Correction to: Dynamic susceptibility contrast (DSC) perfusion MRI in differential diagnosis between radionecrosis and neoangiogenesis in cerebral metastases using rCBV, rCBF and K2.

In the original publication of the article, the name of the last author was incorrect. The correct name should read as given below.

Dynamic susceptibility contrast (DSC) perfusion MRI in differential diagnosis between radionecrosis and neoangiogenesis in cerebral metastases using rCBV, rCBF and K2.

INTRODUCTION: Distinction between treatment-related changes and tumour recurrence in patients who have received radiation treatment for brain metastases can be difficult on conventional MRI. In this study, we investigated the ability of dynamic susceptibility contrast (DSC) perfusion in differentiating necrotic changes from pathological angiogenesis and compared measurements of relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF) and K2, using a dedicated software. METHODS: Twenty-nine patients with secondary brain tumors were included in this retrospective study and underwent DSC perfusion MRI with a 3-month follow-up imaging after chemo- or radiation-therapy. Region-of-interests were drawn around the contrast enhancing lesions and measurements of rCBV, rCBF and K2 were performed in all patients. Based on subsequent histological examination or clinico-radiological follow-up, the cohort was divided in two groups: recurrent disease and stable disease. Differences between the two groups were analyzed using the Student's t test. Sensitivity, specificity and diagnostic accuracy of rCBV measurements were analyzed considering three different cut-off values. RESULTS: Between patients with and without disease, only rCBV and rCBF values were significant (p < 0.05). The only cut-off value giving the best diagnostic accuracy of 100% was rCBV = 2.1 (sensitivity = 100%; specificity = 100%). Patients with tumor recurrence showed a higher mean value of rCBV (mean = 4.28, standard deviation = 2.09) than patients with necrotic-related changes (mean = 0.77, standard deviation = 0.44). CONCLUSION: DSC-MRI appears a clinically useful method to differentiate between tumor recurrence, tumor necrosis and pseudoprogression in patients treated for cerebral metastases. Relative CBV using a cut-off value of 2.1 proved to be the most accurate and reliable parameter.

Mediastinal irradiation in a patient affected by lung carcinoma after heart transplantation: Helical tomotherapy versus three dimensional conformal radiotherapy.

Patients who have undergone solid organ transplants are known to have an increased risk of neoplasia compared with the general population. We report our experience using mediastinal irradiation with helical tomotherapy versus three-dimensional conformal radiation therapy to treat a patient with lung carcinoma 15 years after heart transplantation. Our dosimetric evaluation showed no particular difference between the techniques, with the exception of some organs. Mediastinal irradiation after heart transplantation is feasible and should be considered after evaluation of the risk. Conformal radiotherapy or intensity-modulated radiotherapy appears to be the appropriate treatment in heart-transplanted oncologic patients.

Dynamic MR in patients affected by neurogenical claudication: technique and results from a single-center experience.

INTRODUCTION: This study aimed to determine changes in size of lumbar spinal canal and related articular structures, during dynamic MR scans acquired in symptomatic patients standing upright using a new open MR system. METHODS: Forty patients (mean age 58.4 years) affected by lumbar back pain associated with claudication, referring symptoms since more than 6 months. No one underwent to previous spine surgery. MR scans were performed with a novel open 0.5-T scanner, patient supine and upright (90°). Lumbar lordotic angle, flavum ligament thickness, herniated discs, spinal canal area, spinal canal and dural sac antero-posterior diameters, and spinal alignment were measured and compared in both supine and upright positions. Mean scanning time was 43 min. RESULTS: All the considered parameters showed a statistically significant difference, except for lumbar lordotic angle. Mean percentage differences moving from supine to upright were +3.9 % for lumbar lordotic angle, +15 % for flavum ligament thickness, +16.2 % for sagittal disc bulge, -10.8 % for dural sac diameter, -13.1 % for spinal canal diameter, and -15.8 % for spinal canal area. In supine position, no patient presented with spondylolisthesis; moving to upright position, four patients showed spondylolisthesis (grade I). CONCLUSION: Dynamic MR is a valuable diagnostic exam to analyze the structures involved in lumbar back pain due to spinal canal stenosis and spondylolisthesis; in supine position, relevant factors can be underestimated or hidden, becoming appreciable only patient standing upright. In this series, flavum ligament thickening presented a role comparable to disc bulge for narrowing of lumbar spinal canal.

Non-alcoholic acute Wernicke's encephalopathy: role of MRI in non typical cases.

AIM: Acute Wernicke's encephalopathy (WE) is a severe neurological disorder caused by thiamine deficiency, most commonly found in chronic alcoholics. It is not so easy to suspect acute WE when the clinical picture does not include all the typical symptoms and alcohol abuse is not reported. Three rare cases of Wernicke's encephalopathy (WE) in non-alcoholic patients are reported. CASES PRESENTATION: Two patients developed the disease following prolonged intravenous feeding, the third was carrying a gastric lymphoma. None of them presented with the classic clinical triad of WE (ophtalmoplegia/nystagmus, ataxia and consciousness disturbance), showing just one or two of the typical symptoms. Brain Magnetic Resonance Imaging (MRI) represented the key tool to suspect and define WE diagnosis, showing a picture characterized by bilaterally altered signal of the thalamic pulvinar, mesencephalic cup, mammillary bodies, periaqueductal grey matter and floor of fourth ventricle. All patients dramatically improved within 48 h after administration of thiamine. CONCLUSION: We emphasize that WE should be suspected in all patients showing typical MRI features presenting with at least one of the clinical triad of WE.