Acquired Brown's syndrome: an unusual cause

[Superior oblique tendon trochlear passage syndrome : Causes, motility findings and treatment of acquired Jaensch-Brown syndrome]

CLINICAL FEATURES

Acquired Jaensch-Brown syndrome is characterized by a mechanical limitation of elevation in adduction, with orthophoria in downward gaze. It was first described by Jaensch in 1928 after orbital trauma in his case and has the same motility pattern as congenital Brown's syndrome. For this reason, in 1973 Brown differentiated between the "true" and "simulated" cases. Further clinical findings of the different etiological factors must be considered in order to differentiate between the two groups.

ORIGIN

The cause is an acquired restriction of the free passage of the superior oblique tendon through the trochlea. In most cases this is produced by a palpable swelling/nodule of the superior oblique tendon posterior to the trochlea. There are three possibilities to develop a swelling/nodule: 1. Shortly after birth due to an incomplete development at the time of birth of the sliding factors needed for a free passage. 2. An inflammation in combination with a systemic disease, such as rheumatism or idiopathic. 3. A blunt orbital trauma causing a hematoma of the superior oblique tendon. Additionally, the trochlear passage can be narrowed by a severe inflammation involving the trochlea, which is associated with a swelling and marked tenderness of the trochlear area and corresponds to stenosing tenosynovitis of the hand.

TREATMENT

The therapeutic management of these four variations differs significantly depending on the cause of the swelling.

CONCLUSION

The swelling of the superior oblique tendon posterior to the trochlea explains the motility disorder in acquired Jaensch-Brown syndrome. There are three different causes for the swelling, which require different therapeutic management.

The "Eyelet Sign" as an MRI Clue for Inflammatory Brown Syndrome

BACKGROUND

Brown syndrome is characterized by a restrictive elevation deficit of the affected eye in adduction. Besides the well-known congenital form, different acquired etiologies including inflammation, trauma, and surgery may prevent the superior oblique (SO) tendon from gliding freely through the trochlea on attempted upgaze. We present MRI findings in pediatric and adult patients with inflammatory acquired Brown syndrome.

METHODS

Retrospective review of clinical and MRI findings of 6 patients (4 children: median age 8.4 years [range 6.1-8.7]; 2 adults: age 46.4 and 51.1 years). Median follow-up was 23 months (range 1-52).

RESULTS

In all 6 patients, orbital MRI demonstrated inflammatory changes of the SO tendon-trochlea complex. A striking feature was circumferential contrast enhancement of the trochlea with central sparing where the tendon passes, reminiscent of an eyelet. In all cases, the motility restriction improved either spontaneously or with systemic anti-inflammatory treatment. Although both adult patients had a history of known seronegative spondyloarthritis, there was no associated systemic condition in the children in our series.

CONCLUSIONS

Both in children and in adults, MRI can provide evidence of inflammatory changes located at the trochlea-tendon complex in acquired Brown syndrome here referred to as the "eyelet sign," which may be helpful in confirming the clinical diagnosis and guide appropriate treatment.

Monocular partial/sector occlusion therapy: a procedure to inhibit diplopia in Brown syndrome

BACKGROUND

Brown syndrome is recognized clinically as an absence or restriction of elevation in adduction. It often causes intermittent diplopia.

CASE REPORT

This article includes discussion of a child, age 3 years, 11 months, who underwent surgery of the right eye for a left hypertropia. By age 5 years, he complained to his mother of daily, intermittent diplopia, eye pain in both eyes (OU), and frontal headaches. Additional strabismus surgeries OU were done at ages 6¾ years and 8¼ years. At age 10½ years, the ophthalmologist first noted suspicion of acquired right Brown syndrome, which was definitively diagnosed at age 14. At that time, the original complaints remained unresolved, and his mother was hesitant to allow a fourth surgery. Thus, a procedure was devised to partially occlude a precise sector of the spectacle lens for the noninvolved eye in Brown syndrome. This successfully inhibited the daily, intermittent diplopia while allowing fusion and normal stereopsis in primary and down gaze. Also, it resolved the associated eye pain OU and headaches.

CONCLUSION

Monocular partial/sector occlusion therapy to inhibit intermittent diplopia in Brown syndrome offers a sensible alternative to surgery for those with normal or near-normal alignment, fusion, and stereopsis in primary and down gaze. For those who contemplate surgery, had failed surgery, or require treatment of underlying disease, monocular partial/sector occlusion therapy can serve as an excellent adjunct. Also, it may be attempted in other incomitant strabismic deviations with bothersome diplopia limited to specific positions of gaze.

