Muscle Surgery Research Articles

Physiotherapists working with pessaries

Pessaries and the physiotherapy profession have evolved over the past 10 years, and pelvic health physiotherapists can now prescribe vaginal pessaries. Pelvic, Obstetric and Gynaecological Physiotherapy (POGP) is developing ways to support members with these skills. Globally, up to 50% of women will suffer from pelvic organ prolapse (POP) (Carroll et al. 2022), and this condition costs the UK National Health Service £45 million every year (PCWHF 2019). The most common symptom is a vaginal bulge. The National Institute for Health and Care Excellence guidelines recommend either doing nothing, or pelvic floor muscle exercises (PFMEs), vaginal pessaries or surgery (NICE 2019). Pessary services are provided in dedicated clinics, usually in general practice or secondary care. There has been an increase in physiotherapists delivering pessary care over the past decade: in 2013, it was reported that 1.4% were part of the pessary workforce compared to 5% in 2020 (Bugge et al. 2013; Brown et al. 2021). Currently, ineffective patient pathways, poor service provision and lack of training are barriers to treatment. Poorly designed patient pathways are frustrating, and women are often required to return to primary or secondary care to get a referral to a pessary clinic. Physiotherapists are well placed to offer a pessary alongside PFMEs since it is part of the range of conservative treatment options. They also build strong a rapport with their patients because of the therapeutic nature of the treatment sessions, and typically, offer longer appointments than postnatal period. A prospective multicentre trial demonstrated the acceptability of and compliance with using a pessary immediately after childbirth irrespective of any pelvic floor dysfunction or mode of delivery (Baessler et al. 2019). The majority of women used the pessary to treat the symptoms of POP. Further work is required to investigate pessary use and the prevention of pelvic floor dysfunction in this cohort of women. The results of the TOPSY [Treatment Of Prolapse with Self-care pessarY] trial (Hagen et al. 2023) highlighted that pessary self-management is cost-effective and reduces complications. This is excellent news because physiotherapists are well placed to teach women pessary self-management because of: generally longer appointments; and the well-established rapport built up over time while teaching PFMEs. Despite women reporting that pessary use during exercise relieves their symptoms, this is an under-researched area. The impact of exercise on POP, and whether there are any protective factors involved that prevent its progression, are not fully understood. There also remains a gap in the evidence with regard to the use of PFMEs and vaginal pessaries. Research proposals are currently in development to address this. A pessary course is being developed by POGP, and this will be launched in 2024 alongside a mentoring programme as part of the pessary accreditation scheme jointly written with the United Kingdom Continence Society. Further governance documents have been created by the Physiotherapists Working with Pessaries subgroup of POGP, including a standard operating procedure, emergency out-of-hours statement, note proformas and template letters (POGP 2024).

Corneal Curvature Change After Strabismus Surgery: An Experience from a Single-academic Center

Objective: This study aimed to explore corneal curvature changes following strabismus surgery using a quadric surface fitting model to address ocular misalignment. Material and Methods: In this prospective cross-sectional study, 54 completed cases (84 eyes) of patients aged 6–60 years old (mean 10 years old) undergoing horizontal rectus muscle surgery were examined using placido-based keratometry with the Oculus Keratograph 5M system. Data on corneal curvature were collected one week pre-operation, and again one week, one month, and three months post-operation. Asphericity in the vertical meridian (Qy) and horizontal meridian (Qx), and surgical-induced astigmatism (SIA) were calculated. Results: The 84 eyes included were categorized into three groups: horizontal muscle surgeries, oblique muscle surgery, and combined horizontal and oblique muscle surgeries. Significant corneal prolation (steep central, flat peripheral) was revealed in the vertical meridian (Qy) at 3 months postoperatively for lateral rectus (LR) recession in the first group (p < 0.001), and the mean SIA was 0.45 D (95% CI: 0.35–0.56 D). A similar effect was seen in the vertical meridian of the third group (p < 0.01), with a mean SIA at 3 months of 0.27 D (95% CI: 0.23–0.32 D). Conclusion: Lateral rectus muscle recession induces corneal vertical prolation for up to 3 months post-operation. Surgeons are thus advised to re-evaluate refraction and defer contact lens refitting, refractive surgery, and intraocular lens calculations for at least 3 months after the procedure.

