There was enhancement and thickening of the left inferior oblique
muscle measuring 8.
They innervate superior rectus, inferior rectus, medial rectus and inferior oblique
muscle, and levator palpebrae muscle.
A 15-year old boy presented with features characteristic of FND type I caused by ALX3 gene mutation, after the correction of severe hypertelorism, median nasal cleft with a broad nasal root and associated de-compensated intermittent exotropia with overaction of the inferior oblique
muscles with V pattern.
Table 1: Extraocular examination of left eye Extraocular muscle Function Movement of left eye Medial rectus Adduction Absent Superior rectus Elevator in abduction Absent Inferior rectus Depressor in abduction Absent Inferior oblique
Elevator in adduction Absent Superior oblique Depressor in adduction Present but not full Lateral rectus Abduction Absent
The first surgical approaches for the inferior oblique
(IO) muscle date back to the mid 19th century.
Elevation defective in upgaze both in abduction and adduction (revealing right superior rectus and right inferior oblique
Cranial nerve III (CN III) innervates the superior, inferior, medial recti and the inferior oblique
Mechanical entrapment of the orbital content most commonly the inferior rectus muscle followed by the inferior oblique
muscle causes diplopia in up gaze and down gaze and the forced duction test in this case is positive.
Erosions were noted in the right inferior orbital wall and the disease was noted to involve the inferior oblique
and medial rectus muscles, pushing right optic nerve superiorly.
While the levator palpebrae superioris and superior rectus muscles were innervated by the upper branch, the medial rectus, the inferior rectus, and the inferior oblique
muscles were innervated by the lower branch (2-4).
Soft tissue palpation revealed tight and tender sternocleidomastoid (SCM), upper trapezius, levator scapula, superior and inferior oblique
, rectus capitis minor, lateral pterygoids and masseter muscles bilaterally.
The medial and lateral recti move the visual axis from side to side; the superior and inferior recti move the axis up and down and the superior and inferior oblique
roll the eyeball around visual axis.