Atypical Vasa Previa in a Velamentous Cord Insertion Identified During Sonographic Examination

Abstract

Vasa previa is a life-threatening complication of a velamentous cord insertion. Understanding variations of this condition is vital to ensuring optimal patient outcomes. The case presented is of a 27-year-old primigravida woman whose condition was diagnosed during her second-trimester obstetric sonographic examination. The case demonstrated an unusual variation of vasa previa, in which a single fetal vessel separated from the membranous insertion located near the fundal placenta and traversed posteriorly through the chorionic membrane to within 0.83 cm of the internal os. The case was followed with the most up-to-date standards recommended by the American Institute of Ultrasound in Medicine.

Prenatal diagnosis and postnatal outcome of Type‐III vasa previa: systematic review of literature

“…In addition to the two well-described categories of VP, a third phenotype was reported recently, characterized by aberrant vessels leaving the placental surface and subsequently returning to the placental mass with a 'boomerang orbit', in the absence of a velamentous cord insertion or a bilobed/succenturiate placenta (Figure 5) 9,10,29,30 . In view of our findings, we would like to challenge this definition of Type-III VP: the presence of a velamentous cord insertion or succenturiate lobes does not define per se VP Type I and Type II, respectively, since aberrant vessels of Type-III VP can coexist along with placental or cord abnormalities, as long as these structures are not adjacent to the internal os and the aberrant vessel represents the only vascular structure in the lower uterine segment 12,[24][25][26] .…”

Sonographic Detection of Placenta Percreta With Associated Placenta Previa and Succenturiate Lobe

“…11 While sonography is often the preferred single imaging modality for evaluating for PAS, the accuracy for diagnosing it remains higher when both sonography and MRI are conducted together (97.5%). 2,13…”

“…11 While sonography is often the preferred single imaging modality for evaluating for PAS, the accuracy for diagnosing it remains higher when both sonography and MRI are conducted together (97.5%). 2,13 It is important to note that sonography has technical limitations and user dependency leading to inaccuracies of diagnosing PAS. 2 It has been shown that second trimester sonographic findings associated with the misdiagnosis of PAS included abdominal fat, bladder fullness, and placental location.…”

“…2 Generally, lower frequency transducers (such as the C 5-1 MHz curvilinear transducer) are traditionally used for the sonographic imaging of deep structures, given this promotes deeper penetration but decreased resolution. 13 Linear transducers, however, are best used for imaging superficial structures given that resolution will be enhanced but that depth will be compromised. 13 Obstetric sonography typically utilizes lower frequency transducers due to the deep location of the fetus.…”

“…13 Linear transducers, however, are best used for imaging superficial structures given that resolution will be enhanced but that depth will be compromised. 13 Obstetric sonography typically utilizes lower frequency transducers due to the deep location of the fetus. 14 However, higher frequency transducers can be utilized in obstetric sonography for imaging superficial structures, like an anteriorly positioned placenta.…”