MR imaging of fetal head and neck anomalies

Clinical spectrum of orbital and ocular abnormalities on fetal MRI

BACKGROUND

Fetal magnetic resonance imaging (MRI) may reveal sonographically occult ocular abnormalities. When discovered, acquired causes and genetic associations must be sought.

OBJECTIVE

We aim to evaluate a fetal cohort with orbit and/or globe malformations to determine whether there are imaging patterns that suggest the underlying cause.

MATERIALS AND METHODS

We searched all fetal MRI reports performed at an academic children's hospital over 9 consecutive years for orbit and/or globe abnormalities. Each positive exam and all follow-up MRIs were evaluated for interocular distance, globe size, shape and signal, and brain malformations. Genetic and clinical diagnoses were recorded from the medical record.

RESULTS

Seventy-six of 3,085 fetuses (2.5%) were diagnosed with ocular and/or globe abnormalities; 50% had postnatal follow-up MR exams, all confirming the fetal MRI findings. Ninety-two percent (70/76) had concurrent brain malformations. Sixty-seven percent (51/76) were diagnosed with an underlying disorder and 39% of these were genetically proven. The most common diagnoses with ocular globe abnormalities included CHARGE (coloboma of the eye, heart anomaly, choanal atresia, retardation and genital and ear anomalies) syndrome, trisomy 13 syndrome, dystroglycanopathy, holoprosencephaly and diencephalic-mesencephalic junction dysplasia. Genetic diagnoses were more likely with ocular globe abnormalities than isolated orbital abnormalities (P=0.04). Sixty-seven percent of fetuses with ocular calcifications, hemorrhage and/or lens abnormalities had potential maternal risk factors (P=0.03).

CONCLUSION

Malformed ocular globes are associated with brain malformations and genetic abnormalities. Ocular calcifications, hemorrhage and/or lens abnormalities may be associated with maternal risk factors. Genetic work-up should be considered when an ocular globe size or shape abnormality is detected.

Fetal head and neck tumors

Imaging plays a leading role in detection and diagnosis of fetal head and neck lesions. These lesions comprise a heterogeneous group of congenital tumors and malformations. Complementary imaging modalities that can be used in prenatal medicine are ultrasound and MRI. The authors discuss imaging characteristics of fetal lesions, assessment of potential complications and pregnancy management options for the most common pathology of the fetal head and neck.

Spotlight on the pediatric eye: a pictorial review of orbital anatomy and congenital orbital pathologies

Orbital lesions in the pediatric population vary from adults in terms of their presentation, unique pathology, and imaging characteristics. The prompt and accurate diagnosis of these lesions is imperative to prevent serious consequences in terms of visual impairment and disfigurement. Along with dedicated ophthalmologic examination, imaging is instrumental in characterizing these lesions, both for accurate diagnosis and subsequent management. In our pictorial essay, we provide a basic review of orbital embryology, anatomy, and congenital orbital pathologies, with emphasis on radiological findings.

Fetal brain, head, and neck tumors: Prenatal imaging and management

Fetal tumors represent an infrequent pathology when compared to congenital malformations, although their true incidence may be underestimated. A variety of benign and malignant neoplasms may occur anywhere in the neural axis. Imaging plays an important role in the fetal tumor diagnosis and evaluation of their resultant complications. Discovery of a fetal mass on obstetric ultrasound necessitates further evaluation with prenatal magnetic resonance imaging (MRI). New MR sequences and new applications of existing techniques have been successfully implemented in prenatal imaging. A detailed assessment may be performed using a variety of MR. Fetal tumors may be histologically benign or malignant, but their prognosis generally remains poor, especially for intracranial lesions. Unfavorable tumor location or heightened metabolic demands on a developing fetus may result in severe complications and a fatal outcome, even in cases of benign lesions. Nowadays, prenatal treatment focuses mainly on alleviation of secondary complications caused by the tumors. In this article we review congenital tumors of the brain, face, and neck encountered in prenatal life, and discuss diagnostic clues for appropriate diagnosis.

