Advanced Topics on Three-Dimensional Ultrasound in Obstetrics and Gynecology

Edward Araujo

• Publisher: Bentham Science Publishers
• Year: 2016
• Print ISBN: 9781681082103
• eBook ISBN: 9781681082097
• Topic: Medicine
• Subtopic: Gynecology, Obstetrics & Midwifery

Advanced Topics on Three-Dimensional Ultrasound in Obstetrics and Gynecology is a comprehensive and handy guide for sonographers, obstetricians, gynecology and radiology professionals, and all technicians working in ultrasound laboratories who are interested in taking advantage of all the resources provided by this imaging technique. The book is divided in three sections which give information on a variety of relevant topics: Three-Dimensional Ultrasound Instrumentation and Technology. This section explains different ultrasound methods that can be used for three-dimensional imaging. It is complemented by a discussion on how to use the techniques in telemedicine.
The Use of Three-Dimensional Ultrasound During Pregnancy. This section explains the methods used to assess fetal organs, behavior and defects during different stages of pregnancy.
The Use of Three-Dimensional Ultrasound When Evaluating Female Reproductive Physiology. This section covers diagnostic procedures for ovarian and uterine abnormalities and neoplasms.

The Assessment of Fetal Neurobehavior with Four-dimensional Ultrasound

Introduction

In utero behavior of the fetus is assessed with the assistance of ultrasound technology, through direct observation in utero of real time movements and activities of the fetus [1 - 3]. Advances of ultrasonographic machines especially the better depiction with explicit details of three-dimensional (3D) and four-dimensional (4D) real time images, have given the opportunity to study in real

time and with explicit detail fetal anatomy and fetal activity. Studies have shown that there is a specific fetal behavioral pattern that corresponds to each week or trimester of in utero life and this behavioral pattern reflects the process of human brain development and maturation [4]. The anatomic and functional development of the human brain is a uniquely complex and long lasting procedure that goes through strictly structured developmental stages, which start from the second month of gestational age and continue up to adult life [4].

Maturation and evolvement of cerebral anatomy function is a very long process that is affected by many genetic and epigenetic factors, and its completion continues for many years after birth. The most important steps of human brain development are shown in Table 1. Human brain development is a very structured and detailed procedure, but as such it is at the same time very sensitive and susceptible to a wide variety of factors and defects, that may occur during any of the phases of intrauterine life. In cases of extremely premature neonates the brain development ex utero, no matter how much intensive neonatal units have progressed cannot mimic the environment and the development that the brain should have in utero, even when the postnatal environment and feeding mimics the conditions of in utero life [5, 6]. Genetic factors, external stimuli, pathological conditions or even environmental changes, can affect the fetal human brain up to a degree that may be difficult to assess, especially prenatally. In many cases we are unable to detect fetal brain impairment, and even when we suspect it, again we are often unable to say in what way and to what extent will the fetus be affected.

We are not certain when an insult to the human brain can happen whether it occurs during in utero life, during labor or sometime after birth. What is more even if we identify a brain injury we cannot be certain how will it affect this fetus/neonate, as it may present with a wide variety of clinical pictures, ranging from mild motility or learning difficulties to the most severe form which is cerebral palsy(CP) [4]. Indeed, neurological disability is one of the most feared complications in perinatal medicine and its diagnosis antenatally is one of the greatest challenges in obstetrics. What is more, the cause and effect relationship of neurological disabilities is often uncertain. A method that would be able to assess the functional part of the fetal nervous system that is the fetal behavior would be an extremely useful tool in the hands of perinatal medicine that would answer many questions [6, 7]. Assessment of fetal behavior is time consuming, but only when normal behavior is well understood and documented, will be possible to compare it with abnormal cases, detect the differences between them, and as a result identify and perceive abnormal behavior before birth.

Table 1 Major events in neural development [4].

