The role of sonography in the prenatal diagnosis and management of encephalocele

Fetal Occipital Encephalocele: A Case Report

Encephaloceles are considered neural tube defects, but their exact cause is unknown. The outcome is dismal, and essential management and counseling are needed for patients. Two-dimensional and three-dimensional sonography can be used to detect encephaloceles as early as 11 weeks, assist in treatment planning, and improve patient care. This case report presents an occipital encephalocele diagnosed by sonography and followed until delivery.

Congenital lateral encephalocele-case report

Encephalocele is a congenital anomaly where intracranial neural structures extrude from the cranium through a bony and/or a dural defect. They are generally located at the midline and can be diagnosed via prenatal ultrasonography (USG). A very limited number of cases have been reported in the literature about lateral encephalocele. In this paper, the authors present a case with congenital lateral encephalocele which was subsequently operated.

Antenatal Diagnosis of a Rare Neural Tube Defect: Sincipital Encephalocele

Context. Fetal sincipital encephalocele is one of the most serious congenital neural tube defects with a high risk of mortality and neonatal morbidity. Prenatal diagnosis of this malformation is important in fetal medicine. Case Report. We report a case of prenatal diagnosis of sincipital encephalocele using ultrasound and MRI imaging. The diagnosis was done at 25 weeks of gestation by identifying an anterior cephalic protrusion through a defect in the skull. Conclusion. Through this case, we discuss the differential diagnosis, management, and prognosis of such lesions.

Prenatal diagnosis of central nervous system abnormalities

Fetal anomalies have been the subject of innumerable publications both in the prenatal and neonatal literature. This has significantly increased in the last 10 years, mainly because of the advent of high-resolution ultrasound equipment and improvement of scanning techniques. In addition, guidelines issued by professional organizations involved in prenatal diagnosis have encouraged a more universal approach to the imaging and documentation of prenatal findings. The fetal central nervous system is the most frequently investigated organ system, mainly because of its easy accessibility and prominence even in the early stages of embryologic development. The biparietal diameter was the first fetal measurement to be widely used in determining gestational age. As investigators gained more experience, the appearance of ultrasound images achieved the resolution that allows direct comparisons with gross specimens and more recent sophisticated techniques of computed tomography and magnetic resonance imaging. Now endovaginal ultrasound can document early first trimester development and compare it to known embryologic landmarks. Interest in demonstrating the ultrasound counterpart of central nervous system structures in the early stages of development has resulted in a plethora of articles proving the unique ability of ultrasound in imaging the developing fetus. In view of all these developments, the beginning ultrasound specialist is faced with the challenge and responsibility not only of being familiar with the literature but also of the mastery of scanning techniques that allow accurate prenatal diagnosis. It is therefore helpful to review key developmental milestones in embryologic life and correlate them with the corresponding prenatal ultrasound appearance. In addition, the changing appearance of the developing fetus has created a need for a systematic approach in the evaluation of structures so routine protocols can be established. This has been the subject of other publications that allow the novice to draw from the cumulative experience of different centers around the world. It is important to pay attention to the specifics described in the literature when duplicating results in one's laboratory. The frustration of not being able to reproduce results is common, especially when technical limitations prevent imaging under ideal conditions. This is especially true in patients who are first seen in the later third trimester with no prior prenatal care.(ABSTRACT TRUNCATED AT 400 WORDS)

A ten-year review of encephalocele in a teaching hospital

A 10-year review of infants with encephalocele was carried out in a multicentered teaching hospital. Out of 23,438 infants seen within the period, only 12 cases of encephalocele were seen, giving an incidence of 0.5/1000 births. Nine (75%) of patients had occipital encephalocele, two (16.7%) occipitoparietal and one (8.3%) fronto-nasal. Two patients had spina bifida as an associated neural tube defect while ocular abnormalities were seen in another two. None had neurological defects at birth but some showed evidence of hydrocephalus and delayed milestones after surgery. Ultrasonic diagnosis was made in one case only. The etiologic, prognostic and descriptive characteristics, in addition to obstetric management of encephalocele are discussed.

The fetal spine

Ultrasonography has made it possible to evaluate the fetal spine in utero. Vertebral ossifications are demonstrable by ultrasonography in the early second trimester. Most spinal defects are apparent by 20-22 weeks menstrual age. Early detection of spinal anomalies allows for parental counseling and appropriate obstetrical management. Real-time equipment allows the fetal spine to be examined in parasagittal, transverse and coronal planes. The transverse plane provides the best view of the three ossification centers that form each fetal vertebra. Evaluation of the neural arch ossifications in the transverse view is crucial in detecting spina bifida defects. Ultrasonography of the fetal spine complements the use of alpha-fetoprotein levels in screening for neural tube defects. Examination of the fetal spine is also important in detecting vertebral ossification defects, particularly in cases of short-limbed dwarfs and infants of diabetic mothers.

Prenatal detection of fetal anomalies with sonography

This article has presented an overview of the sonographic detection of fetal anomalies. Fortunately, fetal anomalies are relatively rare, but the information that is obtained with sonography can facilitate obstetric management and counseling of the expectant parents.

Differential diagnosis of sonographically detected tumours in the fetal cervical region

Differential diagnosis of sonographically detected fetal neck tumours is difficult. The sonographic criteria for encephalomyelocele, lymphangioma/hygroma, teratoma, sarcoma, haemangioma, neuroblastoma and goitre are given on the basis of the authors' own observations and information from the literature. Elevation of alpha-fetoprotein in the amniotic fluid is a frequent but non-specific finding. Chromosome analysis after amniocentesis can be a useful supplementary procedure for assessing the prognosis and deciding upon the delivery procedure. Sonographic detection of a tumour in the fetal neck region enables preparations to be made for dystocia and postnatal dyspnoea of the newborn. The obstetrician must cooperate closely with paediatricians, neurologists, surgeons and ENT specialists.

The diagnosis of fetal hydrocephalus

Thirty cases of fetal hydrocephalus were diagnosed at the perinatal ultrasound unit of Yale-New Haven Medical Center during a 41 month period. Prenatal ultrasound was found to be highly valuable in the detection of fetal hydrocephalus. However, the antenatal detection of associated anomalies was not as uniformly successful. The importance of a complete sonographic evaluation of intracranial and extracranial anatomy is stressed, as 10 patients with documented hydrocephalus (37%) had associated intracranial anomalies and 17 patients (63%) had associated extracranial anomalies. In this series, isolated hydrocephalus without associated anomalies occurred in only four patients (15%).