Improving Maximal Safe Brain Tumor Resection with Photoacoustic Remote Sensing Microscopy

TL;DR

This paper introduces a rapid, non-contact optical imaging technique called PARS that provides real-time, histology-like images of brain tissues, aiding surgeons in maximizing tumor resection while reducing diagnostic time.

Contribution

The study presents a novel all-optical, label-free PARS microscope capable of high-throughput, real-time histological imaging of brain tissues for intraoperative guidance.

Findings

PARS images are comparable to standard histopathology in quality and contrast.

The technique enables rapid assessment of brain tissues without staining.

PARS can potentially improve surgical outcomes by guiding maximal tumor resection.

Abstract

Malignant brain tumors are among the deadliest neoplasms with the lowest survival rates of any cancer type. In considering surgical tumor resection, suboptimal extent of resection is linked to poor clinical outcomes and lower overall survival rates. Currently available tools for intraoperative histopathological assessment require an average of 20 minutes processing and are of limited diagnostic quality for guiding surgeries. Consequently, there is an unaddressed need for a rapid imaging technique to guide maximal resection of brain tumors. Working towards this goal, presented here is an all optical non-contact label-free reflection mode photoacoustic remote sensing (PARS) microscope. By using a tunable excitation laser, PARS takes advantage of the endogenous optical absorption peaks of DNA and cytoplasm to achieve virtual contrast analogous to standard hematoxylin and eosin (H and E) staining. In conjunction, a fast 266 nm excitation is used to generate large grossing scans and rapidly assess small fields in real-time with hematoxylin-like contrast. Images obtained using this technique show comparable quality and contrast to the current standard for histopathological assessment of brain tissues. Using the proposed method, rapid, high-throughput, histological-like imaging was achieved in unstained brain tissues, indicating PARS utility for intraoperative guidance to improve extent of surgical resection.