Back To Search Results

Brown Syndrome

Editor: Jahanzeb Malik Updated: 3/3/2024 6:09:45 PM

Introduction

Brown syndrome can be acquired or congenital and is caused by damage to the trochlea of the superior oblique muscle tendon, an abnormality of the superior oblique tendon itself, abnormalities of the tissue around the rectus extraocular muscles, the rectus pulleys, or a congenital abnormality of the superior oblique muscle itself that results in a restriction present at birth.[1][2] This tethering effect may cause difficulties with elevation noted early in childhood as the child attempts to fixate on objects in their superior visual field. 

Acquired Brown syndrome, on the other hand, may develop secondary to inflammatory processes, trauma, surgery, or systemic conditions such as rheumatoid arthritis. It can vary in presentation and severity, often presenting diagnostic and therapeutic challenges. A pseudo-Brown syndrome is sometimes seen following implant surgery is not due to superior oblique muscle-tendon pathology.[3]

For this review, true Brown syndrome is due to a congenital cause, with a constant limitation of elevation and a positive traction test secondary to a tight, superior oblique tendon. The pathophysiology behind Brown syndrome centers on the inability of the superior oblique tendon to move freely through the trochlea, a fibrocartilaginous loop that acts as a pulley. The tendon may be inelastic or have an abnormal course in the congenital variant.[4]

Clinically, Brown syndrome is characterized by a triad of features: limited elevation in adduction, widening of the palpebral fissure in attempted upgaze, and a strange head posture adopted by the patient to minimize diplopia and maximize binocular vision. These clinical signs, often associated with a click or snap felt on attempted elevation in adduction, can be pathognomonic.[5]

The diagnosis of Brown syndrome is primarily clinical, based on a comprehensive history and detailed ocular examination, including forced duction testing and the assessment of ocular motility. Diagnosis is often challenging; a thorough history and clinical examination are necessary to determine etiology and management. Imaging techniques such as magnetic resonance imaging (MRI) or computed tomography (CT) may be employed to elucidate the anatomical details in complex cases or when planning for surgical intervention.[6] 

Management strategies for Brown syndrome vary from conservative observation to surgical correction, depending on the severity of the condition and its impact on the patient's visual function and quality of life. Non-surgical approaches may include prisms for mild cases or therapeutic exercises. However, in cases where significant abnormal head posture, diplopia, or cosmetic concerns are present, surgical intervention might be considered. Surgical options typically aim to lengthen or alter the course of the superior oblique tendon to alleviate the restriction.

Brown syndrome poses unique challenges regarding its impact on the visual axis and patients' psychosocial well-being. The condition can be isolating and functionally limiting, particularly in cases where compensatory head postures are significant.[5] This review seeks to explore the intricacies of Brown syndrome, discussing its etiology, clinical features, diagnostic approaches, and management options, emphasizing the latest advancements in treatment and patient care.

In 1949, Dr. Harold Brown first described 8 cases of a new ocular motility condition, which presented with restricted elevation in adduction, among other features.[7][8] The clinical features were similar to those of an inferior oblique palsy, except that superior oblique muscle overaction was minimal. During surgery, Brown discovered a shortened tendon sheath of the superior oblique muscle tendon, which was thought to restrict passive elevation movement in the adducted field. Hence, the initial name "superior oblique tendon sheath syndrome" was used. After extensive further investigation, it was demonstrated that key clinical features were a V or Y pattern strabismus, divergence in upgaze, downdrift in adduction, and a positive forced duction test (also known as a traction test) for ocular elevation in the nasal field.[7] The condition, Brown syndrome, has since been recognized as a significant cause of vertical strabismus, with implications for both binocular vision and quality of life. 

Etiology

Register For Free And Read The Full Article
Get the answers you need instantly with the StatPearls Clinical Decision Support tool. StatPearls spent the last decade developing the largest and most updated Point-of Care resource ever developed. Earn CME/CE by searching and reading articles.
  • Dropdown arrow Search engine and full access to all medical articles
  • Dropdown arrow 10 free questions in your specialty
  • Dropdown arrow Free CME/CE Activities
  • Dropdown arrow Free daily question in your email
  • Dropdown arrow Save favorite articles to your dashboard
  • Dropdown arrow Emails offering discounts

Learn more about a Subscription to StatPearls Point-of-Care

Etiology

The consensus is that the superior oblique tendon-trochlear complex dysfunction results in Brown syndrome. The condition is commonly divided into primary congenital and acquired causes. Acquired cases can be further classified into inflammatory, traumatic, or iatrogenic, although many different causes have been identified and are listed below for completeness.[7][5]

Congenital Brown Syndrome

  • The tight, superior oblique anterior tendon sheath
  • Short superior oblique muscle and tendon
  • Nodule on the superior tendon
  • Anomalous innervation
  • Tight or misaligned pulley system
  • Congenital fibrosis of the tendon [9]

Acquired Brown Syndrome

  • Systemic disease
  • Dysthyroid disease
  • Enteropathic arthropathy
  • Hurler-Scheie syndrome
  • Hypogammaglobulinemia
  • Juvenile rheumatoid arthritis
  • Rheumatoid arthritis
  • Sinusitis
  • Sjogren syndrome
  • Systemic lupus erythematosus
  • Iatrogenic [10]

Ophthalmic Etiology

  • Blepharoplasty
  • Glaucoma implant in the superior nasal quadrant
  • Orbital floor fracture
  • Retinal encircling band
  • Sinus surgery/sinusitis
  • Superior oblique tuck
  • Trochleitis
  • Neoplasms of superior nasal orbit
  • Trauma to the superior or nasal orbit, eg, canine tooth syndrome [11]

Other Causes

  • Cyclic Brown syndrome
  • Idiopathic
  • Inflammatory click syndrome
  • Tenosynovitis of the superior oblique
  • Cardiopulmonary resuscitation
  • Postpartum
  • Infection
  • Age-related degeneration

Epidemiology

Raynor and Hiatt, in the 1970s, estimated Brown syndrome to occur in 1 in 450 strabismus cases.[7] The incidence increases when considering vertical muscle abnormalities. Urist et al. found 23 patients with Brown syndrome from 226 patients with vertical muscle paresis, all with positive traction tests (also known as forced duction test).[12] 

Numerous studies have found that Brown syndrome is more common in females, with 10% demonstrating bilaterality.[8][13] Brown syndrome has also been associated with Duane syndrome, crocodile tear syndrome (gustatory lacrimation), congenital ptosis, and Marcus Gunn syndrome.[14][15]

Pathophysiology

The pathophysiology of Brown syndrome is predominantly mechanical, involving dysfunction of the superior oblique tendon-trochlear complex, which impairs the normal movement of the eye, specifically the ability to elevate the eye in the adducted position. The superior oblique tendon has a transparent and avascular capsule, similar to the capsule that envelops the tendons of the other extraocular muscles. Parks discovered the tendon and Tenon capsule have a sleeve arrangement, which permits movement of the superior oblique through the trochlea in a telescoping manner.[5] The superior oblique muscle plays a pivotal role in eye movement, particularly in depression, abduction, and intorsion of the eyeball. This muscle passes through a fibrocartilaginous loop known as the trochlea before inserting into the top-back part of the eyeball. The tendon must be able to slide through the trochlea smoothly to allow a full range of motion.[4]

