Perioperative posterior ischemic optic neuropathy: review of the literature

Posterior ischemic optic neuropathy following continuous renal replacement therapy: a case report

BACKGROUND

Posterior ischemic optic neuropathy (PION) is a rare cause of acute vision loss in intensive care unit patients. PION following continuous renal replacement therapy (CRRT) hemodialysis has not ever been reported. Here, we report a case of bilateral nonarteritic PION following the initiation of CRRT.

CASE PRESENTATION

A 52-year-old man with hypertension and stage 4 chronic kidney disease was admitted due to metabolic acidosis, hyperkalemia, and acute exacerbation of CKD. CRRT caused transient hypotension upon initiation but corrected the metabolic acidosis and hyperkalemia six hours after initiation. Therefore, CRRT was stopped. However, several hours after the cessation of CRRT, the patient experienced sudden, painless vision loss in both eyes. Assessment of his visual acuity revealed the inability to perceive light in both eyes. There were no symptoms or signs of giant cell arteritis. An ophthalmological examination revealed no abnormalities. Magnetic resonance imaging of the brain revealed no compressive lesions or acute stroke, but magnetic resonance angiography revealed stenosis of both the bilateral carotid artery and the right middle cerebral artery. Administration of a high dose of corticosteroids did not reverse his vision loss. Thus, nonarteritic PION following CRRT was diagnosed.

CONCLUSIONS

PION should be considered if a patient with multiple vascular risk factors complains of sudden painless vision loss without signs of optic disk edema after the initiation of CRRT. Preventing blood pressure drops during the initiation of CRRT in patients with multiple vascular risk factors may prevent PION.

Postoperative Glaucoma Decompensation Following Spine Surgery: The Importance of Proper Patient Positioning

Transforaminal lumbar interbody fusion (TLIF) is a widely utilized surgical procedure for the treatment of degenerative lumbar spinal conditions, including lumbar disc herniations, spinal stenosis, and spondylolisthesis. One such rare and underreported complication is vision loss following spinal surgery. Postoperative vision loss (POVL) is an extremely uncommon complication, occurring in approximately 0.002% to 0.2% of all non-ocular surgeries, including spinal procedures. We presented a 70-year-old male with complaints of left-sided cruralgia, lumbar radicular pain (sciatica-type L5), and right-sided weakness who underwent L4-S1 TLIF and who reported complete vision loss in his left eye, accompanied by persistent tearing from the affected eye whenever he attempted to focus his vision. The patient's vision in the left eye, which had been stable and functional prior to surgery, was permanently affected by the intraoperative complication. At the three-month follow-up, ophthalmological assessments confirmed that the optic nerve damage was irreversible, and the patient's vision in the left eye remained completely blurred. Postoperative vision loss (POVL) is a rare but devastating complication associated with various types of surgeries, including spinal procedures like transforaminal lumbar interbody fusion (TLIF). The present case of a 70-year-old patient developing permanent vision loss in his left eye due to glaucoma decompensation after TLIF underscores the importance of proper intraoperative positioning, especially in patients with pre-existing ocular conditions.

Incipient and Established Anterior Ischemic Optic Neuropathy Following Liposuction Surgery

Ischemic optic neuropathy is a severe condition causing perioperative visual loss that may occur after a wide range of non-ocular surgeries, including liposuction. Several cases of non-arteritic anterior ischemic optic neuropathy (NAION) as a complication of liposuction have been published. Most have features in common such as anemia and altitudinal visual field defects. We report a case of incipient NAION in one eye and established NAION in the fellow eye after abdominoplasty, mastopexy, and large-volume liposuction, which complicated with anemia, but visual function recovered.

Delayed-Onset Idiopathic Intracranial Hypertension After Liposuction: A Case Report and Review

ABSTRACT

Although systemic complications following liposuction are rare, visual impairment has been reported in a few cases and may occur for a variety of reasons. Here we present the case of a 31-year-old woman who underwent 360° liposuction and subsequently developed headaches and delayed partial visual disturbance 10 days after the procedure. She had symptoms suggestive of idiopathic intracranial hypertension, which was confirmed by lumbar puncture. A literature search revealed other case reports of visual changes or headaches following high-volume liposuction. Our case provides further evidence of a rare association between liposuction and idiopathic intracranial hypertension, emphasizing the need for thorough preoperative evaluations and the consideration of possible risks.

Perioperative Blindness in Spine Surgery: A Scoping Literature Review

Perioperative vision loss (POVL) is a devastating surgical complication that impacts both the recovery from surgery and quality of life, most commonly occurring after spine surgery. With rates of spine surgery dramatically increasing, the prevalence of POVL will increase proportionately. This scoping review aims to aggregate the literature pertinent to POVL in spine surgery and consolidate recommendations and preventative measures to reduce the risk of POVL. There are several causes of POVL, and the main contribution following spine surgery is ischemic optic neuropathy (ION). Vision loss often manifests immediately following surgery and is irreversible and severe. Diffusion weighted imaging has recently surfaced as a diagnostic tool to identify ION. There are no effective treatments; therefore, risk stratification for counseling and prevention are vital. Patients undergoing prone surgery of long duration and/or with significant expected blood loss are at greatest risk. Future research is necessary to develop effective treatments.

