OUTCOME OF SURGICAL MANAGEMENT OF RESIDUAL AND RECURRENT ESOTROPIA. ABDALLH M ALAMIN Department of ophthalmology faculty of medicine Al Azhar university ABSTRACT Aim This study: evaluates the outcome of reoperation for management of residual and recurrent esotropia. Patients and methods: Eighteen patients were included in this study 12 patients having residual esotropia, 6 patients were recurrent esotropes. All patients failed to achieve good ocular alighetment by non surgical method. All patients were subjected to complete ophthalmologic examination. General anesthesia was used for all patients, with use of the surgical microscope forced duction test done first then limbal conjunctival incision with two radial relaxing incisions gave a wider view and allowed accurate measurements from the limbus. Every case was managed individually according to its specific criteria. Results: Postoperatively 14 patients (77.77%) were favorable outcome (ocular alighenment within 10 prism diopter) after one month and the same after 3 and 6 months. Four patients were unfavorable outcome (ocular alighenment more than 10 prism diopter) unfavorable outcome was associated with high score of adhesion. Conclusion: Reoperation for management of residual and recurrent esotropia is effective treatment with favorable outcome. The best results were achieved in patients with smaller preoperative angles (within 50-60 ). The best prospects for favorable outcome occurred with a shorter time interval between surgical procedures. Keywords : Residual esotropia,recurrent esotropia 284
ABDALLH M ALAMIN INTRODUCTION Esodeviations are the most common forms of strabismus. 1 Types of esotropia include infantile, accommodative, partially accommodative, and acquired nonaccommodative. Sensory esotropia occurs in patients with poor vision in one or both eyes. Other types of esotropia include those related to a sixth cranial nerve palsy, and A or V pattern esotropia. 2-5 Unsatisfactory alignment is the most common complication of surgery for esotropia. In spite of the best efforts done at surgical planning and meticulous surgical technique, up to 20% of operations for strabismus fail to achieve the goal in terms of ocular alignment necessitating further surgery. 6 Alignment of the eyes should be assessed 6 weeks to 2 months after surgery. If the size of a residual deviation is unsatisfactory, additional surgery should be scheduled. Undercorrection of 10 prism diopters of more may respond to treatment of hyperopia when a refractive error of +1.50 or more is present. A trial of 6 weeks is indicated. 7-8 Residual esotropia of 15 prism diopters or more 6 weeks postoperatively without amblyopia or an accommodative component is an indication for additional surgery. This surgery should be performed as soon as reasonably possible. 9 Depending on the size of the residual or recurrent esotropia. When medial rectus restrictive factors or obvious errors in magnitude of the original surgery are noted, medial rectus rerecession or marginal myotomy combined with lateral rectus resection can be performed. If a monocular recession resection was performed because the original procedure and alignment is unsatisfactory, a similar procedure is performed on the fellow eye to correct alignment. 10 The aim of this study is to evaluate outcome of reoperation for management of residual and recurrent esotropia. 285
PATIENTS AND METHODS Eighteen patients were included in this study 12 patients having residual esotropia, 6 patients were recurrent esotropes. All patients failed to achieve good ocular alighetment by non surgical method. All patients were subjected to complete ophthalmologic examination the angle determined by using the Hirschberg test, cover test, and Krimsky prism test for near and distance vision. Visual acuity was examined using a Snellen acuity chart. Cycloplegic refraction was performed to exclude the accommodative component. Ocular motility, duction, and version movements were examined. Vertical incompliance (V or A pattern), oblique muscle overaction, and dissociated strabismus were recorded. Principal of reoperation: General anesthesia was used for all patients, with use of the surgical microscope when operating on previously operated muscles to avoid complications which are more common due to much scaring which might obscures normal anatomy. Forced duction test then subconjunctival saline injection to demonstrate the sites of conjunctival adhesion. The limbal conjunctival incision with two radial relaxing incisions gave a wider view and allowed accurate measurements from the limbus and proper dissection of adhesions. Every case was managed individually according to its specific criteria. The presence of records served as to which muscles were available to be operated on. Follow-up visits were conducted at 1 and 2 weeks; and 1, 3, and 6 months postoperatively. Krimsky prism test as well as eye movement were assessed during follow-up examinations. Deviations 10 from orthophoria were considered favorable outcomes 286
