Lateral Recession Research Articles

Surgical outcomes related to degree of unilateral lateral rectus muscle recession in intermittent exotropia of 20 prism diopters.

We compared the surgical results of different degrees of unilateral lateral rectus muscle recession (ULR) and investigated the surgical outcomes and factors related to recurrence of intermittent exotropia of 20 prism diopters (PD). Retrospective study. The study comprised 163 patients with intermittent exotropia of 20 PD who underwent ULR between January 2010 and May 2015 and at least 2years of follow-up after the initial surgery. The patients were divided into 3 groups according to the extent of ULR (8.0, 8.5, or 9.0mm), and the surgical results were compared. We investigated the surgical outcomes and factors related to recurrence. The mean postoperative follow-up period was 3.89 ± 1.82years. The rate of recurrence within 2years differed clinically (8.0mm: 25.7%; 8.5mm: 19.0%; 9.0mm: 8.6%). However, other factors did not significantly differ among the groups. The comparison of the recurrence and the nonrecurrence groups showed that the age at the time of surgery varied significantly (recurring: 6.5years, nonrecurring: 8years; P = 0.012). A younger age at the time of surgery and a ULR of 8.0mm were significant risk factors for the recurrence of ULR in intermittent exotropia of 20 PD. We suggest that a surgical dose of 9.0mm ULR is preferable to 8.0mm ULR for intermittent exotropia of 20 PD.

Long-term Motor and Sensory Outcomes After Unilateral Lateral Rectus Recession-Medial Rectus Resection for Basic Intermittent Exotropia.

To report long-term motor and sensory outcomes after unilateral lateral rectus recession-medial rectus resection for basic intermittent exotropia. The medical records of patients who had undergone unilateral lateral rectus recession-medial rectus resection for basic intermittent exotropia and were observed postoperatively for a minimum of 10 years were reviewed retrospectively. A total of 41 patients were included (mean age: 6.07 ± 2.96 years; range: 3 to 17 years). The mean postoperative follow-up was 13.28 ± 3.27 years (range: 10 to 23 years). Overall, 19 patients (46%) had surgical success at their most recent follow-up visit. Age at onset of strabismus, age at surgery, strabismus duration, preoperative size of near and distance deviation, presence of stereopsis, and initial postoperative overcorrection did not predict motor outcome after surgery. Twenty-five patients (74%) achieved stereopsis. None of the 4 patients without binocular single vision preoperatively achieved stereopsis, compared to 3 of 7 patients (43%) with peripheral binocular single vision (P = .02). Five of 7 patients (71%) with a preoperative stereoacuity of 120 to 240 seconds of arc improved to 60 seconds of arc. Age at surgery did not predict stereopsis. Patients with a strabismus duration of 5 years or less achieved a better stereopsis. Fewer than half of the patients with basic intermittent exotropia achieved a successful long-term surgical outcome. Age at surgery, strabismus duration, preoperative stereopsis, and an initial postoperative overcorrection did not predict motor outcome. A pre-operative absence of binocular single vision indicated a poor prognosis for stereopsis. A shorter duration of strabismus predicted a better stereopsis after surgery. [J Pediatr Ophthalmol Strabismus. 2020;57(5):326-332.].