External Compressive Ischemic Orbitopathy: A Rising Clinical Entity

PURPOSE

Saturday night retinopathy, the term coined by Jayam et al . in 1974, is a rare condition in which external compression of the orbit during a drug and alcohol stupor causes a unilateral orbitopathy with ophthalmoplegia and ischemic retinopathy. This condition has been increasingly reported in the last decade, correlating with an increasing burden of substance use. This condition mirrors a similar entity typically reported in patients following spinal surgery, where a headrest supporting the patient's face compresses the orbit. The current authors combine these 2 entities, entitled external compressive ischemic orbitopathy, and present a comprehensive literature review describing this entity.

METHODS

A systematic review was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. All related publications of vision loss in the setting of orbital compression were reviewed. Data collected included patient demographics, precipitating circumstances of vision loss, presenting ocular symptoms, outcomes, and ancillary imaging.

RESULTS

In total 31 articles were selected for inclusion, yielding 46 patients. A total of 10 patients suffered orbitopathy in the setting of a drug stupor, and 36 following prone-positioned surgery. However, 79% of patients presented with visual acuity of light perception or worse. Also, 86% of patients presented with ophthalmoplegia, 92% with proptosis and orbital edema, and 86% with varying degrees of retinal ischemia. When compared with iatrogenic cases, self-induced stuporous cases demonstrated worse presenting visual acuity, ophthalmoplegia, retinal and choroidal filling, and worse final outcomes.

CONCLUSION

External compressive ischemic orbitopathy is a severe vision-threatening condition that has been increasingly reported in the last decade.

Optic neuropathy associated with acute pancreatitis: A case report

The present article describes a case of a 24-year-old patient who suffered from acute pancreatitis. The patient simultaneously developed visual acuity loss and changes in the visual field. When examined, the finding was physiological, including the fundoscopy. Neither fluorescein angiography or optical coherence tomography demonstrated any retinal abnormalities; electroretinography was physiological as well. The visual evoked potentials (VEP) showed abnormalities in amplitudes. Patient's visual field was reduced to 40˚. The follow-up examination 13 months after the first symptoms proved a progression of changes in the visual field and prolonged latency of P100 peak in VEP. The retinal nerve fibre layer stayed unchanged, but the vessel density on the optic nerve head decreased. Magnetic resonance brain imaging showed non-specific subcortical and paraventricular focuses in the white matter of both hemispheres. There were no other abnormalities detected by magnetic resonance imaging. Neurological examination was normal. In conclusion, the present study verified this decrease of visual functions as a lesion in the visual pathway using VEP, which was also confirmed by magnetic resonance brain imaging.

Perioperative Care of the Patient with Eye Pathologies Undergoing Nonocular Surgery

The authors reviewed perioperative ocular complications and implications of ocular diseases during nonocular surgeries. Exposure keratopathy, the most common perioperative eye injury, is preventable. Ischemic optic neuropathy, the leading cause of perioperative blindness, has well-defined risk factors. The incidence of ischemic optic neuropathy after spine fusion, but not cardiac surgery, has been decreasing. Central retinal artery occlusion during spine fusion surgery can be prevented by protecting eyes from compression. Perioperative acute angle closure glaucoma is a vision-threatening emergency that can be successfully treated by rapid reduction of elevated intraocular pressure. Differential diagnoses of visual dysfunction in the perioperative period and treatments are detailed. Although glaucoma is increasingly prevalent and often questions arise concerning perioperative anesthetic management, evidence-based recommendations to guide safe anesthesia care in patients with glaucoma are currently lacking. Patients with low vision present challenges to the anesthesia provider that are becoming more common as the population ages.

Recovery of vision after treatment of hemodialysis related bilateral optic nerve ischemia

Purpose

We present the case of a patient who lost light perception in both eyes after hemodialysis and subsequently recovered vision after treatment with erythropoietin and intravenous steroids.

Observations

Our patient reported loss of light perception in both eyes (NLP) 2 hours after hemodialysis. Examination confirmed NLP vision, chronic retinal vascular changes, and no acute changes in optic nerve appearance. A presumptive diagnosis of posterior optic neuropathy was made. The patient was treated with erythropoietin and intravenous steroids according to the protocol of Nikkah. Over a period of 14 hours, he recovered vision to his baseline.

Conclusions and Importance

Bilateral loss of light perception is a rare complication of hemodialysis. The presumed mechanism is posterior ischemic optic neuropathy. Prompt treatment with erythropoietin and intravenous steroids should be considered in similar situations that result in Posterior ischemic optic neuropathy (PION) related to procedure-based hypotension.

Posterior Ischemic Optic Neuropathy after Cervical Spine Surgery

Purpose: To describe a patient with posterior ischemic optic neuropathy (PION) after cervical spine surgery who recovered after treatment.Case summary: A 51-year-old woman presented with eye pain and decreased visual acuity in the left eye, which had begun 8 hours after cervical spine surgery in the prone position. Her best-corrected visual acuity (BCVA) was 20/20 in the right eye and hand motion in the left eye; a relative afferent pupillary defect was present in the left eye. Ductions and versions were normal with pain in the left eye. The results of slit lamp examination, fundoscopic examination, fluorescein angiography, and optical coherence tomography were unremarkable in both eyes. Brain and orbital magnetic resonance imaging showed no abnormal findings in the visual pathway, such as brain infarction or intracranial artery stenosis. The patient was diagnosed with PION in the left eye. Because postoperative anemia had developed with a rapid decrease in hemoglobin from 14.7 g/dL to 9.9 g/dL, red blood cell (RBC) transfusion was performed together with intravenous high-dose steroid therapy and subcutaneous epoetin alfa injection. After 3 weeks, the patient’s BCVA improved to 20/22 in the left eye.Conclusions: Unilateral PION developed after cervical spine surgery in the prone position. Visual improvement was observed after RBC transfusion, intravenous high-steroid therapy, and subcutaneous epoetin alfa injection.

