Modified partial Jensen procedure to treat a hypertropic Knobby eye syndrome in a high myopic monocular patient.

We present a case of severe esotropia and hypertropia in a monocular high myope with an inferolateral staphyloma. Surgery was undertaken to secure the inferior rectus to the lateral rectus via a modified partial Jensen technique, along with medial rectus recession successfully improving head and eye positions and ductions.

14†Surgical treatment of heavy eye syndrome by modified loop myopexy.

Heavy eye syndrome or convergent strabismus fixus is an acquired strabismus typically seen in eyes with high myopia. We present a case, discuss the aetiology and management, and include a short video illustrating the surgical procedure undertaken.A 47-year-old highly myopic woman with h/o bilateral cataract surgery and B/L scleral buckling for retinal detachments, had left esotropia and hypotropia measuring more than 40 prism dioptres base-out and 12 prism dioptres base up. MRI orbits showed bilateral asymmetrical medial deviation of ocular bulbs, more on left side. Also, there was degeneration of lateral rectus-superior rectus band with displacement of lateral rectus downwards.She underwent Botox to bi-medial recti after which she could demonstrate potential for binocular single vision. A left un-augmented loop Myopexy procedure and recession of the left medial rectus was thereafter performed under general anaesthesia. After surgery, her eyes were binocularly aligned for near with minimal esotropia for distance.This case suggests that patients with significant esotropia combined with high myopia should be suspected to have heavy eye syndrome. Orbital imaging should be undertaken to demonstrate the anatomical abnormality and muscle paths to confirm a definite diagnosis. Modified Loop Myopexy was found to be effective in this case of heavy eye syndrome.

Long-term results of strabismus surgery for treatment of esotropia in patients with Möbius syndrome.

PURPOSE: To evaluate the surgical results of Möbius syndrome esotropia following bilateral medial rectus recession with and without bilateral Hummelsheim procedure. METHODS: The medical records of patients with Möbius syndrome operated on by a single surgeon from 1993 to 2022 were studied retrospectively. For each patient, age, sex, and ocular deviation before and after surgery were retrieved. Success was defined as a horizontal deviation of up to 15Δ and vertical deviation of <10Δ. RESULTS: Eleven patients were included. Average patient age at the time of surgery was 4 years. Eight patients with esodeviation up to 70Δ underwent bilateral medial rectus recession; 3 patients with esotropia >70Δ underwent recession plus bilateral Hummelsheim procedure. The mean esodeviation before surgery was 52.5Δ in the first group and 86.6Δ in the second group. The mean horizontal deviation at early follow-up was esotropia of 7.4Δ in the first group and of 15Δ in the second group. The early success rate was 87% in the first group and 67% in the second group. Long-term follow-up revealed exoshift in 43% of the patients in the first group and all 3 patients in the second group. CONCLUSIONS: In our small patient cohort of patients with Möbius syndrome, bilateral medial rectus recession corrected esodeviations of up to 70Δ. In more severe cases (>70Δ), adding bilateral Hummelsheim procedure was beneficial.

Epidemiology, clinical features, and surgical outcomes of acute acquired concomitant esotropia associated with myopia.

PURPOSE: To analyze epidemiology, clinical features, and surgical outcomes of type III acute acquired concomitant esotropia (Bielschowsky esotropia (BE)). METHODS: The medical charts of patients diagnosed with acquired concomitant esotropia between 2013 and 2021 were reviewed. Assessed data were age, gender, age at diplopia onset, age at the diagnosis, refraction, visual acuity, neuroimaging, diplopia onset, angle of deviation, stereopsis, surgical procedure, amount of surgery, and relapse of diplopia after surgery. Moreover, we investigated the correlation between the use of electronic devices and the onset of diplopia. RESULTS: One hundred seventeen patients (mean age 35.07 ± 15.81 years) were included in the study. The mean delay to the diagnosis was 3.29 ± 3.62 years. Myopia range was 0 to 17 diopters spherical equivalent. 66,3% spent more than 4 hours a day using laptops, tablets, or smartphones at the onset of diplopia, and 90,6% presented a subacute onset. None showed neurologic signs or symptoms. Patients who underwent surgery were ninety-three, with a rate of surgical success of 93.6%, and a relapse rate of 17.2%. A negative correlation resulted between pre-operative deviation and age at diagnosis (ρ = -0.261; p<0.05), whereas factors associated with surgical failure were older age at diplopia onset (p = 0.042) and longer delay between onset and diagnosis (p = 0.002). CONCLUSION: We registered an outstanding increase in prevalence of BE, which could be related to the exponential increase in the use of electronic devices for professional, educational, and recreational purposes. A prompt diagnosis and an augmented dose of surgery allows good motor and sensory results.

