Single-Stage Adjustable Strabismus Surgery under Topical Anesthesia and Propofol

Aim: To present our experience with single-stage adjustable strabismus surgery (SSASS) under topical anesthesia and propofol. Materials and Methods: Sixteen patients who either had diplopia before the surgery or were at risk of developing diplopia after the surgery were selected for this operation after evaluating their tolerance for an eyelid speculum. Recession of the lateral recti, recession, resection and advancement of the medial recti, anteriorization of the inferior oblique and marginal myotomy to the superior rectus were the procedures done under topical anesthesia and propofol. The operations were done in two phases; in the first phase, the patients were sedated for 10 minutes with intravenous propofol (2 mg/kg) and the operation was done under topical anesthesia with 2% lidocaine. In the second phase, the patients were conscious and the adjustments were made. Results: None of the patients complained of significant pain during the surgery. No complications occurred during and after the procedure and no patients had diplopia during the postoperative follow-up. Conclusions: Single-stage adjustable surgery is practical and avoids the risks of regional and general anesthesia. The only disadvantage is the pain that some patients experience. We found that it is feasible to use propofol for this surgery; it provides deep sedation and prevents pain from being felt during the operation, and its short elimination half-life provides rapid awakening for the adjustment phase.     

Application Value of Topical Aneasthesia in Children Strabismus Surgery

 PURPOSE: Comparison of topical vs general aneasthesia for strabismus surgery.METHODS: Preoperative patients (aged 6～12 years) were divided into two study groups: the topical aneasthesia group (n=22), and the general aneasthesia group (n=21). The study groups were compared on the following measures: analgesic effect, surgical correction effect, eye-heart reflex, preoperative preparation time and operation time, using t-tests or X2 tests where appropriate.RESULTS: Compared with the general aneasthesia group, the topical aneasthesia group gained better surgical correction results (P<0.05), had a lower rate of eye-heart reflex (P<0.05), and had a shorter preoperative preparation time (P<0.001). No significant difference was observed between the groups in terms of the analgesic effect or operation time (P>0.05).CONCLUSION: Topical aneasthesia represents a safe and effective alternative to general aneasthesia for strabismus surgery in children.      

Adjustable Strabismus Surgery under Topical Anesthesia: Alignment in Supine vs Seated Position

Purpose: To compare ocular deviation in the operating room depending on whether the patient is in supine decubitus or seated after single-stage adjustable strabismus surgery under topical anesthesia.

Material and method: We performed a prospective observational study of 30 patients with horizontal and/or vertical strabismus who underwent single stage adjustable strabismus surgery under topical anesthesia. Both distance and near deviation were evaluated before surgery, during surgery in both positions (seated and supine), and at 1 day, 1 month, and 3 months after surgery. A final horizontal deviation <10 pd and a vertical deviation <5 pd without diplopia was considered to be a good outcome (3 months after surgery).

Results: The mean age of the sample was 55 years and 76.7% were women. Most had esotropia (70%). The most frequently used surgical combination was the medial rectus and lateral rectus (36.7%). Surgical adjustment was necessary in 40% of cases. Mean preoperative deviation was 21.9 ± 12.63 pd (distance) and 20.66 ± 4.76 (near). Deviation with the patient supine was 8 ± 8.25 pd (distance) and 7.26 ± 5.81 (near). Deviation with the patient seated was 8.13 pd±8.38 (distance) and 8.5 ± 7.41 (near). There was no significant difference between the positions. Outcome was favorable in 70% of patients; this percentage increased to 83.33% at 1 day, 1 month, and 3 months after surgery.

Conclusions: No statistically significant differences were found between ocular deviations in the seated or supine position in the operating room. Outcome was favorable in most cases 3 months after surgery. Intraoperative ocular deviation was not a predictor of outcome.     

Corneal Topographical Changes Flollowing Strabismus Surgery

Purpose: To study corneal topographical changes after strabismus surgery. Methods: Computer-aided corneal topography was used in 43 strabismus patients (45 eyes) one or two days prior to and six or seven days after strabismus surgery. The spherical and cylindrical equivalents were calculated based on the simulated keratome-try.Results: After the surgery, only the changes at 3mm in the inferior quadrant were statistically significant. The changes at 3mm in the rest quadrants and the changes at 7mm were not significant. Significant changes in spherical equivalent were found post-operatively. Neither the horizontal nor the vertical meridional equivalent showed significant changes after surgery.Conclusions: The results of corneal topographical changes following strabismus surgery in our preliminary study indicated the little effect of strabismus surgery on corneal curvature and corneal astigmatism. Eye Science 1999; 15: 174 - 178.     

Delayed Conjunctival Closure in Adjustable Strabismus Surgery

Adjustable suture strabismus surgery has proved to be a significant aid in handling difficult strabismus cases, and various methods of conjunctival closure have been discussed. A new method of conjunctival closure, enabling direct visualization and manipulation of the muscle with minimal tissue drag during adjustment, is described. The conjunctiva can be fully closed over the knot after adjustment, providing increased patient comfort and a better cosmetic result.     

重视斜视术后双眼视功能的重建

双眼视是双眼输入的视觉信息进行加工整理最终形成三维立体视觉的过程，属于大脑皮层的高级认知活动。斜视因为眼位的偏斜产生复视和混淆视，进而引起视觉抑制、异常视网膜对应、注视异常、三级视功能受损等一系列双眼视异常，严重影响了双眼视觉形成和发育。手术治疗为斜视的主要的治疗方法，但斜视矫正术后大部分患者无法获得正常的双眼视功能，而斜视的治疗应以重建双眼视功能为目标。斜视治疗不仅要重视眼位的恢复，更要重视双眼视功能的重建。重建双眼视功能在减少斜视的复发率，提高斜视的治疗效果方面具有积极的作用，并大大提高斜视患者术后的生活质量。所以双眼视功能重建应在斜视治疗中占有更重要的地位。斜视的早期手术治疗是建立双眼视觉的先决条件，同时应重视术后正确的屈光矫正和弱视的治疗，正确选用训练手段，个性化制定训练方案，才能促进双眼视功能的重建。     

Diplopia after Strabismus Surgery

ABSTRACT

Diplopia is a disappointing and, at times, unanticipated consequence of what might otherwise be considered anatomically successful strabismus surgery. In this study, we review the existing literature regarding diplopia after strabismus surgery in the context of the senior author’s experience. We divide postoperative diplopia types into cases that occur in the setting of normal binocular vision (or “normal” suppression) vs. cases that are the consequence of rare or anomalous sensorial adaptations. We then discuss how to identify patients at greatest risk based on history and preoperative testing, and we offer strategies for managing these sometimes-challenging cases.     

Decreased Binocular Summation in Strabismic Amblyopes and Effect of Strabismus Surgery

Purpose: Binocular summation (BiS) occurs when binocular visual function surpasses that of the better eye alone. We sought to evaluate whether strabismic amblyopia reduces BiS more than strabismus alone, and determine whether BiS improves in strabismic amblyopes after strabismus surgery. Methods: We prospectively recruited 15 patients with strabismic amblyopia who then underwent strabismus surgery. Thirty age-matched normal subjects and 30 non-amblyopic strabismic patients served as controls. Subjects underwent binocular and monocular visual acuity testing on high-contrast Early Treatment Diabetic Retinopathy Study (ETDRS) as well as 2.5% and 1.25% Sloan low contrast acuity (LCA) charts. BiS was calculated as the difference between better eye and binocular scores. Results: Strabismic amblyopes and strabismic controls did not significantly differ in preoperative BiS, but both had subnormal BiS preoperatively on LCA charts. Among 11 strabismic amblyopes with preoperative and postoperative BiS measurements, average postoperative BiS was not significantly different from preoperative. Improved LCA BiS postoperatively occurred in some patients and was associated with measurable preoperative stereoacuity (P=0.02), older age at strabismus onset (P=0.02), and larger preoperative angle of strabismus (P=0.0043).Conclusions: In this preliminary study, strabismic amblyopes experienced subnormal BiS, but amblyopia generally did not further impair BiS beyond that due to strabismus alone. Some strabismic amblyopes experienced improved low-contrast BiS after strabismus surgery. This suggests that further investigation in larger groups of patients should be undertaken to analyze a previously unrecognized functional benefit of strabismus surgery in strabismic amblyopes.     

