Strabismus - Fundamentals of Clinical Ophthalmology.pdf

STRABISMUS
(a)
(a)
(b)
(b)
Figure 4.17 Developmentally determined aberrant
innervation resulting in the Marcus Gunn jaw winking
syndrome
(c)
Figure 4.16
nerve palsy
Child (a–c) with left ptosis due to third
tumour of nasopharynx, trauma, infections,
(Gradenigo syndrome), and vascular
malformation.
Benign sixth nerve palsy of childhood can also
occur in infancy when associated with febrile
illness. It is transitory and recovers within
weeks. 17–19 It is important to distinguish benign
sixth nerve palsy from pontine glioma if it does
not resolve within 6 weeks.
Third nerve palsy
This condition may be congenital. The palsy
is usually unilateral but less commonly bilateral.
The pupil may be spared and the condition may
be associated with aberrant regeneration. Third
nerve palsy is associated with ophthalmoplegic
migraine in adolescent and early adult life as well
as with posterior cerebral artery aneurysms or
vascular malformations. Traumatic causes
include uncal herniation in severe head
trauma. 20,21,22
Recovery may be associated with aberrant
regeneration and paradoxical movements
(Figure 4.16). Another common developmental
aberrant regeneration involves the miswiring
between motor fifth nerve and eyelid movement
from seventh nerve innervations of the
orbicularis. It results in the jaw winking
phenomenon (Figure 4.17).
Superior oblique paresis
Superior oblique paresis is relatively common
in childhood (Figure 4.18). The weakness may
be a true fourth nerve palsy but a significant
number are due to developmental anomalies of
the superior oblique muscle, particularly its
tendon. The child usually presents later in
infancy with a compensatory torticollis. There
may be inferior oblique overaction and a positive
Bielschowsky head tilt test (Figure 4.19).
Approximately one quarter of superior oblique
palsies are congenital. Some cases of apparent
congenital fourth nerve palsy have been
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