MR Imaging of the Fetal Face: Comprehensive Review

The human face is a complex anatomic structure with an equally complex embryologic development. Derangement of the developmental process can result in various structural anomalies, which range from a mainly cosmetic deformity, such as cleft lip, to potentially life-threatening conditions such as arhinia. These anomalies (a) can occur as isolated anomalies; (b) can be associated with intracranial, spinal, or dental anomalies; or (c) can be a part of various syndromes, thus serving as diagnostic clues in such cases. Proper evaluation of fetal facial deformities can help in prognostication, family counseling, and prenatal or early postnatal intervention. Ultrasonography (US) is the first line of investigation in these cases. However, when US does not allow complete evaluation of these anomalies owing to its inherent limitations, magnetic resonance (MR) imaging allows comprehensive evaluation of the anomaly itself and also evaluation of various associations and the treatment approach. The embryology of the fetal facial structures is considered with regard to the MR imaging technique and the MR imaging anatomy. The MR imaging features of various structural anomalies are described and classified into six groups, namely, orofacial clefts, orbital anomalies, nasal anomalies, facial masses, external ear anomalies, and abnormal face shape or profile. Also, the key associations and relevant treatment implications are reviewed. The article provides a "one-stop shop" review of these unique disorders-from basic understanding of the embryology to applying the knowledge in clinical practice, helping the interprofessional team and the patients alike. ^©RSNA, 2018.

Integrating 3D Sonography With Targeted MRI in the Prenatal Diagnosis of Posterior Cleft Palate Plus Cleft Lip

Cleft lip and cleft palate are among the more common congenital abnormalities, present in 1.82 per 1000 live births. Although high-quality antenatal 2D sonography can diagnose clefts of the lips and the alveolar ridge, 3D may enhance detection by examining the fetal face in the frontal plane followed by a secondary rotation through 180 degrees on the vertical axis to examine the secondary palate, which has been called the “reverse face” view. Sonographically 3D targeted ultrafast magnetic resonance imaging (MRI) has been shown to improve the diagnostic accuracy of facial cleft by identifying whether a cleft in the primary palate extends to the secondary palate. Further investigation may confirm the ability of MRI to define the extent of the cleft to the secondary palate at a less advanced gestational age (18-23 weeks), where either fetal development or movements could reduce the accuracy of the technique.

Anophthalmia and serious microphthalmia: a summary of the problems associated with antenatal diagnosis and therapeutic refunding in Sub-Saharan Africa

Anophthalmia and serious microphthalmia are conditions characterized by the complete lack of the primary optic vesicle or the presence of the rudimentary eye-like structure. These are rare prenatal conditions, yet diagnoses remain a challenge in Black African areas, raising a major concerns surrounding care after birth. This paper reports a case of anophthalmia and serious microphthalmia, the diagnosis of which was not possible despite many ultrasounds undergone by the mother during pregnancy.

Imaging evaluation of fetal vascular anomalies

Vascular anomalies can be detected in utero and should be considered in the setting of solid, mixed or cystic lesions in the fetus. Evaluation of the gray-scale and color Doppler US and MRI characteristics can guide diagnosis. We present a case-based pictorial essay to illustrate the prenatal imaging characteristics in 11 pregnancies with vascular malformations (5 lymphatic malformations, 2 Klippel-Trenaunay syndrome, 1 venous-lymphatic malformation, 1 Parkes-Weber syndrome) and vascular tumors (1 congenital hemangioma, 1 kaposiform hemangioendothelioma). Concordance between prenatal and postnatal diagnoses is analyzed, with further discussion regarding potential pitfalls in identification.

Prenatal diagnosis and management of nasal glioma

Advances in foetal imaging have increased our detection rate of craniofacial abnormalities in utero. Nasal glioma is a rare, benign, congenital facial defect. Once detected, further imaging is required to assess for intracranial communication, the presence of additional defects, determine the patency of the aerodigestive tract and decide on timing of delivery. The authors review the current literature on diagnosis and management of nasal glioma in this rapidly advancing field of craniofacial anomalies detected in utero. Literature search of EMBASE and MEDLINE databases yielded 594 articles, which were screened by 2 independent reviewers. A total of 7 papers were selected after exclusion. There have been seven cases of prenatally diagnosed nasal glioma. The earliest of these was detected at 20 wk gestation. The majority were investigated with foetal magnetic resonance imaging (MRI) to establish any intracranial communication or bony defects. Ultrasound monitoring, doppler waveform and 3D rendered images were utilised to delineate the lesion, monitor growth and differentiate potential diagnosis. Postnatal MRI is favoured by most to re-evaluate the lesion and aid surgical planning. Surgical resection was performed within the first few months of life. Diagnostic uncertainty was seen in all cases, until formal histology was obtained, emphasising the challenges, and need for early appropriate specialist input. Whilst the prenatal detection of craniofacial abnormalities increases, there remain diagnostic challenges in differentiating prenatal congenital midfacial defects in utero. These defects are best investigated and monitored using prenatal ultrasound and MRI, to narrow the differential diagnosis, guide timing of delivery and allow for appropriate surgical planning. Prenatally detected nasal glioma, may only be confirmed on histology and families must be counselled appropriately to prepare them for the possible alternative diagnoses. Early surgical resection was undertaken to achieve more favourable aesthetic outcomes, reduce complications of ocular development and provide definitive histological diagnosis.

