hello everybody our lecture today about ultrasound of fetal skeleton anomalies 1. skeletal dysplasia approach to prenatal diagnosis there is a wide range of rare skeletal diplagias each with a specific recurrence risk dysmorphic expression and implications for neonatal survival and quality of life the incidental discovery of a skeletal dysplasia on routine ultrasound screening in a pregnancy not known to be at risk of a specific syndrome necessitates a systematic examination of the limbs head thorax and spine to arrive at the correct diagnosis 2. achondrogenesis ultrasound diagnosis severe shortening of the limbs narrow thorax short trunk length and large head associated with micronathia nuchal edema and polyhydramnios there are two types of achondrogenesis type i 20 autosomal recessive there is poor mineralization of the skull and vertebral bodies as well as rib fractures type 2 80 sporadic there is poor mineralization of the vertebral bodies but not the skull and there are no rib fractures 3. achondroplasia ultrasound diagnosis short limbs short hands and fingers large head with frontal bossing and depressed nasal bridge and lumbar scoliosis limb shortening and typical facial features become apparent greater than 22 weeks gestation [Music] 4. asphyxiating thoracic dystrophy ultrasound diagnosis phenotypic expression varies characteristic features are short narrow chest with short ribs and mild to moderate rhizomelic femur and humerus limb shortening which may become apparent greater than 22 weeks gestation the condition is also referred to as june syndrome 5. adolosteogenesis ultrasound diagnosis severe shortening of the limbs narrow thorax club feet dislocations of the hips knees and elbows associated with prominent forehead hypertelorism micronathia and cleft palate and hitchhiker thumbs the features are similar but more severe to those of diastrophic dysplasia [Music] 6. campomelic dysplasia ultrasound diagnosis shortening and bowing of the long bones of the legs bilateral acute femoral angulation narrow chest hypoplastic scapulas large cavarium with disproportionately small face microanathia 7. craniosynostosis ultrasound diagnosis premature fusion of cranial sutures resulting in abnormal shapes of the cranium eight diastrophic dysplasia ultrasound diagnosis phenotypic expression varies characteristic features include severe shortening and bowing of all long bones multiple joint flexion contractures and scoliosis club feet and abducted position of the thumbs referred to as hitchhiker thumb 9. ellis von crayfeld syndrome ultrasound diagnosis acromalic and mesomalic shortness of limbs postaxial polydactyly narrow chest ectodermal dysplasia and heart defects 10. hypophosphatasia ultrasound diagnosis in the prebatal type there is severe micromelea severe thoracic hypoplasia diffuse hypomineralization decreased echogenicity involving all the bones except for clavicles 11. yarcolovin syndrome ultrasound diagnosis fusion of several vertebral bodies and misalignment with the ribs which are also fused at the part nearest the spine the trunk is short but the arms and legs are of normal length 12. osteogenesis imperfecta ultrasound diagnosis spectrum of the defects characterized by fragile bones there are at least eight recognized forms of osteogenesis imperfecta designated type i through type 8 with overlapping characteristic features type i is the mildest form and type 2 is the most severe signs and symptoms of the other types fall somewhere between these two extremes most cases that present prenatally are types 2 and 3 type i fragile bones blue scleri and progressive deafness ultrasonography in the second and third trimesters may demonstrate fractures of long bones type 2 short limbs and ribs with multiple fractures hypomineralization of the skull type 3 multiple fractures usually present at birth resulting in scoliosis and very short stature 13. short rib polydactyly syndrome ultrasound diagnosis micromelea short ribs with hypoplastic thorax polydactyly usually pre-axial there are four types of short-rib polydactyly syndrome type i saudinonun narrow metaphysis type 2 myevsky facial cleft and disproportionately shortened tbi type 3 name off white metaphyses with spurs type 4 beamer langer median cleft lip and ambiguous genitalia in some 46 zy individuals [Music] 14. thinataphoric dysplasia ultrasound diagnosis severe shortening of the limbs narrow thorax normal trunk length and large head with prominent forehead there are two types of phenatophoric dysplasia type i more common sporadic the femurs are curved telephone receiver type 2 rare sporadic the femurs are straight but the skull is cloverleaf-shaped [Music] you