title: Sonographic visualization of the middle phalanx of the fetal fifth digit between 13 and 17 weeks of gestation.
abstract: OBJECTIVE
  To assess in utero visualization of the middle phalanx of the fifth digit (MPFD) between 13 and 17 weeks of gestation.
  
  
  METHODS
  This was a prospective cross-sectional study in which women attending for fetal sonographic examination between 13 + 0 and 17 + 6 weeks of gestation were evaluated for the presence of the middle phalanx of the fifth digit (MPFD). A total of 682 fetuses with normal findings on first-trimester anatomical examination were recruited. Using transvaginal multifrequency 4-8 and 5-9 MHz probes, the fifth finger was examined in both axial and lateral views until optimal visualization of the MPFD was achieved.
  
  
  RESULTS
  The MPFD was visualized in 14.3% (2/14) of cases at 13 weeks, 70.3% (154/219) at 14 weeks, 82.2% (240/292) at 15 weeks, 97.4% (111/114) at 16 weeks and 100% (43/43) at 17 weeks of gestation.
  
  
  CONCLUSIONS
  Ultrasound visualization of the MPFD gradually increases during the 13- to 17-week period. This emphasizes the limited role of non-ossification of the MPFD as a sonographic marker of Down syndrome before 17 weeks of gestation.
authors: Department of Obstetrics and Gynecology, Chaim Sheba Medical Center, Tel-Hashomer, Sackler School of Medicine, Tel-Aviv University, Israel. zalel_y@netvision.net.il
authors: Y
authors: Y
authors: Zalel
authors: R
authors: R
authors: Achiron
authors: Z
authors: Z
authors: Kivilevitch
mesh_terms: D003430:Cross-Sectional Studies; D004314:Down Syndrome / Q000000981:diagnostic imaging*; D005260:Female; D005315:Fetal Diseases / Q000000981:diagnostic imaging*; D050278:Finger Phalanges / Q000000981:diagnostic imaging* / Q000196:embryology; D005865:Gestational Age; D006801:Humans; D010012:Osteogenesis; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D016216:Ultrasonography, Prenatal / Q000379:methods