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La atresia de coana es una rara malformación congénita improbable de encontrar de forma bilateral en un adolescente o adulto. Hasta la fecha, no se ha descrito ningún caso de atresia bilateral en un adulto con una malformación asociada de cabeza y cuello que haya requerido tratamiento conjunto. El tratamiento de elección de la atresia de coana bilateral continúa siendo la cirugía endoscópica, con controversia en el uso intraoperatorio de mitomicina o la colocación de stents para evitar estenosis. Lo que no está claro es el orden de tratamiento y la simultaneidad del procedimiento si se asocian otras posibles patologías que tengan una indicación quirúrgica. Presentamos un caso clínico que cumple con todos estos requisitos.

Choanal atresia is a rare congenital malformation that is unlikely to be found bilaterally and is seldom diagnosed in adulthood. To date, no clinical case of bilateral atresia has been described with a head and neck malformation that requires surgical treatment in an adult. The preferred treatment is still endoscopic sinonasal surgery with discrepancies of the use or not of intraoperative topical mitomycin or the placement of stents to avoid restenosis. What is not clear is the order of treatment and simultaneity of the procedure with other possible associated pathologies that have a surgical indication. We present a clinical case that meets all these requirements.

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Objetivos: Valorar las variantes fisiológicas, anatómicas y lesiones benignas en estudios por tomografía computada por emisión de positrones (PET/TC) con Galio 68 (68Ga)-DOTATATE. Materiales y métodos: Se revisaron en forma retrospectiva los informes de PET/TC con 68Ga-DOTATATE y se seleccionaron aquellos en los cuales se mencionaran palabras en el reporte relacionadas a variantes anatómicas, fisiológicas y tumores benignos. El grado de captación del 68Ga-DOTATATE fue evaluado de forma cualitativa y cuantitativa mediante la medición del valor estandarizado de captación máximo (SUVmax). Se consignó la localización del hallazgo, el valor de SUVmax y la imagen morfológica por tomografía computada (TC). Todos los casos fueron controlados mediante evolución clínica y hallazgos imagenológicos. Resultados: De un total de 772 informes de PET/TC se obtuvo un total de 28 pacientes con 33 variantes o tumores benignos, 14 mujeres y 14 hombres con edad promedio de 63 años. Las captaciones se clasificaron en cuatro grupos: variantes anatómicas y/o fisiológicas (n = 15), dependientes de la actividad osteoblástica (n=4), dependientes de actividad inflamatoria (n = 10) y tumores benignos no neuro-endócrinos (n = 4). Discusión: Los receptores de somatostatina se localizan no sólo en el sistema neuroendócrino sino también en otros tejidos. Las variantes fisiológicas, anatómicas y tumores benignos que expresan estos receptores pueden inducir a un error diagnóstico. Conclusión: Las variantes fisiológicas y lesiones benignas (tumorales e inflamatorias) pueden captar 68Ga-DOTATATE ya que sus tejidos pueden expresar receptores de somatostatina. El análisis semiológico del componente tomográfico de este método de imágenes híbrido, permite la orientación diagnóstica, optimizando el rendimiento del estudio PET/TC.

Purpose: To evaluate the physiological, anatomical variants and benign lesions in positrón emission computed tomography (PET/CT) studies with 68Ga-DOTATATE. Materials and methods: We retrospectively reviewed PET/CT reports scanned with 68Ga-DOTATATE and selected those that contained words in the report related to anatomical, physiological variants and benign tumors. The degree of 68Ga-DOTATATE uptake was evaluated qualitatively and quantitatively by measuring the standarized uptake max value (SUVmax value). The anatomical location, SUVmax value and morphological CT image findings were recorded. All cases had clinical and imaging follow-up. Results: From a total of 772 PET/CT reports, 28 patients were obtained with 33 benign variants or tumors, 14 females and 14 males with a median age of 63 years. Uptake patterns were classified into four groups: anatomic and physiological variants (15), dependent on osteoblastic activity (4), dependent on inflammatory activity (10) and non-neuro-endocrine benign tumors (4). Discussion: Somatostatin receptors are overexpressed not only in the neuroendocrine system but also in other tissues. Physiological, anatomical variants and benign tumors expressing these receptors may be misleading. In the present work the frequency of this finding is 5.1%. Conclusion: Physiological variants and benign lesions (tumor and inflammatory) can accumulate 68Ga-DOTATATE since their tissues can express somatostatin receptors. The semiologic analysis of the tomographic component of this hybrid method enhances the diagnostic efficacy, optimizing PET/CT study performance.

