Role of Functional Imaging Techniques to Assess Motor and Language Cortical Plasticity in Glioma Patients: A Systematic Review.

Cerebral plasticity is the ability of the central nervous system to reorganize itself in response to different injuries. The reshaping of functional areas is a crucial mechanism to compensate for damaged function. It is acknowledged that functional remodeling of cortical areas may occur also in glioma patients. Principal limits of previous investigations on cortical plasticity of motor and language functions included scarce reports of longitudinal evaluations and limited sample sizes. This systematic review is aimed at elucidating cortical brain plasticity for motor and language functions, in adult glioma patients, by means of preoperative and intraoperative mapping techniques. We systematically reviewed the literature for prospective studies, assessing cortical plasticity of motor and language functions in low-grade and high-grade gliomas. Eight longitudinal studies investigated cortical plasticity, evaluated by motor and language task-based functional MRI (fMRI), motor navigated transcranial magnetic stimulation (n-TMS), and intraoperative mapping with cortical direct electrocortical stimulation (DES) of language and motor function. Motor function reorganization appeared relatively limited and mostly characterized by intrahemispheric functional changes, including secondary motor cortices. On the other hand, a high level of functional reshaping was found for language function in DES studies. Occurrence of cortical functional reorganization of language function was described focusing on the intrahemispheric recruitment of perilesional areas. However, the association between these functional patterns and recovery of motor and language deficits still remains partially clear. A number of relevant methodological issues possibly affecting the finding generalization emerged, such as the complexity of plasticity outcome measures and the lack of large longitudinal studies. Future studies are required to further confirm these evidences on cortical plasticity in larger samples, combining both functional imaging and intraoperative mapping techniques in longitudinally evaluations.

Efficacy of a new delivery system based on solid lipid microparticles for the oral administration of the non-conventional antioxidant IAC on a diabetes mouse model.

PURPOSE: We previously showed the positive effects of the new antioxidant molecule bis(1-hydroxy-2,2,6,6-tetramethyl-4-piperidinyl)-decandioate (IAC) in reducing basal hyperglycaemia and relieving glucose intolerance in a diabetes model. However, the chemical properties of IAC did not allow an efficient oral administration, thus representing the main failing of that study. Here, we tested the effect of a new oral delivery system based on solid lipid microparticles (SLMs) in a diabetes mouse model. METHODS: The diabetes model was induced in C57B1/6J mice using streptozotocin and nicotinamide. Only the animals that overcame the glycaemic threshold of 180 mg/dL were enrolled in the study. Diabetic animals were then randomly assigned to 4 groups (n = 9) and treated once a day for 5 consecutive weeks with IAC (50, 100, and 150 mg/kg b.w.). The control group was composed of (n = 7) healthy mice that received only the vehicle. Glucose level was weekly monitored during the treatment period and up to 3 weeks after the suspension of the treatment. Glucose tolerance and insulin-resistance test were carried out. RESULTS: Our results showed that SLMs maintained the IAC effect in reducing basal hyperglycaemia as well as improving the insulin sensitivity and glucose tolerance. CONCLUSION: The present study confirms that SLMs are promising drug carriers, which allow the oral administration of IAC ensuring its therapeutic efficacy. The concrete possibility to administer IAC per os represents a significant breakthrough in the putative consideration of this multi-radical scavenger in the diabetes therapeutic approach.

Whole-body MRI with diffusion-weighted imaging: a valuable alternative to contrast-enhanced CT for initial staging of aggressive lymphoma.

