Application of diffusion tensor imaging (DTI) and MR-tractography in the evaluation of peripheral nerve tumours: state of the art and review of the literature.

Peripheral nerves can be affected by a variety of benign and malignant tumour and tumour-like lesions. Besides clinical evaluation and electrophysiologic studies, MRI is the imaging modality of choice for the assessment of these soft tissue tumours. Conventional MR sequences, however, can fail to assess the histologic features of the lesions. Moreover, the precise topographical relationship between the peripheral nerve and the tumor must be delineated preoperatively for complete tumour resection minimizing nerve damage. Using Diffusion tensor imaging (DTI) and tractography, it is possible to obtain functional information on tumour and nerve structures, allowing the assess anatomy, function and biological features. In this article, we review the technical aspects and clinical application of DTI for the evaluation of peripheral nerve tumours.

Coronary computed tomography angiography in the evaluation of intermediate risk asymptomatic individuals.

Cardiovascular disease is still one of the main causes of death and an early identification of coronary artery disease (CAD) remains the primary step in clinical management of patients with cardiovascular risk factor. Coronary computed tomography angiography (CCTA) has shown high sensitivity in CAD detection and could be helpful as screening method. The purpose of this study was to assess the prevalence of coronary artery disease detected by CCTA in asymptomatic patients with an intermediate risk of CAD. MATERIALS AND METHODS: We retrospectively selected 185 asymptomatic patients with an intermediate Framingan Risk Score (mean age was 62.3 ± 12.4 years); all patients underwent CCTA, using 640-slice CT. RESULTS: Atherosclerotic plaques were present in 112 out of 185 patients (60.5%); 56 subjects (30.2%) had mild stenosis, 49 (26.5%) moderate stenosis, only 3 patients (1.6%) had severe stenosis and in 4 cases (2.2%) the "blooming effect" did not allow for evaluation of the degree of stenosis. Among the positive cases, a high number of patients (44.6%) [50] showed coronary artery disease in one vessel, 33 patients (29.4%) in two vessels, 22 patients (19.6%) in three vessels and 5 patients in four vessels or more (4.5%). Patients with moderate stenosis were older, had hypertension in most cases, higher total cholesterol levels and more often were smokers. The radiation dose (mSv) dispensed to the patients was 3.7 ± 1.6 mSv. CONCLUSION: High prevalence of coronary stenosis detected by low-dose CCTA in patients not properly classified by the traditional methods of risk stratification commonly used in clinical practice emphasizes the need to extend the risk stratification to other diagnostic tools with higher capability to detect CAD.

Is size an essential criterion to define tumefactive plaque? MR features and clinical correlation in multiple sclerosis.

Tumefactive multiple sclerosis is an inflammatory demyelinating disease of the central nervous system. It has recently been described as a rare subtype of multiple sclerosis (MS) characterised by the appearance of solitary or multiple space-occupying lesions associated with imaging characteristics mimicking neoplasm. Atypical features include plaque size >2 cm with mass effect, oedema, and/or ring enhancement on magnetic resonance (MR) images.This study is a retrospective review designed to evaluate the prevalence of tumefactive plaques in a selected population of 440 MS patients referred to our MS centre in Southern Italy between 2005 and 2014. We analysed the radiographic features of lesions ranging in size from 0.5 to 2 cm to establish whether smaller plaques with MR characteristics similar to tumefactive plaques present different symptoms, disease evolution and prognosis. We also aimed to ascertain if MR features suggestive of biological aggressiveness could be useful prognostic criteria for a correct diagnosis of the disease and subsequent treatment. Our data suggest that lesions 0.5-2 cm and >2 cm have similar MR features and clinical evolution.

Vanishing pineal mass in a young patient without therapy: Case report and review of the literature.

Spontaneous regression is defined as the decrease in size or disappearance of a primary tumour or metastatic disease without therapeutic intervention. Computed tomography and magnetic resonance imaging (MRI) of the brain was performed in a 14-year-old girl experiencing sudden-onset headaches. First diagnostic exams revealed a mass in the pineal region that disappeared at three-month MRI control. Three-year follow-up MRI studies were performed. No therapy was administered, but the pineal lesion had disappeared at three-year follow-up.

Thoracic spine trauma: advanced imaging modality.

