RESUMEN
Abstract There is no biodistribution or imaging data on 99mtechnetium (Tc)-hexamethyl propylamine oxime (HMPAO)-labeled platelets in the literature. The current study aimed to present updated information about the clinical procedures for preparation and use of labeled platelets. Following two-step centrifugation at 1500 and 2500 rpm, the platelets were extracted from whole blood into platelet-rich plasma (PRP) above the buffy coat and then from PRP into a platelet pellet at the bottom of the tube. The 99mTc-HMPAO-labeled platelets were inspected for purity, viability, release of 99mTc from platelets, and sterility. Also, microscopic examination and thin layer chromatography (TLC) were performed. Biodistribution was assessed following necropsy in BALB/c mice and through imaging of New Zealand rabbits. The separation ratio was estimated at 98%, and radiochemical purity was measured to be 80%. The labeling efficiency was above 30% in more than half of the assays (range: 17-43%). The release of 99mTc from platelets was 9% per hour at 37ºC. After 24 hours, stability was estimated at 54% in the human serum. The target organs of mice included the spleen and liver. In rabbits, the imaging results indicated liver as the target organ. Thyroid uptake was negligible up to 90 minutes. Based on the findings, extraction of platelets and labeling them with 99mTc-HMPAO is a feasible and safe approach in routine practice.
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Humanos , Animales , Masculino , Ratones , Control de Calidad , Plaquetas/clasificación , Exametazima de Tecnecio Tc 99m , Métodos , Bazo , Cromatografía en Capa Delgada/métodos , Eficiencia/clasificación , Plasma Rico en Plaquetas , HígadoAsunto(s)
Aneurisma de la Aorta/complicaciones , Aneurisma de la Aorta/etiología , Infecciones por Salmonella/complicaciones , Salmonella enteritidis , Trombosis/etiología , Aneurisma de la Aorta/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Infecciones por Salmonella/diagnóstico por imagen , Exametazima de Tecnecio Tc 99m , Trombosis/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
Functional brain imaging with brain single photon emission computer tomography (Brain SPECT) has been used for many years in the evaluation of multiple neuro-degenerative and neuro-developmental disorders. Brain SPECT is a nuclear medicine tomographic study performed with a lipophilic radiopharmaceutical labeled with 99mTc-pertechnetate. It is a cerebral perfusion agent that depicts the global and regional perfusion patterns in the cortical gray matter and subcortical structures. Cornelia de Lange syndrome (CdLS) is a rare neuro-developmental and genetic condition, associated to several malformations. There are a limited number of cases reported in the medical literature and few of them report neuro-radiological and/or neuro-pathologic abnormalities. We report a case of a 15 year old patient, clinically diagnosed at birth with CdLS, who presents limited anatomical findings on Computed Tomography and Magnetic Resonance Imaging. To the best of our knowledge, this is the first report of the Brain SPECT findings in this syndrome.
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Síndrome de Cornelia de Lange/diagnóstico por imagen , Neuroimagen Funcional , Imagen por Resonancia Magnética , Tomografía Computarizada de Emisión de Fotón Único , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Encéfalo/diagnóstico por imagen , Síndrome de Cornelia de Lange/patología , Síndrome de Cornelia de Lange/psicología , Diagnóstico Diferencial , Humanos , Masculino , Fenotipo , Radiofármacos/farmacocinética , Exametazima de Tecnecio Tc 99m/farmacocinética , Distribución TisularRESUMEN
The psychiatric manifestations of three patients with systemic lupus erythematosus (SLE) and neuropathic dysautonomic processes are described. All patients had a severe form of SLE with neurological, renal, articular, pulmonary or haematological manifestations. All three have two types of psychiatric manifestations: (1) a chronic and progressive depression and (2) a complex dissociative disorder during the acute episodes of postural hypotension. A provocative test with SPECT with 99mTc-HmPAO to be done during the episode of orthostatic hypotension may contribute to clinical assessment of complex changes in cerebral regional perfusion.
