Search PubMed⌕ Search

Biomedical subjects

A Thron

Publications and source records attributed to A Thron.

153 records · Page 9Linked to original sources
PubMedDate not supplied

[Cerebral vein and sinus thrombosis--an important cause of benign intracranial pressure increase in childhood].

The syndrome of raised intracranial pressure without any space-occupying lesion (pseudotumor cerebri) is still of unknown etiology. To some degree, secondary causes can be found. With respect to the therapeutical possibilities, a clinically important cause is the thrombosis of a major cerebral sinus. In children it is sometimes associated with otitis media. However, clinical signs of mastoiditis can be missed because of previous antibiotic treatment. We observed 11 children with pseudotumor cerebri. Four children suffered from an occlusion of a lateral major sinus after otitis media. The treatment with heparin in the acute stage and later on with acetylsalicylic-acid led to complete recovery. Our results suggest that the thrombosis of a major cerebral sinus induced by an otitis media is a frequent cause of pseudotumor cerebri in children and should be excluded by MRI or angiography in any doubtful case. In contrast to the treatment of adults, long term anticoagulation is not necessary.

Adolescent↗
PubMedDate not supplied

[Therapy of choroid plexus carcinoma in childhood. Case report and review of the literature].

Carcinomas of the plexus choroideus (PCC) represent the rare malignant variety of plexus choroideus papillomas and take a particularly unfavourable course. Tumors of the plexus choroideus account for about 2-4% of all primary brain tumors in children and 0.5% of those in adults. The PCC is more frequent in children than in adults; the authors found reports on 72 cases of PCC in children and on 16 cases in adults. In most cases the PCC is located in the lateral ventricles. The symptoms caused by PCC are non specific and appear as those of increased intracranial pressure (on the basis of hydrocephalus hypersecretorius and/or occlusivus). As the nature of the tumor cannot be identified by means of medical imaging, the diagnosis is usually set up histologically. Prognosis is poor for patients treated only by surgery, which in most cases has been performed as subtotal resection of the tumor. So the necessity for an oncological strategy combining surgery and 'adjuvant' therapy arises. The authors report the application of such a strategy in the case of a three-year-old boy with a PCC of the left lateral ventricle. After nearly four years of remission, the boy died of meningeosis carcinomatosa. This course underlines the malignancy of this tumor; even after years the poor prognosis can still be diminished by the spread of meningeal metastases. In a survey of the case reports published in literature the patients' data, their therapy and the outcome are demonstrated.(ABSTRACT TRUNCATED AT 250 WORDS)

Carcinoma↗
PubMedDate not supplied

Immediate postoperative CT contrast enhancement following surgery of cerebral tumoral lesions.

PURPOSE: Our goal was to evaluate the immediate postoperative contrast enhancement behavior of cerebral lesions and to gain further information about contrast enhancement in patients under general anesthesia. METHOD: In the early postoperative period, CT scans with the without contrast medium were performed in 46 patients. The time interval between surgery and postoperative CT imaging ranged from 1 to 7.5 h (mean 4 h). Nineteen patients were under general anesthesia during CT investigation. RESULTS: In the early postoperative period, contrast medium leakage into the tumor resection cavity was noted In 14 patients (30%). Another phenomenon that was observed was the appearance of a strong demarcation and distinct contrast of gray against white matter in 24 patients (52%). This characteristic, global contrast enhancement of the cerebral cortex, occurred in 17 of 19 patients (89%) investigated under general anesthesia. CONCLUSION: In immediate postoperative CT scans, contrast medium leakage due to extravasation of contrast medium into the tumor resection cavity can be detected early. Moreover, a global contrast enhancement of the cerebral cortex can be detected as a frequent pattern in patients investigated under general anesthesia.

Adult↗
PubMedDate not supplied

MR blood oxygenation level-dependent signal differences in parenchymal and large draining vessels: implications for functional MR imaging.

