Surgery For Consecutive Exotropia Research Articles

Strabismus Surgery of Consecutive Exotropia.

The purpose of this study was to determine the surgical outcome, dose-effect (DE), and degree of binocularity in patients undergoing surgery for consecutive exotropia following initial surgery of esotropia. Twenty-one patients were identified. We analyzed the mean angle of deviation pre- and postoperatively as measured with the alternate prism cover test, DE, and binocularity. All patients had had previous strabismus surgery. The surgery for consecutive exotropia had been performed at a mean age of 35.92 ± 18.26 years. In 19 of these patients, surgery of consecutive exotropia involved at least one previously operated extraocular muscle, and the mean interval to the previous surgery was 25.67 ± 16.14 years. The mean angle of deviation (DE) at distance and in the primary position was - 33.43 ± 12.75 prism diopters (PD) preoperatively, + 0.76 ± 7.91 PD 1 week after surgery, and - 7.24 ± 12.14 PD 3 months after surgery. The mean DE was 3.58 ± 1.53 mm/PD at 1 week and 2.70 ± 1.78 mm/PD at 3 months post-surgery. Postoperatively, 62% patients had a binocularity of at least Bagolini positive, 33% had either a positive TNO or Titmus Test, and 24% were Lang I positive (550″). Performing strabismus surgery with consecutive exotropia results in restoration of some binocularity in a large number of patients, even in adults, and should be considered as a possibility. The dose-effect is comparable to conventional surgery of exotropia.

Long-term surgical outcomes of patients with consecutive exotropia.

To evaluate the long-term surgical outcome of patients with consecutive exotropia. Patients who underwent surgery for the treatment of consecutive exotropia between January 2008 and July 2016 with a minimum follow-up period of 2years were retrospectively reviewed. Surgical outcomes were classified based on postoperative angle of deviation at 2years as follows: success (esodeviation ≤ 5 prism diopters [PD] to exodeviation ≤ 10 PD), and recurrence [exodeviation > 10 PD]). Postoperative angles of deviation at 1week, 1month, 6months, 1year, and 2years and at the final follow-up were investigated. A total of 37 patients (28 in the success group and 9 in the recurrence group) were included. Surgical success rate at 2years was 75.7%, and reoperation rate was 10.8% during a mean follow-up period of 42.4 ± 18.3months after consecutive exotropia surgery. After surgery, exodrift occurred mostly during 1-month follow-up in both groups, and those with no exodrift within 1month presented a higher surgical success. Thereafter, patients in the success group showed a more stable course during follow-up than those in the recurrence group. Stereopsis was an important factor associated with surgical outcome. Exodrift occurs mostly within 1month after surgery for consecutive exotropia. Targeting initial overcorrection and establishing esodeviation at postoperative month 1 is important to achieve successful results.

Factors associated with atypical postoperative drift following surgery for consecutive exotropia

To evaluate the associations of clinical and surgical factors with atypical postoperative drift following surgery for consecutive exotropia. A total of 66 patients with consecutive exotropia (≥10Δ at distance), after historical surgery for esotropia were retrospectively identified at a tertiary medical center. All patients underwent unilateral lateral rectus recession (on adjustable suture) with medial rectus advancement and/or resection. Immediate postoperative target angle was 4Δ-10Δ of esotropia at distance, anticipating mild postoperative exodrift. Actual postoperative drift was calculated as change in distance deviation from immediately postadjustment to 6weeks. Typical drift was defined as 0Δ-9Δ of exodrift. Excessive exodrift was defined as ≥10Δ. Esodrift was defined as 1Δ or more. Univariate and multiple logistic regression analyses were performed to evaluate for associations with a wide range of clinical and surgical factors. Overall there was a median exodrift (4Δ, quartiles 0Δ-10Δ). Of the 66 patients, 18 (27%) showed excessive exodrift; 15 (23%), esodrift. In multiple logistic analyses, larger preoperative distance exodeviation was associated with excessive exodrift (P=0.01), and non-normal medial rectus attachment status (abnormal [stretched scar, pseudo-tendon], attached to pulley, or behind pulley) was associated with esodrift (P=0.02). Approximately half of patients show atypical drift following unilateral surgery for consecutive exotropia, with larger preoperative distance exodeviation associated with exodrift and non-normal medial rectus muscle status with esodrift. Knowing these associations may help when counseling patients regarding surgical outcomes.

