SEARCH · PubMed Health

Results for “Strabismus”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources

PubMed2005

Final report of the early vs. late infantile strabismus surgery study (ELISSS), a controlled, prospective, multicenter study.

BACKGROUND: The optimal age for surgery for infantile esotropia is controversial. Proponents of early surgery believe that further loss of binocular vision can be prevented by early surgery, a minority believes that binocular vision can even be restored by early surgery. The ELISSS compared early with late surgery in a prospective, controlled, non-randomized, multicenter trial. METHODS: Fifty-eight clinics recruited children aged 6-18 months for the study. Each clinic operated all eligible children either 'early', i.e. at age 6-24 months, or 'late', i.e. at age 32-60 months. At baseline the angle of strabismus, refraction, degree of amblyopia and limitation of abduction were assessed. Intermediate examinations took place every six months. Children were evaluated at age six in the presence of independent observers. Primary endpoints were (i) level of binocular vision, (ii) manifest angle of strabismus at distance and (iii) remaining amblyopia. Secondary endpoints were number of operations, vertical strabismus, angle at near and the influence of surgical technique. RESULTS: A total of 231 children were recruited for early and 301 for late surgery. Age at entry examination was 11.1 months (SD 3.7 months) in the early group and 10.9 (SD 3.7) months in the late group. Refraction, amblyopia and limitation of abduction were distributed equally in the early and late groups, but the angle of strabismus was slightly larger in the early group. Dropout-rates were 26.0% in the early and 22.3% in the late group. At age six, 13.5% of the early vs. 3.9% of the late group recognized the Titmus Housefly; 3.0% of the early and 3.9% of the late group had stereopsis beyond Titmus Housefly. No significant difference was found for angle of strabismus. 35.1% of the early group and 34.8% of the late group did not have an angle between 0 degrees and 10 degrees , the thresholds set for re-operation. For ratio of the visual acuities (remaining amblyopia) there was a small but significant advantage for the early group. There was hardly any correlation between the baseline parameters and the primary endpoints. Children scheduled for early surgery had first been operated at 20 (SD 8.4) months, but 8.2% had not been operated at age six. Children scheduled for late surgery had been operated at 49.1 (SD 12.7) months, but 20.1% had not been operated at age six. The number of operations per child was 1.18 (SD 0.67) in the early and 0.99 (SD 0.64) in the late group. Age at recruitment, age that strabismus reportedly had started and refraction at entry examination were similar among operated and non-operated children. Only the angle of strabismus at entry predicted, to some extent, whether a child had been operated at age six. DISCUSSION: Children operated early had better gross stereopsis at age six as compared to children operated late. They had been operated more frequently, however, and a substantial number of children in both groups had not been operated at all.

Depth Perception↗

PubMed2005

Reasons for delay of surgical intervention in adult strabismus.

BACKGROUND: It has been our impression that adult patients with strabismus frequently delay surgical intervention. OBJECTIVES: To determine the length of time adult patients waited before undergoing strabismus surgery and to determine the reasons why these delays occurred. DESIGN, SETTING, AND PARTICIPANTS: Prospective survey of consecutive patients who delayed strabismus surgery for more than 1 year. INTERVENTION: Preoperative survey. MAIN OUTCOME MEASURES: The primary outcome measure was time between the onset of strabismus and surgery and the reason why surgery had not been previously sought. RESULTS: The mean age among 128 study participants was 45.7 years (age range, 18-86 years). The mean time between the onset of current strabismus and surgery was 19.9 years (range, 1-72 years). The major reasons for delay in seeking surgical treatment included the following: surgery was never offered by eye care specialist (35 patients [27%]), surgery was offered but declined by the patient (29 patients [23%]), the patient had received prior satisfactory nonsurgical care (17 patients [13%]), the patient had never sought care (14 patients [11%]), the patient had a previous poor surgical experience (8 patients [6%]), and the patient had been told by their eye specialist that nothing could be done or that surgery could make them worse (8 patients [6%]). CONCLUSIONS: Strabismus surgery is often delayed for many years in adult patients who could potentially benefit from it. Almost half of such delays could be avoided by better education of the lay public and the medical community.

