# Microendoscopic Electrical Impedance Sensing for Real-time Intraoperative Surgical Margin Assessment

> **NIH NIH R01** · DARTMOUTH COLLEGE · 2020 · $470,823

## Abstract

ABSTRACT
The primary objective of surgical therapy for the treatment of patients with cancer is to remove all cancer cells
from within the body, with the secondary objective of maintaining organ function. The primary pathological
metric used to rate the success of a surgical procedure is evaluation of the surgical margin of the resected
tissue specimen, post-operatively. This typically involves cutting the tissue into sections and microscopically
exploring these tissue samples for the presence of cancer cells at the margins. Cancer cells noted at the
margins represent Positive Surgical Margins (PSMs) and suggest that cancer cells were left in the body
following the procedure. As a result, patients with PSMs are often exposed to noxious additional procedures to
eradicate the cancer cells left behind including radiation, chemical, hormonal, and additional surgical therapy;
these all have adverse morbidities that decrease a patient's quality of life. No clinical protocols are routinely
used to intraoperatively assess surgical margin status during surgical procedures. Instead, margins are
evaluated through microscopic assessment of the tissue following the procedure, when it is too late to provide
additional surgical intervention. We aim to develop an intraoperative device able to assess surgical margin
status so that the surgeons can extract additional tissues in real-time and ultimately decrease the rates of
PSMs. While our technology can be applied for most cancer surgeries, we are focusing our efforts on prostate
cancer as these are the highest incidence and cause of death for men and because patients with PSMs
following these procedures have a much higher rate of recurrence than patients that have negative surgical
margins. We have previously shown that the electrical impedance (a property that describes how easily
electrical current passes through a tissue) of tissue is sensitive to a tissue's cellular arrangement and can be
used to distinguish cancer from benign tissue in prostate. We have developed a prototype flexible endoscopic
device capable of imaging the electrical impedance tissue during radical prostatectomy procedures using
Electrical Impedance Tomography (EIT) techniques. This device makes focal measurements of margin status.
Here we aim to take the significant step of constructing an optimized EIT device that can be deployed
laparoscopically (e.g. prostate surgery) to provide an accurate method of intraoperatively identifying positive
surgical margins. We aim to develop this device, develop intraoperative visualization strategies to help guide
surgeons, evaluate the technology in an in vivo study, and validate the technology intraoperatively. By the end
of this program we intend to have developed a low-cost, single use probe that can be deployed in a multi-
center clinical trial to evaluate the efficacy of this technology for intraoperative surgical margin assessment.

## Key facts

- **NIH application ID:** 10052504
- **Project number:** 1R01CA237654-01A1
- **Recipient organization:** DARTMOUTH COLLEGE
- **Principal Investigator:** Ryan Joseph Halter
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $470,823
- **Award type:** 1
- **Project period:** 2020-07-15 → 2025-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10052504

## Citation

> US National Institutes of Health, RePORTER application 10052504, Microendoscopic Electrical Impedance Sensing for Real-time Intraoperative Surgical Margin Assessment (1R01CA237654-01A1). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10052504. Licensed CC0.

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