Neurological pathologies in acute acquired comitant esotropia.

BACKGROUND: Acute acquired comitant esotropia (AACE) is an uncommon subtype of esotropia characterized by sudden and usually late onset of a relatively large angle of comitant esotropia with diplopia in older children and adults. METHODS: A literature survey regarding neurological pathologies in AACE was conducted using databases (PubMed, MEDLINE, EMBASE, BioMed Central, the Cochrane Library, and Web of Science) in order to collect data for a narrative review of published reports and available literature. RESULTS: The results of the literature survey were analyzed to provide an overview of the current knowledge of neurological pathologies in AACE. The results revealed that AACE with unclear etiologies can occur in many cases in both children and adults. Functional etiological factors for AACE were found to be due to many reasons, such as functional accommodative spasm, the excessive near work use of mobile phones/smartphones, and other digital screens. In addition, AACE was found to be associated with neurological disorders, such as astrocytoma of the corpus callosum, medulloblastoma, tumors of the brain stem or cerebellum, Arnold-Chiari malformation, cerebellar astrocytoma, Chiari 1 malformation, idiopathic intracranial hypertension, pontine glioma, cerebellar ataxia, thalamic lesions, myasthenia gravis, certain types of seizures, and hydrocephalus. CONCLUSIONS: Previously reported cases of AACE with unknown etiologies have been reported in both children and adults. However, AACE can be associated with neurological disorders that require neuroimaging probes. The author recommends that clinicians should perform comprehensive neurological assessments to rule out neurological pathologies in AACE, especially in the presence of nystagmus or abnormal ocular and neurological indications (e.g., headache, cerebellar imbalance, weakness, nystagmus, papilloedema, clumsiness, and poor motor coordination).

Inferior rectus transposition as a secondary surgery in patients with acquired abducens nerve palsy.

We report the outcomes in 2 patients with acquired abducens nerve palsy with residual esotropia following superior rectus transposition and medial rectus recession who subsequently underwent inferior rectus transposition as a second procedure. Both patients showed improved abduction and reduced esotropia, with no induced cyclotorsion or vertical deviation. Inferior rectus transposition as a secondary procedure in these 2 patients with abducens nerve palsy appeared to augment the effect of prior superior rectus transposition and medial rectus recession.

Risk of consecutive esotropia after surgery for intermittent exotropia according to passive duction force.

PURPOSE: To determine the relationship between consecutive esotropia (ET) and passive duction force (PDF) in patients with intermittent exotropia (XT). METHODS: The study enrolled 70 patients in whom PDF was measured under general anesthesia prior to XT surgery. The preferred eye for fixation (PE) and the nonpreferred eye for fixation (NPE) were determined using a cover-uncover test. The patients were subdivided into two groups according to the angle of deviation at 1 month postoperation: (1) consecutive ET (CET group), >10 prism diopters (PD) of ET; and (2) non-CET (NCET group), ≤10 ET or residual exodeviation. The relative PDF of the medial rectus muscle (MRM) was obtained by subtracting the ipsilateral PDF of the lateral rectus muscle (LRM) from the PDF of the MRM. RESULTS: The PDFs for the LRM in the PE in the CET and NCET groups were 47.28 g and 58.59 g, respectively (p = 0.147), and 56.18 g and 46.59 g for the MRM (p = 0.11), and in the NPE were 59.84 g and 55.25 g, respectively, for the LRM (p = 0.993), and 49.12 g and 50.53 g, respectively, for the MRM (p = 0.81). However, in the PE, the PDF in the MRM was larger in the CET group than in the NCET group (p = 0.045), which was positively associated with the postoperatively overcorrected angle of deviation (p = 0.017). CONCLUSIONS: An increased relative PDF in the MRM in the PE was a risk factor for consecutive ET after XT surgery. Quantitative evaluation of the PDF could be considered when planning strabismus surgery to achieve the desired surgical outcome.

