Search

Objective: This study aimed to present a new possibility to create radio-opaque implant material for craniomaxillofacial reconstruction., Materials and Methods: The test disks made of the own compound of polyethylenes with addiction of 2, 4, and 6 % of weight TiO 2 was investigated for cytotoxicity [each group 15 disks respectively]. Next, computed tomography of the disks was performed in environment of muscle and fat. Hardness, tensile modulus and strength, and compressive modulus and strength were tested too., Results: Deterioration of mechanical properties of the composites containing titanium dioxide was observed [hardness, tensile modulus and strength, compressive modulus and strength, respectively: 56.7 ± 1.6 shore D, 354 ± 52, 22.5 ± 1.3, 21.8 ± 1.1, and 2995 ± 327 MPa as addiction of 2 % TiO 2 ; 52.0 ± 0.9 shore D, 347 ± 66, 18.0 ± 0.7, 14.2 ± 0.9, and 1396 ± 477 MPa as 4 % TiO 2 ; 51.3 ± 1.3 shore D, 316 ± 9, 17.4 ± 0.2, 13.6 ± 0.6, and 1100 ± 144 MPa as 6 % TiO 2 added]. The test disks revealed no cytotoxicity effect on human osteoblasts. The new material presents mild radio-opacity which was enough to observe the implant in relation to fat and muscle, but with no visible effect of beam hardening., Conclusion: In view of the performed tests, the polyethylene enriched by titanium dioxide seems to be a proper material to consider manufacturing of craniomaxillofacial implants., Clinical Relevance: Maxilloafacial surgery is still looking for new implantologic materials. The proposed one is a new way to manufacture an implant visible in computed tomography which does not interfere with its shape in radiological examination and makes it possible to observe the surrounding soft tissues.

The aim of this study is to compare magnetic resonance imaging (MRI) with computed tomography (CT) for visualization of an orbital alloplastic prosthesis made of ultra-high-molecular-weight polyethylene (UHMW-PE) both in vitro and in vivo. A study of 15 test implants from UHMW-PE visualized in vitro in CT and MRI and an in vivo visualization in a patient who suffered from orbital injury and underwent reconstructive surgery is presented. The postsurgery MRI showed the UHMW-PE material clearly, with no significant artifacts. The surrounding tissues could be satisfactorily evaluated. The CT scans did not present the graft material. Both techniques were sufficient tools for in vitro evaluation of the shape and measurement of the prosthesis.

The goal was to optimize dynamic T1 imaging for functional MRI (fMRI) examinations. For each of the 10 healthy subjects T1 3D gradient echo sequence (GRE) sequences were provided immediately after administration of blood pool contrast agent then every 2 h when subjects performed block finger tapings. Dynamic T1 fMRI is sensitive to detect cortical activations up to 6 h after BPCA administration. fMRI should be conducted within 2 h of CA administration, which is enough time for a typical fMRI experiment procedure., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Background: At present, endothelial dysfunction is best assessed in vivo with measurement of flow-mediated dilatation (FMD) with Doppler ultrasound scanning. This test, however, does not account for the subject's age and is uncomfortable for patients. The aim of the study was to compare a new test for endothelium function assessment using hand exercise load., Methods: The study group comprised 31 male patients with type 1 diabetes and 72 healthy men as controls. The subjects in both groups were subdivided into three age groups: 18-30 (subgroup A), 31-45 (subgroup B), and 46-60 (subgroup C) years. FMD of the brachial artery with induction of hand ischemia was conducted in all the subjects. Afterwards, an originally designed test using standardized hand exercise with the use of a training device was performed., Results: In the youngest group of type 1 diabetes patients the effect of hand ischemia on brachial artery diameter was greater than in the two older age subgroups: baseline artery diameter increased by 0.23 +/- 0.11 mm (5.7%), 0.19 +/- 0.09 mm (4.3%), and 0.13 +/- 0.02 mm (2.8%), respectively (P < 0.01). In the hand exercise test, artery diameter increased in the youngest subjects by 0.39 +/- 0.11 mm (9.5%) and in the two older groups by 0.26 +/- 0.07 mm (5.6%) and 0.18 +/- 0.09 mm (4.5%) (P < 0.05), respectively. In subgroups A, B and C, vasodilation after hand exercise test was greater by 67%, 30%, and 32% (P < 0.01), respectively, compared with the effect of the ischemic test. In the controls similar effects and relationship between ischemic and hand exercise tests were noted, however, with a smaller difference between the two tests., Conclusions: The hand exercise test results in a greater difference in vessel diameter before and after the test stimulus, which might substantially improve its feasibility. The hand exercise test could be a useful alternative tool for endothelial function assessment, especially in type 1 diabetes subjects.

Unlabelled: Pelvic organ prolapse is one of the most common disorders and it concerns over 50% of women over the age of fifty who gave birth., Background: The purpose of this study was to establish a clinically useful protocol of MR investigation in the assessment of pelvic organs position changes during rest and in time of Velsalva test, Objective: The material includes 17 postmenopausal women (48- 59-years-old) who were examined due of lumbosacralis discopathy in MR division of USK 1 in Lodz since 2007. The examination was extended to pelvic organs imaging with the help of Velsalva test., Results: Having compared static and dynamic images of investigated group and results of reference lines measurements, we have found normal pelvic organ position comparing to the H line in case of 10 women, in case of 5 women there was just a small displacement--up to 2 cm under the H line--and in case of 2 other women 2 cm above the H line. We have also found substantial increase of P line length (over 25% during tenesmus) in women with pelvic floor disorders., Conclusion: Dynamic MR imaging proves extremely useful in evaluation of pelvic organs position changes during rest and in time of Velsalva test.

