Structured Training for Fetal Diagnostic Skills in a Maternal-Fetal Medicine Fellowship

Objective  The American Institute of Ultrasound in Medicine has described what constitutes a detailed fetal anatomic examination but what comprises an appropriate physician training program has not been described. The purpose of this paper is to describe a highly-structured program developed by our center to train maternal-fetal medicine fellows in a systematic approach to fetal diagnostic imaging. Study Design  We describe this approach in three phases. Phase I: Development of Skills as a Perinatal Sonographer, Phase II: Mentored Evolution to a Perinatal Sonologist and Phase III: Supervised Independent Practice as Consultant-in-training. Results  This curriculum was implemented in 2006. Of the eight maternal-fetal medicine fellows who completed this program, 100% were capable of following this curriculum and 100% felt comfortable performing and interpreting detailed sonograms including sonograms with significant and uncommon anomalies. Qualitative feedback was also positive. Finally, this structured approach resulted in an increase in the average total number of sonograms interpreted. Conclusion  Our curriculum, by following the explicit guidelines and expectations set out by the American Institute of Ultrasound in Medicine and the American Board of Obstetrics and Gynecology for practicing maternal-fetal medicine fellowship graduates, provides an opportunity to explore national standardization for this component of training.

Foetal premature atrial contractions during the second and third trimester are not associated with foetal breathing

Foetal premature atrial contractions (PACs) are the most commonly encountered and also the most benign foetal arrhythmia. A retrospective cohort study was conducted with the objective to assess whether the presence of foetal breathing was associated with the presence of foetal PACs. A further objective was to evaluate whether this association would affect neonatal outcomes at a high volume referral centre. The diagnosis of PACs was based on the observation of a premature atrial contraction followed by a ventricular contraction on ultrasound myocardial M-mode. Trained ultrasonographers documented in the ultrasound report whether or not foetal breathing was present with PACs. 91 exams were identified, which included 75 individual pregnancies. Six women were identified who had foetal PACs associated with foetal breathing on ultrasound evaluation. Foetuses with PACs did not differ between the associated breathing and no-associated breathing groups with respect to maternal age, parity, mode of delivery, gestational age at delivery or birthweight. This study reaffirms that isolated PACs are a benign finding. Furthermore, it adds to the pool of literature on foetal PACs in that it is not associated with abnormal pregnancy outcomes regardless of the presence or absence of foetal breathing. Impact statement • What is already known on this subjectSince foetal breathing can effect Doppler ultrasound assessment of the foetal cardiovascular system, it is reasonable to consider that it may impact conditions such as foetal arrhythmias. • What the results of this study addFoetal breathing does not impact on the presence of premature atrial contractions. • What the implications are of these findings for clinical practice and/or further researchFoetal breathing is not associated with the finding of foetal premature atrial contractions.

A transcervical chorionic villus sampling model for teaching

We sought to create a transcervical chorionic villus sampling model for teaching that would mimic a lifelike model. A model was created using silicone resembling the maternal interface. A cervix with an endocervical canal able to accommodate a catheter and a vagina was also created. Tap water was used as the amniotic fluid. Chorionic villus sampling was accomplished using this model with the actual ultrasound machines and environment as in the real model. This simulator allowed placental placement in different locations to increase the difficulty level as well as angulations and catheter handling. Given the low cost (less than $200), this model could be used indefinitely in a relaxed and controlled environment.

Prenatal diagnosis of Chiari malformation with syringomyelia in the second trimester

Routine anatomic ultrasound performed in the second trimester has a detection rate of approximately 70-90% for fetal congenital abnormalities (Nyberg and Souter, J Ultrasound Med 2001;6:655-674). The central nervous system abnormalities are one of the most common ones detected. Chiari malformation is among the CNS abnormalities diagnosed in the fetal period (Bianchi et al., Fetology - diagnosis and management of the fetal patient, McGraw-Hill, 2000). The Arnold-Chiari malformation was first described in 1883 by Cleland (Romero et al., Prenatal diagnosis of congenital anomalies, Appleton and Lange, 1988). It is characterised by the prolapse of the hindbrain structures below the level of the foramen magnum. It can be associated with skeletal abnormalities and neurological dysfunction. In type I, a lip of cerebellum is downwardly displaced with the tonsils, but the fourth ventricle remains in the posterior fossa. This condition may coexist with syringomyelia, which is a cyst formation on the cervical portion of the spinal cord (Creasy et al., Maternal fetal medicine principles and practice, 2004). We present a case where Chiari type 1 and syringomyelia detected at 18 weeks of gestation. The reason for referral to our center was an abnormal inward posturing of both upper and lower extremities (minimal gross movement and almost inexistent range of motion on fetal joints). On further fetal evaluation, an abnormal brain ultrasound was identified. Prenatal diagnosis of Chiari type 1 malformation and syringomyelia is almost nonexistent when reviewing the literature is the reason why this case is presented.

Reversible fetal hydrops associated with indomethacin use

BACKGROUND

Ductus arteriosus constriction is a known complication of exposure to indomethacin in utero. Nonimmune hydrops associated with indomethacin use has been reported in only six cases, all twins over 32 weeks' gestation.

CASE

We present a case of fetal hydrops associated with tricuspid regurgitation and ductal constriction developing within 30 hours of instituting indomethacin tocolysis in a 28-week singleton gestation. Discontinuation of indomethacin resulted in partial resolution of these findings 72 hours later. A normal infant was delivered subsequently.

CONCLUSION

Ultrasonographic screening for signs of constriction of the ductus arteriosus should be done within 48 hours of instituting indomethacin therapy at any gestational age.