A rare case of intramuscular orbital amyloidosis presenting as progressive esotropia in an adult.

Orbital amyloidosis is an uncommon entity. Lacrimal gland, orbital soft tissue and extraocular muscles are the usual sites of involvement. Deposition of amyloid in the extraocular muscle can be either isolated or associated with systemic amyloidosis. We describe a case of a 43-year-old male with isolated amyloid infiltration of the right lateral rectus muscle presenting as a progressive esotropia. The case was initially misdiagnosed as lateral rectus palsy and myositis due to non-specific radiological features of the entity. The diagnosis was confirmed by a biopsy. Intramuscular Botulinum toxin injection, was administered to the right medial rectus to alleviate diplopia temporarily, and strabismus surgery was planned at a later stage. Amyloid deposition is a rare cause of extraocular muscle enlargement. Histopathology is confirmatory. Screening for systemic amyloidosis is mandatory in all cases.

Four cases of acute comitant esotropia associated with diffuse intrinsic pontine glioma in children.

BACKGROUND: Acute acquired concomitant esotropia (AACE) is usually a benign form of strabismus that infrequently is associated with intracranial pathology. Clinicians have noted an increase in its incidence and theorize that it may be related to public health "lockdown" measures taken in response to the COVID-19 pandemic. With an increased incidence of AACE clinicians must firstly differentiate AACE from common accommodative esotropia and secondly recognize AACE as a possible sign of serious neuropathology.Diffuse Intrinsic Pontine Glioma (DIPG) is a devastating diagnosis for affected families. Children typically present at age 6-7 years with cranial nerve palsies, long tract signs, and/or cerebellar signs. Diagnosis is made from characteristic findings on magnetic resonance brain imaging (MRI brain) and treatment includes radiotherapy and palliative care. Two years from diagnosis, 90% of affected children will have died from their disease. CASE SERIES: We present four cases that attended our pediatric ophthalmology clinic with AACE either as a presenting sign of DIPG or as a clinical finding following a DIPG diagnosis. Patient A (age 5 years) presented to the emergency eye clinic with sudden onset diplopia and intermittent esotropia. Suppression later developed, they had 0.00 logMAR visual acuity either eye, and bilateral physiological hypermetropia. MRI brain imaging requested as a result of the unusual presentation led to the DIPG diagnosis. The other 3 cases (ages 11, 5 & 5 years) were assessed post DIPG diagnosis and found to have an esotropia measuring bigger on 1/3-meter fixation than 6-meter fixation, full ocular motility, physiological hypermetropia or emmetropia, and visual acuity normal for age. Other than patient B (age 11 years), who had papilledema and gaze evoked nystagmus when they were assessed 2 weeks prior to death, no patient had any other clinical eye findings. CONCLUSIONS: This small series of 4 patients attending our clinic within a 12-month period supports the notion that children presenting with AACE should routinely be offered brain MRI. Not all children with DIPG-associated AACE have significant ophthalmic findings indicative of intracranial pathology. With the potential for increased incidence of AACE related to lockdowns, clinicians should be reminded of the infrequent possibility their patient has a more serious condition.

Clinical features, etiological reasons, and treatment results in patients who developed acute acquired nonaccomodative esotropia.

