XII Congresso Nazionale AINR di Neuroradiologia Pediatrica • Presentazione
P
resentation Dear Friends and Colleagues It is my great honour and pleasure to welcome you to the XII Italian Pediatric Neuroradiology Congress. I can say that to meet you all here in Milan, for this event, is for me a real emotion and the opportunity of a personal growth. So, thank you all for having attended and contributed to the success of this meeting. Together with the scientific committee, our effort in deciding the scientific program was made with the purpose to investigate some topics that have engaged us in the recent years, in particular the normal brain development, the genetic aspects of some brain malformations and the new therapeutic perspective for the metabolic diseases, such as the gene therapy. These issues seem to us of great interest and relevance, thanks to the rapid improvement of the recent clinical applications from the basic research. Other topics will be discussed, such as the broad spectrum of dysimmune encephalitis with a clinical perspective. Furthermore a whole session is devoted to the eye movement disorders, including normal developmental anatomy of ocular motor nerves and their inborn and acquired pathological conditions, a wide range of unfamiliar pathologies during the developmental age. The congress will be preceded by a short course concerning two topics. The first deals with the embriology and the normal and pathological conditions of the craniovertebral junction. The development of this region is important for understanding the genesis of the numerous congenital malformations in this area. The second topic is dedicated to functional MRI in pediatric population. This technique has become a critical research tool for evaluating both normal and abnormal functional brain development and its clinical use is becoming more common in children. Attention to the methodological issues and continued investigations in this area are expected to result in further progress. Furthermore there will be a “challenging case” discussion session, becoming an appreciated tradition in our pediatric neuroradiology meetings. We tried to deal with all these issues in a multi-disciplinary approach, to enrich our knowledge in a broader and more comprehensive way. In this regard, I wish to acknowledge, with appreciation, all the speakers, experienced neuroradiologists and eminent experts from related disciplines. Finally, I believe that, in the internet addicted world, the true meaning of the Congress is the chance to meet together, the opportunity of an exchange of views and constructive discussions, with the effort to better face the difficulties of our daily work, so challenging in dealing with our young patients and, for this reason, so full involving. The image chosen for the Congress wish to convey this idea: the flight of the child over Milan, the busy city but also the multicultural town, is the ability to make you free from constraints, realizing your goal with the power of a constructive passion. Again, thank you all for being here and a warm welcome Cristina Baldoli Presidente del XII Congresso Nazionale AINR di Neuroradiologia Pediatrica
520
Giovedì 2
ottobre
The Neuroradiology Journal 27: 531-536, 2014
www.centauro.it
Centro Congressi San Raffaele - 9.00-13.00
CORSO BITEMATICO La cerniera craniospinale Moderatori: Alberto Beltramello, Giovanna Weber
2
9.40-10.10
Craniovertebral Junction in Chiari I Malformation, Down Syndrome, Achondroplasia and Mucopolysaccharidoses Luisa Chiapparini Milano, Italy
The most important syndromes involving the craniovertebral junction include: Chiari I malformation, Down Syndrome, Achondroplasia and Mucopolysaccharidoses. Chiari I malformation is a heterogeneous entity characterized by impaired cerebral spinal fluid (CSF) circulation at the level of the foramen magnum due to cerebellar tonsillar ectopia. Craniovertebral junction anomalies (basilar invagination, platybasia, odontoid process retroflexion, third occipital condyle, abnormal clival-cervical angle) usually cause ventral cervicomedullary compression, contributing, together with the posterior compression that Chiari malformation causes, to the reduction of the space for the neuroaxis at the level of the bulbospinal junction. The more symptomatic clinical presentation frequently accompany the more severe inferior hindbrain herniation (Chiari 1.5), and have led to derivation of the term complex Chiari malformation to describe these patients with Chiari 1 malformation with complex features. Bone malformations of the craniocervical junction occur in about 50% of the patients with Chiari I malformation, although the frequency ranges from 45 to 60%, depending on the series. Klippel-Feil anomaly, or fusion of the atlas to the occipital may also be present. Down syndrome, or trisomy 21, is the most frequent of the chromosomal disorders and is frequently complicated by atlanto-occipital instability (AOI) and atlanto-axial instability (AAI). The prevalence of AAI in children with Down syndrome has been estimated at 9–30%, while the prevalence of AOI has been reported to be much higher, approximately 61%. The most commonly noted osseous abnormalities include persistent synchondroses, posterior C1 rachischisis, and os odontoideum. This suggests that CVJ instability in children with Down syndrome may be secondary to a combination of ligamentous laxity and associated osseous anomalies. Atlanto-axial instability and potential spinal cord compression is assessed by measurement of the neural canal width, on plain radiographs, and the caliber of the subarachnoid space, on MR examinations. The need for followup radiographic evaluation remains controversial, as the natural evolution of AAI is unclear: some investigators have reported decreasing prevalence of AAI with advancing age, others have reported contrary findings. Achondroplasia is the most common form of human dwarfism, affecting more than 250 000 individuals world-
wide. More than 95% of patients have the same point mutation in the gene for fibroblast growth factor receptor 3 (FGFR3) and more than 80% of these are new mutations. The mutation, which causes gain of FGFR3 function, affects many tissues, most strikingly the cartilaginous growth plate in the growing skeleton, leading to a variety of manifestations and complications. The radiographic abnormalities involve regions in which the growth and development occur primarily through enchondral ossification. Therefore, in the skull, the facial bones, skull base, and foramen magnum are underdeveloped, while the calvarium is normal. The constricted foramen magnum has a characteristic tear drop configuration with obliteration of the surrounding subarachnoid space resulting in compromise of the cervico-medullary junction (CMJ). Other abnormalities include odontoid dysplasia, basiocciput hypoplasia, decrease in the basal angle, and thickening of the posterior rim of the foramen magnum. Mucopolysaccharidoses (MPS) are inherited lysosomal storage disorders caused by deficiency of enzymes required for degradation of glycosaminoglycans. Abnormalities at the CVJ are a major cause of morbidity and mortality in certain MPS, especially Morquio (type IV) and Hurler (type I) varieties. These include a hypoplastic/dysplastic odontoid process, ligamentous instability, soft-tissue thickening around the dens, and compression of the cord by the posterior atlas arch. All of these lead to compromise of the spinal canal at the C1–C2 level. The odontoid abnormality can vary from complete aplasia to varying degrees of triangular configuration, loss in vertical height, and a broad-based odontoid tip. The soft-tissue mass around the dens is typically hypointense or isointense on T1-weighted and hypointense on T2-weighted MR image; the exact composition of the soft-tissue mass remains unclear, although non-ossified fibrocartilage is prominet. The odontoid hypoplasia and associated softtissue thickening have been shown to reverse after bone marrow transplantation. 3
10.10-10.30
Craniovertebral junction (CVJ) Trauma Carla Carollo, Radiodiagnostica Istituto Oncologico Veneto - Padova
Pediatric cervical spine injuries (CSIs) are rare. They are usually the result of high-speed and impact injuries, such as those caused by a motor vehicle accident or by falling from a considerable height. Spine fractures in children represent 1-3% of all pediatric fractures. The pediatric spinal column differs from the adult spine in many ways, and the mechanism of injury varies with age. Three age
531
Giovedì 2 ottobre 2014 - Centro Congressi San Raffaele
groups must be considered:
P
resentation Dear Friends and Colleagues It is my great honour and pleasure to welcome you to the XII Italian Pediatric Neuroradiology Congress. I can say that to meet you all here in Milan, for this event, is for me a real emotion and the opportunity of a personal growth. So, thank you all for having attended and contributed to the success of this meeting. Together with the scientific committee, our effort in deciding the scientific program was made with the purpose to investigate some topics that have engaged us in the recent years, in particular the normal brain development, the genetic aspects of some brain malformations and the new therapeutic perspective for the metabolic diseases, such as the gene therapy. These issues seem to us of great interest and relevance, thanks to the rapid improvement of the recent clinical applications from the basic research. Other topics will be discussed, such as the broad spectrum of dysimmune encephalitis with a clinical perspective. Furthermore a whole session is devoted to the eye movement disorders, including normal developmental anatomy of ocular motor nerves and their inborn and acquired pathological conditions, a wide range of unfamiliar pathologies during the developmental age. The congress will be preceded by a short course concerning two topics. The first deals with the embriology and the normal and pathological conditions of the craniovertebral junction. The development of this region is important for understanding the genesis of the numerous congenital malformations in this area. The second topic is dedicated to functional MRI in pediatric population. This technique has become a critical research tool for evaluating both normal and abnormal functional brain development and its clinical use is becoming more common in children. Attention to the methodological issues and continued investigations in this area are expected to result in further progress. Furthermore there will be a “challenging case” discussion session, becoming an appreciated tradition in our pediatric neuroradiology meetings. We tried to deal with all these issues in a multi-disciplinary approach, to enrich our knowledge in a broader and more comprehensive way. In this regard, I wish to acknowledge, with appreciation, all the speakers, experienced neuroradiologists and eminent experts from related disciplines. Finally, I believe that, in the internet addicted world, the true meaning of the Congress is the chance to meet together, the opportunity of an exchange of views and constructive discussions, with the effort to better face the difficulties of our daily work, so challenging in dealing with our young patients and, for this reason, so full involving. The image chosen for the Congress wish to convey this idea: the flight of the child over Milan, the busy city but also the multicultural town, is the ability to make you free from constraints, realizing your goal with the power of a constructive passion. Again, thank you all for being here and a warm welcome Cristina Baldoli Presidente del XII Congresso Nazionale AINR di Neuroradiologia Pediatrica