The majority of primary congenital (and a significant proportion of acquired) cases of Brown syndrome are due to anomalies in the superior oblique tendon, trochlear apparatus, or both. Helveston et al described 4 components of the trochlea: a cartilaginous "saddle," an intracochlear portion of the superior oblique tendon, a fibrovascular sheath around the tendon, and a dense fibrous section that secures the trochlear saddle to the medial wall of the orbit. A bursa-like structure between the tendon's vascular sheath and the trochlear saddle was also revealed, and any excess fluid accumulation or deposition in this space would limit movement through the trochlear tunnel. Helveston et al. hypothesized that this was the cause of the "click" in acquired Brown syndrome.[16] Modern high-resolution orbital imaging studies have investigated the size and contractility changes in the superior oblique muscle, which is hypothesized to be the origin of the abnormal mechanical loading found in Brown syndrome.[17] Evidence now suggests that much of the coordination of extraocular muscle innervations is determined by orbital biomechanics, although there is also extensive debate regarding the correct theory governing muscle movement.[18][19][20][21]

In congenital cases of Brown syndrome, the tendon may be too short, inelastic, or have an abnormal course. Additionally, the trochlea may be malformed. These anomalies could be a result of developmental errors during gestation.[22] In cases of acquired Brown syndrome, inflammation, scarring, or surgical changes around the trochlea can lead to a secondary restriction of the tendon. Trauma or systemic diseases such as rheumatoid arthritis can cause inflammation and subsequent fibrosis around the trochlear region, leading to similar mechanical restrictions.[23] 

The mechanical limitation on the tendon's movement results in a characteristic inability to elevate the eye when it is turned toward the nose (adducted). This can lead to the following:[24]

  • Abnormal Head Posture: Patients often adopt a head tilt toward the opposite shoulder of the affected eye to maintain binocular vision and avoid diplopia (double vision).[25]
  • Limited Elevation: The eye may show a limitation of elevation in adduction, which is the hallmark of Brown syndrome. This limitation is often more pronounced in upgaze while the eye is adducted.[26]
  • Diplopia: Some patients may experience double vision due to the misalignment of the eyes, particularly when looking upwards.[27]

In an attempt to compensate and adapt to the restriction in eye movement, the brain may increase innervation to the inferior oblique muscle, which antagonizes the superior oblique muscle. Over time, some patients can develop secondary changes in the affected eye's movement patterns to minimize the impact on vision. Understanding the underpinnings of this condition is crucial for proper diagnosis and treatment, whether surgical intervention to release the restriction or other therapeutic modalities to manage the symptoms.[28]

Histopathology

The histopathology of Brown syndrome relates to the microscopic anatomical changes in the tissues of the superior oblique tendon and the trochlea. An in-depth examination of these tissues can reveal the structural abnormalities that contribute to the clinical features of the condition. However, direct histopathological examination in Brown syndrome is not commonly reported, as it would typically require surgical biopsy or post-mortem analysis, which are not standard procedures for this condition. Nevertheless, insights have been gained from the few studies that have examined excised tissue from patients undergoing surgical treatment for Brown syndrome, as well as from animal models.[29] The findings from available studies contribute to understanding its etiology, particularly the differences between congenital and acquired forms. These insights help to guide the development of surgical techniques for the condition and improve the overall understanding of its pathogenesis.[5]

Histopathological findings found in congenital Brown syndrome may include the following:

  • Tendon Abnormalities: The superior oblique tendon may be congenitally short, tight, or inelastic. Histologically, this could manifest as an increased density of collagen fibers, decreased spacing between fibers, or abnormalities in the composition of the extracellular matrix.[30]
  • Trochlear Dysplasia: The trochlea, which functions as a pulley for the tendon, may be abnormally formed, with histological findings potentially showing malformed cartilage, fibrosis, or aberrant connective tissue architecture.[31]
  • Tenosynovial Changes: The sheath surrounding the tendon may be thickened or show fibrotic changes. This could be observed as an increase in connective tissue or a disorganized arrangement of tenosynovial cells.[32]
  • Acquired Brown syndrome's histopathological findings are often related to the underlying cause, such as the following:[29]
  • Inflammatory Infiltrates: If the syndrome is due to inflammatory processes, biopsy may reveal inflammatory cell infiltrates, such as lymphocytes or plasma cells, within the tendon or trochlear tissues.[33]
  • Fibrosis: Following inflammation or trauma, fibrotic tissue can replace the normal architecture of the tendon or trochlea. This would be seen as an excess of collagen deposition and fibroblast proliferation.[34]
  • Granulomatous Reaction: In cases related to granulomatous diseases, such as sarcoidosis, histology may show granulomas—collections of macrophages often surrounded by a rim of lymphocytes.[35]

Histopathological examination in Brown syndrome is challenging due to the rarity of tissue samples. Most patients are managed with conservative treatments or surgeries that do not involve excision of affected tissues. Therefore, most information on the histopathology of Brown syndrome comes from indirect evidence or extrapolation from similar conditions affecting tendons and sheaths.

History and Physical

The history and certain physical findings depend on the etiology of Brown syndrome and will determine the evaluation and management strategies. The reported clinical features associated with Brown syndrome have not changed significantly since the initial studies.[8] The hallmark sign is a limited elevation in adduction. Von Noorden described in detail variable features which are not always present.[8][5] A positive, forced duction test confirms the diagnosis. A hypotropia can sometimes be present in the primary position, often proportional to the restriction severity. An abnormal head posture consisting of a chin up and a contralateral face turn to avoid hypotropia allows for binocular fusion and comfortable vision. Patients who have acquired Brown syndrome, especially in adulthood, will be more likely to experience diplopia when tropic.

Systemic features can also be present in acquired Brown syndrome of inflammatory etiology, ie, supranasal orbital pain and tenderness on movement or palpation.[36][37][38] Some patients may experience a tactile or auditory click when the affected eye moves through the area of restriction. This is due to the tendon catching and then releasing as it moves through the trochlea.[39] 

Clinical Exam Features

  • Deficient or absent elevation in adduction
  • Normal or minimal elevation deficiency in the abduction
  • Mild elevation deficit in the primary position
  • Positive forced duction test
  • Minimal or no superior oblique overaction [40]

Variable Features

  • V-pattern strabismus due to divergence in up-gaze
  • Widening of the palpebral fissure in adduction
  • Abnormal head posture (chin up and contralateral face turn)
  • Hypotropia in the primary position [41]
  • Double vision may occur due to the misalignment of the eyes when looking upwards or in other directions that stress the affected tendon.[27]
  • In primary and downward gazes, eye movements are usually normal or near-normal. The restriction is primarily evident in upward gaze in adduction.[42]
  • In some congenital cases, especially if the condition is unilateral and not addressed early, amblyopia (lazy eye) can develop in the affected eye due to the misalignment of the eyes and the consequent lack of use.[43]
  • Down-shoot in adduction when returning to primary gaze following attempted upgaze in adduction.[44]
  • Asymptomatic presentation in mild cases, with discovery during a routine eye examination.[45]

The clinical presentation of Brown syndrome can vary from mild to severe, and the impact on vision can range from inconsequential to significantly disabling, depending on the degree of restriction and the presence of binocular vision. Diagnosis is often made clinically through observation and specific tests of ocular motility. Imaging studies, such as MRI or CT scans, can be helpful in complex cases to visualize the anatomy of the superior oblique tendon and trochlea. Treatment depends on the severity of the symptoms and may range from observation for mild cases to surgical intervention for more significant limitations.[46]