Adolescent↗

PubMed2006

The Pediatric Vision Screener III: detection of strabismus in children.

OBJECTIVE: To evaluate the clinical performance of the Pediatric Vision Screener (PVS) in children in a pediatric ophthalmology office setting. METHODS: Seventy-seven subjects between 2 and 18 years of age received gold-standard orthoptic examinations and were classified as at risk for amblyopia if strabismus or anisometropia (>1.50 diopters) was present. Strabismus was subclassified as variable or constant. The subjects were then tested with the PVS, which produced a pass or refer recommendation based on a binocularity score. The PVS also produced a yield score to indicate the subject's interest in the target. Sensitivity and specificity for amblyopia risk detection were calculated. RESULTS: Binocularity as determined by the PVS was greater than 65% for all controls and less than 20% for all subjects with constant strabismus. Binocularity ranged from 0% to 52% in subjects with variable strabismus. All subjects with anisometropia and no strabismus had binocularity scores less than 10%. CONCLUSIONS: The PVS identified strabismus, when present, in all subjects and identified 3 subjects with anisometropia as well. The PVS shows potential to address a lack of screening instrumentation appropriate for use with preschool-aged children.

Adolescent↗

PubMed1993

Psychosocial aspects of strabismus study.

OBJECTIVE: To assess the psychosocial implications of growing up with and living with socially noticeable strabismus. DESIGN: Self-report mailed questionnaire and the Hopkins Symptom Checklist. SETTING: Patients with strabismus who were seen at the University of California, Davis, Medical Center, Department of Ophthalmology, from 1976 to 1989. PARTICIPANTS: Forty-three female and male subjects aged 15 years or older who had a history of childhood strabismus that was uncorrected or incompletely corrected past the age of 13 years. INTERVENTION: None. MAIN OUTCOME MEASURES: Participants' responses to our survey and to the Hopkins Symptom Checklist. RESULTS: Strabismus had a negative impact on many aspects of our subjects' lives. They report difficulty with self-image, securing employment, interpersonal relationships, school, work, and sports. Furthermore, difficulties encountered did not go away after childhood, rather, the problems encountered by our subjects intensified in the teenage and adult years. Subjects demonstrated generalized higher levels of distress on the Hopkins Symptom Checklist than age- and sex-matched controls (P < .01). CONCLUSIONS: Psychosocial difficulties relating to socially noticeable strabismus are not just a problem for school-children but also for teenagers and adults. Correction of strabismus in the older teenager or adult may offer them improvement in psychosocial functioning, a benefit not previously reported in the literature.

Adolescent↗

PubMed2005

Psychosocial aspects of mothers of children with strabismus.

PURPOSE: The aim of the study was to investigate the psychological profile of mothers of children with strabismus, their attitudes to their children, and their family functioning. METHODS: This study was conducted at Dokuz Eylül University School of Medicine, from 2000 to 2002 and involved a series of 30 children with strabismus and 31 healthy controls. All mothers were asked to complete Beck Depression Inventory (BDI), State-Trait Anxiety Inventory (STAI), Parental Attitude Research Instrument (PARI), and Family Assessment Device (FAD). RESULTS: Mothers of the children with strabismus had significantly higher depression scores ( P = 0.042) compared with mothers of the control group. They demonstrated significantly lower scores in democratic attitude, meaning that they failed to constitute a supportive and friendship relation with their children, ( P = 0.0001). These mothers had significantly higher scores in rejection of maternal role ( P = 0.017) as compared with mothers of the control group. They were nervous, distressed, and angry in the relationship with their children, with unhappiness and more dissatisfaction with respect to maternal role. Mothers of the children with strabismus had poor role functioning in the family, which is related to satisfying the food, clothing, and support needs ( P = 0.034). They also had poor affective responsiveness, which means the ability of family members to respond with appropriate emotion ( P = 0.003), and poor general functioning ( P = 0.040) as compared with mothers of the control group. CONCLUSIONS: This study demonstrated that, for mothers who have children with strabismus, strabismus had an adverse effect on their lives, and their family relationships.

