Bone SPECT-CT: An additional diagnostic tool for undiagnosed wrist pain.

Science.gov (United States)

Shirley, R A; Dhawan, R T; Rodrigues, J N; Evans, D M

2016-10-01

Diagnosis of wrist pain can be difficult to determine with clinical examination and conventional imaging techniques alone. Bone SPECT-CT (single-photon emission tomography with computerized tomography) is a hybrid imaging technique that overlays functional bone scintigraphy in tomographic/3D mode with conventional CT. Data from the two modalities are complementary; areas of abnormal bone metabolism can be localized with anatomical precision, hitherto lacking in conventional bone scans, while structural information from the CT scan further embellishes the diagnostic information. Over the last 6 years, one surgeon (David Evans) has used bone SPECT and later bone SPECT-CT as an additional line of investigation. This is a series of 21 consecutive patients with wrist pain that could not be diagnostically resolved with the usual combination of history, examination, and conventional imaging, and therefore underwent bone SPECT-CT. Clinical and imaging findings, management, and outcomes of these cases are discussed to explore the potential role of this hybrid functional modality in hand and wrist surgical practice. Copyright © 2016. Published by Elsevier Ltd.

Digital subtraction cerebral angiography by intraarterial injection: comparison with conventional angiography

International Nuclear Information System (INIS)

Brant-Zawadzki, M.; Gould, R.; Norman, D.; Newton, T.H.; Lane, B.

1983-01-01

For 4 months, a prototype digital subtraction system was used to obtain images of the cerebral vasculature after intraarterial contrast injections. In 12 instances, the intraarterial injections were recorded with both a digital subtraction unit and conventional direct magnification film-screen system. The digital subtraction and conventional film subtraction images were compared and graded for quality and information content by three skilled observers. In addition, quantitative measurements of contrast-detail performance and spatial resolution were obtained on both the digital system and the screen-film imaging chain. In a clinical setting, both the digital subtraction and conventional film-screen systems provided similar quality images and angiographic information. Contrast-detail curves demonstrated that digital subtraction angiography outperformed conventional film technique for low-contrast objects. Digital subtraction angiography also reduced the time required to obtain the angiogram, markedly reduced film cost, and lowered the contrast agent burden

Application of 2 mm thin-slice scanning with bone algorithm on conventional CT in diagnosis of the pulmonary diseases

International Nuclear Information System (INIS)

Zhang Xianheng; Li Xiuhua; Wang Fenghua

2004-01-01

Objective: To evaluate the value of 2 mm thin-slice conventional CT scan with bone algorithm in diagnosis and differential diagnosis in the pulmonary diseases. Methods: In total 135 cases of the pulmonary diseases were routinely scanned by conventional scan, 10 mm per slice, with standard algorithm, then the 2 mm thin-slice scan with bone algorithm was performed at the interested region of the lungs. Result: According to the comparative study of the CT signs between 10 mm slice scan with standard algorithm and 2 mm thin-slice scan with bone algorithm, the latter was better on displaying the pulmonary axial interstium, intralobular septum, subpleura lines, honeycombing, 2-5 mm nodulars and anomalies of bronchial wall. Conclusion: According to the study of 135 cases, 2 mm thin-slice scan with bone algorithm is superior to 10 mm slice scan with standard algorithm in demonstrating the pulmonary lesions. It has a similar value with high-resolution spiral CT in the diagnosis of the pulmonary solitary or diffuse nodules, pulmonary diffuse interstitial lesions and the lesions of the airway. It is practical and advisable in the community hospital

Automated bone removal in CT angiography: Comparison of methods based on single energy and dual energy scans

International Nuclear Information System (INIS)

Straten, Marcel van; Schaap, Michiel; Dijkshoorn, Marcel L.; Greuter, Marcel J.; Lugt, Aad van der; Krestin, Gabriel P.; Niessen, Wiro J.

2011-01-01

Purpose: To evaluate dual energy based methods for bone removal in computed tomography angiography (CTA) images and compare these with single energy based methods that use an additional, nonenhanced, CT scan. Methods: Four different bone removal methods were applied to CT scans of an anthropomorphic thorax phantom, acquired with a second generation dual source CT scanner. The methods differed by the way information on the presence of bone was obtained (either by using an additional, nonenhanced scan or by scanning with two tube voltages at the same time) and by the way the bone was removed from the CTA images (either by masking or subtracting the bone). The phantom contained parts which mimic vessels of various diameters in direct contact with bone. Both a quantitative and qualitative analysis of image quality after bone removal was performed. Image quality was quantified by the contrast-to-noise ratio (CNR) normalized to the square root of the dose (CNRD). At locations where vessels touch bone, the quality of the bone removal and the vessel preservation were visually assessed. The dual energy based methods were assessed with and without the addition of a 0.4 mm tin filter to the high voltage x-ray tube filtration. For each bone removal method, the dose required to obtain a certain CNR after bone removal was compared with the dose of a reference scan with the same CNR but without automated bone removal. The CNRD value of the reference scan was maximized by choosing the lowest tube voltage available. Results: All methods removed the bone completely. CNRD values were higher for the masking based methods than for the subtraction based methods. Single energy based methods had a higher CNRD value than the corresponding dual energy based methods. For the subtraction based dual energy method, tin filtration improved the CNRD value with approximately 50%. For the masking based dual energy method, it was easier to differentiate between iodine and bone when tin filtration

A temporal subtraction method for thoracic CT images based on generalized gradient vector flow

International Nuclear Information System (INIS)

Miyake, Noriaki; Kim, H.; Maeda, Shinya; Itai, Yoshinori; Tan, J.K.; Ishikawa, Seiji; Katsuragawa, Shigehiko

2010-01-01

A temporal subtraction image, which is obtained by subtraction of a previous image from a current one, can be used for enhancing interval changes (such as formation of new lesions and changes in existing abnormalities) on medical images by removing most of the normal structures. If image registration is incorrect, not only the interval changes but also the normal structures would be appeared as some artifacts on the temporal subtraction image. In a temporal subtraction technique for 2-D X-ray image, the effectiveness is shown through a lot of clinical evaluation experiments, and practical use is advancing. Moreover, the MDCT (Multi-Detector row Computed Tomography) can easily introduced on medical field, the development of a temporal subtraction for thoracic CT Images is expected. In our study, a temporal subtraction technique for thoracic CT Images is developed. As the technique, the vector fields are described by use of GGVF (Generalized Gradient Vector Flow) from the previous and current CT images. Afterwards, VOI (Volume of Interest) are set up on the previous and current CT image pairs. The shift vectors are calculated by using nearest neighbor matching of the vector fields in these VOIs. The search kernel on previous CT image is set up from the obtained shift vector. The previous CT voxel which resemble standard the current voxel is detected by voxel value and vector of the GGVF in the kernel. And, the previous CT image is transformed to the same coordinate of standard voxel. Finally, temporal subtraction image is made by subtraction of a warping image from a current one. To verify the proposal method, the result of application to 7 cases and the effectiveness are described. (author)

Detection of aneurysms in subarachnoidal hemorrhage - CT-angiography versus digital subtraction angiography

International Nuclear Information System (INIS)

Roehnert, W.; Haenig, V.; Hietschold, V.; Abolmaali, N.

1998-01-01

Purpose: The value of CT-angiography (CT-A) for the visualization of intracranial aneurysms was more closely defined by comparison with digital subtraction angiography (DSA). Methods: Over a period of 18 months a total of 106 patients in whom a subarachnoidal hemorrhage had been detected on native CT were examined in parallel by spiral CT and DSA. CT-angiography was performed under standardized parameters and included processing with 3D surface reconstructions. Results: In 64 patients (60.4%) at total of 72 aneurysms were detected. In four cases (6.2%) there were two and in two cases (3.1%) even three aneurysms. The findings of DSA and CTA agreed in 98 cases (92.5%). In four patients (3.8%) a false negative results was obtained in CTA and the initial DSA. Conclusions: Digital subtraction angiography must still be considered as the gold standard in the diagnosis of cerebral aneurysms. On account of its excellent spatial delineation of aneurysms and possibilities for exact measurements, CT-angiography represents a valuable, supplementary method - in some cases also an alternative method - to digital subtraction angiography. (orig.) [de

Subtraction imaging of the ECG gated cardiac CT

Energy Technology Data Exchange (ETDEWEB)

Tanegashima, K.; Fukui, M.; Hyodo, H.

1987-05-01

The subtracting manipulation of contrast-enhanced gated cardiac CT (GCCT) images was experimentally studied with TCT 60A - 30 type (Toshiba) for clinical use, thereby reducing the amount of contrast medium (CM). Initially the optimum relationship between the concentration of CM and its injected velocity was determined using the model of resected canine hearts and in actual dogs. The emphasized good-subtracted images were obtained when the difference of CT values was approximately 40 H.U. between cardiac cavity and myocardium. Such condition was feasible in the use of 25 % Diatrizoic acid and its injected velocity of 0.02 ml/kg/sec. Finally the reduction of the amount of CM by 1/3 became possible in clinical settings. The method is applicable to multi-slice GCCT in various heart diseases.

Clinical application of subtraction CT imaging for evaluation of pulmonary vascular permeability

International Nuclear Information System (INIS)

Kato, Shiro; Asai, Toshihiko; Yatagai, Shigeo; Oonuma, Noboru; Ohno, Kunihiko; Nakamoto, Takaaki; Iizuka, Masahiko

1991-01-01

In this clinical study, one normal subject, one patient with primary interstitial pneumonia, one patient with segmental pneumonia due to Staphylococcus aureus, one patient with post-operative esophageal carcinoma, and two patients with mitral stenosis were studied. Dynamic CT scan images under continuous injection of low osmotic contrast medium were analyzed in series, in an attempt to evaluate vascular permeability quantitatively. The following results were obtained. Subtraction CT scan image 10 minutes after the start of contrast medium injection in two patients with pneumonia, showed a reduction of pulmonary vascular permeability following therapy. Subtraction CT scan image of the patient with post-operative esophageal carcinoma treated with 25 Gy radiation showed a discrepancy between pulmonary vascular permeability and other findings. In hemodynamically stable patients with mitral stenosis, subtraction CT images demonstrated that pulmonary vascular permeability was not affected by pulmonary congestion, irrespective of its severity. (author)

Thallium-201 and technetium-99m pertechnetate subtraction scintigraphy in patients with hyperparathyroidism

International Nuclear Information System (INIS)

Kuwashima, Shigeko; Koizumi, Mitsuru; Goto, Masafumi; Nomura, Toshiharu; Fujioka, Mutsuhisa; Watari, Tsutomu

1992-01-01

A reliable technique for detecting and localizing abnormal parathyroid tissue has been a persistent problem. We evaluated thallium-technetium (Tl/Tc) subtraction scintigraphy in 16 patients with clinical biochemical evidence of hyperparathyroidism prior to other diagnostic methods and surgery. Seven patients had surgery and were confirmed to have parathyroid adenoma or hyperplasia. The other methods included ultrasonography (US) in 6 patients, computed tomography (CT) in 10 patients, magnetic resonance imaging (MRI) in 8 patients, and bone scintigraphy in 7 patients. In patients who had several imaging modalities, the detection rate was significantly better for Tl/Tc subtraction scan than for US, CT or MRI. Bote scintigraphy, though not so sensitive as Tl/Tc subtraction studies, was an important tool for evaluating metabolic bone disorder including hyperparathyroidism and renal osteodystrophy. Thus, Tl/Tc subtraction scan is more useful for diagnosis when hyperparathyroidism is suspected if both Tl/Tc subtraction scan and bone scan are performed. The detectability depended on the mass size, and detection of abnormal glands was greater for adenoma than for hyperplasia. The results suggest that Tl/Tc subtraction scan is a simple, non-invasive and useful tool for locating parathyroid abnormality even when compared with MRI. (author)

High resolution CT of temporal bone trauma

International Nuclear Information System (INIS)

Youn, Eun Kyung

1986-01-01

Radiographic studies of the temporal bone following head trauma are indicated when there is cerebrospinal fluid otorrhea or rhinorrhoea, hearing loss, or facial nerve paralysis. Plain radiography displays only 17-30% of temporal bone fractures and pluridirectional tomography is both difficult to perform, particularly in the acutely ill patient, and less satisfactory for the demonstration of fine fractures. Consequently, high resolution CT is the imaging method of choice for the investigation of suspected temporal bone trauma and allows special resolution of fine bony detail comparable to that attainable by conventional tomography. Eight cases of temporal bone trauma examined at Korea General Hospital April 1985 through May 1986. The results were as follows: Seven patients (87%) suffered longitudinal fractures. In 6 patients who had purely conductive hearing loss, CT revealed various ossicular chain abnormality. In one patient who had neuro sensory hearing loss, CT demonstrated intract ossicular with a fracture nearing lateral wall of the lateral semicircular canal. In one patient who had mixed hearing loss, CT showed complex fracture.

Combined SPECT/CT improves detection of initial bone invasion and determination of resection margins in squamous cell carcinoma of the head and neck compared to conventional imaging modalities

Energy Technology Data Exchange (ETDEWEB)

Kolk, A. [Technische Universitaet Muenchen, Klinikum rechts der Isar, Department of Oral and Maxillofacial Surgery, Munich (Germany); Klinikum rechts der Isar, Technische Universitaet Muenchen, Klinik und Poliklinik fuer Mund-Kiefer und Gesichtschirurgie, Muenchen (Germany); Schuster, T. [Technische Universitaet Muenchen, Klinikum rechts der Isar, Institute of Medical Statistics and Epidemiology, Munich (Germany); Chlebowski, A.; Kesting, M.; Bissinger, O.; Weitz, J. [Technische Universitaet Muenchen, Klinikum rechts der Isar, Department of Oral and Maxillofacial Surgery, Munich (Germany); Lange, P. [Technische Universitaet Muenchen, Klinikum rechts der Isar, Department of Diagnostic Radiology, Munich (Germany); Scheidhauer, K.; Schwaiger, M.; Dinges, J. [Technische Universitaet Muenchen, Klinikum rechts der Isar, Department of Nuclear Medicine, Munich (Germany)

2014-07-15

Knowledge of the presence and extent of bone infiltration is crucial for planning the resection of potential bone-infiltrating squamous cell carcinomas of the head and neck (HNSCC). Routinely, plain-film radiography, multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) are used for preoperative staging, but they show relatively high rates of false-positive and false-negative findings. Scintigraphy with {sup 99m}Tc-bisphosphonate has the ability to show increased metabolic bone activity. If combined with anatomical imaging (e.g. (SPECT)/CT), it facilitates the precise localization of malignant bone lesions. The aim of this study was to analyse the indications and advantages of SPECT/CT compared with standard imaging modalities and histology with regard to specificity and sensitivity A longitudinally evaluated group of 30 patients with biopsy-proven HNSCC adjacent to the mandible underwent {sup 99m}Tc-bisphosphonate SPECT/CT, MRI, MSCT and conventional radiography before partial or rim resection of the mandible was performed. Bone infiltration was first evaluated with plain films, MSCT and MRI. In a second reading, SPECT/CT data were taken into account. The results (region and certainty of bone invasion) were evaluated among the different imaging modalities and finally compared with histological specimens from surgical resection as the standard of reference. For a better evaluation of the hybrid property of SPECT/CT, a retrospectively evaluated group of 20 additional patients with tumour locations similar to those of the longitudinally examined SPECT/CT group underwent SPECT, MSCT and MRI. To assess the influence of dental foci on the specificity of the imaging modalities, all patients were separated into two subgroups depending on the presence or absence of teeth in the area of potential tumour-bone contact. Histologically proven bone infiltration was found in 17 patients (57 %) when analysed by conventional imaging modalities. SPECT/CT data

Combined SPECT/CT improves detection of initial bone invasion and determination of resection margins in squamous cell carcinoma of the head and neck compared to conventional imaging modalities

International Nuclear Information System (INIS)

Kolk, A.; Schuster, T.; Chlebowski, A.; Kesting, M.; Bissinger, O.; Weitz, J.; Lange, P.; Scheidhauer, K.; Schwaiger, M.; Dinges, J.

2014-01-01

Knowledge of the presence and extent of bone infiltration is crucial for planning the resection of potential bone-infiltrating squamous cell carcinomas of the head and neck (HNSCC). Routinely, plain-film radiography, multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) are used for preoperative staging, but they show relatively high rates of false-positive and false-negative findings. Scintigraphy with 99m Tc-bisphosphonate has the ability to show increased metabolic bone activity. If combined with anatomical imaging (e.g. (SPECT)/CT), it facilitates the precise localization of malignant bone lesions. The aim of this study was to analyse the indications and advantages of SPECT/CT compared with standard imaging modalities and histology with regard to specificity and sensitivity A longitudinally evaluated group of 30 patients with biopsy-proven HNSCC adjacent to the mandible underwent 99m Tc-bisphosphonate SPECT/CT, MRI, MSCT and conventional radiography before partial or rim resection of the mandible was performed. Bone infiltration was first evaluated with plain films, MSCT and MRI. In a second reading, SPECT/CT data were taken into account. The results (region and certainty of bone invasion) were evaluated among the different imaging modalities and finally compared with histological specimens from surgical resection as the standard of reference. For a better evaluation of the hybrid property of SPECT/CT, a retrospectively evaluated group of 20 additional patients with tumour locations similar to those of the longitudinally examined SPECT/CT group underwent SPECT, MSCT and MRI. To assess the influence of dental foci on the specificity of the imaging modalities, all patients were separated into two subgroups depending on the presence or absence of teeth in the area of potential tumour-bone contact. Histologically proven bone infiltration was found in 17 patients (57 %) when analysed by conventional imaging modalities. SPECT/CT data revealed

Clinical utility of Gd-DTPA subtraction MR imaging for spinal bone metastasis

International Nuclear Information System (INIS)

Ando, Keiichi; Murakami, Masao; Kuroda, Yasumasa

1993-01-01

Based on reports that Gd-DTPA contributes to the detection of tumors, we used it in 31 cases (97 lesions) of spinal bone metastases. The result was that Gd-DTPA increased the intensity of tumors and the surrounding bone marrow to almost the same level in 53%. To show the metastases clearly, an existing subtraction command system was utilized. The technique included the pixel-by-pixel method, to obtain a Gd-DTPA T1-weighted image (T1WI) subtracted by the original T1WI. The detectability of the subtraction image was improved up to 96%, but was less than the original T1WI (99%). Because of the different imaging rationale between two methods, a means to assess the quality of diagnosis must be proposed. To check the normal background, the same kind of postprocessing was performed in 21 patients without malignancy. Gd-DTPA prefusion was highest in the paravertebral veins, moderate in muscles and epidural fat, and lowest in the spinal cord, intervertebral disk and bone cortex. Gd-DTPA enhanced subtraction MR imaging provides a new diagnostic tool to detect and to assess bone metastasis. (author)

CT-scanning of ancient Greenlandic Inuit temporal bones

International Nuclear Information System (INIS)

Homoe, P.; Videbaek, H.

1992-01-01

Additional morphological evidence of former infectious middle ear disease (IMED) was found by CT-scanning in 5 of 6 Greenlandic Inuit crania strongly suspected for former IMED due to earlier examination revealing either bilateral hypocellularity or asymmetry of the pneumatized area of the temporal bones. The CT-scans showed sclerosing and obliteration of the air cells and even destruction of the cellular septae, and a high degree of irregularity of the cells. Sclerosing of the surrounding bone tissue was also found. The findings in one cranium were dubious and could both be regarded as a congenital malformation or an infection in infanthood. CT-scan confirms and even adds to the results of conventional X-ray of temporal bones making hypotheses of paleopathology more reliable. The findings also support the environmental theory of pneumatization of the air cell system in the temporal bones. (13 refs., 10 figs.)

CT-scanning of ancient Greenlandic Inuit temporal bones

Energy Technology Data Exchange (ETDEWEB)

Homoe, P [Copenhagen Univ. (Denmark). Lab. of Biological Anthropology and Dept. of Otolaryngology, Head and Neck Surgery; Lynnerup, N [Copenhagen Univ., Lab. of Biological Anthropology and Univ. Inst. of Ferensic Medicine, Copenhagen (Denmark); Videbaek, H [Hvidovre Univ. Hospital, Copenhagen (Denmark). Dept. of Radiology

1992-01-01

Additional morphological evidence of former infectious middle ear disease (IMED) was found by CT-scanning in 5 of 6 Greenlandic Inuit crania strongly suspected for former IMED due to earlier examination revealing either bilateral hypocellularity or asymmetry of the pneumatized area of the temporal bones. The CT-scans showed sclerosing and obliteration of the air cells and even destruction of the cellular septae, and a high degree of irregularity of the cells. Sclerosing of the surrounding bone tissue was also found. The findings in one cranium were dubious and could both be regarded as a congenital malformation or an infection in infanthood. CT-scan confirms and even adds to the results of conventional X-ray of temporal bones making hypotheses of paleopathology more reliable. The findings also support the environmental theory of pneumatization of the air cell system in the temporal bones. (13 refs., 10 figs.).

Conventional diagnostic imaging of the temporal bone. A historical review

International Nuclear Information System (INIS)

Canigiani, G.

1997-01-01

The Viennese Medical School played an important role in the development of radiological examinations and signs of the temporal bone with conventional X-rays. Famous pioneers include E.G. Mayer (1893-1969) and L. Psenner (1910-1986). Nowadays conventional X-rays and tomography have lost their important role in diagnostic radiology of the temporal bone, but the basic principles established in those early years of radiology are still used now. This statement is correct not only for conventional X-rays, but particularly for 'poly'-tomography in comparison with CT. (orig.) [de

Improvement of temporal and dynamic subtraction images on abdominal CT using 3D global image matching and nonlinear image warping techniques

International Nuclear Information System (INIS)

Okumura, E; Sanada, S; Suzuki, M; Takemura, A; Matsui, O

2007-01-01

Accurate registration of the corresponding non-enhanced and arterial-phase CT images is necessary to create temporal and dynamic subtraction images for the enhancement of subtle abnormalities. However, respiratory movement causes misregistration at the periphery of the liver. To reduce these misregistration errors, we developed a temporal and dynamic subtraction technique to enhance small HCC by 3D global matching and nonlinear image warping techniques. The study population consisted of 21 patients with HCC. Using the 3D global matching and nonlinear image warping technique, we registered current and previous arterial-phase CT images or current non-enhanced and arterial-phase CT images obtained in the same position. The temporal subtraction image was obtained by subtracting the previous arterial-phase CT image from the warped current arterial-phase CT image. The dynamic subtraction image was obtained by the subtraction of the current non-enhanced CT image from the warped current arterial-phase CT image. The percentage of fair or superior temporal subtraction images increased from 52.4% to 95.2% using the new technique, while on the dynamic subtraction images, the percentage increased from 66.6% to 95.2%. The new subtraction technique may facilitate the diagnosis of subtle HCC based on the superior ability of these subtraction images to show nodular and/or ring enhancement

Three-dimensional versus conventional CT in the evaluation of facial trauma

International Nuclear Information System (INIS)

Mayer, J.S.; Yeakley, J.W.; Kulkarni, M.V.; Wainwright, D.J.; Lee, K.F.; Harris, J.H. Jr.

1987-01-01

An accurate knowledge of the three-dimensional pattern of facial fractures is surgically important. This exhibit shows how this may be difficult if not impossible to obtain using axial and reconstructed CT images and how 3D CT is superior in this regard. 3D CT displays the course of anterior and lateral facial fractures and the spatial orientation of bone fragments that can be missed when using other CT techniques. 3D CT and facial CT images can be generated from a single CT examination and are complementary. Together they display posttraumatic facial anatomy better than conventional planar CT images

Bone demarcation of the temporomandibular joint. Validity of clinical assessment of bone thickness by means of CT

International Nuclear Information System (INIS)

Ahlqvist, J.B.; Isberg, A.M.

1998-01-01

Purpose: To study the CT depiction of bone demarcations in the temporomandibular joint, using conventional window level and window width; and to evaluate observer performance in estimating bone thickness in these images. Material and Methods: Seven joint specimens were imaged by CT and then cryosectioned. The measurements of bone wall thickness in the images were compared to the true bone thickness at each cutting level. In addition, 4 experienced radiologists estimated the thickness of the bone walls in the images. Results: The relative difference between the CT reproduction and the true bone thickness was small for bone walls thicker than 2 mm. This difference increased with the decrease in bone thickness and the increase in the inclination of the bone wall from the perpendicular to the image plane. Bone walls thinner than 1 mm were reproduced as considerably thicker than their true thickness. This resulted in a clinical overestimation of bone thickness. Conclusion: Both the CT representation and the interpretation of bone demarcation in the temporomandibular joint may constitute a problem. Partial volume averaging effects can result in an overestimation of bone dimensions amounting to 200% for thin bones. The central white zone in images of thin bone walls obtained with the parameters described here could serve as an indicator that could help to reduce the risk of overestimating bone thickness. (orig.)

Removal of arterial wall calcifications in CT angiography by local subtraction

International Nuclear Information System (INIS)

Straten, Marcel van; Venema, Henk W.; Streekstra, Geert J.; Reekers, Jim A.; Heeten, Gerard J. den; Grimbergen, Cornelis A.

2003-01-01

CT Angiography (CTA) is an established technique for the minimally invasive imaging of arteries. The technique of maximum intensity projection (MIP) is often used to get a comprehensive overview of the vascular anatomy. On a MIP, however, arterial wall calcifications may hinder the visualization of the arterial lumen. These calcifications are in direct contact with the contrast-enhanced blood, which makes removal difficult. We present a local subtraction method for the automatic removal of these calcifications. In our approach a second CT scan has to be made, prior to contrast injection. The calcifications in both scans are registered prior to subtraction to compensate for displacements in between the two scans. Local subtraction results are compared with results obtained by thresholding. The method was tested in a phantom and with data from four patients. The phantom represented an artery with different types of stenosis. Data were used from patients for which CTA of the renal arteries was performed. For two patients the electrocardiogram (ECG) was recorded during the CTA examination, making retrospective cardiac gated reconstructions possible. Both the phantom and the patient study showed that the local subtraction method is capable of removing calcifications and visualizing the residual lumen. In the patient study it appeared that some artifacts remained for higher pitch values. We conclude that the local subtraction method is less subjective and more accurate than thresholding. Best results are obtained by use of a small pitch, at the expense of the volume covered during a single breath hold

[Development of a digital chest phantom for studies on energy subtraction techniques].

Science.gov (United States)

Hayashi, Norio; Taniguchi, Anna; Noto, Kimiya; Shimosegawa, Masayuki; Ogura, Toshihiro; Doi, Kunio

2014-03-01

Digital chest phantoms continue to play a significant role in optimizing imaging parameters for chest X-ray examinations. The purpose of this study was to develop a digital chest phantom for studies on energy subtraction techniques under ideal conditions without image noise. Computed tomography (CT) images from the LIDC (Lung Image Database Consortium) were employed to develop a digital chest phantom. The method consisted of the following four steps: 1) segmentation of the lung and bone regions on CT images; 2) creation of simulated nodules; 3) transformation to attenuation coefficient maps from the segmented images; and 4) projection from attenuation coefficient maps. To evaluate the usefulness of digital chest phantoms, we determined the contrast of the simulated nodules in projection images of the digital chest phantom using high and low X-ray energies, soft tissue images obtained by energy subtraction, and "gold standard" images of the soft tissues. Using our method, the lung and bone regions were segmented on the original CT images. The contrast of simulated nodules in soft tissue images obtained by energy subtraction closely matched that obtained using the gold standard images. We thus conclude that it is possible to carry out simulation studies based on energy subtraction techniques using the created digital chest phantoms. Our method is potentially useful for performing simulation studies for optimizing the imaging parameters in chest X-ray examinations.

Virtual non-contrast computer tomography (CT) with spectral CT as an alternative to conventional unenhanced CT in the assessment of gastric cancer.

Science.gov (United States)

Tian, Shi-Feng; Liu, Ai-Lian; Wang, He-Qing; Liu, Jing-Hong; Sun, Mei-Yu; Liu, Yi-Jun

2015-01-01

The purpose of this study was to evaluate computed tomography (CT) virtual non-contrast (VNC) spectral imaging for gastric carcinoma. Fifty-two patients with histologically proven gastric carcinomas underwent gemstone spectral imaging (GSI) including non-contrast and contrast-enhanced hepatic arterial, portal venous, and equilibrium phase acquisitions prior to surgery. VNC arterial phase (VNCa), VNC venous phase (VNCv), and VNC equilibrium phase (VNCe) images were obtained by subtracting iodine from iodine/water images. Images were analyzed with respect to image quality, gastric carcinoma-intragastric water contrast-to-noise ratio (CNR), gastric carcinoma-perigastric fat CNR, serosal invasion, and enlarged lymph nodes around the lesions. Carcinoma-water CNR values were significantly higher in VNCa, VNCv, and VNCe images than in normal CT images (2.72, 2.60, 2.61, respectively, vs 2.35, p≤0.008). Carcinoma- perigastric fat CNR values were significantly lower in VNCa, VNCv, and VNCe images than in normal CT images (7.63, 7.49, 7.32, respectively, vs 8.48, pVNC arterial phase images may be a surrogate for conventional non-contrast CT images in gastric carcinoma evaluation.

Bone SPECT/CT in the postoperative spine: a focus on spinal fusion

Energy Technology Data Exchange (ETDEWEB)

Al-Riyami, Khulood; Bomanji, Jamshed [University College London Hospitals, Institute of Nuclear Medicine, London (United Kingdom); Gnanasegaran, Gopinath [Royal Free Hospital, Department of Nuclear Medicine, London (United Kingdom); Wyngaert, Tim van den [Antwerp University Hospital, Department of Nuclear Medicine, Edegem (Belgium); University of Antwerp, Faculty of Medicine and Health Sciences, Wilrijk (Belgium)

2017-11-15

Low back pain is a global problem affecting one in 10 people. The management of low back pain varies from conservative to more invasive methods with a spectacular increase in the number of patients undergoing spinal fusion surgery during the last decade. Conventional radiological and radionuclide studies are often used in the assessment of persistent or recurring pain after spinal surgery with several advantages and limitations related to each technique. This article reviews the key contribution of integrated bone SPECT/CT in evaluating patients with persistent or recurring pain after spinal surgery, focusing on spinal fusion. Current literature supports the use of bone SPECT/CT as an adjunct imaging modality and problem-solving tool in evaluating patients with suspicion of pseudarthrosis, adjacent segment degeneration, and hardware failure. The role of bone SPECT/CT in post-operative orthopaedic scenarios is evolving, and this review highlights the need for further research on the role of bone SPECT/CT in these patients. (orig.)

Site specific measurements of bone formation using [18F] sodium fluoride PET/CT.

Science.gov (United States)

Blake, Glen M; Puri, Tanuj; Siddique, Musib; Frost, Michelle L; Moore, Amelia E B; Fogelman, Ignac

2018-02-01

Dynamic positron emission tomography (PET) imaging with fluorine-18 labelled sodium fluoride ([ 18 F]NaF) allows the quantitative assessment of regional bone formation by measuring the plasma clearance of fluoride to bone at any site in the skeleton. Today, hybrid PET and computed tomography (CT) dual-modality systems (PET/CT) are widely available, and [ 18 F]NaF PET/CT offers a convenient non-invasive method of studying bone formation at the important osteoporotic fracture sites at the hip and spine, as well as sites of pure cortical or trabecular bone. The technique complements conventional measurements of bone turnover using biochemical markers or bone biopsy as a tool to investigate new therapies for osteoporosis, and has a potential role as an early biomarker of treatment efficacy in clinical trials. This article reviews methods of acquiring and analyzing dynamic [ 18 F]NaF PET/CT scan data, and outlines a simplified approach combining venous blood sampling with a series of short (3- to 5-minute) static PET/CT scans acquired at different bed positions to estimate [ 18 F]NaF plasma clearance at multiple sites in the skeleton with just a single injection of tracer.

Quantitative Assessment of Degenerative Cartilage and Subchondral Bony Lesions in a Preserved Cadaveric Knee: Propagation-Based Phase-Contrast CT Versus Conventional MRI and CT.

Science.gov (United States)

Geith, Tobias; Brun, Emmanuel; Mittone, Alberto; Gasilov, Sergei; Weber, Loriane; Adam-Neumair, Silvia; Bravin, Alberto; Reiser, Maximilian; Coan, Paola; Horng, Annie

2018-04-09

The aim of this study was to quantitatively assess hyaline cartilage and subchondral bone conditions in a fully preserved cadaveric human knee joint using high-resolution x-ray propagation-based phase-contrast imaging (PBI) CT and to compare the performance of the new technique with conventional CT and MRI. A cadaveric human knee was examined using an x-ray beam of 60 keV, a detector with a 90-mm 2 FOV, and a pixel size of 46 × 46 μm 2 . PBI CT images were reconstructed with both the filtered back projection algorithm and the equally sloped tomography method. Conventional 3-T MRI and CT were also performed. Measurements of cartilage thickness, cartilage lesions, International Cartilage Repair Society scoring, and detection of subchondral bone changes were evaluated. Visual inspection of the specimen akin to arthroscopy was conducted and served as a standard of reference for lesion detection. Loss of cartilage height was visible on PBI CT and MRI. Quantification of cartilage thickness showed a strong correlation between the two modalities. Cartilage lesions appeared darker than the adjacent cartilage on PBI CT. PBI CT showed similar agreement to MRI for depicting cartilage substance defects or lesions compared with the visual inspection. The assessment of subchondral bone cysts showed moderate to strong agreement between PBI CT and CT. In contrast to the standard clinical methods of MRI and CT, PBI CT is able to simultaneously depict cartilage and bony changes at high resolution. Though still an experimental technique, PBI CT is a promising high-resolution imaging method to evaluate comprehensive changes of osteoarthritic disease in a clinical setting.

