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A summary of the fundamental lines of medical equipment for Cuban public health developed by the Center for Technological Applications and Nuclear Development (CEADEN) is made. These lines are grouped in two fundamental directions: optical instrumentation and nuclear instrumentation for medical diagnosis, quality control and dosimetry. The main developments and impacts achieved in these two directions in the National Health System are exposed, as well as their perspectives for present and future developments. [ABSTRACT FROM AUTHOR]

Prostate cancer, with a high incidence and as the second cause of death among the male population, constitutes a serious health problem that worsens over the years. The early diagnosis and the correct staging of this disease are important for the adequate management of the patient. In this sense, Nuclear Medicine molecular imaging is very useful, so the development of new peptidomimetic molecules with affinity for membrane receptors overexpressed in prostate cancer, such as prostate specific antigen (PSMA), has allowed making a qualitative step forward for the early detection and monitoring of prostate carcinoma. The present work is aimed at providing an overview of the status of PSMA inhibitor peptides, derived from the sequence -Lys-Urea-Glu-, as radiopharmaceuticals for the study of prostate neoplasms, which are currently in different stages of development, showing, in general, a high specificity, an adequate uptake into the tumor tissue and a satisfactory pharmacokinetics, to be used in the study of prostate cancer, both by positron emission tomography (PET), and by single photon emission computed tomography (SPECT). [ABSTRACT FROM AUTHOR]

Hyperthyroidism is one of the most frequent MN treatments; however, quantification of 131I activity in thyroid using Single Photon Computer Tomography (SPECT) and combined with Computer Tomography (SPECT/CT techniques has almost no bibliographic history. This work studied the impact on 131I activity accuracy quantification of scatter corrections using CT information. Three sources of known activity were used for the calibration process (1.06 MBq 2.61 MBq and 4.66 MBq) with a typical uncertainty of 2.4 % and the classic thyroid phantom. The calibration factors and their uncertainty were calculated for each case. To analyze the accuracy of the system, a set of 11 sources (with activities between 1.37 MBq-3.92 MBq) were calculated and the uncertainty was estimated in each case. The relative discrepancies of the calculated activity versus reference were compared (p<0.05). The lowest average discrepancy resulted was 3 % (from 5 to 7 %) corresponding with any correction using CT. The uncertainties were found in the range of 9 to 11 %, being consistent with the discrepancies already found. Conclusions: The corrections of attenuation and dispersion by MC using CT information did not improve the 131I activity quantification accuracy in the geometry of classical thyroid phantom; although it is recommended to expand the range of masses of the thyroid to better represent the wide specific patient clinical situation and confirm these results. [ABSTRACT FROM AUTHOR]

Nuclear medicine (NM) diagnostic procedures use ionizing radiation and it is necessary to ensure that the amount of prescribed activity is as low as reasonably achievable. Optimizing these procedures, one of the greatest challenges facing Nuclear Medicine today, is based on achieving a balance between image quality and radiation dose. The objective of this article is to establish and validate a method for optimization studies of medical exposure in NM simulating different levels of activity that can be applied in patients without violating the ethical and radiological protection principles. The method is based on the recombination of data obtained in gated acquisitions to simulate activity levels. For this, measurements were made using different phantoms and a signal generator. A python code was developed that allows the different activity levels to be simulated automatically from a single gated acquisition and returns the studies in the same dicom format to be reconstructed in the registered processing program provided by the manufacturer. To validate our method, the linear dependence of the number of total counts with the simulated activity levels was demonstrated and the quality of the reconstructed images vs the simulated activity levels was qualitatively evaluated. This method constitutes a valid and applicable proposal in the majority of nuclear medicine services in the country to implement optimization procedures for SPECT studies, contributing to a reduction in population exposure to radiation, due to high-tech diagnostic tests. [ABSTRACT FROM AUTHOR]

The diagnostic image must be carried out with the minimum necessary exposure of the patient that allows the objective of the diagnosis to be satisfactorily achieved. For this reason, diagnostic reference levels emerge and are established as dynamic tools to help optimize radiation protection, contribute to the standardization of practices and strengthen culture of safety, without compromising the clinical purpose of each examination or process. The objective of this work is to provide an updated overview of the establishment and use of these levels for nuclear medicine and hybrid imaging. It is identified that to establish and use them properly, trained personnel and coordination and collaboration activities are required among multiple actors, including medical services, health authorities, professional organizations and regulatory bodies. The accelerated development of technology generally exceeds the change in regulations, so these levels must be updated periodically, in order to fulfil their role as a guide and spur for optimization. The worldwide expansion of hybrid technologies and their growing use are a phenomenon of the last decade, so the establishment of these levels for such technologies has not been consolidated, although countries such as the United Kingdom and Australia show solid steps in this address. Research has been carried out with phantoms and directly with patients, the latter with a more useful contribution of information. The installation of hybrid equipment in Cuba demands this study, hence its importance. [ABSTRACT FROM AUTHOR]