Adult↗

PubMed2006

Combined strabismus and lens surgery.

BACKGROUND: Simultaneous eye muscle and lens surgery in patients with strabismus and lens abnormalities offers the advantage of avoiding staged surgery. METHODS: Thirty-three combined strabismus and lens surgeries were performed on 30 patients who ranged in age from 22 months to 91 years. Fifteen of the strabismus procedures were performed for esotropia, 12 for exotropia, 4 for vertical deviations, and 2 for combined vertical-horizontal deviations. Surgical amounts often were reduced to lessen the risk of overcorrection, to minimize anesthetic requirements (when using topical rather than general anesthesia), or to avoiding additional surgery on the contralateral or ipsilateral eye. The intraocular surgeries included cataract extraction without or with posterior chamber intraocular lens, secondary intraocular lens implantation, and YAG laser posterior capsulotomy. In 28 cases, muscle and intraocular surgery was performed on the same eye, and in 5 cases the strabismus surgery was performed on the eye opposite the intraocular surgery. RESULTS: The average length of postoperative follow-up was 23.2 months (range, 1-94 months). Surgical, anesthetic, and postoperative complications, other than unsatisfactory ocular alignment, were limited to one retinal detachment in a patient with persistent fetal vasculature. Strabismic undercorrections (>12(Delta) of horizontal deviation or >5(Delta) of vertical deviation) occurred in 11 cases (37%). There were no overcorrections. A poor visual response (<20/50) to the intraocular surgery was encountered in 6 patients, all as the result of amblyopia or preexisting vitreoretinal pathology. CONCLUSIONS: Simultaneous extraocular muscle and lens surgery is an option for patients with strabismus and lens abnormalities. Standard strabismus surgical amounts are recommended.

Adolescent↗

PubMed2005

Severe strabismus after scleral buckling: multiple mechanisms revealed by high-resolution magnetic resonance imaging.

PURPOSE: Strabismus occurring after scleral buckling for retinal detachment typically is attributed to scarring, but this is not the only mechanism. We investigated use of magnetic resonance imaging (MRI) to identify a spectrum of mechanisms of strabismus occurring after scleral buckling. DESIGN: Prospective, noncomparative, observational case series in an academic referral setting. PARTICIPANTS: Six patients with long-standing, large-angle strabismus after monocular or binocular scleral buckling. Horizontal and vertical preoperative deviations, present from 8 to 120 months, ranged from 25 prism diopters to more than 90 prism diopters. METHODS: Multipositional high-resolution MRI of both orbits was performed using surface coils in multiple, controlled gaze positions. Coronal, sagittal, and axial images were obtained as clinically appropriate. MAIN OUTCOME MEASURES: Different mechanisms of pathologic characteristics of the extraocular muscles (EOMs) in complicated strabismus after scleral buckling. RESULTS: Magnetic resonance imaging readily demonstrated EOM size and contractility, as well as features of scleral buckle hardware such as grooves and junctions and relationships of EOMs to the buckle and sclera. Imaging demonstrated that 5 rectus EOMs were disinserted from the globe at the buckle: 2 superior rectus, 2 medial rectus, and 1 lateral rectus. One patient with suspected inferior rectus muscle disinsertion had restrictive strabismus as a result of interference by a meridional explant and myopic staphyloma. Magnetic resonance imaging demonstrated anterior migration and transection by the silicone element through rectus EOMs in 3 patients. Disinserted EOMs were retrieved successfully by transconjunctival surgery in 4 patients and by orbitotomy in 1 patient, markedly improving alignment even as long as 5 years after EOM disinsertion. CONCLUSIONS: Multipositional high-resolution MRI provides valuable information such as location and contractile potential of disinserted EOMs, as well as mass effect from the scleral buckle. Preoperative orbital MRI may be a useful tool to distinguish multiple mechanisms of persistent severe strabismus after scleral buckling and is helpful in surgical planning.