CT diagnosis of occipital bone pacchionian depression

International Nuclear Information System (INIS)

Zhu Jianguo; Xu Xiaolin

2004-01-01

Objective: To improve the recognition of the CT findings of occipital bone pacchionian depression, in order to avoid misdiagnosis. Methods: occipital bone pacchionian depression underwent CT with plain scan and intravenous contrast enhancement in 11 cases, and then the CT findings were analyzed. Results: Occipital bone pacchionian depression situated beside the torcular herophilia in 11 cases. The depression or bone defect were found at occipital bone inner plate, they can reach diploe or outer plate and had no enhancement after contrast injection. Conclusions: CT scans play an important role in diagnosis and differential diagnosis of occipital bone pacchionian depression

CT paging arteriography with a multidetector-row CT. Advantages in splanchnic arterial imaging

Energy Technology Data Exchange (ETDEWEB)

Kobayashi, Seiji [Keio Univ., Tokyo (Japan). School of Medicine

1999-11-01

The purpose of this study is to assess the utility of CT paging arteriography with a multidetector-row CT as a replacement for conventional angiography in the evaluation of splanchnic arterial anomalies. Sixty-three patients underwent CT paging arteriography with a multidetector-row CT. In the 56 patients with conventional angiographic correlation, there was only one minor disagreement with CT paging arteriography. In the 7 patients who underwent IVDSA (intra venous digital subtraction angiography), CT paging arteriography defined four hepatic arterial anomalies which could not be depicted by IVDSA. In conclusion, CT paging arteriography provides noninvasive means to identify splanchnic arterial anomalies. (author)

The effect of the cranial bone CT numbers on the brain CT numbers

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Fukuda, Hitoshi; Kobayashi, Shotai; Koide, Hiromi; Yamaguchi, Shuhei; Okada, Kazunori; Shimote, Koichi; Tsunematsu, Tokugoro (Shimane Medical Univ., Izumo (Japan))

1989-06-01

The effects of the cranial size and the computed tomography (CT) numbers of the cranial bone on that of the brain were studied in 70 subjects, aged from 30 to 94 years. The subjects had no histories of cerebrovascular accidents and showed no abnormalities in the central nervous system upon physical examinations and a CT scan. We measured the average attenuation values (CT numbers) of each elliptical region (165 pixels, 0.39 cm{sup 2}) at the bilateral thalamus and at twelve areas of the deep white matter. Multiple regression analysis was used to assess the effects of age, cranial size, and cranial bone CT numbers on the brain CT numbers. The effect of the cranial bone CT numbers on the brain CT numbers was statistically significant. The brain CT numbers increased with the increase in the cranial bone CT numbers. There was, however, no significant correlation between brain CT numbers and cranial size. In measuring the brain CT numbers, it is desirable that consideration be given to the cranial bone CT numbers. (author).

Multi-section CT angiography compared with digital subtraction angiography in diagnosing major arterial hemorrhage in inflammatory pancreatic disease

International Nuclear Information System (INIS)

Hyare, Harpreet; Desigan, Sharmini; Nicholl, Helen; Guiney, Michael J.; Brookes, Jocelyn A.; Lees, William R.

2006-01-01

Purpose: Major arterial hemorrhage is an uncommon but serious complication of pancreatitis with high morbidity and mortality. Digital subtraction angiography (DSA) has long been the gold standard for the detection of a visceral artery pseudoaneurysm or for the site of active bleeding in patients with pancreatitis. Multi-section CT angiography is a minimally invasive technique which can provide high-resolution and high-contrast images of the arterial lumen and wall, with a much lower risk of complication and morbidity compared to DSA. The aim of this study was to determine the accuracy of multi-section CT angiography for the diagnosis of arterial complications of inflammatory pancreatitic disease. Materials and methods: A retrospective analysis of all patients undergoing visceral angiography for major bleeding as a complication of pancreatitis between 1998 and 2004 was performed. Twenty-nine studies in 25 patients (20 males, 5 females) with a mean age of 50.9 years (range 11-67 years) were identified where multi-section CT angiography was performed in the 24 h preceding the digital subtraction angiogram. Results: Digital subtraction angiography detected a pseudoaneurysm or contrast extravasation in 19 studies and no bleeding was demonstrated in 9 studies. CT angiography correctly identified the site and type of bleeding in 18 of the 19 positive studies. CT angiography detected extravasation of contrast in one study that was not demonstrated on digital subtraction angiography. The sensitivity and specificity for multi-section CT angiography for the detection of major arterial bleeding on a background of pancreatitis were 0.947 and 0.900, respectively. Conclusion: Multi-section CT angiography is a sensitive and accurate technique for the detection of major arterial hemorrhage in inflammatory pancreatic disease and should be considered as the first investigation in the management of these patients

Evaluation of the utility of temporal subtraction images in successive whole-body bone scans: a prospective clinical study

International Nuclear Information System (INIS)

Shiraishi, J.; Appelbaum, D.; Pu, Y.; Engelmann, R.; Li Qiang; Doi, K.

2007-01-01

We have begun a prospective clinical study for evaluating the clinical utility of temporal subtraction images in successive whole-body bone scans. The computerized temporal subtraction technique has been developed in order to highlight interval changes of abnormal lesions due to skeletal metastases, primary bone tumors, osteomyelitis, and fractures. In our initial preliminary results of the prospective study which was started on November 22, 2006 in our hospital, radiologists reported some interval changes which were not recognized in the initial standard readings, but were obvious when temporal subtraction images were viewed. The usefulness of the temporal subtraction images will be investigated in terms of its clinical utility by the prospective clinical study. (orig.)

X-ray CT high-density artefact suppression in cryosurgery

International Nuclear Information System (INIS)

Wei Jikun; Sandison, George A; Chen Laigao; Liang Yun; Xu, Lisa X

2002-01-01

Advantages of x-ray CT for imaging guidance of cryosurgery include 3D visualization of frozen and unfrozen tissue and calibration of temperature in the tissue water-ice interface (0-10 deg. C) to Hounsfield units. However, use of x-ray CT images and their thermal calibration can be compromised by the cryoprobes generating high-density streak artefacts. A new subtraction technique for artefact suppression is proposed and tested in prostate cryosurgery simulations. By subtracting the measured CT x-ray projection profile without cryoprobes from the profile with cryoprobes plus iceballs, one obtains the combined profile of the cryoprobes and a low value background. Polynomial interpolation to obtain the background profile allows its addition to the original profile without probes. The result may then be fed to a conventional filtered back-projection routine to reconstruct the probe-free image. Finally the cryoprobe pixels in the originally constructed image with probes and iceballs are added back to the probe-free image to get the final artefact-suppressed image. The major advantage of this subtraction technique is that it can successfully suppress the high-density artefacts in bone-abundant body regions such as the pelvis. X-ray CT images of cryoprobe arrays in a homogeneous gelatin phantom and the pelvic region of an anthropomorphic Rando phantom containing a human skeleton were generated. After suppression, cryoprobe metal artefact streaks are reduced and visualization of the positions and dimensions of the cryoprobes are well preserved. (note)

PET/CT-guided biopsies of metabolically active bone lesions: applications and clinical impact

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Klaeser, Bernd; Wartenberg, Jan; Weitzel, Thilo; Krause, Thomas [Bern University Hospital and University of Bern, Department of Nuclear Medicine, Inselspital, Bern (Switzerland); Wiskirchen, Jakub [Bern University Hospital and University of Bern, Department of Nuclear Medicine, Inselspital, Bern (Switzerland); University Hospital Tuebingen, Department of Radiology, Neuroradiology, and Nuclear Medicine, Tuebingen (Germany); Schmid, Ralph A. [Bern University Hospital and University of Bern, Department of Thoracic Surgery, Inselspital, Bern (Switzerland); Mueller, Michel D. [Bern University Hospital and University of Bern, Department of Obstetrics and Gynaecology, Inselspital, Bern (Switzerland)

2010-11-15

In a minority of cases a definite diagnosis and stage grouping in cancer patients is not possible based on the imaging information of PET/CT. We report our experience with percutaneous PET/CT-guided bone biopsies to histologically verify the aetiology of hypermetabolic bone lesions. We retrospectively reviewed the data of 20 consecutive patients who underwent multimodal image-guided bone biopsies using a dedicated PET/CT system in a step-by-step technique. Technical and clinical success rates of PET/CT-guided biopsies were evaluated. Questionnaires were sent to the referring physicians to assess the impact of biopsies on patient management and to check the clinical need for PET/CT-guided biopsies. Clinical indications for biopsy were to histologically verify the aetiology of metabolically active bone lesions without a morphological correlate confirming the suspicion of metastases in 15 patients, to determine the origin of suspected metastases in 3 patients and to evaluate the appropriateness of targeted therapy options in 2 patients. Biopsies were technically successful in all patients. In 19 of 20 patients a definite histological diagnosis was possible. No complications or adverse effects occurred. The result of PET/CT-guided bone biopsies determined a change of the planned treatment in overall 56% of patients, with intramodality changes, e.g. chemotherapy with palliative instead of curative intent, and intermodality changes, e.g. systemic therapy instead of surgery, in 22 and 50%, respectively. PET/CT-guided bone biopsies are a promising alternative to conventional techniques to make metabolically active bone lesions - especially without a distinctive morphological correlate - accessible for histological verification. PET/CT-guided biopsies had a major clinical impact in patients who otherwise cannot be reliably stage grouped at the time of treatment decisions. (orig.)

Detection of pulmonary nodules on lung X-ray images. Studies on multi-resolutional filter and energy subtraction images

International Nuclear Information System (INIS)

Sawada, Akira; Sato, Yoshinobu; Kido, Shoji; Tamura, Shinichi

1999-01-01

The purpose of this work is to prove the effectiveness of an energy subtraction image for the detection of pulmonary nodules and the effectiveness of multi-resolutional filter on an energy subtraction image to detect pulmonary nodules. Also we study influential factors to the accuracy of detection of pulmonary nodules from viewpoints of types of images, types of digital filters and types of evaluation methods. As one type of images, we select an energy subtraction image, which removes bones such as ribs from the conventional X-ray image by utilizing the difference of X-ray absorption ratios at different energy between bones and soft tissue. Ribs and vessels are major causes of CAD errors in detection of pulmonary nodules and many researches have tried to solve this problem. So we select conventional X-ray images and energy subtraction X-ray images as types of images, and at the same time select ∇ 2 G (Laplacian of Guassian) filter, Min-DD (Minimum Directional Difference) filter and our multi-resolutional filter as types of digital filters. Also we select two evaluation methods and prove the effectiveness of an energy subtraction image, the effectiveness of Min-DD filter on a conventional X-ray image and the effectiveness of multi-resolutional filter on an energy subtraction image. (author)

Developmental venous anomalies: appearance on whole-brain CT digital subtraction angiography and CT perfusion

International Nuclear Information System (INIS)

Hanson, Eric H.; Roach, Cayce J.; Ringdahl, Erik N.; Wynn, Brad L.; DeChancie, Sean M.; Mann, Nathan D.; Diamond, Alan S.; Orrison, William W.

2011-01-01

Developmental venous anomalies (DVA) consist of dilated intramedullary veins that converge into a large collecting vein. The appearance of these anomalies was evaluated on whole-brain computed tomography (CT) digital subtraction angiography (DSA) and CT perfusion (CTP) studies. CT data sets of ten anonymized patients were retrospectively analyzed. Five patients had evidence of DVA and five age- and sex-matched controls were without known neurovascular abnormalities. CT angiograms, CT arterial-venous views, 4-D CT DSA and CTP maps were acquired on a dynamic volume imaging protocol on a 320-detector row CT scanner. Whole-brain CTP parameters were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and delay. DSA was utilized to visualize DVA anatomy. Radiation dose was recorded from the scanner console. Increased CTP values were present in the DVA relative to the unaffected contralateral hemisphere of 48%, 32%, and 26%; and for the control group with matched hemispheric comparisons of 2%, -10%, and 9% for CBF, CBV, and MTT, respectively. Average effective radiation dose was 4.4 mSv. Whole-brain DSA and CTP imaging can demonstrate a characteristic appearance of altered DVA hemodynamic parameters and capture the anomalies in superior cortices of the cerebrum and the cerebellum. Future research may identify the rare subsets of patients at increased risk of adverse outcomes secondary to the altered hemodynamics to facilitate tailored imaging surveillance and application of appropriate preventive therapeutic measures. (orig.)

Developmental venous anomalies: appearance on whole-brain CT digital subtraction angiography and CT perfusion

Energy Technology Data Exchange (ETDEWEB)

Hanson, Eric H. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); Amigenics, Inc, Las Vegas, NV (United States); Roach, Cayce J. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); University of Nevada Las Vegas, School of Life Sciences, Las Vegas, NV (United States); Ringdahl, Erik N. [University of Nevada Las Vegas, Department of Psychology, Las Vegas, NV (United States); Wynn, Brad L. [Family Medicine Spokane, Spokane, WA (United States); DeChancie, Sean M.; Mann, Nathan D. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); Diamond, Alan S. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); Orrison, William W. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); University of Nevada School of Medicine, Department of Medical Education, Reno, NV (United States)

2011-05-15

Developmental venous anomalies (DVA) consist of dilated intramedullary veins that converge into a large collecting vein. The appearance of these anomalies was evaluated on whole-brain computed tomography (CT) digital subtraction angiography (DSA) and CT perfusion (CTP) studies. CT data sets of ten anonymized patients were retrospectively analyzed. Five patients had evidence of DVA and five age- and sex-matched controls were without known neurovascular abnormalities. CT angiograms, CT arterial-venous views, 4-D CT DSA and CTP maps were acquired on a dynamic volume imaging protocol on a 320-detector row CT scanner. Whole-brain CTP parameters were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and delay. DSA was utilized to visualize DVA anatomy. Radiation dose was recorded from the scanner console. Increased CTP values were present in the DVA relative to the unaffected contralateral hemisphere of 48%, 32%, and 26%; and for the control group with matched hemispheric comparisons of 2%, -10%, and 9% for CBF, CBV, and MTT, respectively. Average effective radiation dose was 4.4 mSv. Whole-brain DSA and CTP imaging can demonstrate a characteristic appearance of altered DVA hemodynamic parameters and capture the anomalies in superior cortices of the cerebrum and the cerebellum. Future research may identify the rare subsets of patients at increased risk of adverse outcomes secondary to the altered hemodynamics to facilitate tailored imaging surveillance and application of appropriate preventive therapeutic measures. (orig.)

Staging of untreated nasopharyngeal carcinoma with PET/CT: comparison with conventional imaging work-up

International Nuclear Information System (INIS)

Ng, Shu-Hang; Chan, Sheng-Chieh; Yen, Tzu-Chen; Liu, Feng-Yuan; Chang, Joseph Tung-Chieh; Fan, Kang-Hsing; Liao, Chun-Ta; Ko, Sheung-Fat; Chin, Shu-Chyn; Hsu, Cheng-Lung

2009-01-01

We prospectively compared PET/CT and conventional imaging for initial staging of nasopharyngeal carcinoma (NPC). A total of 111 patients with histologically proven NPC were investigated with PET/CT and conventional imaging (head-and-neck MRI, chest X-ray, abdominal ultrasound, and bone scan) before treatment. The respective findings were reviewed independently and then compared with each other. With regard to T staging, PET/CT showed a discrepancy with head-and-neck MRI in 36 (32.4%) of the study subjects. With regard to N staging, PET/CT showed a discrepancy with head-and-neck MRI in 15 (13.5%) patients. Among the discordant cases, MRI was superior in demonstrating tumor involvement in the parapharyngeal space, skull base, intracranial area, sphenoid sinus, and retropharyngeal nodes while PET/CT was superior in demonstrating neck nodal metastasis. PET/CT disclosed 13 of 16 patients with distant malignancy compared with four patients disclosed by conventional imaging work-up. The false-positive rate of PET/CT was 18.8%. PET/CT correctly modified M staging in eight patients (7.2%) and disclosed a second primary lung malignancy in one patient (0.9%). In NPC patients, MRI appears to be superior to PET/CT for the assessment of locoregional invasion and retropharyngeal nodal metastasis. PET/CT is more accurate than MRI for determining cervical nodal metastasis and should be the better reference for the neck status. PET/CT has an acceptable diagnostic yield and a low false-positive rate for the detection of distant malignancy and can replace conventional work-up to this aim. PET/CT and head-and-neck MRI are suggested for the initial staging of NPC patients. (orig.)

Bone quality evaluation at dental implant site using multislice CT, micro-CT, and cone beam CT.

Science.gov (United States)

Parsa, Azin; Ibrahim, Norliza; Hassan, Bassam; van der Stelt, Paul; Wismeijer, Daniel

2015-01-01

The first purpose of this study was to analyze the correlation between bone volume fraction (BV/TV) and calibrated radiographic bone density Hounsfield units (HU) in human jaws, derived from micro-CT and multislice computed tomography (MSCT), respectively. The second aim was to assess the accuracy of cone beam computed tomography (CBCT) in evaluating trabecular bone density and microstructure using MSCT and micro-CT, respectively, as reference gold standards. Twenty partially edentulous human mandibular cadavers were scanned by three types of CT modalities: MSCT (Philips, Best, the Netherlands), CBCT (3D Accuitomo 170, J Morita, Kyoto, Japan), and micro-CT (SkyScan 1173, Kontich, Belgium). Image analysis was performed using Amira (v4.1, Visage Imaging Inc., Carlsbad, CA, USA), 3Diagnosis (v5.3.1, 3diemme, Cantu, Italy), Geomagic (studio(®) 2012, Morrisville, NC, USA), and CTAn (v1.11, SkyScan). MSCT, CBCT, and micro-CT scans of each mandible were matched to select the exact region of interest (ROI). MSCT HU, micro-CT BV/TV, and CBCT gray value and bone volume fraction of each ROI were derived. Statistical analysis was performed to assess the correlations between corresponding measurement parameters. Strong correlations were observed between CBCT and MSCT density (r = 0.89) and between CBCT and micro-CT BV/TV measurements (r = 0.82). Excellent correlation was observed between MSCT HU and micro-CT BV/TV (r = 0.91). However, significant differences were found between all comparisons pairs (P micro-CT BV/TV (P = 0.147). An excellent correlation exists between bone volume fraction and bone density as assessed on micro-CT and MSCT, respectively. This suggests that bone density measurements could be used to estimate bone microstructural parameters. A strong correlation also was found between CBCT gray values and BV/TV and their gold standards, suggesting the potential of this modality in bone quality assessment at implant site. © 2013 John Wiley & Sons A/S. Published by

320-Multidetector row whole-head dynamic subtracted CT angiography and whole-brain CT perfusion before and after carotid artery stenting: Technical note

International Nuclear Information System (INIS)

San Millan Ruiz, Diego; Murphy, Kieran; Gailloud, Philippe

2010-01-01

Introduction: Multidetector CT (MDCT) is increasingly used for the investigation of neurovascular disorders, but restricted z-axis coverage (3.2 cm for 64-MDCT) currently limits perfusion to a small portion of the brain close to the circle of Willis, and precludes dynamic angiographic appreciation of the entire brain circulation. We illustrate the clinical potential of recently developed 320-MDCT extending the z-axis coverage to 16 cm in a patient with symptomatic carotid artery stenosis. Methods: In a 74-year-old patient presenting with critical symptomatic stenosis of the left CCA, pre- and post-carotid artery stenting whole-head subtracted dynamic MDCT angiography and perfusion were obtained in addition to CT angiography of the supra-aortic trunks. Both whole-head subtracted MDCT angiography and perfusion demonstrated delayed left ICA circulation, which normalized after carotid stenting. Discussion: 320-MDCT offers unprecedented z-axis coverage allowing for whole-brain perfusion and subtracted dynamic angiography of the entire intracranial circulation. These innovations can consolidate the role of MDCT as a first intention imaging technique for cerebrovascular disorders, in particular for the acute management of stroke.

Spiral CT versus conventional CT in the preoperative assessment of metallic intraocular foreign bodies

International Nuclear Information System (INIS)

Prokesch, R.; Bankier, A.; Ba-Ssalamah, A.; Imhof, H.; Lakits, A.; Scholda, C.

1998-01-01

Purpose: To compare the effectiveness of spiral CT versus conventional CT in the preoperative assessment of metallic intraocular foreign bodies. Results: All foreign bodies were detected by each scanning modality on the axial and on the reconstructed planes. The quality of the axial images was similar for spiral and conventional CT. The spiral technique provided high-quality reconstructed images which allowed accurate localization of the foreign bodies in all cases. Reconstructions by conventional technique were inadequate for preoperative assessment. The examination time for the total orbital volume was 18 s for spiral CT and 52 s for conventional CT. Radiation dose delivered to the lens was 35 mGy for spiral CT and 56 mGy for conventional CT axial scanning. Conclusion: Spiral CT multiplanar offers several significant advantages for the preoperative assessment of metallic intraocular foreign bodies compared to the conventional CT technique in clinical practice, including short examination time, minimized motion artifacts, reduced radiation exposure, and accurate localization. (orig.) [de

Computed tomography lung iodine contrast mapping by image registration and subtraction

Science.gov (United States)

Goatman, Keith; Plakas, Costas; Schuijf, Joanne; Beveridge, Erin; Prokop, Mathias

2014-03-01

Pulmonary embolism (PE) is a relatively common and potentially life threatening disease, affecting around 600,000 people annually in the United States alone. Prompt treatment using anticoagulants is effective and saves lives, but unnecessary treatment risks life threatening haemorrhage. The specificity of any diagnostic test for PE is therefore as important as its sensitivity. Computed tomography (CT) angiography is routinely used to diagnose PE. However, there are concerns it may over-report the condition. Additional information about the severity of an occlusion can be obtained from an iodine contrast map that represents tissue perfusion. Such maps tend to be derived from dual-energy CT acquisitions. However, they may also be calculated by subtracting pre- and post-contrast CT scans. Indeed, there are technical advantages to such a subtraction approach, including better contrast-to-noise ratio for the same radiation dose, and bone suppression. However, subtraction relies on accurate image registration. This paper presents a framework for the automatic alignment of pre- and post-contrast lung volumes prior to subtraction. The registration accuracy is evaluated for seven subjects for whom pre- and post-contrast helical CT scans were acquired using a Toshiba Aquilion ONE scanner. One hundred corresponding points were annotated on the pre- and post-contrast scans, distributed throughout the lung volume. Surface-to-surface error distances were also calculated from lung segmentations. Prior to registration the mean Euclidean landmark alignment error was 2.57mm (range 1.43-4.34 mm), and following registration the mean error was 0.54mm (range 0.44-0.64 mm). The mean surface error distance was 1.89mm before registration and 0.47mm after registration. There was a commensurate reduction in visual artefacts following registration. In conclusion, a framework for pre- and post-contrast lung registration has been developed that is sufficiently accurate for lung subtraction

A comparison of methods for demonstrating artificial bone lesions; conventional versus computer tomography

International Nuclear Information System (INIS)

Heller, M.; Wenk, M.; Jend, H.H.

1984-01-01

Conventional tomography (T) and computer tomography (CT) were used for examining 97 artificial bone lesions at various sites. The purpose of the study was to determine how far CT can replace T in the diagnosis of skeletal abnormalities. The results have shown that modern CT, particularly in its high resolution form, equals T and provides additional information (substrate of a lesion, its relationship to neighbouring tissues, simultaneous demonstration of soft tissue etc.). These cannot be shown successfully by T. It follows that CT is indicated as the primary method of examination for lesions of the facial skeleton, skull base, spine, pelvis and, to some extent, extremities. (orig.) [de

Imaging of the digital arteries: Digital subtraction angiography versus conventional angiography

International Nuclear Information System (INIS)

Menanteau, B.P.; Treutenaere, J.M.; Marcus, C.; Ladam, V.; Gausserand, F.

1986-01-01

The authors report their experience with the use of digital subtraction angiography (DSA) and conventional angiography of the hand. Of the 95 patients in the study group, 80 underwent conventional angiography and 15 underwent DSA. They analyzed the studies with regard to the type and amount of contrast agent used, the number of radiographs needed, and the diagnostic quality of the images. Conventional angiography often requires general anesthesia, magnification, and pharmaco-angiographic techniques to improve the image-based diagnosis. In comparison with conventional angiography, intraarterial DSA is characterized by improved contrast sensitivity and inferior spatial resolution. However, DSA provides images as acceptable as those of conventional angiography. Smaller catheters can be used, and the examination is performed under local anesthesia. The authors conclude that intraarterial DSA is now the technique of choice for examining patients with chronic ischemia of the hand

Construction and identification of subtracted cDNA library in bone marrow cells of radon-exposed mice

International Nuclear Information System (INIS)

Li Jianxiang; Nie Jihua; Tong Jian; Fu Chunling; Zhou Jianwei

2008-01-01

Objective: To construct and identify subtracted cDNA library in bone marrow cells of mice exposed to radon inhalation. Methods: Adult male BALB/c mice, weighing 18-22 g, were placed in a multi- functional radon chamber. One group of mice was exposed to radon up to the accumulative dose of 105 work level month (WLM). The control group of mice was housed in a room with an accumulative dose of 1 WLM. To construct a subtracted cDNA library enriched with differentially expressed genes, the SMART technique and the suppression subtractive hybridization were performed. The obtained forward and reverse cDNA fragments were directly inserted into pMD18-T vector and transformed into E. coli JM109. The inserting cDNA fragments were screened by the blue-and-white blot screening and nested PCR of bacterium liquid. Results: The 244 of 285 white bacteria clones obtained randomly were positive clones contained 100-1100 bp inserted cDNA fragments. Conclusions: The forward and reverse subtracted cDNA library in bone marrow cells of mice exposed to radon inhalation is successfully constructed. (authors)

Trabecular bone analysis in CT and X-ray images of the proximal femur for the assessment of local bone quality.

Science.gov (United States)

Fritscher, Karl; Grunerbl, Agnes; Hanni, Markus; Suhm, Norbert; Hengg, Clemens; Schubert, Rainer

2009-10-01

Currently, conventional X-ray and CT images as well as invasive methods performed during the surgical intervention are used to judge the local quality of a fractured proximal femur. However, these approaches are either dependent on the surgeon's experience or cannot assist diagnostic and planning tasks preoperatively. Therefore, in this work a method for the individual analysis of local bone quality in the proximal femur based on model-based analysis of CT- and X-ray images of femur specimen will be proposed. A combined representation of shape and spatial intensity distribution of an object and different statistical approaches for dimensionality reduction are used to create a statistical appearance model in order to assess the local bone quality in CT and X-ray images. The developed algorithms are tested and evaluated on 28 femur specimen. It will be shown that the tools and algorithms presented herein are highly adequate to automatically and objectively predict bone mineral density values as well as a biomechanical parameter of the bone that can be measured intraoperatively.

Pathophysiologic basics and diagnostic limits of conventional bone scanning

International Nuclear Information System (INIS)

Schuemichen, C.; Dunkelmann, S.

2006-01-01

Normal bone scan demonstrates the physiological regional bone formation rate, which is related to bone remodeling and maintenance of calcium homeostasis. Osteotrope radiopharmaceuticals can be used as a perfusion marker as well as a marker of regional bone formation rate. Local hyperperfusion without increased bone formation is seen in disuse atrophy and reflex sympathic dystrophy, which are difficult to discriminate, local hypoperfusion is responsible for false negative results in osteomyelitis. A local increased bone formation rate is the substrate of a positive finding in bone fracture, inflammation, tumors, metastases and other lesions. In direct comparison with other imaging modalities (MRT, scintigraphy with non-osteotrope radiopharmaceutical and PET, but not CT and multislice-CT), planar bone scintigraphy shows an unexpected deficiency in sensitivity, which can be almost or completely overcome by using SPECT or even better 18 F-fluoride PET. These techniques will also improve specificity, which still is a weak point of bone scanning, despite improved imaging performance and a huge experience in this field. The introduction of SPECT/CT und PET/CT in bone scanning will be even more desirable for this reason. (orig.)

Digital subtraction radiography evaluation of the bone repair process of chronic apical periodontitis after root canal treatment.

Science.gov (United States)

Benfica e Silva, J; Leles, C R; Alencar, A H G; Nunes, C A B C M; Mendonça, E F

2010-08-01

To monitor radiographically the progress of bone repair within chronic periapical lesions after root canal treatment using digital subtraction radiography (DSR). Twelve patients with 17 single-rooted teeth with chronic apical periodontitis associated with an infected necrotic pulp were selected for root canal treatment. Periapical radiographs were taken before treatment (baseline) and immediately post-treatment, 45, 90, 135 and 180 days after treatment. The radiographic protocol included the use of individualized film holders with silicone bite blocks. The six radiographic images were digitized and submitted to digital subtraction using DSR software, resulting in five subtracted images (SI). Quantitative analysis of these SI was performed using Image Tool software to assess pixel value changes, considering a step-wedge as the gold standard and a cut-off value of 128 pixels. The aim was to identify any increase or decrease in mineral density in the region of the periapical lesion. A minor decrease in mineral density at the canal filling session and a significant progressive mineral gain in the following evaluations (P < 0.001) occurred. Pairwise comparison of pixel grey values revealed that only the 180-day follow-up differed significantly from the previous SI. Digital subtraction radiography is a useful method for evaluating the progress of bone repair after root canal treatment. Noticeable mineral gain was observed approximately 90 days after root canal filling and definite bone repair after 180 days.

68Ga-DOTA-NOC PET/CT in comparison with CT for the detection of bone metastasis in patients with neuroendocrine tumours

International Nuclear Information System (INIS)

Ambrosini, Valentina; Nanni, Cristina; Castellucci, Paolo; Allegri, Vincenzo; Montini, Giancarlo; Franchi, Roberto; Zompatori, Maurizio; Campana, Davide; Tomassetti, Paola; Rubello, Domenico; Fanti, Stefano

2010-01-01

To retrospectively evaluate the sensitivity, specificity and accuracy of 68 Ga-DOTA-NOC PET/CT and CT alone for the evaluation of bone metastasis in patients with neuroendocrine tumour (NET). From among patients with NET who underwent 68 Ga-DOTA-NOC PET/CT between April 2006 and November 2008 in our centre, 223 were included in the study. Criteria for inclusion were pathological confirmation of NET and a follow-up period of at least 10 months. PET and CT images were retrospectively reviewed by two nuclear medicine specialists and two radiologists, respectively, without knowledge of the patient history or the findings of other imaging modalities. PET data were compared with the CT findings. Interobserver agreement was evaluated in terms of the kappa score. Clinical and imaging follow-up were used as the standard of reference to evaluate the PET findings. PET was performed for staging (49/223), unknown primary tumour detection (24/223), restaging (32/223), restaging before radioimmunotherapy (1/223), evaluation during therapy (12/223), equivocal findings on conventional imaging (4/223 at the bone level; 61/223 at sites other than bone), and follow-up (40/223). A very high interobserver agreement was observed. CT detected at least one bone lesion in only 35 of 44 patients with a positive PET scan. In particular, PET showed more lesions in 20/35 patients, a lower number of lesions in 8/35, and the same number in 7/35. The characteristics of the lesions (sclerotic, lytic, mixed) on the basis of the CT report did not influence PET reading. PET revealed the presence of at least one bone metastasis in nine patients with a negative CT scan. Considering patients with a negative PET scan (179), CT showed equivocal findings at the bone level in three (single small sclerotic abnormality in two at the spine level, and bilateral small sclerotic abnormalities in the humeri, femurs and scapula). Clinical follow-up confirmed the PET findings in all patients; thus there were no false

Late iodine enhancement computed tomography with image subtraction for assessment of myocardial infarction

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Tanabe, Yuki; Kido, Teruhito; Kurata, Akira; Kouchi, Takanori; Fukuyama, Naoki; Yokoi, Takahiro; Miyagawa, Masao; Mochizuki, Teruhito [Ehime University Graduate School of Medicine, Department of Radiology, Toon City, Ehime (Japan); Uetani, Teruyoshi [Department of Cardiology, Ehime University Graduate School of Medicine, Toon City, Ehime (Japan); Yamashita, Natsumi [National Hospital Organization Shikoku Cancer Center, Department of Clinical Biostatistics, Section of Cancer Prevention and Epidemiology, Clinical Research Center, Matsuyama City, Ehime (Japan)

2018-03-15

To evaluate the feasibility of image subtraction in late iodine enhancement CT (LIE-CT) for assessment of myocardial infarction (MI). A comprehensive cardiac CT protocol and late gadolinium enhancement MRI (LGE-MRI) was used to assess coronary artery disease in 27 patients. LIE-CT was performed after stress CT perfusion (CTP) and CT angiography. Subtraction LIE-CT was created by subtracting the mask volume of the left ventricle (LV) cavity from the original LIE-CT using CTP dataset. The %MI volume was quantified as the ratio of LIE to entire LV volume, and transmural extent (TME) of LIE was classified as 0%, 1-24%, 25-49%, 50-74% or 75-100%. These results were compared with LGE-MRI using the Spearman rank test, Bland-Altman method and chi-square test. One hundred twenty-five (29%) of 432 segments were positive on LGE-MRI. Correlation coefficients for original and subtraction LIE-CT to LGE-MRI were 0.79 and 0.85 for %MI volume. Concordances of the 5-point grading scale between original and subtraction LIE-CT with LGE-MRI were 75% and 84% for TME; concordance was significantly improved using the subtraction technique (p <0.05). Subtraction LIE-CT allowed more accurate assessment of MI extent than the original LIE-CT. (orig.)

