Tendon elongation with bovine pericardium in strabismus surgery—indications beyond Graves’ orbitopathy

Background For some patients with complex ocular motility disorders, conventional strabismus surgery is insufficient. Surgery with tendon elongation allows correction of larger angles and maintains a sufficient arc of contact for rectus muscles. This study reports results for tendon elongation with bovine pericardium (Tutopatch®) in indications other than Graves’ orbitopathy in which it is already widely used. Methods We reviewed the records of all patients who underwent surgery with Tutopatch® in our institution. Angles of squint and head postures were analyzed preoperatively, on the first postoperative day, and in the long term (median 9 weeks after the operation). Patients with Graves’ orbitopathy were excluded. Results From 2011 to 2018, the procedures on 58 eyes of 54 patients (35 females, median age 35 years (3–75)) met the inclusion criteria. Horizontal rectus muscle surgery (53 eyes) was conducted on patients with residual strabismus (13), Duane’s retraction syndrome with eso- (type I: 16)/exodeviation (type II: 2, type III: 1), 6th (7)/3rd nerve palsy (7), Möbius syndrome (2), congenital fibrosis of the extraocular muscles type 3A (CFEOM3A, TUBB3 mutation) (4), and orbital apex syndrome (1). Vertical rectus muscle surgery (5 eyes) was conducted on patients with myasthenia (1), vertical tropia after orbital floor fracture (1), CFEOM1 (2), and Parry-Romberg syndrome (1). 42 eyes had prior eye muscle surgery (1–5 procedures, median 1). Out of 45 patients with postoperative long-term data, 43 showed an angle reduction. Fifty-one percent had an angle of 10Δ (prism diopter) or less, one had a significant over-effect, and 10 had revision surgery. For the heterogeneous group of residual eso- and exotropias, the median absolute horizontal angle was reduced from 35Δ (16 to 45Δ) to 9Δ (0 to 40Δ), for Duane’s retraction syndrome from 27.5Δ (9 to 40Δ) to 7Δ (0 to 40Δ), and for sixth and third nerve palsies from 43Δ (20 to 75Δ) to 18Δ (4 to 40Δ). For 3 patients with vertical rectus muscle surgery, the median absolute vertical angle was reduced from 30Δ (20 to 45Δ) to 4Δ (1 to 22Δ). The motility range was shifted in the direction contrary to the elongated muscle in all subgroups. A considerable reduction of the excursion into the field of action of the elongated muscle had to be registered. Conclusions Strabismus surgery with bovine pericardium introduces new surgical options for complicated revisions and for rare and complex oculomotor dysfunctions. Yet, it has to be recognized that this type of surgery aiming at maximum effects, despite preservation or restitution of the arc of contact, leads to reduction of the excursion into the field of action of the elongated muscle. Furthermore, dose finding can be difficult depending on the underlying pathology and more than one intervention might be necessary for optimal results.

Pseudo-Duane’s retraction syndrome: a rare clinical entity

<p class="abstract">Studies of sequelae of isolated medial orbital wall fractures show that the majority of patients with this condition are often asymptomatic, which makes the diagnosis based only on clinical grounds difficult. One of the rare complications of this entity is Pseudo-Duane’s retraction syndrome, which is characterised by horizontal diplopia, restricted abduction with or without limited adduction, accompanied by narrowing of the palpebral fissure, globe retraction and pseudo ptosis on abduction. This is a case report of a 46-year-old female who developed Pseudo-Duane’s retraction syndrome following trauma to her left orbit. She presented with left eye pain, diplopia, horizontal gaze restrictions, left eye ecchymosis and enophthalmos. Careful history taking and thorough ophthalmic examination including forced duction test along with radiological imaging helped clinch this diagnosis. Timely intervention by an endoscopic approach to release the medial rectus muscle entrapped within the fracture resolved the patient’s symptoms.</p>

Morphometry of the Oculomotor Nerve in Duane’s Retraction Syndrome

Objective: To investigate the morphometric characteristics of the oculomotor nerve and its association with horizontal rectus muscle volume in patients with Duane’s retraction syndrome (DRS) according to the presence of the abducens nerve. Methods: Fifty patients diagnosed with unilateral DRS were divided into two groups according to high-resolution magnetic resonance imaging (MRI) findings; DRS without an abducens nerve on the affected side (absent group, n = 41), and DRS with symmetric abducens nerves on both sides (present group, n = 9). Oculomotor nerve diameter was measured on high-resolution MRI in the middle of the cisternal space. The medial rectus muscle (MR) and lateral rectus muscle (LR) volumes were measured on T2-weighted coronal MRI of the orbit. Associations of oculomotor nerve diameter and horizontal rectus muscle volumes were performed according to the presence and absence of the abducens nerve. Results: Oculomotor nerve diameter on the affected side was thicker than that of the non-affected side in the absent group (p < 0.001), but not in the present group (p = 0.623). In the absent group, there was a positive correlation between oculomotor nerve diameter and MR volume (r = 0.779, p < 0.001), as well as the LR volume (r = 668, p = 0.023) of the affected eye. Conclusions: In DRS patients with an absent abducens nerve, the oculomotor nerve diameter was thicker in the affected eye compared to the non-affected eye. Oculomotor nerve diameter was associated with MR and LR volumes in the absent group. This study provides structural correlates of aberrant innervation of the oculomotor nerve in DRS patients.