One- vs Two- vertical muscle surgery in the management of unilateral superior oblique muscle palsy with hypertropia over 20 PD

ABSTRACT Purpose: To compare the surgical outcomes of One- versus Two-vertical muscle surgery in patients with unilateral superior oblique muscle palsy (SOP) with primary position hypertropia (HT) over 20 PD. Patients in Group 1 underwent inferior oblique anterior transposition plus resection (IOATR), while patients in Group 2 underwent inferior oblique anterior transposition (IOAT) along with contralateral inferior rectus (IR) recession. Methods: Medical data of all SOP patients treated by either procedure from 2000 to 2023 in our strabismus center were recruited. We compared surgical outcomes between Group 1 and Group 2 by analyzing HT correction, rate of under-correction, and over-correction. Results: The study included 33 patients in Group 1 and 23 in Group 2. Both groups were similar in age, sex, etiology, affected side, diplopia, and head tilt. Group 2 achieved higher HT correction in all measured gazes. Group 1 had a higher risk of under-correction (18.18% in Group 1 vs 8.69% in Group 2) while Group 2 had a higher rate of over-correction (21.73% vs 0% in Group 1). Conclusion: In patients with severe unilateral SOP, Two-vertical muscle surgery achieved higher amounts of HT correction in all gazes despite a significantly higher risk of over-correction.

Exploring physiotherapy strategies in arthrogenic muscle inhibition: A scoping review

Arthrogenic muscular inhibition (AMI) is the presynaptic continual reflex inhibition of the surrounding muscles. It is a defensive reaction that lowers motor neuron activity to prevent further damage; however, if it persists, it can cause muscle atrophy and weakness, which can cause functional limitations. It usually involves quadriceps muscle post knee injuries and surgeries. Though it can be appreciated at any joint post injury or surgery like shoulder , elbow and ankle. Recent studies shows that post injury or surgery, tissues respond by reflex inhibition mechanism and is unnoticed by many therapists. The aim of this review is to analyse the various approaches available in the physiotherapy rehabilitation for treating AMI of any joint and to know the best treatment approach to be used for optimising the effects of AMI. Total of 37 articles were considered to identify the different outcomes and interventions used in treating AMI. In conclusion, Effective physiotherapy interventions are necessary to address AMI and enhance joint function and muscle activation. NMES, cryotherapy, and certain strengthening exercises are a few examples of interventions that can help get past the neural inhibition limiting muscle activation surrounding an injured joint. The implementation of early physiotherapy interventions is essential for preventing muscle atrophy and regaining normal movement patterns. In order to advance patient rehabilitation and maximize healing and functional outcomes, a customized protocol with particular demands is required.

Investigation of the effects of single and two-muscle horizontal rectus surgeries on macular microvasculature.

To investigate the changes in posterior segment hemodynamics caused by horizontal rectus muscle surgeries using the optic coherence tomography angiography (OCTA). Patients who underwent at least one horizontal rectus recession, resection, or combination surgery were included. The patients were evaluated with an OCTA preoperatively and 30days postoperatively. Postoperative changes in superficial capillary plexus (SCP)-vessel density (VD), deep capillary plexus (DCP)-VD, foveal avascular zone (FAZ) area and choriocapillaris (CC)-flow area parameters were examined. The mean differences (Δ) for the parameters in which significant changes were detected in the whole operated eyes group were compared between the single- and two-muscle surgery groups. Twenty-five eyes of 24 patients with an average age of 16.40 ± 6.75years (5-29) were included. Of the eyes, 10 underwent single muscle recession surgery. Two-muscle surgeries were performed in 15 eyes. SCP-VD in the superior parafoveal region increased significantly postoperatively (53.23 ± 4.11% vs. 54.54 ± 3.67%, p = 0.032). For DCP-VD, there was a statistically significant increase in all zones, except the superior hemisphere and fovea regions (p < 0.05 for all). FAZ area did not change significantly (p = 0.207). There was a significant increase in the CC-flow area (2.171 ± 0.146 mm2 vs. 2.232 ± 0.115 mm2, p = 0.013). There was a significant difference between the two groups only for the Δ SCP-VD/parafovea superior value (-0.62 ± 0.98 vs. 1.57 ± 3.07, p = 0.019). Conventional horizontal rectus muscle surgeries may cause alterations in posterior segment hemodynamics. The number of muscles incised does not seem to greatly affect the magnitude of changes that occur. What is known • After conventional horizontal rectus muscle surgeries, the anterior ciliary arteries are not recanalized, instead, anterior segment blood flow is maintained by increasing the flow in the long posterior ciliary arteries. • Previous studies using Doppler ultrasonography have shown increased flow in the ophthalmic artery, central retinal artery and long posterior ciliary arteries. What is new • In this study, significant increases were observed in superficial and deep capillary plexus-vessel density and choriocapillaris-flow area parameters in the first postoperative month with optic coherence tomography angiography device. • Hemodynamic increases in both retinal and choroidal vasculature were detected in the early period after conventional horizontal rectus muscle surgeries. • The number of muscles incised does not seem to greatly affect the magnitude of changes that occur.

