Fetal Nuerosonogram Professor Hassan Nasrat FRCS, FRCOG The Fetal Medicine Clinic The First Clinic JUCOG January 2013 Sunday, July 28, 13 Microcephaly Holoprosencephaly Head normal or small Chiari Malforma3on ACC Dia Anencephaly Occipital Encephalocele Schizencephaly Schizencephaly Circle of Willis Mallformation Vascular Malforma3ons SOP Pilu Imaging Findings Herniated brain tissue „cyst within the cyst“ Ventriculomegaly 7080% Microcephaly 25% Polyhydramnios Oligohydramnios Encephalocele PF-­‐Fluid-­‐Cyst CAVE: Associated with multiple syndroms ( Meckel- Gruber ) Hydrance halus , T 21 Ventriculomegaly Hemimegalencephaly Arachnoid cyst Hydranecphaly Yong seok et a 2 Sunday, July 28, 13 Congenital CNS Anomalies o Incidence in longtem studies about 1 % o Only minimal identified at birth o Screening Increases The Number Of Referred Cases For Evaluation Of Suspected CNS Anomalies. o The CNS sonographic appearance changes throughout pregnancy Sunday, July 28, 13 Learning Objec3ves ✤ Embryonic development of the CNS in relation to sonographic findings ✤ Standard Sonographic Examination of the CNS ✤ Fetal Neurosonography and the Role of 3 D (systemic approach to examination of the Posterior Fossa) 4 Sunday, July 28, 13 Embryology of the CNS Sunday, July 28, 13 At 5th Week The Cells Destined To Form The Notochord Infiltrate Into The Embryonic Disc. I t I n d u c e s T h e Overlying Embryonic Tissue To Thicken And Ultimately Fold Over And Fuse As The The Fusion Starts In Neural Tube. The Midtrunk Of The E m b r y o A n d Subsequently Extends To The Cranial And Caudal Ends Neural Crest Neural Groove Neural Plate Sunday, July 28, 13 Ectoderm Neural Tube Prosencephalon Mesencephalon Rhombencephalon 7 Sunday, July 28, 13 Three orthogonal images and thick slice of three-dimensional reconstructed image (lower right) of normal brain at 8 the end of 8 weeks of gestation. The development of premature ventricular system is seen. Sunday, July 28, 13 Prosencephalon Mesencephalon Three orthogonal images and thick slice of three-dimensional reconstructed image (lower right) of normal brain at 8 the end of 8 weeks of gestation. The development of premature ventricular system is seen. Sunday, July 28, 13 Normal brain development on the mid-sagittal section between 8 and 12 weeks of gestation). Note the remarkable changing of premature 9 brain appearance. Sunday, July 28, 13 AJR:166, AJR:166, Changing Ultrasound appearance of the The Posterior Fossa throughout gesta3on SONOGRAPHIC February 1996 February 1996 AJR:166, February 1996 ANATOMY SONOGRAPHIC ANATOMY SONOGRAPHIC OF DEVELOPING 433 CEREBELLUM OF DEVELOPING CEREBELLUM ANATOMY OF DEVELOPING CEREBELLUM 433 433 10 C Sunday, CC July 28, 13Fig. C D 13.-Drawings depicting some relevant features D DD of fetal cerebellar development. The vermis develops superiorly to inferiorly. Hypoplasia or developmental arrest results in varying size deficits of the inferior portion, leaving a relatively square defect that communicates with the fourth ventricle and separates the lower cerebellar hemispheres. 11 Sunday, July 28, 13 C D Fig. 13.-Drawings depicting some relevant features of fetal cerebellar development. A, Axial drawing of developing cerebellum at 5 weeks’ gestational age shows that developing cerebellar hemispheres have not yet grown toward midline and thatfourth ventricle is covered only byfourth ventricular roof,which is onlytwo cell layers thickatthis stage of development. B, Sagittal drawing of developing cerebellum at 10 weeks’ gestational age shows small cerebellum located rostrally over fourth ventricle, with caudal fourth ventricle being covered only by thin fourth ventricular roof. C, Sagittal drawing at 16 weeks’ gestational age shows further caudal growth of cerebellum ening 0, of caudal Sagfttal fourth drawing ventricular roof. at 17 weeks’ gestational age shows cerebellum We have shown that the sonognaphic appearance of normal cemebellar development can resemble pathology early in the second trimester. Our findings indicate that the mature relationships of the posterior fossa structures are not established until at least 18 weeks’ gestational age; therefore, the Sunday, July 28, 13 diagnosis prenatal sonographic of Dandy-Walker complex and vermis covering 4. Achinon entire R, Tadmor ten of pregnancy: and vermis over fourth fourth 0. Screening tnansvaginal ventrIcle, teno thic and with thick- ventricle. for fetal anomalies versus transabdominal 1991 1:186-191 during the first tnimesUltra- sonography. sound Obstet Gynecol 5. Nicolaides KH, Azan G, Byrne D, Mansur C, Marks K. Fetal nuchal translucency: ultrasound screening for chromosomal defects in first trimester of pregnancy. BMJ 1992:304:867-869 6. Bronshtein M, Blumenfeld I, Kohn J, Blumenfeld Z. Detection ofcleft lip by early 12 of posteriorB, Next fossa caudal in 13- image to 14-week-old called acquisition in stea identifies fetus. fourth ventricular roof joining cerebellar hemispheres fetus. Vermis A, Vermis is identified between cerebellar hemispheres rostrally (arrow). age of posteriorfossa in (arrow) and separating fourth ventricle and cisterna magna. but not caudally B, Next caudal image identifies fourth ventricular roof joining cerebellar hemispheres fetus. Vermis is identified (arrow) and separating fourth ventricle and cisterna magna. but not caudally at this s Effect of Gesta=onal age (Posterior Fossa) Fig. 7.