Bencze Syndrome

Autosomal dominant transmitted disorder with strabismus and hemifacial hyperplasia.

Hemifacial Hyperplasia with Strabismus.

Only a few cases have been described in the world literature, and the true incidence is unknown. Autosomal dominant inheritance is suspected.

Hemifacial hyperplasia involves the facial bones and facial soft tissue. Growth of the neurocranium is unaffected. The eyeball of the affected side is of normal size, but two of the three generations in the first described family had ipsilateral, uncorrectable amblyopia and/or convergent or alternating strabismus. Dentition was accelerated on the affected side. In the opinion of Bencze et al., hemifacial hyperplasia and eye features were genetically connected. In a second family that was described later, the phenotypic spectrum was expanded to include submucous cleft palate. Intelligence in this latter family reportedly was normal.

Although hemifacial hyperplasia is mild in many cases, involvement of the tongue, tonsils, and neck has been described in some cases. Severe respiratory distress can develop, similar to infants with extensive cystic hygroma. Therefore, a thorough clinical assessment of the upper airway is mandatory prior to anesthesia.

Other syndromes of hemifacial hyperplasia with or without bone involvement have been reported worldwide, first by Beck in 1836. However, these cases did not include eye features. In addition, syndromes of hemihypertrophy involving other body parts, such as Klippel-Trénaunay syndrome, are well known.