Pediatric Neurosurgery - part 3 pot

42 Pediatric Neurosurgery 2 Figure 27. Large, left, hemispheric, irregular, heterogeneous, dense, enhancing PNET with cystic components and punctate calcifications. (CT, FLAIR, T1-WI with contrast) 43 Diagnostic Imaging 2 Table 11. Sellar and suprasellar tumors Tumor Type Location Imaging Appearance Other Features Figures Astrocytoma Hypothalamus and/or optic Lobulated hypodense solid mass Visual deficits and optic 28 chiasm ↓ T1 and ↑ T2 SI disc atrophy Variable enhancement Endocrinopathy If large, can be heterogeneous Associated with NF1 Craniopharyngioma Along hypothalamic stalk Multicystic, suprasellar, enhancing mass Headaches 29, 30 between floor of third with calcification Visual deficits ventricle and pituitary gland Rarely intrasellar Endocrine dysfunction Usually suprasellar; large Variable T1 and ↑ T2 SI (e.g., diabetes insipidus, tumors can extend beyond growth failure) suprasellar area Germinoma Involve stalk and extend into Well-defined, slightly heterogeneous mass Diabetes insipidus is 31 hypothalamus Iso- or hyperdense common ↓ T1 and mixed T2 SI Enhancement Granulomatous Hypothalamus and infundibulum Enlarged infundibulum Hypothalamic-pituitary disease Enhancement dysfunction (TB and sarcoid) Hypothalamic Tuber cinereum of Well-defined oval mass Precocious puberty 32 hamartoma hypothalamus, between Isodense and isointense to gray matter Gelastic seizures mammillary bodies No enhancement Developmental delay ↑ = increased; ↓ = decreased; NF1 = neurofibromatosis type 1; SI = signal intensity continued on next page 44 Pediatric Neurosurgery 2 Table 11. Continued Tumor Type Location Imaging Appearance Other Features Figures Langerhans cell Hypothalamus, infundibulum Enlarged infundibulum Hypothalamic-pituitary histiocytosis and pituitary Enhancement dysfunction Often indistinguishable from GCT, granulomatous process and lymphocytic hypophysitis Lymphocytic Anterior pituitary and Enlarged hypothalamus and infundibulum Headache hypophysitis hypothalamus Enhancement Visual deficit Hypothalamic-pituitary dysfunction Pituitary adenoma Pituitary gland (intrasellar) Well-defined mass Headaches 33 Large adenomas can extend ↓ T1 SI Visual deficits into suprasellar compartment, Less enhancement than surrounding Endocrine dysfunction and compress optic chiasm normal gland (e.g., amenorrhea, Cushing’s disease) Rathke’s cleft cyst Pituitary gland (intrasellar) Well-defined oval mass Headache 34 Variable T1 and T2 SI Visual deficit No enhancement Hypothalamic-pituitary dysfunction ↑ = increased; ↓ = decreased; GCT = germ-cell tumor; SI = signal intensity 45 Diagnostic Imaging 2 Figure 28. Chiasmatic astrocytoma. Homogeneously enhancing suprasellar mass. The chiasm cannot be defined. (coronal T1-WI with contrast) Figure 29. Craniopharyngioma. Lobu- lated hypodense suprasellar mass with peripheral calcifications. (transaxial CT) Figure 30. Large multicystic craniophar- yngioma. (sagittal T1-WI with contrast) Figure 31. Suprasellar germinoma with extension inferiorly along the pituitary stalk. (coronal T1-WI with contrast) 46 Pediatric Neurosurgery 2 Figure 32. Hypothalamic hamartoma. Small nonenhancing nodule that is isointense to gray matter, and located in the hypothalamic region. (coronal T2-WI, sagittal T1-WI with contrast) Figure 33. Pituitary adenoma filling the sella and extending into the suprasel- lar space. (coronal and sagittal TI-WI with contrast) Figure 34. Rathke’s cleft cyst. Well- defined oval focus of decreased en- hancement in the midline upper pitu- itary gland, abutting the optic chiasm. (coronal T1-WI