Adjustable suture strabismus surgery

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.

Efficacy and safety of adjustable suture in horizontal strabismus: Comparative study of children versus adults

OBJECTIVE

Adjustable suture procedures allow addressing the unpredictability of some postoperative results in strabismus surgery. The purpose of the study was to compare the effectiveness of adjustable and non-adjustable suture in the treatment of horizontal strabismus in children and adults.

METHODS

Prospective study including patients undergoing strabismus surgery to correct horizontal strabismus with fixed hanging suture (non-adjustable suture group) and adjustable suture. Visual acuity, amblyopia, deviation, oblique muscle involvement, previous surgeries, nystagmus, need for adjustment, and complications were recorded. The variables were recorded in the immediate postoperative period, at one week and at 3 and 6 months.

RESULTS

186 patients were included: 157 (84.4%) with adjustable suture and 29 (15.6%) with non-adjustable suture, of which 119 were children and 67 were adults. Postoperatively, 19 children (16.0%) and 19 adults (28.4%) required adjustment (p = 0.044). Of 157 patients with adjustable suture, it was adjusted in 20% (32/157). Success after adjustment was higher for adjustable suture (91.72% vs 79.31%; p = 0.043) and remained for 6 months (p < 0.05). Previous surgery (p = 0.004) and exotropia (p = 0.018) correlated with the need for adjustment.

CONCLUSIONS

20% of patients with horizontal strabismus can benefit from a postoperative adjustment to improve the surgical result. The adjustable suture was shown to be superior to the fixed hanging suture and is an excellent surgical option, both in children and adults.

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

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.

Adjustable suture strabismus surgery in infants and children: a 19-year experience

PURPOSE

To evaluate the success rate of adjustable suture techniques in horizontal eye muscle surgery in children ≤15 years of age over a 19-year period by a single surgeon.

METHODS

The medical records of all consecutive patients in this age group who underwent horizontal eye muscle surgery from 1989 through 2012 were reviewed retrospectively. Patients were divided into two groups: those in whom a nonadjustable suture technique was used and those in whom adjustable sutures were used. The following data were collected: type of strabismus, preoperative measurements, postoperative results, and reoperation rates.

RESULTS

A total of 116 cases in the nonadjustable group and 521 cases in the adjustable group were included. In the adjustable group, adjustment was performed in 63% of the cases, because of either an under- (41%) or overcorrection (22%). The adjustment procedure was performed under topical proparacaine in 15% of cases and under intravenous propofol in 85%. For the adjustable group, 3-5 minutes more per muscle intraoperatively and 15-20 minutes for adjustment were required. No complications were encountered during the adjustment procedures. Early success rate, defined as alignment within 8^Δ of straight at 3 to 6 months' postoperative follow-up, was significantly greater in the adjustable group than in the nonadjustable group (77.7% vs 64.6% [P ≤ 0.03]). Of the adjustable patients, 15% required reoperation compared with 21% of the nonadjustable patients.

CONCLUSIONS

Use of adjustable sutures in horizontal eye muscle surgery in children ≤15 years of age provided an improved success rate and fewer reoperations compared with nonadjustable sutures.

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.

Comparison of the Effectiveness of Mitomycin-C and Viscoat on Delayed Adjustable Strabismus Surgery in Rabbits

Purpose

To determine a way to prevent the formation of adhesions and delay the time of suture adjustment in the course of adjustable strabismus surgery, an animal study was performed to assess and compare the effects of mitomycin C (Mit-C) and viscoelastic material Viscoat (sodium hyaluronate 3% and chondroitin sulphate 4%, Alcon, Fort Worth, TX).

Methods

Right eyes of 47 rabbits were divided into three groups. After recession of the superior rectus muscle (SRM), Mit-C was administered beneath and over the SRM in Group M (16 eyes), Viscoat was administered beneath and over SRM in Group V (16 eyes), and ringer lactate was administered in Group C (15 eyes). SRM then recessed 5 mm with adjustable strabismus surgery technique. Animals in each group were subdivided into 1 and 2, where 1 = adjustment 1 week postoperatively and 2 = adjustment 3 weeks postoperatively. Delayed adjustment was performed in M1 group (6 eyes), V1 group (6 eyes), and C1 group (7 eyes) after 1 week; in M2 group (6 eyes), V2 group (6 eyes), and C2 group (6 eyes) after 3 weeks. Histopathologic examinations were performed for the remaining 10 eyes without suture adjustment at the end of first and third weeks after adjustable strabismus surgery. The possible length and the necessary force to adjust and the degree of adhesions were recorded.