Medial Rectus Advancement for Secondary Exotropia

To determine the preoperative characteristics and surgical results after medial rectus advancement in patients with secondary exotropia. Retrospective, interventional case series. Setting: Tertiary Care University Medical Center. PatientPopulation: 221 patients with a diagnosis of secondary exotropia who underwent medial rectus advancement surgery by a single surgeon. Preoperative demographics, exodeviation and motility, intraoperative findings, and postoperative results were recorded. MainOutcomeMeasure: Success of surgery, defined as Esotropia <15 prism diopters (pd) at postoperative week 1, or any deviation of <8 pd at postoperative month 2 (POM2). A total of 98 patients underwent unilateral medial rectus advancement (UMRadv), 89 underwent UMRadv with lateral rectus recession (LRc), and 34 underwent bilateral medial rectus advancement (BMRadv). POM2 success rates were 66.7% in UMRadv patients, 62.1% in UMRadv+ LRc, and 56% in BMRadv. A total of 117 patients had preoperative adduction deficits, which were significantly associated with the finding of an intraoperative stretched scar (P < .001). Larger preoperative duction deficits were associated with larger stretched scars (P < .001). At POM2, the mean effect of surgery (pd of correction/mm) was 2.3 ± 1.4 pd/mm for UMRadv, 2.5 ± 0.8 pd/mm for UMRadv+ LRc, and 2.8 ± 1.1 pd/mm for BMRadv. Patients with a stretched scar had significantly less correction per millimeter (2.2 ± 1.2 pd/mm) compared with those without (2.6 ± 1.2 pd/mm, P < .001). A total of 38.6% of patients experienced exodrift greater than 10 pd. Exodrift was significantly larger in the BMRadv group (P < .005). These results provide guidance for surgical correction based on preoperative deviation and ductions. Adduction deficits indicate a stretched scar, which must be treated with resection and advancement of the medial rectus. A larger amount of surgery is needed in patients with a stretched scar. Exodrift is common, and therefore aiming for approximately 10 pd of overcorrection at postoperative week 1 can improve final outcomes. Medial rectus advancement results in successful surgical results at POM2 for secondary exotropia.

Contralateral Surgery for the Treatment of Third Nerve Palsy with Aberrant Regeneration

To report the results of contralateral recession-resection of the horizontal muscles in oculomotor nerve palsy with aberrant regeneration to correct both the strabismus and the ptosis in one procedure. Retrospective case series. This is an institutional study on patients with oculomotor nerve palsy with aberrant innervation who had contralateral eye muscle surgery in 2 different centers. Patients were included if they have both exotropia and aberrant regeneration with a ptosis that improved on adduction. All patients had contralateral lateral rectus recession and medial rectus resection. Ductions, versions, angle of misalignment, and degree of ptosis were evaluated before surgery and at last follow-up. Eleven patients were identified. The mean age at surgery was 15.0 ± 9.2 years. Five patients were male (45%). Trauma was the cause in 8 (72%) cases. The mean angle of exotropia was 42 ± 14 prism diopters. The mean degree of ptosis was 3.9 ± 1.6mm. The mean lateral rectus recession was 8.2 ± 1.1mm, and the mean medial rectus muscle resection was 6.7 ± 0.9mm. The mean follow-up was 6.4 ± 2.5months. After surgery, none of the patients had residual exotropia >10 prism diopters. The mean degree of ptosis after surgery was 0.9 ± 0.8mm. None of the patients required further surgery for ptosis or strabismus. Contralateral eye muscle in third nerve palsy with aberrant innervation offers the advantage of simultaneous correction of both strabismus and ptosis through a single procedure.

Slanted bilateral lateral rectus recession for convergence insufficiency-type intermittent exotropia: a retrospective study

BackgroundThe present study sought to investigate the efficiency and safety of slanted bilateral lateral rectus recession for the treatment of convergence insufficiency-type intermittent exotropia.MethodsThis retrospective study included 34 patients who underwent slanted bilateral lateral rectus recession for convergence insufficiency-type intermittent exotropia in Shandong Provincial Hospital affiliated to Shandong First Medical University between September 2013 and October 2015 with a minimum follow-up of 6 months. A successful surgical alignment was defined as + 5 (positive for esotropia) to − 10 (negative for exotropia) prism diopters (PD) of orthotropia in the primary position while viewing distant or near targets and a near-distance deviation difference ≤ 8PD.ResultsThe mean age of the patients at surgery was 7.09 ± 3.80 years (range, 3 to 18 years). The mean distance deviations were − 26.09 ± 6.5 PD (range, − 15 to − 35 PD) and the mean near deviations, − 37.21 ± 6.3 PD (range, − 25 to − 45 PD) preoperatively. The mean recession amount of upper pole of the lateral rectus was 5.97 mm (range, 4.0 to 7.5 mm) and that of lower pole of the lateral rectus, 7.49 mm (range, 6.0 to 8.5 mm). At a mean follow-up of 15.0 months (range, 6 to 37 months), the surgical success rate was 70.6% (24/34), the under-correction rate was 17.6% (6/34), and the overcorrection rate was 11.8% (4/34). The mean near-distance deviation difference was significantly reduced from 11.12 ± 2.06 PD (range, 10 to 15 PD) preoperatively to 2.47 ± 3.04 PD (range, 0 to 10 PD) postoperatively (P < 0.001). Each millimeter of difference between the upper and lower poles of the lateral rectus recession was associated with an improvement of 5.65 PD in the near-distance deviation difference. At the final follow up, a near-distance deviation difference of ≤8PD was found in 32 (94.1%) patients. None of the patients developed A-V pattern, torsional diplopia, or restricted abduction of the eyes.ConclusionsSlanted bilateral lateral rectus recession may successfully reduce the distance and near exodeviations and the near-distance deviation difference, thus was proved to be an effective and safe procedure for the treatment of convergence insufficiency-type intermittent exotropia.

