Maxillary sinus volumetric changes in jet aircraft pilots: A multislice computed tomography pilot study.

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.

Classificação das doenças neurometabólicas hereditárias baseada em aspectos radiológicos: ensaio iconográfico.

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.

Classification and clinical significance of intracranial calcifications: a pictorial essay.

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.

Gastropod shell size and architecture influence the applicability of methods used to estimate internal volume.

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.

Cortical brain volume abnormalities associated with few or multiple neuropsychiatric symptoms in Alzheimer's disease.

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.

Sphenoid sinus neuroendocrine carcinoma.

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.

Nosocomial rapidly growing mycobacterial infections following laparoscopic surgery: CT imaging findings.

OBJECTIVE: To identify the distribution and frequency of computed tomography (CT) findings in patients with nosocomial rapidly growing mycobacterial (RGM) infection after laparoscopic surgery. METHOD: A descriptive retrospective study in patients with RGM infection after laparoscopic surgery who underwent CT imaging prior to initiation of therapy. The images were analyzed by two radiologists in consensus, who evaluated the skin/subcutaneous tissues, the abdominal wall, and intraperitoneal region separately. The patterns of involvement were tabulated as: densification, collections, nodules (≥1.0 cm), small nodules (<1.0 cm), pseudocavitated nodules, and small pseudocavitated nodules. RESULTS: Twenty-six patients met the established criteria. The subcutaneous findings were: densification (88.5%), small nodules (61.5%), small pseudocavitated nodules (23.1 %), nodules (38.5%), pseudocavitated nodules (15.4%), and collections (26.9%). The findings in the abdominal wall were: densification (61.5%), pseudocavitated nodules (3.8%), and collections (15.4%). The intraperitoneal findings were: densification (46.1%), small nodules (42.3%), nodules (15.4%), and collections (11.5%). CONCLUSION: Subcutaneous CT findings in descending order of frequency were: densification, small nodules, nodules, small pseudocavitated nodules, pseudocavitated nodules, and collections. The musculo-fascial plane CT findings were: densification, collections, and pseudocavitated nodules. The intraperitoneal CT findings were: densification, small nodules, nodules, and collections. KEY POINTS: • Rapidly growing mycobacterial infection may occur following laparoscopy. • Post-laparoscopy mycobacterial infection CT findings are densification, collection, and nodules. • Rapidly growing mycobacterial infection following laparoscopy may involve the peritoneal cavity. • Post-laparoscopy rapidly growing mycobacterial intraperitoneal infection is not associated with ascites or lymphadenopathy.

Aortic dissection-induced acute flaccid paraplegia treated with cerebrospinal fluid drainage.

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.

Using the Graf method of ultrasound examination to classify hip dysplasia in neonates.

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.

Calcification of the ligamentum flavum in the thoracolumbar spine: an unusual cause of compressive myelopathy.

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.

Segmental omental infarction: an unusual cause of acute abdomen.

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.

Idiopathic sclerosing encapsulating peritonitis: an uncommon cause of intestinal obstruction.

Sclerosing encapsulating peritonitis (SEP), also called encapsulating peritonitis, is a rare and benign cause of intestinal obstruction of unknown etiology. Its onset may be acute or subacute although there are some reports with a two-month history. More commonly, this entity is secondary to chronic peritoneal dialysis, ventriculoperitoneal and peritoneovenous shunting, the use of ß-blockers and systemic lupus erythematous. Recurrent episodes of bacterial peritonitis, intestinal tuberculosis, sarcoidosis, familial Mediterranean fever, gastrointestinal cancer, liver transplantation, intra-abdominal fibrogenic foreign bodies, and luteinized ovarian thecomas are also related to SEP. The idiopathic presentation is more rare. Abdominal pain, nausea, vomiting, weight loss, malnutrition, and clinically palpable mass characterize the clinical features. Diagnosis is frequently made with gross findings during surgery, imaging workup and histopathology. The authors report the case of a 36-year-old male patient with a 10-day history of abdominal pain that was operated on because of intestinal obstruction. Diagnosis was made preoperatively and confirmed by the intraoperative findings and histopathology.

Treatment of resistant obsessive-compulsive disorder with ventral capsular/ventral striatal gamma capsulotomy: a pilot prospective study.

A subgroup of obsessive-compulsive disorder (OCD) patients remains refractory to conventional treatments. For them, a new stereotactic radiosurgery has been recently developed: the ventral capsular/ventral striatal (VC/VS) gamma capsulotomy. The authors aim to report efficacy and adverse events of VC/VS gamma capsulotomy. Five refractory OCD patients were selected. The authors assessed OCD, anxiety and depressive symptoms, and side effects pre- and postoperatively. Three patients (60%) met response criteria 48 months after surgery. Adverse effects were episodic and transient. Ventral capsular/ventral striatal gamma capsulotomy holds therapeutic promise, with few adverse effects.

