Retinal and Cortical Visual Processing Dysfunction in a Case of Mild Cognitive Impairment with Lewy Bodies: A Case Report.

The prodromal stage of Lewy body dementia includes a mild cognitive impairment with visual processing and/or attention-executive deficits. A clinical presentation with progressive visual loss is indeed seldom reported and can be misleading with a posterior cortical atrophy disease. While the neurodegeneration at the occipital cortex can only partially explain the visual disturbances of Lewy body dementia, more recently a retinal dysfunction has been suggested by preliminary optical coherence tomography and autoptic findings. Herein, we present a case of a mild cognitive impairment with Lewy bodies, who presented initially with visual disturbances and signs of both retinal and cortical visual processing dysfunction. A complete neuropsychological, neurophysiological and brain imaging assessment highlighted a prominent ventral visual pathway involvement. This report provides first that the prodromal stage of Lewy body dementia can manifest as a primarily progressive visual loss, second that the involvement of visual pathway, particularly the ventral stream, can be detectable from the retinal to the cortical level.

Neurophysiological Alterations of the Visual Pathway in Posterior Cortical Atrophy: Systematic Review and a Case Series.

Background: The clinical features of posterior cortical atrophy (PCA), a rare condition often caused by Alzheimer's disease, have been recently defined, while little is known about its neurophysiological correlates. Objective: To describe neurophysiological alterations of the visual pathway as assessed using visual field test (VF), visual evoked potentials (VEP), and electroretinogram (ERG) in PCA patients. Methods: Studies reporting VF, VEPs, and ERG in PCA patients were selected according PRISMA method. Of the 323 articles that emerged from the literature, 17 included the outcomes of interest. To these data, we added those derived from a patient cohort enrolled at our clinic. Results: The literature review included 140 patients, half of them (50%) presented with homonymous hemianopia or quadrantanopia. VEPs were available in 4 patients (2 normal findings, 1 decreased amplitude, and 1 increased latency) and ERG in 3 patients (substantially normal findings). Our case series included 6 patients, presenting with homonymous lateral hemianopia in 50% and contralateral cortical atrophy. VEPs showed normal amplitude in 66-83% according to the stimulation check, and increased latency in 67% in absence of myelin damage on MRI. Latency was increased in both eyes in 50% and only on one side in the other 50%. Such alterations were observed in patients with more severe and symmetric atrophy. ERG showed normal findings. Conclusions: Neurophysiological investigations of the visual pathway in PCA are almost absent in literature. Alterations involve both amplitude and latency and can be also monocular. A multiple-point involvement of the optical pathway can be hypothesized.

Cognitive Versus Hemorrhagic Onset in Cerebral Amyloid Angiopathy: Neuroimaging Features.

BACKGROUND: Intracerebral hemorrhage and cognitive decline are typical clinical presentations of cerebral amyloid angiopathy (CAA). OBJECTIVE: To determine whether magnetic resonance imaging (MRI) features differ between CAA with hemorrhagic versus cognitive onset. METHODS: In this retrospective study, sixty-one patients with CAA were classified by onset presentation of the disease: hemorrhage (n = 31) or cognitive decline (n = 30). The two groups were compared for MRI markers of small vessel disease, namely cerebral microbleeds (CMBs), cortical superficial siderosis, white matter hyperintensities (WMHs), enlarged perivascular spaces, cortical microinfarcts, and visual rating scales for cortical atrophy. In the patients with cognitive onset, further exploratory analyses investigated MRI markers according to cerebrospinal fluid (CSF) and neuropsychological profiles. RESULTS: Patients with cognitive onset showed a higher prevalence of CMBs (p < 0.001), particularly in temporal (p = 0.015) and insular (p = 0.002) lobes, and a higher prevalence of WMHs (p = 0.012). Within the cognitive onset group, 12 out of 16 (75%) patients had an Alzheimer's disease (AD) CSF profile but did not differ in MRI markers from those without AD pathology. Patients with cognitive onset displayed a multidomain profile in 16 out of 23 (70%) cases; patients with this profile showed increased WMHs and CMBs in parietal lobes compared with the amnestic group (p = 0.002) and dysexecutive group (p = 0.032), respectively. CONCLUSION: Higher burdens of WMHs and CMBs, especially in temporal and insular lobes, are associated with the cognitive onset of CAA. MRI markers could help to shed light on the clinical heterogeneity of the CAA spectrum and its underlying mechanisms.

