Intraoperative Continuous Flash Visual Evoked Potentials Monitoring During Endoscopic Skull Base Surgery

NCT ID: NCT04068220

Last Updated: 2020-09-18

Basic Information

• Recruitment Status: UNKNOWN
• Clinical Phase: NA
• Total Enrollment: 40 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2020-03-02
• Study Completion Date: 2021-12-31

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.

Conditions

Chiasmal; Lesion; Prechiasmal; Lesion

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: PREVENTION
• Blinding Strategy: NONE

Study Groups

Intraoperative FVEPs monitoring

adult patients admitted to TOH - Civic Campus, for chiasmal or pre-chiasmal lesions undergoing a first time minimally invasive endoscopic skull base surgery.

Group Type: OTHER

intraoperative FVEPs monitoring

Intervention Type: OTHER

During the surgery, a pair of goggles (similar to the swimming goggles) will be placed on patient's closed eyes. The goggles equipped with red LEDs will apply no pressure or minimal pressure on patient's closed eyes. Patient's left eye then right eye will be stimulated with flashing red light emitted by the goggles. Two subdermal needle electrodes will be placed under the skin behind patient's ears, and one subdermal needle electrode will be placed under the skin above the bridge of patient's nose. The two electrodes placed behind patient's ears, will record intraoperative flash visual evoked potentials (FVEPs) resulted from red light stimulation of patient's visual pathway through the eyes and the electrode above the bridge of the nose will record, at the same time, the activity of each eye's retina.

Interventions

intraoperative FVEPs monitoring

During the surgery, a pair of goggles (similar to the swimming goggles) will be placed on patient's closed eyes. The goggles equipped with red LEDs will apply no pressure or minimal pressure on patient's closed eyes. Patient's left eye then right eye will be stimulated with flashing red light emitted by the goggles. Two subdermal needle electrodes will be placed under the skin behind patient's ears, and one subdermal needle electrode will be placed under the skin above the bridge of patient's nose. The two electrodes placed behind patient's ears, will record intraoperative flash visual evoked potentials (FVEPs) resulted from red light stimulation of patient's visual pathway through the eyes and the electrode above the bridge of the nose will record, at the same time, the activity of each eye's retina.

Intervention Type: OTHER

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)

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Ottawa Hospital Research Institute

OTHER

Sponsor Role: collaborator

Fahad AlKherayf

OTHER

Sponsor Role: lead

Responsible Party

Fahad AlKherayf

Associate Scientist

Responsibility Role: SPONSOR_INVESTIGATOR

Principal Investigators

Fahad Alkherayf, MD MSc FRCSC

Role: PRINCIPAL_INVESTIGATOR

Ottawa Hospital Research Institute

Locations

The Ottawa Hospital - Civic Campus

Ottawa, Ontario, Canada

Site Status: RECRUITING

Countries

Canada

Central Contacts

Ioana D Moldovan, MD MSc

Role: CONTACT

imoldovan@ohri.ca

613-798-5555 ext. 18574

Facility Contacts

Ioana D Moldovan, MD MSc

Role: primary

imoldovan@ohri.ca

613-798-5555 ext. 18574

Related Links

http://www.ottawahospital.on.ca

The Ottawa Hospital website

Other Identifiers

20190533 - 01H

Identifier Type: -

Identifier Source: org_study_id