Strabismus Precipitated by Monovision

Optometry and Vision Science, 2013

Purpose. To describe our experience with monovision excimer laser correction in individuals with myopic presbyopia. Methods. This prospective interventional case series was conducted in a private refractive surgery center on 40 patients with presbyopia aged 40 years and older, who were treated with monovision refractive surgery between 2010 and 2011. The dominant eye was corrected for distance vision and the nondominant eye was corrected for near vision, with anisometropia of Q1.00 diopters (D). All patients underwent comprehensive objective and subjective visual assessments, including a questionnaire that was filled out preoperatively and at 6 and 12 months postoperatively. The primary outcomes were preoperative and postoperative refraction, binocular visual acuity, stereopsis, contrast sensitivity, glare, and questionnaire results. Results. The 1-year follow-up was completed by 38 patients (95%). Preoperative and 1-year postoperative refraction of the distance eye spherical equivalent (SE), anisometropia SE, and uncorrected visual acuity were j4.05 T 1.94 and j0.01 T 0.22 D, 0.45 T 0.50 and 1.73 T 0.56 D, and 0.87 T 0.2 and 0.09 T 0.11 logMAR, respectively. Best-corrected visual acuity was unchanged. Both mean distance and near stereopsis decreased, from 52 to 142 seconds of arc and from 54 to 57 seconds of arc, respectively. Contrast sensitivity and glare decreased significantly. Patient satisfaction improved from 41.5 T 30.4% to 85.2 T 5.0% (range, 40 to 100%) at the 1-year follow-up. Conclusions. Monovision excimer laser correction provides both effective and satisfactory results and should be considered as an option for individuals with myopic presbyopia suitable for, and interested in, refractive surgery.

Case Reports in Ophthalmology

Post-surgical or traumatic corectopia is among the rare causes of monocular diplopia. A 26-years-old student presented to the Institute with a complaint of monocular double vision in the left eye. He had a penetrating ocular injury in the left eye and subsequently, undergone for multiple ocular surgeries. Following the final intraocular lens implantation, he experienced a monocular double vision in his left eye. Upon contact lens clinic presentation, visual acuities were 20/20 in the right and 20/320 in the left eye (improved to 20/25 with pinhole). Slit-lamp examination on the left eye revealed scarring in the superior nasal quadrant of the cornea, irregular mid-dilated pupil with exposed aphakic and pseudophakic portions. A range of different optical management options were implemented to eliminate monocular diplopia and to correct refractive error. Finally, a combination of prosthetic soft contact lens and spectacle correction was able to remove diplopia and provide binocular sin...

Transactions of the American Ophthalmological Society, 2006

To evaluate the effects of three increasing powers of monovision contact lenses on both objective and subjective vision in emmetropic presbyopic patients. A prospective single-center study was conducted on 50 emmetropic presbyopic patients with a mean age of 55.4 +/- 4.3 years (range, 50 to 66). Each patient wore for 1 week a +0.75 D, +1.50 D, and +2.50 D contact lens in the nondominant eye. Objective testing after each week included near and distance visual acuity, distance stereopsis, distance contrast sensitivity, and measurement with two different aberrometers of spherical equivalent, defocus, spherical aberration, and total higher-order aberrations. Subjective testing included questionnaire responses regarding vision under various conditions after 1 week with each lens power. Statistical tests were performed to determine significant differences from pretreatment. Binocularly, mean uncorrected near visual acuity increased in both eyes (P < .01) with each increase in contact l...

British Journal of Ophthalmology, 2006

Objective: To evaluate the effect of refractive surgery on binocular vision and ocular alignment in patients with manifest or intermittent strabismus, with or without vertical component. Setting: University Hospital Antwerp, Edegem, Belgium. Patients and methods: 13 patients (22 eyes) with strabismus underwent refractive surgery. Five of these patients presented with an esotropia and four of them with a small vertical deviation. Five patients had a manifest exotropia, of whom two presented with a small vertical deviation. Two patients had an intermittent exotropia with binocular vision, of whom one patient had a vertical deviation. One patient had a hypertropia with a dissociated vertical deviation. Results: Ocular alignment and binocular function remained unchanged postoperatively in all except two patients with high anisometropia who experienced an improvement in binocular function. In these patients, the preoperative manifest deviation became intermittent or latent after surgery, allowing fusion and stereopsis. Vertical deviation was found preoperatively in 8 of the 13 patients. This vertical deviation remained unchanged postoperatively, but improved in one patient with anisometropia. Conclusion: Preoperative intermittent or manifest strabismus is not a contraindication for refractive surgery provided some specific recommendations are taken into account, such as an adequate preoperative orthoptic examination and aiming at emmetropia for both eyes.