Evaluation

Evaluating Brown syndrome involves a comprehensive approach that includes a thorough clinical history, detailed ophthalmologic examination, and, in some cases, specialized imaging. The goal is to confirm the diagnosis, assess the extent of the condition, and plan appropriate management. It may not always be easy for a general ophthalmologist to diagnose Brown syndrome in a child. An excellent and meticulous evaluation of ocular motility is required, and basic knowledge of pediatric ophthalmology is essential in these cases. These cases must be referred to a pediatric ophthalmologist for diagnosis, evaluation, and timely management.[9]

Following a detailed history, the clinical evaluation should include a thorough examination of ocular motility. Clinical features of Brown syndrome will be sought, and a forced duction test will be conducted. This can be performed with a local topical anesthetic (the patient may experience discomfort), or it can be achieved with the patient under anesthesia in the operating room. A positive test is demonstrated by restriction of passive elevation in adduction of the affected eye.[9] Retroplacement of the globe with forceps during attempted passive elevation in adduction will stretch the superior oblique muscle, accentuating the restriction of Brown syndrome. Depending on the etiology, further imaging or laboratory investigations may become necessary, such as radiologic imaging in cases of traumatic Brown syndrome and referral to others in the medical team for managing inflammatory causes may be warranted.[5]

An outline of the clinical history evaluation process is as follows:

  • Onset and Duration: Determine whether the condition is congenital (present at birth) or acquired (developed later in life).
  • Symptoms: Document symptoms such as difficulty moving the eye, double vision (diplopia), or abnormal head postures.[27]
  • Associated Conditions: Inquire about previous eye surgeries, trauma, or systemic diseases like rheumatoid arthritis, which could lead to acquired Brown syndrome.[30]
  • Ophthalmologic Examination
  • Visual Acuity Test: Assess the visual acuity in each eye to check for any vision impairment.
  • Binocular Function Tests: Evaluate for binocular vision and the presence of diplopia.[47]
  • Ocular Motility Assessment: Observe the range of motion of the eyes, especially looking for limitation of elevation in adduction—the hallmark of Brown syndrome.[9]
  • Forced Duction Test: Performed to determine if the restriction is mechanical. The eye is gently moved to test if there is a physical restriction to movement.[48]
  • Slit Lamp Examination: To assess the health of the anterior segment of the eye.[49]
  • Fundus Examination: Evaluate the health of the posterior segment of the eye, especially if other ocular pathologies are suspected.[50]
  • Special Tests
  • Synoptophore Examination: This can be used to assess binocular vision and the presence of any compensatory head postures.[51]
  • V-Pattern Evaluation: Check for V-pattern strabismus, common in Brown syndrome.[52]
  • Imaging Studies
  • Orbital Imaging (MRI or CT Scan): These may be indicated in complex cases to visualize the anatomy of the superior oblique tendon and trochlea, especially in acquired Brown syndrome or when surgical intervention is considered.[29]

*Reference to the clinical history evaluation process [9]

Treatment / Management

Observation and conservative management are the mainstay for most forms of Brown syndrome. Spontaneous improvement is common in acquired cases, although less common in congenital ones. The treatment goals are the improvement of binocular fusion in physiological fields of gaze and the normalization of vision. Non-surgical treatment includes prism glasses for patients with diplopia, orthoptic eye exercises, and treatment of underlying causes, eg, an oral course or local injection of corticosteroids for inflammation. Improvements after daily eye exercises have been reported in case series and reports. In cases of acquired Brown syndrome, treating the underlying cause, such as resolving sinusitis or managing rheumatologic conditions, is crucial. Both oral administration and injection of corticosteroids have been effective in cases of acquired Brown syndrome due to juvenile idiopathic arthritis. Steroid-sparing immunosuppressants, such as adalimumab, have been used successfully in isolated cases of Brown syndrome refractory to steroids or nonsteroidal anti-inflammatory drug therapy.[53] (B3)

Surgical treatment is indicated if there is hypotropia or symptomatic anomalous head posture in the primary position or both. If the patient finds the cosmetic appearance unacceptable, that may be a relative indication for surgery. Tenotomy of the superior oblique tendon has proved more effective than removing the tendon sheath. Severing the entire tendon can lead to unpredictable results, including causing superior oblique palsy.[13] Parks and Eustis have proposed an ipsilateral inferior oblique recession with the tenotomy to reduce the effect of secondary superior oblique palsy.[54] Wright described the insertion of a silicone expander for controlled and effective elongation of the superior oblique tendon in 1991; it is still used today.[55][56] Adjustable sutures may be used to fine-tune the tendon length during surgery. Medical grade silicone, eg, retinal band, is inserted between cut ends of the superior oblique tendon and sutured in place without disruption of the floor of the tendon capsule. Another method of weakening the superior oblique is via a graduated recession, first proposed by Calderia in 1975 in treating A-pattern strabismus with superior oblique overaction.[57] Moghadam et al. reported effective treatment of severe congenital Brown syndrome with a superior oblique tendon split lengthening technique.[58] Trochlea reconstruction and adhesiotomy have been used for cases of acquired Brown syndrome, where this is the source of elevation limitation.[59] Orthoptic exercises are prescribed postoperatively.(B2)

Differential Diagnosis

Proper diagnosis is essential for effective management. The following are some critical and common differential diagnoses that need to be considered while establishing the diagnosis of Brown syndrome:

  • Inferior oblique palsy, paralysis or paresis of the inferior oblique muscle, is rare. 
  • Orbital fractures can cause extraocular muscle entrapment and mechanical limitation of elevation. This can be differentiated from Brown by marked restriction of elevation in both abduction and adduction and associated findings such as a history of trauma, infraorbital paraesthesia, or enophthalmos.[60]
  • Superior oblique overaction (with or without inferior oblique palsy) reveals free passive elevation with forced duction testing and an "A" pattern on upgaze due to superior oblique overaction, in contrast to Brown syndrome. 
  • Congenital fibrosis syndromes can affect multiple extraocular muscles. The elevator muscle can also be affected, resulting in ptosis, which, along with elevation deficiencies both in abduction and adduction, helps to differentiate from Brown syndrome.
  • Double elevator palsy (monocular elevation deficiency) occurs when the elevation deficiency in abduction is equal to or greater than in adduction. Forced duction testing can be positive and is accentuated by the proptosis of the globe.[61]
  • Adherence syndromes [5]
  • Congenital cranial dysinnervation disorders (CCDDs) are characterized by abnormal development of cranial nerves and the muscles they innervate. One example is Duane Retraction Syndrome, which can present with restricted eye movement.[62]
  • Myasthenia gravis is an autoimmune condition that can cause variable weakness of the extraocular muscles, leading to symptoms that could be mistaken for Brown syndrome. However, the variability and fatigability of symptoms are key distinguishing features.[63]
  • Strabismus fixus is a severe form of strabismus with a marked limitation of movement in one or more directions, potentially resembling Brown syndrome.[64]
  • Iatrogenic causes (post-surgical changes), especially after strabismus surgery or surgeries involving the orbit, can sometimes lead to restricted ocular motility, similar to Brown syndrome.[65]
  • Orbital tumors or inflammation in the orbit can restrict eye movement due to mechanical obstruction or muscle involvement.[66]
  • Stiff Eye Syndrome is a rare condition characterized by a generalized restriction in eye movements due to fibrosis of extraocular muscles.[67] 

In the diagnostic process, a detailed clinical history, comprehensive ocular examination, and, in some cases, imaging studies are essential to differentiate Brown syndrome from these conditions. The specific features of eye movement limitation, the presence or absence of pain, systemic signs and symptoms, and the response to diagnostic tests like the forced duction test can help arrive at the correct diagnosis. Collaboration with neurologists, rheumatologists, or other specialists may also be required in complex cases.

