219 resultados para 110320 Radiology and Organ Imaging


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OBJECTIVE: To find out whether conventional periapical radiographs can be used to determine the risk of creating an oroantral communication (OAC) while performing periapical surgery on maxillary premolars and molars. STUDY DESIGN: One hundred thirteen periapical radiographs of maxillary premolars and molars with periapical radiolucencies indicating chronic apical periodontitis were retrospectively analyzed and classified. The surgery reports were evaluated for occurrence of perforation of the maxillary sinus and postoperative complications. RESULTS: Perforation of the sinus membrane (also referred to as the Schneiderian membrane) occurred in 12 cases (9.6%). Exposure of the membrane without rupture occurred in 15 cases (12%). It was found that the distance between the apex or the periapical lesion and the sinus floor did not serve as a predictor of a possible sinus membrane rupture. On the other hand, if the radiograph showed a distinct distance between the lesion and the sinus floor, there was an 82.5% probability that OAC would not occur. Additionally, a blurred radiographic outline of the periapical lesion did not indicate an increased risk of sinus membrane rupture. CONCLUSION: Conventional periapical radiographs cannot be used as predictors for perforation of the maxillary sinus during periapical surgery. However, radiographs with a specific distance between the periapical lesion and the sinus floor point toward a very low risk of accidental sinus perforation during periapical surgery.

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OBJECTIVE: To report clinical and diagnostic imaging features, and outcome after surgical treatment of ventral intraspinal cysts in dogs. STUDY DESIGN: Retrospective study. ANIMALS: Dogs (n=7) with ventral intraspinal cysts. METHODS: Clinical signs, magnetic resonance imaging (MRI) findings and surgical findings of 7 dogs and histologic findings (1 dog) with intraspinal cysts associated with the intervertebral disc were reviewed. RESULTS: Ventral intraspinal cyst is characterized by: (1) clinical signs indistinguishable from those of typical disc herniation; (2) an extradural, round to oval, mass lesion with low T1 and high T2 signal intensity on MRI, compatible with a liquid-containing cyst; (3) cyst is in close proximity to the intervertebral disc; and (4) MRI signs of disc degeneration. Although the exact cause is unknown, underlying minor disc injury may predispose to cyst formation. CONCLUSION: Intraspinal cysts have clinical signs identical to those of disc herniation. Given the close proximity of the cyst to the corresponding disc and the similarity of MRI findings to discal cysts in humans, we propose the term "canine discal cyst" to describe this observation. CLINICAL RELEVANCE: Discal cysts should be considered in the differential choices for cystic extradural compressing lesions.

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PURPOSE: It has been shown that some primary human tumours and their metastases, including prostate and breast tumours, overexpress gastrin-releasing peptide (GRP) receptors. Bombesin (BN) is a neuropeptide with a high affinity for these GRP receptors. We demonstrated successful scintigraphic visualisation of BN receptor-positive tumours in preclinical studies using the radiolabelled BN analogue [(111)In-DTPA-Pro(1),Tyr(4)]BN. However, the receptor affinity as well as the serum stability of this analogue leave room for improvement. Therefore new (111)In-labelled BN analogues were synthesised and evaluated in vitro and in vivo. METHODS AND RESULTS: The receptor affinity of the new BN analogues was tested on human GRP receptor-expressing prostate tumour xenografts and rat colon sections. Analogues with high receptor affinity (low nM range) were selected for further evaluation. Incubation in vitro of GRP receptor-expressing rat CA20948 and human PC3 tumour cells with the (111)In-labelled analogues resulted in rapid receptor-mediated uptake and internalisation. The BN analogue with the best receptor affinity and in vitro internalisation characteristics, Cmp 3 ([(111)In-DTPA-ACMpip(5),Tha(6),betaAla(11),Tha(13),Nle(14)]BN(5-14)), was tested in vivo in biodistribution studies using rats bearing GRP receptor-expressing CA20948 tumours, and nude mice bearing human PC3 xenografts. Injection of (111)In-labelled Cmp 3 in these animals showed high, receptor-mediated uptake in receptor-positive organs and tumours which could be visualised using planar gamma camera and microSPECT/CT imaging. CONCLUSION: With their enhanced receptor affinity and their rapid receptor-mediated internalisation in vitro and in vivo, the new BN analogues, and especially Cmp 3, are promising candidates for use in diagnostic molecular imaging and targeted radionuclide therapy of GRP receptor-expressing cancers.