AIM: To compare the accuracy of whole-body magnetic resonance imaging (Wb-MRI) with diffusion-weighted imaging (DWI) to that of contrast-enhanced computed tomography (CE-CT) and 2-[(18)F]-fluoro-2-deoxy-d-glucose ((18)F-FDG) positron-emission tomography co-registered with low dose-CT (PET-CT) in defining lymphoma disease stage. MATERIALS AND METHODS: From February 2010 to May 2014, 41 lymphoma patients underwent Wb-MRI-DWI, CE-CT, and (18)F-FDG PET-CT. Histological subtypes included aggressive B-cell (n=11), follicular (n=13), mantle cell (n=3), and Hodgkin's (n=14) lymphoma. To compare the procedures, the reference standard (RS) assessment was defined by combining the results from (18)F-FDG PET-CT, CE-CT, and bone marrow (BM) histology, modifications after therapy, and histological re-assessments of uncertain lesions. RESULTS: Among 1025 nodal sites, 217 had disease involvement according to the RS. CE-CT yielded 23 false-negative and 11 false-positive errors. Wb-MRI-DWI failed to recognise 17 localisations and had six false-positive errors; (18)F-FDG PET-CT had no errors. Among 458 extranodal sites, 37 were positive according to the RS. (18)F-FDG PET-CT yielded four false-negative and two false-positive results. CE-CT yielded 17 false-negative errors. Wb-MRI-DWI yielded a single false-negative error. Wb-MRI-DWI was the most reliable imaging technique for BM evaluation. Considering each procedure alone, the final stage would have been missed in four cases using (18)F-FDG PET-CT, 12 cases using CE-CT, and none using Wb-MRI-DWI. CONCLUSION: The present data support Wb-MRI-DWI as a sensitive and specific imaging technique for lymphoma evaluation, supporting its use in place of CE-CT for staging.

Supratracheal laryngectomy: current indications and contraindications.

Cancer of the larynx in the intermediate/advanced stage still presents a major challenge in terms of controlling the disease and preserving the organ. Supratracheal partial laryngectomy (STPL) has been described as a function-sparing surgical procedure for laryngeal cancer with sub-glottic extension. The aim of the present multi-institutional study was to focus on the indications and contraindications, both local and general, for this type of surgery based on the long-term oncological and functional results. We analysed the clinical outcomes of 142 patients with laryngeal cancer staged pT2-pT4a who underwent STPL. Five-year overall survival (OS), disease-specific survival (DSS), disease-free survival (DFS) and loco-regional control (LRC) rates were: glottic pT2 [71.4%, 95.2%, 76.0%, 76.0%], glottic-transglottic pT3 [85.3%, 91.1%, 86.4%, 88.7%], and pT4a [73.2%, 88.1%, 52.7%, 60.7%], respectively. DFS and LRC prevalences at 5 years were greatly affected by pT4a staging. Five-year laryngeal function preservation (LFP) and laryngectomy free survival (LFS) were: glottic pT2 [90.9%, 95.2%], glottic-transglottic pT3 [84.4%, 93.1%], and pT4a [63.7%, 75.5%], respectively, being affected by pT staging and age 65 ≥ years (LFP 54.1%). As a result of Type III open horizontal partial laryngectomies (OPHLs) (supratracheal laryngectomies), the typical subsites of local failure inside the larynx were the mucosa at the passage between the remnant larynx and trachea, the mucosa at the level of the posterior commissure and the contralateral cricoarytenoid unit as well as outside the larynx at the level of the outer surface of the remnant larynx. For patients with glottic or transglottic tumours and with sub-glottic extension, the choice of STPL can be considered to be effective, not only in prognostic terms, but also in terms of functional results.

Computer-aided cognitive rehabilitation improves cognitive performances and induces brain functional connectivity changes in relapsing remitting multiple sclerosis patients: an exploratory study.

To better understand the effects of short-term computer-based cognitive rehabilitation (cCR) on cognitive performances and default mode network (DMN) intrinsic functional connectivity (FC) in cognitively impaired relapsing remitting (RR) multiple sclerosis (MS) patients. Eighteen cognitively impaired RRMS patients underwent neuropsychological evaluation by the Rao's brief repeatable battery and resting-state functional magnetic resonance imaging to evaluate FC of the DMN before and after a short-term (8 weeks, twice a week) cCR. A control group of 14 cognitively impaired RRMS patients was assigned to an aspecific cognitive training (aCT), and underwent the same study protocol. Correlations between DMN and cognitive performances were also tested. After cCR, there was a significant improvement of the following tests: SDMT (p < 0.01), PASAT 3" (p < 0.00), PASAT 2" (p < 0.03), SRT-D (p < 0.02), and 10/36 SPART-D (p < 0.04); as well as a significant increase of the FC of the DMN in the posterior cingulate cortex (PCC) and bilateral inferior parietal cortex (IPC). After cCR, a significant negative correlation between Stroop Color-Word Interference Test and FC in the PCC emerged. After aCT, the control group did not show any significant effect either on FC or neuropsychological tests. No significant differences were found in brain volumes and lesion load in both groups when comparing data acquired at baseline and after cCR or aCT. In cognitively impaired RRMS patients, cCR improves cognitive performances (i.e., processing speed and visual and verbal sustained memory), and increases FC in the PCC and IPC of the DMN. This exploratory study suggests that cCR may induce adaptive cortical reorganization favoring better cognitive performances, thus strengthening the value of cognitive exercise in the general perspective of building either cognitive or brain reserve.

