Out of Sight
aka Ophthalmology Befuddler 028
We’re coming to the end of an absolutely eyeful Ophthalmology August here at LITFL. Over the month we’ve considered many different causes of loss of vision. Today’s Q&A’s will bring together all the different ways the ‘lights can go out’ — don’t forget keep your ultrasound machine handy…
Are you ready for the ‘out of sight / loss of vision challenge’?
Questions
Q1. What are the important nontraumatic causes of transient (<24h) monocular vision loss?
Answer and interpretation
Common causes of non-traumatic transient visual loss include:
- amaurosis fugax (usually minutes) — usually embolic or thrombotic; can occur secondary to hypoperfusion states, hyperviscosity or vasospasm.
- migraine (can be without headache)
- one eye closed!
Uncommon causes include:
- papilloedema (may be associated with visual loss lasting seconds)
- other causes of ischemic optic neuropathy, e.g. giant cell arteritis
- impending central retinal vein occlusion (CRVO)
- glaucoma
- posterior reversible encephalopathy syndrome (PRES)
- large vessel occlusion or dissection, e.g. ocular ischemic syndrome (carotid occlusive disease), vertebrobasilar insufficiency, and carotid or vertebral artery dissection
- functional visual loss, e.g. hysteria, malingering
Q2. What are the important nontraumatic causes of acute persistent monocular vision loss?
Answer and interpretation
Painless acute persistent loss of vision:
- central retinal artery occlusion (CRAO)
- central retinal vein occlusion (CRVO)
- retinal detachment or hemorrhage
- vitreous hemorrhage
- optic or retrobulbar neuritis
- internal carotid artery occlusion
Painful acute loss of vision:
- acute glaucoma
- endophalmitis
- uveitis
- keratoconus (vision can deteriroate rapidly and is associated with photophobia)
Q3. What are the important nontraumatic causes of acute binocular loss of vision?
Answer and interpretation
Transient
- migraine
- VBI (transient)
Prolonged
- CVA
- poisons/ toxic optic neuropathy (e.g. methanol, quinine, ethambutol, ergot alkaloids, salicylates)
- posterior reversible encephalopathy (PRES)
- optic or retrobulbar neuritis
- hysteria
- malingering
Q4. What are the important post-traumatic causes of loss of vision?
Answer and interpretation
From ‘front to back‘:
- lid injury
- corneal irregularity or laceration
- hyphema
- ruptured globe
- traumatic cataract
- lens dislocation
- commotio retinae
- retinal detachment
- retinial or vitreous hemorrhage
- intra-ocular foreign body
- traumatic optic neuropathy or optic nerve avulsion
- CNS injury
Q5. What important cause(s) of visual loss should be suspected if the following features are present?
Based on Jeff Mann’s clinical clues
central loss of vision
…show answer
optic nerve disorders, macular degeneration, diabetes mellitus
visual loss that respects the horizontal midline (‘altitudinal’)
…show answer
‘prechiasmal’ lesions — optic neuritis, optic neuropathies, glaucoma, branch retinal vein occlusion
visual loss that respects the vertical midline
…show answer
‘postchiasmal’ lesions — ischaemia, hemorrhage, tumors, inflammation, trauma
Loss of vision in one eye
…show answer
Eye or optic nerve pathology
Loss of vision in both eyes
…show answer
Visual pathway pathology, bilateral optic neuritis, bilateral ischemic optic neuropathy (cerebral arteritis), toxic optic neuropathy
Sudden onset of painless loss of vision
…show answer
Central retinal artery occlusion, acute ischemic optic neuropathy, vitreous hemorrhage
Patient does not complain of visual loss, but bumps into objects when ambulating
…show answer
Temporal vision field defect with macular sparing
Cloudy vision with floaters
…show answer
Retinal detachment, vitreous hemorrhage
Flashing lights experience
…show answer
Retinal detachment
Curtain-like veil obscuring vision
…show answer
Retinal detachment
Curtain coming across vision like a shutter from above or below
…show answer
Central retinal artery occlusion
Vague central vision obscurations — “fluffy ball” or “puff of smoke”, or complaint of a sensation of “looking through ground glass”, or a claim that vision would be normal if he could only “see around it”
…show answer
Optic neuritis
Transient visual obscurations during any movement or change of position such as bending, straining or getting up suddenly
…show answer
Papilledema
Previous transient visual obscurations lasting seconds
…show answer
Papilledema, retinal vein occlusion
Previous transient visual obscurations lasting minutes
…show answer
Amaurosis fugax
Photopsias (positive visual phenomena — spontaneous flashing squares, flashes of light, showers of sparks) precipitated by eye movements
…show answer
Optic neuritis
Visual blurring made worse by hot weather or hot shower
…show answer
Optic neuritis
Visual distortions such as metamorphosia (straight lines are bent) or micropsia (objects appear smaller)
…show answer
Retinal detachment, macular degeneration, sub-retinal hemorrhage or edema
Eye pain at rest
…show answer
Iritis, acute angle-closure glaucoma, compressive intraorbital pathology
Eye pain with eye movements
…show answer
Corneal lesions, iritis, optic neuritis, intraorbital infiltrative or compressive pathology
Diffuse or localised headache, pain on combing the hair, temporal area pain especially when laying the head down on a pillow, jaw claudication, prolonged unexplained fever, malaise, weight loss, proximal myalgias, age > 50
…show answer
Temporal arteritis and secondary acute ischemic neuropathy or retinal artery occlusion
Visual loss with diplopia
…show answer
Intra-orbital, orbital apex pathology
Visual loss with focal neurological symptoms or signs
…show answer
CNS lesion (e.g. stroke) affecting the visual pathways
Recent trauma
…show answer
- Remember Q4?
- Traumatic cause of loss of vision from ‘front to back’ include:
- lid injury, corneal irregularity or laceration, hyphema, ruptured globe, traumatic cataractm lens dislocation, commotio retinae, retinal detachment, retinal or vitreous hemorrhage, intra-ocular foreign body, traumatic optic neuropathy or optic nerve avulsion, CNS injury
HIV
…show answer
HIV retinitis, CMV retinitis, toxoplasmosis or histoplasmosis retinitis
…and finally
Dr Sam Tapsell summarizes the visual fields and vision loss
References
- Ehlers JP, Shah CP, Fenton GL, Hoskins EN. The Wills Eye Manual: Office and Emergency Room Diagnosis and Treatment of Eye Disease Lippincott Williams & Wilkins
- NSW Statewide Opthalmology Service. Eye Emergency Manual — An illustrated Guide. [Free PDF]
OPHTHALMOLOGY BEFUDDLER
Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a 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 three amazing children.
On Twitter, he is @precordialthump.
| INTENSIVE | RAGE | Resuscitology | SMACC