Oculocardiac Reflex during Strabismus Surgery: Experience from a Tertiary Hospital

Purpose: To evaluate the incidence of the oculocardiac reflex (OCR) and its associated risk factors during strabismus surgery at a tertiary referral center.

Methods: Over a 2-year period, all strabismus surgery candidates were enrolled in the study. OCR was defined as heart rate reduction ≥15% after traction on extraocular muscle(s). The rate of OCR was determined and possible associations were explored. Variables included age, gender, type of strabismus, nature of surgery (weakening versus strengthening), specified extraocular muscle, times of surgery, and the sequence of operated muscles (eg, first, second, or third operated muscle). We avoided the use of atropine pre- and postoperatively.

Results: Seventy-six patients with mean age of 15±12 years were enrolled; 51.3% of subjects were male. OCR occurred in 65 out of 76 (85.5%) patients and with 84 out of 173 (48.6%) operated muscles. OCR was more common in subjects less than 20 years of age; however, it showed a decreasing trend afterwards. OCR was more frequent during operation on cyclovertical muscles than horizontal recti (P=0.02). Moreover, during procedures on horizontal rectus muscles, OCR was more common if baseline heart rate was more than 61 (P=0.008). OCR was not correlated with gender, type of strabismus, nature of surgery, times of the surgery, or the sequence of operated extraocular muscles.

Conclusions: The great majority of patients undergoing strabismus surgery, especially younger subjects, those undergoing operation on cyclovertical muscles, and subjects with higher baseline heart rate, experience OCR during strabismus surgery. During surgery on cyclovertical muscles, the amount of pull is usually more due to more difficult exposure.     

盐酸奥布卡因表面麻醉剂在斜视矫正术中的应用

目的:探讨盐酸奥布卡因滴眼液表面麻醉下行斜视矫正术的临床麻醉效果。方法:对118例斜视患者术前滴盐酸奥布卡因滴眼液5次,常规行斜视矫正术。结果:Ⅰ级麻醉效果83例(70.3%),Ⅱ级麻醉效果34例(28.8%),因眼胃反射终止手术1例。结论:盐酸奥布卡因表面麻醉下行斜视矫正术安全、有效、并发症少,简单易行。     

Complications of Strabismus Surgery: Incidence and Risk Factors

Abstract

Purpose: To perform a systematic review of the complications of strabismus surgery, focusing on incidence and risk factors. Material and Methods: A systematic literature search was performed using the Medline and Cochrane databases. Results: Local complications, such as conjunctival injection and mild scarring, are almost universal but only rarely have long-term clinical significance. There are several important complications that are uncommon but associated with significant long-term sequelae, including slipped muscles, lost muscles, stretched scars, incarcerated muscles, pulled-in-two syndrome, periocular infections, orbital cellulitis, scleral perforations, retinal detachments, endophthalmitis, anterior segment ischemia, and surgical errors. Discussion: Strabismus surgery is associated with a number of common and serious complications, and it is important for both surgeons and patients to be aware of the risks.     

Strabismus Following Scleral Buckling Surgery

Purpose: To assess the incidence of strabismus, relationship of strabismus with type and width of scleral buckle after scleral buckling surgery for retinal detachment.

Methods: Retrospective analysis was done of 360 eyes of 344 patients treated for rhegmatogenous retinal detachment with scleral buckling surgery between January 2008 and January 2013.

Results: The mean age of patients was 38.45 ± 18.12 years (range: 7 to 89 years). Strabismus was detected in 48 out of 344 (13.95%) patients at 6 weeks after scleral buckling surgery. Horizontal deviation was the commonest type. Incidence of strabismus was higher after repeat scleral buckling surgery (4/9, 44.4%) compared to patients who had single scleral buckling surgery (44/335, 13.1%) (P=0.02). Strabismus was observed in 18.5% of patients with implants, compared to 11.3% of patients who received explants (P=0.02). Strabismus surgery was performed on 2 (4.1%) cases.

Conclusion: Horizontal strabismus is common after scleral buckling surgery for repair of retinal detachment. Repeat scleral buckling and use of implants resulted in a higher incidence of strabismus in the postoperative period. Majority of these cases resolve with conservative management.     