with contrast) 47 Diagnostic Imaging 2 Table 12. Pineal region masses Mass Location Imaging Appearance Other Features Figures Germinoma Pineal or suprasellar regions, See Table 11 Disseminate via CSF 35 and, rarely, deep gray nuclei Pineal germinomas have Most common (>50%) pineal 10:1 M:F ratio region tumor Can secrete placental alkaline phosphatase Glioma Quadrigeminal plate, or Hypodense Large parapineal gliomas can medial temporal or ↓ T1 and ↑ T2 SI be difficult to distinguish from occipital lobes Enhancement primary pineal tumors Pineal cyst Pineal gland Well-defined homogeneous cyst Never causes hydrocephalus 36 Isodense, T1-isointense and ↑ T2 SI relative to CSF Uncommon in infants Peripheral rim of enhancement Non-neoplastic Pineocytoma and Pineal parenchyma Lobulated mass containing calcification Pineoblastomas are highly 37 pineoblastoma Enhancement malignant, invasive and can Hypodense spread via CSF Isointense, or ↓ T1 SI and isointense, or ↑ T2 SI Teratoma Pineal or suprasellar region, Heterogeneous mass with fat and calcification Most are benign, but few can third ventricle, or midline Heterogeneous T1 and T2 SI; ≠ T1 SI due to fat be highly malignant posterior fossa Variable enhancement Male predominance ↑ = increased; ↓ = decreased; CSF = cerebrospinal fluid; SI = signal intensity 48 Pediatric Neurosurgery 2 Figure 35. Germinoma. Slightly heterogeneous, mildly enhancing T1-hypointense, T2-hyperintense mass in the pineal region. (transaxial T1-WI with contrast, and T2-WI) Figure 36. Pineal cyst. Well-defined homogeneous (nonenhancing) T1-hypointense and T2-hyperintense cyst-like mass in the pineal region. (sagittal T1-WI, and transaxial T2-WI) Figure 37. Pineo- blastoma causing noncommunicating hydrocephalus. (transaxial T1-WI, without and with contrast) 49 Diagnostic Imaging 2 Table 13. Congenital brain malformations Malformation Clinical Features Imaging Features Other Associations Figures Agenesis of Developmental delay Absence of corpus callosum Interhemispheric cyst 38 corpus callosum Seizures Parallel configuration of lateral ventricles Chiari II Colpocephaly (enlarged atria and occipital Dandy-Walker malformation horns of lateral ventricles) Septo-optic dysplasia “High-riding” third ventricle Neuronal migrational Absence of cingulate sulcus anomalies Sagittal and coronal MR sequences helpful Chiari I Headaches Cerebellar tonsils > 5 mm below foramen Segmentation anomalies of 39 (Inferior cerebellar Lower cranial-nerve palsies magnum cervical spine tonsillar ectopia) Swallowing difficulties Small posterior fossa Always evaluate for Dysesthesias Hydrocephalus and syringohydromyelia syringohydromyelia in may be present spinal cord Consider CSF flow study Chiari II Uniformly seen in association Small posterior fossa Subependymal heterotopias 40 with myelomeningocele Inferior cerebellar vermis displaced through Aqueductal stenosis at birth the foramen magnum Hindbrain malformation Development delay Hydrocephalus associated with Lower cranial nerve palsies “Beaked” tectum myelomeningocele leading to dysphagia Callosal hypogenesis or stridor Hypoplastic falx with gyri interdigitated across midline Cervicomedullary kink Large massa intermedia CSF = cerebrospinal fluid continued on next page 50 Pediatric Neurosurgery 2 Table 13. Continued Malformation Clinical Features Imaging Features Other Associations Figures Dandy-Walker Defined as a cystic Large posterior fossa A spectrum of posterior fossa 41 malformation malformation of the High insertion of torcula anomalies that includes (DWM) posterior fossa Vermian hypogenesis Dandy-Walker variant