Unilateral recession and resection surgery with adjustable suture in adult sensory exotropia: long-term success and exotropic drift

ABSTRACT This retro-prospective study aimed to evaluate the correlation between initial postoperative deviation and long-term outcome of unilateral recession and resection surgery with adjustable suture in adult sensory exotropia, factors associated with long-term outcome, exotropic drift, and time to failure following surgery. We included adult patients (age ≥18 years) with sensory exotropia who underwent unilateral lateral rectus recession with adjustable suture and medial rectus resection with at least 2-year follow-up. Preoperative and postoperative data was collected. Either Krimsky or alternate and prism cover testing was used to measure the angle of deviation depending on patients’ fixation ability. Glasses with full refractive correction were worn if they can provide better visual acuity. Exodeviation at near fixation was used in statistical analysis. A total of 38 patients (mean age at surgery 32 ± 13 years) were included. Median preoperative exotropia was 45 PD (IQR 40–55, range 25–70) and median initial postoperative deviation was esotropia 8 PD (IQR 0–11, range from exotropia 8 to esotropia 30). Mean follow-up time was 5 ± 2.5 years (range 2–10). Motor success, defined as a deviation within 10 PD of orthotropia, was found in 50% and 42% of patients at 2-year and last follow-up. Initial postoperative deviation and amount of lateral rectus recession were significantly associated with long-term outcome (p = .006 and 0.029). Patients with initial moderate and minimal overcorrection had higher success rates (67% and 62%) than patients with initial orthotropia or undercorrection (10%) (p = .002). Median overall rate of exotropic drift was 8 PD/year (IQR 6–13, range from esotropic drift 8 to exotropic drift 26). Time to failure in nonsuccess group was 24 months (IQR 21–24, range 2–24). In conclusion, unilateral recession and resection surgery with adjustable suture in adult sensory exotropia achieved 50% success at 2 years. Initial postoperative moderate overcorrection results provide the highest chance for long-term success. The majority of patients developed exotropic drift with time and time to failure was 2 years.

Risk factors for excessive postoperative exo-drift after unilateral lateral rectus muscle recession and medial rectus muscle resection for intermittent exotropia

BackgroundTo detect significant factors associated with excessive postoperative exo-drift in young patients with intermittent exotropia who had undergone unilateral lateral rectus muscle recession and medial rectus muscle resection.MethodsWe retrospectively examined the records of 64 consecutive patients < 18 years old who underwent surgery between April 2004 and December 2011. We sought risk factors for excessive postoperative exo-drift among patients’ demographic and clinical characteristics using univariate and multivariable linear regression analysis.ResultsYounger patients (P = 0.007), and those with larger preoperative exo-deviation at distance (P = 0.033), a lower incidence of peripheral fusion at distance (P = 0.021) or a greater postoperative initial eso-deviation (P = 0.001), were significantly more likely to have an excessive postoperative exo-drift (> 20 prism diopters). Univariate analysis revealed significant associations between excessive postoperative exo-drift and age at surgery (P = 0.004), preoperative exo-deviation at distance (P = 0.017) and postoperative initial eso-deviation at distance (P < 0.001). Multivariable linear regression analysis showed that postoperative initial eso-deviation at distance (P = 0.008) was significantly associated with postoperative exo-drift.ConclusionsPostoperative exodrift in unilateral RR is predicted by the initial postoperative eso-deviation, which may offset the overcorrection. However, the exo-drift is greater in cases with a large preoperative exo-deviation and/or at a younger age, and should be followed carefully.

