Pupils And Prostitutes

aka Ophthalmology Befuddler 017

On examining a patient’s eyes you note that the pupils are small, irregular, non-reactive to light and constrict when focused on a near object.

Questions

Q1. What is the likely diagnosis?
Answer and interpretation

Q2. What does this abnormality have in common with prostitutes?
Answer and interpretation

They both accommodate, but don’t react“, and both are associated with neurosyphilis.

You may have remembered the answer from an old Funtabulously Frivolous Friday Five question. It may be politically incorrect, but it sure helps remember the key facts about Argyll Robertson pupils.


Q3. What are the features of this abnormality?
Answer and interpretation
  • small, irregular, unequal pupils
  • near-light dissociation (brisk accommodation but no light reaction)

These features are demonstrated in this classic video:


Q4. What other causes of near-light dissociation are there?
Answer and interpretation

Near-light dissociation is generally a feature of midbrain lesions that somehow affect iridodilator nerve fibers. the causes include:

  • syphilis (true Argyll Robertson pupils — the precise anatomic lesion is poorly understood)
  • diabetes mellitus
  • alcoholic midbrain degeneration (rare)
  • other midbrain lesions, e.g. sarcoidosis, encephalitis, Parinaud syndrome
  • abnormal regeneration of the oculomotor (CN3) nerve
  • tonic phase of the Holmes-Adie pupil

Sometimes the non-syphilitic pupillary abnormalities are called pseudo-Argyll Robertson pupils.


Q5. How did this ocular abnormality get its name?
Answer and interpretation

Douglas Moray Cooper Lamb Argyll Robertson (1837-1909) was a Scottish ophthalmologist. He was the first to describe his eponymous pupillary abnormality among patients with tabes dorsalis.

Argyll Robertson was also the first to demonstrate the cholinergic ocular effects of an extract from the Calabar bean, the drug physostigmine. Later he was consulted by a patient who lived in ‘Old Calabar‘ (in modern day Nigeria) about the ‘Calabar swellings’ that affected her eyes. He extracted filiarial Loa loa worms from these lumps and was thus one of the first to describe ocular loasis.


Q6. What is Parinaud syndrome?
Answer and interpretation

Parinaud syndrome is also called dorsal midbrain syndrome, it is another cause of near-light dissociation.

Parinaud syndrome is characterised by the following features:

  • vertical gaze palsy
  • near-light dissociation

It results from direct or compressive injury to the dorsal midbrain, affecting regions such as the superior colliculus adjacent to the oculomotor (CN3) and Edinger-Westphal nuclei (see diagram here).

Causes of Parinaud syndrome include:

  • neoplasms, especially pinealomas
  • multiple sclerosis
  • brainstem CVA
  • other causes including: toxoplasmosis of the brainstem, hydrocephalus, trauma, midbrain hemorrhage, and arteriovenous malformations

Named after Henry Parinaud, a French ophthalmologist (1844-1905)

Pearce JM. Parinaud’s syndrome. J. Neurol. Neurosurg. Psychiatr. 2005;76 (1): 99. [PMC1739319]


References

Ophthalmology Befuddler 700

CLINICAL CASES

Ophthalmology Befuddler

Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also the Innovation Lead for the Australian Centre for Health Innovation at Alfred Health and Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of two amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

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