G. Pellicanò

Ascending myelopathy in the early stage of spinal cord injury

A 30-year-old healthy woman was involved in a road traffic accident. She sustained a fracture dislocation of T11/12 with a complete Frankel A paraplegia below T11. She had no associated injuries. High Dose Methylprednisolone was administered according to the NASCIS III protocol (48 h) together with low molecular weight Heparin and gastroprotected medication. Complete transection of the spinal cord and an anterior haematoma from T11 to T12 were confirmed on X rays, CTs and MRI scans. Posterior surgical stabilisation was performed using Isola instrumentation, starting 8 h post injury. Her post surgical period was uneventful except for some episodes of low blood pressure (85/60 mmHg) from which she had no symptoms. On the 12th post operative day, while in the physiotherapy department, she complained of right scapular pain. This occurred every time she was sat up and was associated with paraesthesia of both upper limbs. Two days later she deteriorated neurologically and her level ascended initially to T8 and then to T3. MRI of the spine with and without gadolinium showed spinal cord oedema between C3 and T1. There was no evidence of haemorrhage or syringomyelia. The authors discussed this case making different hypotheses. They are mainly the following: (1) Gradually ascending ischaemia due to a vascular disorder; (2) Double spinal trauma; (3) Ischaemia related to repeated hypotensive episodes; (4) Low grade intramedullary tumour; and (5) Thrombus of the Radicularis Magna artery. The case has been recognised as being very rare and interesting. In the conclusions, the presenting author stresses the importance of adopting MRI-compatible instrumentation for the surgical stabilisation of the spine, and careful monitoring of blood pressure during the acute phase of spinal cord injury. Dr Aito agrees with Mr El Masry about the opportunity of forming a group of clinicians in order to discuss protocols to cope with this devastating complication.

Changes in Aqueductal CSF Stroke Volume in Shunted Patients with Idiopathic Normal-Pressure Hydrocephalus

BACKGROUND AND PURPOSE: Aqueductal CSF stroke volume (ACSV) measured by phase-contrast MR imaging is a tool for selection of surgical patients with idiopathic normal-pressure hydrocephalus (iNPH). The aim of the present study was to investigate whether there is a relationship between clinical outcome and changes in ACSV in patients with iNPH who have been shunted. MATERIALS AND METHODS: Sixty-five shunted patients with iNPH underwent clinical evaluation and ACSV measurements 7–30 days before and 1, 3, 6, and 12 months after surgery. RESULTS: Two patients were excluded from the study for the occurrence of a perioperative complication. In a group of 35 clinically improved patients, the mean preoperative ACSV (157.01 μL) decreased to 18% one month after ventriculoperitoneal shunt (VPS) and ≤49% at 12 months post-VPS. In a group of 15 unimproved patients, the lower mean preoperative ACSV (84.2 μL) decreased to 14.3% one month post-VPS and ≤34% at 12 months post-VPS. In the other 8 improved patients who developed a subdural fluid collection (SDFC), ACSV values decreased by 43%–75% in the 3 months post-VPS. A postoperative ACSV increase was noted in 6 patients with a shunt system malfunction. One patient experienced both SDCF and shunt malfunction. CONCLUSIONS: ACSV decreases in all patients in whom the VPS system works properly, with the rate of ACSV decrease being higher in the patients who show clinical improvement. Postoperative ACSV increase suggests shunt malfunction. A precipitous drop of ACSV values after VPS may be the consequence of increased drainage and herald the occurrence of SDFC.

Spinal Extradural Tumours, Cysts and Tumour-Like Masses:

Spinal tumors and tumor-like masses are traditionally categorized as extradural, intraduralextramedullary or intradural in location: this scheme is useful because it helps to characterize this kind of lesions. Extradural masses occur outside the spinal dura and typically arise from the osseous spine and adjacent soft tissues or directly from epidural space. In the extradural compartment of the spine numerous primary bone tumour scan occur. However, with few exception (e.g. vertebral haemangioma), most ofthe primary bone tumours are unusual, while systemic tumours or vertebral metastases, are far more common. Moreover several benign non-neoplastic tumour-like lesions can cause an extradural mass.

La RM nelle sequele dei traumi cranici

Given the higher sensitivity of MRI and the recent advances in faster imaging techniques the purpose of the study was to obtain MRI findings in 70 patients who had suffered from a head injury with transient consciousness loss or prolonged coma at least 24 months before entering the study. Multiplanar MRI offers invaluable advantages in the identification of the precise location of the sequelae of cranial traumas. In case of hemorrhagic lesions, the information capacity of CT progressively diminishes in relation to the absorption of the edema and bleeding, whereas MRI increases its sensitivity due to the paramagnetic properties of hemoglobin by-products. MRI allows the identification of a larger amount of small lesions, particularly those located at critical sites, as corpus callosum, temporal and frontal tips cortical surface. Using Fluid Attenuated Inversion Recovery (FLAIR) pulse sequences, a better delineation of cortical and subcortical lesions is permitted, with remarkable improvement of sensitivity when compared with conventional Spin-Echo images. Finally, adopting MRI has important implications from a medico-legal standpoint.