Increased rates of white matter hyperintensities in late-onset bipolar disorder.

OBJECTIVES: Magnetic resonance imaging (MRI) studies have reported an increased frequency of white matter hyperintensities (WMH) in association with late-onset (LO) depression, and this has supported the notion that vascular-related mechanisms may be implicated in the pathophysiology of LO mood disorders. Recent clinical studies have also suggested a link between LO bipolar disorder (LO-BD) and cerebrovascular risk factors, but this has been little investigated with neuroimaging techniques. In order to ascertain whether there could be a specific association between WMH and LO-BD, we directly compared WMH rates between LO-BD subjects (illness onset >or= 60 years), early-onset BD subjects (EO-BD, illness onset <60 years), and elderly healthy volunteers. METHODS: T2-weighted MRI data were acquired in LO-BD subjects (n = 10, age = 73.60 +/- 4.09), EO-BD patients (n = 49, age = 67.78 +/- 4.44), and healthy subjects (n = 24, age = 69.00 +/- 7.22). WMH rates were assessed using the Scheltens scale. RESULTS: There was a greater prevalence of WMH in LO-BD patients relative to the two other groups in the deep parietal region (p = 0.018) and basal ganglia (p < 0.045). When between-group comparisons of mean WMH scores were conducted taking account of age differences (ANCOVA), there were more severe scores in LO-BD patients relative to the two other groups in deep frontal and parietal regions, as well as in the putamen (p < 0.05). CONCLUSIONS: Our results provide empirical support to the proposed link between vascular risk factors and LO-BD. If extended in future studies with larger samples, these findings may help to clarify the pathophysiological distinctions between bipolar disorder emerging at early and late stages of life.

Multisite fMRI reproducibility of a motor task using identical MR systems.

PURPOSE: To estimate between-scanner functional MRI (fMRI) reproducibility in a multisite study. MATERIALS AND METHODS: A total of five identical 1.5T MR systems were used to repeatedly scan five subjects while performing a finger tapping task. A two-way (scanners, subjects) random effects analysis of variance (ANOVA) was used to estimate between-scanner and between-subject variability on two outcome variables: task-related mean blood oxygenation level dependent (BOLD) signal change and volume of activation within a motor region-of-interest (ROI). RESULTS: Between-scanner variability of fMRI data accounted for a small proportion of the total variation in the BOLD signal change (8.34%, P = 0.114) and volume of activation (5.46%, P = 0.203). Between-subject variation accounted for more than half of the total variation for both measurements (57.17% and 54.46%, respectively, P < 0.01). CONCLUSION: These results support the feasibility of multisite studies using identical scanner systems.

Insight and regional brain volumes in schizophrenia.

We have investigated the relationship between insight impairment and regional brain volumes (gray and white matter) in schizophrenia using voxel-based morphometry (VBM). Fifty patients with schizophrenia were evaluated using the Scale for Unawareness of Mental Disorders. Magnetic resonance images were acquired, segmented and spatially normalized using optimized VBM routines. No significant inverse correlations were detected between insight impairment and gray or white matter volumes in the prefrontal region (where significant findings had been predicted a priori), or in any other brain areas. Our results do not support previous hypotheses suggesting a relationship between frontal lobe atrophy and impaired insight in patients with schizophrenia.

Association between major depressive symptoms in heart failure and impaired regional cerebral blood flow in the medial temporal region: a study using 99m Tc-HMPAO single photon emission computerized tomography (SPECT).

BACKGROUND AND PURPOSE: Depressive symptoms are frequently associated with heart failure (HF), but the brain mechanisms underlying such association are unclear. We hypothesized that the presence of major depressive disorder (MDD) emerging after the onset of HF would be associated with regional cerebral blood flow (rCBF) abnormalities in medial temporal regions previously implicated in primary MDD, namely the hippocampus and parahippocampal gyrus. METHOD: Using 99mTc-SPECT, we measured rCBF in 17 elderly MDD-HF patients, 17 non-depressed HF patients, and 18 healthy controls, matched for demographic variables. Group differences were investigated with Statistical Parametric Mapping. RESULTS: Significant rCBF reductions in MDD-HF patients relative to both non-depressed HF patients and healthy controls were detected in the left anterior parahippocampal gyrus and hippocampus (ANOVA, p=0.008 corrected for multiple comparisons) and the right posterior hippocampus and parahippocampal gyrus (p=0.005 corrected). In the overall HF group, there was a negative correlation between the severity of depressive symptoms and rCBF in the right posterior hippocampal/parahippocampal region (p=0.045 corrected). CONCLUSIONS: These findings are consistent with the notion that the medial temporal region is vulnerable to brain perfusion deficits associated with HF, and provide evidence that such functional deficits may be specifically implicated in the pathophysiology of MDD associated with HF.

Evaluation of the agreement between 3-dimensional ultrasonography and magnetic resonance imaging for fetal lung volume measurement.