Treatment Planning

The treatment for Brown syndrome varies based on its etiology and the severity of the symptoms. Children may outgrow congenital Brown syndrome without treatment, but they should have regular eye exams to monitor changes. In cases of Brown syndrome, which can be caused by an inflammatory condition, autoimmune diseases, infections, or trauma, the inflammation is treated to alleviate the symptoms. Common medications used to treat include NSAIDs, corticosteroids (oral or possibly injected directly into the superior oblique), and immunosuppressants. Surgery is not commonly required, but for severe cases that don't respond to other treatments, surgical options such as tenotomy, tenectomy, or cyst removal may be considered.[9]

Staging

The severity of Brown syndrome can be graded as follows:

  • Mild: Restricted elevation in adduction, no hypotropia or down shoot in adduction.
  • Moderate: Restricted elevation and downshoot in adduction, no hypotropia in the primary position.
  • Severe: Restricted elevation and marked down shoot in adduction with hypotropia present in primary position.

Prognosis

Many primary congenital Brown syndrome cases result in spontaneous improvement with no intervention other than simple observation. Furthermore, there is less need for upgaze as the child grows unless the final height is below average.

The prognosis for acquired Brown syndrome is generally favorable. Symptoms often improve with appropriate treatment of the underlying cause. Some children born with Brown syndrome may outgrow it without any specific treatment as they mature. Even in cases where surgery is needed, Brown syndrome typically does not have long-term adverse effects on vision or eye health. Effective management through conservative measures or surgical intervention can improve eye alignment and symptom relief. The vast majority of children with Brown syndrome develop good vision in both eyes and good depth perception (stereopsis). Surgical treatment is reserved for cases with significant misalignment of the eyes or severely restricted upward movement of the eye, aiming to weaken the superior oblique muscle to improve eye function.[9] Surgery is unpredictable, with subsequent procedures often necessary to treat an iatrogenic superior oblique palsy caused by tenectomy or tenotomy.

Inflammatory causes of Brown syndrome are characterized by the ocular motility findings of pain, which can be localized to the affected trochlear region. Local tenderness on palpation is often present and can fluctuate with relapsing episodes. Peri-ocular corticosteroid injections to the affected area have been described with a good response.[68] 

Post-traumatic Brown syndrome has become less frequent in countries that have stricter road safety regulations. Surgical treatment, such as superior oblique tenotomy, often requires a second procedure on the ipsilateral and contralateral vertical recti and oblique muscles to improve the field of binocular vision.[69]

Complications

Intraoperative complications associated with surgical interventions include excessive bleeding, lost muscle, perforation of the globe, and damage to surrounding ocular structures. Postoperative complications are scarring, under and over-correction, superior oblique palsy, need for further surgery, and implant extrusion (in cases of a silicone tendon expander).[70]

Postoperative and Rehabilitation Care

Postoperative and rehabilitation care for patients with Brown syndrome are crucial components of treatment, especially if invasive surgery has been performed. Here is an outline for managing care after an operative procedure:

Postoperative Care

  • Pain management: Provide appropriate pain relief measures, as eye surgery can cause discomfort. This may include medications and advising the patient on methods to rest the eye.
  • Infection prevention: Educate the patient on signs of infection and provide antibiotic eye drops if necessary to prevent postoperative infections.
  • Eye protection: Advice on protecting the eye from injury and avoiding activities that may strain the eye during healing.
  • Follow-up appointments: Schedule regular follow-up appointments to monitor the healing process and ensure the eye is recovering as expected.
  • Assessing for complications: Be vigilant for complications such as strabismus or double vision, which may require further treatment.[70]

Rehabilitation Care

  • Visual therapy: If recommended, begin visual therapy with an orthoptist or a similar specialist to improve eye coordination and function.
  • Exercises: Prescribe specific eye exercises to help strengthen the muscles and improve eye movement post-surgery.
  • Monitoring visual acuity: Regularly check the patient's visual acuity to ensure no loss of vision or development of amblyopia, especially in children.
  • Adjusting daily activities: Advice on modifications to daily activities to accommodate any temporary visual limitations.
  • Support and counseling: Offer psychological support and counseling, as coping with visual impairment can be challenging for the patient and their family.[70]

Coordination with Rehabilitation Specialists

  • Referral to specialists: Refer the patient to an eye movement specialist or occupational therapist if there are difficulties with daily activities due to altered vision.
  • Collaborative care plan: Develop a care plan in collaboration with the rehabilitation team to address the patient's specific needs.
  • Patient education: Provide education on the importance of adhering to the rehabilitation protocol to ensure the best outcome.
  • Adaptive devices: In some cases, adaptive devices may be needed to assist with reading or other activities requiring acceptable visual acuity.

Long-Term Management

  • Lifestyle adjustments: Patients may need to make long-term adjustments if there are permanent limitations in eye movement.
  • Regular eye examinations: Stress the importance of ongoing eye examinations to monitor for any changes or long-term effects of the surgery.
  • Community resources: Connect the patient with community resources and support groups for individuals with visual impairments.[70]

A successful recovery from surgery for Brown syndrome requires a comprehensive approach that combines medical management with rehabilitative strategies. A multi-disciplinary team that includes surgeons, primary care physicians, nurses, therapists, and counselors can provide a supportive network to address all aspects of the patient's health and well-being.

Deterrence and Patient Education

Educating the patient and family about the nature of the condition, treatment options, and the importance of follow-up is vital. In children, parents should be informed about the potential for spontaneous improvement and the need for regular monitoring.[71] Conservative management is adequate if patients are unconcerned by their compensatory head position and do not have diplopia.

Treating the underlying cause of acquired Brown syndrome can lead to symptom relief. If surgery is indicated, a detailed discussion with the patient regarding risks and benefits, including possible worsening of symptoms, is necessary before proceeding. Patients can also be provided with relevant educational material and directed to support groups, which can benefit their well-being and outcomes.[9]

Deterrence and patient education are critical components of managing Brown syndrome.

Deterrence

  • Regular eye examinations are essential to monitor their condition and catch any changes early.
  • Avoiding trauma that could lead to head or eye injuries can avoid exacerbating the condition.
  • Managing Inflammation through medication or other medical advice can help decrease complications.[72]

Patient Education

  • Understanding the condition by educating patients on what Brown syndrome is, how it affects the eyes, and the potential causes helps holistic care.
  • Treatment options should be explained, including observation, physical therapy, and possible surgical interventions.
  • Symptom recognition of symptoms that may indicate worsening of the condition, such as increased difficulty with eye movements or pain, should prompt patients to seek medical attention.[73]
  • Self-care techniques, such as exercises that can be done at home to maintain eye mobility and comfort, can improve quality of life.[74]
  • The impact on lifestyle should be discussed, and strategies should be offered to cope with these challenges, such as adopting specific head postures to aid vision.
  • Support services information, including counseling or therapy if needed to cope with the emotional and psychological aspects of living with a chronic condition, should be offered.[75]
  • Family education about the potential for inheritance and the importance of genetic counseling should also be offered.
  • Visual aids to help patients and their families understand the anatomy of the eye and how Brown syndrome affects it can help demystify the condition and empower patients with knowledge.