Graefe's Archive for Clinical and Experimental Ophthalmology, 2012

Background Hemianopia and strabismus leads to severe disturbance of visual orientation and diplopia under binocular conditions if the deviated eye has a normal retinal localization. Subjects and methods Four cases with homonymous (two) and bitemporal (two) hemianopia and strabismus will be described with respect to binocular visual field and diplopia/ confusion. All of them were recommended for strabismus surgery. Preoperatively, prism adaptation test was carried out to analyze functional results and fusional competence. In three of the four cases, strabismus surgery was successfully performed to avoid diplopia/confusion. All three patients revealed normal retinal correspondence. Furthermore, in two cases surgery led to an extension of binocular visual field; in one case with a bitemporal hemianopia and hemifield-slide phenomenon, blurred central vision and reading problems reduced significantly postoperatively. In one patient with anomalous retinal correspondence due to early childhood trauma exotropia led to an extension of the binocular visual field. In this case, strabismus surgery would have been unfavourable. Results Case 1 showed a homonymous hemianopia to the left and acquired exotropia of the right eye, leading to binocular diplopia. Case 2 with homonymous hemianopia to the right and exotropia of right eye revealed anomalous retinal correspondence after history of perinatal brain injury, resulting in absence of diplopia and enlargement of visual field to the right. Cases 3 and 4 with bitemporal hemianopia suffered from sensory disturbances caused by additional acquired strabismus. The exodeviation of the right eye in case 3 led to a restriction of binocular visual field with overlap of the nasal parts causing diplopia, whereas the esodeviation of case 4 resulted in a "gap" between the nasal parts (blind area). Conclusion Depending on the extent of visual field defects and on retinal correspondence, functional consequences for binocular vision and binocular visual field should be considered prior to surgery. In normal retinal correspondence, strabismus surgery will be indicated in most cases because of diplopia. However, surgery might result in a reduction of binocular visual field. Preoperatively, it is important to map monocular and binocular visual fields, to examine retinal correspondence, and to undertake prism adaptation test to imitate the postoperative functional result and risk of double vision.

To determine whether late surgical correction provides fusion in adults who have constant strabismus beginning in early childhood. Materials and Methods: This was a prospective study that included 34 consecutive adults with a history of early onset strabismus who had not previously undergone surgery. They were tested with the Bagolini striated glasses (BSG), Worth four-dot (W4D) test, cover test, and four-prism diopter (4-PD) test, preoperatively, and 6 weeks after surgery. Results: The mean age was 23.8 years, 17 patients had esotropia and 17 patients had exotropia. Preoperatively, all patients demonstrated a manifest horizontal deviation ranging from 30 ∆ to 60 ∆ and had suppression. At 6 weeks postoperatively, 33 patients had a horizontal manifest deviation of <15 ∆ (range, 2 ∆ -14 ∆ ; median, 6 ∆ ), and none were orthotropic as determined by the cover test together with the 4-PD test. All of these 33 patients achieved anomalous retinal correspondence (ARC) with the BSG at near, and 25 (75%) had ARC with the W4D test at near. Conclusions: Although our study has limited number of patients its findings suggest it is possible to develop ARC after surgery in almost all adult patients with childhood-onset strabismus associated with suppression, and who have not previously been operated upon, if satisfactory alignment is achieved in adulthood.

Cureus, 2022

Introduction: The purpose of the present study was to determine the factors that affect the outcome of strabismus surgery in terms of improvement in stereopsis and binocularity. Methods: Data were collected prospectively from patients with childhood-onset, concomitant, constant strabismus greater than 30 prism diopters (PD) with postoperative alignment within 10 PD. Pre- and postoperative stereopsis and binocularity testing were performed using the Titmus fly test, random dot test, Bagolini striated glass test, and Worth four dot test at one, four, and 12 weeks postoperatively. Results: A total of 73 patients (55% males and 45% females) who underwent surgery at our center were studied. The mean age at the time of surgery was 16 ± 7.7 years (range: 5-35 years). We found that factors such as age of strabismus onset, type of deviation, and amblyopia had a statistically significant influence on the postoperative surgical outcome. A statistically insignificant relationship was noted with...

