CASE REPORT

Visual loss and ophthalmoplegia due to optic nerve infarction and central retinal artery occlusion after spine surgery in the prone position

경상대학교병원 마취통증의학과 이수희 Perioperative visual loss (POVL) after spine surgery - Incidence : 0.03% - Cause : hypotension, embolism, hemorrhagic shock, direct trauma, long time compression of eyes, etc - In particular, patients with carotid or occlusion have a relatively higher risk of vision loss than no stenosis

World J Orthop 2014;5:100-106 Med J Malaysia 2009;64:323-324 Case presentation

M/74

• planned to receive lumbar surgery for radiating leg pain under general anesthesia • Past Medical Hx: - HTN (5 yrs ago), cerebrovascular infarction (3 yrs ago) • Preoperative examination : carotid ultrasonography - calcified plaque at both carotid bulb & Lt. carotid artery was totally occluded.

Case presentation

• The total time for anesthesia and surgery was 375 minutes. • During surgery, 2 units of packed RBCs were transfused • The patient’s blood pressure and heart rate were maintained stable. • There were no other events during the procedure.

Case presentation

• After recovery form general anesthesia, the patient could not open his left eye because of swelling and he moved to a general ward. Case presentation

• After 12 hours since that surgery had ended, his Lt. eyelid still looked edematous and showed ptosis and visual loss in the Lt. eye. • No remarkable left eye pain. • He was checked further ophthalmologic and neurologic examination. • On the ophthalmologic examination, there was no perception of light and limited extraocular movement in all direction of gaze in the left eye which suggested total ophthalmoplegia (Fig.1)

Nine positions of gaze demonstrating the Figure 1. limitation of extraocular muscles in the Lt. eye at initial visit. Case presentation • P/E • Visula Acuities : 0.8 OD /Light perception(-) OS • IOP : 16/15mmHg/AT

• Conjunctivae : Non specific, OU • Anterior Chamber : Normal/cell(-), OU • Cornea : Clear, OU • Pupil: OD) 2.5mm OS) 5.0mm, Light Reflex(-) • Lens : IOL in situ, OU

Figure 2.

Post. Seg : cherry red spot, pale Normal fundus, OD retina, OS Figure 3. Fluorescein

OD) normal circulatory filling OS) Arterial filling time delay (about 27 secs) (about 27 secs)

Fluorescein angiograms of the left eye at the initial visit. (A) At 10 seconds after injection, filling of the retina and choroidal vessel is not seen. (B) At 27 seconds after injection, filling of the retinal and choroidal vessel is still incomplete. Figure 4. Brain MRI (Contrast)

High signal intensity, Lt. optic nerve (DWI) Swelling of Lt. extraocular muscles (T2)

Figure 5. MRI Angiography

Rt. ICA

Lt. VA

ECA

VA CCA Ophthalmic artery

ECA

CCA

• Complete occlusion, Lt proximal to petrous ICA • Engorgement, Lt. ophthalmic artery • brain MRA and MRI - to exclude perioperative cerebral infarction. - multiple focal chronic infarction, but no acute lesion. - Lt. ophthalmic artery showed engorgement - Lt. extraocular muscles was swelling state - Lt. ICA and Rt. VA obstruction - His ophthalmic artery circulation did not arise from the ICA • The feeding of his ophthalmic arterial circulation was estimated to be supplied by various branches of the ECA. • To recover movement of left extraocular muscles, treated with 1g of methylprednisolone intravenous injection for three days, switched to oral prednisolone, and then tapered to 60mg for three days and 30mg for three more days.

• Twenty days after the treatment, the swelling of his eyelids improved and the motion of the left extraocular muscle was somewhat improved. 20 days after treatment

Eyelid : Lt. eye Ptosis was improved EOM : Gaze limitation of Lt. eye was improved

Disccusion

• The Causes of POVL are classified into four categories; • Ischemic optic neuropathy (ION), central retinal artery occlusion (CRAO), cortical blindness, and posterior reversible encephalopathy syndrome World J Orthop 2014;5:100-106

• Most common cause of POVL : ION

• Independent risk factors related to ION after spinal fusion operation • Male gender, obesity, extensive blood loss, prolonged anesthesia, administration of a lower percentage of colloid, and use of the Wilson frame Anesthesiology 2012;116:15-24

Central retinal artery occlusion (CRAO)

• Reduces blood supply to the retina • Indicated that such occlusion is associated with head position and external compression of the eye, which is accompanied by ptosis and opthalmoplegia

Normal ophthalmic arterial circulation Variation • In most cases, the ophthalmic artery supplies blood to the orbit, it is the first branch of the internal carotid artery.

• In some patients, the ophthalmic artery did not arise from the internal carotid artery but originated various branches of the external carotid artery.

• In certain patients with severe ICA stenosis or occlusion, ophthalmic arterial flow can be reversed from antegrade to retrograde; under these circumstances, the ophthalmic artery is supplied by various branches of the ECA, including the facial, maxillary, and superficial temporal arteries. Eye (Lond) 2006;20:1130-1140 Disccusion

• Our patient showed visual loss of Lt. eye with total ophthalmoplegia. This patient had a history of cerebral infarction and chronic left internal carotid occlusion.

• If the chronic internal carotid artery is occluded, collateral circulations for sustained blood supply is developed.

• These collateral circulations are supplied through the circle of Willis, through the leptomeningeal anastomosis of the brain surface, or from the skull to the skull, the most common being the external carotid artery and ostial artery of the ipsilateral side. Disccusion

• In this patient with left proximal ICA occlusion, which was located proximal to the petrous ICA before the branching of the ophthalmic artery normally originated from the ICA

-> thus, based on prior reports, retrograde collateral circulation into the ophthalmic artery via the left ECA was suspected.

Eye (Lond) 2006;20:1130-1140 Int Angiolo 1994;13:5-9

• prolonged operation resulted in the retention of this collateral pathway, which may have caused circulatory disturbances in the eye and its surrounding tissues.

• Direct compression of the facial, maxillary and superficial temporal arteries, which are located in the face, while the patient was in the prone position ->>Possible causes that have contributed to compromised retrograde circulation of the Lt. ECA feeding the ophthalmic artery • For high-risk patients with proximal ICA stenosis occlusion who must undergo spine surgery in the prone position

• Need to explain about possible of POVL • Intraoperative measure to reduce the possibility of POVL should be considered • Find the abnormal ptosis after awakening->should have evaluated the eye problem as soon as possible. • to make an effort to quickly identify whether or not patient's eyes abnormity at recovery time from anesthesia, especially in prone position surgery. • If necessary, we should get the advice of your ophthalmologist as soon as possible to encourage eyeball recovery. • Ophthalmoplegia can be recovered because muscle cell is more tolerable in ischemic condition. • However, visual loss due to optic nerve infarction and central retinal artery occlusion is usually irreversible like this patient.

Conclusion

• For high-risk patients with retrograde collateral circulation of the ECA feeding the ophthalmic artery due to proximal ICA occlusion who undergo spine surgery in the prone position • Using a head fixator to provide completely direct compression-free positioning of the face and eyes • Less steep head-down position, • Preventing intraoperative hypotension

• If necessary, we should get the advice of your ophthalmologist as soon as possible to encourage eyeball recovery 경청해주셔서 감사합니다.