Results

When length and strength of the adjustment, adhesions between muscle and sclera, and adhesions between muscle and conjunctiva were taken into consideration, there was no statistically significant difference among M, V, and C groups at postoperative weeks 1 and 3. The force needed for adjustment in M1 group was statistically lower than M2 group.

Conclusions

The intraoperative use of Mit-C (0.4 mg/mL) may decrease adhesion formation in the early postoperative period, especially in the first week. The intraoperative use of Viscoat was not effective in reducing postoperative adhesions and delaying adjustment.

Clinical profiles and surgical outcomes of adult esotropia

OBJECTIVE

The aim of this study was to describe the clinical features and surgical outcomes of teenage and adult patients with esotropia undergoing strabismus surgery with adjustable sutures.

METHODS

Seventy-three patients were included in this retrospective, cohort study. Patients were stratified into group 1 (35 with childhood-onset esotropia [CET]) and group 2 (38 with adult-onset esophoria-tropia [EPT]). Preoperative immediate, 2-week, and 4-6-month postoperative measurements of ocular alignment, as well as fusional testing, were performed. Postoperative success was defined as distant (6 m) and near (33 cm) alignment within 12 prism diopters (PDs) of orthotropia in the primary position at 2 weeks and at 4-6 months with a single surgery.

RESULTS

Patients with CET more frequently had hyperopia and amblyopia and were more likely to present for surgery because of psychosocial strabismus-related problems. Patients with EPT predominantly had myopia and were more likely to experience diplopia and asthenopia. In group 1, the mean preoperative distance deviation improved from 30 PDs to 4 PDs at 2 weeks and to 4 PDs at 4-6 months (p < 0.001). In group 2, mean preoperative distance alignment improved from 22 to 3 PDs at 2 weeks and to 3 PDs at 4-6 months (p < 0.001). The mean objective, single-surgery success rate at 2 weeks was 88% and 97% in groups 1 and 2, respectively. At 4-6 months, postoperative success was 71% in group 1 and 80% in group 2. The majority of patients reported subjective improvement.

CONCLUSIONS

There are distinct preoperative differences between CET and EPT patients. Adjustable, strabismus surgery in this cohort is safe and effective in achieving subjective and objective success.

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.

Long-Term Quality of Life in Adult Patients with Strabismus after Corrective Surgery Compared to the General Population

PURPOSE

To evaluate the status of and factors associated with long-term health-related quality of life (HRQOL) in adult patients with strabismus following corrective surgery.

METHODS

Prospective cross-sectional study. A total of 122 adults who underwent corrective surgery and were followed up for at least 1 year were recruited. Pre- and post-operative HRQOL were evaluated using the Chinese version of the Adult Strabismus 20 (AS-20). Demographics and clinical characteristics were recorded. Eighty-nine age-matched, normal individuals without a history of strabismus were recruited as a control group.

RESULTS

AS-20 scores improved significantly in the psychosocial subscale and total scale after surgery for all122 patients, but not in the function subscale. HRQOL was better in the successful cases than in the non-successful cases (p<0.005). Subjects who recovered stereo function had better HRQOL than those who did not (p<0.01). Compared to the control population, the patients had poorer HRQOL post-operatively, with only approximately 30% of the subjects having scores within the normal threshold scores. The self-sense of a lack of ocular deviation and a successful surgical outcome were significant factors associated with post-operative HRQOL status.

CONCLUSIONS

HRQOL, as evaluated by AS-20 scores, improved in the patients after surgery but was worse than that in the general population. Successful surgical outcomes and a sense of good alignment were the main factors that correlated with increased post-operative HRQOL. Positive assessments of surgical results by patients may benefit post-operative HRQOL.

A comparative study of adjustable and non-adjustable sutures in primary horizontal muscle surgery in children

PurposeTo compare the results of using adjustable and non-adjustable sutures in primary horizontal strabismus surgeries in children.MethodsThis randomized control trial included 60 cases of primary horizontal deviation. The adjustable suture (AS) group included 30 patients, and the non-adjustable suture (NAS) group included 30 patients. The follow-up period was at least 6 months. A successful motor outcome was defined as orthophoria or a horizontal tropia of 8 PD or less at both near and far distances. The success rate and ocular drift were recorded and analysed.ResultsThe mean age in the AS group was 3.48±2.37 years at the time of surgery. The mean age in the NAS group was 3.55±2.64 years at the time of surgery. The success rate at the end of 6 months was 86.67% in the AS group and 73.33% in the NAS group (P=0.197). In exotropic patients, there was a mean undercorrection drift of 2.86 PD in the AS group and a mean undercorrection drift of 2.17 PD in the NAS group. In esotropic patients, there was a mean undercorrection drift of 0.26 PD in the AS group and a mean undercorrection drift of 1.83 PD in the NAS group.ConclusionThere was no significant difference between the groups. However, the success rate was clinically higher in the AS group than in the NAS group.

