20th annual Frank Costenbader Lecture--adult strabismus

Short-Term Morpho-Functional Changes before and after Strabismus Surgery in Children Using Structural Optical Coherence Tomography: A Pilot Study

PURPOSE

To evaluate the immediate alterations in the thickness of the macular ganglion cell-inner plexiform layer (mGCIPL), peripapillary retinal nerve fiber layer (RNFL), inner retinal layer (IRL), and outer retinal layer (ORL) using spectral domain optical coherence tomography (SD-OCT) subsequent to strabismus surgery in pediatric patients diagnosed with horizontal esotropia.

METHODS

Twenty-eight eyes from twenty-one child patients who had undergone uncomplicated horizontal rectus muscle surgery due to strabismus were included. Measurements of RNFL, mGCL-IPL, IRL, and ORL using structural OCT were conducted both before the surgery and one month after the surgical procedure. Importantly, a control group comprising 14 healthy eyes, matched for age and significant refractive error (<3.00 diopters), was included in the current analysis.

RESULTS

Our analysis indicated no significant disparity before and after surgery in terms of best-corrected visual acuity (BCVA), RNFL, IRL, and ORL. Conversely, concerning the macular ganglion cell layer-inner plexiform layer analysis, a substantial increase in mGCL-IPL was observed following the surgical intervention. The mean mGCL-IPL measured 60.8 ± 9.2 μm at baseline and 66.1 ± 13.2 μm one month after the surgery (p = 0.026). Notably, comparison between the strabismus group at baseline and the healthy group revealed a significant reduction in mGCL-IPL in the strabismus group (60.8 ± 9.2) compared to the healthy control group (68.3 ± 7.2; p = 0.014).

CONCLUSIONS

Following strabismus surgery, our observations pointed towards a thickening of the mGCL-IPL layer, which is likely attributable to transient local inflammation. Additionally, we identified a significant differentiation in the mGCL-IPL complex between the pediatric patient group with strabismus and the control group.

Binocular Function in Adults before and after Strabismus Surgery

PURPOSE

To evaluate the state of binocular vision, the amount and direction of the ocular deviation before and after strabismus surgery in adult patients and to monitor the occurrence of postoperative complications.

METHODS

The retrospective study of 58 adult patients with selected types of strabismus who were surgically treated in the Eye Department of the Tomas Bata Regional Hospital in Zlín. We evaluated the amount and the degree of the primary ocular deviation and the binocular alignment before and after surgery,  as well as the state of binocular vision after surgery and the occurrence of postoperative complications.

RESULTS

The average deviation in convergent strabismus before surgery was +23.46 degrees, after surgery +6.6 degrees, in divergent strabismus it was -21.5 degrees, after surgery -1.48 degrees, for vertical strabismus before surgery +12.5 degrees and +3.75 degrees after surgery and in paralytic strabismus +20 degrees before surgery and +3 degrees postoperatively. Preoperatively there was effectively no binocular vision in up to 63.9% of patients, superposition occurred in 31%, fusion in 5.1%. No patient had stereopsis before surgery. After surgery, superposition was present in 39.7%, fusion in 31% and stereopsis in 6.9% of patients. Only 22.4% of patients experienced no binocular vision after surgery. Of the selected 21 patients out of 58 with an observation period of at least 3 years, we observed an improvement or development of binocular vision functions after surgery in 12 patients and no improvement of binocular vision functions in 9 patients. In the first group, 58.3% had a stable deviation throughout the follow-up period. While in the second group the deviation was stable in only 33.3%. We can assume that the improvement in binocular vision function after strabismus surgery, leads to a greater longer-term stability of postoperative deviations.

CONCLUSION

Strabismus surgery in adult patients is an effective and safe method, which is not only a cosmetic procedure used to adjust the position of the eyes, but also enables us to induce or improve the state of binocular vision functions.

Adults with Longstanding Strabismus: Psychosocial and Functional Impacts and Reasons behind Surgery Delay

Purpose

The aims of the study were to determine the reasons behind surgical correction delay in adult patients with strabismus, reveal motivations for seeking treatment, and study the psychosocial and functional impacts of strabismus on patients using an Arabic version of the Adult Strabismus-20 (AS-20) questionnaire. Methods and Patients. This study included 79 patients aged ≥18 years and had strabismus for at least one year prior to surgical correction and 40 controls without known visual defects. After a comprehensive ophthalmic exam during their preoperative visit, a validated questionnaire was administered to patients to collect sociodemographic data, reasons for surgery delay, and motivations for seeking treatment now. A translated version of the AS-20 questionnaire was then presented to patients and controls. Total AS-20 (and its subscales: psychosocial and function) scores were calculated and analyzed. All relationships between sociodemographic characteristics, the onset of deviation, presence of diplopia, type and size of deviation, and the changes in the scores of AS-20 (and its subscales) were investigated.

Results

A total of 79 adult patients with strabismus (cases) and 40 subjects with normal vision (control group) were included in this study. The mean age (SD) was 34.10 (11.5) years for cases (range: 18–61) and 34.20 (11.2) years for controls (range: 18–65) (p=0.964). About half (55.7%, n = 44) of the patients were males compared to (57.5%, n = 23) of the controls. The reasons for strabismus surgery delay reported by the patients were the following: surgery was not offered by an ophthalmologist (35.4%), surgery was offered but declined by the patient due to fear from surgical complications (22.8%), nonaffordability (17.7%), surgery was offered but refused because patients thought they were too old for surgery or patient was not bothered by appearance (15.2%), and patient never sought care (8.9%). The reasons for seeking surgical treatment after this delay were as follows: for cosmetic issues (27.8%), a better understanding of strabismus surgery and its potential complications (20.3%), pressure from family and friends (16.5%), improved economic status (13.9%), relationship/marriage prospects (13.9%), and to improve chances of getting a job (7.6%). When compared to control, patients have significantly lower mean scores of total AS-20 (50.57 vs. 88.01) and its psychosocial (49.59 vs. 87.84) and functional (51.55 vs. 88.19) subscales. AS-20 total score was significantly lower among females and in patients with large deviation size (>25 PD). The psychosocial subscale of AS-20 was significantly lower in females, patients with younger age of onset, and those with large deviation size (>25 PD). Female gender, large deviation size, vertical deviation, and having diplopia correlated significantly with a lower functional score.

Conclusion

Strabismus has a profound psychosocial and functional impact on affected individuals, especially females and patients with large deviation sizes. Many adult patients with strabismus tend to delay surgical correction; most of these delays could be avoided by better public education, increased awareness among health care providers, and changing health insurance policies to cover the costs of strabismus surgery.

