Role of contrast-enhanced magnetic resonance angiography in spinal dural arteriovenous fistula

Spinal dural arteriovenous fistulae (SDAVF) are the most common vascular malformations of the spine. Although digital subtraction angiography (DSA) remains the standard of reference to diagnose and classify vascular spinal lesions, we investigated the clinical value of contrast-enhanced MR angiography (CE-MRA), equipped with TRICKS sequences, in localizing SDAVF before selective catheter angiography and possible subsequent treatment. We studied 16 consecutive patients suspected of harbouring vascular spinal cord malformations and we tried to determine the level and the side of the arterial feeder to the arteriovenous abnormality. In 12 cases the results were compared with DSA and/or possible post-operative findings. In nine cases CE-MRA correctly depicted the origin of the fistula: in particular one patient was treated surgically only on the basis of MRA results. Thanks to its elevated spatial and temporal resolution, spinal contrast-enhanced MRA using TRICKS sequences proved reliable in detecting and localizing the SDAVF arterial feeders and can be used as a guide to subsequent selective DSA examination.

Quantitative cervical spinal cord 3T proton MR spectroscopy in multiple sclerosis

BACKGROUND AND PURPOSE

Brain proton MR spectroscopy ((1)H-MR spectroscopy) is a useful technique for evaluating neuronal/axonal damage and demyelization in multiple sclerosis (MS). Because MS disability is frequently related to spinal cord lesions, potential markers for MS stage differentiation and severity would require in vivo quantification of spinal integrity. However, few spectroscopy studies have investigated cervical disease due to technical difficulties. The present study used 3T (1)H-MR spectroscopy to measure the main metabolites in cervical spinal cord plaques of a group in patients with relapsing-remitting MS (RRMS) and compared them with metabolite measurements in healthy volunteers.

MATERIALS AND METHODS

A (1)H-MR point-resolved spectroscopy sequence volume of interest was prescribed along the main axis of the cord between C2 and C3 levels on a plaque in a group of 15 patients with RRMS for a total acquisition time of approximately 14 minutes. MR spectroscopy data were analyzed by the user-independent fitting routine LCModel, and relative metabolite concentrations were expressed by the absolute concentration ratios. A Student t test was used to evaluate the difference compared with the healthy metabolite content previously published.

RESULTS

We found a significant decrease of total N-acetylaspartate/choline and an increase in choline/creatine and myo-inositol/creatine content on MS plaques in comparison with healthy cervical spine tissue.

CONCLUSIONS

In vivo (1)H-MR spectroscopy, if confirmed by other similar studies, should be as reliable for clinical studies as it is in brain imaging. Moreover, (1)H-MR spectroscopy allows examination of spinal cord integrity at a biochemical level and may be sensitive to subtle changes occurring during the course of MS disease.

3-Tesla Study of the Spinal Cord White Matter

Spinal cord as soon as brain, can be affected by dysmyelinating and demyelinating diseases, as Multiple Sclerosis (MS), Acute Disseminated Encephalomyelitis (ADEM), Neuromyelis Optica (NMO) and Transverse Myelitis. Investigation of the spinal cord with a high field strength MR system is hampered by the inhomogeneous magnetic field, physiological movements and the small size of the anatomical area. We describe normal and pathological neuroradiological findings in spinal cord white matter and the parameters of optimized sequences for use with the 3T MR systems.

Evolutive study of relapsing-remitting multiple sclerosis with cervical proton magnetic resonance spectroscopy. A case report

We used quantitative proton magnetic resonance spectroscopy ((1)H-MRS) to evaluate mean relative concentrations ratios for NAA, Cr, Cho and mI during the study of cervical spinal cord plaques in a relapsing-remitting multiple sclerosis (RRMS). A cervical spine MR exam was repeated five times on the following days for two months starting from the onset of a relapse phase, using a 3T whole-body system, with the voxel placed along the demyelinazation lesion. The quantification results were compared with the healthy metabolites content. Quantitative cervical spectroscopy is a reliable tool and can offer important metabolic information as already used on the brain to evaluate the severity, progression and pathogenesis of multiple sclerosis.

