Adjustable suture strabismus surgery

Revisiting the surgical table: An analysis of surgical dose-response in Asian exotropia

BACKGROUND

Previous research on the factors associated with surgical dose-response in strabismus surgery for exotropia has yielded inconsistent results. This study determined the factors influencing surgical dose-response in exotropia patients who underwent recession and resection (R&R).

METHODS

Exotropia patients who underwent unilateral R&R at the National Taiwan University Hospital between 2006 and 2021 were evaluated. Deviation-angle differences in prism diopters (PD) were measured preoperatively and at 1 month postoperatively. Surgical dose-response (PD/mm) was defined as the difference in deviation angle (in PD) divided by the surgical dose in millimeters. Linear and non-linear regression models were used to evaluate the influence of variables including age, sex, axial length, and preoperative deviation on surgical dose-response.

RESULTS

Overall, 295 patients (162 children; 133 adults) were included. Average surgical dose-response in the pediatric and adult groups was 2.82 ± 0.60 PD/mm and 3.02 ± 0.62 PD/mm, respectively. Male sex was negatively correlated with surgical dose-response in children. The surgical dose-response was larger in adults with longer axial length (>25.64 mm) and patients with larger preoperative deviation (>42.6 PD and >38.7 PD in pediatric and adult groups, respectively). Surgical dose-responses peaked at 35.1 years.

CONCLUSION

Age, axial length, and preoperative deviation have a nonlinear effect on surgical dose-responses in exotropia patients undergoing R&R. Surgical dose-responses were larger in patients in young adulthood, with longer axial length and larger preoperative deviation angle. A table with fitted values for surgical dose-response based on age, axial length, and preoperative deviation was established for clinical reference.

Phased strabismus surgery under topical anesthesia

PURPOSE

To evaluate the feasibility and outcomes of phased strabismus surgery under topical anesthesia, with intraoperative comparison of ocular alignment in supine and seated positions.

METHODS

This retrospective clinical investigation analyzed the data of patients who underwent phased strabismus surgery with fixed sutures under topical anesthesia. The technique consisted of 2 phases, spaced out with an intraoperative alternate prism cover test (performed in supine and seated positions): (1) surgery on one or two muscles, as defined by a preoperative surgical plan; (2) if judged necessary, a further one-muscle surgery. Surgical success was defined as a residual angle of horizontal and vertical deviation ≤±8Δ and ≤5Δ, respectively, and the presence of single binocular vision in primary position in patients with preoperative diplopia. Follow-up visits were scheduled 1 day, 1 month, and 6 months after surgery.

RESULTS

The review identified 38 patients (age range: 10-80 years). Surgery was well tolerated by all patients. Twelve (32%) required a second phase. No statistically significant differences were found for intraoperative angles of deviation in supine and seated positions. Surgical success was reached, respectively, in 88% and 87% of cases with horizontal and vertical deviation 6 months after surgery. No patients were reoperated during the follow-up period.

CONCLUSIONS

Phased strabismus surgery is a feasible technique for various types of strabismus in adults and children. Secondly, intraoperative evaluation of ocular alignment can be performed either with the patient seated or supine, with the same accuracy in terms of surgical success.

Ophthalmic surgery in New Zealand: analysis of 410,099 surgical procedures and nationwide surgical intervention rates from 2009 to 2018

BACKGROUND

Surgical intervention rates (SIR) provide a proxy measure of disease burden, surgical capacity, and the relative risk-benefit ratio of surgery. The current study assessed decade trends in ophthalmic surgery and calculated SIRs for all major classes of commonly performed ophthalmic procedures in New Zealand.

METHODS

Retrospective population-based analysis of all ophthalmic surgical procedures performed in New Zealand from 2009 to 2018. National and regional datasets from public and private health sectors and industry were analysed. SIRs were calculated for all major ophthalmic procedures, and subgrouped by patient demographics.

RESULTS

There were 410,099 ophthalmic surgical procedures completed with a 25.3% overall increase over 10 years. Procedures were mostly government-funded (51%, n = 210,830) with 71% of patients aged over 64 years. Cataract surgery (78%, n = 318,564) had the highest mean SIR (703/100,000/year) and increased by 25% during the study period, consistent with population growth in the over 64 years old age group. Vitrectomy surgery had the second highest mean SIR (67/100,000/year) and increased by 50%, well above national population growth during the study period. Other SIRs included conjunctival lesion-biopsy (38/100,000/year), glaucoma (33/100,000/year), strabismus (20/100,000/year), dacryocystorhinostomy (10/100,000/year), and keratoplasty surgery (4/100,000/year).

CONCLUSIONS

This comprehensive review of New Zealand ophthalmic surgery reports increasing SIRs that cannot be explained by population growth alone. Cataract surgery numbers increased year on year consistent with the increase in the over 64 years old population. Vitrectomy surgery growth exceeded that of the national population, including those over 64 years.

Overcorrection after vertical muscle transposition with augmentation sutures in sixth nerve palsy

PURPOSE

To report a series of cases, who developed consecutive exodeviation after vertical muscle transposition (VRT) performed for sixth nerve palsy, describe their management and analyse their outcome.

DESIGN

Retrospective case series.

METHODS

This is an institutional study on patients who developed consecutive exotropia following VRT for sixth nerve palsy in two different centres. The age, gender, cause, and time to surgery were reviewed. Ductions, versions and angles of misalignment were analysed. In those who developed an exotropia >10 PD after surgery, a second surgery was performed. The time to the second surgery, intra-operative findings, surgical procedure and outcome were studied.

RESULTS

A total of 164 cases of VRT for sixth nerve palsy were identified. Nine patients developed consecutive exotropia >10 PD (5.5%). There were no significant differences in the characteristics of those who developed overcorrection compared to those who did not. Five patients had full-tendon muscle transposition, three patients had Hummelsheim procedure and one patient had Jensen procedure. The average angle of consecutive exotropia was 26 ± 9 Δ (range 10-40 Δ). After the second surgery, angle of exotropia decreased to 21 ± 15 PD. Seven patients still had residual exotropia ≥10Δ and the exotropia was corrected in the remaining two patients. The time to second surgery in those two patients was much shorter than the other seven patients.

CONCLUSIONS

Patients who undergo VRT should be followed up in the early post-operative period and revisiting the transposition should be done immediately in case of consecutive exotropia to avoid permanent overcorrection.

Strabismus Surgery in Orthophoric Patients With Symptomatic, Asymmetric Vertical or Horizontal Incomitance

PURPOSE

To report the indications, operative strategies, and surgical outcomes of patients who undergo vertical and horizontal rectus muscle surgery for incomitant strabismus despite being orthophoric in primary gaze.

DESIGN

Retrospective, interventional case series.

METHODS

The setting for this study was an academic practice at Boston Children's Hospital. The patient population comprised 8 orthophoric patients who underwent strabismus surgery to treat vertical/horizontal incomitance. Observation procedures included review of surgical strategies, strabismus measurements in diagnostic gaze positions, and development of postoperative diplopia. The main outcome measures were preserved single vision in primary gaze, comitance, reoperation rate, and patient/surgeon satisfaction.

RESULTS

Surgical strategies included the following: (1) simultaneous recession of ipsilateral antagonist rectus muscles; (2) recession or resection of 1 rectus muscle with balancing surgery on the fellow eye; (3) restricting the range of 1 muscle (combined resection and recession or posterior fixation suture); and (4) creating an acceptable deviation in primary gaze. Mean follow-up was 5.4 months (median, 2 months; range, 2-25 months). No patient had new-onset primary gaze diplopia. The median incomitance improved by 9.5 prism diopters. No patient required additional surgery. Patient satisfaction and surgeon assessment of outcomes were high.

CONCLUSIONS

Although the risk of operating on orthophoric patients with incomitant strabismus may discourage surgeons from offering treatment, the use of specific strategies to address incomitance can preserve alignment in primary gaze while improving patient satisfaction. These strategies may also benefit patients with incomitant strabismus that is symptomatic in primary gaze.