In providing education and deterrence strategies, it is essential to tailor the information to the age and understanding level of the patient. For children, using simple language and engaging materials can help make the information more accessible. For adults, detailed explanations and written materials may be more appropriate. Regular follow-up appointments are also essential for assessing the patient's understanding and adherence to management strategies.[11]

Pearls and Other Issues

Brown syndrome can be challenging to diagnose, with multiple etiologies possible in the acquired category. A thorough history and clinical evaluation are, therefore, essential. Observation and conservative management in primary congenital Brown syndrome can allow most patients time for spontaneous improvement to occur. Surgery can be reserved for patients who show no improvement; however, multiple surgeries are often required. Inflammatory causes of Brown syndrome could respond to local corticosteroid injection. Traumatic Brown syndrome is challenging to manage, often with disappointing results.[5]

Key thoughts to keep in mind regarding Brown syndrome: 

  • Early detection: Emphasize the importance of early detection and intervention, especially in children, to prevent long-term complications such as amblyopia.
  • Customized approach: Treatment should be individualized based on the severity of the condition and the patient's symptoms. Not all cases will require surgical intervention.
  • Conservative management: Many cases of Brown syndrome are mild and can be managed conservatively with observation and non-invasive treatments.
  • Monitoring: Regular and careful monitoring of visual acuity and alignment is essential, as changes may indicate a need for a change in management strategy.[5]
  • Patient comfort: Addressing discomfort associated with eye movement can improve the quality of life for patients with Brown syndrome.[9]
  • Surgical timing: If surgery is indicated, timing is crucial. Operating too early or too late can result in suboptimal outcomes.

Enhancing Healthcare Team Outcomes

The best outcomes for the patient with Brown syndrome require an interprofessional approach involving physicians, orthoptists, nurses, pharmacists, and ophthalmic technicians. The interprofessional team members guide the patient through postoperative care with instructions on correctly administering eye drops. They explain the red-flag symptoms to be aware of and the need to contact the team should these symptoms develop. The care team is involved in patient follow-up in an outpatient setting, assisting with visual acuity and orthoptic assessments.[9] Enhancing healthcare team outcomes for patients with Brown syndrome involves a collaborative, interdisciplinary approach. This ensures that all aspects of the patient's care are addressed. 

Ophthalmologists are central in diagnosis, management, and possible surgical intervention. They need to coordinate with other team members regarding the timing of interventions and ongoing care. Primary care clinicians are often the first point of contact and can help in the early identification of the syndrome. They should refer to specialists and help manage any associated systemic conditions. Pediatricians are essential for monitoring overall development and coordinating care among specialists for children with Brown syndrome.[76] Rheumatologists are crucial in cases of acquired Brown syndrome related to rheumatological conditions. Orthoptists and Optometrists assist in the non-surgical management of this condition, such as visual therapy and ensuring proper visual aids are used if necessary. Nursing staff provide patient education, ensure adherence to treatment plans, and monitor for complications or side effects of treatments.[10] Physical therapists provide exercises to maintain or improve eye mobility and address musculoskeletal compensations due to altered head postures.[77]

Regular team meetings, clear documentation, and informed consent help the interdisciplinary team function efficiently and effectively. Monitoring outcomes, continuing medical education, and incorporating patient feedback can also help improve the overall quality of medical care. Enhancing team outcomes for Brown syndrome requires a well-coordinated effort that respects the roles of various specialists and places the patient at the center of care. This approach aims to improve the management of the condition and the overall quality of life for the patient.[78]

Media


(Click Image to Enlarge)
Left Brown syndrome with hypotropia in the primary position, limited elevation and downshoot in adduction.
Left Brown syndrome with hypotropia in the primary position, limited elevation and downshoot in adduction. Contributed by Dr Lanxing Fu

References


[1]

Kaeser PF, Kress B, Rohde S, Kolling G. Absence of the fourth cranial nerve in congenital Brown syndrome. Acta ophthalmologica. 2012 Jun:90(4):e310-3. doi: 10.1111/j.1755-3768.2011.02354.x. Epub 2012 Jan 23     [PubMed PMID: 22268674]

Level 3 (low-level) evidence

[2]

Yang HK, Kim JH, Kim JS, Hwang JM. Combined Brown syndrome and superior oblique palsy without a trochlear nerve: case report. BMC ophthalmology. 2017 Aug 25:17(1):159. doi: 10.1186/s12886-017-0553-9. Epub 2017 Aug 25     [PubMed PMID: 28841851]

Level 3 (low-level) evidence

[3]

Coats DK, Paysse EA, Orenga-Nania S. Acquired Pseudo-Brown's syndrome immediately following Ahmed valve glaucoma implant. Ophthalmic surgery and lasers. 1999 May:30(5):396-7     [PubMed PMID: 10334029]

Level 3 (low-level) evidence

[4]

Hargrove RN, Fleming JC, Kerr NC. Brown's Syndrome in the absence of an intact superior oblique muscle. Journal of AAPOS : the official publication of the American Association for Pediatric Ophthalmology and Strabismus. 2004 Oct:8(5):507-8     [PubMed PMID: 15492749]


[5]

Wright KW. Brown's syndrome: diagnosis and management. Transactions of the American Ophthalmological Society. 1999:97():1023-109     [PubMed PMID: 10703149]

Level 2 (mid-level) evidence

[6]

Denis D, Lebranchu P, Beylerian M. [Brown's syndrome]. Journal francais d'ophtalmologie. 2019 Feb:42(2):189-197. doi: 10.1016/j.jfo.2018.06.012. Epub 2019 Jan 31     [PubMed PMID: 30711379]


[7]

Wilson ME, Eustis HS Jr, Parks MM. Brown's syndrome. Survey of ophthalmology. 1989 Nov-Dec:34(3):153-72     [PubMed PMID: 2694414]

Level 3 (low-level) evidence

[8]

Lee J. Management of Brown syndrome. Seminars in ophthalmology. 2008 Sep-Oct:23(5):291-3. doi: 10.1080/08820530802505971. Epub     [PubMed PMID: 19085429]

Level 2 (mid-level) evidence

[9]

Koc AA, Aygit ED, Inal A, Ocak B, Gurez C, Ahmet S, Duman B, Gokyigit B. Brown Syndrome: Features and Long-term Results of Management. Beyoglu eye journal. 2021:6(3):223-228. doi: 10.14744/bej.2021.35693. Epub 2021 Sep 27     [PubMed PMID: 35005520]


[10]

Fayed AE, Rakha NK. Case Report: Acquired Brown Syndrome after COVID-19 Vaccination. Optometry and vision science : official publication of the American Academy of Optometry. 2023 Feb 1:100(2):170-173. doi: 10.1097/OPX.0000000000001988. Epub 2023 Jan 13     [PubMed PMID: 36728177]

Level 3 (low-level) evidence

[11]

