MRgFUS thalamotomy for the treatment of tremor: evaluation of learning curve and operator's experience impact on the procedural and clinical outcome.

BACKGROUND: MRgFUS Vim ablation is increasingly used for the treatment of tremor in ET e PD patients but there is little published research on the importance of operator experience in this procedure. This study aims to evaluate the learning curve and the influence of the operator experience on the procedural and clinical outcomes. METHODS: We retrospectively evaluated 90 patients (38 ET, 52 PD) submitted to MRgFUS unilateral thalamotomy in the period between February 2018 and July 2020. Clinical endpoints, procedural times, and technical parameters were recorded in all procedures. Based on the time of treatment, patients were divided into three groups of 30 units each, comparing all variables between each time period group. RESULTS: In Group A, the average patient preparation time was 120.6 min, the treatment time was 105.2 min, the number of was sonications 14.1, and the mean target shifts 3.1. In Group B, the mean preparation time was 105.5 min, the treatment time was 89.5 min, the number of sonications was 13.2, and the target shifts 3.0. Group C showed inferior values of preparation time (101.9 min), treatment time (71.7 min), numbers of sonications (10.6), and shifts (1.7). Thalamotomy-related complications occurred in 9 patients of Group A, 2 of Group B, and 5 of Group C. Tremor relapse occurred in 7 patients of Group A, 3 of Group B, and 2 of Group C. The days of hospitalization were comparable in the three groups. CONCLUSIONS: The operators experience is associated with the improvement of clinical and procedural outcome in MRgFUS thalatomy for the treatment of ET and PD tremor.

Prognostic value of brain tissues' volumes in patients with essential tremor treated with MRgFUS thalamotomy.

MRgFUS Vim thalamotomy is a novel, effective, minimally invasive therapeutic option for patients with essential tremor (ET). Among the selection criteria, some parameters related to the patient's anatomy, such as the skull density ratio (SDR), are well recognized. The role of brain tissue interposed between the target and the ultrasound transducers has never been explored. Therefore, the purpose of our study was to evaluate the correlation and the possible predictive value between brain tissue volumes (grey matter - GM, white matter - WM, and cerebrospinal fluid - CSF) and several treatment-related variables (periprocedural parameters, MRI imaging findings, and the clinical outcome). We analysed data from thirty ET patients previously submitted to MRgFUS thalamotomy. Pre-treatment images were automatically segmented in sopra-tentorial (ST) WM, GM, and CSF using SPM 12. The most significant findings were a positive correlation of the ST-GM with the Accumulated Thermal Dose (ATD) (p < 0,001) and a negative correlation of the ATD temperature with ST-CSF and ST-TIV (p < 0,001). Ultrasound propagation speed is lower in fluids than brain tissues. Also, WM has an attenuation rate of 1.5 higher than the GM. Therefore, the difference in the ATD may be explained by the different acoustic properties of normal brain tissues interposed between the transducers and the VIM.

Neural correlates of observation of disgusting images in subjects with first episode psychosis and post-traumatic stress disorder.

The aim of this study was to analyze neural responses to disgusting images in individuals with first episode psychosis and post-traumatic stress disorder (PTSD). Although anhedonia is a common symptom in both disorders we expected that they would be associated with different neurophysiological abnormalities and patterns of activation. We recruited three groups of participants: 13 individuals with first episode psychosis, 10 individuals with PTSD who had survived the April 2009 L’Aquila earthquake and 25 healthy controls matched for age and education. All individuals participated in a functional imaging experiment in which they watched six alternating blocks of disgusting and scrambled images whilst undergoing scanning with a General Electric 1.5T whole-body scanner. We estimated individuals'’ beta-weights, extracting 22 clusters corresponding to 22 significant areas. Findings were consistent with other neuroimaging studies; the active areas (i.e. amygdala, insula, inferior and medial frontal gyrus) have consistently been associated with emotional experiences. Statistical analysis revealed important group differences in intensity and direction (positive or negative) of signal from baseline during disgusting condition. Although these results are preliminary they show that functional neuroimaging techniques may make a valuable contribution to differential diagnosis of first episode psychosis and PTSD.

