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OJHAS Vol. 8, Issue 1: (2009
Jan-Mar) |
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Marcus Gunn Jaw Winking Phenomenon -
A case of the widening eye |
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Kamalakshi G. Bhat,
Associate Professor,
Department of Pediatrics
Anupama Karanth,
Associate Professor,
Department of Ophthalmology
Kasturba Medical College,
Mangalore. |
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Address For Correspondence |
Associate Professor of
Paediatrics,
Kasturba Medical College
Hospital,
Attavar, Mangalore – 575 001
INDIA
E-mail:
bhat_kamalakshi@yahoo.co.in |
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Bhat KG, Karanth A. Marcus Gunn Jaw Winking Phenomenon -
A case of the widening eye. Online J Health Allied Scs.
2009;8(1):10 |
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Submitted: Mar 6, 2009; Accepted Apr
25, 2009; Published: May 5, 2009 |
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| Abstract: |
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Marcus
Gunn jaw winking phenomenon is a congenital synkinetic movement due
to synkinesis between the upper eyelid and the pterygoids and it accounts
for 8% of patients with congenital ptosis. In rare instances, ptosis
may be absent. We present a case of Marcus Gunn Jaw Winking phenomenon
without ptosis at presentation
Key Words: Congenital ptosis, Jaw winking phenomenon
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Synkinesis
is a simultaneous movement or a coordinated sequence of movement of
muscles supplied by different nerves or by peripheral branches of the
same nerve. Marcus Gunn jaw winking phenomenon is a congenital synkinetic
movement first reported by Marcus Gunn in 18831. Although
this synkinesis between the upper eyelid and the pterygoids is well
known, it accounts for only 8% of patients with congenital ptosis in
the paediatric practice2. In rare instances, ptosis itself
may be absent complicating the diagnosis.
A 6 month
old male infant was brought by his mother with complaints of widening
of one eye at different times of the day. There were no other ocular
or systemic complaints. The child was born full-term by vaginal delivery.
The neonatal period was uneventful. His growth and development were
appropriate for age. Systemic examination was normal. The ophthalmologist
conducted a detailed examination of the eyes. Fixation, gaze and following
movements were normal. Palpebral fissures appeared equal in both eyes.
There was no evidence of proptosis. However, on the mother's insistence,
patient was re-examined a week later and at this time widening of left
palpebral fissure was noted. An ophthalmologic evaluation revealed elevation of
left eyelid associated with movements of the mouth, especially chewing
and sucking (Fig. 1). There was no evidence of ptosis at this stage. Visual
development was appropriate for age. Rest of the ocular examination
was considered normal. A diagnosis of Marcus Gunn jaw winking phenomenon
was made in view of the synkinetic nature of the abnormality, in spite
of the absence of ptosis.
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Figure 1: Upshoot
of left upper eyelid on lateral movement of mouth. Note the absence
of ptosis at rest |
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Figure 2: Mild ptosis
apparent in the left eye at one year |
Patient
was again examined at one year of age. He was noted to have ptosis of
mild degree at this time (Fig. 2). Gaze, extra ocular movements and fixation
were normal. Retinoscopy was found to be within the normal range in
both eyes. The mother felt that the elevation of the eyelid was much
less and present only during yawning. Various movements of the mouth
were unable to induce eyelid elevation at this examination.
Marcus
Gunn jaw winking phenomenon is a well recognised synkinesis in congenital
ptosis. When the mouth is opened or jaw is moved laterally, the ptotic
eyelid elevates. This results from a congenital aberrant connection
between the trigeminal nerve controlling mastication and oculomotor
nerve supplying the levator palpebrae superioris. These movements are
not volitional and are termed as associated reflexes of misdirection.
The exact mechanism of these movements is not understood. It is thought
that an abnormal connection exists in the central nervous system between
the nerve supply of the two muscles1. In the fully developed
form of Marcus Gunn phenomenon, the upper eyelid covers varying portions
of upper cornea at rest, but when the jaw is opened, or moved laterally,
the apparently ptotic eyelid shoots upwards to a level higher than the
normal eye. The upshoot of eyelid occurs only on opening the mouth but
is not maintained if the mouth is kept open.
In our
patient, we were unable to see any up-shoot of the eyelid at the initial
examination. This was because the reflex is momentary and only follows
movements of the mouth including chewing, sucking or bottle-feeding.
While the synkinetic nature was apparent, initial examination showed
no ptosis. Six months later, ptosis was obvious. The degree of ptosis
can vary from none to mild (lid covering the cornea 2 mm more than the
normal 2 mm coverage) to moderate (3 mm) to severe (4 mm or more).
It can sometimes be absent3. The management generally depends
upon the amount of ptosis and the degree of jaw winking. In mild ptosis,
as in our patient, there may be no need for surgical intervention at
all. In case of moderate to severe ptosis, levator resection combined
with bilateral frontalis suspension maybe necessary4.
Detailed
ophthalmologic evaluation is necessary to detect associated abnormalities.
Ptosis does not affect vision directly unless
it is severe, but it can decrease vision by the association of anisometropia and astigmatism.
Uncorrected, these can lead to amblyopia.
If amblyopia is detected, aggressive treatment with occlusion therapy
and/or correction of anisometropia should be done prior to any surgical
correction for ptosis. Other associations include superior rectus palsy
and double elevator palsy which may need to be corrected before handling
the ptosis. Our patient exhibited no other associations. In view of
the later presentation of ptosis, patient still needs to be followed
up for development of amblyopia at a later stage.
Patients
generally feel that the upshoot of eyelid comes down with time, as was
felt by the mother of our patient. There has been no objective evidence
that synkinesis weakens with time. However, we were unable
to observe jaw winking at the last follow up.
This case
is presented to increase awareness of a rare condition and to highlight
that the diagnosis need not depend upon the presence of ptosis. The
synkinesis may not be apparent easily but needs to be brought on by
getting the child to do various movements of the mouth. Detailed ophthalmologic
evaluation is essential to rule out possible associations of anisometropia,
astigmatism in order to prevent amblyopia.
- Duke-Elder
S. Congenital anomalies of the ocular adnexa. In: Duke-Elder S, Editor.
System of ophthalmology. London: Henry Kimpton; 1964, Vol. 3, p900-905
- Lee V, Konrad
H, Bunce C, Nelson C, Collin JR. Aetiology and surgical treatment of
childhood blepharoptosis. Br J Ophthalmol 2002;86:1282-1286
- Kostick DA,
Bartley GB. Upper eyelid malpositions: Congenital Ptosis. In: Albert
DM, Jakobiec FA, editors. Principles and Practice of Ophthalmology:
Clinical Practice. Philadelphia: W.B. Saunders company; 1994. Vol. 4,
p 3466
- Khwarg SI,
Tarbet KJ, Dortzbach RK, Lucarelli MJ. Management of moderate to severe
Marcus Gunn jaw winking ptosis. Ophthalmology 1999;106:1191-1196
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