Posterior cortical atrophy

OBJECTIVE: Women with a history of preeclampsia are at an increased risk of hypertension and structural brain changes. However, the combined effect of both preeclampsia and late-life hypertension on brain structural changes is not known and was investigated in this study. METHODS: Participants were identified from the population-based Rochester Epidemiology Project cohort. Four groups of women were recruited and investigated in this study: first, women with a history of normotensive pregnancy who have late-life hypertension (n = 8, median age = 62), second, women with a history of normotensive pregnancy who do not have late-life hypertension (n = 32, median age = 59), third, women with a history of preeclampsia who have late-life hypertension (n = 24, median age = 60), and fourth, women with a history of preeclampsia who do not have late-life hypertension (n = 16, median age = 57)...

A prospective longitudinal evaluation of 12 patients over a 16-year interval using clinical neurological and imaging data to determine whether posterior cortical atrophy syndrome (PCA) related to early-onset Alzheimer disease (AD) and to examine its natural history. Our 12 patients had a median age of onset of 56 years (range, 48 to 63 y) and were followed for a median of 6 years (range, 3 to 9 y). Patients either presented with complex visual phenomena or developed them with time. Six patients underwent flurodeoxyglucose and Pittsburgh investigational compound B imaging which showed a mismatch between metabolic activity and amyloid deposition with reduced metabolism in parieto-occipital regions on flurodeoxyglucose positron emission tomography and diffuse neocortical uptake of amyloid without occipital predominance...

Non-amnestic Alzheimer disease (AD) variants, including posterior cortical atrophy (PCA) and logopenic variant of primary progressive aphasia (lvPPA), differ in distributions of tau aggregates and neurodegeneration compared to amnestic AD. We evaluated whether (18)F-flortaucipir (also called (18)F-AV-1451) Positron Emission Tomography (PET), targeting tau aggregates, detects these differences and compared this to magnetic resonance imaging (MRI) measures of gray matter (GM) atrophy. Methods: 5 PCA, 4 lvPPA, 6 age-matched AD, and 6 control subjects underwent (18)F-flortaucipir PET and MRI...

RATIONALE: Megalophthalmos anterior is a rare, bilateral, nonprogressive, hereditary, congenital disorder, characterized by the enlargement of all anterior segment structures of the eye, with megalocornea, iris atrophy, and zonular abnormalities commonly found. Usually almost asymptomatic in young patients, with most complaints concerning blurred vision due to the common corneal astigmatism, it might in time lead to several complications including premature cataract formation and pigmentary glaucoma...

BACKGROUND: The reconstruction of alveolar ridges for implant placement is still a challenging surgical procedure, especially in the case of extensive vertical and horizontal bone atrophy. OBJECTIVE: The objective of the present study was to evaluate the quantity and quality of newly regenerated bone; clinically by means of direct clinical measuring, ridges augmented by autogenous cortical bone associated with autogenous particulate bone graft in the posterior lower jaw defect...

BACKGROUND: The rate of disease progression differs among patients with degenerative cerebellar ataxia. The uncertain natural course in individual patients hinders clinical trials of promising treatments. In this study, we analyzed atrophy changes in brain structures with cluster analysis to find sub-groups of patients with homogenous symptom progression in a broad spectrum of degenerative cerebellar ataxias. METHODS: We examined 48 patients including 21 cases of spinocerebellar ataxia (SCA), 17 cases of the cerebellar type of multiple system atrophy (MSA-C), and 10 cases of cortical cerebellar ataxia (CCA)...

BACKGROUND/AIMS: Prior studies of late-onset Alzheimer disease (AD) have reported that cerebrospinal fluid (CSF) tau levels correlate with hippocampal/medial temporal lobe atrophy. These findings suggest that CSF tau indices in AD may reflect tau-related neurodegeneration in the medial temporal lobe. However, it remains uncertain whether elevated CSF tau levels in the clinically heterogeneous subtypes of early-onset AD (EOAD; amnestic, posterior cortical atrophy [PCA], and logopenic progressive aphasia [LPA]) are attributable to similar underlying mechanisms...

This study investigated structural and functional magnetic resonance imaging abnormalities in hexanucleotide repeat expansion in chromosome 9 open reading frame 72 (C9orf72) motor neuron disease (MND) relative to disease severity-matched sporadic MND cases. We enrolled 19 C9orf72 and 67 disease severity-matched sporadic MND patients, and 22 controls. Sporadic cases were grouped in patients with: no cognitive/behavioral deficits (sporadic-motor); same patterns of cognitive/behavioral impairment as C9orf72 cases (sporadic-cognitive); shorter disease duration versus other sporadic groups (sporadic-early)...

OBJECTIVE: To identify the shared neuroimaging signature of gait slowing and cognitive impairment. METHODS: We assessed a cohort of older adults (n = 175, mean age 73 years, 57% female, 65% white) with repeated measures of gait speed over 14 years, MRI for gray matter volume (GMV) at year 10 or 11, and adjudicated cognitive status at year 14. Gait slowing was calculated by bayesian slopes corrected for intercepts, with higher values indicating faster decline. GMV was normalized to intracranial volume, with lower values indicating greater atrophy for 10 regions of interest (hippocampus, anterior and posterior cingulate, primary and supplementary motor cortices, posterior parietal lobe, middle frontal lobe, caudate, putamen, pallidum)...

