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H Böhm-Jurkovic

Publications and source records attributed to H Böhm-Jurkovic.

13 recordsLinked to original sources
PubMed1999

[Digital 3D rotational angiography for the preoperative and preinterventional clarification of cerebral arterial aneurysms].

OBJECTIVE: Does the recently introduced 3D angiography provide additional information beyond standard angiography (DSA) for the diagnosis of cerebral aneurysms? METHODS: During a 3-months period DSA and 3D-angiography were performed in 40 patients harbouring a total of 49 aneurysms. Vascular regions that presented an aneurysm diagnosed by DSA were reevaluated by 3D-angiography. RESULTS: In two patients, vessel-loops previously described as aneurysms by DSA could be identified by 3D-angiography. In one patient, an aneurysm was diagnosed that could not be detected by DSA. In another case, the definitive diagnosis of an aneurysm was obtained only with 3D-angiography. In one patient, an aneurysm was diagnosed that could not be detected by DSA. In another case, the diagnosis of an aneurysm was obtained only with 3D-angiography. In two cases, aneurysms could be definitively excluded by 3D-angiography, whereas in another aneurysm a vessel originating from this lesion was identified. The size of the aneurysms measured by both methods was identical. CONCLUSIONS: Multiple projections of 3D-angiography provide a better evaluation of the anatomic situation regarding the base of the aneurysm as well as the relationship of an aneurysm to neighbouring vessels. Further, an exact differentiation between a vessel loop and an aneurysm can be made. Therefore, 3D-angiography is a valuable tool when used in conjunction with DSA.

Adult↗
PubMed1998

Virtual cisternoscopy of intracranial vessels: a novel visualization technique using virtual reality.

This paper introduces a different visualization method which we call "virtual cisternoscopy" using 3D MRA data sets. Virtual cisternoscopy uses well known tools, such as perspective volume rendering (pVR), fly-through techniques, and interactive visualization and combines them to a new approach featuring motion to resolve spatial relationships of intracranial vessels and vascular malformations. With a dedicated flight protocol extraluminal topography of intracranial arteries was analyzed using pVR. For evaluation of difficult vascular malformations extraluminal views are necessary. Therefore, movies of pVR views were produced simulating virtual tracks of neurosurgical flexible endoscopes, by flying around the intracranial vessels and vascular malformations within the cisterns. Endoluminal views were acquired additionally for precise evaluation of cases with complex vessel topography. Two healthy volunteers and three patients were examined. Comparing MIP and pVR images relevant advantages of pVR were found, such as depth information, perspective, lighting, and color. In contrast to MIP and source images of the MRA data set, virtual cisternoscopy of an aneurysm of the left middle cerebral artery demonstrated clearly an early origin of an artery in the region of the aneurysm neck/sac. In this case only virtual cisternoscopy led to the correct therapeutical decision. In a newborn, the type of a vein of Galen aneurysmal malformation could only be evaluated reliably by means of virtual cisternoscopy. The third case of a patient with a clipped aneurysm was evaluated more easily with virtual cisternoscopy than with DSA. In conclusion, virtual cisternoscopy may improve the pretherapeutic visualization of intracranial vascular malformations.

Adult↗
PubMed1998

Experiences with gadodiamide, a non-ionic contrast agent, in MRI of brain metastases.

29 patients suffering from brain metastases were studied with a single (0.1 mmol/kg body weight) and triple dose (0.3 mmol/kg) of gadodiamide, a non-ionic MR contrast agent. The study was performed using an extended imaging protocol with application of T1-weighted images in three orientations. Number of definite and suspected metastases, lesion contrast, edema delineation, and flow artefacts were evaluated. Most of the definite metastases were found in triple dose images. However, the total lesion number could only be determined by looking on all sequences as a whole. Furthermore, the number of suspected metastases could be significantly reduced with triple dose images, but once more all sequences were needed to do so. Flow artefacts were significantly increased by triple dose, whereby lesion contrast and edema delineation was considerably improved. The conclusion is that the combination of high dose application of the contrast agent and an optimized imaging protocol facilitates sufficient imaging of brain metastases. This is important for therapeutical considerations, because patients with more than 1-2 metastases will be treated primarily with radiation therapy instead of neurosurgery.

Brain Neoplasms↗
PubMed1996

A T1-weighted rapid three-dimensional gradient-echo technique (MP-RAGE) in preoperative MRI of intracranial tumours.

