Biomedical subjects

L Csiba

Publications and source records attributed to L Csiba.

At least 37 records · Page 2Linked to original sources

PubMed2000

Collateral configuration of the circle of Willis: transcranial color-coded duplex ultrasonography and comparison with postmortem anatomy.

BACKGROUND AND PURPOSE: The anterior communicating artery (AcoA) and posterior communicating arteries (PcoA) of the circle of Willis provide the main route for collateral blood flow in cases of carotid artery obstruction. Transcranial color-coded duplex ultrasonography (TCCD) allows real-time measurement of the collateral function of the AcoA and PcoA. The primary objective of this study was to determine the collateral artery threshold diameters for supplying collateral flow. METHODS: In 12 acute stroke patients with a median age of 75 years (51 to 91 years), the collateral integrity of the circle of Willis as assessed by TCCD and carotid compression tests was compared with their postmortem anatomy. The lengths and diameters of the collateral arteries were measured. RESULTS: TCCD demonstrated absent anterior collateral flow in 3 patients. In 1 of these patients, absence of anterior cross-flow was due to an occluded anterior cerebral artery, which was revealed at autopsy. Absent posterior collateral flow was found in 14 hemispheres. In 2 of these hemispheres, autopsy revealed a fetal configuration of the posterior cerebral artery hampering posterior collateral flow. The median (range) diameters as found at autopsy of the functional (n=19) and nonfunctional (n=16) collateral arteries of the circle of Willis were 1.1 (0.4 to 2.0) and 0.5 (0.3 to 0.7) mm, respectively (P=0.003). PcoA diameters were found to correlate negatively (rho=-0. 50, P=0.01) to the diameters of their accessory P1 segments. CONCLUSIONS: The threshold diameter allowing for cross-flow through the primary collateral arteries of the circle of Willis is between 0. 4 and 0.6 mm.

Adult↗

PubMed1999

[Autoradiography of neurotransmitter receptors in whole human brain hemisphere sections].

Autoradiography is one of our most important tools to gain knowledge about neurotransmitter-receptors playing a key-role in information transmission between neurons. Autoradiography, in its most sophisticated form, is performed on whole human hemispheric sections. The main objective of the authors is to present this application of autoradiography. This in vitro method produces images with high spatial resolution that enable us to qualitatively and quantitatively characterize the regional distribution of the receptors under study. With this technique both the different receptor systems in various physiological and pathological conditions of the brain and the pharmacological parameters of the radioligand, itself, used for a given investigation can be analysed. As a consequence, the results of autoradiography can be successfully used in drug development and trial, brain research and, indirectly, in the every day practice of physicians (diagnosis, differentialdiagnosis, therapy). Autoradiography plays an important role in the validation of in vivo techniques (positron emission tomography, single photon emission tomography) and results in a more complex (in vivo and in vitro) insight into the neurochemical organisation of the brain.

Autoradiography↗

PubMed1999

[Carotid atherosclerotic lesions in stroke patients with diabetes mellitus].

The aim of the study was to assess the incidence of atherosclerotic lesions on carotid arteries among diabetic subjects suffering from cerebrovascular accident. A further aim was to investigate the relationship between the severity of the carotid lesion, the stroke subtype and the fatal outcome. One hundred and sixty eight patients treated because of cerebrovascular accident at the Dept. of Neurology University Medical School of Debrecen were studied. The age of the patients, the duration of diabetes and hypertension were registrated. Base on duplex scanning carotid lesions were divided in 6 groups of severity (normal, intimal sclerosis, slight, moderately severe, severe stenosis and occlusion). Based on clinical signs and CT results stroke subtypes were divided into five groups (lacunar and non-lacunar infarctions, hemorrhages, normal CT and others). The relationship between severity of carotid lesions, stroke subtype and lethal outcome was assessed using statistical tests. Carotid stenosis of different severity was detected in 60% of the cases. Severity of stenosis was independent from duration of diabetes, but it was positively related to duration of hypertension (p = 0.016). In 1/3 of the patients lacunar strokes, in another 1/3 non-lacunar strokes were observed. No significant relationship was found between severity of carotid stenosis, stroke subtype and lethal outcome of the patients (p = 0.53 and p = 0.26 respectively). Diabetic patients suffering from stroke have a higher incidence of carotid artery atherosclerotic lesions than diabetics without stroke. A special attention should be paid to the carotid duplex sonography in order to detect diabetic cerebral macroangiopathies in early, asymptomatic stage.