Progressive post infectious neurological syndromes with a poor outcome: Long term follow-up and neurofilament light chain quantification.

Postinfectious neurological syndromes (PINS), among which acute disseminated encephalomyelitis (ADEM), are inflammatory and mostly monophasic disorders. We previously reported that PINS patients can show relapses, or even disease progression. Here we describe a cohort of patients with progressive-PINS and >5 years of follow-up, that developed a progressive worsening without radiological/cerebrospinal fluid analysis evidence of inflammation. At onset 5 patients fulfilled diagnostic criteria for ADEM and none for MS. Progression occurred after a median of 22 months from onset (in 4/7 after 1/more relapses), manifesting as ascending tetraparesis with bulbar functions involvement in 5/7. Five/7 patients received high dose steroids and/or IvIG and 6/7 Rituximab(n = 4) and/or cyclophosphamide(n = 2), with no impact on disease progression in 6/7. NfL levels were higher in patients with progressive-PINS compared to monophasic-ADEM (p = 0.023) and healthy controls (p = 0.004). Progression is rare, but possible, in PINS. Immunotherapy seems to be ineffective in these patients, and elevated serum NfL in serum suggest persistent axonal damage.

Vascular Lesions and Brain Atrophy in Alzheimer's, Vascular and Mixed Dementia: An Optimized 3T MRI Protocol Reveals Distinctive Radiological Profiles.

BACKGROUND: Vascular lesions may be a common finding also in Alzheimer's dementia, but their role on cognitive status is uncertain. OBJECTIVE: The study aims to investigate their distribution in patients with Alzheimer's, vascular or mixed dementia and detect any distinctive neuroradiological profiles. METHODS: Seventy-six subjects received a diagnosis of Alzheimer's (AD=32), vascular (VD=26) and mixed (MD=18) dementia. Three independent raters assessed the brain images acquired with an optimized 3T MRI protocol (including (3D FLAIR, T1, SWI, and 2D coronal T2 sequences) using semiquantitative scales for vascular lesions (periventricular lesions (PVL), deep white matter lesions (DWML), deep grey matter lesions (DGML), enlarged perivascular spaces (PVS), and microbleeds (MB)) and brain atrophy (medial temporal atrophy (MTA), posterior atrophy (PA), global cortical atrophy- frontal (GCA-F) and Evans' index). RESULTS: Raters reached a good-to-excellent agreement for all scales (ICC ranging from 0.78-0.96). A greater number of PVL (p<0.001), DWML (p<0.001), DGML (p=0.010), and PVS (p=0.001) was observed in VD compared to AD, while MD showed a significant greater number of PVL (p=0.001), DWML (p=0.002), DGML (p=0.018), and deep and juxtacortical MB (p=0.006 and p<0.001, respectively). Comparing VD and MD, VD showed a higher number of PVS in basal ganglia and centrum semiovale (p=0.040), while MD showed more deep and juxtacortical MB (p=0.042 and p=0.022, respectively). No significant difference was observed in scores of cortical atrophy scales and Evans' index among the three groups. CONCLUSION: The proposed MRI protocol represents a useful advancement in the diagnostic assessment of patients with cognitive impairment by more accurately detecting vascular lesions, mainly microbleeds, without a significant increase in time and resource expenditure. Our findings confirm that white and grey matter lesions predominate in vascular and mixed dementia, whereas deep and juxtacortical microbleeds predominate in mixed dementia, suggesting that cerebral amyloid angiopathy could be the main underlying pathology.

PSEN1 Compound Heterozygous Mutations Associated with Cerebral Amyloid Angiopathy and Cognitive Decline Phenotype.