ABDALLH M ALAMIN RESULTS Eighteen patients were included in this study 12 patients having residual esotropia and 6 patients were recurrent esotropes. Ten patients were females (55%) and eight were males (45%) The refraction of the patients (spherical equivalent) was ranging from 2.0 to + 5.0 Patients age range between (4-29) years with a mean of ± S.D 3.83± 6.97years. The preoperative near angle of deviation ranged from 25-90Δ with a mean of ± S.D 57.25 ± 18.52 the distance deviation range from 30-90Δ with a mean of ± S.D 61.42 ± 19.55. Table (1) The age at onset of deviation ranged from 2 to 5 years with a mean of ± S.D 2.81 ± 1.1 The age at initial surgery ranged from 2.5 to 12 years with a mean of ± S.D 5.53 ± 2.87 The time interval between first and second procedures ranged from 4 months to 11 years with a mean of ± S.D 5.46 ± 3.16. Amblyopia was present in 11 patients (61%). Table (1) : Patients data. Residual or Angle after treatment Δ Angle before treatment Δ Age Sex Case Recurrence Distance Near Distance Near [years] No. Recurrent 5ET 5ET 80ET 80ET 5.5 1 Residual 5ET 5ET 40ET 40ET 6.5 2 Residual 10ET 5ET 30ET 40ET 7.5 3 Recurrent 5 ET 5ET 60ET 60ET 10 4 Recurrent 10ET 10ET 90ET 90ET 11.4 5 Residual 10ET 5ET 80ET 70ET 11 6 Recurrent 10 ET 10ET 50ET 60ET 5.5 7 Residual Ortho Ortho 80 ET 70 ET 4 8 Residual 5ET 5ET 60 ET 60ET 8 9 Recurrent 15ET 10ET 90 ET 80 ET 6 10 Recurrent 20 ET 15 ET 90 ET 90 ET 29 11 Residual 15ET 15ET 70ET 70ET 18.5 12 Residual Ortho Ortho 30 ET 25 ET 21 13 Residual 5ET 5ET 30ET 30ET 9.4 14 Residual Ortho Ortho 35ET 40ET 15.8 15 Residual 15ET 15ET 50ET 50 ET 5.5 16 287
Residual 5ET 5ET 30ET 30ET 6.2 17 Residual Ortho Ortho 40 ET 40 ET 5 18 Inferior oblique muscle overaction was present in 5patients ( 27.77% ). A pattern was present in 3 patients (16.66%) V pattern was present in2 patients (11.11%) Limitation of movements was present in 5 patients (21.7%). Normal movements were present in13patients (87.3%) Surgical procedures Bilateral medial rectus rerecessions were used in 4 patients (22.22%) and bilateral lateral rectus resections (new muscles) were used in 2 patients (11.11%). Recession-resection of 2 muscles (monocular surgery) was used in 3 patients (16.66%) and bilateral medial rectus rerecession with resection of lateral rectus (3 muscles surgery on both eyes) were used in 4 patients (22.22%). Bilateral medal rectus muscle recession was used in 2 patients (11.11%). Lateral rectus advancement combined with small resections were used in 3 patients (16.66% ) Inferior oblique recession combined with surgery on other rectus muscles were used in 5 patients (27.77% ). Conjunctival recession 3 mm was used for all cases of medal rectus recession. Score of forced duction test was zero in 9 patients (50%); score 1 in 3 patients (16.66%); score 2 in 2 patients (11.11%); score 3 in 2 patients (11.11%);and score 4 in 2 patients (11.11%)Table (2). Table (2) : Score of forced duction test. Table (2) Definition No. (%) Favorable score Patients outcome 0 No restriction. 9 (50%) 8(44.44%) 1 Minimal restriction terminally. 3 (16.66%) 2 (11.11%) 2 Eyeball could move past 2 (11.11%) 1 (5.55%) midline. 3 Eyeball could not be moved 2 (11.11%) 1 (5.55%) past midline. 4 Eyeball could not be moved. 2 (11.11%) 0 288
ABDALLH M ALAMIN Score of adhesion was zero in 10 patients (55%) score 1 in 5 patients (25%); score 2 in 2 patients (11.11%)(Figure 1); and score 3 in 2 patients (11.11%)(Figure 2)Table (3). Table (3): Score of adhesion. Table (3) Definition No. (%) Favorable score Patients outcome 0 No adhesion. 10 (55.55%) 10 (55.55%) 1 Filmy adhesions easily separable with blunt dissection. 2 Mild to moderate adhesions with freely dissectible plane. 3 Moderate to dense adhesions with difficult dissection 4 (22.22%) 3 (16.66%) 2 (11.11%) 1(5.5%) 2 (11.11%) 0% Figure 1: Mild to moderate adhesions with freely dissectible plane. Figure 2:Moderate to dense adhesions with difficult dissection 289