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Enfermedades del Sistema Nervioso Autónomo/etiología , Enfermedades del Sistema Nervioso Autónomo/psicología , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/psicología , Adolescente , Enfermedades Autoinmunes del Sistema Nervioso/diagnóstico por imagen , Enfermedades Autoinmunes del Sistema Nervioso/etiología , Enfermedades Autoinmunes del Sistema Nervioso/psicología , Enfermedades del Sistema Nervioso Autónomo/diagnóstico por imagen , Encéfalo/irrigación sanguínea , Encéfalo/diagnóstico por imagen , Circulación Cerebrovascular , Depresión/diagnóstico por imagen , Depresión/etiología , Depresión/psicología , Trastornos Disociativos/diagnóstico por imagen , Trastornos Disociativos/etiología , Trastornos Disociativos/psicología , Femenino , Humanos , Hipotensión Ortostática/diagnóstico por imagen , Hipotensión Ortostática/etiología , Hipotensión Ortostática/psicología , Lupus Eritematoso Sistémico/diagnóstico por imagen , Radiofármacos , Exametazima de Tecnecio Tc 99m , Tomografía Computarizada de Emisión de Fotón Único , Adulto JovenRESUMEN
OBJECTIVE: Since blood viscosity (BV) is one of the most important factors determining blood flow, this study aimed to investigate the possible correlation between increased blood viscosity and reduction of regional cerebral blood flow (rCBF) in healthy ageing. METHODS: Male subjects were distributed in two groups: "young", aged 20-30 (27 volunteers), or "elderly", aged 60-70 (50 volunteers). Whole blood viscosity was obtained with a Wells-Brookfield Cone/Plate Viscometer. Cerebral blood flow was analysed by means of single photon emission computed tomography (SPECT). RESULTS: The mean BV values were 3.28±0.43 mPa in the group of young volunteers and 4.33±0.73 mPa in the group of elderly volunteers (t=-6.9, p<0.0001). The elderly had a lower blood flow than the young in the following regions: bilateral parietal; temporal-parietal and temporal of the left hemisphere. Pearson's correlation between BV and rCBF showed a good inverse correlation when the BV was above 3.95±0.83 mPa. CONCLUSIONS: Our results point to a close relationship between the two parameters analysed, BV and rCBF. The impairment in rCBF observed in the elderly volunteers might be due to an increase in BV, among other factors. SIGNIFICANCE: These findings suggest interesting possibilities for the treatment/prevention of brain ageing.
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Viscosidad Sanguínea/fisiología , Circulación Cerebrovascular/fisiología , Cerebro/irrigación sanguínea , Flujo Sanguíneo Regional/fisiología , Adulto , Anciano , Humanos , Masculino , Persona de Mediana Edad , Exametazima de Tecnecio Tc 99m , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adulto JovenRESUMEN
BACKGROUND: The injection of stem cells in the context of acute myocardial infarction (AMI) has been tested almost exclusively by anterograde intra-arterial coronary (IAC) delivery. The retrograde intravenous coronary (IVC) delivery may be an additional route. OBJECTIVE: To compare the cell distribution and retention pattern in the anterograde and retrograde routes. To investigate the role of microvascular obstruction by magnetic resonance imaging in cell retention by cardiac tissue after the injection of bone marrow mononuclear cells (BMMC) in AMI. METHODS: This was a prospective, open label, randomized study. Patients with AMI who presented: (1) successful chemical or mechanical reperfusion within 24 hours of symptom onset and (2) infarction involving more than 10% of the left ventricle (LV) at the myocardial scintigraphy were included in the study. One hundred million BMMC were injected into the infarction-related artery through IAC route, or vein through the IVC route. One percent of the injected cells were labeled with 99mTc-hexamethyl-propylene-amine-oxime (99mTc-HMPAO). Cell distribution was evaluated at 4 and 24 hours after the myocardial scintigraphy injection. Cardiac magnetic resonance imaging was performed before cell injection. RESULTS: Thirty patients were randomized into three groups. There were no serious adverse events related to the procedure. The early and late retention of labeled cells was higher in the IAC group than in IVC group, regardless of the presence of microcirculation obstruction. CONCLUSION: The injection using the retrograde approach was feasible and safe. Cell retention by cardiac tissue was higher using the anterograde approach. More studies are needed to confirm these findings.