Comparison of FDG-PET/CT and bone scintigraphy for detection of bone metastases in breast cancer

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Hahn, Steffen; Heusner, Till; Forsting, Michael; Antoch, Gerald (Dept. of Diagnostic and Interventional Radiology and Neuroradiology, Univ. Hospital Essen, Univ. Duisburg-Essen, Essen (Germany)), email: steffen.hahn@uk-essen.de; Kuemmel, Sherko; Koeninger, Angelika (Dept. of Gynecology and Obstetrics, Univ. Hospital Essen, Univ. Duisburg-Essen, Essen (Germany)); Nagarajah, James; Mueller, Stefan; Boy, Christian; Bockisch, Andreas; Stahl, Alexander (Dept. of Nuclear Medicine, Univ. Hospital Essen, Univ. Duisburg-Essen, Essen (Germany))

2011-11-15

Background Bone scintigraphy is the standard procedure for the detection of bone metastases in breast cancer patients. FDG-PET/CT has been reported to be a sensitive tool for tumor staging in different malignant diseases. However, its accuracy for the detection of bone metastases has not been compared to bone scintigraphy. Purpose To compare whole-body FDG-PET/CT and bone scintigraphy for the detection of bone metastases on a lesion basis in breast cancer patients. Material and Methods Twenty-nine consecutive women (mean age 58 years, range 35-78 years) with histologically proven breast cancer were assessed with bone scintigraphy and whole-body FDG-PET/CT. Twenty-one patients (72%) were suffering from primary breast cancer and eight patients (28%) were in aftercare with a history of advanced breast cancer. Both imaging procedures were assessed for bone metastases by a radiologist and a nuclear medicine physician. Concordant readings between bone scintigraphy and FDG-PET/CT were taken as true. Discordant readings were verified with additional MRI imaging in all patients and follow-up studies in most patients. Results A total of 132 lesions were detected on bone scintigraphy, FDG-PET/CT or both. According to the reference standard, 70/132 lesions (53%) were bone metastases, 59/132 lesions (45%) were benign, and three lesions (2%) remained unclear. The sensitivity of bone scintigraphy was 76% (53/70) compared to 96% (67/70) for FDG-PET/CT. The specificity of bone scintigraphy and FDG-PET/CT was 95% (56/59) and 92% (54/59), respectively. According to the reference standard bone metastases were present in eight out of the 29 patients (28%), whereas 20 patients (69%) were free of bone metastases. One (3%) patient had inconclusive readings on both modalities as well as on MRI and follow-up studies. Bone scintigraphy and FDG-PET/CT correctly identified seven out of eight patients with bone metastases and 20 out of 20 patients free of metastases. Conclusion On a lesion

Cerebral bone subtraction CT angiography using 80 kVp and sinogram-affirmed iterative reconstruction: contrast medium and radiation dose reduction with improvement of image quality

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Nagayama, Yasunori [Kumamoto City Hospital, Department of Radiology, Kumamoto (Japan); Kumamoto University, Department of Diagnostic Radiology, Chuo-ku, Kumamoto (Japan); Nakaura, Takeshi; Oda, Seitaro; Kidoh, Masafumi; Utsunomiya, Daisuke; Yamashita, Yasuyuki [Kumamoto University, Department of Diagnostic Radiology, Chuo-ku, Kumamoto (Japan); Tsuji, Akinori; Urata, Joji; Furusawa, Mitsuhiro; Yuki, Hideaki; Hirarta, Kenichiro [Kumamoto City Hospital, Department of Radiology, Kumamoto (Japan)

2017-02-15

The purpose of this study was to evaluate the feasibility of a contrast medium (CM), radiation dose reduction protocol for cerebral bone-subtraction CT angiography (BSCTA) using 80-kVp and sinogram-affirmed iterative reconstruction (SAFIRE). Seventy-five patients who had undergone BSCTA under the 120- (n = 37) or the 80-kVp protocol (n = 38) were included. CM was 370 mgI/kg for the 120-kVp and 296 mgI/kg for the 80-kVp protocol; the 120- and the 80-kVp images were reconstructed with filtered back-projection (FBP) and SAFIRE, respectively. We compared effective dose (ED), CT attenuation, image noise, and contrast-to-noise ratio (CNR) of two protocols. We also scored arterial contrast, sharpness, depiction of small arteries, visibility near skull base/clip, and overall image quality on a four-point scale. ED was 62% lower at 80- than 120-kVp (0.59 ± 0.06 vs 1.56 ± 0.13 mSv, p < 0.01). CT attenuation of the internal carotid artery (ICA) and middle cerebral artery (MCA) was significantly higher on 80- than 120-kVp (ICA: 557.4 ± 105.7 vs 370.0 ± 59.3 Hounsfield units (HU), p < 0.01; MCA: 551.9 ± 107.9 vs 364.6 ± 62.2 HU, p < 0.01). The CNR was also significantly higher on 80- than 120-kVp (ICA: 46.2 ± 10.2 vs 36.9 ± 7.6, p < 0.01; MCA: 45.7 ± 10.0 vs 35.7 ± 9.0, p < 0.01). Visibility near skull base and clip was not significantly different (p = 0.45). The other subjective scores were higher with the 80- than the 120-kVp protocol (p < 0.05). The 80-kVp acquisition with SAFIRE yields better image quality for BSCTA and substantial reduction in the radiation and CM dose compared to the 120-kVp with FBP protocol. (orig.)

CT-diagnosis of temporal bone trauma

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Valavanis, A.; Stuckmann, G.; Antonucci, F.; Schubiger, O.

1986-02-01

73 patients with 78 fractures of the temporal bone were examined by high-resolution computed tomography (CT). Analysis of the CT-findings disclosed 55 longitudinal, 12 transverse, 8 combined and 3 atypical fractures. For determination of the fracture type, axial sections usually proved sufficient. However, for precise topographic analysis of the course of the fracture additional coronal sections were necessary in most of the cases. In the radiologic evaluation of temporal bone fractures detection of associated. Complications is clinically important since these can be surgically corrected. In this series 20 lesions of the ossicular chain were demonstrated by the combined performance of axial and coronal sections and sagittal reformations. High resolution CT demonstrated a lesion of the facial nerve canal in 79% of a patient group with traumatic facial nerve palsy. The most frequent site of injury of the facial nerve canal was the region of the geniculate ganglion. With the use of metrizaminde-CT-cisternography the site of cerebrospinal fluid leakage was demonstrated in 7 of 9 patients with liquorrhea. It is concluded that high-resolution CT is the radiologic method of choice for both topographic evaluation of temporal bone fractures and detection and precise localization of fracture-complications. (orig.).

Bone formation rather than inflammation reflects ankylosing spondylitis activity on PET-CT: a pilot study.

Science.gov (United States)

Bruijnen, Stefan T G; van der Weijden, Mignon A C; Klein, Joannes P; Hoekstra, Otto S; Boellaard, Ronald; van Denderen, J Christiaan; Dijkmans, Ben A C; Voskuyl, Alexandre E; van der Horst-Bruinsma, Irene E; van der Laken, Conny J

2012-04-02

Positron Emission Tomography - Computer Tomography (PET-CT) is an interesting imaging technique to visualize Ankylosing Spondylitis (AS) activity using specific PET tracers. Previous studies have shown that the PET tracers [18F]FDG and [11C](R)PK11195 can target inflammation (synovitis) in rheumatoid arthritis (RA) and may therefore be useful in AS. Another interesting tracer for AS is [18F]Fluoride, which targets bone formation. In a pilot setting, the potential of PET-CT in imaging AS activity was tested using different tracers, with Magnetic Resonance Imaging (MRI) and conventional radiographs as reference. In a stepwise approach different PET tracers were investigated. First, whole body [18F]FDG and [11C](R)PK11195 PET-CT scans were obtained of ten AS patients fulfilling the modified New York criteria. According to the BASDAI five of these patients had low and five had high disease activity. Secondly, an extra PET-CT scan using [18F]Fluoride was made of two additional AS patients with high disease activity. MRI scans of the total spine and sacroiliac joints were performed, and conventional radiographs of the total spine and sacroiliac joints were available for all patients. Scans and radiographs were visually scored by two observers blinded for clinical data. No increased [18F]FDG and [11C](R)PK11195 uptake was noticed on PET-CT scans of the first 10 patients. In contrast, MRI demonstrated a total of five bone edema lesions in three out of 10 patients. In the two additional AS patients scanned with [18F]Fluoride PET-CT, [18F]Fluoride depicted 17 regions with increased uptake in both vertebral column and sacroiliac joints. In contrast, [18F]FDG depicted only three lesions, with an uptake of five times lower compared to [18F]Fluoride, and again no [11C](R)PK11195 positive lesions were found. In these two patients, MRI detected nine lesions and six out of nine matched with the anatomical position of [18F]Fluoride uptake. Conventional radiographs showed structural

Reproducibility of CT bone dosimetry: Operator versus automated ROI definition

International Nuclear Information System (INIS)

Louis, O.; Luypaert, R.; Osteaux, M.; Kalender, W.

1988-01-01

Intrasubject reproducibility with repeated determination of vertebral mineral density from a given set of CT images was investigated. The region of interest (ROI) in 10 patient scans was selected by four independent operators either manually or with an automated procedure separating cortical and spongeous bone, the operators being requested to interact in ROI selection. The mean intrasubject variation was found to be much lower with the automated process (0.3 to 0.6%) than with the conventional method (2.5 to 5.2%). In a second study, 10 patients were examined twice to determine the reproducibility of CT slice selection by the operator. The errors were of the same order of magnitude as in ROI selection. (orig.)

Using Micro-CT Derived Bone Microarchitecture to Analyze Bone Stiffness - A Case Study on Osteoporosis Rat Bone

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Yuchin eWu

2015-05-01

Full Text Available Micro-computed tomography images can be used to quantitatively represent bone geometry through a range of computed attenuation-based parameters. Nonetheless, those parameters remain indirect indices of bone micro-architectural strength and require further computational tools to interpret bone structural stiffness and potential for mechanical failure. Finite element analysis (FEA can be applied to measure trabecular bone stiffness and potentially predict the location of structural failure in preclinical animal models of osteoporosis, although that procedure from image segmentation of micro-CT derived bone geometry to FEA is often challenging and computationally expensive, resulting in failure of the model to build. Notably, the selection of resolution and threshold for bone segmentation are key steps that greatly affect computational complexity and validity. In the following study, we evaluated an approach whereby Micro-CT derived greyscale attenuation and segmentation data guided the selection of trabecular bone for analysis by FEA. We further correlated those FEA results to both two and three dimensional bone microarchitecture from sham and ovariectomized (OVX rats (n=10/group. A virtual cylinder of vertebral trabecular bone 40% in length from the caudal side was selected for FEA because micro-CT based image analysis indicated the largest differences in microarchitecture between the two groups resided there. Bone stiffness was calculated using FEA and statistically correlated with the three dimensional values of bone volume/tissue volume, bone mineral density, fractal dimension, trabecular separation and trabecular bone pattern factor. Our method simplified the process for the assessment of trabecular bone stiffness by FEA from Micro-CT images and highlighted the importance of bone microarchitecture in conferring significantly increased bone quality capable of resisting failure due to increased mechanical loading.

SPECT-CT bone scintigraphy in cancer patients

International Nuclear Information System (INIS)

Sergieva, S; Alexandrova, A.; Nikolova, N.; Dimcheva, M.; Baichev, G.

2012-01-01

Full text: Introduction: SPECT-CT study allows the precise correlation between functional and morphological data on the same image. Methods: Whole body bone scan (WBBS) is a diagnostic modality still firmly established as a valuable tool to assess skeleton abnormalities. CT is an imaging method for characterizing destruction of the bone spongy lesions, their consolidation or calcium accumulation. This fact allows differentiation of the osteolytic metastases from the osteosclerotic and mixed lesions and also from degenerative ones. Whole body bone scan followed by SPECT-CT scanning increases the accuracy of the study and potentially accelerates the diagnosis of the patient based on a single imaging session. This is especially important in cancer patients. Results and discussion: After retrospectively review of WBBS and SPECT-CT fused images 141 bone lesions in 89 pts were analyzed The skeletal findings with previously uncertain character were classified as definitely benign, indeterminate or definitely malignant. 1. 47 (33%) of all lesions in 36 pts could be correlated with benign degenerative findings on SPECT-CT images. 5 (3%) lesions in 3 of these pts were indeterminate on the SPECT-CT images. They were localized in the area of articulation parts and corpus of the thoracic vertebra and ribs. After additional MRT examination and 6 months follow-up these changes were considered degenerative: osteopathy changes and presence of spondyloarthrosis and osteochondrosis; compression fractures due to advanced osteoporosis. These pts were with prolonged chormono/chemotherapy; chronic inflammatory disease of the coxofemoral articulation, coxarthrosis, aseptic necrosis of the femoral head and postoperative sacroiliitis; post-traumatic fractures or surgical intervention; hyperplastic degenerative lesions in the skeleton and asymmetrical pelvic bone structures due to M. Paget. 2. 41 (28,1%) single osseous metastatic spots (up to 3 foci) were scanned in 31 pts. 3. 13 (10

Real-time out-of-plane artifact subtraction tomosynthesis imaging using prior CT for scanning beam digital x-ray system

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Wu, Meng, E-mail: mengwu@stanford.edu [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Fahrig, Rebecca [Department of Radiology, Stanford University, Stanford, California 94305 (United States)

2014-11-01

Purpose: The scanning beam digital x-ray system (SBDX) is an inverse geometry fluoroscopic system with high dose efficiency and the ability to perform continuous real-time tomosynthesis in multiple planes. This system could be used for image guidance during lung nodule biopsy. However, the reconstructed images suffer from strong out-of-plane artifact due to the small tomographic angle of the system. Methods: The authors propose an out-of-plane artifact subtraction tomosynthesis (OPAST) algorithm that utilizes a prior CT volume to augment the run-time image processing. A blur-and-add (BAA) analytical model, derived from the project-to-backproject physical model, permits the generation of tomosynthesis images that are a good approximation to the shift-and-add (SAA) reconstructed image. A computationally practical algorithm is proposed to simulate images and out-of-plane artifacts from patient-specific prior CT volumes using the BAA model. A 3D image registration algorithm to align the simulated and reconstructed images is described. The accuracy of the BAA analytical model and the OPAST algorithm was evaluated using three lung cancer patients’ CT data. The OPAST and image registration algorithms were also tested with added nonrigid respiratory motions. Results: Image similarity measurements, including the correlation coefficient, mean squared error, and structural similarity index, indicated that the BAA model is very accurate in simulating the SAA images from the prior CT for the SBDX system. The shift-variant effect of the BAA model can be ignored when the shifts between SBDX images and CT volumes are within ±10 mm in the x and y directions. The nodule visibility and depth resolution are improved by subtracting simulated artifacts from the reconstructions. The image registration and OPAST are robust in the presence of added respiratory motions. The dominant artifacts in the subtraction images are caused by the mismatches between the real object and the prior CT

CT and conventional radiographic techniques in interstitial pulmonary disease

International Nuclear Information System (INIS)

Leipner, N.; Schueller, H.; Uexkuell-Gueldenband, V. v.; Schlolaut, K.H.; Overlack, A.; Bonn Univ.

1988-01-01

One hundred and sixty-four patients with pulmonary fibrosis were examined by CT and by conventional radiological methods. Sixty patients had asbestosis, thirty-nine silicosis, forty sarcoidosis and twenty-five had idiopathic pulmonary fibrosis. CT is superior to conventional radiography in evaluating interstitial pulmonary changes, particularly of the pleura and the lung parenchyma. In sixty-nine patients there were some findings which could only be demonstrated by CT. In asbestosis, silicosis and sarcoidosis the CT classification of the lung parenchyma which we have suggested produces significantly better correlation with vital capacity than can be achieved from conventional chest films, according to the guidelines of the I.L.O. (orig./GDG) [de

99mTc-RBC subtraction scintigraphy

International Nuclear Information System (INIS)

Inagaki, Syoichi; Tonami, Syuichi; Yasui, Masakazu; Kuranishi, Makoto; Sugishita, Kouki; Nakamura, Mamoru

1994-01-01

Sequential abdominal scintigrams with 99m Tc-labelled red blood cells (RBC) were subtracted for observing a site of gastrointestinal bleeding and calculating the bleeding rate. This method is technically very easy and can detect the site of bleeding with the minimum rate, as low as 0.2 ml/min., in a phantom experiment. In 23 cases with final diagnosis of gastrointestinal bleeding, conventional non-subtraction scintigraphy detected only 30% (7/23), but subtraction scintigraphy detected 61% (14/23). It was concluded that subtraction scintigraphy had higher sensitivity than conventional scintigraphy for early diagnosing bleeding. A combination of non-subtraction and subtraction scintigraphy is recommended to detect a site of gastrointestinal bleeding in a clinical setting. (author)

Digital subtraction ventriculography for assessment of global and regional leftventricular parameters in comparison to conventional contrast ventriculography

International Nuclear Information System (INIS)

Eichstaedt, H.; Langer, M.; Felix, R.

1984-01-01

Since May 1982 we studied more than 100 patients with heart diseases by means of digital angiography, out of them 46 patients with a history of transmural myocardial infarction were selected. Urografin 76, 30 ml, was administered at a flow rate of 18 ml/s by means of a catheter in the superior vena cava during digital subtraction ventriculography. Results were compared with conventional contrast ventriculograms. The correlation coefficient was r=0.93 (p 0.001) for determination of ejection fraction with both methods. The data in individual cases suggest that DSV is more sensitive than conventional contrast ventriculography in determination of severely reduced ejection fractions. The methods are practically identical in qualitative evaluation of disorders of regional wall motion in the anterolateral region, while DSV is more sensitive than conventional ventriculography in evaluating the apical region. Sensitivity was 85.7% when the two methods were compared in evaluation of the inferior region of the left ventricle. Both methods are identical in demonstration of severely deformed ventricles. Digital subtraction ventriculography may replace conventional contrast ventriculography in some of situations discussed above. (orig.)

Quantitative analysis of alveolar bone change following implant placement using intraoral radiographic subtraction

International Nuclear Information System (INIS)

Kimura, Hiroyuki; Kanda, Shigenobu; Tanaka, Takemasa

2002-01-01

The purpose of this study was to develop a procedure for quantitative analysis using intraoral radiographs of alveolar bone after placement of dental implants and to consider the validity of the method. We evaluated the ten patients (2 males and 8 females, average age: 48.4 years-old), who were treated with dental implant operation in the site of mandibular molar region, since October of 1999 until September of 2000 in Kimura Dental Clinic (Kumamoto, Japan). We evaluated the intraoral radiographs taken pre- and post- operatively and at follow-up examination. To detect alveolar bone change on radiograph, we adopted the digital subtraction method. Although the radiographs were taken under an ordinary technique with cone indicator, we did not apply the standardized technique with fixing material customized for each patient. Therefore, we used geometric correction and density compensation before subtraction. We assessed the basic statistical values (mean, variance, kurtosis and skewness) of the region of interest (ROI) of the subtracted images. Also, we noted PPD (probing pocket depth) and BOP (bleeding on probing) at each site as indicators of clinical findings and all implanted sites were classified according to the PPD or BOP, i.e. PPD increased group ''PPD (+)'' and PPD stable group ''PPD (-)'', likewise BOP positive group ''BOP (+)'' and negative group ''BOP (-)''. We considered the statistical values of ROI in each group and compared these findings. Mean and variance values of PPD (+) were higher than those of PPD (-) and there was a significant difference in mean value (p=0.031). Similarly, mean and variance values of BOP (+) were statistically higher than those of BOP (-) (p=0.041 and p=0.0087, respectively). Concerning kurtosis and skewness, there was no difference between PPD (+) and PPD (-), or between BOP (+) and BOP (-). Using our method, the radiographs taken for follow-up examination could be assessed quantitatively. It is suggested that geometric

Evaluation of bone viability in patients after girdlestone arthroplasty: comparison of bone SPECT/CT and MRI

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Diederichs, G.; Collettini, F.; Hamm, B.; Makowski, M.R. [Department of Radiology, Berlin (Germany); Hoppe, P.; Brenner, W. [Department of Nuclear Medicine, Berlin (Germany); Wassilew, G. [Department of Orthopedic Surgery, Berlin (Germany)

2017-09-15

To test the diagnostic performance of bone SPECT/CT and MRI for the evaluation of bone viability in patients after girdlestone-arthroplasty with histopathology used as gold standard. In this cross-sectional study, patients after girdlestone-arthroplasty were imaged with single-photon-emission-computed-tomography/computed-tomography (SPECT/CT) bone-scans using 99mTc-DPD. Additionally, 1.5 T MRI was performed with turbo-inversion-recovery-magnitude (TIRM), contrast-enhanced T1-fat sat (FS) and T1-mapping. All imaging was performed within 24 h prior to revision total-hip-arthroplasty in patients with a girdlestone-arthroplasty. In each patient, four standardized bone-tissue-biopsies (14 patients) were taken intraoperatively at the remaining acetabulum superior/inferior and trochanter major/minor. Histopathological evaluation of bone samples regarding bone viability was used as gold standard. A total of 56 bone-segments were analysed and classified as vital (n = 39) or nonvital (n = 17) by histopathology. Mineral/late-phase SPECT/CT showed a high sensitivity (90%) and specificity (94%) to distinguish viable and nonviable bone tissue. TIRM (sensitivity 87%, specificity 88%) and contrast-enhanced T1-FS (sensitivity 90%, specificity 88%) also achieved a high sensitivity and specificity. T1-mapping achieved the lowest values (sensitivity 82%, specificity 82%). False positive results in SPECT/CT and MRI resulted from small bone fragments close to metal artefacts. Both bone SPECT/CT and MRI allow a reliable differentiation between viable and nonviable bone tissue in patients after girdlestone arthroplasty. The findings of this study could also be relevant for the evaluation of bone viability in the context of avascular bone necrosis. (orig.)

Evaluation of bone viability in patients after girdlestone arthroplasty: comparison of bone SPECT/CT and MRI

International Nuclear Information System (INIS)

Diederichs, G.; Collettini, F.; Hamm, B.; Makowski, M.R.; Hoppe, P.; Brenner, W.; Wassilew, G.

2017-01-01

To test the diagnostic performance of bone SPECT/CT and MRI for the evaluation of bone viability in patients after girdlestone-arthroplasty with histopathology used as gold standard. In this cross-sectional study, patients after girdlestone-arthroplasty were imaged with single-photon-emission-computed-tomography/computed-tomography (SPECT/CT) bone-scans using 99mTc-DPD. Additionally, 1.5 T MRI was performed with turbo-inversion-recovery-magnitude (TIRM), contrast-enhanced T1-fat sat (FS) and T1-mapping. All imaging was performed within 24 h prior to revision total-hip-arthroplasty in patients with a girdlestone-arthroplasty. In each patient, four standardized bone-tissue-biopsies (14 patients) were taken intraoperatively at the remaining acetabulum superior/inferior and trochanter major/minor. Histopathological evaluation of bone samples regarding bone viability was used as gold standard. A total of 56 bone-segments were analysed and classified as vital (n = 39) or nonvital (n = 17) by histopathology. Mineral/late-phase SPECT/CT showed a high sensitivity (90%) and specificity (94%) to distinguish viable and nonviable bone tissue. TIRM (sensitivity 87%, specificity 88%) and contrast-enhanced T1-FS (sensitivity 90%, specificity 88%) also achieved a high sensitivity and specificity. T1-mapping achieved the lowest values (sensitivity 82%, specificity 82%). False positive results in SPECT/CT and MRI resulted from small bone fragments close to metal artefacts. Both bone SPECT/CT and MRI allow a reliable differentiation between viable and nonviable bone tissue in patients after girdlestone arthroplasty. The findings of this study could also be relevant for the evaluation of bone viability in the context of avascular bone necrosis. (orig.)

Early small-bowel ischemia: dual-energy CT improves conspicuity compared with conventional CT in a swine model.

Science.gov (United States)

Potretzke, Theodora A; Brace, Christopher L; Lubner, Meghan G; Sampson, Lisa A; Willey, Bridgett J; Lee, Fred T

2015-04-01

To compare dual-energy computed tomography (CT) with conventional CT for the detection of small-bowel ischemia in an experimental animal model. The study was approved by the animal care and use committee and was performed in accordance with the Guide for Care and Use of Laboratory Animals issued by the National Research Council. Ischemic bowel segments (n = 8) were created in swine (n = 4) by means of surgical occlusion of distal mesenteric arteries and veins. Contrast material-enhanced dual-energy CT and conventional single-energy CT (120 kVp) sequences were performed during the portal venous phase with a single-source fast-switching dual-energy CT scanner. Attenuation values and contrast-to-noise ratios of ischemic and perfused segments on iodine material-density, monospectral dual-energy CT (51 keV, 65 keV, and 70 keV), and conventional 120-kVp CT images were compared. Linear mixed-effects models were used for comparisons. The attenuation difference between ischemic and perfused segments was significantly greater on dual-energy 51-keV CT images than on conventional 120-kVp CT images (mean difference, 91.7 HU vs 47.6 HU; P conventional CT by increasing attenuation differences between ischemic and perfused segments on low-kiloelectron volt and iodine material density images. © RSNA, 2014.

Multi-slice CT for visualization of acute pulmonary embolism: single breath-hold subtraction technique

International Nuclear Information System (INIS)

Wildberger, J.E.; Mahnken, A.H.; Spuentrup, E.; Guenther, R.W.; Klotz, E.; Ditt, H.

2005-01-01

Purpose: the purpose of our preliminary animal study was to evaluate the feasibility of a new subtraction technique for visualization of perfusion defects within the lung parenchyma in segmental and subsegmental pulmonary embolism (PE). Materials and methods: in three healthy pigs, PE were artificially induced by fresh human clot material. Within a single breath-hold, CT angiography (CTA) was performed on a 16-slice multi-slice CT scanner (SOMATOM Sensation 16; Siemens, Forchheim, Germany) before and after intravenous application of 80 mL of contrast-medium, followed by a saline chaser. Scan parameters were 120 kV and 100 mAs eff. , using a collimation of 16 x 1.5 mm and a table speed/rot. of 36 mm (pitch: 1.5; rotation time: 0.5 s). A new 3D subtraction technique was developed, which is based on automated segmentation, non-linear spatial filtering and non-rigid registration. Data were analysed using a color-encoded ''compound view'' of parenchymal enhancement and CTA information displayed in axial, coronal and sagittal orientation. Results: subtraction was technically feasible in all three data sets. The mean scan time for each series was 4.7 s, interscan delay was 14.7 s, respectively. Therefore, an average breath-hold of approximately 24 s was required for the overall scanning procedure. Downstream of occluded segmental and subsegmental arteries, perfusion defects were clearly assessable, showing lower or missing enhancement compared to normally perfused lung parenchyma. In all pigs, additional peripheral areas with triangular shaped perfusion defects were delineated, considered typical for PE. Conclusions: our initial results from the animal model studied slow that perfusion imaging of PE is feasible within a single breath-hold. It allows a comprehensive assessment of perfusion deficits as the direct proof of a pulmonary embolus, can be combined with an indirect visual quantification of the density changes in the adjacent lung tissue. (orig.)

Diagnostic performance of [18F] FDG PET-CT compared to bone scintigraphy for the detection of bone metastases in lung cancer patients

International Nuclear Information System (INIS)

RODRIGUES, Margarida; STARK, Hannes; RENDL, Gundula; RETTENBACHER, Lukas; PIRICH, Christian; DATZ, Lidwina; STUDNICKA, Michael

2016-01-01

Accurate staging of lung cancer is essential for effective patient management and selection of appropriate therapeutic strategy. The aim of this paper was to compare the value of bone scintigraphy and FDG PET-CT for detecting bone metastases in lung cancer patients and the impact of these modalities in disease staging. One hundred sixty-four lung cancer patients who had undergone both FDG PET-CT and bone scintigraphy within 14 days were included into this study. The analysis of FDG PET-CT and bone scintigraphy was carried out patient- and lesion-based. One hundred twenty-one patients were negative and 43 patients positive for bone metastases. FDG PET-CT found bone metastases in 42/43 patients and bone scintigraphy in 38/43 patients. Sensitivity, specificity and accuracy of FDG PET-CT and bone scintigraphy for detecting bone metastases were 97.7%, 100% and 99.4%, and 87.8%, 97.5% and 94.2%, respectively. FDG PET-CT identified 430 bone metastases and bone scintigraphy 246 bone metastases. Skull was the only region where bone scintigraphy identified more lesions than FDG PET-CT. Based on both scintigraphic modalities disagreement concerning disease stage was found in 3 patients. In conclusion, FDG PET-CT yielded a higher sensitivity, specificity and accuracy than bone scintigraphy for identifying bone metastases in lung cancer patients. FDG PET-CT thus can be recommended for initial staging of lung cancer patients without applying bone scintigraphy for the detection of bone metastases.

Synchrotron μCT Imaging of Bone, Titanium implants and Bone Substitutes -a Systematic Review of the Literature

DEFF Research Database (Denmark)

Neldam, Camilla Albeck; Pinholt, Else Marie

2014-01-01

Today x-ray micro computer tomography (μCT) imaging is used to investigate bone microarchitecture. μCT imaging is obtained by polychromatic x-ray beams, resulting in images with beam hardening artifacts, resolution levels at 10 μm, geometrical blurring, and lack of contrasts. When μCT is coupled...... to synchrotron sources (SRμCT) a spatial resolution up to one tenth of a μm may be achieved. A review of the literature concerning SRμCT was performed to investigate its usability and its strength in visualizing fine bone structures, vessels, and microarchitecture of bone. Although mainly limited to in vitro...... examinations, SRμCT is considered as a gold standard to image trabecular bone microarchitecture since it is possible in a 3D manner to visualize fine structural elements within mineralized tissue such as osteon boundaries, rods and plates structures, cement lines, and differences in mineralization...

Malignancy rate of biopsied suspicious bone lesions identified on FDG PET/CT

Energy Technology Data Exchange (ETDEWEB)

Adams, Hugo J.A.; Kwee, Thomas C. [University Medical Center Utrecht, Department of Radiology and Nuclear Medicine, Utrecht (Netherlands); Klerk, John M.H. de [Meander Medical Center, Department of Nuclear Medicine, Amersfoort (Netherlands); Heggelman, Ben G.F. [Meander Medical Center, Department of Radiology, Amersfoort (Netherlands); Dubois, Stefan V. [Meander Medical Center, Department of Pathology, Amersfoort (Netherlands)

2016-07-15

To determine the malignancy rate of bone lesions identified on FDG PET/CT in patients who have undergone CT-guided biopsy because of the suspicion of malignancy. This single-centre retrospective study spanned eight consecutive years and included all patients who underwent both FDG PET/CT and CT-guided bone biopsy because of the suspicion of malignancy. The positive predictive value (PPV) for malignancy was calculated, and different patient and imaging characteristics were compared between malignant and benign bone lesions. Of 102 included patients with bone lesions that all showed FDG uptake exceeding mediastinal uptake, bone biopsy showed a malignant lesion in 91 patients, yielding a PPV for malignancy of 89.2 % (95 % CI 81.7 - 93.9 %). In the 94 patients with bone lesions that showed FDG uptake exceeding liver uptake, bone biopsy showed a malignant lesion in 83 patients, yielding a PPV for malignancy of 88.3 % (95 % CI 80.1 - 93.5 %). Higher age, bone marrow replacement of the lesion seen on CT, expansion of the lesion seen on CT, and presence of multifocal lesions on FDG PET/CT were significantly more frequent in patients with malignant lesions than in those with benign bone lesions (P = 0.044, P = 0.009, P = 0.015, and P = 0.019, respectively). Furthermore, there was a trend towards a higher incidence of cortical destruction (P = 0.056) and surrounding soft tissue mass (P = 0.063) in patients with malignant bone lesions. The PPV for malignancy of suspicious bone lesions identified on FDG PET/CT is not sufficiently high to justify changes in patient management without histopathological confirmation. Nevertheless, ancillary patient and imaging characteristics may increase the likelihood of a malignant bone lesion. (orig.)

Bone scan and SPECT/CT findings in marble bone disease

International Nuclear Information System (INIS)

Kapoor, Jiten; Joshi, Prathamesh; Lele, Vikram

2012-01-01

Marble bone disease or osteopetrosis, is a rare inborn disorder characterized by the failure of osteoclasts to resorb bone. Overall incidence of the disease is estimated to be 1 case in 100,000-500,000 population. Whereas the radiographic features of the disease are well known, information on bone scan imaging is sparse in the literature. We present technitium 99m methylene diphosphonate ( 99m Tc MDP) bone scan features of osteopetrosis, along with single photon emission computed tomography-computed tomography(SPECT/CT) correlation in a young male.

Bone scan and SPECT/CT findings in marble bone disease

Energy Technology Data Exchange (ETDEWEB)

Kapoor, Jiten; Joshi, Prathamesh; Lele, Vikram [Jaslok Hospital and Research Centre, Woril (India)

2012-03-15

Marble bone disease or osteopetrosis, is a rare inborn disorder characterized by the failure of osteoclasts to resorb bone. Overall incidence of the disease is estimated to be 1 case in 100,000-500,000 population. Whereas the radiographic features of the disease are well known, information on bone scan imaging is sparse in the literature. We present technitium 99m methylene diphosphonate ({sup 99m}Tc MDP) bone scan features of osteopetrosis, along with single photon emission computed tomography-computed tomography(SPECT/CT) correlation in a young male.

FDG PET/CT in pediatric primary bone tumours: comparison with conventional imaging (CI) and management impact assesment

International Nuclear Information System (INIS)

Stege, Claudia; London, Kevin; Cross, Siobhan; Howman-Giles, Robert; Onikul, Ella; Graf, Nicole; Pozza, L.D.

