Torcular Dural Sinus Malformation: Fetal and Postnatal Imaging Findings and Their Associations With Clinical Outcomes

BACKGROUND

Torcular dural sinus malformations (tDSMs) are rare vascular malformations that present in fetuses and infants. Existing data on prognostic imaging features, as well as the associated morbidity and mortality, are limited and variable. We therefore reviewed cases of tDSMs diagnosed on fetal magnetic resonance imaging (MRI) at our referral center to identify pre- and postnatal MRI imaging features associated with long-term outcomes.

METHODS

We searched our imaging database for fetal and postnatal MRI reports of tDSM cases. The electronic medical record was then reviewed for pre- and postnatal clinical data, including follow-up imaging. Neurological outcomes were characterized using the previously reported scale based on the Bicêtre Score. Imaging features association with outcome scores were compared using the Fisher exact test.

RESULTS

Sixteen cases of tDMS diagnosed by fetal MRI with postnatal clinical follow-up were identified, 11 of whom underwent postnatal MRI. The majority of cases of tDSM (73%) decreased in size or resolved on postnatal follow-up study without treatment. Restricted diffusion and parenchymal hemorrhage on fetal MRI were the only imaging features identified significantly associated with unfavorable neurological outcome or death, present in two patients with poor outcomes (two of two) and only one with a normal outcome (one of 14) (P = 0.025).

CONCLUSIONS

Findings of tDSM on fetal MRI most often regress and/or resolve with normal or mild neurological outcomes, with the most significant predictor of poor outcome being the presence of parenchymal injury on fetal MRI. In addition, a subset will present with venolymphatic malformations.

Postnatal outcomes and risk factor analysis for patients with prenatally diagnosed oropharyngeal masses

OBJECTIVES

To describe our experience treating prenatally diagnosed oropharyngeal masses in a novel, multidisciplinary collaboration. To identifying outcomes and risk factors associated with adverse postnatal outcomes.

METHODS

This is a sixty-two patient case series at an academic referral center. Patients with prenatally diagnosed oropharyngeal masses were identified through a programmatic database and confirmed in the electronic health record.

RESULTS

Sixty-two patient with prenatally diagnosed oropharyngeal mass were identified, with prenatal imaging at our institution confirming this diagnosis in fifty-seven patients, short term outcomes analysis conducted on forty-four patients, and long-term outcomes analysis conducted on seventeen patients. The most common pathology was lymphatic malformations (n = 27, 47.4%), followed by teratomas (n = 22, 38.6%). The median mass volume from all available patient imaging (n = 57) was 60.54 cm³ (range 1.73-742.5 cm³). Thirteen pregnancies were interrupted, six infants expired, and thirteen cases had an unknown fetal outcome. Confirmed mortality was 6/57 patients with imaging-confirmed oropharyngeal masses (10.5%). Fourteen (56%) of the surviving patients (n = 25) were delivered by Ex Utero Intrapartum Treatment (EXIT) procedure and the median NICU stay was thirty-six days (range: 3-215 days). There was no association between airway compression/deviation/displacement, stomach size, polyhydramnios, or mass size and mortality. Seventeen patients had more than one year of follow-up (mean 5.3 ± 2.4 years). These seventeen patients underwent general anesthesia a total of ninety-two times (mean 5.4 ± 4.3) and had a total of twenty-three mass-related surgeries. The great majority of patients required an artificial airway at birth, feeding support, and speech/swallow therapy.

CONCLUSIONS

Oropharyngeal mass involvement of key anatomic structures-the neck, upper thorax, orbit, and ear, has a greater association with mortality than mass size. Regardless of the size and involved structures, oropharyngeal masses are associated with a high burden of intensive medical care and surgical care beginning at or before birth.

Risk factor analysis and outcomes of airway management in antenatally diagnosed cervical masses

PURPOSE

To investigate antenatally-determined imaging characteristics associated with invasive airway management at birth in patients with cervical masses, as well as to describe postnatal management and outcomes.