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Trasplante de Médula Ósea/métodos , Vasos Coronarios/fisiopatología , Microcirculación/fisiología , Infarto del Miocardio/cirugía , Trasplante de Células Madre/métodos , Trasplante de Médula Ósea/efectos adversos , Vasos Coronarios/diagnóstico por imagen , Femenino , Humanos , Inyecciones Intraarteriales/métodos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/fisiopatología , Estudios Prospectivos , Cintigrafía , Radiofármacos , Estadísticas no Paramétricas , Trasplante de Células Madre/efectos adversos , Exametazima de Tecnecio Tc 99mRESUMEN
En los últimos años ha surgido un gran interés en conocer la biodistribución de las células madre en el organismo después que son infundidas o inyectadas directamente en una parte del cuerpo. Para esto se han usado diferentes procederes, entre ellos, el marcaje de las células con diferentes fluorocromos, tales como la proteína con fluorescencia verde y la proteína con fluorescencia roja; o bien se les hace una transfección con plasmidos que codifican proteínas fluorescentes o se emplean sondas moleculares fluorescentes para la identificación de cromosomas. Recientemente se han introducido técnicas imagenológicas de avanzada no invasivas, entre las que tenemos la resonancia magnético nuclear, así como procederes basados en el marcaje con radionúclidos para la obtención de imágenes detectadas por tomografía por emisión de positrones (PET, del inglés positron emission tomography), o por tomografía computarizada por emisión de fotón único (SPECT, del inglés single- photon emission computed tomography)(AU)
In past years there was an increasing interest by to know about the biodistribution of stem cells in organism after its perfusion or direct injection in a part of the body. Thus, we used different procedures including the cell labeling with distinct fluorochromes, such as the green fluorescence protein and the red fluorescence protein or a plasmid transfection codifying the fluorescent proteins of fluorescent molecular stents to identify the chromosomes. Recently non-invasive leading imaging techniques have been introduced including nuclear magnetic resonance. As well as procedures based on radionuclide labeling to obtain the positron emission tomography (PET) images or by photon-emission computed tomography (SPECT)(AU)
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Humanos , Masculino , Femenino , Rastreo Celular/métodos , Células Madre , Investigación con Células Madre/historia , Exametazima de Tecnecio Tc 99m , Tomografía Computarizada de Emisión de Fotón Único/métodosRESUMEN
UNLABELLED: Brain SPECT imaging (BSI) with statistical parametric mapping (SPM) offers a clear and accurate vision of perfusion changes. OBJECTIVE: To study brain perfusion abnormalities in adolescents' dependent of multiple drugs. METHOD: Sixteen male patients (15.1 + or - 2.1 years) were submitted to (99m)Tc-HMPAO BSI with SPM. RESULTS: Cortical hypoperfusion occurred in 7/16 patients (44%). There was a significant inverse correlation between the number of hypoperfused regions and the patient's age (p= -0.6737; p=0.004) and with the age when the drug dependence began (p= -0.5616; p=0.023). There was also a tendency towards an inverse correlation between regions of hypoperfusion and the duration of the drug dependence. CONCLUSION: BSI with SPM can help detect hypoperfusion in adolescents dependent on multiple drugs. The younger the patients, the more regions of hypoperfusion are noted. Probably, the neuronal plasticity has an important role in this phenomenon because the highest neural activity occurs in childhood.