Journal of American Association for Pediatric Ophthalmology and Strabismus, 2003

Introduction: This is the first in a series of articles intended to evaluate the management of strabismus in adults, including clinical outcomes and the quality, cost, and value of treatment from the perspectives of patients and health care providers. Here we present clinical characteristics, complexity of surgery, treatment success, and resolved complaints in a group of adult patients who underwent strabismus surgery. Methods: This is a multicenter retrospective study analyzing the type and amount of ocular misalignment before and after surgery in adult patients with strabismus onset before (BVM, or age Ͻ 9 years) or after (AVM, or age Ն 9 years) visual maturation. Success was evaluated in terms of alignment, motility, and the presence of diplopia; subjective success was measured in terms of resolved complaints. The complexity of surgery was determined using the Intensity/ Complexity Index and compared with success rates. Results: Data are reported on 299 patients (90 BVM and 145 AVM) whose eyes were successfully aligned in 63% of the BVM cases and 81% of the AVM cases. Subjective complaints resolved at similar rates in the BVM and AVM subgroups. Successful alignment was not correlated with complexity of surgery, but motility and sensory success rates were correlated with complexity of surgery. Conclusion: Within each of the BVM and AVM subgroups, this study of adult strabismus showed similar surgical success rates compared with published data. This qualifies these patient groups as clinically typical of adults undergoing strabismus surgery. Additional studies will expand on health value analyses.

Journal of Evidence Based Medicine and Healthcare, 2017

BACKGROUND The gradual decrease in binocularity and stereopsis in patients with concomitant strabismus decreases the depth perception of the patients and adversely affects the reading speed and the motor dexterity skills of the individuals. It had been observed earlier that early management is necessary to help patients regain their binocularity, but recent studies indicate that binocularity and stereopsis may improve in these patients even if they are treated later in life, provided they are managed well. Hence, we undertook this study to determine the extent of improvement in binocularity and stereopsis in patients with long-standing large angle constant concomitant horizontal strabismus after surgical management after the age of 16 years and its association with the postoperative alignment. MATERIALS AND METHODS A prospective clinical trial was conducted in 30 patients with constant concomitant horizontal strabismus of more than 25 prism dioptres who presented after the age of 16 years. Binocularity and stereopsis were measured in the patients with the help of Worth 4-dot test, synoptophore, Lang II test plate, Randot test plates and TNO test plates. The measurements were done preoperatively and 6 weeks after surgical treatment. The changes in the measurements were associated with the postoperative alignment. RESULTS Preoperatively, the patients demonstrated either alternating or unilateral suppression with no measurable stereopsis. Postoperatively, satisfactory surgical alignment defined as tropia less than or equal to 8 Prism Dioptres (PD) was achieved in 23 (76.6%) of the patients. 19 (63.3%) patients achieved binocularity on Worth 4-dot test and synaptophore, but alternating or unilateral suppression was still present in 11 (36.6%) of the patients. 17 (56.6%) of the 30 patients achieved stereopsis on Lang II, Randot and TNO test plates. Development of stereopsis was associated with postoperative alignment with 16 (69.5%) of the 23 satisfactorily aligned patients and only 1 (14.3%) of the 7 patients with a residual deviation of ≥10PD achieving stereopsis. CONCLUSION Significant improvement in binocularity and stereopsis can be achieved in patients with long-standing large angle constant concomitant horizontal strabismus after surgical management even after the age of 16 years and the development of binocularity and stereopsis is associated with the final postoperative alignment.

Scientific Reports

Monovision can be used as a method to correct presbyopia with contact lenses (CL) but its effect on reading behavior is still poorly understood. In this study eye movements (EM) were recorded in fifteen presbyopic participants, naïve to monovision, whilst they read arrays of words, non-words, and text passages to assess whether monovision affected their reading. Three conditions were compared, using daily disposable CLs: baseline (near correction in both eyes), conventional monovision (distance correction in the dominant eye, near correction in the non-dominant eye), and crossed monovision (the reversal of conventional monovision). Behavioral measures (reading speed and accuracy) and EM parameters (single fixation duration, number of fixations, dwell time per item, percentage of regressions, and percentage of skipped items) were analyzed. When reading passages, no differences in behavioral and EM measures were seen in any comparison of the three conditions. The number of fixations and dwell time significantly increased for both monovision and crossed monovision with respect to baseline only with word and non-word arrays. It appears that monovision did not appreciably alter visual processing when reading meaningful texts but some limited stress of the EM pattern was observed only with arrays of unrelated or meaningless items under monovision, which require the reader to have more in-depth controlled visual processing.