STUDY DESIGN

A retrospective analysis of 52 patients with antenatally diagnosed neck masses was performed using single-center data from January 2008 to January 2019. Antenatal imaging, method of delivery, management, and outcomes data were abstracted from the medical record and analyzed.

RESULTS

Antenatal diagnosis of neck masses in this cohort consisted of 41 lymphatic malformations (78.8%), 6 teratomas (11.5%), 3 hemangiomas (5.8%), 1 hemangioendothelioma (1.9%), and 1 giant foregut duplication cyst (1.9%). Mean gestational age at time of diagnostic imaging was 29 weeks 3 days (range: 19w4d - 37w). Overall, 22 patients (42.3%) required invasive airway management at birth, specifically 18 patients (34.6%) required endotracheal intubation and 4 (7.7%) required tracheostomy. 15 patients (28.8%) underwent ex-utero intrapartum treatment (EXIT) for the purposes of securing an airway. Polyhydramnios, tracheal deviation and compression, and anterior mass location on antenatal imaging were significantly associated with incidence of invasive airway intervention at birth, EXIT procedure, and tracheostomy during the neonatal hospitalization (p < 0.025; Fisher's exact test). Logistic regression analysis demonstrated statistically significant association between increasing antenatally-estimated mass volume and incidence of invasive airway management at birth (p = 0.02). Post-natal cervical mass management involved surgical excision (32.7%), sclerotherapy (50%), and adjuvant therapy with rapamycin (17.3%). Demise in the neonatal period occurred in 4 (7.7%) patients.

CONCLUSION

This series documents the largest single-center experience of airway management in antenatally diagnosed cervical masses. Fetal imaging characteristics may help inform the appropriate method of delivery, airway management strategy at birth, and prenatal counseling.

Neuroaxial Infantile Hemangiomas: Imaging Manifestations and Association with Hemangioma Syndromes

BACKGROUND AND PURPOSE

Infantile hemangiomas are common lesions in the pediatric population; in rare cases, an infantile hemangioma can be detected along the neural axis. The purposes of our study included determination of the incidence, location, and imaging appearance of neuroaxial infantile hemangiomas and their syndromic association. We also assessed additional features of cerebral and cardiovascular anomalies that may be associated with neuroaxial lesions.

MATERIALS AND METHODS

A retrospective cohort study was performed, searching the radiology database for patients with segmental infantile hemangiomas referred for assessment of possible hemangioma syndromes. We retrospectively reviewed brain and spine MR imaging studies, with particular attention paid to neuroaxial vascular lesions, as well as the relevant clinical data. Neuroaxial hemangioma imaging findings were described, and comparison of segmental cutaneous infantile hemangioma location with the imaging findings was performed in patients with confirmed hemangioma syndromes and in patients with isolated skin infantile hemangioma.

RESULTS

Ninety-five patients with segmental infantile hemangioma were included in the study, 42 of whom had a hemangioma syndrome; of those, 41 had posterior fossa brain malformations, hemangioma, arterial lesions, cardiac abnormalities, and eye abnormalities (PHACE) syndrome and 1 had diffuse neonatal hemangiomatosis. Neuroaxial involvement was detected in 20/42 patients (48%) with hemangioma syndromes and in no subjects with isolated segmental infantile hemangioma (P < .001). The most common intracranial hemangioma location was within the ipsilateral internal auditory canal (83%).

CONCLUSIONS

Many pediatric patients with segmental infantile hemangioma in the setting of hemangioma syndromes, especially those with PHACE, had neuroaxial hemangiomas. This finding may potentially lead to requiring additional clinical evaluation and management of these patients.

