Case Of Posterior Cortical Atrophy Research Articles

Neurofibrillary tangle distribution in posterior cortical atrophy and early‐onset Alzheimer disease

AbstractBackgroundEarly onset sporadic Alzheimer’s disease (AD) sometimes presents with non‐memory symptoms attributed to relatively greater neocortical than hippocampal tau neurofibrillary tangle (NFT) density. Posterior cortical atrophy (PCA) is a variant of AD presenting with visuospatial deficits and atrophy of the occipital cortex, yet the pathologic underpinning is poorly understood.MethodWe examined brains of 50 patients with early onset (age<65 y.), autopsy‐confirmed AD from the UCSD Alzheimer’s Disease Research Center, 12 of whom were clinically diagnosed with PCA. Immunohistochemistry for tau was performed in the hippocampus (HP), midfrontal cortex (MF), and occipital cortex (OC), and the density of NFTs was measured.ResultPCA and non‐PCA patients did not significantly differ in age (63.35±4.59 y. at death) or sex (40% female). The APOE ε4 allele was much less frequent in PCA (p = 0.002). While the PCA group was less impaired on the MMSE (p = 0.01), they performed comparably on the CDR sum‐of‐boxes. The OC NFT density did not differ between the groups; however, the OC/HP (p = 0.04) and OC/MF (p = 0.008) ratios demonstrate that PCA cases had relatively greater OC pathology than non‐PCA patients. Across the groups, age at symptom onset was inversely associated with OC NFT density (p = 0.01) and the OC/HP NFT ratio (p = 0.008), such that earlier onset was associated with greater OC NFT burden. Visuospatial performance, measured by the Block Design test, was associated with the OC NFT density (p = 0.006), as well as the OC/HP (p = 0.007) and OC/MF NFT ratios (p = 0.03), with the effects remaining significant when restricting to non‐PCA participants. In contrast, memory performance measured by the Logical Memory Immediate Recall measure was only associated with HP NFT density (p = 0.02).ConclusionDespite differences in the predominance of early visuospatial symptoms, PCA and non‐PCA patients did not differ in OC tangle density, with some of the highest densities in non‐PCA patients. However, the degree of visuospatial impairment was associated with the OC/HP NFT ratio across both groups. Results suggest that greater memory impairment in the non‐PCA patients associated with a higher HP tangle density may moderate the predominance of visuospatial impairment so that they do not receive a formal PCA diagnosis.

Exploring the contribution of visual imagery to scene construction – Evidence from Posterior Cortical Atrophy

Posterior Cortical Atrophy (PCA) is a rare neurodegenerative syndrome characterised by profound visuoperceptual processing disturbances, attributable to focal parieto-occipital cortical atrophy. Despite relative sparing of the medial temporal lobes, converging evidence reveals significant autobiographical memory impairments in this syndrome, underscoring the crucial role of visual imagery for episodic memory processes. The contribution of visual imagery to complex constructive endeavours, however, remains unclear. Here, we investigated the capacity for atemporal scene construction in 5 well-characterised cases of PCA and contrasted their performance with 10 typical amnestic Alzheimer's Disease (AD) and 10 healthy older Control participants. Behavioural data were analysed using case-Control statistics comparing each PCA patient's scene construction scores to the mean scores of AD and Control groups. In keeping with their clinical phenotype, PCA patients demonstrated significant visuoperceptual and episodic memory impairments on standard neuropsychological tasks. Scene construction performance was grossly impaired in PCA, at a level comparable to that observed in the AD group, manifesting in impoverished and spatially fragmented scenes. Structural neuroimaging confirmed prominent grey matter intensity decrease predominantly in posterior cortical regions in PCA, in the absence of frank hippocampal atrophy. Using an a priori motivated region-of-interest approach across all participants, scene construction performance was found to correlate with grey matter intensity in the left angular gyrus, right precuneus, and right hippocampus. This study is the first to reveal compromised scene construction capacity in PCA, extending our understanding of the cognitive profile of this rare syndrome and pointing towards the fundamental contribution of visual imagery to atemporal forms of imagination.

