Girolamo Crisi

Increased Functional Connectivity in the Default Mode Network in Mild Cognitive Impairment: A Maladaptive Compensatory Mechanism Associated with Poor Semantic Memory Performance

Semantic memory decline and changes of default mode network (DMN) connectivity have been reported in mild cognitive impairment (MCI). Only a few studies, however, have investigated the role of changes of activity in the DMN on semantic memory in this clinical condition. The present study aimed to investigate more extensively the relationship between semantic memory impairment and DMN intrinsic connectivity in MCI. Twenty-one MCI patients and 21 healthy elderly controls matched for demographic variables took part in this study. All participants underwent a comprehensive semantic battery including tasks of category fluency, visual naming and naming from definition for objects, actions and famous people, word-association for early and late acquired words and reading. A subgroup of the original sample (16 MCI patients and 20 healthy elderly controls) was also scanned with resting state functional magnetic resonance imaging and DMN connectivity was estimated using a seed-based approach. Compared with healthy elderly, patients showed an extensive semantic memory decline in category fluency, visual naming, naming from definition, words-association, and reading tasks. Patients presented increased DMN connectivity between the medial prefrontal regions and the posterior cingulate and between the posterior cingulate and the parahippocampus and anterior hippocampus. MCI patients also showed a significant negative correlation of medial prefrontal gyrus connectivity with parahippocampus and posterior hippocampus and visual naming performance. Our findings suggest that increasing DMN connectivity may contribute to semantic memory deficits in MCI, specifically in visual naming. Increased DMN connectivity with posterior cingulate and medio-temporal regions seems to represent a maladaptive reorganization of brain functions in MCI, which detrimentally contributes to cognitive impairment in this clinical population.

Visuospatial Memory and Neuroimaging Correlates in Mild Cognitive Impairment

Spatial abilities decline in normal aging and decrease faster and earlier in Alzheimers disease (AD), but these deficits are under investigated. The main goals of this study were to assess visuospatial memory abilities in mild cognitive impairment (MCI), in order to verify whether these tasks might be valid as the standard cognitive test to differentiate MCI individuals from normal controls and to investigate the brain structural correlates of visuospatial deficits. Twenty MCI patients and fourteen healthy elderly controls underwent an experimental visuospatial battery, which also included self-rating spatial questionnaires, and structural MRI brain imaging. Compared to healthy elderly controls, MCI patients scored significantly worse in almost all visuospatial tasks. ROC analysis showed that visuospatial tasks had an elevated discriminant power between groups (AUC >0.90). Voxel-based morphometry analysis, compared to controls, disclosed a higher level of atrophy in frontal and medio-temporal regions and a different pattern of correlation between grey matter values and visuospatial performance, with wider distributed areas of the occipital and middle temporal cortex in the map and route learning. This study indicates that visuospatial memory tests are valid tools in completing the diagnostic evaluation of MCI.

Central Facial Palsy Revisited: A Clinical-Radiological Study

We investigated the pattern of volitional facial motor deficits in acute stroke patients. We assessed the strength of single facial movements and correlated it to the site of infarct classified on computed tomography scans. Exclusion criteria were previous stroke, cerebral hemorrhage, and subcortical stroke. Results showed that weakness in eyelid closure was associated with anterior cerebral artery (ACA) stroke. Weakness in lip opening was associated with middle cerebral artery (MCA) stroke. We suggest that sparing of upper facial movements in MCA stroke is due to the presence of an upper face motor representation in both the MCA and ACA territories. ANN NEUROL 2010;68:404–408

Bilateral cerebellopontine angle lipomas

Cerebellopontine angle (CPA) lipomas are extremely rare lesions and usually unilateral. We describe a case of a 36-year-old man with bilateral aural fullness that was discovered to have bilateral CPA lipomas associated with an abnormal hindbrain segmentation appearance. The patient was evaluated with 3.0T magnetic resonance imaging (MRI) system. MRI demonstrated the presence of bilateral CPA masses partially extending into the internal auditory canals. These lesions were hyperintense on both T1- and T2 weighted images. Facial and vestibulo-cochlear nerves together with tortuous vascular structures and fibro-connective septa were identified on T2-weighted 3D Fast Imaging Employing Steady-state Acquisition (FIESTA) sequences as areas of lower intensity coursing through the masses. Gadolinium administration yielded no enhancement. Conservative management was adopted.

Goldenhar syndrome associated with contralateral agenesis of the internal carotid artery.