Long-term results of augmented unilateral lateral rectus muscle recession for dissociated horizontal deviation.

We report the long-term surgical results of augmented lateral rectus muscle (LR) recession for dissociated horizontal deviation (DHD) without concomitant exotropia (XT) or esotropia (ET). This retrospective review included patients with DHD without XT or ET who underwent augmented LR recession and were followed-up for ≥12 months. Each patient’s medical records were evaluated to identify their demographics, preoperative angle of deviation, surgical procedure, success rate, and reoperation rate. A total of 11 patients with DHD were included (median patient age at surgery, 6 years; interquartile range [IQR], 5 to 10 years). Four patients (36.4%) had a history of infantile ET while three patients (27.3%) had a history of unilateral cataract surgery for congenital cataract. The median preoperative angle of DHD in the unilateral eye was 20 prism diopters (PD) (IQR, 15 to 25 PD). The median amount of LR recession was 8.0 mm (IQR, 7.5 to 8.0 mm). Three patients (27.3%) underwent simultaneous surgery for dissociated vertical deviation. At the final examination after a median follow-up period of 32 months (IQR, 24 to 58 months), 10 patients (91%) showed successful alignment. The long-term successful alignment rate after augmented LR recession for DHD was good; thus, application of this technique is appropriate in patients with DHD.

Surgical outcome of patients with unilateral exotropic Duane retraction syndrome

To describe the clinical features and surgical outcomes of patients with unilateral exotropic Duane retraction syndrome (DRS). The medical records of patients with unilateral exotropic DRS who underwent surgery between March 2015 and February 2018 were reviewed retrospectively. A total of 40 patients (mean age, 18.75±12.54years; 21 males [53%]) were included. In 28 patients (70%) the left eye was involved. All patients had globe retraction and head turn toward the opposite side of the affected eye. Remarkable upshoot/downshoot movement was detectable in 11 patients (28%). The mean deviation for near and distance improved from 24.37Δ ± 12.34Δ (range, 6Δ-77Δ) and 19.67Δ±10.76Δ (range, 4Δ-60Δ) to 4.25Δ±8.61Δ (range, 0Δ-50Δ) and 2.62Δ±6.15Δ (range, 0Δ-35Δ) after the first surgery (P <0.001 for near and far deviation). Mean postoperative follow-up was 7.82±9.45months. Two patients required reoperation. Different types of surgeries, including lateral rectus recession (with or without Y-splitting), lateral and medial rectus recession (with or without Y-splitting of the lateral rectus muscle), bilateral lateral rectus recession, and lateral rectus recession with vertical rectus nasal transposition were performed. Twenty-four patients (60%) were successfully treated with only a single recession of the ipsilateral lateral rectus muscle. The mean lateral rectus recession was 7.45±0.73mm (range, 6-8.5mm), and the mean dose-response for lateral rectus recession was 2.79Δ±0.64Δ/mm for near and 2.45Δ±0.67Δ/mm for distance. Simple lateral rectus recession (with or without Y-splitting), even in the presence of significant deviation (through 35Δ), seems to be a successful procedure for management of patients with unilateral exotropic DRS.

Binocular discrepancy in lateral rectus muscle attachment in intermittent exotropia with eye dominance.