2009-01-01

Full text: To evaluate PET/CT in pediatric primary bone tumours (PBT), the accuracy, clinical impact, prognostic indicators in predicting tumour response to therapy and determining epiphyseal involvement were compared to Cl. Methods: A retrospective review of PET/CT scans with CI was performed. Lesions were compared to a reference standard: histopathology or follow up >6 mths. Pt based analysis was performed for clinical impact. Prognostic indicators (SUYmax, tumour size) were compared to histopathology response post chemotherapy. Results: 43 pts (average 12.9 yrs) with osteosarcoma (I 8), Ewing's sarcoma (21), PNE (4) were analysed. 109 PET/CT scans with CI scans were evaluated (371 lesions). 33 lesions were discordant. Accuracy of PET/CT was higher for all lesions than CI (95% vs92%) but sensitivity was lower (79% vs 83%). Excluding lung lesions, sensitivities increased for PET/CT and CI (92% vs 89%). 9pts had PET/CT staging and follow up with histopathological evaluation post chemotherapy: 2pts poor responders, 7 good responders. Good responders had a higher SUYmax at diagnosis compared to poor responders (av 13.84 vs 7.95) but reduced more [10.5(70%) vs 3.5( 45%)]following chemotherapy. There were no false negatives for epiphyseal involvement for PET/CT and CI but one PET/CT was false positive. Conclusion: PET/CT is less sensitive in small lung lesions, but more sensitive in other areas compared to Cl. SUYmax at diagnosis is a poor predictor of response, but percent decrease post therapy was associated with therapeutic response. Change in tumour size on MR is a poor predictor of response. There is improved clinical impact with PET/CT in patient management.

Gaucher's disease. Plain radiography, US, CT and MR diagnosis of lungs, bone and liver lesions

Energy Technology Data Exchange (ETDEWEB)

Hainaux, B.; Christophe, C.; Hanquinet, S.; Perlmutter, N. (Free Univ. of Brussels (Belgium). Dept. of Pediatric Radiology)

1992-04-01

We report our observations made by conventional radiography, ultrasound, computerized tomography (CT), and magnetic resonance imaging (MRI) on a 3 1/2-year-old girl with Gaucher's disease. The interest of the case consists in the exceptional lungs involvement, the demonstration by MRI of the bone marrow involvement and the necrosis and fibrosis of the liver, as shown by CT. This liver complication has been previously reported only once. (orig.).

Digital subtraction CT angiography for the detection of posterior inferior cerebellar artery aneurysms: comparison with digital subtraction angiography

Energy Technology Data Exchange (ETDEWEB)

Chen, Guo Zhong; Luo, Song; Zhou, Chang Sheng; Zhang, Long Jiang; Lu, Guang Ming [Jinling Hospital, Medical School of Nanjing University, Department of Medical Imaging, Nanjing, Jiangsu (China)

2017-09-15

To evaluate the diagnostic accuracy of digital subtraction CT angiography (DS-CTA) in detecting posterior inferior cerebellar artery (PICA) aneurysms with digital subtraction angiography (DSA) as reference standard. A total of 115 patients, including 56 patients diagnosed with PICA aneurysms by CTA or DSA and 59 non-PICA-aneurysm patients were included in this retrospective study. All patients underwent DS-CTA and DSA. The site of PICA aneurysms and the pattern of haemorrhage were analysed. Sensitivity and specificity of DS-CTA without and with combining haemorrhage pattern in diagnosing PICA aneurysms were evaluated on a per patient and per aneurysm basis with DSA. Of 115 patients, 56 patients (48.7%) had 61 PICA aneurysms (size range, 1.1-13.5 mm; mean size, 4.9 ± 2.8 mm) on DSA. The sensitivity and specificity in depicting PICA aneurysms were 89.3% and 96.6% on a per patient basis and 90.2% and 93.4% on a per aneurysm basis, while the corresponding values were 94.6% and 96.6% on a per patient basis and 95.1% and 93.4% on a per aneurysm basis when combining with haemorrhage site. DS-CTA has a high sensitivity and specificity in detecting PICA aneurysms compared with DSA. It may be helpful for clinical diagnosis of PICA aneurysms to combine with haemorrhage sites. (orig.)

Synchrotron μCT imaging of bone, titanium implants and bone substitutes - a systematic review of the literature.

Science.gov (United States)

Neldam, Camilla Albeck; Pinholt, Else Marie

2014-09-01

Today X-ray micro computer tomography (μCT) imaging is used to investigate bone microarchitecture. μCT imaging is obtained by polychromatic X-ray beams, resulting in images with beam hardening artifacts, resolution levels at 10 μm, geometrical blurring, and lack of contrasts. When μCT is coupled to synchrotron sources (SRμCT) a spatial resolution up to one tenth of a μm may be achieved. A review of the literature concerning SRμCT was performed to investigate its usability and its strength in visualizing fine bone structures, vessels, and microarchitecture of bone. Although mainly limited to in vitro examinations, SRμCT is considered as a gold standard to image trabecular bone microarchitecture since it is possible in a 3D manner to visualize fine structural elements within mineralized tissue such as osteon boundaries, rods and plates structures, cement lines, and differences in mineralization. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

18F-FDG PET/CT for initial staging in breast cancer patients. Is there a relevant impact on treatment planning compared to conventional staging modalities?

International Nuclear Information System (INIS)

Krammer, J.; Schnitzer, A.; Kaiser, C.G.; Buesing, K.A.; Schoenberg, S.O.; Wasser, K.; Sperk, E.; Brade, J.; Wasgindt, S.; Suetterlin, M.; Sutton, E.J.

2015-01-01

To evaluate the impact of whole-body 18 F-FDG PET/CT on initial staging of breast cancer in comparison to conventional staging modalities. This study included 102 breast cancer patients, 101 patients were eligible for evaluation. Preoperative whole-body staging with PET/CT was performed in patients with clinical stage ≥ T2 tumours or positive local lymph nodes (n = 91). Postoperative PET/CT was performed in patients without these criteria but positive sentinel lymph node biopsy (n = 10). All patients underwent PET/CT and a conventional staging algorithm, which included bone scan, chest X-ray and abdominal ultrasound. PET/CT findings were compared to conventional staging and the impact on therapeutic management was evaluated. PET/CT led to an upgrade of the N or M stage in overall 19 patients (19 %) and newly identified manifestation of breast cancer in two patients (2 %). PET/CT findings caused a change in treatment of 11 patients (11 %). This is within the range of recent studies, all applying conventional inclusion criteria based on the initial T and N status. PET/CT has a relevant impact on initial staging and treatment of breast cancer when compared to conventional modalities. Further studies should assess inclusion criteria beyond the conventional T and N status, e.g. tumour grading and receptor status. (orig.)

A LabVIEW Platform for Preclinical Imaging Using Digital Subtraction Angiography and Micro-CT.

Science.gov (United States)

Badea, Cristian T; Hedlund, Laurence W; Johnson, G Allan

2013-01-01

CT and digital subtraction angiography (DSA) are ubiquitous in the clinic. Their preclinical equivalents are valuable imaging methods for studying disease models and treatment. We have developed a dual source/detector X-ray imaging system that we have used for both micro-CT and DSA studies in rodents. The control of such a complex imaging system requires substantial software development for which we use the graphical language LabVIEW (National Instruments, Austin, TX, USA). This paper focuses on a LabVIEW platform that we have developed to enable anatomical and functional imaging with micro-CT and DSA. Our LabVIEW applications integrate and control all the elements of our system including a dual source/detector X-ray system, a mechanical ventilator, a physiological monitor, and a power microinjector for the vascular delivery of X-ray contrast agents. Various applications allow cardiac- and respiratory-gated acquisitions for both DSA and micro-CT studies. Our results illustrate the application of DSA for cardiopulmonary studies and vascular imaging of the liver and coronary arteries. We also show how DSA can be used for functional imaging of the kidney. Finally, the power of 4D micro-CT imaging using both prospective and retrospective gating is shown for cardiac imaging.

3D CT versus axial helical CT versus conventional tomography in the classification of acetabular fractures: A ROC analysis

International Nuclear Information System (INIS)

Kickuth, Ralph; Laufer, Ulf; Hartung, Guido; Gruening, Christian; Stueckle, Christoph; Kirchner, Johannes

2002-01-01

AIM: To assess the diagnostic power of three-dimensional computed tomography (3D CT), axial helical computed tomography (CT) and conventional tomography in the classification of acetabular fractures by interdisciplinary review. MATERIALS AND METHODS: Receiver operating characteristics (ROCs) were assessed for two radiologists and two surgeons blinded to the presence of acetabular fractures in an animal model (a total of 62 porcine hips, 40 of them with artificial acetabular fractures). Main target parameter was the diagnostic accuracy in the classification of the artificial fractures following Judet et al. RESULTS: ROC analysis for radiologists showed A z values of 0·83 for 3D CT, 0·81 for axial helical CT, and 0·78 for conventional tomography; differences between the three techniques were not significant (P = 0·46-0·73). A z values for the surgeons were 0·87 for 3D CT, 0·68 for axial helical CT, and 0·60 for conventional tomography; 3D CT was significantly better than axial helical CT (P = 0·01) and conventional tomography (P = 0·001). The differences between axial helical CT and conventional tomography were not significant (P = 0·37). CONCLUSION: Acetabular fractures are best classified by 3D CT, followed by axial helical CT and conventional tomography when assessed by surgeons. 3D CT did not provide any additional significant benefit in the classification performed by radiologists. Kickuth, R. et al. (2002)

Three dimensional mapping of strontium in bone by dual energy K-edge subtraction imaging

International Nuclear Information System (INIS)

Cooper, D M L; Chapman, L D; Carter, Y; Zhouping, W; Wu, Y; Panahifar, A; Duke, M J M; Doschak, M; Britz, H M; Bewer, B

2012-01-01

The bones of many terrestrial vertebrates, including humans, are continually altered through an internal process of turnover known as remodeling. This process plays a central role in bone adaptation and disease. The uptake of fluorescent tetracyclines within bone mineral is widely exploited as a means of tracking new tissue formation. While investigation of bone microarchitecture has undergone a dimensional shift from 2D to 3D in recent years, we lack a 3D equivalent to fluorescent labeling. In the current study we demonstrate the ability of synchrotron radiation dual energy K-edge subtraction (KES) imaging to map the 3D distribution of elemental strontium within rat vertebral samples. This approach has great potential for ex vivo analysis of preclinical models and human tissue samples. KES also represents a powerful tool for investigating the pharmokinetics of strontium-based drugs recently approved in many countries around the globe for the treatment of osteoporosis. (paper)

Volume-artifact reduction modality by helical CT of the anterior, middle and posterior carnial fossae. Comparison with conventional CT; Volumen-Artefakt-Reduktionstechnik mittels Spiral-CT in der vorderen, mittleren und hinteren Schaedelgrube. Vergleich mit der konventionellen kranialen CT

Energy Technology Data Exchange (ETDEWEB)

Dorenbeck, U.; Finkenzeller, T.; Hill, K.; Feuerbach, S.; Link, J. [Regensburg Univ. (Germany). Inst. fuer Roentgendiagnostik

2000-04-01

Purpose: The object of this study was to determine the extent to which a new volume-artifact reduction (VAR) modality using helical CT was able to reduce artifacts in the anterior, middle and posterior fossae in comparison with conventional CT (sequential mode). Methods: In a prospective, randomized trial, 50 patients underwent helical CT (VAR) and 50 underwent sequential CT. The results were evaluated by three radiologists; influences on image quality where scaled between 1 (no artifact) and 4 (not assessable). Eight regions of the anterior, middle and posterior fossae were evaluated. Results: On average, artifacts were scaled at 2.5 in helical CT (VAR) and 3.1 in conventional CT. Significant differences were seen at the eyeball, anterior to the petrosol bone, at the internal occipital crest, and at the level of the transverse sinus (p<0.005). Conclusions: Helical CT with the VAR modality is superior to conventional, sequential CT in the area of the anterior, middle and posterior fossae. (orig.) [German] Ziel: Das Ziel dieser Studie war herauszufinden, inwieweit ein neuer Volumen-Artefakt-Reduktionsmodus (VAR) im Spiral-CT in der vorderen, mittleren und hinteren Schaedelgrube gegenueber der Einzelschicht-CT zu einer Artefaktverringerung beitragen kann. Methoden: In einer prospektiven randomisierten Studie wurden 50 Untersuchungen mit Spiral-CT und 50 mit Einzelschicht-CT bezueglich Artefakten verglichen. Die Auswertung erfolgte durch drei Radiologen, die Bildqualitaet wurde in einer Skala zwischen 1 (kein Artefakt) und 4 (Beurteilung der Region wegen Artefakten nicht moeglich) angegeben. Acht anatomische Regionen in der vorderen, mittleren und hinteren Schaedelgrube wurden auf Beeintraechtigung durch Artefakte untersucht. Ergebnisse: Im Durchschnitt betrug die Bewertung fuer die Artefaktbeeintraechtigung beim Spiral-CT (VAR) 2,5 gegenueber 3,1 bei der Einzelschicht-CT. Der VAR-Modus ermoeglichte in der mittleren und hinteren Schaedelgrube sowie im Balbus oculi

[18F]Fluorodeoxyglucose (FDG)-Positron Emission Tomography (PET)/Computed Tomography (CT) in Suspected Recurrent Breast Cancer: A Prospective Comparative Study of Dual-Time-Point FDG-PET/CT, Contrast-Enhanced CT, and Bone Scintigraphy.

Science.gov (United States)

Hildebrandt, Malene Grubbe; Gerke, Oke; Baun, Christina; Falch, Kirsten; Hansen, Jeanette Ansholm; Farahani, Ziba Ahangarani; Petersen, Henrik; Larsen, Lisbet Brønsro; Duvnjak, Sandra; Buskevica, Inguna; Bektas, Selma; Søe, Katrine; Jylling, Anne Marie Bak; Ewertz, Marianne; Alavi, Abass; Høilund-Carlsen, Poul Flemming

2016-06-01

To prospectively investigate the diagnostic accuracy of [(18)F]fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) with dual-time-point imaging, contrast-enhanced CT (ceCT), and bone scintigraphy (BS) in patients with suspected breast cancer recurrence. One hundred women with suspected recurrence of breast cancer underwent 1-hour and 3-hour FDG-PET/CT, ceCT, and BS within approximately 10 days. The study was powered to estimate the precision of the individual imaging tests. Images were visually interpreted using a four-point assessment scale, and readers were blinded to other test results. The reference standard was biopsy along with treatment decisions and clinical follow-up (median, 17 months). FDG-PET/CT resulted in no false negatives and fewer false positives than the other imaging techniques. Accuracy of results were similar for 1-hour and 3-hour FDG-PET/CT. For distant recurrence, the area under the receiver operating curve was 0.99 (95% CI, 0.97 to 1) for FDG-PET/CT, 0.84 (95% CI, 0.73 to 0.94) for ceCT, and 0.86 (95% CI, 0.77 to 0.94) for the combined ceCT+BS. Of 100 patients, 22 (22%) were verified with distant recurrence, and 18 of these had bone involvement. Nineteen patients (19%) had local recurrence only. In exploratory analyses, diagnostic accuracy of FDG-PET/CT was better than ceCT alone or ceCT combined with BS in diagnosing distant, bone, and local recurrence, shown by a greater area under the receiver operating curve and higher sensitivity, specificity, and superior likelihood ratios. FDG-PET/CT was accurate in diagnosing recurrence in breast cancer patients. It allowed for distant recurrence to be correctly ruled out and resulted in only a small number of false-positive cases. Exploratory findings suggest that FDG-PET/CT has greater accuracy than conventional imaging technologies in this patient group. © 2016 by American Society of Clinical Oncology.

Partially Biodegradable Distraction Implant to Replace Conventional Implants in Alveolar Bone of Insufficient Height: A Preliminary Study in Dogs.

Science.gov (United States)

Li, Tao; Zhang, Yongqiang; Shao, Bo; Gao, Yuan; Zhang, Chen; Cao, Qiang; Kong, Liang

2015-12-01

Dental implants have been widely used in the last few decades. However, patients with insufficient bone height need reconstructive surgeries before implant insertion. The distraction implant (DI) has been invented to simplify the treatment procedure, but the shortcomings of DIs have limited their clinical use. We incorporated biodegradable polyester into a novel DI called the partially biodegradable distraction implant (PBDI). The purpose of this study was to assess the radiological, histological, and biomechanical properties of the PBDI in animal models. PBDIs were manufactured and inserted into the atrophied mandibles of nine dogs. Box-shaped alveolar bones were segmented and distracted. The dogs were randomly divided into three groups that were sacrificed 1, 2, and 3 months after the implant insertion. Actual augmentation height (AAH) of the bone segments was measured to evaluate the effect of distraction. X-ray examination and micro-CT reconstruction and analysis were used to evaluate the regenerated bone in the distraction gap and bone around the functional element. Histological sections were used to evaluate the osseointegration and absorption of the PBDI. Fatigue tests were used to evaluate the biomechanical properties of the PBDI. Little change was found in AAH among the three groups. X-ray examination and micro-CT reconstruction showed good growth of regenerated bone in the distraction gap. Alveolar bone volume around the functional element increased steadily. No obvious bone absorption occurred in the alveolar crest around PBDI. Three months after distraction, the functional element achieved osseointegration, and the support element began to be absorbed. All PBDIs survived the fatigue test. The PBDI is a novel and reliable dental implant. It becomes a conventional implant after the absorption of the support element and the removal of the distraction screw. It is a promising replacement for conventional implants in patients with insufficient alveolar bone

Bone quality evaluation at dental implant site using multislice CT, micro-CT, and cone beam CT

NARCIS (Netherlands)

Parsa, A.; Ibrahim, N.; Hassan, B.; van der Stelt, P.; Wismeijer, D.

2015-01-01

Objectives The first purpose of this study was to analyze the correlation between bone volume fraction (BV/TV) and calibrated radiographic bone density Hounsfield units (HU) in human jaws, derived from micro-CT and multislice computed tomography (MSCT), respectively. The second aim was to assess the

Multidetector-row CT angiography of hepatic artery: comparison with conventional angiography

International Nuclear Information System (INIS)

Kim, Jin Woong; Jeong, Yong Yeon; Yoon, Woong; Kim, Jae Kyu; Park, Jin Gyoon; Seo, Jeong Jin; Kang, Heoung Keun

2003-01-01

To determine the usefulness of three-dimensional CT angiography using multidetector-row CT (MD-CT) for delineating the arterial anatomy of the liver. Hepatic arterial three-dimensional CT angiography was performed using MDCT (lightspeed Qx/I; GE medical systems, milwaukee, Wis., U.S.A.) in 45 patients with HCC undergoing conventional angiography for transcatheter hepatic arterial chemoembolization. The scanning parameters during the early arterial phase were 2.5 mm slice thickness, 7.5 mm rotation of table speed, and a pitch of 3. Images were obtained by one radiologist using maximum intensity projection from axial CT images obtained during the early arterial phase. Two radiologists blinded to the findings of conventional angiography independently evaluated the hepatic arterial anatomy and the quality of the images obtained. Compared with conventional angiography, reader A correctly evaluated the hepatic arterial anatomy depicted at three-dimensional CT angiography. Reader B's evaluation was correct in 40 of 45 patients. Interobserver agreement was good (kappa value, 0.73), and both readers assessed the quality of three-dimensional CT angiography as excellent. Three-dimensional CT angiography using MDCT was accurate for delineating the arterial anatomy of the liver, and interobserver agreement was good. The modality may provide, prior to conventional angiography, valuable information regrading a patient's hepatic arterial anatomy

[Quantitative image of bone mineral content--dual energy subtraction in a single exposure].

Science.gov (United States)

Katoh, T

1990-09-25

A dual energy subtraction system was constructed on an experimental basis for the quantitative image of bone mineral content. The system consists of a radiography system and an image processor. Two radiograms were taken with dual x-ray energy in a single exposure using an x-ray beam dichromized by a tin filter. In this system, a film cassette was used where a low speed film-screen system, a copper filter and a high speed film-screen system were layered on top of each other. The images were read by a microdensitometer and processed by a personal computer. The image processing included the corrections of the film characteristics and heterogeneity in the x-ray field, and the dual energy subtraction in which the effect of the high energy component of the dichromized beam on the tube side image was corrected. In order to determine the accuracy of the system, experiments using wedge phantoms made of mixtures of epoxy resin and bone mineral-equivalent materials in various fractions were performed for various tube potentials and film processing conditions. The results indicated that the relative precision of the system was within +/- 4% and that the propagation of the film noise was within +/- 11 mg/cm2 for the 0.2 mm pixels. The results also indicated that the system response was independent of the tube potential and the film processing condition. The bone mineral weight in each phalanx of the freshly dissected hand of a rhesus monkey was measured by this system and compared with the ash weight. The results showed an error of +/- 10%, slightly larger than that of phantom experiments, which is probably due to the effect of fat and the variation of focus-object distance. The air kerma in free air at the object was approximately 0.5 mGy for one exposure. The results indicate that this system is applicable to clinical use and provides useful information for evaluating a time-course of localized bone disease.

Comparison of conventional panoramic radiography and panoramic digital subtraction radiography in detection of simulated lesions of mandibular condyle

Directory of Open Access Journals (Sweden)

Panjnoush M.

2008-12-01

Full Text Available "n  "nBackground and Aim: Digital subtraction Radiography (DSR is a method of accurate assessing condylar head changes. several studies have been carried out in applying DSR in dentistry, however there is a few number of studies in efficacy of DSR method in assesment of condylar head changes, The aim of this study was to compare panoramic radiography and DSR detecting simulated lesions of the mandibular condyl. "nMaterials and Methods: this was a process reaserch study, in which two dry human skulls with no obvious temporomandibular joint pathology were used. Osteophytic lesions were simulated using three sizes of bone chips that were placed on the medial portion of anterior and superolateral aspects of the condyle. Osteolytic lesions were simulated making 1 and 2 mm holes using round burr in the central portion of anterior aspect and Lateral pole of the condyle. Panoramic radiographs were prepared with and without the lesions in place. These paired radiographs were digitized and digital- subtraction images of the original panoramic images were obtained. Eight observers evaluated 155 images of each modality for the presence or absence and the type of simulated lesions of the mandibular condyle. Sensitivity, specificity, reliability and measure of agreement were analyzed using kappa test and crossed tables and qualitative variables were assess by chi-square and fisher's Exact test. "nResults: Specificity of panoramic and DSR methods were 15.4% and 66.7% respectively. Sensitivity of panoramic and DSR methods were 61.1% and 80.6% for osteophytic lesions and 37.5% and 83.3% for Osteolytic lesions. The percentage of correct decisions made in DSR method was significantly more than conventional panoramic method (82.6% vs 41.9% (p<0.0001. "nConclusion: Based on the results of this study digital subtraction technique was significantly more accurate than the panoramic radiographs in detection of simulated lesions of the mandibular condyle.

Clinical value of SPECT/CT imaging in the diagnosis of bone metastasis

International Nuclear Information System (INIS)

Wang Xinhua; Zhao Yanping; Lu Haijian; Dong Zhanfei

2010-01-01

Objective: To evaluate the clinical value of 99 Tc m -methylene diphosphonic acid (MDP) SPECT/CT imaging for the diagnosis of bone metastasis. Methods: Patients suspected for bone metastasis and with bone pain of unknown origin were included in this study (n=237). All cases underwent SPECT and CT imaging at 180 min after 99 Tc m -MDP injection. Diagnosis was confirmed by pathology (n=21), more than 2 kinds of radiologieal imaging (MRI, CT, X-ray) (n=106), and clinical follow up in 2 years (n=110). χ 2 -test was used to compare the results of planar and SPECT/CT imaging using SAS 6.12 software. Results: In 237 patients, planar imaging of 142 cases matched the final diagnosis in which 72 had benign lesions and 70 had bone metastases. The definite coincidence rate was 95.30% (142/149). SPECT/CT imaging of 224 cases matched the final diagnosis in which 104 had benign lesions and 120 cases diagnosed as bone metastases. The coincidence and definite coincidence rates were 94.51% (224/237), and 99.48% (192/193). Difference in the definite coincidence rate between planar and SPECT/CT imaging was statistically significant (χ 2 = 5.37, P=0.024). Conclusion: SPECT/CT imaging is valuable for accurate localization of osseous pathology and for improvement of diagnosing bone metastasis. (authors)

Effective radiation dose from semicoronal CT of the sacroiliac joints in comparison with axial CT and conventional radiography

Energy Technology Data Exchange (ETDEWEB)

Jurik, Anne Grethe; Boecker Puhakka, Katriina [Department of Radiology R, Aarhus University Hospital, Aarhus Kommunehospital, Noerrebrogade 44, 8000 Aarhus C (Denmark); Hansen, Jolanta [Department of Medical Physics, Aarhus University Hospital, Aarhus Kommunehospital, Noerrebrogade 44, 8000 Aarhus C (Denmark)

2002-11-01

The aim of this study was to evaluate the radiation dose given by semicoronal CT of the sacroiliac joints (SIJs) in comparison with axial CT and conventional radiography. The total effective radiation doses given by serial contiguous semicoronal and axial CT, using 5-mm slices, 120 kV and 330 mAs, were determined by measurement of organ doses using an anthropomorphic Rando Alderson phantom paced with thermoluminescence dosimeters. The doses given by conventional antero-posterior (AP) and oblique projections of the SIJs were determined similarly. In a female the total effective dose by semicoronal CT was found to be more than six times lower than by axial CT and 2.5 times lower than the dose use to obtain a conventional AP radiograph, the values being 102, 678, and 255 {mu}Sv, respectively. The effective dose by semicoronal CT was only a little higher than the dose given to obtain two oblique radiographs. In a male with lead protection of the gonads the dose by semicoronal CT was four times lower than by axial CT, but higher than by conventional radiography. In conclusion, the effective dose by semicoronal CT of the SIJs is lower than by axial CT, and in females a semicoronal CT implies a lower effective radiation dose that used to obtain an AP radiograph. (orig.)

Digital subtraction angiography in head and neck radiology

Energy Technology Data Exchange (ETDEWEB)

Carmody, R F; Seeger, J F; Smith, R L; Horsley, W W; Miller, R W

1984-07-01

Intravenous digital subtraction angiography (IVDSA) was used to evaluate 44 patients with suspected otolaryngologic abnormalities. Sixteen had IVDSA for pulsatile tinnitus or suspected glomus tumor of the petrous bone. Nine patients were evaluated because of pulsatile neck masses, and 12 others had suspected tumors of the neck, face, and paranasal sinuses. Seven had IVDSA following head and neck trauma. The technique of examination is described. The current indications of IVDSA in head and neck radiology are discussed. It is concluded that IVDSA is a suitable substitute for conventional angiography for many otolaryngologic conditions and, because of its safety, can be used more liberally.

Synchrotron radiation μCT and histology evaluation of bone-to-implant contact.

Science.gov (United States)

Neldam, Camilla Albeck; Sporring, Jon; Rack, Alexander; Lauridsen, Torsten; Hauge, Ellen-Margrethe; Jørgensen, Henrik L; Jørgensen, Niklas Rye; Feidenhansl, Robert; Pinholt, Else Marie

2017-09-01

The purpose of this study was to evaluate bone-to-implant contact (BIC) in two-dimensional (2D) histology compared to high-resolution three-dimensional (3D) synchrotron radiation micro computed tomography (SR micro-CT). High spatial resolution, excellent signal-to-noise ratio, and contrast establish SR micro-CT as the leading imaging modality for hard X-ray microtomography. Using SR micro-CT at voxel size 5 μm in an experimental goat mandible model, no statistically significant difference was found between the different treatment modalities nor between recipient and reconstructed bone. The histological evaluation showed a statistically significant difference between BIC in reconstructed and recipient bone (p micro-CT evaluation a bias of 5.2% was found in reconstructed area, and 15.3% in recipient bone. We conclude that for evaluation of BIC with histology and SR micro-CT, SR micro-CT cannot be proven more precise than histology for evaluation of BIC, however, with this SR micro-CT method, one histologic bone section is comparable to the 3D evaluation. Further, the two methods complement each other with knowledge on BIC in 2D and 3D. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Micro-CT analyses of historical bone samples presenting with osteomyelitis

Energy Technology Data Exchange (ETDEWEB)

Lamm, C.; Pietschmann, P. [Medical University Vienna (MUV), Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Vienna (Austria); Dockner, M.; Weber, G.W. [University of Vienna, Department of Anthropology, Vienna (Austria); University of Vienna, Core Facility for Micro-Computed Tomography, Vienna (Austria); Pospischek, B.; Winter, E.; Patzak, B. [Museum of Natural History (NHM), Collection of Anatomical Pathology in the Madhouse Tower, Vienna (Austria); Pretterklieber, M. [Medical University of Vienna (MUV), Department of Applied Anatomy, Vienna (Austria)

2015-10-15

Osteomyelitis is an inflammation of the bone marrow mainly caused by bacteria such as Staphylococcus aureus. It typically affects long bones, e.g. femora, tibiae and humeri. Recently micro-computed tomography (μCT) techniques offer the opportunity to investigate bone micro-architecture in great detail. Since there is no information on long bone microstructure in osteomyelitis, we studied historic bone samples with osteomyelitis by μCT. We investigated 23 femora of 22 individuals suffering from osteomyelitis provided by the Collection of Anatomical Pathology, Museum of Natural History, Vienna (average age 44 ±19 years); 9 femora from body donors made available by the Department of Applied Anatomy, Medical University of Vienna (age range, 56-102 years) were studied as controls. Bone microstructure was assessed by μCT VISCOM X 8060 II with a minimal resolution of 18 μm. In the osteomyelitic femora, most prominent alterations were seen in the cortical compartment. In 71.4 % of the individuals with osteomyelitis, cortical porosity occurred. 57.1 % of the individuals showed cortical thinning. In 42.9 % trabecularisation of cortical bone was observed. Osteomyelitis is associated with severe alterations of cortical bone structure otherwise typically observed at old age such as cortical porosity and cortical thinning. (orig.)

Computed Tomography (CT) -- Head

Medline Plus

Full Text Available ... its ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional x-rays, CT scanning provides very detailed images of many types of tissue as well as the lungs, bones, ...

Computed Tomography (CT) -- Sinuses

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Full Text Available ... its ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional x-rays, CT scanning provides very detailed images of many types of tissue as well as the lungs, bones, ...

Abdominal and Pelvic CT

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Full Text Available ... its ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional x-rays, CT scanning provides very detailed images of many types of tissue as well as the lungs, bones, ...

Appearance and impact of post-operative intracranial clips and coils on whole-brain CT angiography and perfusion

International Nuclear Information System (INIS)

Roach, Cayce J.; Russell, Cheryl L.; Hanson, Eric H.; Bluett, Brent; Orrison, William W.

2012-01-01

Background: To evaluate the effect of vascular clips and endovascular coils placed for intracranial aneurysms and arteriovenous malformations on whole-brain computed tomography (CT) angiography and perfusion. Methods: A 320-detector row dynamic volume CT system imaged 11 patients following surgical placement of vascular clips or endovascular coils. The extent of clip and coil subtraction by automated software was evaluated using CT digital subtraction angiography and CT perfusion. Impact on CT perfusion values by retained intracranial devices was compared to age- and gender-matched controls. Results: Clip and coil subtraction on CT angiography was graded as good in 8 and moderate in 3 cases. A residual neck and additional aneurysm were noted in 1 of 11 patients. Post-procedural axial slice level CT perfusion values decreased in reliability with increasing proximity to the metallic devices secondary to beam hardening. However, the intracranial devices did not affect axial slice level CTP values of cerebral blood volume, cerebral blood flow and mean transit time outside of the level of the device. Time to peak values was globally decreased outside of the immediate vascular intervention region. Conclusions: Advances in CT technology have provided clinically useful subtraction of intracranial clips and coils. While CT perfusion values were altered in device subtraction areas and within beam hardening artifact areas; they can provide valuable postoperative information on whole-brain hemodynamics. In selected cases, the combination of CT angiography and whole-brain CT perfusion can offer an alternative to conventional angiography that is a more invasive option.

The oblique occipital sinus: anatomical study using bone subtraction 3D CT venography.

Science.gov (United States)

Shin, Hwa Seon; Choi, Dae Seob; Baek, Hye Jin; Choi, Ho Cheol; Choi, Hye Young; Park, Mi Jung; Kim, Ji Eun; Han, Jeong Yeol; Park, SungEun

2017-06-01

An occipital sinus draining into the sigmoid sinus has been termed the oblique occipital sinus (OOS). The frequency, anatomical features, patterns, and relationship with the transverse sinus of the oblique occipital sinus were analyzed in this study. The study included 1805 patients who underwent brain CT angiography during a 3-year period from 2013 to 2015. CT examinations were performed using a 64-slice MDCT system. The OOS was identified in 41 patients (2.3%). There were many anatomical variations in the oblique occipital sinuses. A hypoplastic or aplastic TS was seen in 31 (75.6%) of the 41 patients with OOS. Many anatomical variations in the oblique occipital sinus can be seen on CT venography. Some OOSs function as the main drainage route of the intracranial veins instead of the TS. Thus, careful examination is essential for preoperative evaluation in posterior fossa lesions.

Detectability index of differential phase contrast CT compared with conventional CT: a preliminary channelized Hotelling observer study

Science.gov (United States)

Tang, Xiangyang; Yang, Yi; Tang, Shaojie

2013-03-01

Under the framework of model observer with signal and background exactly known (SKE/BKE), we investigate the detectability of differential phase contrast CT compared with that of the conventional attenuation-based CT. Using the channelized Hotelling observer and the radially symmetric difference-of-Gaussians channel template , we investigate the detectability index and its variation over the dimension of object and detector cells. The preliminary data show that the differential phase contrast CT outperforms the conventional attenuation-based CT significantly in the detectability index while both the object to be detected and the cell of detector used for data acquisition are relatively small. However, the differential phase contrast CT's dominance in the detectability index diminishes with increasing dimension of either object or detector cell, and virtually disappears while the dimension of object or detector cell approaches a threshold, respectively. It is hoped that the preliminary data reported in this paper may provide insightful understanding of the differential phase contrast CT's characteristic in the detectability index and its comparison with that of the conventional attenuation-based CT.

