• Users Online: 315
  • Print this page
  • Email this page


 
 Table of Contents  
CASE REPORT
Year : 2023  |  Volume : 3  |  Issue : 1  |  Page : 133-135

Perioperative ischemic optic neuropathy following subtotal petrosectomy: A rare complication of ear surgery causing vision loss


1 Department of Retina and Vitreous, Rajan Eye Care Hospital Pvt Ltd., Chennai, Tamil Nadu, India
2 Madras ENT Research Foundation Pvt Ltd., Chennai, Tamil Nadu, India

Date of Submission18-Jul-2022
Date of Acceptance09-Sep-2022
Date of Web Publication20-Jan-2023

Correspondence Address:
Arthi Mohankumar
Rajan Eye Care Hospital, 5, Vidyodaya Second Street, T. Nagar, Chennai - 600017, Tamil Nadu
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijo.IJO_1697_22

Rights and Permissions
  Abstract 


Perioperative vision loss (POVL) is unilateral or bilateral, partial or complete loss of vision occurring in patients undergoing non-ophthalmic surgical procedures. They are commonly known to occur following cardiac, spine, and other orthopedic surgeries. The exact mechanism is not known and a variety of systemic and intraoperative risk factors including patient positioning, fluid loss, and use of vasopressors are implicated. The most common cause of POVL are ischemic optic neuropathies which occur due to disturbance in blood flow to the optic nerve. In this case report, we describe a case of perioperative ischemic optic neuropathy occurring following inner ear surgery and its management.

Keywords: Ischemic optic neuropathy, perioperative optic neuropathy, perioperative vision loss


How to cite this article:
Mohankumar A, Rajan M, Aravind V, Nandhan R, Kameswaran M. Perioperative ischemic optic neuropathy following subtotal petrosectomy: A rare complication of ear surgery causing vision loss. Indian J Ophthalmol Case Rep 2023;3:133-5

How to cite this URL:
Mohankumar A, Rajan M, Aravind V, Nandhan R, Kameswaran M. Perioperative ischemic optic neuropathy following subtotal petrosectomy: A rare complication of ear surgery causing vision loss. Indian J Ophthalmol Case Rep [serial online] 2023 [cited 2023 Feb 1];3:133-5. Available from: https://www.ijoreports.in/text.asp?2023/3/1/133/368161



Perioperative vision loss (POVL) can occur infrequently following systemic surgical procedures like head and neck surgeries, vascular, gynecological procedures, and liposuction.[1] The most common cause of POVL is perioperative ischemic optic neuropathies (poION) which are a group of optic nerve head disorders arising due to disturbances in the blood supply to the optic nerve. Other causes of POVL include retinal artery occlusion, external corneal injuries, and acute glaucoma. poION is commonly present as posterior ischemic optic neuropathy (PION) or as anterior ischemic optic neuropathy (AION).[2] Any high-risk patient should have a preliminary ophthalmic assessment done once the patient is awake and promptly referred to an ophthalmologist in case of any symptoms.


  Case Report Top


A 40-year-old female underwent left subtotal petrosectomy, transotic cerebrospinal fluid (CSF) leak repair, and facial nerve decompression under general anesthesia (GA) for recurrent chronic otitis media and mastoiditis with extensive petrous cholesteatoma, causing grade 4 lower motor neuron (LMN) facial paresis [Figure 1]. The patient was placed in the supine position with sand back under the shoulders and head turned to the right for lateral skull base approach. The surgery started with a conventional subtotal petrosectomy approach for extensive cholesteatoma followed by radical mastoidectomy via transotic approach. Matrix on the dura, facial nerve, around the internal carotid artery (ICA), and jugular bulb was cleared in piecemeal. Residual osteomyelitic bone around the ICA was left in situ to avoid injury. CSF leak repair and facial nerve anastomosis was done. Vascularization of the cavity was done by rotating the temporoparietal muscle flap, and multilayered closure was done with fascia lata, tissue glue, and fat followed by blind sac closure. The total blood loss was 2.5 liters. Duration of surgery was 8 hours during which adequate intraoperative hemodynamics was maintained by the anesthetist by whole blood and colloidal transfusions. She was a diabetic with good glycemic control. The surgery was uneventful but she complained of blurring of vision in her left eye (OS) post recovery from GA for which urgent ophthalmology referral was sought. On examination, her best-corrected visual acuity (BCVA) in the right eye was 6/6, N6 and left eye 6/18, N9. Anterior segment examination revealed lagophthalmos, punctate epithelial erosions (PEE), and grade 2 relative afferent pupillary defect (RAPD) in OS and was unremarkable in OD. Color vision was defective in OS and automated perimetry by Humphrey Field analyzer (HFA) 30-2 revealed an altitudinal field defect in OS. Dilated fundus examination showed segmental disc edema with disc hemorrhages in OS [Figure 2]a and was otherwise unremarkable. Examination of OD was normal. A diagnosis of OS AION with left grade 4 LMN facial paresis causing exposure keratitis was made. Magnetic resonance imaging (MRI) of the brain showed perineural enhancement of the left optic nerve based on which the patient was treated with methyl prednisolone 1 g IV for three days followed by oral prednisolone 1 mg/kg bodyweight for two weeks. On day 3, there was minimal reduction in disc hyperemia with persistence of disc hemorrhages [Figure 2]b. She was also advised lid taping and topical lubricants for her exposure keratitis and lagophthalmos. One month later, her BCVA in OS was 20/30. Examination revealed adequate lid closure, resolved PEEs, and persisting RAPD. Color vision was normal, field defect persisted, and fundus revealed resolution of disc edema with pallor in OS [Figure 2]c. The patient was counselled and was referred back to the otorhinolaryngologist for further management of inner ear disease. She was kept on IV antibiotics and monitored for over next 2 weeks and surgical site healed well. Her repeat imaging showed no evidence of any residual or recurrence of cholesteatoma in the petrous temporal bone at one year of follow-up.
Figure 1: Plain axial computed tomography (CT) scan of brain showing destruction of the petrous temporal bone (white arrow) by extensive left inner ear cholesteatoma