Pathologic causes of the superior oblique click syndrome

PURPOSE

To describe the clinical features in two patients with superior oblique click syndrome and the pathologic causes of their symptoms.

DESIGN

Two observational case reports.

PARTICIPANTS

Two patients.

METHODS

The clinical histories, results of physical examinations, treatment, and pathologic findings in two patients with superior oblique click syndrome are reviewed and analyzed with reference to the literature.

MAIN OUTCOME MEASURES

Relief of symptoms.

RESULTS

Both patients were operated on; one was found to have a schwannoma and the other a giant cell tumor of tendon sheath as causes of their symptoms. Symptoms were relieved by removal of the lesions and have not recurred.

CONCLUSION

Definite pathologic lesions may cause the superior oblique click syndrome.

Brown's syndrome: diagnosis and management

PURPOSE

To better understand the various etiologies of Brown's syndrome, define specific clinical characteristics of Brown's syndrome, describe the natural history of Brown's syndrome, and evaluate the longterm outcome of a novel surgical procedure: the silicone tendon expander. Also, to utilize a computer model to simulate the pattern of strabismus seen clinically with Brown's syndrome and manipulate the model to show potential surgical outcomes of the silicone tendon expander.

METHODS

Charts were reviewed on patients with the diagnosis of Brown's syndrome seen at a children's hospital ophthalmology clinic from 1982 to 1997, or seen in the author's private practice. Objective fundus torsion was assessed in up gaze, down gaze, and primary position in 7 Brown's syndrome patients and in 4 patients with primary superior oblique overaction. A fax survey was taken of members of the American Association of Ophthalmology and Strabismus (AAPOS) listed in the 1997-1998 directory regarding their results using the silicone tendon expander procedure for the treatment of Brown's syndrome. A computer model of Brown's syndrome was created using the Orbit 1.8 program by simulating a shortened superior oblique tendon or by changing stretch sensitivity to create an inelastic muscle.

RESULTS

A total of 96 patients were studied: 85 with Brown's syndrome (38 with congenital and 47 with acquired disease), 6 with masquerade syndromes, 1 with Brown's syndrome operated on elsewhere, and 4 with primary superior oblique overaction in the torsion study. Three original clinical observations were made: 1. Significant limitation of elevation in abduction occurs in 70% of Brown's syndrome cases surgically verified as caused by a tight superior oblique tendon. Contralateral pseudo-inferior oblique overaction is associated with limited elevation in abduction. 2. Traumatic Brown's syndrome cases have larger hypotropias than nontraumatic cases (P < .001). There was no significant hypotropia in primary position in 56 (76%) of 74 congenital and nontraumatic acquired cases despite severe limitation of elevation. 3. Of 7 patients with Brown's syndrome, 6 had no significant fundus torsion in primary position, but had significant (+2 to +3) intorsion in up gaze. Spontaneous resolution occurred in approximately 16% of acquired nontraumatic Brown's syndrome patients. The silicone tendon expander was used on 15 patients, 13 (87%) were corrected with 1 surgery and 14 (93%) with 2 surgeries. The only failure was a Brown's syndrome not caused by superior oblique pathology. Five of the silicone tendon expander patients had at least 5 years follow-up (range, 5 to 11 years). Four (80%) of the 5 patients had an excellent outcome with 1 surgery, final results graded between 9 and 10 (on a scale of 1-10, 10 is best). The fifth patient had a consecutive superior oblique paresis and a good outcome after a recession of the ipsilateral inferior oblique muscle. The AAPOS survey had a mean outcome score of 7.3, with 65% between 8 and 10. There were 9 (6%) complications reported: 4 related to scarring and 5 extrusions of the implant. Three of the 5 extrusions were reported from the same surgeon. The computer model of an inelastic superior oblique muscle-tendon complex best simulated the motility pattern of Brown's syndrome with severe limitation of elevation in adduction, mild limitation of elevation in abduction, minimal hypotropia in primary position, no superior oblique overaction, and intorsion in up gaze.