Long-term outcomes of adjustable strabismus surgery at a Pakistani university hospital

PURPOSE

Strabismus, whether congenital or acquired, is a common visual and cosmetic problem, especially for the young. Adjustable suture strabismus surgery is not in vogue in our country. This technique gives the surgeon a second attempt to provide a better outcome for the patients. Our objective was to assess the long-term success of adjustable strabismus surgery in terms of postoperative alignment.

METHODS

We carried out a prospective study utilizing the fornix approach for adjustable strabismus surgery, in mainly horizontal, but also vertical strabismus in adults and cooperative children, to enhance the postoperative outcomes. The patient characteristics, preoperative deviation, type and pattern of strabismus, were evaluated and analyzed. The postoperative alignment was evaluated at 1 year and beyond, to assess the success of this adjustable surgery.

RESULTS

This study recruited 50 adults and children with a female predominance of 39 (78%); and with the mean age being 18.34 ± 9.88 years. Exotropia was the primary diagnosis in the majority with 21 (42%) cases; with purely horizontal strabismus in 23 (46%) cases. The mean preoperative horizontal deviation was 48.76 ± 20.35 prism diopters (PD) and the mean postoperative horizontal deviation was 2.73 ± 3.63 PD. The mean preoperative vertical deviation was 4.8 ± 8.54 PD whereas the mean postoperative vertical deviation was 0.86 ± 1.73 PD. The Wilcoxon Signed Ranks test analyzed the difference between the two which was statistically significant (p = 0.000). Surgical success, defined as postoperative horizontal alignment within ≤ 10 PD of orthotropia at the end of one year or more of follow-up after surgery, was achieved in 49 (98%) cases. The average follow-up was 21.47 ± 8.7 months.

CONCLUSION

Adjustable strabismus surgery has very good long-term outcomes in terms of postoperative alignment and patient satisfaction.

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.

Surgical outcomes of adjustment on recessed lateral rectus muscle versus resected medial rectus muscle for intermittent exotropia

BACKGROUND

To evaluate the effectiveness of resected muscle adjustment compared with the recessed muscle adjustment in patients with intermittent exotropia.

METHODS

This retrospective clinical investigation analyzed the data of patients who underwent strabismus surgery with adjustment. Patients who were followed-up for at least one and half year after adjustment were enrolled. They were divided into two groups; patients who underwent adjustment on recessed lateral rectus muscle (LR-Adj group) and adjustment on resected medial rectus muscle (MR-Adj group). Postoperative changes were compared. Surgical success was defined as horizontal deviation < 5 prism diopters (PD) esodeviation and < 10 PD exodeviation on distance measurement at 1.5 years postoperatively.

RESULTS

Forty patients were included; LR-Adj group included 21 and MR-Adj group included 19 patients. The mean esodeviation at distance fixation immediately after adjustment was 8.1 ± 5.4 PD in the LR-Adj group and 8.4 ± 4.7 PD in the MR-Adj group (P = 0.843). Postoperative exodrift occurred in both groups, and amount of exodeviation after 1.5 year were not significantly different. For the comparison of the amount of exodrift at near measurement, the amount of exodrift within 1 month after surgery was smaller in the MR-Adj group than that in the LR-Adj group (P = 0.01). Surgical success rates were 81.0% in the LR-Adj group and 84.2% in the MR-Adj group (P = 0.559).

CONCLUSIONS

The smaller amount of exodrift in the MR-Adj group may mean that the positional stability of the resected muscle is favorable in the early post-adjustment period. However, there was no significant difference groups in the final exodeviation and surgical success rate between the groups. Resected muscle adjustment was as effective as the conventional recessed muscle adjustment.

Impact of Adding Augmented Superior Rectus Transpositions to Medial Rectus Muscle Recessions When Treating Esotropic Moebius Syndrome

PURPOSE

To describe outcomes after treatment of Moebius syndrome (MBS) esotropia by adjustable bilateral medial rectus recession (BMR) with and without augmented superior rectus transposition (SRT).

DESIGN

Retrospective case series.

METHODS

Patients meeting 2014 diagnostic criteria for MBS and treated at Boston Children's Hospital between 2003 and 2019 were identified via billing records and chart review. Visual acuity, sensorimotor evaluations, strabismus procedures, and other clinical features were recorded. Surgical outcomes for patients treated with strabismus surgery (excluding those with prior surgery elsewhere) were evaluated. The primary outcome measure was postoperative alignment comparing treatment by adjustable BMR vs adjustable BMR+SRT.

RESULTS

A total of 20 patients had MBS, and 12 of these (60%) were male. Fifteen patients (75%) had primary position esotropia, and all had bilateral abduction deficit. Eight of 20 patients met inclusion criteria for primary strabismus surgery outcome. Five had undergone adjustable BMR ranging from 4.5 to 6.5 mm. Three had undergone adjustable BMR+SRT, all with 4-mm medial rectus muscle recessions. Mean preoperative esotropia before treatment by BMR was 39.5 PD (± 15 PD) with mean postoperative esotropia 9 PD (± 7.9 PD) at 6 months. Mean preoperative esotropia before treatment by BMR+SRT was 70.8 PD (± 5.9 PD) with mean postoperative esotropia 2.5 PD (± 3.5 PD) at 6 months. Significantly greater reduction in esotropia resulted from BMR+SRT than from BMR (P = .036).

CONCLUSIONS

BMR proved sufficient to treat esotropia <50 PD and BMR+SRT for greater esotropia in patients with MBS-associated abduction limitation.

Early and delayed suture adjustments after adjustable suture strabismus surgery: a randomized controlled trial

Background

Adjustable sutures increase the success rate of strabismus surgery. However, the optimal timing of postoperative suture adjustment remains controversial. This trial was aimed at comparing the surgical outcomes and pain scores of early or 2 - 4 h and delayed or 24 h postoperative suture adjustment in adult patients undergoing strabismus surgery.

Methods

An open-label, prospective, randomized, comparative interventional study was performed in consecutive adult patients scheduled for eye muscle surgery. Patients were randomized into two groups: the early group, with suture adjustment 2 - 4 h postoperatively, and the delayed group, with suture adjustment 24 h postoperatively. Subjective pain scores during the adjustment were also analyzed. The angles of misalignment at 1 and 3 months and the success rate at 3 months postoperatively were compared.

Results

Forty-five (90%) patients completed the follow-up, including 23 (92%) in the early adjustment group and 22 (88%) in the delayed adjustment group, with a mean (standard deviation) age of 25.6 (9.5) years and a male-to-female ratio of 46.7:53.3. Thirty patients (66.7%) had exotropia, and 15 (33.3%) patients had esotropia. Both groups had comparable baseline characteristics (all P > 0.05). The mean pain scores during adjustment did not differ significantly between groups (P > 0.05). The postoperative angles of alignment were comparable between the groups before suture adjustment and at the 1- and 3-month follow-ups (all P > 0.05). The success rate in the early adjustment group was slightly higher (87.0% versus 63.6%), but the difference was not statistically significant (P > 0.05). The success rate was comparable between the groups in patients with esotropia or exotropia (both P > 0.05).

Conclusions

Although the early adjustment group had a slightly higher success rate, the difference was not significant. Both groups had comparable subjective pain scores during adjustment, final motor alignment, or success rate. Future clinical trials should be performed different time intervals for postoperative suture adjustment, and subjective and objective outcomes, such as diplopia and stereopsis, should be compared between patients with a first strabismus surgery and those who underwent reoperation. This could better resolve the persistent controversy related to the optimal time for suture adjustment.

Limbal Versus Fornix Incision for Strabismus Surgery: Preferences from a Consultant to a Trainee Level in Saudi Arabia

PURPOSE:

This study aims to identify the use of limbal versus fornix incisions among strabismus surgeons in Saudi Arabia and the preferred approach to teaching trainees with the shortest learning curve.

METHODS:

Two designed questionnaires were sent to local strabismus surgeons and ophthalmology trainees.