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The developmental dysplasia of the hip (DDH), where the spectrum of deformity varies from a slight mismatch in the articular surfaces between the ilium and femur, which will bring a premature wear of the joint, until the situation more serious when the femoral head is out of the acetabulum, causing a host of disorders side as curvature of the spine, significant shortening of the limb deformities in the knee and the contralateral hip, as well as causing pain and loss of joint mobility mentioned. All this makes the spectrum of abnormalities in a person being disabled with a social and economic burden for the family and society. "Preventing" a clinical entity such as developmental dysplasia of the hip does not mean to anticipate the presentation, because children continue to be born with this problem, but to have a program for early detection and early treatment and thus prevent the occurrence. The goal of this study was to provide the medical community that timely tool for prevention. When diagnosed and treated in a timely and favorable prognosis qualified for motor function and quality of life.

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The main objective of the present study was to upgrade a clinical gamma camera to obtain high resolution tomographic images of small animal organs. The system is based on a clinical gamma camera to which we have adapted a special-purpose pinhole collimator and a device for positioning and rotating the target based on a computer-controlled step motor. We developed a software tool to reconstruct the target’s three-dimensional distribution of emission from a set of planar projections, based on the maximum likelihood algorithm. We present details on the hardware and software implementation. We imaged phantoms and heart and kidneys of rats. When using pinhole collimators, the spatial resolution and sensitivity of the imaging system depend on parameters such as the detector-to-collimator and detector-to-target distances and pinhole diameter. In this study, we reached an object voxel size of 0.6 mm and spatial resolution better than 2.4 and 1.7 mm full width at half maximum when 1.5- and 1.0-mm diameter pinholes were used, respectively. Appropriate sensitivity to study the target of interest was attained in both cases. Additionally, we show that as few as 12 projections are sufficient to attain good quality reconstructions, a result that implies a significant reduction of acquisition time and opens the possibility for radiotracer dynamic studies. In conclusion, a high resolution single photon emission computed tomography (SPECT) system was developed using a commercial clinical gamma camera, allowing the acquisition of detailed volumetric images of small animal organs. This type of system has important implications for research areas such as Cardiology, Neurology or Oncology.

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The main objective of the present study was to upgrade a clinical gamma camera to obtain high resolution tomographic images of small animal organs. The system is based on a clinical gamma camera to which we have adapted a special-purpose pinhole collimator and a device for positioning and rotating the target based on a computer-controlled step motor. We developed a software tool to reconstruct the target's three-dimensional distribution of emission from a set of planar projections, based on the maximum likelihood algorithm. We present details on the hardware and software implementation. We imaged phantoms and heart and kidneys of rats. When using pinhole collimators, the spatial resolution and sensitivity of the imaging system depend on parameters such as the detector-to-collimator and detector-to-target distances and pinhole diameter. In this study, we reached an object voxel size of 0.6 mm and spatial resolution better than 2.4 and 1.7 mm full width at half maximum when 1.5- and 1.0-mm diameter pinholes were used, respectively. Appropriate sensitivity to study the target of interest was attained in both cases. Additionally, we show that as few as 12 projections are sufficient to attain good quality reconstructions, a result that implies a significant reduction of acquisition time and opens the possibility for radiotracer dynamic studies. In conclusion, a high resolution single photon emission computed tomography (SPECT) system was developed using a commercial clinical gamma camera, allowing the acquisition of detailed volumetric images of small animal organs. This type of system has important implications for research areas such as Cardiology, Neurology or Oncology.

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The elevated plus-maze is an animal model used to study anxiety. In a second session, rats show a reduction in the exploratory behavior even when the two sessions are separated by intervals as large as 7 days. The aim of the present study was to investigate whether the reduction in the exploratory behavior is maintained after intervals larger than 7 days. Additionally, we aimed at investigating eventual correlations between behaviors in the plus-maze and activation of limbic structures as measured by Fos protein expression after the second session. Rats were tested for 5 min in the elevated plus-maze and re-tested 3, 9 or 33 days later. Other groups were tested only once. The rat brains were processed for immunohistochemical detection of Fos protein. The results show a decrease in the open arms exploration in the second trial with intervals of 3, 9 and 33 days. The expression of Fos protein in the piriform cortex, septal nucleus and paraventricular hypothalamic nucleus in the groups tested with intervals of 9 and 33 days were statistically different from the other groups. The alterations observed in exploratory behavior in the second session in the plus-maze did not correlate with Fos expression. In conclusion, although the specific test conditions were sufficient to evoke behavioral alterations in exploration in the elevated plus-maze, they were enough to induce significant Fos protein expression in piriform cortex, septal nucleus and thalamic and hypothalamic paraventricular nuclei but not in other areas such as dorsomedial nucleus of the hypothalamus and amygdala nuclei, known to be also active participants in circuits controlling fear and anxiety.