Prevalence of Mathematical and Visuospatial Learning Disabilities in Patients With Posterior Cortical Atrophy

Increased prevalence of language-based learning disabilities (LDs) has been previously reported in patients with primary progressive aphasia (PPA). This study hypothesized that patients with focal neurodegenerative syndromes outside the language network, such as posterior cortical atrophy (PCA), would have a higher rate of nonlanguage LDs, congruent with their mainly visuospatial presentation. To investigate the prevalence and type of LD (language and/or mathematical and visuospatial) in a large cohort of patients with PCA compared with patients with logopenic variant PPA (lvPPA) and amnestic Alzheimer disease (AD). This case-control study reviewed 279 medical records from a university-based clinic and research center for patients with neurodegenerative diseases for LD history, including patients with PCA (n = 95), patients with lvPPA (n = 84), and a matched cohort with amnestic AD (n = 100). No records were excluded. The study compared cognitive and neuroimaging features of patients with PCA with and without LDs. A review of the records of patients presenting from March 1, 1999, to August 31, 2014, revealed 95 PCA cases and 84 lvPPA cases. Then 100 patients with amnestic AD from this same period were chosen for comparison, matching against the groups for age, sex, and disease severity. Data analysis was performed from September 8, 2013, to November 6, 2017. Prevalence of total LD history and prevalence of language and mathematical or visuospatial LD history across all cohorts. A total of 179 atypical AD cases (95 with PCA and 84 with lvPPA) and 100 disease control cases (amnestic AD) were included in the study. The groups were not statistically different for mean (SD) age at first visit (PCA, 61.9 [7.0] years; lvPPA, 65.1 [8.7] years; amnestic AD, 64.0 [12.6] years; P = .08), mean (SD) age at first symptom (PCA, 57.5 [7.0] years; lvPPA, 61.1 [9.0] years; amnestic AD, 59.6 [13.7] years; P = .06), or sex (PCA, 66.3% female; lvPPA, 56.0% female; amnestic AD, 57.0% female; P = .30) but differed on non-right-hand preference (PCA, 18.3%; lvPPA, 20.2%; amnestic AD, 7.7%; P = .04), race/ethnicity (PCA, 88.3% white; lvPPA, 99.0% white; amnestic AD, 80.0% white; P < .001), and mean (SD) educational level (PCA, 15.7 [3.2] years; lvPPA, 16.2 [3.3] years; amnestic AD, 14.8 [3.5] years; P = .02). A total of 18 of the 95 patients with PCA (18.9%) reported a history of LD, which is greater than the 3 of 100 patients (3.0%) in the amnestic AD cohort (P < .001) and the 10.0% expected rate in the general population (P = .007). In the PCA cohort, 13 of 95 patients (13.7%) had a nonlanguage mathematical and/or visuospatial LD; this rate was greater than that in the amnestic AD (1 of 100 [1.0%]; P < .001) and lvPPA (2 of 84 [2.4%]; P = .006) cohorts and greater than the 6.0% expected general population rate of mathematical LD (P = .003). Compared with the patients with PCA without LDs, the group with LDs had greater preservation of global cognition and a more right-lateralized pattern of atrophy. Nonlanguage mathematical and visuospatial LDs were associated with focal, visuospatial predominant neurodegenerative clinical syndromes. This finding supports the hypothesis that neurodevelopmental differences in specific brain networks are associated with phenotypic manifestation of later-life neurodegenerative disease.