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Mapeo Encefálico , Encéfalo/irrigación sanguínea , Encéfalo/diagnóstico por imagen , Trastornos Relacionados con Sustancias/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único , Adolescente , Factores de Edad , Niño , Humanos , Masculino , Radiofármacos , Exametazima de Tecnecio Tc 99m , Factores de TiempoRESUMEN
AIM: To evaluate inflammatory activity in patients with Crohn's disease (CD) using technetium-99m-hexamethylpropyleneamine oxime (99mTc-HMPAO) granulocyte scintigraphy. METHODS: Twenty patients (7 male and 13 female) with CD and five healthy volunteers were selected for 99mTc-HMPAO granulocyte scintigraphy. The Crohn's Disease Activity Index (CDAI), blood tests and C-reactive protein (CRP) of each patient were performed 7 d before the scintigraphic images. The leukocytes were labeled according to the International Society of Radiolabeled Blood Elements (ISORBE) consensus protocol and the scintigraphic images, including single photon emission computed tomography, were obtained 30 min and 2 h after injection of the radiolabeled leukocytes. RESULTS: The labeling yield of the leukocytes with the lipophilic complex 99mTc-HMPAO was 55.0% +/- 10%. Six of the 20 patients (30%) presented congruent results for the three parameters investigated (CDAI, Scintigraphic Index and CRP). On the other hand, 14 patients (70%) did not show congruent results. There was no significant correlation between the indices analyzed according to the Spearman test (P > 0.05, n = 20). CONCLUSION: The results suggest that 99mTc-HMPAO-labeled leukocyte scintigraphy could be important for determining inflammatory activity in CD even in the absence of clinical symptoms.
Asunto(s)
Enfermedad de Crohn/metabolismo , Leucocitos/metabolismo , Radiofármacos/farmacocinética , Índice de Severidad de la Enfermedad , Exametazima de Tecnecio Tc 99m/farmacocinética , Adulto , Proteína C-Reactiva/metabolismo , Estudios de Casos y Controles , Enfermedad de Crohn/diagnóstico , Femenino , Humanos , Inflamación/diagnóstico , Inflamación/metabolismo , Masculino , Persona de Mediana Edad , Cintigrafía , Sensibilidad y EspecificidadRESUMEN
PURPOSE: To evaluate the ability of polymeric nanocapsules (NCs) radiolabeled with technetium-99m D,L-hexamethylpropyleneamine oxime (Tc-HMPAO) to identify inflammatory process in an experimental model. METHODS: NCs were prepared by interfacial deposition of preformed biodegradable polymer [poly (D,L-lactic acid) (PLA) and PLA-PEG (polyethyleneglycol)] followed by a solvent displacement. The size and homogeneity, and zeta potential of the NC preparations were determined in a Zetasizer by photon correlation spectroscopy and laser Doppler anemometry, respectively. The NCs radiolabeled with Tc-HMPAO were administered intravenously to Wistar male rats bearing a focal inflammation induced by subplantar injection of carrageenan in the right foot. At preestablished time intervals, the animals were anesthetized, tissues were removed and radioactivity was determined using an automatic scintillation apparatus. RESULTS: The average diameter calculated by photon correlation spectroscopy varied from 216 to 323 nm. The biodistribution studies showed a greater uptake of the PEG surface-modified Tc-HMPAO-NC by the inflamed paws when compared with the respective controls. There was no significant difference in the uptake of conventional Tc-HMPAO-NC and of free Tc-HMPAO by inflamed and control paws. These results indicate that the PLA-PEG Tc-NC showed a higher uptake in inflammation compared with free complex and may be useful as a radiotracer to identify these foci.
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Inflamación/diagnóstico , Inflamación/metabolismo , Nanocápsulas/química , Exametazima de Tecnecio Tc 99m/farmacocinética , Animales , Marcaje Isotópico , Masculino , Ratas , Ratas Wistar , Exametazima de Tecnecio Tc 99m/química , Distribución TisularRESUMEN
The objective of this study was to investigate safety and feasibility of autologous bone marrow mononuclear cells (BMMNC) transplantation in ST elevation myocardial infarction (STEMI), comparing anterograde intracoronary artery (ICA) delivery with retrograde intracoronary vein (ICV) approach. An open labeled, randomized controlled trial of 30 patients admitted with STEMI was used. Patients were enrolled if they 1) were successfully reperfused within 24 h from symptoms onset and 2) had infarct size larger than 10% of the left ventricle (LV). One hundred million BMMNC were injected in the infarct-related artery (intra-arterial group) or vein (intravenous group), 1% of which was labeled with Tc(99m)-hexamethylpropylenamineoxime. Cell distribution was evaluated 4 and 24 h after injection. Baseline MRI was performed in order to evaluate microbstruction pattern. Baseline radionuclide ventriculography was performed before cell transfer and after 3 and 6 months. All the treated patients were submitted to repeat coronary angiography after 3 months. Thirty patients (57 +/- 11 years, 70% males) were randomly assigned to ICA (n = 14), ICV (n = 10), or control (n = 6) groups. No serious adverse events related to the procedure were observed. Early and late retention of radiolabeled cells was higher in the ICA than in the ICV group, independently of microcirculation obstruction. An increase of EF was observed in the ICA group (p = 0.02) compared to baseline. Injection procedures through anterograde and retrograde approaches seem to be feasible and safe. BMMNC retention by damaged heart tissue was apparently higher when the anterograde approach was used. Further studies are required to confirm these initial data.