Cerebral amyloid angiopathy (CAA) is a cerebrovascular disorder caused by the deposition of amyloid beta-peptide (Aß) aggregates. Aß aggregates lead to vessel rupture and intracerebral hemorrhages, detected by magnetic resonance imaging (MRI). Presenile CAA is usually genetically determined by mutations in the amyloid precursor protein (APP) gene. However, mutations after codon 200 in the presenilin 1 (PSEN1) gene have been reported to facilitate CAA onset. Here, we analyzed the genetic bases in a patient of 55 years old affected by CAA and cognitive decline. DNA was isolated and genetic analysis was performed by Next-Generation Sequencing (NGS). RNA was extracted and retro-transcribed to perform segregation analysis by TOPO-TA cloning. WB analysis was carried out to check the impact of the mutations on protein. Two compound heterozygous mutations in PSEN1 exon 10, such as a novel stop-gain mutation (c.1070C > G) and a pathogenic splice variant (c.1129A > T), were found by NGS. Both mutations altered the presenilin 1 protein, truncating its C-terminal portion. This is the first case of CAA and cognitive decline caused by two compound mutations in PSEN1. With this report, we suggest extending the genetic analysis to PSEN1 when cerebral microbleeds are observed by MRI investigation in a patient affected by presenile cognitive decline.

Fulminant inflammatory demyelination presenting as stroke-in-evolution in an elderly subject.

BACKGROUND: Fulminant inflammatory demyelination is a possible presentation of inflammatory demyelinating disorders, thus representing a potential stroke mimic especially in younger patients. AIMS OF THE STUDY: To describe clinical and diagnostic pitfalls in a case of fulminant inflammatory demyelination presenting with stroke-like symptoms in an elderly patient. METHODS: Case report and case-based review of the literature. RESULTS: A 67-year-old woman, who accessed the emergency room as suspect stroke for hyperacute onset of rapidly worsening speech impairment and drowsiness, was later diagnosed with a huge brain inflammatory demyelination. Clinical, laboratory, and neuroimaging tests did not allow to put a more specific diagnosis. Due to the rapidly deteriorating course, she received immunosuppression with benefit. CONCLUSION: This report is meant to highlight the diagnostic challenges connected with fulminant inflammatory demyelination, which sometime can resemble a stroke-in evolution and appear clinically unfitting for inclusion in any specific pathological entities within the broad-spectrum of inflammatory demyelinating disorders.

Differential imaging of atypical demyelinating lesions of the central nervous system.

The detection of atypical and sometimes aggressive or tumefactive demyelinating lesions of the central nervous system often poses difficulties in the differential diagnosis. The clinical presentation is generally aspecific, related to the location and similar to a number of different lesions, including neoplasms and other intracranial lesions with mass effect. CSF analysis may also be inconclusive, especially for lesions presenting as a single mass at onset. As a consequence, a brain biopsy is frequently performed for characterization. Advanced MRI imaging plays an important role in directing the diagnosis, reducing the rate of unnecessary biopsies and allowing a prompt start of therapy that is often crucial, especially in the case of infratentorial lesions. In this review, the main pattern of presentation of atypical inflammatory demyelinating diseases is discussed, with particular attention on the differential diagnosis and how to adequately define the correct etiology.

Multi-parametric qualitative and quantitative MRI assessment as predictor of histological grading in previously treated meningiomas.

PURPOSE: Meningiomas are mainly benign tumors, though a considerable proportion shows aggressive behaviors histologically consistent with atypia/anaplasia. Histopathological grading is usually assessed through invasive procedures, which is not always feasible due to the inaccessibility of the lesion or to treatment contraindications. Therefore, we propose a multi-parametric MRI assessment as a predictor of meningioma histopathological grading. METHODS: Seventy-three patients with 74 histologically proven and previously treated meningiomas were retrospectively enrolled (42 WHO I, 24 WHO II, 8 WHO III) and studied with MRI including T2 TSE, FLAIR, Gradient Echo, DWI, and pre- and post-contrast T1 sequences. Lesion masks were segmented on post-contrast T1 sequences and rigidly registered to ADC maps to extract quantitative parameters from conventional DWI and intravoxel incoherent motion model assessing tumor perfusion. Two expert neuroradiologists assessed morphological features of meningiomas with semi-quantitative scores. RESULTS: Univariate analysis showed different distributions (p < 0.05) of quantitative diffusion parameters (Wilcoxon rank-sum test) and morphological features (Pearson's chi-square; Fisher's exact test) among meningiomas grouped in low-grade (WHO I) and higher grade forms (WHO II/III); the only exception consisted of the tumor-brain interface. A multivariate logistic regression, combining all parameters showing statistical significance in the univariate analysis, allowed discrimination between the groups of meningiomas with high sensitivity (0.968) and specificity (0.925). Heterogeneous contrast enhancement and low ADC were the best independent predictors of atypia and anaplasia. CONCLUSION: Our multi-parametric MRI assessment showed high sensitivity and specificity in predicting histological grading of meningiomas. Such an assessment may be clinically useful in characterizing lesions without histological diagnosis. Key points • When surgery and biopsy are not feasible, parameters obtained from both conventional and diffusion-weighted MRI can predict atypia and anaplasia in meningiomas with high sensitivity and specificity. • Low ADC values and heterogeneous contrast enhancement are the best predictors of higher grade meningioma.