Vision loss in giant cell arteritis

Almost two-thirds of patients with giant cell arteritis (GCA) develop ocular symptoms and up to 30% suffer permanent visual loss. We review the three most common mechanisms for visual loss in GCA, describing the relevant ophthalmic arterial anatomy and emphasising how ophthalmoscopy holds the key to a rapid diagnosis. The short posterior ciliary arteries supply the optic nerve head, while the central retinal artery and its branches supply the inner retina. GCA has a predilection to affect branches of posterior ciliary arteries. The most common mechanism of visual loss in GCA is anterior arteritic optic neuropathy due to vasculitic involvement of short posterior ciliary arteries. The second most common cause of visual loss in GCA is central retinal artery occlusion. When a patient aged over 50 years has both anterior ischaemic optic neuropathy and a central retinal artery occlusion, the diagnosis is GCA until proven otherwise, and they should start treatment without delay. The least common culprit is posterior ischaemic optic neuropathy, resulting from vasculitic involvement of the ophthalmic artery and its pial branches. Here, the ophthalmoscopy is normal acutely, but MR imaging of the orbits usually shows restricted diffusion in the optic nerve.

Bilateral simultaneous non-arteritic ischaemic optic neuropathy: a rare complication of idiopathic systemic capillary leak syndrome (SCLS)

We report a case of bilateral symmetrical superior visual field defects in a 72-year-old man first reported during the recovery from systemic capillary leak syndrome (SCLS). During the acute illness, he required extensive and prolonged fluid replacement and mechanical ventilation for severe hypotension, shock and multiorgan dysfunction. His visual field defect and optic nerve changes were consistent with a diagnosis of ischaemic optic neuropathy. These remained unchanged over 3 years and he retained excellent 6/7.5 visual acuity bilaterally. We hypothesised the mechanism of bilateral segmental infarction of the optic nerve head to be caused by the hypercoagulable and hypovolaemic state, in addition to pre-existing vascular disease and hypertension. This case highlights the importance of including optic nerve examination in the management plan of SCLS, particularly in individuals with underlying vascular risk factors.

Ocular complications of perioperative anesthesia: a review

Ocular complications associated with anesthesia in ocular and non-ocular surgeries are rare adverse events which may present with clinical presentations vacillating between easily treatable corneal abrasions to more serious complication such as irreversible bilateral vision loss. In this review, we outline the different techniques of anesthetic delivery in ocular surgeries and highlight the incidence and etiologies of associated injuries. The changes in vision in non-ocular surgeries are mistaken for residual sedation or anesthetics, therefore require high clinical suspicion on part of the treating ophthalmologists, to ensure early diagnosis, adequate and swift management especially in surgeries such as cardiac, spine, head and neck, and some orthopedic procedures, that have a comparatively higher incidence of ocular complications. In this article, we review the literature for reports on the clinical incidence of different ocular complications associated with anesthesia in non-ocular surgeries and outline the current understanding of pathophysiological processes associated with these adverse events.

Anterior and posterior ischemic optic neuropathy following liposuction surgery in a previously healthy young woman

A previously healthy 28-year-old female developed bilateral painless vision loss, more prominent in the right eye than in the left, following abdominoplasty and liposuction surgery. Laboratory studies showed severe peri- and post-operative anemia. Over a 5-month follow-up, visual function remained decreased but stable in the right eye and improved in the left eye. This is the second reported case of anterior ischemic optic neuropathy in one eye and posterior ischemic optic neuropathy in the other eye after liposuction.Level of evidence: Level VI, case report study.

Ophthalmology in Critical Care

Ophthalmic disease encountered in the intensive care unit (ICU) has a wide spectrum of prevalence and severity. Prolonged exposure of the cornea is common and preventable. Trauma, glaucoma, infection, vascular disease, and burns are among the potential causes of vision loss. Patients are predisposed to ocular complications by the ICU environment and critical illness itself. Critically ill patients require prioritization of life-sustaining interventions, and less emphasis is placed on ophthalmic disease, leading to missed opportunities for vision-saving intervention. It is therefore imperative for intensivists, nurses, and other providers to have an increased awareness and understanding of the broad range of ocular conditions potentially seen in the ICU.

Intraoperative Fluid Management in Patients Undergoing Spine Surgery: A Narrative Review

Fluid management has been widely recognized as an important component of the perioperative care in patients undergoing major procedures including spine surgeries. Patient- and surgery-related factors such as age, length of the surgery, massive intraoperative blood loss, and prone positioning, may impact the intraoperative administration of fluids. In addition, the type of fluid administered may also affect post-operative outcomes. Published literature describing intraoperative fluid management in patients undergoing major spine surgeries is limited and remains controversial. Therefore, we reviewed current literature on intraoperative fluid management and its association with post-operative complications in spine surgery.