A rare case of intracranial rosai-dorfman disease mimicking multiple meningiomas. A case report and review of the literature.

Rosai-Dorfman disease (RDD) was firstly described in 1969 as a benign proliferative disorder of histiocytes with systemic symptoms and lymphadenopathy. This disease is of uncertain pathogenesis and mostly occurs in children and young adults. The typical clinical features of RDD include bilateral painless cervical lymphadenopathy, but extranodal involvement may also be present. The most common extranodal sites include organs such as the respiratory tract, skin, nasal cavity, orbit and bone. Isolated central nervous system (CNS) manifestations are extremely rare. In case of CNS involvement, the commonest imaging findings are dural-based extra-axial enhancing masses. We describe a case of intracranial RDD mimicking multiple meningiomas both clinically and radiologically in a 57-year-old man presenting with a six-year history of progressive right visual and hearing loss and tinnitus. In cases of multiple extra-axial lesions it is worth bearing in mind the possible differential diagnosis for intracranial RDD and eventually propose to the patient further investigations.

Pediatric inflammatory diseases. Part I: multiple sclerosis.

Multiple sclerosis (MS) is an inflammatory CNS disease characterized by multifocal areas of demyelination; usually it arises in young adults, but can also occur in children (under the age of 10) and adolescents (under the age of 18). As in adult, pediatric MS (PMS) diagnosis is based on the demonstration of multiple demyelination episodes separated in time and spaces. Diagnostic criteria realized for childhood are similar to those employed for adults. Although clinical and imaging features of PMS can be similar to those of adults, the disease is often characterized by a more aggressive course and atypical imaging findings, with giant and pseudotumoral plaques. Differential diagnosis between PMS and ADEM could be difficult: clinical findings and MRI are necessary; sometimes MRI follow-up is required for definitive diagnosis.

Pediatric Inflammatory Diseases. Part III: Small Vessels Vasculitis.

Central nervous system (CNS) vasculitis can affect both adults and children, but some of these occur almost exclusively in childhood. In children may develop as a primary condition or secondary to an underlying systemic disease. Cerebral vasculitis can be classified on the basis of the diameter of the involved vessels, although there is no univocal consensus. The diagnosis of CNS vasculitis is particularly difficult because the available investigative modalities have limited sensitivities and specificities. The most helpful diagnostic tests include cerebrospinal fluid analysis, MRI (MR angiography/venography (MRA/MRV) of the brain, and angiography. However, brain biopsy may be required to diagnose small vessel vasculitis in order to make differential diagnosis with a wide range of conditions, such as degenerative vasculopathies, embolic diseases, or coagulation disorders. This paper discusses on current understanding of most frequent primary and secondary central nervous system vasculitis in children in which are involved small vessel.

Change in regional cerebral function in l'aquila earthquake survivors with post-traumatic stress disorder: preliminary findings.

Subjects with post-traumatic stress disorder (PTSD) present a diminished or blunted emotional response, sometimes called "emotional numbing" (EN), that constitutes one of the central symptoms in PTSD. Symptoms of EN include diminished interest in activities, feeling detached or estranged from others, and restricted range of affect (American Psychiatric Association, 2000). The present work studied the emotional components in individuals with PTSD with the principal aim of investigating subjects' functional alteration in the limbic regions, insula and frontal cortex during an emotional task compared with healthy subjects. Ten subjects with PTSD (survivors of the 6.3 magnitude earthquake of April 6, 2009 in L'Aquila) and ten healthy controls underwent fMRI. PTSD was diagnosed according to DSM-IV-R (APA 2000). All subjects underwent fMRI while viewing content-neutral and emotional stimuli. Data analysis revealed that PTSD subjects had significantly greater cerebral activation in particular in the right anterior insula and in bilateral inferior frontal gyrus. Our data suggest that there is a change in the activation of brain areas responsible for emotional processing in patients with PTSD and are consistent with previous findings demonstrating hyperactivation in frontolimbic structures during emotional tasks. Our study suggests that close personal experience may be critical in engaging the neural mechanisms underlying the emotional modulation of memory. Our findings provide evidence that significant alterations in brain function, similar in many ways to those observed in PTSD, can be seen shortly after major traumatic experiences, highlighting the need for early evaluation and intervention for trauma survivors.

