Top PDF Low-Field Magnetic Resonance Imaging of Canine Hydrocephalus

Low-Field Magnetic Resonance Imaging of Canine Hydrocephalus

Low-Field Magnetic Resonance Imaging of Canine Hydrocephalus

The aim of presented study was to evaluate selected surface spine coil, and low- field magnetic resonance (MR) selected sequences in diagnosing hydrocephalus in dogs. This paper discusses 19 dogs (14 canine patients with hydrocephalus and 5 healthy dogs), of five breeds, subjected to low-field magnetic resonance imaging (MRI) of hydrocephalus. Area of the lateral ventricles and brain were examined in dogs with hydrocephalus using low-field MRI (at 0.25 Tesla). The MRI of FSE REL, SE, FLAIR, STIR, 3D HYCE, T3DT1, GE STIR 3D and 3D SHARC sequences with an indication of the most effective sequences are described. Additionally, coils for MR were compared, and models for infusion anesthesia were described. As a result of performed study all estimated sequences were diagnostically useful. However, spinal coil No. 2 (ESAOTE) was the most optimal for examining and positioning the cranium.
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Endometriose pélvica: comparação entre imagens por ressonância magnética de baixo campo (0,2 T) e alto campo (1,5 T)

Endometriose pélvica: comparação entre imagens por ressonância magnética de baixo campo (0,2 T) e alto campo (1,5 T)

OBJECTIVE: To compare low-field (0.2 T) with high-field (1.5 T) magnetic resonance imaging in the assessment of pelvic endometriosis and adenomyosis. MATERIALS AND METHODS: Twenty-seven female patients with clinically suspected endometriosis were prospectively evaluated by means of high-field and low-field magnetic resonance imaging. The reading of the images was performed by a single radiologist, initiating by the low-field, followed by the high-field images. High-field magnetic resonance imaging was utilized as the golden-standard. RESULTS: Among the 27 patients included in the present study, 18 (66.7%) had some type of lesion suggesting the presence of endometriosis demonstrated at high-field images. In 14 of these patients the diagnosis was correctly established by low-field magnetic resonance imaging. Endometriomas, tubal lesions, and endometriotic foci > 7 mm identified at the high-field images were also identified at low-field images with 100% accuracy, sensitivity and specificity. Among the nine patients diagnosed with adenomyosis by high-field images, eight were correctly diagnosed by low-field images with 88.9% accuracy, specificity and sensitivity. CONCLUSION: Low-field magnetic resonance imaging demonstrated a low sensitivity in the detection of small endometriotic foci, high sensitivity in the detection of endometriomas and large endometriotic foci, and high accuracy in the detection of adenomyosis when compared with high-field magnetic resonance imaging.
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Arq. NeuroPsiquiatr.  vol.63 número1

Arq. NeuroPsiquiatr. vol.63 número1

Magnetic resonance imaging (MRI) equipments of high field, dedicated specifically to experimental uses, have been used to study the hydrocephalus in vivo of small rats carriers of congenital hydrocephalus. In this experiment the MRI of 1,0 T (the same used to investi- gate neurological diseases in humans is evaluated as an imaging method to study in vivo the size of the ventri- cles of hydrocephalic rats of the race Wistar.

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Condromalácia de patela: comparação entre os achados em aparelhos de RM de alto e baixo campo magnético

Condromalácia de patela: comparação entre os achados em aparelhos de RM de alto e baixo campo magnético

2 to be significantly overestimated. Lateral facet has presented a reasonable agreement index and disagreement index was not significant. Medial ridge has presented a reasonable agreement index and disagreement index has showed to be underestimated. CONCLUSION: The STIR sequence versus TSE T2 SPIR sequence has presented the higher agreement index. High-grade lesions are better characterized by low-field-strength magnetic resonance imaging equipment sequences. Areas of increased signal intensity make difficult the study of the patella medial facet cartilage in low-field-strength equipment. Keywords: Magnetic resonance imaging; Skeletal – appendicular; Knee; Comparative study; Equipments;
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Arq. NeuroPsiquiatr.  vol.63 número1

Arq. NeuroPsiquiatr. vol.63 número1

Magnetic resonance imaging (MRI) equipments of high field, dedicated specifically to experimental uses, have been used to study the hydrocephalus in vivo of small rats carriers of congenital hydrocephalus. In this experiment the MRI of 1,0 T (the same used to investi- gate neurological diseases in humans is evaluated as an imaging method to study in vivo the size of the ventri- cles of hydrocephalic rats of the race Wistar.