Reoperation for congenital ptosis: characteristics, success rates, and predicting factors

ObjectiveReoperation for congenital ptosis has added morbidity. The purpose of the current study was to examine the risk for redo ptosis surgery in patients with congenital ptosis, as well as to find predictive factors for reoperation. MethodsThis is a retrospective, cohort study. Analysis of all patients with congenital ptosis who underwent their first ptosis correction surgery between 2012 and 2021 at Sheba Medical Center was performed. ResultsSixty patients (36 male and 24 female) underwent ptosis surgery for congenital ptosis Twenty nine patients (48.33%) underwent frontalis sling (FS), 13 patients (21.67%) underwent levator muscle (LM) surgeries, 9 patients received levator resection (LR), 4 patients received external levator advancement (LAA), and 18 patients (30%) underwent Müller's muscle-conjunctival resection (MMCR). Eighteen patients (30%) underwent a second ptosis surgery. The unadjusted risk of second ptosis surgery was almost four-fold among males with ptosis relative to females with ptosis (HR, 3.90; 95% CI, 3.67-547; p = 0.033) and higher among younger individuals (HR, 4.23; 95% CI, 3.33-5.62; p = 0.042). Older age was protective against the risk of second ptosis surgery (adjusted OR, 0.50; 95% CI, 0.21-0.60; p < 0.001), whereas male sex was associated with an increased likelihood of second ptosis surgery (adjusted OR, 3.33; 95% CI, 1.64-3.98; p < 0.001). ConclusionsAn increased risk of failure of the first surgery was found among male patients, younger patients, and patients with more severe ptosis before the first surgery. Awareness of those factors is beneficial for clinicians and parents.

Medial Rectus Disinsertion for the Management of Large-Angle Sensory Esotropia.

Background and Objectives: The aim of the report is to report the outcomes of the medial rectus (MR) disinsertion procedure for the management of large-angle esotropia (ET) patients. Materials and Methods: This is a retrospective case series of patients with large-angle ET who underwent an MR disinsertion procedure between March 2012 to April 2022. The procedure happened accidentally during muscle surgery. The demographic and clinical data, including sex, age, visual acuity, pre- and postoperative angle of strabismus, duction limitations, results of intraoperative forced duction tests, and follow-up duration were collected from medical records. Results: Five patients were enrolled in this study. The mean age was 62.2 ± 9.8 years, and the mean follow-up was 24.8 ± 8.7 months. The ET at the primary position of gaze was 92.0 ± 17.9 prism diopters (PD) before MR disinsertion and 38.0 ± 29.5 PD after MR disinsertion only. Abduction deficiency was -4 before after MR disinsertion, which improved to -1 at the last follow-up. Conclusions: The results of MR disinsertion were not as frustrating as anticipated. MR disinsertion may be considered in patients with large-angle sensory ET who refuse surgery on the opposite eye.

Outcomes and Factors Associated with Successful Strabismus Surgery for Abducens Nerve Palsies: A Retrospective Study and Literature Review.

