Evidence map›Paper›PMID 41869272›Full record

ArticleJournal of biomedical optics2026

Endoscopic iso-pathlength self-calibration for direction-resolved retrieval of tissue optical properties.

Natanel Ovadia, Hamootal Duadi, Dror Fixler

Abstract read
In one paragraph

Article in Journal of biomedical optics, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

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5 · Who and what money

Authors and funding

3 authors.

Natanel OvadiaBar Ilan University, Faculty of Engineering and the Institute of Nanotechnology and Advanced Materials, Ramat Gan, Israel.
Hamootal DuadiBar Ilan University, Faculty of Engineering and the Institute of Nanotechnology and Advanced Materials, Ramat Gan, Israel.
Dror FixlerTel Aviv University, Jan Koum Center for Nanoscience and Nanotechnology, Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv, Israel.ORCID https://orcid.org/0000-0003-0963-7908

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Significance: Medical examination of human tissue is preferably performed by imaging the tissue surface. Optical imaging techniques are limited by low penetration depth due to high tissue scattering, whereas sensing techniques can detect changes deeper inside the tissue. Near-infrared sensing methods such as oximetry and fNIRS are already used clinically but have not yet been applied in endoscopy. Aim: We investigate the existence of iso-pathlength (IPL) points in endoscopic geometry, with the goal of extending the concept of IPL points from cylindrical and half-infinite geometries into hollow cylindrical tissue relevant to endoscopy. In addition, we demonstrate the ability to extract the absorption properties of a tissue at this structure by the IPL and demonstrate it by Approach: The IPL point is a unique position in the full scattering profile, independent of tissue scattering and dependent only on the tissue absorption and geometry. We studied two directions in cylindrical endoscopic geometry: azimuthal and longitudinal. First, diffusion theory with extrapolated zero-boundary conditions was applied to predict IPL positions. These predictions were then tested using Monte Carlo simulations of photon distribution and validated experimentally using phantoms with cylindrical air holes measured by endoscopy. Finally, using the experimentally identified IPL point and applying the same procedure to a standard phantom, a hemoglobin-agar phantom, and chicken breast tissue, we were able to estimate the absorption coefficient of the chicken tissue. Results: Both azimuthal and longitudinal IPL points were identified. The experimental azimuthal IPL point was found at an angle of Conclusions: The demonstration of IPL points in endoscopic geometry provides a new framework for depth-resolved optical sensing in hollow cylindrical tissues. This approach may enable self-calibrated absorption measurements and open the way for improved diagnostic tools in the digestive system, esophagus, and other hollow organs where conventional endoscopy lacks depth information.

Indexed as

EndoscopyOptical ImagingAnimalsCalibrationChickensComputer SimulationHumansMonte Carlo MethodPhantoms, ImagingScattering, Radiationchicken breastendoscopyiso-pathlength pointMonte Carlo simulationphantomstissue optical properties

Identifiers

PMID41869272
PMCPMC13005598

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.