BACKGROUND AND PURPOSE: One major limitation of current functional MR (fMR) imaging is its inability to clarify the relationship between sites of cortical neuronal activation, small parenchymal venules that are in close proximity to these sites, and large draining veins distant from the active parenchyma. We propose to use gradient-echo blood oxygenation level-dependent (BOLD) fMR time courses to differentiate large draining veins from parenchymal microvasculature. METHODS: In eight research subjects, five of whom presented with space-occupying lesions near the central sulcus, gradient-echo fMR imaging was performed during alternating periods of rest and motor activation. MR signal time courses from parenchymal regions and draining veins of different diameters, which were identified using contrast-enhanced T1-weighted scans, were evaluated. Percent signal changes (deltaS) and the time to the onset of MR signal rise (T0) were calculated. RESULTS: Mean delta(S) for all subjects was 2.3% (SD+/-0.7%) for parenchymal activation, 4.3% (SD +1.0%) for sulcal macrovasculature, and 7.3 (SD+/-1.1%) for large superficial bridging veins. The mean time to onset of MR signal increase was 4.4 seconds for parenchymal task-related hemodynamic changes and 6.6 seconds for venous hemodynamic changes, regardless of vessel size. Both the differences in delta(S) and T0 were statistically significant between venous and parenchymal activation (P < .0001). CONCLUSION: Gradient-echo fMR imaging reveals hemodynamic task-related changes regardless of vessel size and therefore might show macrovascular changes distal to the site of neuronal activity. MR-signal time-course characteristics (delta(S) and T0) can be used to differentiate between small parenchymal and larger pial draining vessels, which is especially important in presurgical planning of neurosurgical procedures involving functionally important brain regions. The knowledge about the differences in (delta)S and T0 between micro- and macrovasculature might lead to a more accurate description of the spatial distribution of underlying neuronal activity.

Adult↗
PubMedDate not supplied

Cerebral asymmetry: MR planimetry of the human planum temporale.

A method is described for the imaging and planimetric measurement of the planum temporale (PT) using computer reformations from three-dimensional fast low angle shot magnetic resonance (MR) data. The procedure allows the determination of size and left-right asymmetry of this area on the posterior supratemporal surface, which has been assumed by previous investigators to be a structural correlate of speech lateralization. To establish a consistent method for future studies, special effort was invested in the elaboration of reliable imaging criteria for the borders of the PT. The authors report MR planimetric measurements of the PT in 10 human cadaver brains performed independently and in a "blinded" fashion by two observers. A high degree of interobserver agreement was found, demonstrating the reliability of the MR criteria for PT delineation. The planimetric data correlated with those from subsequent anatomic measurements following section of the same specimens. The left-right ratios of PT size were almost the same with both methods (mean 1.9). Magnetic resonance planimetry of the PT is a noninvasive, reliable, and quantitative procedure to determine gross cerebral asymmetry in the posterior speech area.

Aged↗
PubMedDate not supplied

Rotational cerebral angiography: procedure and value.

Rotational cerebral angiography provides continuously changing projections and correspondingly excellent visualization of aneurysms or other vascular malformations requiring special or oblique views. Rotation angiography as part of the routine angiography gives a three-dimensional impression with one injection and series of films. Although additional subtraction technique is not possible and the injection time has to be prolonged, the technique is nevertheless advantageous compared with magnification angiography and angiotomography in the preoperative evaluation of cerebral vascular malformations.

Arteriovenous Fistula↗
PubMedDate not supplied

Systemic Candida albicans infection with cerebral abscess and granulomas.

This study reports the case of a 19-year-old Turkish woman who was suffering from a cerebral abscess and granuloma formation caused by Candida albicans. The diagnosis of her illness was established by cytologic analysis of the cerebrospinal fluid. Combined application of amphotericin B and 5-fluorocytosine cured the patient's disorder. Its remission was documented over a period of 2 years by the use of computed tomography.

Adult↗