To determine whether there is asymmetry in the lateral rectus (LR) muscle attachment between both eyes in patients with intermittent exotropia (IXT) with a non-dominant eye, but without amblyopia or anisometropia. In total, 109 patients who underwent bilateral lateral rectus recession for IXT were included, 81 with and 28 without eye dominance. The limbus-insertion distance and tendon width of the LR muscle were measured intraoperatively using callipers. The insertion-equator distance (presumed arc of contact), area of contact (arc of contact × tendon width), and torque value (radius of globe × arc of contact) of the LR muscle were calculated based on intraoperative measurements and axial length measured using a partial interferometer. Parameters regarding LR muscle attachment were compared between fellow eyes and between groups. Mean measurements in all parameters related to LR muscle attachments other than tendon width were not different between the two eyes or between groups. The mean tendon width of the non-dominant eye was 9.2 ± 0.7mm, narrower than the 9.4 ± 0.5mm width in either eye of patients without dominance (p = 0.020). However, there was no difference in all parameters in 21 pairs of patients after matching. The proportion of patients who showed binocular discrepancies in attachment measurements beyond that attributable to potential measuring errors did not differ between the two groups. Structural parameters related to LR muscle attachments did not differ based on eye dominance, suggesting that the anatomic structure of LR muscle attachments is not responsible for eye dominance in IXT.

Changes of anterior segment parameters after horizontal rectus muscles recession versus resection

Background: To record the corneal, and anterior chamber depth changes after performing recession versus resection of horizontal recti muscles. Methods: Consecutive patients who underwent isolated lateral rectus muscle recession or resection February 2014 to January 2015 were prospectively studied. Refractive error (spherical equivalent); K1, K2, and mean k reading, anterior and posterior corneal elevation; and anterior chamber depth were measured (Pentacam) before, 1 month, and 3 months after surgery. Patients who could not maintain reliable fixation and those with a history of eye surgery were excluded. Pre- and postoperative measurements were compared by analysis of variance. Results: A total of 36 eyes of 23 patients (average age, 16 years) were included. Rectus muscle recession was performed in 24 eyes; and resection was performed in 12 eyes. Statistically significant changes in mean keratometry of recession group only. Central anterior elevation, and central anterior chamber depth were significant when both groups are compared at first month after surgery. Changes became regressive at the end of the third month. Although a significant change of central anterior elevation persisted. Conclusions: In recession group, the mean K was the only statistically significant variable by the first postoperative month. Comparing the both groups, the anterior corneal elevation, and central anterior chamber depth revealed a significant difference by the end of the first postoperative month. After 3 months, all parameters showed a statistical insignificant difference between the recession and resection groups except the anterior corneal elevation.

Surgical outcomes of plication versus resection in basic type of intermittent exotropia

ObjectivesTo compare the surgical outcomes of plication versus resection in basic type of intermittent exotropia. DesignProspective interventional study. Participants60 patients above 6 years of age with diagnosis of basic type of intermittent exotropia. MethodsA randomized study was conducted in 60 patients above 6 years of age with diagnosis of basic type of intermittent exotropia. They were equally divided in two groups by computer generated random number table. Group A underwent recession and plication (RP) and group B underwent recession and resection (RR) based on post patch deviation with constant 8 mm lateral rectus recession in both groups. Parameters assessed were postoperative alignment, cosmetic outcome, improvement in binocularity & stereoacuity and dose effect. Successful outcome was defined as post patch deviation ≤ 10 Prism diopters (PD) of exophoria/exotropia to < 5 PD of esophoria/esotropia at 12 months follow up. ResultsThe mean preoperative and postoperative deviation was 44.67 ± 4.5 PD and 10.13 ± 3.6 PD respectively in group A and 43.17 ± 4.8 PD and 9.40 ± 3.3 PD respectively in group B (p = 0.423). The exodrift at 12 months follow up was 4.4 ± 2.8 PD in group A and 4.67 ± 3.29 PD in group B. There was statistically no significant difference in outcomes between the two groups. Mean effect of MR plication at last follow up was 5.91 PD/mm and MR resection was 5.5 PD/mm (p = 0.877). ConclusionBoth procedures achieved acceptable ocular alignment and had a comparable dose effect. Plication has certain added advantages over resection hence may be preferred as an alternate tightening procedure.

