MoDi Twin

Summary

This study uses a new type of ultrasound technology for evaluation of blood vessels and flow of blood within the placenta. This new imaging technology will be performed in monochorionic [MoDi or MonoMono] twins, who share a placenta and may receive uneven shares of the placental blood flow or shunting of blood from one twin to the other. 

Development of this technology is needed to improve detection of and planning for treatment of pregnancies affected by twin-to-twin transfusion syndrome (TTTS) and other serious twin pregnancy complications. While the current study only enrolls eligible, healthy twins without TTTS or twin reversed arterial perfusion (TRAP), future studies may use this technology to create vascular maps of the placental in these affected TTTS/TRAP patients. The researchers believe that these vascular maps will allow clinicians to better target and correct improper blood vessel connections and uneven amounts of blood flow, greatly improving survival of both twins. 

The current study recruits healthy twins, gestational age 18 – 26 weeks, to demonstrate the ultrasound technology’s ability to create precise vascular maps of twin’s blood supply within the shared placenta and to evaluate normal placental structural and vascular connections.

Healthy patients with mono-di twin pregnancies who choose to participate in the current study receive a single, additional ultrasound scan utilizing ultrafast Doppler imaging. The scan will take around 10 – 15 minutes of additional time at the end of your regularly scheduled ultrasound appointment. The research’s ultrasound machine has been programmed to output the same strength of sound wave as a normal ultrasound machine would and so carries similar risks as receiving a routine ultrasound exam. Receiving a vascular scan of the placenta and its blood flow is free of charge for those participating in the research.

To be included in MoDi Twin, participants must be / have:

• Subject is 18 – 45 years of age at screening
• Non-anomalous, monochorionic, diamniotic (MoDi) or monochorionic, monoamniotic (MoMo) twin gestation without suspected genetic disorders
• Low-risk aneuploidy screening, if performed
• Intention to deliver at Carilion Roanoke Memorial Hospital (CRMH) or Carilion New River Valley Medical Center (CNRV)
• Anatomical survey has been performed
• 18 – 26 weeks gestational age
• Subject willing and able to provide/re-provide informed consent 

 To be included in MoDi Twin, participants must not be / have:

• Suspected fetal genetic disorder(s)
• Suspected fetal infection(s), twin-to-twin transfusion syndrome (TTTS), twin reversed arterial perfusion sequence (TRAPS), or maternal vascular disease
• Non-English reading and speaking
• Unstable housing or transportation
• Any other criterion which, in the clinical judgement of the investigator, would make the subject unsuitable for study enrollment

Keywords
Obstetrics; Maternal fetal medicine; Monochorionic twins; Healthy; Twins; Ultrasound; Placental imaging; Twin-to-twin transfusion syndrome; Twin reversed arterial perfusion; Doppler imaging