Selection of patients and results of 25 years of topical anesthesia and adjustable suture surgery

BACKGROUND AND PURPOSE

The author has used adjustable suture techniques either in the operating room with topical anesthesia or at a later time after retrobulbar or general anesthesia for over 25 years. Careful selection of patients is essential to the success of this technique. It is the purpose of this paper to report the selection criteria used and to compare the results of the two methods utilized.

PATIENTS AND METHODS

One hundred eighty-three patients were included in this study: 123 were operated upon with topical anesthesia. For comparison, sixty patients were included who had adjustment later in the day or the next day after having retrobulbar or general anesthesia. Both horizontal and vertical strabismus cases were included.

RESULTS

Adjustable techniques done in the operating room or at a later time have both shown significant improvement in the strabismus angle following one operation in 86% of the cases. Diplopia was eliminated in 63% of patients with this complaint. (63% and 64.5% in the two groups, respectively). Seventeen of 123 patients having topical anesthesia (13.8%) required a second operation, and 8 of 60 (13.3%) of those having a later adjustment needed further surgery.

CONCLUSION

Careful selection of patients undergoing strabismus surgery allows successful topical muscle adjustment in the operating room with results similar to adjustments done following retrobulbar or general anesthesia at a later time.

Comparing outcome criteria performance in adult strabismus surgery

PURPOSE

To evaluate the performance of motor, diplopia, and health-related quality of life (HRQOL) criteria when analyzing outcomes of adult strabismus surgery.

DESIGN

Cohort study.

PARTICIPANTS

We studied 159 adults undergoing 171 strabismus surgeries.

METHODS

All patients underwent clinical assessment preoperatively and 6 weeks postoperatively, including completion of Adult Strabismus-20 HRQOL questionnaires. Preoperatively, strabismus was classified as either diplopic (n = 117), nondiplopic (n = 38), or atypical diplopic (n = 16). To assess performance of motor, diplopia, and HRQOL criteria, success was defined a priori and applied separately and in combinations. For success: (1) motor criteria, <10 prism diopters by simultaneous prism cover test; (2) diplopia criteria, none or only rare in primary distance and for reading; (3) HRQOL criteria, exceeding previously reported 95% limits of agreement (LOA).

MAIN OUTCOME MEASURES

Surgical success rate when applying motor, diplopia, and HRQOL criteria alone and in combinations.

RESULTS

Overall, success rates were 90% for motor criteria, 74% for diplopia criteria, and 60% for HRQOL criteria. Combining criteria, the highest success rate was for motor plus diplopia criteria (67%) and the lowest success rate was when combining motor, diplopia, and HRQOL criteria (50%).

CONCLUSIONS

Applying motor criteria alone yields the highest success rates when evaluating outcomes in adult strabismus surgery, but motor criteria do not fully represent the patient's postoperative status. Combining diplopia criteria with motor criteria provides a more clinically relevant standard for judging the success of adult strabismus surgery. For HRQOL criteria, exceeding 95% LOA at 6 weeks postoperatively seems to be a difficult hurdle to clear for some individual patients, and evaluating change in HRQOL score may be more useful in cohort studies.

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.

Improved ocular alignment with adjustable sutures in adults undergoing strabismus surgery

OBJECTIVE

To assess whether outcomes of strabismus surgery are improved by using the adjustable suture technique and to determine which subgroups of strabismus patients benefit most from the adjustable suture technique.

DESIGN

A retrospective chart review.

PARTICIPANTS

A total of 535 adults who underwent strabismus surgery between 1989 and 2010.

METHODS

Success was defined as ≤10 prism diopters (PD) for horizontal deviations and ≤2 PD for vertical deviations. Differences in the proportion of successful strabismus surgery were analyzed using a chi-square test with an alpha of 0.05.

MAIN OUTCOME MEASURES

Ocular alignment in primary position at a 7-day to 12-week follow-up examination.

RESULTS

A total of 491 patients met the inclusion criteria (nonadjustable suture, n = 186; adjustable suture, n = 305). The success rates for the nonadjustable and adjustable groups were 61.3% and 74.8%, respectively (χ(2)=9.91, P=0.0016). Adjustable suture use was particularly beneficial for patients undergoing a reoperation for childhood strabismus (success rate: nonadjustable, 42.4%; adjustable, 65.7%; P=0.0268; n = 100). The differences in outcomes were not statistically significant for patients with childhood strabismus undergoing a primary surgery (nonadjustable, 65.0%; adjustable, 81.4%; P=0.1354; n = 90) or with thyroid orbitopathy (nonadjustable, 76.7%; adjustable, 74.1%; P=0.8204; n = 57).