El síndrome cognitivo afectivo cerebeloso (SCAC) se caracteriza por alteraciones a nivel cognitivo (síndrome disejecutivo, déficit visuoespacial, lenguaje...), asociado a cambios afectivos/emocionales. Su fisiopatología no es bien conocida y en la actualidad no existe tratamiento específico. Describimos a un hombre de 64 años con cuadro poco frecuente de trastorno cognitivo-conductual tras un infarto en la arteria cerebral media izquierda, dominado por disfunciones ejecutivas, apraxia de predominio oral, atención dividida interrumpida, organización visuoespacial perturbada y anomalías afectivas con una gran apatía, y cuyos síntomas mejoraron con un inhibidor selectivo de la recaptación de la serotonina (ISRS). En ausencia de daño estructural cerebeloso. una tomografía computarizada de perfusión cerebral por emisión de fotón único usando 99mTc-hexametil-propileno-aminoxima (SPECT-HMPAO) mostró una hipoperfusión izquierda frontotemporal y parietoccipital de etiología vascular ya conocida, y una hipoperfusión en hemisferio cerebeloso derecho compatible con fenómeno de diasquisis cruzada. Presumimos que los déficits cognitivos y afectivos están agravados por la interrupción funcional de las interconexiones cerebelosas recíprocas con áreas de asociación cerebral y corteza paralímbica, alterando la contribución del cerebelo al procesamiento y modulación cognitiva y afectiva. En el caso descrito, tanto la situación clínica como las imágenes funcionales de control mejoraron tras tratamiento con ISRS, lo que plantea la posibilidad de que exista conectividad de algunas proyecciones con transmisión serotoninérgica entre el cerebelo y las cortezas de asociación contralateral, y que dicha conectividad disfuncional esté involucrada en la fisiopatología del SCAC. [ABSTRACT FROM AUTHOR]

The introduction in Cuba of imaging hybrid systems in nuclear medicine has become a challenge for medical physicist in order to guaranty the patient´s radiation safety and proper dose estimation. The aim of this study was to retrospectively evaluate the CT radiation doses for studies performed with a SPECT/CT hybrid system (SPECT/CT). A MATLAB “in house” made tool was tested and validated for this purpose. 62 patients with CT studies were manually and automatically reviewed; the tool could visualize and properly recover the patient personal information, CT protocol and dose related data from the DICOM header in the SPECT/CT study file. The CT volume dose index (CTDIvol) parameter was used for calculating the CT dose-length product (DPL) and the effective doses (E). The CT radiation dose preliminary results were on the range of those reported by others authors for the typical studies, demonstrating the efficacy of the tool developed and the CT dose assessment method. [ABSTRACT FROM AUTHOR]

The paper is aimed at establishing the association of the dyslipidemia with the positive results of the myocardial perfusion SPECT, for the optimization of use. 152 MPSPECT were analyzed, different days, for an average age of 58.32 years, 86 (56.6%), were males. Considering the presence of dyslipidemia, the patients were divided into two groups: dyslipidemia, n = 37(24.3%) and not-dyslipidemia, n = 115 (75.7%). No significant differences were present in the age average (59.59/57.90, p = 0.284), in the body mass index (24.85/25.03, p=0.739), nor in the frequency of mature. Therefore, only dyslipidemia contributes to therefore the additional risk. Result: 102 (67.1%) MPSPECT were positive. In the comparison among groups no significant difference in the incidence of positive results was observed (67.60/67.00, p = 0.945), and the same situation remained when the groups were subdivided into symptomatic and asymptomatic. As a result of the study, it was concluded that dyslipidemia does not represent a significant risk of ischemic cardiopathy in patients within the ages of risk, therefore there is no significant association with the positive results of the SPECTPM, within patients in ages of risk. [ABSTRACT FROM AUTHOR]

The molecular imaging of in vivo cellular processes using preclinical animal studies and SPECT technique is one of the main reasons for the design of new devices with high spatial resolution. As an auxiliary tool, Monte Carlo simulation has allowed the effective characterization and optimization of those medical imaging systems. At present there is a new simulation framework called GAMOS (GEANT4-based Architecture for Medicine-Oriented Simulations); which code, libraries and particle transport method correspond to those developed by GEANT4 and contains specific applications for nuclear medicine. This tool has been already validated for PET technique by comparison with experimental data, while not yet been done the correct evaluation of GAMOS for SPECT systems. Present work have demonstrated the potential of GAMOS in obtaining simulated realistic data using this nuclear imaging technique. For this purpose, simulation of a novel installation "rSPECT", devote to study rodents, has been done. The study comprises the collimation and detection geometries and the fundamental characteristics of the previuos published experimental measurements for rSPECT installation. Studies have been done using 99mTc and 20% energy window. Sensitivity values obtained by simulation revealed an acceptable agreement with experimental values. Therefore we can conclude that simulation results have shown good agreement with the real data. This fact allowed us to estimate the behavior of the new GEANT4 simulation platform "GAMOS" in SPECT applications and have demonstrated the feasibility of reproducing experimental data. [ABSTRACT FROM AUTHOR]

