Retinal degeneration in progressive supranuclear palsy measured by optical coherence tomography and scanning laser polarimetry

Retinal Thinning as a Marker of Disease Severity in Progressive Supranuclear Palsy

OBJECTIVE

Progressive supranuclear palsy (PSP) involves a variety of visual symptoms that are thought to be partially caused by structural abnormalities of the retina. However, the relationship between retinal structural changes, disease severity, and intracranial alterations remains unknown. We investigated distinct retinal thinning patterns and their relationship with clinical severity and intracranial alterations in a PSP cohort.

METHODS

We enrolled 19 patients with PSP (38 eyes) and 20 age-matched healthy controls (40 eyes). All of the participants underwent peripapillary and macular optical coherence tomography. Brain 11C-2β-carbomethoxy-3β-(4-fluorophenyl) tropane (11C-CFT) and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography imaging were also performed in patients with PSP. We investigated the association between retinal thickness changes and clinical features, striatal dopamine transporter availability, and cerebral glucose metabolism.

RESULTS

The peripapillary retinal nerve fiber layer (pRNFL) and macula were significantly thinner in patients with PSP than in controls. The thickness of the superior sector of the pRNFL demonstrated a significant negative relationship with the Movement Disorder Society-Unified Parkinson's Disease Rating Scale part III and Hoehn and Yahr staging scale scores. A significant negative correlation was found between outer inferior macular thickness and disease duration. Outer temporal macular thickness was positively correlated with Montreal Cognitive Assessment scores. In PSP, lower outer temporal macular thickness was also positively correlated with decreased dopamine transporter binding in the caudate.

CONCLUSION

The pRNFL and macular thinning may be candidate markers for monitoring disease severity. Additionally, macular thinning may be an in vivo indicator of nigrostriatal dopaminergic cell degeneration in PSP patients.

The Correlation between Retinal and Choroidal Thickness with Age-Related White Matter Hyperintensities in Progressive Supranuclear Palsy

Progressive supranuclear palsy (PSP) is a rare neurodegenerative disease. Recently, several retinal layers in PSP compared to healthy controls. were found to be thinner. However, no studies evaluating the correlation between retinal layers and cerebral white matter changes, nor eventual choroidal changes in PSP, have been conducted so far. The goals of the present study were to explore potential differences in choroidal structure between PSP and healthy controls, and to describe the relationship between retinal layers' thickness and volume, using spectral-domain optical coherence tomography (SD-OCT) and age-related white matter change scores (ARWMC) using magnetic resonance imaging (MRI) of the brain. Choroidal structures of 26 PSP patients and 26 healthy controls using standard SD-OCT with an enhanced depth imaging (EDI) approach were analyzed; then, retinal the structures of 16 of these PSP patients using standard SD-OCT were examined; finally, the same patients underwent brain MRI, and their cerebral white matter changes were calculated. Non-statistically significant differences between PSP patients' and healthy controls' choroidal structure were found. On the contrary, PSP patients' inner retinal layers (INR), retinal pigmented epithelium (RPE) and all retinal layers' thicknesses in the macular region were found to be significantly correlated with ARWMC, independently from age and axial length (AL). PSP patients' neurological alterations go hand in hand with retinal ones, independently from age and axial length. Our results suggest a mutual relationship between cerebral and retinal structure pathological alterations. On the other hand, no significant differences in the choroidal evaluation compared to healthy controls have been found.

Retinal Structure Abnormalities in Parkinson's Disease and Atypical Parkinsonism

We investigated retinal structure changes in patients with Parkinson's disease (PD), multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and controls, and explored the value of this method in differential diagnosis. Spectral domain optical coherence tomography (SD-OCT) was used to measure peripapillary retinal nerve fiber layer (pRNFL) thickness, and macular thickness and volume. PSP patients showed higher temporal pRNFL thickness than PD and MSA patients. Peripapillary RNFL thickness could be used for discriminating PSP from MSA and PD. PD and MSA patients showed retinal thinning in the foveal center circle and nasal inner sectors compared to controls. Macular thickness and volume could be used for discriminating MSA from PD. There were negative correlations between disease duration and OCT parameters in PD, MSA, and PSP, independent of age, sex ratio, and the side of the eye. PD and atypical parkinsonism correlate with specific patterns of retina alterations. OCT could be a biomarker for differential diagnosis and progression evaluation of parkinsonian syndrome.