CONCLUSIONS

Strabismus surgery using adjustable sutures was associated with improved short-term ocular alignment compared with strabismus surgery without the use of adjustable sutures. Adjustable sutures were most beneficial for patients undergoing reoperations for childhood strabismus.

Adjustable suture strabismus surgery

Surgical management of strabismus remains a challenge because surgical success rates, short-term and long-term, are not ideal. Adjustable suture strabismus surgery has been available for decades as a tool to potentially enhance the surgical outcomes. Intellectually, it seems logical that having a second chance to improve the outcome of a strabismus procedure should increase the overall success rate and reduce the reoperation rate. Yet, adjustable suture surgery has not gained universal acceptance, partly because Level 1 evidence of its advantages is lacking, and partly because the learning curve for accurate decision making during suture adjustment may span a decade or more. In this review we describe the indications, techniques, and published results of adjustable suture surgery. We will discuss the option of 'no adjustment' in cases with satisfactory alignment with emphasis on recent advances allowing for delayed adjustment. The use of adjustable sutures in special circumstances will also be reviewed. Consistently improved outcomes in the adjustable arm of nearly all retrospective studies support the advantage of the adjustable option, and strabismus surgeons are advised to become facile in the application of this approach.

The short adjustable suture

OBJECTIVE

To describe a new, adjustable suture technique for strabismus surgery that is safe and effective and allows for adjustment during the postoperative week only when required.

DESIGN

Retrospective review.

PARTICIPANTS

A total of 304 patients, of which 149 were male and 155 female, with an age range from 4 to 89 years and a median age of 42 years.

METHODS

All patients treated with the short adjustable suture technique between September 2007 and April 2009 were reviewed retrospectively. Details of cause, complexity and reoperation, operative success, requirement for adjustment, and success of adjustment were collected. Success was defined as horizontal deviation < or = 10 prism diopters (PD) and vertical deviation < or = 6 PD.

RESULTS

Overall, 84% of horizontal deviations and 74% of vertical deviations were treated successfully with 1 operation. Twenty-one adjustments were performed. Complications included 1 slipped slip knot and 6 conjunctival or Tenon cysts.

CONCLUSIONS

The short adjustable suture is a safe and effective variation of the standard slip-knot adjustable suture technique. It allows for adjustment up to 6 days postoperatively with minimal patient discomfort. When adjustment is not indicated, the suture can be left in place to absorb.

Comparison of the stability of postoperative alignment in sensory exotropia: adjustable versus non-adjustable surgery

Purpose

To compare the success rates and stabilities of postoperative alignment between adjustable and the non-adjustable surgeries in the treatment of sensory exotropia.

Methods

A retrospective analysis was performed on all patients with sensory exotropia who had undergone unilateral lateral rectus recession and medial rectus resection (R&R) between January 1998 and August 2005. Thirty-four patients underwent conventional R&R, and 20 patients underwent R&R with adjustable suture of the lateral rectus. The surgical results between the two groups were analyzed with regard to the preoperative and post-operative deviation angles and the postoperative drift. The postoperative deviation angle was measured on postoperative day 1 as well as at two weeks, three months, six months and the final visit after surgery.

Results

There were no statistically significant differences in the mean preoperative and postoperative deviation angles between the two groups. In 30 (88%) patients in the non-adjustable group and 15 (75%) patients in the adjustable group, postoperative deviation was less than 15 prism diopters (PD) at the three month follow-up. There was no significant difference in the mean postoperative drift between the two groups.

Conclusions

Strabismus surgery with adjustable sutures did not show a significantly better result than surgery without adjustable sutures in the treatment of sensory exotropia. Considering the amount of postoperative exodrift in both groups, we postulate that the immediate ocular alignment after surgery for sensory exotropia should be orthophoric or 5-6 PD of esodeviation.

One-stage vs. two-stage adjustable sutures for the correction of esotropia

BACKGROUND

The aim of this study was to evaluate the stability and the level of postoperative consciousness, nausea and vomiting, ocular pain, starting oral intake and activity, and cost-effectiveness in patients undergoing medial rectus recession surgery using an adjustable suture technique that was performed by two different methods.

METHOD

In this prospective study, we evaluated 78 patients undergoing medial rectus recession surgery. Thirty-eight patients were operated by a one-stage technique in which the whole operation was done under topical anesthesia and adjustment was done on the operating table, while 40 patients were operated by a two-stage technique in which the operation was done under general anesthesia and adjustment was done the following day at the patient's bedside. The results were recorded and compared according to the parameters given above. A scoring system was used to assess all these parameters except for stability. The stability of the procedures was evaluated according to the degrees of squint immediately after the adjustment and at least three months thereafter.

