Effectiveness of 3D T2-Weighted FLAIR FSE Sequences with Fat Suppression for Detection of Brain MR Imaging Signal Changes in Children.

BACKGROUND AND PURPOSE: T2-weighted FLAIR can be combined with 3D-FSE sequences with isotropic voxels, yielding higher signal-to-noise ratio than 2D-FLAIR. Our aim was to explore whether a T2-weighted FLAIR-volume isotropic turbo spin-echo acquisition sequence (FLAIR-VISTA) with fat suppression shows areas of abnormal brain T2 hyperintensities with better conspicuity in children than a single 2D-FLAIR sequence. MATERIALS AND METHODS: One week after a joint training session with 20 3T MR imaging examinations (8 under sedation), 3 radiologists independently evaluated the presence and conspicuity of abnormal areas of T2 hyperintensities of the brain in FLAIR-VISTA with fat suppression (sagittal source and axial and coronal reformatted images) and in axial 2D-FLAIR without fat suppression in a test set of 100 3T MR imaging examinations (34 under sedation) of patients 2-18 years of age performed for several clinical indications. Their agreement was measured with weighted κ statistics. RESULTS: Agreement was "substantial" (mean, 0.61 for 3 observers; range, 0.49-0.69 for observer pairs) for the presence of abnormal T2 hyperintensities and "fair" (mean, 0.29; range, 0.23-0.38) for the comparative evaluation of lesion conspicuity. In 21 of 23 examinations in which the 3 radiologists agreed on the presence of abnormal T2 hyperintensities, FLAIR-VISTA with fat suppression images were judged to show hyperintensities with better conspicuity than 2D-FLAIR. In 2 cases, conspicuity was equal, and in no case was conspicuity better in 2D-FLAIR. CONCLUSIONS: FLAIR-VISTA with fat suppression can replace the 2D-FLAIR sequence in brain MR imaging protocols for children.

Progression of microstructural damage in spinocerebellar ataxia type 2: a longitudinal DTI study.

BACKGROUND AND PURPOSE: The ability of DTI to track the progression of microstructural damage in patients with inherited ataxias has not been explored so far. We performed a longitudinal DTI study in patients with spinocerebellar ataxia type 2. MATERIALS AND METHODS: Ten patients with spinocerebellar ataxia type 2 and 16 healthy age-matched controls were examined twice with DTI (mean time between scans, 3.6 years [patients] and 3.3 years [controls]) on the same 1.5T MR scanner. Using tract-based spatial statistics, we analyzed changes in DTI-derived indices: mean diffusivity, axial diffusivity, radial diffusivity, fractional anisotropy, and mode of anisotropy. RESULTS: At baseline, the patients with spinocerebellar ataxia type 2, as compared with controls, showed numerous WM tracts with significantly increased mean diffusivity, axial diffusivity, and radial diffusivity and decreased fractional anisotropy and mode of anisotropy in the brain stem, cerebellar peduncles, cerebellum, cerebral hemisphere WM, corpus callosum, and thalami. Longitudinal analysis revealed changes in axial diffusivity and mode of anisotropy in patients with spinocerebellar ataxia type 2 that were significantly different than those in the controls. In patients with spinocerebellar ataxia type 2, axial diffusivity was increased in WM tracts of the right cerebral hemisphere and the corpus callosum, and the mode of anisotropy was extensively decreased in hemispheric cerebral WM, corpus callosum, internal capsules, cerebral peduncles, pons and left cerebellar peduncles, and WM of the left paramedian vermis. There was no correlation between the progression of changes in DTI-derived indices and clinical deterioration. CONCLUSIONS: DTI can reveal the progression of microstructural damage of WM fibers in the brains of patients with spinocerebellar ataxia type 2, and mode of anisotropy seems particularly sensitive to such changes. These results support the potential of DTI-derived indices as biomarkers of disease progression.

Whole-lung volume and density in spirometrically-gated inspiratory and expiratory CT in systemic sclerosis: correlation with static volumes at pulmonary function tests.

