Pure downgaze palsy from isolated infarction of the left paramedian thalamic-mesencephalon junction.

A 65-years-old female was hospitalized 24 h after experiencing the sudden onset of subjective reduction in visual acuity and hypersomnia. On admission to the neurological ward, she presented isolated downgaze palsy. A Magnetic Resonance Imaging of the brain disclosed a discrete, ovalar hyperintensity involving the left paramedian thalamic-mesencephalon junction. The lesion was consistent with infarction. Isolated downgaze palsy has been described in thrombosis of Artery of Percheron leading to infarction of bilateral paramedian thalami along with structures from the mesencephalic-diencephalic junction such as the Medial Longitudinal Fasciculus (riMLF). While neurons from the riMLF controlling upward vertical saccades project to either ipsilateral and contralateral oculomotor nuclear complexes, those involved in regulating downgaze descend ipsilaterally in the brain stem. Isolated downgaze palsy has an extreme localizer value to the diencephalic-mesencephalon junction and can arise from a unilateral lesion.

Using Downgaze Palsy Progression Rate to Model Survival in Progressive Supranuclear Palsy-Richardson Syndrome.

BACKGROUND: Rapid development of downgaze palsy, the most specific symptom of progressive supranuclear palsy (PSP), has been associated with shorter survival in small studies. OBJECTIVE: We hypothesized that the progression rate of downgaze palsy and other disease features could predict survival if assessed soon after the onset of downgaze palsy in a large data set. METHODS: We used a longitudinal database of 414 patients with probable PSP-Richardson syndrome from 1994 to 2020. The data set comprised demographics and, for each visit, 28 PSP Rating Scale (PSPRS) items and PSP stage scores. We calculated the rate of progression of each PSPRS item as its item score when the downgaze item first reached 1 or more (on a 0-4 scale) divided by disease duration at that point. Multivariate Cox regression was applied to identify variables independently associated with survival. We also explored the progression pattern of total PSPRS and downgaze palsy scores with disease course. RESULTS: Independently associated with shorter survival were older onset age and faster progression of downgaze palsy, dysphagia for liquids, difficulty in returning to seat, and PSP stage. Patients with survival duration within 1 year of the median survival (6.58 years) showed approximately linear progression of the PSPRS score and downgaze palsy score during years 2 through 6 of the disease course. CONCLUSIONS: Older onset age and faster progression of downgaze palsy and several axial features are associated with shorter survival. The disease typically progresses in approximately linear fashion during years 2 through 6. These results may aid study design and patient counseling. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Severity of Downgaze Palsy in the Context of Disease Duration Could Estimate Survival Duration in Patients With Progressive Supranuclear Palsy.

It is an unmet need to estimate survival duration for patients with progressive supranuclear palsy (PSP). The objective of this study was to identify factors associated with the survival duration in patients with PSP. We followed up 23 patients with probable PSP-RS (Richardson syndrome) or PSP-P (parkinsonism) in our PSP center until death from 2011 to 2019. We prospectively and quantitatively rated their downgaze palsy whenever first noticed in our clinic. This was utilized along with the disease duration, motor function, medication use for parkinsonism, sex, age at onset of PSP, comorbid pulmonary and cardiovascular diseases, and the total survival duration from the onset of PSP to death for prediction analysis. A well-fitted linear regression model and a multivariant Cox model were applied to identify predicting factors for total survival duration. All patients had the specific hummingbird sign on brain MRI for PSP when downgaze palsy was documented. We found that the severity of downgaze palsy and the disease duration at the assessment were consistently correlated with the total survival duration in both models. The total survival duration could be further estimated by a formed regression equation. We conclude that severity and time to develop downgaze palsy could help to estimate the total survival duration in patients with probable PSP-RS and PSP-P, the major forms of PSP, which has significant clinical applications in clinical counseling and trial enrollment.