Widespread microstructural white matter involvement in amyotrophic lateral sclerosis: a whole-brain DTI study.

BACKGROUND AND PURPOSE: The extensive application of advanced MR imaging techniques to the study of ALS has undoubtedly improved our knowledge of disease pathophysiology, even if the actual spread of the neurodegenerative process throughout the central nervous system is not fully understood. The present study aimed to detect WM patterns of microstructural abnormalities to better investigate the pathologic process in ALS, within but also beyond CSTs, in a whole-brain analysis. MATERIALS AND METHODS: DTI was performed in 19 patients with ALS and 20 matched healthy controls, by using whole-brain TBSS and VOI analyses. RESULTS: We observed a significant decrease of FA in the body of CC of the ALS group (P < .05). At the VOI level, both FA decrease and RD increase in the body of CC significantly correlated with the UMN score (P = .003 and P = .02). Additionally, significant voxelwise positive correlations between FA and the ALSFRS-R were detected in the WM tracts underneath the left premotor cortex (P < .05). CONCLUSIONS: The correlations between reduction of FA and increase of RD in the body of CC with the UMN score indicate that the WM degeneration in the CC is strictly related to the ALS pyramidal impairment, while the correlation between FA and ALSFRS-R in the associative tracts underneath the left premotor cortex might reflect the progressive spread of the disease from the motor toward the extramotor areas.

Spontaneous regression of dilated virchow-robin spaces. A case report.

We describe a 28-year-old woman with a dilated perivascular spaces in the right pre-rolandic district. The purpose of this article is to provide an in-depth overview of the MR imaging features of VR spaces and to describe magnetic resonance imaging evidence of complete regression of dilated perivascular spaces (2).

Giant dilatations of virchow-robin spaces in the midbrain. MRI aspects and review of the literature.

Virchow-Robin spaces are lesions often seen in the brain parenchyma but their etiopathogenesis remains unsettled. Giant Virchow-Robin spaces placed in the midbrain are extremely rare. We describe three patients with a diagnosis of giant Virchow-Robin spaces in the midbrain, and their clinical and radiologic findings. We reviewed the literature in terms of the etiopathology, anatomic and radiologic appearance and differential diagnosis of the giant Virchow-Robin spaces. The diagno-stic role of the high Tesla magnetic resonance devices and new sequences techniques such as three dimensional isotropic acquisition and diffusion tensor imaging were also evaluated in this case series.

Paget's Disease. A Case Report.

Paget's disease (PD) is a common focal progressive osteometabolic disorder characterised by a disturbance in bone modelling and remodelling, because of an increase in osteoblastic and osteoclastic activity. It is a condition of unknown aetiology affecting approximately 3% of the population over 40 years of age and, approximately 10% of those over the age of 85 years. It is most common in Northern Europe and Australia and is rare in Asia and Africa. We describe the case of a 71-year-old man diagnosed with PD confined to the sacrum. After laboratory test, an imaging study with radiography, scintigraphy, computed tomography (CT) and magnetic resonance imaging (MRI) was performed disclosing findings compatible with Paget's disease in middle pathologic phase. The diagnosis was confirmed at biopsy. The structural modification of the sacrum with spongiosa rarefaction, thickening of bone and intact bone cortical, confirmed by CT, are tipical of an intermediate phase of PD. This was also supported by signal MRI changes showing substitution of the red by the fat medulla, visualized by FS sequences. Once the treatment for the bone disease was established, the patient no longer complained of pain. Special attention should be paid to male and elderly patients with pain in the lumbar spine because of the potential risk cancer development (21). The radiologist must be attentive to the possible presentations and complications of PD, even in uncommon sites, trying whenever possible to correlate the radiological features with the patient's clinical symptoms.

Spontaneous regression of syringomyelia in a young patient with Chiari type I malformation.