Kenawy N, Pilz DT, Watts P. Familial unilateral Brown syndrome. Indian journal of ophthalmology. 2008 Sep-Oct:56(5):430-4     [PubMed PMID: 18711279]


[12]

Urist MJ. Head tilt in vertical muscle paresis. American journal of ophthalmology. 1970 Mar:69(3):440-2     [PubMed PMID: 5418862]


[13]

von Noorden GK, Olivier P. Superior oblique tenectomy in Brown's syndrome. Ophthalmology. 1982 Apr:89(4):303-9     [PubMed PMID: 7099550]

Level 3 (low-level) evidence

[14]

Anderson RL, Baumgartner SA. Strabismus in ptosis. Archives of ophthalmology (Chicago, Ill. : 1960). 1980 Jun:98(6):1062-7     [PubMed PMID: 7387509]


[15]

Karsenti G, Karsenti D, Zaluski S, Mercadier B. [Association of Stilling-Duane syndrome and Brown's syndrome with crocodile tear syndrome and other congenital anomalies]. Bulletin des societes d'ophtalmologie de France. 1984 May:84(5):661-2     [PubMed PMID: 6534598]

Level 3 (low-level) evidence

[16]

Helveston EM, Merriam WW, Ellis FD, Shellhamer RH, Gosling CG. The trochlea. A study of the anatomy and physiology. Ophthalmology. 1982 Feb:89(2):124-33     [PubMed PMID: 7070784]


[17]

Suh SY, Le A, Demer JL. Size of the Oblique Extraocular Muscles and Superior Oblique Muscle Contractility in Brown Syndrome. Investigative ophthalmology & visual science. 2015 Sep 1:56(10):6114-20. doi: 10.1167/iovs.15-17276. Epub     [PubMed PMID: 26397461]


[18]

Miller JM. EOM Pulleys and Sequelae: A Critical Review. Investigative ophthalmology & visual science. 2019 Dec 2:60(15):5052-5058. doi: 10.1167/iovs.19-28156. Epub     [PubMed PMID: 31800963]


[19]

Demer JL, Clark RA. Letter to the Editor of IOVS From Joseph L. Demer and Robert A. Clark Regarding Joel M. Miller, "EOM Pulleys and Sequelae: A Critical Review". Investigative ophthalmology & visual science. 2020 Jun 3:61(6):10. doi: 10.1167/iovs.61.6.10. Epub     [PubMed PMID: 32503051]

Level 3 (low-level) evidence

[20]

McLoon LK, Vicente A, Fitzpatrick KR, Lindström M, Pedrosa Domellöf F. Composition, Architecture, and Functional Implications of the Connective Tissue Network of the Extraocular Muscles. Investigative ophthalmology & visual science. 2018 Jan 1:59(1):322-329. doi: 10.1167/iovs.17-23003. Epub     [PubMed PMID: 29346490]


[21]

Miller JM. Understanding and misunderstanding extraocular muscle pulleys. Journal of vision. 2007 Aug 30:7(11):10.1-15     [PubMed PMID: 17997665]

Level 3 (low-level) evidence

[22]

DeSilva M, Munoz FM, Mcmillan M, Kawai AT, Marshall H, Macartney KK, Joshi J, Oneko M, Rose AE, Dolk H, Trotta F, Spiegel H, Tomczyk S, Shrestha A, Kochhar S, Kharbanda EO, Brighton Collaboration Congenital Anomalies Working Group. Congenital anomalies: Case definition and guidelines for data collection, analysis, and presentation of immunization safety data. Vaccine. 2016 Dec 1:34(49):6015-6026. doi: 10.1016/j.vaccine.2016.03.047. Epub 2016 Jul 18     [PubMed PMID: 27435386]

Level 3 (low-level) evidence

[23]

Hermann JS, Acquired Brown's syndrome of inflammatory origin. Response to locally injected steroids. Archives of ophthalmology (Chicago, Ill. : 1960). 1978 Jul;     [PubMed PMID: 666632]

Level 3 (low-level) evidence

[24]

Galloway MT, Lalley AL, Shearn JT. The role of mechanical loading in tendon development, maintenance, injury, and repair. The Journal of bone and joint surgery. American volume. 2013 Sep 4:95(17):1620-8. doi: 10.2106/JBJS.L.01004. Epub     [PubMed PMID: 24005204]


[25]

Teodorescu L. ANOMALOUS HEAD POSTURES IN STRABISMUS AND NYSTAGMUS DIAGNOSIS AND MANAGEMENT. Romanian journal of ophthalmology. 2015 Jul-Sep:59(3):137-40     [PubMed PMID: 26978880]


[26]

Lambert SR. Late spontaneous resolution of congenital Brown syndrome. Journal of AAPOS : the official publication of the American Association for Pediatric Ophthalmology and Strabismus. 2010 Aug:14(4):373-5. doi: 10.1016/j.jaapos.2010.04.011. Epub 2010 Jul 16     [PubMed PMID: 20637665]


[27]

Jain S. Diplopia: Diagnosis and management. Clinical medicine (London, England). 2022 Mar:22(2):104-106. doi: 10.7861/clinmed.2022-0045. Epub     [PubMed PMID: 35304368]


[28]

Poonyathalang A, Khanna S, Leigh RJ. A reinterpretation of certain disorders affecting the eye muscles and their tissues. Clinical ophthalmology (Auckland, N.Z.). 2007 Dec:1(4):415-20     [PubMed PMID: 19668518]


[29]

Lang M, Faraji N, Coffey M, Badve C. MRI of acquired Brown syndrome: a report of two cases. Radiology case reports. 2018 Feb:13(1):92-95. doi: 10.1016/j.radcr.2017.09.025. Epub 2017 Oct 31     [PubMed PMID: 29487642]

Level 3 (low-level) evidence

[30]

Ji SY, Yoo JH, Ha W, Lee JW, Yang WS. Three cases of acquired simulated brown syndrome after blowout fracture operations. Archives of plastic surgery. 2015 May:42(3):346-50. doi: 10.5999/aps.2015.42.3.346. Epub 2015 May 14     [PubMed PMID: 26015892]

Level 3 (low-level) evidence

[31]

Batailler C, Neyret P. Trochlear dysplasia: imaging and treatment options. EFORT open reviews. 2018 May:3(5):240-247. doi: 10.1302/2058-5241.3.170058. Epub 2018 May 21     [PubMed PMID: 29951262]


[32]

Heo S, Park SY, Seo J, Koh SH, Lee IJ. Diffuse-Type Tenosynovial Giant Cell Tumor of the Tendon Sheath in Both Wrists. Taehan Yongsang Uihakhoe chi. 2021 Jan:82(1):250-254. doi: 10.3348/jksr.2020.0055. Epub 2020 Dec 10     [PubMed PMID: 36237452]


[33]

Alonso-Valdivielso JL, Alvarez Lario B, Alegre López J, Sedano Tous MJ, Buitrago Gómez A. Acquired Brown's syndrome in a patient with systemic lupus erythematosus. Annals of the rheumatic diseases. 1993 Jan:52(1):63-4     [PubMed PMID: 8427518]


[34]

Wynn TA. Cellular and molecular mechanisms of fibrosis. The Journal of pathology. 2008 Jan:214(2):199-210     [PubMed PMID: 18161745]


[35]

