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Updated: Jul 15, 2026
10:49
Ocular Kinematics Measured by In Vitro Stimulation of the Cranial Nerves in the Turtle
Published on: June 2, 2018
Primary superior oblique muscle-levator muscle synkinesis
Mihir Kothari1, Ali Hussain, Dharmesh Kar
1Aditya Jyot Eye Hospital, Wadala, Maharashtra, India. drmihirkothari@yahoo.com <drmihirkothari@yahoo.com>
Summary
Congenital ocular aberrant innervations are rare, typically not involving the trochlear nerve. This case presents a rare instance of superior oblique-levator muscle synkinesis causing eyelid retraction.
Area of Science:
- Ophthalmology
- Neuroscience
- Genetics
Background:
- Congenital ocular aberrant innervations involve cranial nerves like oculomotor, trigeminal, abducens, facial, and glossopharyngeal.
- Trochlear nerve involvement in congenital aberrant innervations is considered exceptionally rare or nonexistent.
Observation:
- A case study detailing an unusual presentation of congenital ocular aberrant innervation.
- The patient exhibited upper eyelid retraction specifically when attempting to move their eye within the superior oblique muscle's field of action.
Findings:
- The observed upper eyelid retraction indicates a primary synkinesis between the superior oblique and levator muscles.
- This suggests a novel form of aberrant innervation involving the trochlear nerve pathway.
Implications:
- This finding expands the known spectrum of congenital ocular aberrant innervations.
- Highlights the potential for trochlear nerve involvement in rare cases of synkinesis.
- Suggests a need for re-evaluation of diagnostic criteria for congenital cranial nerve palsies.
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