Posterior ischemic optic neuropathy: Perioperative risk factors

Perioperative posterior ischemic optic neuropathy (PION) is a rare but devastating condition. Visual impairment is commonly bilateral, profound, and irreversible. The most frequently associated triggering events are spine surgeries, other orthopedic surgeries, cardiac bypass surgeries, and radical neck dissection. The etiology is multifactorial. The most commonly reported risk factors are severe and prolonged hypotension, anemia, hemodilution, orbital and periorbital edema, direct orbital compression by prone position, and abnormal autoregulation. This review discusses the current literature on perioperative PION and includes a study conducted by our group to investigate the perioperative risk factors of PION in order to better understand the pathogenesis and help identify high-risk patients. Our results provide further corroborating evidence that PION is associated with spinal, cardiovascular, and abdominal surgeries, longer duration of procedure, and facial edema. Anemia and chronic hypertension are frequent risk factors. Treatment for perioperative PION is uncertain and depends largely on the immediate reversal of hemodynamic alterations. Hence, it is important to identify patients at risk and accordingly take prophylactic measures to prevent its occurrence. Optimizing hemoglobin levels, hemodynamic status, and tissue oxygenation is crucial.

Non artheritic bilateral anterior ischaemic optic neuropathy (NAION) as devastating complication following Total Hip Arthroplasty: a case report

INTRODUCTION

Postoperative vision loss (PVL) is an extremely rare complication following major surgical procedures. Patients with systemic hypertension, diabetes, coronary diseases and smokers are generally predisposed to this complication. More frequently, it is caused by ischemic optic neuropathy (ION), central retinal artery occlusion or retinal vein occlusion. Rare cases of unilateral PVL following total joint arthroplasty surgery have been recently described in literature.

CASE REPORT

This case report describes the first reported bilateral non-arteritic anterior ischemic optic neuropathy (NAION), which occurred 3 days following a total hip arthroplasty with a consequent post-operative hypotension.

CONCLUSIONS

Orthopedic surgeons should be aware that in hip joint replacement procedures, selected patients present an higher risk of ION following intra/postoperative hypotension and prolonged surgical times. (www.actabiomedica.it).

Bilateral central retinal/ophthalmic artery occlusion and near-complete ophthalmoplegia after bilateral lung transplant

PURPOSE

Recognize a rare yet existing risk of severe visual loss as a postoperative complication of bilateral lung transplant.

OBSERVATIONS

A 62-year-old male had undergone bilateral lung transplant for end-stage idiopathic pulmonary fibrosis and emphysema overlap syndrome. The operation was initially off-pump; however, during the left lung transplantation, cardiopulmonary bypass conversion was necessary to maintain intraoperative hemodynamic stability. On post-operative day 4, shortly after extubation and full recovery from sedation, the patient reported bilateral no light perception vision. There were no other associated neurologic symptoms. A computed tomographic (CT) of the head, cranial magnetic resonance (MR) scan of the head, MR angiogram of the circle of Willis and neck were negative. Neuro-ophthalmologic examination revealed no light perception vision in both eyes(OU). The pupils were non-reactive to light (amaurotic pupils). The intraocular pressure measured 18 mm Hg OU, and complete bilateral ophthalmoplegia was present. The fundus exam showed bilateral pallid optic disc edema, cherry red spots, with arteriolar attenuation, and mildly dilated and tortuous veins. Stroke work up was negative.

CONCLUSIONS AND IMPORTANCE

A case of post-operative visual loss and ophthalmoplegia carrying significant and permanent quality of life implications. It questions the role disruption of homeostasis during cardiopulmonary bypass contributes for this outcome.

Ischemic Optic Neuropathy

PURPOSE OF REVIEW

Vision is often threatened or lost by acute ischemic damage to the optic nerves. Such pathology most often affects the anterior portion of the nerve and is visible on funduscopic examination. Ischemic optic neuropathy is associated with typical vascular risk factors and with one systemic disease in particular: giant cell arteritis (GCA). This article provides an overview of the three major classes of ischemic optic neuropathy, including information on risk factors, differential diagnosis, evaluation, and management.

RECENT FINDINGS

Optical coherence tomography provides precise anatomic imaging in ischemic optic neuropathy, showing neural loss weeks before it is visible on examination. Refinements of optical coherence tomography reveal optic nerve microvasculature and may assist in understanding pathogenesis and verifying diagnosis. New diagnostic algorithms and cranial vascular imaging techniques help define the likelihood of GCA in patients with ischemic optic neuropathy. Finally, intraocular drug and biological agent delivery holds promise for nonarteritic ischemic optic neuropathy, whereas newer immunologic agents may provide effective steroid-sparing treatment for GCA.

SUMMARY

It is essential to recognize ischemic optic neuropathy upon presentation, especially to determine the likelihood of GCA and the need for immediate steroid therapy. A broad differential diagnosis should be considered so as not to miss alternative treatable pathology, especially in cases with retrobulbar optic nerve involvement.

Ischemic Optic Neuropathy Following Spine Surgery: Case Control Analysis and Systematic Review of the Literature

STUDY DESIGN

Case-control analysis and systematic literature review.

OBJECTIVE

To illustrate the prognosis and perioperative risk factors associated with this condition.

SUMMARY OF BACKGROUND DATA

Ischemic optic neuropathy (ION) is the most common pathological diagnosis underlying postoperative vision loss. It comes in two primary forms-anterior (AION)-affecting the optic disc or posterior (PION) affecting the optic nerve proximal to the disc. Spine surgery remains one of the largest sources of acute perioperative visual loss.