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Trasplante de Médula Ósea/métodos , Leucocitos Mononucleares/trasplante , Infarto del Miocardio/terapia , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Demografía , Femenino , Humanos , Inyecciones , Masculino , Persona de Mediana Edad , Nitratos , Ventriculografía con Radionúclidos , Exametazima de Tecnecio Tc 99m , Tecnecio Tc 99m Sestamibi , Trasplante AutólogoRESUMEN
The present work describes the preparation, characterization and labelling of conventional and surface-modified nanocapsules (NC) with 99m Tc-HMPAO. The size, size distribution and homogeneity were determined by photon correlation spectroscopy (PCS) and zeta potential by laser doppler anemometry. The morphology and the structural organization were evaluated by atomic force microscopy (AFM). The stability and release profile of the NC were determined in vitro in plasma. The results showed that the use of methylene blue induces significant increase in the encapsulation efficiency of 99m Tc-HMPAO, from 24.4 to 49.8% in PLA NC and 22.37 to 52.93% in the case of PLA-PEG NC (P<0.05) by improving the complex stabilization. The average diameter of NC calculated by PCS varied from 216 to 323 nm, while the average diameter determined by AFM varied from 238 to 426 nm. The AFM analysis of diameter/height ratios suggested a greater homogeneity of the surface-modified PLA-PEG nanocapsules compared to PLA NC concerning their flattening properties. The in vitro release of the 99m Tc-HMPAO in plasma medium was faster for the conventional PLA NC than for the surface-modified NC. For the latter, 60% of the radioactivity remained associated with NC, even after 12h of incubation. The results suggest that the surface-modified 99m Tc-HMPAO-PLA-PEG NC was more stable against label leakage in the presence of proteins and could present better performance as radiotracer in vivo.
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Lactatos/química , Microscopía de Fuerza Atómica/métodos , Nanocápsulas/química , Polietilenglicoles/química , Análisis Espectral/métodos , Exametazima de Tecnecio Tc 99m/farmacocinética , Algoritmos , Estabilidad de Medicamentos , Excipientes/química , Flujometría por Láser-Doppler/métodos , Azul de Metileno/química , Estructura Molecular , Tamaño de la Partícula , Fotones , Solubilidad , Electricidad Estática , Exametazima de Tecnecio Tc 99m/química , Factores de TiempoRESUMEN
PURPOSE: To investigate the biodistribution and the ability of stealth pH-sensitive liposomes radiolabelled with 99mTc to identify inflammatory regions in a rat focal inflammation model. METHODS: Preformed glutathione-containing stealth pH-sensitive liposomes were labelled with 99mTc-hexamethylpropylene amine oxime (99mTc-HMPAO). The 99mTc-HMPAO radiolabelled stealth pH-sensitive liposomes (99mTc-SpHL) were administered intravenously in Wistar male rats with inflammation induced by injection subplantar of carrageenan in the right foot. At pre-established time intervals the animals were anaesthetized and tissues were removed and analysed for 99mTc content using an automatic scintillation apparatus. Scintigraphic imaging was also performed after 2, 4 and 8 h of intravenous injection of 99mTc-SpHL. RESULTS: The 99mTc-SpHL was significantly taken up by the spleen (19.21+/-2.98%ID/g at 30 min post-injection). Low radioactivity levels were found in the liver, lungs, and kidney. Moreover, the 99mTc-SpHL uptake was significantly higher in the inflamed foot when compared to the respective control (0.386+/-0.059 and 0.215+/-0.018%ID/g at 2 h post-injection, respectively). As early as 30 min after administration of 99mTc-SpHL, the focus of inflammation could be visualized scintigraphically. The value of the inflammatory and non-inflammatory site radioactivity counting ratio was greater than 5. CONCLUSION: This result indicates that the 99mTc-SpHL presents a high tropism for inflammatory regions and may be useful as a radiopharmaceutical to identify these foci.