RESULTS

There was no significant difference between the procedures with regard to stability and ocular pain. During the early postoperative period, the level of consciousness was better and nausea and vomiting occurred less frequently in the patients operated by the one-stage procedure. Postoperative activity and oral intake returned to normal status more quickly in the one-stage group and the one-stage procedure was cost-effective.

CONCLUSION

We conclude that although both procedures provide satisfactory and stable results, the one-stage procedure has significant advantages over the two-stage procedure for medial rectus recession surgery in suitable cases.

Comparison of the immediate with the 24-hour postoperative prism and cover measurements in adjustable muscle surgery: is immediate postoperative adjustment reliable?

PURPOSE

Immediate postoperative adjustment after adjustable-suture strabismus surgery has been suggested as a viable alternative to the classic adjustment that is performed, usually within 6 to 24 hours after surgery. The purpose of this study was to compare the immediate postoperative eye measurements with those taken 24 hours postoperatively and to determine whether there was any significant difference between the 2 measurements.

METHODS

This was a prospective study of strabismus patients who were candidates for muscle surgery using the adjustable-suture technique. All patients received a total intravenous general anesthesia, which allowed rapid recovery of consciousness. Measurements using the simultaneous prism cover test were obtained in the recovery room immediately after the patients regained consciousness and again 24 hours after surgery. Both measurements were taken before adjustment and were compared.

RESULTS

A total of 25 patients were studied. The postoperative alignment changed significantly during the first 24 hours in 84% of our patients. The mean drift in alignment during the first 24 hours measured 7.2 +/- 4.3 prism diopters and was significantly different from 0 ( P < 0.001).

CONCLUSION

The immediate postoperative ocular alignment after adjustable strabismus surgery is significantly different from the 24 hours postoperative alignment. This difference was noticed despite using an anesthesia protocol that allowed rapid recovery and full regaining of consciousness shortly after the conclusion of surgery. This early drift should be taken into consideration if adjustment is to be made in the immediate postoperative period.

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

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

Tied and tidy: closing the conjunctiva over adjustable sutures

BACKGROUND

Adjustable sutures have revolutionized strabismus surgery. Numerous techniques have been described that aim to facilitate postoperative adjustment. Nevertheless, some sort of procedure is always necessary following adjustable suture surgery and has to be arranged within 24 hours. Where no adjustment is required, the muscle needs to be secured at the existing position and the conjunctiva, sometimes left on a loop, has to be tidied up and sutured.

METHODS

As fewer than half of the operated on eyes need a final adjustment, we describe a technique whereupon the muscle is left on a loop and the conjunctiva is closed over it with two interrupted polyglactin 910 sutures. If an adjustment is deemed necessary, one of the sutures has to be cut and replaced at the end of the procedure. When the result of squint surgery is satisfactory and no muscle movement is needed, no further manipulation of the conjunctiva is required.

CONCLUSIONS

In a series of 17 patients, we have found this technique to be excellent for patient comfort and time efficiency. We have not encountered any muscle slippage. We think that the ease of postoperative management may tend to bias the surgeon against adjustment.

Strabismus surgery: adjustable sutures-good for all?

AIMS

The role of adjustable sutures in strabismus surgery has mainly been limited to conditions like dysthyroid restrictive myopathy, blow-out fractures of orbit, aberrant regeneration of nerves, and certain other long-standing and complicated squints. In this clinical study, an attempt has been made to analyse the efficacy of adjustable sutures in squint surgery as a routine procedure. We also studied patients' acceptability and satisfaction following this procedure and analysed various factors that may influence the surgical outcome (age, sex, previous surgeries, injections of botulinum toxin, etc).

METHODS

A total number of 443 patients, aged between 13 and 78 years, who underwent strabismus surgery in our department, from January 1996 to January 2000, were included in this study. Of these patients, 141 had surgery with adjustable sutures and 302 patients without adjustable sutures. Surgical results were followed up for a period ranging from 12 to 50 months. The main outcome measure was a need for a reoperation in the two groups. In addition, we also studied patients' satisfaction with regard to final cosmetic appearance or relief of diplopia; percentage change in angle of deviation in two groups, and influence of various factors such as age, sex, previous surgeries, and injection of botulinum toxin on the final surgical outcome. The results were statistically analysed using Levene's test for equality of variances, t-test for equality of means, and statistical significance of the results was analysed by calculating P-values.

