Introduction of Endoscopic Ultrasonography (EUS)

Dr. Yuk Tong LEEMBChB, MD(CUHK), FRCP (Edin), FRCP(Lond), FHKCP, FHKAMSpecialist in Gastroenterology and Hepatology

Endoscopic Ultrasonography (EUS)

ª Combines both endoscopic and ultrasonic examination

in one

ª High frequency USG transducer used

ª Close proximity to the GIT and surrounding organs

ª Highly accurate in diagnosing both mural and

extramural structural abnormality

ª EUS guided fine needle aspiration and intervention

Electronic radial echoendoscope

GF-UE260

• Color and Power Doppler study

• Contrast study

Linear echoendoscope –Fine needle aspiration to obtain cytology

Miniature probes

UM2R / 3RUM-G20-29R

UM-G20-26R

Clinical practiceª Endoscopic diagnostician (Upper GI, pancreatobiliary)

ª Electronic radial EUSª Olympus (forward oblique)

ª Fujinon / Pentax (forward end viewing)

ª Miniprobe ª 12MHz (most commonly used)

ª 20MHz, IDUS – highly specialized.

ª Practice related to oncology centre – linear EUS for both diagnosis and staging, FNA and tumour therapy.

ª Pulmonary physician and cardiothoracic surgery – EBUS + FNA

ª Colorectal surgery – miniprobe, rectal probe

Diagnostician

Pulmonary

Oncology

Colorectal

The “ECHO-ENDOSCOPIST”

Diagnostic EUSMural and extramural lesions•Diagnosis of cyst, GIST, submucosal mass (assessment before mucosectomy, ESD) •Thickened gastric fold •Determine cause of GI tract stricture (anastomotic, reflux, extrinsic compression, achalasia)

Staging of GI tract malignancies•Oesophageal and gastric cancer•Gastric lymphoma / MALToma •Detection of malignant ascites and peritoneal metastases•Restaging after chemotherapy

Staging of non-GI tract malignancies•Non-small cell lung cancer•Mediastinal tumour / lymph node•(Gynaecological cancer)

Biliary diseases•Common bile duct stones, sludge and cancer•GB tumour, stone, polyps and other pathologies

New methodsEUS harmonic contrast studyEUS elastography

Pancreatic diseases•Pancreatic and ampullary cancer•Endocrine tumour, cystic tumour , IPMT•Acute, chronic and idiopathic pancreatitis•Assessment of pseudocyst (before drainage)

Colorectal diseases•Colorectal cancer and large polyps•Colorectal submucosal mass and carcinoid•IBD (CD, UC)•Fistula-in-ano, incontinence, pelvic floor dysfunction•Early detection of rectal tumour recurrence•Pelvic diseases (abscess, prostate, endometriosis, etc)

Portal hypertension•Diagnosis of gastroesophageal varices and collaterals•Monitoring drug and endoscopic therapy•Haemodynamic study

Dyspepsia and unexplained abdominal pain

Indications for EUS (EBUS) - FNA and trucut biopsyEUS-FNA of tumours•GIT stromal tumour (GIST, leiomyoma, linitus plastica, etc)•Lung tumour and metastases•Liver metastases•Adrenal metastases

Pancreatic lesion•Solid pancreatic mass•Cystic lesion - FNA for fluid analysis, EUS guided brush cytology, EUS guided direct intra-cystic biopsy•EUS tattoo of small neuroendocrine tumour

EUS-FNA of lymph node in GIT cancer•Peri-esophageal, celiac axis lymph node•Peri-gastric •Peri-pancreatic•Peri-rectal

EUS (EBUS) - FNA of mediastinal lymph node for staging of NSCLC

EUS (EBUS) - FNA of other mediastinal lymph nodes and masses•Metastases•Lymphoma•TB, Sarcoidosis, Histoplasmosis, etc

EUS-FNA of other lesions•Ascites•Pleural effusion•Pericardial effusion

Therapeutic and Interventional EUS (investigational)EUS-guided injection therapy•Celiac plexus neurolysis•Broad plexus neurolysis (around SMA) •(Hypogastric plexus neurolysis)•Botox injection for achalasia•Sclerotherapy of OV and GV•Lavage (alcohol, paclitaxel) of pancreatic cystic tumour

EUS-guided tumour therapy•Iodine 125 seeds placement for brachytherapies •Fiducial placement for stereotactic radiation•(Tumour ablation – thermal probe, cryo probe, photodynamic probe, laser probe, radiofrequency (High intensity focused ultrasound, HIFU) )

(EUS-guided tumour injection therapy) •Injection of cytoimplant, gene therapy, chemotherapeutic agents, immune modulators•Alcohol ablation of liver metastases, small pancreatic neuroendocrine tumour, etc.

EUS-guided abscess drainage•Liver abscess•Sub-phrenic abscess •Peri-rectal abscess

EUS-guided ERCP•Pancreatic ductal cannulation•CBD rendezvous cannulation

EUS-guided drainage•Pancreatic pseudocyst drainage•Pancreatico-gastrostomy (EPG)•Choledocho-duodenostomy•Cholecysto-duodenostomy•Hepatico-gastrostomy

EUS guide vascular therapy•Cyanoacrylate injection for bleeding varices and aneurysm•Endocoil placement for varices and aneurysm•(TIPS placement)

(EUS guided anastomotic surgery)•Gastro-jejunostomy•Choledocho-duodenostomy

EUS-guided angiography

EUS guided needle confocal endomicroscopy