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Portadores de Fármacos/química , Inflamación/diagnóstico por imagen , Inflamación/metabolismo , Liposomas/química , Exametazima de Tecnecio Tc 99m/farmacocinética , Animales , Concentración de Iones de Hidrógeno , Masculino , Tasa de Depuración Metabólica , Especificidad de Órganos , Cintigrafía , Radiofármacos/química , Radiofármacos/farmacocinética , Ratas , Ratas Wistar , Exametazima de Tecnecio Tc 99m/química , Distribución TisularRESUMEN
Cranial osteomyelitis is a potentially fatal lesion. White blood cell scanning (WBC) with 99mTc-hexamethylpropylene amine oxime (HMPAO) has proven highly sensitive and specific in the diagnosis and follow-up of patients with suspected osteomyelitis. In this report we show the usefulness of SPECT and transmission CT performed simultaneously using a hybrid imaging device for the functional anatomic mapping of soft tissue and cranial bone infections. 99mTc-HMPAO-labeled leukocytes scintigraphy was performed on an elderly diabetic man with an intracranial mass lesion and with suspected temporal bone infection. Planar scans were acquired 30 min, 4 h, and 24 h after injection. SPECT/CT was obtained 6 h after tracer injection, using a dual-head camera coupled with a low-power X-ray tube. The scintigraphic results were matched with the results of surgery and of clinical follow-up. The planar images alone were true-positives for abscess in this patient. SPECT/CT improves the accuracy of99mTc-HMPAO scintigraphy especially in discriminating between soft-tissue and bone involvement. In fact, SPECT/CT also showed temporal bone osteomyelitis. This result indicates that SPECT/CT performed using a hybrid device can improve imaging with 99mTc-HMPAO-labeled leukocytes in patients with suspected osteomyelitis by providing accurate anatomic localization and precise definition of the extent of infection.
Asunto(s)
Absceso Encefálico/diagnóstico por imagen , Leucocitos/diagnóstico por imagen , Osteomielitis/diagnóstico por imagen , Radiofármacos , Exametazima de Tecnecio Tc 99m , Anciano , Humanos , Masculino , Reproducibilidad de los Resultados , Hueso Temporal , Tomografía Computarizada de Emisión de Fotón Único/métodosRESUMEN
PURPOSE: To evaluate the feasibility of using the Statistical Parametric Mapping (SPM) program for an automated, voxel-by-voxel assessment of regional cerebral blood flow (rCBF) deficits in Alzheimer's disease (AD) subjects relative to age-matched controls studied with a conventional, single-detector SPECT system. METHODS: We used a databank of 99mTc-HMPAO images of 19 patients with a diagnosis of probable AD and 15 elderly healthy volunteers; data were acquired using an Orbiter-Siemens single-detector SPECT system. Using SPM, images were transformed spatially, smoothed (12mm), and the data were compared on a voxel-by-voxel basis with t-tests. RESULTS: There were significant rCBF reductions in AD patients relative to controls involving regions predicted a priori to be affected in AD, namely the left temporal and parietal neocortices, and the right posterior cingulate gyrus (p<0.05, corrected for multiple comparisons). DISCUSSION: The location of rCBF reductions in AD subjects in our study is consistent with the deficits detected in previous functional imaging studies of AD using higher-resolution devices. This suggests the potential usefulness of using SPM for the analysis of data acquired with single-detector SPECT systems, despite the limited sensitivity and spatial resolution of such equipment.
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Enfermedad de Alzheimer/fisiopatología , Mapeo Encefálico/métodos , Circulación Cerebrovascular/fisiología , Tomografía Computarizada de Emisión de Fotón Único/métodos , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Estudios de Casos y Controles , Interpretación Estadística de Datos , Estudios de Factibilidad , Femenino , Humanos , Masculino , Radiofármacos , Exametazima de Tecnecio Tc 99mAsunto(s)
Células de la Médula Ósea/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/cirugía , Trasplante de Células Madre Hematopoyéticas/métodos , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/cirugía , Exametazima de Tecnecio Tc 99m , Humanos , Masculino , Persona de Mediana Edad , Cintigrafía , Radiofármacos , Resultado del TratamientoRESUMEN
BACKGROUND AND PURPOSE: Reduced resting global cerebral blood flow has been previously detected in association with heart failure (HF), but it is not clear whether there are brain regions that could be specifically affected by those brain perfusion deficits. The authors used a fully automated, voxel-based image analysis method to investigate, across the entire cerebral volume, the presence of resting regional cerebral blood flow (rCBF) abnormalities in HF patients compared to healthy controls. METHODS: rCBF was evaluated with 99mTc-single-photon emission computed tomography in 17 HF patients (New York Heart Association functional class II or III) and 18 elderly healthy volunteers. Voxel-based analyses of rCBF data were conducted using the statistical parametric mapping software. RESULTS: Significant rCBF reductions in HF patients relative to controls (P<.05, corrected for multiple comparisons) were detected in 2 foci, encompassing, respectively, the left and right precuneus and cuneus and the right lateral temporoparietal cortex and posterior cingulated gyrus. In the HF group, there was also a significant direct correlation between the degree of cognitive impairment as assessed using the Cambridge Mental Disorders of the Elderly Examination and rCBF on a voxel cluster involving the right posterior cingulate cortex and precuneus, located closely to the site where between-group rCBF differences had been identified. CONCLUSIONS: These preliminary findings indicate that posterior cortical areas of the brain may be particularly vulnerable to brain perfusion reductions associated with HF and suggest that functional deficits in these regions might be relevant to the pathophysiology of the cognitive impairments presented by HF patients.
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Encéfalo/diagnóstico por imagen , Gasto Cardíaco Bajo/diagnóstico por imagen , Circulación Cerebrovascular/fisiología , Radiofármacos , Exametazima de Tecnecio Tc 99m , Tomografía Computarizada de Emisión de Fotón Único , Anciano , Gasto Cardíaco Bajo/fisiopatología , Estudios de Casos y Controles , Trastornos del Conocimiento/fisiopatología , Femenino , Giro del Cíngulo/irrigación sanguínea , Giro del Cíngulo/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Lóbulo Occipital/irrigación sanguínea , Lóbulo Occipital/diagnóstico por imagen , Lóbulo Parietal/irrigación sanguínea , Lóbulo Parietal/diagnóstico por imagen , Lóbulo Temporal/irrigación sanguínea , Lóbulo Temporal/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único/métodosRESUMEN
Typical (TPP) and atypical (APP) perfusion patterns (PP) may be seen in ictal SPECT of patients with temporal lobe epilepsy (TLE). APP may pose problem in the lateralization of the epileptogenic zone (EZ). We aimed to investigate predictive variables for the occurrence of TPP and APP. Fifty-one TLE patients were submitted to successful anterior-mesial temporal lobectomy. Univariate (UVA) and multivariate (MVA) analysis were performed upon clinical data, distribution of interictal spikes, and ictal chronology of seizures. From MVA, a final predictive model (FPM) was determined to better predict TPP and APP. Forty patients showed TPP (78.5%) and 11 patients APP (21.5%). Accuracy of ictal SPECT was higher in the unilateral (UIS) than in the bilateral (BIS) interictal spikes group (P = 0.05). FPM showed that patients exhibiting BIS, with shorter proportion of the electrographic seizure occurring after completion of tracer injection, and longer clinical than EEG seizure duration had more APP (P = 0.003). Generalized tonic-clonic seizures did not result in more APP. We concluded that analysis of ictal SPECT in TLE requires the knowledge of TPP and APP, the distribution of interictal spikes on temporal lobes and the ictal chronology of seizures. BIS showed that beyond a more complex epileptogenicity and seizure propagation, they may also lead to APP.
