Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + At a Glance Download Section PDF Listen ++ Inherited developmental disorder characterized by pits of the lower lip and cleft lip or cleft palate. It is the most common cleft lip/palate syndrome. + Synonyms Download Section PDF Listen ++ Cleft Lip and/or Palate with Mucous Cysts of Lower Lip; Lip-Pit Syndrome; Lip-Pit-Cleft Syndrome. + History Download Section PDF Listen ++ Congenital genetic disorder first studied by A. Van der Woude in 1954. + Incidence Download Section PDF Listen ++ 1:70,000 live births. + Genetic Inheritance Download Section PDF Listen ++ Autosomal dominant. + Pathophysiology Download Section PDF Listen ++ Caused by mutations in the gene encoding interferon regulatory factor-6 located on 1q32-q41; allelic to popliteal pterygium syndrome. Clinical expression is highly variable from one individual to another. + Diagnosis Download Section PDF Listen ++ Clinically evocated in patients with cleft lip or palate and mucous cysts of lower lip. Lip-Pit Syndrome is the most common manifestation present in 90% of the affected. The cleft of lip and palate occur in 21%. + Clinical Aspects Download Section PDF Listen ++ Generally concerns only head with lower lip pits (corresponding to accessory salivary glands), cleft lip, cleft palate, cleft uvula, and hypodontia. + Precautions before Anesthesia Download Section PDF Listen ++ Evaluate the airway (clinical, radiographs) and teeth mobility. + Anesthetic Considerations Download Section PDF Listen ++ Direct laryngoscopy and tracheal intubation can be difficult because of cleft syndrome. Teeth lesions can occur more frequently. + Pharmacological Implications Download Section PDF Listen ++ Avoid muscle relaxants until confirmation that face-mask ventilation is possible or airway is secured. + References Download Section PDF Listen ++Guner U, Celik N, Ozek C, et al: Van der Woude syndrome. Scand J Plast Reconstr Surg Hand Surg 36(2):103, 2002. ++Ryns JP, Devriendt K: On the nosology of van der Woude syndrome and popliteal pterygium syndrome: Implications for genetic counseling. Genet Couns 11(1):59, 2000. ++van der Woude A: Fistula labii inferioris congenita and its association with cleft lip and palate. Am J Hum Genet 6:244, 1954.