-Axial Fig. 7.-A and tenor fossa tenor fossa in 16-weekA and A and B, Caudally, thickto enoug thick enough be v and sagittal and (B) sagittal planes axial sagittal sonograms of posterior fossa in 16-week-old fetus fourth ventricular roof is visualized in both planes (arrow) 13 Sunday, July 28, 13 gure 1 Transvaginal scan of a 14-week fetus. (a) Oblique-1 (sagittal) section: the fetus is facing left. The choroid plexus fills the antrum ure Transvaginal scananterior ofaa14-week 14-week fetus.(a) (a) Oblique-1(sagittal) (sagittal) section: the fetusisisfacing facing left.The Thechoroid choroid plexus fills the antrum ure Transvaginal of Oblique-1 section: the left. plexus the antrum the11lateral ventricle. scan The hornsfetus. appear prominent, but are normal; (b) a fetus Frontal-2 (coronal) section through thefills anterior horns the lateral ventricle. The anterior horns appear prominent, but are normal; (b) a Frontal-2 (coronal) section through the anterior horn he lateral ventricle. The anterior horns appear prominent, but are normal; (b) a Frontal-2 (coronal) section through the anterior horns the lateral ventricles. The anterior horns are normal for this gestational age; however, this same sonographic picture at 20 weeks or the lateral ventricles. The anterior horns are normal for this gestational age; however, this same sonographic picture at 20 weeks o he lateral ventricles. The anterior horns are normal for this gestational age; however, this same sonographic picture at 20 weeks or ore is consistent with ventriculomegaly or hydrocephalus re is consistent with ventriculomegaly or hydrocephalus re is consistent with ventriculomegaly or hydrocephalus Effect Of Scanning Level (Posterior Fossa) Higher Still Section gure 2Lower-most Three serial, almost axial (horizontal) views through the posterior section (see insert). The Somewhat Higherfossa. (a) This is the lower-most ure 22appears Three serial, almost axial (horizontal) views through fossa. (a) isisthe section The ermis be open (arrow) communicates the the fourth ventricle through aThis wide (at this gestational age,(see normal) median gure Threeto serial, almost axialand (horizontal) viewswith through theposterior posterior fossa. (a)This thelower-most lower-most section (seeinsert). insert). Th mis appears to be open (arrow) and communicates with the fourth ventricle through a wide (at this gestational age, normal) median perture (foramen of Magendie); (b) somewhat higher, the right and left sides of the cerebellar hemispheres appear closer to each other rmis appears to be open (arrow) and communicates with the fourth ventricle through a wide (at this gestational age, normal) media rture The (foramen of Magendie); (b) higher, right left ofofthe hemispheres totoeach rrow); (c) higher still, noAppears ‘vermian defect’ and the ventricle (4) appears as a discrete entity.‘vermian C,appear cerebellum Vermis To is seen erture (foramen of Magendie); (b)somewhat somewhat higher, thefourth rightand and leftsides sides thecerebellar cerebellar hemispheres appearcloser closer eachother othe No Defect’ The Right And Left Sides row); (c) higher still, no ‘vermian defect’ is seen and the fourth ventricle (4) appears as a discrete entity. C, cerebellum row);Be (c) higher still, (arrow) no ‘vermian And defect’ is seen and the fourth ventricle (4) appears as a discrete entity. C, cerebellum Open Is Seen And The Of The Cerebellar Communicates With Theand theHemispheres its closest anatomic structures, the cavum eduncular cistern (cisterna magna) fourth ventriFourthnamely Ventricle (4) septi Appear anatomic structures, namely the septi duncular cistern magna) the ventripellucidi and the pericallosal artery, follow acavum well-known e. Later, 16thVe postmenstrual this ‘normal’ its closest closest anatomic structures, namely the cavum sep duncular cistern (cisterna thefourth fourth ventri- its F o uafter r t hthe(cisterna nmagna) t r i c land eandweek, Appears As A Closer To Each Other pellucidi and the pericallosal artery, follow a well-known Later, after the 16th postmenstrual week, this ‘normal’ developmental timetable. They artery, do not reach pen space narrows as postmenstrual the growth and development of pellucidi and the pericallosal followa adevelopmenwell-know . Later, after the 16th week, this ‘normal’ Through A Wide Discrete Entity. en space the ofof developmental (arrow); tal stage that timetable. allows forThey sonographic imaging until poste vermis progress, giving rise to and the median aperture developmental timetable. Theydodonot notreach reacha adevelopmendevelopmen en space narrows narrows as as the growth growth and development development vermis progress, giving rise median Magendie) (Figure 2).the Again, thisaperture normal eoramen vermis of progress, giving rise to to the median aperture ramen Magendie) 2). this normal onographic may (Figure be interpreted by those unfamiliar ramen of of finding Magendie) (Figure 2). Again, Again, this normal Sunday, July 28, 13 