Intraoperative Laser Speckle Contrast Imaging to Assess Blood Flow During Neurosurgery (LSCI-NSURG)

Cerebral blood flow (CBF) is of paramount importance to human brain function, as the brain relies on a continuous blood supply to meet its energy needs. Blockage of a cerebral blood vessel during neurosurgery, even if transient and short-lived, may result in irreversible brain tissue damage (i.e. stroke) and loss of cortical function, if not identified quickly enough.

Laser speckle contrast imaging (LSCI) has been demonstrated to provide the ability to visualize flow in vessels in real time and continuously without the need for contrast agents. In LSCI, the tissue of interest is illuminated with low power laser light at red or near infrared wavelengths and the light reflected from the tissue surface is imaged onto a camera. The resulting images are laser speckle patterns and a computer processes the images to produce speckle contrast images, which are images of the motion within the field of view (ie, blood flow).

The purpose of this clinical investigation is to assess the usefulness and accuracy of LSCI compared to ICGA and/or FA during neurovascular surgery. LSCI videos will be recorded automatically intraoperatively in each patient before, during, and after ICGA and/or FA in the same surgical field of view to guarantee comparability of the methods.

Study Overview

• Status: Completed
• Conditions: Glioma; Aneurysm; Metastasis; Meningioma; AVM; Dural Arteriovenous Fistula
• Intervention / Treatment: Device: Laser speckle contrast imaging (LSCI)

Detailed Description

Cerebral blood flow (CBF) is of paramount importance to human brain function, as the brain relies on a continuous blood supply to meet its energy needs. Blockage of a cerebral blood vessel during neurosurgery, even if transient and short-lived, may result in irreversible brain tissue damage (i.e. stroke) and loss of cortical function, if not identified quickly enough.

Neurosurgery involves the treatment of blood-vessel related pathologies within the brain, like intracranial aneurysms, arteriovenous malformations and dural arteriovenous fistulas, but also the handling of vessels during brain tumor resections. For these operations, assessment of flow in vessels is of paramount importance. So far, the surgeon can not "see" blood flowing inside the artery or vein. Real-time flow visualization during surgery could help neurosurgeons better understand the consequences of vascular occlusion events during surgery, recognize potential adverse complications, and thus prompt timely intervention to reduce the risk of stroke. The current standard for visualizing flow in arteries during surgery is indocyanine green angiography (ICGA) and fluorescein angiography (FA), which involves administering a bolus of fluorescent dye intravenously and imaging the wash-in of the dye to determine which vessels are perfused. Both ICGA and FA provide only a punctual view of perfusion over several seconds, being far away from a continuous assessment.

Laser speckle contrast imaging (LSCI) has been demonstrated to provide the ability to visualize flow in vessels in real time and continuously without the need for contrast agents. In LSCI, the tissue of interest is illuminated with low power laser light at red or near infrared wavelengths and the light reflected from the tissue surface is imaged onto a camera. The resulting images are laser speckle patterns and a computer processes the images to produce speckle contrast images, which are images of the motion within the field of view (ie, blood flow).

With these properties LSCI has the potential to deliver for the first time continuous visualisation of blood flow in large and small vessels and to overcome limitations of ICGA and FA. LSCI is an established technique for studies of CBF and has predominantly been used to study microcirculation of the cerebral cortex during neurosurgical procedures. However, the spatial resolution in the clinical setting and its accuracy compared to ICGA and FA are unclear.

The purpose of this clinical investigation is to assess the usefulness and accuracy of LSCI compared to ICGA and/or FA during neurovascular surgery. LSCI videos will be recorded automatically intraoperatively in each patient before, during, and after ICGA and/or FA in the same surgical field of view to guarantee comparability of the methods.

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Bern, Switzerland, 3010
    • Department of Neurosurgery

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 14 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Vascular pathology of the brain or brain tumors requiring elective microsurgical treatment (e.g., aneurysm, arteriovenous malformation, dural arteriovenous fistula, glioma, meningioma, metastasis)
• Adults (18 years or older)
• Informed consent signed by the subject

Exclusion Criteria:

• Patients lacking capacity to consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Laser speckle contrast imaging (LSCI); LSCI videos will be recorded automatically intraoperatively in each patient before, during, and after ICGA and/or FA in the same surgical field of view to guarantee comparability of the methods.	Device: Laser speckle contrast imaging (LSCI); LSCI videos will be recorded automatically intraoperatively in each patient before, during, and after ICGA and/or FA in the same surgical field of view to guarantee comparability of the methods.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Agreement of ICG/FA and LSCI-findings	Agreement of ICG/FA and LSCI-findings determinating flow in exposed vessels classified as no flow, delayed flow, normal flow	During surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Vessels examined with Laser speckle contrast imaging (LSCI)	Vessels examined with Laser speckle contrast imaging (LSCI)	During surgery
Vessels examined with Indocyanine green angiography (ICGA)	Vessels examined with Indocyanine green angiography (ICGA)	During surgery
Vessels examined with Fluorescein angiography (FA)	Vessels examined with Fluorescein angiography	During surgery

Collaborators and Investigators

• Sponsor: University Hospital Inselspital, Berne
• Investigators: Principal Investigator: Andreas Raabe, MD, Study Principal Investigator

Study record dates

Study Major Dates

• Study Start (Actual): February 1, 2022
• Primary Completion (Actual): March 11, 2022
• Study Completion (Actual): March 11, 2022

Study Registration Dates

• First Submitted: August 24, 2021
• First Submitted That Met QC Criteria: August 24, 2021
• First Posted (Actual): August 31, 2021

Study Record Updates

• Last Update Posted (Actual): April 12, 2022
• Last Update Submitted That Met QC Criteria: April 11, 2022
• Last Verified: April 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Nervous System Diseases; Neoplasms by Histologic Type; Neoplasms; Neoplasms by Site; Congenital Abnormalities; Neoplasms, Nerve Tissue; Pathological Conditions, Anatomical; Central Nervous System Neoplasms; Nervous System Neoplasms; Cardiovascular Abnormalities; Neoplasms, Vascular Tissue; Nervous System Malformations; Vascular Malformations; Meningeal Neoplasms; Arteriovenous Malformations; Vascular Fistula; Fistula; Aneurysm; Meningioma; Arteriovenous Fistula; Central Nervous System Vascular Malformations
• Other Study ID Numbers: LSCI-NSURG

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No