Several studies reported surgical outcomes for abducens nerve palsy, but information on factors that affect treatment success remains lacking. These factors are crucial for developing a treatment plan and providing disease counseling. This study aimed to investigate the outcomes of strabismus surgery for abducens nerve palsy and determine the factors that influence its success, including a review of relevant literature. This retrospective analysis included abducens nerve palsy cases, focusing on surgical interventions and relevant patient data, at the outpatient clinics of Phramongkutklao Hospital from April 1, 2012, to April 30, 2022. A relevant literature review included the surgical success rate and factors that influence surgical outcomes. This study enrolled 32 patients, including 19 with partial and 13 with complete abducens nerve palsy. The overall success rate of strabismus surgery was 78.1%. Trauma was the leading cause of abducens nerve palsy in this population (28.13%). Fisher's exact and Mann-Whitney U-tests revealed that shorter abducens nerve palsy onset and smaller preoperative angle were significantly associated with successful surgical outcomes of strabismus surgery among the groups. In contrast, subgroup analysis revealed that only preoperative smaller angles were significantly associated with good surgical outcomes in horizontal strabismus surgery. However, the vertical rectus muscle transposition group demonstrated no significant factors. The literature review revealed that the success rate of surgery in abducens nerve palsy was 25%-82.6% for horizontal rectus muscle surgery and 46.2%-91% for rectus muscle transposition. The surgical success rate for abducens nerve palsy reached 78.1%, including 78.95% for partial and 76.92% for complete abducens nerve palsy. Notably, a shorter onset preceding surgery and a smaller preoperative angle significantly correlated with successful surgical outcomes one year postoperatively.

Graves' orbitopathy as the cause of diplopia in old age-Differences between young and old

Endocrine orbitopathy (EO) is an autoimmune disease mostly associated with a disease of the thyroid gland, which leads to inflammation, adipogenesis and fibrosis. The severity of EO can vary greatly between individuals, which makes it difficult to exactly predict the natural course of the disease; however, this is important to be able to individually adapt the treatment. The aim of this study was to compare the clinical features, course, treatment and prognosis for patients with EO under 50 years old with older patients. The results of the study with a focus on motility are presented in this special issue. The hospital records of a randomly selected sample of 1000 patients from the EO databank in Essen (GODE), which includes 4260 patients, were analyzed. The patients were divided into two groups: group 1 ≤50 years and group 2 >50 years. Only patients with complete data sets were included in the statistical analyses. Younger patients (n = 484) presented significantly more frequently with milder EO (53% vs. 33%, p < 0.0001), whereas older patients (n = 448) more frequently suffered from moderate or severe forms (44% vs. 64%, p < 0.0001). Older patients showed more severe strabismus, motility and clinical activity scores (5.9 vs. 2.3 prism diopters, PD/310° vs. 330°, both p < 0.0001, CAS 2.1 vs. 1.7, p = 0.001). Proptosis and the occurrence of optic nerve compression showed no significant differences between the groups (3% each). Multiple logistic regression showed that the necessity for a second eye muscle surgery was most strongly associated with a previous decompression (OR = 0.12, 95 % CI 0.1-0.2, p < 0.0001), followed by orbital irradiation and age. In summary, younger patients with EO presented with milder clinical features, such as a lower rate of restrictive motility disorders and weaker expression of signs of inflammation. Therefore, older patients needed steroids, irradiation, eyelid and eye muscle surgery more frequently; however, the risk of dysthyroid optic neuropathy and the necessity of a second eye surgery were not or only slightly associated with age.

Perioperative variables associated with emergence delirium in children following strabismus surgery: A five-year retrospective single-center cohort study

