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Concept: Tomographic reconstruction

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Central odontogenic fibroma (COF) is a rare benign tumor that accounts for 0.1% of all odontogenic tumors. A case of COF (simple type) of the mandible in a four-year-old boy is described in this report. The patient showed asymptomatic swelling in the right inferior border of the lower jaw for one week. A panoramic radiograph showed a poorly-defined destructive unilocular radiolucent area. Cone-beam computed tomography showed expansion and perforation of the adjacent cortical bone plates. A periosteal reaction with the Codman triangle pattern was clearly visible in the buccal cortex. Since the tumor had destroyed a considerable amount of bone, surgical resection was performed. No recurrence was noted.

Concepts: Bone, Oncology, Mandible, Tomographic reconstruction, Benign tumor, Tumor, Temporomandibular joint, Jaw

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Objective To compare initial brain computed tomography (CT) scans with follow-up CT scans at one year in children with congenital Zika syndrome, focusing on cerebral calcifications.Design Case series study.Setting Barão de Lucena Hospital, Pernambuco state, Brazil.Participants 37 children with probable or confirmed congenital Zika syndrome during the microcephaly outbreak in 2015 who underwent brain CT shortly after birth and at one year follow-up.Main outcome measure Differences in cerebral calcification patterns between initial and follow-up scans.Results 37 children were evaluated. All presented cerebral calcifications on the initial scan, predominantly at cortical-white matter junction. At follow-up the calcifications had diminished in number, size, or density, or a combination in 34 of the children (92%, 95% confidence interval 79% to 97%), were no longer visible in one child, and remained unchanged in two children. No child showed an increase in calcifications. The calcifications at the cortical-white matter junction which were no longer visible at follow-up occurred predominately in the parietal and occipital lobes. These imaging changes were not associated with any clear clinical improvements.Conclusion The detection of cerebral calcifications should not be considered a major criterion for late diagnosis of congenital Zika syndrome, nor should the absence of calcifications be used to exclude the diagnosis.

Concepts: Medical imaging, Tomographic reconstruction, Human brain, Cerebrum, Functional neuroimaging

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Major issues in the implementation of screening for lung cancer by means of low-dose computed tomography (CT) are the definition of a positive result and the management of lung nodules detected on the scans. We conducted a population-based prospective study to determine factors predicting the probability that lung nodules detected on the first screening low-dose CT scans are malignant or will be found to be malignant on follow-up.

Concepts: Cancer, Metastasis, Lung cancer, Cancer staging, Pneumonia, Tomographic reconstruction, Solitary pulmonary nodule, Medical test

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The study objective was to determine whether intravenous contrast administration for computed tomography (CT) is independently associated with increased risk for acute kidney injury and adverse clinical outcomes.

Concepts: Medical imaging, Radiography, Tomographic reconstruction, Acute kidney injury, Management, Contrast medium, Radiocontrast, Contrast

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We acquire the first experimental 3-D tomographic images with magnetic particle imaging (MPI) using projection reconstruction methodology, which is similar to algorithms employed in X-ray computed tomography. The primary advantage of projection reconstruction methods is an order of magnitude increase in signal-to-noise ratio (SNR) due to averaging. We first derive the point spread function, resolution, number of projections required, and the SNR gain in projection reconstruction MPI. We then design and construct the first scanner capable of gathering the necessary data for nonaliased projection reconstruction and experimentally verify our mathematical predictions. We demonstrate that filtered backprojection in MPI is experimentally feasible and illustrate the SNR and resolution improvements with projection reconstruction. Finally, we show that MPI is capable of producing three dimensional imaging volumes in both phantoms and postmortem mice.

Concepts: Medical imaging, Radiography, Tomographic reconstruction, Dimension, Euclidean space, Tomography, Virtopsy, Signal-to-noise ratio

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ABSTRACT Traumatic brain injury (TBI) is an important health issue with high prevalence. The most common type of TBI is mild TBI (MTBI). MTBI is known as a condition with self-limited symptoms; however, it could cause some structural abnormalities of brain and become complicated. Visible structural brain damage could have an important effect on recovery after MTBI, but the outcome is not fully understood. This study investigated the clinical course of MTBI patients with the existence of contusion in computed tomography (CT) imaging. Fifty patients with MTBI and simultaneous brain contusion in CT scan were enrolled according to specific exclusion criteria in 14 month. Patients were followed up for two weeks after their first arrival for neurosurgical interventions, decreased level of consciousness, and other neurological complications. Presence of neurological symptoms increased duration of hospital stay and number of CT scans. Forty-two percent of MTBI patients with contusion did not have any objective neurological signs. Fifty percent returned to the hospital with neurologic symptoms and signs. Leading causes were headache followed by seizure and dizziness. Rehospitalization was increased in the patients with altered level of consciousness. The size of brain contusion increased in two patients without further need for neurosurgical intervention. Contusion alone did not worsen the prognosis of patients in short-term follow-up and did not cause neurosurgical interventions.