A case of posterior cortical atrophy with vertical neglect

ABSTRACTPosterior cortical atrophy (PCA) is a syndrome caused by a neurodegenerative disease that often presents with visuospatial deficits, and can be debilitating. PCA is often characterized by elements of Balint’s syndrome and dyslexia. The most common underlying pathology has been found to be Alzheimer’s disease. Signs of horizontal neglect are frequently associated with PCA, but the presence of vertical (or altitudinal) neglect has not yet been reported in a patient with PCA or other forms of neurodegenerative dementia. In this paper, we present a patient with PCA who on vertical line bisection and cancellation tests revealed upper altitudinal spatial neglect. Detection of this abnormality may have important implications for diagnosis, therapeutic interventions, and patient safety.

A Case of Posterior Cortical Atrophy with Complex Set of Symptoms and Rapid Course

Posterior Cortical Atrophy (PCA), also called Benson’s syndrome, is a neurodegenerative disease characterized by a progressive occipital and parietal dysfunction, including visuospatial and visuoperceptual disorders, apraxia, alexia, acalculia and language deficit, with relative sparing of memory. We describe a case of PCA with some typical characteristics, such as visual symptoms at the onset, neuroimaging and CSF findings, but unusual for a tumultuous course with a rapidly worsening dementia and for the association with infrequent signs, such as myoclonus, postural tremor and grasping reflex.

Childhood Learning Disabilities and Atypical Dementia: A Retrospective Chart Review.

ObjectiveTo further our understanding of the association between self-reported childhood learning disabilities (LDs) and atypical dementia phenotypes (Atypical Dementia), including logopenic primary progressive aphasia (L-PPA), Posterior Cortical Atrophy (PCA), and Dysexecutive-type Alzheimer’s Disease (AD).MethodsThis retrospective case series analysis of 678 comprehensive neuropsychological assessments compared rates of self-reported LD between dementia patients diagnosed with Typical AD and those diagnosed with Atypical Dementia. 105 cases with neuroimaging or CSF data available and at least one neurology follow-up were identified as having been diagnosed by the neuropsychologist with any form of neurodegenerative dementia. These cases were subject to a consensus diagnostic process among three dementia experts using validated clinical criteria for AD and PPA. LD was considered Probable if two or more statements consistent with prior LD were documented within the Social & Developmental History of the initial neuropsychological evaluation.Results85 subjects (Typical AD n=68, Atypical AD n=17) were included in the final analysis. In logistic regression models adjusted for age, gender, handedness, education and symptom duration, patients with Probable LD, compared to patients without Probable LD, were significantly more likely to be diagnosed with Atypical Dementia vs. Typical AD (OR 13.1, 95% CI 1.3-128.4). All three of the L-PPA cases reporting a childhood LD endorsed childhood difficulty with language. By contrast, both PCA cases reporting Probable childhood LD endorsed difficulty with attention and/or math.ConclusionsIn people who develop dementia, childhood LD may predispose to atypical phenotypes. Future studies are required to confirm whether atypical neurodevelopment predisposes to regional-specific neuropathology in AD and other dementias.

GRN-related Frontotemporal Lobar Degeneration TDP43 Type A presenting as a case of Posterior Cortical Atrophy (P5.013)

GRN-related Frontotemporal Lobar Degeneration TDP43 Type A presenting as a case of Posterior Cortical Atrophy (P5.013)

Posterior Cortical Atrophy: Review of the Recent Literature

Posterior cortical atrophy (PCA) is a group of neurodegenerative dementing disorders characterized by initial predominant visual complaints followed by progressive decline in cognitive functions. The visuospatial and visuoperceptual defects arise from the dysfunction of, respectively, the dorsal (occipito-parietal) and the ventral (occipito-temporal) streams. Clinical symptoms, results of neuropsychological examination, and findings of posterior cerebral atrophy and/or posterior hypoperfusion/hypometabolism contribute to the diagnosis. However, owing to the insidious onset of PCA and the non-specificity of initial symptoms, the diagnosis is often delayed. Specific etiologies include Alzheimer's disease, dementia with Lewy bodies, subcortical gliosis, corticobasal degeneration, and prion-associated diseases. Alzheimer's disease accounts for at least 80 % of PCA cases. Recent research has concentrated on better defining the clinical presentation of PCA, improving neuroimaging analysis, testing new neuroimaging techniques, and developing biological measurements. Selected recent papers on PCA are reviewed in this article.