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A guide for functional magnetic resonance imaging

A guide for functional magnetic resonance imaging

It is important to consider that for fMRI the nominal spatial resolution is defined by the FOV in k-space (or voxel size in the image space). However, its effective spatial resolution can be considerably lower due to the physiological spread of the hemodynamic response and the specific vascular weighting of the fMRI sequence [232]. The typical fMRI voxel size is 3-4 mm, although with higher field magnets (7T) a size of 500 microns or less may be readily achieved [100]. The spatial resolution of PET is typically ≥4–5 mm, being limited by the positron-electron annihilation range and the size of the gamma ray detectors [234]. The NIRS spatial resolution is low (10–20 mm) and limited mainly by the strong dispersion and attenuation of IR photons, which also restricts the depth of cortex that can be imaged within a banana-shaped region connecting the NIRS optodes [100]. The resolution in EEG and MEG is also limited to > 10–20 mm because unique reconstructions of dipoles are not possible from scalp based measurements of electrical or magnetic distributions. Unlike EEG, MEG does not suffer from scalp recordings being spatially distorted by heterogeneous electrical conduction paths within the brain/skull [100].
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Multiparametric MRI and Image analysis

Multiparametric MRI and Image analysis

the sagittal plane and, posteriorly, in quadrants from apex to base. Slices were further cut into microscopic sections of 3-5µm and stained with Haematoxylin and Eosin. ECE was defined as tu- mor cell growth into the extraprostatic tissue and subclassified as: 1) focal ECE when involving only a few glands or a tumor involving less than one high power (40X) field in one or two sections or 2) stablished ECE when a more extensive spread was seen beyond the prostatic edge (16). SVI was de- fined as tumor infiltration of the muscular wall of the seminal vesicles. Lymph nodes were processed as a whole with posterior differentiation of nod- ules from fat. The pathological T-stage (pT) was defined according to the TNM classification.
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Prostate Cancer: The Role of Multiparametric Magnetic Resonance Imaging

Prostate Cancer: The Role of Multiparametric Magnetic Resonance Imaging

At our institution, we perform mp-MRI on a 1.5 T body scanner (Magneton Avanto; Siemens) with a 33 mT/m maximum attainable amplitude using an eight channel PPA. The study of the pelvis includes an axial turbo spin-eco T1WI imaging for nodal disease and postbiopsy intraglandular hemorrhage detection (5 mm; gap 1.0 mm; repetition time [TR] 450 ms; eco time [TE] 7.9 ms; FOV 40 cm; matrix 269 x 384), and also an axial Blade T2WI with fat saturation (FS) (5 mm; gap 1.0 mm; TR 4760 ms; TE 120 ms; FOV 36 cm; number of blades 20) which improves nodal disease and bone metastasis detection. With regard to the prostate gland study, we perform a set of axial, coronal and sagital high-resolution T2WI (3 mm; gap 0.6 mm; TR 4000 ms; TE 103 ms; FOV 20 cm; matrix 310 x 320). An axial DWI is performed with b factors of 50, 800, 1000 and 1200 s/mm2 (3.5 mm; gap 0.7 mm; TR 5100 ms; TE 88 ms; FOV 45 cm; matrix 150 x 192). The DCE-MRI is performed with an axial fat-saturated 3D Vibe T1W MR sequence (26 slabs; slice oversampling 23%, dist factor 20%; 3.5 mm; TR 4.84 ms; TE 1.69 ms; FOV 26 cm; matrix 138 x 192), after bolus injection of gadoterate meglumine, with a dose of 0.2 mmol/ kg of body weight.
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VANISHING WHITE MATTER DISEASE : A CASE REPORT