RESULTS

In total, 8.51% of the patients in the adjustable group and 27.15% in the nonadjustable group needed a reoperation. Surgical results were found to be significantly better in patients who had adjustable sutures in comparison to those who did not have adjustable sutures (P<0.005). Patients' satisfaction and percentage change in angle of deviation was also much higher in adjustable sutures group. Age, sex, number of previous surgeries, previous injections of botulinum toxin, and type and amount of deviation had no statistically significant influence on the surgical outcome.

CONCLUSIONS

Strabismus surgery with adjustable sutures has a statistically significant better, final result than surgery without adjustable sutures. Patients' satisfaction and percentage change in angle of deviation is also much higher in the adjustable sutures group. As age, sex, number of previous surgeries, previous injections of botulinum toxin, and type and amount of deviation do not influence the final outcome, this type of surgery can be performed in virtually all types of patients.

Surgical results of patients with A-pattern horizontal strabismus

PURPOSE

To investigate the surgical results of patients having horizontal strabismus with A-pattern associated with superior oblique overaction (SOOA).

METHODS

Twenty patients with horizontal strabismus (12 exotropia [XT] and 8 esotropia [ET] with no previous strabismus surgery) with SOOA-associated A-pattern were analyzed retrospectively. Motor success was defined as a horizontal deviation of 8 prism diopters (PD) or less, 6 PD or less of vertical deviation in all gazes, and no greater than 8 PD of A-pattern. Stereoacuity was measured using the Titmus test (Stereo Optical, Chicago, IL).

RESULTS

Sixty percent of patients had successful results at the final examination. No significant difference was found between the XT and ET patients in preoperative and postoperative horizontal deviations in the primary position, A-pattern collapse, or success rate (P >.05). Four patients had an induced postoperative vertical deviation. Among eight patients without stereoacuity preoperatively, four showed an average of 910 seconds of arc (40 to 3000 seconds of arc) after surgery.

CONCLUSION

Simultaneous surgery on the horizontal and SO muscles in patients with horizontal strabismus with SOOA-associated A-pattern can achieve a relatively high surgical success rate and restore binocular function.

Combined effect of polytetrafluoroethylene and 5-fluorouracil on delayed adjustable strabismus surgery

PURPOSE

To determine a more reliable method for performing delayed suture adjustment to prevent the formation of postoperative adhesions and delay the time of adjustment.

METHODS

Thirty-two rabbit eyes were divided into three groups. After recession of the superior rectus muscle, 5-fluorouracil (5-FU) was administered beneath and over the superior rectus muscle in group 5-FU (12 eyes); polytetrafluoroethylene (PTFE) and 5-FU were administered in group P-f (10 eyes); and PTFE, 5-FU, and Viscoat (chondroitin sulfate, sodium hyaluronate, Alcon Laboratories Inc, Fort Worth, Tex) were administered in group P-fv (10 eyes). Delayed adjustment was performed once on each superior rectus muscle at 1, 2, and 3 weeks postoperatively in group 5-FU and at 2 and 4 weeks postoperatively in groups P-f and P-fv. The length and force for the adjustment and the degree of adhesions were recorded.

RESULTS

The use of fluorouracil allowed adjustment to be delayed up to 1 week after surgery in three of four eyes. The combined use of PTFE and 5-FU or addition of Viscoat allowed adjustment to be delayed for up to 4 weeks after surgery in four of five eyes.

CONCLUSION

The combined use of PTFE, 5-FU and Viscoat is useful for delaying suture adjustment in rabbit eyes.

Adjustment of sutures 8 hours vs 24 hours after strabismus surgery

PURPOSE

To compare the postoperative results of adjustable-suture strabismus surgery when suture adjustment was performed 8 hours (group 1) and 24 hours (group 2) after surgery.

METHODS

A retrospective clinical study was conducted in two hospitals. Strabismus surgery and muscle adjustment were performed in 90 patients. All patients had horizontal strabismus (40 patients had esotropia and 50 patients had exotropia), and they underwent either primary surgery or reoperation. Mean age of the patients was 29.9 +/- 14.1 (range, 14 to 74) years. The angle of deviation was measured in all patients before surgery, after surgery both before and after adjustment, and at the final follow-up examination. The follow-up period was 6 to 40 months (mean, 19.6 months).

RESULTS

Preoperative data were similar in the two groups. The mean angle of deviation immediately after muscle adjustment was 0.6 +/- 6. 1 prism diopters in group 1 and 0.4 +/- 6.3 prism diopters in group 2. This similar deviation in the two groups (P =.9) changed during the follow-up period, and at the final examination the measured angles in groups 1 and 2 were -1.0 +/- 7.9 and -2.5 +/- 10.3 prism diopters, respectively (P =.48). The most considerable outcome measure was the calculated drift values. At the last follow-up these values were -1.6 +/- 5.8 for group 1 and -2.9 +/- 11 prism diopters for group 2 (P =.5). Subdividing the patients on the basis of their deviation before surgery, a postoperative drift toward exotropia was found in most patients of group 1. In group 2, however, a greater tendency toward exotropia was shown only by those patients who had displayed exotropia preoperatively, whereas patients with preoperative esotropia showed a greater tendency toward esotropia after surgery.