RESULTS:

A total of 127 participants responded to our survey: fifty-nine consultants (53% Saudi nationals and 43% expat ophthalmologists) and 68 trainees. The limbal approach was the preferred approach for all settings, including the primary pediatric procedure (30, 55.9%), pediatric reoperation (40, 64.7%), adult primary procedure (32, 55.9%), and reoperation (40, 70%). The reason was attributed to better exposure. As for fornix incision, the most commonly cited reason was less pain and discomfort. For the adjustable suture technique, 29 (49.2%) did not use adjustable sutures, and 22 (37.3%) prefer the limbal approach. When we compared Saudi versus non-Saudi surgeons, 26 (83.87%) Saudi surgeons were trained to perform the limbal method, whereas 16 (57.14%) non-Saudi surgeons were trained to perform the fornix approach. Of the trainees, 35 (51%) were trained on the limbal approach. When asked about the learning curve for different methods, 41 (60.3%) noted a faster learning curve with the limbal approach.

CONCLUSION:

Despite the many advantages of the fornix incision, it remains uncommon in our region. Each technique of strabismus surgery has its advantages and disadvantages. Programs should teach all methods to trainees. One should add all styles to his armamentarium and choose the appropriate one for each patient.

Surgical Outcomes of Nonadjustable Modified Harada-Ito Surgery

Purpose

This study aimed to investigate the surgical outcomes of nonadjustable Harada-Ito surgery under general anesthesia.

Methods

Twenty-two patients who underwent nonadjustable modified Harada-Ito surgery under general anesthesia were reviewed retrospectively. Among them, 21 out of the 22 patients who were followed up for 6 months after surgery were included in this study. Subjective cyclotorsion (double Maddox rod test) and objective cyclotorsions (fundus photography) were measured. Success of the surgery was defined as follows: success (the patients do not acknowledge diplopia at any direction), partial (the patients feel diplopia at a specific direction, but they do not feel discomfort in routine life), and fail (the patients feel diplopia in primary gaze, hence requiring a thorough investigation).

Results

The mean age of the patients (18 male and 3 female) was 56.5 years (range, 40–77 years). Based on the alternate prism cover test, the patients had 4.2 ± 3.0 prism diopters of vertical deviation. The corrected amounts of cyclotorsion based on the double Maddox rod test and fundus photography were 14.8° ± 7.5° and 9.8° ± 7.9°, respectively, and were significantly different between the two methods (p = 0.006). After the surgery, 20 out of the 21 patients (95.2%) completely recovered from diplopia in the primary gaze. However, among the 20 patients, seven complained of diplopia in the secondary gaze (down gaze, four patients; head tilt gaze, three patients). The success group had a smaller preoperative subjective excyclotorsion than the partial and fail groups (12.6° ± 2.5° and 21.0° ± 8.9°, respectively; p = 0.046).

Conclusions

Nonadjustable modified Harada-Ito surgery under general anesthesia has favorable success rate, and preoperative subjective excyclotorsion can be a prognostic factor in patients with bilateral superior oblique palsy.

Surgical planning of horizontal strabismus using multiple output regression tree

Strabismus is an eye disease that affects about 0.12%-9.86% of the population, which can cause irreversible sensory damage to vision and psychological problems. The most severe cases require surgical intervention, despite other less invasive techniques being available for a more conservative approach. As for surgeries, the treatment goal is to align the eyes to recover binocular vision, which demands knowledge, training, and experience. One of the leading causes of failure is human error during the measurement of deviation. Thus, this work proposes a new method based on the Decision Tree Regressor algorithms to assist in the surgical planning for horizontal strabismus to predict recoil and resection measures in the lateral and medial rectus muscles. In the presented method, two application approaches were taken, being in the form of multiple single target models, one procedure at a time, and the form of one multiple target model or all surgical procedures together. The method's efficiency is indicated by the average difference between the value indicated by the method and the physician's value. In our most accurate model, an average error of 0.66 mm was obtained for all surgical procedures, both for resection and recoil in the indication of the horizontal strabismus surgical planning. The results present the feasibility of using Decision Tree Regressor algorithms to perform the planning of strabismus surgeries, making it possible to predict correction values for surgical procedures based on medical data analysis and exceeding state-of-art.

Anaesthesia for ophthalmic procedures in patients with thyroid eye disease

Thyroid eye disease is an autoimmune inflammatory disorder of the orbit in adults. It causes inflammation, expansion and fibrosis of orbital fat, muscles and the lacrimal gland, leading to facial disfigurement, functional disability and, in severe cases, blindness. Overall, approximately 20% of affected patients need some form of surgical intervention requiring anaesthesia. This narrative review explores the background of thyroid eye disease, surgical procedures performed and their implications for anaesthesia. General anaesthesia is used for orbital decompression procedures, strabismus correction surgery and complex oculoplastic procedures. Local anaesthetic infiltration or regional anaesthesia under monitored anaesthesia care are the techniques most commonly employed for eyelid retraction surgery. It is important to limit the volume of local anaesthetic agent used during infiltration and continuously monitor the orbital volume and ocular pressure with a ballottement technique. In addition, the contralateral eye should be checked and, if necessary, protected against corneal exposure. Retrobulbar, peribulbar and sub-Tenon's blocks are best avoided. Topical anaesthesia has been used for some strabismus correction surgery but its use is limited to motivated and cooperative patients only.

Incidence of symptomatic vertical and torsional diplopia after superior rectus transposition for esotropic Duane syndrome and abducens nerve palsy

PURPOSE

To report the incidence of symptomatic vertical and torsional diplopia after superior rectus transposition (SRT) for esotropic Duane syndrome and abducens nerve palsy.

METHODS

The medical records of patients with esotropic Duane syndrome or abducens nerve palsy seen at Boston Children's Hospital (2006-2018) and treated with unilateral SRT with or without augmentation was performed. The primary outcome was incidence of postoperative vertical or torsional diplopia in primary position. The secondary outcome was induced vertical deviation in affected side gaze.

RESULTS

A total of 69 patients met inclusion criteria: 32 with abducens nerve palsy and 37 with esotropic Duane syndrome. Vertical alignment changed in both hyper- and hypotropic directions. Median pre- and postoperative vertical deviation in primary gaze was 1.1^Δ (10th-90th percentile, 0^Δ-6^Δ hypertropia) and 0.4^Δ (10th-90th percentile, 6^Δ hypotropia to 8 ^Δ hypertropia), respectively. Postoperative vertical diplopia occurred in 7%, including 4 of 49 treated with loop myopexy (8%), 1 of 13 without augmentation (8%), and 0 of 7 treated with sclera-fixated augmentation. All but one was successfully treated with prism or secondary surgery. Intorsional change predominated, but no patient had torsional diplopia post adjustment. Vertical misalignment in affected side gaze increased from 19% to 45% after SRT (P = 0.01).

CONCLUSIONS

In this largest-to-date review of patients treated with SRT, with or without MR recession, no patient developed persistent torsional diplopia, while 7% developed symptomatic vertical diplopia in primary position, similar to the reported incidence after balanced vertical rectus transposition. Vertical misalignment in affected side gaze increased, however fusion is already limited by unresolved esotropia in this field.

Anaesthetic considerations for strabismus surgery in children and adults

Strabismus correction surgery is the most common eye operation in children. Adults have approximately a 4% lifetime risk of developing strabismus. Current treatment options include pharmacological injection of botulinum toxin or bupivacaine, conventional corrective surgery, adjustable suture surgery and minimally invasive surgery. Repeated surgery is common as each operation has a 60%-80% chance of successful correction. The benefits of early surgical correction in large-angle strabismus in children outweigh the risks of anaesthesia. General anaesthesia is suitable for patients of all age groups, for complicated or repeated surgery, and bilateral eye procedures. Regional ophthalmic block reduces the incidence of oculocardiac reflex and emergence agitation, and provides postoperative analgesia, but requires a cooperative patient as many experience discomfort. Topical anaesthesia has been used in pharmacological injection, minimally invasive surgery, uncomplicated conventional strabismus surgery and some adjustable suture strabismus surgery. Its use, however, is only limited to cooperative adult patients. Prophylactic antiemesis with both ondansetron and dexamethasone is recommended, especially for children. A multimodal analgesia approach, including paracetamol, intravenous non-steroidal anti-inflammatory drugs, topical local anaesthetic and minimal opioid usage, is recommended for postoperative analgesia, while a supplementary regional ophthalmic block is at the discretion of the team.

One-Month Postoperative Horizontal Strabismus Surgery Outcomes Using Adjustable and Nonadjustable Sutures

INTRODUCTION

Previous series suggest adjustable sutures (AS) in adult strabismus surgery yield improved ocular alignment and better success rates compared to nonadjustable sutures (NAS). We questioned whether these differences are clinically significant and whether they justify the added time and discomfort required for AS.

METHODS

We reviewed all available records of adults undergoing horizontal strabismus surgery by the last two authors between 2000 and 2014. Independently, the two surgeons developed a preference for NAS midway through the study period, permitting comparisons between two treatment groups. Results were assessed at one to two months postoperatively. The primary outcome was alignment in primary position at one to two months postoperatively. The secondary outcome was success rate, defined as <10PD residual or consecutive deviation.

RESULTS

We included 184 patients, 68 with AS and 116 with NAS. No significant difference in primary position alignment at 1-2 months was noted between AS and NAS for esotropia (P = .26) or for exotropia (P = .10). Success rates were similar (P = .58 for esotropia and P = .34 for exotropia).

DISCUSSION

Although we acknowledge limitations in this retrospective study, our results suggest that AS overall was not associated with improved alignment or success rates, compared to NAS, at 1- to 2- months postoperatively.

CONCLUSIONS

Although adjustable sutures represent a valuable surgical option at the discretion of individual surgeons and their patients, we no longer routinely use AS in all adult cases. A prospective study to evaluate long-term outcomes would be helpful.

Topical Anesthesia in Children With Intraoperative Adjustable Strabismus Surgery

PURPOSE

To evaluate strabismus surgery with intraoperative adjustment of sutures under topical anesthesia in children.

METHODS

Nineteen children with horizontal deviation underwent a one-stage surgical technique performed under topical anesthesia. Surgery consisted of unilateral or bilateral recession and/or resection of horizontal muscles or the medial or lateral rectus muscles, with intraoperative adjustment of sutures based on alternate prism cover test. Follow-up was done at 1 day and 1, 3, and 6 months postoperatively.

RESULTS

Mean age at surgery was 12.68 ± 2.50 years (range: 8 to 16 years). Mean preoperative angle of deviation was 24.21 ± 11.20 prism diopters (PD) (range: -50 to +30 PD) at distance. Mean postoperative angle of deviation at 6 months was 4.11 ± 2.87 PD (range: -10 to +10 PD) at distance. In esotropic patients, the average angle of deviation decreased from +23.80 ± 5.89 PD preoperatively to +4.80 ± 3.35 PD at 6 months, whereas in exotropic patients it decreased from -24.36 ± 12.76 to -3.86 ± 2.77 PD. Seventeen of 19 patients (89%) remained comfortable during surgery, whereas 2 needed an intravenous injection of propofol. The success rate, defined by a postoperative residual angle of deviation of ±8 PD or less, was 89% at 6 months.

CONCLUSIONS

Strabismus surgery with intraoperative suture adjustment under topical anesthesia in children is a tolerable procedure with encouraging outcomes, representing an alternative to general anesthesia in well-selected children. Clinical evaluation of children and parents is fundamental to predict a likely poor collaboration of the child during surgery, which, if present, would require surgery under general anesthesia. [J Pediatr Ophthalmol Strabismus. 2019;56(3):173-177.].

Transposition procedures in Duane retraction syndrome

Duane retraction syndrome, or Duane syndrome (DS), is one of several congenital cranial dysinnervation disorders. Patients present with limited horizontal eye movement(s) and globe retraction with eyelid fissure narrowing on attempted adduction due to co-contraction of the lateral and medial rectus muscles in one or both eyes. Various surgical approaches have been proposed to improve binocular alignment, reduce head turn, and minimize undesirable up- or downshoots in DS. Transposition procedures are one such approach, and a number of techniques have been described. These may involve one or both vertical rectus muscles and may or may not include full or partial disinsertion of the rectus muscle(s) from the insertion. Options involving both vertical rectus muscles include full vertical rectus transposition (VRT), partial VRT, rectus muscle union, and other modifications to be discussed. Options involving one vertical rectus muscle include superior rectus transposition (SRT) and inferior rectus transposition (IRT). The effectiveness of any transposition procedure may be enhanced with augmentation (posterior fixation) sutures, resection of the transposed muscle(s), and/or simultaneous weakening of the ipsilateral medial rectus muscle. This review discusses the indications, strengths, weaknesses, and other considerations of these approaches within the context of DS. Since the majority of DS cases are unilateral and most have the esotropic form, this will be the main focus of the review, although other forms will also be discussed.

Retrobulbar anaesthesia for adjustable strabismus surgery in adults: a prospective observational study

OBJECTIVE

To characterize the ocular response to retrobulbar anaesthesia and to evaluate the efficacy of retrobulbar anaesthesia for adjustable strabismus surgery in adults.

DESIGN

Prospective observational study.

PARTICIPANTS

Adult patients undergoing adjustable strabismus surgery under retrobulbar anaesthesia.

METHODS

Surgical success was defined by ocular alignment within 10 prism diopters (PD) of orthotropia for horizontal rectus surgery and within 5 PD for vertical rectus surgery. After retrobulbar injection of Xylocaine with epinephrine, the onset time and the degree of visual impairment, ocular akinesia, and analgesia were evaluated. Postoperative parameters included the restoration of vision, onset of pain, resolution of ptosis, normalization of pupil, resolution of extraocular motility deficits, and the timing of postoperative adjustment. Perioperative complications were also documented.

RESULTS

A total of 33 patients were initially included in this study. Two patients experienced complications (perioperative retrobulbar hemorrhage, postoperative suprachoroidal hemorrhage) and were excluded from data analysis. Of the remaining 31 patients (mean age, 50.2 ± 14.8 years), surgical outcome was satisfactory in 30/31 (96.8%) patients at the first postoperative visit and in 15/19 (78.9%) cases at last follow-up (mean, 6.1 ± 1.6 months). Excellent intraoperative ocular akinesia and analgesia was achieved with retrobulbar anaesthesia. After retrobulbar injection, visual impairment was the first to resolve to preoperative levels within (mean ± SD) 3.7 ± 1.9 hours postinjection, followed by onset of pain at 4.1 ± 1.0 hours, resolution of ptosis at 4.3 ± 1.9 hours, and normalization of pupil reactivity at 6.1 ± 1.0 hours. The resolution of anaesthesia upon extraocular motility occurred within 5.7 ± 1.0 hours postinjection (range, 4.5-8.0 hours), allowing for subsequent same-day postoperative adjustment.

CONCLUSIONS

Retrobulbar anaesthesia in the context of adult, adjustable strabismus surgery is a relatively safe and effective technique. It provides excellent intraoperative analgesia and akinesia. Retrobulbar anaesthesia enables for same-day suture adjustments to be reliably performed.

Reoperation following strabismus surgery among Medicare beneficiaries: Associations with geographic region, academic affiliation, surgeon volume, and adjustable suture technique

Purpose:

The objective of this study was to determine the associations of strabismus surgery reoperation rates in a large national database of provider payments with geographic region, practice type and volume, and the availability of adjustable suture technique.

Methods:

Fee-for-service payments to providers for medicare beneficiaries having strabismus surgery between 2012 and 2015 were retrospectively analyzed to identify reoperations in the same calendar year. The adjustable-suture technique was considered to be available to the patient if the patient's surgeon billed for adjustable sutures. Predictors of reoperation in the same calendar year were determined by multivariable logistic regression.

Results:

Availability of the adjustable suture technique was not associated with reoperation rate in multivariable analysis among 5971 patients having horizontal muscle surgery (odds ratio, [OR] 0.86, P = 0.29), 2840 patients having vertical muscle surgery (OR 0.98, P = 0.93), or 1199 patients having surgery with scarring or restriction (OR 0.86, P = 0.61). For horizontal surgery, the reoperation rate was higher in academic practices (OR 1.67), as compared with community practices, and in the South (OR 2.85) and West (OR 1.92, all P < 0.001). The reoperation rate was unchanged with surgeons in the lowest-quartile of surgical volume. Among surgeons paid for horizontal surgery, 45% of surgeons in the Northeast, the West, or Florida coded for adjustable sutures, compared with 8% of surgeons elsewhere (P < 0.001).

