TY  - CHAP
M1  - Book, Section
TI  - Holoprosencephaly
A1  - Bianchi, Diana W.
A1  - Crombleholme, Timothy M.
A1  - D'Alton, Mary E.
A1  - Malone, Fergal D.
Y1  - 2015
N1  - 
T2  - Fetology: Diagnosis and Management of the Fetal Patient, 2e
AB  - Key  PointsA  complex  brain  malformation  characterized  by  the  forebrain  failing  to  cleave  into  two  hemispheres,  a  process  that  is  usually  completed  by  5  weeks.Four  subtypes  exist,  listed  in  order  of  decreasing  severity:  alobar,  semilobar,  lobar,  and  middle  hemispheric  variant.Incidence  is  approximately  1  in  8000  second  trimester  pregnancies.Approximately  40%  of  cases  have  a  chromosome  abnormality.  Of  these  75%  are  due  to  trisomy  13.Maternal  diabetes  increases  the  risk  of  holoprosencephaly  by  200-fold.Management  of  pregnancy  should  include  fetal  karyotype,  DNA  mutation  testing,  and  consideration  of  fetal  MRI.  A  detailed  family  history  should  be  obtained.Mutations  in  eight  different  genes  are  associated  with  holoprosencephaly  (SHH,  PTCH,  SIX3,  SL12,  ZIC2,  TGIF,  TDGF1,  and  FAST1).If  chromosome  abnormalities  and  craniofacial  anomalies  are  absent,  long-term  survival  is  possible.  
SN  - 
PB  - McGraw-Hill Education
CY  - New York, NY
Y2  - 2024/04/19
UR  - obgyn.mhmedical.com/content.aspx?aid=1106396444
ER  -