Michael Vermess

A prospective study of hepatic imaging in the detection of metastatic disease.

: This prospective study of 80 patients compared the results of liver scintiscan, ultrasound, and CT scan to the objective findings recorded at laparotomy. Analysis of these data revealed no significant differences in sensitivity, specificity, or accuracy among these three imaging procedures, although a trend toward increased accuracy of the CT scan was noted. In a composite analysis, the accuracy was not improved by combining two or all three of these examinations. A lesion by lesion analysis revealed the inability of any of the three currently used techniques to accurately detect lesions less than 3 cm in diameter.

A prospective analysis of laboratory tests and imaging studies to detect hepatic lesions.

A prospective study of the ability of laboratory tests and liver imaging tests to detect hepatic metastases was performed. Eighty patients at risk for hepatic metastases but without clinical evidence of disease were tested with 13 laboratory tests and three liver imaging tests. No single laboratory test had greater than 65% accuracy in the detection of hepatic lesions. No combination of the laboratory tests increased this accuracy. If the laboratory tests were used with one of the liver imaging tests, the accuracy was improved in some combinations to 76%. The CEA assay when analyzed in patients with colorectal primaries had an accuracy of 79%. The results show that the laboratory tests alone are not sufficiently accurate to detect liver metastases. Additional accuracy can be obtained by the combined use of a single liver imaging test and selected laboratory tests. Use of all the liver imaging tests and laboratory tests lowers the accuracy and increases the expense and thus is unnecessary.

Rate of growth of intraabdominal metastases from colorectal cancer

Monitoring the progression or regression of intraabdominal metastatic disease is required for knowledgeable management of chemotherapeutic regimens designed to treat metastases. Computerized tomography (CT) and CT with EOE‐13, a liver contrast agent, allowed precise measurement of metastatic disease. The tumor doubling time of colorectal metastases in four patients was determined from serial CT scans of individual patients. Tumor doubling times of untreated patients varied from 50 to 95 days, and were in the same range for hepatic, lymph node, or intraperitoneal metastatic disease. These data may indicate that metastatic disease of colorectal cancer progresses at a faster rate in the peritoneal cavity than is reported for colorectal cancer metastatic to the lungs. The response to chemotherapy or progression of disease was also determined in treated patients. High resolution CT scanning with EOE‐13 allowed calculation of tumor doubling times, and therefore more precise management of cancer patients with metastases.

Development and Experimental Evaluation of a Contrast Medium for Computed Tomographic Examination of the Liver and Spleen

A lipoid based contrast material containing 53% of ethiodized oil in emulsion form was developed for computed tomography (CT) of the liver and spleen and tested in rabbits and monkeys. An intravenous dose of 0.2 ml/kg selectively opacified the liver and spleen, resulting in an average increase of 23 EMI units (500 scale) in the attenuation of the liver and a higher increase in the attenuation of the spleen. When injected into rhesus monkeys with carcinogen induced hepatomas there was a significant improvement in the visualization of the tumor, and small lesions, undetectable on the preliminary CT scan, became visible. Toxicity studies are in progress.

Detection of orbital and intraocular foreign bodies by computerized tomography.

Localization of intraocular and orbital foreign bodies with computerized tomography (CT) was evaluated in eight patients and an experimental model. CT examination was particularly helpful in cases with multiple similar foreign bodies and in identifying foreign bodies too radiolucent to be seen by standard skull x-rays. Limitations of CT technique included insufficient resolution to localize a foreign body immediately adjacent to the sclera as either intraocular or extraocular, and obscuration of a small foreign body by artifacts from an adjacent, larger foreign body.

Segmental hyperlucent defects in the liver.

When lucent defects in the liver have a segmental configuration, they may be on an ischemic basis and related to decreased vascular perfusion. Portal venous inflow, by virtue of its low pressure, is particularly susceptible to diversion by focal intrahepatic masses, intravenous thrombi, or external compression. Innovative operative techniques for tumor enucleation may also result in lucent defects that can be confused with, or conceal, pathology. A hypothesis relating such defects to diminished portal inflow and reduced glycogen content is proposed.

Computed Tomographic Demonstration of Hepatic Tumor with the Aid of Intravenous lodinated Fat Emulsion

Computed tomography showed Improved visualization of carcinogen-Induced hepatoma in monkeys following intravenous injection of an experimental contrast material, AG 60–99; selective opacification of the liver and spleen was accomplished with a dose of ≥ 0.1 mi/kg, a fraction of the dose used in conventional x-ray tomography. This marked reduction was made possible by the improved density resolution of the CT scanner. This may be the first organ-specific contrast material intended primarily for use with CT scanners.

Biodistribution study of Ethiodized Oil Emulsion 13 for computed tomography of the liver and spleen.

Biodistribution studies were conducted with a new intravenous lipoid contrast material currently undergoing clinical trials in four hospitals. The contrast material selectively opacifies the liver and spleen for computed tomographic examination. The experiments were performed on rats with 125I-labeled ethiodized oil emulsion. The study showed that the liver accumulates nearly 80% of the injected iodine within 15 min of the injection and retains a high concentration over 3 h. The second highest concentration was found in the spleen. More than 99% of the iodine is eliminated from the liver and spleen within 48 h, primarily through the kidneys.

Use of Intravenous Liposoluble Contrast Material for the Examination of the Liver and Spleen in Lymphoma

An experimental contrast material has been developed that, after intravenous injection, selectively opacifies the spleen and liver on computed tomography (CT). The contrast material contains iodinated ester of poppy seed oil in an emulsified form. Clinical trials were recently initiated to test the value of this contrast agent in Hodgkins and non-Hodgkins lymphomas. We present here two of our initial patients in whom we found lesions in the spleen or liver following the infusion of the experimental contrast material that were not visualized on the precontrast and urographic contrast material enhanced CT scans.

Intravenous hepatosplenography. Experiment evaluation of a new contrast material.

A new, lipoid-based experimental contrast material (AG 60-99) was intravenously infused into 29 rhesus monkeys. The injections resulted in dense hepatosplenograms, preserving diagnostic quality for over 24 hours, and enabling routine utilization of tomography. This technique is capable of demonstrating simulated hepatic masses as small as 5 mm in diameter in vivo. Limited histopathologic and toxicity studies showed no serious or lasting toxic manifestations from AG 60-99 and none of the animals died from it. AG 60-99 is felt to be potentially useful in the radiographic detection of early metastic or lymphomatous involvement of the liver and spleen.