SU-D-17A-02: Four-Dimensional CBCT Using Conventional CBCT Dataset and Iterative Subtraction Algorithm of a Lung Patient

International Nuclear Information System (INIS)

Hu, E; Lasio, G; Yi, B

2014-01-01

Purpose: The Iterative Subtraction Algorithm (ISA) method generates retrospectively a pre-selected motion phase cone-beam CT image from the full motion cone-beam CT acquired at standard rotation speed. This work evaluates ISA method with real lung patient data. Methods: The goal of the ISA algorithm is to extract motion and no- motion components form the full reconstruction CBCT. The workflow consists of subtracting from the full CBCT all of the undesired motion phases and obtain a motion de-blurred single-phase CBCT image, followed by iteration of this subtraction process. ISA is realized as follows: 1) The projections are sorted to various phases, and from all phases, a full reconstruction is performed to generate an image CTM. 2) Generate forward projections of CTM at the desired phase projection angles, the subtraction of projection and the forward projection will reconstruct a CTSub1, which diminishes the desired phase component. 3) By adding back the CTSub1 to CTm, no motion CBCT, CTS1, can be computed. 4) CTS1 still contains residual motion component. 5) This residual motion component can be further reduced by iteration.The ISA 4DCBCT technique was implemented using Varian Trilogy accelerator OBI system. To evaluate the method, a lung patient CBCT dataset was used. The reconstruction algorithm is FDK. Results: The single phase CBCT reconstruction generated via ISA successfully isolates the desired motion phase from the full motion CBCT, effectively reducing motion blur. It also shows improved image quality, with reduced streak artifacts with respect to the reconstructions from unprocessed phase-sorted projections only. Conclusion: A CBCT motion de-blurring algorithm, ISA, has been developed and evaluated with lung patient data. The algorithm allows improved visualization of a single phase motion extracted from a standard CBCT dataset. This study has been supported by National Institute of Health through R01CA133539

X-ray CT high-density artefact suppression in the presence of bones

Energy Technology Data Exchange (ETDEWEB)

Wei Jikun [School of Health Sciences, 550 Stadium Mall Drive, West Lafayette, IN 47907-2051 (United States); Chen Laigao [BioImaging Center of Emphasis, Pfizer Global Research and Development, 2800 Plymouth RD, Ann Arbor, MI 48105 (United States); Sandison, George A [School of Health Sciences, 550 Stadium Mall Drive, West Lafayette, IN 47907-2051 (United States); Liang Yun [Department of Radiology, Indiana University Medical School, Indianapolis, IN 46202 (United States); Xu, Lisa X [School of Mechanical Engineering, 585 Purdue Mall, West Lafayette, IN 47907-2040 (United States)

2004-12-21

This paper presents a novel method of reducing x-ray CT high-density artefacts generated by metal objects when abundant bone structures are present in the region of interest. This method has an advantage over previously proposed methods since it heavily suppresses the metal artefacts without introducing extra bone artefacts. The method of suppression requires that bone pixels are isolated and segmented by thresholding. Then artificial CT numbers are assigned to the bone pixels so that their projection profiles are smooth and thus can be properly simulated by a polynomial interpolation. The projection profile of the metal object is then removed to fully suppress the artefacts. The resulting processed profile is fed to a reconstruction routine and the previously preserved bone pixels added back. The new method utilizes two important features of the CT image with metal artefacts: (a) metal and bone pixels are not severely affected by the high-density artefacts and (b) the high-density artefacts can be located in specific projection channels in the profile domain, although they are spread out in the image domain. This suppression method solves the problem of CT image artefacts arising from metal objects in the body. It has the potential to greatly improve diagnostic CT imaging in the presence of these objects and treatment planning that utilizes CT for patients with metal applicators (e.g., brachytherapy for cervix cancer and prostate cryotherapy)

X-ray CT high-density artefact suppression in the presence of bones

International Nuclear Information System (INIS)

Wei Jikun; Chen Laigao; Sandison, George A; Liang Yun; Xu, Lisa X

2004-01-01

This paper presents a novel method of reducing x-ray CT high-density artefacts generated by metal objects when abundant bone structures are present in the region of interest. This method has an advantage over previously proposed methods since it heavily suppresses the metal artefacts without introducing extra bone artefacts. The method of suppression requires that bone pixels are isolated and segmented by thresholding. Then artificial CT numbers are assigned to the bone pixels so that their projection profiles are smooth and thus can be properly simulated by a polynomial interpolation. The projection profile of the metal object is then removed to fully suppress the artefacts. The resulting processed profile is fed to a reconstruction routine and the previously preserved bone pixels added back. The new method utilizes two important features of the CT image with metal artefacts: (a) metal and bone pixels are not severely affected by the high-density artefacts and (b) the high-density artefacts can be located in specific projection channels in the profile domain, although they are spread out in the image domain. This suppression method solves the problem of CT image artefacts arising from metal objects in the body. It has the potential to greatly improve diagnostic CT imaging in the presence of these objects and treatment planning that utilizes CT for patients with metal applicators (e.g., brachytherapy for cervix cancer and prostate cryotherapy)

Synchrotron radiation μCT and histology evaluation of bone-to-implant contact

DEFF Research Database (Denmark)

Neldam, Camilla Albeck; Sporring, Jon; Rack, Alexander

2017-01-01

The purpose of this study was to evaluate bone-to-implant contact (BIC) in two-dimensional (2D) histology compared to high-resolution three-dimensional (3D) synchrotron radiation micro computed tomography (SR micro-CT). High spatial resolution, excellent signal-to-noise ratio, and contrast...... establish SR micro-CT as the leading imaging modality for hard X-ray microtomography. Using SR micro-CT at voxel size 5 μm in an experimental goat mandible model, no statistically significant difference was found between the different treatment modalities nor between recipient and reconstructed bone....... Comparing histology and SR micro-CT evaluation a bias of 5.2% was found in reconstructed area, and 15.3% in recipient bone. We conclude that for evaluation of BIC with histology and SR micro-CT, SR micro-CT cannot be proven more precise than histology for evaluation of BIC, however, with this SR micro-CT...

The role of bone SPECT/CT in the evaluation of lumbar spinal fusion with metallic fixation devices

DEFF Research Database (Denmark)

Damgaard, Morten; Nimb, Lars; Madsen, Jan L

2010-01-01

PURPOSE: It is difficult to evaluate the stability of the lumbar spondylodesis with metallic fixation devices by conventional imaging methods such as radiography or magnetic resonance imaging. It is unknown whether single photon emission computed tomography/computed tomography (SPECT/CT) may......, whereas in 1 case loose pedicle screws were detected at a wrong vertebral level. CONCLUSION: SPECT/CT may be useful to detect a lack of fixation of the metallic implants, and hence instability of the spondylodesis by evaluating the focal bone mineralization activity in relation to the pedicle screws....

Growing bone assessment made easy at chairside

Directory of Open Access Journals (Sweden)

Priyanka Dalvi

2016-01-01

Full Text Available Various intraoral radiographic techniques have been utilized to study bone changes following periodontal therapy, for example, digital subtraction radiography, computer-assisted densitometric image analysis, computed tomography (CT, and cone bean CT. This short communication provides an insight about a novel yet simple technique which utilizes a user-friendly software (Adobe Photoshop CS3 and provides the clinician a quick, objective economical tool to assess periodontal regeneration (bone fill radiographically. The use of this software is recommended in any clinical trial, wherein bone is target tissue to be assessed at different time intervals. It can find clinical applications include endodontic periapical cyst therapy, implant, oral and maxillofacial surgery, and orthopedics surgeries. This method is simple, reliable, and reproducible and helps in objective assessment of radiographic changes of the periodontal osseous defects following periodontal therapy.

Bone Mechanical Strength Estimation from Micro X-ray CT Image

National Research Council Canada - National Science Library

Matani, A

2001-01-01

... (Bone Mineral Density), an index to evaluate the mechanical strength of the bone, does not always reflect the strength, On the other hand, micro X-ray CT has revealed the inner structure of bone, Under such circumstances...

Detection of bone metastases in breast cancer patients in the PET/CT era: Do we still need the bone scan?

Science.gov (United States)

Caglar, M; Kupik, O; Karabulut, E; Høilund-Carlsen, P F

2016-01-01

To examine the value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) for the detection of bone metastasis in breast cancer patients and assess whether whole body bone scan (BS) with (99m)Tc-methylene diphosphonate provides any additional information. Study group comprised 150 patients, mean age 52 years (range 27-85) with breast cancer, suspected of having bone metastases. All patients had undergone both FDG-PET/CT and BS with or without single photon emission tomography/computed tomography (SPECT/CT) within a period of 6 weeks. The final diagnosis of bone metastasis was established by histopathological findings, additional imaging, or clinical follow-up longer than 10 months. Cancer antigen 15-3 (CA15-3) and carcinoembryogenic antigen (CEA) were measured in all patients. Histologically 83%, 7% and 10% had infiltrating ductal, lobular and mixed carcinoma respectively. Confirmed bone metastases were present in 86 patients (57.3%) and absent in 64 (42.7%). Mean CA15-3 and CEA values in patients with bone metastases were 74.6ng/mL and 60.4U/mL respectively, compared to 21.3ng/mL and 3.2U/mL without metastases (p<0.001). The sensitivity of FDG-PET/CT for the detection of bone metastases was 97.6% compared to 89.5% with SPECT/CT. In 57 patients, FDG-PET/CT correctly identified additional pulmonary, hepatic, nodal and other soft tissue metastases, not detected by BS. Our findings suggest that FDG-PET/CT is superior to BS with or without SPECT/CT. Copyright © 2015 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

Detection of lung nodules with low-dose spiral CT: comparison with conventional dose CT

International Nuclear Information System (INIS)

Zhu Tianzhao; Tang Guangjian; Jiang Xuexiang

2004-01-01

Objective: To investigate the effect of reducing scan dose on the lung nodules detection rate by scanning a lung nodule model at low dose and conventional dose. Methods: The lung and the thoracic cage were simulated by using a cyst filled with water surrounded by a roll bandage. Flour, butter, and paraffin wax were mixed together by a certain ratio to simulate lung nodules of 10 mm and 5 mm in diameter with the CT values ranging from -10 to 50 HU. Conventional-dose scan (240 mA, 140 kV) and low-dose scan of three different levels (43 mA, 140 kV; 50 mA, 120 kV; 75 mA, 80 kV) together with three different pitches (1.0, 1.5, and 2.0) were performed. The images of the simulated nodules were combined with the CT images of a normal adult's upper, middle, and inferior lung. Three radiologists read the images and the number of the nodules they detected including both the real ones and the false-positive ones was calculated to investigate weather there was any difference among different doses, pitch groups, and different locations. Results: The detection rate of the 10 mm and 5 mm nodules was 100% and 89.6% respectively by the low-dose scan. There was no difference between low-dose and conventional-dose CT (χ 2 =0.6907, P>0.70). The detection rate of 5 mm nodules declined when large pitch was used. Conclusion: The detection rates of 10 mm and 5 mm nodules had no difference between low-dose CT and conventional-dose CT. As the pitch augmented, the detection rate for the nodules declined

Incidental internal carotid artery calcifications on temporal bone CT in children

International Nuclear Information System (INIS)

Koch, Bernadette; Jones, Blaise; Blackham, Aaron

2007-01-01

Incidental internal carotid artery (ICA) calcifications are occasionally noted on CT images of the brain and temporal bone. In adults, incidental calcifications have been correlated with increased incidence of hypercholesterolemia, cardiac disease, diabetes and carotid stenosis. To determine the incidence of incidental calcifications of the carotid siphon on temporal bone CT in children. We retrospectively reviewed 24 months of consecutive temporal bone CT examinations in children aged 18 years and younger. CT examinations on 663 patients were reviewed and the presence or absence of ICA calcifications was ranked as absent, questionable or definitive. In patients in whom definitive calcifications were identified, hospital charts were reviewed for evidence of diabetes mellitus, hypercholesterolemia, hypertriglyceridemia, hyperlipidemia and chronic renal disease as potential causes of early atherosclerosis. Of the 663 patients, 25% had definitive calcifications within the wall of the ICA: 6% of children younger than 2 years and 28% of children 12-19 years of age. Incidentally noted ICA calcifications are a common finding on temporal bone CT in children, most likely a physiologic response to turbulent flow at natural bends in the artery rather than secondary to underlying disease predisposing to early atherosclerotic calcification. (orig.)

Incidental internal carotid artery calcifications on temporal bone CT in children

Energy Technology Data Exchange (ETDEWEB)

Koch, Bernadette; Jones, Blaise [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Blackham, Aaron [University of Cincinnati College of Medicine, Cincinnati, OH (United States)

2007-02-15

Incidental internal carotid artery (ICA) calcifications are occasionally noted on CT images of the brain and temporal bone. In adults, incidental calcifications have been correlated with increased incidence of hypercholesterolemia, cardiac disease, diabetes and carotid stenosis. To determine the incidence of incidental calcifications of the carotid siphon on temporal bone CT in children. We retrospectively reviewed 24 months of consecutive temporal bone CT examinations in children aged 18 years and younger. CT examinations on 663 patients were reviewed and the presence or absence of ICA calcifications was ranked as absent, questionable or definitive. In patients in whom definitive calcifications were identified, hospital charts were reviewed for evidence of diabetes mellitus, hypercholesterolemia, hypertriglyceridemia, hyperlipidemia and chronic renal disease as potential causes of early atherosclerosis. Of the 663 patients, 25% had definitive calcifications within the wall of the ICA: 6% of children younger than 2 years and 28% of children 12-19 years of age. Incidentally noted ICA calcifications are a common finding on temporal bone CT in children, most likely a physiologic response to turbulent flow at natural bends in the artery rather than secondary to underlying disease predisposing to early atherosclerotic calcification. (orig.)

Study of bony trabecular characteristics using bone morphometry and micro-CT

International Nuclear Information System (INIS)

Song, Young Han; Lee, Wan; Lee, Chang Jin; Ji, Jung Hyun; Lee, Byung Do

2007-01-01

The research was done to investigate the effectiveness of 2D bony morphometry and microstructure of micro-computed tomography (micro-CT) on the osteoporotic bony change. We performed the bone morphometric analysis of proximal femur in ovariectomized rabbits with BMD and micro-CT examination. Twenty-one female (Newzeland, about 16 weeks old, 2.9-3.4 kg) rabbits were used. Three rabbits were sacrificed on the day when experiment began (Basline). The remaining 18 rabbits were divided into two groups. One group was ovariectomized bilaterally (OVX) and the other animals were subjected to sham operation (Sham). Bone specimens were obtained from the right and left femur of sacrificed rabbits. At intervals of 1,2,3,5,6 months respectively, BMD tests were performed on the proximal on the proximal femur by using PIXImus 2 (GE Lunar Co. USA), 2-dimensional bone morphometric analysis by custom computer program and 2D / 3D bone structure analysis by micro-CT (Skyscan1072, Antwerpen, Belgium). Statistical analysis was carried out for the correlation between bone morphometry, micro-CT and BMD. BV/TV, Tb.Th, Tb.N of micro-CT parameters showed higher values in sham group than OVX group. N.Nd/Ar.RI, N.NdNd, N.NdTm, N. TmTm, PmB/Ar.RI, 3-D BoxSlope of 2D morphometric parameters showed higher values in Sham group than OVX group. The micro-CT parameters of Tb.Sp. Tb.N were statistically significant correlated with BMD respectively. Several 2D morphometric parameters were statistically significant correlated with BMD respectively. Several parameters of 2D bony morphometry and micro-CT showed effective aspects on the osteoporotic bony change

Dual energy CT intracranial angiography: image quality, radiation dose and initial application results

International Nuclear Information System (INIS)

Chai Xue; Zhang Longjiang; Lu Guangming; Zhou Changsheng

2009-01-01

Objective: To assess the clinical value of dual-energy intracranial CT angiography (CTA). Methods: Forty-one patients suspected of intracranial vascular diseases underwent dual-energy intracranial CT angiography, and 41 patients who underwent conventional subtraction CT were enrolled as the control group. Image quality of intracranial and skull base vessels and radiation dose between dual-energy CTA and conventional subtraction CTA were compared using two independent sample nonparametric test and independent-samples t test, respectively. Prevalence and size of lesions detected by dual-energy CTA and digital subtraction CTA were compared using paired-samples t test and Spearman correlative analysis. Results: The percentage of image quality scored 5 was 70.7% (29/41) for dual-energy CTA and 75.6% (31/41) for conventional subtraction CTA. There was no significant difference between the two groups (Z= -0.455, P=0.650). Image quality of vessels at the skull base in conventional subtraction CTA was superior to that in dual-energy CTA, especially for the petrosal and syphon segment (Z=-4.087, P=0.000). Radiation exposure of dual energy CTA and conventional CTA were (396.54±17.43) and (1090.95±114.29) mGy·cm respectively. Radiation exposure was decreased by 64% (t=-38.52, P=0.000) by dual energy CTA compared with conventional subtraction CTA. Out of the 41 patients, 19 patients were diagnosed as intracranial aneurysm, 2 patients as arteriovenous malformation (AVM), 3 patients with Moya-moya's disease, and the remaining 17 patients with negative results. Nine patients with intracranial aneurysm, 2 patients with AVM, 3 patients with Moya-moya's disease, and 2 patients with negative findings underwent DSA or operation, with concordant findings from both techniques. Diameter of aneurysm neck, long axis and minor axis by dual-energy CTA was (2.90±1.61), (5.23±1.68) and (3.83±1.69) mm, respectively; Diameter of aneurysm neck, long axis and minor axis by DSA was (2.95±1

Digital subtraction angiography in head and neck radiology

International Nuclear Information System (INIS)

Carmody, R.F.; Seeger, J.F.; Smith, R.L.; Horsley, W.W.; Miller, R.W.

1984-01-01

Intravenous digital subtraction angiography (IVDSA) was used to evaluate 44 patients with suspected otolaryngologic abnormalities. Sixteen had IVDSA for pulsatile tinnitus or suspected glomus tumor of the petrous bone. Nine patients were evaluated because of pulsatile neck masses, and 12 others had suspected tumors of the neck, face, and paranasal sinuses. Seven had IVDSA following head and neck trauma. The technique of examination is described. The current indications of IVDSA in head and neck radiology are discussed. It is concluded that IVDSA is a suitable substitute for conventional angiography for many otolaryngologic conditions and, because of its safety, can be used more liberally. (orig.)

Children's (Pediatric) CT (Computed Tomography)

Medline Plus

Full Text Available ... its ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional x-rays, CT scanning provides very detailed images of many types of tissue as well as the lungs, bones, ...

CT of osteomyelitis of the spine

International Nuclear Information System (INIS)

Golimbu, C.; Firooznia, H.; Rafii, M.

1984-01-01

Computed tomography (CT) scans were performed in 17 adults with osteomyelitis of the spine. The dominant features were paravertebral soft-tissue swelling, abscess formation, and bone erosion. In two patients there were no findings indicative of osteomyelitis on conventional radiographs, but CT revealed paravertebral abscesses and bone lysis, helping to establish the diagnosis of osteomyelitis, chiefly because of its ability to detect early erosion of spongy vertabral bone, disk involvement, paravertebral soft-tissue swelling or abscess, and extension of the pathology into the spinal canal. Furthermore, CT facilitated closed-needle biopsy, helping to establish the pathologic diagnosis

Usefulness of 18F fluoride PET/CT in breast cancer patients with osteosclerotic bone metastases

International Nuclear Information System (INIS)

Yoon, Seok Ho; Kim, Ku Sang; Kang, Seok Yun; Song, Hee Sung; Jo, Kyung Sook; Lee, Su Jin; Yoon, Joon Kee; An, Young Sil; Choi, Bong Hoi

2012-01-01

Bone metastasis is an important factor for the treatment and prognosis of breast cancer patients. Whole body bone scintigraphy (WBBS) can evaluate skeletal metastases, and 18 F FDG PET/CT seems to exhibit high specificity and accuracy in detecting bone metastases. However, there is a limitation of 18 F FDG PET in assessing sclerotic bone metastases because some lesions may be undetectable. Recent studies showed that 18 F fluoride PET/CT is more sensitive than WBBS in detecting bone metastases. This study aims to evaluate the usefulness of 18 F fluoride PET/CT by comparing it with WBBS and 18 F FDG PET/CT in breast cancer patients with osteosclerotic skeletal metastases. Nine breast cancer patients with suspected bone metastases (9 females; mean age ± SD, 55.6±10.0 years) underwent 99m Tc MDP WBBS, 18 F FDG PET/CT and 18 F fluoride PET/CT. Lesion based analysis of five regions of the skeletons(skull, vertebral column, thoracic cage, pelvic bones and long bones of extremities) and patient based analysis were performed. 18 F fluoride PET/CT, 18 F FDG PET/CT and WBBS detected 49, 20 and 25 true metastases, respectively. Sensitivity, specificity, positive predictive value and negative predictive value of 18 F fluoride PET/CT were 94.2%, 46.3%, 57.7% and 91.2%, respectively. Most true metastatic lesions of 18 F fluoride PET/CT had osteosclerotic change (45/49, 91.8%), and only four lesions showed osteolytic change. Most lesions on 18 F FDG PET/CT also demonstrated osteosclerotic change (17/20, 85.0%) with three osteolytic lesions. All true metastatic lesions detected on WBBS and 18 F FDG PET/CT were identified on 18 F fluoride PET/CT. 18 F FDG PET/CT in detecting osteosclerotic metastatic lesions. 18 F fluoride PET/CT might be useful in evaluating osteosclerotic metastases in breast cancer patients

{sup 68}Ga-DOTATATE PET/CT in recurrent medullary thyroid carcinoma: a lesion-by-lesion comparison with {sup 111}In-octreotide SPECT/CT and conventional imaging

Energy Technology Data Exchange (ETDEWEB)

Yamaga, Lilian Yuri Itaya; Cunha, Marcelo L.; Campos Neto, Guilherme C.; Garcia, Marcio R.T.; Wagner, Jairo; Funari, Marcelo B.G. [Hospital Israelita Albert Einstein, Imaging Department, Sao Paulo (Brazil); Yang, Ji H.; Camacho, Cleber P. [Universidade Federal de Sao Paulo, Multiple Neoplasia Outpatiet Clinic, Sao Paulo (Brazil)

2017-09-15

The aim of this study was to prospectively compare the detection rate of {sup 68}Ga-DOTATATE PET-CT with {sup 111}In-octreotide SPECT-CT and conventional imaging (CI) in medullary thyroid carcinoma (MTC) patients with increased calcitonin (Ctn) levels but negative CI after thyroidectomy. Fifteen patients with raised Ctn levels and/or CI evidence of recurrence underwent {sup 68}Ga-DOTATATE PET-CT, {sup 111}In-octreotide SPECT-CT and CI. Histopathology, CI and biochemical/clinical/imaging follow-up were used as the reference standard. PET/CT, SPECT/CT and CI were compared in a lesion-based and organ-based analysis. PET/CT evidenced recurrence in 14 of 15 patients. There were 13 true positive (TP), 1 true negative (TN), 1 false positive (FP) and no false negative (FN) cases, resulting in a sensitivity and accuracy of 100% and 93%. SPECT/CT was positive in 6 of 15 cases. There were 6 TP, 2 TN, 7 FN and no FP cases, resulting in a sensitivity of 46% and accuracy of 53%. CI procedures detected tumor lesions in 14 of 15 patients. There were 13 TP, 1TN, 1 FP and no FN cases with a sensitivity of 100% and accuracy of 93%. A significantly higher number of lesions was detected by PET/CT (112 lesions, p = 0.005) and CI (109 lesions, p = 0.005) in comparison to SPECT/CT (16 lesions). There was no significant difference between PET/CT and CI for the total number of detected lesions (p = 0.734). PET/CT detected more lesions than SPECT/CT regardless of the organ. PET/CT detected more bone lesions but missed some neck nodal metastases evidenced by CI. The number of lesions per region demonstrated by PET/CT and CI were similar in the other sites. {sup 68}Ga-DOTATATE PET/CT is superior to {sup 111}In-octreotide SPECT/CT for the detection of recurrent MTC demonstrating a significantly higher number of lesions. {sup 68}Ga-DOTATATE PET/CT showed a superior detection rate compared to CI in demonstrating bone metastases. (orig.)

PET/CT versus bone marrow biopsy in the initial evaluation of bone marrow infiltration in various pediatric malignancies.

Science.gov (United States)

Zapata, Claudia P; Cuglievan, Branko; Zapata, Catalina M; Olavarrieta, Raquel; Raskin, Scott; Desai, Kavita; De Angulo, Guillermo

2018-02-01

Accurate staging is essential in the prognosis and management of pediatric malignancies. Current protocols require screening for marrow infiltration with bone marrow biopsy (BMB) as the gold standard. Positron emission tomography-computed tomography (PET-CT) is commonly used to complete the staging process and can also be used to evaluate marrow infiltration. To compare PET-CT and BMB in the initial evaluation of bone marrow infiltration in pediatric cancers. We retrospectively reviewed new cases of EWS, rhabdomyosarcoma, neuroblastoma, and lymphoma diagnosed between January 2009 and October 2014. Each case had undergone both PET-CT and BMB within 4 weeks without treatment in the interval between screening modalities. We reviewed 69 cases. Bone marrow infiltration was demonstrated in 34 cases by PET-CT and in 18 cases by BMB. The sensitivity and negative predictive value of PET-CT were both 100%. Interestingly, the cases in which infiltration was not detected on BMB had an abnormal marrow signal on PET-CT focal or distant to iliac crest. PET-CT has a high sensitivity when assessing marrow infiltration in pediatric malignancies. Advances in radiologic modalities may obviate the use of invasive, painful, and costly procedures like BMB. Furthermore, biopsy results are limited by insufficient tissue or the degree of marrow infiltration (diffuse vs. focal disease). PET-CT can improve the precision of biopsy when used as a guiding tool. This study proposes the use of PET-CT as first-line screening for bone marrow infiltration to improve the accuracy of staging in new diagnoses. © 2017 Wiley Periodicals, Inc.

An evaluation of the subtraction photoshop software accuracy to detect minor changes in optical density by radiovisiography

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Talaeipour AR.

2004-06-01

Full Text Available Statement of Problem: Subtraction is a newly presented radiography technique to detect minor density"nchanges that are not visible by conventional radiography."nPurpose: The aim of this In-vitro study was to evaluate the efficacy of photoshop subtraction software for"ndetecting minor density changes between two dental images."nMaterials and Methods: In this research, five dried human mandibles were held in fixed position while thin"naluminium sheets were superimposed on each mandible on the 1th and 2nd molar teeth regions."nA reference image, without aluminium sheet placement, was obtained from each mandible subsequently series"nconsist of 20 images with aluminium sheets, ranging from 50p. to "5Q0"x were recorded by radiovisiography"n(RVG system. Initial images were subtracted from subsequent ones by Photoshop subtraction software. The"ndifference in density between the two images at the 1st and 2nd molar sites was related to the aluminium"nsheets. The optical density of aluminium sheets was determined by densitometer."nResults: In the present study, 6.6% of the optical density changes of the minimum aluminium thickness as"n300u. could be detected by photoshop software software."nConclusion: The findings of this study showed that the accuracy of photoshop subtraction software was equal"nto that of the conventional subtraction softwares. Additionally, the accuracy of this software was proved to be"nsuitable for clinical investigations of small localized changes in alveolar bone.

The Role of Bone Subtraction Computed Tomographic Angiography in Determining Intracranial Aneurysms in Non-Traumatic Subarachnoid Hemorrhage

International Nuclear Information System (INIS)

Kayhan, Aysegul; Koc, Osman; Keskin, Suat; Keskin, Fatih

2014-01-01

The presence of blood in the subarachnoid space is an acute pathology with a serious risk of death and complications. The most common etiology (approximately 80%) is intracranial aneurysm. The aim of this study was to assess the role of bone subtracted computed tomographic angiography (BSCTA), a novel and noninvasive method for determining and characterizing intracranial aneurysms. Sixty consecutive patients with clinically suspected non-traumatic subarachnoid hemorrhage (SAH) were considered to enter the study. The subtraction quality was inadequate in ten patients; thus, they were excluded, leaving 50 patients (84.4%) in the study. Bone subtracted and non-subtracted 3D images were obtained from the BSCTA raw data sets. All images obtained by digital subtraction angiography (DSA), BSCTA, and computed tomographic angiography (CTA) were evaluated for the presence or absence of an aneurysm and the location, minimal sac diameter, and neck size ratio of the aneurysm. DSA was considered as the gold standard during the evaluation of the data. Of the 50 patients who participated in this study, 11 had no aneurysms as determined by both CTA and DSA. Examination of the remaining 39 patients revealed the presence of 51 aneurysms. While 3D-CTA could not detect six aneurysms that were located in the base of the skull, 3D-BSCTA easily detected them. Moreover, five aneurysms were only partially detected by 3D-CTA. According to this data, the sensitivity of 3D-BSCTA and 3D-CTA was calculated as 98% and 86.3%, respectively; the specificity was calculated as 100% and 90.9%, respectively, per aneurysm; and the sensitivity of 100% for 3D-BSCTA and 98% for 3D-CTA was achieved by using combined images with multi-planar reconstruction (MPR) and maximum intensity projection (MIP). BSCTA detected and characterized the aneurysms as well as DSA, and BSCTA and DSA gave concordant results in detecting aneurysms. BSCTA is easily accessible, less time consuming, and most importantly, a non

The Role of Bone Subtraction Computed Tomographic Angiography in Determining Intracranial Aneurysms in Non-Traumatic Subarachnoid Hemorrhage

Science.gov (United States)

Kayhan, Aysegul; Koc, Osman; Keskin, Suat; Keskin, Fatih

2014-01-01

Background: The presence of blood in the subarachnoid space is an acute pathology with a serious risk of death and complications. The most common etiology (approximately 80%) is intracranial aneurysm. Objectives: The aim of this study was to assess the role of bone subtracted computed tomographic angiography (BSCTA), a novel and noninvasive method for determining and characterizing intracranial aneurysms. Patients and Methods: Sixty consecutive patients with clinically suspected non-traumatic subarachnoid hemorrhage (SAH) were considered to enter the study. The subtraction quality was inadequate in ten patients; thus, they were excluded, leaving 50 patients (84.4%) in the study. Bone subtracted and non-subtracted 3D images were obtained from the BSCTA raw data sets. All images obtained by digital subtraction angiography (DSA), BSCTA, and computed tomographic angiography (CTA) were evaluated for the presence or absence of an aneurysm and the location, minimal sac diameter, and neck size ratio of the aneurysm. DSA was considered as the gold standard during the evaluation of the data. Results: Of the 50 patients who participated in this study, 11 had no aneurysms as determined by both CTA and DSA. Examination of the remaining 39 patients revealed the presence of 51 aneurysms. While 3D-CTA could not detect six aneurysms that were located in the base of the skull, 3D-BSCTA easily detected them. Moreover, five aneurysms were only partially detected by 3D-CTA. According to this data, the sensitivity of 3D-BSCTA and 3D-CTA was calculated as 98% and 86.3%, respectively; the specificity was calculated as 100% and 90.9%, respectively, per aneurysm; and the sensitivity of 100% for 3D-BSCTA and 98% for 3D-CTA was achieved by using combined images with multi-planar reconstruction (MPR) and maximum intensity projection (MIP). BSCTA detected and characterized the aneurysms as well as DSA, and BSCTA and DSA gave concordant results in detecting aneurysms. Conclusions: BSCTA is

A comparison of conventional maximum intensity projection with a new depth-specific topographic mapping technique in the CT analysis of proximal tibial subchondral bone density

International Nuclear Information System (INIS)

Johnston, James D.; Kontulainen, Saija A.; Masri, Bassam A.; Wilson, David R.

2010-01-01

The objective was to identify subchondral bone density differences between normal and osteoarthritic (OA) proximal tibiae using computed tomography osteoabsorptiometry (CT-OAM) and computed tomography topographic mapping of subchondral density (CT-TOMASD). Sixteen intact cadaver knees from ten donors (8 male:2 female; mean age:77.8, SD:7.4 years) were categorized as normal (n = 10) or OA (n = 6) based upon CT reconstructions. CT-OAM assessed maximum subchondral bone mineral density (BMD). CT-TOMASD assessed average subchondral BMD across three layers (0-2.5, 2.5-5 and 5-10 mm) measured in relation to depth from the subchondral surface. Regional analyses of CT-OAM and CT-TOMASD included: medial BMD, lateral BMD, and average BMD of a 10-mm diameter area that searched each medial and lateral plateau for the highest ''focal'' density present within each knee. Compared with normal knees, both CT-OAM and CT-TOMASD demonstrated an average of 17% greater whole medial compartment density in OA knees (p 0.05). CT-TOMASD focal region analyses revealed an average of 24% greater density in the 0- to 2.5-mm layer (p = 0.003) and 36% greater density in the 2.5- to 5-mm layer (p = 0.034) in OA knees. Both CT-OAM and TOMASD identified higher medial compartment density in OA tibiae compared with normal tibiae. In addition, CT-TOMASD indicated greater focal density differences between normal and OA knees with increased depth from the subchondral surface. Depth-specific density analyses may help identify and quantify small changes in subchondral BMD associated with OA disease onset and progression. (orig.)