BACKGROUND: Spiral low-dose computed tomography (LDCT) permits to measure whole-lung volume and density in a single breath-hold. OBJECTIVE: To evaluate the agreement between static lung volumes measured with LDCT and pulmonary function test (PFT) and the correlation between the LDCT volumes and lung density in restrictive lung disease. DESIGN: Patients with Systemic Sclerosis (SSc) with (n = 24) and without (n = 16) pulmonary involvement on sequential thin-section CT and patients with chronic obstructive pulmonary disease (COPD)(n = 29) underwent spirometrically-gated LDCT at 90% and 10% of vital capacity to measure inspiratory and expiratory lung volumes and mean lung attenuation (MLA). Total lung capacity and residual volume were measured the same day of CT. RESULTS: Inspiratory [95% limits of agreement (95% LoA)--43.8% and 39.2%] and expiratory (95% LoA -45.8% and 37.1%) lung volumes measured on LDCT and PFT showed poor agreement in SSc patients with pulmonary involvement, whereas they were in substantial agreement (inspiratory 95% LoA -14.1% and 16.1%; expiratory 95% LoA -13.5% and 23%) in SSc patients without pulmonary involvement and in inspiratory scans only (95% LoA -23.1% and 20.9%) of COPD patients. Inspiratory and expiratory LDCT volumes, MLA and their deltas differentiated both SSc patients with or without pulmonary involvement from COPD patients. LDCT lung volumes and density were not correlated in SSc patients with pulmonary involvement, whereas they did correlate in SSc without pulmonary involvement and in COPD patients. CONCLUSIONS: In restrictive lung disease due to SSc there is poor agreement between static lung volumes measured using LDCT and PFT and the relationship between volume and density values on CT is altered.

Regional analysis of the magnetization transfer ratio of the brain in mild Alzheimer disease and amnestic mild cognitive impairment.

BACKGROUND AND PURPOSE: Manually drawn VOI-based analysis shows a decrease in magnetization transfer ratio in the hippocampus of patients with Alzheimer disease. We investigated with whole-brain voxelwise analysis the regional changes of the magnetization transfer ratio in patients with mild Alzheimer disease and patients with amnestic mild cognitive impairment. MATERIALS AND METHODS: Twenty patients with mild Alzheimer disease, 27 patients with amnestic mild cognitive impairment, and 30 healthy elderly control subjects were examined with high-resolution T1WI and 3-mm-thick magnetization transfer images. Whole-brain voxelwise analysis of magnetization transfer ratio maps was performed by use of Statistical Parametric Mapping 8 software and was supplemented by the analysis of the magnetization transfer ratio in FreeSurfer parcellation-derived VOIs. RESULTS: Voxelwise analysis showed 2 clusters of significantly decreased magnetization transfer ratio in the left hippocampus and amygdala and in the left posterior mesial temporal cortex (fusiform gyrus) of patients with Alzheimer disease as compared with control subjects but no difference between patients with amnestic mild cognitive impairment and either patients with Alzheimer disease or control subjects. VOI analysis showed that the magnetization transfer ratio in the hippocampus and amygdala was significantly lower (bilaterally) in patients with Alzheimer disease when compared with control subjects (ANOVA with Bonferroni correction, at P < .05). Mean magnetization transfer ratio values in the hippocampus and amygdala in patients with amnestic mild cognitive impairment were between those of healthy control subjects and those of patients with mild Alzheimer disease. Support vector machine-based classification demonstrated improved classification performance after inclusion of magnetization transfer ratio-related features, especially between patients with Alzheimer disease versus healthy subjects. CONCLUSIONS: Bilateral but asymmetric decrease of magnetization transfer ratio reflecting microstructural changes of the residual GM is present not only in the hippocampus but also in the amygdala in patients with mild Alzheimer disease.

Looking at my body. Similarities and differences between anorexia nervosa patients and controls in body image visual processing.

