Gábor Bajzik

In the present study, we report procedural and mid-term functional outcome data on the first 50 neurointerventional treatments of acute ischemic stroke in the Kaposi Mór County Hospital, Kaposvár, Hungary. Endovascular recanalization of occluded large cervical and intracranial arteries was performed following an unsuccessful intravenous lysis or when intravenous lysis was contraindicated. A control cohort was retrospectively formed by analyzing data of 16 patients who has been unsuccesfully treated with iv. lysis before neurointervention was available in our hospital. Recanalization rate was 84% and major complication rate was 2% in the neurointerventional group. Mid-term good functional outcome, defined as mRS 0-2, was achieved in 44% in the neurointerventional and in 13% in the intravenous lysis group, after 11.5 and 39.7 months follow-up period, respectively. Subgroup analysis revealed patient age as the strongest predictive factor of good functional outcome. Our data shows that neurointerventional treatment of acute ischemic stroke gives substantially improved functional outcome, in accordance with the results of the recently published international randomized trials.

Background: Lung cancer is the most common fatal malignacy and also the primary cause of cancer mortality. Participation in lung screening is an important step in diagnosing patient in early stage and it can promise better outcomes. The aim of this preliminary study was to determinate the differences in the participation rate of smokers and non-smokers in lung cancer screening and to determine the communication strategies to increase the participation rate. Methods: In the given period of time (from May to August 2012) out of 1426 people who participated in the lung screening program 1,060 adult volunteers (331 males and 729 females, average age 54.0±9.3 years), completed fully and anonymously author’s questionnaire that contained 28 questions. 25.7% of the respondents were smokers (n=272), 64.6% have never smoked, while 9.7% were former smokers. Results: Mostly former smokers considered lung screening as an effective method for early detection of pulmonary diseases (86.4%). The most important source (41.0%) of information was the general practitioner. The participation rate of non-smokers is higher in lung screening than the ratio of non-smokers in the population. The unclear data suggest that smokers need distinct, concise messages to know why they should regularly undergo lung screening and doctors have a major role in this. Conclusions: We found that smokers significantly more frequently took part in lung screening annually. It is positive that the participation rate of former smokers is higher than non-smokers, it is just a bit lower than the participation rate of smokers—both in annual and biannual participation. The participation rate of non-smokers is higher in lung screening than the rate of non-smokers in the population.

Application of a quantitative MR-spectroscopic method for 3T clinical scanners based on tissue water content as an internal reference. Six (22 +/- 2 yrs) volunteers were involved in the study. We performed T1 relaxation time measurements in a particular slice of the brain at 1T and 3T. Based on the validated water content measurement at 1T, the correlation of relaxation time T1 and water content was determined at 3T. The resulting water content served as internal reference for the quantification of localizated MR-spectroscopic measurement. At 3T our method resulted in 37.6 +/- 0.5 mol/l and 46.4 +/- 1.5 mol/l tissue water content in the white and gray matter, respectively. Calibration based on water content led to following metabolite concentrations: N-acetyl-aspartate 7.79 +/- 0.67 mmol/l; creatine 3.76 +/- 0.28 mmol/l; choline 3.68 +/- 0.47 mmol/l; myo-inositol 10.35 +/- 3.70 mmol/l in the white matter; and N-acetyl-aspartate 8.20 +/- 0.45 mmol/l; creatine 4.76 +/- 0.18 mmol/l; choline 2.64 +/- 0.35 mmol/l; myo-inositol 8.32 +/- 1.42 mmol/l in the grey matter. Tissue water content based on T value at 3T shows good accordance with gravimetric or other MR methods in the literature. Using it as an internal reference resulted in white matter metabolite concentrations that are in the range of previously published data. Comparing metabolite values of grey matter is more difficult because data in the literature substantially differ. The presented method is simple and easily applicable on any MR scanner without complicated correction and calibration steps.

Purpose: To provide a straightforward method for metabolite quantitation in the brain. Tissue water concentration can be determined in a voxel by measuring T₁ and it may provide an internal reference for the calculation of the metabolite concentrations.Materials and Methods: Water‐suppressed stimulated echo acquisition mode spectra were obtained at 1.5T, and the tissue water content was calculated from T₁.Results: The calculated water content values demonstrated very good agreement with literature data. Metabolite concentrations (mmol/liter) in the gray and white matter: N‐acetyl‐aspartate = 14.02 ± 1.93, creatine = 9.98 ± 1.03, and choline = 1.14 ± 0.24; N‐acetyl‐aspartate = 11.08 ± 2.24, creatine = 7.83 ± 0.66, and choline = 2.05 ± 0.38, respectively.Conclusion: The water content calculated from T₁ can yield an internal reference in MR spectroscopy, and the accurate measurement of metabolite concentrations is feasible. The proposed method is simple and can readily be applied in any MR center without the need for complicated corrections or calibration procedures. J. Magn. Reson. Imaging 2008;28:34–38.

