Slide 176 Depth of Penetration: EUS compared Endoscopic ultrasound is designed to be able to penetrate the wall of the GI tract and provide high quality imaging. Other newer imaging modalities can also provide highly detailed images of the GI mucosa, but are not able to provide images demonstrating the entire wall structure. Endoscopic confocal microscopy provides a 1000x magnification of the mucosa with histologic quality. Optical coherence tomography is an experimental imaging device commonly employed in coronary angiography and adapted for imaging of Barrett’s esophagus.
Slide 215 EUS Wall Imaging and Correlates with Histology EUS imaging (probe endosonography) of GI tract wall demonstrates alternating layers of hyper and hypoechoic rings. Generally, the hypoechoic rings correspond to muscle layers because the high water content of muscle absorbs the ultrasound waves resulting in a dark (hypoechoic) structure.
Slide 179 Mechanical Radial Array Imaging The first generation echoendoscopes were mechanical radial echoendoscopes that provided cross sectional images of the GI tract (the transducer is located in the center of the generated EUS images). Although the quality of the images was excellent, the mechanically-rotating transducer was a source of frequent repairs. Doppler imaging and fine needle aspiration are not possible with mechanically rotating radial echoendoscopes.
Slide 180 Electronic Transverse Array Imaging: 270° ‘Radial’ Echoendoscope The second generation radial echoendoscope features an electronic transducer and is free of moving parts. Color Doppler imaging is provided by the instrument. This is an example of a 270 degree transducer and an end-viewing echoendoscope. The transducer is wrapped 270 degrees around the shaft of the endoscope and provides cross sectional image with a missing 90 degree wedge. The instrument channel is located in the center of echoendoscope and can be used for endoscopic biopsies.
Slide 181 Electronic Radial Array Imaging: 360° End-Viewing Radial Echoendoscope The newest type of electronic radial echoendoscope provides a true cross-sectional (360 degrees) image with color Doppler capability. The transducer has been placed on the shaft of the endoscope in a 360 degree wrap. The endoscopic viewing is from the tip and the ultrasound transducer is located just above the transducer. The high resolution imaging and color Doppler feature provide cross sectional images featuring normal vascular structures.
Slide 184 Curved Linear Array Diagnostic Echoendoscope In contrast to radial instruments, all linear array echoendoscopes contain an electronic transducer. The use of an electronic ultrasound transducer has many advantages over mechanical transducers, including the lack of fragile rotating drives. Color Doppler imaging is a feature on all these instruments. In linear instruments, a needle channel is located such that an aspiration needle can be placed with ultrasound guidance. Fine needle aspiration is an important feature that differentiates between radial and linear array instruments. An elevator control allows for fine adjustments in the trajectory of the needle as it exits the instrument channel. A balloon is used to provide fluid-coupling between the transducer and the target lesion.
Slide 185 Therapeutic Linear Echoendoscope Linear echoendoscopes may have a diagnostic or a therapeutic instrument channel. Therapeutic echoendoscopes enable the endoscopist to place stents through a large instrument channel into pseudocysts, abscesses, or focal fluid collections. An elevator in the instrument channel provides precise control of the needle or stent.
Slide 186 EUS-Guided FNA EUS-guided fine needle aspiration is performed with linear echoendoscopes and Doppler imaging. The aspiration needle is placed into lesions in the GI tract wall or organs adjacent to the GI tract. The aspirated tissue is stained and examined with cytologic techniques.
Slide 192 EUS Accessories Small gauge needles are the most commonly used accessory with EUS. Recently, other accessories have introduced. A brush has been designed to supplement the acquisition of tissue during aspiration. A cystotome is used to gain access to a pseudocyst through the GI tract wall. A therapeutic injection needle is designed to inject neurolytic agents into the celiac ganglia.
Slide 200 Wilson-Cook Quick-Core Needle In contrast to aspiration needles which provide cytologic material, a trucut needle provides a core of tissue for histology. The Quick-core needle is a 19 gauge spring-loaded needle device that can be used to provide a histologic core of tissue from subepithelial masses and pancreatic lesions. It is difficult to deploy the needle from a flexed echoendoscope and therefore the most common targets are located in the pancreatic body and subepithelial masses in the proximal stomach.