BACKGROUND: Body image distortion is a core symptom of eating disorders. Functional magnetic resonance imaging (fMRI) studies on body image processing, described different patterns of neural response, mainly involving the inferior and superior parietal lobules, and the dorsolateral prefrontal cortex (DLPFC), with conflicting results. METHODS: The neural response to the view of their own body pictures (normal size and distorted) was evaluated in 18 female anorexia nervosa (AN) restricting type patients, and in 19 healthy female subjects (HC) using fMRI. Clinical assessment was performed by means of the structured clinical interview for DSM-IV and self-reported questionnaires. RESULTS: In response to the body image distortion, patients and controls showed an inverse pattern of activation, with the widest extent of activation in the oversize condition in AN, while in the undersize condition in HC. AN and HC showed a similar pattern of neural response to the view of their own body, with an increased activation in the extrastriate body area, superior and inferior parietal lobule and prefrontal areas, although the extent of activation in HC was more limited as compared with AN patients. Increased activity in AN patients, compared with HC, was observed in the DLPFC in response to the oversized body picture and a significant correlation was found in AN patients between DLPFC activation and eating disorder psychopathology. CONCLUSIONS: Our findings suggest the existence of a continuum from normalcy to pathology in neural response to body image, and confirm the clinical relevance of body image distortion in AN, reinforcing the key role of attentive, executive and self-evaluation networks in AN visual processing of own distorted body image.

Screening for lung cancer using low-dose spiral CT: 10 years later, state of the art.

Ten years after the first papers on this subject, this editorial represents a brief review on lung cancer screening with low-dose spiral CT. The aim is to present the main theoretical and practical problems related to lung cancer screening, the historical background and results of observational studies and the main ongoing randomised controlled trials. In particular, the National Lung Screening Trial (NLST), which was interrupted early, is discussed. The opinion of the authors is that too many questions are still awaiting an answer.

E-learning in radiology: an Italian multicentre experience.

OBJECTIVE: The aim of this study was to design, deliver and evaluate an e-learning teaching programme for post-graduate radiodiagnostics training that would involve various post-graduate schools throughout Italy. MATERIALS AND METHODS: All of the Directors of Italian post-graduate schools of radiodiagnostics were sent an e-mail on 27 September 2010 informing them of our willingness to set up an e-learning project for the academic year 2010-2011 in the form of single-subject teaching seminars. The proposed subjects were the semeiotics of the various organs and apparatuses in the context of "Urgent/Emergency Pathology". After having received registrations, a calendar of lessons was planned to be held between 10 November 2010 and 12 October 2011. The validity of the project was tested by means of a multiple-choice questionnaire covering the technical and didactic quality of the entire project, to be completed by the students. RESULTS: Fifty-one percent of the universities in Italy participated in the project: Trieste, Udine, Verona, Milan-Bicocca, Novara, Varese, Genoa, Sassari, Rome Campus, the Catholic University of Rome, Chieti, Foggia, Catania, Modena, Florence, Palermo, Bologna, Pavia, Parma and Ferrara. The lessons were attended by a total of 10,261 post-graduate medical students, for an average of 513.1 students per lesson. Seventy percent of the students judged the didactic content "excellent", 25% "good", and 5% "satisfactory"; none said it was unsatisfactory. In terms of visual quality (particularly the details of the radiological images proposed in the form of slides and/or video clips), 73% judged it "excellent", 20% "good", 6% "satisfactory", and 1% "poor". The audio quality was judged "excellent" by 71%, "good" by 22%, "satisfactory" by 6% and "poor" by 1%. In relation to judgement of audio and video quality, it has to be underlined that this was greatly affected by the hardware/software configuration and the band speed and technology of the Internet connection. CONCLUSIONS: Technological evolution is overcoming all barriers, and technology is also having a positive impact on the approach to teaching. Our multicentre teaching experience merits the following considerations: the quality of the teaching product was certified by the students' judgements of its didactic content and the quality of reception; the economic cost of the teaching had a minimal impact on the post-graduate schools (€ 18 per lesson). In terms of breaking down national barriers, it is to be hoped that the coordination and integration of diagnostic imaging e-learning projects, with the participation of post-graduate schools in different European countries, can be developed not only in a spirit of "cultural sharing" and the exchange of teaching experiences.

Dose exposure in the ITALUNG trial of lung cancer screening with low-dose CT.