Asunto(s)
Electroencefalografía , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/fisiopatología , Lateralidad Funcional/fisiología , Lóbulo Temporal/fisiopatología , Tomografía Computarizada de Emisión de Fotón Único , Adolescente , Adulto , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Modelos Logísticos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico , Análisis Multivariante , Pruebas Neuropsicológicas , Radiofármacos , Estudios Retrospectivos , Exametazima de Tecnecio Tc 99m , Factores de TiempoRESUMEN
PURPOSE: Periodic lateralised epileptiform discharges (PLEDs) can be seen associated to nonconvulsive status epilepticus (NCSE), although their pathophysiological meaning remains questionable. Functional neuroimaging has suggested that, in this setting, PLEDs may indeed be an ictal pattern. In this report we describe perfusional changes in a patient with AIDS, PLEDs and NCSE. METHODS: A 37-year-old man with AIDS, cryptococcosis and recurrent epileptic seizures was admitted. After initial treatment, he remained comatose, and had MRI and serial EEG recordings performed. Technetium-99m-ethyl cysteinate dimer (99mTc-ECD) SPECT scans were also obtained, before and after continuous benzodiazepine infusion. RESULTS: EEG disclosed PLEDs over the right fronto-polar region while MRI revealed meningeal thickening and scattered unspecific findings. SPECT revealed marked focal hyperperfusion overlapping the areas with PLEDs, both resolved after continuous midazolam infusion and clinical improvement. CONCLUSIONS: This report demonstrates association of PLEDs, NCSE, and focal hyperperfusion on SPECT, additionally supporting the concept of PLEDs as an ictal pattern. Considering that status epilepticus may eventually not be detected by conventional approaches alone, we advocate the use of functional neuroimaging to assess suspected patients with impaired consciousness.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Electroencefalografía , Hiperemia/etiología , Periodicidad , Estado Epiléptico/fisiopatología , Adulto , Lateralidad Funcional/fisiología , Humanos , Masculino , Radiofármacos , Exametazima de Tecnecio Tc 99m , Tomografía Computarizada de Emisión de Fotón ÚnicoRESUMEN
OBJECTIVE: To evaluate (99m)Tc-HMPAO leukocyte scintigraphy as an investigation for inflammatory bowel disease (IBD). STUDY DESIGN: Scintigraphy was performed in 95 children undergoing investigation for IBD in a tertiary Gastroenterology Department. Diagnosis was based on conventional investigations including small bowel barium contrast radiology (BCR), upper gastrointestinal endoscopy (UGIE), colonoscopy, and endoscopic biopsy (the "gold standards"). IBD was confirmed in 73 (57 Crohn's disease; 10 ulcerative colitis; 6 indeterminate colitis) and excluded in 22 (controls). Scintigraphy was (1) evaluated as a screening test, (2) compared with individual conventional tests, (3) assessed for each gut segment. RESULTS: Screening test: sensitivity 0.75 (95% CI, 0.63-0.85), specificity 0.82 (95% CI, 0.59-0.94), PPV 0.93, NPV 0.5. Comparison with BCR: sensitivity 0.87 (95% CI, 0.72-0.96), specificity 0.57 (95% CI, 0.39-0.73), PPV 0.69, NPV 0.2. Comparison with UGIE: specificity 0.9 (95% CI, 0.79-0.96), NPV 0.13 (sensitivity and PPV unavailable). Comparison with colonoscopy: sensitivity 0.57 (95% CI, 0.41-0.73), specificity 0.71 (95% CI, 0.54-0.85), PPV 0.71, NPV 0.42. Comparison with biopsies paralleled that with endoscopy. False negatives were especially common (NPV< or =0.2) in the proximal gut. CONCLUSIONS: (99m)Tc-HMPAO leukocyte scintigraphy should not be relied on as a screening test for IBD because false negative results are common. This method is especially unreliable at detecting disease in the proximal gut.