Prospective evaluation of MR overlay on real-time fluoroscopy for percutaneous extremity biopsies of bone lesions visible on MRI but not on CT in children in the interventional radiology suite

International Nuclear Information System (INIS)

Shellikeri, Sphoorti; Vatsky, Seth; Srinivasan, Abhay; Krishnamurthy, Ganesh; Zhu, Xiaowei; Keller, Marc S.; Cahill, Anne Marie; Setser, Randolph M.

2018-01-01

Magnetic resonance imaging (MRI) often provides better visualization of bone marrow abnormalities than computed tomography (CT) or fluoroscopy, but bone biopsies are usually performed using conventional CT or, more recently, C-arm CT guidance. Biopsies of bone lesions solely visible on MRI are often challenging to localize and require the operator to review the MRI on a separate console to correlate with MRI anatomical landmarks during the biopsy. The MR overlay technique facilitates such biopsies in the angiographic suite by allowing the pre-procedural 3-D MRI to be overlaid on intraprocedural 2-D fluoroscopy. This study describes our initial experience with the MR overlay technique in the angiography suite during pediatric percutaneous extremity bone biopsies of lesions visible on MRI but not on CT or fluoroscopy and demonstrates its utility in relevant clinical cases. (orig.)

Prospective evaluation of MR overlay on real-time fluoroscopy for percutaneous extremity biopsies of bone lesions visible on MRI but not on CT in children in the interventional radiology suite

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Shellikeri, Sphoorti; Vatsky, Seth; Srinivasan, Abhay; Krishnamurthy, Ganesh; Zhu, Xiaowei; Keller, Marc S.; Cahill, Anne Marie [Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); Setser, Randolph M. [Siemens Medical Solutions USA, Inc., Hoffman Estates, IL (United States)

2018-02-15

Magnetic resonance imaging (MRI) often provides better visualization of bone marrow abnormalities than computed tomography (CT) or fluoroscopy, but bone biopsies are usually performed using conventional CT or, more recently, C-arm CT guidance. Biopsies of bone lesions solely visible on MRI are often challenging to localize and require the operator to review the MRI on a separate console to correlate with MRI anatomical landmarks during the biopsy. The MR overlay technique facilitates such biopsies in the angiographic suite by allowing the pre-procedural 3-D MRI to be overlaid on intraprocedural 2-D fluoroscopy. This study describes our initial experience with the MR overlay technique in the angiography suite during pediatric percutaneous extremity bone biopsies of lesions visible on MRI but not on CT or fluoroscopy and demonstrates its utility in relevant clinical cases. (orig.)

Evaluation of peripheral artery stent with 64-slice multi-detector row CT angiography: Prospective comparison with digital subtraction angiography

International Nuclear Information System (INIS)

Li Xiaoming; Li Yuhua; Tian Jianming; Xiao Yi; Lu Jianping; Jing Zaiping; Sheng Jing; Edwin, Angela; Wu Fanghong

2010-01-01

Purpose: To assess the accuracy of 64-slice multi-detector row computed tomography (MDCT) angiography in the evaluation of peripheral artery in-stent or peristent restenosis, with conventional digital subtraction angiography (DSA) as the reference standard. Materials and methods: Forty-one patients (30 men, 11 women; mean age, 69.8 ± 9.2 years) with symptomatic peripheral arterial occlusive disease after peripheral artery stenting (81 stented lesions) underwent both conventional DSA and 64-slice MDCT angiography. Each stent was classified as evaluable or unevaluable, and every stent was divided into three segments (proximal stent, stent body, and distal stent), resulting in 243 segments. For evaluation, stenosis was graded as follows: 1, none or slight stenosis (<25%); 2, mild stenosis (25-49%); 3, moderate stenosis (50-74%); 4, severe stenosis or total occlusion (≥75%). Two readers evaluated all CT angiograms with regard to narrowing of in-stent or peristent restenosis by consensus. Results were compared with findings of the DSA. Results: Of 81 stents, 62 (76.5%) were determined to be assessable. The metal artifact of the gold marker and motion artifact increased uninterpretability of the images of stents. Overall, 24 of 28 in-stent restenosis and 38 of 53 persistent restenosis were correctly detected by MDCT (85.7% and 71.7% sensitivity). In evaluable stents, 21 of 22 in-stent restenoses and 27 of 28 persistent restenosis were correctly detected (95.4% and 96.4% sensitivity). Additionally, as the grade of stenosis increases, the mean level of CT values in the stent lumina decreases linearly accordingly. Conclusion: 64-Slice MDCT has a high accuracy for the detection of significant in-stent or peristent restenosis of assessable stents in patients with peripheral artery stent implantation and therefore can be considered as a valuable noninvasive technique for stent surveillance.

Assessment of Bone Metastases in Patients with Prostate Cancer—A Comparison between 99mTc-Bone-Scintigraphy and [68Ga]Ga-PSMA PET/CT

Directory of Open Access Journals (Sweden)

Lena Thomas

2017-07-01

Full Text Available Purpose: Bone scintigraphy is the standard of reference in bone metastases in prostate cancer patients. However, new radiotracers employed in prostate-specific membrane antigen (PSMA-ligands has led to the growing importance of PET/CT as diagnostic tool. The aim of our study was to investigate the difference between bone scan and PSMA-PET/CT for the detection of bone metastases in prostate cancer. Methods: Thirty patients with bone metastases originating from prostate cancer were examined by 99mTc-MDP bone scan and 68Ga-PSMA-PET/CT within an average of 21 days. Bone scans were analyzed visually according to the number of lesions and using the software package ExiniBONE by Exini Diagnostics. PET/CT data was analyzed visually. Numbers of detected lesions were compared for the different methods for the whole patient and for different regions. In addition, results were compared to serum prostate-specific antigen (PSA, alkaline phosphatase (ALP, bone alkaline phosphatase (bALP, pro gastrin releasing peptide (pGRP and eastern cooperative oncology group (ECOG performance status. Results: In the bone scans, visual and semiautomatic lesion detection showed similar results with an average of 19.4 and 17.8 detected bone lesion per patient. However, in PSMA-PET/CT, on average double the numbers of lesions (40.0 were detected. The largest differences were found in the thorax and pelvis, which can be explained by the advantages of tomographic imaging. Bland-Altman analysis showed greater differences in patients with large numbers of bone metastases. Conclusion: No significant difference was found when using semiautomatic analysis compared to visual reading for bone scans. Fewer bone metastases were detected in bone scans than in PSMA-PET/CT. However, in none of our patients would the difference have led to clinical consequences. Therefore, it seems that for patients undergoing PSMA-PET/CT, there is no need to perform additional bone scans if the appropriate

Diagnostic accuracy of the detection of bone change using panoramic TMJ projection. Comparative study with limited cone-beam CT

International Nuclear Information System (INIS)

Araki, Kazuyuki; Okano, Tomohiro; Kataoka, Ryuta; Honda, Kazuya; Endo, Atsushi; Kaneko, Norikazu; Funahashi, Itsuo

2008-01-01

Panoramic temporoman joint (TMJ) projection is one of the alternative methods of conventional radiography, such as transcranial projection, for diagnosing temporomandibular joint disorder. There have been a few reports describing the diagnostic ability of this method. We evaluated the diagnostic accuracy of detecting bone change with panoramic TMJ projection. Fifty TMJs in 25 patients were examined. All TMJs were examined by panoramic TMJ projection (Hyper XF) and limited cone-beam CT (3D Accuitomo FPD; 3DX). Two observers evaluated the presence of bone change in the TMJ region using panoramic TMJ projection. One other observer evaluated the limited cone-beam CT for the presence and the pattern of bone changes in the TMJ region as the gold standard. Panoramic TMJ findings were evaluated with regard to sensitivity, specificity, and accuracy. Sensitivity, specificity and accuracy of the panoramic TMJ projection were 0.86, 0.76, and 0.82, respectively. These results and those of previous reports on other radiographic methods for TMJ suggest that panoramic TMJ projection is a useful method of screening for bone change due to TMJ disorder. (author)

Skull base osteomyelitis: role of three phase and hybrid SPECT/CT bone scintigraphy

International Nuclear Information System (INIS)

Chakraborty, D.; Bhattacharaya, A.; Kamaleshwaran, K.K.; Mittal, B.R.; Aggarwal, K.; Singh, B.; Bhoil, A.

2010-01-01

Full text: Skull base osteomyelitis is the infection that has spread to the skull base, beyond the external auditory canal and seen in advanced stage of malignant otitis externa. Early diagnosis of this condition includes the use of bone scintigraphy since clinical assessment alone cannot differentiate the skull base osteomyelitis from the severe type of otitis externa in which there is no extension to the adjacent bone. Objective: To determine the role of three phase bone scintigraphy and delayed SPECT/CT in detection of skull base osteomyelitis in patients with malignant otitis externa. Material and Methods: Clinical records of 20 patients (14 Males and 6 Females; mean age 72 yrs) of otitis externa with suspected skull base involvement referred for bone scintigraphies were analyzed retrospectively. Three phase bone scintigraphy was acquired under dual detector gamma camera after intravenous injection of 20 mCi (740 MBq) 99m Tc-MDP followed by SPECT/CT of the skull. Scintigraphic findings were compared with clinical symptoms, signs and diagnostic CT scan findings. Results: All the patients except one were diabetic and having elevated ESR. 18 patients presented with bilateral symptoms and rest unilateral. Cranial nerves were involved in 8 patients (40%). Ear discharge culture sensitivity report was found in three patients; it was positive for Pseudomonas aeruginosa for two patients and in Diptheroids for one. In 9 patients (45%) increased flow of tracer and 10 patients (50%) increased blood pool phase in the temporal region was found. Delayed phase images showed increased uptake in skull bone in 19 patients (95%). Hybrid SPECT/CT of the skull localized areas of increased tracer uptake to the mastoid part in 15 patients (75%), petrous part in 11 patients (55%), sphenoid in 3 patients (15%) and zygomatic bone in one patient (5%) with CT showing destructive changes in 5 patients (25%) which were corroborated with diagnostic CT findings. SPECT/CT along with three phase

Xenon-enhanced CT using subtraction CT: Basic and preliminary clinical studies for comparison of its efficacy with that of dual-energy CT and ventilation SPECT/CT to assess regional ventilation and pulmonary functional loss in smokers

International Nuclear Information System (INIS)

Ohno, Yoshiharu; Yoshikawa, Takeshi; Takenaka, Daisuke; Fujisawa, Yasuko; Sugihara, Naoki; Kishida, Yuji; Seki, Shinichiro; Koyama, Hisanobu; Sugimura, Kazuro

2017-01-01

Purpose: To prospectively and directly compare the capability for assessments of regional ventilation and pulmonary functional loss in smokers of xenon-ventilation CT obtained with the dual-energy CT (DE-CT) and subtraction CT (Sub-CT) Materials and methods: Twenty-three consecutive smokers (15 men and 8 women, mean age: 69.7 ± 8.7 years) underwent prospective unenhanced and xenon-enhanced CTs, the latter by Sub-CT and DE-CT methods, ventilation SPECT and pulmonary function tests. Sub-CT was generated from unenhanced and xenon-enhanced CT, and all co-registered SPECT/CT data were produced from SPECT and unenhanced CT data. For each method, regional ventilation was assessed by using a 11-point scoring system on a per-lobe basis. To determine the functional lung volume by each method, it was also calculated for individual sublets with a previously reported method. To determine inter-observer agreement for each method, ventilation defect assessment was evaluated by using the χ2 test with weighted kappa statistics. For evaluation of the efficacy of each method for pulmonary functional loss assessment, functional lung volume was correlated with%FEV 1 . Results: Each inter-observer agreement was rated as substantial (Sub-CT: κ = 0.69, p < 0.0001; DE-CT: κ = 0.64, p < 0.0001; SPECT/CT: κ = 0.64, p < 0.0001). Functional lung volume for each method showed significant to good correlation with%FEV 1 (Sub-CT: r = 0.72, p = 0.0001; DE-CT: r = 0.74, p < 0.0001; SPECT/CT: r = 0.66, p = 0.0006). Conclusion: Xenon-enhanced CT obtained by Sub-CT can be considered at least as efficacious as that obtained by DE-CT and SPECT/CT for assessment of ventilation abnormality and pulmonary functional loss in smokers.

Xenon-enhanced CT using subtraction CT: Basic and preliminary clinical studies for comparison of its efficacy with that of dual-energy CT and ventilation SPECT/CT to assess regional ventilation and pulmonary functional loss in smokers

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Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.jp [Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe (Japan); Yoshikawa, Takeshi [Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe (Japan); Takenaka, Daisuke [Department of Radiology, Hyogo Cancer Center, Akashi (Japan); Fujisawa, Yasuko; Sugihara, Naoki [Toshiba Medical Systems Corporation, Otawara (Japan); Kishida, Yuji; Seki, Shinichiro; Koyama, Hisanobu; Sugimura, Kazuro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine (Japan)

2017-01-15

Purpose: To prospectively and directly compare the capability for assessments of regional ventilation and pulmonary functional loss in smokers of xenon-ventilation CT obtained with the dual-energy CT (DE-CT) and subtraction CT (Sub-CT) Materials and methods: Twenty-three consecutive smokers (15 men and 8 women, mean age: 69.7 ± 8.7 years) underwent prospective unenhanced and xenon-enhanced CTs, the latter by Sub-CT and DE-CT methods, ventilation SPECT and pulmonary function tests. Sub-CT was generated from unenhanced and xenon-enhanced CT, and all co-registered SPECT/CT data were produced from SPECT and unenhanced CT data. For each method, regional ventilation was assessed by using a 11-point scoring system on a per-lobe basis. To determine the functional lung volume by each method, it was also calculated for individual sublets with a previously reported method. To determine inter-observer agreement for each method, ventilation defect assessment was evaluated by using the χ2 test with weighted kappa statistics. For evaluation of the efficacy of each method for pulmonary functional loss assessment, functional lung volume was correlated with%FEV{sub 1}. Results: Each inter-observer agreement was rated as substantial (Sub-CT: κ = 0.69, p < 0.0001; DE-CT: κ = 0.64, p < 0.0001; SPECT/CT: κ = 0.64, p < 0.0001). Functional lung volume for each method showed significant to good correlation with%FEV{sub 1} (Sub-CT: r = 0.72, p = 0.0001; DE-CT: r = 0.74, p < 0.0001; SPECT/CT: r = 0.66, p = 0.0006). Conclusion: Xenon-enhanced CT obtained by Sub-CT can be considered at least as efficacious as that obtained by DE-CT and SPECT/CT for assessment of ventilation abnormality and pulmonary functional loss in smokers.

Influence of homeopathic treatment with comfrey on bone density around titanium implants: a digital subtraction radiography study in rats.

Science.gov (United States)

Sakakura, Celso Eduardo; Neto, Rubens Spin; Bellucci, Marina; Wenzel, Ann; Scaf, Gulnara; Marcantonio, Elcio

2008-06-01

The objective of this study was to evaluate the influence of homeopathic treatment with comfrey (Shymphytum officinalis 6CH) on radiographic bone density and area around titanium implants. Forty-eight rats were divided into two groups of 24 animals each: a control group (C) and a test group (SO). Each animal received one titanium micro-implant placed in the tibia. The animals in Group SO were subjected to 10 drops of comfrey 6CH per day mixed into their drinking water until the day of sacrifice. Eight animals of each group were sacrificed at 7, 14 and 28 days post-surgery, respectively. Standardized digital radiographs were obtained on the day of implant installation (baseline images) and on the day of sacrifice (final images). Digital subtraction of the two corresponding images was performed to evaluate changes in bone density and the area related to change around the implant between baseline and final images. Subtraction images demonstrated that a significant difference existed in mean shade of gray at 14 days post-surgery between Group SO (mean 175.3+/-14.4) and Group C (mean 146.2+/-5.2). Regarding the area in pixels corresponding to the bone gain in Group SO, the differences observed between the sacrifice periods and groups were only significant at 7 days sacrifice between Group SO (mean 171.2+/-21.9) and Group C (mean 64.5+/-60.4). Within the limits of this study, comfrey administration promotes an increase in radiographic bone density around titanium implants in the initial period of bone healing.

(18)F-FDG dynamic PET/CT in patients with multiple myeloma: patterns of tracer uptake and correlation with bone marrow plasma cell infiltration rate.

Science.gov (United States)

Sachpekidis, Christos; Mai, Elias K; Goldschmidt, Hartmut; Hillengass, Jens; Hose, Dirk; Pan, Leyun; Haberkorn, Uwe; Dimitrakopoulou-Strauss, Antonia

2015-06-01

The value of F-FDG PET in the diagnostic approach of multiple myeloma (MM) remains incompletely elicited. Little is known about the kinetics of F-FDG in the bone marrow and extramedullary sites in MM. This study aimed to evaluate quantitative data on kinetics and distribution patterns of F-FDG in MM patients with regard to pelvic bone marrow plasma cell infiltration. The study included 40 patients with primary MM. Dynamic PET/CT scanning of the lower lumbar spine and pelvis was performed after the administration of F-FDG. Whole-body PET/CT studies were performed. Sites of focal increased tracer uptake were considered as highly suggestive of myelomatous involvement after taking into account the patient history and CT findings. Bone marrow of the os ilium without pathologic tracer accumulation served as reference. The evaluation of dynamic PET/CT studies was based in addition to the conventional visual (qualitative) assessment, on semiquantitative (SUV) calculations, as well as on absolute quantitative estimations after application of a 2-tissue compartment model and a noncompartmental approach. F-FDG quantitative information and corresponding distribution patterns were correlated with pelvic bone marrow plasma cell infiltration. Fifty-two myelomatous lesions were detected in the pelvis. All parameters in suspected MM lesions ranged in significantly higher levels than in reference tissue (P PET/CT imaging demonstrated 4 patterns of tracer uptake; these are as follows: negative, focal, diffuse, and mixed (focal/diffuse) tracer uptake. Patients with a mixed pattern of radiotracer uptake had the highest mean plasma cell infiltration rate in their bone marrow, whereas those with negative PET/CT scans demonstrated the lowest bone marrow plasma cell infiltration. In total, 265 focal myeloma-indicative F-FDG-avid lesions were detected, 129 of which correlated with low-dose CT osteolytic findings. No significant correlation between the number of focal lesions detected in PET/CT

Digital subtraction angiography in ischemic cerebrovascular accidents

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Manelfe, C.; Bonafe, A.; Ducos de Lahitte, M.; Rascol, A.; Prere, J.; Guiraud, B.; Marc-Vergnes, J.P. (Hopital Purpan, 31 - Toulouse (France))

1983-12-29

Recent advances in computer and radiological technology have permitted reassessment of intravenous angiography in the evaluation of cerebrovascular disorders. Although digital subtraction angiography is a relatively new technique, it has rapidly gained a widespread acceptance. It has extended the use of angiography to outpatients and to people in whom conventional angiography is contraindicated. This reliable, safe, and relatively noninvasive technique offers the user two benefits: real-time subtraction and enhanced image quality. The system allows angiographic evaluation of the extracranial and intracranial vessels by means of intravenous injection of contrast material. Extracranial studies clearly demonstrate stenoses and occlusions of the major cervicocephalic arteries. Intracranial studies usually detect major cerebrovascular occlusions and provide insight into the collateral flow patterns. Intravenous digital subtraction angiography permits accurate assessment of cervicocephalic vessels after surgical repair. Although intravenous digital subtraction angiography obviates the need for conventional angiography in many cases, movements from the patients, or superimposition of vascular structures can substantially degrade the quality of the images. Digital subtraction angiography with intra-arterial injection of contrast medium will be contemplated in patients with poor intravenous digital subtraction angiography studies prior to surgery.

Digital subtraction angiography in ischemic cerebrovascular accidents

International Nuclear Information System (INIS)

Manelfe, C.; Bonafe, A.; Ducos de Lahitte, M.; Rascol, A.; Prere, J.; Guiraud, B.; Marc-Vergnes, J.P.

1983-01-01

Recent advances in computer and radiological technology have permitted reassessment of intravenous angiography in the evaluation of cerebrovascular disorders. Although digital subtraction angiography is a relatively new technique, it has rapidly gained a widespread acceptance. It has extended the use of angiography to outpatients and to people in whom conventional angiography is contraindicated. This reliable, safe, and relatively noninvasive technique offers the user two benefits: real-time subtraction and enhanced image quality. The system allows angiographic evaluation of the extracranial and intracranial vessels by means of intravenous injection of contrast material. Extracranial studies clearly demonstrate stenoses and occlusions of the major cervicocephalic arteries. Intracranial studies usually detect major cerebrovascular occlusions and provide insight into the collateral flow patterns. Intravenous digital subtraction angiography permits accurate assessment of cervicocephalic vessels after surgical repair. Although intravenous digital subtraction angiography obviates the need for conventional angiography in many cases, movements from the patients, or superimposition of vascular structures can substantially degrade the quality of the images. Digital subtraction angiography with intra-arterial injection of contrast medium will be contemplated in patients with poor intravenous digital subtraction angiography studies prior to surgery [fr

Trapezium Bone Density-A Comparison of Measurements by DXA and CT.

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Breddam Mosegaard, Sebastian; Breddam Mosegaard, Kamille; Bouteldja, Nadia; Bæk Hansen, Torben; Stilling, Maiken

2018-01-18

Bone density may influence the primary fixation of cementless implants, and poor bone density may increase the risk of implant failure. Before deciding on using total joint replacement as treatment in osteoarthritis of the trapeziometacarpal joint, it is valuable to determine the trapezium bone density. The aim of this study was to: (1) determine the correlation between measurements of bone mineral density of the trapezium obtained by dual-energy X-ray absorptiometry (DXA) scans by a circumference method and a new inner-ellipse method; and (2) to compare those to measurements of bone density obtained by computerized tomography (CT)-scans in Hounsfield units (HU). We included 71 hands from 59 patients with a mean age of 59 years (43-77). All patients had Eaton-Glickel stage II-IV trapeziometacarpal (TM) joint osteoarthritis, were under evaluation for trapeziometacarpal total joint replacement, and underwent DXA and CT wrist scans. There was an excellent correlation (r = 0.94) between DXA bone mineral density measures using the circumference and the inner-ellipse method. There was a moderate correlation between bone density measures obtained by DXA- and CT-scans with (r = 0.49) for the circumference method, and (r = 0.55) for the inner-ellipse method. DXA may be used in pre-operative evaluation of the trapezium bone quality, and the simpler DXA inner-ellipse measurement method can replace the DXA circumference method in estimation of bone density of the trapezium.

Trapezium Bone Density—A Comparison of Measurements by DXA and CT

Directory of Open Access Journals (Sweden)

Sebastian Breddam Mosegaard

2018-01-01

Full Text Available Bone density may influence the primary fixation of cementless implants, and poor bone density may increase the risk of implant failure. Before deciding on using total joint replacement as treatment in osteoarthritis of the trapeziometacarpal joint, it is valuable to determine the trapezium bone density. The aim of this study was to: (1 determine the correlation between measurements of bone mineral density of the trapezium obtained by dual-energy X-ray absorptiometry (DXA scans by a circumference method and a new inner-ellipse method; and (2 to compare those to measurements of bone density obtained by computerized tomography (CT-scans in Hounsfield units (HU. We included 71 hands from 59 patients with a mean age of 59 years (43–77. All patients had Eaton–Glickel stage II–IV trapeziometacarpal (TM joint osteoarthritis, were under evaluation for trapeziometacarpal total joint replacement, and underwent DXA and CT wrist scans. There was an excellent correlation (r = 0.94 between DXA bone mineral density measures using the circumference and the inner-ellipse method. There was a moderate correlation between bone density measures obtained by DXA- and CT-scans with (r = 0.49 for the circumference method, and (r = 0.55 for the inner-ellipse method. DXA may be used in pre-operative evaluation of the trapezium bone quality, and the simpler DXA inner-ellipse measurement method can replace the DXA circumference method in estimation of bone density of the trapezium.

Femoral head vascularisation in Legg-Calve-Perthes disease: comparison of dynamic gadolinium-enhanced subtraction MRI with bone scintigraphy

International Nuclear Information System (INIS)

Lamer, Sylvie; Dorgeret, Sophie; Brillet, Pierre-Yves; Hassan, Max; Sebag, Guy H.; Khairouni, Abdeslam; Mazda, Keyvan; Bacheville, Eric; Pennecot, Georges F.; Bloch, Juliette

2002-01-01

Heading AbstractBackground. It has been reported that MRI using a dynamic gadolinium-enhanced subtraction technique can allow the early identification of ischaemia and the pattern of revascularisation in Legg-Calve-Perthes (LCP) disease with increased spatial and contrast resolution. Therefore, dynamic gadolinium-enhanced subtraction (DGS) MRI may be a possible non-ionising substitute for bone scintigraphy.Objective. The purpose of this prospective study was to compare DGS MRI and bone scintigraphy in the assessment of femoral head perfusion in LCP disease.Materials and methods. Twenty-six DGS MR images and bone scintigraphies of 25 hips in 23 children were obtained at different stages of LCP disease; three stage I, 12 stage II, six stage III and five stage IV (Waldenstroem classification). The extent of necrosis, epiphyseal revascularisation pathways (lateral pillar, medial pillar, and/or transphyseal perfusion) and metaphyseal changes were analysed.Results. Total agreement between both techniques was noted in the depiction of epiphyseal necrosis (kappa=1), and metaphyseal abnormalities (kappa=0.9). DGS MRI demonstrated better revascularisation in the lateral (kappa=0.62) and medial pillars (kappa=0.52). The presence of basal transphyseal reperfusion was more conspicuous with MRI.Conclusions. DGS MRI allows early detection of epiphyseal ischaemia and accurate analysis of the different revascularisation patterns. These changes are directly related to the prognosis of LCP disease and can aid therapeutic decision making. (orig.)

Craniofacial and temporal bone CT findings in cleidocranial dysplasia

International Nuclear Information System (INIS)

Gonzalez, Guido E.; Caruso, Paul A.; Curtin, Hugh D.; Small, Juan E.; Jyung, Robert W.; Troulis, Maria J.

2008-01-01

Cleidocranial dysplasia (CCD) is a multistructural polyostotic genetic disorder that results from mutation of the CBFA1 gene. Hearing loss is a frequent finding in CCD. We describe the CT craniofacial findings in CCD and provide a comprehensive discussion of the CT temporal bone findings in these patients. (orig.)

Comprehensive Assessment of Osteoporosis and Bone Fragility with CT Colonography

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Murthy, Naveen S.; Khosla, Sundeep; Clarke, Bart L.; Bruining, David H.; Kopperdahl, David L.; Lee, David C.; Keaveny, Tony M.

2016-01-01

Purpose To evaluate the ability of additional analysis of computed tomographic (CT) colonography images to provide a comprehensive osteoporosis assessment. Materials and Methods This Health Insurance Portability and Accountability Act–compliant study was approved by our institutional review board with a waiver of informed consent. Diagnosis of osteoporosis and assessment of fracture risk were compared between biomechanical CT analysis and dual-energy x-ray absorptiometry (DXA) in 136 women (age range, 43–92 years), each of whom underwent CT colonography and DXA within a 6-month period (between January 2008 and April 2010). Blinded to the DXA data, biomechanical CT analysis was retrospectively applied to CT images by using phantomless calibration and finite element analysis to measure bone mineral density and bone strength at the hip and spine. Regression, Bland-Altman, and reclassification analyses and paired t tests were used to compare results. Results For bone mineral density T scores at the femoral neck, biomechanical CT analysis was highly correlated (R2 = 0.84) with DXA, did not differ from DXA (P = .15, paired t test), and was able to identify osteoporosis (as defined by DXA), with 100% sensitivity in eight of eight patients (95% confidence interval [CI]: 67.6%, 100%) and 98.4% specificity in 126 of 128 patients (95% CI: 94.5%, 99.6%). Considering both the hip and spine, the classification of patients at high risk for fracture by biomechanical CT analysis—those with osteoporosis or “fragile bone strength”—agreed well against classifications for clinical osteoporosis by DXA (T score ≤−2.5 at the hip or spine), with 82.8% sensitivity in 24 of 29 patients (95% CI: 65.4%, 92.4%) and 85.7% specificity in 66 of 77 patients (95% CI: 76.2%, 91.8%). Conclusion Retrospective biomechanical CT analysis of CT colonography for colorectal cancer screening provides a comprehensive osteoporosis assessment without requiring changes in imaging protocols. �

Alveolar bone healing in rats: micro-CT, immunohistochemical and molecular analysis

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Jaqueline Suemi HASSUMI

2018-06-01

Full Text Available Abstract Alveolar bone healing after upper incisor extraction in rats is a classical model of preclinical studies. The underlying morphometric, cellular and molecular mechanism, however, remains imprecise in a unique study. Objectives The aim of this study was therefore to characterize the alveolar bone healing after upper incisor extraction in rats by micro computed tomographic (Micro-CT, immunohistochemical and real-time polymerase chain reaction (RT-PCR analysis. Material and Methods Thirty animals (Rattus norvegicus, Albinus Wistar were divided into three groups after upper incisors extraction at 7, 14, and 28 days. Micro-CT was evaluated based on the morphometric parameters. Subsequently, the histological analyses and immunostaining of osteoprotegerin (OPG, receptor activator of nuclear kappa B ligand (RANKL and tartrate resistant acid phosphate (TRAP was performed. In addition, RT-PCR analyses of OPG, RANKL, the runt-related transcription factor 2 (RUNX2, osteocalcin (OC, osteopontin (OPN, osterix (OST and receptor activator of nuclear kappa B (RANK were performed to determine the expression of these proteins in the alveolar bone healing. Results Micro-CT: The morphometric parameters of bone volume and trabecular thickness progressively increased over time. Consequently, a gradual decrease in trabecular separation, trabecular space and total bone porosity was observed. Immunohistochemical: There were no differences statistically significant between the positive labeling for OPG, RANKL and TRAP in the different periods. RT-PCR: At 28 days, there was a significant increase in OPG expression, while RANKL expression and the RANKL/OPG ratio both decreased over time. Conclusion Micro-CT showed the newly formed bone had favorable morphometric characteristics of quality and quantity. Beyond the RUNX2, OC, OPN, OST, and RANK proteins expressed in the alveolar bone healing, OPG and RANKL activity showed to be essential for activation of basic

SPECT/CT imaging in bone scintigraphy of a case of clavicular osteoma

International Nuclear Information System (INIS)

Yamamoto, Yuka; Nishiyama, Yoshihiro

2014-01-01

Osteoma is a benign bone-forming tumor that usually arises in the craniofacial bones and rarely in the long bones. Clavicular involvement is extremely rare. We report a 51-year-old woman with osteoma of the left clavicle. Radiograph of the left shoulder showed a well-defined lobulated blastic mass in the proximal and mid-portion of the left clavicle. Bone scintigraphy was performed 4 hours after an intravenous injection of Tc-99m hydroxymethylene diphosphonate (HMDP). Whole-body image showed a focus of intensely increased uptake in the clavicle. Single photon emission computed tomography / computed tomography (SPECT/CT) images were also acquired and clearly showed intense uptake at the tumor site. Integrated SPECT/CT imaging supplies both functional and anatomic information about bone the SPECT imaging improves sensitivity compared with planar imaging, the CT imaging provides precise localization of the abnormal uptake, and information on the shape and structure of the abnormalities improves the specificity of the diagnosis

Fibrous dysplasia mimicking bone metastasis on both bone scintigraphy and 18F FDG PET CT: Diagnostic dilemma in a patient with breast cancer

International Nuclear Information System (INIS)

KC, Sud Hir Suman; Sharma, Punit; Singh, Har Man Deep; Bal, Chand Rasekhar; Kumar, Rake Sh

2012-01-01

Bone is the most common distant site to which breast cancer metastasizes. Commonly used imaging modalities for imaging bone metastasis are bone scintigraphy, plain radiography, computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET). Although bone scintigraphy gas high sensitivity for detecting bone metastasis, its specificity is low. This is because of the fact that bone scintigraphy images secondary changes in bone rather than just tumor cells 18 F fluorodeoxyglucose ( 18 F FDG) PET CT, on the other hand, directly images the tumor cells' glucose metabolism. Unfortunately, similar to bone scintigraphy, benign bone conditions can also show increased 18 F FDG uptake on PET CT, and PET positive asymptomatic fibrous dysplasia can be misinterpreted as a metastasis. Fibrous dysplasia of bone has wide skeletal distribution, with variability of 18 F FDG uptake and CT appearance. It is therefore important to recognize the characteristics of this skeletal dysplasia, to allow differentiation from skeletal metastasis. Bone lesions with 18 F FDG uptake need to be carefully interpreted when evaluating patients with known malignancy. In doubtful cases, fibrous dysplasia should be given as a differential diagnosis and histopathological diagnosis may be warranted, as highlighted in the present case

CT assessment of the correlation between clinical examination and bone involvement in oral malignant tumors

International Nuclear Information System (INIS)

Albuquerque, Marco Antonio Portela; Oliveira, Ilka Regina Souza; Cavalcanti, Marcelo Gusmao Paraiso; Kuruoshi, Marcia Etsuko

2009-01-01

Oral cancers have a tendency to invade the surrounding bone structures, and this has a direct influence on the treatment management and on outcomes. The objective of this study was to correlate the clinical parameters (location, clinical presentation and TNM staging) of oral malignant tumors that can be associated with a potential of bone invasion and determine the accuracy of clinical examination to predict bone involvement, using computed tomography (CT). Twenty five patients, with oral malignant tumors were submitted to clinical and CT examinations. CT was considered the standard parameter to evaluate the presence of bone involvement. Clinical assessment of location, presentation form and TNM staging of the tumors were then compared to the CT findings in predicting bone involvement. Bone involvement was observed in 68% of the cases. It was predicted that tumors located in the retromolar trigone and hard palate, with a clinical aspect of infiltrative ulcer or nodule and classified in stage IV had a high potential to cause bone involvement. The clinical examination assessment of these tumors showed to be a valuable tool to predict bone invasion, with high sensitivity (82%) and specificity (87.5%), based on the results found in the CT images. No statistical significance was found between the CT and clinical examinations regarding bone involvement. The identification of some clinical parameters such as location, clinical presentation, and TNM stage, associated with a detailed clinical examination, was considered a valuable tool for the assessment of bone destruction by oral malignant tumors. (author)

Image quality of conventional images of dual-layer SPECTRAL CT: a phantom study.