Concepts: Brain, Traumatic brain injury, Tomographic reconstruction, Neurology, Post-concussion syndrome, Subdural hematoma, Neurotrauma, Head injury

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BACKGROUND: There are several methods that may be used to confirm the status of rib cartilage, such as physical examinations or chest radiography, for subjects with microtia. However, these methods are limited because of clinicians' inability to gain accurate information about the rib cartilage. We performed 3-dimensional chest computed tomography to preoperatively evaluate the accuracy of rib cartilage imaging. METHODS: A total of 37 patients preparing for auricular reconstruction using a rib cartilage graft underwent preoperative 3-dimensional rib cage computed tomography (3-D rib CT). The 3-D rib CT was performed in cases of secondary revisional reconstruction, those with a history of surgery using rib cartilage, in those with a history of trauma related to the rib cage, older patients with question of calcification of rib cartilage, or those with a suspected rib cartilage anomaly on physical examination. Preoperatively, the appropriateness of using the rib cartilage were evaluated. RESULTS: With the aid of the 3-D rib CT, successful autogenous auricular reconstruction was achieved in 36 patients. Framework fabrication in combination with a porous polyethylene implant and autogenous rib cartilage was performed in the remaining patient as planned preoperatively. By analyzing the 3-D rib CT image preoperatively, auricular reconstruction using a recycled rib cartilage graft with newly harvested rib cartilage was performed successfully in 13 of 14 secondary revisional cases. Based on preoperative CT images, modified surgical planning in terms of cartilage harvest and framework fabrication was needed in 8 of 11 patients who had a history of operation using rib cartilage and in 3 of 5 subjects with suspected rib cage anomalies on physical examination. Successful reconstruction was achieved using the modified surgical plan. CONCLUSIONS: A preoperative 3-D rib CT helps in surgical planning for autogenous auricular reconstruction for microtia, especially in patients with suspicious rib cartilage status.

Concepts: Hospital, Surgery, Medical imaging, Radiography, Tomographic reconstruction, Tomography, Physical examination, Human rib cage

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PURPOSE: This study prospectively assessed whether the presence of a bull’s-eye pattern of pancreatic-duct stones on multidetector computed tomography (MDCT) correlated with gene-mutation-associated pancreatitis (GMAP) and whether other signs suggestive of GMAP can be detected with MDCT. MATERIALS AND METHODS: Forty-seven patients with chronic calcific pancreatitis underwent genetic testing for CFTR, SPINK1 and PRSS1 mutations and an MDCT scan of the abdomen. Qualitative analysis assessed the presence or absence of pancreatic-duct stones with bull’s-eye appearance. Quantitative analysis included the number and maximum diameter of stones and the diameter of the main pancreatic duct. RESULTS: Fifteen of 47 patients (32%) were positive for gene mutations (GMAP patients). The bull’s-eye pattern was found in 10/15 patients (67%) with GMAP and in 4/32 (12%) patients with chronic pancreatitis not associated with GMAP (NGMAP; p<0.0001). The mean diameter of duct stones was 15 mm in patients with GMAP and 10 mm in patients with NGMAP (p<0.04). CONCLUSIONS: The presence of duct stones with a bull's-eye pattern correlates with GMAP. Duct stones with diameter ≥15 mm are another sign suggestive of GMAP.

Concepts: Genetics, Pancreas, Medical imaging, Tomographic reconstruction, Qualitative research, Quantitative research, Pancreatitis, Pancreatic duct

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Objective: The purpose of this study was to describe computed tomography (CT) features of the ununited anconeal process and relate them with the following elbow dysplasia signs: medial coronoid disease, medial humeral condyle changes, osteoarthritis (OA), and radioulnar incongruence. Methods: Computed tomographic images of dogs older than six months with an ununited anconeal process were evaluated (n = 13). Ununited anconeal process features were described as being complete or incomplete, and the degree of displacement, volume, and presence of cysts and sclerosis were also evaluated. Medial coronoid disease was defined as an irregular medial coronoid process shape, presence of sclerosis and fragmentation. Medial humeral condyle changes were defined as subchondral bone flattening, lucencies, and sclerosis. Osteoarthritis was graded depending on the osteophytes size. Radioulnar incongruence was measured on a sagittal view at the base of the medial coronoid process. Results: Eleven elbows had a complete and two had an incomplete ununited anconeal process. All ununited anconeal processes had cystic and sclerotic lesions. Seven ununited anconeal processes were displaced and six were non-displaced. Mean ununited anconeal process volume was 1.35 cm3 (0.61 cm³ - 2.08 cm³). Twelve elbows had signs of medial coronoid disease (4 of them with a fragmented medial coronoid process), and one elbow did not show any evidence of medial coronoid disease. Ten elbows had medial humeral condyle changes. One elbow had grade 1 OA, seven elbows had grade 2, and five elbows grade 3. All elbows had radioulnar incongruence: three elbows had a negative and 10 elbows had a positive radioulnar incongruence. Mean radioulnar incongruence was 1.49 mm (0.63 mm - 2.61 mm). Computed tomographic findings were similar in the majority of the elbows studied: complete ununited anconeal processes with signs of medial coronoid disease, positive radioulnar incongruence, high grade of OA, sclerotic medial humeral condyle changes, and large ununited anconeal process volumes. Clinical significance: Incomplete small ununited anconeal process volumes could be associated with a lower incidence of medial coronoid disease or medial humeral condyle changes. We recommend performing preoperative CT of elbows with an ununited anconeal process to evaluate concurrent lesions.

Concepts: Tomographic reconstruction, Humerus, Elbow, Tomography, Second grade, Brachialis muscle, Brachioradialis, Coronoid process of the ulna

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To report the impact of computerized tomography (CT) based radiotherapy (RT) on heterotopic ossification (HO) outcomes.

Concepts: Tomographic reconstruction, Trigraph, Heterotopic ossification