Adult↗

PubMed2006

Intraoperative relaxed muscle positioning technique for strabismus repair in thyroid eye disease.

OBJECTIVE: To describe the outcomes of a relaxed muscle technique for treatment of dysthyroid strabismus. DESIGN: Retrospective consecutive case series. PARTICIPANTS: Twenty-four patients with thyroid-related orbitopathy (TRO) underwent strabismus surgery using a novel relaxed muscle technique. METHODS: Charts of all patients who underwent rectus muscle recession surgery using a relaxed muscle technique between 1997 and 2004 were reviewed. Twenty-four of 28 patients had more than 2 months of follow-up and were included. The extent of recession was determined by marking where the tendon naturally fell while the relaxed muscle rested freely on the globe with the eye in the primary position. The muscle was sutured to the globe at the mark. Linear regression was used to determine the correlation between the degree of strabismus and the amount of recession required to eliminate diplopia. MAIN OUTCOME MEASURES: Surgical outcomes were analyzed 2 months, 6 months, and 1 year after strabismus repair. Excellent success was defined as no diplopia in primary and reading gazes without prisms. Good outcome was defined as no diplopia in primary and reading positions with the use of <10 prism diopters. Poor outcome was defined as persistent diplopia in primary or reading positions despite prisms, or the inability of the patient to tolerate the necessary prisms. RESULTS: Twenty-four patients underwent 60 muscle recessions. Nine had diplopia without a history of orbital decompression, 8 had diplopia before decompression, and 7 developed diplopia only after orbital decompression. Twenty-one patients (87.5%) had an excellent final outcome. A clinically acceptable (excellent or good) final outcome was achieved in 24 of 24 patients (100%) after an average of 1.08 surgeries. All 7 patients who developed diplopia only after decompression had an excellent outcome. Linear regression did not show good correlation between the degree of strabismus and the amount of recession required to eliminate diplopia (maximum R2 = 0.7292). There were no complications. CONCLUSIONS: The relaxed muscle technique provides excellent ocular alignment and relief from diplopia in a majority of patients with TRO-associated strabismus. Patients who develop diplopia only after orbital decompression may have a higher success rate.

Adult↗

PubMed1997

Impairment of the binocular coordination of saccades in strabismus.

To examine the link between binocular vision and binocular coordination of saccades we studied subjects with convergent strabismus since childhood with mild or no amblyopia: three subjects had small squint (< 10 prism D) and preserved peripheral binocular visual function with gross stereopsis; four subjects had larger squint (18-35 prism D) and no detectable stereopsis. A standard paradigm was used to elicit horizontal saccades; binocular recordings were made with the IRIS device. For subjects with small strabismus, saccades were disconjugate (unequal between the two eyes) typically by 1 deg. Subjects with larger strabismus exhibited even larger and more variable disconjugacy (typically 1.8 deg). Post-saccadic eye drift was consistently divergent in subjects with small strabismus and tended to reduce the convergent squint angle. In contrast, in subjects with large strabismus drift was convergent. The impairment of the binocular control of saccades is attributed to the deficiency of disconjugate oculomotor adaptive capabilities necessary to compensate for the natural asymmetries or changes in the two oculomotor plants; such deficiency would be more severe in subjects with large strabismus who have neither central nor peripheral binocular vision.

Adult↗

PubMed1999

Early strabismus surgery for thyroid ophthalmopathy.