Shah KK, Pritt BS, Alexander MP. Histopathologic review of granulomatous inflammation. Journal of clinical tuberculosis and other mycobacterial diseases. 2017 May:7():1-12. doi: 10.1016/j.jctube.2017.02.001. Epub 2017 Feb 10     [PubMed PMID: 31723695]


[36]

Eneh A, Johnson D, Schweitzer K, Strube YNJ. Brown's syndrome during pregnancy: a case report and review of literature. Canadian journal of ophthalmology. Journal canadien d'ophtalmologie. 2018 Dec:53(6):e256-e258. doi: 10.1016/j.jcjo.2018.02.007. Epub 2018 May 3     [PubMed PMID: 30503010]

Level 3 (low-level) evidence

[37]

Pawar N, Ravindran M, Ramakrishnan R, Maheshwari D, Trivedi B. Unilateral acquired Brown's syndrome in systemic scleroderma: An unusual cause for diplopia. Indian journal of ophthalmology. 2015 Nov:63(11):861-3. doi: 10.4103/0301-4738.171971. Epub     [PubMed PMID: 26669341]


[38]

Tejada P, Enríquez E, Rodríguez del Valle JM, Barceló A, Gutiérrez E, de Inocencio J. Juvenile idiopathic arthritis-associated uveitis complicated by glaucoma and Brown's syndrome. Rheumatology (Oxford, England). 2012 Sep:51(9):1729-30. doi: 10.1093/rheumatology/kes069. Epub 2012 Apr 6     [PubMed PMID: 22491719]

Level 3 (low-level) evidence

[39]

White VA, Cline RA. Pathologic causes of the superior oblique click syndrome. Ophthalmology. 1999 Jul:106(7):1292-5     [PubMed PMID: 10406608]

Level 3 (low-level) evidence

[40]

Bandyopadhyay R, Shetty S, Vijayalakshmi P. Surgical outcome in monocular elevation deficit: a retrospective interventional study. Indian journal of ophthalmology. 2008 Mar-Apr:56(2):127-33     [PubMed PMID: 18292623]

Level 2 (mid-level) evidence

[41]

Akbari MR, Khorrami-Nejad M, Kangari H, Akbarzadeh Baghban A, Ranjbar Pazouki M. Ocular Abnormal Head Posture: A Literature Review. Journal of current ophthalmology. 2021 Oct-Dec:33(4):379-387. doi: 10.4103/joco.joco_114_20. Epub 2022 Jan 6     [PubMed PMID: 35128182]


[42]

Lee WJ, Kim JH, Shin YU, Hwang S, Lim HW. Differences in eye movement range based on age and gaze direction. Eye (London, England). 2019 Jul:33(7):1145-1151. doi: 10.1038/s41433-019-0376-4. Epub 2019 Mar 5     [PubMed PMID: 30837710]


[43]

Hatt S, Antonio-Santos A, Powell C, Vedula SS. Interventions for stimulus deprivation amblyopia. The Cochrane database of systematic reviews. 2006 Jul 19:(3):CD005136     [PubMed PMID: 16856079]

Level 1 (high-level) evidence

[44]

Oystreck DT, Engle EC, Bosley TM. Recent progress in understanding congenital cranial dysinnervation disorders. Journal of neuro-ophthalmology : the official journal of the North American Neuro-Ophthalmology Society. 2011 Mar:31(1):69-77. doi: 10.1097/WNO.0b013e31820d0756. Epub     [PubMed PMID: 21317732]

Level 3 (low-level) evidence

[45]

Irving EL, Harris JD, Machan CM, Robinson BE, Hrynchak PK, Leat SJ, Lillakas L. Value of Routine Eye Examinations in Asymptomatic Patients. Optometry and vision science : official publication of the American Academy of Optometry. 2016 Jul:93(7):660-6. doi: 10.1097/OPX.0000000000000863. Epub     [PubMed PMID: 27058591]


[46]

Chang MY, Coleman AL, Tseng VL, Demer JL. Surgical interventions for vertical strabismus in superior oblique palsy. The Cochrane database of systematic reviews. 2017 Nov 27:11(11):CD012447. doi: 10.1002/14651858.CD012447.pub2. Epub 2017 Nov 27     [PubMed PMID: 29178265]

Level 1 (high-level) evidence

[47]

Tong J, Huang J, Khou V, Martin J, Kalloniatis M, Ly A. Topical Review: Assessment of Binocular Sensory Processes in Low Vision. Optometry and vision science : official publication of the American Academy of Optometry. 2021 Apr 1:98(4):310-325. doi: 10.1097/OPX.0000000000001672. Epub     [PubMed PMID: 33828038]


[48]

Metz HS. Forced duction, active force generation, and saccadic velocity tests. International ophthalmology clinics. 1976 Fall:16(3):47-73     [PubMed PMID: 786926]


[49]

Martin R. Cornea and anterior eye assessment with slit lamp biomicroscopy, specular microscopy, confocal microscopy, and ultrasound biomicroscopy. Indian journal of ophthalmology. 2018 Feb:66(2):195-201. doi: 10.4103/ijo.IJO_649_17. Epub     [PubMed PMID: 29380757]


[50]

Visioli G, Zeppieri M, Iannucci V, Manni P, Albanese GM, Salati C, Spadea L, Pirraglia MP. From Bedside to Diagnosis: The Role of Ocular Fundus in Systemic Infections. Journal of clinical medicine. 2023 Nov 21:12(23):. doi: 10.3390/jcm12237216. Epub 2023 Nov 21     [PubMed PMID: 38068267]


[51]

Vesely P, Synek S. Simple binocular vision examination on synoptophore determination of normative database of healthy adult subjects examination of binocular vision on synoptophore. Collegium antropologicum. 2013 Apr:37 Suppl 1():145-51     [PubMed PMID: 23837235]


[52]

Kekunnaya R, Mendonca T, Sachdeva V. Pattern strabismus and torsion needs special surgical attention. Eye (London, England). 2015 Feb:29(2):184-90. doi: 10.1038/eye.2014.270. Epub 2014 Nov 21     [PubMed PMID: 25412718]


[53]

Michels KL, Kurup SP, Curran ML, Alperin R, De Leon E, Mets-Halgrimson R. A case of acquired Brown syndrome treated with adalimumab. Journal of AAPOS : the official publication of the American Association for Pediatric Ophthalmology and Strabismus. 2020 Jun:24(3):167-169. doi: 10.1016/j.jaapos.2020.01.003. Epub 2020 Feb 20     [PubMed PMID: 32087325]

Level 3 (low-level) evidence

[54]

Parks MM, Eustis HS. Simultaneous superior oblique tenotomy and inferior oblique recession in Brown's syndrome. Ophthalmology. 1987 Aug:94(8):1043-8     [PubMed PMID: 3658365]


[55]

Wright KW. Superior oblique silicone expander for Brown syndrome and superior oblique overaction. Journal of pediatric ophthalmology and strabismus. 1991 Mar-Apr:28(2):101-7     [PubMed PMID: 2051286]

Level 2 (mid-level) evidence

[56]

Rajamani M, Nagasubramanian V, Devaraj C, Dandapani R. Recurrent Brown's Syndrome after Superior Oblique Tendon Recession Treated by Silicone Spacer. Strabismus. 2016 Sep:24(3):106-8. doi: 10.1080/09273972.2016.1205105. Epub 2016 Aug 2     [PubMed PMID: 27485546]