Factors Determining Improvement in Stereopsis and Binocularity After Good Postoperative Alignment in Patients With Childhood-Onset Strabismus

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 gender, refractive error, and duration of strabismus. Patients who had strabismus after six months of age noticed a significant improvement in stereopsis (p-value = 0.000) than those who had strabismus before six months of age (p-value = 0.660). Further, there was a statistically significant improvement in patients having exotropia (p-value = 0.018) or combined horizontal and vertical deviations (p-value = 0.000), but there was no significant improvement in patients with esotropia (p-value = 0.180). Moreover, non-amblyopes had a significantly better postoperative stereopsis than amblyopes (p-value = 0.006). Although there was no association between preoperative deviation and improvement in stereopsis (p-value = 0.081), patients having preoperative deviation in the range of 31-45 PD had a statistically significant improvement in stereopsis (p-value = 0.000). There was no significant difference between postoperative residual deviation and final stereopsis (p-value > 0.05). All the results were the same for both the Titmus test and the random dot test. Binocular fusion was observed in 34 subjects, and uniocular suppression was noted in 38 subjects preoperatively. It was observed that only one patient gained binocular single vision postoperatively.

Conclusion: The presence of amblyopia, esotropia, early onset of strabismus (within six months of age), and a larger preoperative deviation (>45 PD) were associated with poorer stereopsis. In patients with horizontal strabismus, the coexistence of vertical deviation had a positive impact on the postoperative stereopsis. Gender, refractive error, and duration of strabismus did not influence the final stereopsis in our study.

Predictive factors of stereopsis outcomes following strabismus surgery

Purpose:

To determine the predictive factors of post-operative stereopsis in patients with strabismus.

Method:

In this retrospective study, records of patients who received surgical treatment for strabismus were reviewed. All types of strabismus were included. Pre- and post-treatment stereoacuity were measured using the Titmus Stereo Fly test, and predictive factors of stereopsis were evaluated.

Results:

A total of 194 patients (132 females and 62 males) with a mean age of 14.8 ± 8.4 years were included. There was a statistically significant improvement in stereopsis following surgery (p value < 0.001). Patients with a higher amount of deviation at baseline had poorer stereopsis on the final examination (p value < 0.001). Stereopsis improvement was more prominent in the pure horizontal strabismus group, compared to combined horizontal and vertical deviations. Baseline and the final stereopsis were higher in the “exotropia” group as compared to the “esotropia” group (p value = 0.003 and 0.0155, respectively); however, the within group change of stereopsis was not significantly different between these two groups (p value = 0.144). Post surgical residual deviation was associated with a poorer stereopsis (p value = 0.002, r = 0.251). A longer duration of strabismus before surgery was associated with poorer final stereopsis levels (p value = 0.026). The presence of amblyopia before surgery was associated with poorer stereopsis on last examination (p value < 0.001 for both correlations).

Conclusion:

Based on the result of this study, final stereopsis after strabismus surgery could be affected by the type, duration, and the amount of deviation before surgery, amblyopia, and post operative ocular deviation.

Late Surgical Correction of Longstanding Constant Strabismus in Adults: Is Fusion Possible in All Successfully Aligned Patients?

PURPOSE

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.

Diplopia after strabismus surgery for adults with nondiplopic childhood-onset strabismus

PURPOSE

To describe frequency of postoperative diplopia after strabismus surgery in nondiplopic adults with childhood-onset strabismus and to report health-related quality-of-life (HRQOL) outcomes.

METHODS

We prospectively enrolled 79 adults with no diplopia in any gaze who had childhood-onset strabismus and were scheduled for strabismus surgery. Diplopia was assessed preoperatively and at 6 weeks and 1 year postoperatively using a standardized diplopia questionnaire with 5 response options in 7 gaze positions. HRQOL was assessed using the Adult Strabismus-20 (AS-20) questionnaire, with self-perception, interactions, reading function, and general function domains.

RESULTS

Constant diplopia in straight-ahead distance and reading gaze occurred in 1 patient (1% [95% CI, 0%-7%] at 6 weeks and 2% [95% CI, 0%-10%] at 1 year). Regarding the rate of any diplopia (including rarely) in any gaze, 15 of 78 patients (19%) reported diplopia at 6 weeks, of whom 13 had diplopia in straight-ahead distance gaze; 8 (10%), in reading gaze. At 1 year, 8 of 51 patients (16%) reported any diplopia (including rarely) in any gaze, of whom 7 had diplopia in straight-ahead distance gaze and 4 (8%) in reading gaze. Mean AS-20 scores improved at 1 year overall (by 32, 19, 14, and 15 points, resp., per domain) and for the 8 diplopic patients (by 21, 13, 16, and 11 points).

CONCLUSIONS

In adults with nondiplopic strabismus, constant postoperative diplopia is rare, although the rate of intermittent diplopia is higher. Even when postoperative diplopia occurs, HRQOL often improves.

Adult-onset nonparalytic, small-angle hypertropia

PURPOSE

To describe the prevalence and clinical features of a common but underrecognized disorder of adult vertical strabismus.

METHODS

The medical records of all adult (≥19 years of age) residents of Olmsted County, Minnesota, diagnosed with nonparalytic, small-angle hypertropia (NPSAH) from January 1, 1985, through December 31, 2004, were retrospectively reviewed for demographic and clinical features.

RESULTS

Of 753 patients diagnosed with adult-onset strabismus, 99 (13.1%) were found to have NPSAH, yielding an annual incidence of 7.50 per 100,000 patients >18 years of age and a cumulative incidence of 1.28%. The median age at diagnosis was 71 years (range, 27-98 years); 63 (64%) were women. Diplopia was reported at the initial diagnosis in 91 patients (93.8%), with 90 (92.8%) having the diplopia in primary or reading position. The median initial angle of hypertropia was 2^Δ (range, 1^Δ-22^Δ) at near and 2^Δ (range, 0^Δ-12^Δ) at distance. After a median follow-up of 10.8 years (range, 6.2 months to 23.7 years), the final median angle of vertical deviation was 4^Δ (range, 0^Δ-20^Δ) at near and 4^Δ (range, 0^Δ-16^Δ) at distance for all 99 patients.

CONCLUSIONS

NPSAH is a relatively common but infrequently recognized disorder among adults. More prevalent among elderly and female patients in this study cohort, the vast majority presented with diplopia and a hypertropia of ≤10^Δ that progressed over time.

Double vision in adults

PURPOSE

To determine the patient characteristics, patterns in presentation and incidences of the various etiologies in adult patients with the chief complaint of double vision.

DESIGN

Retrospective review.

SUBJECTS

All persons greater than 18 years of age who presented to a single provider (DG) in a nonacademic private practice over a 2-year period, from 2011 to 2013, with the chief complaint of double vision. The provider is part of a multispecialty eye care group practice with both ophthalmologists and optometrists. This group practice provides a large adult referral base.

METHODS

Examination for each patient included refraction, versions, alignment in different positions of gaze at distance and at near, binocular sensory testing, neuro-ophthalmologic examination, and dilated fundus examination if not recently documented. Alignment was measured with cover-uncover testing and alternate cover testing with prism bars or free prisms, using Snellen letters for fixation. Appropriate refractive correction was ensured. Alignment was measured in the primary position at distance and in gaze directed 20 degrees L, R, up, and down. The near deviation was measured in the reading position with the large letters on a near card for fixation. Sensory testing was performed with the Worth 4-dot at distance and near and with the Titmus stereopsis test. Vectograph testing was also performed at distance on many patients, particularly those with small-angle deviations. The prismatic correction necessary to correct diplopia subjectively at distance in the primary position and at near in the reading position was also recorded.