nographic finding may be interpreted by those unfamiliar tal allows for sonographic imaging until post14 before menstrual weeks 18–19. search for their presence talstage stagethat that allows forTo sonographic imaging until pos menstrual for they reachweeks this 18–19. critical stage in their development would menstrual weeks 18–19.To Tosearch search fortheir theirpresence presencebefore befor they reach this critical stage in their development would Effect of Gesta=onal age (Lateral Ventricles) 15 Sunday, July 28, 13 The fetal cerebellum Pitfalls in diagnosis Hypoplasia Or Dysplasia Should Not Be Diagnosed Prior To 18 Weeks, Before Vermian Development Is Complete. An Abnormally Steep Scanning Angle May Mimic A Prominent Cleft Between The Lower Portions Of The Cerebellar Hemispheres. 16 Sunday, July 28, 13 Conclusion •TheCNS displays remarkable embryological and developmental changes throughout gestation. •Standard Approach of examination and evaluation of the CNS Should Be Followed 17 Sunday, July 28, 13 Standard Sonographic Examination of the FEtal CNS 18 Sunday, July 28, 13 Sunday, July 28, 13 Sonography of the CNS Basic Examination “Neurosongram” Sunday, July 28, 13 Planes of Basic Examina3on Axial Planes Sunday, July 28, 13 Sagibal Planes Axial Planes Sunday, July 28, 13 Axial Planes a: Transventricular Sunday, July 28, 13 Axial Planes a: Transventricular b: Transthalamic Sunday, July 28, 13 Axial Planes a: Transventricular b: Transthalamic C: Transcerebeller Sunday, July 28, 13 The Transventricular plane Sunday, July 28, 13 The Transventricular plane Frontal hones Sunday, July 28, 13 The Transventricular plane Frontal hones Atrium Sunday, July 28, 13 The Transventricular plane Frontal hones Atrium Sunday, July 28, 13 Choroid Plexus The Transventricular plane Cavum Sep3 Pellucidi Frontal hones Atrium Sunday, July 28, 13 Choroid Plexus The Transthalamic Plane Sunday, July 28, 13 The Transthalamic Plane Thalami Sunday, July 28, 13 The Transthalamic Plane Thalami Hyppocamas Gyrus Sunday, July 28, 13 The Transcerebeller plane T T Sunday, July 28, 13 The Transcerebeller plane T T Cavum Sep3 Pellucidi Sunday, July 28, 13 The Transcerebeller plane Frontal hones T T Cavum Sep3 Pellucidi Sunday, July 28, 13 The Transcerebeller plane Cerebellum Frontal hones T T Cavum Sep3 Pellucidi Sunday, July 28, 13 The Transcerebeller plane Cerebellar vermis Cerebellum Frontal hones T T Cavum Sep3 Pellucidi Sunday, July 28, 13 The Transcerebeller plane Cerebellar vermis Cerebellum Frontal hones T T Cavum Sep3 Pellucidi Sunday, July 28, 13 Cistrerna Magna 2-­‐10 mm Sagibal Planes Sunday, July 28, 13 Sagibal Planes A: The Midsagittal Plan Sunday, July 28, 13 Sagibal Planes b: Parasgittal plane A: The Midsagittal Plan Sunday, July 28, 13 Mid SagiGal Plane Corpus Callosum Cavum Sep3 Pellucidi Cerebellum 4th V 27 Sunday, July 28, 13 Mid SagiGal Plane 27 Sunday, July 28, 13 The Corpus Callosum 28 Sunday, July 28, 13 The Corpus Callosum Lateral Ventricles Splenium Corpus Callosum Thalamus hypothalamus Third Ventricle Pituitary Fourth ventricle midbrain 28 Sunday, July 28, 13 Para-­‐SagiGal Plane 29 Sunday, July 28, 13 Basic Examniation Checklist Head + Neck Midline & Falx Cavum septi pellucidi Lateral cerebral ventricls Choroid Plexus Cerebellum Cisterna magna 30 Sunday, July 28, 13 Main Abnormali3es can be Suspected on Basic Planes 31 Sunday, July 28, 13 Holoprosencephaly Microcephaly Head normal or small Chiari Malforma3on ACC Dia Anencephaly Occipital Encephalocele Schizencephaly Schizencephaly Circle of Willis Mallformation Vascular Malforma3ons SOP Pilu Imaging Findings Herniated brain tissue „cyst within the cyst“ Ventriculomegaly 7080% Microcephaly 25% Polyhydramnios Oligohydramnios Encephalocele PF-­‐Fluid-­‐Cyst CAVE: Associated with multiple syndroms ( Meckel- Gruber ) Hydrance halus , T 21 Ventriculomegaly Hemimegalencephaly Arachnoid cyst Hydranecphaly Yong seok et a 32 Sunday, July 28, 13 Holoprosencephaly Microcephaly Head normal or small Chiari Malforma3on ACC Dia Anencephaly Occipital Encephalocele Schizencephaly Schizencephaly Circle of Willis Mallformation Vascular Malforma3ons SOP Pilu Imaging Findings Herniated brain tissue „cyst within the cyst“ Ventriculomegaly 7080% Microcephaly 25% Polyhydramnios Oligohydramnios Encephalocele PF-­‐Fluid-­‐Cyst CAVE: Associated with multiple syndroms ( Meckel- Gruber ) Hydrance halus , T 21 Ventriculomegaly Hemimegalencephaly Arachnoid cyst Hydranecphaly Yong seok et a 32 Sunday, July 28, 13 Holoprosencephaly Microcephaly Head normal or small Chiari Malforma3on ACC Dia Anencephaly Occipital Encephalocele Schizencephaly Schizencephaly Circle of Willis Mallformation Vascular Malforma3ons SOP Pilu Imaging Findings Herniated brain tissue „cyst within the cyst“ Ventriculomegaly 7080% Microcephaly 25% Polyhydramnios Oligohydramnios Encephalocele PF-­‐Fluid-­‐Cyst CAVE: Associated with multiple syndroms ( Meckel- Gruber ) Hydrance halus , T 21 Ventriculomegaly Hemimegalencephaly Arachnoid cyst Hydranecphaly Yong seok et a 32 Sunday, July 28, 13 Holoprosencephaly Microcephaly Head normal or small Chiari Malforma3on ACC Dia Anencephaly Occipital Encephalocele Schizencephaly Schizencephaly Circle