Syringomyelia is a disorder in which a cyst or cavity forms within the spinal cord. This cyst, called syrinx, can expand and elongate over time, destroying the spinal cord. We describe the case of a young patient with partial spontaneous regression of syringomyelia in Chiari I malformation, confirmed by magnetic resonance imaging three years after the diagnosis. During this period the patient did not experience any clinical symptoms. Although described in literature, spontaneous regression is an unusual event and very few cases have been reported. This case report supports the belief that conservative management together with both clinical and imaging periodic controls should be preferred in stable mild-symptomatic patients.

Interictal cortical reorganization in episodic migraine without aura: an event-related fMRI study during parametric trigeminal nociceptive stimulation.

The aim of our study was to explore the pain processing network in patients with migraine during trigeminal nociceptive stimulation. Sixteen patients with episodic migraine without aura and 16 healthy controls performed functional magnetic resonance imaging during thermal stimuli (at 41, 51 and 53°C). Patients with migraine showed a greater activation in the perigenual part of anterior cingulate cortex at 51°C and less activation in the bilateral somatosensory cortex at 53°C compared to healthy controls. There were no differences in experimental pain perception between groups. Our findings demonstrate a functional reorganization of cerebral areas known to be involved in pain processing in patients with migraine.

Combined first-stage hepatectomy and colorectal resection in a two-stage hepatectomy strategy for bilobar synchronous liver metastases.

BACKGROUND: This study assessed the feasibility and outcomes of combined colorectal and hepatic resection as the first step of two-stage hepatectomy in patients with bilobar synchronous colorectal liver metastases. METHODS: All patients with bilobar synchronous colorectal liver metastases who were considered for two-stage hepatectomy, combining resection of the primary tumour with the first stage of hepatectomy, between 2000 and 2008 were selected from a prospectively collected database at two institutions. Data were analysed retrospectively on an intention-to-treat basis. RESULTS: Thirty-three patients were studied. Twenty patients received neoadjuvant chemotherapy. Combined colorectal resection and clearance of left-sided liver metastases was the first-stage procedure in all but one patient, in whom right clearance was performed. In 17 patients right portal vein ligation was undertaken at the same time. No patient died. Two patients had anastomotic leakage. Interval chemotherapy was given to 25 patients, five of whom also had percutaneous portal vein embolization. Twenty-five patients had the second-stage hepatectomy, but not eight patients with disease progression. There was one postoperative death after the second stage, and eight patients experienced morbidity. Median follow-up from the first stage was 28.7 months. Overall and disease-free survival rates for patients who completed the procedure were 80 and 44 per cent respectively at 3 years, and 48 and 22 per cent at 5 years. CONCLUSION: In patients with bilobar synchronous colorectal liver metastases who are candidates for two-stage hepatectomy, combined resection of the primary tumour and first-stage hepatectomy reduces the number of procedures, optimizes chemotherapy administration and may improve outcome.

Non-Alcoholic Wernicke Encephalopathy: MR Imaging and Review of the Literature.

We describe a patient with non-alcoholic Wernicke's encephalopathy caused by long-term parenteral nutrition. The diagnosis is based on clinical and magnetic resonance findings. We also reviewed the literature review in typical and atypical findings at MR examination.

Hippocampal asymmetry with hippocampal sulcus remnants in a patient with mild cognitive impairment. A case report.

A 65-year-old woman underwent MRI for a mild cognitive impairment (MCI) at Mini-Mental State Examination (MMSE). MRI showed hippocampal sulcus remnants bilaterally, although they were larger on the right, and left hippocampal atrophy with increased left fimbriosubicular distance (right side: 1.2 mm; left side: 2.0 mm). The meaning of these findings in relation to clinical aspects is discussed and reviewed according to data from the literature.

Spontaneous resolution of eosinophilic granuloma in a patient with a psychotic disorder.

A 16-year-old female who manifested psychotic symptoms underwent CT and MRI for the evaluation of an incidentally discovered asymptomatic palpable mass of the right occipital region of the skull. The correlation between clinical and radiological data and biopsy data led to the diagnosis of eosinophilic granuloma. The radiological finding is discussed and reviewed in relation to clinical aspects and literature data.

Role of Magnetic Resonance Imaging in Duane's Retraction Syndrome: Presence of the Abducens Nerve Depending on Type. A Clinical-Anatomical Study.