OBJECTIVE: To determine whether strabismus surgery during active thyroid ophthalmopathy is beneficial for selected patients. DESIGN: Case series. PARTICIPANTS: Eight patients with severe restrictive strabismus due to thyroid ophthalmopathy underwent early strabismus surgery and were followed for a minimum of 16 months after their initial surgery. INTERVENTION: All eight patients underwent strabismus surgery while their thyroid ophthalmopathy was evolving. MAIN OUTCOME MEASURES: Success was determined by the ability to fuse in the primary position at distance and near without an abnormal head position, and the absence of vision-threatening complications related to strabismus surgery. RESULTS: All eight patients achieved successful long-term alignment. Four patients (50%) required more than one operation. CONCLUSIONS: Strabismus surgery during active thyroid ophthalmopathy can result in long-term stable alignment and may be a useful alternative in selected patients with marked disability due to thyroid ophthalmopathy.

Adult↗

PubMed1998

Perianesthesia care of adult and pediatric strabismus surgery patients.

Strabismus procedures on children and adults are frequently performed in an outpatient setting. Perianesthesia care of patients having strabismus procedures may be optimized by recognizing the characteristics of strabismus patients, the frequently associated diagnoses that may affect perioperative care, and the specific surgical techniques used to treat strabismus. Complications including postoperative nausea, pain, prolonged PACU stay, and unplanned postoperative admissions can be minimized and treatment facilitated by preparing patients with preoperative instructions, careful choice of anesthetic agents and postoperative medications, and appropriate perioperative care. This report will provide a brief review of surgical strabismus, including current techniques, and present guidelines for perioperative care of pediatric and adult strabismus patients.

Adolescent↗

PubMed2003

Early versus delayed repair of infantile strabismus in macaque monkeys: I. ocular motor effects.

INTRODUCTION: The appropriate age for surgical correction of esotropic strabismus in human infants is controversial; some clinicians advocate surgery before age 6 months, and others recommend observation and surgery at older ages. Infantile (congenital) esotropia in humans and monkeys is known to be accompanied by a constellation of eye movement abnormalities caused by maldevelopment of cerebral visual motor pathways. The purpose of this study was to determine how early versus delayed correction of strabismus influences development and/or maldevelopment of these eye movement pathways. METHODS: Optical strabismus was created in infant macaques by fitting them with prism goggles on day 1 of life. The early correction group (2 experimental and 1 control) wore the goggles for a period of 3 weeks (the equivalent of 3 months before surgical repair in humans). The delayed correction group (3 experimental and 1 control) wore the goggles for a period of 3 or 6 months (the equivalent of 12 or 24 months before surgical repair in humans). Several months after the goggles were removed, the monkeys were trained to perform visual fixation, smooth pursuit, and optokinetic nystagmus (OKN) tasks for a juice reward. Eye movements were recorded using binocular search coils. The performance of the early versus delayed infant monkey groups was also compared with that of a group of adult monkeys who had unrepaired, naturally occurring infantile esotropia. RESULTS: Early correction monkeys developed normal eye movements and exhibited ocular motor behaviors that were indistinguishable from normal control animals. They regained normal binocular eye alignment and showed stable fixation (no latent nystagmus). Monocular horizontal smooth pursuit and large field OKN were symmetric. In contrast, delayed correction monkeys showed persistent esotropia, latent fixation nystagmus, dissociated vertical deviation, and pursuit/OKN asymmetry. Animals who had the longest delay in correction of the optical strabismus exhibited eye movement abnormalities as severe as those of adult animals with uncorrected, natural esotropia. CONCLUSIONS: Early correction of strabismus in primates prevents maldevelopment of eye movements driven by cerebral motor pathways. Our results provide additional evidence that early strabismus correction may be beneficial for brain development in human infants.

Animals↗

PubMed1998

Treatment of strabismus and nystagmus with botulinum toxin type A. An evaluation of effects and complications.

