Original articleHypoplastic Oculomotor Nerve and Absent Abducens Nerve in Congenital Fibrosis Syndrome and Synergistic Divergence with Magnetic Resonance Imaging
Section snippets
Materials and Methods
Institutional review board approval was not required for this study. Informed consent was obtained from the patient in case 1 and from the father in case 2. Magnetic resonance imaging was conducted using a 1.5-tesla system (Gyroscan Intera, Philips, Best, The Netherlands) with a SENSE (sensitivity encoding) head coil and a 3-dimensional balanced turbo field echo sequence. Scanning was performed in an axial plane including the pons and medulla oblongata to visualize the cisternal segment of the
Case 1
A 19-year-old man was referred to our institution for the evaluation of exotropia. The patient was born after an uneventful full-term pregnancy and delivery. He reported that his mother also had exotropia and ptosis.
On ophthalmologic evaluation, his visual acuities (VAs) were 20/30 in both eyes. He had chin up and a mild head turn to the right. He had 75 prism diopters (PD) of exotropia in the primary position, which increased to over 100 PD in both the left and right gaze. Both eyes were fixed
Discussion
Synergistic divergence has been considered a variant of DRS.1, 2, 3, 4, 5 Synergistic divergence can also be produced secondarily in patients with various forms of DRS by recession of the medial rectus muscles (ocular splits).4, 17, 18 Even though there has been no pathologic report of synergistic divergence, pathologic reports of DRS showed that abducens nuclei and nerves were hypoplastic or absent from the brainstem.19, 20, 21, 22 Postmortem neuropathologic examination of one patient with
References (22)
- et al.
Congenital adduction palsy and synergistic divergence
Am J Ophthalmol
(1981) - et al.
Congenital unilateral adduction deficit with simultaneous abductionA variant of Duane's retraction syndrome
Ophthalmology
(1987) - et al.
Absence of the abducens nerve in Duane syndrome verified by magnetic resonance imaging
Am J Ophthalmol
(1998) Hereditary external ophthalmoplegia synergistic divergence, jaw winking, and oculocutaneous hypopigmentation: a congenital fibrosis syndrome caused by deficient innervation to extraocular muscles
Ophthalmology
(1998)- et al.
Congenital fibrosis of the vertically acting extraocular musclesA new group of dominantly inherited ocular fibrosis with radiologic findings
Ophthalmology
(1995) - et al.
Congenital fibrosis of the extraocular muscles associated with cortical dysplasia and maldevelopment of the basal ganglia
Ophthalmology
(2001) - et al.
Synergistic divergence: saccadic velocity analysis and surgical results
J Pediatr Ophthalmol Strabismus
(1992) - et al.
Pediatric Neuro-ophthalmology
(1996) - et al.
Congenital adduction palsy and synergistic divergence: a clinical and electro-oculographic study
Br J Ophthalmol
(1989) - et al.
MRI of Duane's retraction syndrome; absence of the abducens nerve
Neuroophthalmol Jpn
(2003)
Magnetic resonance imaging in Duane's retraction syndrome
J Pediatr Ophthalmol Strabismus
Cited by (62)
Eye Movement Disorders: Third, Fourth, and Sixth Nerve Palsies and Other Causes of Diplopia and Ocular Misalignment
2018, Liu, Volpe, and Galetta's Neuro-Ophthalmology: Diagnosis and ManagementSynergistic innervational downshoot: a distinct vertical dysinnervation pattern and its unique management
2017, Canadian Journal of OphthalmologyMRI findings in Duane's ocular retraction syndrome
2014, Clinical RadiologyAuthor reply
2013, OphthalmologyCongenital Orbital Fibrosis with Spontaneous Regression of Orbital Tumor
2023, Ophthalmic Plastic and Reconstructive SurgeryA Treatment Approach in Congenital Fibrosis of Extraocular Muscles
2023, Medical Archives
Manuscript no. 2004-50.
The authors have no financial conflict of interest regarding this article's subject matter.