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OBJECTIVES: To evaluate pain and swelling during the first week after periapical surgery and its relation to patient age, gender, oral hygiene, and smoking. STUDY DESIGN: One hundred two patients (31 men and 71 women) with a mean age of 40.2 years underwent periapical surgery. Age, gender, and oral hygiene and cigarette smoking before and during the postoperative course were noted. Pain and swelling scores were recorded on a descriptive 4-point scale at 2, 6, and 12 hours after surgery, and each day thereafter for 1 week. The data were statistically evaluated for significant differences. RESULTS: The highest intensity of pain occurred during the first 48 hours, and swelling peaked on the second postoperative day. Patient age and gender had no significant effect on postoperative symptoms (P > .05). Patients with poor oral hygiene before surgery presented greater pain and swelling during the first postsurgical hours, and smokers before surgery also suffered more pain. The number of cigarettes smoked in the postoperative period and oral hygiene after surgery had no effect on pain or inflammation (P > .05). CONCLUSIONS: Periapical surgery caused little pain and moderate swelling during the first 2 days after the intervention; these findings were more distinct in patients with poor oral hygiene before surgery and in smokers.

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Major progress has recently been made in the neuro-imaging of stroke as a result of improvements in imaging hardware and software. Imaging may be based on either magnetic resonance imaging (MRI) or computed tomography (CT) techniques. Imaging should provide information on the entire vascular cervical and intracranial network, from the aortic arch to the circle of Willis. Equally, it should also give information on the viability of brain tissue and brain hemodynamics. CT has the advantage in the detection of acute hemorrhage whereas MRI offers more accurate pathophysiological information in the follow-up of patients.

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OBJECTIVES: To compare the outcome of arthroscopic lysis and lavage of TMJ with internal derangement of Wilkes stages II, III, IV, and V. STUDY DESIGN: Arthroscopic lysis and lavage was performed in 45 TMJ of 39 patients with internal derangement. The cases were divided into 4 groups corresponding to Wilkes stages II, III, IV, and V. Two parameters were compared pre- and postoperatively: pain and mouth opening. Statistical significance was determined using the chi(2) test. RESULTS: Overall success rate was 86.7% (Wilkes stage II 90.9%, Wilkes stage III 92.3%, Wilkes stage IV 84.6%, Wilkes stage V 75%). There were no statistically significant differences between the success rates for Wilkes stages II, III, IV, and V. CONCLUSION: Arthroscopic lysis and lavage should be performed as a standard operation for internal derangement of the TMJ after failure of conservative treatment in all Wilkes stages.

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Non-invasive documentation methods such as surface scanning and radiological imaging are gaining in importance in the forensic field. These three-dimensional technologies provide digital 3D data, which are processed and handled in the computer. However, the sense of touch gets lost using the virtual approach. The haptic device enables the use of the sense of touch to handle and feel digital 3D data. The multifunctional application of a haptic device for forensic approaches is evaluated and illustrated in three different cases: the representation of bone fractures of the lower extremities, by traffic accidents, in a non-invasive manner; the comparison of bone injuries with the presumed injury-inflicting instrument; and in a gunshot case, the identification of the gun by the muzzle imprint, and the reconstruction of the holding position of the gun. The 3D models of the bones are generated from the Computed Tomography (CT) images. The 3D models of the exterior injuries, the injury-inflicting tools and the bone injuries, where a higher resolution is necessary, are created by the optical surface scan. The haptic device is used in combination with the software FreeForm Modelling Plus for touching the surface of the 3D models to feel the minute injuries and the surface of tools, to reposition displaced bone parts and to compare an injury-causing instrument with an injury. The repositioning of 3D models in a reconstruction is easier, faster and more precisely executed by means of using the sense of touch and with the user-friendly movement in the 3D space. For representation purposes, the fracture lines of bones are coloured. This work demonstrates that the haptic device is a suitable and efficient application in forensic science. The haptic device offers a new way in the handling of digital data in the virtual 3D space.

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PURPOSE: To evaluate the diagnostic accuracy of in situ postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) in the detection of primary traumatic extra-axial hemorrhage. MATERIALS AND METHODS: Thirty forensic neurotrauma cases and 10 nontraumatic controls who underwent both in situ postmortem cranial MSCT and MR imaging before autopsy were retrospectively reviewed. Both imaging modalities were analyzed in view of their accuracy, sensitivity, and specificity concerning the detection of extra-axial hemorrhage. Statistical significance was calculated using the McNemar test. kappa values for interobserver agreement were calculated for extra-axial hemorrhage types and to quantify the agreement between both modalities as well as MRI, CT, and forensics, respectively. RESULTS: Analysis of the detection of hemorrhagic localizations showed an accuracy, sensitivity, and specificity of 89%, 82%, and 92% using CT, and 90%, 83%, and 94% using MRI, respectively. MRI was more sensitive than CT in the detection of subarachnoid hemorrhagic localizations (P = 0.001), whereas no significant difference resulted from the detection of epidural and subdural hemorrhagic findings (P = 0.248 and P = 0.104, respectively). Interobserver agreement for all extra-axial hemorrhage types was substantial (CT kappa = 0.76; MRI kappa = 0.77). The agreement of both modalitites was almost perfect (readers 1 and 2 kappa = 0.88). CONCLUSION: CT and MRI are of comparable potential as forensic diagnostic tools for traumatic extra-axial hemorrhage. Not only of forensic, but also of clinical interest is the observation that most thin blood layers escape the radiological evaluation.