Agraphia in posterior cortical atrophy

Introduction: The Posterior Cortical Atrophy (PCA) is a neurodegenerative syndrome that is characterized by progressive decline in visuospatial, visuoperceptual/INS;, literacy and praxis skills. We report two cases of PCA with severe writing disorders.

Posterior Cortical Atrophy: Advice for Diagnosis and Implications for Management

SUMMARY The clinical presentation of Alzheimer’s disease (AD) is heterogeneous, especially in individuals with an early age at onset, where the presenting symptoms may be language, behavior or visual impairment. Posterior cortical atrophy (PCA) refers to a syndrome where visual processing and other posterior functions are the initial symptoms. While the majority of PCA cases reflect the underlying AD, a proportion of cases are caused by dementia with Lewy bodies, corticobasal degeneration or prion disease. PCA is sometimes not recognized until late into the disease or misattributed to anxiety or malingering owing to its low frequency, the early age at onset and the relatively atypical symptoms. This article describes the PCA syndrome, emphasizing its clinical features and how it relates to early-onset AD variants. In order to aid identification of this syndrome, the neuroimaging and neuropsychological features, as well as biomarkers of the underlying pathology, are also described briefly. Finally, the implications for treatment, compensatory strategies and rehabilitation, as well as management of comorbidities, are discussed.

Picture Agnosia as a Characteristic of Posterior Cortical Atrophy

Background: Posterior cortical atrophy (PCA) is a degenerative disease characterized by progressive visual agnosia with posterior cerebral atrophy. We examine the role of the picture naming test and make a number of suggestions with regard to diagnosing PCA as atypical dementia. Methods: We investigated 3 cases of early-stage PCA with 7 control cases of Alzheimer disease (AD). The patients and controls underwent a naming test with real objects and colored photographs of familiar objects. We then compared rates of correct answers. Results: Patients with early-stage PCA showed significant inability to recognize photographs compared to real objects (F = 196.284, p = 0.0000) as measured by analysis of variants. This difficulty was also significant to AD controls (F = 58.717, p = 0.0000). Conclusion: Picture agnosia is a characteristic symptom of early-stage PCA, and the picture naming test is useful for the diagnosis of PCA as atypical dementia at an early stage.

The Evolution of Alexia in Two Cases of Posterior Cortical Atrophy

Posterior cortical atrophy (PCA) is an uncommon presentation of Alzheimer's disease (AD), characterised by prevalent anatomo-functional involvement of posterior cortical areas. Accordingly, the main clinical features at onset are disorders of high-order visual processing, such as alexia and impairments of visuo-spatial and visuo-constructional abilities. The clinical features in the early stages of disease are variable, and they have been suggested to stem from prevalent ventral or dorsal brain pathology, and/or asymmetric hemispheric involvement. With disease progression, these differences tend to blur with the increasing severity of neuropsychological dysfunction. We report two PCA patients showing different patterns of reading impairment (respectively, letter-by-letter reading and neglect dyslexia). A follow-up study suggested that the qualitative features of alexia remain distinctive with disease evolution. In addition, single photon emission tomography (SPECT) studies revealed different patterns of hypoperfusion, consistent with the alexia types. A careful reading assessment can provide important insights to the pattern of progression of the disease in patients with PCA up to the late stages of the pathology.

Depressive Symptome als Erstmanifestation einer posterioren kortikalen Atrophie

Posterior cortical atrophy (PCA) is a neurodegenerative disease which leads to a dementing syndrome that involves an irreversible impairment of higher visual and spatial functions. Memory and language functions generally tend to be preserved better than in other types of dementia including Alzheimer's disease. Here we report a case of PCA, which initially was diagnosed and treated for about a year as a major depressive episode. While most patients initially present with neurologic symptoms, in some PCA cases secondary manifestations, such as e. g. affective symptoms, might appear before the onset of overt cognitive dysfunction. In some cases, this might lead to a diagnostic delay of this neurodegenerative disease.