VANISHING WHITE MATTER DISEASE : A CASE REPORT

INTRODUCTION: Vanishing white matter disease (VWM) is one of the most prevalent inherited childhood leucoencephalopathies. The disease is variably called Myelinopathia Centralis Diffusa. Childhood ataxia and diffuse central nervous system hypomyelination are the common findings. The disease is characterized by chronic progressive and episodic deterioration with ataxia, spasticity and optic atrophy. 1 VWM is caused by mutation in any of the five genes encoding the

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ADVANCES IN CLOG STATE MONITORING FOR USE IN AUTOMATED REED BED INSTALLATIONS

ADVANCES IN CLOG STATE MONITORING FOR USE IN AUTOMATED REED BED INSTALLATIONS

Unilateral magnet arrangements have been explored for this application in the laboratory, including using the stray field of an arrangement of four magnets and bar magnet (Hughes-Riley et al. 2014b; Hughes-Riley et al. 2014c under review; Hughes-Riley et al. 2014d). Unilateral designs are preferred over an internal volume design as they are less disruptive to the flow-path of effluent and cannot become physically clogged by gravel. The four-magnet sensor showed promise in a lab environment, however further development (unpublished) to deploy the sensor into a reed bed has been problematic. Signal intensity is not sufficient to take T 2 eff measurements in a timely manner. Another issue is that in its
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Ultrasound-guided facet block to low back pain: a case report

Ultrasound-guided facet block to low back pain: a case report

is the bony crest of the sacrum as a hyperechoic signal with a bone shadow just below. The transducer is moved cephalward until a hyperechoic structure is displayed. This structure corresponds to the subarachnoid space of L5---S1 and is reflective of the CSF in the ventral dura mater. In a more cephalic level, it is possible to view other hyperechoic signal, corresponding to the spinous process of L5. The guid- ance of the transducer to a more cephalic region allows us to identify all the spinous processes, correlating them with the previously made skin marks. When the transducer reaches the desired site for the injection into the facet, the device is rotated 90 degrees. With this maneuver, three shadows of the lumbar vertebra are depicted. The most superficial layer is the spinous process; the facet joint is immediately below; and the transverse process is located below and laterally to the spinous process and articular facet.
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Fetal eye movements on magnetic resonance imaging.

Fetal eye movements on magnetic resonance imaging.

Of the 88 axial sequences, 20 (23.5%) were excluded due to insufficient image quality (see Exclusion criteria), as well as 12 of the 51 coronal sequences (23.5%), and four of the 30 sagittal sequences (13.3%) that were intentionally acquired for the Figure 1. Examples of coronal, a , sagittal, c , and axial, d , images at 34+4GW, 21+1GW, and 26 GW respectively and the lines drawn to measure bulb positions and to calculate bulb deviations. a Coronal frame of a dynamic MR sequence. A horizontal line at the level of the most caudal part of the hyperintense nasal choanae is drawn, A. Vertical line at the vertical axis of both lenses are drawn separately, B and C, craniocaudally and perpendicularly to the horizontal line A. b Schematic drawing of the eyeball on two sequential frames with the bulb radius on these frames forming an isoscles triangle and allowing the calculation of the angle d of bulb deviation. (Details concerning the calculation of the angles of bulb deviations between sequential coronal frames can be found in the Methods section.) c Sagittal frame of a dynamic MR sequence. Two lines were marked as references to indicate the hypointense roof of the orbit, E, and the longest axis of the sagittally depicted lens, F. The angle e enclosed by these two lines was measured and differences between the angle e on sequential frames were calculated. d shows an axial frame of a dynamic MR sequence. Three lines were marked as references to indicate the intracranial midline, G, and the longest axis of the axially depicted lens in each eye, H and I. The angle enclosed by the line through the longest axis of the lens and the intracranial midline was measured on each side, a and b.
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Radiol Bras  vol.41 número1