PURPOSE: Injection of botulinum toxin type A into eye muscles leads to a temporary paralysis and the effects have been evaluated in strabismus or nystagmus. METHOD: A total of 112 patients with different types of concomitant and paralytic strabismus and acquired nystagmus were treated with botulinum toxin, according to well-established indications. RESULTS: The lasting effects of the injections on strabismic angle were largest in esotropia, consecutive exotropia and abducens palsy, and amounted to, on an average, 12 prism diopters or 6 degrees. The larger the strabismus the better was the effect. Repeated injections reduced the angle further. In complex nystagmus forms retrobulbar injections could be used. The side effects were mostly due to spread of botulinum toxin to the levator, producing ptosis (8%), or the inferior rectus muscle, causing vertical strabismus (10%). On an average 42% of the patients were later operated for strabismus and nystagmus. CONCLUSION: Injection of botulinum toxin A into eye muscles is a valuable adjunct to surgery in the treatment of strabismus and nystagmus.

Adult↗

PubMed2001

Strabismus and binocular function in children with Down syndrome. A population-based, longitudinal study.

PURPOSE: We have performed a population-based, longitudinal study on strabismus in children with Down syndrome. The aims of the study were to examine the frequency and type of strabismus, the age at onset, and the binocular potential. METHODS: An unselected population of 60 children with Down syndrome born 1988-1999 was followed with repeated examinations. Mean follow-up time was 55+/-23 months (range 24--115). The alignment of the eyes was examined using Hirschberg corneal reflex test and cover test for near fixation. To evaluate binocular function, Titmus House Fly Test and Lang's stereo test were used. RESULTS: Twenty-five patients (42%) had strabismus (21 esotropias, two exodeviations and two vertical deviations). Only one case of infantile esotropia was found, the other esotropias were acquired forms. The mean age at "onset" (e.g. when strabismus was first noticed) was 54+/-35 months. In the acquired esotropia group (n=20), 15 (75%) were associated with hypermetropia (mean spherical equivalent +4.3+/-1.7 D). Seventeen of the strabismic patients had an accommodation weakness. Eleven of the strabismus patients gave a clearly positive response to one or both stereotests. CONCLUSIONS: The majority of the Down syndrome children with strabismus have an acquired esotropia and hence a potential for binocularity. Hypermetropia and accommodation weakness are probably important factors in esotropia in Down syndrome patients.

Accommodation, Ocular↗

PubMed2002

A study of heredity as a risk factor in strabismus.

AIMS: Inheritance is recognised to have a part in the aetiology of strabismus but previous studies have not adequately distinguished between different types of strabismus leading to wide variations in reported findings. The aim of this study was to investigate the importance of heredity in different types of strabismus. METHODS: The parents of children attending for treatment of strabismus over a one-month period were interviewed to identify relatives with a history of strabismus. A complete three-generation pedigree was established for 96 index cases who were classified into four groups: infantile esotropia (26 cases), accommodative esotropia (49 cases), anisometropic esotropia (15 cases), and exotropia (six cases). RESULTS: Forty-three of a total of 165 (26.1%) first degree relatives of patients with hypermetropic accommodative esotropia were affected. In contrast, 15 of a total of 101 (14.9%) first degree relatives of patients with infantile esotropia, eight of a total of 66 (12.1%) first degree relatives of patients with anisometropic esotropia, and one of a total of 25 (4%) first degree relatives of patients with exotropia were affected. Analysing the data using logistic regression with a random term for family showed a significantly higher proportion of affected first degree relatives in the accommodative group than in any of the other three diagnostic groups. CONCLUSION: A history of strabismus appears to be more common in hypermetropic accommodative esotropia than in infantile esotropia, anisometropic esotropia or exotropia. More detailed investigation of the role of heredity in the aetiology of accommodative esotropia is needed.

Child↗

PubMed2004

Adjustable and non-adjustable strabismus surgery: a retrospective case-matched study.