PRIMARY OUTCOME

Ocular alignment and etiology of diplopia. Management, response to treatment, and outcome were also recorded.

RESULTS

A total of 125 patients were included in the analysis. Subjects ranged from 18 to 93 years of age. Most cases of idiopathic strabismus were in the elderly, but the age range varied with category of underlying strabismus. Small-angle HT was the most common type of strabismus, comprising 21% of all subjects. ET, usually of the divergence insufficiency type (20%); XT (14%); and palsies not including trochlear palsy (12%) and trochlear palsy (8%) were the next most common etiologies. No strabismus was found in 11% of subjects.

CONCLUSIONS

Most cases of diplopia in adults presenting as an outpatient can be classified into a few categories based on their type of strabismus. These categories of strabismus share typical age ranges and features. While diplopia in adults is usually idiopathic, diplopia can be the presenting sign of serious underlying pathology. Thus, a thorough history; examination; and, in some cases, diagnostic testing is necessary.

The Functional Benefits of Strabismus Surgery

When performed prior to visual maturity, strabismus surgery can result in the development or recovery of binocularity. When strabismus surgery is performed after visual maturity, the functional benefits of the surgery should be dichotomized according to whether the onset of the strabismus was before or after visual maturity. If the onset was after visual maturity, patients typically are diplopic. Specific success rates for eliminating diplopia vary according to the nature of the strabismus; however, overall the success rate is quite high. There is a common misperception that surgery in adults for strabismus that began prior to visual maturity is merely cosmetic. Numerous studies contradict this misconception. Even if the strabismus has been longstanding, most adults will experience some improvement in binocular function after strabismus surgery. In esotropic patients, this improvement typically takes the form of an expansion of binocular visual fields; however, some patients may also regain stereopsis. There are many psychosocial benefits to adult strabismus surgery. This is reflected in the finding that the majority of adults surveyed with strabismus would trade a portion of their life expectancy to be rid of their strabismus.

An Assessment of Stereovision Acquired in Adulthood

SIGNIFICANCE

Increasing evidence indicates that childhood binocular vision disorders that lead to stereodeficiency may be treated in adulthood. Reports of patients who gain stereopsis as adults indicate that this achievement provides for a qualitatively different and dramatically improved sense of space and depth.

PURPOSE

Increasing evidence suggests that stereopsis can be achieved in adult patients despite long-standing binocular disorders. We polled individuals who gained stereopsis as adults to ascertain their initial binocular disorders, the length of time they were stereodeficient, effective treatments, and the nature of their recovered stereovision.

METHODS

A questionnaire was posted online and announced in a brief article in the journal Vision Development and Rehabilitation.

RESULTS

Of the 63 responders, 56 (89%) reported strabismus and/or amblyopia, and 55 (87%) indicated that they had been stereodeficient for as long as they could remember. All but seven participants (89%) achieved stereovision through vision training or a combination of surgery and vision training, and many reported vivid visual changes.

CONCLUSIONS

Despite childhood binocular disorders, patients may be able to achieve stereopsis following interventions in adulthood. This achievement provides for a qualitatively different and dramatically improved sense of space and depth.

Surgical Treatment of Adult-Onset Esotropia: Characteristics and Outcomes

PURPOSE

To describe the characteristics of the strabismus, surgical management, and outcomes of patients who underwent surgery for adult-onset esotropia.

METHODS

This was a retrospective case study of patients at an academic tertiary referral center who underwent surgical treatment of esotropia acquired at or after age 18 years. Primary outcome measures were resolution of diplopia in primary position and a deviation of 10 prism diopters or less in primary gaze. Additional clinical parameters were assessed.

RESULTS

Of 248 patients with adult-onset esotropia who underwent strabismus surgery, all experienced diplopia preoperatively except those with sensory esotropia. The four most common diagnoses were cranial nerve VI palsy in 36% (90 of 248), thyroid eye disease in 18% (45 of 248), age-related distance esotropia in 15% (38 of 248), and decompensated latent esodeviations in 13% (31 of 248) of patients. A variety of surgical procedures were employed, and adjustable sutures were used in 79% (196 of 248). Approximately 80% (158 of 197) of patients present at the 2-month postoperative follow-up visit were aligned within 10 prism diopters, and 72% (140 of 195) experienced resolution of diplopia. Success rates were significantly higher in patients with adjustable sutures. Reoperation rates were low overall at 15% (37 of 248) and were highest in cranial nerve VI palsies and lowest in age-related distance esotropia. Dose-response calculations showed a non-significantly smaller effect per millimeter of recession and resection in cranial nerve VI palsy and age-related distance esotropia.

CONCLUSIONS

The causes of adult-onset esotropia are diverse. A variety of surgical approaches are employed and, in conjunction with adjustable sutures, provide a good rate of diplopia resolution and acceptable ocular alignment. [J Pediatr Ophthalmol Strabismus. 2017;54(2):104-111.].

Factors associated with surgical success in adult patients with exotropia

PURPOSE

To report the results of surgical treatment for intermittent or constant comitant exotropia in adults and to examine the factors associated with the surgical outcome.

METHODS

The medical records of consecutive patients older than 18 years of age at the time of surgery for intermittent or constant comitant exotropia and with at least 1 year's follow-up were retrospectively reviewed. Surgical success was defined as postoperative esodeviation of <5^Δ, orthotropia, or exodeviation of <10^Δ. Overcorrection (defined as esodeviation >5^Δ) and recurrence (exodeviation of >10^Δ) were considered surgical failure. Preoperative patient characteristics, surgical procedures performed, and early postoperative ocular alignment were evaluated as potential factors associated with the surgical outcome.

RESULTS

A total of 39 patients were included, of whom 28 (72%) achieved surgical success, 7 (18%) showed overcorrection, and 4 (10%) had recurrence. Alignment at postoperative week 1 was the only significant factor correlated with surgical results. Surgical outcome was best with early postoperative alignment of <10^Δ of esotropia.

CONCLUSIONS

Early postoperative overcorrection of <10^Δ resulted in more favorable surgical outcomes in adults undergoing surgery to treat exotropia.

Impact of strabismus surgery on health-related quality of life in adults

PURPOSE OF REVIEW

Adult strabismus can cause many symptoms, which have generally been divided into functional complaints and social complaints. The validity of surgical correction has historically been based on the restoration of functional improvement. In the absence of this expectation, surgery was labeled cosmetic. Yet, many studies have revealed the immense impact of ocular misalignment on psychosocial variables. The purpose of this article is to review the potential functional and psychosocial benefits of strabismus surgery and to summarize the development and status of questionnaires to help quantify these benefits.

