Evaluation of the CONVIVO System

Dartmouth Health

Status: Enrolling

Conditions: Glioblastoma; Brain Metastases; Glial Tumor; Meningioma; Schwannoma; Pituitary Tumor

Treatments: Other: Conventional histologic evaluation; Diagnostic Test: CONVIVO system

Study type: Interventional

Funder types: Other; Industry

Identifiers

NCT05139277

D20056

Details and patient eligibility

About

The primary objective of this study is to evaluate the diagnostic performance of the CONVIVO confocal endomicroscope in discriminating between normal and abnormal tissue in vivo during brain tumor surgery. The interpretation of intraoperative images obtained in situ will be tested against conventional histologic evaluation of targeted biopsies from imaged tissue. The study team hypothesize that there will be a high degree of correlation between images obtained with the CONVIVO system and conventional histologic interpretation.

Full description

The surgical resection of brain tumors is an integral component of modern neuro-oncology. . Extent of resection has been found to be associated with increased overall and progression free survival, with the greatest benefit occurring in the setting of a complete or gross total resection. Unfortunately, there are a number of obstacles unique to brain tumors that may limit the extent of resection. A number of advancements in neurosurgical oncology have emerged to improve the extent of tumor resection while decreasing operative morbidity and mortality. Confocal reflectance microscopy is a routine technique used to visualize tissues without fixation or staining used in classical histological techniques. Laser scanning confocal microscopy (LSCM) is an optical fluorescence imaging modality used for imaging thick in vivo and ex vivo tissues. Clinically available confocal endomicroscopy systems contain lasers with precise excitation wavelengths and dichroic filters for detecting appropriate emission wave lengths. The studies completed to date do not evaluate the ability of confocal microscopy to discriminate between normal and abnormal tissue at the margins during surgical resection. This is the first of such in vivo feasibility studies that aims to demonstrate this claim of the CONVIVO system.

The images acquired with the CONVIVO system following administration of fluorescein will be compared to conventional histologic specimens from corresponding biopsies. This is a planned single center study. This study is designed to assess the diagnostic accuracy of the CONVIVO system compared with gold-standard histopathology in tissue that has already been identified for resection. The device will not be used to inform surgical decision making, nor will tissue that would not otherwise be resected be biopsied for research purposes.

This study will rely on study investigators, all physicians at Dartmouth-Hitchcock, to identify subjects. Written consent is required for participation in the study.. There are no specific medical risks to patients associated with the use of CONVIVO. It is not anticipated that there are immediate or direct benefits to patients participating in this study. The CONVIVO imaging data acquired during the procedure will be initially stored on the device's hard drive and later securely uploaded to an encrypted Dartmouth-Hitchcock server. Patients will have the ability to maintain their privacy with minimal disruption or contact by the study team. Additionally, the PI or other investigators will have interactions with the patient as part of their routine clinical care. Participants are free to withdraw from participation in the study at any time upon request.

Enrollment: 30 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Adult patients (age>18)
• Adults presenting with suspected intracranial gliomas (including glioblastoma), cerebral metastasis, meningiomas, acoustic neuromas, and pituitary adenomas, who are surgical candidates
• Adults able to provide informed consent.

Exclusion criteria

• Pregnancy
• Children (age <18 years)
• Fluorescein sodium (FNa) allergy

Trial design

Primary purpose: Diagnostic

Allocation: Non-Randomized

Interventional model: Single Group Assignment

Masking: None (Open label)

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30 participants in 2 patient groups

CONVIVO system

Experimental group

Description:

During tumor resection, study investigators trained in the use of the system will determine when the CONVIVO imaging system will be used for in vivo¬ imaging. At this point 5 mg/kg of fluorescein will be administered intravenously by an anesthesia provider over one minute.Approximately 2-5 minutes following administration of FNa in situ imaging will be performed by the participating surgeon ensuring proper technique.

Treatment:

Diagnostic Test: CONVIVO system

Conventional histologic evaluation

Other group

Description:

Following image acquisition, the tissue region imaged with the CONVIVO system will then be biopsied using biopsy forceps. This will be passed immediately off the surgical field as a research specimen and provided to a member of the research team to be prepared for conventional histologic evaluation. The specimen will be labeled with the deidentified subject and sample number. This sequence will then be repeated for each successive sample.

Treatment:

Other: Conventional histologic evaluation