Parkinson diseases (PD) is the second most common degenerative disease of the central nervous system. The development of early diagnostic biomarkers may help identify at-risk individuals and allow precocious interventions at the onset of disease and more precise monitoring of therapies that may slow disease progression.

Proof of concept studies indicated significant differences in pupil light response between PD patients and healthy controls. The feasibility of using pupillometry for assesment of PD will be examined.

Inclusion Criteria:

• General inclusion criteria

  1. Age 30-75 years old
  2. Signed written informed consent
  3. Gender: Both (Male and Female)
  4. Pupillary reflex to light.
  5. Clear ocular media

Patients' Inclusion Criteria:

Patients with clinical presentations of the neurodegenerative forms of parkinsonism (bradykinesia, extrapyramidal rigidity, tremor, postural instability and gait disturbance) including: idiopathic Parkinson disease (PD), Lewy body disease (LBD), progressive supranuclear palsy (PSP), multiple system atrophy (MSA), corticobasal degeneration (CBD) and secondary parkinsonisms.

Control group- inclusion criteria

1. Normal eye examination

2. Best-corrected visual acuity (BCVA) of 20/20

3. Normal color vision test (Farnsworth/Lanthon D-15 Test)

4. No present ocular disease

5. No past ocular disease or surgery within last 6 months

6. No use of any topical or systemic medications that could adversely influence efferent pupil movements

7. Normal 24-2 Humphrey visual field and

   • Short duration (≤10 minutes)
   • Minimal fixation losses, False positive errors and False negative errors (less than 30% for each one of reliability indices)

Exclusion Criteria:

1. Diagnosis of dementia.
2. Cognitive decline that may impair obtaining informed consent.
3. Tremor or dyskinesia that could interfere with ophthalmic evaluation
4. History of past (last 3 months) or present ocular disease or ocular surgery
5. Use of any topical or systemic medications that could adversely influence pupillary reflex
6. Psychiatric illness, active psychosis.
7. Previous neurosurgical interventions, including stereotactic neurosurgical procedures.
8. Past or current strokes or brain injury and other brain disorders (except PD/parkinsonism for patient group)
9. Anti-dopaminergic drugs.
10. Intolerance to gonioscopy, slit lamp examination, Goldmann applanation tomometry or other schedule study procedure.
11. Visual media opacity including cloudy corneas.
12. Any condition preventing accurate measurement or examination of the pupil.

One hundred Parkinson patients or patients with parkinsonism and 100 age-matched controls