Conclusion:

The availability of the adjustable-suture technique was not associated with reoperation rate after strabismus surgery in this large national database. Having surgery by a lower-volume surgeon was not associated with a higher reoperation rate. The reoperation rate was higher when surgery was conducted in an academic practice, or in certain regions of the country. Adjustable sutures are largely a bicoastal practice.

Immediate Postoperative Alignment Measurements as a Predictor of Alignment Stability in Fixed Suture Strabismus Surgery

PURPOSE

To evaluate the use of immediate postoperative alignment measurements as a predictor of future alignment stability in fixed suture strabismus surgery.

METHODS

Forty-seven patients were prospectively evaluated after undergoing horizontal or vertical rectus muscle surgery using a fixed suture technique. Alignment measurements were taken approximately 1 hour, 1 to 3 weeks, and 2 to 3 months postoperatively. A Spearman correlation coefficient was used to compare measurements from the immediate postoperative period to the 2- to 3-month postoperative period. Patients with dissociated strabismus, only oblique muscle surgery, or poor vision in one or both eyes precluding precise alternate cover test were excluded.

RESULTS

Mean age of all patients was 46.7 years (range: 12 to 86 years). Twenty-two patients underwent surgery for exotropia: 19 for esotropia and 6 for hypertropia. Mean alignment for all surgeries was 2 prism diopters (PD) undercorrection in the immediate postoperative period, which was similar to the mean of 4.6 PD undercorrection at 2 to 3 months postoperatively. However, the Spearman correlation between the immediate postoperative and 2- to 3-month postoperative measurements was 0.18 for all surgeries, 0.03 for exotropia, 0.56 for esotropia, and 0.40 for hypertropia. The overall success rate, defined as 8 PD or less of horizontal deviation and 4 PD or less of vertical deviation, was 77% at 2 to 3 months postoperatively.

CONCLUSIONS

The relationship between immediate postoperative alignment and future alignment stability in fixed suture strabismus surgery has not been previously defined. The current study demonstrated that although the surgical success rate was reasonably good, poor correlation occurred between the alignment immediately postoperatively and 2 to 3 months postoperatively. [J Pediatr Ophthalmol Strabismus. 2018;55(4):240-244.].

Early postoperative changes of motor alignment after surgery for intermittent exotropia

PURPOSE

To evaluate the early postoperative changes of the angle of deviation after surgery for intermittent exotropia.

METHODS

We retrospectively reviewed the medical records of 114 patients who had been surgically treated for intermittent exotropia and followed-up on postoperatively for 1 month or more. Patients were observed at postoperative 6 h, 1 day, 1 week, and 1 month. The main outcome measure was the change of the angle of deviation during the early postoperative period (from 6 h to 1 day postoperatively).

RESULTS

The mean preoperative angle of exodeviation was 26.3 ± 7.6 PD at distance and 25.4 ± 10.3 PD at near. The angle of deviation was -3.3 (esodeviation) ± 7.0 PD at distance and -0.7 ± 7.1 PD at near at postoperative 6 h, and -3.7 ± 6.9 PD and -0.8 ± 6.8 PD at postoperative 1 day. Neither of these sets represented a significant change from 6 h to 1 day postoperatively (p = 0.300 at distance, p = 0.945 at near). However, in 25 patients (21.9%) the angle of deviation changed 5 PD or more from 6 h to 1 day. Among them, ten showed exodrift and 15 esodrift. At postoperative 1 month, the deviations became significantly more exotropic compared with postoperative 1 day (p < 0.001).

CONCLUSIONS

The mean angle of deviation showed no significant change from 6 h to 1 day postoperatively, but 21.9% of patients showed a change of 5 PD or more in this period. These results should be considered in determining the time and the target angle of adjustment in adjustable strabismus surgery for exotropia.

Plication as an alternative to resection in horizontal strabismus: A randomized clinical trial

Purpose:

Resections and plications tighten recti although the latter are less traumatic, potentially reversible, quicker, and vascularity preserving. To compare inflammation, scarring, and alignment in horizontal strabismus, operated uniocularly by either resections or plications (with recessions): recession and resection (R&R) or recession and plication (R&P) groups. This was a prospective, patient and assessor blind, randomized trial.

Methods:

All consenting strabismus patients qualifying for the first-time uniocular horizontal rectus surgeries underwent detailed ocular examination and were randomized into standard R&R or R&P groups. For the latter, we folded the tendon-muscle strap the desired amount using 6-0 polyglactin, suturing it to its insertion, entailing no disinsertion. We compared the groups for inflammatory grades (individually for congestion, chemosis, discharge, foreign-body sensation, and drop intolerance and aggregated to a total inflammatory score (TIS), scar visibility (SV) at 1 m, and successful alignment (≤10 prism diopter of orthotropia). We used Mann–Whitney and Fisher's exact tests, with significance at P ≤ 0.05.

Results:

We randomized 40 patients: 22 to R&R and 18 to R&P. The groups were comparable in age, strabismus onset and duration, and strabismus amount. The inflammatory scores, both individual and TIS, were comparable at all time-points: all P > 0.05. SV proportions were not significantly different: 16/22 in R&R versus 9/18 in R&P; P = 0.19. There were no significant differences in success rates: 14/22 versus 10/18, P = 0.74.

Conclusion:

Our study shows that plication is similarly effective as resection, when combined with recession in horizontal strabismus, and should be resorted to more frequently.

Modified adjustable suture hang-back recession: Description of technique and comparison with conventional adjustable hang-back recession

PURPOSE

This study aims to describe and compare modified hang-back recession with the conventional hang-back recession in large angle comitant exotropia (XT).

METHODS

A prospective, interventional, double-blinded, randomized study on adult patients (>18 years) undergoing single eye recession-resection for large angle (>30 prism diopters) constant comitant XT was conducted between January 2011 and December 2015. Patients in Group A underwent modified hang-back lateral rectus recession with adjustable knot while in Group B underwent conventional hang-back recession with an adjustable knot. Outcome parameters studied were readjustment rate, change in deviation at 6 weeks, complications and need for resurgery at 6 months.

RESULTS

The groups were comparable in terms of age and preoperative deviation. The patients with the modified hang back (Group A) fared significantly better (P < 0.05) than those with conventional hang back (Group B) in terms of lesser need for adjustment, greater correction in deviation at 6 weeks and lesser need for resurgery at 6 months.

CONCLUSION

This modification offers several advantages, significantly reduces resurgery requirement and has no added complications.

Anterior segment ischemia: etiology, assessment, and management

Anterior segment ischemia (ASI) is a potentially serious but rare complication of strabismus surgery. Among several risk factors, ASI occurs after strabismus surgery because of the nature of the anterior segment circulation. Disinsertion of rectus muscles leads to a decrease in the blood supply to the various anterior segment structures. We report a series of retrospective and prospective studies performed by our group focused on determining the risk of anterior segment ischemia following strabismus surgery, diagnosis, and modifications to surgical techniques to minimize the impact on anterior segment circulation. We found a significant decrease in postoperative anterior segment blood flow when operating vertical rectus muscles. Plication procedures preserve anterior segment circulation, and modifications to the technique allow the performance of adjustable sutures. Small adjustable selective procedures that spare the ciliary vessels have been demonstrated to be effective in patients with vertical and torsional diplopia. Ciliary sparing augmented adjustable transposition surgery decreases the risk of anterior segment ischemia while allowing management of potential post-operative alignment complications. Finally, ocular coherence tomography angiography is a valuable quantitative and qualitative technique to evaluate anterior segment ischemia. Strabismus surgeons should be aware of the risks of anterior segment ischemia when operating vertical rectus muscles. Modifications to standard surgical techniques allow surgeons to perform complex strabismus surgery in patients at risk for anterior segment ischemia.