PURPOSE: To evaluate the clinical features, possible etiological reasons, and treatment results in children who developed acute acquired comitant esotropia (AACE) without strabismus in previous years. METHODS: Medical records of the patients who were diagnosed with AACE between July 2017 and June 2021 were retrospectively reviewed. The children with ocular and orbital pathology, hypermetropia > 2.00 diopters, and anisometropia > 1.00 diopters were not included in the study. Possible etiological factors that could cause esotropia, treatment results, motor, and sensory functions were investigated. RESULTS: The mean age at first admission, and the onset of AACE, was 8.8 ± 2.9 (4-13) years of three female (23.1%) and 10 male (76.9%) cases. The causes of AACE were determined to be occlusion of the eye due to corneal foreign body removal in one (7.7%), emotional stress in one case (7.7%), and excessive close work, on computer and smartphone screens in the other 11 cases (84.6%). Orthotropia was achieved in cases who underwent strabismus surgery (n = 10) and in cases using the prism (n = 2); except for one case, all (92.3%) achieved binocular single vision (100 s/arc stereopsis and fusion) after treatment, while there was no binocular single vision in any of the cases before treatment. CONCLUSIONS: Acute acquired comitant esotropia is a rare clinical entity. Successful motor and sensory outcomes can be achieved by strabismus surgery or by prism therapy. It is critical to investigate the patients with AACE in terms of intracranial pathologies, although rarely seen.

Conventional surgery versus botulinum toxin injection for the management of esotropia in children with Down syndrome.

PURPOSE: To compare the success rates of strabismus surgery and botulinum toxin injection (BTX) in treating esotropia in patients with Down syndrome (DS). METHODS: This multicenter retrospective cohort study included all consecutive patients having DS with esotropia between 2014 and 2021 at King Abdullah Specialist Children Hospital, King Abdullah International Medical Research Center, and King Khaled Eye Specialist Hospital, Saudi Arabia. We divided the patients into two groups according to interventions. Success was defined as angle of deviation of <10Δ at final visit. RESULTS: A total of 53 patients were included: 23 in the surgery group and 30 in the BTX group. There were no significant differences between groups with regard to age, sex, diagnosis, spherical equivalent, and preoperative deviation angle. Before the intervention, the median angle of deviation was 30.0Δ (IQR, 30Δ-45Δ) in the surgery group and 37.5Δ (IQR, 28.8Δ-50.0Δ) in the BTX group (P = 0.802). Postoperatively, the median (IQR) deviation angle was 0.0Δ (0.0Δ-16.0Δ) in the surgery group and 22.5Δ (6.75Δ-30.0Δ) in the BTX group (P = 0.006). The success rate in the surgery and BTX groups was 65% and 30%, respectively (P = 0.011). Two patients developed dissociated vertical deviation in the surgery group. One patient presented consecutive exotropia and one inferior oblique overaction in the BTX group. CONCLUSIONS: In this study, conventional surgery showed a higher success rate than BTX in the management of esotropia.

Augmented inferior rectus transposition with medial rectus recession in treatment of chronic unilateral sixth nerve palsy.

BACKGROUND: to report the results of augmented inferior rectus muscle transposition (IRT) in management of chronic sixth nerve palsy. METHODS: a retrospective review of medical records of patients with chronic complete sixth nerve palsy who were treated by augmented full thickness IRT to the lateral border of the paralyzed lateral rectus muscle. Patients were selected for IRT if there was more limitation of abduction in inferior gaze associated with V- pattern esotropia. Medial rectus recession (MRRc) was performed in case of positive intraoperative forced duction. Effect on primary position esotropia, face turn, amount of V-pattern and limitation of ocular ductions were reported and analyzed. RESULTS: the review revealed 11 patients (7 males) with chronic unilateral sixth nerve palsy who were treated by simultaneous augmented IRT and MRRc. Causes of sixth nerve palsy were trauma (6 cases), vascular (3 cases), inflammation and congenital (one case each). Mean age of the patients at the time of surgery was 35.6 years (range; 11-63) and mean follow up was 8.6 months (range; 6-13). Postoperatively, average correction of esotropia, V-pattern, face turn and limited abduction were 35.9 PD, 11.4 PD, 25.9° and 2.2 unit, respectively (p < .00). Postoperative complications in the form anterior segment ischemia, symptomatic induced vertical deviations were not found. CONCLUSIONS: In cases of chronic unilateral sixth nerve palsy associated with more limitation of abduction in downgaze and V-pattern esotropia, augmented IRT could be considered as an effective and safe modality.

