Three-dimensional ultrasonography in prenatal diagnosis

Abstract

Within the past five years, 3D ultrasonography has developed to the degree that it offers both the patient and the examiner an entirely new visual experience in prenatal diagnosis. With the system described here (Kretz-technik, Austria), any desired plane can be displayed within the stored volume, and within seconds a high-quality 3D surface or transparent image can be calculated and displayed on the ultrasound monitor without need for an external workstation. All of this can be performed routinely in the clinical setting. Since 1989 we have routinely examined a total of 458 fetuses (242 normal and 216 with anomalies) between 16 and 38 weeks of gestation, supplementing our conventional 2D ultrasound scans with a 3D examination using an abdominal volume transducer. A comparison of the 2D and 3D techniques shows that 3D provides a diagnostic gain in a large percentage of cases (64.2%). The simplest 3D technique of the orthogonal image display provided a diagnostic gain in 46.2% (61/132) of the cases owing to the accurate topographic depiction of the desired image plane. The combined 3D display (orthogonal format plus a 3D surface or transparent view) provided a diagnostic gain in 71.5% (233/326) of the cases. This higher percentage resulted from the additional 3D surface reconstruction, the ability to view and evaluate the fetus from various angles, the ability to determine the exact size of a fetal defect, the depiction of skeletal anatomy in the transparent mode, and the improved delineation of complex malformations. Problems with 3D imaging are encountered in patients with pronounced oligohydramnios, which prevents surface reconstruction, and in the examination of moving objects, which produce motion artifacts.

Reliability and validity of three‐dimensional fetal brain volumes.

“…Platt et al 16 reported that 3D ultrasonography confirmed the 2D diagnosis 91% of the time and enhanced or altered the diagnosis in 9% of cases. Another study by Merz et al 17 showed that just adding the simple 3D orthogonal image provided a diagnostic gain of 46.2%, and the combined 3D display provided a diagnostic gain of 71.5%. Kelly et al 18 concluded that 3D ultrasonography of the fetus allows complete anatomic study and visualization of detail that is difficult to perceive on conventional 2D scans.…”

Three‐dimensional ultrasonographic assessment of fetal hands and feet

“…With conventional two-dimensional ultrasonography, the assessment of overall structural detail of the fetal hands is often difficult and time-consuming 3 . Three-dimensional ultrasonography allows visualization of fetal malformations in all three dimensions at the same time, providing an improved overview and a more clearly defined demonstration of different anatomical planes, and might be suitable for evaluating complex fetal structures 4,5 . The objective of the current study was systematically to examine the fetal hands and feet by three-dimensional ultrasonography using a specially developed abdominal three-dimensional transducer.…”

Volume Measurement in Sequential Freehand 3-D Ultrasound

“…There have been several reviews of foetal applications of 3D ultrasound [121,156,173]. Much of this work has been concerned with the detection of foetal abnormalities [10], for instance cleft lip or other malformations of the face [107].…”

“…This is generally achieved by attaching the transducer to a stepper motor, for linear [92,104,117,169], rotational [51,91,136], fan [20,69] or intravascular linear [102] scanning. This kind of approach has also been used in integrated transducers, for instance Kretz Technik's 4 Combison 330 [1,2] and 530 [30,107,121,173], which scans an entire pyramidal volume. Diagnostic Ultrasound Corporation also produce an integrated scanner and volume calculation device, Bladderscan 5 , specifically for urological use [118].…”