of Willis Mallformation Vascular Malforma3ons SOP Pilu Imaging Findings Herniated brain tissue „cyst within the cyst“ Ventriculomegaly 7080% Microcephaly 25% Polyhydramnios Oligohydramnios Encephalocele PF-­‐Fluid-­‐Cyst CAVE: Associated with multiple syndroms ( Meckel- Gruber ) Hydrance halus , T 21 Ventriculomegaly Hemimegalencephaly Arachnoid cyst Hydranecphaly Yong seok et a 32 Sunday, July 28, 13 •Ventriculomegaly (hydrocephalus) •Absent Cavum Septum Pellucidum •Agenesis of the Corpus Callosum •Fluid Collection in the posterior fossa 33 Sunday, July 28, 13 Ventriculomegaly (hydrocephalus) Mild 10 – 15 mm Low Risk mean = 6-­‐8 mm Severe > 15 mm High Risk (< 10 mm is normal). Independent of gesta7onal age Sunday, July 28, 13 Pathogenesis: Ventriculomegaly Lee Lateral Ventricle Right Lateral Ventricle Foramen of Monro Aqueduct of Sylvius 4th Ventricle 3rd Ventricle Cisterna Magna 35 Sunday, July 28, 13 Absent CSP •Square Shaped, Interrupts and Fills The Space Between The Frontal Horns •The CSP: Becomes Visible At 16 Weeks, Obliterate Near Term Sunday, July 28, 13 Absent CSP Cavum Sep3 Pellucidi •Square Shaped, Interrupts and Fills The Space Between The Frontal Horns •The CSP: Becomes Visible At 16 Weeks, Obliterate Near Term Sunday, July 28, 13 Absent CSP A rare finding usually discovered Postnatally in children evaluated for developmental delay. Associated with various brain malformations: agenesis of the corpus callosum Holoprosencephaly. Setpo-­‐optic dysplasia. Secondary to disruptive process: Hydrocephalus, Chiari II malformation, hydranecephaly. Sunday, July 28, 13 Agenesis of the Corpus Callosum 38 Sunday, July 28, 13 21-­‐week Fetus With Par=al Agenesis Of The Corpus Callosum Only The Rostrum (1), Genu (2) And Body (3) Are Visible; The Splenium Is Missing. The Corpus Callosum Is Short Posteriorly And Does Not Seem To Overlay The Quadrigeminal Plate Sunday, July 28, 13 Outcome of fetal ACC Va r i e s b e t we e n co m p l e te l y a sy m p to m a 3 c appearance and severe neurologic problems 50 – 100 % of isolated cases will have normal neurological development at 3-­‐11 years but Poor prognosis with associated anomalies Progressive decline in intellect over the years Most need special educa3on Long-­‐term follow-­‐up of children with prenatally diagnosed agenesis of corpus callosum (ACC) J. H. Stupin et al, USOG, 32, 2008 Sunday, July 28, 13 Fluid Collec3on in the Posterior Fossa 41 Sunday, July 28, 13 Fluid Collec3on in the Posterior Fossa •Megacisterna Magna 41 Sunday, July 28, 13 Fluid Collec3on in the Posterior Fossa •Megacisterna Magna •Blak’s Pouch Cyst 41 Sunday, July 28, 13 Fluid Collec3on in the Posterior Fossa •Megacisterna Magna •D-W Malformation &DW- Variant •Blak’s Pouch Cyst 41 Sunday, July 28, 13 Fluid Collec3on in the Posterior Fossa •Megacisterna Magna •Blak’s Pouch Cyst •D-W Malformation &DW- Variant •Arachnoid Cyst 41 Sunday, July 28, 13 Anomalies Of The Meninges •Megacisterna Magna •Blak’s Pouch Cyst Anomalies Cerebellum •D-W Malformation &DW- Variant •Arachnoid Cyst 42 Sunday, July 28, 13 Mega–Cisterna Magna An Enlargement Of The Cisterna Magna Beyond 10 Mm With Intact Vermis 43 Sunday, July 28, 13 Pathogenesis: Mega Cisterna Magna Lateral Ventricle Third Ventricle Cerebral Aqueduct Choriod Plexus Fourth Ventricle 44 Sunday, July 28, 13 Pathogenesis: Mega Cisterna Magna The Foramina Of Lateral Ventricle Luschka And Magendie Fenestrate Delayed Third Ventricle Cerebral Aqueduct Choriod Plexus Fourth Ventricle 44 Sunday, July 28, 13 Prognosis: • Isolated Cases: (97%-100%) Are Normal. • If Not Isolated: Only 11% Have Normal Outcome. Nonisolated Cases Have VM, Congenital Infection, Or Karyotype Abnormalities. A Large Cisterna Magna Require Careful Search For Other Abnormalities. 45 Sunday, July 28, 13 Blake’s Pouch Cyst 46 Sunday, July 28, 13 Pathogenesis: Blake’s Pouch Cyst Nonfenestration of the foramina of Luschka and Lateral Ventricle Magendie leads to dilatation of the fourth ventricle and and elevation of the vermis away from the brain stem. Third Ventricle Cerebral Aqueduct Choriod Plexus Fourth Ventricle There is no communication between the cyst and the subarachnoid space 47 Sunday, July 28, 13 Pathogenesis: Blake’s Pouch Cyst Nonfenestration of the foramina of Luschka and Lateral Ventricle Magendie leads to dilatation of the fourth ventricle and and elevation of the vermis away from the brain stem. Third Ventricle Cerebral Aqueduct Choriod Plexus Fourth Ventricle There is no communication between the cyst and the subarachnoid space 47 Sunday, July 28, 13 Dandy-Walker Malformation A Spectrum Of Anomalies Of The Posterior Fossa. • Dandy-Walker Malformation: ✦Increase Of The Posterior Fossa, Complete Or Partially Agenesis Of The Cerebellar ✦ Vermis, ✦A Tentorium Elevation • Variant Of Dandy-Walker: ✦Hypoplasia Of The Cerebellar Vermis In Different Degrees With Or Without Increase Of The Posterior Fossa. 48 Sunday, July 28, 13 ctions Dandy-Walker Malformation Elevated tentorium and high position of the torcula Small, rotated, raised, or absent vermis Cystic dilation of the fourth ventricle communicating with a posterior fossa fluid space 49 Sunday, July 28, 13 The Prognosis : Better In Isolated DWS. Karyotype Abnormalities In About 15%. Neonatal Mortality: 12% To 55%. Neonatal Morbidity: •Intelligence Is Normal In About 40% •Borderline In 20% •Subnormal In 40%. 