Marcus Gunn syndrome

Clinical presentation and management of congenital ptosis

Congenital ptosis is a rare condition characterized by lower positioning of the upper eyelid that is present at birth and is a clinical condition that is persistent if not treated. It may be unilateral or bilateral and may be associated with other ocular disorders or systemic conditions, including Marcus Gunn, Horner, and Duane syndromes. It is a benign condition but causes functional, cosmetic, and psychological problems in children. However, not all patients need to undergo surgery, and usually only patients at risk of amblyopia need a prompt surgical correction, while in other cases, surgery can be postponed. The grade of ptosis, the eyelid function, and the amblyopic risk are the parameters that affect the ophthalmologist’s decision on timing of surgery and the surgical technique to be used. In fact, there are several types of surgical techniques to correct a congenital ptosis, although very often more than one is needed to obtain an acceptable result. This paper reviews the causes of congenital ptosis and associated diseases. Particular emphasis is given to surgical management and different procedures available to correct the upper eyelid anomaly and avoid permanent damage to visual function.

The wrong end of the telescope: neuromuscular mimics of movement disorders (and vice versa)

The rapid advances in modern neurology have led to increased specialisation in clinical practice. Being an expert in a neurology subspecialty offers advantages for diagnosing and managing specific disorders. However, specialisation also risks tunnel vision: interpreting symptoms and signs within one's own framework of reference, while ignoring differential diagnostic options from other subspecialties. This is particularly relevant when the patient's presentation potentially belongs to different neurological subspecialties. We illustrate this challenge by highlighting a series of clinical features that partially overlap between two common subspecialties: movement disorders and neuromuscular disorders. An overlap in clinical presentation is not rare, and includes, for example, involuntary eyelid closure (which could be active eye closure due to blepharospasm, or ptosis due to weakness). Other overlapping features include abnormal postures, involuntary movements and gait changes. We describe two of these overlapping features in more detail and emphasise the possible consequences of 'looking through the wrong end of the telescope' in such patients, as this may lead to a wrong differential diagnosis, unnecessary investigations and a delayed treatment start.

"See-saw" Marcus Gunn syndrome

The authors report an unusual case of Marcus Gunn syndrome in an adult patient, characterized by classical Marcus Gunn on one side and inverse Marcus Gunn on the other side. The patient exhibited a "see-saw" kind of eyelid movement on opening and closing the mouth and on moving the jaw from side to side. This clinical entity has been reported very rarely. A similar but etiologically different acquired condition seen commonly in adults, Marin Amat syndrome, is also discussed.

Management of morderate-to-severe Marcus-Gunn syndrome by anastomosis of levator and frontal muscles

AIM

To study the effect of clinical management of moderate-to-severe Marcus-Gunn syndrome (MGS) by anastomosis of levator and frontal muscles.

METHODS

The medical records of 13 patients with moderate-to-severe MGS who underwent surgeries in our institute between 2000 and 2007 were reviewed retrospectively. They underwent unilateral anastomosis of levator and frontal muscles under local anesthesia.

RESULTS

Postoperative follow-up periods ranged from 6 to 36 months, with an average of 12 months. All eyelids (100%) showed complete resolution of jaw-winking, ten eyelids (76.9%) had good correction of ptosis, with equal plapebral apertures and symmetrical contours, three (23.1%) showed residual mild ptosis (<2mm).

CONCLUSION

For moderate-to-severe MGS, unilateral anastomosis of levator and frontal muscles provides satisfied correction of jaw-winking and ptosis.