How to read a fetal magnetic resonance image 101

Accurate antenatal diagnosis is essential for planning appropriate pregnancy management and improving perinatal outcomes. The provision of information vital for prognostication is a crucial component of prenatal imaging, and this can be enhanced by the use of fetal MRI. Image acquisition, interpretation and reporting of a fetal MR study can be daunting to the individual who has encountered few or none of these examinations. This article provides the radiology trainee with a general approach to interpreting a fetal MRI. The authors review the added value of prenatal MRI in the overall assessment of fetal wellbeing, discuss MRI protocols and techniques, and review the normal appearance of maternal and fetal anatomy. The paper concludes with a sample template for structured reporting, to serve as a checklist and guideline for reporting radiologists.

Imaging of fetal brain tumors

Congenital brain tumors, defined as those diagnosed prenatally or within the first 2 months of age, represent less than 2% of pediatric brain tumors. Their location, prevalence and pathophysiology differ from those of tumors that develop later in life. Imaging plays a crucial role in diagnosis, tumor characterization and treatment planning. The most common lesions diagnosed in utero are teratomas, followed by gliomas, choroid plexus papillomas and craniopharyngiomas. In this review, we summarize the pathogenesis, diagnosis, management and prognosis of the most frequent fetal brain tumors.

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.

The Clinical Utility of Flexion-extension Cervical Spine MRI in 22q11.2 Deletion Syndrome

BACKGROUND

Our goal is to correlate the findings on flexion and extension radiographs with dynamic magnetic resonance imaging (MRI), and the clinical history, in a nonrandomly selected cohort of patients with 22q11.2 deletion syndrome (22q).

METHODS

All patients with the 22q who had a dynamic MRI from January 2004 to March 2015 were included. We analyzed multiple radiographic measurements on both the dynamic plain films and the MRIs, and correlated these findings with a review of each patient's medical record.

RESULTS

Multiple congenital anomalies were identified as noted in previous studies, and 61% of the patients had a failure of fusion of the anterior (n=2, 9%), posterior (n=2, 9%), or anterior and posterior arches (n=10, 43%). Quantitative measurements were impossible to report with certainty because of the upper cervical anomalies, and no cases of instability were identified using a qualitative assessment. We identified spinal cord encroachment (30%) and impingement (18%); however, none of the patients had any signal change in their spinal cord. None of these findings could be definitively correlated with any clinical symptoms. A single patient was diagnosed with a Chiari I malformation, while another had cerebellar ectopia.

CONCLUSIONS

Although the upper cervical anomalies are extremely common in 22q, we did not identify cases of instability on dynamic plain radiographs and MRI. Although our findings do not support routine screening with flexion and extension MRI, this study may be required in patients with neurological symptoms and/or findings or abnormalities on dynamic plain radiographs.

LEVEL OF EVIDENCE

Level III.

Imaging of congenital central nervous system infections

Congenital central nervous system (CNS) infections are a cause of significant morbidity and mortality. The recent Zika virus outbreak raised awareness of congenital CNS infections. Imaging can be effective in diagnosing the presence and severity of infection. In this paper we review the clinical presentations and imaging characteristics of several common and less common congenital CNS infections.

Risk of optic pathway glioma in children with neurofibromatosis type 1 and optic nerve tortuosity or nerve sheath thickening

BACKGROUND/AIMS

Optic nerve tortuosity and nerve and sheath thickening are observed on MRI in some patients with neurofibromatosis type 1 (NF-1). This study aimed to determine if tortuosity and thickening are associated with the development of optic pathway glioma (OPG) and subsequent vision loss.

METHODS

Children with NF-1 who underwent brain MRI between 1992 and 2005, and had at least 1 year of subsequent visual acuity (VA) follow-up, were identified retrospectively. The baseline MRI was independently reviewed by three neuroradiologists for consensus assessment. Tortuosity was identified using validated operational criteria. Optic nerve and sheath thicknesses and VA at last follow-up were directly measured.