RECENT FINDINGS

Functional benefits of strabismus surgery have been recently summarized with a meta-analysis. Several questionnaires have been evaluated to assess the functional and psychosocial factors in adult strabismus. Two strabismus-specific questionnaires, the Amblyopia and Strabismus Questionnaire and the Adult Strabismus-20, reveal improvements in adults following surgery. The appropriate patient population, impact of comorbidities on the scores, and the timing of the administration of the questionnaire postoperatively still need to be determined.

SUMMARY

Future studies of the impact of strabismus surgery in adults will need to report not only objective motor results, but also the impact on health-related quality of life to encompass all the benefits of strabismus surgery.

Predictors of Good Motor and Sensory Outcomes Following Strabismus Surgery for Patients with Third Nerve Palsies

Strabismus from third nerve palsy (3NP) is difficult to treat. Our goal was to explore factors associated with successful surgical outcomes in 3NP. Institutional records of all adult patients (>18 years) from 1988 to 2012 with 3NP who underwent strabismus surgery or botulinum toxin injections were retrospectively reviewed. Success was defined as absence of diplopia, vertical deviation ≤2 prism dioptres (PD), and horizontal deviation ≤10 PD. Fifty-six patients from four surgeons were included. Thirty (54%) were female; mean age was 48 (range: 20-80). Forty-four (79%) had unilateral 3NP; 9 (16%) had other ocular motor nerve palsies. 3NP were complete in 24 (43%). Underlying aetiology was idiopathic/microvascular in 5 (9%), traumatic in 13 (23%), neoplastic in 12 (21%), aneurysmal in 10 (18%), and other central nervous system related in 16 (29%). Trauma was associated more frequently with aberrant regeneration than other aetiologies: 9/13 (69%) versus 4/43 (9%) (p < 0.01). Ten patients (18%) had >1 surgery. Surgical success was achieved in 28/56 (50%). Success rate was unaffected by aetiology, degree of palsy, pupillary involvement, presence of aberrant regeneration, or number of other cranial nerves involved. However, adjustable sutures were used in 27 patients (48%), and there was a trend toward higher success rates when adjustable versus nonadjustable sutures were used (63% versus 38%; p = 0.06). Unlike with sixth nerve palsies, the aetiology and degree of 3NP does not appear to affect the success rates or number of procedures performed. Strabismus surgeries for 3NP with adjustable sutures may be associated with better outcomes.

Functional and Motor Outcomes of Strabismus Surgery for Chronic Isolated Adult Sixth Nerve Palsy

Abducens nerve palsy is the most common acquired ocular motor nerve palsy in adults. Chronic cases of abducens palsy often require surgical intervention to relieve disabling diplopia. The goal of this study was to identify factors associated with surgical outcomes in isolated abducens palsy. Medical records of all adult patients from 1988 to 2012 with abducens palsies who underwent strabismus procedures were retrospectively reviewed. Motor alignment, extraocular motility, and sensory outcomes were recorded. Success was defined as absence of diplopia without prisms or face turn, vertical deviation ≤2 prism dioptres (PD), and horizontal deviation ≤10 PD. Eighty-one patients (age range: 20-86 years) met inclusion criteria. Success was achieved in 58% of patients. Final success rates for abducens palsy were 50% for neoplastic, 59% traumatic, 57% for microvascular/unknown, and 67% for other central nervous system causes (p > 0.05). Patients with an underlying neoplastic or traumatic aetiology required more than one strabismus procedure more often than those with microvascular/idiopathic or other central nervous system causes (48% vs. 24%; p = 0.03). For complete abducens palsies, patients who underwent Hummelsheim-type procedures had a higher success rate than those who underwent a full-tendon vertical rectus muscle transposition. (78% versus 35%; p = 0.049). Success rates for strabismus procedures in patients with abducens palsies are similar across all aetiologies. Frequency of re-operation is higher among those patients with neoplastic or traumatic aetiologies for their abducens palsies. Hummelsheim-type procedures have a higher success rate for complete abducens palsies than full-tendon vertical rectus transpositions.

Surgical outcome of strabismus surgery in patients with unilateral vision loss and horizontal strabismus

PURPOSE

To report on the surgical outcome of horizontal strabismus surgery in patients diagnosed as having unilateral vision loss.

METHODS

Medical records of all patients with unilateral vision loss who underwent surgical repair of horizontal strabismus between 2008 and 2013 at three medical centers were reviewed. Data collected included age at time of surgery, type of strabismus, preoperative and postoperative deviation, procedure performed, and length of follow-up. Surgical success was defined as final alignment of 10 prism diopters (PD) or less unless more than one surgery was required to realign the eyes.

RESULTS

Twenty-one patients (9 children) were reviewed. Mean age at time of surgery was 28.3 years (range: 3 to 64 years) and mean follow-up was 20 months (range: 6 months to 5 years). Mean preoperative logMAR visual acuity in the deviating eyes (14 right eyes) was 1.4 ± 0.7 (range: 1.0 to 2.8) and mean deviation was 33 PD (range: 15 to 90 PD). All procedures were performed only on the deviating eye (13 recessions and 8 recession-resection procedures). Mean postoperative deviation was 6.4 PD (range: 0 to 25 PD) and 81% of patients had a manifest ocular deviation of 10 PD or less. Surgical success was comparable in children versus adults (P = .603), in patients with esotropia versus exotropia (P = 1.000), in patients with preoperative deviations larger than 30 PD compared to patients with smaller deviations (P = .521), and in patients in whom one muscle was operated on compared to all other patients (P = .617).

CONCLUSIONS

Strabismus surgery in patients with unilateral vision loss is often successful in correcting ocular misalignment.

Incidence, types, and lifetime risk of adult-onset strabismus

OBJECTIVE

To describe the incidence and types of adult-onset strabismus in a geographically defined population.

DESIGN

Retrospectively reviewed population-based cohort.

PARTICIPANTS

All adult (≥19 years of age) residents of Olmsted County, Minnesota, diagnosed with new-onset adult strabismus from January 1, 1985, through December 31, 2004.

METHODS

The medical records of all potential cases identified by the resources of the Rochester Epidemiology Project were reviewed.

MAIN OUTCOME MEASURES

Incidence rates for adult-onset strabismus and its types.

RESULTS

Seven hundred fifty-three cases of new-onset adult strabismus were identified during the 20-year period, yielding an annual age- and gender-adjusted incidence rate of 54.1 cases (95% confidence interval, 50.2-58.0) per 100 000 individuals 19 years of age and older. The 4 most common types of new-onset strabismus were paralytic (44.2% of cases), convergence insufficiency (15.7%), small-angle hypertropia (13.3%), and divergence insufficiency (10.6%). The incidence of adult-onset strabismus overall and its 4 most common forms significantly increased with age (P <0.001 for all), with a peak incidence in the eighth decade of life. The lifetime risk of being diagnosed with adult-onset strabismus was 4.0% in women and 3.9% in men.

CONCLUSIONS

Paralytic strabismus was the most common subtype of new-onset adult strabismus in this population-based cohort. All of the most common forms of adult-onset strabismus increased with age, especially after the sixth decade of life. Further characterization of strabismus types found in this study is warranted to better define this disorder.