Slide 189 High Frequency Probe Endosonography High frequency probe endosonography offers some unique imaging capabilities and supplements the imaging provided by standard EUS equipment. Radial probes use high ultrasound frequency and therefore provide high resolution images of mucosa and submucosal lesions. However, there is no Doppler capability because the probes use radial mechanical transducers. Since water-filled balloons are not used, water is usually provided in the gut lumen, as a coupling agent.
Slide 239 Gastric Imaging Station II: Posterior: Celiac Trunk The celiac trunk is a major landmark along the posterior aspect of the stomach, just below the gastroesophageal junction. It is best found by advancing the endosonoscope along the aorta until the first branch off the aorta is seen. The area between the celiac, aorta, and the posterior wall of the stomach is a common place for malignant adenopathy. It should be examined in all patients with a malignancy. Just below the celiac trunk is the origin of the SMA.
Slide 303 Celiac Neurolysis Celiac neurolysis is performed from the cardia of the stomach, with the EUS transducer oriented posteriorly towards the aorta. Injections of a long-acting anesthetic (bupivacaine) provide transient nerve blockade and ethanol injections result in neurolysis and longterm pain relief. In some patients, a careful exam will reveal the celiac ganglia structure, a good target for injection neurolysis.
Kadife Kaya 28.12.2007
Slide 329 Insulinoma Insulinomas are pancreatic neuroendocrine tumors (NET) that secrete insulin and cause symptoms related to episodes of hypoglycemia. The EUS appearance of insulinomas is identical to other pancreatic NET. The solitary nature of the lesion makes the EUS evaluation relatively easy, but the examination should include the entire pancreas. FNA provides cytologic material that is often diagnostic of a NET.
Sinaptofizin +, kromogranin+, CK7-, CK19-. Hücre bloğunda NET(pankreas adacık tümörü ile uyumlu)
Slide 326 Gastrinoma When pancreatic neuroendocrine tumors (NET) secrete a hormone that results in symptoms, the lesion is named for the hormone the tumor secretes. Gastrinomas have an appearance identical to other pancreatic NET, but are located in the gastrinoma triangle. Although gastrinomas are readily identified by EUS, the multifocality of the lesion makes it difficult to determine which is the primary.
Slide 327 Gastrinoma Triangle Since 90% of gastrinomas are located in the boundries of the duodenum, head of pancreas, and the gallbladder, the EUS examination should be from the duodenum. The EUS evaluation should also include a detailed examination of the duodenal wall and periduodenal space.
Mesankimal m lerin yarıs GIST. Diğer yarısı ise lipom, leiomyom veya LMS schwannom
Slide 241 Imaging of the Gastric Wall: Correlation Between Ultrasound and Histology The five major layers of the gastric wall are easily seen in the water filled stomach. The alternating hypo and hyperechoic layers correspond roughly with the histologic layers.
Slide 258 Benign Gastric Stromal Cell Tumors (GIST) Benign GISTs often appear with a small central umbilication or a deeper ulceration. The ultrasound appearance is variable but the masses are usually hypoechoic, homogenous and well demarcated, originating from the 4th layer.
Slide 259 Features of Malignant GIST Malignant GISTs often have areas of marked heterogeneity, cystic spaces, or a diameter of greater than 3cm.
Niyazi Uluçay, 941486,14.11.2007
Bez oluşturmaya eğilim var, nukleositoplazmik oran artmış, kanser hücreleri grup oluşturma eğiliminde. Raporda: Malignite + yaymalar, sitomorfolojik bulgular immunhistokimya ile birleştirildiğinde az diff adeno ca olarak değerlendirildi. Kromogranin nonspesifik, sinaptofizin (-), TTF (-), CEA: az sayıda hücrede immünekspresyon izlendi
Slide 269 Pancreatic-Biliary Imaging Station II The second imaging station is proximal to ampulla and just distal to the bulb. Along the superior aspect of the duodenum, the gallbladder is seen as a large round smooth structure filled with fluid. The head of the pancreas can be seen in detail and sometimes one can appreciate that the ventral and dorsal portions of the pancreas will have slightly different echogenicity. Behind the head of the pancreas lies the portal vein as it courses towards the liver. The bile duct usually lies between the duodenal wall and the portal vein.