Few data are available on the effective dose received by participants in lung cancer screening programmes with low-dose CT (LDCT). We report the collective effective dose delivered to 1406 current or former smokers enrolled in the ITALUNG trial who completed 4 annual LDCT examinations and related further investigations including follow-up LDCT, 2-[(18)F]flu-2-deoxy-d-glucose positron emission tomography (FDG-PET) or CT-guided fine needle aspiration biopsy (FNAB). Using the air CT dose index and Monte Carlo simulations on an anthropomorphic phantom, the whole-body effective dose associated with LDCT was determined for the eight CT scanners used in the trial. A value of 7 mSv was assigned to FDG-PET while the measured mean effective dose of CT-guided FNAB was 1.5 mSv. The mean collective effective dose in the 1406 subjects ranged between 8.75 and 9.36 Sv and the mean effective dose to the single subject over 4 years was between 6.2 and 6.8 mSv (range 1.7-21.5 mSv) according to the cranial-caudal length of the LDCT volume. 77.4% of the dose was owing to annual LDCT and 22.6% to further investigations. Considering the nominal risk coefficients for stochastic effects after exposure to low-dose radiation according to the National Radiological Protection Board, International Commission on Radiological Protection (ICRP) 60, ICRP103 and Biological Effects of Ionizing Radiation VII, the mean number of radiation-induced cancers ranged between 0.12 and 0.33 per 1000 subjects. The individual effective dose to participants in a 4-year lung cancer screening programme with annual LDCT is very low and about one-third of the effective dose that is associated with natural background radiation and diagnostic radiology in the same time period.

Novel approach to the microscopic inspection during laser cleaning treatments of artworks.

The present work focuses on the potential of 3D digital microscopy for assessing micro-morphological features during laser cleaning treatments of artworks. This application requires preliminary optimization studies aimed at defining operative irradiation parameters and practicable degree of cleaning, as well as in situ diagnostic assessments during the restoration work. To this goal, we developed and tested a dedicated 3D digital microscope by implementing the "shape-from-focus" technique. The significant potential of this instrument, which provides textural and chromatic information, was proven for the phenomenological characterization of black crust removal from stones, earthy concretion from bronzes and dark varnish from easel paintings. Comparative measurements using 3D digital microscopy and contact microprofilometry were performed after laser cleaning tests of prepared samples, genuine archaeological bronze artefacts and a stone sculptural element from Florence's Dome. The results achieved demonstrate the effectiveness and reliability of the novel approach and the advantages it provides with respect to alternative techniques, which will allow the methods to be used in the wider restoration community.

Progress in restorative neurosurgery: human fetal striatal transplantation in Huntington's disease. Review.

The purpose of this paper was to offer a review of the rationale, methods, biological and clinical results of human fetal striatal transplantation (HFST) in the treatment of Huntington's disease (HD). HD is a heritable neurodegenerative disease in which degeneration of neurons in the striatum leads to motor, psychiatric and cognitive deficits. The disease is progressive and inexorably lethal. At present there are no curative treatments for HD. A restorative therapy based on the intrastriatal transplantation of striatal neuroblasts taken from human fetus is currently being explored as potential treatment in selected HD patients. Pilot clinical trials of HFST have been started in few neurosurgery restorative centres. Results demonstrated that HFST is feasible and safe without relevant adverse effects; grafted neuroblasts survive, grow without evidence of neoplasia or teratoma, build new tissue with striatal-like imaging features, and move into the host brain towards short and long-distance cortical and sub-cortical targets. HFST delays disease progression and provides a period of improvement and stability. Even though larger-scale studies are still necessary to establish the true value of such a treatment, at this time, HFST represents a promising experimental therapy for patients with HD and one of the most interesting clinical application of restorative neurosurgery.

Magnetization transfer imaging demonstrates a distributed pattern of microstructural changes of the cerebral cortex in amyotrophic lateral sclerosis.