Retinal nerve fiber layer in frontotemporal lobar degeneration and amyotrophic lateral sclerosis

Purpose

Tauopathy and transactive response DNA binding protein 43 (TDP-43) proteinopathy are associated with neurodegenerative diseases. These proteinopathies are difficult to detect in vivo. This study examined if spectral-domain optical coherence tomography (SD-OCT) can differentiate in vivo the difference in peripapillary retinal nerve fibre layer (pRNFL) thickness and macular retinal thickness between participants with presumed tauopathy (progressive supranuclear palsy) and those with presumed TDP-43 proteinopathy (amyotrophic lateral sclerosis and semantic variant primary progressive aphasia).

Study design

Prospective, multi-centre, observational study.

Materials and methods

pRNFL and macular SD-OCT images were acquired in both eyes of each participant using Heidelberg Spectralis SD-OCT. Global and pRNFL thickness in 6 sectors were analyzed, as well as macular thickness in a central 1 mm diameter zone and 4 surrounding sectors. Linear mixed model methods adjusting for baseline differences between groups were used to compare the two groups with respect to pRNFL and macular thickness.

Results

A significant difference was found in mean pRNFL thickness between groups, with the TDP-43 group (n = 28 eyes) having a significantly thinner pRNFL in the temporal sector than the tauopathy group (n = 9 eyes; mean difference = 15.46 μm, SE = 6.98, p = 0.046), which was not significant after adjusting for multiple comparisons. No other significant differences were found between groups for pRNFL or macular thickness.

Conclusion

The finding that the temporal pRNFL in the TDP-43 group was on average 15.46 μm thinner could potentially have clinical significance. Future work with larger sample sizes, longitudinal studies, and at the level of retinal sublayers will help to determine the utility of SD-OCT to differentiate between these two proteinopathies.

Retinal thinning in progressive supranuclear palsy: differences with healthy controls and correlation with clinical variables

Background

Available evidence reports conflicting data on retinal thickness in progressive supranuclear palsy (PSP). In studies including healthy controls, PSP showed either the thinning of the retinal nerve fiber layer, macular ganglion cell, inner nuclear, or outer retina layer.

Objectives

The goals of the present study were to describe retinal layer thickness in a large cohort of PSP compared to healthy controls and in PSP phenotypes using spectral-domain optical coherence tomography (SD-OCT). The additional objective was to verify the relationship between retinal layers thickness and clinical variables in PSP.

Methods

Using a cross-sectional design, we examined retinal structure in 27 PSP patients and 27 controls using standard SD-OCT. Motor and cognitive impairment in PSP was rated with the PSP rating scale and the Montreal Cognitive Assessment battery (MoCA), respectively. Eyes with poor image quality or confounding diseases were excluded. SD-OCT measures of PSP and controls were compared with parametric testing, and correlations between retinal layer thicknesses and disease severity were evaluated.

Results

PSP showed significant thinning of the inner retinal layer (IRL), ganglion cell layer (GCL), inner plexiform layer (IPL), and the outer plexiform layer (OPL) compared to healthy controls. PSP phenotypes showed similar retinal layer thicknesses. Retinal layer thickness correlated with MoCA visuospatial subscore (p < 0.001).

Conclusions

We demonstrated PSP patients disclosed thinner IRL, GCL, IPL, and OPL compared to healthy controls. Furthermore, we found a significant correlation between visuospatial abilities and retinal layers suggesting the existence of a mutual relationship between posterior cognitive function and retinal structure.

