Bencze Syndrome

At a glance

Inherited disorder with strabismus and hemifacial hyperplasia.

Synonyms

Hemifacial Hyperplasia with Strabismus; Oculofacial Syndrome.

Incidence

Only a few cases have been described in the world literature, thus the true incidence is unknown.

Genetic inheritance

Autosomal dominant inheritance is suspected.

Clinical aspects

Hemifacial hyperplasia involves the facial bones and soft tissues in the area of the zygomatic bone and mandibular angle but not the alveolar processes and the teeth. Growth of the neurocranium is unaffected. The eye on the affected side as well as the orbital diameter were of normal size, but two of the three generations in the first described family had ipsilateral, uncorrectable amblyopia, hypermetropia, and/or convergent or alternating strabismus. Dentition was accelerated on the affected side with unilaterally increased teeth size and advanced teeth age, which is considered indicative of lesion originating in early embryonic age. In the opinion of Bencze et al, hemifacial hyperplasia and eye features shared the same genetic basis. With the exception of one patient in a second family described, intelligence in this latter family reportedly was normal. (Bencze et al did not elaborate on the mental status of their patients.) That same patient was also of short stature (postnatal growth deficiency), had mild thoracolumbar scoliosis, pectus carinatum, coxae valgae, narrow iliac wings, hyperextensible knees, and a submucous cleft palate (the other family members were of normal height, had no other skeletal anomalies other than the facial hemihyperplasia and eye anomalies were limited to the hemihyperplastic side). Telecanthus and mild upslanting of the palpebral fissure on the affected side have been described in some patients.

Precautions before anesthesia

The hemifacial hyperplasia in this syndrome is mild. However, case reports of other types of facial hemihyperplasia with involvement of the tongue and tonsils resulting in severe respiratory distress have been described. Therefore, a thorough clinical assessment of the upper airway is mandatory prior to anesthesia.

Anesthetic considerations

Since the facial hemihyperplasia is generally mild, no specific anesthetic implications are expected.

Pharmacological implications

None specific to this syndrome.

Other conditions to be considered

Other syndromes of hemifacial hyperplasia with or without bone involvement have been reported worldwide already in the 19th century. 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.

References