The structural abnormalities in brains of persons suffering from schizophrenia were noticed in neuropathological studies, pneumoencephalography, tomography and magnetic resonance imaging for a long time. The reduction of grey matter volume was present mainly in frontal and temporal lobes and also a decrease of total brain volume with an increase of ventricle volume was observed. The volumetric reduction of white matter was not observed. However, structural changes may not be present in each case and conventional MRI, even with high resolution images is not able to detect subtle changes which may have a functional significance. The new MRI techniques, e.g. magnetic transfer imaging (MTI), indicate the presence of changes in the white matter of schizophrenic's brains, which are not detectable by conventional MRI. MTI is based on decreasing of the signal intensity by the transfer of magnetization between saturated protons of water, bound to macromolecules of myelin and phospholipids in cell membranes and free water protons. This process may be used to estimate structural integrity of white and grey matter, to reveal the presence of subtle changes in brain tissue.

Unlabelled: The aim of the study is to evaluate the reliability of the diffusion-weighted vs. FLAIR MR imaging in the cases of hyper acute brain stroke., Material and Methods: CT and MR standard and diffusion images observed in 29 patients affected with early brain stroke and reference CT in all the patients. Reference CT was performed 3-5 days later in all patients., Results: The pre- and post-contrast CT in 23 patients did not reveal any brain lesions. In contrary to CT areas of pathologic high signal were visualized well in diffusion MR in 20 of these patients, which supported early diagnosis. Discrete hiperintense lesions of the same locations were seen also in the FLAIR MR imaging in 19 of them. In the 6 patients CT revealed only discrete hipodense areas, which were seen more pronounced in the FLAIR and diffusion MR imaging. In the 3 cases even the second CT did not reveal stroke., Conclusions: The diffusion MR imaging in patients suspected of acute brain stroke reveals ischemic lesions earlier and more clearly than FLAIR imaging, which discrete presented the same pathological areas.

Introduction: Magnetic resonance images [MRI] and their digital fusion with computed tomography [CT] data, observed in patients affected with facial injuries, are presented in this study., Material and Methods: The MR imaging of 12 posttraumatic patients was performed in the same plains as their previous CT scans. Evaluation focused on quality of the facial soft tissues depicting, which was unsatisfactory in CT. Using the own "Dental Studio" programme the digital fusion of the both modalities was performed., Results: Pathologic dislocations and injures of facial soft tissues are visualized better in MRI than in CT examination. Especially MRI properly reveals disturbances in intraorbital soft structures., Conclusions: MRI-based assessment is valuable in patients affected with facial soft tissues injuries, especially in case of orbita/sinuses hernia. Fusion CT/MRI scans allows to evaluate simultaneously bone structure and soft tissues of the same region.

Purpose: To evaluate the reliability of the mono- (SCT) and multisliced CT (MSCT) imaging and their post-processing reconstructions in the cases of orbital trauma., Material and Methods: the spiral monoslice (n=20) and spiral multisliced (n=5) CT studies were performed in patients suffered from orbits' injuries. CT data were reconstructed in the 2D and 3D mode. The CT original images and the 2D and 3D reconstructions were evaluated according to the quality of visualization of a pathological lesions. Surgery was the method of reference., Results: The reconstructed 3D images in 16 patients examined in SCT mode and in 5 patients examined in MSCT mode allowed to recognize properly the fracture. In the 13 patients SCT and in the 3 ones MSCT revealed the bone fragments and orbital soft tissues prolapse towards maxilla sinus; including the lower rectus muscle in 6 cases. In 1 patient evaluation of the 3D model allowed to exclude communication with intracranial space. The surgery correlated well with the source images and 2D/3D SCT and MSCT models. The diagnostic quality of the raw SCT vs MSCT images was evaluated as equal, but MSCT proved to be the better source for the post processing reconstruction, because of higher resolution and better smoothing., Conclusions: - Spiral CT 2D and 3D reconstructed images, especially generated from the MSCT, more clearly than the source data depict anatomical spatial relationships; - 2D/3D reconstructions revealed the position, course and displacement of a fractured fragments; thus it supports the surgery.

The aim of the study is to assess the new method of radiological imaging of the inner surface of a tracheobronchial tree in order to determine to what extend it can replace the standard bronchoscopy. The spiral CT examinations of 43 patients with hilar lung tumor in virtual mode had been reconstructed retrospectively and compared to the results of fiberoptic bronchoscopy. There was a significant correlation between both methods to reveal stenoses or occlusions of airway lumen. Virtual endoscopy turned out to be an unsatisfactory method in the visualisation of mucosal changes.

The aim of the study was to assess the quality of biliary tract imaging without cholangiographic contrast medium and to evaluate the usefulness of 3-D reformations in determination of ductal anatomic relationship. The spiral 5 mm CT liver scans were performed after a bolus of 150 ml i.v. contrast agent in 15 patients with a malignant obstructive jaundice. The biliary tract was separated from surrounding hepatic parenchyma with segmentation computer algorithm and then 3-D models were produced. In all the patients, both biliary anatomy and the localization and degree of segmental obstruction were visualized with satisfying quality. The 3-D sCT models of dilated biliary tract can be obtained without cholangiographic contrast agent and can clearly depict ductal anatomy and pathology.