Clinical trial NCT04068220: Intraoperative Continuous Flash Visual Evoked Potentials Monitoring During Endoscopic Skull Base Surgery
Official title: Intraoperative Continuous Flash Visual Evoked Potentials Monitoring During Minimally Invasive Endoscopic Skull Base Surgery, a Novel Approach to Improve Patient Outcome
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Chiasmal; Lesion
Prechiasmal; Lesion
Keywords: chiasmal, prechiasmal, lesion, endoscopic skull base surgery
Lead sponsor: Ottawa Hospital Research Institute
Sponsor class: OTHER
Collaborators: name: Ottawa Hospital Research Institute
First posted: 2019-08-28
Enrollment: 40
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: PREVENTION

Brief summary: Skull base surgeries performed in areas involving the visual pathway are associated with varying levels of postoperative visual dysfunction. The goal of intraoperative FVEP monitoring is to detect and prevent intraoperative visual pathway injury.

Detailed description: Skull base surgeries performed in areas involving the visual pathway are associated with varying levels of postoperative visual dysfunction. For instance, surgical resection of suprasellar meningiomas has been shown to worsen visual function in 14 - 28% of patients and surgical resection of craniopharyngiomas worsen visual function in 3 - 11.5% of patients. Manipulation of the optic nerve and interference with the microvasculature during surgical dissection is thought to be responsible for the visual loss.

Through intraoperative monitoring and prompt identification of flash visual evoked potentials (FVEPs) deterioration, corrective surgical measures could be undertaken to improve or stabilize postoperative visual dysfunction. Furthermore, intraoperative FVEPs monitoring may influence surgical decision-making thus contributing to predict and prevent postoperative visual dysfunction as well as allowing more total resection of a tumour when the monitoring is stable.

This study's aim is to determine if intraoperative continuous FVEPs monitoring can predict and prevent or minimize possible visual pathway injury that may appear during minimally invasive endoscopic skull base surgery.

Eligibility criteria: Inclusion Criteria:

* Adult population (18 years and older), admitted to The Ottawa Hospital (TOH)-Civic Campus for a chiasmal or pre-chiasmal lesion, undergoing first time minimally invasive endoscopic skull base surgery
* Patient able to personally sign and date the informed consent document
* Patients will be selected based on the surgeon's determination that:

  1. The visual system will be at risk of iatrogenic injury
  2. The intraoperative FVEPs monitoring could rapidly detect this injury AND
  3. Corrective measures could be taken during surgery to reverse it.

Exclusion Criteria:

* patients having a pre-existent retinal disease, cardiac pacemaker
* contraindication for total intravenous anaesthesia (TIVA)
* unable to complete required pre and post-operative visual assessment or unable to complete their post-operative follow-up visits at TOH-Civic Campus
* anticipated goggle movement related to reflection of the frontal skin flap
* preoperative visual deficits (e.g., profound deficits in visual acuity or dense visual field loss)

Primary outcomes:
measure: Examine the feasibility of detecting iatrogenic visual pathway injury by using intraoperative monitoring of continuous FVEPs in minimally invasive endoscopic skull base surgery.
timeFrame: 1 year
Secondary outcomes:
measure: Determine sensitivity and specificity as well as positive and negative predictive value of intraoperative monitoring of continuous FVEPs in minimally invasive endoscopic skull base surgery.
timeFrame: 1 year
measure: Report the adverse events of intraoperative monitoring continuous FVEPs
timeFrame: 1 year
Other outcomes:
Locations:
city: Ottawa
country: Canada
facility: The Ottawa Hospital - Civic Campus
state: Ontario
Study officials:
affiliation: Ottawa Hospital Research Institute
name: Fahad Alkherayf, MD MSc FRCSC
role: PRINCIPAL_INVESTIGATOR
References: