NEONATAL BRAIN Study Guide With Complete Detailed Answers.

SONOGRAPHIC TECHNIQUE for Neonatal Brain - correct answer 1. most brain sonographic examinations are performed through the anterior fontanelle in both the coronal and the sagittal planes 2. the posterior fossa is evaluated through the posterior and mastoid fontanelles 3. The foramen magnum approach may be useful when evaluating the upper spinal canal, as in patients with a Chiari malformation. Newborn skull - correct answer lobes of the brain - correct answer folds of the meningies - correct answer falx cerebri in ultrasound - correct answer tentorium cerebelli - correct answer caudothalamic notch - correct answer why need to evaluate posterior and mastoid fontanelle? - correct answer extremely important in the evaluation of cerebellar hemorrhage or posterior fossa anomalies, The anterior fontanelle remains open until - correct answer approximately 2 years of age but is suitable for scanning only until about 12 to 14 months. Coronal Brain Scans: Normal Structures MIDLINE STRUCTURES - correct answer Interhemispheric fissure Cingulate sulcus Corpus callosum Cavum septi pellucidi Cavum vergae (when present) Third ventricle Fourth ventricle Brainstem Vermis of cerebellum Coronal Brain Scans: Normal Structures PARAMEDIAN STRUCTURES - correct answer Frontal lobe Parietal lobe Occipital lobe Frontal horn of lateral ventricle Body of lateral ventricle Temporal horn of lateral ventricle Trigone of lateral ventricle Choroid plexus Glomus of choroid plexus Caudate nucleus Internal capsule Thalamus Lentiform nucleus Tentorium cerebelli Cerebellar hemisphere Sylvian fissure Cisterna magna Coronal Brain Scans - anterior to posterior - correct answer A. The most anterior image - Visualization of the anterior cranial fossa is obtained, including the frontal lobes of the cerebral cortex with the orbits deep to the floor of the skull base. B. the *frontal horns* of the lateral ventricles, midline C. Moving laterally from the midline, D. Progressing farther posteriorly to the level above the midbrain E. the cerebellum. F. Most posterior A. The most anterior image - correct answer - the frontal lobes - the orbits Coronal Brain Scans B. the *frontal horns* of the lateral ventricles - Midline - correct answer - the *frontal horns* of the lateral ventricles appear as symmetrical, anechoic, comma-shaped structures with the hypoechoic caudate heads within the concave lateral border - Structures visualized from superior to inferior in the *midline* include the interhemispheric fissure, cingulate sulcus, genu and anterior body of the corpus callosum, and septum pellucidum between the ventricles. Coronal Brain Scans C. Moving laterally from the midline - correct answer - the *caudate nucleus* is separated from the putamen by the internal capsule. - Lateral to the putamen, the *sylvian fissure* is echogenic because it contains the middle cerebral artery (MCA). - The sylvian fissure separates the frontal from the temporal lobe. - Inferiorly, the *internal carotid arteries* bifurcate to form the echogenic anterior cerebral artery and MCA Coronal Brain Scans - D. Progressing farther posteriorly to the level above the midbrain - correct answer - the *body of the lateral ventricles*, on either side of the cavum septi pellucidi . - Below this, the *thalami* lie on either side of the third ventricle, which is usually too thin to visualize in normal infants. - Deep to the thalami, the *brainstem* begins to be visualized. - Lateral to the midline, the thalami are separated from the *lentiform nuclei* (caudate and putamen) by the internal capsule. - Lateral to the lentiform nuclei is the deep white matter region of brain called the centrum semiovale. - the sylvian fissures Coronal Brain Scans - E. the cerebellum. - correct answer - The body of the lateral ventricles becomes somewhat more rounded as the size of the caudate nucleus decreases once posterior to the foramen of Monro - the body of the corpus callosum is deep to the cingulate sulcus, and the third ventricle is located between the anterior portions of the thalami - choroid plexus - deep to the thalami, the tentorium covering the cerebellum - the vermis - temporal horns of the lateral ventricles may be seen lateral and inferior to the thalami (only seen in hydrocephalus) - the trigone or atrium of the lateral ventricles and occipital horns - extensive echogenic glomus of the choroid plexus - corpus callosum deep to the cingulate sulcus—is the splenium - cerebellum is separated from the occipital cortex by the tentorium cerebelli. Coronal Brain Scans - F. The most posterior - correct answer - occipital lobe cortex - posterior to the cerebellum why the globus of choroid plexus is asymmetrical? - correct answer the globus of CP tends to be bigger on the side of head facing up. which window used to scan neonatal brain - correct answer anterior fontanelle posterior fontanelle mastoid fontanelle Sagittal Imaging neonatal brain - correct answer - Midline - Rt lateral - Lt lateral Sagittal Imaging neonatal brain Midline - correct answer - the interhemispheric fissure by recognition of the curving line of the corpus callosum above the cystic cavum septi pellucidi and cavum vergae. - Below the cavum lies the choroid plexus in the roof of the third ventricle. If there is third ventricular enlargement, the massa intermedia will be outlined by CSF and the aqueduct of Sylvius may be visualized. - The fourth ventricle is identified as a notch in the anterior surface of the highly echogenic cerebellar vermis - cingulate sulcus In this view ML sagital scanning, the size of the cerebellar vermis has been used to assess - correct answer gestational age. However, the degree of sulcal development is the most reliable method for gestational age based on established pathologic standards. how to visualize the entire lateral ventricle ? - correct answer angle 10 degrees from ML, the anterior portion of the sector is directed more medially and the posterior portion more laterally, what is the structure around the lateral ventricle? - correct answer Above the lateral ventricle is the cerebral cortex, and below it is the cerebellar hemisphere. what is the most common site of germinal matrix hemorrhage (GMH) in the subependymal region of the ventricle? - correct answer The caudothalamic groove at the junction of these two structures what is the first sulcus to form? - correct answer sulvian fissure, best seen on coronalcoronal narrow echogenic fissure filled with MCA branches when cingulate sulcus forms? - correct answer by week 28, a simple linear cingulate sulcus superior and parallel to the corpus callosum are seen More pronounced lateral angulation sagitally - correct answer - temporal lobes where the MCA branches extend toward the ventricle - peritrigonal blush in the parietal lobe just posterior and superior to the ventricular trigones B. Posterior Fontanelle Imaging - correct answer - lies in the midline at the junction of the lambdoid and sagittal sutures - it is open only until about 3 months of age Posterior Fontanelle Imaging very useful to - correct answer - evaluate the occipital horns for the diagnosis of intraventricular hemorrhage (IVH) - extremely useful for detecting dependently layering clot and clot attached to the choroid plexus bcoz The *occipital horn* does not contain choroid plexus and should be completely anechoic. measurement of the subarachnoid space on a magnified view of the brain can be done from? - correct answer the triangular sagittal sinus to the surface of the cortex subarachnoid space is normally how much in 95% of preterm infants before 36 weeks' gestation - correct answer less than 3.5 mm