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van Ommen, F; Bennink, E; Vlassenbroek, A; Dankbaar, J W; Schilham, A M R; Viergever, M A; de Jong, H W A M

2018-05-10

Spectral CT using a dual layer detector offers the possibility of retrospectively introducing spectral information to conventional CT images. In theory, the dual-layer technology should not come with a dose or image quality penalty for conventional images. In this study, we evaluate the influence of a dual-layer detector (IQon Spectral CT, Philips) on the image quality of conventional CT images, by comparing these images with those of a conventional but otherwise technically comparable single-layer CT scanner (Brilliance iCT, Philips), by means of phantom experiments. For both CT scanners conventional CT images were acquired using four adult scanning protocols: i) body helical, ii) body axial, iii) head helical and iv) head axial. A CATPHAN 600 phantom was scanned to conduct an assessment of image quality metrics at equivalent (CTDI) dose levels. Noise was characterized by means of noise power spectra (NPS) and standard deviation (SD) of a uniform region, and spatial resolution was evaluated with modulation transfer functions (MTF) of a tungsten wire. In addition, contrast-to-noise ratio (CNR), image uniformity, CT number linearity, slice thickness, slice spacing, and spatial linearity were measured and evaluated. Additional measurements of CNR, resolution and noise were performed in two larger phantoms. The resolution levels at 50%, 10% and 5% MTF of the iCT and IQon showed small but significant differences up to 0.25 lp/cm for body scans, and up to 0.2 lp/cm for head scans in favor of the IQon. The iCT and IQon showed perfect CT linearity for body scans, but for head scans both scanners showed an underestimation of the CT numbers of materials with a high opacity. Slice thickness was slightly overestimated for both scanners. Slice spacing was comparable and reconstructed correctly. In addition, spatial linearity was excellent for both scanners, with a maximum error of 0.11 mm. CNR was higher on the IQon compared to the iCT for both normal and larger phantoms with

Dosimetry comparison of pelvimetry methods using conventional radiographs and CT

International Nuclear Information System (INIS)

Resten, A.; Suissa, M.; Musset, D.; Mausoleo, F.; Valero, M.; Taylor, S.

2001-01-01

To determine the fetal and maternal exposure to radiation by use of thermoluminescent dosimeters in order to compare conventional and CT-scan X-ray. Dosimetry was performed with an anthropomorph phantom. Thermoluminescent dosimeters were positioned on the surface and in the depth of the phantom. Digital radiography of the pelvis was performed according to a standard technique. CT-scan of the pelvis was performed according to the Buthiau's technique. With CT, the dose reached 0.31 to 4.95 mGy, with a dose of 2.32 mGy for the fetal gonads. With standard technique, the doses reached 0.03 to 0.39 mGy, with a dose of 0.39 mGy for the fetal gonads. With CT the fetus and the mother were exposed to 1/10. of the total dose delivered using conventional X-rays and the dose distribution was more homogeneous. (author)

Micro-CT characterization of human trabecular bone in osteogenesis imperfecta

Science.gov (United States)

Jameson, John; Albert, Carolyne; Smith, Peter; Molthen, Robert; Harris, Gerald

2011-03-01

Osteogenesis imperfecta (OI) is a genetic syndrome affecting collagen synthesis and assembly. Its symptoms vary widely but commonly include bone fragility, reduced stature, and bone deformity. Because of the small size and paucity of human specimens, there is a lack of biomechanical data for OI bone. Most literature has focused on histomorphometric analyses, which rely on assumptions to extrapolate 3-D properties. In this study, a micro-computed tomography (μCT) system was used to directly measure structural and mineral properties in pediatric OI bone collected during routine surgical procedures. Surface renderings suggested a poorly organized, plate-like orientation. Patients with a history of bone-augmenting drugs exhibited increased bone volume fraction (BV/TV), trabecular number (Tb.N), and connectivity density (Eu.Conn.D). The latter two parameters appeared to be related to OI severity. Structural results were consistently higher than those reported in a previous histomorphometric study, but these differences can be attributed to factors such as specimen collection site, drug therapy, and assumptions associated with histomorphometry. Mineral testing revealed strong correlations with several structural parameters, highlighting the importance of a dual approach in trabecular bone testing. This study reports some of the first quantitative μCT data of human OI bone, and it suggests compelling possibilities for the future of OI bone assessment.

Usefulness of bone scintigraphic classification and quantitative evaluation of bone mineralization with X-CT and SPECT in renal osteodystrophy

International Nuclear Information System (INIS)

Okamura, Terue; Fukuda, Teruo; Inoue, Yuuichi; Koizumi, Yoshiko; Ikeda, Hozumi; Ochi, Hironobu

1987-01-01

1. Bone scintigraphy with Tc-99m-MDP was performed on 52 patients with chronic renal failure. These bone scintigrams were classified into 4 groups, each of which was correlated to laboratory data and quantitative data of bone mineralization. Group I (32 patients) showed high accumulation of Tc-99m-MDP in the bone. High level of Alk-Pase and c-PTH, low BMC/BW, low EMI number and high radionuclide activity ratio (RN ratio) were observed. Group II (9 patients) demonstrated nuclear bone images with high background activity. RN ratio was slightly higher than the normal. Group III (11 patients) showed extraosseous accumulation of Tc-99m-MDP in the lung, kidney or soft tissues. One patient belonged to Group I. High level of Ca x P product and slightly high RN ratio were observed. In both Group II and III, BMC/BW and EMI number were normal. Group IV (one patient) showed normal skeletal activity on bone scintigram. The mean duration of hemodialysis was the longest in Group I. Our scintigraphic classification is convenient and might contribute an understanding of patho-physiological bone changes in such patients. 2. Subtotal parathyroidectomy (S-PTX) was employed in 18 of 52 patients on chronic renal failure with secondary hyperparathyroidism. These patients were studied before and after S-PTX using 6 different procedures; conventional radiography, microdensitometry, bone mineral analysis, measurement of EMI number with X-CT (frontal bone), bone scintigraphy, and RN ratio (frontal bone/brain) with SPECT. On the bone scan, the diffuse increased activity in the calvarium became less prominent after S-PTX in all 18 patients. We devised a new method to quantify the bone changes revealed by the bone scan; the RN ratio with SPECT. The ratio decreased markedly after surgery. This method seems to be most useful for detecting dynamic bone changes sensitively and quantitatively. (author)

X-ray diagnosis in temporal bone anomalies

International Nuclear Information System (INIS)

Schratter, M.; Canigiani, G.; Swoboda, H.; Brunner, E.

1988-01-01

The X-ray findings in temporal bone anomalies are reviewed. Radiological procedure and examination technique are presented, as are symptoms of important anomalies. The methods available are plain film X-ray of temporal bone, multi-directional tomography, and high-resolution CT. Although some of the abnormalities are visible even in plain films, consistent use of conventional tomography or CT is necessary for correct diagnosis. This procedure is indicated not only when an abnormality is clinically obvious, but also in all cases of unexplained hearing loss without evidence of acquired disease. The advantage of CT over conventional tomography is that soft tissue anomalies, such as primary cholesteatoma or tumor simulating vascular abnormalities, can be demonstrated. In these cases CT is obligatory. (orig.) [de

CT pre-operative planning of a new semi-implantable bone conduction hearing device

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Law, Eric K.C.; Bhatia, Kunwar S.S. [Prince of Wales Hospital, The Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Hong Kong, SAR (China); Tsang, Willis S.S.; Tong, Michael C.F. [Prince of Wales Hospital, The Chinese University of Hong Kong, Department of Otorhinolaryngology, Head and Neck Surgery, Hong Kong, SAR (China); Shi, Lin [The Chinese University of Hong Kong, Department of Medicine and Therapeutics, Hong Kong, SAR (China); The Chinese University of Hong Kong, Chow Yuk Ho Technology Center for Innovative Medicine, Hong Kong, SAR (China)

2016-06-15

Accommodating a novel semi-implantable bone conduction hearing device within the temporal bone presents challenges for surgical planning. This study describes the utility of CT in pre-operative assessment of such an implant. Retrospective review of pre-operative CT, clinical and surgical records of 16 adults considered for device implantation. Radiological suitability was assessed on CT using 3D simulation software. Antero-posterior (AP) dimensions of the mastoid bone and minimum skull thickness were measured. CT planning results were correlated with operative records. Eight and five candidates were suitable for device placement in the transmastoid and retrosigmoid positions, respectively, and three were radiologically unsuitable. The mean AP diameter of the mastoid cavity was 14.6 mm for the transmastoid group and 4.6 mm for the retrosigmoid group (p < 0.05). Contracted mastoid and/or prior surgery were predisposing factors for unsuitability. Four transmastoid and five retrosigmoid positions required sigmoid sinus/dural depression and/or use of lifts due to insufficient bone capacity. A high proportion of patients being considered have contracted or operated mastoids, which reduces the feasibility of the transmastoid approach. This finding combined with the complex temporal bone geometry illustrates the importance of careful CT evaluation using 3D software for precise device simulation. (orig.)

The value of conventional tomography and CT in the diagnosis of bronchial tumors

International Nuclear Information System (INIS)

Mayr, B.; Ingrisch, H.; Haeussinger, K.; Sunder-Plassmann, L.; Huber, R.

1988-01-01

66 patients with suspected bronchial tumors were examined by conventional tomography and by CT. The results were evaluated separately by two radiologists (A and B). All diagnoses were confirmed by bronchoscopy or surgery. In evaluating individual bronchi, conventional tomography had a sensitivity of 88% (A) or 87% (B) and a specificity of 97% (A) or 95% (B); CT had a sensitivity of 95% (A and B) and a specificity of 99% (A and B). If CT is available, our experience indicates that conventional tomography is no longer indicated. (orig.) [de

Automatic bone detection and soft tissue aware ultrasound-CT registration for computer-aided orthopedic surgery.

Science.gov (United States)

Wein, Wolfgang; Karamalis, Athanasios; Baumgartner, Adrian; Navab, Nassir

2015-06-01

The transfer of preoperative CT data into the tracking system coordinates within an operating room is of high interest for computer-aided orthopedic surgery. In this work, we introduce a solution for intra-operative ultrasound-CT registration of bones. We have developed methods for fully automatic real-time bone detection in ultrasound images and global automatic registration to CT. The bone detection algorithm uses a novel bone-specific feature descriptor and was thoroughly evaluated on both in-vivo and ex-vivo data. A global optimization strategy aligns the bone surface, followed by a soft tissue aware intensity-based registration to provide higher local registration accuracy. We evaluated the system on femur, tibia and fibula anatomy in a cadaver study with human legs, where magnetically tracked bone markers were implanted to yield ground truth information. An overall median system error of 3.7 mm was achieved on 11 datasets. Global and fully automatic registration of bones aquired with ultrasound to CT is feasible, with bone detection and tracking operating in real time for immediate feedback to the surgeon.

CT appearances of unilateral cleft palate 20 years after bone graft surgery

International Nuclear Information System (INIS)

Kolbenstvedt, A.; Aaloekken, T.M.

2002-01-01

Purpose: To describe CT appearances in patients with unilateral cleft lip and palate (CLP) 20 years after bone graft surgery. Material and Methods: Eighteen consecutive patients with unilateral CLP were examined. All patients had been treated with primary closure, both in infancy and early childhood, supplemented with bone grafting at the age of around 10 years. The CT examination of the upper jaw included a dental CT program. The CT appearances of the cleft side were compared with those of the untreated non-cleft side. Results: Abnormal CT appearances included skew nasal aperture (n=17), nasal septal deviation (n=17), low floor of nasal aperture (n=15) at or towards the cleft side, and deviation of anterior nasal spine towards the non-cleft side (n=18). The posterior part of the bone cleft was visible in all patients, and the dental arch was V-shaped in 8. Conclusion: Although adherence to the present treatment protocol is considered to give satisfactory functional and cosmetic results, certain abnormalities persist. A knowledge of these is a prerequisite for a complete and final evaluation of the surgical and orthodontic regimen. Cleft palate nasal cavity abnormalities CT

CT appearances of unilateral cleft palate 20 years after bone graft surgery

Energy Technology Data Exchange (ETDEWEB)

Kolbenstvedt, A.; Aaloekken, T.M. [Rikshospitalet, Oslo (Norway). Dept. of Radiology; Arctander, K. [Rikshospitalet, Oslo (Norway). Dept. of Plastic Surgery; Johannessen, S. [Inst. of Clinical Dentistry, Oslo (Norway)

2002-11-01

Purpose: To describe CT appearances in patients with unilateral cleft lip and palate (CLP) 20 years after bone graft surgery. Material and Methods: Eighteen consecutive patients with unilateral CLP were examined. All patients had been treated with primary closure, both in infancy and early childhood, supplemented with bone grafting at the age of around 10 years. The CT examination of the upper jaw included a dental CT program. The CT appearances of the cleft side were compared with those of the untreated non-cleft side. Results: Abnormal CT appearances included skew nasal aperture (n=17), nasal septal deviation (n=17), low floor of nasal aperture (n=15) at or towards the cleft side, and deviation of anterior nasal spine towards the non-cleft side (n=18). The posterior part of the bone cleft was visible in all patients, and the dental arch was V-shaped in 8. Conclusion: Although adherence to the present treatment protocol is considered to give satisfactory functional and cosmetic results, certain abnormalities persist. A knowledge of these is a prerequisite for a complete and final evaluation of the surgical and orthodontic regimen. Cleft palate nasal cavity abnormalities CT.

Evaluation of Bone Metastasis from Hepatocellular Carcinoma Using 18F FDG PET/CT and 99mTc HDP Bone Scintigraphy: Characteristics of Soft Tissue Formation

International Nuclear Information System (INIS)

Seo, Hyo Jung; Choi, Yun Jung; Kim, Hyun Jeong; Jeong, Youg Hyu; Cho, Arthur; Lee, Jae Hoon; Yun, Mijin; Choi, Hye Jin; Lee, Jong Doo; Kang, Won Jun

2011-01-01

Bone metastasis from hepatocellular carcinoma (HCC) can present with soft tissue formation, resulting in oncologic emergency. Contrast enhanced FDG PET/CT and bone scintigraphy were compared to evaluate characteristics of bone metastases with of without soft tissue formation from HCC. of 4,151 patients with HCC, 263 patients had bone metastases. Eighty five patients with bone metastasis from HCC underwent contrast enhanced FDG PET/CT. Fifty four of the enrolled subjects had recent 99mT c HDP bone scintigraphy available for comparison. Metastatic bone lesions were identified with visual inspection on FDG PET/CT, and maximum standardized uptake value (SUVmax) was used for the quantitative analysis. Confirmation of bone metastasis was based on histopathology, combined imaging modalities, or serial follow up studies. Forty seven patients (55%) presented with soft tissue formation, while the remaining 38 patients presented without soft tissue formation. Frequent sites of bone metastases from HCC were the spine (39%), pelvis (19%), and rib cage (14%). The soft tissue formation group had more frequent bone pain (77 vs. 37%, p<0.0001), higher SUVmax (6.02 vs. 3.52, p<0.007), and higher incidence of photon defect in bone scintigraphy (75 vs. 0%) compared to the non soft tissue formation group. FDG PET/CT had higher detection rate for bone metastasis than bone scintigraphy both in lesion based analysis (98 vs. 53%, p=0.0015) and in patient based analysis (100 vs. 80%, p<0.001). Bone metastasis from HCC showed a high incidence of soft tissue formation requiring emergency treatment. Although the characteristic findings for soft tissue formation such as photon defect in bone scintigraphy are helpful in detection, overall detectability of bone metastasis is higher in FDG PET/CT. Contrast enhanced PET/CT will be useful in finding and delineating soft tissue forming bone metastasis from HCC.

High-resolution CT of temporal bone trauma: review of 38 cases

International Nuclear Information System (INIS)

Hiroual, M.R.; Zougarhi, A.; Cherif Idrissi El Ganouni, N.; Essadki, O.; Ousehal, A.; Tijani Adil, O.; Maliki, O.; Aderdour, L.; Raji, A.

2010-01-01

Purpose Temporal bone trauma is frequent but difficult to assess due to the diversity of clinical presentations and complex anatomy. We have sought to assess the different types of fractures and complications on high-resolution CT. Materials and methods Descriptive retrospective study over a 24 month period performed in the ENT radiology section of the Mohammed 6 university medical center in Marrakech. A total of 38 cases of temporal bone trauma were reviewed. All patients underwent ENT evaluation and high-resolution CT of the temporal bone using 1 mm axial and coronal sections. Results Mean patient age was 33 years (range: 14-55 years) with male predominance (sex ratio: 36/2). Clinical symptoms were mainly otorrhagia and conductive hearing loss. Oblique extra-labyrinthine fractures were most frequent. Two cases of pneumo-labyrinth were noted. Management was conservative in most cases with deafness in 3 cases. Conclusion High-resolution CT of the temporal bone provides accurate depiction of lesions explaining the clinical symptoms and helps guide management. MRI is complimentary to further assess the labyrinth and VII-VIII nerve complex. (author)

Conventional and CT angiography in children: dosimetry and dose comparisons

International Nuclear Information System (INIS)

Frush, Donald P.; Yoshizumi, Terry

2006-01-01

Tremendous advances have been made in imaging in children with both congenital and acquired heart disease. These include technical advances in cardiac catheterization and conventional angiography, especially with advancements in interventional procedures, as well as noninvasive imaging with MR and CT angiography. With rapid advances in multidetector CT (MDCT) technology, most recently 64-detector array systems (64-slice MDCT), have come a number of advantages over MR. However, both conventional and CT angiography impart radiation dose to children. Although the presence of radiation exposure to children has long been recognized, it is apparent that our ability to assess this dose, particularly in light of the rapid advancements, has been limited. Traditional methods of dosimetry for both conventional and CT angiography are somewhat cumbersome or involve a potential for substantial uncertainty. Recent developments in dosimetry, including metal oxide semiconductor field effect transistors (MOSFET) and the availability of anthropomorphic, tissue-equivalent phantoms have provided new opportunities for dosimetric assessments. Recent work with this technology in state-of-the-art cardiac angiography suites as well as with MDCT have offered direct comparisons of doses in infants and children undergoing diagnostic cardiac evaluation. It is with these dose data that assessment of risks, and ultimately the assessment of risk-benefit, can be better achieved. (orig.)

FDG-PET and CT patterns of bone metastases and their relationship to previously administered anti-cancer therapy

International Nuclear Information System (INIS)

Israel, Ora; Bar-Shalom, Rachel; Keidar, Zohar; Goldberg, Anat; Nachtigal, Alicia; Militianu, Daniela; Fogelman, Ignac

2006-01-01

To assess 18 F-fluorodeoxyglucose (FDG) uptake in bone metastases in patients with and without previous treatment, and compare positive positron emission tomography (PET) with osteolytic or osteoblastic changes on computed tomography (CT). One hundred and thirty-one FDG-PET/CT studies were reviewed for bone metastases. A total of 294 lesions were found in 76 patients, 81 in untreated patients and 213 in previously treated patients. PET was assessed for abnormal FDG uptake localised by PET/CT to the skeleton. CT was evaluated for bone metastases and for blastic or lytic pattern. The relationship between the presence and pattern of bone metastases on PET and CT, and prior treatment was statistically analysed using the chi-square test. PET identified 174 (59%) metastases, while CT detected 280 (95%). FDG-avid metastases included 74/81 (91%) untreated and 100/213 (47%) treated lesions (p<0.001). On CT there were 76/81 (94%) untreated and 204/213 (96%) treated metastases (p NS). In untreated patients, 85% of lesions were seen on both PET and CT (26 blastic, 43 lytic). In treated patients, 53% of lesions were seen only on CT (95 blastic, 18 lytic). Of the osteoblastic metastases, 65/174 (37%) were PET positive and 98/120 (82%), PET negative (p<0.001). The results of the present study indicate that when imaging bone metastases, prior treatment can alter the relationship between PET and CT findings. Most untreated bone metastases are PET positive and lytic on CT, while in previously treated patients most lesions are PET negative and blastic on CT. PET and CT therefore appear to be complementary in the assessment of bone metastases. (orig.)

Malignant bone tumors of the pelvis and of the extremities

International Nuclear Information System (INIS)

Gullotta, U.; Reiser, M.; Feuerbach, S.; Biehl, T.; Technische Univ. Muenchen

1981-01-01

Bone tumors of the extremities are usually diagnosed by conventional radiography. A good angiogram may render information not only about intra- and extraosseous extension of the tumor, but often also about the biological dignity. CT is usually not necessary, especially since it is sometimes difficult to define the extraosseous borders of these extremity tumors with this method. In bone tumors of the pelvis, however, neither conventional radiography nor angiography render reliable information about the extent of the tumor, which CT is very well able to do. Therefore CT is primarily indicated for evaluation of bone tumors in this region. Angiography is done only for preoperative evaluation of the vascular architecture or for potential therapeutic embolisation. (orig.) [de

Gadolinium-enhanced MR angiography of arterial occlusive disease in lower extremity : comparison with conventional digital subtraction angiography

International Nuclear Information System (INIS)

Shin, Sang June; Koh, Young Hwan; Cha, Joo Hee; Kim, Hyu Beom; Chung, Jin Wook; Park, Jae Hyung

2000-01-01

To compare the diagnostic value of gadolinium-enhanced MR angiography with that of conventional digital subtraction angiography for the evaluation of lower extremity arterial occlusive diseases. In 26 patients with symptomatic lower extremity arterial occlusive disease, both conventional digital subtraction angiography (DSA) and gadolinium-enhanced MR angiography (CE-MRA) were performed during the same week. MR angiography was performed using three-dimensional gradient-echo acquisition before, and two sequential acquisitions after, the administration of gadolinium (0.2 mmol/kg). In 23 patients, two separate, contiguous areas were scanned using additional doses. In three patients, only one field with a suspicious lesion was scanned. Three radiologists independently analyzed the CE-MRA and DSA findings of each vascular segment (20 segments per arterial tree) for the presence of obstructive lesions; the grade assigned was either mild or none (less than 50%), stenotic (50%-99%), or occlusion (100%). From among a total of 462 segments, DSA detected 99 which were significantly narrowed (stenosis, 33; occlusion, 66). Using MR angiography, 102 segments (stenosis 39; occlusion, 63) were identified, and 94 lesions (stenosis, 32; occlusion, 62) were graded correctly. Seven lesions were overestimated and four were underestimated. For the detection of hemodynamically significant stenosis or occlusions using MR angiography, sensitivity, specificity, and diagnostic accuracy were 95%, 98%, and 98% (G=3D0.995, P less than 0.001), respectively. To prove the absence of lesions, we repeated DSA in two patients with arterial spasm due to puncture. Three occluded segments seen on DSA, which revealed intact segments on MR angiography, suggested slow distal flow after reconstitution. For the evaluation of lower extremity arterial occlusive disease, the diagnostic value of gadolinium-enhanced MR angiography is comparable with that of digital subtraction angiography. The advantages of the

Agreement and precision of periprosthetic bone density measurements in micro-CT, single and dual energy CT.

Science.gov (United States)

Mussmann, Bo; Overgaard, Søren; Torfing, Trine; Traise, Peter; Gerke, Oke; Andersen, Poul Erik

2017-07-01

The objective of this study was to test the precision and agreement between bone mineral density measurements performed in micro CT, single and dual energy computed tomography, to determine how the keV level influences density measurements and to assess the usefulness of quantitative dual energy computed tomography as a research tool for longitudinal studies aiming to measure bone loss adjacent to total hip replacements. Samples from 10 fresh-frozen porcine femoral heads were placed in a Perspex phantom and computed tomography was performed with two acquisition modes. Bone mineral density was calculated and compared with measurements derived from micro CT. Repeated scans and dual measurements were performed in order to measure between- and within-scan precision. Mean density difference between micro CT and single energy computed tomography was 72 mg HA/cm 3 . For dual energy CT, the mean difference at 100 keV was 128 mg HA/cm 3 while the mean difference at 110-140 keV ranged from -84 to -67 mg HA/cm 3 compared with micro CT. Rescanning the samples resulted in a non-significant overall between-scan difference of 13 mg HA/cm 3 . Bland-Altman limits of agreement were wide and intraclass correlation coefficients ranged from 0.29 to 0.72, while 95% confidence intervals covered almost the full possible range. Repeating the density measurements for within-scan precision resulted in ICCs >0.99 and narrow limits of agreement. Single and dual energy quantitative CT showed excellent within-scan precision, but poor between-scan precision. No significant density differences were found in dual energy quantitative CT at keV-levels above 110 keV. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1470-1477, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Spectral K-edge subtraction imaging of experimental non-radioactive barium uptake in bone.

Science.gov (United States)

Panahifar, Arash; Samadi, Nazanin; Swanston, Treena M; Chapman, L Dean; Cooper, David M L

2016-12-01

To evaluate the feasibility of using non-radioactive barium as a bone tracer for detection with synchrotron spectral K-edge subtraction (SKES) technique. Male rats of 1-month old (i.e., developing skeleton) and 8-month old (i.e., skeletally mature) were orally dosed with low dose of barium chloride (33mg/kg/day Ba 2+ ) for 4weeks. The fore and hind limbs were dissected for imaging in projection and computed tomography modes at 100μm and 52μm pixel sizes. The SKES method utilizes a single bent Laue monochromator to prepare a 550eV energy spectrum to encompass the K-edge of barium (37.441keV), for collecting both 'above' and 'below' the K-edge data sets in a single scan. The SKES has a very good focal size, thus limits the 'crossover' and motion artifacts. In juvenile rats, barium was mostly incorporated in the areas of high bone turnover such as at the growth plate and the trabecular surfaces, but also in the cortical bone as the animals were growing at the time of tracer administration. However, the adults incorporated approximately half the concentration and mainly in the areas where bone remodeling was predominant and occasionally in the periosteal and endosteal layers of the diaphyseal cortical bone. The presented methodology is simple to implement and provides both structural and functional information, after labeling with barium, on bone micro-architecture and thus has great potential for in vivo imaging of pre-clinical animal models of musculoskeletal diseases to better understand their mechanisms and to evaluate the efficacy of pharmaceuticals. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Identification of genes differentially regulated in rat alveolar bone wound healing by subtractive hybridization.

Science.gov (United States)

Ohira, T; Myokai, F; Shiomi, N; Yamashiro, K; Yamamoto, T; Murayama, Y; Arai, H; Nishimura, F; Takashiba, S

2004-07-01

Periodontal healing requires the participation of regulatory molecules, cells, and scaffold or matrix. Here, we hypothesized that a certain set of genes is expressed in alveolar bone wound healing. Reciprocal subtraction gave 400 clones from the injured alveolar bone of Wistar rats. Identification of 34 genes and analysis of their expression in injured tissue revealed several clusters of unique gene regulation patterns, including the up-regulation at 1 wk of cytochrome c oxidase regulating electron transfer and energy metabolism, presumably occurring at the site of inflammation; up-regulation at 2.5 wks of pro-alpha-2 type I collagen involving the formation of a connective tissue structure; and up-regulation at 1 and 2 wks and down-regulation at 2.5 and 4 wks of ubiquitin carboxyl-terminal hydrolase l3 involving cell cycle, DNA repair, and stress response. The differential expression of genes may be associated with the processes of inflammation, wound contraction, and formation of a connective tissue structure.

Benign versus malignant osseous lesions in spine: differentiation by means of bone SPECT/CT fused image

International Nuclear Information System (INIS)

Yao Zhiming; Qu Wanying

2004-01-01

This study compared the efficiency of SPECT-CT fused image with planar bone scan, bone SPECT and CT in differentiating malignant from benign lesions and detecting metastases to the spine. Methods. Total 144 patients with spinal lesions underwent planar bone scan (WB), single photon tomography (SPECT), CT and SPECT-CT fused image by a SPECT/CT system. The malignant or benign nature of lesions was proved by radiological Methods, histological findings, 6-24 month follow-up, or all of these. The diagnostic results was divided into 4 types, i.e., normal, benign, doubtful malignant and malignant. Results. There were 137 malignant and 252 benign lesions in 144 patients, respectively. The percentages of doubtful malignant diagnosed by WB, SPECT, CT and fused image are 22.6%, 5.1%, 9.5% and 0%, respectively, p < 0.01-0.001, except for the comparison between the percentages of SPECT and CT. Sensitivities in detection of malignant lesions by WB, SPECT, CT and fused image are 75.2%, 94.2%, 96.6% and 99.3%, respectively, P < 0.001, excepting for the comparisons between those of SPECT and CT, and between those of CT and fused image. The sensitivities m detection of benign lesions by WB, SPECT, CT and fused image are, 56.7%, 86.5%, 90.1% and 96.8%, respectively, P < 0.005 - 0.001, excepting for the comparison between those of SPECT and CT. The specificities in detection of maliganant lesions by WB, SPECT, CT and fused image are 70.6%, 88.9%, 97.2% and 97.6%, respectively, P < 0.001, excepting for the comparison between those of CT and fused image. Conclusion. Bone SPECT-CT fused image has highest diagnostic and differentiating diagnostic values in detection of spinal abnormalities over the planar bone scanning and SPECT. The CT by present SPECT/CT system can complement planar bone scanning and SPECT and is clinically valuable in detection of spinal abnormalities. (authors)

Diagnostic yield and accuracy of CT angiography, MR angiography, and digital subtraction angiography for detection of macrovascular causes of intracerebral haemorrhage: Prospective, multicentre cohort study

NARCIS (Netherlands)

C.J.J. Van Asch (Charlotte J.J.); B.K. Velthuis (Birgitta K.); G.J.E. Rinkel (Gabriël J.E.); A. Algra (Ale); G.A.P. de Kort (G. A P); T.D. Witkamp (Theo); J.C.M. De Ridder (Johanna C.M.); K.M. Van Nieuwenhuizen (Koen M.); F.-E. De Leeuw (Frank-Erik); W.J. Schonewille (Wouter); P.L.M. de Kort (Paul); D.W.J. Dippel (Diederik); T.W.M. Raaymakers (Theodora W.M.); J. Hofmeijer; M.J.H. Wermer (Marieke); H. Kerkhoff (Henk); K. Jellema (Korné); I.M. Bronner (Irene M.); M.J.M. Remmers (Michel ); H.P. Bienfait (Henri); R.J.G.M. Witjes (Ron J.G.M.); J.P. Greving (Jacoba); C.J.M. Klijn (Catharina J.M.); H.F. de Leeuw (Frank); H.B. Boogaarts; E.J. van Dijk (Ewoud); W.J. Schonewille; W.M.J. Pellikaan; C. Puppels-De Waard; P.L.M. De Kort; J.P. Peluso; J. van Tuijl (Jordie); J. Hofmeijer; F.B.M. Joosten (Frank); D.W.J. Dippel (Diederik); L. Khajeh (Ladbon); T.W.M. Raaijmakers; M.J. Wermer; M.A.A. van Walderveen (Marianne); H. Kerkhoff; E. Zock; K. Jellema (Korné); G.J. Lycklama à Nijeholt (Geert); I.M. Bronner; M.J.M. Remmers; R.J.G.M. Witjes; H.P. Bienfait; K.E. Droogh-Greve; R. Donders (Rogier); V.I.H. Kwa; T.H.C.M.L. Schreuder (Tobien H. C. M. L.); C.L. Franke (Cees); J.S. Straver; C. Jansen; S.L.M. Bakker (Stef); C.C. Pleiter (C.); M.C. Visser; C.J.J. Van Asch; B.K. Velthuis (Birgitta); G.J.E. Rinkel (Gabriel); K.M. Van Nieuwenhuizen; C.J.M. Klijn (Catharina J.M.)

2015-01-01

textabstractStudy question What are the diagnostic yield and accuracy of early computed tomography (CT) angiography followed by magnetic resonance imaging/angiography (MRI/MRA) and digital subtraction angiography (DSA) in patients with non-traumatic intracerebral haemorrhage? Methods This

Establishing a method to measure bone structure using spectral CT

Science.gov (United States)

Ramyar, M.; Leary, C.; Raja, A.; Butler, A. P. H.; Woodfield, T. B. F.; Anderson, N. G.

2017-03-01

Combining bone structure and density measurement in 3D is required to assess site-specific fracture risk. Spectral molecular imaging can measure bone structure in relation to bone density by measuring macro and microstructure of bone in 3D. This study aimed to optimize spectral CT methodology to measure bone structure in excised bone samples. MARS CT with CdTe Medipix3RX detector was used in multiple energy bins to calibrate bone structure measurements. To calibrate thickness measurement, eight different thicknesses of Aluminium (Al) sheets were scanned one in air and the other around a falcon tube and then analysed. To test if trabecular thickness measurements differed depending on scan plane, a bone sample from sheep proximal tibia was scanned in two orthogonal directions. To assess the effect of air on thickness measurement, two parts of the same human femoral head were scanned in two conditions (in the air and in PBS). The results showed that the MARS scanner (with 90μm voxel size) is able to accurately measure the Al (in air) thicknesses over 200μm but it underestimates the thicknesses below 200μm because of partial volume effect in Al-air interface. The Al thickness measured in the highest energy bin is overestimated at Al-falcon tube interface. Bone scanning in two orthogonal directions gives the same trabecular thickness and air in the bone structure reduced measurement accuracy. We have established a bone structure assessment protocol on MARS scanner. The next step is to combine this with bone densitometry to assess bone strength.

