Ultrasonography of internal organs using an ultrasound transducer sometimes mounted on a fiberoptic endoscope. In endosonography the transducer converts electronic signals into acoustic pulses or continuous waves and acts also as a receiver to detect reflected pulses from within the organ. An audiovisual-electronic interface converts the detected or processed echo signals, which pass through the electronics of the instrument, into a form that the technologist can evaluate. The procedure should not be confused with ENDOSCOPY which employs a special instrument called an endoscope. The "endo-" of endosonography refers to the examination of tissue within hollow organs, with reference to the usual ultrasonography procedure which is performed externally or transcutaneously.

Conducting a fine needle biopsy with the aid of ENDOSCOPIC ULTRASONOGRAPHY.

Using fine needles (finer than 22-gauge) to remove tissue or fluid specimens from the living body for examination in the pathology laboratory and for disease diagnosis.

Removal and examination of tissue obtained through a transdermal needle inserted into the specific region, organ, or tissue being analyzed.

The use of ultrasound to guide minimally invasive surgical procedures such as needle ASPIRATION BIOPSY; DRAINAGE; etc. Its widest application is intravascular ultrasound imaging but it is useful also in urology and intra-abdominal conditions.

Tumors or cancer of the PANCREAS. Depending on the types of ISLET CELLS present in the tumors, various hormones can be secreted: GLUCAGON from PANCREATIC ALPHA CELLS; INSULIN from PANCREATIC BETA CELLS; and SOMATOSTATIN from the SOMATOSTATIN-SECRETING CELLS. Most are malignant except the insulin-producing tumors (INSULINOMA).

Sharp instruments used for puncturing or suturing.

A small circumscribed mass in the THYROID GLAND that can be of neoplastic growth or non-neoplastic abnormality. It lacks a well-defined capsule or glandular architecture. Thyroid nodules are often benign but can be malignant. The growth of nodules can lead to a multinodular goiter (GOITER, NODULAR).

Pathological processes of the PANCREAS.

A membrane in the midline of the THORAX of mammals. It separates the lungs between the STERNUM in front and the VERTEBRAL COLUMN behind. It also surrounds the HEART, TRACHEA, ESOPHAGUS, THYMUS, and LYMPH NODES.

A true cyst of the PANCREAS, distinguished from the much more common PANCREATIC PSEUDOCYST by possessing a lining of mucous EPITHELIUM. Pancreatic cysts are categorized as congenital, retention, neoplastic, parasitic, enterogenous, or dermoid. Congenital cysts occur more frequently as solitary cysts but may be multiple. Retention cysts are gross enlargements of PANCREATIC DUCTS secondary to ductal obstruction. (From Bockus Gastroenterology, 4th ed, p4145)

Infection of the lymph nodes by tuberculosis. Tuberculous infection of the cervical lymph nodes is scrofula.

Diagnosis of the type and, when feasible, the cause of a pathologic process by means of microscopic study of cells in an exudate or other form of body fluid. (Stedman, 26th ed)

Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)

Tumors or cancer of the THYROID GLAND.

INFLAMMATION of the PANCREAS that is characterized by recurring or persistent ABDOMINAL PAIN with or without STEATORRHEA or DIABETES MELLITUS. It is characterized by the irregular destruction of the pancreatic parenchyma which may be focal, segmental, or diffuse.

The removal of secretions, gas or fluid from hollow or tubular organs or cavities by means of a tube and a device that acts on negative pressure.

Endoscopic examination, therapy or surgery of the bronchi.

Tumors or cancer of the MEDIASTINUM.

A nodular organ in the ABDOMEN that contains a mixture of ENDOCRINE GLANDS and EXOCRINE GLANDS. The small endocrine portion consists of the ISLETS OF LANGERHANS secreting a number of hormones into the blood stream. The large exocrine portion (EXOCRINE PANCREAS) is a compound acinar gland that secretes several digestive enzymes into the pancreatic ductal system that empties into the DUODENUM.

A type of lung inflammation resulting from the aspiration of food, liquid, or gastric contents into the upper RESPIRATORY TRACT.

Conducting a biopsy procedure with the aid of a MEDICAL IMAGING modality.

Inhaling liquid or solids, such as stomach contents, into the RESPIRATORY TRACT. When this causes severe lung damage, it is called ASPIRATION PNEUMONIA.

The local implantation of tumor cells by contamination of instruments and surgical equipment during and after surgical resection, resulting in local growth of the cells and tumor formation.

Diseases of LYMPH; LYMPH NODES; or LYMPHATIC VESSELS.

Tomography using x-ray transmission and a computer algorithm to reconstruct the image.

The visualization of deep structures of the body by recording the reflections or echoes of ultrasonic pulses directed into the tissues. Use of ultrasound for imaging or diagnostic purposes employs frequencies ranging from 1.6 to 10 megahertz.

Liquid material found in epithelial-lined closed cavities or sacs.

A highly vascularized endocrine gland consisting of two lobes joined by a thin band of tissue with one lobe on each side of the TRACHEA. It secretes THYROID HORMONES from the follicular cells and CALCITONIN from the parafollicular cells thereby regulating METABOLISM and CALCIUM level in blood, respectively.

Pathological processes of the BREAST.

Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.

Pathological processes involving the THYROID GLAND.

They are oval or bean shaped bodies (1 - 30 mm in diameter) located along the lymphatic system.

Chemical agents injected into blood vessels and lymphatic sinuses to shrink or cause localized THROMBOSIS; FIBROSIS, and obliteration of the vessels. This treatment is applied in a number of conditions such as VARICOSE VEINS; HEMORRHOIDS; GASTRIC VARICES; ESOPHAGEAL VARICES; PEPTIC ULCER HEMORRHAGE.

The use of needles usually larger than 14-gauge to remove tissue samples large enough to retain cellular architecture for pathology examination.

Negative test results in subjects who possess the attribute for which the test is conducted. The labeling of diseased persons as healthy when screening in the detection of disease. (Last, A Dictionary of Epidemiology, 2d ed)

Methods used to study CELLS.

In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.

Non-invasive diagnostic technique for visualizing the PANCREATIC DUCTS and BILE DUCTS without the use of injected CONTRAST MEDIA or x-ray. MRI scans provide excellent sensitivity for duct dilatation, biliary stricture, and intraductal abnormalities.

Disorders of the mediastinum, general or unspecified.