Massive Peripheral Nerve Hypertrophy in a Patient with Chronic Inflammatory Demyelinating Polyradiculoneuropathy

We describe a male patient with chronic inflammatory demyelinating polyradiculoneuropathy presenting extensive diffuse hypertrophy of the nerve roots of peripheral nerves. Since adolescence the patient has had a slow and progressive mainly distal loss of sensitivity and muscle weakness in all four limbs. He presented with diffuse muscle atrophy with enlarged palpable nerve trunks. Electromyography disclosed impaired sensory and motor responses in the bilateral median nerves and the right ulnar nerve. CSF examination showed elevated protein content, while MR scans depicted extensive hypertrophy of the spinal nerve roots. The patient benefitted from corticosteroid treatment.

Childhood spinal glioblastoma multiforme with intracranial dissemination. A case report

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.

CE-MR Angiography at 3.0 T Magnetic Field in the Study of Spinal Dural Arteriovenous Fistula. Preliminary Results

SUMMARY

We report technical data and results in eight patients studied with spinal contrast-enhanced MR angiography (CE-MRA). We used a 3.0 Tesla device, dedicated phased array coil and time resolved imaging of contrast kinetics (TRICKS) sequences to visualize the feeder vessels in patients with vascular malformations. TRICKS is a method of 3D CE-MRA providing temporal information. Thanks to its high temporal and spatial resolution and high signal/noise ratio the TRICKS optimized sequence at 3.0 T yielded very encouraging results in disclosing the origin of arteriovenous malformations.

3 Tesla MR Study of Cerebellar Medulloblastoma

Medulloblastoma belongs to the group of highly malignant neuroepithelial tumours and is the commonest tumour in childhood (average age nine years) followed by astrocytoma 1. 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.

[Lung base disease after orthotopic liver transplantation. Functional ultrasonography of the diaphragm and correlated alterations]

PURPOSE

To demonstrate the greater accuracy of B- and M-probe ultrasound (US) compared to traditional examinations in the evaluation of diseases of the lung-base, a frequent localisation of pathology in patients undergoing orthotopic liver transplantation (OLT).

MATERIAL AND METHODS

Twenty-one patients, 13 males and 8 females aged 24 to 63, awaiting OLT were examined using the three modalities. B-mode US was performed as a preliminary study to identify the districts of interest and the profile of the diaphragm wall, searching for any related alterations. This was followed by M-mode US, with an approach along the left and right posterior axillary lines during spontaneous and forced maximal expiration, to calculate and document the curve representing diaphragm mobility. All patients were also studied pre- and postoperatively by standard chest X-ray double projections. The parameters evaluated by US were diaphragmatic inspiratory slant and diaphragm range while the standard chest X-ray was used to assess hypoventilation, diaphragm range and pleural effusion.

RESULTS

For each parameter considered we obtained the following results: presence or absence of pleural effusion (sensitivity: 100% with US vs 64% with chest X-ray) and diaphragmatic hypomobility with related hypoventilatory phenomena (sensitivity: 85% with US, with 15% false negatives). In 15 cases the chest X-ray revealed a clear elevation of the diaphragm, a finding supported by US in 11 cases. In 7 cases US showed a reduction in the diaphragm range curve without, however, any radiological evidence of any ventilatory dysfunction of the lung base and/or elevation of the corresponding hemidiaphragm.

CONCLUSION

Our results suggest that radiology, B-mode US and color Doppler US, which are widely used for monitoring OLT patients, can be usefully integrated by M-mode US to evaluate diaphragmatic mobility both pre- and post-operatively. This method is fast, easy to use and widely available.

[Nonobstructive residual mucocele of the cystic duct. Reassessment of complications in our 13 years' experience with liver transplantation]

PURPOSE

We reassessed the incidence of mucocele of the residual cystic duct in our series of orthotopic liver transplantation (OLT) patients.

MATERIAL AND METHODS

We examined a series of 283 liver transplants with end-to-end choledocho-choledocal anastomosis (263 patients, 163 men and 80 women, 24-65 years old), performed at the II Surgical Department of the University of Bologna from May 1986 to April 1999 and subsequently followed-up in our Institute. All patients were examined with gray-scale and color Doppler US and some also underwent CT and CT cholangiography.

RESULTS

An anechoic ovoidal structure just before the portal vein and in proximity of the main bile duct was found in 13 patients. US and CT findings, the latter when available, led us to make a diagnosis of nonobstructive mucocele of the cystic duct. The radiological diagnosis was eventually confirmed by clinical and surgical findings.

DISCUSSION AND CONCLUSIONS

In our series the incidence of this complication was 4.5%, a slightly higher value than those reported in the literature. Cystic duct mucocele cannot be considered an uncommon complication and should thus be more carefully searched for by operators. In our experience this complication never required reoperation for cholestasis.