Improvement in specific function-related quality-of-life concerns after strabismus surgery in nondiplopic adults

BACKGROUND

We have previously reported improvement in psychosocial scores after strabismus surgery on the patient-derived health-related quality of life (HRQOL) Adult Strabismus 20 (AS-20) questionnaire in adults with nondiplopic strabismus. Unexpectedly, we also found improvement in the function domain. The aim of the present study was to identify which specific aspects of function-related quality of life improved postoperatively.

METHODS

We retrospectively identified non diplopic adult patients with a history of childhood onset strabismus who underwent surgery and who had preoperative and 1-year postoperative AS-20 questionnaires (scored from 0 [worst] to 100 [best]). Change in scores for each item was evaluated using signed-rank tests.

RESULTS

A total of 20 patients were included. Of the 10 function-related AS-20 items, 9 showed significant mean improvement postoperatively (improvement ranged from 12.5 to 32.5 points, all P < 0.05). Rasch-derived mean scores improved in both reading function and general function domains (71.0 to 86.5 and 66.4 to 87.5, respectively; both P < 0.0001). Specific areas of function-related benefit were concentration, depth perception, hobbies, strain, reading, stress, and worry.

CONCLUSIONS

We found specific function-related quality of life benefits after strabismus surgery in nondiplopic adult patients, particularly those with childhood onset strabismus.

Utility of adjustable sutures in primary strabismus surgery and reoperations

PURPOSE

To evaluate the success of adjustable suture (AS) and nonadjustable suture (NAS) strabismus surgery in primary procedures and reoperations.

DESIGN

Retrospective case series.

PARTICIPANTS

Four hundred four patients older than 12 years who underwent strabismus surgery over a 13-year period.

METHODS

All eyes underwent the same hang-back suturing technique by a single surgeon (S.P.K.) in both the AS and NAS groups. Success was defined as alignment within 10 prism diopters (PD) for horizontal recti and within 5 PD of orthophoria for vertical recti without diplopia or further surgery.

MAIN OUTCOME MEASURES

Surgical success rate of AS and NAS primary surgery or reoperations was the primary outcome measure. Effects of amblyopia, binocularity, and strabismus type on success were secondary outcome measures and were analyzed using multiple logistic regression.

RESULTS

Patients in the AS group required adjustment in 28.8% of cases. Higher overall success was seen with AS (77.7%) compared with NAS (69.1%) surgery, although this did not reach significance (P = 0.059). Overall success for AS in exotropia surgery (80.8%) was significantly higher than that in the NAS group (65.9%; P = 0.011). This was because of higher success in patients undergoing primary surgery (82.5% vs. 50%; P = 0.003), but not in patients undergoing reoperation (80.2% vs. 77.6%; P = 0.71). On multiple regression analysis, male gender and not having a mechanical or neurogenic cause for strabismus were significant factors for a successful outcome. Overall, other factors including amblyopia, binocularity, strabismus type, and primary or reoperation were not significant.

CONCLUSIONS

These results suggest that primary surgery in adults with exotropia has a more successful outcome with AS surgery. This advantage was not present with esotropia and vertical deviations in this series.

[Horizontal sensory strabismus: characteristics and treatment results]

PURPOSE

To study the types of horizontal sensory strabismus, their causes, and treatment outcomes.

METHODS

A retrospective analysis of 44 patients with horizontal sensory strabismus who were treated from 2002 to 2007. Patients whose worse eye vision was inferior or equal to 0.2 were included. The deviation angle in primary position, causes, type of treatment, and pre-operative or post-operative diplopia were studied. A good result was considered if the final deviation was less than 10 prism diopters (pd).

RESULTS

Of the patients studied, 63.6% had exotropia and the 36.4% had esotropia. The visual acuity was between 0.1 and no light perception in 75% of patients. The causes responsible for low vision were congenital in 28, and acquired in 16 cases. The mean deviation was 46.7 pd. Diplopia was present in 5 cases, which were resolved with surgical treatment in 3 of them. The eye with reduced vision was operated on in 37 patients, both eyes in 6 cases, and botulinum toxin was injected in 1 case. The final outcome was successful in 90.6% of the cases which were surgically treated. The mean follow up was 31.84 months.

CONCLUSIONS

There were twice as many exotropias as esotropias. Strabismus surgery of the amblyopic eye shows excellent results without the need of new operations. There were no new diplopia cases.

Outcome of surgery in long-standing infantile esotropia with cross fixation

BACKGROUND

This is a retrospective study to determine the outcomes of the surgical correction in long-standing infantile esotropia with cross fixation.

METHODS

Medical charts of a group of patients with esotropia who had cross fixation and underwent surgery for strabismus between January 1991 and December 2004 were reviewed. The mean follow-up time was 4.7 years. Binocularity was measured by the Worth 4-dot test and Titmus stereo test. Twenty-six patients underwent surgery for strabismus. Twenty-one patients aged 8 to 26 years with a minimum 3-year postoperative follow-up were included. Five patients were excluded because they were lost to follow-up after surgery.

RESULTS

Bimedial recession and resection of one lateral rectus muscle were performed in all patients. Recession of the inferior oblique muscle with anteriorization was performed in patients who had inferior oblique overaction. Orthotropia was attained in 14 patients, whereas residual esotropia was diagnosed in 5 patients. Two patients were diagnosed as having exotropia. Two patients required a second surgery for dissociated vertical deviation. Overall, 9 of the 21 patients had indications of binocular function and 12 remained the same in their stereoacuity.

CONCLUSION

Surgical correction of long-standing infantile esotropia with cross fixation in young adults may improve binocular function and allow long-term alignment stability.

Results of re-operation on the deviated eye in patients with sensory heterotropia

Purpose

To evaluate the result of re-operation on the deviated eye of recurred, consecutive or undercorrected sensory strabismus after surgery.

Methods

The medical records of 11 patients who had received second strabismus operation on the deviated eye due to recurred, consecutive or undercorrected sensory strabismus were studied retrospectively.

Results

Among the 11 patients, five patients were operated for recurred exotropia after surgery of sensory exotropia (group 1), two for consecutive exotropia after surgery of sensory esotropia (group 2), and four for undercorrected esotropia after surgery of sensory esotropia (group 3). Re-operation was performed 19.2±12.6 years after the first operation and the mean preoperative deviation before re-operation was 30.0±8.66 prism diopters (PD), 32.5±10.6PD, and 32.5±8.66PD, respectively. In all cases, a small amount of recession or resection compared with the usual surgical dosage was applied in re-operation on the deviated eye. The mean follow-up period after re-operation was 12.3±14.2 (1-48 months). Among the 11 patients, postoperative deviations less than 10PD were achieved postoperatively in 8 (72.7%) at 1 month and of the 8 patients with follow-up data beyond 6 months, 5 (62.5%) showed orthotropia within 10PD at 6 months or later.

