Initial clinical experience with a 48 by 48 element biplane transesophageal probe

Three-dimensional ultrasound experience in obstetrics

PURPOSE OF REVIEW

Three-dimensional (3D) ultrasound is a natural development of the imaging technology. Fast computers are essential to enable 3D and four-dimensional (4D) ultrasound pictures. A short review of the technical points and clinical aspects is presented. Our purpose is to acquaint the reader with the possibilities of this new technology and to increase awareness of its present clinical usefulness. A short review of technical information is provided.

RECENT FINDINGS

The advantages of 3D and 4D ultrasound in certain areas are unequivocal. Its use in the workup of fetal anomalies involving the face, limbs, thorax, spine and the central nervous system are already applied by most centers. The use of this technology in applying color Doppler, in guiding needles for different puncture procedures as well in evaluating the fetal heart are under close research scrutiny. The bonding effect between the parents and their future offspring is becoming evident as 3D ultrasound is used. Consulting specialists understand fetal pathology better and can better plan postnatal interventions. 4D or real time 3D ultrasound was developed and is expected to achieve new meaning with the planned introduction of electronic transducer multilinear arrays.

SUMMARY

3D ultrasound is an extremely promising imaging tool to image the fetus. In spite of the scant outcome studies the potential of 3D ultrasound is understood by a large number of obstetricians, maternal fetal specialists and imaging specialists.

Three-dimensional ultrasound imaging

The objective of this article is to provide scientists, engineers and clinicians with an up-to-date overview on the current state of development in the area of three-dimensional ultrasound (3-DUS) and to serve as a reference for individuals who wish to learn more about 3-DUS imaging. The sections will review the state of the art with respect to 3-DUS imaging, methods of data acquisition, analysis and display approaches. Clinical sections summarize patient research study results to date with discussion of applications by organ system. The basic algorithms and approaches to visualization of 3-D and 4-D ultrasound data are reviewed, including issues related to interactivity and user interfaces. The implications of recent developments for future ultrasound imaging/visualization systems are considered. Ultimately, an improved understanding of ultrasound data offered by 3-DUS may make it easier for primary care physicians to understand complex patient anatomy. Tertiary care physicians specializing in ultrasound can further enhance the quality of patient care by using high-speed networks to review volume ultrasound data at specialization centers. Access to volume data and expertise at specialization centers affords more sophisticated analysis and review, further augmenting patient diagnosis and treatment.

Three-dimensional fetal echocardiography

The complex anatomy and dynamics of the heart make it a challenging organ to image. The fetal heart is particularly difficult because it is located deep within the mother's abdomen and direct access to electrocardiographic information is difficult. Thus more complex imaging and analysis methods are necessary to obtain information regarding fetal cardiac anatomy and function. This information can be used for medical diagnosis, model development and theoretical validation. The objective of this article is to provide scientists and engineers with an overview of three-dimensional fetal echocardiography.

Pediatric biplane transesophageal echocardiography: preliminary experience

Recent development of prototype pediatric biplane transducers has extended the use of biplane TEE imaging to the neonate. One such TEE probe with 64 imaging elements in each pallet was used perioperatively in 46 infants and children (weight 2.9 to 32 kg) undergoing surgery for complex congenital heart disease. The success rate for passing the transducer, complications of the procedure, and the number of cases in which the vertical plane provided information that was not available from the horizontal plane were determined. Probe insertion was successful in all patients. Imaging was discontinued in one neonate because of possible airway compression by the probe. Image quality was excellent in the other 45 patients. The vertical plane added information over that obtained from the horizontal plane in 58 (44%) of the 132 anomalies identified. The addition of the vertical plane was especially useful in imaging abnormalities of the ventricular outflow tracts.