%) and nine males (15%) participated in the study. The average age of the participants was 25.75 years. Before the operation, the average NPC and NPA were 4.35 cm and 6.9 cm (14.5 D), respectively. NPC and NPA increased significantly 5.63 (p = 0.025) and (p 0.05) to 7.983 cm (12.5 D) (p 0.001), respectively, after 3 months.

Conclusion: NPC and NPA may increase significantly after PRK. Convergence and accommodation problems may affect near visual performance. Therefore, for any PRK candidate, accommodation and convergence should be evaluated.

Purpose: To investigate and report the clinical characteristics at initial presentation in patients who had Duane Syndrome, especially binocular vision and functional amblyopia.

Methods: The medical files of patients with Duane's syndrome were reviewed. The main outcome measures of the study were the initial clinical characteristics including amblyopia and associated risk factors including deficiences of binocular vision.

Results: The review identified 99 patients with Duane Syndrome. The median age of patients was 6 years. The frequency of amblyopia at initial presentation was 23 percent. Forty-five patients had measurable stereopsis and 58 patients had binocular vision fusion.

Conclusions: Amblyopia and altered binocular function are important among the clinical features of Duane Syndrome which should be highlighted at initial examination.

Purpose: We set out to determine the accommodative effects of Atropine on the visual system.

Methods: A prospective study was done on a normal eye in a 31-year-old cooperative adult. One drop of 1% Atropine was instilled and the effect on accommodation, near visual acuity and pupil size was recorded. Accommodation was measured at 1/3 of a meter utilizing the Grand Seiko Auto Refractor. Near visual acuity was measured with the PEDIG ATS 4 near visual acuity test at a set distance of 16 inches.

Results: Atropine caused its greatest effect to accommodation, and to pupil size, 3 hours after installation. Curiously, the greatest effect on near visual acuity was seen 27 hours after instillation at which time it dropped to 20/80. Near visual acuity had improved to 20/25 on day 4. Accommodation returned to normal 8 days after instillation and pupil size returned to normal 12 days after instillation.

Conclusion: One drop of Atropine affected accommodation for 8 days. Despite this, near vision returned to 20/20 by day 5. These findings may impact how Atropine penalization is prescribed to treat amblyopia both to maximize effectiveness and minimize its impact on school performance.

Undiagnosed strabismus may result in serious, life-limiting conditions when undiagnosed and untreated.

Purpose: To evaluate the responsible pathophysiological mechanism in a 15 year old patient with acquired Browns Syndrome presenting with cyclic characteristics.

Methods: In addition to a full orthoptic assessment, magnetic resonance imaging of the orbit, corneal topography and computerized videokeratography data analysis during the diplopic period, during resolution and following betamethasone injection into the trochlear region were accomplished.

Results: The MRI scan demonstrated enlargement of the tendon trochlea complex that was similar during the diplopic episode and resolution. The tendon trochlea complex revealed hyperintensity on T1 weighted sagittal images. At the time of resolution topographic examination revealed steepening of the 55 degree meridian. The patient received an injection of depot betamethasone into the trochlear region. Compared to the period of spontaneous resolution, a steeper 55 degree meridian was demonstrated on corneal topography following steroid injection. The patient was symptom free for more than a year after steroid injection.

Conclusion: The topographical findings and the relief of symptoms after steroid injection suggests a vascular etiology for the condition of Browns Syndrome in this particular case.

Purpose: To show conditions where a vertical deviation, an A- or a V-pattern or cyclotropia can appear after surgery on the horizontal rectus muscles, with or without oblique muscle surgery. Our purpose is also to show conditions when a vertical deviation can be anticipated before horizontal rectus muscle surgery and realignment of the ocular deviation. Finally, our purpose is to stress on some surgical precautions one should take to avoid such complications.

Case reports: We report two cases who showed significant vertical deviations due to complications that followed surgical weakening procedures of the inferior oblique muscles.

Conclusion: 1. Vertical deviations, A and V patterns and cyclotropia can occur, can be anticipated or can be avoided in pure horizontal rectus muscle surgeries 2. Vertical deviations are common following complicated oblique muscles surgery if the surgeon blindly sweeps the muscle hook into the area. They can be avoided if the weakening technique allows direct visualization of the inferior oblique muscle.