ABSTRACT Background Emergence Delirium (ED) is common among children. Several factors have been linked to ED related to patient characteristics, anesthesia, or the type of surgery. Strabismus surgery has been associated with the development of ED. The aim of this study was to determine the perioperative variables associated with ED after strabismus surgery in children. Methodology A retrospective cohort study of children who underwent strabismus surgery from January 2018 to December 2022 was conducted. Data on factors leading to ED, including patient characteristics, preoperative anxiety, postoperative pain, surgery-related characteristics anesthesia-related characteristics, were analyzed. Emergence delirium was assessed using the Pediatric Anesthesia Emergence Delirium (PAED) scale. Results Three-hundred-and-thirty-six children were included in the analysis. Fourteen percent of patients developed ED. Predictors of ED were age, multiple muscle surgery, binocular surgery. Midazolam premedication, intraoperative dexmedetomidine and fentanyl were associated with lower incidence of ED. On multivariable analysis, younger age (Odds Ratio (OR) = 1.05; p = 0.039), multiple muscle correction (OR = 1.91; p = 0.041), binocular surgery (OR = 1.85; p = 0.021) midazolam premedication (OR = 2.02; p = 0.007), intraoperative fentanyl administration (OR = 1.88; p = 0.031), and intraoperative dexmedetomidine administration (OR = 1.32; p < 0.001), were independent predictors of ED. Conclusion In this study, younger age, multiple muscle surgery, and binocular surgery were the main non-modifiable factors associated with ED in children following strabismus surgery. Administration of midazolam, dexmedetomidine, or fentanyl were associated with lower incidence of ED. Patients at higher risk for ED could be selected for prophylaxis against ED using these medications to prevent ED after strabismus correction surgery in children.

Boergen modification of Harada-ito surgery with and without vertical muscle surgery for acquired unilateral superior oblique muscle palsy.

The purpose is to report the results of the Boergen modification of the Harada-Ito procedure with and without simultaneous vertical muscle surgery in patients with acquired unilateral superior oblique muscle palsy. Files of patients with acquired unilateral superior oblique muscle palsy who were treated with Boergen modification of the Harada-Ito procedure were studied retrospectively. For each patient, age at the time of surgery, the presence of diplopia, compensatory head posture, and ocular deviation before and after surgery were retrieved. Results were evaluated 6 months after surgery. A total of 12 patients with a mean age of 32 years at the time of surgery (range 15-45 years) were included. The underlying etiology was head trauma in eleven patients. The modified Harada-Ito procedure alone was done for three cases (Group 1), and a simultaneous combination of this procedure and vertical muscle surgery was performed in nine patients (Group 2). The average intorsional effect in the primary position was 9.2° (8° in Group 1 and 9.6° in Group 2). The average correction of hypertropia in the primary position was 8.2 prism diopters (PD) (1 PD in Group 1 and 10.6 PD in Group 2). Diplopia in the primary position and downgaze were resolved in eleven patients and ten patients, respectively. Four patients had a compensatory head tilt at their last follow-up. Boergen modification of the Harada-Ito procedure, alone and combined with vertical muscle surgery, successfully corrected primary position diplopia in the majority of the patients.

Evaluation of macular vessel density with OCTA in patients undergoing inferior oblique muscle surgery

Aims: To evaluate pre- and postoperative macular vascular density changes in patients undergoing inferior oblique muscle surgery using optical coherence tomography angiography (OCTA). Methods: 28 eyes of 16 patients who underwent inferior oblique muscle surgery were included in the study. Measurements were taken preoperatively (T0) and one day (PO1), 15 days (PO15) and 6 weeks (PO6w) after surgery. The vessel densities of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris (CCL) were measured by OCTA. Results: This study included 28 eyes of 16 patients. The mean age of the patients was 8.07±5.5 years (4-23 years). SCP and DCP mean vascular densities decreased significantly at PO1 and PO15 compared to T0, but increased at PO6w, reaching their initial levels. Mean CCL levels were lower at PO1 compared to all other measurements and reached their preop values at PO6w. Conclusion: The inferior oblique muscle insertion is known to be close to the macula and surgical interventions for this muscle may cause changes in macular vascular density. In our study, macular vascular density decreased in all parameters at PO1 compared to T0, but almost reached its preop levels at PO6w.

Short-Term Morpho-Functional Changes before and after Strabismus Surgery in Children Using Structural Optical Coherence Tomography: A Pilot Study.