A rare cause of acquired esotropia: Leprosy.

Leprosy is an infective chronic granulomatous disease involving the skin and peripheral nerves caused by Mycobacterium leprae. Complications such as lagophthalmos, corneal opacity and uveitis are common, but cranial nerve involvement is rarely seen. The fifth and seventh cranial nerves are most commonly involved. We report a case of acquired esotropia due to sixth nerve palsy following a rare cranial nerve involvement by leprosy.

Advancement of the muscle insertion toward the limbus as an alternative or adjunct to resection.

PURPOSE: To describe the surgical outcomes of patients that underwent strabismus surgery involving advancement of the muscular insertion line toward the limbus. METHODS: The medical records of patients who underwent rectus muscle advancement surgery between January 2009 and June 2019 and had at least 1 year of follow-up were reviewed retrospectively. Patients were classified into one of four types of deviation: (1) convergence insufficiency, without distance deviation; (2) small-angle distance esotropia, with diplopia; (3) residual strabismus after previous surgery; and (4) large-angle exotropia. The first group underwent 2 mm advancement of the medial rectus insertion bilaterally; the second, 2-3 mm advancement of the lateral rectus muscle bilaterally; the third, 2-3 mm advancement of the lateral or medial rectus muscle, with or without simultaneous resection; and the fourth, 3 mm advancement of the medial rectus with simultaneous resection, with or after maximum recession of the lateral rectus, bilaterally or unilaterally. RESULTS: A total of 25 patients were included (mean age, 28.76 ± 22.75 years): 4 with convergence insufficiency, 3 with small-angle distance esotropia and diplopia, 16 with residual strabismus, and 2 with large-angle exotropia. Mean postoperative follow-up was 4.76 ± 2.03 years. Surgery was successful in all patients at 1 year (residual deviation ≤10Δ), and all but 1 at 5 years; 1 patient required reoperation. CONCLUSIONS: Advancement of the muscle insertion proved successful as an alternative or adjunctive procedure to other forms of muscle tightening in the subtypes of patients evaluated in this study.

Surgical outcomes of acquired acute comitant esotropia. Causes and classification.

PURPOSE: To study the results of surgical treatment of acquired concomitant esotropia and its posible causes. METHODS: Retrospective study of the patients with acute acquired esotropia that were operated on since 2017. Distance and near horizontal deviation, spherical equivalent and the excessive use of the tablets and smartphones were analyzed. A good sensorial outcome was considered when stereopsis was recovered and good motor outcome if horizontal deviation was ≤10 prism diopters at the end of the follow-up. RESULTS: A total of 15 cases were included (60% women), mean age: 29.07 years (86.66% ≥16 years). Mean time since the beginning of the symptoms to the surgery was 23.3 months. Mean horizontal preoperative deviation was 19.73 ± 7.2 pd at near and 22.93 ± 7.3 dp at distance decreasing to 3.33 ± 3.8 pd at near and 3.86 ± 3.9 pd at distance (P < .001). The 66.6% had diplopía. The 46.66% had decompensated esophoria or microesotropia, 86,66 % myopia and the 33.33% referred excesive use of the tablets and smartphones. The medial rectus recession were done in 10 cases. A good motor outcome was obtained in the 93.33% of the cases and sensorial outcome in the 53.3% without diplopía. CONCLUSION: Surgery was an excellent treatment to resolve the deviation and diplopia. The esophorias and microesotropias represented near the half of the cases and the excesive use of the tablets and smartphones were the third part of the sample. Most of the patients had myopia.