Changes of Corneal Topographic Measurements and Refractive Errors after Horizontal Muscle Surgery. A Case Series

Abstract Background: Refractive and corneal topographic changes after routine strabismus surgery have been reported and can occur even after a successful surgery. Study aims to evaluate the effect of horizontal muscle surgery on refractive errors and corneal measurements. Patients and methods: This study includes 25 eyes of 22 patients who have manifest strabismus. The patients were divided into two groups. Group A (10 eyes of 7 patients) subjected to unilateral lateral rectus recession. Group B (15 eyes of 15 patients) all of them subjected to lateral rectus recession and medial rectus resection in the same eye. Cycloplegic automated refraction (including spherical equivalent, astigmatic error and astigmatic axis) were recorded preoperatively, one month and 3 months after surgery. Corneal topography including flat K, steep K were recorded preoperatively, one month and 3 months after surgery. Results: A significant change of spherical equivalent towards myopic shift after horizontal rectus muscle recession was observed (P=0.000). A significant change of refractive cylindrical power with rule was found in both groups (P=0.000). Corneal topographic parameter (flat k) showed a significant change in the both groups (P=0.000). . These changes persisted till the last postoperative visit. Conclusion: Horizontal muscle surgery induced a statistically significant change of astigmatism power that persists till the 3rd. postoperative month. A significant change of spherical equivalent was found in the postoperative period after horizontal strabismus surgery only in recession group.

The stability of horizontal ocular alignment of triad exotropia after one-step triple surgery.

A-pattern exotropia, superior oblique muscle overaction, and dissociated vertical deviation may coexist and are referred to as triad exotropia. The present study evaluated the postoperative stability of horizontal ocular alignment of triad exotropia and possible prognostic factors. Medical records of patients with triad exotropia who had one-step triple surgery of superior oblique muscle weakening, superior rectus muscle recession, and lateral rectus muscle recession were reviewed. The horizontal alignment and postoperative drift of triad exotropia were analyzed and compared with constant exotropia. The triad exotropia showed a mean of 7.7△ (± 8.5△) eso-drift, while the constant exotropia was (3.5△ ± 3.4△) exo-drift. Multiple linear regression analysis showed that the degree of superior oblique muscle overaction after surgery (P = 0.011) was the only factor associated with horizontal drift. Patients with superior oblique muscle underaction showed larger eso-drift when compared to patients without superior oblique muscle underaction (- 18.0△ ± 11.1△ vs. - 5.1△ ± 5.7△; P = 0.024). The final success rates of the triad exotropia and constant exotropia groups were 53.3% and 69.2%, respectively, and the overcorrection rates were 26.7% and 2.6% (P = 0.035). An overall trend of eso-drift in primary position occurred in triad exotropia after triple surgery up to a follow-up of 25months. Patients presenting superior oblique muscle underaction after surgery seemed to have large angles of eso-drift, which might be taken into account in surgical planning and follow-up.

Changes in the Effects of Bilateral Lateral Rectus Muscle Recession According to Preoperative Angle Deviation

Changes in the Effects of Bilateral Lateral Rectus Muscle Recession According to Preoperative Angle Deviation

Recurrence of Intermittent Exotropia after Bilateral Lateral Rectus Recession.

PURPOSE:The purpose of this study was to evaluate predictive factors for intermittent exotropia (XT) recurrence after bilateral lateral rectus (BLR) recession.METHODS:This is a retrospective chart review of patients with XT who underwent BLR recession surgery between January 2007 and March 2017 with at least one postsurgical follow-up. Forty-one medical records were reviewed. Information collected included age, gender, systemic diseases, history of prematurity, family history of eye diseases, visual acuity, refraction, ocular alignment and control, stereoacuity, slit-lamp examination, fundoscopy, and amount of BLR recession. Successful alignment was defined as ≤8 prism diopters of esotropia or exotropia postoperatively.RESULTS:The mean age of patients at the time of surgery and follow-up time was 9.2 ± 12.3 years (y) and 23.6 ± 36.5 months (m), respectively. The mean amount of BLR recession was 6.5 ± 1.0 mm. Recurrence rate was 43.9% on the last follow-up. Age at surgery and at the time of last follow-up were significantly higher in the recurring group (P = 0.04 and P = 0.05, respectively). Postoperative angle of misalignment during the first 3 months was correlated with exotropia recurrence. No statistical significance was found among the remaining factors studied.CONCLUSIONS:The recurrence rate of XT in our study was 43.9%; it was increased in patients operated at older age and amid those with significant exotropia detected in the early postoperative period (within 3 months of surgery).