BACKGROUND AND PURPOSE: To date, damage of the cerebral cortex neurons in ALS was investigated by using conventional MR imaging and proton MR spectroscopy. We explored the capability of MTI to map the microstructural changes in cerebral motor and extramotor cortices of patients with ALS. MATERIALS AND METHODS: Twenty patients with ALS and 17 age-matched healthy controls were enrolled. A high-resolution 3D SPGR sequence with and without MT saturation pulses was obtained on a 1.5T scanner to compute MTR values. Using the FMRIB Software Library tools, we automatically computed the MTR of the cerebral cortex GM in 48 regions of the entire cerebral cortex derived from the standard Harvard-Oxford cortical atlas. RESULTS: The MTR values were significantly lower in patients with ALS than in healthy controls in the primary motor cortex (precentral gyrus), nonprimary motor areas (superior and middle frontal gyri and superior parietal lobe), and some extramotor areas (frontal pole, planum temporale, and planum polare). No correlation was found between regional MTR values and the severity of clinical deficits or disease duration. CONCLUSIONS: MTI analysis can detect the distributed pattern of microstructural changes of the GM in the cerebral cortex of patients with ALS with involvement of both the motor and extramotor areas.

Magnetization transfer MR imaging demonstrates degeneration of the subcortical and cortical gray matter in Huntington disease.

BACKGROUND AND PURPOSE: GM is typically affected in HD since the presymptomatic stage. Our aim was to investigate with MT MR imaging the microstructural changes of the residual brain subcortical and cortical GM in carriers of the HD gene and to preliminarily assess their correlation with the clinical features. MATERIALS AND METHODS: Fifteen HD gene carriers with a range of clinical severity and 15 age- and sex-matched healthy controls underwent MT MR imaging on a 1.5T scanner. The MT ratio was measured automatically in several subcortical and cortical GM regions (striatal nuclei; thalami; and the neocortex of the frontal, temporal, parietal, and occipital lobes) by using FLS tools. RESULTS: The MT ratio was significantly (P < .05 with Bonferroni correction for multiple comparison) decreased in all subcortical structures except the putamen and decreased diffusely in the cerebral cortex of HD carriers compared with controls. Close correlation was observed between the subcortical and cortical regional MT ratios and several clinical variables, including disease duration, motor disability, and scores in timed neuropsychological tests. CONCLUSIONS: MT imaging demonstrates degeneration of the subcortical and cortical GM in HD carriers and might serve, along with volumetric assessment, as a surrogate marker in future clinical trials of HD.

CT colonography before colonoscopy in subjects with positive faecal occult blood test. Preliminary experience.

PURPOSE: We report a preliminary evaluation of the performance of computed tomography colonography (CTC) systematically obtained before optical colonoscopy (OC) in subjects with positive faecal occult blood test (FOBT) within a population-based screening programme for colorectal cancer (CRC). MATERIALS AND METHODS: Seventy-nine subjects with positive FOBT from a regional screening programme were invited to perform same day CTC and OC. CTC was performed with standard bowel preparation. OC with segmental unblinding was the reference standard. A per-patient per-adenoma analysis was performed. RESULTS: Forty-nine of 79 subjects (62%) with positive FOBT adhered to the study and completed both examinations. Twenty-two (44.9%) of the 49 had a cancer or an adenoma ≥6 mm. Per-patient sensitivity, specificity, negative predictive value and positive predictive value for cancer or adenoma ≥6 mm were 95.5% (95%CI:77.2%-99.9%), 51.9% (95%CI:32.0%-71.3%), 93.3% (95%CI:68.1%-99.8%) and 61.8% (95%CI:43.6%-77.8%). CONCLUSIONS: In the setting of a FOBT-based screening programme for CRC, CTC showed a high sensitivity, but relatively low specificity and positive predictive value, for cancer and adenoma ≥6 mm. Probably performing CTC without faecal tagging as second line test after a positive FOBT is not a cost-effective strategy.

Regional distribution and clinical correlates of white matter structural damage in Huntington disease: a tract-based spatial statistics study.