To evaluate the immediate alterations in the thickness of the macular ganglion cell-inner plexiform layer (mGCIPL), peripapillary retinal nerve fiber layer (RNFL), inner retinal layer (IRL), and outer retinal layer (ORL) using spectral domain optical coherence tomography (SD-OCT) subsequent to strabismus surgery in pediatric patients diagnosed with horizontal esotropia. Twenty-eight eyes from twenty-one child patients who had undergone uncomplicated horizontal rectus muscle surgery due to strabismus were included. Measurements of RNFL, mGCL-IPL, IRL, and ORL using structural OCT were conducted both before the surgery and one month after the surgical procedure. Importantly, a control group comprising 14 healthy eyes, matched for age and significant refractive error (<3.00 diopters), was included in the current analysis. Our analysis indicated no significant disparity before and after surgery in terms of best-corrected visual acuity (BCVA), RNFL, IRL, and ORL. Conversely, concerning the macular ganglion cell layer-inner plexiform layer analysis, a substantial increase in mGCL-IPL was observed following the surgical intervention. The mean mGCL-IPL measured 60.8 ± 9.2 μm at baseline and 66.1 ± 13.2 μm one month after the surgery (p = 0.026). Notably, comparison between the strabismus group at baseline and the healthy group revealed a significant reduction in mGCL-IPL in the strabismus group (60.8 ± 9.2) compared to the healthy control group (68.3 ± 7.2; p = 0.014). Following strabismus surgery, our observations pointed towards a thickening of the mGCL-IPL layer, which is likely attributable to transient local inflammation. Additionally, we identified a significant differentiation in the mGCL-IPL complex between the pediatric patient group with strabismus and the control group.

The impact of simultaneous correction of the V pattern on the results of surgical treatment in children with intermittent exotropia.

This study is to investigate the impact of the coexistence of basic intermittent exotropia and vertical incomitance in the form of the V and sub-V pattern on the results of surgical correction of intermittent exotropia. The records of 81 pediatric patients who had surgery for intermittent exotropia and a follow-up of more than 1year were reviewed retrospectively. They were divided into groups: a concomitant group which underwent only horizontal muscle surgery of bilateral lateral rectus recession and a V pattern group which had additional inferior oblique recession, further separated into two subgroups: ≥ 15 prism diopters (classic V pattern group) and ≥ 10 < 15 prism diopters (sub-V pattern group). The surgical outcome, deviation control, stereoacuity, and postoperative drift were assessed after 3months and 1year postoperatively. Patients with sub-V and classic V pattern intermittent exotropia showed significantly better surgical success rate (p = 0.025) and less postoperative drift (p = 0.042) than patients without vertical incomitance. One year after surgery, successful surgical outcome was achieved in 83.72% of the vertically incomitant group: 80.76% for the classic V pattern and 88.24% for the sub-V pattern group, while only in 60.53% of nonpattern patients. Patients operated for intermittent exotropia with a coexistent V pattern have consistently better surgical long-term results than those with only horizontal deviation. Additional inferior oblique recessions in the sub V pattern group provided excellent outcomes with no overcorrections; therefore, surgeons should consider addressing vertical incomitance even when the typical criteria for the V pattern are not met.

Comparison of simultaneous prism and cover test (SPCT) and prism and alternate cover test (PACT) measurements with final power of Press-On prism power dispensed

PurposeTo investigate the association of strabismic angle obtained by simultaneous prism and cover test (SPCT) and prism alternate cover test (PACT) with the final power of Press-On prism used in adults with symptomatic strabismus. Subjects and MethodsThe medical records of consecutive patients seen by a single orthoptist at an urban, tertiary care hospital over a 36-month period were reviewed retrospectively. All subjects had been prescribed Press-on prism for diplopia after evaluation with SPCT and PACT measurements at distance fixation. Prism dispensed was chosen by the patient using a trial Press-On prism set. ResultsA total of 244 charts were reviewed. Of these, 108 adult patients had prism dispensed, and 32 had both SPCT and PACT measurements. Mean SPCT measurement was 7Δ (median, 6Δ; range, 3Δ-14Δ); mean PACT, 13Δ (median, 11Δ; range, 8Δ-20Δ). The mean prism power dispensed was 7Δ (median, 6Δ; range, 1Δ-15Δ); this was not significantly different from mean SPCT (P = 0.35). There was a large difference (6Δ) between mean PACT measurements and mean prism dispensed (P < 0.001). At follow-up of 1 year, 21 patients (66%) remained in prism. Nine patients (4%) elected to undergo eye muscle surgery, 7 with horizontal strabismus, 6 of whom had SPCT measurements of >10Δ and PACT measurements of >15Δ. ConclusionsPress-On prism power used was more closely tied to the angle of strabismus obtained by SPCT. Overall success rate of Press-On prism was good when the prism power dispensed was close to the SPCT measurement, suggesting that it is reasonable to initiate treatment with a weaker prism, approximating the SPCT measurement, building up only if there are continuing symptoms.