Intraoperative Findings in Consecutive Exotropia with and without Adduction Deficit

Consecutive exotropia may be associated with limited adduction, which has been reported to be caused by 1 or more anatomic abnormalities of rectus muscles or their insertions. We studied the relative frequency of grades of adduction deficit and the relative frequency of abnormal anatomic findings. Retrospective cohort study. Patients undergoing surgery for consecutive exotropia. Preoperative duction deficits were graded on a-5 (severe limitation) to 0 (normal) scale. Operative reports were reviewed to classify intraoperative factors: (1) medial rectus muscle attachment type (normal, abnormal [slipped or stretched scar], attached to pulley, behind pulley, or mixed [a tenuous normal attachment, but with muscle fibers also attached to the pulley or behind the pulley]), (2) medial rectus muscle distal fiber location (millimeters from original insertion), and (3) lateral rectus muscle tightness (normal, mild restriction, moderate restriction). Relationship of grade of adduction deficit to each intraoperative factor. Of 143 eyes, 124 (87%) had an adduction deficit. Eyes with abnormal (n= 23), pulley (n= 9), behind pulley (n= 8), or mixed (n= 7) attachments had worse adduction deficits than normal attachments (n= 96; P<0.02). There was a significant correlation between distal medial rectus muscle fiber location (0-19.5 mm recessed) and grade of adduction deficit (P < 0.0001). Eyes with mild or moderate lateral rectus muscle tightness on forced duction testing (n= 48/143 eyes) had worse adduction deficits than eyes without tightness (P < 0.001). Nevertheless, despite overall correlation, there was considerable individual variability. For example, for-1 and-2 adduction deficits, medial rectus muscle attachment could be at the pulley, behind the pulley, or include the pulley (19/87 eyes [22%]), and the lateral rectus muscle was tight in 36 of 87 eyes (41%). Adduction deficits are common in patients with consecutive exotropia. Overall, more severe preoperative adduction deficits are associated with medial rectus muscle insertion abnormalities and abnormal forced ductions, but frequently there are exceptions. Severe medial rectus muscle insertion abnormalities, including lost muscles, may be found despite mild preoperative adduction deficits.

Risk factors for consecutive exotropia after esotropia surgery.

To evaluate the risk factors in development of postoperative exotropia following bilateral medial rectus (BMR) recession for esotropia. 108 patients who underwent BMR recession for esotropia between November 1996 and July 2010 were enrolled. 54 patients who required surgery for consecutive exotropia were compared to 54 controls whose angle of deviation showed less than five prism diopters of esotropia at all periods after BMR recession. Amblyopia, dissociated vertical deviation (DVD), refractive error, inferior oblique overaction, and multiple surgery history were evaluated as risk factors for the development of consecutive exotropia. The postoperative changes of angle of deviation were calculated. Amblyopia was found in 27 patients (50.5%) in the exotropia group, and in six patients (11.1%) in the control group (P<0.001) before esotropia surgery. DVD was detected in 16 (29.06%) patients in the exotropia group as compared to 4 (7.4%) in the control group (P=0.003). With logistic regression analysis, the odds ratio of DVD was 5.27 (95% CI 1.63-17.03; P=0.006) and of amblyopia, 8.00 (95% CI 2.94-21.80; P<0.001). There were no significant differences between the two groups with regards to the pre-operative deviation, follow up periods, degree of hyperopia, presence of anisometropia or inferior oblique overaction, and history of multiple surgery. Using linear mixed model analysis, the exotropic shift across time was higher in the consecutive exotropia group relative to the controls (P<0.001). The presence of amblyopia before esotropia surgery and DVD correlated with risk of consecutive exotropia.

Classifying medial rectus muscle attachment in consecutive exotropia

To evaluate interexaminer agreement in classifying medial rectus muscle attachment in patients with consecutive exotropia. A series of intraoperative photographs of 26 eyes in 25 patients who underwent surgery for consecutive exotropia were retrospectively studied. Two examiners independently classified the medial rectus attachment as either normal, stretched scar, slipped muscle, or lost muscle. Agreement between examiners was evaluated using the weighted kappa (κ) statistic, and causes of disagreement were assessed. Agreement was found in 15 of 26 eyes (58%), signifying "moderate" agreement (κ=0.41). Approximately two-thirds of the disagreements, 7 of 11 eyes (64%), were between stretched scar and slipped muscle, with characteristics of each entity being present in the same muscle. The clinical distinction between stretched scar and slipped muscle appears to be obscure. We propose that they should be considered a single entity, which could be referred to as "abnormal scleral attachment."

