Disease-specific structural changes in thalamus and dentatorubrothalamic tract in progressive supranuclear palsy

Abstract

IntroductionThe aim of this study is to identify disease-specific changes of the thalamus, basal ganglia, pons, and midbrain in patients with progressive supranuclear palsy (PSP), Parkinson’s disease (PD), and multiple system atrophy with predominant parkinsonism (MSA-P) using diffusion tensor imaging and volumetric analysis.MethodsMRI diffusion and volumetric data were acquired in a derivation of 30 controls and 8 patients with PSP and a validation cohort comprised of controls (n = 21) and patients with PSP (n = 27), PD (n = 10), and MSA-P (n = 11). Analysis was performed using regions of interest (ROI), tract-based spatial statistic (TBSS), and tractography and results compared between diagnostic groups.ResultsIn the derivation cohort, we observed increased mean diffusivity (MD) in the thalamus, superior cerebellar peduncle, and the midbrain in PSP compared to controls. Furthermore, volumetric analysis showed reduced thalamic volumes in PSP. In the validation cohort, the observations of increased MD were replicated by ROI-based analysis and in the thalamus by TBSS-based analysis. Such differences were not found for patients with PD in any of the cohorts. Tractography of the dentatorubrothalamic tract (DRTT) showed increased MD in PSP patients from both cohorts compared to controls and in the validation cohort in PSP compared to PD and MSA patients. Increased MD in the thalamus and along the DRTT correlated with disease stage and motor function in PSP.ConclusionPatients with PSP, but not PD or MSA-P, exhibit signs of structural abnormalities in the thalamus and in the DRTT. These changes are associated with disease stage and impaired motor function.

Specificity and sensitivity of magnetic resonance imaging findings in the diagnosis of progressive supranuclear palsy

“…Signal change was assessed in 14 studies . Measures of diffusion were assessed with diffusion weighted imaging/diffusion tensor imaging (DWI/DTI) MRI in 12 studies . Other measures were used to distinguish PSP in seven studies .…”

“…Locations at which abnormalities in diffusion were commonly assessed included the putamen, superior and middle cerebellar peduncles and thalamus . Again, none of these studies tested the diagnostic accuracy of diffusion abnormalities against the gold standard of a pathological diagnosis of PSP.…”

“…13,19,21,29,37,40,[58][59][60][61][62][63][64][65] Measures of diffusion were assessed with diffusion weighted imaging/diffusion tensor imaging (DWI/DTI) MRI in 12 studies. 33,38,45,46,48,[66][67][68][69][70][71][72] Other measures were used to distinguish PSP in seven studies. 48,[73][74][75][76][77][78][79] There were 13 studies which reported MRI findings with ≥95% sensitivity and specificity for PSP (see Table 1).…”

“…Locations at which abnormalities in diffusion were commonly assessed included the putamen, 38,45,46,68,71 superior and middle cerebellar peduncles 33,38,45,[67][68][69][70] and thalamus. 45,72 Again, none of these studies tested the diagnostic accuracy of diffusion abnormalities against the gold standard of a pathological diagnosis of PSP. Three studies identified parameters that had ≥95% sensitivity and specificity for distinguishing another disease from PSP.…”

Track density imaging in progressive supranuclear palsy: A pilot study

“…DTI is a valuable noninvasive imaging technique for the assessment of the WM structure of the brain. In patients with PSP-RS, relative to PD patients and healthy controls, a greater WM degeneration (lower FA and higher MD) have been observed in the superior cerebellar peduncles, cerebellum, corpus callosum, cingulum, superior longitudinal fasciculus, and white matter laminar of thalamus (Blain et al, 2006;Canu et al, 2011;Erbetta et al, 2009;Ito, Makino, Shirai, & Hattori, 2008;Knake et al, 2010;Piattella et al, 2015;Saini et al, 2012;Surova et al, 2015). In patients with PSP-RS, relative to PD patients and healthy controls, a greater WM degeneration (lower FA and higher MD) have been observed in the superior cerebellar peduncles, cerebellum, corpus callosum, cingulum, superior longitudinal fasciculus, and white matter laminar of thalamus (Blain et al, 2006;Canu et al, 2011;Erbetta et al, 2009;Ito, Makino, Shirai, & Hattori, 2008;Knake et al, 2010;Piattella et al, 2015;Saini et al, 2012;Surova et al, 2015).…”