Pank içinde CBD ve yukarda sistik kanal
Slide 276 Gallbladder Sludge Here is an example of gallbladder sludge, hyperechoic material filling the gallbladder lumen.
Slide 288 Pancreatic Adenocarcinoma of the Body Pancreatic adenocarcinoma in the body of the pancreas appears as a focal hypoechoic mass infiltrating through the gland and usually obstructing the main pancreatic duct. Malignancies in the body of the pancreas often invade the splenic vein that courses along the posterior aspect of the pancreas.
Slide 290 Pancreatic Mass FNA Fine needle aspiration (FNA) of a pancreatic mass is performed from the stomach or the duodenum using a linear endosonoscope. Color Doppler helps direct the passage of the needle around vascular structures. Aspiration of tissue from the mass is examined cytologically for evidence of malignancy.
Slide 293 Locally Invasive Pancreatic Cancer Early pancreatic malignancies, stage T1 or T2, are contained within the pancreatic parenchyma. If there is evidence of portal vein involvement, the malignancy is staged T4, often interpreted as indicating unresectability. The degree of involvement of the portal vein may be described in terms of the length of contact of the portal vein wall by the mass.
Slide 295 Portal Vein Thrombosis Portal vein thrombosis can be readily detected with EUS as a mobile filling defect within the portal vein lumen or a fixed obstructing mass. One of the common causes of portal vein thrombosis is pancreatic cancer. A clot may arise in the portal vein as a result of the hypercoaguable state or direct invasion of the vein by the malignancy.
Slide 216 TNM Staging of GI Tumors The Tumor Nodal Metastasis (TNM) staging classification is commonly used for the staging of GI tumors. EUS provides detail imaging of the tumor in relationship to the layers of the GI tract. T1 and T2 tumors are considered intra-esophageal and an early stage, whereas T3 and T4 tumors are considered advanced and predict a poor prognosis. Malignant lymph nodes (N1) are commonly associated with advanced malignancies.
Slide 188 Linear Imaging: Esophageal Mass Example Linear echoendosonography can also provide images of esophageal cancer. In linear array images, only one wall of the esophagus is seen and the hypoechoic linear structure (muscularis propria) is parallel to the axis of the scope. Esophageal cancer is staged by determining whether the mass (heterogenous hypoechoic tissue) has invaded through the wall or the muscularis propria (see arrow). In advanced esophageal cancer, the hypoechoic mass has invaded through the muscularis propria and into the bright white fat in the mediastinum. The accuracy of esophageal cancer staging with linear and radial endosonography is similar.
Slide 250 Stage T4 Gastric Cancer Stage 4 gastric cancer is documented with EUS by demonstrating the invasion of organs adjacent to the stomach. In this example a 270 degree radial echoendoscope has demonstrated that the gastric cancer has invaded adjacent small bowel (note the presence of air in the bowel: see arrow).
Slide 208 Esophageal Wall Imaging: Benign Esophageal Duplication Cyst Duplication cysts are often located along the esophagus and are usually discovered incidentally on a CT scan. The lesions are readily seen as sharply demarcated anechoic structures (1-5cm in diameter) in close proximity to the esophageal wall. The cysts are filled with a viscous acellular translucent fluid. Although the cysts can be easily aspirated, there are usually no diagnostic findings on cytology and there is a risk of contamination of the cyst with GI flora. Antibiotics should be administered to the patient, if the cyst is aspirated. The color Doppler window demonstrates that there is no flow within the cyst.
Slide 207 Esophageal Wall Imaging: Intramural Wall Lesion This small, solid lesion of the esophageal wall demonstrates a typical intra-mural mass (black arrows). Endoscopically, the lesion is apparent as a mass covered by normal mucosa. The tissue within the mass is hypoechoic and homogenous. There are multiple calcifications (bright white foci) within the mass, highly suggestive of a benign leiomyoma.