Comparative study of unilateral lateral rectus hang-back recession versus bilateral rectus hang-back recession for management of small-angle basic intermittent exotropia in Egyptians children

Comparative study of unilateral lateral rectus hang-back recession versus bilateral rectus hang-back recession for management of small-angle basic intermittent exotropia in Egyptians children

Clinical Manifestations of Delayed-onset Consecutive Esotropia after Surgical Correction of Intermittent Exotropia.

PurposeTo evaluate the clinical features and prognosis of a delayed-onset consecutive esotropia (ET) after surgical correction of intermittent exotropia.MethodsThirty-four patients who developed consecutive ET after primary bilateral lateral rectus recession for the surgical correction of intermittent exotropia were evaluated retrospectively and were divided into two groups: delayed-onset consecutive ET group and the continuous consecutive ET group. Patients who developed esodeviation after once recovering to orthotropia within 1 month after the operation were included in the delayed-onset consecutive ET group, and patients with continuous esodeviation after the operation were included in the continuous consecutive ET group. We evaluated preoperative and postoperative angle of deviation, suppression, stereopsis, and follow up periods between the two groups and compared re-operation and success following non-surgical treatment between the continuous consecutive ET group and the delayed-onset consecutive ET group.ResultsAmong 34 patients with consecutive ET, 27 patients (79.4%) were included in the delayed-onset consecutive ET group, and seven patients (23.3%) were included in the continuous group. Success rate of non-surgical treatment was not statistically significant between two groups (p = 0.55), but it was higher in the delayed-onset group with 37.5%, and 25% of patients in continuous group were successfully recovered to straight alignment. Duration of orthotropia in delayed-onset group was 7.4 ± 6.0 months (range, 2–29 months). Age, sex, preoperative refractive error, preoperative exodeviation, suppression, and near steroacuity were not statistically significant between two groups (p > 0.05, all). In the delayed-onset group, three patients (11.1%) underwent re-operation, while three patients (42.9%) in continuous consecutive ET group underwent re-operation (p = 0.048).ConclusionsRe-operation rate of delayed-onset consecutive ET after surgical correction of intermittent exotropia was lower than that of continuous consecutive ET.

Resident Perspectives

Resident Perspectives

Comparison of contrast sensitivity based on the surgical results for intermittent exotropia.

To compare contrast sensitivity (CS) based on the surgical results for intermittent exotropia (IXT) and to examine the relationship between CS and photophobia. Medical records of the patients who underwent bilateral lateral rectus muscle recession for IXT between 4 and 12 years old were reviewed retrospectively. They were categorized based on the surgical results; successful correction group (n=36) and overcorrection group (esotropia ≥10 PD at 3mo postoperatively, n=18). Using CGT-2000 test for CS was performed binocularly, and subjective reports of photophobia was investigated preoperatively and at 3mo postoperatively. Objective photophobia was defined as a significant decrease in CS in the presence of glare. Preoperatively, there was no difference in CS between the groups. Postoperatively, under mesopic conditions, significant improvement of CS was observed at 6.3°, 4°, and 2.5° in the successful correction group and at 6.3° and 4° in the overcorrection group, regardless of glare. Under photopic conditions, at all visual angles except 0.64°, improvement in CS was noted in both groups while CS worsened significantly at 0.64° in the overcorrection group postoperatively. At all visual angles under photopic conditions postoperatively, regardless of glare, CS in the overcorrected group was significantly worse than that in the successful correction group, and CS was significantly decreased by addition of glare in both groups. All patients except one (96.4%) in the successful correction group and 8 patients (61.5%) in overcorrection group showed improvement of photophobia postoperatively, which correlated with CS under photopic conditions (P=0.001, 0.03). After surgery for IXT, CS under photopic conditions improve at all visual angles except 0.64°, while CS is significantly worse in the overcorrection group postoperatively at 0.64°. Subjective photophobia have significant correlation with CS under photopic conditions, and may be used as an objective indicator of photophobia.