Ultrasound Flashcards
Triploidy pathogenesis and ultrasound finding
Complete extra set f chromosomes
69 XXY or 69 XXX
Two sperm or diploid egg
Lethal inutero
AFP 8x normal
USS: Severe IUGR Ventriculomegly Arnold chiari, holoprosencephaly agenesis corpus callosum Cystic hygroma Facial cleft Congenital heart disease Renal anomalies Omphalocole Meningocele
What are the Chiari malformations
Chiari malformations are a heterogeneous group of disorders that are defined by anatomic anomalies of the cerebellum, brainstem, and craniocervical junction, with downward displacement of the cerebellum, either alone or together with the lower medulla, into the spinal canal [1].
Chiari I malformation (CM-I) is characterized by abnormally shaped cerebellar tonsils that are displaced below the level of the foramen magnum (image 1).
●Chiari II malformation (CM-II), also known as Arnold-Chiari malformation, is characterized by downward displacement of the cerebellar vermis and tonsils, a brainstem malformation with beaked midbrain on neuroimaging, and a spinal myelomeningocele (image 2 and image 3 and figure 1).
●Chiari III malformation (CM-III) is rare and combines a small posterior fossa with a high cervical or occipital encephalocele, usually with displacement of cerebellar structures into the encephalocele, and often with inferior displacement of the brainstem into the spinal canal (image 4).
Trisomy 13 Epidemiology Prognosis Problems Uss findings
1/5000-10 000
AMA
Lethal
85% die in the first year
80% CHD ASD / VSD many more complex
Poly cystic kidneys
Omphalocoele
Holoprosencephaly Cleft lip Enlarged cisterna Magna Close eyes Cystic hygroma Nose absent / single nostril Hand and feet abn - clubbed, polydactyl CHD NTD IUGR
What is a Cystic hygroma
●Cystic hygroma is a congenital malformation resulting from lymph accumulation in the jugular lymphatic sacs due to obstruction of the lymphatic system in the fetal neck. Cystic hygromas may be septated or simple
Cystic hygromas are associated with an increased risk for fetal aneuploidy (particularly trisomy 21) and structural malformations (particularly congenital heart defects), both of which increase the risk for miscarriage, hydrops, fetal demise, and neonatal death
Trisomy 18
Epidemiology
Prognosis
Problems
1:3000 m1:f3 Lethal iugr Microdolicocephaly Micrognathia 80% CHD- complex polyvalvular Clenched hands Malformed limbs prominent occiput