Congenital absence of the internal carotid artery (ICA) is an extremely rare vascular anomaly. Aplasia and displacement of the horizontal portion of the petrous carotid artery have been described in a patient with mandibulofacial dysostosis. To the best of our knowledge, the association between Goldenhar syndrome and ipsilateral ICA agenesis has emerged only in one case documented in the medical literature to date. We describe here a case that illustrates the association of Goldenhar syndrome with contralateral agenesis of the ICA incidentally detected on brain magnetic resonance imaging and subsequently confirmed on magnetic resonance angiography and high resolution computed tomography.Functional outcome following emergent intra-arterial thrombectomy is variable and likely reflects the heterogeneous characteristics of acute stroke patients. The aims of our study were (1) to study which pre-treatment variables correlate with functional outcome and (2) to devise a tool which would reliably predict outcome. Prospective data of patients treated with intra-arterial mechanical thrombectomy in our institution between 2010 and 2012 were collected. A preliminary univariate analysis of baseline variables was performed and data outliers were identified by constructing scatter and box plots. Systematic bivariate analysis was then carried out using a linear regression model and the individual contributing weights of the variables to outcome calculated. The B and constant values from the regression were used to construct a predictive formula. Fifty-seven patients, 35 males (61.4%) and 22 females (38.6%) with a mean age of 62.3 years (range 26-87) were included in the cohort. Statistical correlations of baseline variables and functional outcome showed that age, National Institutes of Health Stroke Scale at presentation and CT leptomeningeal collaterals were strongly correlated (p<0.01), and were later included in the linear regression model. A tool was devised from the regression formula combining weighted inputs of the three variables. Regression statistics and residual analysis were then performed to assess the accuracy and reliability of the proposed tool. The proposed tool is easy to use and reliably predicts functional outcome prior to endovascular therapy. It may help clinical decision-making in the acute setting and offers tailor-made outcome expectations.

Tapia's syndrome secondary to laterocervical localization of diffuse large cell lymphoma.

The eponym Tapias syndrome indicates an associated unilateral vocal cord and tongue paralysis secondary to a peripheral involvement of the recurrent laryngeal branch and the hypoglossal nerve. Although mainly observed as a complication of surgery or anaesthesia, it can rarely occur secondary to infectious or neoplastic causes. We are presenting a case of a teen-ager with Tapias syndrome who had been seeking medical assistance for episodes of loss of consciousness and was diagnosed with a high-grade peripheral B-cell lymphoma, an association not previously described. This syndrome should be remembered even outside the surgical contest for its highly localising value.

A painful stiff neck following an ear, nose, and throat surgical procedure: case report.

Grisel syndrome is a rare, nontraumatic atlantoaxial subluxation, typical of developmental ages and characterized by head flexion/rotation and painful fixation. Neurological symptoms may occur. It is secondary to head/neck infections and ear, nose, and throat surgery (adenoidectomy, tonsillectomy, and mastoidectomy). Here, we report the case of a child who presented a painful stiff neck following an adenotonsillectomy, with imaging evidencing an atlantoaxial subluxation. The child showed improvement in his condition following a conservative treatment with antibiotics, anti-inflammatory, and analgesic therapy and cervical collar. We believe it is of great significance for clinicians taking into account this peculiar condition in the differential diagnosis of a stiff neck in pediatric patients, thus avoiding misdiagnosis and delays. Indeed, its diagnosis is mainly based on a focused anamnesis associated with the detection of the typical neuroradiological findings.

Unilateral ectopic parotid gland in CHARGE syndrome

Unilateral absence of a parotid gland at the expected location is an extremely rare condition with only a few cases reported in the medical literature and, to our knowledge, never previously described in association with CHARGE syndrome (Coloboma of the eye, Heart defects, Atresia of the choanae, Retardation of growth and/or development, Genital and/or urinary abnormalities, and Ear abnormalities and deafness). Although this entity is usually associated with a complex constellation of anomalies, additional findings have been described, including cranial nerve dysfunction (VII, VIII, IX and X). We present a case that illustrates the association of CHARGE syndrome with absence of parotid gland at normal location with ectopic parotid tissue lateral to masseter muscle, incidentally detected on brain MRI and subsequently confirmed on neck MRI.

Pseudotumoural Hemicerebellitis: Conventional MR Imaging and MR Spectroscopy Evolution: A Case Report

Acute cerebellitis is an inflammatory process commonly involving both cerebellar hemispheres. Bilateral cerebellar hemispheres involvement is the most common finding. It typically occurs as a primary infectious, post-infectious or post-vaccination disorder, but is also a disease entity with heterogeneous pathogenesis including paraneoplasia. Acute cerebellitis is usually a benign, self-limiting and rarely fatal disease. Typically, cerebellar atrophy is a late consequence of the syndrome. We describe the radiological features of a case of pseudotumoural hemicerebellitis with emphasis on MRI and spectroscopy findings as non-invasive diagnostic tools to avoid unnecessary surgical procedures.

Bilateral surgical damage of the central tegmental tract resulting in bilateral hypertrophic olivary degeneration: An MRI case report

Hypertrophic olivary degeneration (HOD) is a rare trans-synaptic neuronal degeneration of the inferior olivary nucleus caused by an injury to the dentato-rubro-olivary connection, also known as Guillain-Mollaret triangle. It leads to hypertrophy of the affected nucleus rather than atrophy and is characterized by hyperintensity on T2-weighted images. Unilateral and bilateral cases are described. We present a case of a 70-year-old patient affected by a tumor inside the fourth ventricle who suffered from diplopia and right seventh cranial nerve palsy. He underwent surgery and developed left seventh cranial nerve palsy. Three months after resection, magnetic resonance imaging revealed the appearance of bilateral HOD. This is the first report of bilateral HOD occurrence after surgical bilateral damage of the rubro-olivary fibers running in central tegmental tracts.