Aged↗

PubMed1999

No relationship between cerebral blood flow velocity and cerebrovascular reserve capacity and contemporaneously measured glucose and insulin concentrations in diabetes mellitus.

Blood glucose and insulin concentrations have been reported to influence cerebral hemodynamics. We studied the relationship between actual blood glucose and insulin concentrations and resting cerebral blood flow velocity in the middle cerebral artery and cerebrovascular reserve capacity after acetazolamide stimulation. Thirty-six insulin-dependent diabetic patients in a state of good glycemic control were studied. Blood samples were taken for determination of glucose and insulin concentrations. Subsequently we measured resting cerebral blood flow velocities in supine position using transcranial Doppler, administered 1 g acetazolamide intravenously, and repeated the measurements after 5, 10, 15 and 20 minutes. Cerebrovascular reserve was calculated as the maximal percent increase after acetazolamide stimulation. Multiple regression was used for statistical analysis. Blood glucose levels were not correlated with resting blood flow velocity (R = 0.21, p = 0.22) nor cerebrovascular reserve capacity (R = 0.17, p = 0.32). Similarly, no correlation was found between insulin concentrations, resting cerebral blood flow velocity (R = 0.24, p = 0.22) and cerebrovascular reserve (R = 0.26, p = 0.24). Studying patients with long-term (> 10 years) and short-term (</= 10 years) disease duration yielded the same lack of correlation. We conclude that there is no significant correlation between contemporaneously measured glucose and insulin concentrations and either cerebral blood flow velocity or cerebrovascular reserve capacity in the middle cerebral artery in type 1 diabetic patients with good control.

Acetazolamide↗

PubMed1999

Basic characteristics of hospital stroke services in Eastern Hungary.

Stroke mortality is extremely high in Central-Eastern European countries. We report basic characteristics of a stroke unit in Eastern Hungary, including age and sex distribution; the proportion of transient ischemic attacks (TIA), ischemic and hemorrhagic strokes; case fatality; application of diagnostic methods; and length of stay for all patients treated with acute cerebrovascular disease over a 12-month period. Records of all patients with acute cerebrovascular disease (n = 522) discharged in 1995 from a stroke unit with a well defined catchment area of 220,000 inhabitants in Eastern Hungary were retrospectively analyzed. Case fatality was 18.6% for all patients and 21.1% after excluding cases with TIA. Computer tomography, duplex carotid ultrasound, cerebrospinal fluid examination and electroencephalography were performed in 79%, 77%, 7% and 2% of the patients, respectively. The database of the university hospital with the same catchment area was electronically searched for patients who were discharged with the diagnosis of stroke from the three departments of internal medicine. Stroke mortality data of the catchment area based on death certificates was obtained from the Central Statistical Bureau. Two hundred twenty-eight stroke deaths were reported in the catchment area in 1995. In the same period 97 stroke deaths occurred at the stroke unit and 76 at the departments of internal medicine. If we aim to treat all patients with acute stroke at the stroke unit, with the present stroke incidence and duration of hospital stay the current capacity of the stroke unit (1 bed per 10.000 inhabitants) should be doubled.

Adult↗

PubMed1999

Screening of vascular cognitive impairment on a Hungarian cohort.

Cerebrovascular disease is a major public health problem in Eastern European countries. A Hungarian post-stroke population was examined to estimate the rate of dementia, the risk factors for cognitive impairment, and the applicability of a recently established Canadian diagnostic checklist in this cohort. Chronic cerebrovascular outpatients were screened for cognitive impairment with a combined checklist: the Diagnostic Checklist for Vascular Dementia established by the Consortium of Canadian Centres for Clinical Cognitive Research using the Mini Mental State Examination instead of the detailed neuropsychological part of the Checklist. Of the 247 consecutive patients at a cerebrovascular outpatient unit, 176 had cerebrovascular disorder diagnosed either by computed tomography (CT; n=126) or by the clinical signs. Of these, 15% were cognitively impaired and 5% fulfilled the criteria of dementia. The mean age of the patients with cognitive impairment was significantly higher than that of patients with normal cognition (68.2+/-10.2 and 60.5+/-10.5 years, P<0.001). The Barthel index was significantly lower in the cognitively affected group than in non-affected patients (92.4+/-16.0 and 97.1+/-8.7, P=0.027). Diabetes and more than two subcortical infarcts on CT or magnetic resonance imaging were more frequent in patients with cognitive loss (P=0.043 and P=0.013, respectively). Cognitive performance was also influenced by the level of education. Higher age, diabetes, motor deficits, and multiple subcortical infarcts are risk factors for cognitive impairment after stroke. The combined checklist appears to be a practical screening test for cognitive impairment in patients with chronic cerebrovascular diseases.