Variation between surgeons in rate of reoperation after horizontal strabismus surgery among Medicare beneficiaries: associations with patient and surgeon characteristics and adjustable sutures.

Objective: To quantify variation between surgeons in reoperation rates after horizontal strabismus surgery, and to explore associations of reoperation rate with surgical techniques, patient characteristics, and practice type and volume. Methods: Fee-for-service payments in a national database to providers for Medicare beneficiaries having strabismus surgery on horizontal muscles between 2012 and 2020 were analyzed retrospectively to identify same calendar year reoperations. Multivariable linear regression was used to determine predictors of each surgeon's reoperation rate. Results: The reoperation rate for 1-horizontal muscle surgery varied between 0.0% and 30.8% among 141 surgeons. Just 7.8% of surgeons contributed over half of the reoperation events for 1-horizontal muscle surgery, due to the presence of high-volume surgeons with high reoperation rates. Surgeon seniority, gender, surgery volume, and use of adjustable sutures were not independently associated with surgeon reoperation rate. We explored associations of reoperation with patient characteristics, such as age and poverty. Surgeons in the South tended to have a higher reoperation rate (p=0.03) in a multivariable model. However, the multivariable model could only explain 16.3% of the inter-surgeon variation in reoperation rate for 1-horizontal muscle surgery. Discussion: Strabismus surgery is similar to other areas of medicine, in which large variations in outcomes between surgeons are observed. Future work can be directed towards explaining this variation. Conclusions: Patient-level analyses that fail to consider variation between surgeons will be dominated by a small number of high-reoperation, high-volume surgeons. Order-of-magnitude variations exist in reoperation rates among strabismus surgeons, the cause of which is largely unexplained.

Significant Changes of Corneal Astigmatism After Levator Muscle Surgery for Acquired Blepharoptosis.

To investigate the change of corneal astigmatism after the correction of blepharoptosis. This was a single-center retrospective cohort study conducted in Taiwan from 2017 to 2021. The medical records of patients with acquired blepharoptosis who had received levator muscle surgeries were collected. The differences in corneal astigmatism between the measurements before and at least 1 month after surgeries were investigated. Subgroup analysis of various severities of blepharoptosis and different types of corneal astigmatism was performed to determine their impacts on the axial changes after blepharoptosis surgeries. A total of 120 eyes of 68 patients were enrolled in this study. The mean axial change of corneal astigmatism was 17.4° after blepharoptosis surgeries, and 55 eyes (45.8%) had a change of at least 10°. In the subgroup analysis, the eyes with against-the-rule, with-the-rule, and oblique astigmatism had 42.9%, 68.4%, and 91.7% with an axial change of at least 10° after surgeries, respectively. The averaged axial change of corneal astigmatism after surgeries was 22.7° in eyes with severe blepharoptosis (margin to reflex distance1 < 1 mm), whereas it was 12.0° in eyes with mild-to-moderate blepharoptosis (margin to reflex distance1 ≥ 1 mm). A high proportion of eyes had a crucial axial change in corneal astigmatism after blepharoptosis surgeries, especially in those with oblique astigmatism and severe blepharoptosis. For blepharoptosis patients needing refractive surgeries or astigmatism correction with toric intraocular lens implantation, a surgical correction of blepharoptosis may be considered beforehand.