Technological advances in diagnostic imaging make the diagnosis of spinal trauma more accurate both in the acute and in the chronic settings. Improvements in medical care and in diagnostic imaging lead to an increasing prevalence of patients' surviving injuries. The management of these patients depends on early and appropriate radiological evaluation in the acute phase. The aim of this work was to review advanced imaging modalities employed to study thoracic spine and spinal cord in injured patients.

Magnetic resonance imaging and magnetic resonance spectroscopy in a young male patient with anti-N-methyl-D-aspartate receptor encephalitis and uncommon cerebellar involvement: A case report with review of the literature.

We report a case of a 17-year-old man presenting with new onset psychiatric symptoms. Magnetic resonance imaging (MRI) and proton magnetic resonance (MR) spectroscopy revealed some lesions in the right cerebellar hemisphere and ipsilateral cerebellar tonsil suggestive of encephalitis. An extensive workup was negative for both infectious and neoplastic diseases and he was afterward diagnosed with anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis. This disorder is an autoimmune encephalitis, highly lethal but curable, predominantly found in young female with ovarian teratoma. He received methylprednisolone. His clinical findings gradually improve and he made a complete recovery. Accordingly, repeated brain MRI and proton MR spectroscopy showed a gradual reduction of the lesions; MRI taken six months after starting therapy showed complete resolution of the lesions. Our case shows that, although rare, anti-NMDAR encephalitis should be considered also in young men for whom a rapid onset of psychiatric neurological disorders cannot be explained by more frequent causes. Our report underlines also the usefulness of MRI and proton MR spectroscopic findings in the diagnosis and follow-up of this disease.

Does evaluator experience have an impact on the diagnosis of lumbar spine instability in dynamic MRI? Interobserver agreement study.

OBJECTIVES: We aimed to evaluate interobserver agreement in the definition of spine instability among spine neuroradiologists with or without experience in dynamic magnetic resonance imaging (MRI). MATERIAL AND METHODS: Two expert neuroradiologists and two residents retrospectively evaluated the pre-operative dynamic MRI examinations of patients with vertebral instability. Segmental motion, defined as excessive (more than 3 mm) translational motion from supine to upright, was investigated in 103 subjects (309 segments) using kinetic MRI. Radiographic parameters which can help indicate segmental instability include disc degeneration, facet joint osteoarthritis, and ligament flavum hypertrophy. These three radiographic parameters were simultaneously evaluated, and the combinations corresponding to significant segmental instability at each level were determined. The agreement among the neuroradiologists was calculated using the kappa coefficient. All patients had neurosurgical intervention to stabilize the spine. RESULTS: Agreement was high among experienced and non-experienced neuroradiologists. Agreement was nearly perfect for spinal location of spinal instability. CONCLUSIONS: This study demonstrates that the experience of the evaluator has a low impact on the assessment of spinal instability if correct classification is used. The interobserver agreement confirms the usefulness and safety of kinetic MRI in the correct diagnosis of spinal instability even by less experienced evaluators.

Italian Registry of Cardiac Computed Tomography.

PURPOSE: Cardiac CT (CCT) is an imaging modality that is becoming a standard in clinical cardiology. We evaluated indications, safety, and impact on patient management of routine CCT in a multicenter national registry. MATERIALS AND METHODS: During a period of 6 months, 47 centers in Italy enrolled 3,455 patients. RESULTS: CCT was performed mainly with 64-slice CT scanners (73.02 %). Contrast agents were administrated in 3,185 patients (92.5 %). Mean DLP changes with type of scanner and was lower in >64 row detector scanner. The most frequent indication for CCT was suspected CAD (44.8 %), followed by calcium scoring (9.6 %), post-angioplasty/stenting (8.3 %), post-CABGs (7.5 %), study of cardiac anatomy (4.22 %) and assessment in patients with known CAD (4.1 %) and acute chest pain (1.99 %). Most of the CCTs were performed in outpatient settings (2,549; 74 %) and a minority in inpatient settings (719, 20.8 %). Adverse clinical events (mild-moderate) occurred in 26 examinations (0.75 %). None of them was severe. In 45.3 % of the cases CCT findings impacted patient management. CONCLUSION: CCT is performed with different workloads in participating centers. It is a safe procedure and its results have a strong impact on patient management.