50 Sunday, July 28, 13 Blake’s Pouch Cyst igure 2 2The position ofof thethe torcular Herophili (arrows) is inferred Dandy–Walker Malformation Figure The position torcular Herophili (arrows) is inferre The Torcular Is Found In A Normal The Torcular Is DisplacedIn Higher non ultrasound byby the direction thethe tentorium cerebelli. (a)(a) theth Position, At About The Same Levelofof ultrasound the direction tentorium cerebelli. In Than Usual, Indicating That This As The Site Of Insertion Of The orcular is is found inin a normal position, at at about thethe same level as as torcular found a normal position, about same level Is A Neck Muscles On The Posterior he site ofof insertion ofof thethe neck muscles onon thethe posterior skull; this theSkull site insertion neck muscles posterior skull; 51 thi pouch cyst. In (b) the torcular is displaced higher than isaSunday, aBlake’s Blake’s July 28, 13 pouch cyst. In (b) the torcular is displaced higher than Arachnoid Cysts • Are Benign, Noncommunicating Fluid Collections Within Arachnoid Membranes. • Location: Intracranially And In The Spinal Canal. • Order Of Frequency Are The Sylvian Fissure Or Temporal Fossa, Posterior Fossa, Over The Cerebral Convexity, And Midline Supratentorial, • Most Appear Stable And Require No Surgical Treatment. Occasionally They Interfere With CSF Circulation And Require Decompression. Sunday, July 28, 13 The Differential Diagnosis Depends On The Location. In The Posterior Fossa: DandyWalker Malformation, Inferior Vermian Hypoplasia, Mega–cisterna Magna, And Blake’s Pouch Cysts. Supratentorial Cysts: Cavum Veli Interpositi, Aneurysm Of Vein Of Galen, Hemorrhage, And Cystic Tumors. 53 Sunday, July 28, 13 Prenatal diagnosis and outcome of fetal posterior fossa fluid collections G. GANDOLFI COLLEONI et al, Ultrasound Obstet Gynecol 2012; 39: 625–631 54 Sunday, July 28, 13 105 Fetuses Blake’s Pouch Cyst N = 32 Arachnoid Cyst N=1 Megacisterna Magna N = 27 Cerebellar Hypoplasia N=2 Sonographic diagnoses were accurate in 88% Sunday, July 28, 13 Dandy – Walker Malformation N=26 Vermian Hypoplasia N=17 55 ✦ Isolated Cases Of Blake’s Pouch Cyst And Megacisterna Magna Have An Excellent Prognosis, With A High Probability Of Intrauterine Resolution And Normal Intellectual Development In Almost All Cases. ✦ Dandy – Walker Malformation And Vermian Hypoplasia, Even When They Appear Isolated Antenatally, Are Associated With An Abnormal Outcome In Half Of Cases. 56 Sunday, July 28, 13 Conclusion •Black’s Pouch Cyst, DW Malformation, and Mega-­‐Cisterna Magna Can give Similar Sonographic features. •However the prognosis is greatly varialbe. •Careful Neurosonographic assessment using 3 D or Fetal MRI is often Needed 57 Sunday, July 28, 13 Technical Guideline How do we do it? Practical advice on imaging-based techniques and investigations Three dimensional ultrasound examination of the fetal central nervous system Gianluigi Pilu, Tullio Ghi, Angela Carletti, Maria Segata, Antonella Perolo, Nicola Rizzo From the Department of Obstetrics and Gynecology University of Bologna, Italy Address for correspondence: [email protected] Originally published in Ultrasound Obstet Gynecol 2007; 30: 233–245 Sunday, July 28, 13 3D ultrasound is a data set that contains a large number o f 2 D p l a n e s ( B -­‐ m o d e images). e.g. If the page of a book is one 2D plane, then the book itself is the en3re data set. The 3 D probe acquire the data by moving a B mode transducer within a housing like a hand held Japanese fan . Sunday, July 28, 13 Pyramid Of Volume Informa=on ✴ “Walking” through the volume is similar to leafing through the pages of a book i.e. walking through the various 2D planes that make up the entire volume. ✴ The Volume can be dissected in any plane, to get “Multiplanar Imaging” Sunday, July 28, 13 the acquired volume unlike the defined rectangle shape of a book looks like a pyramid or triangle of volume informa3on with a broad base 3D volumes of the fetal brain obtained from an axial approach: the ‘start’ scan Cavum septi pellucidi midline Originally published in Ultrasound Obstet Gynecol 2007; 30: 233–24561 Sunday, July 28, 13 midline A C Sunday, July 28, 13 B Originally published in Ultrasound Obstet Gynecol 2007; 30: 233–245 midline A C Sunday, July 28, 13 B Originally published in Ultrasound Obstet Gynecol 2007; 30: 233–245 midline A B A and B rotated on Z plane until midline is aligned with C plane C Sunday, July 28, 13 Originally published in Ultrasound Obstet Gynecol 2007; 30: 233–245 A B Corpus callosum + cavum septi pellucidi Cerebellar vermis C Sunday, July 28, 13 Originally published in Ultrasound Obstet Gynecol 2007; 30: 233–245 Acoustic shadow midline Corpus callosum Cavum sep* pellucidi midline Corpus callosum + cavum sep* pellucidi Originally published in Ultrasound Obstet Gynecol 2007; 30: 233–245 Sunday, July 28, 13 64 Angled Insona3on of Posterior Fossa to Visualize brain Stem 4v Brain stem Cerebellar vermis Originally published in Ultrasound Obstet Gynecol 2007; 30: 233–245 