The Effect of Different Treatment Methods on Acute Acquired Concomitant Esotropia.

Objective: The application of botulinum toxin type A (BTXA) in the treatment of paralytic strabismus has been recognized, but there are few studies on the treatment of acute acquired comitant esotropia (AACE). This study was aimed to investigate the clinical characteristics of AACE and compare the therapeutic effects of BTXA and traditional surgery. Methods: 78 patients with AACE in Renmin Hospital of Wuhan University between March 2019 and March 2021 were reviewed. The relevant medical records of the patients were collected, and they were divided into surgical group (n = 46) and botulinum toxin type A (BTXA) group (n = 32) according to different treatment approaches. The surgical group was treated with squint correction, whereas the BTXA group was treated with microinjection of BTXA in MR. Eye alignment, esotropia, stereopsis, and complications were examined before and after treatment in both groups. Results: The refractive status of 78 patients with AACE was mostly myopic refractive error. In general, the angle of esotropia at distance was larger than which at near, with a statistically significant difference. At follow-up assessments of 1 week, 1 month, 3 months, and 6 months after treatment, the total effective rates of the surgical group and the BTXA group were 100% and 90.48%, respectively. The residual angle of esotropia of both groups was lower after treatment. Additionally, the incidence rate of complications in the BTXA group was significantly lower than that in the surgical group. Conclusion: AACE occurs mostly in people with myopic refractive errors and is associated with prolonged near work. Besides surgical treatment, micro-injection of BTXA is also an effective and safe treatment for AACE.

Clinical profile and management of sixth nerve palsy in pediatric patients (0-15 years) in Southern India - A hospital-based study.

PURPOSE: This study was done to evaluate the clinical profile in pediatric patients (0-16 years) presenting with acute onset esotropia due to sixth nerve palsy and its management options in a tertiary care set up of Southern India. METHODS: A total of 12 patients presenting to our OPD with acute onset esotropia due to sixth nerve palsies were included in this retrospective study. All patients were observed for 6 months and managed with prism and/or patching while waiting for spontaneous resolution and later managed surgically. Neuroimaging was done in all cases. RESULTS: The mean deviation of esotropia at presentation was 30.17 ± 5.7 Prism Diopter (range 12-50 Prism Diopter 95% CI, SD 10.11). Mean age of the patients during presentation was 8.6 ± 2.4 years (range: 1-15 years, SD 4.27). Among the common causes of sixth nerve palsy in our study population were trauma and idiopathic intracranial hypertension followed by tumor and miscellaneous causes. Only three patients underwent surgical correction of residual deviation after a waiting period of 6 months for self-resolution. Spontaneous resolution was observed in 41.6% patients, and surgical correction (unilateral resection-recession) was done in 25% of the patients with good surgical outcome. CONCLUSION: At 1-year follow up, the motor outcome was satisfactory except for one patient who had diffuse pontine glioma and had worsening neurological symptoms on follow-up.

Newly developed abnormal head position and secondary esotropia after strabismus surgery for children with intermittent exotropia.

PURPOSE: To review cases of newly developed AHP and secondary esotropia (ET) after surgical correction for IXT. METHODS: Medical records of cases with newly developed AHP and secondary ET after surgical correction for IXT were retrospectively reviewed. RESULTS: Fifteen cases were included and the mean pre-operative exodeviation was 31.7 ± 10.6 prism diopters (PD) (range: 16-50) at distance. They received bilateral lateral rectus (LR) recessions (13/15), unilateral LR recession and medial rectus (MR) resection (1/15) or bilateral LR recession plus unilateral MR resection (1/15). Fourteen patients developed chin-down AHP with secondary V-pattern ET and 1 presented chin-up AHP with secondary A-pattern ET. The mean esodeviation in primary gaze was 22.7 ± 10.0 PD (range: 3-40) at distance. Twelve cases underwent a second surgery for correction of AHP and secondary ET, and approximately half (5/11) of the recessed LR muscles explored showed a 3-5 mm downward displacement of the new attachment. Surgical management mainly included advancement of LR to the original insertion with a 3-5 mm upward transposition. The AHP dissipated and ocular alignment returned to normal in all of these cases. Three cases did not require further surgery, and their AHP and secondary ET were no longer present at 2-5 months after the first surgery. CONCLUSION: A downward shift of the recessed LR in IXT may lead to secondary V-pattern ET and development of a chin-down AHP. Advancement of LR with an upward transposition serves as an effective procedure for the correction of this complication.