Slide 308 EUS Appearance of Pseudocyst Pancreatic pseudocysts have a variety of presentations and appearances on EUS. Necrotic tissue may collect in the dependent portion of the fluid collection and represents debris. In advanced pseudocysts, the wall become progressively thicker, resulting in a greater degree of difficulty in terms of needle placement or stenting.
Slide 309 Mucinous Cyst Neoplasm Mucinous cystic neoplasms are most commonly seen in the tail of the pancreas and are associated with high degree of gender specificity (female predominance). The secretory epithelium secretes large quantities of mucinous fluid with a high viscosity. The cyst fluid CEA is often elevated, reflecting the secretory nature of the epithelium. Ductal communication is rare and therefore the cyst fluid amylase concentration is usually low.
Slide 316 Serous Cystadenoma Serous cystadenomas are benign cystic lesions that are often microcystic in appearance on CT-MRI imaging and EUS. The cystic compartments are lined by a small cuboidal cell that is stained with PAS, demonstrating evidence of intracellular glycogen. The cyst fluid fluid contains low concentrations of amylase and CEA. FNA cytology is usually not diagnostic because of the small number of cells present in the aspirate. The vascularity of the cyst may result in contamination of the cytologic specimen by blood.
Slide 318 Macrocystic Serous Cystadenoma The EUS appearance of serous cystadenomas varies a great deal in terms of the number and size of the cyst compartments. When the compartments become larger and discrete, the lesion is described as macrocystic and simulates a mucinous lesion.
Slide 319 IPMN Intraductal papillary mucinous neoplasm (IPMN) is the most common malignancy of the pancreas. The lesions are characterized by a papillary mucinous epithelium that grows along ducts resulting in dilated ducts and cysts. Side branch lesions are rarely malignant whereas main duct disease is frequently malignant at the time of presentation. The lesions appear as cystic areas in the pancreas on MRCP (T2 bright) and as low attenuation lesions on CT scan.
Slide 320 IPMN: Main Duct Disease Main duct IPMN represents a papillary mucinous tumor growing along the epithelial wall of the main pancreatic duct. As a result of the tumor growth, the duct dilates and contains a large amount of mucoid material secreted by the tumor. The mucinous material may appear within the ampulla or as a filling defect within a pancreatogram.
Slide 322 Malignant IPMN As IPMN evolves into a malignancy, the wall of the duct or cyst becomes thickened and nodular. Fine needle aspiration should target mural nodules, masses, and thick walls.
Slide 271 EUS Findings of Chronic Pancreatitis There are many EUS findings in chronic pancreatitis. Focal calcifications appear as bright hyperechoic shadowing foci within the parenchyma and are nearly diagnostic of chronic pancreatitis. Floating stones in a dilated main pancreatic duct are commonly seen and are nearly as diagnostic as calcifications.
Slide 273 EUS Findings of Chronic Pancreatitis The minor EUS criteria for chronic pancreatitis consist of parenchymal changes (lobularity, atrophy, and hyperechoic foci) and duct dilation.
Slide 281 Cholangiocarcinoma EUS imaging of cholangiocarcinomas is performed from the duodenum. The malignancy appears as a focal irregular hypoechoic mass lesion surrounding the bile duct. The mass should correspond anatomically with the location of the stricture seen on cholangiography. Ductal edema as a result of recent stent placement is associated with overstaging of cholangiocarcinoma.
Slide 323 Pancreatic Neuroendocrine Tumor Pancreatic neuroendocrine tumors appear as a focal round isoechoic mass in the pancreas. The EUS appearance readily differentiates them from adenocarcinoma, but metastases to the pancreas may have a similar appearance.
Slide 336 Imaging Characteristics of Autoimmune Pancreatitis The lympho-cytoplasmic infiltration of the pancreatic parenchyma produces a diffuse enlargement of the gland or a focal mass. Characteristically the main pancreatic duct is narrowed and irregular. A focal mass may simulate pancreatic malignancy in its imaging characteristics and biliary obstruction. Fine needle aspiration cytology often yields non-diagnostic material at times with evidence of stromal and lymphocytic elements.