METHODS

We performed a 1:4 case-control analysis (by age and year of surgery) for patients with ION and those who didn't develop ION following spine surgery at our institution. A systematic literature search of Medline, Embase, Scopus from inception to September 2017 as also performed.

RESULTS

We identified 12 cases from our institution. Comparison to 48 matched controls revealed fusion, higher number of operative levels, blood loss, and change in hemoglobin, hematocrit to be significantly associated with ION. Majority were diagnosed with PION (83%, 10/12) and had bilateral presentation (75%, 9/12). Only 30% patients (3/10) demonstrated improvement in visual acuity while the rest remained either unchanged (40%, 4/10) or worsened (20%, 2/10) at last follow-up. Literature review identified 182 cases from 42 studies. Posterior ischemic optic neuropathy (PION) was found in 58.7% (114/194) of cases, anterior ischemic optic neuropathy (AION) in 17% (33/19) and unspecified ION in 24% (47/194). PION was associated with higher odds of severe visual deficit at immediate presentation (odds ratio [OR]: 6.45, confidence interval [CI]: 1.04-54.3, P = 0.04) and last follow-up.

CONCLUSION

PION is the most common cause of vision loss following spine surgery and causes more severe visual deficits compared with AION. Prone spine surgery especially multi-level fusions with longer operative time, higher blood loss, and intraoperative hypotension are most associated with the development of this devastating complication.

LEVEL OF EVIDENCE

3.

Hypotension and Anaemia—A Blinding Combination

We present a case of complete blindness following severe dengue haemorrhagic fever complicated by anaemia and a dialysis-related episode of profound hypotension. The clinical and radiological features indicated an optic neuropathy, most likely ischaemic in aetiology. The features of posterior ischaemic optic neuropathy and differential diagnosis are discussed.

Visual Loss Following Spine Surgery: What Have We Seen Within the Scoliosis Research Society Morbidity and Mortality Database?

STUDY DESIGN

A retrospective review of the Scoliosis Research Society (SRS) morbidity and mortality (M&M) database.

OBJECTIVE

The aim of this study was to investigate visual related complications in spinal deformity patients undergoing spine surgery.

SUMMARY OF BACKGROUND DATA

The SRS compiles surgeon-reported complications into an M&M database, tracking postoperative complications including visual loss, neurological deficits, infections, and death. Limited literature exists on postoperative visual complications, a rare but devastating complication following spine surgery.

METHODS

We utilized the SRS M&M database to determine demographics, perioperative risk factors, and prognosis for visual related complications in spinal deformity patients undergoing corrective spine surgery from 2009 to 2012.

RESULTS

A total of 167,972 spinal deformity patients from 2009 to 2012 were identified with a visual acuity complication (VAC) rate of 0.01%, or 12.5 per 100,000 patients. VAC rates for patients with kyphosis were significantly higher than patients with scoliosis (0.049% vs. 0.010%, P = 0.002) and spondylolisthesis (0.049% vs. 0.005%, P = 0.001). Postoperative visual loss rates significantly decreased from 2010 to 2012 (0.022% vs. 0.004%, P = 0.029). Twenty-one patients identified with VACs had a mean age of 34.8 ± 24.3 years. Two (9.5%) patients had preoperative vision changes, two (9.5%) were diabetic, two (9.5%) had vascular disease, one (4.8%) had a history of thromboembolic disease, and five (23.8%) had hypertension. Extent of VAC was bilateral-partial in four (19.0%), bilateral-total in five (23.8%), unilateral-partial in eight (38.1%), and unilateral-total in three (14.3%) patients. Four (19.0%) patients developed anterior ischemic optic neuropathy, four (19.0%) had posterior ischemic optic neuropathy (PION), five (23.8%) had central retinal artery occlusion, and five (23.8%) developed cortical blindness (CB). Greater than 50% of the VACs occurred on, or before, the first postoperative day. Ten (47.6%) patients recovered complete vision and four (19.0%) improved. All patients with CB and 50% with posterior ischemic optic neuropathy experienced complete resolution.

CONCLUSION

VACs occur in approximately 12.5 per 100,000 deformity patients, with a rate five times higher in patients with kyphosis. More than 50% of these complications occur within 24 hours postoperatively. Nearly half of these complications resolve completely, and another 19% improve postoperatively.

LEVEL OF EVIDENCE

4.

Update on Perioperative Ischemic Optic Neuropathy Associated With Non-ophthalmic Surgery

Perioperative visual loss (POVL) is a rare, serious complication of non-ophthalmic surgeries. Ischemic optic neuropathy (ION), and retinal arterial occlusion (RAO) are the main causes (1, 2). Less frequent are cortical blindness (3), acute glaucoma (4), and choroidal and vitreous hemorrhage (5). ION is the most common cause for which the neurologist or neuro-ophthalmologist is consulted as it is associated either with a normal ophthalmic exam (posterior ION, PION), or less often, with optic nerve (ON) head swelling (anterior ION, AION). The presumed cause is impaired blood supply to the optic nerve (Figure 1). The most common surgical procedures complicated by ION are cardiac surgery and spinal fusion. Retrospective studies, surveys, and case reports are the basis of most knowledge regarding peri-operative ION (poION), with cohort and case-control studies helping to identify candidate risk factors (6, 7). Animal models have provided insight regarding mechanisms (8). This mini-review is an update on the latest advancements regarding poION in non-ophthalmic surgeries in epidemiological, clinical, and animal studies.

