Neonatal cranial us from A to Z

0 %
100 %
Information about Neonatal cranial us from A to Z
Health & Medicine

Published on February 23, 2014

Author: Bahnassy


DR/Ahmed Bahnassy Consultant radiologist PSMMC

Safe  Bedside- compatible  Reliable  Early imaging  Serial imaging: Brain maturation Evolution of lesions  Inexpensive  Suitable for screening 

Exclude/demonstrate cerebral pathology  Assess timing of injury  Assess neurological prognosis  Help make decisions on continuation of neonatal intensive care  Optimise treatment and support 

Embryology  At the end of the 4th week after conception, the cranial end of the neural tube differentiates into 3 primary brain vesicles  Prosencephalon (Forebrain)  Diencephalon    Thalmus Hypothalmus Posterior Pituitary  Telencephalon  Cerebral hemispheres  Cortex & Medullary Center  Corpus Striatum  Olfactory System  Mesencephalon (midbrain)  Cerebral Aqueduct  Superior and inferior colliculi (quadrigeminal body)  Rhombencephalon (hindbrain)  Myelencephalon  Closed part of medulla oblongata  Metencephalon  Pons  Cerebellum  3rd, 4th, and lateral ventricles  Choroid Plexus

Anatomy of the Neonatal Brain Cerebrum  2 Hemispheres (Gray and White Matter)  Lobes of the Brain  Frontal  Parietal  Occipital  Temporal  Gyrus and Sulcus  Gyrus: convulutions of the brain surface causing infolding of the cortex  Sulcus: Groove or depression separating gyri.

Anatomy of the Neonatal Brain Cerebrum  Fissures  Interhemispheric  Area of Falx Cerebri  Sylvian  Most lateral aspect of brain  Location of middle cerebral artery  Quadrigeminal  Posterior and inferior from the cavum vergae  Vein of Galen posterior to fissure Falx Cerebri  Fibrous structure separating the 2 cerebral hemispheres  Tentorium Cerebelli  “V” shaped echogenic extension of the falx cerebri separating the cerebrum and the cerebellum 

Cerebrum  Basal Ganglia  collection of gray matter  Caudate Nucleus & Lentiform Nucleus  Largest basal ganglia  Relay station between the thalmus and cerebral cortex  Germinal Matrix includes periventricular tissue and caudate nucleus  Thalmus  2 ovoid brain structures  Located on either side of the 3 rd ventricle superior to the brainstem  Connects through middle of the 3rd ventricle through massa intermedia  Hypothalmus  “Floor” of 3rd Ventricle  Pituitary Gland is connected to the hypothalmus by the infundibulum

Anatomy of the Neonatal Brain  Meninges  Dura Mater  Arachnoid  Pia Mater  Cerebral Spinal Fluid (CSF)  Surrounds and protects brain and spinal cord.  40% formed by ventricles, 60% extracellular fluid from circulation.

Ventricular System  Lateral Ventricles: Largest of the CSF cavities.  Frontal Horn  Body  Occipital Horn  Temporal Horn  Trigone “Atrium”  Foramen of Monro  3rd Ventricle  Aqueduct of Sylvius  4th Ventricle  Foramen of Luschka  Foramen of Megendie  Cisterns  Cisterna Magna  Spaces at the base of the skull where the arachnoid is widely separated from the pia mater.

Anatomy of the Neonatal Brain Cavum Septum Pellucidum    Choroid Plexus Corpus Callosum  Broad band of connective fibers between cerebral hemispheres.  The “roof” of the lateral ventricles. Cavum Septum Pellucidum  Thin, triangular space filled with CSF  Lies between the anterior horn of the lateral ventricles.  “Floor” of the corpus callosum Choroid Plexus  Mass of specialized cells that regulate IV pressure by secretion/absorption of CSF  Within atrium of the lateral ventricles

Anatomy of the Neonatal Brain Brain Stem  Midbrain  Pons  Medulla Oblongata

Anatomy of the Neonatal Brain Cerebellum  Posterior cranial fossa  2 Hemispheres connected by Vermis  3 Pairs of Nerve Tracts  Superior Cerebellar Peduncles  Middle Cerebellar Peduncles  Inferior Cerebellar Peduncles

Cerebrovascular System  Internal Cerebral Arteries  Vertebral Arteries  Circle of Willis  Middle Cerebral Artery  Longest branch in Circle of Willis that provides 80% of blood to the cerebral hemispheres