Neuronal basis of haedonic appraisal in early onset schizophrenia: FMRI investigation.

The most important symptoms associated with schizophrenia are affective flattening, decreased expression of emotions, anhedonia and social isolation. The purpose of the present study was to investigate the neural response to disgusting and pleasant visual stimuli in healthy subjects and in patients with first-episode schizophrenia. Twelve subjects in the first episode of schizophrenia (DSM-IV-R, APA, 2000) with a normal IQ and 12 healthy volunteers selected for age and education underwent functional magnetic resonance imaging (fMRI) during observation of pleasant and disgusting visual stimuli. Analysis showed that in healthy subjects, the prefrontal cortex and limbic areas are activated in response to pleasant and disgusting visual stimuli, whereas this does not occur in subjects with schizophrenia since the first episode of illness.

Soft tissue liposarcoma: histological subtypes, MRI and CT findings.

PURPOSE: Liposarcoma is the second most common malignancy of soft tissues. The commonly accepted classification of liposarcoma includes five basic histological categories: well-differentiated, myxoid, round cell, dedifferentiated and pleomorphic liposarcoma. The clinical behaviour of liposarcoma closely reflects its histological appearance, so that to identify the histological subtypes is very important for both prognosis and therapy. The aim of this study was to ascertain whether the histological features of liposarcoma subtypes can be correlated with MRI (Magnetic Resonance Imaging) and CT (Computed Tomography) findings by retrospectively evaluating nineteen cases of histologically-proved liposarcoma. MATERIALS AND METHODS: The MRI examinations performed over the past eight years on nineteen patients affected by liposarcoma were retrospectively reviewed. All patients underwent ultrasound and MRI examination; T2 and T1-weighted sequences were available in all cases and fat-saturated sequences in 4 cases; all patients were administered paramagnetic contrast material. CT scans were obtained in twelve patients. All patients had a biopsy, surgical resection and histology. RESULTS: The study group had 7 well-differentiated, 8 myxoid, 3 pleomorphic and 1 round cell liposarcoma. Well-differentiated liposarcomas had largely lipomatous appearance on both CT and MRI, typically with septa and areas showing high signal intensity on T2w MR images and low signal intensity on T1w images, and slightly hypodense compared to the muscle in CT, representing the sarcomatous areas. Myxoid liposarcomas were mildly heterogeneous with typical high signal intensity on T2w images and isointense to the muscle in T1w images, with lacy or linear septa of fatty tissue in six cases. The pleomorphic and round-cell subtypes demonstrated marked heterogeneity on MR images, with areas of necrosis and heterogeneous contrast enhancement, indistinguishable from other high-grade sarcomas. DISCUSSION AND CONCLUSIONS: Well-differentiated liposarcoma may be distinguished from other types of liposarcoma by its largely lipomatous appearance. Myxoid liposarcoma may be distinguished on the basis of its homogeneous or mildly heterogeneous structure due to the large amounts of the extracellular myxoid material that give it its typical MR appearance. Both well-differentiated and myxoid liposarcomas, the most common types accounting for about 50% of all liposarcomas, have a more favourable clinical behaviour than the other histological types. Differentiation of these from the other histological types of liposarcoma therefore has a high significance for prognosis and therapeutical approach. On the basis of our experience and of the literature, we believe that diagnostic imaging and in particular the MR examination may lead to a correct diagnosis.