Age Distribution↗

PubMed1999

Screening for depressive symptoms among post-stroke outpatients in Eastern Hungary.

Patients were consecutively enrolled in a cross-sectional study to determine the severity of depressive symptoms and the rate of treated depression in a patient population returning to a stroke outpatient service during a 10-week period for a regular check-up examination after their stroke. Of the 143 stroke patients, 119 fulfilled the inclusion criteria. The 13-item Beck Depression Inventory was used to screen for depressive symptoms. The score was at least 5 in 53%, 10 or above in 26%, and 15 or above in 11% of patients. Severity of depressive symptoms did not depend on gender, age, time elapsed from stroke, or the site of the cerebral lesion. Most patients with considerable depressive symptoms did not receive antidepressant medication at the time of the screening.

Adult↗

PubMed1998

[Hemostatic abnormalities in ischemic stroke].

The authors studied whether haemostatic abnormalities connected with the development of cerebral circulatory disturbances can be demonstrated in young stroke patients in whom Doppler and angiographic examination failed to reveal deviations indicative of stroke. They determined the in vivo activation of the coagulation system (TAT, F 1 + 2), the degree of secondary fibrinolysis (D-dimer), the plasma levels of the markers of fibrinolysis, with special regard to inhibitors: plasminogen activator inhibitor (PAI-1), alpha 2 antiplasmin (alpha 2 AP), alpha 2 macroglobulin (alpha 2 M), the frequency of pathologic serum lipoprotein (a)-Lp(a)-values and the association of PAI-1 and Lp(a) with the fibrinolytic system. They conclude that in the acute phase of the disease, the TAT and F 1 + 2 values were significantly elevated compared to the control, without change in the D-dimer value. The results suggest that in the tested period increased thrombin generation dominated and it significantly surpassed plasmin activity since the D-dimer values of that period did not indicate substantial increase in secondary fibrinolysis. The results of the study were separately analyzed in acute, chronic TIA and stroke groups. In the TIA and acute group the F 1 + 2 values, while in stroke the TAT values were more elevated. The in vitro fibrinolytic capacity of the patients significantly decreased compared to controls, showing significant correlation with the Lp(a) level, but not with the PAI value. Examination of the marker molecules renders possible to assess the degree of hypercoaguability and of endogenous lysis. Their knowledge is held important for judging the progression of the disease and the therapeutic consequences.

Adult↗

PubMed1998

[Cerebrovascular reactivity in non-insulin dependent diabetes mellitus (preliminary results)].

AIMS: Previously numerous investigators reported about impairment of cerebrovascular reserve capacity in Type I, diabetes mellitus. However, no similar data are available about patients suffering from Type II diabetes. The goal of the study was to assess cerebrovascular reserve in Type II diabetic patients. PATIENTS AND METHODS: 14 NIDDM patients and 20 healthy controls were studied. Middle cerebral artery mean blood flow velocity was measured at rest and during 20 minutes after i.v. administration of 1 g. acetazolamide. Velocities measured after acetazolamide were compared to resting values and were expressed as the percent increase of the mean velocity. Data obtained in diabetics and healthy persons were compared using Student's t-test. The correlation between age of the patients, diabetes duration, actual blood glucose-, insulin-, glycosylated hemoglobin-, urine microalbumin concentrations and resting blood flow velocity and cerebrovascular reserve capacity was assessed using linear regression analysis. RESULTS: Resting cerebral blood flow velocities, cerebrovascular reactivity and reserve capacity did not differ from that of healthy controls. No correlation has been found between obtained laboratory parameters and resting cerebral blood flow velocities and cerebrovascular reserve capacity. CONCLUSIONS: Vasodilatory ability of the cerebral arterioles in NIDDM-patients did not differ from that of healthy control persons. Further studies are needed to find out an accurate screening method for detection of cerebral microangiopathic changes in Type II diabetes mellitus.

Acetazolamide↗

PubMed1998

[Assessment of cerebrovascular reactivity in patients with symptomatic and asymptomatic atherosclerotic carotid artery lesions].