Our purpose was to determine the value of a T1-weighted rapid three-dimensional gradient-echo technique in preoperative MRI of brain tumours. We examined 30 patients with intracranial tumours who underwent neurosurgery, using T1-weighted magnetisation-prepared rapid gradient-echo (MP-RAGE) and axial T1-weighted spin-echo (SE) sequences, both before and after contrast medium (Gd-DTPA). Signal and contrast behaviour of anatomical and pathological structures were assessed with regions-of-interest (ROI) and visual inspection. Imaging results were compared with operative results. In 5 cases tumours and anatomical structures were segmented in MP-RAGE data sets. The MP-RAGE sequence considerably improved delineation of grey and white matter and small anatomical structures (vessels, cranial nerves), and significantly reduced flow artefacts. Contrast behaviour of tumours was similar with both techniques. Correlation of imaging with the operative results confirmed the reliability of the MP-RAGE sequence. Segmentation of MP-RAGE data sets allows three-dimensional display, which enables one to document the relevant information on a few images in selected cases.

Adolescent↗
PubMed1995

Turbo gradient-spin-echo (GRASE): first clinical experiences with a fast T2-weighted sequence in MRI of the brain.

The aim of this study was to obtain first clinical experiences with Turbo gradient-spin-echo (TGSE). This fast MRI technique is based on the GRASE sequence which combines the gradient-echo and the spin-echo technique. In 60 patients suffering from different brain pathologies, a T2-weighted TGSE sequence was compared to a conventional spin-echo sequence. Anatomical and pathological structures were evaluated visually by three independent observers; signal and contrast behavior was assessed in regions of interest. TGSE showed reduced signal-to-noise-ratios of anatomical structures except for cerebrospinal fluid. The contrast of tumors, infarctions, and hematomas was similar in both sequence types. Small microangiopathic and inflammatory lesions as well as basal ganglia degeneration presented with diminished contrast in TGSE. The TGSE sequence can already now be used to acquire T2-weighted images in additional orientations requiring extremely short measurement time. However, further improvements of image quality are necessary for routine use of TGSE.

Adolescent↗
PubMed1994

True proton density and T2-weighted turbo spin-echo sequences for routine MRI of the brain.

Our aim was to evaluate the diagnostic reliability of turbo spin-echo (TSE) sequences compared to a conventional dual-echo spin-echo (SE) sequence in routine brain MRI at 1.0 T. The following demands were made on TSE sequences: acquisition time-reduction of at least 50% and true proton density (PD) contrast (low-signal cerebrospinal fluid). A conventional spin-echo and two single-echo TSE sequences were used in 150 patients, a dual-echo TSE sequence in addition in 50 patients. Demonstration of most anatomical structures and disorders was equivalent with TSE and SE sequences. Advantages of TSE were reduced flow artefacts on T2-weighted images, better lesion contrast on PD-weighted TSE images (especially in the dual-echo sequence) and acquisition time reduction to about 5 min (single-echo TSE) and 3:35 min (dual-echo TSE). Disadvantages of TSE were: reduced contrast of iron-containing substances such as haemosiderin and of areas of calcification. By virtue of the shorter acquisition time and diagnostic reliability dual-echo TSE proved the best sequence. If it is used with only one acquisition--whereby image quality but not diagnostic reliability is slightly decreased--acquisition time can be further reduced to 1:48 min. Application of a susceptibility-sensitive gradient-echo sequence, such as FLASH, compensates for the disadvantages mentioned above.

Artifacts↗
PubMed1991

[Thrombolysis in acute occlusion of cerebral blood vessels].

Thrombolysis may achieve recanalization in cases of occlusion of the cerebral vessels. If therapy is initiated in good time, development of cerebral infarction may be at least partially prevented. Thrombolytic treatment was performed in 14 patients at the Wagner-Jauregg Hospital within a period of one year. Urokinase was given locally, while rtPA was applied locally and/or systemically. 4 patients had an occlusion of the internal carotid artery, 6 an occlusion of the middle cerebral artery, and 4 an occlusion of the basilar artery. Complete recanalization was achieved in 6 patients, partial recanalization in 4, and no recanalization in 4. The neurological outcome of the cases with complete recanalization was good with the exception of one patients who died. Partial recanalization resulted in a fair outcome in 2 patients, while the other 2 died. 3 out of the 4 patients in whom no recanalization was achieved died. Our findings show that this form of therapy may considerably improve the natural history of the disease, provided recanalization is achieved in good time. They encourage us to continue this form of therapy and to work at improving the therapeutic criteria.

Aged↗
PubMed1990

The prognostic value of somatosensory evoked potential monitoring and tumor data in supratentorial tumor removal.