520
Giovedì 2
ottobre
The Neuroradiology Journal 27: 531-536, 2014
www.centauro.it
Centro Congressi San Raffaele - 9.00-13.00
CORSO BITEMATICO La cerniera craniospinale Moderatori: Alberto Beltramello, Giovanna Weber
2
9.40-10.10
Craniovertebral Junction in Chiari I Malformation, Down Syndrome, Achondroplasia and Mucopolysaccharidoses Luisa Chiapparini Milano, Italy
The most important syndromes involving the craniovertebral junction include: Chiari I malformation, Down Syndrome, Achondroplasia and Mucopolysaccharidoses. Chiari I malformation is a heterogeneous entity characterized by impaired cerebral spinal fluid (CSF) circulation at the level of the foramen magnum due to cerebellar tonsillar ectopia. Craniovertebral junction anomalies (basilar invagination, platybasia, odontoid process retroflexion, third occipital condyle, abnormal clival-cervical angle) usually cause ventral cervicomedullary compression, contributing, together with the posterior compression that Chiari malformation causes, to the reduction of the space for the neuroaxis at the level of the bulbospinal junction. The more symptomatic clinical presentation frequently accompany the more severe inferior hindbrain herniation (Chiari 1.5), and have led to derivation of the term complex Chiari malformation to describe these patients with Chiari 1 malformation with complex features. Bone malformations of the craniocervical junction occur in about 50% of the patients with Chiari I malformation, although the frequency ranges from 45 to 60%, depending on the series. Klippel-Feil anomaly, or fusion of the atlas to the occipital may also be present. Down syndrome, or trisomy 21, is the most frequent of the chromosomal disorders and is frequently complicated by atlanto-occipital instability (AOI) and atlanto-axial instability (AAI). The prevalence of AAI in children with Down syndrome has been estimated at 9–30%, while the prevalence of AOI has been reported to be much higher, approximately 61%. The most commonly noted osseous abnormalities include persistent synchondroses, posterior C1 rachischisis, and os odontoideum. This suggests that CVJ instability in children with Down syndrome may be secondary to a combination of ligamentous laxity and associated osseous anomalies. Atlanto-axial instability and potential spinal cord compression is assessed by measurement of the neural canal width, on plain radiographs, and the caliber of the subarachnoid space, on MR examinations. The need for followup radiographic evaluation remains controversial, as the natural evolution of AAI is unclear: some investigators have reported decreasing prevalence of AAI with advancing age, others have reported contrary findings. Achondroplasia is the most common form of human dwarfism, affecting more than 250 000 individuals world-
wide. More than 95% of patients have the same point mutation in the gene for fibroblast growth factor receptor 3 (FGFR3) and more than 80% of these are new mutations. The mutation, which causes gain of FGFR3 function, affects many tissues, most strikingly the cartilaginous growth plate in the growing skeleton, leading to a variety of manifestations and complications. The radiographic abnormalities involve regions in which the growth and development occur primarily through enchondral ossification. Therefore, in the skull, the facial bones, skull base, and foramen magnum are underdeveloped, while the calvarium is normal. The constricted foramen magnum has a characteristic tear drop configuration with obliteration of the surrounding subarachnoid space resulting in compromise of the cervico-medullary junction (CMJ). Other abnormalities include odontoid dysplasia, basiocciput hypoplasia, decrease in the basal angle, and thickening of the posterior rim of the foramen magnum. Mucopolysaccharidoses (MPS) are inherited lysosomal storage disorders caused by deficiency of enzymes required for degradation of glycosaminoglycans. Abnormalities at the CVJ are a major cause of morbidity and mortality in certain MPS, especially Morquio (type IV) and Hurler (type I) varieties. These include a hypoplastic/dysplastic odontoid process, ligamentous instability, soft-tissue thickening around the dens, and compression of the cord by the posterior atlas arch. All of these lead to compromise of the spinal canal at the C1–C2 level. The odontoid abnormality can vary from complete aplasia to varying degrees of triangular configuration, loss in vertical height, and a broad-based odontoid tip. The soft-tissue mass around the dens is typically hypointense or isointense on T1-weighted and hypointense on T2-weighted MR image; the exact composition of the soft-tissue mass remains unclear, although non-ossified fibrocartilage is prominet. The odontoid hypoplasia and associated softtissue thickening have been shown to reverse after bone marrow transplantation. 3
10.10-10.30
Craniovertebral junction (CVJ) Trauma Carla Carollo, Radiodiagnostica Istituto Oncologico Veneto - Padova
Pediatric cervical spine injuries (CSIs) are rare. They are usually the result of high-speed and impact injuries, such as those caused by a motor vehicle accident or by falling from a considerable height. Spine fractures in children represent 1-3% of all pediatric fractures. The pediatric spinal column differs from the adult spine in many ways, and the mechanism of injury varies with age. Three age
531
Giovedì 2 ottobre 2014 - Centro Congressi San Raffaele
groups must be considered:
