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K F Neufang

Publications and source records attributed to K F Neufang.

At least 55 records · Page 3Linked to original sources
PubMed1987

[Complications of intravenous digital subtraction angiography--results in 500 patients].

500 patients were studied respectively for complications of intravenous digital subtraction angiography (IV-DSA) performed with non-ionic contrast media, using a central venous injection technique. In 21 patients (4.2%) during or shortly after the procedure 23 systemic, 1 neurologic, and 7 local complications occurred. In addition 1 patient developed acute renal failure 26 hours after the IV-DSA, whereas 4 patients later showed on thromboses of the catheterised vein. No permanent neurologic or systemic complications and severe allergic reactions were seen.

Acute Kidney Injury↗
PubMed1987

[Complications of brachiocephalic catheter angiography using a non-ionic contrast medium].

In 713 patients 749 catheter-arteriographies of aortic-arch and cerebral vessels were performed using non-ionic contrast media. The patients were examined either with DSA or conventional film techniques. In 80 examinations of 76 patients complications or side-effects were noted, which resolved completely within one hour in 69 cases, showed a duration up to 7 days in 6 cases, and persisted longer than 7 days in 5 patients. Neurological complications were seen in 6.4% of the studies. There was no death. Patients, who received anti-hypertensive drugs before or during angiography and patients with a pathological angiogram had a significantly higher complication-rate. The rising number of patients with atherosclerotic cerebrovascular disease showed an unfavorable effect upon the overall complication-rate. The use of a non-ionic contrast medium did not drastically lower the rate of neurological complications.

Adult↗
PubMed1987

Radiation doses to the eye lenses in computed tomography of the orbit and the petrous bone.

Standard CT examinations of the orbit and the petrous bone were simulated with a tissue-equivalent human skull phantom on a Somatom DR 2 scanner. The orientation of the scan planes and the scan parameters including thickness, number of slices and mAs were varied according to the assumed diagnostic problems. The total radiation doses in the region of the eye lenses were measured with thermoluminescent dosimeters. If the globes are located within the X-ray field, the total radiation doses received by the lenses increased with the number and the thickness of the slices and the mAs. The highest radiation doses were found in contiguous thin-section scans of the orbit in axial (52 mGy) or direct coronal (47 mGy) orientation. In cases where the globes were located outside the X-ray field, the radiation doses received by the eye lenses could be reduced by a factor of 16, resulting in only 3.1-3.4 mGy for a complete axial study of the inner ear. Recommendations are given how to reduce the radiation exposure to the eye lenses without loss of diagnostical information.

Humans↗
PubMed1986

Somatic and genetic radiation exposure of the patient in digital subtraction angiography (DSA)

The somatic and genetic radiation exposure of patients undergoing Digital Subtraction Angiography (DSA) and traditional Film Arteriography (FA) of cranial, cervical, thoracic and abdominal vascular territories are compared. The radiation doses absorbed within the critical organs--red bone marrow, lung, thyroid gland and female breast--and in the gonads were measured using an anthropomorphic Alderson phantom. A Somatic Dose Index was calculated in order to estimate the somatic radiation risk. The somatic radiation exposure depends upon the location of the critical organs with respect to the entrance site of the x-ray beam, and can be reduced by an appropriate choice of the angiographic projection. Under this condition, the radiation exposure of the patient during DSA can be lower than during FA. For renal DSA an a.p. projection, the use of an abdominal compression device and careful caudal shielding of the field are advocated.

Cerebrovascular Disorders↗
PubMed1986

Image quality in intravenous renal DSA. A critical analysis of 300 examinations.

Renal venous DSA yields diagnostically adequate results in an unselected population in more than 85% of cases. Image quality is compromised predominantly by inadequate contrast enhancement, motion artifacts from the stomach and the bowel, and obesity. The effect of these factors increases with patient age. Selection of patients, careful bowel preparation, the use of a compression device and intravenous spasmolytics are recommended to improve image quality. The possible contributions of the injection technique, pulsed DSA and advanced post-processing facilities are discussed.

Adolescent↗
PubMed1986

[Geometry of eccentric vascular stenoses in various projections--significance for angiographic assessment of the degree of stenosis, especially using digital subtraction angiography].

A mathematical model is used to predict the angiographic appearance of plaque-like lesions and eccentric vascular stenoses. The virtual stenotic areas and the degree of stenosis are calculated for different projection angles varying between 0 degree--x-ray beam tangential to the lesion--and 90 degrees--x-ray beam incidental to the lesion. Eccentric stenoses are underestimated if the lesion is not tangential to the x-ray beam. Eccentric stenoses can be overestimated if automated programmes are based on a circular configuration of both the normal and the stenotic lumens. In this model the best estimation is obtained if the stenotic lumen is assumed to be elliptic, and if biplane rectangular projections are available.