Peripapillary retinal nerve fiber layer thinning in patients with progressive supranuclear palsy

Objectives

To investigate peripapillary retinal nerve fiber layer (pRNFL) changes in patients with progressive supranuclear palsy (PSP).

Methods

We included 21 PSP patients (36 eyes) who underwent peripapillary optical coherence tomography (OCT) scans at 2.5 ± 1.3 years of disease, without ophthalmologic co-morbidities. We compared pRNFL thicknesses in PSP eyes with age-matched 22 controls (22 eyes) using generalized estimating equation model adjusting for intra-subject inter-eye correlations, age and sex. We also analyzed the correlation between the pRNFL thickness and clinical severity using Spearman’s correlation. In twelve PSP patients with 3 T brain MRI volumetric scan within 1 year of OCT exam, we investigated the correlation between the pRNFL thickness and brain atrophy using Pearson’s correlation.

Results

PSP patients had global pRNFL thinning compared to controls (beta = − 6.436, p = 0.025). Global pRNFL thickness correlated with Hoehn & Yahr stages (r = − 0.487, p = 0.025), and nasal pRNFL thinning showed a trend of correlation (uncorrected p < 0.05). Exploratory correlation analysis between global pRNFL thickness and nonmotor items in the PSP rating scale showed a trend toward association with sleep disturbances (uncorrected p = 0.008) and urinary incontinence (uncorrected p = 0.031), although not significant after Bonferroni correction (all 28 items). The patients had significant atrophy in the posterior cingulate cortex, third ventricle, pallidum, and midbrain with reduced midbrain-to-pons ratio, but no correlation was found between pRNFL thickness and brain volumes.

Conclusion

The pRNFL seems to be affected in PSP, which is more severe with advanced disease stages. Retinal investigation in a larger longitudinal cohort would help elucidate the pathophysiological role of retinal thinning in PSP.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-021-10936-5.

An Eye on Movement Disorders

Eye disorders spanning a range of ocular tissue are common in patients with movement disorders. Highlighting these ocular manifestations will benefit patients and may even aid in diagnosis. In this educational review we outline the anatomy and function of the ocular tissues with a focus on the tissues most affected in movement disorders. We review the movement disorders associated with ocular pathology and where possible explore the underlying cellular basis thought to be driving the pathology and provide a brief overview of ophthalmic investigations available to the neurologist. This review does not cover intracranial primary visual pathways, higher visual function, or the ocular motor system.

Retina thickness in atypical parkinsonism: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

To investigate the retina thickness assessed using optical coherence tomography in atypical parkinsonism in comparison with health controls (HC) and patients with Parkinson's disease (PD).

METHODS

PubMed and EMBASE were searched for potentially eligible studies that reported retina thickness in atypical parkinsonism [including progressive supranuclear palsy (PSP), multiple system atrophy (MSA) and corticobasal degeneration] in comparison with that of HC and PD patients from their dates of inception to Jan 24, 2021. Mean difference (μm) of the thickness of peripapillary retinal nerve fiber layer (pRNFL) and central macular thickness (CMT) were pooled with random effects model.

RESULTS

We included ten studies eligible for inclusion criteria. Average pRNFL thickness and average CMT were thinner in PSP [pooled mean difference (μm) of - 4.71, 95% CI (- 7.15, - 2.27); - 15.12, 95% CI (- 16.93, - 13.30)] and in MSA [- 5.37, 95% CI (- 6.59, - 4.15); - 5.93, 95% CI (- 11.00, - 0.87)] compared with HC, and were thinner in PSP [- 5.81, 95% CI (- 8.92, - 2.69); - 10.63, 95% CI (- 20.29, - 0.98)] and in MSA [- 0.35 μm, 95% CI (- 5.72, 5.01); - 7.42 μm [95% CI (- 12.46, - 2.38)] compared with PD. The pRNFL thickness was thinning in superior, inferior and nasal quadrants, and CMT was thinning in outer sectors in MSA compared with HC.

CONCLUSIONS

The retina thickness was significantly thinner in PSP and MSA than those in HC and PD. The specific patterns of retina thinning in MSA could be clinical importance for differentiation among atypical parkinsonism.

The circadian system in Parkinson's disease, multiple system atrophy, and progressive supranuclear palsy

Circadian organization of physiology and behavior is an important biologic process that allows organisms to anticipate and prepare for predictable changes in the environment. Circadian disruptions are associated with a wide range of health issues. In patients with neurodegenerative diseases, alterations of circadian rhythms are among the most common and debilitating symptoms. Although a growing awareness of these symptoms has occurred during the last decade, their underlying neuropathophysiologic circuitry remains poorly understood and, consequently, no effective therapeutic strategies are available to alleviate these health issues. Recent studies have examined the neuropathologic status of the different neural components of the circuitry governing the generation of circadian rhythms in neurodegenerative diseases. In this review, we will dissect the potential contribution of dysfunctions in the different nodes of this circuitry to circadian alterations in patients with parkinsonism-linked neurodegenerative diseases (namely, Parkinson's disease, multiple system atrophy, and progressive supranuclear palsy). A deeper understanding of these mechanisms will provide not only a better understanding of disease neuropathophysiology but also holds promise for the development of more effective and mechanisms-based therapies.

Optical coherence tomography of patients with Parkinson's disease and progressive supranuclear palsy

OBJECTIVES

To determine if Parkinson's disease (PD) and progressive supranuclear palsy (PSP) differed on retinal measurements using optical coherence tomography (OCT).

PATIENTS AND METHODS

In a prospective, controlled, cross-sectional cohort study, we recruited patients with PD or PSP for more than three years, as well as control subjects. We measured peripapillary retinal nerve fiber layer (RNFL) thickness and macular volume using spectral-domain OCT. The association between these OCT measures and the disease characteristics of duration and disability were examined using a linear mixed effect model.

RESULTS

We analyzed eyes from n = 12 PD patients, n = 11 PSP patients, and n = 12 control subjects. RNFL thickness was reduced in eyes from patients with PSP, but there were no differences in macular volume between groups. RNFL thickness and macular volume were not significantly different between eyes from patients with PD and controls. Worse disability was associated with reduced macular volumes.

CONCLUSION

PSP but not PD is associated with thinning of the peripapillary RNFL when symptoms have been present for more than three years.

The role of Optical Coherence Tomography in Parkinsonism: A critical review

Optical coherence tomography (OCT) has been evaluated as a tool to assess retinal changes in various neurodegenerative disorders. Parkinson's disease (PD), is a neurodegenerative disorder wherein dopaminergic deficiency results in some of the symptoms. As retina also has high concentration of dopamine, it would be of interest for both the clinician as well as the basic scientist to know if there is a correlation between the clinical features and the retinal changes. The objective of this review is to critically evaluate the literature and study the utility of OCT as a tool to evaluate retinal changes in PD.

Treatment of Visual Disorders in Parkinson Disease

PURPOSE OF REVIEW

This article discusses visual disorders in both Parkinson disease (PD) and other Parkinsonian disorders. It is organized largely by the anatomical site of pathology and emphasizes practical treatments. Targeted treatment options include medications, surgery, occupational, and physical therapies as well as optical aids.

RECENT FINDINGS

The causes of visual complaints in Parkinson disease and other similar disorders are being more clearly identified. A new medication approved specifically to treat hallucinations in PD now is available. There is increased understanding of the important role that an ophthalmologist can play in the care of these patients. Finally, research and therapeutic development are unmet needs in accessing and treating visual complaints in PD and Parkinsonian disorders. A better understanding of Parkinson-related visual complaints and of available treatment options is important to optimize patient safety and quality of life. Vision impairment leads to difficulties in many common activities including reading, ambulating, and driving. Falls and injuries, made more likely because of impaired vision, result in an early loss of independence. Awareness of the problem, patient education, ophthalmologic care, selected therapeutics, physical therapy, and occupational therapy are crucial to maximizing quality of life in these patients.