Parkinson disease (PD) is a motor syndrome that is associated with dopamine deficiency to degenerate the subcortical nucleus that produces it. While demonstrations are almost exclusively motor, research in recent decades have shown that cognitive disorders are part of the clinical symptoms of PD, there are many gaps that occur in this disease, which include impaired attention, orientation, the executive system deficits, impaired visuospatial processing and language by which neuropsychological evaluation was performed using the Barcelona test in PD patients and the results were correlated with the levels obtained by SPECT perfusion brain. [ABSTRACT FROM AUTHOR]

Introduction. Autistic disorder is formed by a group of abnormalities, which include qualitative impairments in communication, reciprocal social interactions, as well as the adoption of stereotyped repetitive behavior patterns and restrictive. Objective. Identify the differences in regional cerebral perfusion measured by SPECT technique in children with autistic disorder compared to control children. Material and methods. We performed a prospective, transversal, comparative, observational pediatric patients with autism and a control group, conducted a brain scan technique to quantify cerebral perfusion SPECT in the frontal lobes, parietal, occipital, temporal and Brodman areas in its left and right hemispheric parts: 1, 2, 3, 4, 6, 8, 9, 10, 17, 18, 19, 22, 41, 44, 45. Drug was used radio tc- 99m ethyl cysteine dimer bike, images were processed using the protocol Talairach brain imaging that allowed quantification of brain activity in account activity for each area of interest, we analyzed the characteristics and differences in cerebral perfusion for each of the segments studied in both study groups. Results. Autistic patients show an increase in cerebral perfusion of the right frontal lobe (54.4 vs. 48.7%) (p < 0.04385). Also have loss of cortical perfusion asymmetry of the frontal lobes (54.4 vs. 54.7%) (p = 0.6816). Conclusions. Patients showed asymmetry constant control of cerebral perfusion between right and left frontal lobe (55.1 vs. 48.6%) (p < 0.004586). Autistic patients show increased cerebral perfusion in Brodmann area 45 of right. (60.4 vs. 54.3%) (p = 0.0500). [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most common cause of dementia and there is no cure for this disease. It is known that it is triggered by the apparition of the senile plaques produced for the agglomeration of β-amyloid peptides. AD´s reliable diagnosis is done post-mortem. Recently, non-invasive methods are evaluated for in vivo diagnosis of this disease by means of imaging techniques PET (Positron Emission Tomography), SPECT (Single Photon Emission Computed Tomography) and MRI (Magnetic Resonance Imaging). In the case of the SPECT technique, new organic compounds labeled with radionuclides 123I, 125I, and 99 mTc have been described. Epidemiological studies have revealed that the use of non-steroidal anti-inflammatory drugs decreases the relative risk of AD. In the last years, the search of compounds with similar structures it has increased in order to be used as labels or drugs. The objective of this paper was to synthesize new naphthalene derivatives, for its further use as quelating agents of 99 mTc, for the detection of β-amyloid plaque in the AD. Thus, spacer arms with different lengths were introduced at β-position (or 1-) of naphthalene molecule through various different reactions. The compounds were structurally characterized by IR, 1H-NMR and 13C- NMR spectroscopies and mass spectrometry. [ABSTRACT FROM AUTHOR]

Coronary artery disease (CAD) remains the leading cause of death in the Western world, and early detection of CAD allows optimal therapeutic management. The gold standard has always been invasive coronary angiography, but over the years various non-invasive techniques have been developed to detect CAD, including cardiac SPECT and cardiac computed tomography (Cardiac CT). Cardiac SPECT permitted visualization of myocardial perfusion and have focused on the assessment of the hemodynamic consequences of obstructive coronary lesions as a marker of CAD. Cardiac CT focuses on the detection of atherosclerosis rather than ischemia, and permit detection of CAD at an earlier stage. Objectives of this manuscript are to discuss the clinical experience with both modalities and to provide a critical review of the strengths and limitations of Cardiac SPECT and Cardiac CT for the diagnostic and management of patients with suspected CAD or cardiac ischemic disease. [ABSTRACT FROM AUTHOR]

Both cognitive regression and behaviour disorders had been associated gabaergic antiepiletic medication in patients with rolandic epilepsy, nevertheless the cause-effect relation of this phenomenon had not been evaluating. Objective: To describe the clinical and functional evolution of patients with Benign Childhood Epilepsy of Infancy with centro-temp spikes without antiepileptic medication until presentation of complications. Patients and method: A roup of 45 patients with rolandic epilepsy were assessed with clinical and serial sleep and wake electroencephalograms, Single Photon Emission Tomography and Neuropsychological tests. The patients were followed from the diagnosis up to they presented complications such as: cognitive deficits, electrical status during slow sleep and cluster seizures. Neuropsychological skills were compared with those of a group of children of similar age and sex (control group). P<0.05 value was considered as significant. Results: The study included 45 children, 17 had cluster seizures, 11 showed electrical status during slow wave sleep and 14 had cognitive deficits. All complication were found inpatient without antiepileptic medication. Conclusions: Complicated variants of rolandic epilepsy depend on genetic subtypes with variable phenotypic expression. Gabaergic antiepileptic drugs could be a trigger factor acting in special genetically predisposed patients but they are not the cause. [ABSTRACT FROM AUTHOR]