Conclusions

The surgical result of re-operation on the deviated eye of recurred, consecutive or undercorrected sensory strabismus after the first surgery was satisfactory in spite of the reduced amount of surgical correction compared with the surgical dosage recommended for the non-operated eye.

Botulinum toxin injection for postoperative diplopia testing in adult strabismus

PURPOSE

To investigate the use of botulinum toxin type A in identifying adult patients with constant strabismus who are at high risk of developing intractable diplopia after surgery.

METHODS

A retrospective review of adult patients with constant horizontal strabismus who had botulinum toxin injection to evaluate their risk of postoperative diplopia. These patients reported diplopia when prisms were used to neutralize the deviation.

RESULTS

One hundred ninety-five adults were studied; their mean age was 40.3 +/- 14 years (range, 16 to 73 years). One hundred thirty-three (68%) had botulinum toxin injected into a lateral rectus muscle; 62 (32%) had injections in a medial rectus muscle. Only 14 (7%) developed diplopia; 9 (4.6%) of these had troublesome diplopia but 5 (2.6%) could cope with the double vision and elected to have surgery. Surgical correction was recommended to the remaining 181 (93%) who did not experience diplopia. Complications of botulinum toxin injection were ptosis (10 patients, 5.1%) and superior oblique muscle weakness (3 patients, 1.5%). Twenty-six patients (13.3%) had a poor response to the first injection and required a second injection with a double dose. Surgery did not result in intractable diplopia after 6 weeks in any patient with a negative botulinum toxin diplopia test.

CONCLUSIONS

Botulinum toxin is a useful diagnostic tool for identifying patients with a low risk or no risk of postoperative diplopia despite a positive prism diplopia test.

Motor coordination in children with congenital strabismus: effects of late surgery

BACKGROUND

Strabismus is one of the most common visual disorders in infancy. While there is a great attention on the effects of the timing of surgery as to the development of binocular vision, little is known about the possible influence of congenital strabismus on perceptual-motor and more generally, on neuromotor development.

AIMS

Aim of this study was to investigate perceptual-motor and motor coordination abilities of 19 children with essential congenital esotropia who underwent a late surgery (after 4 years), compared to 23 age-matched controls.

METHODS

Children were tested using the Movement Assessment Battery for Children (Movement ABC) that were performed both 1-week before surgery (T1) and about 3 months (+/-2 weeks) after surgery (T2).

RESULTS AND CONCLUSIONS

At T1, abnormal or borderline results were found in more than half of the children with strabismus, as opposed to only about 17% of the controls. At T2 none of the children showed abnormal Movement ABC total scores and there was no difference in global scores between the study and the control group. The two groups also did not show any significant difference in individual items of the movement ABC with the exception of those assessing ball skills. Our results suggest that surgical correction of strabismus, even when performed after the 4th year of life, appears to be effective in improving perceptual-motor and motor function.

The cost utility of strabismus surgery in adults

PURPOSE

Cost-utility analysis evaluates the cost of medical care in relation to the gain in quality-adjusted life years (QALYs). Our purpose was to develop a cost model for surgical care for adult strabismus, to estimate the mean cost per case, to determine the associated gain in QALYs, and to perform cost-utility analysis.

METHODS

A cost model incorporated surgery, pre- and postoperative care, and a mean of 1.5 procedures per patient. The gain in QALYs was based on the improvement of utility on a scale from 0 (death) to 1 (perfect health). Utility was measured through physician-conducted interviews employing a time tradeoff question (seeking to estimate the portion of life expectancy a patient would be willing to trade for being rid of disease and associated effects). The interviews were conducted before and 5 to 8 weeks after surgery in 35 strabismic patients (age 19-75 years).

RESULTS

The cost model resulted in an estimated total cost of 4,254 dollars per case. A significant improvement of utility was found: 0.96 +/- 0.11 postoperatively versus 0.85 +/- 0.20 preoperatively (p = 0.00008). Based on the mean life expectancy (36.0 years) of these patients, and discounting outcomes and costs by 3% annually, this resulted in a mean value gain of 2.61 QALYs after surgery and a cost-utility for strabismus surgery of 1,632 dollas/QALY.

CONCLUSIONS

In the United States, treatments <50,000 dollars/QALY are generally considered "very cost-effective." Strabismus surgery in adults falls well within this range.

Factors affecting sensory functions after successful postoperative ocular alignment of acquired esotropia

PURPOSE

We sought to evaluate the sensory status of patients with acquired esotropia who were able to re-establish stable alignment by optical correction and surgery and to determine the possible predictors of the different sensory outcomes.

METHODS

Thirty-four successfully aligned esotropic patients were included in the study. Preoperative evaluation comprised history taking, measurement of visual acuity, evaluation of the sensory status (using the Worth 4-Dot test, and the Titmus Stereo test), measurement of ocular deviation, cycloplegic refraction, and fundus examination. All patients underwent successful surgical alignment to within 10 prism diopters (Delta) of orthotropia. At each postoperative follow-up visit, the sensory functions and ocular alignment were assessed. Statistical analysis of the results was performed.

RESULTS

Among the 34 patients included in the study, 62% achieved fusion, 17% had diplopia, 15% had suppression, and 6% had a variable response to the Worth 4-Dot test at 6 months after surgery. Stereopsis was achieved in 32% as determined by the Titmus Stereo test. Statistical analysis revealed a significant relationship between the sensory status and the duration of strabismus (P=.00002), the age at surgery (P=.00289), and postoperative ocular alignment (P=.02211).

CONCLUSION

Early surgical and optical ocular alignment of strabismic patients is advisable to achieve fusion and stereopsis.

Disruption and reacquisition of binocular vision in childhood and in adulthood

PURPOSE OF REVIEW

This article reviews the most recent studies that address the loss of and restoration of binocular vision in childhood and adulthood and summarizes recent changes in treatment approaches.

RECENT FINDINGS

Studies during the last two years support the idea of continued plasticity of the binocular visual system throughout life. Children and adults with strabismus onset following binocular vision maturation are susceptibility to a permanent disruption of stereopsis and sensory fusion. Plasticity of the binocular visual system, however, also means continued restorability of function. Despite a rather short critical time interval for restoration of normal function (three months in children and 12 months in adults), peripheral or extramacular binocular visual function can be restored in most patients whose onset of disruption follows binocular maturation.

SUMMARY

Stereoacuity loss can occur in the visually mature patient who develops strabismus later in life and delay of treatment can be deleterious to the restoration of normal macular binocular vision. However, despite any delay of treatment, most patients with strabismus acquired following binocular vision maturation will manifest some stereoacuity or sensory fusion following eye realignment. These findings suggest all patients with strabismus need to have their eyes aligned, either surgically or optically, to maximize their binocular vision outcome.

The management of strabismus in adults--III. The effects on disability

INTRODUCTION

This is the third article in a series on the various facets of the management of strabismus in adults. Here, we give a broad overview of the types and severity of disability and provide initial validation of an instrument (questionnaire) to assess these disability aspects.