Cranial nerve palsies in patients with hematological malignancies: a case series.

Objectives: Cranial neuropathies (CNs) can be due to a wide spectrum of causes, and the differential diagnosis is particularly challenging in patients with positive history of hematological malignancies, when neoplastic meningitis (NM) must be excluded.Patients and Methods: We retrospectively selected a series of twelve haematological patients with isolated cranial neuropathies (ICNs) or multiple cranial neuropathies (MCNs). among 71 patients that developed neurologic symptoms during different stages of the cancer, between 1 January, 2010 and 31 December, 2017. Brain and cauda equina magnetic resonance imaging (MRI) with gadolinium, cerebrospinal fluid (CSF) analysis, including flow cytometry for cell immunophenotyping and microbiological exams were performed in all patients.Results: Patients developed signs and symptoms of involvement of isolated (n = 11) or multiple (n = 1) cranial nerves, at different stages of the primary disease, and, in 5 of these cases in complete remission after hematopoietic stem cell transplantation. Among the 5 cases that eventually were diagnosed as having NM, cerebrospinal fluid was positive for neoplastic cells in 3, and MRI gadolinium-enhancement was present in 3. The other episodes were attributed to heterogeneous pathologies that were unrelated to meningeal infiltration by neoplastic cells.Conclusions: Our observations confirm that NM in haematological malignancies can yield insidious isolated signs of cranial nerves. Only a multidisciplinary approach allows prompt recognition of these conditions through a challenging process of differential diagnosis, and proper therapies.

Atypical postictal transient subcortical T2 hypointensity in a newly diagnosed diabetic patient with seizures.

Common postictal MRI findings include transient cortical T2 hyperintensity, restricted diffusion, and gyral and/or adjacent leptomeningeal contrast enhancement. In certain uncommon pathological conditions, other signal abnormalities can be present, suggesting a different underlying pathogenic mechanism. We report the case of a 66-year-old man, recently diagnosed with diabetes mellitus type 2, presenting with new-onset visual and auditory hallucinations, "absence" seizures, and repeated peaks of hyperglycaemia without hyperketonaemia or increased serum osmolarity. EEG confirmed epileptic discharges in the right temporal region and MRI showed vast subcortical T2 hypointensity in the right temporal lobe, without any cortical hyperintensity, restricted diffusion, or contrast enhancement. Subcortical signal abnormality and EEG discharges resolved after a month of follow-up, with a small juxtacortical gliotic focus as a sequela. Peaks in hyperglycaemia have been reported to be responsible for T2 hypointense subcortical abnormalities through a proconvulsant mechanism linked to increased ketone body concentrations. Hyperosmolarity and hyperketonaemia were not evident in this case, however, transient accumulation of free radicals that alter the intercellular space can be considered the presumable cause of this finding. In summary, it is important to consider any unusual findings on postictal MRI in order to avoid errors in interpretation.

Bing-Neel Syndrome: Illustrative Cases and Comprehensive Review of the Literature.