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Single-photon emission computed tomography (SPECT) is a non-invasive imaging technique, which provides information reporting the functional states of tissues. SPECT imaging has been used as a diagnostic tool in several human disorders and can be used in animal models of diseases for physiopathological, genomic and drug discovery studies. However, most of the experimental models used in research involve rodents, which are at least one order of magnitude smaller in linear dimensions than man. Consequently, images of targets obtained with conventional gamma-cameras and collimators have poor spatial resolution and statistical quality. We review the methodological approaches developed in recent years in order to obtain images of small targets with good spatial resolution and sensitivity. Multipinhole, coded mask- and slit-based collimators are presented as alternative approaches to improve image quality. In combination with appropriate decoding algorithms, these collimators permit a significant reduction of the time needed to register the projections used to make 3-D representations of the volumetric distribution of target's radiotracers. Simultaneously, they can be used to minimize artifacts and blurring arising when single pinhole collimators are used. Representation images are presented, which illustrate the use of these collimators. We also comment on the use of coded masks to attain tomographic resolution with a single projection, as discussed by some investigators since their introduction to obtain near-field images. We conclude this review by showing that the use of appropriate hardware and software tools adapted to conventional gamma-cameras can be of great help in obtaining relevant functional information in experiments using small animals.

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Single-photon emission computed tomography (SPECT) is a non-invasive imaging technique, which provides information reporting the functional states of tissues. SPECT imaging has been used as a diagnostic tool in several human disorders and can be used in animal models of diseases for physiopathological, genomic and drug discovery studies. However, most of the experimental models used in research involve rodents, which are at least one order of magnitude smaller in linear dimensions than man. Consequently, images of targets obtained with conventional gamma-cameras and collimators have poor spatial resolution and statistical quality. We review the methodological approaches developed in recent years in order to obtain images of small targets with good spatial resolution and sensitivity. Multipinhole, coded mask- and slit-based collimators are presented as alternative approaches to improve image quality. In combination with appropriate decoding algorithms, these collimators permit a significant reduction of the time needed to register the projections used to make 3-D representations of the volumetric distribution of target’s radiotracers. Simultaneously, they can be used to minimize artifacts and blurring arising when single pinhole collimators are used. Representation images are presented, which illustrate the use of these collimators. We also comment on the use of coded masks to attain tomographic resolution with a single projection, as discussed by some investigators since their introduction to obtain near-field images. We conclude this review by showing that the use of appropriate hardware and software tools adapted to conventional gamma-cameras can be of great help in obtaining relevant functional information in experiments using small animals.

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Se presenta una paciente de 51 años de edad y blanca que fue operada de Hallux Valgus del pie izquierdo con la técnica de McBride modificada y que evolutivamente se le diagnosticó un Sudeck y presentó una severa deformidad en garras de los dedos que le dificultaba la marcha. El objetivo fue lograr un pie plantígrado con la técnica quirúrgica de plastias tendinosas de los extensores y flexores de los dedos del pie y las artrodesis metatarsofalángicas. A través de un abordaje dorsal del pie se pudo realizar las plastias tendinosas y las artrodesis de las cinco articulaciones metatarsofalángicas. Su evolución fue satisfactoria y a las 12 semanas ya la paciente podia caminar y calzar zapatos cómodos, a las 20 semanas se le dio el alta definitiva.

It is presented a white female, 51-years-old patient that was operated on, by suffering from Hallux Valgus in the left foot, by means of McBride modified technique being later diagnosed a Sudeck and presented a severe deformity in claws of the fingers that complicated her to walk. The objective of this work was to achieve a plantigrade foot by putting into practice the tendinous plasties surgical technique of the extensors and flexores of the toes and the metatarsophalangeal arthrodesis. Through a dorsal approach of the foot could be carried out the tendinous plasties and the arthrodesis of the five metatarsophalangeal joints. Her evolution was satisfactory; 12 weeks later the patient could already walk and wear comfortable shoes and after 20 weeks she was finally discharged.

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