and Macrocephaly Fourth ventricle communicates with large mega cisterna magna Developmental delay posterior fossa cyst Callosal hypogenesis Seizures Hydrocephalus Migrational anomaly Headaches Gray matter Seizures Nonenhancing nodules that are Callosal dysgenesis 42 heterotopias Can be asymptomatic isointense to gray matter, and located Cerebellar malformations Can have additional mild along lateral ventricles or subcortical Gray matter in abnormal motor and intellectual regions locations due to arrested deficits radial neuronal migration Holoprosencephaly Varies with severity of Absent septum pellucidum Trisomies 13 and 18 43 malformation Alobar type: severe Failure of induction of the Dysmorphic facial features Absent callosum, falx and interhemispheric rostrobasal prosencephalon Midline facial clefts fissure; monoventricle; fused thalami Hypotelorism Semilobar type: intermediate Seizures Partially absent callosum, falx and Developmental delay interhemispheric fissure +/- thalamic Hypothalamic-pituitary fusion; monoventricle dysfunction Lobar type: mild Near normal ventricles, falx, callosum and thalami continued on next page 51 Diagnostic Imaging 2 Table 13. Continued Malformation Clinical Features Imaging Features Other Associations Figures Lissencephaly Seizures Lack of sulcation Congenital CMV infection 44 (“Smooth brain”) Developmental delay Thickened cerebral cortex (pachygyria) Callosal dysgenesis Abnormal neuronal Decreased white matter volume Congenital heart disease migration Polymicrogyria Seizures Disruption of normal cortical organization Dense polymicrogyria can 45 (“Too many Developmental delay Fine excessive irregularity of cortex, focal mimic pachygyria small gyri”) or diffuse Congenital CMV infection Occasional ↑ T2 SI of underlying white matter Occasional calcification Schizencephaly Seizures Full thickness cleft, extending from pial Can be “open-lip“ or “closed-lip,” 46 Developmental delay surface to ventricle depending on apposition of Motor deficits Cleft lined with gray matter cleft’s walls (and polymicrogyria) Distinguish from porencephaly, Involves one or both cerebral hemispheres which is a cleft lined with Commonly in frontal or parietal lobes gliotic white matter Septo-optic Variable Hypoplasia or absence of septum pellucidum Mild callosal dysgenesis dysplasia Hypoplasia of optic discs Hypoplasia of optic nerves and chiasm Can be difficult to distinguish (de Morsier’s Hypothalamic-pituitary from lobar holoprosencephaly Syndrome) dysfunction ↑ = increased; CMV = cytomegalovirus [...]... component) Syringohydromyelia due to spinal-cord hemangioblastomas Imaging Features Figures Diagnostic Imaging 57 2 58 Pediatric Neurosurgery 2 Figure 47 NF1 Enhancing T1-hypointense mass along the optic chiasm Enlargement of optic nerves (sagittal T1-WI, without and with contrast) Figure 48 NF1 Areas of T2-hyper-intensity represent abnormal areas of myelination (coronal T2-WI) Figure 49 NF1 Bilateral enhancing... gray-matter heterotopias along the lateral margins of the ventricles (sagittal T1-WI) Figure 41 Dandy-Walker malformation High insertion of the torcula with hypoplasia of the cerebellar vermis (sagittal T1-WI) Diagnostic Imaging in Children 53 Figure 42 Subependymal heterotopia Multiple nodules lining lateral margins of lateral ventricles Isointense to gray matter (transaxial T2-WI) 2 Figure 43 Semilobar...52 Pediatric Neurosurgery 2 Figure 38 Complete absence of the corpus callosum with abnormal parallel configuration of the lateral ventricles (sagittal T1-WI) Figure 39 Chiari I Inferior herniation and “peg-like” configuration of the