Magnetic resonance imaging in the prenatal diagnosis of neural tube defects

OBJECTIVE

To assess the role of magnetic resonance imaging (MRI) in the prenatal diagnosis of neural tube defects (NTDs).

BACKGROUND

NTDs comprise a heterogeneous group of congenital anomalies that derive from the failure of the neural tube to close. Advances in ultrasonography and MRI have considerably improved the diagnosis and treatment of NTDs both before and after birth. Ultrasonography is the first technique in the morphological study of the fetus, and it often makes it possible to detect or suspect NTDs. Fetal MRI is a complementary technique that makes it possible to clear up uncertain ultrasonographic findings and to detect associated anomalies that might go undetected at ultrasonography. The progressive incorporation of intrauterine treatments makes an accurate diagnosis of NTDs essential to ensure optimal perinatal management. The ability of fetal MRI to detect complex anomalies that affect different organs has been widely reported, and it can be undertaken whenever NTDs are suspected.

CONCLUSION

We describe the normal appearance of fetal neural tube on MRI, and we discuss the most common anomalies involving the structures and the role of fetal MRI in their assessment.

KEY POINTS

• To learn about the normal anatomy of the neural tube on MRI • To recognise the MR appearance of neural tube defects • To understand the value of MRI in assessing NTDs.

Fetal MRI: head and neck

Abnormalities of the fetal head and neck may be seen in isolation or in association with central nervous system abnormalities, chromosomal abnormalities, and syndromes. Magnetic resonance imaging (MRI) plays an important role in detecting associated abnormalities of the brain as well as in evaluating for airway obstruction that may impact prenatal management and delivery planning. This article provides an overview of the common indications for MRI of the fetal head and neck, including abnormalities of the fetal skull and face, masses of the face and neck, and fetal goiter.

Prenatal diagnosis and management of a craniofacial glioma detected at 20 weeks' gestation. Case report and review of the literature

Foetal imaging and anomaly detection is advancing at a rapid rate. As a result, detection of foetal craniofacial abnormalities is increasing. Ultrasound and magnetic resonance imaging are currently the imaging modalities most commonly used. The authors describe the detection of a nasal glioma at 20 weeks' gestation, subsequent prenatal monitoring and postnatal management with surgical excision at 2 months of age. The world literature regarding prenatal diagnosis and management of craniofacial malformations is discussed.

Nasopharyngeal cysts

INTRODUCTION

Nasopharyngeal cysts are uncommon, and are mostly asymptomatic. However, these lesions are infrequently found during routine endoscopies and imaging studies. In even more rare cases, they may be the source for unexplained sinonasal symptoms, such as CSF rhinorrhea, visual disturbances and nasal obstruction.

PURPOSE OF REVIEW

This presentation systematically reviews the different nasopharyngeal cysts encountered in children, emphasizing the current knowledge on pathophysiology, recent advances in molecular biology and prenatal diagnosis, clinical presentation, imaging and treatment options.

SUMMARY

With the advent of flexible and rigid fiber-optic technology and modern imaging techniques, and in particularly prenatal diagnostic techniques, nasopharyngeal cysts recognition is more common than previous times and requires an appropriate consideration. Familiarity with these lesions is essential for the pediatric otolaryngologist.

MRI of the fetal central nervous system and body

MRI is being increasingly used to assess for fetal abnormalities. Although significant progress in the field of fetal MRI has occurred during the past 20 years, continued technical advances will likely contribute to significant growth of the field. Moreover, with continued hardware and software improvements, additional MRI sequences will likely become available. Prenatal MRI complements ultrasound because of larger field-of-view, superior soft tissue contrast, easier and more precise volumetric measurement, and greater accuracy in the demonstration of intracranial and spinal abnormalities. While ultrasound remains the primary modality for fetal imaging, these advantages of MRI make it a valuable adjunct to fetal surgery. Because fetal MRI involves many disciplines, the future of fetal MR will best be achieved through collaborative efforts.

MRI of the fetal eyes: morphologic and biometric assessment for abnormal development with ultrasonographic and clinicopathologic correlation

BACKGROUND

Currently ocular biometric measurements are defined by US and are measured from the orbital walls. These bony landmarks cannot be seen by MRI, and therefore these measurements cannot be directly applied.

OBJECTIVE

To define measurements of normal growth of the fetal eyes using MRI.

MATERIALS AND METHODS

Transorbital views were analyzed in 198 fetal MR examinations. The ocular diameter (OD) and interocular and binocular distances (IOD and BOD) were measured and were plotted against gestational age. Fetuses with abnormalities affecting the eyes were evaluated separately.

RESULTS

Of 198 scans, 146 had suitable images, 35 of which were abnormal. Normal growth of BOD, IOD and OD were determined, and compared with the respective already established US data.

CONCLUSION

Normal growth charts were derived from a cohort of 111 normal fetuses. Because the margins of the vitreous are inside the bony orbit, at the same gestational age measurements of the BOD and OD are always less than the corresponding measurements by US, and those of the IOD are always more. Normal growth charts for MRI can now be used to support suspected diagnoses of orbital and ocular pathologies and the syndromes that give rise to them, and many examples are demonstrated.

Diagnosis of pentalogy of cantrell in the fetus using magnetic resonance imaging and ultrasound

We report two cases of pentalogy of Cantrell diagnosed in utero using a combination of fetal echocardiography and magnetic resonance imaging. The cardiac component consisted of tetralogy of Fallot in the first fetus and ventricular septal defect in the second fetus. Whereas fetal echocardiography allowed accurate delineation of the cardiac anatomy, prenatal magnetic resonance imaging allowed clearer delineation of the extent of the thoracic and abdominal wall defects. Fetal magnetic resonance imaging in conjunction with prenatal echocardiography allows optimal assessment of the fetus with ectopia cordis, which has significant implications from the standpoint of preoperative planning and providing prognostic information. This report represents the first description of applying magnetic resonance imaging in combination with echocardiography toward a better understanding of this clinical entity in the fetus.

Prenatal diagnosis of craniosynostosis: value of MR imaging

INTRODUCTION

The aim of our study was to assess the utility and reliability of magnetic resonance imaging (MRI) in antenatal diagnosis of craniosynostosis.

METHODS

We retrospectively reviewed the MRI examinations of the head of 15 fetuses requested over a period of 11 years on the basis of sonographic suspicion of craniosynostosis. The postnatal diagnosis was available for 14 neonates.

RESULTS

No termination of pregnancy was performed. There were four neonates with sporadic multisuture craniosynostoses, three of which were syndromic, including one Crouzon and one Pfeiffer syndrome. Eight neonates were normal, two showed cranial vault deformities without synostosis, and one was lost to follow-up. MRI showed a high predictive value for craniosynostosis, as there were no false-negative or false-positive diagnoses. However, the severity of the abnormalities were underestimated in two neonates.

CONCLUSION

We suggest that prenatal MRI has diagnostic value when synostosis is suspected on ultrasonography. Moreover, MRI is accurate in the detection of associated brain abnormalities, which is an important prognostic issue in this diagnosis. Prenatal diagnosis of craniosynostosis is difficult and could benefit from three-dimensional ultrasonography and three-dimensional CT.