Angiography↗
PubMed1985

[Differential diagnosis of masses in the head of the pancreas area].

Masses in the head of the pancreas area may be caused by neoplastic, inflammatory and a variety of other processes originating within the pancreas or in adjacent structures and organs. CT following intravenous bolus injection of the contrast agent and oral staining of the small bowel allows the precise anatomic localization of the lesion and helps to evaluate its dignity and pathology. Nevertheless, frequently the final can be established only at open surgery and by histopathologic examination of the resected specimen.

Acute Disease↗
PubMed1985

Indications for intravenous and intraarterial digital subtraction angiography (DSA) in the diagnosis of cerebrovascular insufficiency. A new diagnostic concept including ultrasound.

For screening of arteriosclerotic lesions of the carotid bifurcation duplex scanning (B-mode imaging plus doppler flow analysis) is the method of first choice, because it is really noninvasive and offers the same results as intravenous DSA (IV DSA). IV DSA should not be performed as a screening procedure unless ultrasound examinations are not available or are inadequate. Except for patients with isolated unilateral stenosis of the internal carotid artery near the bifurcation confirmed with both duplex scanning and IV DSA, arteriography is required for therapy planning. Aortic arch angiogram, selective extra- and intracranial carotid arteriography and--if necessary--vertebral and subclavian arteriography can be performed with intraarterial DSA (IA DSA). The application of DSA to catheter arteriography will help to reduce further the potential risk of adverse reactions related to high intravasal contrast doses specially in the cerebral circulation, but will not turn arteriography into a risk-free procedure. Postoperative examinations of the carotid bifurcation can be performed with ultrasound as well as with IV DSA. Extracranial bypasses are best demonstrated with IV DSA. Extraintracranial bypasses can be demonstrated only with IA DSA.

Angiography↗
PubMed1984

[Computed tomographic findings in mitral valve disease].

In 38 patients suffering from mitral valve disease the findings of cardiac CT scans were compared to the results of echocardiographic, standard roentgenographic, and cineangiocardiographic studies as well as to intraoperative and histological findings. CT proved to be superior to the other imaging modalities in detecting mitral calcifications and in demonstrating the morphological changes, but cannot replace cardiac catheterization as it does not yield haemodynamic data. The indication for CT in mitral valve disease therefore is restricted to cases with extremely enlarged left atria in which the other methods do not provide satisfactory visualization, and to patients with suspected intracavitary thrombus or tumor.

Adolescent↗
PubMed1984

[Aortic arch angiography in the preoperative diagnosis of cerebrovascular diseases. Comparison of the conventional technic and intra-arterial DSA].

Demonstration of the aortic arch is necessary in the investigation of cerebrovascular insufficiency for showing the origins and course of the cerebral arteries and for detecting steal syndromes and anatomical variations. Intra-arterial DSA is comparable in this respect with the traditional film technique; it has the advantage of reducing contrast doses by 75% and of reducing film costs and the examination time. Reliable evaluation of the carotid bifurcations is possible in less than half the cases. Selective carotid angiography cannot be replaced, therefore, by this technique. Selective angiography is also necessary for the pre-operative study of the intracranial vessels.

Aorta, Thoracic↗
PubMed1984

[Possibilities and limitations of the differential diagnosis of grouped intramammary microcalcifications].

In recent years, the first author of the present paper has developed a system for the differential diagnosis of benign and malignant lesions based on the radiological patterns of grouped microcalcifications. The value of the system in actual practice has been tested in a "blind" study of 297 mammograms with grouped micro-calcifications in whom the diagnosis had been verified by operation and histology. Use of this system saved 63% of biopsies. Amongst 42 carcinomas, only one was erroneously regarded as benign. The sensitivity of the system in this study was 97.6% and its specificity was 73.3%. The radiological symptoms associated with the correct and false diagnoses have been analysed.

Breast Neoplasms↗
PubMed1984

[Roentgen diagnosis of the veins in the upper half of the body using the digital subtraction technic - digital subtraction phlebography].

Digital subtraction phlebography (DSP) is suitable for x-ray examinations of the shoulder veins and the veins of the upper mediastinum. Acute thromboses, post-thrombotic syndromes, malformations and collateral systems can be demonstrated. The main advantages of DSP over conventional phlebography are the possibility of using contrast medium solutions of low osmolarity enabling pain-free examinations not involving the risk of thromboses, the saving in the amount of contrast medium, and the reduction of examination time.

Adolescent↗