The Bing-Neel syndrome is a rare neurological complication of Waldenström's Macroglobulinemia which results from a direct involvement of central nervous system by malignant lymphoplasmacytic cells. The clinical suspicion of Bing-Neel syndrome may be overlooked because neurologic symptoms are heterogeneous, nonspecific and sometimes underhand. A definitive diagnosis of Bing-Neel syndrome can be confidently made using brain and spinal cord magnetic resonance imaging as well as histopathology and/or cerebrospinal fluid analysis to confirm the neoplastic infiltration of central nervous system. The detection in the cerebrospinal fluid of patients with Bing-Neel syndrome of the MYD88 (L265P) somatic mutation, which is highly recurrent in Waldenström's Macroglobulinemia, proved useful for the diagnosis and monitoring of central nervous system involvement. Despite recommendations recently published, there is still no clear consensus on treatment of Bing-Neel syndrome, which includes systemic immunochemotherapy, intrathecal chemotherapy and brain irradiation as possible options. Ibrutinib, a Bruton kinase inhibitor approved for Waldenström's Macroglobulinemia, has been recently added to the therapeutic armamentarium of Bing-Neel syndrome due to its ability to pass the blood-brain barrier. However, prospective clinical trials are eagerly awaited with the aim to define the optimal treatment strategy. Here we describe four illustrative cases of Bing-Neel syndrome diagnosed and treated at our Institution and review the literature on this topic.

Meningeal melanomatosis: a challenge for timely diagnosis.

Neoplastic meningitis is a central nervous system complication that occurs in 3-5% of patients with cancer. Although most commonly seen in patients with disseminated disease, in a small percentage of patients, it may be the initial manifestation of cancer or even primitive in origin. In the absence of cancer history, the diagnosis of neoplastic meningitis may be challenging even for expert neurologists. Prognosis is poor, with a median overall survival of weeks from diagnosis. In the retrospective study herein, we described three cases of meningeal melanomatosis in patients without previous cancer history. The patients were diagnosed with significant delay (17 to 47 weeks from symptom onset) mainly due to the deferral in performing the appropriate testing. Even when the diagnosis was suspected, investigations by MRI, cerebrospinal fluid, or both proved at times unhelpful for confirmation. Prognosis was dismal, with a median survival of 4 weeks after diagnosis. Our observations are a cue to analyze the main pitfalls in the diagnosis of neoplastic meningitis in patients without cancer history and emphasize key elements that may facilitate early diagnosis.

Herpes simplex encephalitis in glioma patients: a challenging diagnosis.

OBJECTIVES: In recent years, herpes simplex encephalitis (HSE) has been reported with increasing frequency in settings of immunosuppression, such as acquired immunodeficiency, transplantation and cancer. As observed, in immunocompromised individuals HSE presents peculiar clinical and paraclinical features, and poorer prognosis. METHODS: Here we describe a retrospective series of seven cases of HSE in patients with high-grade glioma (HGG), collected among three institutions in a 5-year period (during this time, a total of 1750 patients with HGG were treated). RESULTS: Diagnosis of the condition was particularly challenging due to the confounding clinical presentation and the atypical biological findings. As a result, antiviral treatment was started with a sharp delay compared with immunocompetent hosts. Prognosis was poor, with high short-term mortality and severe residual disability in survivors. CONCLUSIONS: The substantial incidence of HSE observed in our centres together with the difficulty in diagnosing the condition suggest that the incidence of this complication may be highly underestimated. The aim of our report is to strengthen the observation of HSE in patients with HGG and outline the key elements that may allow its diagnosis.

Transient global amnesia: hippocampal magnetic resonance imaging abnormalities.

Transient global amnesia (TGA) is an episodic dysfunction of declarative memory that usually resolves within 12 hours and whose underlying pathophysiological mechanisms are still unclear. Recent studies, on the basis of transient focal high-signal abnormalities in the hippocampus on diffusion-weighted imaging (DWI), suggest involvement of memory circuits in the temporo-mesial region. Out of a total of 65 patients presenting with acute or subacute TGA between May 2004 and May 2008, we retrospectively analysed 21 in whom a DWI sequence was performed. Five patients showed a focal hippocampal signal alteration both on DWI and on conventional T2; this alteration was no longer detectable on follow-up MRI two months later. The presence of transient DWI and T2 alterations in the hippocampal formation suggests that TGA could have a multifactorial, non-vascular aetiology. The presence of local susceptibility to neuronal metabolic stress emerges as a likely hypothesis.