Effect of Low-dose Atropine on Myopia Control in Children Operated for Intermittent Exotropia

Purpose: To evaluate the effect of low-dose atropine on myopia control in children with a history of surgery for intermittent exotropia (IXT).Methods: We retrospectively reviewed the medical records of children who used 0.05% atropine for ≥ 1 year to control myopia progression. This group included 45 patients with a history of IXT surgery and 57 patients with no such history. The annual changes in spherical equivalent and axial length were compared 6 months before, 6 months after, and 1 year after atropine instillation between the IXT surgery group and myopia controls. In this comparison, the dominant eye was paired with the right eye and the non-dominant eye with the left eye. We also analyzed the difference between IXT surgery cases corrected within versus not within 10 prism diopters (PD) at the start of low-dose atropine treatment.Results: A total of 102 patients had an average of -3.81 ± 1.53 diopters (D) and used low-dose atropine for an average of 16.8 months from a mean age of 8.2 years. On average, the IXT surgery group underwent muscle surgery for 28.1 PD of IXT at 7.8 years. A year after instillation, the myopia progression rate was -0.52 ± 0.89 D/year and 0.27 ± 0.40 mm/year in the IXT surgery group compared to -0.47 ± 0.83 D/year and 0.31 ± 0.24 mm/year in the myopia control group with no significant differences. However, after 6 months of instillation, the dominant eye in the IXT surgery group exhibited a significantly faster myopia progression rate than the right eye in the myopia control group (-0.84 ± 1.61 D/year vs. -0.56 ± 0.80 D/year, &lt;i&gt;p&lt;/i&gt; = 0.04; 0.27 ± 0.33 mm/year vs. 0.22 ± 0.21 mm/year, &lt;i&gt;p&lt;/i&gt; = 0.02). No difference was found in the myopia control effect between corrected and uncorrected cases in the IXT surgery group.Conclusions: The effect of low-dose atropine on myopia control in children after IXT surgery was similar to that in myopia controls. However, it was less effective in the dominant eye during the early treatment period.

Congenital ptosis with aponeurotic maldevelopment: clinical and surgical perspectives

PurposeLevator muscle dystrophy has been commonly accused being the main pathology of congenital ptosis, nevertheless, few reports drew attention to the existence of congenital aponeurotic defects. This study aims at highlighting the detailed clinical and surgical features of aponeurotic maldevelopment together with the efficacy of simple aponeurosis repair.MethodsThis is a retrospective nonrandomised study including patients with congenital ptosis who underwent levator muscle surgery throughout 4 years. Patients’ records were reviewed for the preoperative clinical assessment and photographs, intraoperative recorded data, and videos as well as postoperative data and photographs.ResultsTwenty-seven eyes of 22 patients (9.4%) out of 287 eyes were recorded to have absent levator muscle at its typical anatomical insertion site intraoperatively. The mean preoperative MRD1 was (0.44 ± 1.17 mm). The mean levator function was 8.56 ± 3.89 mm, with higher-than-normal crease position (mean value 10.07 ± 1.62 mm). 25 eyes of included cases (92.6%) showed total absence of the levator aponeurosis edge which only was revealed after cutting through the orbital septal covering of the preaponeurotic fat.ConclusionCongenital aponeurotic defect is an established yet under reported entity of congenital ptosis with reproducible characteristic intraoperative findings. Simple aponeurosis repair could achieve ptosis correction in such cases.

Investigation of alterations in retrobulbar hemodynamics and their correlation with choroidal thickness after strabismus surgery.

To evaluate the changes in retrobulbar circulation after strabismus surgery and to assess the relationship of these changes with choroidal thickness (CT). This prospective study included 26 eyes of 26 patients who underwent strabismus surgery and 15 eyes of 15 healthy individuals as control group. The patients who had single horizontal muscle surgery were included in Group 1 (n = 14); and those who had surgery on both horizontal muscles were included in Group 2 (n = 12). Peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI) and pulsatility index (PI) of ophthalmic artery (OA), posterior ciliary artery (PCA), and central retinal artery (CRA) were measured using Color Doppler Ultrasonography. Subfoveal CT was measured via Optical Coherence Tomography. All measurements were obtained preoperatively, at 1st week and 1st month after surgery. There were no differences regarding preoperative blood flow velocity parameters among the groups. OA RI increased significantly at 1st week and 1st month after surgery in Group 1 and 2 (P = 0.029 and P = 0.045, respectively). There was a significant increase in PCA PSV at 1st week in Group 1 (P = 0.002). There was no difference between the mean preoperative and postoperative CT among the 3 groups. A negative correlation between the percentage changes of CT and CRA EDV was found in Group 2 (P = 0.011). Single and double horizontal rectus muscle surgery have a measurable effect on retrobulbar hemodynamics but these changes do not correlate with CT.