Spontaneous involution of pilocytic astrocytoma in a patient without neurofibromatosis type 1: case report.

Serial magnetic resonance imaging findings are described in a patient with a sporadically occurring pilocytic astrocytoma that underwent spontaneous regression over 6 years. To the authors' knowledge, this is the first report in which spontaneous involution of a pilocytic astrocytoma not associated with neurofibromatosis type 1 has been described. A literature review regarding sporadic and syndrome-associated pilocytic astrocytoma was undertaken, with particular reference to treatment and natural history.

Left ventricular function: MRI assessment.

Biplane left ventricular (LV) angiography has always been considered the standard of reference to measure LV volumes and ejection fraction (EF): however, angiographic measurements depend on the assumption of geometric models derived from two-dimensional information. MRI is the best technique to evaluate cardiac volumes and mass providing direct non geometric analysis of the ventricles with a high contrast resolution. Standard cine MRI is considered a time-consuming technique for acquisition and measurements; breath hold cine MRI and echoplanar imaging (EPI) non gated sequences are useful to reduce the acquisition time from a few minutes to a few seconds. The evaluation of the heart linear parameters (diameters, thickness), areas, volumes and mass is essential in the diagnosis of many heart diseases and in the assessment of the ventricular function. The modalities to evaluate LV measurements and to obtain functional parameters, the acquisition technique and flow analysis were analyzed in this study.

[Anterior cruciate ligament tears in athletes: assessment and clinico-diagnostic control with a dedicated system]. / Lesioni del legamento crociato anteriore negli atleti: valutazione e controlli clinico-diagnostici utilizzando apparecchio dedicato.

INTRODUCTION: We investigated the MR signs of anterior cruciate ligament (ACL) tears and tried to assess the patterns of both the acute and the chronic phases since more MR examinations are currently performed of the knee joint in the hyper and acute post-traumatic stage. MATERIAL AND METHODS: December, 1994, through September, 1997, a hundred and 89 sportsmen with a history of hyper and acute knee trauma were submitted to MRI: one hundred and four of them were followed-up for 3-6 months. The MR examinations were performed with a dedicated unit (Artoscan, Esaote Biomedica, Genoa) using T1-weighted SE, T2-weighted GE and Turbo ME sequences on the sagittal, coronal and axial planes, respectively (3-5 mm slice thickness). RESULTS: Of 189 patients examined in the hyper and acute post-traumatic stage, 101 had a complete ACL tear, 23 had a partial tear and 65 had an enlarged and inhomogeneous ACL: Eighty-five patients underwent surgery, while the other 104 had 3-6 months' follow-up MRI. Twenty-four of the latter had a complete ACL tear, 20 had a partial tear and 60 had no MR finding of ACL interruption, with a more or less inhomogeneous ligament. DISCUSSION: ACL tears are difficult to demonstrate in the acute phase because of perilesional swelling, synovitis and hemorrhage; high-contrast sequences on the axial plane are therefore required. In the chronic stage, an uninterrupted ACL does not necessarily imply that function is preserved, as well as the MR finding of a deflected ligament does not necessarily imply altered biomechanics. CONCLUSIONS: MRI of the knee joint is increasingly used to study hyper and acute ACL tears thanks to the availability of dedicated units. The MR study of ACL tears is not meant to refer the patients to surgery, which pertains to the physical examination, but it allows to assess lesion severity and to show associated injuries in other knee structures.

[Superparamagnetic iron oxide in the differential diagnosis of focal hepatic lesions using a 0.5-tesla magnetic resonance apparatus]. / Ossido di ferro superparamagnetico nella diagnosi differenziale delle lesioni focali epatiche con apparecchio di risonanza magnetica da 0.5 tesla.

