Clinical and radiological analysis of right temporal variant of frontotemporal dementia: A case report

Background: The right temporal variant of semantic dementia (rSD) is an anatomic variant characterized by a radiological pattern of asymmetric anterior temporal atrophy, with predominance of the right lobe. It constitutes a syndrome with primary progressive aphasia with differential cognitive and behavioral symptoms, the key manifestations being prosopagnosia, topographic agnosia, and impairment of socio-emotional functioning. Case presentation: We describe the case of a 59-year-old man who developed a progressive cognitive decline in a six-year period. The first clinical manifestation was semantic anomia and difficulty recognizing objects; he later developed prosopagnosia, topographic agnosia, and progressive deterioration of episodic memory. These cognitive symptoms were accompanied by behavioral changes. Brain magnetic resonance imaging revealed asymmetric atrophy in the temporal poles, predominantly in the right hippocampal formations. Discussion: The exposed case illustrates the clinical presentation of the right temporal variant of semantic dementia and how it correlates with specific neuroimaging findings. This correlation highlights the role of the right temporal lobe for developing multimodal concepts. Neuropathological and genetic characterization have been proposed as novel diagnostic approaches that might help distinguish right temporal variant of semantic dementia from other variants. Conclusions: Although the right temporal variant of semantic dementia presents distinctive clinical manifestations, clinical diagnosis alone may be challenging due to overlapping features with other variants of frontotemporal dementia (FTD), highlighting the limitations faced in settings with little access to neuropathological and genetic evaluations and the need for more comprehensive characterization of clinical diagnostic criteria through longitudinal studies.