The aim of this study was to find appropriate somatosensory evoked potential (SSEP) and tumor data that would predict immediate postoperative outcome. Seventeen patients were evaluated, all with supratentorial mass lesions. Intraoperative SSEP monitoring was carried out, and central conduction time, N20 amplitude, and N20 to N13 amplitude ratio were recorded throughout the operation. The differences between the end and the start of the procedure and between the end of the operation and the most substantial changes during tumor removal were calculated for statistical evaluation. Tumor location and extent were carefully determined and calculated by computed tomographic reconstructions in the axial and sagittal planes. Several tumor parameters were measured: the distances from the midpoint of the tumor to the central sulcus, midline, and base of the skull and the longitudinal and cross-sectional diameters. The electrophysiologic and tumor data sets were correlated with the immediate postoperative neurologic deterioration. For this purpose, patients were divided into two groups: group 1 = no neurologic deterioration after operation (13 patients); group 2 = neurologic deterioration after operation (4 patients). The difference in central conduction times between the end and the start of the procedure was the only variable that exhibited a significant influence on the immediate postoperative condition (P = 0.007), as determined by analysis of variance. The other electrophysiologic data as well as the tumor data failed the significance threshold of P = 0.05. Discriminant analysis was applied to test the classification capacity of the measured variables. Involving all measured variables (electrophysiologic and tumor data), discriminant analysis allowed a correct classification of all 17 patients to their proper neurologic deterioration group. Discriminant analysis for SSEP data alone led to 15 correct classifications. Tumor data, used alone for discriminating procedures, revealed 14 correct classifications. When each variable was analyzed separately, only the difference in central conduction times between the end and the start of the procedure gave significant predictions, namely, 15 correct classifications. This was the same number as achieved by all electrophysiologic variables together. No other variable could on its own yield any valid prognosis for assessment of immediate postoperative neurologic deterioration. The data confirm the importance of central conduction time recovery before the end of the operation on the patient's immediate postoperative neurologic condition.

Adult↗
PubMed1989

[Brain abscess. Prognostic factors].

Thirty-eight cases of cerebral abscess were analysed retrospectively for any factors that might influence outcome. Using the "Glasgow outcome score", age, history, level of consciousness, as well as various computed tomography findings (cisternal swelling, compression of the ventricular system, degree of oedema and size of abscess) were considered for their prognostic value. It was found that age over 40 years and clouded consciousness exerted a statistically significant unfavourable effect (P less than 0.05). Outcome was also unfavourable in half the patients with multiple abscesses, but the number of cases (six) was too small to be statistically significant. All other variables had no statistically significant influence on prognosis.

Adolescent↗
PubMed1986

[The value of early postoperative CT study after lumbar intervertebral disk surgery].

The changes of the early intraspinal conditions few days after an operation of a lumbar disc herniation are little known. We, therefore, examined these operation areas by CT on a representative group of 256 patients. Besides the "common" findings, such as seroma, one must classify conditions such as haematomas, isolated bone fragments and/or residual disc tissue as "unusual" changes. The CT findings are correlated with clinical symptoms. We conducted CT and clinical follow-up studies in 91 patients several weeks later. All patients showed epidural scars of very different intensity. The comparison between early postoperative findings and the controls documents the high accuracy of the interpretation of the early postoperative states seen by CT. Therefore, it is possible to give hints for the indication for early postoperative CT examinations, for the prognosis as well as for the technique for a safe operative procedure.

Female↗
PubMed1981

[The value of compute tomography in "sciatica" (author's transl)].

13 cases of therapy-resistant lumboischialgia without herniated disk, caused in 12 cases by a tumour and in 1 case by an abscess, were examined by computed tomography of the lumbar and pelvic region. This method is indicated immediately after insufficient results of conventional X-ray methods (including tomography) and of lumbosacral radiculography. The compute tomography is indispensable also in patients with "sciatica" with a known malignoma. The informations given by computed tomography are essential for the therapy planning.

Adenocarcinoma↗
PubMedDate not supplied

MR diagnosis of vein of Galen aneurysmal malformations using virtual cisternoscopy.

Vein of Galen aneurysmal malformations (VGAMs) are rarely seen intracranial congenital vascular malformations with extremely complex vascular architectures. We present two newborns with an unclear intracranial mass being discovered in routine intrauterine ultrasonography. Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) identified these lesions as VGAMs. Besides conventional MRA analysis, "virtual cisternoscopy"-a special kind of virtual endoscopy combining perspective volume rendering and motion-was applied to assess the intracranial vasculature. One newborn was treated by means of interventional neuroradiology with coiling of the median prosencephalic vein. The clinical outcome in this case was excellent. The other will undergo interventional therapy shortly.

Cerebral Veins↗