Sunday, July 28, 13 65 hemisphere hemisphere tentorium 4v vermis hemisphere hemisphere tentorium vermis vermian fissures 4v Sunday, July 28, 13 Originally published in Ultrasound Obstet Gynecol 2007; 30: 233–245 body atrium Occipital horn Temporal horn Sylvian fissure Originally published in Ultrasound Obstet Gynecol 2007; 30: 233–245 Sunday, July 28, 13 67 68 Sunday, July 28, 13 69 Sunday, July 28, 13 70 Sunday, July 28, 13 71 Sunday, July 28, 13 72 Sunday, July 28, 13 73 Sunday, July 28, 13 Agenesis of the corpus callosum Normal corpus callosum 3v Absent corpus callosum 3v Par3al agenesis 3v Originally published in Ultrasound Obstet Gynecol 2007; 30: 233–245 Sunday, July 28, 13 74 Normal Posterior Fossa At Midgesta=on Axial view SagiGal view Prenatal diagnosis and outcome of fetal posterior fossa fluid Collec=ons Gandolfi Colleoni et al., UOG 2012 Sunday, July 28, 13 Normal Posterior Fossa At Midgesta=on Cavum Sep3 Pellucidi Axial view SagiGal view Prenatal diagnosis and outcome of fetal posterior fossa fluid Collec=ons Gandolfi Colleoni et al., UOG 2012 Sunday, July 28, 13 Normal Posterior Fossa At Midgesta=on Cavum Sep3 Pellucidi Cerebellar vermis Axial view SagiGal view Prenatal diagnosis and outcome of fetal posterior fossa fluid Collec=ons Gandolfi Colleoni et al., UOG 2012 Sunday, July 28, 13 Normal Posterior Fossa At Midgesta=on Cisterna Magna Cavum Sep3 Pellucidi Cerebellar vermis Axial view SagiGal view Prenatal diagnosis and outcome of fetal posterior fossa fluid Collec=ons Gandolfi Colleoni et al., UOG 2012 Sunday, July 28, 13 Normal Posterior Fossa At Midgesta=on Cisterna Magna Cavum Sep3 Pellucidi Cerebellar vermis Tentorium Axial view Cisterna Magna SagiGal view Prenatal diagnosis and outcome of fetal posterior fossa fluid Collec=ons Gandolfi Colleoni et al., UOG 2012 Sunday, July 28, 13 Normal Posterior Fossa At Midgesta=on Cisterna Magna Cavum Sep3 Pellucidi Cerebellar vermis Tentorium Axial view Cisterna Magna SagiGal view Prenatal diagnosis and outcome of fetal posterior fossa fluid Collec=ons Gandolfi Colleoni et al., UOG 2012 Sunday, July 28, 13 Normal Posterior Fossa At Midgesta=on Cisterna Magna Cavum Sep3 Pellucidi Cerebellar vermis Tentorium Axial view Cisterna Magna SagiGal view Prenatal diagnosis and outcome of fetal posterior fossa fluid Collec=ons Gandolfi Colleoni et al., UOG 2012 Sunday, July 28, 13 Normal Posterior Fossa At Midgesta=on Cisterna Magna Cavum Sep3 Pellucidi Cerebellar vermis Tentorium Axial view Cisterna Magna SagiGal view Prenatal diagnosis and outcome of fetal posterior fossa fluid Collec=ons Gandolfi Colleoni et al., UOG 2012 Sunday, July 28, 13 Applica=on of 3 D Imaging in Prenatal diagnosis of Fetal Posterior Fossa Fluid Collec=on 76 Sunday, July 28, 13 Prenatal diagnosis and outcome of fetal posterior fossa fluid Collec=ons Gandolfi Colleoni et al., UOG 2012 Brainstem–vermis and brainstem–tentorium angles allow accurate categorization of fetal upward rotation of cerebellar vermis P. VOLPE*, et al Ultrasound Obstet Gynecol 2012; 39: 632–635 77 Sunday, July 28, 13 Categoriza3on of posterior fossa fluid collec3ons (1) Sunday, July 28, 13 Categoriza3on of posterior fossa fluid collec3ons (1) Findings Blake’s pouch cyst Megacisterna magna Upward rotation of an intact vermis with normal torcular Cisterna magna >10mm with intact and normally positioned cerebellum SagiGal Axial Sunday, July 28, 13 D-­‐W Upward rotation of the vermis (normal or hypoplastic) with elevated torcular Axial View • Transverse Diameter Of The Cerebellum. • The Intactness And Size Of The Vermis. • The Depth Of The Cisterna Magna (10 Mm) Sunday, July 28, 13 79 Cavum Sep3 Pellucidi The Tentorium: Level The Vermis: Shape, Size, Fissures Figure 1 Measurement of brainstem–vermis (BV) and brainstem–tento 80 thisJulycase Sunday, 28, 13 after acquisition of an ultrasound volume starting from an axi Cavum Sep3 Pellucidi Brainstem-tentorium (BT) angle Brainstem-vermis Figure 1 Measurement of brainstem–vermis (BV) and brainstem–tento (BV) angle 81 this case after acquisition of an ultrasound volume starting from an axi Sunday, July 28, 13 1 Measurement of brainstem–vermis and brainstem–tentorium (BT) angles. (a) A median of the fetalis brain is obta Measurement of brainstem–vermis (BV)(BV) and brainstem–tentorium (BT) angles. (a) A(a) median viewview ofview the brain (in Figure 1 Measurement of brainstem–vermis (BV) and brainstem–tentorium (BT) angles. A median of fetal the fetal brainobtained is obtained eter after acquisition of an ultrasound volume starting from an axial view) and the main anatomic landmarks are identified. (b) acquisition of an ultrasound volume volume startingstarting from an axial and the anatomic landmarks are are identified. (b)(b) A line this case after acquisition of an ultrasound from anview) axial view) andmain the main anatomic landmarks identified. A lini angentially to the aspect ofbrain the brain stem is drawn tangentially to ventral contour ofcerebellar the cerebe gentially to the dorsal aspect ofaspect the stem and aand second line isline drawn tangentially to the contour of the cerebellar drawn tangentially todorsal the dorsal of the brain stem anda asecond second line is drawn