CONCLUSION

In patients undergoing horizontal extraocular muscle surgery with adjustable sutures, suture adjustment 8 hours or 24 hours after surgery did not produce significantly different results.

The results of adjustable suture technique in paediatric strabismus surgery

PURPOSE

Adjustable suture technique (AST) has been shown to be an effective treatment method in adult strabismus. The application of AST is not well studied in children due to potential poor cooperation during adjustment and the concern that the adjustment process can not be completed. The present series evaluates the efficacy and safety of this technique in a preselected group of children between 7 and 15 years of age.

METHODS

A retrospective review of 89 consecutive children undergoing AST was completed to assess: (1) the ability to perform and complete adjustment in children; (2) the frequency of need to perform adjustment; and (3) accuracy of surgical alignment. Only patients with horizontal rectus muscle surgery were included.

RESULTS

All children successfully completed the AST on the first post-operative day. Of the 89 patients, 24 (27%) required further adjustment by the AST. The mean follow-up period was 13.1 months. Fifty-three patients (60%) had previous strabismus surgery (range 1 to 5 operations). Sixty-six (74%) patients achieved successful alignment. Complications included slipped muscles in 1 case and difficulty in recession of the lateral rectus muscle in 1 patient.

CONCLUSIONS

Twenty-seven per cent of the patients required post-operative adjustment. The AST achieved an overall 74% successful alignment. Application of the AST should be considered in children with horizontal deviations over age 7 years, especially in the reoperations of esotropia.

Strabismus surgery using the adjustable suture technique

BACKGROUND AND OBJECTIVE

To determine the results of adjustable suture technique used in horizontal muscle surgery.

MATERIALS AND METHODS

Seventy-eight charts of patients who underwent strabismus surgery between the years 1993 and 1995 were examined retrospectively. The study included 35 cases of esotropia (ET), and 43 cases of exotropia (XT). The results of strabismus surgery were measured and compared 1 day after adjustment; the final results between 6 and 24 months after the surgical procedure.

RESULTS

Adjustment was required in 39% of all patients. The highest rate of adjustment was required in patients who underwent monocular surgery for XT (51%), and the lowest rate of adjustment was undertaken in patients who underwent monocular surgery for ET (16%). Mean changes in the angle of deviation between 1 day after surgery to the last follow up was 2.2 prism diopters (delta) (+/-11.2 delta) for cases of esotropia, and 4.6 delta (+/-8.7 delta) for exotropia. The most significant drift was found in patients with XT who underwent binocular surgery 6.8 delta (+/-0.9 delta) and the smallest drift was found in patients with ET who underwent binocular surgery 5.2 delta (+/-5.6 delta).

CONCLUSION

Esotropic and exotropic patients have a tendency to drift towards their original deviation postoperatively. It is possible, therefore, that mild overcorrection in the early postoperative period will result in better long-term results.

A comparison of sutures for adjustable strabismus surgery

BACKGROUND

The adjustable suture technique after strabismus surgery may be more easily performed if the sutures offered minimal resistance during the procedure as desired by the surgeon.

METHODS

In a rabbit model, 3 different types of 6-0 absorbable sutures-Biosorb-C (polyglycolic acid with polycaprolate coating, Alcon Surgical), coated Vicryl (polyglactin 910 coated with polyglactin 370 and calcium stearate, Ethicon), and Dexon-"S" (polyglycolic acid, Davis and Geck)-were advanced through scleral tunnels when attached and not attached to extraocular muscles. Resistance was measured with a precise strain gauge accurate to 0.1 g with an intrinsic microprocessor.

RESULTS

For unattached advancements, Biosorb-C offered significantly less resistance than Vicryl at 6 and 24 hours after operation (P < .02), whereas Dexon-"S" offered less resistance than Vicryl only at 24 hours (P = .001). At 6 hours, Biosorb-C sutures were marginally more slipperythan Dexon-"S" (P= .07). For sutures attached to extraocular muscles at 6 hours after surgery, the 3 sutures offered similar resistance. By 24 hours after the initial procedure, Vicryl presented significantly more resistance than either Biosorb-C or Dexon-"S" (P< .01 for both). For all comparisons of 6 versus 24 hours after surgery, the only significant increase in resistance were Vicryl sutures attached to muscles (P= .02).

