New Endoscopic Imaging Techniques

Ross M Bremner MD, PhDDirector, Norton Thoracic Institute

St Joseph’s Hospital and Medical CenterWilliam Pilcher Chair Thoracic Surgery and Transplantation

Professor Surgery, Creighton Medical SchoolPhoenix

AATS 2015

Disclosures

None relevant to this talk

Problem of Barrett’s

1. Barrett’s greatest risk factor for Cancer

2. Most will not develop cancer

3. No way to stratify risk at present with exception of degrees of dysplasia

4. Biopsies VERY unreliable• Histology difficult• Biopsies random!

5. Expense of surveillance very, very high

Biopsies are UNRELIABLE

• While 84% of GI’s will endoscope every 2 years, only 42% do adequate biopsies**– (4 quadrant every 2 cm)

• Barrett’s segment is heterogeneous

• Sampling error can lead to major error

• “1% of 1%”

** Abrams, J: Ther Adv Gastroenterol 2009(2)73

How to improve biopsy “yield”

• Focussed biopsies• Chromoendoscopy• Non-dye chromoendoscopy• OCT/VLE - (Optical Coherence Tomography, Volume Laser

Endoscopy)• Confocal Endomicroscopy

• The Future • Future – cell surface markers (Glycans/Lectin)• Periostin – Ab-dye congugate• Peptides with flourescent labelling

Dye-less chromoendoscopyNBI

High resolution white light Little mucosal or vascular detail

Narro Band Imaging – Blue lightSuperficial layer and vascularityDectect dysplasia

ChromoendoscopyAcetic Acid

20 cc 1.5% Acetic acid(Balsamic 3% also been used)

Disulfide bonds of glycoproteinsDenatures intracellular proteins

Pit PatternsPattern I-II: round pits/circular pattern predicting gastric epithelium;

Pattern III-IV: ridged/villous pattern predicting Barrett's epithelium SCE

Enhances borders.

ChromoendoscopyLugol’s Iodine

10 cc 1.2% Lugol’s Iodine

Stains Glycogen of healthy Squamous cells

Can detect Dysplasia in SCC

Unstained streaks may be useful in NERD

Normal Sq regrowth after ablation

Watch for iodine allergy!

Gastrointest Endosc 2005;62:698-703Endoscopy 2001 Jan; 33(1):75-9

Optical Coherence Tomography(Volume laser endomicroscopy)

Backscattering of light to get cross-sectional images of tissue

Similar to Ultrasound but used light (near infra-red)

Limited to 1-3 mm

SCE – multilayer, homogenous

Barrett’s, glands and crypts, mucin

Optical Coherence Tomography(Volume laser endomicroscopy)

25x higher resolution than EUS

No dye’s or injectables

Excellent software for later analysis

Optical Coherence Tomography(Volume laser endomicroscopy)

Confocal Laser Endomicroscopy

Illumination of tissue with low power laser and detecting fluorescent light reflected from tissue

Intravenous flourescein (vasculature, LP and intracellular spaces)

Confocal endomicroscopyFundic glands, red cells

• “Optical Biopsies”• Real-time cytologic images• Clean mucous with Mucolytic• Relies on flourescence

– Flourescein

Confocal endomicroscopyBarrett’s – No Dysplasia

Goblet cellsNo nuclear atypiaNo stratificationSurface maturation

Concensus Panel - Human Pathology: 2001; 32: 368

Indefinite for Dysplasia

Human Pathology: 2001; 32: 368

Goblet cellsProminent hyperchromasiaGlandular crowdingIncreased mitotic activityMild cytologic atypia

Surface maturation

Low Grade Dysplasia

Human Pathology: 2001; 32: 368

Maintenance of nuclear polarityNo architectural complexity

No Surface maturation

Confocal endomicroscopyBarrett’s – HGD Dysplasia

Nuclear atypiaLoss Nuclear polarityArchitectural complexityBasement membrane in tact

No Surface maturation

Concensus Panel - Human Pathology: 2001; 32: 368

Confocal endomicroscopyIntramucosal Carcinoma

Complex glandular buddingDesmoplasia

Barrett’s cells belowBasement membrane

Concensus Panel - Human Pathology: 2001; 32: 368

Summary• NBI – Enables better imaging of surface

detail and vascular patterns

• Acetic Acid, and Lugols add value

• OCT/VLE – early days, resolution is impressive

• Confocal (CLE)– really helps focus biopsies

Summary• Focussed biopsies and new

imaging technologies will help our diagnostic yield

• Help to stratify those patients with early cancer and those at risk for developing cancer.