Novel Methods Available to Treat Treacher Collins Syndrome in Children

By the time a child with Treacher Collins Syndrome (TCS) reaches the age of 18, he or she has had dozens of surgeries.

TCS, also called mandibulofacial dysostosis and Franceschetti-Klein Syndrome, is a genetic condition involving underdevelopment of the structures of the head and face. It occurs in at least one in every 10,000 live births. The physical characteristics vary enormously in severity from one child to the next. But certain abnormalities of the head, face and craniofacial areas are characteristic. These children commonly have down-slanting eyes, notched lower eyelids, no lower jaw or one that is small and slanting, as well as malformed ears, and an underdevelopment or absence of cheekbones.

These children may undergo surgeries to correct hearing, a possible cleft palate, repairs of the eye socket, cheekbones, eyelid notches, ear reconstruction, and chin and jaw correction. Most of these children have normal development and intelligence. Experts say they benefit most from early intervention speech and language programs.

Dr. John Teichgraeber, a plastic surgeon in The University of Texas-Houston Medical School's division of pediatric surgery, works with Dr. Jaime Gateno, a dentist and dental researcher at the UT-Houston Dental Branch. Dr. Gateno has refined the concept of linear, transverse and angular distraction correction for kids with TCS. The multiplanar mandibular distractor that they use is a computer-based modeling program that simulates the movements and calculates the vectors of the active jaw.

"We've been using this technique for three or four years. It's been relatively successful," says Dr. Teichgraeber. "You see that jaw? Almost perfect." He then explains that a child's CAT scan results are fed into the computer, and then a device is designed at the workstation that fits the child's dimensions. He says that the virtual reality simulation program allows his team minute design control, based on exquisite mathematical calculations.

TCS is believed to be caused by a change in the gene on chromosome 5, which affects facial development. Geneticists can now determine whether the condition is a new mutation or one that has been passed on. Oftentimes Treacher Collins Syndrome is inherited from a parent. There is a 50 percent chance of passing it on, if you are a parent with TCS. However, experts say only 40 percent of TCS cases are attributable to inheritance. The other 60 percent are an anomaly. There's no family history of the condition. These particular cases seem to occur sporadically in the very early stages of fetal development.

When children with TCS are born, they can have breathing or eating difficulties. Their eyes have a tendency to dry out, leading to infection. They can have cleft palate or abnormally small or absent thumbs. Often they experience a 40 percent hearing loss, as well.

Osteodistraction, or bone expansion, is a common corrective measure for these children. It has a long history. In 1905, a scientist by the name of Codivilla first described the concept of bone lengthening, and in 1927, the tibia was lengthened with a compressed spring. However, there was a high incidence of complication and the techniques were not widely accepted.

(To be continued in the July 15, 2000 Issue)

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©2006 Texas Medical Center

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