AIMS: Strokes caused by hemodynamically significant internal carotid artery stenoses and occlusions are believed to be embolic or hemodynamic of origin. The aim of the study was to assess cerebral hemodynamic compromises of significant carotid artery stenosis of occlusion using vasodilatory testing (acetazolamide test) in asymptomatic and symptomatic patients. PATIENTS AND METHODS: 36 patients with unilateral, hemodynamically significant carotid stenosis were investigated using transcranial Doppler acetazolamide-test. There were 12 asymptomatic and 24 symptomatic patients. The middle cerebral artery mean blood flow velocity was measured at rest and after intravenous injection of 1 g acetazolamide. The absolute mean blood flow velocities and the cerebrovascular reactivity was compared at the stenotic and non-stenotic side. In a further analysis the mean velocities and the cerebrovascular reactivity values of the stenotic side were compared. Results of acetazolamide test performed on 28 healthy volunteers were used as control values. RESULTS: There were no side-differences between the middle cerebral artery mean blood flow velocity and cerebrovascular reactivity values in the asymptomatic group. In the symptomatic group, however middle cerebral artery mean velocity and cerebrovascular reactivity after acetazolamide was significantly lower on the stenotic side, than on the non-stenotic one. Comparing the different groups non-stenotic sides did not differ to each other in their cerebral blood flow velocity and cerebrovascular reactivity. In the symptomatic patients, however, cerebral blood flow velocity and cerebrovascular reserve capacity after acetazolamide was lower, than that of the stenotic side of asymptomatic patients and controls. CONCLUSIONS: The transcranial Doppler is a suitable method for detecting altered cerebral hemodynamics in significant carotid stenosis. Impaired cerebrovascular reactivity may refer to the impairment of cerebral autoregulatory mechanisms.

Acetazolamide↗

PubMed1998

Cerebral effects of a single dose of intravenous vinpocetine in chronic stroke patients: a PET study.

The effects of vinpocetine (Cavinton) on the cerebral glucose metabolism of chronic stroke patients are studied with positron emission tomography. The regional and global cerebral metabolic rates of glucose (CMRglu) and the kinetic constants related to them are quantified before and after single-dose intravenous vinpocetine treatment. These measurements are completed with transcranial Doppler sonography and single photon emission computed tomography to explore the possible mechanisms underlying the resulting changes in glucose uptake and metabolism in the brain. The authors' findings indicate that a single-dose vinpocetine treatment, although it does not affect significantly the regional or global metabolic rates of glucose, improves significantly the transport of glucose (both uptake and release) through the blood-brain barrier in the whole brain, the entire contralateral hemisphere, and in the brain tissue around the infarct area of the symptomatic hemisphere. These changes are in accord with increased blood flow in the entire contralateral hemisphere as well as decreased blood flow velocity and increased peripheral vessel resistance in the entire symptomatic hemisphere.

Aged↗

PubMed1997

[Cerebral positron emission tomographic study in systemic lupus erythematosus].

The cerebral glucose metabolism in eight patients with systemic lupus erythematosus (SLE) and in five healthy controls were examined by positron emission tomography (PET) using 18-F-labeled deoxy-glucose (FDG) as tracer. One of the eight patients had no abnormality by magnetic resonance imaging (MRI), three of them had cerebral atrophy and four patients had multiple white matter hyperintensities and vascular infarcts in the striatum as assessed by MRI. With FDG-PET, inhomogeneous multifocal cerebral glucose hypometabolism was detected, more frequently in the temporal lobe of right hemisphere. The PET findings did not correlate always with the neurological symptoms. Abnormalities in brain metabolism can be detected more frequently by PET, than morphological changes by MRI, indicating the involvement of the central nervous system.

Adult↗

PubMed1997

[First Hungarian experiences with positron emission tomography (PET) studies. Members of the PET working group].

Diagnostic investigations commenced on the 28th of June 1994 in Hungary's and Central Europe's first PET Centre at the University Medical School of Debrecen. The Centre is equipped with a GE 4096 Plus whole body PET scanner. A metabolic tracer, 18F-deoxy-D-glucose (FDG), was used in the investigations. During the first 15 months 249 PET investigations were made in the Centre of which 242 were diagnostic and 7 normal subjects served as control for the patient studies with brain scans. The number of oncological indications (intra- and extracranial tumours, Hodgkin's lymphomas) was n = 105 (43.4% of the 242 diagnostic examinations), neurological investigations (without intracranial tumours) formed the dominant group (n = 117; 48.3%), whereas the number of cardiological indications was 20 (8.3%). The oncological studies included those of intracranial tumours (n = 76; 31.4%); thyroid tumours (n = 9; 3.7%); Hodgkin's lymphomas (n = 7; 2.9%) and other extracranial tumours (n = 13; 5.4%). The distribution of different neurological and psychiatric investigations was as follows: localization of focal epileptogen zone (n = 60; 24.8%); differential diagnosis of dementias (n = 30; 12.4%); exploration of cerebrovascular diseases (n = 10; 4.1%); and other neurological diseases (n = 17; 7.0%). The main objective of the cardiological PET investigations was the exploration of viable myocardium. The present paper overviews both the procedures (including administrative issues, as well) and the results of the first 249 FDG-PET investigations.