P3-173: Apolipoprotein E frequency in posterior cortical atrophy and typical Alzheimer’s disease

Typical Alzheimer's disease (AD) is characterized by early episodic memory loss, whereas Posterior Cortical Atrophy (PCA) is characterized by visual agnosias, with a relative sparing of episodic memory early in the disease course. The majority of cases of PCA share pathological features with those of typical AD. A well defined risk factor of typical AD is the presence of the apolipoprotein E (APOE) 4 allele. To compare the APOE 4 allele frequency in typical AD and PCA. We conducted a case control study in which the APOE status was determined on 22 patients who fulfilled clinical criteria for PCA, were longitudinally assessed in our Alzheimer's Disease Research Centre and had stored DNA. These patients were matched for age at onset and sex to 37 cases of typical AD diagnosed by the NINCDS–ADRDA criteria, and 38 controls. The APOE4 allele frequency was compared using a chi–square test. Furthermore, the PCA cases were stratified by age at onset > 60 to access for possible interaction. There was no difference in years of education, or disease severity based on the MMSE, between the cases with PCA and typical AD. The mean age at onset was 60 years in both groups. The APOE4 allele frequency was 29.5% for PCA, 47.0% for typical AD, and 7.9% for controls. There was no difference in APOE 4 allele frequency between the cases of PCA and typical AD (p=0.47), or between PCA and controls (p=0.12). However, there was a difference between typical AD cases and normal controls (p =0.004). There was no difference when the PCA cases were stratified by age at onset > 60. We did not find any evidence for a difference in the APOE 4 allele frequency between PCA and typical AD.

A case with cholinesterase inhibitor responsive asymmetric posterior cortical atrophy

A 55-year-old right-handed woman presented initially with mild amnestic and depressive episodes but slowly developed progressive neurobehavioral symptoms, indicative of posterior cortical atrophy in ensuing years. A more detailed neurobehavioral test suggested predominant right temporo-parietal dysfunction with executive functional deficits. SPECT and MRI findings revealed right unilateral temporo-parietal involvement. Cholinesterase inhibitor administration led to amelioration of symptoms. We suggest that cases of posterior cortical atrophy or visual variant of Alzheimer's disease may be responsive to cholinesterase inhibitor therapy; however, the observation in a single case should be confirmed on larger populations in a clinical trial design with placebo control.

Posterior Cortical Atrophy: Clinical Presentation and Cognitive Deficits Compared to Alzheimer’s Disease

Background: Posterior cortical atrophy (PCA) is an uncommon dementia syndrome with initial manifestations of visual dysfunction and preservation of memory and language until late in the disease. Since prognosis and management differ from typical Alzheimer’s disease (tAD), clinical tests to distinguish PCA from tAD are needed. Methods: Fifteen PCA cases and 15 tAD cases, defined by clinical and MRI criteria, were compared by present symptoms and scores on four cognitive tests. Results: Symptoms of visual disturbance and dyslexia were more commonly reported in PCA cases (p = 0.0001 and p = 0.006, respectively), and memory loss was more commonly reported in tAD (p = 0.006). Patients with PCA were less accurate on the Cortical Vision Screening Test (t = 6.0; p < 0.001) and in copying the Rey-Osterreith Complex Figure (t = 6.0; p < 0.001), in comparison to the tAD group. Memory, evaluated by the Rey Auditory Verbal Learning Test, was impaired in both groups; however, delayed recall was more impaired in the tAD group (t = 2.5; p = 0.03). Conclusion: Compared to patients with tAD, patients with PCA are more likely to present to their providers with symptoms of visual dysfunction. Performance on simple tests of visual perception and copying can be used to distinguish the two disorders even a few years after initial symptoms.