Non-arteritic anterior ischaemic optic neuropathy secondary to menorrhagia in a young healthy woman

Non-arteritic anterior ischaemic optic neuropathy (NAION) may develop due to severe anaemia and hypotension which is seen in acute blood loss. The devastating visual loss is often irreversible. We report a case of NAION in a 20-year-old healthy woman, who presented on the third day of a heavy menstrual cycle with hypovolaemic shock. On day 2 of admission, she had sudden right eye blurring of vision at the superior field on awakening from sleep. Funduscopy revealed a pale and swollen right optic disc. There was a dense right superior altitudinal visual field defect. Her haemoglobin level was low (3.6 g/dL), but she refused blood transfusion due to her religious belief (Jehovah's Witness) and opted for conservative management. She later developed right optic atrophy with persistent visual field defect despite an improved haemoglobin level of 10.5 g/dL.

Ocular blood flow in steep Trendelenburg positioning during robotic-assisted radical prostatectomy

PURPOSE

Several ischemic optic neuropathies that occurred during robotic-assisted laparoscopic radical prostatectomy (RALRP) have been reported to be due to the Trendelenburg position, which lowers ocular perfusion pressure (OPP). We examined changes in pulsatile ocular blood flow (POBF) and its correlation with OPP during RALRP in the steep Trendelenburg position.

METHODS

Pulsatile ocular blood flow and intraocular pressure (IOP) were measured in 50 patients by the OBF Langham System 5 times during RALRP. The mean arterial blood pressure (MAP), heart rate, plateau airway pressure, and end-tidal CO2 (EtCO2) at each time point were recorded. Ocular perfusion pressure was calculated from simultaneous IOP and MAP measurements.

RESULTS

Pulsatile ocular blood flow was 15.53 ± 3.32 µL/s at T0, 18.99 ± 4.95 µL/s at T1, 10.04 ± 3.24 µL/s at T2, 11.45 ± 3.02 µL/s at T3, and 15.07 ± 3.81 µL/s at T4. Ocular perfusion pressure was 70.15 ± 5.98 mm Hg at T0, 64.21 ± 6.77 mm Hg at T1, 57.71 ± 7.07 mm Hg at T2, 51.73 ± 11.58 mm Hg at T3, and 64.21 ± 12.37 mm Hg at T4. Repeated-measures analysis of variance on POBF and OPP was significant (p>0.05). This difference disappeared when the correlation between MAP and POBF, EtCO2 and POBF, and EtCO2 and OPP were considered, while correlation between MAP and OPP confirmed the difference. The regression analysis between POBF and OPP showed a statistically significant difference at T0 and T3 (r = 0.047, p = 0.031 and r = 0.096, p = 0.002, respectively).

CONCLUSIONS

Pulsatile ocular blood flow and OPP reached the lowest level at the end of surgery.

Postoperative Posterior Ischemic Optic Neuropathy After Left Far-Lateral Craniectomy for Resection of Craniocervical Meningioma

BACKGROUND

Postoperative posterior ischemic optic neuropathy (PION) is a rare cause of postoperative vision loss, most often seen when surgical patients are placed in the prone position for a prolonged period of time. We report a case of bilateral PION after far-lateral craniectomy in the lateral position.

CASE DESCRIPTION

A 36-year-old man presented with a history of right extremity numbness, weakness, and muscle atrophy, and a craniocervical meningioma was diagnosed. Surgery in the lateral position lasted 9 hours, 52 minutes; the patient had 2 L of blood loss. On postoperative day 1, the patient had bilateral vision loss, which prompted further work-up. Diffusion-weighted imaging of the orbits demonstrated restricted diffusion within the bilateral optic nerves. The clinical presentation of painless vision loss after surgery with these imaging findings led to a diagnosis of PION. At the time of discharge, he had not recovered any visual function.

CONCLUSIONS

This case suggests that PION can occur in the lateral position where there is no direct pressure on the orbits. PION is often not discussed as a potential complication during the preoperative consent process. This case suggests it may be prudent to discuss PION in similar neurosurgical cases. Intraoperative blood transfusion should be considered in prolonged surgeries in the lateral position, where slow blood loss over a long period could be a contributing factor to development of PION.

Head-down Posture in Glaucoma Suspects Induces Changes in IOP, Systemic Pressure, and PERG That Predict Future Loss of Optic Nerve Tissue

PURPOSE

To obtain pilot data on posture-induced changes of intraocular pressure (IOP), systemic pressure, and pattern electroretinogram (PERG) predictive of future optic nerve tissue loss glaucoma suspects (GSs).

METHODS

Mean peripapillary retinal fiber layer thickness (RNFLT) was measured with optical coherence tomography 2 times/year in 28 GS aged 58±8.9 years over 5.0±0.73 years. All patients had a baseline PERG, IOP, and brachial blood pressure measurements in the seated and -10 degrees head-down-body-tilt (HDT) position. Outcome measures were seated/HDT PERG amplitude and phase, IOP, mean arterial blood pressure, and estimated ocular perfusion pressure. An additional group of 11 similarly aged controls aged 56.9±13 years was tested for comparison.

