Chromatic Pupillometry to Assess the Melanopsin-Light Pathway in Progressive Supranuclear Palsy (PMPSP)

November 3, 2017 updated by: Shirley Wray, Massachusetts General Hospital

Functional Assessment of the Melanopsin-Containing Retinal Ganglion Cells in Progressive Supranuclear Palsy Using Chromatic Pupillometry

The specific aim of this study is to investigate rod, cone and melanopsin driven pupillary light response in individuals with progressive supranuclear palsy (PSP), age-matched healthy controls and individuals with other neurodegenerative diseases using chromatic pupillometry, with special interest in assessing melanopsin-driven post-illumination pupil response (PIPR) as an identifier for PSP.

The study addresses the following hypotheses:

  1. Chromatic pupil responses, including rod/cone-driven rapid phase constriction and melanopsin-driven PIPR, are reduced in subjects with PSP compared to age-matched normal healthy control subjects,
  2. Pupil parameters of the melanopsin-driven PIPR are abnormal in PSP subjects without supranuclear palsy, which is indicative of a subclinical physiological deficit of the OPN in the early stages of PSP.

If these hypotheses are upheld, chromatic pupillometry to measure the PIPR promises to be a reliable in vivo, non-invasive, convenient and inexpensive technique to detect asymptomatic pupillomotor impairment in advance of diagnostic oculomotor signs and deterioration of cognitive function.

Study Overview

Detailed Description

In 1963, Richardson, Steele and Olszewski published a landmark clinical report on 8 cases of supranuclear ophthalmoplegia, pseudobulbar palsy, nuchal dystonia and dementia and established the syndrome of heterogeneous system degeneration as a clinicopathological entity now known as PSP. The disease has a characteristic onset in the sixth decade (range 45 to 75 years) with some combination of impaired balance, abrupt falls, visual disturbances, slurred speech, dysphasia and vague changes in personality.

Slowing of voluntary vertical saccades, either down, up or both are a diagnostic marker of PSP and later impairment of voluntary horizontal saccades are characteristic in more than half of the cases. However, a proportion of PSP patients do not demonstrate these eye signs for a year or more after the onset of the disease.

This pilot study will use chromatic pupillometry to determine whether such a novel methodology may be used as an objective in vivo identifier of PSP. The rationale for the study is based in part on:

  1. Clinicopathological correlation between the key clinical signs of a supranuclear gaze palsy with pathological verification that the degenerative process affects the pretectum and rostral midbrain,
  2. The melanopsin-signaling pathway from ipRGCs (intrinsically photosensitive retinal ganglion cells) in the eye projects to the OPN (olivary pretectal nucleus) in the midbrain,
  3. Chromatic pupillometry is a non-invasive technique suitable for elderly subjects with or without dementia.

Study Type

Observational

Enrollment (Anticipated)

56

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

    • Massachusetts
      • Boston, Massachusetts, United States, 02114
        • Recruiting
        • Massachusetts General Hospital
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

53 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

Subjects diagnosed with PSP and age-matched control subjects

Description

Inclusion Criteria:

  1. Individuals that meet the clinical criteria for PSP. Core features include:

    • Recurrent falls and unsteady gait
    • Axial and nuchal rigidity
    • Pseudobulbar palsy
    • Bilateral lid retraction
    • Supranuclear vertical gaze palsy
    • Atrophy of the midbrain tegmentum (the hummingbird sign on brain MRI,
  2. Individuals that fit the criteria for the second PSP phenotype (which resembles PD) that has asymmetric findings, tremors and poor responses to treatment with Levodopa,
  3. Individuals that meet the clinical criteria for PD with:

    • Progressive bradykinesia
    • Postural instability and frequent falls
    • Festinating gait with loss of associated movements
    • Cogwheel rigidity and mask-like face
    • Rest tremor,
  4. Individuals who carry a diagnosis of Alzheimer' disease who present with progressive impairment of memory and cognitive domains such as language and visuospatial perception.

Diagnoses will be confirmed by the review of health/medical records of patients recruited from the Frontotemporal Disorders Unit clinic. In the case of participants recruited from research studies, diagnoses will be confirmed by the review of the research diagnoses indicated on the individuals' research records.

Exclusion Criteria:

  1. Individuals who are frail or in questionable health,
  2. Individuals with cataracts or with posterior pole ocular pathology such as age-related macular degeneration and optic neuropathies, including open angle high intraocular pressure glaucoma,
  3. Individuals with photophobia (i.e., painful light sensitivity) when exposed to bright light, including those with ophthalmological conditions such as keratitis (herpes simplex), uveitis or Achromatopsia,
  4. Individuals with advanced dementia with inability to sit erect, hold the eyes open, incontinence,
  5. Individuals with epilepsy,
  6. Individuals diagnosed with major depression or other severe psychiatric disorders

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: Cohort
  • Time Perspectives: Prospective

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
Neurodegenerative Diseases
Individuals with neurodegenerative diseases
Use of pupillometry to assess melanopsin-light pathway in patients with neurodegenerative diseases

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Maximal Pupil Constriction
Time Frame: 2 years
The smallest pupil size following light stimulation. This parameter primarily represents rapid phase extrinsic ipRGC activity driven by rods and cones through synaptic input.
2 years
Post-illumination pupil response (PIPR)
Time Frame: 2 years
Measured pupil diameter over a period of 20 seconds, from 10 to 30 seconds after the offset of light stimulation.
2 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Shirley H Wray, MD, PhD, Massachusetts General Hospital

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

November 1, 2017

Primary Completion (Anticipated)

October 1, 2019

Study Completion (Anticipated)

October 1, 2019

Study Registration Dates

First Submitted

September 19, 2017

First Submitted That Met QC Criteria

October 31, 2017

First Posted (Actual)

November 6, 2017

Study Record Updates

Last Update Posted (Actual)

November 7, 2017

Last Update Submitted That Met QC Criteria

November 3, 2017

Last Verified

November 1, 2017

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

No

IPD Plan Description

Coded data will be shared with co-investigators

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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