Siringomielia post-traumatica: Studio RM e definizione dei meccanismi di formazione e crescita

Lo scopo del nostro lavoro è stato quello di studiare con RM pazienti con siringomielia post-traumatica per identificare, in alcuni di essi, il motivo dell’insorgenza di nuovi sintomi a distanza di tempo dal trauma; in altri, per monitorare nel tempo l’eventuale crescita della cavità prima della comparsa di sintomatologia ed inoltre per verificare il risultato operatorio. Sono stati infine indagati i possibili meccanismi di crescita delle cavità intramidollari post-traumatiche.

Tecniche di angio-RM: Stato dell'arte

MRI is very sensitive to flow effects and they may be exploited to develop non-invasive techniques for imaging of the vascular anatomy. These techniques are referred to as Magnetic Resonance Angiography (MRA). MRA techniques can be classified in two major categories: time-of-flight (TOF) and phase contrast (PC). Both techniques rely on different physical effects; inflow-enhancement and flow-induced phase shift respectively. In both techniques definitive angiographic images are obtained by means of post-processing of data with a Maximum Intensity Projection (MIP) algorithm. TOF MRA can be classified in three major categories: 2D-sequential, 3D-volumetric and multi-slab-3D (MOTSA). To improve vessel-background contrast in TOF MRA, new techniques, such as ramped radiofrequency (rf), pulses across the slab to partially compensate for the progressive saturation of spins (TONE) and magnetization transfer contrast (MTC) have been introduced. In PC MRA complex subtraction of two data sets with a different amount of flow sensitivity produces an image with signal intensities depending on flow velocity. Quantitative information about flow velocity and flux can also be obtained in PC MRA. More recently the use of contrast agents with ultrafast imaging (CE-MRA) has shown significant improvements in the delineation of the vessel lumen.

La RM nelle sequele dei traumi spinali

From January 1990 to April 1997 we retrospectively evaluated 90 patients with MR examinations at our Spine Unit. The following post-traumatic spinal cord lesions were diagnosed: atrophy (47 pts), myelomalacia (40 pts), cysts (14), syrinx (14) and medullary transection with adhesion(4 pts). MR was very useful to identify atrophy more frequently found at the cervical-thoracic level (C6-D3). Myelomalcia was found in a patient with severe vertebral body trauma with chronic compression of the spinal cord. Intramedullary cysts were found in patients with hematomyelia in acute phase and were stable lesions. Post-traumatic syringomyelia is the most important sequela due to the fact that is often correlated with symptoms. MR not only detected the lesion but also identified intramedullary cavities without new neurological symptoms and guided surgery and follow-up. MR is the examination of choice not only for diagnosis of chronic spinal cord lesions but also to evaluate the possibility of surgical treatment.

L'Angio-TC delle biforcazioni carotidee

Computed Tomography (CT) now offers detailed information on the carotid bifurcation with short acquisition times and high spatial resolution. With new spiral acquisition devices it is possible to improve the quality of images and subsequent reconstruction with Multiplanar, Shaded Surface Display and Maximum Intensity Projection algorithms. In patients with atherosclerotic occlusive and stenotic disease CT clearly identifies the site and the type of plaque, distinguishing high density “hard” calcified plaque from soft fibrolipid build up which is hypodense with respect to the contrast enhanced lumen. In case of mixed plaque both components are well displayed as is their arrangement along the vessel wall. The endoluminal surface of the plaque is easily explored, sometimes disclosing small surface ulcerations resulting in emboli. CT is also able to measure the degree of lumen stenosis both applying the NASCET criteria and by calculating the ratio between total vessel area and residual lumen. Finally multiplanar and three-dimensional reconstructions offer a longitudinal view of the vessel and further information on the arrangement and size of the atheroma.

Low-field 2D-time-of-flight MRA of intracranial and cervical blood vessels as a complementary technique in cerebrovscular ischaemic disease

We set out to assess the utility of low-field two-dimensional time-of-flight (2D-TOF) MRA of intracranial and cervical blood vessels in patients with conventional MRI findings of cerebrovascular ischaemic disease. We examined 21 patients with stroke syndromes in the acute and subacute phases. Standard MRI cranial examination (spin-echo T1-, spin-density- and T2-weighted images) was followed by a 2D-TOF MRA of intracranial and cervical blood vessels. In 5 patients, a haemodynamic study of the circle of Willis was obtained by means of selective presaturation bands. Cranial MRI showed brain lesions (occlusive infarct, watershed and multifocal leukoencephalopathy). MRA showed findings consistent with steno-occlusion of the internal carotid artery in 14 patients, the middle cerebral artery in 4 and the posterior cerebral artery in 1. In 2 patients, MRA was negative. In all but 1 patient, there was a correlation between the side of brain lesions and the side and degree of intravascular signal abnormalities. Selective presaturation of individual vessels of the circle of Willis allowed demonstration of collateral supply to the compromised territory in 3 patients.

Radicular Somatosensory Evoked Potentials Recording During Foraminotomy

Among the various cerebral and myeloradicular pathologies in which we use a BASIS EPM for somatosensory evoked potential (SEP) recording, we have given much attention to the study of the cervical radicular compressions.