Postoperative vision loss (POVL) is an uncommon complication associated with nonocular surgeries like cardiac surgery and spine surgery done in the prone position. It results from ischemia to the visual pathway, particularly the optic nerve and retina, which receive their blood supply from the ophthalmic artery. The posterior portion of the optic nerve is more susceptible due to less vascular supply. Causes of POVL include ischemic optic neuropathy, central retinal artery occlusion, cortical blindness, and posterior reversible encephalopathy syndrome. Risk factors for POVL after cardiac and spine surgery include low hematocrit, vascular disease, long bypass or surgery time, blood transfusions, and direct eye compression during prone positioning. Prevention strategies focus on maintaining adequate hematocrit,

1. POSTOPERATIVE
VISION LOSS (POVL)
PRESENTED BY :
DR.ANKITA MADAN

2.  Partial or complete vision loss of vision occuring after
general anaesthesia for nonocular surgery.
 Uncommon complication
 Associated more with cardiac surgery or procedures on
the spine done in prone position.

3. PATHOPHYSIOLOGY
 Ischemia to visual pathway particulary the optic
nerve and the retina.
 Major source of blood supply of retina and optic
nerve is the Opthalmic artery branch of internal
carotid artery.
 Branches : Central retinal artery and long and
short posterior arteries – blood supply of retina

5. Posterior portion of optic nerve more susceptible to poor perfusion in
presence of hypotension due to comparatively less vascular supply.

7. CAUSES OF POVL
 Ischemic optic neuropathy (ION)
 Central retinal artery occlusion (CRAO)
 Cortical blindness
 Posterior reversible encephalopathy syndrome
(PRES)

8. VISION LOSS AFTER SPINAL
SURGERY
 Anterior ischemic optic neuropathy
 Posterior ischemic optic neuropathy
 Retinal vascular occlusion

9. ISCHEMIC OPTIC NEUROPATHY(ION)
Irreversible painless loss of vision
Spontaneously without any warning signs
Usually seen after cardiac surgery , spine
surgery , head and neck surgery , orthopedic
joint procedures and surgery on nose or
sinuses.

10. Two types - anterior or posterior ION
AION –Most commonly after cardiac
surgery
PION –After spine surgery in prone
postion or radical neck dissection.

12. MECHANISM FOR ION
 Increased venous pressure in the globe and
interstitial edema during prone position
 Increase in intraocular pressure
 Compression of vessels supplying optic nerve
 Hypoxia of optic nerve

13. RETINAL ISCHAEMIA
 CENTRAL RETINAL ARTERY OCCLUSION
decreases blood supply to the entire retina
 BRANCH RETINAL ARTERY OCCLUSION
affects only a portion of the retina.
 Following ocular trauma , embolic phenomenon
following carotid surgery and vasospastic
episodes.
 In spine surgery , it is due improper patient
positioning and external compression of eye.

14. POVL AFTER CARDIAC
SURGERY
 Risk factors :
 Lower postoperative haematocrit
 Presence of clinically significant vascular diseae
 Long duration of CPB
 Red cell transfusions
 Use of other blood components

15. POVL AFTER HEAD AND NECKSURGERY
 ION after neck dissection
 CRAO after neck and nasal or sinus surgery
 Orbital hemorrhage from blunt trauma during the
procedure

16. PERIOPERATIVE VISUAL LOSSIN OTHERSURGERIES
 After robotic and laparoscopic surgeries especially
after laparoscopic nephrectomies and robotic
prostatectomies.
 During robotic prostatectomy, patient in steep
trendelenburg position for a prolonged time and co2
insufflation of the abdomen increases the CVP , the
intrathoracic pressure and the intraocular pressure.

17. OTHER CAUSES OF POVL
CORTICAL BLINDNESS
 Result of decreased perfusion to the occipital
cortex due to hypoperfusion and embolic
phenomenon.
 Normal light reflex and fundoscopic examination.
 Prevention by maintaining normal perfusion
pressure and hematocrit of about 30%.

18. POSTERIORREVERSIBLE ENCEPHALOPATHY
SYNDROME (PRES)
 SEIZURES
 HEADACHE
 VOMITING
 VISION DEFECTS
 DECREASED LEVEL OF CONSCIOUSNESS.

19. Reported after severe hypertension ,
chemotherapy , immune suppression ,
renal disease , vasculitis and eclampsia ,
lumbar spine fusion , hysterectomy and
video assisted thoracoscopic surgery .
Treatment is symptomatic.

20. ASA PRACTICE ADVISORY
 Inform patients undergoing spine surgery of long
duration and expected excessive blood lossabout
small and unpredictable risk of POVL.
 Systemic BP to be monitored in high risk patients.
Deliberate hypotension should be practiced on case
by case basis.
 Central venous pressure must be monitored in high
risk patients.

21. To maintain hematocrit of above 28%
Use of vasopressors on case by case basis.
During positioning , direct compression on eyes
must be avoided and head should be maitained
in neutral position at the level or higher than the
level of heart.

22. Staging of surgical procedure must be given
consideration in high risk patients.
Vision must be tested of high risk patients for
POVL immediately after they are awake and
ophthalmology opinion must be taken urgently if
there is any concern.
Optimization of Hb level , hemodynamic status
and oxygenation may be addressed

23. THANKS 