Slide 268 Peri-Pancreatic Venous Anatomy: Pancreatic Head Cancer Since the portal vein passes through the posterior aspect of the pancreatic head, tumor staging involves a careful examination of the mass in relation to the vein. In early stages, the tumors invades only the wall of the vein. In more advanced stages, the mass obliterates the entire vein.
Slide 191 EUS Accessories: Balloons Balloons are the most commonly employed accessory for endosonography. Although they are not essential for the performance of EUS exams, the balloons provide a fluid interface between the transducer and the tissue. Most balloons are latex, but a non-latex linear EUS balloon has recently been introduced. Single-opening balloons are used for linear echoendoscopes and double-opening balloons are used for radial echoendoscopes.
Slide 236 Gastric Imaging Station 1: Gastric Wall Gastrointestinal stromal cell tumors are the most common solid intramural lesions in the stomach. On ultrasound they are round, homogenous, and hypoechoic. The lesions usually arise from the 4th layer, the muscularis propria and represent the myogenic cell of origin, the cells of Cajal.
Slide 256 Gastric Stromal Cell Tumors (GIST) Most stromal cell tumors (GISTs) arise from the muscularis propria, the 4th layer of the gastric wall. The masses may straddle the muscularis or form a stalk-like attachment. The attachment to the muscularis is highly suggestive of a stromal cell tumor, but not diagnostic. FNA can provide cytologic evidence of a GIST through the demonstration of spindle cells.
Slide 187 Radial Imaging: Esophageal Mass Example One of the classic EUS images is esophageal cancer and its relationship with the esophageal wall. In images derived from a radial echoendoscope, the esophageal wall (muscularis propria) is seen in cross section as a hypoechoic ring. In the center of the radial EUS image is the transducer (round black space). In advanced esophageal cancers, the mass has invaded beyond the muscularis propria and into the bright white fat of the mediastinum. In mechanical radial echoendoscopes, there are multiple bright rings surrounding the transducer, representing a reverberation artifact.
Slide 243 Thickened Gastric Folds Thick gastric folds are a common indication for an EUS examination. Benign thick gastric folds appear as isoechoic redundant tissue, as seen in this example. Malignant thick folds are usually hypoechoic with obliteration of the wall layers.
ENDOSCOPICULTRASOUNDEUS Cem KALAYCI Marmara University, Istanbul Dept. Of Gastroenterology BAKU, 2008
EUS CPB SM, 36 yo, woman Chronic pancreatitis (idiopathic)+ IDDM ERCP and Biliary endoscopic sphincterotomy Pancreas cannulation failed (x3)
EUS CPB 16.9.06 Roux en Y+ lateral pancreaticojejunostomi (Puestow surgery) due to the intractable pain For 3 months partial relief of pain Subsequently suboptimal pain control with IV pethidin 400 mg/day + doladomon(paracetamol+adamon+ codeine) 1 tab qid
EUS CPB 4.1.2008 EUS CPB No analgesia requirement until1. 5. 2008
GIST-Definition Mesenchymal tumors arising from the GI wall, mesentery, omentum, or retroperitoneum that express c-kit proto- oncogene protein, a cell membrane receptor with tyrosine kinase activity.
Imaging of the Gastric WallCorrelation BetweenUltrasound and Histology
GIST-Incidence <1 % of routine endoscopy Half of the GI submucosal neoplastic masses Surgical series 1% of gastric neoplastic resections Most patients are in 5th or 6th decades 50 % gastric, 25 % small intestine, 10 % colon, 7 % omentum/mesentery, 5 % esophagus Nicki NJ. Curr Opin Gastroenterology 2004;20;482-487
GIST- Clinical Manifestations Usually asymptomatic and incidental endoscopic finding Three major presentations Bleeding 40 % Abdominal mass 40 % Abdominal pain 20 %
Mediastinal mass 54 year old, male, BII 30 years ago Dysphagia, 6-7 kg weight loss/6 months EGD; fragile mass protruding the esophageal lumen at 30. cm, Bx were negative x2 Barrium swallow: Esophageal narrowing Thorax CT:LAPs of 12-16 mm diameter at 7th station in mediastinum PET CT: Malignant activity in esophageal wall, left surrenal and skeleton