Consecutive Exotropia after Convergent Strabismus Surgery—Surgical Treatment

Purpose: In this study the results of consecutive exotropia surgical treatment by using different surgical technics are presented. Methods: This study included 34 patients, aged 21 to 47 years (mean 27.9), who underwent medial rectus muscle advancement alone or in combination with medial rectus resection and/or lateral rectus recession. The mean interval between original surgery and surgery for consecutive exotropia was 8.5 years (range: 5.5 years to 14 years). Most of patients had 2 and more prior surgeries (73.5%) sold by an adduction deficit (47.06%). Results: The overall mean preoperative exodeviation was 35.12 ± 10.13 PD. Satisfactory alignment (within 10 PD of orthophoria) was achieved in 20 patients (58.8%) at 10 days after surgery and 24 patients (70.5%) at final 6-month follow-up. The most common surgical procedures were unilateral MR advancement and LR recession—47%. Conclusion: Medial rectus advancement is an effective method of surgical treatment, especially in cases with adduction limitation, but the risk of the eyelid fissure narrowing in cases of MRM advancement more than 5 mm associated with resection is present. In our opinion for reducing this risk in cases of XT with big angle of deviation, performing a smaller amount of advancement associated with recession of LRM can prevent the development of a such complication.

Midoperative Forced Duction Test as a Guide to Titrate the Surgery for Consecutive Exotropia

This is a retrospective study of the outcome of all consecutive exotropia surgery performed between the years 1999 and 2007. Excluded were cases of slipped muscles, muscle transpositions, and concurrent cyclovertical procedures. A total of 135 patients of mean age 40 years (range 6–72) were operated with a mean preoperative angle of deviation −40Δ (range −12 to −90). Five were treated with fixed sutures and the rest with adjustables. The surgery included preplanned lateral rectus recessions of mean 6 mm (range 2–9) and maximal possible medial rectus advancements with or without resections of mean 5.6 mm (range 2–11), intraoperatively adjusted to give a resistance of +1 to +2 for abduction on forced duction test (FDT). Adjustable suture patients were seen 4 to 6 hours after surgery and underwent further adjustment, if needed, to achieve the target angle. A further review took place at 2 weeks and 2 months. Children remained under follow-up till 8 years of age. Forty percent needed postoperative adjustment. The mean postoperative angle at final measurement was −2Δ (range +25 to −45). Eighty percent achieved an angle within 10Δ of orthotropia. No gross restrictions of ductions were present postoperatively.

Management of Nonresolving Consecutive Exotropia Following Botulinum Toxin Treatment of Childhood Esotropia

To study motor and sensory results of surgery for exotropia following botulinum toxin A injection to correct childhood esotropia. The medical records of 2445 patients treated with botulinum toxin bimedial injection were retrospectively reviewed to select patients operated on after 1 year of consecutive exotropia. We recorded age at onset of deviation, retinoscopic refractive error, visual acuity and age and dosage at the time of botulinum toxin injection. Retinoscopic refractive error, visual acuity, deviation angle, and stereoacuity before surgery for consecutive exotropia were also recorded. Families were contacted to obtain retinoscopic refraction, visual acuity, deviation angle, Bagolini test, vectography, and stereoacuity data 1 to 8 years after surgery. A total of 5 children with acquired esotropia and 2 with infantile esotropia were included. A high dose of the toxin per injection might increase the risk of consecutive esotropia. Preoperative mean exotropic deviation was 15.42 prism diopters (PD) (range, 10-25 PD), and stereoacuity was not measurable before surgery. Postoperative mean deviation was 6 PD (range, 4-8 PD), and mean stereoacuity was 447.14 arc seconds. In 2 patients, suppression of the nondominant eye was detected. Three children had poor stereoacuity. Surgery for exotropia following botulinum toxin injection in children is effective from a motor and sensory point of view.