tangentially toventral thethe ventral contour of the the interposed angle is(1) theisangle; BV angle; theangle BTBT angle between the first line and aline third line tangential totentoriu the te interposed angle (1) angle is(1) the BV the BT (2) is (2) measured between the first line and aand third tangential to the tentorium vermis; the interposed the BV angle; the angle (2)isismeasured measured between the first line a third line tangential to the Measurement Of Brainstem–vermis (BV) Angle (1) And Brainstem–tentorium (BT) In Three Conditions Blake’s Pouch Cyst Cerebellar Vermis Hypoplasi Dandy–Walker Malformation. The Angles Has The Widest Measurement In DA Malformation 82 Figure 2 Measurement Sunday, July 28, 13 of brainstem–vermis (BV) angle (1) and brainstem–tentorium (BT) angle (2) in fetuses with: (a) Blake’s pouch cys Blake’s pouch cyst Dandy–Walker malformation Vermian hypoplasia Dandy–Walker malformation 1212 7 12 23.0 63.5 34.9 63.5 Brainstem–vermis Angle 2.8 17.6 5.4 17.6 60 40 20 0 0 7.0 15.1 32–52 15.1 51–1 45–66 51–112 Brainstem– Tentorium Angle Normal Normal Blake’s pouch Vermian Dandy–Walker cyst hypoplasia malformation Blake’s pouch Vermian Dandy–Walker hypoplasia malformation Figure 3 Box-and-whiskercyst plot of distribution of brainstem–vermis angle in controls and in fetuses with upward rotation of the vermis. Medians by a of linebrainstem–vermis inside each box, Figure 3cerebellar Box-and-whisker plot are of indicated distribution th and 75th percentiles by box limits and 5th and 95th percentiles 25 angle in controls and in fetuses with upward rotation of the by lower and upper bars, respectively. Brainstem–tentorium angle (°) Brainstem–tentorium angle (°) Brainstem–vermis angle (°) Brainstem–vermis angle (°) 20 67.2 7.1 80 80 40 42.2 52.1 67.2 80 80 60 19–26 45–112 24–40 45–112 60 60 40 40 20 20 Normal Blake’s pouch cyst Normal Vermian Dandy–Walker hypoplasia malformation Blake’s pouch Vermian Dandy–Walk cyst hypoplasia malformatio Figure 4 Box-and-whisker plot of distribution of brainstem– tentorium angle in controls and in fetuses with upward rotation of the cerebellar vermis. Medians are indicated by a line inside each Figure 4 Box-and-whisker plot of distribution of brainstem– box, 25th and 75th percentiles by box limits and 5th and 95th tentorium angle inupper controls in fetuses with upward rotation o percentiles by lower and bars,and respectively. Box-and-whisker plot of distribution of Box-and-whisker of cerebellar vermis. Medians are plot indicatedof by a distribution line inside each box, th th th th 25 and 75 percentiles by box limits and 5 and 95 percentiles tentorium angle in controls andinside in each cerebellar vermis. Medians are indicated by a line brainstem–vermis angle in controls and in thebrainstem– by lowerhad andaupper bars, < respectively. th th th BV angle 18◦ and a BT angle < 45◦ . The BV 25 and 75 upward percentilesrotation by box limits andcerebellar 5 and 95th box, fetuses with of the fetuses upward increased rotationinofeach theofcerebellar Table 2 Statistical brainstem–vermis (BV) and angle with was significantly the three percentiles bycomparison lower andofupper bars, respectively. brainstem–tentorium (BT) angles in controls and in fetuses with subgroups of anomalies (Figure 3, Table 2), the angle vermis. Medians arevermis indicated by a line inside vermis. Medians inside ◦ are indicated by a line ◦ upward rotation of the cerebellar had a increasing BV anglewith < 18 and aseverity BT angle 45 . TheThe BV increasing of the<condition. each box, 25thcomparison and 75th percentiles by box limits 2 Statistical of brainstem–vermis (BV) and th percentiles BT box, angle demonstrated a75 similar pattern, angle was significantly increased in each but of there the three each 25th and by was box Table P (Mann–Whitney U-test) brainstem–tentorium (BT) angles in controls and in fetuses with more overlapping among groups3, (Figure 4, 2), Table 2). angle subgroups of anomalies (Figure Table the th th and 5 and 95 percentiles by lower and upper upward*rotation of the cerebellar vermis limits and 5th and 95th percentiles by lower Comparison BV angle BT angle increasing with increasing severity of the condition. The BT and angle a similar pattern, but there was Dupper I Sdemonstrated C U S Sbars, I O N respectively. more overlapping among groups (Figure 4, Table 2). Our results suggest that measurement of the BV angle discriminates Sunday, July 28, 13 accurately posterior fossa fluid collections bars, respectively. Controls vs Blake’s pouch cyst fetuses Controls vs Dandy–Walker Comparison * fetuses < 0.00000005 < 0.000005 P (Mann–Whitney U-test) < 0.00000005 0.00000005 BV < angle BT angle Conclusion Fetal posterior fossa fluid collections associated with upward rotation of the cerebellar vermis range from benign asymptomatic conditions to severe abnormalities associated with neurological impairment. The most frequent of these anomalies, Blake’s pouch cyst, vermian hypoplasia and Dandy– Walker malformation, have a similar sonographic appearance but a very different prognosis 84 Sunday, July 28, 13 In Summary 85 Sunday, July 28, 13 Examination Of The Posterior Fossa And The Cerebellum Axial View Midsagittal Views 86 Sunday, July 28, 13 Prac3cal Approach to the DD of Posterior Fossa Cyst and Cys3c like Lesions Sunday, July 28, 13 Prac3cal Approach to the DD of Posterior Fossa Cyst and Cys3c like Lesions 1. Is the Vermis Present?Is the Vermis intact? Sunday, July 28, 13 Prac3cal Approach to the DD of Posterior Fossa Cyst and Cys3c like Lesions 1. Is the Vermis Present?Is the Vermis intact? 