OBJECTIVE: The purpose of this study was to assess the agreement between 3-dimensional ultrasonography (3DUS) and magnetic resonance imaging (MRI) for lung volumetry in fetuses with and without abnormalities associated with lung hypoplasia. METHODS: Fifty-nine singleton pregnancies were evaluated. Cases were separated into groups 1 and 2, according to the presence or absence of malformations associated with lung hypoplasia, respectively. Fetal lung volume was calculated by the Virtual Organ Computer-Aided Analysis (VOCAL) program of the 3DUS and the MRI. In both groups, measurements performed with all VOCAL angles were compared among themselves and with those obtained by MRI. Bland-Altman tests and analysis of variance were used for this purpose. RESULTS: In groups 1 and 2, the mean lung volume obtained with each rotation angle of the VOCAL technique was significantly smaller than the mean volume calculated by MRI (P < .001), and the mean volume obtained with the 30 degrees rotation step was significantly smaller than those obtained with the other rotation steps of the VOCAL technique. Bland-Altman tests confirmed this underestimation and showed a broad 95% confidence interval when the VOCAL angles were compared with those of MRI and when the 30 degrees rotation step was compared with the other VOCAL steps. CONCLUSIONS: There was a substantial discrepancy between 3DUS and MRI and between the 30 degrees rotation step of the VOCAL technique and the other rotation angles, for lung volume measurement in fetuses with and without abnormalities associated with lung hypoplasia.

Rightward cerebral asymmetry in subtypes of schizophrenia according to Leonhard's classification and to DSM-IV: a structural MRI study.

Although well documented, brain structural abnormalities in schizophrenia are non-specific, and morphometric parameters show significant overlap between patients and healthy controls. Such inconsistencies in neuroimaging findings could represent different levels of severity along a single pathogenic process or distinct clinical and etiopathological psychoses within a schizophrenic spectrum. The aim of the present study was the investigation of distinct brain abnormalities in different subtypes of schizophrenia. Forty patients were classified according to DSM-IV and Leonhard's classifications. Psychopathology was assessed by the Positive and Negative Syndrome Scale (PANSS) and the Negative Symptom Rating Scale (NSRS). Patients were compared to 20 healthy volunteers on volumetric measures of cerebral structures (hemisphere, hippocampus and planum temporale) and ventricular-brain ratio (VBR) obtained by magnetic resonance imaging. Patients showed rightward asymmetry of cerebral hemispheres and increased VBR. Rightward asymmetry correlated with severity of negative symptoms and prevailed in the systematic forms of Leonhard, suggesting a distinct pattern of left hemisphere abnormality in this subgroup of psychoses. Increased VBR values showed a single normal distribution in the subgroups, indicating that ventricular enlargement is not restricted to a subgroup but is present to a certain degree in all cases.

31P-spectroscopy of frontal lobe in schizophrenia: alterations in phospholipid and high-energy phosphate metabolism.

Studies using 31P-magnetic resonance spectroscopy (MRS) reported on abnormalities in frontal lobe metabolism in schizophrenia. The most consistent findings were a reduction in the resonances of phosphomonoesters (PME) and/or increased phosphodiesters (PDE), which are, respectively, the precursors and the metabolites of membrane phospholipids, thus suggesting an accelerated phospholipid metabolism in the disease. Other studies reported increased high-energy phosphates (ATP-adenosine triphosphate and PCr-phosphocreatine) in schizophrenia, reflecting decreased use of energy in the frontal lobe. We investigated 53 schizophrenic patients (DSM-IV) and 35 healthy controls. Eighteen from these patients were drug nai;ve and the remaining 35 were drug-free for an average of 6 months. Phospholipid metabolism and high-energy phosphates were assessed in the left frontal lobe using 31P-MRS. Psychopathological evaluation was done with the Brief Psychiatric Rating Scale (BPRS) and the Negative Symptoms Rating Scale (NSRS). Neuropsychological evaluation was performed with the Wisconsin Card Sorting Test (WCST), Stroop Test and Wechsler Adult Intelligence Scale. Drug-nai;ve patients showed reduced PDE in the left frontal lobe compared to controls and to previously medicated patients (p<0.05). No differences among the three groups were found regarding the other spectroscopy parameters. In healthy controls, but not in schizophrenics, a negative (and probably physiological) correlation was found between PME and PDE (p<0.01). In schizophrenic patients, ATP was correlated with negative symptoms and with neuropsychological impairment (p<0.01). The lack of a correlation between PME and PDE, as well as the reduction of PDE in schizophrenia, suggest a disrupted phospholipid metabolism in the disease, albeit on a contrary direction of that reported in literature. The relationships of ATP with negative symptoms and neuropsychological deficit suggest an alteration of energetic demand in the frontal lobe of schizophrenic patients, which is in line with the hypofrontality hypothesis of the disease.