This study correlated anatomical findings and clinical evidence in Duane's Retraction Syndrome using brain MRI. The study included 11 patients with different types of Duane's Retraction Syndrome (DRS). Each patient underwent brain MRI. The VI(th) nerve was absent in all patients with DRS-I, present in all patients with DRS-II, while findings varied in patients with DRS-III. Our study confirms the literature on the usefulness of brain MRI in diagnosis of Duane's Retraction Syndrome in children.

DWI Reversibility after Intra-Arterial Thrombolysis. A Case Report and Literature Review.

We report our case and review the literature on reversal DWI lesions, ADC thresholds and correlation between DWI lesion and outcome measured with clinical scales. A 30-years old woman was admitted to our hospital 18 hours after stroke onset. Considering the absence of alterations on CT and the worsening of symptomatology, the patient underwent MRI, which showed a slightly hyperintense signal in FLAIR images in the left portion of the pons and midbrain and a more evident bilateral DWI hyperintensity of the pons. The patient was treated with mechanical and pharmacological intra-arterial thrombolysis. The patient showed a rapid improvement of symptoms. Two weeks after the treatment her clinical conditions were characterized by a residual right hemiparesis and complete recovery of right motility, respiratory and swallowing difficulties. MR examination demonstrated a slight signal alteration of the pons left hemiportion and a disappearance of the mesencephalic signal alteration and of the right portion of the pons. DWI lesions represent irreversibly damaged tissue but new evidence suggests that DWI lesions may be reversible, especially with reperfusion, by now well demonstrated in animal models. Therefore acute DWI lesions probably contain not only irreversibly injured tissue but also parts of the penumbra. The debate on the capability of ADC maps to discriminate irreversibly from reversibly damaged tissue is a matter of controversy. ADC values in human stoke are not an independent indicator of tissue viability. The use of thresholds may improve reproducibility but not validity.

Does the default-mode functional connectivity of the brain correlate with working-memory performances?

The "default-mode" network is an ensemble of cortical regions that are typically deactivated during demanding cognitive tasks in functional magnetic resonance imaging (fMRI) studies. Using functional connectivity analysis, this network can be studied as a "stand-alone" brain system whose functional role is supposed to consist in the dynamic control of intrinsic processing activities like attention focusing and task-unrelated thought generation and suppression. Independent component analysis (ICA) is the method of choice for generating a statistical image of the "default-mode" network (DMN) using a task- and seed-independent distributed model of fMRI functional connectivity without prior specification of node region extent and timing of neural activation. We used a standard graded working-memory task (n-back) to induce fMRI changes in the default-mode regions and ICA to evaluate to DMN functional connectivity in nineteen healthy volunteers. Based on the known spatial variability of the ICA-DMN maps with the task difficulty levels, we hypothesized the ICA-DMN may also correlate with the subject performances. We confirmed that the relative extent of the anterior and posterior midline spots within the DMN were oppositely (resp. positively in the anterior and negatively in the posterior cingulate cortex) correlated with the level of task difficulty and found out that the spatial distribution of DMN also correlates with the individual task performances. We conclude that the working-memory function is related to a spatial re-configuration of the DMN functional connectivity, and that the relative involvement of the cingulate regions within the DMN might function as a novel predictor of the working-memory efficiency.

Small animal imaging facility: new perspectives for the radiologist.

In recent years, new technologies have become available for imaging small animals. The use of animal models in basic and preclinical sciences, for example, offers the possibility of testing diagnostic markers and drugs, which is becoming crucial in the success and timeliness of research and is allowing a more efficient approach in defining study objectives and providing many advantages for both clinical research and the pharmaceutical industry. The use of these instruments offers data that are more predictive of the distribution and efficacy of a compound. The mouse, in particular, has become a key animal model system for studying human disease. It offers the possibility of manipulating its genome and producing accurate models for many human disorders, thus resulting in significant progress in understanding pathologenic mechanisms. In neurobiology, the possibility of simulating neurodegenerative diseases has enabled the development and validation of new treatment strategies based on gene therapy or cell grafting. Noninvasive imaging in small living animal models has gained increasing importance in preclinical research, itself becoming an independent specialty. The aim of this article is to review the characteristics of these systems and illustrate their main applications.