Strabismus Repair in Children with Varying Severity of Cerebral Palsy.

OBJECTIVE: To study the success rate of strabismus surgery in patients with varying levels of severity of cerebral palsy (CP). DESIGN: A retrospective study was conducted. PARTICIPANTS: Sixty-four patients with varying severity of CP were included. METHODS: All patients with different CP severity levels underwent strabismus surgery. Success was defined as any postoperative heterotropia outcome of less than 10 prism diopters in primary position. Statistical analysis was conducted using chi-square. RESULTS: The mean age at the time of strabismus surgery was 3.1 years, and the mean follow-up was 6.0 years. The most common types of strabismus were infantile-onset exotropia in 36 patients (56%) and infantile-onset esotropia in 28 patients (44%). Surgical success was found to be better in patients with mild GMFCS (GMFCS levels 1-2) with 68% having less than 10 PD of eso or exotropia in primary gaze, as compared to patients with severe GMFCS (GMFCS levels 3-5) (38% with 10 PD of heterotropia) (P < .05; χ2). Refractive errors included myopia (27.5% in mild cases and 41.6% in severe), emmetropia (10% in mild and 8.3% in severe) and hyperopia (62.5% in mild and 50% in severe). Around 50% of the mild cases had absent binocular fusion compared to 66.6% of those with severe CP. Amblyopia was found in 62.5% of the mild cases and 54.1% of the severe cases. Nystagmus was present in 25% with mild disease and 29.1% of those with severe disease. CONCLUSION: Restoration of good ocular alignment in patients with CP is achievable in more than half of the cases. Patients with more severe CP have poorer outcomes than those with milder palsies. There appears to be no difference in outcomes between the different types of strabismus.

Medial rectus disinsertion for management of chronic complete sixth nerve palsy.

PURPOSE: To report the outcomes of the medial rectus (MR) disinsertion procedure for the management of refractory esotropia (ET) with or without Abnormal head posture (AHP) in chronic complete sixth nerve palsy. METHODS: This is a retrospective case series of patients with sixth nerve palsy who suffered from residual ET and diplopia following the conventional strabismus surgeries and underwent MR disinsertion procedure between April 2017 and February 2020. This procedure was offered to the patients who declined to use prism and did not wish to perform surgery on the fellow eye. The demographic and clinical data, including sex, age, visual acuity, pre and postoperative angle of strabismus, duction limitations, results of forced duction and force generation tests, details of prior strabismus surgeries, orbital CT scan findings, and follow up duration were collected from the medical records. RESULTS: Six patients were enrolled in this study. Mean age was 35.0 ± 14.0 years, and mean follow-up was 15.3 ± 5.9 months. The ET at the Primary position (PP) was 35.0 ± 18.4 prism dioptre (PD) before MR disinsertion, which decreased to 14.2 ± 17.4 PD after MR disinsertion procedure. Four cases needed additional complementary surgeries to improve residual ET in PP. No case developed overcorrection. Abduction deficiency was -5.0 ± 1.3 before MR disinsertion, which improved to - 2.8 ± 0.5 units at last follow-up. The mean of induced adduction deficiency was - 2.9 ± 0.4 at last follow-up. CONCLUSIONS: MR disinsertion can be considered in patients with chronic complete sixth nerve palsy and refractory diplopia when the conventional methods have failed.