Adjustable suture strabismus surgery in pediatric patients using pull-string technique

BACKGROUND/PURPOSE:

The concept of adjustable suture has been developed in strabismus surgeries for nearly four decades. This technique is not yet universally embraced by strabismus surgeons, especially in pediatric patients. The aim of this study is to describe and evaluate the application of the adjustable suture with pull-string technique in pediatric patients.

METHODS:

A retrospective medical record review was conducted for patients aged 18 years and under who received adjustable suture strabismus surgery using short tag sliding noose with pull-string technique. For the analysis, the patients were arbitrarily divided into three age groups: 6 years and younger, between 6 and 12 years, and 12 years and older. Patients were examined at 1 week and 1, 3, and 6 months after surgery.

RESULTS:

A total of 123 patients were enrolled in this study. The mean age at the time of surgery was 9.4 years, ranging from 0.7 to 18.4 years. Eighteen (14.6%) patients required adjustment and 105 (85.4%) patients did not require adjustment. The average follow-up was 10.2 months (range, 1–48 months). At their final postoperative follow-up, 93 of 123 (75.6%) patients were within 10 prism diopters of orthophoria. The success rates were 77.6% (66/85) in exotropia patients and 71.1% (27/38) in esotropia patients. The success rates were 76.4% (84/110) for those who receive the procedure as primary surgery and 69.2% (9/13) for those who receive the procedure as reoperative surgery. Of the 18 patients who required adjustment, 16 (88.9%) patients were successful. Of the 105 patients who did not require adjustment, 77 (73.3%) patients were successful.

CONCLUSION:

This study showed that the pull-string technique provided similar success rate compared to those reported in literature in pediatric patients. The pull-string technique is developed to simplify the postoperative adjustments. Many surgeons encounter difficulties to handle the postoperative adjustments, especially when they need to retrieve the buried subconjunctival adjustable sutures. The obstacles are reduced with the aid of pull string. Using the pull-string technique, the surgeon can perform adjustable suture surgeries in any age group with confidence.

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.

Outcomes of adjustable strabismus surgery in an Irish University Hospital

PURPOSE

Strabismus surgery aims to improve binocular vision, reduce diplopia, and enhance cosmesis. Adjustable strabismus procedures have been developed as a means of tackling unpredictability in some post-operative results. The purpose of the study was to compare the effectiveness of adjustable and non-adjustable squint procedures in the treatment of strabismus.

METHODS

We analyzed adjustable or non-adjustable squint surgery undergone in our Irish locality by retrospectively studying 27 consecutive patients at Mater Misericordiae University Hospital, Dublin.

RESULTS

There was no significant difference (p = 0.519) in the mean post-operative horizontal deviation between the adjustable group (mean = 11.6 PD) and the non-adjustable group (mean = 15.3 PD). We found that adjustable procedures resulted in a trend (p = 0.050) towards a greater mean horizontal effect per muscle (18.9 PD per muscle) than non-adjustable procedures (mean 9.7 PD). We went on to analyze the adjustable group in order to determine the impact on outcome in those patients in whom their adjustable sutures were manipulated postoperatively. Of the 11 patients who underwent adjustable procedures, 6 subsequently had adjustments made as planned and 5 did not require adjustment. Those patients who had their sutures adjusted demonstrated a smaller mean post-operative deviation (8.5 PD) than those patients in whom their suture was not adjusted (mean = 16.3 PD).

CONCLUSION

Our study displays a trend that adjustable procedures are more effective in terms of the mean horizontal effect per muscle operated, and is a novel way of reporting effectiveness of strabismus procedures.

Strabismus surgery among Medicare beneficiaries: imputed rates of reoperation in the same calendar year

PURPOSE

To compare strabismus surgery reoperation rates in a large national database of provider payments when the adjustable-suture technique was available and not available.

MATERIALS AND METHODS

Fee-for-service payments to Medicare providers for horizontal (CPT 67311) and vertical (CPT 67314) strabismus surgery in 2012 were analyzed to identify payments for reoperations in the same calendar year. The adjustable-suture technique was considered to be available to the patient if the patient's surgeon billed for adjustable sutures during the year. We determined the association of reoperation with the availability of the adjustable-suture technique and with surgeon volume.

RESULTS

Patients having horizontal muscle surgery had a rate of reoperation in 2012 of 4.1% (15 of 364 patients) when the adjustable technique was available, compared with 7.1% (77 of 1,082 patients) when the adjustable technique was not available (P = 0.047). Patients having vertical muscle surgery had a rate of reoperation in 2012 of 4.1% (8 of 196 patients) when the adjustable technique was available, compared with 8.3% (38 of 458 patients) when the adjustable technique was not available (P = 0.07). Having surgery in a high-volume surgical practice was not reliably associated with reoperation rates.

CONCLUSIONS

For patients having strabismus surgery, the availability of the adjustable-suture technique was associated with a lower reoperation rate in this large national database (compared with patients for whom the adjustable technique was not available). The difference was statistically significantly different from zero for horizontal muscle surgery but not for vertical muscle surgery.

Bilateral lateral rectus muscle recession for the convergence insufficiency type of intermittent exotropia

PURPOSE

To evaluate the surgical efficacy of bilateral lateral rectus recession (BLRR) for intermittent exotropia with convergence insufficiency (CI-type X[T]).

METHODS

The medical records of patients with CI-type X(T) who underwent BLRR on adjustable suture from January 2011 to March 2014 were retrospectively reviewed. Ocular alignment and sensory status were evaluated pre- and postoperatively for each patient. The mean distance and mean near deviation, before and after surgery, as well as the mean near-distance difference, were compared. Success was defined as postoperative alignment of esophoria/tropia of ≤5(Δ) and exophoria/tropia of ≤8(Δ) at distance.

RESULTS

A total of 25 patients were included. The mean exodeviation was significantly reduced, from 32.5(Δ) preoperatively to 0.08(Δ) postoperatively (P < 0.001) at distance and from 45(Δ) preoperatively to 2.4(Δ) (P < 0.001) postoperatively at near. The mean near-distance difference was reduced from 16(Δ) preoperatively to 2(Δ) postoperatively (P < 0.01). Of the 25 patients, 21 (84%) obtained successful motor alignment, 2 had recurrent exodeviation of ≥10(Δ) at distance, and 2 had overcorrected esotropia with deviation angles of >8(Δ).

CONCLUSIONS

In this cohort of patients, bilateral lateral rectus recession using an adjustable suture technique successfully treated CI-type X(T).

Slipping the knot: a comparison of knots used in adjustable suture strabismus surgery

PURPOSE

To evaluate the frictional force created by different knots used in adjustable suture strabismus surgery.

METHODS

To allow the simulation of strabismus surgery suture tying methods a model using 6-0 polyglactin 910 suture was created. Three different knots were evaluated: (1) the sliding noose knot with a double wrap of suture, (2) the cinch knot with a single throw on both sides of the pole suture, (2) and a single-throw square knot. (Bow-tie knots were not included.) A digital force meter was used to measure the force (gram-force [gf]) required to overcome the static friction created by the knot. Each simulation was repeated with new suture material 5 times and the force required after subsequent repositioning was also recorded.

RESULTS

The force to overcome static friction of the sliding noose knot was 240 gf [95% CI, 187-284 gf]; of the cinch knot, 150 gf [95% CI, 123-167 gf]; and of the square knot, 110 gf [95% CI, 95-121 gf]. Subsequent movement of each knot along the same suture required progressively less force, with the sliding noose maintaining the most static friction.

CONCLUSIONS

The sliding noose knot generates the most frictional force and also maintains the most friction after subsequent repositioning. Important consideration should be given to multiple repositioning movements, because the force required for each subsequent repositioning decreases.

Strabismus Surgery Reoperation Rates With Adjustable and Conventional Sutures

PURPOSE

To determine the association of strabismus surgery reoperation rates with adjustable or conventional sutures.

DESIGN

Retrospective cross-sectional study.

METHODS

setting: Review of a large national private insurance database.

STUDY POPULATION

Adults aged 18-89 having strabismus surgery between 2007 and 2011.

INTERVENTION

Adjustable vs conventional suture strabismus surgery.

