Multiphoton imaging for clinical endoscopy

Chris Xu

School of Applied and Engineering Physics Cornell University

Multiphoton endoscopy

Core Technology • Platform technology: in vivo clinical detection of

disease states

• Prototype endoscopes: cancer detection, image guided surgery and therapeutics

• Supported by an extensive portfolio of issued and pending patents: – 18 issued patents in US, Europe, China, Japan – 15 applications pending in US, EU, China, Japan – Several inventions in the pipeline

• Unique advantage: in vivo, chemically specific, high

spatial resolution, 3 dimensional imaging with or WITHOUT stain.

Current Medical Endoscopy and Biopsy

• Low resolution optical viewing • Invasive tissue removal • Delayed diagnosis

Real Time Tissue Diagnostics by Multiphoton Endoscopy

In vivo, chemically specific, high spatial resolution, 3-dimensional imaging with or WITHOUT stain.

Low magnification optical viewing

High magnification multiphoton imaging

• High spatial resolution • No tissue removal • Immediate assessment

20 µm 2 mm

One Photon Two Photon

Fluorescein solution

focal plane focal plane

Signal I∝ 2Signal I∝

Multiphoton enabling 3-dimensional, deep tissue imaging

Arteriole Heart Choroid Plexus / Pineal Gland

Retinoids

NADH Collagen SHG

Indoleamines Collagen SHG

WE FLUORESCE - Nonlinearly

Intrinsic tissue fluorescence and harmonic generation (SHG or THG) are unique to multiphoton excitation, allowing imaging live human and animal without fluorescent dye.

20 µm

Potential for clinical applications.

Intrinsic tissue fluorescence (ITF) and Second Harmonic Generation (SHG)

Sensitivity = 90.4% Specificity = 76.9% MPM Sensitivity = 73% Specificity = 43%

“Multiphoton microscopy in the evaluation of human bladder biopsies” by S. Mukherjee et al. Archives of Pathology and Laboratory Medicine, 2012

Routine cystoscopy

Human bladder

Multiphoton imaging H&E stained histology ≈

Proven in Multiphoton Microscopy (~ 2000 microscopes and 1000 papers/year)

A lab-built multiphoton microscope Titanium-Sapphire femtosecond lasers

XY scanner

Clinical Endoscopy

microscope

(2007 – present)

3 mm flexible endoscope

1 mm needle endoscope

optical zoom endoscope

Opt. Lett. 35, 2735-2737, 2010 PNAS 108, 17598-17603, 2011 Biomed. Opt. Exp. 3, 1077–1085, 2012 Opt. Lett., 37, 1349-1351, 2012 Opt. Lett., 37, 881-883, 2012 J. Biomed. Opt. 17, 040505 (2012) Patents pending

Developed Endoscope Prototypes

1 mm needle lens

Multiphoton endoscopy vs microscopy

Mouse lung autofluorescence

Mouse colon autofluorescence

“Compact and flexible raster scanning multiphoton endoscope capable of imaging unstained tissue”, PNAS 2011, 108, 17598-17603.

Movie: Live animal imaging

Biomed. Opt. Exp. 3, 1077–1085, 2012 J. Biomed. Opt. 17, 040505 (2012)

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Indications and Value Propositions Nerve-sparing prostate resection – avoid nerves

Better patient outcomes Quickest path to market for Newco

Tumor margin evaluation during resection Better patient outcomes Save surgeon/OR time compared to frozen sections

Optical biopsy, in indications requiring surveillance and defensive or aggressive biopsies (e.g. bladder cancer) Patients avoid unnecessary pain/morbidity and delay Insurers avoid unnecessary lab testing

first-to-market

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In a test dataset of recent biopsy submissions from cystoscopic procedures to surgical pathology over a 2-month period, our collaborators at Weill Medical College found:

• 70% of the cystoscopic biopsies were benign

>4 million cystoscopies are performed every year in Europe and North America

Assuming - a rate of benign biopsies of 70%, and - an average of 1 biopsy/cystoscopy procedure

• ~2.8 million benign biopsies each year

• cost of $1.12 billion/year (assuming an average billing rate of ~$400/biopsy).

Bladder cancer: Current clinical problem

wasted time for surgeon + patient morbidity + possibility of complications

Competitive Technologies • Fluorescence Endoscopy

– External fluorophore must be applied – Identical to simple light endoscopy – Not diagnostic, not the cellular level

• Optical Coherence Tomography

– Recognizes optical patterns (reflection/scattering) – Not chemically specific – Not comparable to “gold standard” histology

• Confocal Endoscopy

– External fluorophore must be applied in general – Poor tissue penetration

Other Medical Imaging Technologies

• MRI • CT and X-ray • Ultrasound

• All provide minimally-invasive imaging with deep penetration but low spatial resolution.

• Synergistic, and can be combined with in vivo multiphoton endoscopy. – e.g., ultrasound guided multiphoton endoscope

Envisioned product: multiphoton endoscopes Combine with existing endoscope systems

Olympus CV-160 Video colonoscopy System

• Our flexible endoscope is small enough to pass through the working channels. • Leveraging the existing platform for white-light/narrow-band illumination, wide-field imaging, liquid flushing, and mechanical manipulation

working channel

working channel7.5 fr

21 fr

15 fr

Richards and Wolf cystoscope

Envisioned product: multiphoton laparoscopes Combine with existing laparoscopy

• Laparoscopic imaging • Robotic manipulation • Stereoscopic imaging • Liquid flushing

Da VinciTM system

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Multiphoton surgical endomicroscope • Real-time tissue assessment • Contrast-free • Improve outcomes

• margin assessment • avoid sensitive structures (e.g., nerves) • minimize unnecessary biopsies

Chris Xu: cx10@cornell.edu

Acknowledgments PhD students: David Rivera David Huland Post-docs: Dimitre Ouzounov Chris Brown Ina Pavlova (Former) Minghan Chen (Former)

Cornell Collaborators: Watt W. Webb Robert Weiss Teresa Southard Wendy O. Williams Weill Cornell Medical College: Sushmita Mukherjee (PhD) Doug Scherr (MD) Ashutosh K. Tewari (MD)

Supported by NIH/NCI and NIH/NIBIB