RESULTS

Of 132 evaluable children, seven (5%) had tortuosity on baseline MRI. 20 subjects (15%) ultimately developed OPG at a median of 1.9 years (range 7 months-8.0 years) following the baseline MRI. Subjects with tortuosity were significantly more likely to develop OPG than those without tortuosity (57% vs 13%, p=0.01). In subjects who developed OPG, the prevalence of tumour-related vision loss was not significantly different between those with and without baseline tortuosity (14% vs 4%, p=0.28). No difference existed between mean baseline optic nerve (2.3 vs 2.2 mm) or sheath (5.2 vs 5.4 mm) thicknesses comparing subjects who did and did not develop OPG.

CONCLUSIONS

Optic nerve tortuosity at baseline is associated with OPG development among patients with NF-1, but does not predispose to aggressive OPG with associated vision loss. Neither nerve nor sheath thickening at baseline is associated with OPG development.

Imaging findings of patients with metastatic neuroblastoma to the brain

RATIONALE AND OBJECTIVES

Metastatic involvement of brain is rare in neuroblastoma (NB). We retrospectively evaluated conventional and advanced imaging and clinical findings of seven patients with secondary intra-axial brain NB metastases.

MATERIALS AND METHODS

Magnetic resonance imaging and computed tomography examinations of patients with metastatic brain NB were reviewed. Recent iodine-123 metaiodobenzylguanidine ((123)I-MIBG) scans were also reviewed. A medical record review was performed for relevant clinical, laboratory, histopathologic, and genetic data.

RESULTS

Mean age at the time of primary tumor diagnosis was 35 months, and all were considered high-risk NB at diagnosis. Mean time interval between diagnosis and brain involvement was 23.2 months. Extensive prior extra-central nervous system (CNS) disease was present in all patients, but concomitant extra-CNS disease at the time of brain involvement was absent in three (43%) patients. Various forms of disease, including intraparenchymal, intraventricular, and leptomeningeal lesions were detected. Most intraparenchymal lesions were supratentorial and hemorrhagic; however, hemorrhage was absent in multiple leptomeningeal nodules in one patient. Contrast enhancement of lesions was present on all contrast-enhanced studies. Restricted diffusion of lesions was present in two patients. Arterial spin labeling (ASL) perfusion in two patients also revealed increased cerebral blood flow. Recent (123)I-MIBG scans were available in four patients and showed lesions in two patients with larger metastases but failed to demonstrate lesions in another two patients with smaller lesions.

CONCLUSIONS

Brain metastases of NB are often supratentorial and hemorrhagic and demonstrate contrast enhancement. Diffusion-weighted imaging can show restricted diffusion. ASL images may reveal increased perfusion. MIBG scans may not show smaller brain metastases.

Brain tumor presenting as somnambulism in an adolescent

BACKGROUND

Sleepwalking is typically a benign and self-limited non-rapid eye movement parasomnia of childhood.

PATIENT

We describe an unusual 15-year-old boy referred to our sleep center for new-onset sleepwalking.

RESULTS

An overnight polysomnogram was normal from a respiratory standpoint, but a concurrent extended electroencephalogram montage showed frequent epileptiform discharges from the right parietal-temporal region and two electroclinical seizures arising from the right-frontal-central-temporal region during sleep. Magnetic resonance imaging scan revealed a right parasagittal parietal region lesion consistent with a low-grade neoplasm, and surgical resection of the lesion demonstrated a right parietal dysembryoplastic neuroepithelial tumor. Complex partial seizures and sleepwalking remitted completely with anticonvulsant therapy following surgery.

CONCLUSIONS

This patient highlights the differential diagnosis of nocturnal events appearing to be typical parasomnias, especially when they arise abruptly at an older age.