The aim of the study was to compare the utility and effectivity of conventional and virtual bronchoscopy in the follow up of patients with main airway stenosis. 23 patients with trachea or main bronchi stenosis were enrolled in the study. The causes of the stenosis were malignant or benign tumor, struma and stent. The stenoses were evaluated before and after the different interventions (i.e. mechanical dilatation, laser photocoagulation, stent implantation, radiotherapy, chemotherapy or surgical resection.) The mean time between the first and second endoscopic and virtual bronchoscopic examinations was 140 days. The authors found good correlation between bronchofiberoscopy and virtual bronchoscopy findings. The data of virtual bronchoscopy were more exact. Based on this study the virtual bronchocopy can replace the traditional invasive method to follow-up patients with main airway stenosis.

The optimal therapy of brain stem tumours of different histopathology determines the expected length of survival. Authors report 125Iodine interstitial irradiation of brain stem tumours with stereotactic brachytherapy. Two patients having brain stem tumours were suffering from glioma or from metastases of a carcinoma. In Case 1 the tumour volume was 1.98 cm3 at the time of planning interstitial irradiation. The control MRI examination performed at 42 months post-op showed a postirradiation cyst size of 5.73 cm3 indicating 65.5% shrinkage. In Case 2 the shrinkage was more apparent as the tumour volume measured on the control MRI at 8 months post-op was only 0.16 cm3 indicating 97.4% shrinkage of the 6.05 cm3 target volume at the time of brachytherapy with the metastasis practically disappearing. Quick access to histopathological results of the stereotactic intraoperative biopsy made it possible to carry out the 125Iodine stereotactic brachytherapy immediately after the biopsy, resulting in less inconvenience for patients of a second possible intervention. The control MRI scans show significant shrinkage of tumours in both patients. The procedure can be performed as a biopsy. The CT and image fusion guided 125Iodine stereotactic brachytherapy can be well planned dosimetrically and is surgically precise.

Three-dimensional contrast enhanced magnetic resonance angiography (3D CE MRA) is an increasingly important tool in modern noninvasive vascular imaging. MR angiography has rapidly advanced in the past few years making vascular imaging throughout the body safer and more accurate. The authors analyse the diagnostic and clinical value of the method based on their own experience and guidelines given by the literature. This article describes the basic technical principles of 3D CE MRA, and gives a short overview of the usefulness of this technique investigating vascular diseases. Between August 17, 1999 and September 28, 2001 the authors performed eighty nine contrast-enhanced MR angiography with a 1.5 T scanner. Contrast material was administered intravenuosly with a power injector. The most frequent examinations included imaging of the aorta, supraaortic and renal arteries. 82 technically successful angiography was performed. The images could not be evaluated due to poor quality in 5 cases and failure in 2 cases. MR angiographic images provided adequate spatial resolution within single breathhold. The time-of-flight and phase contrast MR angiographic techniques have been replaced in most vascular territories by the contrast-enhanced method. With future technical developments greater spatial and temporal resolution will become possible, thus increasing the usefulness of 3D CE MR angiography. In the near future this method of imaging will become the method of choice in the investigation of the arterial system, and in some special cases of the venous system.

Searching for metastases of medullary thyroid cancer (MTC), FDG PET was applied. PET results were compared with those of conventional diagnostic imaging procedures. After primary treatment, 52 MTC patients with elevated serum tumor marker levels and/or general symptoms (diarrhoea/flush) underwent radiological (CT/MRI), 131-iodine labeled metaiodo-benzylguanidine (MIBG) whole-body scintigraphy and FDG PET investigations. At least one pathological lesion was detected in 49 patients by PET, 35 by CT, 32 by MRI and 3 by MIBG. FDG PET was far superior to the other methods in identifying metastases in the supradiaphragmatic lymphatic regions. In the follow-up of MTC patients, FDG PET was more sensitive in localizing tumorous LN involvement, especially in the cervical, supraclavicular and mediastinal lymphatic regions, compared to other imaging modalities.

Postsurgically elevated or increasing serum calcitonin levels strongly suggest the presence of residual or recurrent medullary thyroid carcinoma (MTC). Several imaging modalities (sonography, MRI, CT, scintigraphy with different types of radiolabeled ligands, etc.) are routinely used in an attempt to localize tumorous tissue, but such efforts often fail. In the search for a more reliable method, 18F-FDG PET was applied to detect tumor tissue of residual or recurrent MTC. Forty patients with a postoperatively elevated plasma calcitonin level were included. These patients underwent routine diagnostic imaging procedures (CT, MRI, and 131I-metaiodobenzylguanidine [MIBG] whole-body planar scintigraphy or SPECT) and 18F-FDG PET examinations. Two independent experts visually analyzed the images provided by each method to detect pathologic lesions. Lymph nodes of > or = 1 cm in short diameter that were detected by radiologic methods were considered to be pathologic. 18F-FDG accumulation with a sharp contour reported by both independent observers was similarly regarded as pathologic. PET detected 270 foci with a high tracer accumulation, whereas only 116 lesions were detected by MRI and 141 by CT. The numbers of such foci determined by PET, MRI, and CT were 98, 34, and 34, respectively, in the neck; 25, 5, and 6, respectively, in the supraclavicular regions; and 117, 35, and 39, respectively, in the mediastinum. 131I-MIBG scintigraphy findings were positive for only 3 patients. For MTC patients with a postoperatively elevated plasma tumor marker level, PET was more sensitive and superior in localizing tumorous lymph node involvement than were the other imaging modalities, especially in the cervical, supraclavicular, and mediastinal lymphatic regions.