RESULTS

Although all GS had initial RNFLT in the normal range, 9/28 of them developed significant (P<0.05) loss of mean RNFLT [thinners (T)] over the follow-up period as opposed to 19/28 who did not [nonthinners (NT)]. Significant (P<0.05) differences between similarly aged controls, NT, and T were found in PERG amplitude, PERG phase, mean arterial blood pressure, IOP, and ocular perfusion pressure. A nominal logistic regression using baseline PERG and hemodynamic variables was able to distinguish T from NT with an area under receiving operator characteristic of 0.89 (SE, 0.07).

CONCLUSIONS

Baseline PERG, IOP, and systemic blood pressure, together with their changes upon HDT, may have predictive value for future loss of optic nerve tissue in GS. This study supports the rationale for a full-scale clinical trial to identify patients at high risk of development of glaucoma.

Perioperative Vision Loss after Non-Ocular Surgery

Perioperative vision loss (POVL) may cause devastating visual morbidity. A prompt anatomical and etiologic diagnosis is paramount to guide management and assess prognosis. Where possible, steps should be undertaken to minimize risk of POVL for vulnerable patients undergoing high-risk procedures. We review the specific risk factors, pathophysiology, and management and prevention strategies for various etiologies of POVL.

Optical Detection of Early Damage in Retinal Ganglion Cells in a Mouse Model of Partial Optic Nerve Crush Injury

Purpose

Elastic light backscattering spectroscopy (ELBS) has exquisite sensitivity to the ultrastructural properties of tissue and thus has been applied to detect various diseases associated with ultrastructural alterations in their early stages. This study aims to test whether ELBS can detect early damage in retinal ganglion cells (RGCs).

Methods

We used a mouse model of partial optic nerve crush (pONC) to induce rapid RGC death. We confirmed RGC loss by axon counting and characterized the changes in retinal morphology by optical coherence tomography (OCT) and in retinal function by full-field electroretinogram (ERG), respectively. To quantify the ultrastructural properties, elastic backscattering spectroscopic analysis was implemented in the wavelength-dependent images recorded by reflectance confocal microscopy.

Results

At 3 days post-pONC injury, no significant change was found in the thickness of the RGC layer or in the mean amplitude of the oscillatory potentials measured by OCT and ERG, respectively; however, we did observe a significantly decreased number of axons compared with the controls. At 3 days post-pONC, we used ELBS to calculate the ultrastructural marker (D), the shape factor quantifying the shape of the local mass density correlation functions. It was significantly reduced in the crushed eyes compared with the controls, indicating the ultrastructural fragmentation in the crushed eyes.

Conclusions

Elastic light backscattering spectroscopy detected ultrastructural neuronal damage in RGCs following the pONC injury when OCT and ERG tests appeared normal. Our study suggests a potential clinical method for detecting early neuronal damage prior to anatomical alterations in the nerve fiber and ganglion cell layers.

Perioperative Vision Loss in Spine Surgery and Other Orthopaedic Procedures

Perioperative vision loss is a rare complication of orthopaedic surgery and has been documented after spine, knee, hip, and shoulder procedures. It is associated with several ophthalmologic diagnoses, most commonly ischemic optic neuropathy. Although the pathophysiology remains unclear, current evidence suggests that systemic hemodynamic compromise and altered balance of intraocular perfusion contribute to the development of ischemic optic neuropathy. Although vision recovery has been reported, the prognosis of perioperative vision loss is poor, and no proven effective treatment is available. Perioperative vision loss is unpredictable and can occur in healthy patients. Associated risk factors include pediatric or elderly age, male sex, obesity, anemia, hypotension or hypertension, perioperative blood loss, prolonged surgical time, and prone positioning. Preventive strategies include avoiding direct pressure to the eye, elevating the head, optimizing perioperative hemodynamic status, and minimizing surgical time with staged surgical procedures as appropriate.

Perioperative Visual Loss in Spine Fusion Surgery: Ischemic Optic Neuropathy in the United States from 1998 to 2012 in the Nationwide Inpatient Sample

BACKGROUND

Perioperative ischemic optic neuropathy (ION) causes visual loss in spinal fusion. Previous case-control studies are limited by study size and lack of a random sample. The purpose of this study was to study trends in ION incidence in spinal fusion and risk factors in a large nationwide administrative hospital database.

METHODS

In the Nationwide Inpatient Sample for 1998 to 2012, procedure codes for posterior thoracic, lumbar, or sacral spine fusion and diagnostic codes for ION were identified. ION was studied over five 3-yr periods (1998 to 2000, 2001 to 2003, 2004 to 2006, 2007 to 2009, and 2010 to 2012). National estimates were obtained using trend weights in a statistical survey procedure. Univariate and Poisson logistic regression assessed trends and risk factors.

RESULTS

The nationally estimated volume of thoracic, lumbar, and sacral spinal fusion from 1998 to 2012 was 2,511,073. ION was estimated to develop in 257 patients (1.02/10,000). The incidence rate ratio (IRR) for ION significantly decreased between 1998 and 2012 (IRR, 0.72 per 3 yr; 95% CI, 0.58 to 0.88; P = 0.002). There was no significant change in the incidence of retinal artery occlusion. Factors significantly associated with ION were age (IRR, 1.24 per 10 yr of age; 95% CI, 1.05 to 1.45; P = 0.009), transfusion (IRR, 2.72; 95% CI, 1.38 to 5.37; P = 0.004), and obesity (IRR, 2.49; 95% CI, 1.09 to 5.66; P = 0.030). Female sex was protective (IRR, 0.30; 95% CI, 0.16 to 0.56; P = 0.0002).

