PSP-like syndrome after aortic surgery in adults (Mokri syndrome)

Abstract

BackgroundA rare progressive supranuclear palsy–like syndrome seemingly triggered by aortic surgery was first described in 2004. This largest case series to date describes the features of this syndrome.MethodsWe searched the Mayo Clinic electronic medical records using the advanced cohort explorer search engine for patients evaluated for neurologic symptoms after cardiac-aortic surgery in the past 30 years. Data were extracted to Microsoft Excel from the identified patients and included clinical and neuroimaging features and outcomes.ResultsTwenty-five patients met the inclusion criteria. All surgeries were performed under thoracic aortic bypass and deep hypothermia. Surgery included aortic aneurysm, aortic valve repair, and/or aortic dissection repair. Surgical records were unavailable, although surgery was documented in the Mayo record as uncomplicated in 60% of cases. In the remaining cases, no particular intraoperative or postoperative complications were documented at a high frequency. A typical triad was documented: supranuclear gaze palsy (SNGP; 100%), gait imbalance (80%), and dysarthria (96%). Part or all of the triad was observed before hospital discharge and stabilized over the course of days-weeks. A second phase of symptom worsening plus new symptoms developed up to a year later; this decline continued for up to several years before stabilization. Delayed epileptic seizures occurred in 32% of patients. Brain MRI revealed only nonspecific findings.ConclusionThis syndrome following adult thoracic aortic bypass surgery with deep hypothermia remains unexplained. It follows a biphasic course and is characterized by the triad of SNGP, unsteady gait, and a predominantly ataxic dysarthria.

The Significance of Vascular Pathogenesis in the Examination of Corticobasal Syndrome

“…It is a rare disorder appearing after ascending aorta surgery. The typical symptoms include supranuclear gaze palsy, gait imbalance and dysarthria ( Mokri et al, 2004 ; Tisel et al, 2020 ). AD differs from other tauopathies in the presence of β-amyloid peptide, but not only the neurodegenerative basis of this disease but also the correlation between AD and CVD attracts interest of the researchers in this field ( Liesz, 2019 ).…”

Movement Disorders Associated With Radiotherapy and Surgical Procedures

“…43 Occurring after aortic surgery, this relatively uncommon syndrome is characterized by a triad of supranuclear gaze palsy, dysarthria and gaze disturbance (Table 3). [43][44][45][46][47][48][49][50][51][52][53][54][55][56] Although it is suggested that there is a higher prevalence of this syndrome in men, this is likely due to the higher prevalence of thoracic aortic aneurysms and abdominal aortic dissections in men.…”

“…43 One possible explanation postulated for Mokri syndrome is the use of profound hypothermia (12.5°C to 30°C) during aortic surgeries in comparison to other cardiac surgeries. 44 Although hypothermia is considered a neuroprotective strategy, patients may develop ischemia if rewarming is carried out rapidly. Furthermore, this ischemia may further impact patients who develop hyperglycemia during hypothermia.…”

“…All these factors can lead to vasoconstriction and impaired microcirculation. 44 Another proposed mechanism is multiple emboli in the posterior circulation; however, structural imaging has been found to be normal in most cases. 47 While AV-1451 tau PET was nor-mal in one case, fluorodeoxyglucose-positron emission tomography (FDG-PET) demonstrated the 'pimple sign, ' which is consistent with PSP; however, the DAT scan was normal.…”

“…47 While AV-1451 tau PET was nor-mal in one case, fluorodeoxyglucose-positron emission tomography (FDG-PET) demonstrated the 'pimple sign, ' which is consistent with PSP; however, the DAT scan was normal. 44 Mokri syndrome is unresponsive to levodopa and has a poor prognosis.…”