Anatomy of the Neonatal Skull  Fontanelles (“Soft Spots”)  Spaces between bones of the skull

Function and Physiology  Cerebellum  Controls Skeletal Muscle Movement  Cerebral Hemispheres  Frontal  Voluntary muscles, speech, emotions, personality, morality, and intellect  Parietal  Pain, temperature, and spatial ability  Occipital  Vision  Temporal  Auditory and Olfactory

Indications for Sonographic Exam  Cranial abnormality found on pre-natal sonogram  Increasing head circumference with or without       increasing intracranial pressure Acquired or Congenital inflammatory disease Prematurity Diagnosis of hypoxia, hypertension, hypercapnia, hypernaturemia, acidosis, pneumothorax, asphyxia, apnea, seizures, coagulation defects, patent ductus arteriosus, or elevated blood pressure History of birth trauma or surgery Suctioning of infant Genetic syndromes and malformations

Sonographic Technique  What anatomy do you scan?  Supratentorial Compartment  Both cerebral hemispheres  Basal Ganglia  Lateral & 3rd Ventricle  Interhemispheric fissure  Subarachnoid space  Views  Coronal  Modified Coronal (anterior fontanelle)  Sagittal (anterior fontanelle)  Parasagittal (anterior fontanelle)  Infratentorial Compartment  Cerebellum  Brain Stem  4th Ventricle  Basal Cisterns  Views     Coronal (mastoid fontanelle and occipitotemporal area) Modified Coronal Sagittal Parasagittal (with increased focal depth & decreased frequency)

Transucers : 5–7.5–10 MHz  Appropriately sized  Standard examination: use 7.5–8 MHz  Tiny infant and/or superficial structures: use additional higher frequency (10 MHz)  Large infant, thick hair, and/or deep structures: use additional lower frequency (5 MHz) 

Anterior Fontanel The Standard view window Temporal Supplementary view window Posterior Fontanel Supplementary view window Mastoid Fontanel Supplementary view window

 Coronal Views (at least 6 standard planes)

 Sagittal Views (at least 5 standard planes)

1. Interhemispheric fissure 2. Frontal lobe 3. Skull 4. Orbit 5. Frontal horn of lateral ventricle 6. Caudate nucleus 7. Basal ganglia 8. Temporal lobe 9. Sylvian fissure 10. Corpus callosum 11. Cavum septum pellucidum 12. Third ventricle 13. Cingulate sulcus 14. Body of lateral ventricle 15. Choroid plexus (*: plexus in third ventricle) 16. Thalamus 17. Hippocampal fissure 18. Aqueduct of Sylvius 19. Brain stem 20. Parietal lobe 21. Trigone of lateral ventricle 22. Cerebellum (a: hemispheres; b: vermis) 23. Tentorium 24. Mesencephalon 25. Occipital lobe 26. Parieto-occipital fissure 27. Calcarine fissure 28. Pons 29. Medulla oblongata 30. Fourth ventricle 31. Cisterna magna 32. Cisterna quadrigemina 33. Interpeduncular fossa 34. Fornix 35. Internal capsule 36. Occipital horn of lateral ventricle 37. Insula 38. Falx 39. Straight sinus (sinus rectus) 40. Temporal horn of lateral ventricle 41. Circle of Willis 42. Prepontine cistern

Questions to be answered during exam

Doppler uses  Typical transcranial Doppler with imaging scan and recording from middle cerebral artery (MCA).  Doppler image shows circle of Willis.  A = anterior cerebral artery  M = middle cerebral artery  P = posterior cerebral artery  RI = resistive index  Demonstrates  Decreased blood flow/ischemia/infarction  Vascular abnormalities  Cerebral Edema  Hydrocephalus  Intracranial Tumors  Near-field structures

Middle Cerebral Artery

Carotid Siphon - Genu

Anterior Cerebral Artery

Posterior Cerebral Artery – P1

Ophthalmic Artery

Basilar Artery

BLOOD FLOW VELOCITY • Changes in flow velocity occur when: • There is a change in vessel caliber • There is a change in volume flow

should we do doppler study vein of galen aneurysm cyst=doppler

Chiari Malformation  Downward displacement of the cerebellar tonsils and the medulla through the foramen magnum.  Arnold-Chiari malformation shows a small displaced cerebellum, absence of the cisterna magna, malposition of the fourth ventricle, absence of the septum pellucidum, and widening of the third ventricle  Commonly related to meningomyelocele

Chiari Malformation  Sonographic Features  Small posterior fossa  Small, displaced Cerebellum  Possible Myelomeningocele  Widened 3rd Ventricle  Cerebellum herniated through enlarged foramen magnum  4th ventricle elongated  Posterior horns enlarged  Cavum Septum pellucidum absent  Interhemispheric Fissure widened  Tentorium low and hypoplastic

Holoprosencephaly  Common large central ventricle because prosencephalon failed to cleave into separate cerebral hemispheres.  Alobar Holoprosencephaly (Most Severe)  Fused thalami anteriorly to a fused choroid plexus  Single midline ventricle  No falx cerebrum, corpus callosum, interhemispheric fissure, or 3rd ventricle  Semilobar Holoprosencephaly  Single ventricle  Presents with portions of the falx and interhemispheric fissure  Thalmi partially separated  3rd Ventricle is rudimentary  Mild facial anomalies  Lobar Holoprosencephaly (Least Severe)  Near complete separation of hemipsheres; only anterior horns fused  Full development of falx and interhemispheric fissure

Holoprosencephaly Alobar Holoprosencephaly Semilobar Holoprosencephaly

Dandy-Walker Malformation  Congenital anomaly of the roof of the 4th ventricle with occlusion of the aqueduct of Sylvius and foramina of Magendie and Luschka  A huge 4th ventricle cyst occupies the area where the cerebellum usually lies with secondary dilation of the 3rd ventricle; absent cerebellar vermis

Dandy-Walker Malformation

Agenesis of the Corpus Callosum  Complete or partial absence of the connection tissue between cerebral hemispheres  Narrow frontal horns  Marked separation of lateral ventricles  Widening of occipital horns and 3rd Ventricle  “Vampire Wings”

Agenesis of the Corpus Callosum

Ventriculmegaly  Enlargement of the ventricles without increased head circumference  Communicating  Non-communicating  Resut of cerebral atrophy  Sonographic Findings  Ventricles greater than normal size first noted in the trigone and occipital horn areas  Visualization of the 3rd and possibly 4th ventricles  Choroid plexus appears to “dangle” within the ventricular trium  Thinned brain mantle in case of cerebral atrophy

Hydrocephalus   Enlargement of ventricles with increased head circumference  Communicating  Non-communicating Sonographic Findings  Blunted lateral angles of enlarged lateral ventricles  Possible intrahemispheric fissure rupture  Thinned brain mantle  Aqueductal Stenosis  Most common cause of congenital hydrocephalus  Aqueduct of Sylvius is narrowed or is a small channel with blind ends; occasionally caused by extrinsic lesions posterior to the brain stem  Sonographic Findings  Widening of lateral and 3rd ventricles  Normal 4th ventricle

Hydrancephaly  Occlusion of internal carotid arteries resulting in necrosis of cerebral hemispheres  Absence of both cerebral hemispheres with presence of the falx, thalmus, cerebellum, brain stem, and postions of the occipital and temporal lobes  Sonographic findings  Fluid filled cranial vault  Intact cerebellum and midbrain

Cephalocele  Herniation of a portion of the neural tube through a defect in the skull  Sonographic Findings  Sac/pouch containing brain tissue and/or CSF and meninges  Lateral Ventricle Enlargement

Subarachnoid Cysts  Cysts lined with arachnoid tissue and containing CSF  Causes  Entrapment during embryogenesis  Residual subdural hematoma  Fluid extravasation sectondary to meningeal tear or ventricular rupture

Hemorrhagic Pathology  Subependymal-Intraventricular Hemorrhage (SEH-IVH)  Caused by capillary bleeding in the germinal matrix  Most frequent location is the thalamic-caudate groove  Continued subependymal (SEH) bleeding pushes into the ventricular cavity (IVH) & continues to follow CSF pathways causing obstruction  Treatment: Ventriculoperitoneal Shunt  Since 70% of hemorrhages are asymptomatic, it is necessary to scan babies routinely  Small IVH’s may not be seen from the anterior fontanelle because blood tends to settle out in the posterior horns  Risk Factors  Pre term infants  Less than 1500 grams birth weight

