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F V Gabor

Publications and source records attributed to F V Gabor.

7 recordsLinked to original sources
PubMed1994

Image analysis and categorization of ventilation-perfusion scans for the diagnosis of pulmonary embolism using an expert system.

UNLABELLED: An expert system was developed that interprets ventilation-perfusion lung scans. The use of such scans for suspected pulmonary embolism is ideal for computer-assisted diagnosis by expert systems. The data are digital, only a single disease entity is diagnosed or excluded, and well-established diagnostic criteria already exist for visual interpretation that can be easily integrated into an expert system. METHODS: This expert system is divided into two modules. The first module is responsible for image analysis. Analysis was performed on the eight standard perfusion images and on single-breath, equilibrium and 3-min washout ventilation images. Each image was analyzed for the presence of regional perfusion or ventilation defects, as determined by pixel values that fell 2.2 s.d. below the mean (or above the mean in the case of washout images) compared with a database of normal studies. The defect size, segment involved and number of defects were determined. Ventilation and perfusion images were then compared to determine whether defects were matched or mismatched. The second program module applied the modified Biello's criteria to the data and categorized the scan as normal to low, intermediate or high probability. RESULTS: A total of 80 patients were prospectively studied. An 81% (65 of 80) correlation was obtained when the results of the expert system were compared with visual interpretations made by three experienced nuclear medicine physicians. CONCLUSION: This study shows that the interpretation of ventilation-perfusion lung scans by an expert system is possible. The technique holds the promise of reducing interobserver variability and assisting less experienced observers in the interpretation of such scans.

Expert Systems↗
PubMed1994

The efficacy of indium-111-polyclonal IgG for the detection of infection and inflammation.

UNLABELLED: The purpose of this study was to determine the efficacy of 111In-polyclonal immunoglobulin (IgG) for the diagnosis of infection or inflammation. METHODS: Fifty-three patients with suspected infection were prospectively studied. Each underwent an 111In-polyclonal IgG study; biopsy, surgery, additional nuclear medicine scans and radiographic studies were used to confirm the IgG scan results. RESULTS: The polyclonal IgG scan had a sensitivity of 97.9% and a specificity of 94% for infection or inflammation. When only infection or severe inflammation such as bowel infarction was considered, the sensitivity remained the same but the specificity fell to 83%. Chronic infections were detected equally as well as acute infections. Antibiotics, steroids, anti-inflammatory agents, diabetes and diminished renal function did not affect scan sensitivity. There were no adverse reactions to the radiopharmaceutical. Three patients underwent extended imaging. Their scans stayed positive for an average of 8 days. Three patients treated for infection had their scans turn negative on repeat study, confirming the efficacy of their antibiotic therapy. CONCLUSION: Indium-111-polyclonal IgG is an effective imaging agent of infection and/or inflammation that is useful in a variety of infections and in severe inflammatory diseases. The ease of preparation and safety make it an attractive alternative to labeled leukocytes.

Adult↗
PubMed1993

The use of computer-assisted diagnosis in cardiac perfusion nuclear medicine studies: a review (Part 2).

Computer-assisted diagnosis (CAID) is commonly used to evaluate cardiac nuclear medicine studies such as thallium perfusion scans. Part I of this series (Journal of Digital Imaging, Vol 5, No 4, pp 209-222) reviewed the basic theory underlying CAID in nuclear medicine and its use in planar thallium imaging. This review discusses the application of CAID to SPECT perfusion studies.

Artifacts↗
PubMed1993

The use of computer-assisted diagnosis in cardiac perfusion nuclear medicine studies: a review (Part 3)

Computer-assisted diagnosis (CAID) is commonly used to evaluate cardiac nuclear medicine studies such as thallium perfusion scans. Part 1 of this series (Journal of Digital Imaging, 5:209-222, 1992) reviewed the basic theory underlying CAID in nuclear medicine and its use in planar thallium imaging. Part 2 discussed the application of CAID to SPECT perfusion studies (Journal of Digital Imaging, 6:1-15, 1993). This article reviews new variations of CAID programs for SPECT imaging and the application of expert systems and neural networks to CAID of nuclear medicine perfusion studies.

Algorithms↗
PubMed1993

Cerebrovascular accident associated with dipyridamole thallium-201 myocardial imaging: case report.

A patient with known aortoiliac occlusive disease and hypertension suffered a cerebrovascular accident 6.5 min after the administration of intravenous dipyridamole during a 201Tl myocardial study. Despite aminophylline administration, the patient developed a completed stroke. The mechanism most likely responsible for precipitating this patient's stroke is dipyridamole-induced vascular steal. Although dipyridamole-201Tl myocardial imaging is relatively free of major complications, the morbidity and mortality associated with a cerebrovascular accident is significant. The possibility of precipitating a cerebrovascular accident during dipyridamole-201Tl imaging should be considered in all patients with significant risk factors for stroke before performing a dipyridamole cardiac study.

Cerebrovascular Disorders↗
PubMed1992

The use of computer-assisted diagnosis in cardiac-perfusion nuclear medicine studies: a review.

The use of computer-assisted diagnosis has become widespread in cardiac nuclear medicine. Quantitative programs are commercially available for ventriculography, phase analysis, and thallium 201 perfusion studies. The goal of these programs is to eliminate interobserver variability by objectively analyzing the studies without causing a loss of accuracy. In addition, by using quantitative data not apparent on visual inspection, some programs attempt to increase sensitivity for disease above that possible by the visual reading of images. Programs that analyze perfusion studies to detect coronary artery disease have received the most interest. Results have varied, but sensitivities as high as 95% have been reported. This review discusses the techniques of computer-assisted diagnosis for thallium 201 myocardial-perfusion studies. The circumferential and washout profile methods are discussed in detail.

Animals↗