Neuroimaging of the child with developmental delay

Developmental delay (DD) affects approximately 1% to 3% of all children in the United States. This diagnosis significantly impedes quality of life and full participation in the life of the family, school, and community. In this setting, the clinician's ability to detect, diagnose, and possibly treat the cause for DD in a timely manner depends on a multimodality approach to neuroimaging and a robust understanding of the various imaging algorithms aimed at determining the etiology of disease, structural and/or anatomic defects, functional activity, metabolic profiles, and genetic characteristics. Taken separately and in combination, these features are effectively depicted and analyzed using an array of brain imaging modalities: ultrasound, computed tomography, nuclear medicine, magnetic resonance (MR) spectroscopy, and a growing mix of sophisticated MR imaging (MRI) techniques, including diffusion-weighted imaging, diffusion tensor imaging, perfusion MRI, and functional MRI. Thus, equipped with these advanced imaging capabilities, pediatric neurologists and neuroradiologists are now positioned to diagnose with greater accuracy and speed; this, in turn, results in more effective treatment plans and improved patient outcomes as measured by progress in reaching developmental milestones and in ameliorating secondary conditions such as seizures, poor motor control, incontinence, and impulsivity. The purpose of this article is to present the numerous causes of pediatric DD, describe their respective neuroimaging findings, discuss various neuroimaging approaches for elucidating etiology, and offer specific guidelines for optimizing imaging results in the setting of multimodality imaging capabilities.

Fetal MR Imaging

Ultrasonography is the primary prenatal screening modality used in the evaluation of the fetus and the maternal pelvis. However, fetal MR imaging plays a complementary role to prenatal ultrasound in the evaluation of the fetus with suspected abnormalities. MR imaging's role includes confirming or excluding possible lesions, defining their full extent, aiding in their characterization, and demonstrating other associated abnormalities. As newer techniques such as diffusion imaging, MR spectroscopy, and functional studies are used more widely, it is hoped that additional information will be made available by this modality to physicians evaluating and taking care of fetuses.

Liver, meconium, haemorrhage: the value of T1-weighted images in fetal MRI

BACKGROUND

Ultrafast T2-weighted (T2-W) MRI sequences are currently considered a routine technique for fetal MR imaging. Limited experience exists with fetal T1-weighted (T1-W) imaging techniques.

OBJECTIVE

To determine MRI patterns of some fetal abdominal or haemorrhagic disorders with particular respect to the diagnostic value of T1-W images.

MATERIALS AND METHODS

In addition to standard T2-W single-shot sequences, T1-W single-shot and/or multislice sequences were employed in 25 MR examinations performed in 23 fetuses between 20 and 36 weeks of gestation for more detailed assessment of liver, meconium-filled digestive tract, haemorrhage, or further characterization of a fetal abdominal mass. Diagnostic value and presence of motion artefacts on T1-W images was recorded in each case.

RESULTS

T1-W images enabled superior delineation of fetal liver and large intestine. They provided additional diagnostic information in 9 (39%) of 23 fetuses. One false-positive and one false-negative MRI diagnosis of malrotation anomaly were encountered. Use of single-shot T1-W sequences reduced the occurrence of motion artefacts in 64%.

CONCLUSION

Our results suggest that the specific signal properties of methaemoglobin, meconium and liver are sufficiently important for T1-W sequences to become a routine part of fetal MRI protocols when dealing with digestive tract anomalies, diaphragmatic and abdominal wall defects, intraabdominal masses, and fetal haemorrhage.

Primary thyroid teratomas in children: a report of 11 cases with a proposal of criteria for their diagnosis

Cervical teratomas are uncommon neoplasms, although the commonest neck tumors in newborns and infants. Presence of associated thyroid tissue often causes speculation as to the site of origin, ie, arising from within thyroid, adjacent soft tissue with secondary involvement of thyroid, or as innate part of a cervical teratoma. Twenty-eight cases of cervical teratomas were identified over 75 years, including 11 cases containing associated thyroid tissue. Clinical history, treatment, and follow-up were reviewed and the neoplasms analyzed regarding location, size, degree of maturity, and relative arrangement of thyroid and other tissues. All thyroid teratomas were congenital, measured 3.5 to 13.5 cm in diameter (median size, 6.9 cm), and were resected. Follow-up ranged from 1 to 45 years (median, 17 years) without recurrent disease in any patient. Neuroglial tissue predominated in 10 of 11 tumors. Intimate admixture of thyroid and other tissues with or without surrounding fibrous pseudocapsule was present in 8 cases, suggesting thyroid as origin. Histologic immaturity in congenital thyroid teratomas is not the harbinger of adverse behavior as seen in adolescents and adults. Intimate intermingling of thyroid tissue with teratoma and presence of a pseudocapsule seem to be the most significant criteria for establishing thyroid as origin.