introduction:brain imaging with f-18 fluorodeoxyglucose (18f-fdg) positron ‎emission tomography or tc-99m hexamethylpropyleneamine oxime (‎99mtc-hmpao) spect is widely used for the evaluation of alzheimer's ‎dementia (ad); we aim to assess superiority of one method over the ‎other. methods: twenty four patients with clinical diagnosis of alzheimer disease ‎underwent 18f-fdg pet and ‎99mtc-...

UNLABELLED The aim was to compare ventilation/perfusion SPECT lung scintigraphy (V/Q-SPECT) and computed tomography pulmonary angiography (CTPA) in patients with suspicion of pulmonary embolism (PE). MATERIAL AND METHODS This prospectively designed study included 53 patients with intermediate or high clinical probability of PE. A V/Q-SPECT and CTPA was performed on all patients. The V/Q-SPECT...

introduction:patients with the coronary slow flow phenomenon (scf) frequently experience angina episodes. the purpose of this study was to determine efficacy of nicorandil in myocardial perfusion in patients with scf. methods: twenty patients (50.85 ± 12.96 y) with scf were studied.  we evaluate coronary slow flow according to protracted thrombolysis in myocardial infarction (timi) frame count....

introduction: spect is a diagnostic imaging technique the main disadvantage of which is the existence of poisson noise. so far, different methods have been used by scientists to improve spect images. the wavelet transform is a new method for de-noising which is widely used for noise reduction and quality enhancement of images. the purpose of this paper is evaluation of noise reduction in spect ...

Collective bremsstrahlung of vector meson fields in relativistic nuclear collisions is studied within the time–dependent Walecka model. Mutual deceleration of the colliding nuclei is described by introducing the effective stopping time and average rapidity loss of baryons. It is shown that electromagnetic decays of virtual ω–mesons produced by bremsstrahlung mechanism can provide a substantial ...

A self-organizing network according to a modiied Kohonen algorithm was used for the identiication of 272 Events of pp-bremsstrahlung in a pp-scattering experiment at the SATURNE accelerator at T beam =1.0 GeV. 1. Identiication of the pp-bremsstrahlung One of the experimental goals being pursued by means of the TOF-spectrometer 1] at the COSY accelerator at the Forschungszentrum J ulich is the m...

Single-photon emission computed tomography (SPECT) and conventional scintigraphy were compared in 130 patients examined to assess hepatic involvement in malignant disease. Transmission computed tomography (TCT) served as the reference method against which SPECT and conventional scintigraphy were compared. The sensitivity of SPECT was calculated for lesions grouped according to diameter as well ...

Moyamoya disease (MMD) is a cerebrovascular disorder involving stenosis of brain vessels. Brain perfusion SPECT in MMD demonstrates impaired perfusion in ischemic areas. We present a 6-year-old boy with MMD. The patient had numbness on the right arm and simultaneous electroencephalography changes while studying arms up on the table. To differentiate seizure and ischemic symptoms, brain perfusio...

Single Photon Emission Computed Tomographic im-ages(SPECT) have relatively poor resolution. In an attempt to improve SPECT image quality, many methods have been developed for including anatomic information, extracted from higher resolution, structurally correlated Magnetic Resonance images(MRI), into SPECT reconstruction process. These methods provide improved SPECT reconstruction accuracy if t...

A new approach to the calculation of the x-ray spectrum emerging from an x-ray tube is proposed. Theoretical results for the bremsstrahlung cross section appearing in the literature are summarized. Four different treatments of electron penetration, based on the work presented in Part I, are then used to generate bremsstrahlung spectra. These spectra are compared to experimental data at 50, 80 a...