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J P Hedde

Publications and source records attributed to J P Hedde.

At least 37 records · Page 2Linked to original sources

[Comparison of the computed tomographic changes and the clinical course following the irradiation of intracranial tumors and metastases].

The authors compared the clinical courses and the CT courses recorded at the same time in patients with primary or secondary cerebral tumors. 69 patients improved their neurologic state under external radiotherapy, 35 patients remained unchanged, and 8 patients had a deteriorated condition. The changes in computed tomography and the modifications of the clinical state of patients corresponded only in 55% of all cases. The reasons are discussed. Some patients suffered from fatigue and weak concentration about three months after the end of radiotherapy, in some cases even the neurologic state was deteriorated. These manifestations known as "early delayed reaction" were reversible.

Astrocytoma↗

[Stenosis of the carotid arteries in digital subtraction angiography].

The quality of intravenous digital subtraction angiograms was sufficient for diagnostic evaluation in 90%. The accuracy of the method was 90% for the internal carotid artery. 40% of the internal carotid arteries showed stenoses, whereas the common and external carotid arteries were not narrowed in 90%. On behalf of these data the authors consider that i.v. DSA of the carotid vessels is a suitable screening method for carotid arterial occlusive disease.

Brain Ischemia↗

[Measurement of regional cerebral blood flow as a supplement to carotid angiography in assessing cerebrovascular insufficiency].

The examination of 91 patients was undertaken in order to establish the relevance of tomographical measurement of the regional cerebral blood-flow, following inhalation of 133Xenon, as a complementary method to the conventional carotis-angiography. In many cases the findings revealed a more precise or even deviating judgement on the hemodynamic relevance of stenosis and obliteration than was proved only by angiography. Especially in the stages I and IV of cerebrovascular disease of the a. cerebri anterior, a. carotis interna and a. carotis communis the rCBF-measurement seemed to be an important parameter for the decision between conservative and surgical therapy as a prognostic parameter for the individual risk of many patients to suffer a cerebral infarction.

Carotid Arteries↗

[Comparison of computed tomography, automated multisector scanner (Octoson) and conventional ultrasound in pancreatic diseases].

Two hundred and eighty-six patients suspected of having pancreatic disease were examined by computed tomography, Octoson and conventional ultrasound. Computed tomography with angio-CT had the highest sensitivity (87.4%). The Octoson, with a sensitivity of 77.16% was better than conventional ultrasound, which had a sensitivity of 65.35%. Specificity for CT was 91.2%, for the Octoson 88.67% and conventional ultrasound 85.5%. The better results of the Octoson examination are due to the thin air gap when the patient is prone and the greater focal length of the large transducer and the somewhat more stable focus.

Acute Disease↗

[Noninvasive tomographic measurement of regional cerebral blood flow].

The measurement of the regional cerebral bloodflow by means of the dynamic single-photon-emission-computed tomography is a method of examination which is completely free of risk for the patient, causes no inconvenience and can be repeated whenever it seems necessary. This method gives a quantitative explanation for the distribution of the effective cerebral perfusion and can only be substituted by the very complicated positron-emission-computed tomography. As well as the exact assessment of the hemodynamic relevance of cerebral vascular disease, this method enables us to prove whether or not in various types of psychiatric disorders an interference in the regional perfusion exists. This method can also contribute to the clarification of pathogenic mechanisms, as well as to the nosological classification of specific psychopathological conditions.

Adult↗

[Comparison of 133xenon and 123I-isopropylamphetamine for measuring regional cerebral circulation].

In 26 patients the regional cerebral blood flow was measured using 123I-isopropyl-amphetamine. The measurement was performed with a dynamic single photon emission tomograph. In 16 patients we compared the findings with the results of the tomographic 133Xe-Clearance. Both methods seem to be suitable for the measurement of the effective perfusion and gave similar results. In the case of the tomographic 133Xe-clearance we need a more specialized technical equipment whereas the permanent costs are lower and the performance less complicated. Besides the applicability of this method is more universal. On the contrary the use of 123I-isopropyl-amphetamine makes a higher resolution possible depending on the available equipment and does not need an ability to cooperation of the patient. With the presently disposable radionuclides the hope was not yet adequately accomplished, to get a tomographic in-vivo-information of cerebral metabolic and receptor-functions by means of SPECT.