CONCLUSIONS

These data support the use of Biosorb-C and Dexon-"S" for the adjustable suture technique whether adjusted at 6 or 24 hours after the initial procedure, although Biosorb-C may be slightly easier to adjust at 6 hours. If Vicryl is used, it would be easier to adjust the muscle 6 hours after surgery rather than after 24 hours.

Long-term results of botulinum toxin in consecutive and secondary exotropia: outcome in patients initially treated with botulinum toxin

INTRODUCTION

Long-term ocular alignment can be difficult to achieve in patients with consecutive and secondary (sensory) exotropia, and botulinum neurotoxin A (BTXA) is a recognized alternative to surgery in this group.

PATIENTS AND METHODS

We reviewed the results of 44 patients aged 15 to 77 years (mean 31 years) who underwent their first BTXA injections from 1989 to 1990. In 30% of cases the choice of toxin treatment was made by the patient. In the remainder BTXA was recommended by the clinician to assess the risk of postoperative diplopia. Thirty-three patients (75%) were consecutively exotropic and 68% of patients had had previous strabismus surgery. The mean preinjection deviation was 41 delta of exotropia (range 12 to 85 delta exotropia) and the minimum mean angle change after 1 injection was 27 delta (range 0 to 57 delta). The average number of injections was 3 (range 1 to 17).

RESULTS

Of the patient group, 59% went on to strabismus surgery, 14% continued to attend for maintenance treatment, and 9% were discharged with a small, stable deviation. The remainder were either followed up elsewhere or failed to reattend.

CONCLUSIONS

Botulinum toxin appears to be a satisfactory treatment for constant exotropia in patients at risk of postoperative diplopia who have undergone multiple operations but, because more than half the group went on to surgery, surgery as a first therapy may be preferable in uncomplicated cases.

Recovery of extraocular muscle function after adjustable suture strabismus surgery under local anesthesia

Limited data exist on the recovery of ocular motility after adjustable suture strabismus surgery performed under local anesthesia. The timing of adjustment has been chosen empirically and has varied widely. We sought to more precisely quantify the recovery of motility by measuring ductions before and after surgery with a modified arc perimeter. Twenty-one eyes of 20 patients were studied. All patients underwent adjustable suture strabismus surgery under retrobulbar or peribulbar anesthesia using 2% lidocaine with hyaluronidase. Mean ductions orthogonal to the field of action of the operated muscle(s) returned to 90% of preoperative levels between 5 and 6 hours after injection. We recommend adjustment 6 or more hours after injection, or at least 5 to 6 hours postoperatively, when 2% lidocaine with hyaluronidase is used for local anesthesia.

Stability of the postoperative alignment in adjustable-suture strabismus surgery

We reviewed the postoperative alignment drift in 201 patients between the ages of 14 and 75 years who underwent rectus muscle surgery with adjustable sutures from 1984 to 1989. We analyzed results for 42 primary esotropia (ET) surgeries and 37 reoperations (groups IA and IB, respectively), 34 exotropia (XT) primary surgeries and 66 reoperations (groups IIA and IIB, respectively), and 22 hypertropia (HT) surgeries (group III). Forty percent of patients required postoperative muscle adjustment. All patients underwent a minimum of 8-weeks follow up; 66% underwent 6-months follow up or longer. The postoperative drifts in alignment for primary surgeries versus reoperations were not significantly different for either ET or XT patients. The mean postoperative drift in prism diopters from the alignment immediately after the adjustment, or after the surgery if no adjustment was needed, for each group as measured during the most recent follow up was 1.3 eso-shift for group IA, 1.2 exo-shift for group IB, 4.8 exo-shift for group IIA, 4.1 exo-shift for group IIB, and 1.5 hyper-shift for group III. Only for groups IIA and IIB were these drifts found to differ significantly from zero. Based on these drift patterns, we align ET patients to orthotropia, XT patients to 5 to 7 delta esotropic, and HT patients to 1 to 2 delta hypotropic positions.

Adjustable suture strabismus surgery for acquired vertical deviations

Forty-seven patients undergoing 51 adjustable suture strabismus procedures for acquired vertical deviations were evaluated for preoperative and adjustment factors which might influence the postoperative alignment. The type of deviation, surgical procedure, previous surgery, immediate postadjustment alignment, and immediate postadjustment versions were assessed. Oblique muscle surgery in addition to an adjustable vertical rectus muscle significantly decreased the success rate (p = .0303). Other less important factors were a previous history of strabismus surgery and a moderate limitation of versions following the adjustment. A slight over- or undercorrection after adjustment did not affect the success.