Handbook of Genetic Counseling/Craniosynostosis-2

Craniosynostosis Introduction Myself, GC, Doc What have you been told in the past? Contracting Medical History Family History Physical exam Answer any questions you have Medical History/Pregnancy history Progress since the surgery Breathing difficulties when he was younger?/ Now? Did he require a trach? How's his feeding before? / Now? What does he currently eat? / How much? How was the delivery? / vaginal? When did you first suspect something was different? Family History Any people with funny shaped heads? Basics : birth defects, cancer at an early age, MR, miscarriages, etc. Craniosynostosis Definition Premature closure of the cranial sutures (joints between the bones of the skull) The severity and type depend upon which of the four sutures fuse together too early: sagittal, coronal, metopic, or lambdoid. The shape of the head is dependent upon which of the sutures is closed early. Six disorders called the FGFR-related craniosynostosis - most are related to those coronal craniosynostosis, NOT SAGITTAL!!!!! (probably do not apply in this case) Incidence Overall = 1/2000 - 1/2500 live births Characteristics of the FGFR-related ones Normal intelligence in many cases/DD and MR in others Hypertelorism Midface hypoplasia Small beaked nose Prognathism High arched palate Choanal atresia or stenosis Fusion of fingers or toes Genetics Autosomal dominant for the FGFR related (fibroblast growth factor receptors) Sporadic in most cases A mutation in the FGFR3 gene which is responsible for keeping things from getting too long (inhibits growth usually). When mutated, it seems to be over expressed = failure of things to grow completely causing early fusion of the skull and fingers/toes. Recurrence risks (empirical -isolated cases) Risk to siblings with two unaffected parents = coronal 5% Risk to siblings with two unaffected parents = sagittal 1% Sagittal synostosis Definition: when the sagittal suture fuses prematurely. It runs from the front of the head to the back and creates a boat-like head because the front and back of the skull bulge outwards to allow the brain to grow. Surgery repairs it by removing the sutures and widening the skull by opening both the lambdoid and coronal sutures on either side. Bone grafts may be placed inside to keep the skull wide enough. The most common of the craniosynostoses = 1/5250 incidence Typically isolated conditions/ not related to a syndrome. Resources National Organization for Rare Disorders PO Box 8923 New Fairfield, CT 06812-1783 800 999-6673 www.rarediseases.org March of Dimes Birth Defects Foundation 1275 Mamaroneck Avenue White Plains, NY 10605 800 MODIMES (663-4637) www.modimes.org ARC of the United States 300 East Border Street Suite 300 Arlington, TX 76010 (817) 261-6003 Craniosupport.com A parent organization on the web who have information and resources for people with all types of craniosynostosis and related syndromes before and after surgery. http://web.archive.org/20000708013217/members.aol.com/craniosupport/support.html Notes The information in this outline was last updated in 2000.