CONCLUSIONS

Perioperative ION in spinal fusion significantly decreased from 1998 to 2012 by about 2.7-fold. Aging, male sex, transfusion, and obesity significantly increased the risk.

Postoperative posterior ischemic optic neuropathy (PION) following right pterional meningioma surgery

Postoperative visual loss (POVL) is an unpredictable complication of nonocular surgeries. Posterior ischemic optic neuropathy (PION) is particularly feared in spinal surgeries in the prone position. We report a rare case of PION occurring after surgery for a pterional meningioma and discuss the various factors implicated in POVL.

A case of bilateral visual loss after spinal cord surgery

Visual loss is a rare but potentially devastating postoperative complication of prone spinal surgery with a reported incidence of 0.017 to 0.1 percent. We present a case of post-operative bilateral visual loss in a patient who had a laminectomy in prone position under general anesthesia. A 17-year-old male patient with large syringomyelia extending from C2 – T2 level had a surgical procedure done under general anesthesia (GA) in prone position that lasted four hours. After the surgical procedure, the patient presented to the Ophthalmology Clinic of Princess Marina Hospital, with a complaint of visual loss of the right eye followed by left, of one week duration. The patient never had a visual impairment in the past. Physical examination, fundal examination and CT scan revealed no primary cause for the visual loss. In this patient the absence of any finding in the optic disc and the retina and the normal CT scan, suggests that the most likely diagnosis is posterior ischemic optic neuropathy. The patient was treated with prednisolone tablet daily and showed mild improvement in vision.

Postoperative Visual Loss Following Lumbar Spine Surgery: A Review of Risk Factors by Diagnosis

BACKGROUND

Postoperative visual loss (POVL) is a potentially devastating complication of lumbar spine surgery that may lead to significant functional impairment. Although POVL is rare, a review of the literature shows that it is being reported with increasing frequency. A systematic analysis detailing the etiology and prognosis of the 3 main types of POVL has yet to be published. We reviewed potential preoperative and intraoperative risk factors for ischemic optic neuropathy (ION), central retinal artery occlusion (CRAO), and cortical blindness (CB) after lumbar spine surgery.

METHODS

A PubMed and Google literature search was completed in the absence of time constraints. Relevant articles on POVL after spine surgery were identified and reviewed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

We identified 4 large-scale studies that statistically analyzed risk factors for POVL. ION, CRAO, and CB were the most frequently reported POVL types in the literature. Data were abstracted from 19 ION case reports, 3 CRAO case reports, and 5 CB case reports.

CONCLUSIONS

We reviewed the preoperative and intraoperative risk factors for each of the 3 main POVL types, using several published case reports to supplement the limited large-scale studies available. ION risks may be influenced by a longer operative time in the prone position with anemia, hypotension, and blood transfusion. The risk for CRAO is usually due to improper positioning during the surgery. Prone positioning and obesity were found to be most commonly associated with CB development. The prognosis, prevention techniques, and treatment of each POVL type can vary considerably.

Peri-operative visual loss following total knee arthroplasty - A case report: Visual loss following TKA

Perioperative visual loss (POVL) following non-ocular surgery is a rare but significant complication. This report describes a case of ischaemic optic neuropathy following total knee arthroplasty which resulted in permanent blindness.

Using Diffusion-Weighted Magnetic Resonance Imaging to Confirm a Diagnosis of Posterior Ischaemic Optic Neuropathy: Two Case Reports and Literature Review

Posterior ischaemic optic neuropathy is a rare cause of visual loss believed to be due to infarction in the territory of the pial branches of the ophthalmic artery. The disorder most commonly occurs in the context of prolonged surgery or giant cell arteritis, and the absence of clinical signs in the eye means that the diagnosis is one of exclusion. Here, we present two cases studies of patients who developed posterior ischaemic optic neuropathy confirmed by the observation of secondary changes on diffusion-weighted imaging sequences. In the first case visual loss followed robotic pelvic surgery, and in the second case it was associated with multiorgan dysfunction secondary to severe pancreatitis. Our cases demonstrate that in the right clinical context, diffusion-weighted imaging can provide a positive diagnosis of acute posterior ischaemic optic nerve injury in the acute phase.

Visual loss after hip and shoulder arthroplasty, two case reports

PURPOSE

The report of two cases of ischemic optic neuropathy after hip and shoulder arthroplasty under general anesthesia. One of them is the first reported posterior ischemic optic neuropathy after shoulder surgery up to our knowledge.

METHODS

Case reports and review of the literature reporting also data of the anesthesia period.

RESULTS

The first case is a 74-year-old male patient with postoperative visual loss after awakening from hip arthroplasty. He had bilateral visual loss due to an anterior ischemic optic neuropathy with no vascular risk factors associated, probably due to intraoperative blood loss and short periods of drop of his blood pressure. The second case is a 65-year-old man who developed postoperative visual loss because of posterior ischemic optic neuropathy in one single eye after shoulder arthroplasty. To the best of our knowledge there are only three cases reported of ischemic optic neuropathy after shoulder surgery and none of them due to posterior ischemia. This patient had history of vascular risk factors, such as hypertension and diabetes. The repeated tests during the follow up of the patients revealed no significant improvement of their visual function.

CONCLUSIONS

Perioperative visual loss after hip and shoulder surgery is a very rare but fatal complication that is difficult to prevent with a poor visual prognosis. Both anesthetist and surgeon should be aware of this problem.