CT and MRI of pediatric skull lesions with fluid-fluid levels

Fluid-fluid levels can occur whenever different fluid densities are contained within a cystic or compartmentalized lesion, usually related to the evolution of hematoma or necrosis. Review of the literature demonstrated that throughout the skeletal system, the most common etiology for fluid-fluid levels is aneurysmal bone cyst, but there are no dedicated studies of the pediatric calvaria, to our knowledge. In this report, we present clinicopathologic characteristics and CT and MR imaging of 11 patients with pediatric skull mass lesions demonstrating fluid-fluid levels. MR imaging demonstrated more fluid-fluid levels compared with CT in all cases. The etiologies of skull lesions with fluid-fluid levels were Langerhans cell histiocytosis in 4 (36.6%), aneurysmal bone cysts in 3 (27.2%), cephalohematoma in 3 (27.2%), and metastatic neuroblastoma in 1 (9%). Radiologists should be aware of the other etiologies of calvarial lesions with fluid-fluid levels in the pediatric skull.

Central pontine myelinolysis: a case report and clinical-pathological review

An 11-yr-old child presented with acute mental status changes and spastic quadriplegia after orthotopic liver transplantation. Magnetic resonance (MR) imaging findings were consistent with central pontine and EPM. Initial immunosuppression included tacrolimus, mycophenolate mofetil, and corticosteroids. Given that neurotoxicity is a well-established side effect of CNI, the patient was converted to rapamycin and subsequently experienced significant neurologic recovery. The temporal resolution of the patient's symptoms suggests that prompt recognition of central pontine and EPM and conversion from tacrolimus to rapamycin during the early post-operative course may have therapeutic benefits for patients undergoing pediatric transplant with CNI-related neurotoxicity.

Fetal neuroimaging

Although ultrasound remains the screening modality of choice in evaluation of the fetal nervous system, magnetic resonance imaging with its multiplanar imaging ability and high signal-to-noise ratio is highly accurate in illustrating the morphologic changes of the developing brain and fetal brain abnormalities. Fetal magnetic resonance imaging is an established powerful tool for obtaining additional information in evaluation of anomalies of the fetal face, neck, and spine. It is helpful to patients and their health care professionals in making vital management decisions and aids in genetic counseling for future pregnancies.

Defining optic nerve tortuosity

BACKGROUND AND PURPOSE

Optic nerve tortuosity is one of several nonmalignant abnormalities documented on MR imaging in patients with neurofibromatosis type 1 and may be related to the development of optic pathway gliomas. This study seeks an operational definition for optic nerve tortuosity.

MATERIALS AND METHODS

A focus group of 3 pediatric neuroradiologists reviewed 20 MR images of the brain and orbits of patients suspected to have optic nerve tortuosity in the absence of optic pathway glioma and found 6 radiographic factors that occurred frequently. Subsequently, 28 MR images were assessed for the presence of optic nerve tortuosity, using a global assessment question that reflects a neuroradiologist's confidence in the presence of optic nerve tortuosity, and for the presence of the 6 radiographic factors, to identify a combination of these factors that best predicted a diagnosis of optic nerve tortuosity.

RESULTS

We found perfect inter-rater agreement between 3 readers on the presence/absence of tortuosity in 75% of cases. Lack of congruity of the optic nerves, in more than 1 coronal section and dilation of the subarachnoid space surrounding the optic nerves, when found together are sensitive (89%) and specific (93%) for a diagnosis of tortuosity on the global scale. The absence of these 2 factors, along with absence of deviation of the optic nerve within the axial plane, provides a reliable test to exclude tortuosity.

CONCLUSION

Lack of congruity of the optic nerves in more than 1 coronal section and dilation of the subarachnoid space surrounding the optic nerves together provide an operational radiographic definition of optic nerve tortuosity.

3.0 T versus 1.5 T Pediatric Brain Imaging

This article represents a review of the authors' experience with two 3.0 T Siemens Trio Whole Body MR imaging units, with a cumulative experience of 12 months total imaging time on these scanners, over 1000 cases. The authors were able to identify and review numerous patients who had diagnostic studies both on 1.5 T and 3.0 T.