表麻下行斜视矫正术的临床观察

目的观察盐酸奥布卡因滴眼液联合2%利多卡因表面麻醉下行斜视矫正术的临床麻醉效果。方法对90例（175眼）斜视术前滴盐酸奥布卡因滴眼液6次,常规行斜视矫正术且术中滴2%利多卡因3次。结果麻醉效果良好,术中剪切分离时无疼痛感,仅在牵位肌肉时有酸胀不适,经解释后手术配合良好。结论斜视矫正术用盐酸奥布卡因联合2%利多卡因表面麻醉有效、并发症少。     

Multifocal Surgically Induced Necrotizing Scleritis Following Strabismus Surgery: A Case Report

Purpose: To present clinical findings of a 28-year-old woman with multifocal surgically induced necrotizing scleritis following uncomplicated strabismus surgery.

Method: A 28-year-old woman underwent uncomplicated strabismus surgery of her right eye for sensory exotropia under general anesthesia (6 mm right medial rectus muscle resection and 8 mm right lateral rectus muscle recession).

Design: Retrospective, observational case report and literature review.

Results: One month after strabismus surgery, the patient presented with surgically induced necrotizing scleritis in the nasal aspect of sclera. Bacterial culture of the bed of the scleral melt showed no growth and all laboratory evaluation was normal. The scleritis completely resolved after initiation of systemic corticosteroids and oral azathioprine. Three weeks later (after tapering dose of systemic medication), the patient returned with large area of necrotizing scleritis in the same eye, but this time in the temporal aspect of sclera.

Conclusion: To our knowledge, this is the first documented case of multifocal surgically induced necrotizing scleritis occurring after strabismus surgery. This study also highlights the fact that scleritis may recur even in an area distant from the site of surgery, despite initial control. It seems that maybe with a longer course of treatment it is less likely to recur, and tapering medications should be carefully managed.     

白内障术中局部注射麻醉导致的术后斜视及治疗

目的 在白内障手术中因球后或球周麻醉时药物可能导致眼外肌毒性而产生术后斜视及治疗.方法 对5例局部麻醉白内障术后患者,均于术后第一天去除眼罩时发现复视.于白内障术后3个月后在全麻下行受累肌肉的后徙及可调节缝线手术.结果 白内障术中局部注射布比卡因导致的眼肌麻痹于术后即发复视并持续存在.在观察病例中2例上直肌受累、3例下直肌受累.4例左眼,1例右眼.在受累肌肉行足量的肌肉后徙并可调节缝线,术后大部分注视方向复视消失,眼位调正.结论 白内障术后斜视应当注意到术中局麻药物肌肉毒性所致的斜视.早期由于肌肉麻痹产生复视,后期由于肌肉纤维化和(或)肥大产生与初始复视相反方向的复视.对受累肌肉的足量后徙和可调节缝线可以获得满意的术后效果.     

The Early vs Late Infantile Strabismus Surgery Study: do sources for bias exist in this non-randomised trial?

BACKGROUND—The Early vs Late Infantile Strabismus Surgery Study Group investigates whether early or late surgery is preferable in infantile convergent strabismus, in a non-randomised, prospective, multicentre clinical trial. The current state of the study after end of recruitment is reported here, focusing on the question of possible sources for bias in this non-randomised trial.
METHOD—The prognostic factors were analysed at baseline in order to check for imbalances between the two treatment groups. Reasons for possible differences are discussed.
RESULTS—There is no evidence for clinically relevant inhomogeneities between the two groups concerning the distribution of the three prognostic factors spherical equivalent, degree of amblyopia, and limitation of abduction. The fourth prognostic factor, horizontal angle of squint, differs significantly between the two groups.
CONCLUSION—In the analysis of the final results we may have to account for differences in angle of squint at baseline by its inclusion as a covariate or by stratification.

Keywords: convergent squint; strabismus surgery     

Ultrasound Biomicroscopy in Strabismus Surgery: Efficacy in Postoperative Assessment of Horizontal Muscle Insertions

ABSTRACT

Purpose: To study the efficacy of ultrasound biomicroscopy (UBM) in assessment of extraocular muscle insertion sites after strabismus surgery.