CONCLUSIONS

The presence of mild to moderate limitation of elevation in abduction is common, and its presence does not eliminate the diagnosis of Brown's syndrome. The majority of Brown's syndrome patients have a pattern of strabismus consistent with an inelastic superior oblique muscle-tendon complex that does not extend, but can contract normally; not the presence of a short tendon. The presence of inelastic or tethered superior oblique muscle-tendon can be diagnosed without forced duction testing by observing the pattern of strabismus including torsion. Because of the chance for spontaneous resolution, conservative management, not surgery, should be the first line of treatment for acquired Brown's syndrome. If surgery is indicated, a novel procedure, the silicone tendon expander, is an effective option with excellent long-term outcomes.

Superior oblique luxation and trochlear luxation as new concepts in superior oblique muscle weakening surgery

PURPOSE

We used superior oblique luxation and trochlear luxation as new surgical procedures to treat acquired Brown's syndrome and superior oblique muscle overaction.

METHODS

We studied nine patients (11 eyes) who underwent trochlear surgery between 1988 and 1993. Four patients had acquired Brown's syndrome and five had superior oblique muscle overaction. In five patients (six eyes) the trochlea was incised to luxate the superior oblique tendon out of the trochlea. In four patients (five eyes) the trochlea was luxated out of its fossa via a periosteal approach without opening the trochlea itself.

RESULTS

The mean follow-up was 18 months (range, nine to 33 months). Postoperatively, eight patients showed subjective and objective improvement. One patient with painful traumatic acquired Brown's syndrome had no objective improvement but obtained relief of pain.

CONCLUSIONS

These new techniques are a successful alternative in the treatment of acquired Brown's syndrome and superior oblique muscle overaction.

Acquired Brown's syndrome: iatrogenic causes

Two cases of iatrogenic acquired Brown's syndrome are presented, and other causes of this disorder and its treatment are discussed. Care should be taken not to cause damage when operating in the region of the trochlea.

Brown's syndrome

Brown's syndrome is a well-recognized clinical disorder of ocular motility manifesting most notably a restriction of active and passive elevation in adduction. The original name, "superior oblique tendon sheath syndrome," is no longer appropriate, since it has been shown that the tissue surrounding the anterior superior oblique tendon is blameless as a restrictive force. "True" and "simulated" as descriptive modifiers should also be discarded, as they relate to the disproven sheath concept. Brown's syndrome occurs as a congenital or acquired, constant or intermittent condition; the common link is restriction of free movement through the trochlea pulley mechanism. The various etiologic theories are reviewed and the spectrum of medical and surgical treatments are described and evaluated. Evidence suggests that subtypes of Brown's syndrome lie on a single continuum and that spontaneous resolution occurs in each group, probably more often than previously recognized. A simplified classification scheme is encouraged and possible future directions in Brown's syndrome research are introduced.

Acquired Brown's syndrome associated with Hurler-Scheie's syndrome

A 5-year-old Caucasian girl with known Hurler-Scheie's syndrome (mucopolysaccharidosis) developed a right Brown's syndrome while under orthoptic review. There was no evidence of trauma or inflammation of the superior oblique tendon, trochlea, or surrounding tissues. The Brown's syndrome in this case may be due to shortening of the superior oblique tendon, associated with the shortening of long tendons of the arms and feet, which is common in Hurler-Scheie's syndrome.

Simulated superior oblique tendon sheath syndrome

Three patients with simulated Brown's superior oblique tendon sheath syndrome are presented. With the use of computed tomographic (CT) findings, the site of the pathology could be demonstrated. In all three patients, there were definite abnormal findings in the anterior sheath of the reflected tendon of the superior oblique. The abnormal findings in one case were confirmed at the time of surgery. Therapy in two of the cases was determined by the abnormal findings on the CT scan.

Orbital injury complicated by entrapment of the superior oblique tendon: a case report

Fractures of the orbital roof are rare. Entrapment of the extraocular muscles in such fractures has not, to our knowledge, been reported previously. A case of acquired Brown's syndrome due to entrapment of the superior oblique muscle tendon in an orbital roof fracture is reported.

Acquired Brown's syndrome in a patient with combined lichen sclerosus et atrophicus and morphoea

A 49-year-old woman with generalised lichen sclerosus et atrophicus and morphoea developed bilateral Brown's syndrome. Some of the skin lesions were in the vicinity of the trochlea. A characteristic feature of morphoea is subcutaneous fibrosis, so we postulate that the cause of the Brown's syndrome was mechanical tethering of the superior oblique tendon by deep subdermal fibrosis. Histopathological diagnosis was made from biopsies of similar lesions on the patient's face.