Clinical, genetic, and neuropathologic characteristics of posterior cortical atrophy.

To examine the clinical, genetic, and neuropathologic features of posterior cortical atrophy (PCA). Using a broad definition of PCA as a syndrome with the insidious onset of visual dysfunction in the absence of primary ophthalmologic causes, the authors identified and then reviewed the presenting signs and symptoms, ApoE genotypes, tau haplotypes, and neuropathologic findings when available of PCA cases from two dementia research centers collected over the past 14 years. The authors identified 40 PCA cases. Their mean age at symptom onset was 60.5 +/- 8.9 years. There were twice as many women as men in the series. The principal types of visual impairment were simultanagnosia (82%) and visual field defect (47.5%). Acalculia, alexia, and anomia were also common. Insight was preserved in almost all (95%) early in the disorder. Neither apoE epsilon4 nor tau haplotype frequencies were different from typical Alzheimer disease (AD). Nine patients had died and underwent postmortem examination. Seven autopsied cases had AD pathology but when compared to typical AD, the neurofibrillary tangle (NFT) densities were significantly higher in Brodmann areas 17 and 18 (p < 0.05) and significantly lower in the hippocampus (p < 0.05). Two cases had corticobasal degeneration with maximal involvement of tau positive glial pathology in the posterior parietal lobe and Brodmann areas 17 and 18. PCA is a distinctive dementia syndrome in which the most pronounced pathologic involvement is in the occipitoparietal regions independent of the specific underlying pathology. AD was the most common pathologic cause, but its regional distribution differed from typical AD.

Posterior Cortical Atrophy: A Review of the Literature

The past three decades have seen an accumulation of reports of neurodegenerative disease with disruption to visual processing. Disorders of both visuospatial processing and visual recognition have been described, though the former predominate. But the conundrum of posterior cortical atrophy (PCA) is that while the clinical presentation is relatively homogeneous, the nosological status remains something of a puzzle. Many cases coming to pathology have had Alzheimer’s Disease (AD) but in a different distribution from that seen in typical AD (tAD). Patients with non-specific subcortical gliosis and, more occasionally, Creutzfeldt Jacob disease, neither of which have an obvious affinity with PCA, have also been described. On the other hand, no case of PCA has been reported with the pathology of either corticobasal degeneration or dementia with Lewy Bodies, both of which do commonly present with prominent parietal symptomatology.

Cortical Sensory Loss in a Patient with Posterior Cortical Atrophy: A Case Report

Patients with posterior cortical atrophy (PCA) who present with initial symptoms of higher visual function deficits eventually develop alexia, aphasia, and components of Balint’s syndrome or Gerstmann’s syndrome. Recently, pathological findings were reported for these patients that are generally suggestive of Alzheimer’s disease even though Creutzfeldt-Jakob disease (CJD) was presumed as an alternative cause of some autopsy-diagnosed PCA cases. Here, we report a case with a four-year progression of cognitive and higher visual function deterioration, and with features not described in previously reported PCA cases (i.e., a distinct sensory complaint and early frontal lobe involvement). To summarize, this case belongs to perceptual-motor syndrome of asymmetric cortical degeneration and the underlying neuropathology is more suggestive of Alzheimer’s disease than of Creutzfeldt-Jakob disease.

Posterior cortical atrophy. Two case reports and a review of the literature

We present two cases of progressive early-onset dementia with apraxia and visuospatial disability as initial manifestations. In the later stages of the illness Gerstmann's and Balint's syndromes developed. Structural neuroimaging demonstrated parieto-occipital atrophy and functional imaging revealed bilateral hypometabolism and hypoperfusion in these areas. These cases fulfil the diagnostic criteria of posterior cortical atrophy (PCA). Frontal lobe involvement became evident as the disease progressed. Alzheimer's disease also typically features this anterior spread and possibly this is the underlying pathological substrate for this clinical syndrome, although definite pathology is lacking. In this report, we describe longitudinal evolution in these two cases of PCA.