BACKGROUND: In Parkinson's disease (PD), the relation between cortical brain atrophy on MRI and clinical progression is not straightforward. Determination of changes in structural covariance networks - patterns of covariance in grey matter density - has shown to be a valuable technique to detect subtle grey matter variations. We evaluated how structural network integrity in PD is related to clinical data. METHODS: 3 Tesla MRI was performed in 159 PD patients. We used nine standardized structural covariance networks identified in 370 healthy subjects as a template in the analysis of the PD data...

There is general agreement that perisylvian language cortex plays a major role in lexical and semantic processing; but the contribution of additional, more widespread, brain areas in the processing of different semantic word categories remains controversial. We investigated word processing in two groups of patients whose neurodegenerative diseases preferentially affect specific parts of the brain, to determine whether their performance would vary as a function of semantic categories proposed to recruit those brain regions...

OBJECTIVE: Patients with Lewy body disease develop a variety of psychotic and misperception symptoms, including visual hallucinations and delusions, as well as 'minor hallucinations', that is, a sense of presence, passage hallucinations and visual illusions. Although these symptoms have been suggested to have common underlying mechanisms, the commonalities and differences among them have not been systematically investigated at the neural level. METHODS: Sixty-seven patients with Parkinson's disease underwent neuropsychological and behavioural assessments, volumetric MRI and 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET)...

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BACKGROUND: Nowadays, there are many techniques to compensate bone atrophies of the posterior maxilla in order to obtain an implant-supported rehabilitation. OBJECTIVE: This case series describes the Ebanist technique: a sinus lift procedure to be used in case of extremely resorbed bone crests (≤3 mm) allowing simultaneous implant placement. METHODS: With a dedicated cylindrical trephine bur, it is possible to harvest a cylinder of bone from a fresh mineralized frozen homologous bone block graft and to simultaneously create a trapdoor on the recipient site...

BACKGROUND/AIMS: Alzheimer's disease (AD) shows a characteristic pattern of brain atrophy, with predominant involvement of posterior limbic structures, and relative preservation of rostral limbic and primary cortical regions. We aimed to investigate the diagnostic utility of two gray matter volume ratios based on this pattern, and to develop a fully automated method to calculate them from unprocessed MRI files. PATIENTS AND METHODS: Cross-sectional study of 118 subjects from the ADNI database, including normal controls and patients with mild cognitive impairment (MCI) and AD...

Higher body mass index (BMI) at midlife is associated with greater decreases in cognitive function at older age as well as increased Alzheimer's disease (AD) risk, compared to those with normal BMI. Here, we tested whether BMI at midlife was associated with cortical thinning in brain regions known to be affected in early AD. We examined a large sample (n = 404) of midlife individuals (44-49 years) from the PATH population-based study. Individuals were scanned with magnetic resonance imaging (1.5T) on up to three occasions over eight years...

The purpose of this investigation is to evaluate 2 different methods for reducing cortical wall thickness in sinus floor augmentation surgery. A manual bone scraper was compared in terms of efficacy, speed, and safety to an ultrasonic insert for osteoplasty, in a randomized controlled clinical trial with a split-mouth design. Twenty-five patients with severe posterior maxillary atrophy were treated with bilateral sinus floor elevation with lateral approach. Antrostomies were randomly performed by eroding the cortical wall with a manual bone scraper (test site) or with an ultrasonic insert (control site) until the membrane was visible under a thin layer of bone, before outlining the window with a piezoelectric device...

A 63-year-old woman presented to her ophthalmologist complaining of reading difficulties for two years. Ophthalmological examination revealed a homonymous hemianopsia. Brain magnetic resonance imaging (MRI) scan was interpreted as normal, but positron emission tomography (PET) showed areas of posterior brain hypometabolism. This case highlights the high diagnostic suspicion that ophthalmologists should have regarding posterior cortical atrophy (including the visual variant of Alzheimer disease) in patients complaining of reading difficulties in the setting of a normal ophthalmic examination...

Alien hand syndrome (AHS) is a neurological illness characterized by limb movements which are carried out without being aware of it. Many patients describe these movements as aggressive and some perceive a strong feeling of estrangement and go so far as to deny ownership. The sense of body ownership is the perception that parts of one's body pertain to oneself, despite it is moving or not and if movement is intentional or unintentional. These anomalous self-experiences may arise in patients with focal brain lesions and provide unique opportunities to disclose the neural components underlying self-body perception...

BACKGROUND: A three-dimensionally favourable mandibular bone crest is desirable to be able to successfully implant placement to meet the aesthetic and functional criteria in the implant-prosthetic rehabilitation. Several surgical procedures have been advocated for bone augmentation of the atrophic mandible, and the sandwich osteotomy is one of these techniques. The aim of the present case report was to assess the suitability of segmental mandibular sandwich osteotomy combined with a tunnel technique of soft tissue...