Aged↗

PubMed1997

Cerebrovascular reactivity in hypertensive patients: a transcranial Doppler study.

PURPOSE: We studied the usefulness of transcranial Doppler sonography for assessing changes in vasoreactivity in patients with hypertension and the hemodynamic consequences of hypertension. METHODS: The study group comprised 25 patients with chronic severe hypertension and 25 age- and sex-matched healthy subjects. Cerebrovascular reserve capacity was assessed by transcranial Doppler recording of the blood flow velocity in both middle cerebral arteries before and 5, 10, 15, and 20 minutes after intravenous injection of 1 g of acetazolamide (Diamox). Blood pressure, blood gases, and other blood parameters were also measured before and after acetazolamide injection. The sizes of the left atrium, left ventricle, and aortic root were measured by echocardiography and correlated with the vasoreactivity after acetazolamide injection. RESULTS: After acetazolamide injection, no significant changes in blood pressure were observed in either group. The mean blood flow velocity in the middle cerebral arteries of hypertensive patients (60.8 +/- 2.6 cm/sec) was not significantly different from that of controls (58.8 +/- 1.9 cm/sec) before acetazolamide injection. Ten minutes after acetazolamide injection, the percentage change in blood flow velocity was significantly lower in the hypertensive group (36.2 +/- 4.5%) than in the controls (52.6 +/- 3.7%). A significant negative correlation (p < 0.05) between decreased vasoreactivity and increased size of the left atrium and aortic root was observed. CONCLUSIONS: Vasoreactivity decreases in hypertensive patients without neurologic deficits or computed tomography abnormalities. Enlargement of the left atrium correlates well with the severity of the impairment in vasoreactivity. Transcranial Doppler sonography can be a sensitive tool in the investigation of vascular impairment caused by hypertension and in the follow-up of hypertensive patients.

Acetazolamide↗

PubMed1997

Impairment of cerebrovascular reactivity in long-term type 1 diabetes.

The early preclinical detection of cerebrovascular complications in individuals with diabetes is one of the goals of care described in the St. Vincent Declaration. In accordance with this goal, the aim of the present work was to investigate whether altered cerebral microvascular function in patients suffering from type 1 diabetes can be detected with a transcranial Doppler probe after the administration of acetazolamide. A total of 72 type 1 diabetic patients and 40 healthy control subjects entered the study. Patients were divided into two groups: those with long-term diabetes (disease duration of >10 years, n = 37) and those with short-term diabetes (disease duration of < or =10 years, n = 35). Mean blood-flow velocity in the middle cerebral artery (MCAV) was measured at rest and at 5, 10, 15, and 20 min after intravenous administration of 1 g acetazolamide with a transcranial Doppler probe and expressed as the percentage change from the pretest measurement. The percentage increase in MCAV (cerebrovascular reactivity) was calculated at each time point and compared between the groups. Cerebrovascular reserve capacity (CRC), expressed as the maximal percentage increase of the MCAV, was compared between the groups. Additionally, a reproducibility study of CRC was performed in 10 patients, using intraclass correlations. Cerebrovascular reactivity in the long-term diabetes group was lower (means +/- SD: 5 min, 23.4 +/- 15.4%; 10 min, 28.8 +/- 17.0%; 15 min, 30.0 +/- 15.6%; 20 min, 24.2 +/- 17.8%) than that of the control subjects (5 min, 43.5 +/- 23.9%; 10 min, 55.3 +/- 24.0%; 15 min, 56.7 +/- 23.8%; 20 min, 54.8 +/- 25.9%) and the short-term diabetic patients (5 min, 43.6 +/- 25.9%; 10 min, 52.2 +/- 27.7%; 15 min, 55.3 +/- 32.2%; 20 min, 45.8 +/- 35.8%). CRC was lower in the long-term diabetes group than in the control group or the short-term diabetes group. Impairment of cerebrovascular reactivity was associated with retino- and nephropathy and increased levels of fibrinogen. In contrast, CRC was independent from actual glucose, insulin, glycosylated hemoglobin, von Willebrand factor antigen, and alpha-2 macroglobulin levels. Transcranial Doppler measurements of the changes in MCAV after stimulation with acetazolamide can detect altered cerebral microvascular function in patients with diabetes. Cerebrovascular reactivity and reserve capacity are reduced in patients with long-term diabetes. Further prospective studies should delineate the clinical significance of our results.