[57]

Caldeira JA. Bilateral recession of the superior oblique in "A" pattern tropia. Journal of pediatric ophthalmology and strabismus. 1978 Sep-Oct:15(5):306-11. doi: 10.3928/0191-3913-19780901-12. Epub     [PubMed PMID: 24877301]


[58]

Moghadam AA, Sharifi M, Heydari S. The results of Brown syndrome surgery with superior oblique split tendon lengthening. Strabismus. 2014 Mar:22(1):7-12. doi: 10.3109/09273972.2013.877943. Epub     [PubMed PMID: 24564724]

Level 3 (low-level) evidence

[59]

Kokubo K, Katori N, Kasai K, Hayashi K, Kamisasanuki T. Trochlea surgery for acquired Brown syndrome. Journal of AAPOS : the official publication of the American Association for Pediatric Ophthalmology and Strabismus. 2014 Feb:18(1):56-60. doi: 10.1016/j.jaapos.2013.10.023. Epub     [PubMed PMID: 24568984]

Level 3 (low-level) evidence

[60]

Sato SE, Ellis FD, Pinchoff BS, Helveston EM, Rummel JH. Superior oblique overaction in patients with true Brown's syndrome. Journal of pediatric ophthalmology and strabismus. 1987 Nov-Dec:24(6):282-6     [PubMed PMID: 3694383]


[61]

Xia W, Wei Y, Wu L, Zhao C. Congenital Fibrosis of the Extraocular Muscles: An Overview from Genetics to Management. Children (Basel, Switzerland). 2022 Oct 22:9(11):. doi: 10.3390/children9111605. Epub 2022 Oct 22     [PubMed PMID: 36360333]

Level 3 (low-level) evidence

[62]

Assaf AA. Congenital innervation dysgenesis syndrome (CID)/congenital cranial dysinnervation disorders (CCDDs). Eye (London, England). 2011 Oct:25(10):1251-61. doi: 10.1038/eye.2011.38. Epub 2011 Jul 1     [PubMed PMID: 21720410]


[63]

Juel VC, Massey JM. Myasthenia gravis. Orphanet journal of rare diseases. 2007 Nov 6:2():44     [PubMed PMID: 17986328]


[64]

Chen AC, Velez FG, Pineles SL. Severe Acquired Restrictive Strabismus Fixus in Patients with Trisomy 21. Journal of binocular vision and ocular motility. 2019 Oct-Dec:69(4):153-156. doi: 10.1080/2576117X.2019.1663113. Epub 2019 Oct 4     [PubMed PMID: 31584357]


[65]

Özkan SB. Restrictive problems related to strabismus surgery. Taiwan journal of ophthalmology. 2016 Jul-Sep:6(3):102-107. doi: 10.1016/j.tjo.2016.05.001. Epub 2016 Jun 20     [PubMed PMID: 29018723]


[66]

Pakdaman MN, Sepahdari AR, Elkhamary SM. Orbital inflammatory disease: Pictorial review and differential diagnosis. World journal of radiology. 2014 Apr 28:6(4):106-15. doi: 10.4329/wjr.v6.i4.106. Epub     [PubMed PMID: 24778772]


[67]

Cooymans P, Al-Zuhaibi S, Al-Senawi R, Ganesh A. Congenital fibrosis of the extraocular muscles. Oman journal of ophthalmology. 2010 May:3(2):70-4. doi: 10.4103/0974-620X.64230. Epub     [PubMed PMID: 21217899]


[68]

Chhablani PP, Chandrasekharan A. Resolution of acquired Brown syndrome with oral steroid therapy. Oman journal of ophthalmology. 2017 May-Aug:10(2):128-130. doi: 10.4103/ojo.OJO_4_2016. Epub     [PubMed PMID: 28757707]

Level 3 (low-level) evidence

[69]

Aylward GW, Lawson J, McCarry B, Lee JP, Fells P. The surgical treatment of traumatic Brown syndrome. Journal of pediatric ophthalmology and strabismus. 1992 Sep-Oct:29(5):276-83     [PubMed PMID: 1432513]

Level 3 (low-level) evidence

[70]

Cho YA, Kim S, Graef MH. Surgical outcomes in correction of Brown syndrome. Korean journal of ophthalmology : KJO. 2006 Mar:20(1):33-40     [PubMed PMID: 16768188]


[71]

Mackintosh NJ, Davis RE, Easter A, Rayment-Jones H, Sevdalis N, Wilson S, Adams M, Sandall J. Interventions to increase patient and family involvement in escalation of care for acute life-threatening illness in community health and hospital settings. The Cochrane database of systematic reviews. 2020 Dec 8:12(12):CD012829. doi: 10.1002/14651858.CD012829.pub2. Epub 2020 Dec 8     [PubMed PMID: 33285618]

Level 1 (high-level) evidence

[72]

. Assessing and managing eye injuries. Community eye health. 2005 Oct:18(55):101-4     [PubMed PMID: 17491766]


[73]

Manley DR, Alvi RA. Brown's syndrome. Current opinion in ophthalmology. 2011 Sep:22(5):432-40. doi: 10.1097/ICU.0b013e328349b0ca. Epub     [PubMed PMID: 21825991]

Level 3 (low-level) evidence

[74]

Kumar SP, Jim A. Physical therapy in palliative care: from symptom control to quality of life: a critical review. Indian journal of palliative care. 2010 Sep:16(3):138-46. doi: 10.4103/0973-1075.73670. Epub     [PubMed PMID: 21218003]

Level 2 (mid-level) evidence

[75]

Kruk ME, Gage AD, Arsenault C, Jordan K, Leslie HH, Roder-DeWan S, Adeyi O, Barker P, Daelmans B, Doubova SV, English M, García-Elorrio E, Guanais F, Gureje O, Hirschhorn LR, Jiang L, Kelley E, Lemango ET, Liljestrand J, Malata A, Marchant T, Matsoso MP, Meara JG, Mohanan M, Ndiaye Y, Norheim OF, Reddy KS, Rowe AK, Salomon JA, Thapa G, Twum-Danso NAY, Pate M. High-quality health systems in the Sustainable Development Goals era: time for a revolution. The Lancet. Global health. 2018 Nov:6(11):e1196-e1252. doi: 10.1016/S2214-109X(18)30386-3. Epub 2018 Sep 5     [PubMed PMID: 30196093]

Level 2 (mid-level) evidence

[76]

Rajendran L. "Teamwork makes the dream work"- interdisciplinary team dynamics within the operating room. Canadian medical education journal. 2022 Mar:13(1):108. doi: 10.36834/cmej.74102. Epub 2022 Mar 2     [PubMed PMID: 35291460]


[77]

Kim D, Cho M, Park Y, Yang Y. Effect of an exercise program for posture correction on musculoskeletal pain. Journal of physical therapy science. 2015 Jun:27(6):1791-4. doi: 10.1589/jpts.27.1791. Epub 2015 Jun 30     [PubMed PMID: 26180322]


[78]

Wong E, Mavondo F, Fisher J. Patient feedback to improve quality of patient-centred care in public hospitals: a systematic review of the evidence. BMC health services research. 2020 Jun 11:20(1):530. doi: 10.1186/s12913-020-05383-3. Epub 2020 Jun 11     [PubMed PMID: 32527314]

Level 1 (high-level) evidence