Radiol Bras vol.41 número1

For the magnetic resonance urography studies, three-dimensional half-Fourier acquisition single-shot turbo spin echo (3D-HASTE) T2-weighted sequences with fat saturation were performed with 2800 ms repetition time, 1080 ms echo time, 512 matrix, 2.0 s acquisition time, and block thickness (slab) ranging between 7 cm and 10 cm to include the whole urinary tract and bladder, at different angles in relation to the transverse axis to obtain anterior, lateral (sagittal) and oblique views. The breathhold acquisition time was short (2.0 s) and, consequently, was well toler- ated by the patients. This sequence is the same utilized in magnetic resonance cho- langiography.
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Radiol Bras  vol.50 número6

Radiol Bras vol.50 número6

Nipple discharge is a common symptom in clinical practice, representing the third leading breast complaint, after pain and lumps. It is usually limited and has a benign etiology. The risk of malignancy is higher when the discharge is uniductal, unilateral, sponta- neous, persistent, bloody, or serous, as well as when it is accompanied by a breast mass. The most common causes of pathologic nipple discharge are papilloma and ductal ectasia. However, there is a 5% risk of malignancy, mainly ductal carcinoma in situ. The clinical examination is an essential part of the patient evaluation, allowing benign nipple discharge to be distinguished from suspicious nipple discharge, which calls for imaging. Mammography and ultrasound should be used together as irst-line imaging methods. However, mammography has low sensitivity in cases of nipple discharge, because, typically, the lesions are small, are retroareolar, and contain no calciications. Because the reported sensitivity and speciicity of ultrasound, it is important to use the correct technique to search for intraductal lesions in the retroareolar region. Recent studies recommend the use of magnetic reso- nance imaging in cases of suspicious nipple discharge in which the mammography and ultrasound indings are normal. The most common magnetic resonance imaging inding is non-mass enhancement. Surgery is no longer the only solution for patients with suspicious nipple discharge, because short-time follow-up can be safely proposed.
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Dement. neuropsychol.  vol.11 número4

Dement. neuropsychol. vol.11 número4

A review of the literature (Table 1) published between January 2010 and 2017 was performed through searches on the electronic databases PubMed/MEDLINE (http://www.ncbi.nlm.nih.gov/pubmed/), Institute for Scientiic Information Web of Knowledge (http://www. isiknowledge.com) and EMBASE (http://www.embase. com), using the following terms: “structural neuroim- aging”, “cerebrovascular”, “vascular dementia”, “vascular cognitive impairment” “aging”, “difusion tensor imaging”, “DTI”, “MRI”, “VBM”, “molecular neuroim- aging”, “SPECT” and “PET” search. Firstly, the complete abstract was read, with the irst paper selection. A second selection included the full reading of the papers. Articles were included if they focused on clinical and therapeutic applications of novel neuroimaging techniques in the assessment of cognitive symptoms of VCI-CVD-VaD. Although we designed a non-systematic review, article retrieval and selection were performed following the main recommendations of the Moose guidelines. 15
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Radiol Bras  vol.46 número2

Radiol Bras vol.46 número2

cations in 97 patients submitted to prostate biopsy, utilizing data collected by means of phone interviews, searching information about the onset of adverse effects, fever or hemorrhage up to 14 days after the procedure. After prophylactic antibiotic therapy with ciprofloxacin, all the patients were submitted to a same protocol of prostate biopsy including anesthesia by means of periprostatic neurovascular bundle block. The collection of 12 specimens from the whole prostate followed the standard procedure recommended by Brazilian College of Radiology and Imaging Diagnosis and by Brazilian Urology Society. Additional specimens were collected when there were focal lesions in the peripheral region or in the cases of saturation rebiopsy, when 18 specimens were collected.
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Technology Governance in Radiology The example of Magnetic Resonance Imaging