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SUMMARY: Multimodal imaging was performed in Rasmussen Encephalitis (RE) during episodes of complex-partial and focal motor status epilepticus including independent component analysis of BOLD-fMRI, arterial spin labeling perfusion imaging and diffusion tensor imaging. The active epileptic network and topographically independent brain areas showed regional hyperperfusion and progressive atrophy. The results suggest that hyperperfusion outside of the epileptic network represent active inflammation in RE and the imaging protocol presented here, allows assessing thereby the disease activity non-invasively.

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BACKGROUND: Percutaneous closure of patent foramen ovale (PFO) is generally performed using intra-procedural guidance by transoesophageal (TEE) or intracardiac (ICE) echocardiography. While TEE requires sedation or general anaesthesia, ICE is costly and adds incremental risk, and both imaging modalities lengthen the procedure. METHODS: A total of 825 consecutive patients (age 51 +/- 13 years; 58% male) underwent percutaneous PFO closure solely under fluoroscopic guidance, without intra-procedural echocardiography. The indications for PFO closure were presumed paradoxical embolism in 698 patients (95% cerebral, 5% other locations), an embolic event with concurrent aetiologies in 47, diving in 51, migraine headaches in 13, and other reasons in 16. An atrial septal aneurysm was associated with the PFO in 242 patients (29%). RESULTS: Permanent device implantation failed in two patients (0.2%). There were 18 procedural complications (2.2%), including embolization of the device or parts of it in five patients with successful percutaneous removal in all cases, air embolism with transient symptoms in four patients, pericardial tamponade requiring pericardiocentesis in one patient, a transient ischaemic attack with visual symptoms in one patient, and vascular access site problems in seven patients. There were no long-term sequelae. Contrast TEE at six months showed complete abolition of right-to-left shunt via PFO in 88% of patients, whereas a minimal, moderate or large residual shunt persisted in 7%, 3%, and 2%, respectively. CONCLUSIONS: This study confirms the safety and feasibility of percutaneous PFO closure without intra-procedural echocardiographic guidance in a large cohort of consecutive patients.

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The first trimester of pregnancy is the time during which organogenesis takes place and tissue patterns and organ systems are established. In the second trimester the fetus undergoes major cellular adaptation and an increase in body size, and in the third trimester organ systems mature ready for extrauterine life. In addition, during that very last period of intrauterine life there is a significant increase in body weight. In contrast to the postnatal endocrine control of growth, where the principal hormones directly influencing growth are growth hormone (GH) and the insulin-like growth factors (IGFs) via the GH-IGF axis, fetal growth throughout gestation is constrained by maternal factors and placental function and is coordinated by growth factors. In general, growth disorders only become apparent postnatally, but they may well be related to fetal life. Thus, fetal growth always needs to be considered in the overall picture of human growth as well as in its metabolic development.

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Various treatment options for deep cartilage defects are presently available. The efficacy of bone marrow stimulation with microfracture, of mosaicplasty and of various autologous chondrocyte implantation (ACI) techniques has been subject to numerous studies recently. Magnetic resonance imaging (MRI) has gained a major role in the assessment of cartilage repair. The introduction of high-field MRI to clinical routine makes high resolution and three-dimensional imaging readily available. New quantitative MRI techniques that directly visualize the molecular structure of cartilage may further advance our understanding of cartilage repair. The clinical evaluation of cartilage repair tissue is a complex issue, and MR imaging will become increasingly important both in research and in clinical routine. This article reviews the clinical aspects of microfracture, mosaicplasty, and ACI and reports the recent technical advances that have improved MRI of cartilage. Morphological evaluation methods are recommended for each of the respective techniques. Finally, an overview of T2 mapping and delayed gadolinium-enhanced MR imaging of cartilage in cartilage repair is provided.

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Modern cross-sectional imaging techniques are being increasingly implemented in forensic pathology. In order to assess the practicability of such a method, namely post-mortem multislice computed tomography (MSCT) in cases of fatal cut and stab injuries, 12 corpses underwent such an examination prior to forensic autopsy. The questions regarding detection of foreign bodies, wound channels, skeletal and organ injuries, as well as the cause of death were addressed at MSCT and autopsy. The results of the two techniques revealed that post-mortem MSCT a useful tool in the assessment of such injuries.