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K Voigt

Publications and source records attributed to K Voigt.

At least 109 records · Page 6Linked to original sources
PubMed1988

[Value of the dual-energy method in quantitative CT studies of the brain].

Using a dual-energy (DE) method, conventional polyenergetic and monoenergetic beams were used to obtain data in phantom and clinical CT studies and to prove the benefit of this method in quantitative cranial CT. Conventional polyenergetic (85 kVp and 125 kVp) and simulated monoenergetic images were reconstructed from the measurements. The noise in the monoenergetic images was lowest at 72 kVp. The interindividual white-gray differentiation varied less in DE forms than in polyenergetic images, whereas the noise was of the same order of magnitude in both types. As can be derived from our results, DE may be clinically useful in diagnosing abnormal lucency of the white matter in newborn and premature infants.

Adult↗
PubMed1987

Advantage of magnetic resonance imaging in the diagnosis of cerebral infections.

18 patients with cerebral infections were investigated with a 1.5 Tesla-Magnetom. The results are compared to CT-findings obtained at the same time. In the majority of cases (n = 11) MR is superior to CT because it allows earlier detection of the disease, a more exact definition of the spread and a more detailed representation of complex inflammatory processes. MRI should rank first among all examination methods, especially in the determination of herpes simplex-encephalitis as it allows earlier detection and treatment of this disease.

Adult↗
PubMed1987

Early diagnosis of herpes simplex encephalitis by MRI.

The mortality rate of herpes simplex encephalitis (HSE) may be reduced by antiviral therapy, but early administration of the drug and therefore early diagnosis are essential. In our experience with four cases, MRI is the most sensitive noninvasive test in early diagnosis of HSE due to its high sensitivity to inflammatory increased brain water content, and it is superior to CT in localizing the pathognomonic lesions of the limbic system.

Child↗
PubMed1987

Magnetic resonance imaging of spinal meningiomas and neurinomas. Improvement of imaging by paramagnetic contrast enhancement.

The detection and delineation of spinal tumors by magnetic resonance imaging (MRI) after intravenous administration of gadolinium (Gd)-diethylenetriaminepenta-acetic acid (DTPA) is demonstrated in eight cases of neurinoma or meningioma. The advantages of Gd-DTPA-enhanced MRI over other MRI techniques used in more than 100 cases of spinal cord diseases are described.

Adult↗
PubMed1986

[Spontaneous subarachnoid hemorrhage as a symptomatic manifestation of an acoustic neurinoma].

Subarachnoid hemorrhages (SAH) due to intracranial tumors are very rare. We report the clinical, neuroradiological and histological findings of an acoustic neurinoma, the initial and manifestating symptom of which was an acute SAH. In the literature we found only eight further cases of acoustic neurinomas with spontaneous SAH. The causes of the SAH are discussed; and we compare our findings to those in the literature.

Cerebral Angiography↗
PubMed1984

[Posterior fossa masses. Comparison of magnetic resonance tomography and computed tomography].

The results of magnetic resonance imaging, using a 0.5 Tesla superconductive magnet in 6 patients with clinical (6), angiographic (6) and histologic (4) diagnosis of posterior fossa tumors were reviewed and compared with x-ray computed tomography. Optimal visualization of normal and abnormal anatomic relationships and the possibility and value of calculated T1- and T2-pictures with the aid of spin-echo-technique are discussed.

Adult↗
PubMed1983

The significance of somatosensory evoked potentials for localization of unilateral lesions within the cerebral hemispheres.

Thirty patients with unilateral lesions of the cerebral hemisphere and clinical signs of an affected somatosensory system (mainly disturbances of kinesthesia and stereoesthesia) were investigated. SEP recordings were abnormal in 27. The degree of sensory loss (especially kinesthesia) correlated well with the SEP abnormalities in 26. These SEP abnormalities could be segregated into 4 groups (types 1-4). A type 1 SEP with pathological evoked potentials from P15 on (but a normal P13/14 complex with ear- or extracephalic reference recordings) correlated with lesions of the thalamus, the internal capsule, and the centrum semiovale. A type 2 SEP characterized by loss or severe attenuation of N20 and the following components was found in patients with lesions of the postcentral gyrus. A variant (type 2a) showed isolated loss of N20, but preserved subsequent components and may be due to lesions restricted to area 3b. A third pattern of SEP abnormality is characterized by a preserved primary cortical response and loss of all the subsequent potentials. It is assumed to correlate with lesions of the parietal association cortex. In only 1 case was a type 4 SEP found, with pathological features from N3 (N55) on, caused by an ischemic stroke in area 39. Loss of all evoked responses after P13/14, including P15, suggests a lesion between thalamus and centrum semiovale. Lesions located close to the postcentral cortex lead to a loss of N20 and a variable cut off of the rising negativity following P15. Preservation of the primary cortical complex and distortion or loss of the later components point to a parietal lesion. Severe disturbances of kinesthesia and stereognosia in patients with a normal primary cortical complex and isolated abnormality of the following potentials suggests that the adjacent association cortex may be important for the perception of this complex somatosensory information. Thus the neuronal activity underlying the primary cortical response does not suffice for perception of motion and for stereoesthesia.