Postoperatively 14 patients (77.77%) were favorable outcome (ocular alighenment within 10 prism diopter) after one month and the same after 3 and 6 months. Four patients were unfavorable outcome (ocular alighenment more than 10 prism diopter) DISCUSSION Among the 18 patients included in the study, 12 patients with residual esotropia and 6 patients were recurrent esotropes there was a higher percentage of females (55%) than males (45%). The refraction of the patients (spherical equivalent) was ranging from 2.0 to + 5.0 The postoperative follow up period ranged from a minimum of 6 months to a maximum of 14 months. The smallest preoperative angle was 25 Δ for near and 30 Δ for distance and the largest was 90 Δ. Preoperative angle was the most important factor in determined the favorable outcome. Records of the previous operation were present in 30 %patients. The amount of recessions which was measured during reoperation found to be 2-3 mm less than recorded in 60 % of patients with records. This finding also met with study done by Fileus and colleagues 11 due to healing process and anterior creeping of fibrous tissues. Amblyopia was present in 9 patients (50%). Gomez De liano et al. 12 reported amblyopia in 53.3% of his patients and accused it as one of the most important factor in recurrent strabismus. Significant inferior oblique muscle overaction (more than +2) was present in 5 patients (27.77%). von Noorden 13 reported that about one third of patients with IOOA missed in diagnosis before the primary surgery and manifested later in recurrent cases All patients with inferior oblique muscle overaction were managed by inferior oblique recession without any complications. 290
ABDALLH M ALAMIN A pattern was present in 3 patients (16.66%) V pattern was present in2 patients (11.11%). During reoperation in cases of A and V patterns tendon transposition were used for treatment of this vertical deviation. In A pattern medial rectus was shifted up and lateral rectus was shifted down, in V pattern medial rectus was shifted down and lateral rectus was shifted up. 14 Postoperatively 14 patients (77.77%) were favorable outcome (ocular alighenment within 10 prism diopter) after one month and the same after 3 and 6 months. Four patients were unfavorable outcome(ocular alighenment more than 10 prism diopter). The best results were achieved in patients with smaller preoperative angles (within 50-60 ). The best prospects for favorable outcome occurred with a shorter time interval between surgical procedures. Records was present in 4 patients (22.22%) Records were absent in 14 patients (79.88%) There was insignificant statistical difference between patients with records and those without records after one month, 3 months and 6 months. There was insignificant statistical difference between those who had normal inferior oblique muscle and those who had inferior oblique overaction. Oblique muscle dysfunction can be an important factor in disrupting binocular vision and lead to post operative misalignment specially in esotropic cases 15. There was significant difference in percentage of outcome in different scores of forced duction test and different scores of adhision. Higher scores (2-3-4) were associated with less favorable outcome. Every case was managed individually according to its specific criteria. The presence of records served as to which muscles were available to be operated on. It helped to plan the surgery preoperatively. However, intraoperative plan was necessary. Cooper 16 who had suggested that for surgical planning, a previous operation could be ignored and the patient treated as a new case is not always the best way for surgical treatment 291
Few complications were met in this study. Persistent conjunctival injection was present in 2 patients (11.11%).Diplopia was present in 2(11.11%) patients for more than 3 months postoperatively. Mild limitation of adduction in one patient (5.5%) maybe due to excessive recession of the medial rectus. CONCLUSION Reoperation for management of residual and recurrent esotropia is effective treatment with favorable outcome. The best results were achieved in patients with smaller preoperative angles (within 50-60 ). The best prospects for favorable outcome occurred with a shorter time interval between surgical procedures. 292
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