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Perioperative visual loss

Most Common Causes of Perioperative Visual Loss

 Corneal abrasionRetinal ischemiaIschemic optic neuropathy
SymptomsPainful foreign body sensation, visual acuity may be intact
Painless loss of vision
Unilateral
Periorbital edema
Proptosis
Chemosis
Extraocular muscle injury
Ecchymosis
Painless loss of vision
Bilateral
EtiologyCorneal epithelial defect in anterior segment
Central retinal artery occlusion
Branch retinal artery occlusion (retinal microemboli or vasospasm)
Elevated intraocular pressure
Unknown, perhaps related to optic nerve ischemia, vascular insufficiency, although often no other clinically significant end-organ damage
Risk factors
Unprotected, exposed eyes
Intraoperative contact lens use
Prone positioning
Spine surgery
Cardiac surgery, bypass
External orbital pressure
Prone positioning
Spine surgery (PION)
Cardiac surgery (AION)
Prolonged surgery
?Deliberate hypotension
?Hypoxia
?Hemodilution
?Vasoconstrictors
?Anemia
?Elevated venous pressure (e.g., Trendelenburg)
DiagnosisSlit lamp examination withfluorescein
Afferent pupillary defect
Pale swollen optic disc
Cherry red retina
Ground glass retina
Afferent pupillary defect or nonreactive pupil (CNII)
AION: optic disc edema
PION: normal optic disc
Abnormal visual-evoked potentials
TreatmentAntibiotic drops
IV acetazolamide
5% CO2 + O2inhalation
Ocular massage
?Ophthalmic artery fibrinolysis
Attempt to optimize oxygenation and orbital perfusion pressure, although no definitive treatment
Prognosis
Good prognosis
Expect recovery
Poor prognosis
Permanent visual loss
Poor prognosis
Permanent visual loss
Prevention
Tape eyes securely
No benefit to lubricant
Remove contact lenses
Avoid external orbital pressure
Frequently examine eyes during prone cases
Stage long spine procedures
Nadir hematocrit does not differ in patients with ION and those unaffected in noncardiac surgery
Massive fluid replacement may be a risk factor for ION (no clear evidence)

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