Adult↗
PubMed1983

[Value of densitometry in the computer tomographic differentiation of paracranial space-occupying lesions. Experimental phantom studies and clinical evaluation].

Hardening of the beam is a major disturbing effect in densitometry close to the calotte. This phenomenon is demonstrated in a phantom, and its theoretical base is discussed. If possible sources of error are considered and reduced by means of appropriate measuring conditions, measurement of density will furnish useful additional data in CT examination. The value of CT densitometry is demonstrated via follow-up observations; after an operation of a glioma of the optic nerve, a child developed hygromas complicated by superinfection which subsequently became horny or calcified.

Absorptiometry, Photon↗
PubMed1983

[How reliable is the diagnosis of spinal angiomas in the myelogram?].

Using water-soluble contrast media for thoracic myelography vascular structures can be outlined within the subarachnoid space in about 30% as distinct and in another 30% as faint contrast filling defects. The localization corresponds to the results of anatomical studies demonstrating the largest vessels in the lower thoracic region and at the lumbar enlargement. The extreme variability of size and course of spinal cord vessels can cause difficulties in separating normal and angioma-like vascular pattern in myelographic examinations. Out of 100 unselected cervico-thoracic myelographies, examples of normal vascular patterns are given and compared to pathological findings of angiographically verified angiomatous malformations. The limitations of diagnostic reliability are given by anatomical factors like variability of vessel size or width of the subarachnoid space, by secondary spinal arachnitis or by the differentiation of cord tumours with vascular congestion. Furthermore, inadequate angiographic studies can result in misinterpretation of myelograms. In cases of negative arteriograms other affections leading to raised pressure in the azygos- or caval vein should be considered.

Hemangioma↗
PubMed1982

[Neuroradiology, clinical picture and pathology of cerebral venous angiomas].

Twelve cases of venous angioma of the brain are presented. The neuroradiological and clinical findings in our series as well as in 45 previously reported cases are summarized. Angiography shows a normal arterial phase but consecutively a network or medusa-like pattern of numerous dilated medullary veins. converging towards one or several draining vessels with transcerebral course. The angiographic appearance is characteristic but not uniform, showing subgroups with faint blush, early filling veins and drainage into different directions. Some cases of venous malformations cannot be classified on the basis of angiographic findings and differentiation of telangiectases or cavernomas may be difficult. CT findings are non-specific, but contrast-enhanced CT almost invariably shows an enlarged transcerebral vessel, suggesting the presence of venous malformation. The lesion has to be classified as a vascular hamartoma. Although not an uncommon finding at autopsy venous angioma has been considered rare, because its clinical and radiological characteristics are little known. Though it may be asymptomatic, more than 30% of the reported cases (50% in our series) suffered from epileptic seizures. In about 10% of all cases symptoms of intracranial hemorrhage related to venous angioma were observed.

Adolescent↗
PubMed1981

Functional anatomy of extracranial arteries in occlusive vascular diseases by direct continuous wave Doppler sonography.

Doppler sonography of supratrochlear and neck arteries permits a determination of the direction and speed of flow. By compression of distal branches, the external carotid artery can be recognized, the occipital artery can be distinguished from the vertebral, and the direction of flow in the supratrochlear artery can be ascertained regardless of the artery's coiling. Compression of the arm can reveal subclavian steal. In order to localize a stenosis the vessel is followed by the probe. The accuracy of Doppler sonography is approximately 96%, and while the method may miss the diagnosis of slight stenoses and ulcerations, it nevertheless appears to be superior to all other indirect, noninvasive techniques that are currently available.

Aged↗
PubMed1981

[Interventional neuroradiology. I. Cranio-facial embolisations (author's transl)].

Technical and methodological procedures as well as results and follow-up studies of superselective angiographies and embolisations with different materials (gelfoam, lyophilised dura, silicone-elastomer) in 105 patients with vascular lesions (arteriovenous angiomas and fistulas, capillary haemangiomas), benign (glomus tumors, fibromas, meningeomas) and malignant tumors (sarcomas, metastases) of the cranio-facial region are described. Due to the clinical findings and follow-up studies up to three years there were different palliative and curative results which are exemplified. Therefore, a uniform performance of the embolisatory interventions is refused. The arterial approach, the different catheter systems as well as the actual technical procedure of the embolisations, with or without superselective pharmacoangiographies, has to be chosen according to the individual manifestation of the lesions and their anatomical and pathological conditions.

Cerebral Angiography↗