The Neuroradiology Journal

These bioethical reflections review the comparative arguments surrounding specific responsibilities raised by prenatal diagnosis: i) in the face of a risk pregnancy, attested by precise medical documentation, should recourse to prenatal diagnosis figure as a moral obligation or, conversely, is unconditional acceptance of the child incompatible with all prior “quality control”? (parental responsibility) ii) if so, does the final decision rest with the parents, and is a completely neutral attitude by the doctor justified even when the foetus has a complaint for which adequate forms of treatment are available? (medical and professional responsibility) iii) is it right to promote health campaigns introducing compulsory screening for risk categories with the prospect of automatically selecting out foetuses bearing genetic anomalies? (social responsibility). After analysis and discussion of the conflicting arguments over responsible management of prenatal diagnosis, there is a review of the stages through which the diagnostic process passes when a couple go for prenatal diagnosis under the shadow of a risk pregnancy. The aim is to assess the role that may be played by specific ethically-oriented support within the counselling process. For such support to be properly framed, the following suggestions are made: i) Helping towards an aware decision: the consultant should help the couple take a sufficient distance from the outside world and face up to the situation in personal terms. They must be able to decide by criteria they see as their own, worked out as a couple and not absorbed from outside (which mostly means ratified by hearsay). As part of helping the couple to an authentic decision, one notes the concern not to reduce prenatal diagnosis to an automatic stage in a medical routine. Being referred for diagnosis by one's G.P. does not dispense with the need for the parents involved in the first person to size up the position for themselves. ii) Helping to pinpoint the responsibilities that can in all conscience be shouldered: amid the ambivalence that most couples experience, it is important that some outsider should let them know the difficulties that await them, but also the resources they can draw on. Though it is up to the couple to decide whether to terminate or go on with the pregnancy, the process of talking, confiding, reflecting and judging nonetheless gives its own weight of humanity to the decision that will come of it. At the same time it creates the right space in which to identify the real responsibility that one can in all conscience take upon oneself; iii) Creating the conditions for authentic ethical discernment: prenatal diagnosis puts the couple in a paradoxical situation precisely because every pregnancy lives in the hope of a child as its achievement and outcome; the handicap that one learns of through prenatal diagnosis just when the investment is at its ideal height may prove to be something truly intolerable. There are two particular ways of imaging the “blow” of a positive outcome which strongly condition the ethical discernment or even make it impossible: seeing it as an “error”; seeing it as a “horror”. The real alternative to these lies in configuring limitation and impairment as an integral part of our human condition, through which discerning attitude one can come to identify with the handicapped child and recognise the right it has to lead “its own” life.

We describe our experience based on 177 fetal MRI examinations performed in the last ten years, focusing on fetal brain anatomy and fetal brain anomalies, namely oloprosencephaly, agenesis of corpus callosum and Chiari II malformation. Magnetic resonance imaging (MRI) has been proposed as an alternative technique when an expert sonologist requires an in-depth morphological approach. However, there were few literature reports in the 1980s and early 1990s because of both the invasive technique of fetal curarization and later the technical difficulties of MRI “breath holding” sequences. Interest in fetal MRI increased in the late 1990s and many papers appeared after the introduction of MRI ultrafast sequences. Ultrasonography remains the first choice for investigation in pregnancy and technological progress in this diagnostic area with overall 3D ultrasound imaging has led to more accurate indications for fetal MRI in cerebral malformations. The main contribution of fetal MRI imaging is a clear “educational” demonstration of classic malformative patterns of the major pathologies, thanks to spectacular images. We conclude that fetal MRI examination is impressive but substantially unnecessary in the three malformative pathologies considered and in all major malformations. Current use of fetal brain MRI should be reserved for more subtle malformations like neuronal migration disorders, ventriculomegaly of the early second trimester of pregnancy and similar conditions where ultrasound is still ineffective.