Acetazolamide↗

PubMed1997

[Angiographical evaluation of extracranial carotid artery: comparison between Japanese and Hungarian].

We investigated the cervical level of carotid bifurcation, diameter of common carotid artery (CCA) and internal carotid artery (ICA) in 147 Japanese patients (150 arteries, range of age 31-79) and in 490 Hungarian patients (517 arteries, range of age 12-77). The cervical level of carotid bifurcation was determined by comparison with cervical vertebra. The carotid bifurcation of Japanese was most frequent at the lower part of 3rd cervical vertebra but in Hungarian the bifurcation was most frequent at the middle part of 4th cervical vertebra. Japanese carotid bifurcation was high-positioned compared with Hungarian. The mean CCA diameter in Japanese was 7.47 mm in male and 7.07 mm in female, in Hungarian 9.24 mm in male and 7.80 mm in female. The mean ICA diameter in Japanese was 4.96 mm in male and 4.83 mm in female, in Hungarian 8.56 mm in male and 7.66 mm in female. CCA and ICA diameter were larger in male than in female. The diameter of CCA had a significantly positive correlation with age (p < 0.002) but ICA had no similar correlation.

Adolescent↗

PubMed1996

[Cerebrovascular reactivity in insulin dependent diabetes mellitus studied by an acetazolamide test].

The aim of this study was to investigate, whether the cerebrovascular reactivity (CR) was altered in diabetes mellitus and to evaluate the influence of diabetes's duration on cerebrovascular reactivity. Transcranial Doppler-Acetazolamide tests were performed on 20 insulin-dependent diabetics and in 19 controls. Patients were divided into two groups, each group consisted of 10 patients: diabetics with > 10 years disease duration and with < 10 years diseases duration. Middle cerebral artery mean velocities were measured at rest and after i.v. administration of Ig Acetazolamide (AZ). There were no differences in the absolute velocities between controls and diabetics. The percentual increase of the mean velocity after AZ was slower and less intensive in longterm diabetics (means +/- SE: 5 min: 19.4 +/- 2.8%, 10 min: 28 +/- 3.6%, 15 min: 25.7 +/- 3.8%, 20 min: 23.9 +/- 4.3%), than that in controls (5 min: 32.3 +/- 4.3% -p < 0.05-, 10 min: 45.1 +/- 4.9% -p < 0.05-, 15 min: 47.5 +/- 4.3% -p < 0.01-, 20 min: 46.5 +/- 4.7% -p < 0.01) as well as in diabetics with < 10 years disease duration (5 min.: 39.5 +/- 7% -p < 0.05-, 10 min.: 49.2 +/- 6.5% -p < 0.05-, 15 min.: 53.9 +/- 8.6% -p < 0.01-, 20 min: 32.9 +/- 5.9% -n.s.). The cerebrovascular reactivity is impaired in diabetics after long duration of the disease. The altered cerebrovascular reactivity might be caused by angiopathy of the cerebral arterioles.

Acetazolamide↗

PubMed1996

[Positron emission tomography: foundations and applications].

Positron emission tomography (PET) is a non-invasive biomedical imaging technique whereby the distribution of biological tracer molecules, labelled by positron emitting isotopes, in the living body can be studied quantitatively. As theoretically an metabolically active molecule can be labelled, the technique is applicable to the measurement of any biochemical or physiological process in proper anatomical context. The introduction of PET has revolutionised the exploration of normal physiological functions. With the help of technique, among others, anatomical structures underlying mental functions can be localised in the human brain, the receptor architecture of the nervous system can be mapped, or the kinetics of pharmacons can be properly measured and modelled. In the clinical practice, PET has proven to be a uniquely useful diagnostic technique in neurology, psychiatry, cardiology, and oncology in establishing primary diagnosis and differential diagnosis, designing therapeutic interventions as well as assessing their efficacy. Hungary's and Central European region's first PET center has been established at the University Medical School in Debrecen.

Humans↗