Developmental event	Peak time of occurrence
• Primary neurulation (Dorsal Induction)	3-4 weeks antenatally
• Prosencephalic cleavage (Ventral Induction)	5-6 weeks antenatally
• Neuronal Proliferation
Cerebral	2-4 months antenatally
Cerebellar	2-10 months postnatally
• Neuronal Migration
Cerebral	3-5 months antenatally
Cerebellar	4-10 months antenatally
• Neuronal Differentiation
Axon outgrowth	3 months - birth
Dendric growth & Synapse formation	6 months - 1 year postnatally
• Synaptic rearrangement	Birth - years postnatally
• Myelination	Birth - years postnatally

Ultrasound for the assessment of fetal behavior

The cerebral growth and maturation of a fetus appears to be represented by its behavior in utero [8, 9], while studies have shown that their movements are very good indicators of neurobehavioral organization and of the future neurological integrity of the fetus [10 - 17]. Two-dimensional (2D) ultrasound allowed up to a point the complete evaluation of the fetal anatomy and gave the opportunity to view fetal movements. One the pioneering studies about the importance of fetal movements, was published more than 3 decades ago offering the first knowledge in this new field of fetal medicine and at the same time the inspiration to study the fetal behavior as a whole in utero [18]. De Vries et al. followed and analyzed the qualitative and quantitative aspects of giving more details on the movements and a more methological way of studying them [19 - 21]. It has been suggested that distinguishing between types of fetal movements and behavior according to each trimester could help to dissever routine-normal fetal behavioral patterns, from possible pathological patterns [21 - 24]. The method that brought a revolution to fetal real time imaging was 4D ultrasonography which offered a more objective and accurate way than 2D ultrasound [24 - 27]. 3D/4D ultrasound has now become routine in clinical practice and fetal assessment offering better pictures than 2D ultrasound and allowing observation of fetal movements, even detailed ones such as fingers and facial movements [28, 29]. The long term study of fetuses with 4D ultrasound allowed the production of measurable units that could be finally applied systematically for the assessment of fetal behavior [30]. One of the greatest advantages of 4D ultrasound compared to 2D is the detailed pictures of the fetal face (e.g. smiling, crying, mouthing and blinking), something that cannot be achieved with 2D ultrasound.

There are now studies that prove that with the use of 4D differences in fetal behavior can be indeed identified and with these findings eventually abnormal characteristics can be identified [31 - 33]. The commencement of fetal movements has been shown by ultrasound studies th...

Table of contents

• Welcome
• Table of Contents
• Title
• BENTHAM SCIENCE PUBLISHERS LTD.
• FOREWORD
• Principles of 3D/4D Ultrasound: 3D Data Acquisition, Multiplanar Image, 3D Image and Electrical Scalpel (MagiCut)
• Specific Three-Dimensional Display Modes: 3D Cine, 4D, TUI, VCI, Omniview, SonoVCAD, and STIC
• Volume Measurements by Three‐dimensional Ultrasound
• Telemedicine 3D- and 4D-ultrasound in Obstetrics and Gynecology
• Assessment of Fetal Heart by Three- and Four-Dimensional Ultrasound
• Fetal Brain Anatomy by Three-dimensional Ultrasound Neuroscan
• Three-dimensional Assessment of Fetal Face
• Fetal Limb Volume: Its Role in the Prediction of Birth Weight and Evaluation of Fetal Nutritional Status
• Fetal Lung Volumes in Congenital Anomalies Using Three-dimensional Ultrasonography
• Assessment of First Trimester of Pregnancy by Three-dimensional Ultrasound
• The Assessment of Fetal Neurobehavior with Four-dimensional Ultrasound
• Applicability of Three-dimensional Power Doppler Ultrasound in Obstetrics
• Fetal Malformations Detected by Three-dimensional Ultrasound
• Three-dimensional Ultrasound in the Second Stage of Labour
• Three-dimensional Virtual Sonographic and Magnetic Resonance Imaging in Obstetrics
• Uterine Anomalies by Three-dimensional Ultrasound
• Three-dimensional Ultrasound for Assessing the Position of Intrauterine and Intratubal Devices
• Three-dimensional Pelvic Sonography of Uterine Masses
• Three-dimensional Ultrasound in Endometrial Cancer and Polyps
• Assessment of Endometrial Receptivity by Two- and Three-dimensional Ultrasound
• Ovarian Follicle Evaluation: Antral Follicle Count and Follicle Monitoring During Controlled Ovarian Stimulation
• Assessment of Ovarian Volume, Ovarian Follicle Count and Ovarian Blood Flow in Hyper Androgenic Anovulation
• Adnexal Tumors by Three-dimensional Ultrasound
• Three-dimensional Ultrasound for the Assessment of the Pelvic Floor