Long-Term Results of Bilateral Medial Rectus Recession for Congenital Esotropia

This study assessed the long-term results of orthophoria obtained with bilateral medial rectus recession for congenital esotropia. The medical records of 214 patients who underwent bilateral medial rectus muscle recession between January 1995 and January 2000 were reviewed. Patients were excluded if neurological abnormalities or developmental delays were documented and if structural eye abnormalities were present. Mean follow up was 54.2 months (range, 36 to 96 months). Rates of reoperation for residual esotropia, consecutive exotropia, oblique muscle overaction, or dissociated vertical deviation were determined. Forty-five (21%) patients underwent surgery for residual esotropia, 32 (15%) underwent surgery for consecutive exotropia or dissociated horizontal deviation, and 39 (18%) underwent surgery for oblique muscle overaction and dissociated vertical deviation. To maintain long-term alignment of congenital esotropia, additional surgical procedures may be required. The success rate of bilateral medial rectus recession for ocular realignment with one operation is approximately 50%. This method is quicker, simpler, and less traumatic than three or four muscle operations. In addition, the lateral rectus and oblique muscle are left unoperated for future surgeries if necessary.

The surgical management of consecutive exotropia

Purpose To review the results and techniques of surgical treatment of consecutive exotropia. Methods We performed a retrospective chart review of all patients who underwent surgery for consecutive exotropia in a pediatric ophthalmology practice between 1992 and 2001. Patients were excluded if follow-up lasted < 6 weeks or if exotropia was caused by other ocular disorders such as previous trauma or congenital cataracts. Results Fifty-nine patients were identified. The procedure performed in the majority of cases was unilateral lateral rectus recession and medial rectus advancement to the original insertion. Seven patients underwent bilateral lateral rectus recession, and 6 underwent lateral rectus recession combined with medial rectus resection. The mean interval between original surgery and surgery for consecutive exotropia was 14.1 years (range 4 months to 47.5 years). The mean preoperative distance exodeviation was 31.7 prism diopters (PD). Satisfactory alignment (ie, within 10 PD of orthophoria) was achieved in 36 patients (61%) at week 1 and 42 patients (71%) at final follow-up. Mean follow up was 16.0 months. Thirty-nine patients (66%) demonstrated an exodrift after surgery (mean 7.6 PD). Conclusion Consecutive exotropia may occur many years, even decades, after esotropia surgery. Lateral rectus recession with advancement of the previously recessed medial rectus is an effective treatment. An exotropic drift occurs after consecutive exotropia surgery, usually within the first 6 weeks. A suitable ocular alignment immediately after surgery for consecutive exotropia is a small-angle esotropia of 5 to 10 PD.

Two-muscle surgery for congenital esotropia: Rate of reoperation in patients with small versus large angles of deviation

Introduction: Standard surgical treatment of congenital esotropia (CET) in patients with preoperative angles of deviation measuring ≤50 PD is well defined. However, there is controversy over the management of larger angles of esotropia. Some surgeons prefer to operate on 3 or 4 horizontal rectus muscles, while others prefer to perform large recessions of the medial rectus muscles alone. The purpose of this study was to compare the rate of reoperation after bilateral medial rectus muscle recession of smaller angle (≤50 PD) CET with the rate of reoperation after surgery for larger angle (>50 PD) CET. Methods: Medical records of 102 patients who underwent bilateral medial rectus muscle recessions between January 1991 and December 1997 were reviewed. Patients were excluded if neurologic abnormalities or developmental delays were documented before the operation, if major structural abnormalities of the eye were present, or if less than 1-month follow-up after surgery was documented. The remaining 56 patients were assigned to either the larger angle (>50 PD) or smaller angle (≤50 PD) group, based on the magnitude of their preoperative esotropia. Rates of reoperation for residual CET, for consecutive exotropia or dissociated horizontal deviation, or for dissociated vertical deviation with or without oblique muscle dysfunction were determined for each group. Results: Forty of 56 patients (71%) were assigned to the smaller angle group and 16 of 56 patients (29%) to the larger angle group. In the larger angle group, 4 patients (25%) underwent surgery for residual esotropia. In the smaller angle group, 8 patients (19%) underwent surgery for residual esotropia, 8 (19%) underwent surgery for consecutive exotropia or dissociated horizontal deviation, and 8 (19%) underwent surgery for dissociated vertical deviation or oblique muscle dysfunction. Conclusion: The success rate for ocular realignment in patients with CET by using bilateral medial rectus muscle recession did not appear to diminish when applied to deviations greater than 50 PD as compared with smaller angle deviations. Surgery on 3 or 4 horizontal rectus muscles may be unnecessary in the treatment of patients with very large angles of CET. (J AAPOS 2000;4:267-70)