BACKGROUND AND PURPOSE: HD entails damage of the WM. Our aim was to explore in vivo the regional volume and microstructure of the brain WM in HD and to correlate such findings with clinical status of the patients. MATERIALS AND METHODS: Fifteen HD gene carriers in different clinical stages of the disease and 15 healthy controls were studied with T1-weighted images for VBM and DTI for TBSS. Maps of FA, MD, and λ∥ and λ⊥ were reconstructed. RESULTS: Compared with controls, in addition to neostriatum and cortical GM volume loss, individuals with HD showed volume loss in the genu of the internal capsule and subcortical frontal WM bilaterally, the right splenium of the corpus callosum, and the left corona radiata. TBSS revealed symmetrically decreased FA in the corpus callosum, fornix, external/extreme capsule, inferior fronto-occipital fasciculus, and inferior longitudinal fasciculus. Areas of increased MD were more extensive and included arciform fibers of the cerebral hemispheres and cerebral peduncles. Increase of the λ∥ and a comparatively more pronounced increase of the λ⊥ underlay the decreased FA of the WM in HD. Areas of WM atrophy, decreased FA, and increased MD correlated with the severity of the motor and cognitive dysfunction, whereas only the areas with increased MD correlated with disease duration. CONCLUSIONS: Microstructural damage accompanies volume decrease of the WM in HD and is correlated with the clinical deficits and disease duration. MR imaging-based measures could be considered as a biomarker of neurodegeneration in HD gene carriers.

The present and the future of neuroimaging in amyotrophic lateral sclerosis.

In patients with ALS, conventional MR imaging is frequently noninformative, and its use has been restricted to excluding other conditions that can mimic ALS. Conversely, the extensive application of modern MR imaging-based techniques to the study of ALS has undoubtedly improved our understanding of disease pathophysiology and is likely to have a role in the identification of potential biomarkers of disease progression. This review summarizes how new MR imaging technology is changing dramatically our understanding of the factors associated with ALS evolution and highlights the reasons why it should be used more extensively in studies of disease progression, including clinical trials.

Hemodynamic patterns of chronic cerebrospinal venous insufficiency in multiple sclerosis. Correlation with symptoms at onset and clinical course.

AIM: Chronic cerebrospinal venous insufficiency (CCSVI) is associated with multiple sclerosis (MS). CCSVI is detected by transcranial and extracranial color-Doppler high-resolution examination (TCCS-ECD) and venography that permit to identify five types of venous malformations and four major (A-D) hemodynamic patterns of anomalous extracranial-extravertebral venous outflow. We investigated possible correlation between such hemodynamic patterns and both the symptoms at onset and clinical course in patients with MS and CCSVI. METHODS: TCCS-ECD, selective venography and clinical records of 65 patients affected by definite MS and CCSVI were reviewed. RESULTS: The four hemodynamic patterns of CCSVI were unevenly (P<0.0001) distributed with respect to the types of clinical presentation and course. In particular the Type A or B patterns were common in patients with onset of optic neuritis, but rare in patients presenting with spinal cord symptoms who typically showed a type D pattern. As well, the type A or type B hemodynamic were more common in patients with relapsing remitting course than in patients with secondary progressive course and rare in patients with primary progressive course. The C hemodynamic pattern was not observed in patients with primary progressive course who showed a remarkable prevalence of the type D pattern. CONCLUSION: The distribution of venous malformations and the resulting hemodynamic pattern show correlation with symptoms at onset and clinical course in patients with MS and CCSVI.

Clinical Recovery despite Cortical Cerebral and Cerebellar Damage in Heat Stroke.

The prognosis of heat stroke has considerably improved with a mortality rate drop to 10% when therapeutic measurements including external cooling and aggressive rehydration are adopted. The role of imaging in predicting prognosis is uncertain. Some noted that development of cortical cerebellar atrophy is associated with development of a pancerebellar syndrome, while others suggested that evidence of cerebral cortical damage due to hypoxic-ischemic injury implies a poor prognosis. We observed a 17-year-old female who presented with lost of consciousness and seizure while jogging on a hot summer day followed by multi-organ failure. Brain MRI revealed a symmetric area of T2 hyperintensity and decreased diffusion in the cortical gyri of the frontal lobes. The patient made a complete recovery. MRI two years later showed disappearance of signal changes in the frontal cortex, but progressive atrophy of the cerebellum which was clinically silent. Our observation challenges the view of a close correlation between the imaging findings and prognosis in heat stroke.