OUTCOME MEASURE

Reoperation rate in the first postoperative year.

RESULTS

Overall, 526 of 6178 surgical patients had a reoperation (8.5%). Reoperations were performed after 8.1% of adjustable suture surgeries and after 8.6% of conventional suture surgeries (P = .57). Of the 4357 horizontal muscle surgeries, reoperations were performed after 5.8% of adjustable suture surgeries, and after 7.8% of conventional suture surgeries (P = .02). Of the 1072 vertical muscle surgeries, reoperations were performed after 15.2% of adjustable suture surgeries and after 10.4% of conventional suture surgeries (P = .05). Younger age (18-39 years) was associated with a lower reoperation rate (P ≤ .02). The significant multivariable predictors of reoperation for horizontal surgery were adjustable sutures (odds ratio [OR] 0.69, 95% confidence interval 0.52-0.91), monocular deviation (OR 0.64), complex surgery (OR 1.63), and unilateral surgery on 2 horizontal muscles (OR 0.70, all P ≤ .01). Adjustable sutures were not significantly associated with reoperation rates after vertical muscle surgery (multivariable OR 1.45, P = .07).

CONCLUSIONS

Adjustable sutures were associated with significantly fewer reoperations for horizontal muscle surgery. Adjustable sutures tended to be associated with more reoperations for vertical muscle surgery, but this observation was not statistically significant in the primary analysis after controlling for age.

Instructions to Patients and Families Following Strabismus Surgery

PURPOSE

To analyze postoperative instructions provided to patients and families after strabismus surgery.

METHODS

In April 2012, a 12-question electronic survey was sent to all members of the American Association for Pediatric Ophthalmology and Strabismus (AAPOS) regarding their instructions to patients undergoing strabismus surgery. The questions specifically addressed patients’ daily activities, such as their resumption of school and work, sports, swimming, normal showering and bathing, and contact lens use.

RESULTS

One hundred two responses were completed; 96% were from pediatric ophthalmologists regularly performing strabismus surgery. Participation was greater by North American members (86%) and respondents with more than 10 years of experience (75%). Fifty percent of the respondents advised patients to resume normal showering and bathing 24 hours after surgery. Conversely, respondents recommended that children wait 3 to 4 days before resuming schoolwork (52%) and at least 2 weeks before playing in a sandbox (47%). Furthermore, respondents indicated that patients should refrain from participating in sports-related activities for at least 1 week (43%) and should not go swimming for at least 2 weeks (56%). Finally, 47% advised their patients not to wear contact lenses for 2 weeks after surgery.

CONCLUSIONS

Overall, the responses indicated a high regard among AAPOS members for promoting normal healing and prevention of infection and other postoperative complications; however, certain trends, such as the recommendation regarding normal showering, may intimate a lack of further infection prevention.

Vision concerns after mild traumatic brain injury

OPINION STATEMENT

Mild traumatic brain injury (mTBI) can manifest with visual dysfunction including deficits in accommodation, vergence movements, versions, and field of vision as well increased photosensitivity and a decline in ocular and overall health. Patients with incomitant strabismus should be referred to an ophthalmologist for intervention. Patients with mTBI who experience photosensitivity, or deficits in accommodation, versions, vergences, or field of vision may benefit from vision rehabilitation. These therapies may include spectacles with tinting and a variety of prism combinations. Patients with chronic visual dysfunction following mTBI may benefit from occupational, vestibular, cognitive, and other forms of physical therapy.

Pull-string technique for recovering subconjunctival short-tag noose adjustable sutures

The "short tag noose" technique is used to adjust sutures after strabismus surgery. The pole and noose sutures are buried below conjunctiva for possible use in later adjustment; however, they are not always easily recoverable. We report a "pull string" modification of the technique that permits retrieval of the pole and noose sutures without the need to enlarge the conjunctival wound or explore the subconjunctival space. If suture adjustment proves unnecessary, the pull string can be removed effortlessly under topical anesthesia, even in uncooperative children.

Predictors of Good Motor and Sensory Outcomes Following Strabismus Surgery for Patients with Third Nerve Palsies

Strabismus from third nerve palsy (3NP) is difficult to treat. Our goal was to explore factors associated with successful surgical outcomes in 3NP. Institutional records of all adult patients (>18 years) from 1988 to 2012 with 3NP who underwent strabismus surgery or botulinum toxin injections were retrospectively reviewed. Success was defined as absence of diplopia, vertical deviation ≤2 prism dioptres (PD), and horizontal deviation ≤10 PD. Fifty-six patients from four surgeons were included. Thirty (54%) were female; mean age was 48 (range: 20-80). Forty-four (79%) had unilateral 3NP; 9 (16%) had other ocular motor nerve palsies. 3NP were complete in 24 (43%). Underlying aetiology was idiopathic/microvascular in 5 (9%), traumatic in 13 (23%), neoplastic in 12 (21%), aneurysmal in 10 (18%), and other central nervous system related in 16 (29%). Trauma was associated more frequently with aberrant regeneration than other aetiologies: 9/13 (69%) versus 4/43 (9%) (p < 0.01). Ten patients (18%) had >1 surgery. Surgical success was achieved in 28/56 (50%). Success rate was unaffected by aetiology, degree of palsy, pupillary involvement, presence of aberrant regeneration, or number of other cranial nerves involved. However, adjustable sutures were used in 27 patients (48%), and there was a trend toward higher success rates when adjustable versus nonadjustable sutures were used (63% versus 38%; p = 0.06). Unlike with sixth nerve palsies, the aetiology and degree of 3NP does not appear to affect the success rates or number of procedures performed. Strabismus surgeries for 3NP with adjustable sutures may be associated with better outcomes.

Functional and Motor Outcomes of Strabismus Surgery for Chronic Isolated Adult Sixth Nerve Palsy

Abducens nerve palsy is the most common acquired ocular motor nerve palsy in adults. Chronic cases of abducens palsy often require surgical intervention to relieve disabling diplopia. The goal of this study was to identify factors associated with surgical outcomes in isolated abducens palsy. Medical records of all adult patients from 1988 to 2012 with abducens palsies who underwent strabismus procedures were retrospectively reviewed. Motor alignment, extraocular motility, and sensory outcomes were recorded. Success was defined as absence of diplopia without prisms or face turn, vertical deviation ≤2 prism dioptres (PD), and horizontal deviation ≤10 PD. Eighty-one patients (age range: 20-86 years) met inclusion criteria. Success was achieved in 58% of patients. Final success rates for abducens palsy were 50% for neoplastic, 59% traumatic, 57% for microvascular/unknown, and 67% for other central nervous system causes (p > 0.05). Patients with an underlying neoplastic or traumatic aetiology required more than one strabismus procedure more often than those with microvascular/idiopathic or other central nervous system causes (48% vs. 24%; p = 0.03). For complete abducens palsies, patients who underwent Hummelsheim-type procedures had a higher success rate than those who underwent a full-tendon vertical rectus muscle transposition. (78% versus 35%; p = 0.049). Success rates for strabismus procedures in patients with abducens palsies are similar across all aetiologies. Frequency of re-operation is higher among those patients with neoplastic or traumatic aetiologies for their abducens palsies. Hummelsheim-type procedures have a higher success rate for complete abducens palsies than full-tendon vertical rectus transpositions.

A survey of outcome of adjustable suture as first operation in patients with strabismus

Background:

Adjustable suture used for years to improve the outcome of strabismus surgery. We surveyed outcome of our patients with strabismus who underwent adjustable suture.

Materials and Methods:

This retrospective study was performed at Ophthalmology Centre of Feiz Hospital in Isfahan on 95 participants that candidate for adjustable suture strabismus surgery. Patients were divided into three age groups: Under 10 years, 10-19 years, and 20 years and over. Outcome of adjustable suture surgery consequence of residual postoperative deviation was divided into four groups: Excellent, good, acceptable, and unacceptable.