Adjustable suture strabismus surgery was introduced to improve results in unpredictable strabismus cases. However, its usage is increasing and in some centres is routine. The present authors propose that the routine use of the adjustable suture technique can only be justified if it can be shown to confer an advantage to the patient. In a retrospective analysis of matched data, they compared the results of their adjustable with non-adjustable strabismus surgery. The adjustable suture procedures performed during a 5-year period, on non-thyroid eye disease patients, were matched to non-adjustable cases according to the type and aetiology of strabismus and the magnitude of deviation. Pairs were matched as closely as possible according to age and strabismus surgery history. All cases were incomitant. The surgical results of the two groups were analysed with regard to the pre-operative and post-operative angles of deviation, the post-operative drift, and a successful outcome, pre-defined by carefully selected criteria. Twenty-six cases were analysed in each of the two groups. Mean pre- and post-operative angles of deviation showed no significant difference between the two groups. 'Success' rates were 81% in the adjustable group and 88% in the non-adjustable group. Given that the success rate of the two techniques is similarly high, a much larger study is required to detect a difference in results, with statistical significance. The authors conclude that there is currently insufficient evidence that patients, without thyroid eye disease, benefit from the longer and potentially uncomfortable procedure of adjustable suture strabismus surgery to support its rapidly growing use and that a prospective randomised controlled trial is indicated.

Adolescent↗

PubMed1993

Persistent diplopia associated with strabismus surgery.

The primary therapeutic goal for patients with binocular vision problems is comfortable, single, clear, normal binocular vision at all distances and directions of gaze. Strabismus surgery is frequently used to assist in achieving this therapeutic goal. Strabismus surgery is also used for those patients who cannot achieve single normal binocular vision but who have a cosmetically noticeable ocular deviation. However, one of the complications of cosmetic strabismus surgery is persistent diplopia. This possibility must be considered seriously before any cosmetic strabismus surgery is performed. The purpose of this paper is to present a case report of a patient who had diplopia after cosmetic strabismus surgery to emphasize the need for careful consideration of the possibility of persistent diplopia after cosmetic strabismus surgery and how to avoid it.

Adult↗

PubMed2004

Minimal angle horizontal strabismus detectable by lay observers.

PURPOSE: Patients with socially significant strabismus may be at risk for certain psychosocial consequences. However, the magnitude at which strabismus becomes socially significant is ill defined. Suggested criteria for socially significant strabismus can be found in the literature, but they are rarely, if ever, referenced. The purpose of this study is to further define the magnitude at which strabismus becomes socially significant according to lay observers. METHODS: Strabismus was simulated using photo manipulation and off-center fixation. Horizontal deviations were created in 3Delta steps up to 24Delta. One model was used for all photos. The photos were presented in random order to non-health care professionals (N = 58). Participants were instructed to view each picture and determine: "yes, this person has an eye turn" or "no, this person does not have an eye turn." A chi test was used for analysis. RESULTS.: There was an increase in the likelihood of strabismus detection as the size of the angle increased for exotropia and esotropia. Overall, exotropia was easier to identify than esotropia. For esotropia, a dramatic increase in detectability occurred between 9Delta (47.41% detection; p = 0.001) and 12Delta (67.24% detection; p = 0.001), with 70% detection being achieved at 14.5Delta. A significant increase in detection of exotropia occurred between 6Delta (60.34% detection; p = 0.001) and 9Delta (77.59% detection; p = 0.001), with 70% detection achieved at 8Delta. CONCLUSIONS: Our results suggest that exotropia is easier for lay observers to detect than esotropia, with the critical magnitude (70% detection) being 14.5Delta for esotropia and 8Delta for exotropia. This refutes generally accepted beliefs that esotropia is easier to detect than exotropia. Additional studies are needed to look at the effect of ethnicity, sex, and age. Multiple models should be used to reduce the possible influence of distinct facial characteristics and increase the generalizability of the results.

Diagnostic Techniques, Ophthalmological↗