Click here to view
Figure 2: Color optic disc image (a) showing blurring of margins, disc hyperemia, and hemorrhages at presentation. Image (b) showing resolution of hyperemia but persistence of disc hemorrhages following IV steroid therapy. Component (c) shows complete resolution of disc edema and hemorrhages with secondary optic atrophy

Click here to view



  Discussion Top


Incidence of poION is documented to be between 1/60,000 and 1/125000 with the highest incidence following spine surgery. It has been postulated to be due to decreased oxygenation of the optic nerve, enough to cause an ischemic insult.[3] Intraoperative risk factors include decreased systemic blood pressure, blood or fluid loss, anemia or hemodilution, prone positioning, flow of CSF to optic nerve, abnormal autoregulation in optic nerve, and use of vasopressors. Systemic risk factors include hypertension, hyperlipidemia, diabetes, prolonged duration of surgery, and prone positioning. AION and PION have also been reported in the setting of massive fluid replacement which could result in an internal “compartment syndrome” compressing the axons as they transit the lamina cribrosa.[4] The disturbances in vision and/or color vision is usually documented once the patient recovers from anesthesia. Patients may have RAPD with a field defect corresponding to the ischemic insult to the optic nerve. Fundus examination is essentially normal in patients with PION, whereas in AION disc edema, disc hemorrhages and cotton wool spots may be present in the fundus in acute stages, which resolve with a secondary optic atrophy. MRI of the optic nerves is usually normal and may show perineural nerve enhancement or edema. Visual evoked potentials are abnormal. The American Society of Anesthesiologists (ASA) registry has the largest record of poION[5] and have laid down recommendations regarding its treatment and management. Intraoperative optimization of hematocrit, fluid loss, and hemodynamic status is essential. The role for anti-platelet agents, steroids, or intraocular pressure (IOP)-lowering agents in the management of poION is still debated. Diuretics such as mannitol or furosemide may help in reducing IOP and perineural edema. Steroids may also be used for reduction in perineural inflammation and edema, thereby stabilizing blood flow to the optic nerve head.

In our patient, a multitude of factors may have contributed to the occurrence of poION. Operative risk factors like prolonged surgery, patient positioning causing kinking or spasm of the carotid vessel in the neck, hypovolemic vasospasm, fluid imbalance, blood transfusion–induced thromboembolism, and intraoperative use of vasopressors for BP control could have led to the development of poION. Local surgical predisposing factors including direct mechanical, vibrational, and mechanical trauma to the vertical segment of ICA in the petrous temporal bone during disease clearance could have also led to thromboembolism or vasospasm. Cholesteatoma around the ICA and its dissection from the ICA in the petrous temporal bone could also have induced a septic thromboembolism. Though the ICA is a robust and resilient structure within the temporal bone which can sustain insult during routine skull base surgeries, such complications may rarely occur.


  Conclusion Top


Through this case report, a rare complication of inner ear surgery causing ischemic optic neuropathy has been highlighted. The authors could not identify any other reports of POVL following inner ear surgery. Hence, this case would be beneficial to both otorhinolaryngologists and ophthalmologists alike, whereby they can anticipate and prepare to manage this adverse event in a systematic and efficient way. It is prudent to meticulously counsel all the patients undergoing extensive ear and skull base surgeries, mentioning that one of the rare complications of surgery could be blindness, which needs urgent multi-disciplinary management.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Roth S, Moss HE. Update on perioperative ischemic optic neuropathy associated with non-ophthalmic surgery. Front Neurol 2018;9:557.  Back to cited text no. 1
    
2.
Wang MY, Brewer R, Sadun AA. Posterior ischemic optic neuropathy: Perioperative risk factors. Taiwan J Ophthalmol 2020;10:167-73.  Back to cited text no. 2
  [Full text]  
3.
Holy SE, Tsai JH, McAllister RK, Smith KH. Perioperative ischemic optic neuropathy: A case control analysis of 126,666 surgical procedures at a single institution. Anesthesiology 2009;110:246-53.  Back to cited text no. 3
    
4.
Grover V, Jangra K. Perioperative vision loss: A complication to watch out. J Anaesthesiol Clin Pharmacol 2012;28:11-6.  Back to cited text no. 4
[PUBMED]  [Full text]  
5.
Lee LA, Newman NJ, Wagner TA, Dettori JR, Dettori NJ. Postoperative ischemic optic neuropathy. Spine (Phila Pa 1976) 2010;35:S105-16.  Back to cited text no. 5
    


    Figures

  [Figure 1], [Figure 2]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Case Report
Discussion
Conclusion
References
Article Figures

 Article Access Statistics
    Viewed40    
    Printed4    
    Emailed0    
    PDF Downloaded8    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]