Clinical features and imaging biomarkers of posterior cortical atrophy

Objective To summarize the clinical and imaging features of patients with posterior cortical atrophy (PCA). Methods and Results Five patients with PCA admitted in West China Hospital, Sichuan University from April to June 2021 were included. All of them showed spatial perception disorder, simultaneous agnosia, miscalculation, agraphia, structural apraxia, environmental agnosia. Apraxia of dressing and agnosia of left and right were found in 3 cases. One case had facial agnosia, visual ataxia and object perception disorder. Cerebrospinal fluid (CSF) biomarker determination: amyloid β⁃protein 42 (Aβ42) decreased in 3 cases, the ratio of Aβ42/amyloid β⁃protein 40 (Aβ40) decreased significantly in 2 cases, the content of total tau protein (t ⁃ tau) increased in all 5 cases, phosphorylated tau 181 protein (p ⁃ tau181) increased in 3 cases. Neuropsychological tests showed that: 1) Five patients all had different degrees of cognitive dysfunction and impairment of activities of daily living, as well as impairment of visuospatial ability, visual memory and attention. 2) Three cases had anxiety and depression, language and executive function were impaired in 3 cases, and verbal memory was impaired in 2 cases. Head MRI examination all indicated different degrees of parieto ⁃ occipital ⁃temporal cortical atrophy. Hypometabolism in posterior regions involving parietal and temporal cortex was observed in one case with 18F⁃FDG PET. Three cases completed the visual field examination, including 5 cases of binocular vision loss, one case of complete visual field defect, 2 cases of partial visual field defect. Except one case lost to follow⁃up, other 4 cases were followed up for 20-22 months. Two cases of cognitive function, visuospatical ability decline, of which one case could not take care of themselves most of the life. Cognitive function and visuospatial ability improved in one case. There was no significant change in cognitive function and visuospatial ability in one case. Conclusions PCA should be considered in patients with relatively early⁃onset of agnosia, visual field defect and visuospatial impairment. Comprehensive neuropsychological tests related to visual function, brain MRI, 18F⁃FDG PET and CSF biomarkers would be helpful for accurate diagnosis.