2. Is the Toruclar in a normal posi3on (tentorial Cerebelli)? Sunday, July 28, 13 Prac3cal Approach to the DD of Posterior Fossa Cyst and Cys3c like Lesions 1. Is the Vermis Present?Is the Vermis intact? 2. Is the Toruclar in a normal posi3on (tentorial Cerebelli)? 3. What is the shape of the cerebellar clee? Sunday, July 28, 13 Prac3cal Approach to the DD of Posterior Fossa Cyst and Cys3c like Lesions 1. Is the Vermis Present?Is the Vermis intact? 2. Is the Toruclar in a normal posi3on (tentorial Cerebelli)? 3. What is the shape of the cerebellar clee? 4. Brainstem–vermis (BV) Angle And Brainstem– tentorium (BT) Angle Sunday, July 28, 13 Blacke’s Pouch Cyst Cystegacisterna Magna Ultrasound Obstet Gynecol 2012; 39: 625–631 Published online 14 May 2012 in Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/uog.11071 Prenatal diagnosis and outcome of fetal posterior fossa fluid collections G. GANDOLFI COLLEONI*, E. CONTRO*, A. CARLETTI*, T. GHI*, G. CAMPOBASSO†, G. REMBOUSKOS†, G. VOLPE‡, G. PILU* and P. VOLPE† Vermian Hypoplasia D-­‐W Malforma3on *Department of Obstetrics and Gynecology, University of Bologna, Bologna, Italy; †Fetal Medicine Unit, Di Venere and Sarcone Hospitals, ASL Bari, Bari, Italy; ‡Department of Obstetrics and Gynecology, University of Bari, Bari, Italy K E Y W O R D S: cerebellar anomalies; Dandy–Walker malformation; fetus; megacisterna magna; prenatal diagnosis; ultrasound ABSTRACT Cerebellar ypoplasia Objective To H evaluate the accuracy of fetal imaging in differentiating between diagnoses involving posterior fossa fluid collections and to investigate the postnatal outcome of affected infants. Methods This was a retrospective study of fetuses with posterior fossa fluid collections, carried out between 2001 and 2010 in two referral centers for prenatal diagnosis. All fetuses underwent multiplanar neurosonography. Parents were also offered fetal magnetic resonance imaging (MRI) and karyotyping. Prenatal diagnosis was compared with autopsy or postnatal MRI findings and detailed follow-up was attempted by consultation of medical records and interview with parents and pediatricians. fluid collections from mid gestation. Blake’s pouch cyst and megacisterna magna are risk factors for associated anomalies but when isolated have an excellent prognosis, with a high probability of intrauterine resolution and normal intellectual development in almost all cases. Conversely, Dandy–Walker malformation and vermian hypoplasia, even when they appear isolated antenatally, are associated with an abnormal outcome in half of cases. Copyright 2012 ISUOG. Published by John Wiley & Sons, Ltd. Arachinoid Cyst-­‐Pos Fossa INTRODUCTION 88 Fluid collections in the fetal posterior fossa encompass wideBlake’s spectrum of cyst; different ranging from(e,f) vermian Figure 1 Categorization of posterior fossa fluid collections on ultrasound:a (a,b) pouch (c,d) entities, megacisterna magna; 1 Sunday, July 28, 13 During themalformation; normal variants tocyst severe anomalies hypoplasia; (g,h) Dandy–Walker (i,j)fetuses cerebellar (k,l) arachnoid of the posterior. They fossa.may have Results study period, 105 were hypoplasia; exam- Normal Megacisterna magna Blake’s pouch cyst tentorium Vermian hypoplasia Dandy-­‐Walker malforma3on Originally published in Ultrasound Obstet Gynecol 2007; 30: 233–245 Sunday, July 28, 13 89 Take Home Message Standard and Fetal Neurosonography 90 Sunday, July 28, 13 91 Sunday, July 28, 13 ✦ examina3on of the Fetal CNS should be follow a Standard Protocol 91 Sunday, July 28, 13 ✦ examina3on of the Fetal CNS should be follow a Standard Protocol ✦ Examina3on should include at least three axial planes. 91 Sunday, July 28, 13 ✦ examina3on of the Fetal CNS should be follow a Standard Protocol ✦ Examina3on should include at least three axial planes. ✦ In Each plane the defined landmarks should should be reported as normal or suspicious 91 Sunday, July 28, 13 ✦ examina3on of the Fetal CNS should be follow a Standard Protocol ✦ Examina3on should include at least three axial planes. ✦ In Each plane the defined landmarks should should be reported as normal or suspicious ✦ In the presence of possible abnormali3es pa3ent should be referred for detailed neuorsonogram which include mutli-­‐planner 3 D Sanning. 91 Sunday, July 28, 13 ✦ examina3on of the Fetal CNS should be follow a Standard Protocol ✦ Examina3on should include at least three axial planes. ✦ In Each plane the defined landmarks should should be reported as normal or suspicious ✦ In the presence of possible abnormali3es pa3ent should be referred for detailed neuorsonogram which include mutli-­‐planner 3 D Sanning. ✦ 3 D scanning with mul3planner analysis offers comparable analysis to fetal MRI 91 Sunday, July 28, 13 Thanks 92 Sunday, July 28, 13