Methods: This double masked prospective interventional study included 16 eyes of 15 patients with deviation <60 prism diopters (PD) who underwent primary horizontal strabismus surgery. Preoperative muscle insertion was measured by UBM and compared with measurements done intraoperatively by surgical caliper. Both measurements by surgical caliper were taken intraoperatively before and after performing the planned repositioning of the muscle insertion. Postoperatively muscle insertion was remeasured by UBM and compared with the presumed muscle insertion after surgery. Clinically limits of agreement of?±?1?mm were taken as acceptable.

Results: Mean age of patients was 21?±?3 years (range 16–28 years). Preoperative average distance of the medial rectus (MR) from limbus was 5.3?±?0.3?mm (4.9–5.9?mm) by the UBM and 5.6?±?0.3 (5–6?mm) by surgical caliper (p?=?0.05). For lateral rectus (LR), UBM measurements from the limbus were 6.8?±?0.7?mm (5.9–8.3?mm) and 7.1?±?0.4?mm (6.5–8?mm) by calipers (p?=?0.067). Post–op UBM at 3 months could visualize new muscle insertion for all operated MR muscles (i.e., 100% of cases) and for LR muscles in only 50% of cases. However, accuracy could be achieved only in 78.6% of cases for MR muscle and for LR in 62.5% of cases (among LR muscles that were visible post-op). Maximum distance posterior to the limbus that the UBM was able to detect MR was 11.2?mm and for LR was 13.5?mm.

Conclusion: UBM does not detect the new position of LR with any consistency postoperatively. Even after detection of muscle, the new insertion is only within ±1?mm of the actual muscle insertion in 62.5% of the cases. Hence it is not a reliable tool for planning resurgery.     

The Application of Topical Anesthesia Combined with Subconjunctival Anesthesia for Glaucoma Surgery

Purpose: To evaluate the feasibility, reliability and analgesia effect of topical anesthesia combined with subconjunctival anesthesia in anti-glaucomatous surgery.Methods: Two hundred and four cases (357 eyes) underwent anti-glaucomatous surgeries under topical anesthesia with 0.5％ Alcaine eye drops combined with subconjunctival anesthesia with 2％ Lidocaine. The analgesic effect was analysed with visual analogue pain scale.Results: Among all of 357 eyes, 62 eyes underwent peripheral iridectomy, 67 eyes underwent simple trabeculectomy, 167 eyes underwent compound brabeculectomy and 12 eyes nonpenetrating trabecular surgery. The effects of anesthesia were as follows: 304 eyes (85.2％) were painless (Grade Ⅰ), 50 eyes (14.0％) were slight painful (Grade Ⅱ), and 3 eyes (0.8％) were more painful (Grade Ⅲ) during surgery. And no severe complications were observed in all the cases during surgery and postoperatively. Amaurosis fugax was not observed in the glaucoma patients at the late stage with narrow vi     

Botulinum Toxin Injection into Extraocular Muscles as an Alternative to Strabismus Surgery

Sixty-seven injections of botulinum A toxin were given to patients for correction of strabismus. No systemic complications of any kind have occurred. The maximum time of paralysis occurs four to five days following the injection, and then gradually diminishes, depending on the dose. The maximum correction of strabismus has been 40 prism diopters. The maximum follow-up following injection is six months. Injection of botulinum A toxin into extraocular muscle to weaken the muscle appears to be a practical adjunct or alternative to surgical correction.     

Preliminary Study: Impact of Strabismus and Surgery on Eye Movements When Children are Reading

Aim: To evaluate differences in eye movements during reading in strabismic children and in non-strabismic age-matched children, and to evaluate the potential effect of strabismus surgery on eye movement performance.

Methods: The eye movements of nine strabismic children from 11 to 15 years old were recorded with an eye tracker as they were reading a text under three visual conditions before and six months after eye surgery. The results were compared with those obtained from control groups of non-strabismic age-matched children. Eye movements were recorded during reading a text with both eyes open and under monocular vision with the dominant and non-dominant eye alternately covered.

Results: The duration of fixation was longer in strabismic children than in age-matched non-strabismic children. Children read faster under dominant eye open condition than under both eyes open condition. Surgery allowed an increase of reading speed and decrease of fixation duration. The number of backward saccades significantly decreased after surgery.

Conclusion: In strabismic children, eye movements during reading are impaired. The reduction of the squint allowed a better word comprehension.