Hemorrhagic Pathology  Grades  Based on the extension of the hemorrhage  Ventricular measurement  Mild dilation: 3-10 mm  Moderate dilation: 11-14 mm  Large dilation: greater than 14mm  Grade I  Without ventricular enlargement  Grade II  Minimal ventricular enlargement  Grade III  Moderate or large ventricular enlargement  Grade IV  Intraparenchymal hemorrhage

Hemorrhagic Pathology  Grade I

Hemorrhagic Pathology  Grade II

Hemorrhagic Pathology  Grade III

Hemorrhagic Pathology  Grade IV

Intraparenchymal Hemorrhage  Brain parenchyma destroyed  Originally considered an extension of IVH, but may actually be a primary infarction of the periventricular and subcortical white matter with destruction of the lateral wall of the ventricle.  Sonographic Finding  Zones of increased echogenicity in white matter adjacent to lateral ventricles

Intracerebellar Hemorrhage  Types  Primary  Venous Infarction  Traumatic Laceration  Extension from IVH  Sonographic Findings  Areas of increased echogenicity within cerebellar parenchyma  Coronal views through mastoid fontanelle may be essential to differentiate from large IVH in the cisterna magna

Epidural Hemorrhages and Subdural Collections  Best diagnosed with CT because the lesions are located peripherally along the surface of the brain.

Ischemic-Hypoxic Lesions  Hypoxia: Lack of adequate oxygen to the brain  Ischemia: lack of adequate blood flow to the brain  Types  Selective neuronal necrosis  Status marmoratus  Parasagittal cerebral injury  Periventricular leukomalacia (PVL), white matter necrosis (WMN), or cerebral edema  Focal brain lesions (occurs when lesions are distributed within large arteries)  Sonographic Findings  Areas of increased echogenicity in subcortical and deep white matter in the basal ganglia

Ischemic-Hypoxic Lesions Periventricular Leukomalacia (PVL) or White Matter Necrosis (WMN)  Most important cause of abnormal neurodevelopment in preterm infants  Early chronic stage  Multiple cavities develop in necrotic white matter adjacent to frontal horns  Middle chronic Stage  Cavities resolve and leave gliotic scars and diffuse cerebral atrophy  Increased Echogenicity  Late chronic stage  Echolucencies develop in the echolucent lesions corresponding to the cavitary lesions in the white matter (cysts)

PVL or WMN 1 2 4 3

Brain Infections  Common infections referred to by TORCH  T: Toxoplasma Gondii  O: Other (Syphilis)  R: Rubella Virus  C: Cytomegalovirus  H: Herpes Simplex Type 2  Consequences  Mortality  Mental Retardation  Developmental Delay

Ependymitis and Ventriculitis  Ependymitis  Irritation from hemorrhage within the ventricle  Occurs earlier than ventriculitis  Sonographic Features  Thickened, hypoechoic ependyma (epithelial lining of the ventricles)  Ventriculitis  Common complication of purulent meningitis  Sonographic Findings  Thin septations extending from the walls of the lateral ventricles.

Add a comment

Related presentations

Related pages

Copy of ASUM- Neonatal Cranial Ultrasound - Prezi

Neonatal Cranial Ultrasound Ms. Assema Lalzad, Senior Sonographer, Department of Medical Imaging, St. Francis Xavier Cabrini Hospital; Mercy Hospital for ...
Read more

Neonatal Cranial Ultrasound Standard Views

... Contact Us | Careers ... Neonatal cerebral ultrasound. Cambridge University Press (1997). ... Coronal Views.
Read more

Neonatal Cranial Sonography: Modern Strategies and ...

neonatal cranial sonography: modern strategies and applications june 2007 diagnostic imaging: continuing medical education 2 (af), posterior fontanelle (pf ...
Read more

Does fetal growth restriction lead to increased brain ...

Does fetal growth restriction lead to increased brain injury as detected by neonatal cranial ultrasound in premature ... Yahya Z(1), Sasi A(1), Jenkin ...
Read more

The Radiology Assistant : Neonatal Brain US

Neonatal Brain US; Pediatric Chest CT 1; Pediatric Chest CT 2; Newsletter. February 2016; More. ANBI; ... This deficiency of neonatal cranial US is ...
Read more

Neonatal cranial ultrasound interpretation: a clinical audit

forming cranial US on neonatal units in two regions of the United Kingdom. Design All neonatal and special care baby units where
Read more