Results:

Out of 95 patients studied, 51 (53.7%) were males and 44 (46.3%) were females. The mean of deviation angles were 53.8 ± 17.9 PD (Prism dioptres) in alt XT, 44.5 ± 12 PD in alt ET and 52 ± 13.5 PD in const ET, 47.1 ± 13.1PD in cons XT, respectively. There was no significant difference between the groups (P = 0.051). Results of surgery were in 38 patients (40%) excellent, in 31 patients (32.6%) good, in 19 patients (20%) acceptable, and in 7 patients (7.4%) unacceptable. Seven (7.4%) patients required reoperation.

Conclusions:

In the present study, the frequency of re-operation was much lower than other similar studies (7.4% vs. 30-50%). This suggests that the adjustable technique that used in our study can be associated with lower reoperation than other adjustable techniques used in the other similar studies.

Adjustable sutures in children

Although adjustable sutures are considered a standard technique in adult strabismus surgery, most surgeons are hesitant to attempt the technique in children, who are believed to be unlikely to cooperate for postoperative assessment and adjustment. Interest in using adjustable sutures in pediatric patients has increased with the development of surgical techniques specific to infants and children. This workshop briefly reviews the literature supporting the use of adjustable sutures in children and presents the approaches currently used by three experienced strabismus surgeons.

Postoperative drift in patients with thyroid ophthalmopathy undergoing unilateral inferior rectus muscle recession

BACKGROUND

Extraocular muscles of patients with thyroid ophthalmopathy (TO) may respond differently to strabismus surgery than those of other strabismic patients. This study reports postoperative alignment changes in patients with TO compared with patients with non-restrictive strabismus following unilateral inferior rectus muscle recession (IRR).

METHODS

We reviewed records of patients with and without TO who underwent unilateral IRR. Group A had adjustable muscle sutures, while Group B had permanent or semi-adjustable sutures. Controls were patients undergoing adjustable unilateral IRR for other indications.

RESULTS

Mean preoperative hypotropias were 17 ± 9, 21 ± 7, and 11 ± 4 PD for groups A (n=13), B (n=14), and controls (n=19), respectively. Postoperative day one (POD1) measurements after adjustment were 1.2 ± 2.5, 3.7 ± 4.9, and 0.3 ± 2.4 PD, respectively, representing overall undercorrections in all cases (the preoperative deviation was given a positive (+) value and overcorrections were deemed negative (-) deviations). Dose response from linear regression analysis of thyroid patients compared with control patients for IRR was 3.26 PD/mm (SE 0.18) vs 2.38 PD/mm (SE 0.18) (p=0.001). Mean final measurements were -0.7 ± 5.6 (overcorrection), 2.7 ± 5.7, and 1.7 ± 5.7 PD of hypotropia, respectively. Final overcorrections occurred in 23%, 14%, and 16% of patients, for adjustables, permanent sutures, and control subjects, respectively. Drifts from POD1 measurements after adjustment to final measurements were -1.9 ± 4.3, -1.0 ± 4.6, and 1.4 ± 5.9 PD respectively (p=0.05 for comparison between Group A and controls).

CONCLUSIONS

TO patients with adjustable sutures drift toward postoperative overcorrection.

Rectus muscle plication using an adjustable suture technique

PURPOSE

Rectus muscle plication is an alternative muscle-strengthening procedure to rectus muscle resection. Possible advantages of rectus muscle plication include a lower risk of "lost" muscles and anterior segment ischemia.

METHODS

This was a retrospective case series describing a surgical procedure for rectus muscle plication using an adjustable suture technique that can be used on any of the four rectus muscles.

RESULTS

A total of 5 adult patients underwent adjustable suture plication procedures. Of these, 2 patients required suture adjustment postoperatively. At the final follow-up visit, all the patients maintained satisfactory ocular alignment within 6(Δ) of orthotropia for horizontal deviations and 2(Δ) of orthotropia for vertical deviations. Diplopia was eliminated in all cases with preoperative diplopia. There were no postoperative complications or unexpected shifts in ocular alignment.

CONCLUSIONS

Rectus muscle plication using this adjustable suture technique may serve as an alternative to rectus muscle resection and may be particularly useful in patients who are at risk for anterior segment ischemia or those in whom a shorter anesthesia time is recommended.

Loop suture technique for optional adjustment in strabismus surgery

Purpose:

To describe a loop suture technique that allows intraoperative conjunctival closure and later optional suture adjustment in strabismus surgery in uncooperative patients.

Materials and Methods:

This retrospective case series comprised 25 patients. After a recessed or resected horizontal muscle was secured to the sclera with a primary suture suspended back 2 mm, a second loop suture was passed through the body of the muscle and under the primary suture knot. The loop suture could be removed later while the patient was awake, or it could be tied to advance the muscle. Success was defined as a residual deviation of 10 prism diopters (PD) or less at 2 months postoperatively.

Results:

In the study cohort, 20 patients had successful alignment at 2 months (80%). Six patients (24%) underwent postoperative suture tightening by the loop technique, and each muscle affected the alignment an average of 7.7 PD (±3.8 PD). No patients underwent a reoperation within the first 2 months. One patient had a pyogenic granuloma (4%).

Conclusions:

The loop suture technique permits optional postoperative tightening of muscles and avoids sedation in children or uncooperative patients not requiring adjustment.

Long-term follow-up of strabismus surgery for patients with ocular myasthenia gravis

BACKGROUND

Patients with ocular myasthenia gravis (OMG) may develop strabismus and diplopia. We completed a retrospective observational case series to evaluate long-term surgical outcomes in patients with OMG.

METHODS

The medical records of all patients with OMG who underwent strabismus surgery with at least 6 months of postoperative follow-up were reviewed. Nine patients met the study inclusion criteria. The main outcomes, including ocular alignment, number of surgeries, and sensory status were evaluated.

RESULTS

Of these patients, initially 2 had horizontal strabismus alone, 3 had vertical strabismus alone, 3 had both vertical and horizontal strabismus, and 1 patient had vertical and torsional strabismus. The length of preoperative stability was 2.0 ± 2.5 years (range: 0.1-8.0 years). The mean preoperative horizontal and vertical deviations were 40.5 ± 32.5 prism diopters (PD; range: 0-90 PD) and 25.6 ± 36.7 PD (range: 0-120 PD), respectively. The average length of the follow-up after the first surgery was 5.7 ± 4.2 years (range: 0.7-10.6 years). Four patients (44%) underwent 2 operations. For patients requiring a second operation, the time to second operation was 2.3 years (range: 0.4-5.0 years). Six patients (67%) were within 10 PD of orthotropia at distance in primary position at the final visit. Five patients (55%) had single vision after their surgeries.

CONCLUSION

Strabismus surgery can achieve good long-term binocular alignment in patients with OMG.

Determinants of ocular deviation in esotropic subjects under general anesthesia

PURPOSE

The authors attempted to identify the determinants of ocular deviation in a population of patients with esotropia under general anesthesia.

METHODS

Forty-one patients with esotropia were included. Horizontal ocular deviation was evaluated by the photographic Hirschberg test both in the awakened state and under general anesthesia before surgery. Changes in ocular deviation were measured and a multivariate analysis was used to assess its clinical determinants.

RESULTS

The mean age (± standard deviation [SD]) of study subjects was 13 ± 11 years and 51% were females. The mean spherical equivalent refraction of the right eye was 2.44 ± 2.50 diopters (D), with no significant difference between eyes (P = .26). The mean ocular deviation changed significantly, from 33.5 ± 12.5 prism diopters (PD) at preoperative examination to 8.8 ± 11.4 PD under general anesthesia (P = .0001). The changes in ocular deviation positively correlated with the pre-operative ocular deviation (correlation coefficient r = 0.59, P = .0001) and negatively correlated with patient age (correlation coefficient r = -0.53, P = .0001). These two determinants remained significant after multivariate adjustment of the following variables: preoperative ocular deviation; age; gender; spherical equivalent refraction; and number of previous strabismus surgeries (model r(2) = 0.49, P = .0001).

CONCLUSIONS

The ocular position under general anesthesia was reported as a key factor in the surgical treatment of subjects with esotropia; therefore, its clinical determinants were assessed. The authors observed that preoperative ocular deviation and patient age were the main factors that influenced the ocular position under general anesthesia.