Amphetamines↗

[Diagnostic significance of intravenous digital subtraction angiography of the supra-aortic extracranial vascular system. Comparative study of i.v. DSA and plain film angiography].

Digital intravenous subtraction angiography (DSA) and conventional film angiography were used to evaluate the diagnostic reliability of DSA-examinations. In 90% of 650 DSA-angiogramms the image quality was diagnostic. For 124 carotid angiographies a comparison of both methods was possible and gave a sensitivity of 87%, a specificity of 96% and an accuracy of 90% for the DSA examinations. The authors believe that digital subtraction angiography is suitable as a screening method for supraaortal vascular occlusive diseases.

Aged↗

The automated waterpath scanner (Octoson)--advantages and limitations in diseases of the liver, pancreas and gallbladder.

In a comparative study of 591 examinations the Octoson and a conventional ultrasound scanner were analysed. Examinations with the Octoson showed a sensitivity of 92% and with a conventional ultrasound scanner a sensitivity of 82% in diseases of the liver. With the long focus of the Octoson's large aperture transducers, it is possible to demonstrate both superficial and deep subdiaphragmatic metastases. It is difficult, however, to find the optimal scanning angle with this system, and for this reason examinations undertaken in disorders of the gallbladder and bile ducts require considerably more time. In pancreatic disease (Octoson sensitivity: 77%; conventional ultrasound scanner sensitivity: 65.35%) the favourable air distribution in the stomach and transverse colon is advantageous when the examination is performed with the patient in the prone position.

Bile Duct Diseases↗

[Results of myocardial perfusion scintigraphy (author's transl)].

Myocardial perfusion scintigraphy by means of the microsphere technique is a valuable method for detecting regional myocardial scars. The use of the microsphere technique is indicated in all patients who have had myocardial infarction and before coronary bypass operations. In a certain group of patients with severe but atypical angina pectoris and a normal coronary arteriogram and in some arrhythmias the perfusion scintigram can provide information on changes coronary microcirculation. The assessment of myocardial blood flow redistribution under pharmacological intervention is a further indication for the microsphere technique.

Angina Pectoris↗

[Myocardial perfusion scintigraphy - methods and fundamentals (author's transl)].

Myocardial perfusion studies with labelled particles make a detailed analysis of the distribution of myocardial perfusion possible. Methodical and physiological fundamentals are described and the reliability of the method is shown by double radionuclide imaging. LAD-stenoses (greater than 70%) show a decreased activity in the distal areas of the LAD (on the average 36,5 +/- 10,3% in contrast to 59 +/- in normals). Mean local activity is 14,9 +/- 1,8% within scars. Scars and hemodynamically effective stenoses can be imaged with high sensitivity. Total defects (smaller than 15% of the activity maximum) correspond to a scar. A moderate reduction of uptake (15--50% of the activity maximum) does not allow any differentiation between scar and reversible diminution of perfusion.

Coronary Circulation↗

[The reliability of myocardial scintigraphy with thallium201, A comparison with lacvocardiography and perfusion scintigraphy (author's transl)].

Eighteen patients were investigated by laevocardiography, perfusion scintigraphy and with a 201thallium scan. In four patients with normal contractility of the left ventricle, normal uptake of 202thalium was found in every patient. Hypokinesia of the anterior wall or apex of the ventricle showed normal uptake on the 201thallium scintigram in four out of five patients. It follows that it is not usually possible to diagnose hypokinetic mural portions on 201thallium scintigrams without quantitative analysis. Our experience up to date with areas of akinesia has shown that it is possible to demonstrate areas of scarring (as negative contrast) in seven out of nine cases.

Angiocardiography↗

[Significance of inhalation and perfusion scintigraphy for the diagnosis of pulmonary embolism (author's transl)].

Inhalation and perfusion scintigrams, general radiological examination of the thorax and an EKG were done on 43 patients with clinically suspected pulmonary embolism. In 11 cases, the clinical diagnosis could be confirmed on the basis of the scintigraphic examination. In the remaining 32 patients, an embolich event could be excluded by pulmonary scintigram, radiological examination and later the clinical course. A synopsis of clinical observations, X-ray and scintigraphy, therefore, permitted a basically reliable diagnosis of pulmonary embolism; selective pulmonary angiography should be used only in exceptional cases.

Adult↗