Radiological Category Ultrasound Principal Modality 1 Ultrasound Principal

Radiological Category: Ultrasound Principal Modality (1): Ultrasound Principal Modality (2): None Case Report #0395 Submitted by: Nicolaus Wagner-Bartak, M. D. Faculty reviewer: Michael Redwine, M. D. Date accepted: 25 February 2007

Case History 21 -year-old woman, G 1 P 0 at 22 weeks and 4 days gestation presents for routine prenatal ultrasound. Her prenatal care and past medical history are unremarkable.

Radiological Presentations Transabdominal obstetrical ultrasound with color Doppler – Longitudinal view of fetal neck region

Radiological Presentations Transabdominal obstetrical ultrasound with color Doppler – Transverse view of fetal neck region

Test Your Diagnosis Which one of the following is your choice for the appropriate diagnosis? After your selection, go to next page. • Cord knots • Nuchal cord • Cord stricture

Findings and Differentials Findings: Longitudinal transabdominal sonographic images demonstrate a section of the umbilical cord between the fetal head and shoulders. Transverse sonographic images demonstrate a complete loop of umbilical cord around the fetal neck. The cord has normal arterial and venous color bloodflow. Differentials: • Nuchal cord with a single loop • Nuchal cord with multiple loops

Discussion A nuchal cord results from the wrapping of the umbilical cord around the fetal neck in utero. The presence of a nuchal cord is a common finding occurring in approximately 20 -25% of pregnancies. The presence of multiple coils of the umbilical cord around the neck is less frequent occurring in 2 in 1000 pregnancies [2, 3]. The presence of a single nuchal cord is associated with preterm delivery under 37 weeks and variable fetal heart rate decelerations but is not associated with any serious complications [1, 3]. No special management is required when a single nuchal cord is detected. Multiple nuchal cord with 4 or more loops can result in intermittent cord compression, significantly decreased birth weight and may require C-section if signs of fetal distress develop [3].

Diagnosis Nuchal cord with a single loop

References 1. Gonzalez-Quintero VH, Tolaymat L, Muller AC, et al: Outcomes of pregnancies with sonographically detected nuchal cords remote from delivery. Ob Gyn Surv, 2004 July; 59(7): 499 -500. 2. http: //www. emedicine. com/med/topic 3276. htm “Umbilical Cord Complications, ” accessed February 20, 2007. 3. http: //www. thefetus. net/page. php? id=172 “Ultrasound diagnosis of quintuple nuchal cord entanglement and fetal stress, ” accessed February 20, 2007.