Early clinical experience with the ACTA scanner

Bronchoscopic Diagnostic Procedures Available to the Pulmonologist

In the diagnosis of lung cancer, pulmonologists have several tools at their disposal. From the tried and true convex probe endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration to robotic bronchoscopy for peripheral lesions and new technology to unblind the biopsy tools, this article elucidates and expounds on the tools currently available and being developed for lung cancer diagnosis.

The Beatles, the Nobel Prize, and CT scanning of the chest

Chest CT scanning has come a long way since 1975. Anatomic images are now superb and functional imaging is in its early stages.

Imaging of the pancreas with computed tomography

In this paper we present our experience with computerized tomographic imaging of the pancreas, both in normal and abnormal conditions. Eighty patients were studied for evaluation of pancreatic disease. A further 50 patients, all with a normal pancreas, were studied for abnormalities of other abdominal organs and served as the control group. Helpful signs in establishing the diagnosis of carcinoma of the pancreas were mass effect within the pancreas, alteration of organ contour and obliteration of retroperitoneal fat planes. We found that differentiation from pancreatitis or retroperitoneal lymphadenopathy may at times be difficult. Our results showed that in 22 out of 23 patients with proven normal pancreas, the pancreas size on the CT display was within the adopted normal range. In 30 patients with proven carcinoma of the pancreas, a pancreatic mass was seen in 24 (83%). Computerized tomography is clearly a valuable method for viewing both normal pancreatic anatomy and anatomical variations and pathologies.

Technical aspects of CT scanning

The advent of computed tomography (CT) has initiated a technological revolution which continues to the present time. A brief review of basic principles of CT scanning is presented, and the evolution of modern CT scanner systems is traced. Some early indications of future trends are also presented.

Computed tomography of gas-filled bladder: method of staging bladder neoplasms

Current methods of staging bladder carcinoma have many disadvantages. A new method of staging bladder tumors employing computed tomography (CT) of the gas-filled bladder is presented. Representative cases are demonstrated. Direct visualization of the extent of the tumor and adjacent soft tissue structures is possible. CT scanning of the gas-filled bladder is a promising new method for staging bladder tumors and following their response to therapy.

Computerised axial tomography for diagnosis of pancreatic cancer

Computerised axial tomography demonstrated the presence of a mass lesion in the pancreas in 9 (64%) of 14 patients with histologically confirmed pancreatic cancer. Since this was a retrospective analysis, the percentage of false positive and negative results using this technique is not as yet known. The technique appears accurate in detecting abnormal pancreatic masses of 10 cm in diameter or more, however, for masses less than 10 cm in diameter the yield at present is only 33%. With further technical refinement to increase resolution, the automatic computerised transverse axial scan should prove to be an invaluable procedure for the detection of pancreatic carcinoma, in designing radiation therapy ports, and in providing objective information regarding response of therapy and progression of disease.

RETRACTED: Differing attenuation coefficients of normal and infarcted myocardium

There are significant differences in attenuation coefficients between normal and infarcted myocardium measurable with a computerized transaxial tomographic scanner. Additionally, iodinated contrast material administered prior to killing the tests animals resulted in excellent visualization of the blood-myocardial interface at a time when standard radiographs detected no differences between the ventricular cavity and the myocardial wall. These natural and induced changes in attenuation coefficients offer a new approach to evaluating and understanding the processes of tissue injury and death. Their clinical relevance lies in application to the twin problems of myocardial infarction and the structure and function of the cardiac wall.

Ultrasonic and radionuclide scanning in pancreatic disease

Ultrasonic examination of the pancreas is rendered difficult by the echogenic characteristics of the organ, by its depth, by the overlying gas, and by bony structures and anatomic variations. The reintroduction of gray-scale imaging promises to simplify the technique and expand its usefulness. The 75Se-/-selenomethionine scan is a reliable test when performed after effective pancreatic stimulation with a scintillation camera that permits the angulation required to separate pancreas from liver. Gallium-67-citrate may be important for both mapping inflammatory processes and imaging some tumors. Retrograde pancreatography has developed into a rather reliable and sensitive method of visualizing pancreatic duct abnormalities. Angiography remains the most reliable technique for finding small lesions, while computerized axial tomography appears a promising modality in the near future. In acute pancreatitis, gallium scanning may find a place alongside plain films, GI series, and echography. Chronic pancreatitis appears best studied by pancreatography, possibly with selenomethionine scanning as a function study and echography to find associated mass lesions. Pseudocysts are most easily located by ultrasound examination. Screening for pancreatic carcinoma is done most effectively with selenomethionine scanning when the index of suspicion is low and with pancreatography or arteriography when it is high. Echography is useful for localization for aspiration biopsy and for sequential evaluation of therapeutic response. Islet-cell tumors are best found by angiographic studies.