Biomedical subjects

G Bajzik

Publications and source records attributed to G Bajzik.

8 recordsLinked to original sources

PubMed2001

Angiography effectively supports the diagnosis of hepatic metastases in medullary thyroid carcinoma.

BACKGROUND: Medullary thyroid carcinoma (MTC) belongs in the group of neuroendocrine tumors with early lymphatic and hepatic dissemination. A high rate of undetectable metastases is hypothesized to be responsible for the frequent mismatch between the apparent relatively small tumor burden and the elevated plasma tumor marker level. METHODS: Thirty-six MTC patients with residual/recurrent biochemical signs (elevated basal calcitonin level) and/or characteristic general symptoms (diarrhea and/or flushing) were systematically examined by conventional radiology, whole-body 18F-deoxyglucose positron emission tomography (PET), dynamic liver computed tomography and magnetic resonance imaging, and hepatic angiography. RESULTS: Conventional diagnostic imaging revealed lymph node (LN) involvement in the cervical, mediastinal, supraclavicular, and axillary regions (16 cases), and multiple pulmonary (3 cases), bony (1 solitary and 1 multiple case), and breast (1 case) metastases. (18)F-deoxyglucose PET identified all these extralymphatic metastatic lesions (except 2 cases with multiple pulmonary metastases), and also supradiaphragmatic LN involvement in 34 (94%) patients. In 32 (89%) cases, multiple small (generally < or = 1 cm) hypervascular, hepatic metastases undetectable by other imaging methods were localized angiographically. Of the 23 original pathologic specimens investigated, 18 (78%) exhibited LN involvement. The smallest primary tumor in patients with hepatic metastases was 1 cm. CONCLUSIONS: Hepatic angiography is recommended for primary staging in MTC patients with a primary tumor measuring 1 cm or larger, and/or pathologically proven LN involvement, and also during restaging for suspected recurrences to avoid unnecessary extensive surgical LN dissection in the neck and mediastinum.

Adult↗

PubMed2001

[Virtual bronchoscopy: a new non-invasive diagnostic method in pulmonology].

Virtual reality (3 dimensional modelling of the human body) has developed as a convergence of advancing digital imaging modalities and computer graphics technologies. With this method endoscopic simulations of cavitary organs are feasible. Virtual bronchoscopy was initially described in 1993. The authors selected patient with previously detected stenosis of the trachea or the main bronchi with bronchofiberscope. They performed targeted, thin-slice helical computer tomography of the lesions. These data were transferred to a workstation and the virtual endoscopic models of the airways were generated using dedicated software. Based on cases the authors describe their preliminary experience with the method. The findings were compared with those of bronchofiberscopy. Analyzing these results and the literature the potential clinical applications of virtual bronchoscopy are discussed.

Adult↗

PubMed2001

Normal brain and brain tumor: multicomponent apparent diffusion coefficient line scan imaging.

Magnetic resonance line scan diffusion imaging of the brain, with diffusion weighting between 5 and 5,000 sec/mm(2), was performed in healthy subjects and patients with a 1.5-T machine. For each voxel, biexponential signal decay fits produced two apparent diffusion constants and respective signal amplitudes. Images based on these parameters show potential for use in the differentiation of gray and white matter, edema, and tumor.

Brain↗

PubMed2001

ECG-gated dynamic magnetic resonance imaging method for examination of the pig heart.

A dynamic magnetic resonance imaging (MRI) method was developed for in vivo examination of the pig heart. Measurements were carried out on 15 meat-type pigs of different liveweight using a 1.5 T equipment. Inhalation anaesthesia was applied, then data acquisition was synchronised by ECG gating. Depending on the heart rate and heart size, in each case 8 to 10 slices and in each slice 8 to 14 phases were acquired prospectively according to one heart cycle. During the post-processing of the images the left and the right ventricular volumes were determined. The values measured at 106 kg liveweight are 2.5 times higher than those obtained at 22 kg, while the ejection fractions are equal. The calculated cardiac output values were 3.5 l (22 kg, 132 beats/min.), and 6.0 l (106 kg, 91 beats/min.), respectively. After measuring the wall thickness, the contraction values were also determined for the septum (70%), and for the anterior (61%), posterior (41%) and lateral (54%) walls of the left ventricle. Three-dimensional animated models of the ventricles were constructed. Based on the investigations performed, the preconditioning, the anaesthetic procedure, the specific details of ECG measurement and the correct MR imaging technique were worked out.

Animals↗

PubMed2000

[MR-guided diagnostic and therapeutic interventions. Review and own preliminary experience].

Magnetic resonance (MR) guided diagnostic and therapeutic interventions are relatively new methods in the larger field of radiologic interventions. Good spatial resolution and soft tissue characterisation, multiplanar imaging capability, functional imaging and up-to-date computer systems enable MR imaging to guide a wide range of interventional procedures. Biopsies, punctures and drainages of fluid collections, tumor ablations and vascular interventions can be performed with the help of MRI. MR imaging provides an unique opportunity for planning, guiding and monitoring certain types of intraoperative procedures. The authors outline the basic features of MR intervention and report their own initial experience in interventional procedures in 8 cases for the first time in Hungary.

Abscess↗

PubMed1999

The position of spiral CT in the complex diagnostics system for pulmonary embolism.

The development of CT technology, the more widespread use of spiral CT and the application of contrast injection techniques now enable such levels of contrast intensity in the segmental and larger pulmonary arteries to be attained as to allow the minimally invasive, direct detection of emboli. This technique has a role to play in the strategy for check-up examinations for pulmonary embolism. By providing a realistic alternative the spiral CT examination serves to reduce the number of scintigraphy examinations to be performed. At the same time, the role played by invasive pulmonary angiography examinations is now shifting towards intervention.

Aged↗

PubMed1998

[Magnetic resonance cholangiography: our first experience].

Magnetic resonance cholangiography is a new field of clinical application within MR imaging, enabling high-quality imaging on disorders of the pancreaticobiliary system. This cross-sectional imaging technique is, by means of postprocessing, suitable for the production of reconstruction images appropriate for comparison with endoscopic retrograde cholangiography. The quality of the images thus obtained is dependent upon the level of development of the technology and software available. Observations arising from authors initial examinations using 2D fast spin echo sequence are summarised.

Biliary Tract Diseases↗

PubMed1997

[Method and use of intracranial cine MR imaging].

The authors introduce a dynamic, non-invasive MR method for the examination of liquorspaces and liquor flow in 221 patients. This method is suitable not only for a dynamic imaging of liquor-flow but also for the semi-quantitative evaluation of flow through the aqueduct. This later measurement can help to select the shuntresponsive NPH cases as well. Cine MR examination along with the routine protocol seems to be most helpful in the differential-diagnostics of different hydrocephalus cases.

Humans↗