Three Tesla imaging of the pediatric brain is feasible without significant SAR limitations and provides improved diagnostic information relative to 1.5 T for MRA, thin section T1 and T2 images, susceptibility scans, and conspicuity of contrast enhancement.

Recent advances in molecular genetics, together with further understanding of cerebral biochemical metabolism affecting the white matter, when taken together with the information provided by MRI and MRS, provide new insights into the inherited white matter diseases.

The neurocutaneous syndromes, also called phakomatoses or hamartomatous syndromes, are a highly variable and heterogenic group of dermatologic, somatic and nervous system disorders. Much attention is paid to these syndromes by neurologists because they are usually accompanied by epilepsy and mental retardation. Dermatological symptomatology is relatively variable, and somatic disturbances are very common, but nervous system disorders, both in clinical and in MRI pictures, are regularly observed. The normal process of neural crest formation in the 4th week of gestation is characterized by a period of rapid proliferation and differentiation of the neuroependymal cells and this process of neuroblast migration is often considered to be the most important developmental period of the brain. This process continues between the 10th and 22nd weeks of gestation and ends with the cellular apoptosis of 30–50% of participating neuroblasts. In some cases, the neuroblasts will not reach their predetermined site within the cerebral cortex and abnormal layers or bands of heterotopias in the subependymal or subcortical spaces may form. These defects in the cortical grey matter manifest themselves as flat cortex (lissencephaly or agyria), pachygyria (macrogyria) or polymicrogyria. The process of neuroblast migration is intertwined with the earlier stages of brain embryogenesis. After four weeks of gestation, in 5–6 mm sized embryos, two branches of the carotid artery are visible, and in 15–16 mm sized embryos two branches of the vertebro-bazilar arterial system are identifiable. The most frequent cause of malformations is genetic chromosomal defects, but similar developmental disturbances are seen in sporadic cases where the developing embryo has been subjected to harmful exogenic influences (i.e. congenital mononucleosis infections, drug dependence, or fetal alcohol syndrome). Here we demonstrate MRI changes in some typical cases of neurocutaneous diseases generally accepted as denoting lissencephaly. Together with lissencephaly some other ventricular (hydrocephalus, mid-line defects) and vascular system abnormalities with variable skin phacomas are observed. In some cases of undiagnosed idiopatic epilepsy, variable skin morphas may be found which serves to emphasize the importance of MRI examination as a diagnostic tool. We frequently observed lissencephaly combined with vascular dysplasias or abnormal ventricular configurations.

We studied a case of middle interhemispheric variant of holoprosencephaly by magnetic resonance. A five-year-old child presented a mild language delay and relational disorders. The etiopathogenesis of the disorder remains controversial, the two main hypotheses being teratogenic and genetic. Magnetic resonance disclosed typical alterations (abnormal midline connection of cerebral hemispheres in the posterior frontal and parietal regions, partial agenesis of corpus callosum, absence of septum pellucidum) which allowed differential diagnosis from the other types of holoprosencephaly, namely the more typical alobar, semilobar and lobar variants.

CT and MR imaging have been used to diagnose polymicrogyria and determine the topological involvement of bilateral frontal, perisylvian, parietal or occipital cortices. We present CT and MR appearances of bilateral asymmetrical frontal and parietal perisylvian polymicrogyria in an eighteen year-old-girl.

‘Double cortex’ is characterized by the presence of a well-defined and well-marginated layer of neurons that lie in the white matter in a location in which their migration to the cerebral cortex has been prematurely arrested. Here, we report a case where band heterotopia was seen in all the lobes of brain.

Hypothalamic or central diabetes insipidus (HD or CDI) is a heterogeneous condition characterized by polydipsia and polyuria due to deficient arginine vasopressin (AVP) synthesis from the supraoptic and paraventricular nuclei of the hypothalamus and/or secretion from the neurohypophysis which have been stored as a complex with neurophysin (NP). Over one third of CDI cases are classified as idiopathic. Absence of the physiological neurohypophyseal hyperintense signal or bright spot on sagittal T1-weighted magnetic resonance imaging (MRI) is a common feature of all cases of CDI. The finding of a thickened infundibulum or pituitary stalk (or both), although not specific, suggests the presence of an infiltrative disease. We investigated the clinical presentation, morphologic characteristics of the pituitary region on MRI and the size of the pituitary stalk over time in two young girls who both later developed another hormone deficiency.

Joubert syndrome was first described in 1969. It is a rare inherited disorder demonstrating one of the developmental defects of the cerebellar vermis. The main clinical signs of the syndome include developmental delay, hypotonia, ataxia, abnormal ocular movements and abnormal respiratory pattern of alternating episodic tachypnea-hyperpnea and apnea. Radiological findings comprise a midline cerebellar cleft in place of the vermis and a characteristic shape of the fourth ventricule. Associated supratentorial abnormalities such as callosal dysgenesis have been infrequently reported in patients with Joubert syndrome This report describes the clinical and neuroradiological findings of a rare patient presenting Joubert syndrome associated with total corpus callosum agenesis.

The craniosynostoses are serious abnormalities of infancy and childhood. The term craniosynostosis indicates a cranial or craniofacial dysmorphism characterized by skull growth disorder due to premature fusion of one or more sutures. It is a common clinical problem requiring the attention of many specialists. The suspicion is usually clinical, based on a cranial deformity. The diagnosis has always been almost exclusively radiological, due to the introduction of three-dimensional reconstruction techniques with Computed Tomography (3D-CT), including especially the Shaded Surface Display (SSD) and Volume Rendering (VR) algorithms. We examined 26 patients in our department with complex craniosynostosis of different types over a period of four years. Considering the data in the literature we analyze the role of 3D-CT and the results of our comparison between the two reconstruction methods in the diagnosis and management of craniosynostoses.

Neck lesions are not uncommon in children and typically present with localised swelling. The neuroradiologist's goal is the diagnosis of cervical lesions as a concomitant pathological finding, especially in cases with intraspinal spread. Neck lesions can be classified in terms of etiology as congenital, inflammatory or neoplastic, but this division is not the best suited to a radiological approach. A more useful diagnostic indicator is the location of the lesion with a further classification based on its radiological hallmarks. An assessment of age distribution is also important for a correct diagnosis.

Ischaemic stroke accounts for 80% of cerebrovascular disease. It is the third commonest cause of death, the second cause of dementia and the primary cause of disability. The widespread availability of CT scanning, the speed of examination and its low cost make CT the gold standard for early diagnosis of stroke before the mechanisms of cell swelling are triggered heralding irreversible neuronal damage. CT scanning allows morphological assessment of brain parenchyma demonstrating or excluding any bleeding and direct or indirect signs of ischaemia. It also allows perfusion imaging to display the cerebral territory at risk. Our study aimed to devise a dynamic CT perfusion imaging technique for use on an ordinary spiral CT system to be combined with morphological study and head and neck CT angiography to disclose the cause of the stroke correlated to clinical findings. Eighty patients with transient and permanent clinical forms of acute ischaemic stroke were referred to our institution within 0.5 to eight hours after clinical onset of symptoms. All patients underwent standard CT scan followed by CT perfusion imaging, intracranial CT angiography, neck CT angiography and brain CT scan after contrast administration. Each patient received a 40 ml bolus of iodate contrast agent for each examination for a total of 120 ml at a concentration of 300 mg/ml. CT perfusion imaging yielded a graph obtained over a ROI centred on the lentiform nuclei showing the peak time (PT) equal to the mean transit time (MTT) and dependent on cerebral blood flow (CBF). The graphic profiles of perfusion correlated to clinical findings and intra and extracranial CT angiography MIP reconstructions demonstrated the etiopathogenesis of stroke, the vascular territory affected and the prognosis. Combined with morphological study of brain parenchyma, CT angiography and clinical findings, CT perfusion graphs offer an immediate diagnosis of hyperacute ischaemic stroke allowing prompt therapeutic decisions to improve the prognosis.

Magnetic Resonance Spectroscopy (MRS) is a complement to Magnetic Resonance Imaging (MRI) in the characterization of intracranial lesions. Its role in the workup of space-occupying brain lesions continues to evolve. In this pictorial essay we demonstrate the important complementary role of MRS to conventional MRI in the diagnosis of brain tumors and tumour like lesions.

Capillary telangiectasia is one of four forms of cerebral vascular malformations consisting of an area of dilated capillaries like a small petechial patch on the brain surface. The lesions are located mainly in the pons and cerebellum. We describe a case of diffuse capillary telangiectasia of the brain in a patient presenting with epilepsy who underwent morphological and function investigation using a 3T MR system.

Cysticercosis is a common parasitic disease in the tropical countries caused by Taenia solium. The diagnosis of cysticercosis is based, primarily, on typical imaging characteristics of CT scan or magnetic resonance (MR) scan, and clinical features. There are so many reports of cysticercosis in the literature involving various isolated body parts. We herewith report a unique case with imaging evidence of cysticercosis in brain, orbit and all skeletal muscles.

We evaluated the efficiency of MR spectroscopy compared with conventional MR imaging in 14 patients with clinical and/or electrophysiologic signs of spinal cord compression. Cervical spinal cord was evaluated for the presence of abnormal signal intensity on T1 and T2 weighted images. MR spectroscopy was performed at the level of spinal cord compression seen on conventional MR images. Clinical and/or electrophysiological studies were also obtained to confirm the presence of a suspected spinal cord compression for these areas. MR spectroscopy was also performed at a normal site of spinal cord without any clinical and/or electrophysiological finding of compression and without any sign of compression on conventional MR images. MR spectroscopy findings of suspected areas were compared with the normal areas for each patient. Twenty levels of cervical spinal cord with both clinical and/or electrophysiological and conventional MR signs of compression were evaluated with MR spectroscopy. MR spectroscopy was also performed at the normal areas of the cervical spinal cord selected adjacent to the level of compression as vascularity and metabolism of cervical spinal cord significantly change between different levels. All patients except one had a decrease in N-acetylaspartate level at the suspected areas compared to the normal areas without any sign or suspicion of compression. Creatine levels were increased in 14 suspected area but decreased in six. Choline levels were decreased in 12 and increased in eight levels. Lactate levels were increased at eight levels and decreased in 12 levels. MR spectroscopy of the spinal cord can yield results supporting both clinical and electrophysiological evaluation. MR spectroscopy of the spinal cord at the level of compression observed on conventional MR images can support neuronal loss and disruption of axonal integrity.

Little is known about the imaging findings of solid variant of aneurysmal cyst which is a rare entity. We found reports of 13 cases located in the spine but none of these lesions were located in the sacrum. Here we describe the plain x-ray, CT and MRI findings and one year follow-up of a solid variant of aneurysmal bone cyst located in the sacrum.

Nerve injury represents a major cause of disability. In the peripheral nervous system nerves have the capacity to regrow, but within weeks after injury it is impossible to clarify whether proper regeneration is under way, or fails. In the present experimental study we report on a novel tool to assess nerve outgrowth in vivo. After systemic application, the novel gadolinium-based magnetic resonance (MR) contrast agent Gadofluorine M (Gf) selectively accumulated and persisted in nerve fibres undergoing Wallerian degeneration giving rise to bright contrast on T1-weighted MR images. Gf enhancement on MRI was present already at 48 hours within the entire nerve segments undergoing Wallerian degeneration, and subsequently disappeared from proximal to distal parts in parallel to regrowth of nerve fibres. Most importantly, Gf enhancement persisted in non-regenerating, permanently transected nerves. Our novel Gf-based MRI methodology holds promise for clinical use to bridge the diagnostic gap between nerve injury and completed nerve regeneration, and to determine the necessity for neurolysis and engraftment if spontaneous regeneration fails.