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Primary spinal cord tumors in children are uncommon and account for approximately 5% of all pediatric central nervous system tumors. Intracranial metastases from primary spinal cord tumors have rarely been reported. Spinal cord glioblastoma in children mainly involves the thoracic region, whereas involvement of the medullaris conus with intracranial dissemination has been described in six cases. This paper describes a pediatric case of thoracic glioblastoma multiforme with intracranial dissemination in the early stage of the clinical course and discuss the clinical and neuroradiological manifestations, the possible patterns of dissemination and finally to consider the therapeutic implications.

Medulloblastoma belongs to the group of highly malignant neuroepithelial tumours and is the commonest tumour in childhood (average age nine years) followed by astrocytoma1. Medulloblastoma usually arises in the posterior fossa, namely the cerebellar vermis, and more seldom in the fourth ventricle, supratentorium and spinal cord. We describe the 3 Tesla magnetic resonance (MR) features of a medulloblastoma located in the right cerebellar hemisphere adhering to the tentorium in a 16-year-old male.

Medulloblastoma belongs to the group of highly malignant neuroepithelial tumours and is the commonest tumour in childhood (12–25 %)1, but is rare in adults (0.4–1%) of all primary brain tumours)1,2. Medulloblastomas usually arise in the posterior fossa and spread readily throughout the CSF, although 10–30% of patients develop extracentral nervous system metastases 2. We describe a 30-year-old woman presenting bone metastases from medulloblastoma located predominantly in the spine.

MR angiography5,17is traditionally divided into “non-contrast enhanced” (NCE MRA) and “contrast-enhanced” (CE MRA) techniques. Contrast-enhanced techniques were initially developed to solve some of the problems encountered with non-contrast-enhanced methods, namely the long examination times, pulsatile flow artefacts, saturation when the mean blood flow is slow or when the imaging slice is parallel to the vessel, the characteristic problems of time of flight (TOF) acquisitions, and the need to define a priori beforehand the velocity sensitivity for phase contrast (PC) acquisitions. Currently used contrast-enhanced techniques 7,8,15,18are based on the acquisition of 3D gradient-echo sequences synchronized at the first passage of contrast medium by different strategies (detection of a test bolus injection, automated triggering, fluoroscopic imaging). Basically, contrast medium is administered to counteract saturation induced by slow blood flow or flow directed parallel to the imaging slice. Contrast medium serves to obtain a “static” image of vascular structures with acquisitions times ranging from a few seconds to 1–2 minutes. To avoid venous contamination, different methods have been used to collect data (centric-approach, elliptical-centric phase encoding order, etc.) in an attempt to record first the information relating to low spatial frequencies (contrast data) with respect to high spatial frequencies (detail and contour data).

The growing demand for brain MR scans in recent years has led to long waiting lists and indiscriminate referral with respect to the clinical need for imaging and appropriateness criteria for MR scanning. To overcome this problem, the Bologna Public Health Service in conjunction with S. Orsola-Malpighi Hospital devised an experimental project instituting a radiological assessment prior to booking MR scans, implemented on 1stNovember 2003. The assessment is carried out by doctors in the Radiology and neuroradiology units to establish whether referral for MR scan is appropriate and to draw up a priority scale for access to MR diagnosis. If MR investigation is deemed inappropriate, the project provides for an alternative procedure or specialist clinical examination. The patient is admitted to the charge of the service and followed throughout the diagnostic work-up, i.e. the doctor undertaking the assessment will prescribe a possible specialist clinical consultation or other radiological procedures, generally CT scans performed by the same Radiology or Neuroradiology unit. We report on neuroradiological assessment of referrals for brain MR scans on behalf of the Public Health Service and carried out at the Neuroradiology Unit in Bellaria Hospital, Bologna. From 1stNovember to 31stJuly 2004, 2659 assessments were undertaken. Of these 2163 were approved for MR scanning whereas 496 referrals were modified, mostly into CT scans and some patients were referred for otorhinolaringology, endocrinology or neurology specialist consultation. To assess the impact of this “filter”, we compared a sample period of six months from 1stFebruary 2003 to 31stJuly 2003 before the radiological assessment project had been implemented with a period of the same length the following year. We found that the number of negative MR scans was halved after the project had been implemented (from 24.49% in 2003 to 12.18% in 2004), showing that in addition to shortening waiting lists for MR scans, there has been a sharp rise in the number of appropriate scans.

A General Electric 3 Tesla Signa Excite system was installed in the Neuroradiology Unit of Bellaria Hospital, Bologna in February 2004. In line with current legislation, we designed a clinical research project to assess the practical impact of the new device on the investigation of brain tumours, the pituitary gland, rare neurological diseases, epilepsy, multiple sclerosis and Parkinson's disease. We describe our preliminary anecdotal findings in the study of brain tumours and the potential impact of 3 T imaging on the preparation and management of neurosurgical candidates. One decisive result to emerge is that the greater awareness of the risks and difficulties entailed in surgical resection help the neurosurgeon establish a more clear-cut relationship with patients on seeking their informed consent. By understanding and accepting the risks involved, we hope to curb the increasing number of legal disputes caused by surgical complications.

Demonstration and accurate localisation of pituitary microadenomas in the adenohypophysis are essential to institute appropriate medical management and aid surgical planning, especially when an endoscopic procedure is envisaged. Given the features of pituitary microadenomas, ideally, high spatial and temporal resolution is required for neuroradiological investigation. There is a consensus in the literature that MR scanning is the method of choice for pituitary imaging and dynamic studies offer greater sensitivity in identifying pituitary microadenomas. However, the spatial resolution and limited number of slices acquired constitute major drawbacks using 1.5 T MR devices. A 3 Tesla Signa Excite MR system (GE Medical Systems) was recently installed in the Neuroradiology Unit of Bellaria Hospital, Bologna. The new device was tested specifically for the study of pituitary microadenomas using an FSE dynamic sequence allowing the acquisition of nine slices (slice thickness 2.5 mm) over the pituitary gland with high spatial resolution in a few seconds. This sequence, repeated six times after gadolinium administration through an injector, displays the gradual enhancement of the adenohypophysis and any microadenomas present in the gland. As the microadenoma uptake of gadolinium is lower than the adenohypophysis uptake, the possible microadenoma presence becomes appreciable only in some of the six sequences as a negative image with respect to the normal parenchyma. Pituitary microadenomas undetected in previous scans using a 1.5 T system were disclosed by this imaging technique with highly accurate morphological localisation.

Intramedullary abscesses are uncommon with a prevalent incidence in childhood and adolescence. Prognosis is not always favourable. Management entails a combined surgical and medical approach with long-term drug therapy. We describe a patient with rapidly progressive hemiparesis and MR findings of an undefined intramedullary expanding lesion in the cervical spine. Rapid evolution of clinical symptoms, and brain MR disclosing meningitis suggested an abscess, subsequently confirmed by histological analysis.

Nella Sindrome di Down sono di frequente riscontro malformazioni della giunzione cranio-cervicale.Gli autori descrivono un raro caso, riscontrato accidentalmente, di malformazione complessa della cerniera studiata con TC ad alta risoluzione.