METHODS

After undergoing strabismus surgery, 101 patients from 6 centers completed a 6-item questionnaire in which they rated both the before-surgery and after-surgery severity of problems associated with their strabismus, ranging from specific health, daily functioning, social interaction, concerns about the future, and self-image to job-related difficulties.

RESULTS

The before-surgery outcomes showed significant variation across the 6 types of problems (P < 0.001), with "specific health" and "daily tasks" yielding the highest problem rating. Patients with diplopia reported more severe problems with "daily tasks" (P = 0.004) and "concerns about the future" (P = 0.026) than patients without diplopia. Overall, all problem ratings declined after surgery (P < 0.001), but patients who were not successfully aligned were left with higher problem ratings on "specific health" (P = 0.005), "daily tasks" (P = 0.003), and "social interaction" (P = 0.024).

CONCLUSIONS

The results indicate a wide range of disability aspects in adult patients with strabismus, with moderate differences between patients with or without diplopia. Improvements in disability after surgery, as reflected by these ratings, should be taken into account when assessing the health value of adult strabismus management.

The management of strabismus in adults--II. Patient and provider perspectives on the severity of adult strabismus and on outcome contributors

PURPOSE

As part of a larger study intended to evaluate the management of strabismus in adults, we documented and compared patient and provider perspectives on the various factors that may contribute to treatment outcome and value of strabismus care.

METHODS

By completing a questionnaire, 170 patients with strabismus (ages 19 to 87 years) and 11 strabismus specialists who performed surgery on these patients each indicated the relative weight of several disease- and treatment-related contributors to the outcome and value of care. In addition, each respondent rated the severity of the strabismus before and after surgery.

RESULTS

Overall severity ratings improved as a result of surgery. The improvement perceived by the physicians was 5.1 +/- 1.7 on a 10-point scale and was larger than the 2.6 +/- 3.6 points improvement perceived by the patients ( P < 0.001). Patients and physicians expressed different views on the relative contributions to outcome and value (overall P < 0.001). Both groups indicated "the condition," "the physician," and "the procedures" as the largest contributors, but "condition" was perceived as more important by the physicians than by the patients ( P < 0.001), and "physician" was more important to the patients than to the physicians ( P < 0.001).

CONCLUSION

Although in approximate agreement on the main contributors to outcome and value, discrepancies exist between perspectives of patients and physicians on the relative weights of those contributors. Public information, education, and counseling may bring these perspectives better in line and ultimately improve both quality and patient satisfaction.

Factors influencing stereoacuity outcomes in adults with acquired strabismus

PURPOSE

Functional improvements of binocular vision after strabismus surgery in adults are common but not well understood. In a prospective study, factors associated with stereoacuity outcome in patients with strabismus acquired following binocular vision maturation were investigated.

DESIGN

Prospective data collection.

METHODS

Twenty-three patients aged 14 to 85 years with acquired strabismus were enrolled. Random dot stereoacuity was quantified using a battery of tests including the Randot Preschool Stereoacuity test, the Randot (version 2) shapes test, and the Randot Butterfly test.

RESULTS

Ninety-six percent of patients achieved measurable stereoacuity following successful eye realignment. Better median stereoacuity is achieved in patients with the following characteristics: < or =12 months of constant strabismus (60 vs 400 seconds of arc with >12 months' strabismus, P < .001); a presurgical capacity for fine to moderate stereopsis (60 vs 400 seconds of arc with coarse or no measurable stereopsis, P < .005); a presurgical capacity for macular fusion (60 vs 400 seconds of arc with no measurable macular fusion capacity, P < .001); and postsurgical orthotropia (100 seconds of arc) or intermittent orthotropia (100 seconds of arc vs 2000 seconds of arc with 5 to 8 prism diopters (PD) of postsurgical residual strabismus, P < .05).

CONCLUSION

Surgical correction of acquired strabismus is associated with recovery of stereopsis. Factors associated with stereoacuity outcomes include duration of strabismus and presurgical binocular vision capacity. A postsurgical correction of orthotropia or intermittent orthotropia supports better stereoacuity than a larger residual angle of strabismus subtending up to 8 PD of deviation.

Predictive factors underlying the restoration of macular binocular vision in adults with acquired strabismus

PURPOSE

To investigate whether macular binocular vision can be permanently lost following acquired strabismus and to identify predictive factors underlying its restoration.

SUBJECTS AND METHODS

Twenty-three patients with strabismus acquired after binocular vision maturation were enrolled. Factors studied included duration of eye misalignment, age at treatment, pre-surgical strabismus type, pre-surgical diplopia, and pre-surgical capacity for binocularity. The restoration of macular binocular vision was evaluated between 1 and 3 years following successful eye re-alignment and was defined as 60 seconds of arc stereopsis or better on the Titmus circles and/or the Preschool Randot Stereoacuity test.

RESULTS

Sixteen of 23 (70%) or 7/23 (30%) of patients achieved macular binocular vision following successful surgical eye realignment using the Titmus circles versus the Preschool Randot Stereoacuity test. Patients with < or =12 months constant eye misalignment were more likely to achieve macular binocular vision following treatment than patients with >12 months constant eye misalignment.

CONCLUSIONS

Macular binocular vision continues to be susceptible to permanent loss in adult patients. Factors that are predictive of the restoration of macular binocular vision include duration of constant eye misalignment and the pre-surgical capacity for binocularity.

Binocularity following surgical correction of strabismus in adults

PURPOSE

This is a retrospective study to determine the pre- and postoperative binocular status of adults who have undergone surgical correction of strabismus.

METHODS

A list of all consecutive adult patients who underwent surgery for strabismus between June 1990 and December 2001 (surgery by MBM) was compiled and their medical charts were reviewed. Patients who had at least 6 weeks postoperative follow-up were included if their charts were available for review and if information on binocularity was recorded. Binocularity was measured by the Titmus stereo test (Stereo Optical Co., Inc., Chicago), and/or the Worth 4-Dot test for distance (Scioto Medical Products, Powell, OH [discontinued]), and/or the Worth 4-Dot near test (Gulden Ophthalmics, Inc., Elkin Park, PA). Improvements or decreases in stereo acuity were noted 6 weeks postoperatively and at the final office visit. Prism management was incorporated pre- and/or postoperatively in some of our patients. A total of 112 patients underwent surgery for strabismus. Of these, 72 patients, aged 16 to 80 years, were included; 24 were excluded as their charts did not contain any information on stereo acuity 6 weeks postoperatively or were lost to follow-up after surgery, and 16 were excluded because their charts were unavailable from storage.

RESULTS

The mean follow-up for the study patients was 16.5 months (range 6 weeks to 79 months). Overall, 30 of the 72 patients improved in binocular function (42%), 38 remained the same (53%), and 4 decreased (5%). If you exclude those patients with 40 sec of stereo acuity preoperatively whose stereopsis, by definition, could not improve further, and look only at the 59 surgical patients who could improve, then 51% improved. A variety of surgical procedures was performed, the most common being a bilateral medial rectus recession. Eleven patients required a second surgical procedure and two required a third surgical procedure.

CONCLUSION

The benefits of surgical correction of strabismus in adults include improvement in binocular function as seen in 51% of the patients in the study.

The management of strabismus in adults--I. Clinical characteristics and treatment

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 < 9 years) or after (AVM, or age >/= 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.

Postoperative stereoacuity following realignment for chronic acquired strabismus in adults

BACKGROUND

There is controversy regarding whether or not visually mature individuals can permanently lose stereoacuity and under what conditions stereoacuity can be regained. Some have proposed a critical duration of misalignment in adults beyond which recovery of fine stereoacuity is not possible, despite successful surgical alignment.

METHODS

Twenty-one adult patients (median age 59 years) with large-angle acquired strabismus and who were successfully surgically aligned after 7 to 501 months of misalignment were studied. Subjects had no evidence of motor or sensory fusion since the onset of strabismus, on preoperative exam, or by history. Stereoacuity was measured using 1 or more of the Frisby, Preschool Randot and Titmus tests, at 8 weeks and at 12 months. Data from tests with monocular clues were not used.

RESULTS

At total of 67% of patients with chronic acquired strabismus and no preoperative fusion regained measurable stereoacuity and 44% regained fine stereoacuity of at least 60 seconds of arc. Of 10 patients with no or subnormal stereoacuity 8 weeks postoperatively, 6 (60%) showed improvement at the 12-month visit. Misalignment for up to 4 years did not preclude the development of postoperative stereoacuity.

CONCLUSIONS

Although a minority of adult strabismus patients may permanently lose stereoacuity despite successful alignment for acquired strabismus, the majority do show recovery. Such recovery of stereoacuity may take several months to occur. In our adult series, duration of misalignment did not predict failure to recover stereoacuity.

The value of adult strabismus correction to the patient

OBJECTIVES

To look at the value of adult strabismus correction to the patient, to consider what is known, and to define the challenges and opportunities for helping these patients.

METHOD

The benefits of adult strabismus correction leading to the establishment of binocularity, expansion of visual field, and improved psychosocial health are presented and supported by published studies.

RESULTS

Adults with strabismus can benefit from its correction.

CONCLUSION

There is a tremendous need to educate the medical community and the lay public that adults with strabismus can be helped with restoration of their eyes to a position of alignment for normal function.

The negative psychosocial impact of strabismus in adults

INTRODUCTION

The goal in the treatment of strabismus is to realign the visual axes to eliminate diplopia, produce or restore binocular vision, expand the binocular visual field, and/or provide a normal appearance. The treatment of strabismus in adults who do not experience diplopia or who do not have binocular potential has sometimes been regarded as "cosmetic." Many adults with strabismus have stated that it has had a negative effect on their lives. This study was designed to ascertain whether there is a negative social bias against adult patients with strabismus that could affect interpersonal relationships and limit employment opportunities.

METHODS

An orthotropic person was photographed in primary, right, and left gaze. These photographs were then digitally altered to produce an esotropia and exotropia of similar magnitude. Subjects were then asked to evaluate a single photograph with reference to personality characteristics that are important for social interaction and employment capability.

RESULTS

Overall, the strabismic faces were judged significantly more negatively, across 11 descriptive characteristics, than the nonstrabismic face. The effect of esotropia was worse than exotropia.

CONCLUSION

Strabismus creates a significant negative social prejudice. These biases can have a detrimental impact on socialization and employability. Treatment of strabismus may positively alter perceived characteristics of individuals and improve their ability to socialize normally and obtain employment. Therefore, the treatment of strabismus should not be considered cosmetic even when there is no hope of improving binocular vision.

Clinical characteristics of surgically treated adult strabismus

BACKGROUND

Strabismus is present in approximately 4% of the population with most forms becoming clinically evident in infancy and childhood. Adult strabismus, including that resulting from recurrent childhood deviations, varies in etiology, presentation, symptomatology, and response to treatment. This report is intended to prospectively characterize adults who required surgical correction of their strabismic deviation.

METHODS

Beginning in 1991, a prospective computerized database was collected that contained all clinical, laboratory, and surgical information on the adult ocular motility service at the Scheie Eye Institute and The Children's Hospital of Philadelphia (Philadelphia, Pa). Analysis of those patients who underwent surgical correction of their strabismus is included in this report. Demography, clinical characteristics, and surgical procedures including results were analyzed separately in adults with their strabismus beginning before visual maturation (BVM) (9 years of age) and after visual maturation (AVM).

RESULTS

A minimum of 6 months and average of 1.8 years follow up is reported on 262 procedures in 255 patients with an average age of 37 between January 1991 and January 1996. Sixty-two percent of patients had their strabismus onset BVM. Fifty-one percent of BVM patients and 80% of AVM patients had incomitant deviations. Adjustable suture surgery was performed on 97% of all patients, with 28% of BVM and 57% of AVM patients having multiplanar surgery. Successful motor alignment was achieved in 85% of all patients after one surgical procedure. Sensory success was achieved in 81% of all AVM patients and 25% of all BVM patients. Subjective success was 94% in both groups of patients.

CONCLUSIONS

Numerous differences exist between childhood and adult strabismus characteristics and response to surgery. Although strabismus surgery is effective, differences in results reflect the varied physiology regarding etiology, pathophysiology, and symptomology. Classification into AVM and BVM groups will provide continued clarity for future studies.

Strabismus surgery among aged medicare beneficiaries

OBJECTIVES

The purpose of this study was to investigate the incidence of strabismus surgery among aged patients in the United States.

METHODS

The Medicare Part B claims experience (physician professional fee billing) for 1995 was reviewed for the number of times each strabismus surgical procedure recognized in Physicians' Current Procedural Terminology (CPT) was performed. To determine the indications for the procedures that were performed, a 5% sample of claims was reviewed for the pertinent International Classification of Diseases, Ninth Revision, Clinical Modification, diagnostic codes.

RESULTS

There were 27 million aged Medicare beneficiaries eligible for Part B benefits in 1995 in a fee-for-service setting. During that year physicians reported 9497 strabismus physician services. These represented 6585 separate procedures (CPT codes 67311 to 67343) and 277 botulinum toxin (Botox) injections for strabismus (CPT 67345) performed during 1995. Sixty-nine percent of the surgical procedures were for horizontal correction and 28% were for vertical correction. Adjustable sutures were used for only 1240 cases (1 9%). The add-on procedural code for reoperation surgery or surgery in the presence of restriction of the extraocular muscles was used in just 930 cases (14%). The most common diagnosis for horizontal surgery was exotropia. Paralytic strabismus and thyroid disease were identified for 17% of cases. Three percent of the diagnoses were inappropriate for the procedures performed and may have been reported in error.

CONCLUSIONS

These data confirm a very low incidence of strabismus surgical procedures (2/10,000) and injections (1/100,000) among aged Medicare beneficiaries. The strabismus surgery was most often performed to repair a horizontal deviation. The adjustable suture technique was used infrequently. These data may be extrapolated into the future to aid in determining the strabismus services that will be needed early in the next century.