cerebellar tonsils (sagittal T1-WI) Figure 40 Chiari II Small posterior fossa with inferior herniation... lipoma Tethered cord with intradural T1-hyperintense lipoma along the dorsal upper sacrum Lipoma becomes markedly hypointense on sagittal T2-WI with fat saturation (sagittal T1-WI, and T2-WI with fat saturation) CHAPTER 3 Neurotrauma Nathan R Selden Craniocerebral Trauma Initial Evaluation and Resuscitation Centers that emphasize coordinated, protocol-driven care of pediatric neurotrauma victims, including... Appearance Mass Table 15 Intramedullary spinal masses 60 Pediatric Neurosurgery 56 Rare 57 ~30 % of pediatric intramedullary tumors Metastases ↑ = increased; ↓ = decreased; SI = signal intensity Mass with variable SI and enhancement Syringohydromyelia may be present Figures ~60% of pediatric intramedullary tumors Other Features Associated with von Hippel-Lindau disease Often indistinguishable from astrocytoma,... 15 Continued Diagnostic Imaging 61 2 62 Pediatric Neurosurgery Figure 55 Acute disseminated encephalomyelitis Scattered foci of intramedullary T2 hyperintensity within the cervical and upper thoracic spinal cord (sagittal T2-WI) 2 Figure 56 Astrocytoma of the cervical cord Heterogeneous enhancing T1-hypointense and T2-hyperintense intramedullary mass (sagittal T1-WI with and without contrast) Figure... 61 60 Figures 64 Pediatric Neurosurgery Diagnostic Imaging in Children 65 2 Figure 59 Epidural abscess Large epidural T2-hyperintense (compared to CSF) collection along ventral lumbar spinal canal (sagittal T2-WI with fat saturation) Figure 60 Drop metastases from germinoma Abnormal enhancing intradural and extramedullary nodule in the left thecal sac at the L5-S1 level (sagittal T1-WI with contrast... ventricle, lined with gray matter (coronal T1-WI) Pediatric Neurosurgery Autosomal dominant Caused by mutations in a tumor-suppressor gene on chromosome 17 >90% of cases of neurofibromatosis Café au lait spots Cutaneous neurofibromas Lisch nodules (pigmented hamartomas of the iris) Macrocephaly Kyphoscoliosis Mental retardation Family history Neurofibromatosis type-1 (NF1; Von Recklinghausen’s disease) Figures... Peripherally enhancing, partially cystic, intramedullary mass expanding the upper cervical spinal cord (sagittal T1-WI with contrast, T2-WI) Extradural Intra- or extradural Intradural Epidural hematoma Meningeal cyst (e.g., arachnoid cyst or arachnoid loculation) Perimedullary spinal arteriovenous fistula Neurofibroma: peripheral ↑T2 and central ↓T2 SI; variable enhancement Schwannoma: iso- or hypodense, isointense... neurofibromas Cataracts Family history Type Table 14 Continued 56 Pediatric Neurosurgery Features Most cases sporadic Congenital angiomatosis of face, ocular choroids and leptomeninges Facial angioma or “port-wine stain” Seizures Hemiparesis Glaucoma or buphthalmos Mental retardation von Hippel-Lindau disease (retinocerebellar angiomatosis) Sturge-Weber syndrome (encephalotrigeminal angiomatosis) ↓ = decreased; . T2-WI) Figure 36 . Pineal cyst. Well-defined homogeneous (nonenhancing) T1-hypointense and T2-hyperintense cyst-like mass in the pineal region. (sagittal T1-WI, and transaxial T2-WI) Figure 37 . Pineo- blastoma. the hypothalamic region. (coronal T2-WI, sagittal T1-WI with contrast) Figure 33 . Pituitary adenoma filling the sella and extending into the suprasel- lar space. (coronal and sagittal TI-WI with. intensity 48 Pediatric Neurosurgery 2 Figure 35 . Germinoma. Slightly heterogeneous, mildly enhancing T1-hypointense, T2-hyperintense mass in the pineal region. (transaxial T1-WI with contrast, and T2-WI) Figure