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Purpose: This study evaluated maxillary sinus volume changes in military jet aircraft pilot candidates before and after the training program, in comparison with a control group, considering the effects of pressurization, altitude, and total flight hours, through multislice computed tomography. Materials and Methods: Fifteen fighter pilots were evaluated before initiating the training program and after the final approval. The control group consisted of 41 young adults who had not flown during their military career. The volumes of each maxillary sinus were measured individually before and at the end of the training program. Results: When comparing the initial and final volumes in the pilots, a statistically significant increase was observed both in the left and right maxillary sinuses. When evaluating the average total volume of the maxillary sinuses (i.e., the average volume of the right and left maxillary sinuses together), a significant increase in the volume of the maxillary sinuses was observed in the pilot group when compared to the control group. Conclusion: The maxillary sinus volumes in aircraft pilot candidates increased after the 8-month training program. This may be explained by changes in the gravitational force, the expansion of gas, and positive pressure from oxygen masks. This unprecedented investigation among pilots might lead to other investigations considering paranasal sinus alterations in this singular population.

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As doenças neurometabólicas hereditárias representam um desafio diagnóstico e precisam de classificações eficientes para sua compreensão. São um grupo de doenças raras, mas atingem pelo menos um a cada mil nascimentos. Algumas têm possibilidade terapêutica. Os quadros clínico e radiológico são variáveis e, às vezes, superponíveis, a depender da fase da doença. Por isso, observam-se na literatura vários tipos de classificações, algumas de difícil aplicação prática. O objetivo deste estudo é ilustrar a classificação das doenças neurometabólicas hereditárias baseada exclusivamente em achados radiológicos. Trata-se de um estudo retrospectivo a partir de exames de imagem do sistema nervoso central, particularmente de crianças, realizados em uma rede de hospitais. Todos os casos foram estudados por tomografia computadorizada multidetectores e/ou ressonância magnética, tendo sido avaliados por dois neurorradiologistas. Consideraram-se os casos com diagnóstico definitivo. A classificação propõe 10 subgrupos, de acordo com os achados radiológicos. Todos os casos estudados apresentaram, pelo menos, um desses achados. Na maioria dos casos observou-se mais de um achado, o que aumentou a especificidade e restringiu os diagnósticos diferenciais. Após avaliar os dados de literatura e os deste estudo, demonstra-se que é possível classificar as doenças neurometabólicas hereditárias pelo aspecto radiológico, o que favorece um diagnóstico definitivo.

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Intracranial calcifications, which are common in the daily routine of radiologists, can have a physiological or pathological origin. Determining the cause of intracranial calcifications can represent a challenge. The anatomical location, distribution, dimensions and morphology of such calcifications are important findings, which, in conjunction with the clinical history and age group, can facilitate the differential diagnosis. The aim of this pictorial essay is to demonstrate the different types of intracranial calcifications and their origins. The images evaluated were those stored in picture archiving and communication systems. All of the cases included were studied by computed tomography, magnetic resonance imaging, or both. We identified, classified, and described 64 types of intracranial calcifications.

Calcificações intracranianas fazem parte da rotina do médico radiologista, as quais podem ter origem fisiológica ou patológica. A diferenciação entre as calcificações pode representar um desafio. Localização anatômica, distribuição, dimensões e morfologia das calcificações são importantes achados que, associados a história clínica e faixa etária, podem ajudar no diagnostico diferencial. O objetivo deste estudo é demonstrar os diferentes tipos de calcificações intracranianas e suas origens. Foram avaliadas as imagens armazenadas no sistema de comunicação e arquivamento de imagens das unidades. Todos os casos inclusos foram estudados por tomografia computadorizada e/ou ressonância magnética. Foram encontrados 64 tipos de calcificações intracranianas, que foram classificadas e descritas.

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Obtaining accurate and reproducible estimates of internal shell volume is a vital requirement for studies into the ecology of a range of shell-occupying organisms, including hermit crabs. Shell internal volume is usually estimated by filling the shell cavity with water or sand, however, there has been no systematic assessment of the reliability of these methods and moreover no comparison with modern alternatives, e.g., computed tomography (CT). This study undertakes the first assessment of the measurement reproducibility of three contrasting approaches across a spectrum of shell architectures and sizes. While our results suggested a certain level of variability inherent for all methods, we conclude that a single measure using sand/water is likely to be sufficient for the majority of studies. However, care must be taken as precision may decline with increasing shell size and structural complexity. CT provided less variation between repeat measures but volume estimates were consistently lower compared to sand/water and will need methodological improvements before it can be used as an alternative. CT indicated volume may be also underestimated using sand/water due to the presence of air spaces visible in filled shells scanned by CT. Lastly, we encourage authors to clearly describe how volume estimates were obtained.