Technology Governance in Radiology The example of Magnetic Resonance Imaging

In a more recent report concerning Portugal health system, by the European Observatory on Health Systems and Policies and Nova School of Business and Economics, it is stat that Portugal does not have a tradition of HTA, with the exception of pharmaceutical products.. Since 1988 the Ministry of Health has authorized the procurement and installation of expensive medical technologies in the public and private sectors. In 1995, new legislation lifted the restrictions on computerized (axial) tomography (CT) and magnetic resonance imaging (MRI) scanners. There are currently no effective methods for regulating the distribution of health equipment in the private sector. Most expensive medical equipment (67%) is located in the private sector, which is more flexible and innovative and therefore outstrips the public sector in the acquisition of high-technology equipment. Hospitals contract with private clinics for the use of equipment, providing a strong incentive for this provision pattern to continue (Barros, Machado, and Simoes 2011).
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Atypical presentation of a common opportunistic infection in advanced AIDS

Atypical presentation of a common opportunistic infection in advanced AIDS

lymphoma, toxoplasmosis and tuberculoma. While less common lesions are pyogenic ab- scess, cysticercosis, and syphilitic gummas. In our case we had a very large lesion in the brain parenchyma with a CD4+ count of 63 cells/µL. We initially suspected PCNSL, following which we have done EBV PCR which was negative. Then we considered second differen- tial diagnosis of tuberculoma. This patient had features common to PCNSL and tuberculoma, namely, altered sensorium, memory distur- bance, irrelevant talk, raised ESR, heteroge- neous peripherally enhancing ill defined lesion and lymphocytic predominance in CSF. Though sterotactic brain biopsy would confirm the tissue diagnosis, due to risks associated with doing the procedure we did MR spectroscopy to identify an infective lesion. MRS done at the site of lesions showed a increased lipid peak and a decreased NAA peak with increased cho- line/creatine ratio 6 . MRS helps to identify lip-
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Arthroscopic acromioplasty: magnetic resonance imaging analysis of modifications in acromial morphology

Arthroscopic acromioplasty: magnetic resonance imaging analysis of modifications in acromial morphology

The Journal has limited space to publish numerous review and technique articles and these are usually solicited by the Review Article and Special Projects Editors. Authors must remember the Journal only publishes one review paper per issue, or about 12 per year. In a typical year, the Journal receives in excess of 200 review articles submitted in consideration for publication. Hence, the acceptance rate of review articles for the Journal is usually around 3%-4%. Authors considering submission of a review article are encouraged to read "What is the value of a systematic review? (J Shoulder Elbow Surg 23:1-2, 2014; http://dx.doi.org/10.1016/j.jse.2013.09.001)" to critically evaluate whether their submission may be suitable for publication in the journal. Please contact the Review and Special Projects Editor (T. Bradley Edwards, M.D.) via jsesedit@gmail.com outlining your proposed article. Video Technique Articles are acceptable but will be published only on the website.
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Rev. odonto ciênc.  vol.25 número1

Rev. odonto ciênc. vol.25 número1

Twenty-ive percent of the patients with JIA have alterations in TMJ. These patients present destruction of articular structures, which can lead to typical facial expressions (10), such as the “bird face” (6). This can result in facial de- formity such as asymmetry, micro and retrognathia (9), hypoplasy of the mandibular condyle, and consequent class II malocclusion, anterior open bite (4) and increased overjet (10). The morphologic facial feature is usually asso- ciated with the destruction of the mandibular condyle (11). The ultimate and dramatic consequence of the joint destruction is TMJ ankylosis and biting limitation (9). Although TMJ involvement in children with JIA is not uncommon, it rarely occurs at the early phase of the disease. The most reported symptoms are pain during activity and at rest, restriction of the maximal voluntary mouth opening, morning stiffness, TMJ crepitation (9) and mandible deviation (11), which are evidences of the internal TMJ degeneration. However, the clinical examination alone is not reliable for detecting TMJ degenerative processes (5). The image examinations such as computed tomography (CT) and magnetic resonance imaging (MRI) are important to assess the condition of bones and soft structures of the TMJ. TMJ can be uni- or bilaterally affected, in several stages of the disease, with associated pain or with complete absence of symptoms. This has contributed to the dificulties of clinical identiication of JIA for many years. The present article describes the computed tomography (CT) and the magnetic resonance (MRI) images of a 12-year-old patient who presented JIA with TMJ involvement.
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