INTRODUCTION: We investigated the efficacy of superparamagnetic iron oxide (SPIO) in the characterization of focal liver lesions on MR images by means of quantitative and qualitative analysis. MATERIAL AND METHODS: We examined 60 patients with at least one focal liver lesion on US images. Conventional T1-weighted spin echo (CSE), proton density and T2-weighted MR images were acquired before and after the injection of a SPIO agent (Endorem, slow infusion, 15 micromoles Fe/kg body weight). A qualitative and a quantitative analysis were performed calculating the contrast enhancement rate in different kinds of lesions; the differences were related to the type of sequence statistically using Student's t-test for coupled samples. RESULTS: Excellent correlation was found with biopsy findings in all but two patients who were false positive for hepatocellular carcinoma (scar on cirrhotic liver). T1-weighted sequences after AMI-25 injection were the most specific ones in hemangioma characterization; PD were the most sensitive sequences in the detection and characterization of liver metastases. T2-weighted sequences were helpful only in the detection of focal liver lesions but they were not specific. CONCLUSIONS: In conclusion, SPIO-enhanced MRI is an excellent imaging tool for the differential diagnosis of focal liver lesions, with a good specificity for the differential diagnosis of hemangioma and metastasis. It is also helpful to distinguish benign from malignant lesions.

Joint impingement syndrome: clinical features.

Joint impingement is a painful syndrome caused by the friction of joint tissues, which is both the cause and the effect of altered joint biomechanics. From the anatomical and clinical viewpoints, these syndromes are classified as bone impingement, soft tissue impingement and entrapment neuropathy, depending on what joint portion impinges on the others. We considered the most important impingement syndromes of the upper and the lower limbs from the clinical viewpoint. As for the upper limb, supraspinatus impingement is a frequent cause of shoulder pain in both athletes and the normal population; the painful subacromial arch is a typical sign of the rotator cuff impingement syndrome and of outlet and non-outlet impingement as well. As for the elbow, we considered both medial and lateral impingement. The carpal tunnel syndrome is the most common peripheral entrapment neuropathy of the upper limb; it is caused by compression of the median nerve at the wrist. We considered the main causes of carpal tunnel narrowing and the relative clinical findings. As for the lower limb, we considered the iliotibial band friction syndrome, which is the most common overuse syndrome of the knee and the ankle impingement syndrome. The latter includes anterolateral impingement (with chronic anterolateral and lateral pain and ankle instability), sinus tarsi impingement, anterior impingement (with pain during foot dorsiflection and posterior impingement. The tarsal tunnel syndrome is the most important ankle entrapment neuropathy causing burn pain and paresthesias in the toes and sole of the foot.

Ankle impingement syndromes.

The ankle impingement syndrome is a frequent condition in both athletes and the normal population. We investigated this painful syndrome from both a clinical and a diagnostic viewpoint. Depending on what ankle tissue impinges on the other, it is possible to distinguish bone impingement, soft tissue impingement and peripheral nerve entrapment. For each of these pathologic conditions we investigated the diagnostic role of conventional radiography, Computed Tomography and Magnetic Resonance Imaging. The evidence of osteophytes, exostosis and presence of the os trigonum on plain films make clinical diagnosis easy in both anterior and posterior bone impingement. CT can provide useful information about the component of the posterior ankle. MRI always adds important information about chondral or subchondral bone injuries, synovial reaction and adjacent soft tissue involvement. The anterolateral impingement syndrome is caused by repeated injuries in plantar flexion and ankle intrarotation. MRI well detects the meniscoid injury thanks to high contrast sequences; it can also distinguish this syndrome from painful chondral and/or bony lesions at this level. MRI is also the method of choice to study sinus tarsi impingement, especially thanks to fat suppression sequences which increase MR diagnostic capabilities in this important anatomic area. Deep peroneal nerve entrapment, the medial plantar nerve entrapment syndrome and the tarsal tunnel syndrome are the most important entrapment neuropathies of the ankle. US and MRI are very useful to study the tendon and soft tissue abnormalities causing the anterior tarsal tunnel syndrome. CT and particularly MRI can easily detect many pathologic conditions causing the medial plantar nerve entrapment and the tarsal tunnel syndromes.