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New research on assessing neuropsychiatric manifestations of Alzheimer´s Disease (AD) involves grouping neuropsychiatric symptoms into syndromes. Yet this approach is limited by high inter-subject variability in neuropsychiatric symptoms and a relatively low degree of concordance across studies attempting to cluster neuropsychiatric symptoms into syndromes. An alternative strategy that involves dichotomizing AD subjects into those with few versus multiple neuropsychiatric symptoms is both consonant with real-world clinical practice and can contribute to understanding neurobiological underpinnings of neuropsychiatric symptoms in AD patients. The aim of this study was to address whether the number of neuropsychiatric symptoms (i.e., presence of few [≤2] versus multiple [≥3] symptoms) in AD would be associated with degree of significant gray matter (GM) volume loss. Of particular interest was volume loss in brain regions involved in memory, emotional processing and salience brain networks, including the prefrontal, lateral temporal and parietal cortices, anterior cingulate gyrus, temporo-limbic structures and insula. We recruited 19 AD patients and 13 healthy controls, which underwent an MRI and neuropsychiatric assessment. Regional brain volumes were determined using voxel-based morphometry and other advanced imaging processing methods. Our results indicated the presence of different patterns of GM atrophy in the two AD subgroups relative to healthy controls. AD patients with multiple neuropsychiatric manifestations showed more evident GM atrophy in the left superior temporal gyrus and insula as compared with healthy controls. In contrast, AD subjects with few neuropsychiatric symptoms displayed more GM atrophy in prefrontal regions, as well as in the dorsal anterior cingulate ad post-central gyri, as compared with healthy controls. Our findings suggest that the presence of multiple neuropsychiatric symptoms is more related to the degree of atrophy in specific brain networks rather than dependent on the global severity of widespread neurodegenerative brain changes.

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Neuroendocrine tumours are epithelial neoplasms with predominant neuroendocrine differentiation. The nasal cavity and paranasal sinuses are rare locations for neuroendocrine carcinomas, and only a few related papers have been published in the literature to date. Here we present the case of a 64-year-old male with neuroendocrine carcinoma of the sphenoid sinus, along with the main MRI findings.

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Acute aortic dissection is a life-threatening event in which prompt and correct diagnosis is associated with better outcomes. In most cases, there is chest or back pain. However, in rare cases, patients have little or no pain and other symptoms are more conspicuous at presentation. The autors reports the case of a 47-year-old female patient who sought medical attention for sudden-onset paraplegia. The physical examination was normal except for bilateral lower limb flaccid paralysis, with abolition of deep tendon reflexes and paraesthesia in both feet. Computed tomography showed aortic dissection, with partial thrombosis of the false lumen, starting after the emergence of the left subclavian artery and extending, toward the bifurcation of the aorta, to the left iliac artery. After cerebrospinal fluid drainage, the evolution was favorable.

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Developmental dysplasia of the hip (DDH) is one of the most common congenital orthopedic anomalies. Ultrasound examination employing the Graf method is used to diagnose DDH. We conducted a retrospective cross-sectional study of 222 neonatal patients (140 females and 82 males) submitted to ultrasound examination of the right and left hips between January of 2009 and May of 2011. The mean age was 5.0 days. The patients were grouped by laterality, mean alpha (α) and beta (ß) angles (in degrees), and hip type (as determined by the Graf classification). The data collected were statistically correlated. Mean α angle values were higher in males than in females, as well as being higher for right hips than for left hips (p < 0.001). In contrast, mean ß angle values were lower in males than in females, as well as being lower for right hips than for left hips (p < 0.001). Type Ia hips (i.e., mature hips) predominated in both genders and on both sides, having been found in 82.32% of the examinations of males and in 71.09% of those of females. The right hip was classified as type Ia in 78.38% of the examinations, and the left hip was classified as type Ia in 72.07%. Type IIa hips (i.e., immature hips) were found in 12.8% of the examinations of males and in 20% of those of females. The right hip was classified as type IIa in 13.96% of the examinations, and the left hip was classified as type IIa in 20.72%. The remaining hip types were less common. We emphasize the importance of ultrasound as a standard method of screening for DDH.

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The focal calcification or ossification of the ligamentum flavum is a rare cause of thoracic myelopathy and most often occurs among individuals of Japanese descent. It is rare in other ethnic groups and in individuals below the age of 50. It is most often described at the lower thoracic level, being uncommon in the lumbar region and rare in the cervical region. Here, we present the case of a 44-year-old White female patient who sought medical attention with an eight-month history of paraesthesia of the lower limbs and progressive difficulty in walking. The clinical profile, together with computed tomography and nuclear magnetic resonance imaging of the spine, led to a diagnosis of compressive thoracic myelopathy due to ossification of the ligamentum flavum in the thoracic and lumbar spine. The patient underwent laminectomy and dissection of some of the affected ligamentum flavum, without any intraoperative complications. After three months of clinical follow-up, the patient had progressed favorably, having no sensory complaints and again becoming ambulatory.

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Omental infarction is a rare cause of acute abdominal pain, and the cause of omental infarction itself remains unknown. The diagnosis of omental infarction is occasionally made intra-operatively, because it is poorly known and presents no specific clinical features. Therefore omental infarction should always be considered in the differential diagnosis of abdominal inflammatory processes, mainly those affecting the right lower quadrant. The increasing use of computed tomography in cases of acute abdomen has facilitated the diagnosis of omental infarction in the pre-operative period. Here, we present the case of a 36-year-old, overweight female patient with clinical symptoms of acute abdomen. Computed tomography of the abdomen revealed indications of omental infarction. The patient was treated conservatively with analgesics and a nonsteroidal anti-inflammatory. The clinical evolution was favorable.