Richardson Syndrome Variant of Progressive Supranuclear Palsy: A Case Report

Progressive supranuclear palsy (PSP) is a chronic neurodegenerative disease, an atypical parkinsonism with four-repeat tau neuropathology. PSP-Richardson syndrome (PSP-RS) is the most prevalent clinical variant of PSP, originally described as the prototypical form of the disease. It is defined by vertical supranuclear gaze palsy (most prominently affecting downward gaze), early postural instability with frequent falls, and a subcortical-frontal pattern of cognitive impairment. The diagnosis of PSP is mainly based on clinical data and is only definitively confirmed at autopsy. Neuroimaging plays an important role in early diagnosis. Our report describes the case of a 72-year-old female patient who had experienced subtle symptoms for approximately two years prior to presentation. Initially, she exhibited slow and monotonous speech, mild decline in fine motor skills, intermittent episodes of impaired concentration, and mild forgetfulness. At presentation to the outpatient clinic, she reported falls, imbalance, bradykinesia, cognitive decline, limitation of vertical gaze, and diplopia. The patient's systemic examination was normal. Neurological examination showed vertical gaze palsy, postural instability, bradykinesia, and a shuffling gait. Bilateral upper extremity associative movements were slow. The Mini-Mental State Examination Score was 19. Axial T2-weighted magnetic resonance imaging (MRI) showed midbrain atrophy, as well as the hummingbird sign and morning glory sign, characteristic of PSP. Axial T1 MRI showed cerebral atrophy and dilatation of the bilateral lateral and third ventricles. Initially, levodopa/benserazide was started at a dose of 500 mg/day and increased up to 1,000 mg/day. Amantadine at a dose of 200 mg/day and levodopa/carbidopa sustained release at a dose of 200/50 mg/day were added to the treatment regimen, but no effective clinical response was observed. Balance and walking exercises were provided by the physical therapy and rehabilitation department. This case highlights the subtle prodromal features and progressive course of PSP, emphasizing the importance of early recognition. It also contributes to the literature by illustrating the clinical progression and therapeutic challenges in managing PSP, underscoring the value of a multidisciplinary approach to optimize patient outcomes.