Precision of DVC approaches for strain analysis in bone imaged with μCT at different dimensional levels.

Science.gov (United States)

Dall'Ara, Enrico; Peña-Fernández, Marta; Palanca, Marco; Giorgi, Mario; Cristofolini, Luca; Tozzi, Gianluca

2017-11-01

Accurate measurement of local strain in heterogeneous and anisotropic bone tissue is fundamental to understand the pathophysiology of musculoskeletal diseases, to evaluate the effect of interventions from preclinical studies, and to optimize the design and delivery of biomaterials. Digital volume correlation (DVC) can be used to measure the three-dimensional displacement and strain fields from micro-Computed Tomography (µCT) images of loaded specimens. However, this approach is affected by the quality of the input images, by the morphology and density of the tissue under investigation, by the correlation scheme, and by the operational parameters used in the computation. Therefore, for each application the precision of the method should be evaluated. In this paper we present the results collected from datasets analyzed in previous studies as well as new data from a recent experimental campaign for characterizing the relationship between the precision of two different DVC approaches and the spatial resolution of the outputs. Different bone structures scanned with laboratory source µCT or Synchrotron light µCT (SRµCT) were processed in zero-strain tests to evaluate the precision of the DVC methods as a function of the subvolume size that ranged from 8 to 2500 micrometers. The results confirmed that for every microstructure the precision of DVC improves for larger subvolume size, following power laws. However, for the first time large differences in the precision of both local and global DVC approaches have been highlighted when SRµCT or in vivo µCT images were used instead of conventional ex vivo µCT. These findings suggest that in situ mechanical testing protocols applied in SRµCT facilities should be optimized in order to allow DVC analyses of localized strain measurements. Moreover, for in vivo µCT applications DVC analyses should be performed only with relatively course spatial resolution for achieving a reasonable precision of the method. In conclusion

Bone marrow trephine biopsy in Hodgkin's lymphoma. Comparison with PET-CT scan in 65 patients.

Science.gov (United States)

Lakhwani, Sunil; Cabello-García, Dolores; Allende-Riera, Ana; Cárdenas-Negro, Carlos; Raya, José María; Hernández-Garcia, Miguel T

2018-02-09

To compare bone marrow biopsy (BMB) and PET/CT in detecting bone marrow involvement in Hodgkin's lymphoma MATERIAL AND METHODS: Retrospective analysis of 65 patients with both tests in the initial staging or in relapse with special attention to the PET/CT uptake pattern. In 3 patients (4.6%), the BMB showed bone marrow involvement with the PET/CT being positive in them all: 2 with diffuse+multifocal pattern and one diffuse only. In 11 additional patients (total 14/65, 21%), bone marrow involvement was diagnosed by PET/CT because bone marrow uptake was above hepatic one. The pattern was focal only in 2 cases, multifocal in 5, diffuse in 3 and diffuse+multifocal in one. In these last 4 cases the BMB showed an unspecific myelopathy. PET/CT detects all cases with BMB affected and many that escape to biopsy, however when the uptake pattern is diffuse it could be by involvement or reactive hyperplasia and in those cases the BMB should be done. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Comparative study of conducting iliac angioplasties with digital subtraction and conventional angiography. Incidence on true (consumable) costs

International Nuclear Information System (INIS)

Brenot, P.; Raynaud, A.; Pernes, J.M.; Parola, J.L.; Gaux, J.C.

1986-01-01

Differences in time and cost were evaluated between the performance of iliac angioplasty with conventional (AC) and digital subtraction (AN) angiography, after a total of 27 angioplasties (13 with AC and 14 with AN). Excluding amortization of material and personnel costs, findings confirmed a certain number of advantages for AN: gain in time of about 34%, decrease of about 14% in charges, and notably of 83% in expenditure on films and 50% on contrast media [fr

Fibrous dysplasia mimicking bone metastasis on both bone scintigraphy and {sup 18}F FDG PET CT: Diagnostic dilemma in a patient with breast cancer

Energy Technology Data Exchange (ETDEWEB)

KC, Sud Hir Suman; Sharma, Punit; Singh, Har Man Deep; Bal, Chand Rasekhar; Kumar, Rake Sh [India Institute of Medical Sciences, New Delhi (India)

2012-12-15

Bone is the most common distant site to which breast cancer metastasizes. Commonly used imaging modalities for imaging bone metastasis are bone scintigraphy, plain radiography, computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET). Although bone scintigraphy gas high sensitivity for detecting bone metastasis, its specificity is low. This is because of the fact that bone scintigraphy images secondary changes in bone rather than just tumor cells {sup 18}F fluorodeoxyglucose ({sup 18}F FDG) PET CT, on the other hand, directly images the tumor cells' glucose metabolism. Unfortunately, similar to bone scintigraphy, benign bone conditions can also show increased {sup 18}F FDG uptake on PET CT, and PET positive asymptomatic fibrous dysplasia can be misinterpreted as a metastasis. Fibrous dysplasia of bone has wide skeletal distribution, with variability of {sup 18}F FDG uptake and CT appearance. It is therefore important to recognize the characteristics of this skeletal dysplasia, to allow differentiation from skeletal metastasis. Bone lesions with {sup 18}F FDG uptake need to be carefully interpreted when evaluating patients with known malignancy. In doubtful cases, fibrous dysplasia should be given as a differential diagnosis and histopathological diagnosis may be warranted, as highlighted in the present case.

A Prospective Study Comparing 99mTc-Hydroxyethylene-Diphosphonate Planar Bone Scintigraphy and Whole-Body SPECT/CT with 18F-Fluoride PET/CT and 18F-Fluoride PET/MRI for Diagnosing Bone Metastases.

Science.gov (United States)

Löfgren, Johan; Mortensen, Jann; Rasmussen, Sine H; Madsen, Claus; Loft, Annika; Hansen, Adam E; Oturai, Peter; Jensen, Karl Erik; Mørk, Mette Louise; Reichkendler, Michala; Højgaard, Liselotte; Fischer, Barbara M

2017-11-01

We prospectively evaluated and compared the diagnostic performance of 99m Tc-hydroxyethylene-diphosphonate ( 99m Tc-HDP) planar bone scintigraphy (pBS), 99m Tc-HDP SPECT/CT, 18 F-NaF PET/CT, and 18 F-NaF PET/MRI for the detection of bone metastases. Methods: One hundred seventeen patients with histologically proven malignancy referred for clinical pBS were prospectively enrolled. pBS and whole-body SPECT/CT were performed followed by 18 F-NaF PET/CT within 9 d. 18 F-NaF PET/MRI was also performed in 46 patients. Results: Bone metastases were confirmed in 16 patients and excluded in 101, which was lower than expected. The number of equivocal scans was significantly higher for pBS than for SPECT/CT and PET/CT (18 vs. 5 and 6, respectively; P = 0.004 and 0.01, respectively). When equivocal readings were excluded, no statistically significant difference in sensitivity, specificity, positive predictive value, negative predictive value, or overall accuracy were found when comparing the different imaging techniques. In the per-patient analysis, equivocal scans were either assumed positive for metastases ("pessimistic analysis") or assumed negative for metastases ("optimistic analysis"). The percentages of misdiagnosed patients for the pessimistic analysis were 21%, 15%, 9%, and 7% for pBS, SPECT/CT, PET/CT, and PET/MRI, respectively. Corresponding figures for the optimistic analysis were 9%, 12%, 5%, and 7%. In those patients identified as having bone metastases according to the reference standard, SPECT/CT, 18 F-NaF PET/CT, and PET/MRI detected additional lesions compared with pBS in 31%, 63%, and 71%, respectively. Conclusion: 18 F-NaF PET/CT and whole-body SPECT/CT resulted in a significant reduction of equivocal readings compared with pBS, which implies an improved diagnostic confidence. However, the clinical benefit of using, for example, 18 F-NaF PET/CT or PET/MRI as compared with SPECT/CT and pBS in this patient population with a relatively low prevalence of bone

Intraoperative cone-beam computed tomography and multi-slice computed tomography in temporal bone imaging for surgical treatment.

Science.gov (United States)

Erovic, Boban M; Chan, Harley H L; Daly, Michael J; Pothier, David D; Yu, Eugene; Coulson, Chris; Lai, Philip; Irish, Jonathan C

2014-01-01

Conventional computed tomography (CT) imaging is the standard imaging technique for temporal bone diseases, whereas cone-beam CT (CBCT) imaging is a very fast imaging tool with a significant less radiation dose compared with conventional CT. We hypothesize that a system for intraoperative cone-beam CT provides comparable image quality to diagnostic CT for identifying temporal bone anatomical landmarks in cadaveric specimens. Cross-sectional study. University tertiary care facility. Twenty cadaveric temporal bones were affixed into a head phantom and scanned with both a prototype cone-beam CT C-arm and multislice helical CT. Imaging performance was evaluated by 3 otologic surgeons and 1 head and neck radiologist. Participants were presented images in a randomized order and completed landmark identification questionnaires covering 21 structures. CBCT and multislice CT have comparable performance in identifying temporal structures. Three otologic surgeons indicated that CBCT provided statistically equivalent performance for 19 of 21 landmarks, with CBCT superior to CT for the chorda tympani and inferior for the crura of the stapes. Subgroup analysis showed that CBCT performed superiorly for temporal bone structures compared with CT. The radiologist rated CBCT and CT as statistically equivalent for 18 of 21 landmarks, with CT superior to CBCT for the crura of stapes, chorda tympani, and sigmoid sinus. CBCT provides comparable image quality to conventional CT for temporal bone anatomical sites in cadaveric specimens. Clinical applications of low-dose CBCT imaging in surgical planning, intraoperative guidance, and postoperative assessment are promising but require further investigation.

Computed Tomography (CT) -- Sinuses

Medline Plus

Full Text Available ... quickly. When you enter the CT scanner, special light lines may be seen projected onto your body, ... its ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional ...

Computed Tomography (CT) -- Head

Medline Plus

Full Text Available ... quickly. When you enter the CT scanner, special light lines may be seen projected onto your body, ... its ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional ...

Scaphoid fracture: Bone marrow edema detected with dual-energy CT virtual non-calcium images and confirmed with MRI

Energy Technology Data Exchange (ETDEWEB)

Dareez, Nazeer M.; Engesland, Eirin; Lindland, Elisabeth S. [Department of Radiology, SSHF Arendal, Arendal (Norway); Dahlslett, Kristine H. [Haukelands Universitetssjukehus, Department of Radiology, Bergen (Norway)

2017-12-15

We aimed to determine whether bone marrow edema (BME) in acute traumatic scaphoid fracture could be demonstrated with dual-energy CT (DECT) using MRI as the gold standard. In recent years, virtual non-calcium (VNCa) images have been used to demonstrate BME in trauma cases, for example, in vertebral compression fractures, hip trauma to detect occult fractures and knee fractures. We present three cases of acute scaphoid trauma. Two patients had subtle or invisible fractures on x-ray and conventional CT images, while DECT VNCa images clearly visualized the BME, which was confirmed by MRI. One patient had negative findings on both VNCa and MRI images. The DECT VNCa algorithm is a promising technique to demonstrate BME in scaphoid fractures, with potential for increasing the diagnostic value of CT in this type of injury. (orig.)

Suppression of high-density artefacts in x-ray CT images using temporal digital subtraction with application to cryotherapy

Energy Technology Data Exchange (ETDEWEB)

Baissalov, R.; Sandison, G.A.; Rewcastle, J.C. [Department of Medical Physics, Tom Baker Cancer Center, Calgary, Canada, T2N 4N2 2 Department of Physics and Astronomy, University of Calgary, Calgary T2N 2N4 (Canada); Donnelly, B.J. [Department of Surgery, Tom Baker Cancer Center, Calgary, Canada, T2N 4N2 4 Department of Surgery, Foothills Hospital, Calgary T2N 2T7 (Canada); Saliken, J.C. [Department of Surgery, Tom Baker Cancer Center, Calgary T2N 4N2 (Canada); Department of Diagnostic Imaging, Foothills Hospital, Calgary T2N 2T7 (Canada); McKinnon, J.G. [Department of Surgery, Foothills Hospital, Calgary T2N 2T7 (Canada); Muldrew, K. [Department of Surgery, Faculty of Medicine, University of Calgary, Calgary T2N 2T7 (Canada)

2000-05-01

Image guidance in cryotherapy is usually performed using ultrasound. Although not currently in routine clinical use, x-ray CT imaging is an alternative means of guidance that can display the full 3D structure of the iceball, including frozen and unfrozen regions. However, the quality of x-ray CT images is compromised by the presence of high-density streak artefacts. To suppress these artefacts we applied temporal digital subtraction (TDS). This TDS method has the added advantage of improving the grey-scale contrast between frozen and unfrozen tissue in the CT images. Two sets of CT images were taken of a phantom material, cryoprobes and a urethral warmer (UW) before and during the cryoprobe freeze cycle. The high-density artefacts persisted in both image sets. TDS was performed on these two image sets using the corresponding mask image of unfrozen material and the same geometrical configuration of the cryoprobes and the UW. The resultant difference image had a significantly reduced artefact content. Thus TDS can be used to significantly suppress or eliminate high-density CT streak artefacts without reducing the metallic content of the cryoprobes. In vivo study needs to be conducted to establish the utility of this TDS procedure for CT assisted prostate or liver cryotherapy. Applying TDS in x-ray CT guided cryotherapy will facilitate estimation of the number and location of all frozen and unfrozen regions, potentially making cryotherapy safer and less operator dependent. (author)

Suppression of high-density artefacts in x-ray CT images using temporal digital subtraction with application to cryotherapy

International Nuclear Information System (INIS)

Baissalov, R.; Sandison, G.A.; Rewcastle, J.C.; Donnelly, B.J.; Saliken, J.C.; McKinnon, J.G.; Muldrew, K.

2000-01-01

Image guidance in cryotherapy is usually performed using ultrasound. Although not currently in routine clinical use, x-ray CT imaging is an alternative means of guidance that can display the full 3D structure of the iceball, including frozen and unfrozen regions. However, the quality of x-ray CT images is compromised by the presence of high-density streak artefacts. To suppress these artefacts we applied temporal digital subtraction (TDS). This TDS method has the added advantage of improving the grey-scale contrast between frozen and unfrozen tissue in the CT images. Two sets of CT images were taken of a phantom material, cryoprobes and a urethral warmer (UW) before and during the cryoprobe freeze cycle. The high-density artefacts persisted in both image sets. TDS was performed on these two image sets using the corresponding mask image of unfrozen material and the same geometrical configuration of the cryoprobes and the UW. The resultant difference image had a significantly reduced artefact content. Thus TDS can be used to significantly suppress or eliminate high-density CT streak artefacts without reducing the metallic content of the cryoprobes. In vivo study needs to be conducted to establish the utility of this TDS procedure for CT assisted prostate or liver cryotherapy. Applying TDS in x-ray CT guided cryotherapy will facilitate estimation of the number and location of all frozen and unfrozen regions, potentially making cryotherapy safer and less operator dependent. (author)

Spectral amplitude coding OCDMA using and subtraction technique.

Science.gov (United States)

Hasoon, Feras N; Aljunid, S A; Samad, M D A; Abdullah, Mohamad Khazani; Shaari, Sahbudin

2008-03-20

An optical decoding technique is proposed for a spectral-amplitude-coding-optical code division multiple access, namely, the AND subtraction technique. The theory is being elaborated and experimental results have been done by comparing a double-weight code against the existing code, Hadamard. We have proved that the and subtraction technique gives better bit error rate performance than the conventional complementary subtraction technique against the received power level.

Can FDG-PET/CT replace blind bone marrow biopsy of the posterior iliac crest in Ewing sarcoma?

International Nuclear Information System (INIS)

Kasalak, Oemer; Glaudemans, Andor W.J.M.; Overbosch, Jelle; Kwee, Thomas C.; Jutte, Paul C.

2018-01-01

To determine and compare the value of 18 F-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (FDG-PET/CT) to blind bone marrow biopsy (BMB) of the posterior iliac crest in detecting metastatic bone marrow involvement in newly diagnosed Ewing sarcoma. This retrospective study included 20 patients with newly diagnosed Ewing sarcoma who underwent pretreatment FDG-PET/CT and a total of 38 blind BMBs (two unilateral and 18 bilateral) of the posterior iliac crest. FDG-PET/CT scans were evaluated for bone marrow involvement, both in the posterior iliac crest and other sites, and compared to blind BMB results. FDG-PET/CT was positive for bone marrow involvement in 7/38 posterior iliac crests, whereas BMB was positive in 5/38 posterior iliac crests. FDG-PET/CT and BMB results in the posterior iliac crest agreed in 36/38 cases (94.7%, 95% confidence interval [CI]: 82.7-98.5%). On a patient level, FDG-PET/CT was positive for bone marrow involvement in 4/20 patients, whereas BMB of the posterior iliac crest was positive in 3/20 patients. On a patient level, FDG-PET/CT and BMB results agreed in 19/20 patients (95.0%, 95% CI: 76.4-99.1%). The only discrepancies between FDG-PET/CT and BMB were observed in two BMBs of one patient. Both BMBs in this patient were negative, whereas FDG-PET/CT indicated bilateral posterior iliac crest involvement and also extensive bone marrow involvement elsewhere. FDG-PET/CT appears to be a valuable method for metastatic bone marrow assessment in newly diagnosed Ewing sarcoma. The routine use of blind BMB of the posterior iliac crest should be reconsidered when FDG-PET/CT is available. (orig.)

Can FDG-PET/CT replace blind bone marrow biopsy of the posterior iliac crest in Ewing sarcoma?

Energy Technology Data Exchange (ETDEWEB)

Kasalak, Oemer; Glaudemans, Andor W.J.M.; Overbosch, Jelle; Kwee, Thomas C. [University of Groningen, Department of Radiology, Nuclear Medicine and Molecular Imaging, University Medical Center Groningen (Netherlands); Jutte, Paul C. [University of Groningen, Department of Orthopedics, University Medical Center Groningen (Netherlands)

2018-03-15

To determine and compare the value of {sup 18}F-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (FDG-PET/CT) to blind bone marrow biopsy (BMB) of the posterior iliac crest in detecting metastatic bone marrow involvement in newly diagnosed Ewing sarcoma. This retrospective study included 20 patients with newly diagnosed Ewing sarcoma who underwent pretreatment FDG-PET/CT and a total of 38 blind BMBs (two unilateral and 18 bilateral) of the posterior iliac crest. FDG-PET/CT scans were evaluated for bone marrow involvement, both in the posterior iliac crest and other sites, and compared to blind BMB results. FDG-PET/CT was positive for bone marrow involvement in 7/38 posterior iliac crests, whereas BMB was positive in 5/38 posterior iliac crests. FDG-PET/CT and BMB results in the posterior iliac crest agreed in 36/38 cases (94.7%, 95% confidence interval [CI]: 82.7-98.5%). On a patient level, FDG-PET/CT was positive for bone marrow involvement in 4/20 patients, whereas BMB of the posterior iliac crest was positive in 3/20 patients. On a patient level, FDG-PET/CT and BMB results agreed in 19/20 patients (95.0%, 95% CI: 76.4-99.1%). The only discrepancies between FDG-PET/CT and BMB were observed in two BMBs of one patient. Both BMBs in this patient were negative, whereas FDG-PET/CT indicated bilateral posterior iliac crest involvement and also extensive bone marrow involvement elsewhere. FDG-PET/CT appears to be a valuable method for metastatic bone marrow assessment in newly diagnosed Ewing sarcoma. The routine use of blind BMB of the posterior iliac crest should be reconsidered when FDG-PET/CT is available. (orig.)

CT-MR image data fusion for computer assisted navigated neurosurgery of temporal bone tumors

International Nuclear Information System (INIS)

Nemec, Stefan Franz; Donat, Markus Alexander; Mehrain, Sheida; Friedrich, Klaus; Krestan, Christian; Matula, Christian; Imhof, Herwig; Czerny, Christian

2007-01-01

Purpose: To demonstrate the value of multi detector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the preoperative work up of temporal bone tumors and to present, especially, CT and MR image fusion for surgical planning and performance in computer assisted navigated neurosurgery of temporal bone tumors. Materials and methods: Fifteen patients with temporal bone tumors underwent MDCT and MRI. MDCT was performed in high-resolution bone window level setting in axial plane. The reconstructed MDCT slice thickness was 0.8 mm. MRI was performed in axial and coronal plane with T2-weighted fast spin-echo (FSE) sequences, un-enhanced and contrast-enhanced T1-weighted spin-echo (SE) sequences, and coronal T1-weighted SE sequences with fat suppression and with 3D T1-weighted gradient-echo (GE) contrast-enhanced sequences in axial plane. The 3D T1-weighted GE sequence had a slice thickness of 1 mm. Image data sets of CT and 3D T1-weighted GE sequences were merged utilizing a workstation to create CT-MR fusion images. MDCT and MR images were separately used to depict and characterize lesions. The fusion images were utilized for interventional planning and intraoperative image guidance. The intraoperative accuracy of the navigation unit was measured, defined as the deviation between the same landmark in the navigation image and the patient. Results: Tumorous lesions of bone and soft tissue were well delineated and characterized by CT and MR images. The images played a crucial role in the differentiation of benign and malignant pathologies, which consisted of 13 benign and 2 malignant tumors. The CT-MR fusion images supported the surgeon in preoperative planning and improved surgical performance. The mean intraoperative accuracy of the navigation system was 1.25 mm. Conclusion: CT and MRI are essential in the preoperative work up of temporal bone tumors. CT-MR image data fusion presents an accurate tool for planning the correct surgical procedure and is a

Pre-operative evaluation of cleft palate using three dimensional computerized tomography (s-D CT)

International Nuclear Information System (INIS)

Azia, A.; Hashmi, R.

1999-01-01

Cleft palate is a congenital anomaly with major development concerns. Surgery with bone grafting is often required to correct the lesion. With the introduction of 3-D CT the evaluation of cleft pa late has become more accurate. We present two cases of cleft palate, which were operated upon with bone grafting. We employed 3-D CT techniques in addition to the conventional 2-D CT, 3-D CT improves the estimation of the required bone graft and signification reduces length of surgery and complications. (author)

Evaluation of sacroiliitis: contrast-enhanced MRI with subtraction technique

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Algin, Oktay; Gokalp, Gokhan; Baran, Bulent; Ocakoglu, Gokhan; Yazici, Zeynep [Uludag University, Medical Faculty, Department of Radiology, Gorukle, Bursa (Turkey)

2009-10-15

The purpose of the study was to investigate the diagnostic value of contrast-enhanced MRI using the subtraction technique in the detection of active sacroiliitis. Magnetic resonance imaging was performed in 8 asymptomatic volunteers and 50 patients with clinically suspected active sacroiliitis. On precontrast MR images, T1-weighted spin-echo images with and without fat saturation (T1WFS and T1W), STIR and 3D-FLASH images with fat saturation were obtained in the semicoronal plane using a 1.5 Tesla imager. Postcontrast MRI was performed using the same T1WFS sequence as before contrast injection for all volunteers and patients. Postcontrast images were subtracted from fat-suppressed precontrast images. Enhancement within the joint space and bone marrow was considered to demonstrate active sacroiliitis. In 50 patients (100 sacroiliac joints [SIJs]), 40 (76 SIJs) were considered to have active sacroiliitis based on MR images. Bone marrow edema was present in 33 patients (62 SIJs) on STIR images. Routine MRI allowed identification of contrast enhancement in SIJs on postcontrast T1WFS images in 31 patients (49 SIJs). Contrast enhancement was observed in 40 patients (76 SIJs) who were examined by MRI using the subtraction technique. Contrast enhancement was significantly more conspicuous on subtraction images than on non-subtracted postcontrast T1WFS images (Mann-Whitney U test, p<0.001). Contrast-enhanced MRI with subtraction technique may be useful for early detection of active sacroiliitis. (orig.)

Digital subtraction cardiopulmonary angiography using FCR (Fuji computed radiography)

International Nuclear Information System (INIS)

Tanimura, Shigeo; Tomoyasu, Hiroshi; Banba, Jiro; Masaki, Mikio; Kanno, Yukio; Abe, Kazuo

1987-01-01

Digital subtraction cardiopulmonary angiography using FCR was performed on 46 patients including lung cancer, mediastinal tumor, giant bullous formation and others. The images of digital subtraction for pulmonary artery, pulmonary vein and thoracic aorta were studied by comparing to the conventional pulmonary angiogram. Good images of pulmonary artery due to digital subtraction were obtained in 80 % of the 45 cases. This method needed only half volume of contrast media compared to the conventional for obtaining good images and thus reduced side effect. Therefore this method seems to be an usefull pre-operative examination in various chest diseases, especially in case of lung cancer. (author)

Dual-time-point FDG-PET/CT Imaging of Temporal Bone Chondroblastoma: A Report of Two Cases

Directory of Open Access Journals (Sweden)

Akira Toriihara

2015-07-01

Full Text Available Temporal bone chondroblastoma is an extremely rare benign bone tumor. We encountered two cases showing similar imaging findings on computed tomography (CT, magnetic resonance imaging (MRI, and dual-time-point 18F-fluorodeoxyglucose (18F-FDG positron emission tomography (PET/CT. In both cases, CT images revealed temporal bone defects and sclerotic changes around the tumor. Most parts of the tumor showed low signal intensity on T2- weighted MRI images and non-uniform enhancement on gadolinium contrast-enhanced T1-weighted images. No increase in signal intensity was noted in diffusion-weighted images. Dual-time-point PET/CT showed markedly elevated 18F-FDG uptake, which increased from the early to delayed phase. Nevertheless, immunohistochemical analysis of the resected tumor tissue revealed weak expression of glucose transporter-1 and hexokinase II in both tumors. Temporal bone tumors, showing markedly elevated 18F-FDG uptake, which increases from the early to delayed phase on PET/CT images, may be diagnosed as malignant bone tumors. Therefore, the differential diagnosis should include chondroblastoma in combination with its characteristic findings on CT and MRI.

Digital subtraction angiography system evaluation with phantoms

International Nuclear Information System (INIS)

Wenstrup, R.S.; Sweeney, K.P.; Scholz, F.J.

1985-01-01

Advances in digital subtraction angiography imaging demonstrate the need for critical evaluation of the performance of digital subtraction equipment. The design of a phantom set for noninvasive assessment of the imaging quality of digital subtraction equipment is described; components include a remotely controlled transport system and individual patterns to evaluate the contrast and detail properties of the image intensifier, low-contrast sensitivity and resolution of the system, geometric distortion of image, linearity, mechanical and electronic stability of equipment, and effects of bone and bowel gas on iodine perception. The performance of an add-on digital radiographic system is presented, along with radiation exposure levels at the image intensifier for a range of radiographic techniques

[sup 99m]Tc-RBC subtraction scintigraphy; Assessmet of bleeding site and rate

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Inagaki, Syoichi; Tonami, Syuichi; Yasui, Masakazu; Kuranishi, Makoto; Sugishita, Kouki; Nakamura, Mamoru (Toyama Medical and Pharmaceutical Univ. (Japan). Hospital)

1994-03-01

Sequential abdominal scintigrams with [sup 99m]Tc-labelled red blood cells (RBC) were subtracted for observing a site of gastrointestinal bleeding and calculating the bleeding rate. This method is technically very easy and can detect the site of bleeding with the minimum rate, as low as 0.2 ml/min., in a phantom experiment. In 23 cases with final diagnosis of gastrointestinal bleeding, conventional non-subtraction scintigraphy detected only 30% (7/23), but subtraction scintigraphy detected 61% (14/23). It was concluded that subtraction scintigraphy had higher sensitivity than conventional scintigraphy for early diagnosing bleeding. A combination of non-subtraction and subtraction scintigraphy is recommended to detect a site of gastrointestinal bleeding in a clinical setting. (author).

Evaluation of Efficacy of Bone Scan With SPECT/CT in the Management of Low Back Pain: A Study Supported by Differential Diagnostic Local Anesthetic Blocks.

Science.gov (United States)

Jain, Anuj; Jain, Suruchi; Agarwal, Anil; Gambhir, Sanjay; Shamshery, Chetna; Agarwal, Amita

2015-12-01

Conventional radiologic modalities provide details only about the anatomic aspect of the various structures of the spine. Frequently the structures that show abnormal morphology may not be the cause of low back pain (LBP). Functional imaging in the form of bone scan along with single photon emission computerized tomography (SPECT/CT) may be helpful in identifying structures causing pain, whether morphologically normal or not. The objective of this study is to evaluate the role of bone scan with SPECT/CT in management of patients with LBP. This is randomized double-blinded controlled study performed on 80 patients with LBP aged 20 to 80 years, ASA physical status I to III. Patients were randomized into bone scan and control groups consisting of 40 patients each. On the basis of the clinical features and radiologic findings a clinical diagnosis was made. After making a clinical diagnosis, the patients in bone scan group were subjected to bone scan with SPECT/CT. On the basis of the finding of the bone scan and SPECT/CT, a new working diagnosis was made and intervention was performed according to the new working diagnosis. Diagnostic blocks in the control group were given based on clinical diagnosis. Controlled comparative diagnostic blocks were performed with local anesthetic. The pain score just after the diagnostic block and at the time of discharge (approximately 4 h later) was recorded; the pain relief was recorded in percentage. In both the groups, sacroilitis was the most common diagnosis followed by facet joint arthropathy. The number of patients obtaining pain relief of >50% was significantly higher in the bone scan-positive group as compared with the control group. Three new clinical conditions were identified in the bone scan group. These conditions were multiple myeloma, avascular necrosis of the femoral head, and ankylosing spondylitis. Bone scan with SPECT/CT was found to complement the clinical workup of patients with LBP. Inclusion of bone scan with

CT of temporal bone - IV. inner ear

International Nuclear Information System (INIS)

Kwon, Jae Yoon; Sung, Kyu Bo; Youn, Eun Kyoung; Park, Youn Kyeung; Lee, Young Uk

1990-01-01

Temporal bone CT was done in 697 patients from April 1985 to October 1989. The abnormal findings were seen in 453 patients, which were chronic otitis media in 355 patients, fracture in 49 patients and congenital anomaly in 44 patients, etc. The abnormal findings of inner ear were observed on 46 patients. The results were summarized as follows : 1. The incidence of inner ear involvement by chronic otitis media was 7.3% (26/355 : labyrinthine fistula in 17 patients, labyrinthitis ossificans in 9 patients). Labyrinthine fistula was most commonly located on lateral semicircular canal (15/17, 88.2%). 2. Fusion of vestibule with lateral semicircular canal and formation of common cavity was demonstrated incidentally in 5 patients (0.7% of total number of temporal bone CT), and bilateral in 3 patients. 3. The incidence of inner ear anomaly in congenital ear anomaly was 11.4% (5/44). All cases were bilateral and three patients showed associated middle ear anomaly. 4. The incidence of involvement of bony labyrinth in temporal bone fracture was 10.2% (5/49). Labyrinthine fracture was seen all patients of transverse(3) and mixed fracture(1). In longitudinal fracture, labyrinthine fracture was seen in 2.2% (1/45). 5. Others were traumatic labyrinthitis ossificans(1), intracanalicular acoustic neuroma(3) and facial nerve neuroma(1)

The value of spiral CT scan on fracture of ankle joint and tarsal bones

International Nuclear Information System (INIS)

Li Zhaoli; Liang Jingyin; Pan Zhifeng

2009-01-01

Objective: To study the value of spiral CT scan on the fracture of ankle joint and tarsal bones. Methods: 43 cases with the fracture of ankle joint and tarsal bones were collected and analyzed. All the cases were examined by plain film radiography and spiral CT thin slice scan. Multi-planar reformation (MPR), surface shaded display (SSD) and other techniques of image post-processing were performed in 35 cases of them. Results: Spiral CT scan could demonstrate more fractures than plain film radiography in 28 cases(65.1%). There are 15 cases (34.9%) which are normal in plain film radiography but abnormal in Spiral CT scan. Spiral CT could demonstrate the different length, width, direction and number of linear low density shadow. SSD and MPR were performed again in the cases with avulsion fracture and fragmental fracture to demonstrate the fracture direction and the shape, size and location of fragments more clearly. Conclusion: Spiral CT thin slice scan with image post-processing techniques can play an important role in fracture of ankle joint and tarsal bones. (authors)

Influence of metal artifacts on in vivo micro-CT for orthodontic mini-implants

International Nuclear Information System (INIS)

Ejima, Ken-ichiro; Omasa, Saori; Motoyoshi, Mitsuru; Arai, Yoshinori; Kai, Yukiko; Amemiya, Toshihiko; Yamada, Hisaya; Honda, Kazuya; Shimizu, Noriyoshi

2012-01-01

This study aimed to show the effects of metal artifacts on the in vivo micro-CT of mini-implants by measuring bone volume. We drilled a hole in the cortical bone of a rat tibia and embedded a titanium orthodontic mini-implant (diameter, 1.5 mm) in the hole. Twelve individually weighed hydroxyapatite grains (HA grains) were placed around the implant either by one dentist (method 1) or separately by 12 dentists (method 2). In vivo micro-CT was used to scan the model after placement of each grain to measure increases and decreases in bone volume voxel number. The subtracted bone voxel volume increased with HA weight in both methods. Simple linear regression analysis showed a significant correlation between weight and volume in both methods (method 1: regression coefficient: 516.502, P<0.05; method 2: regression coefficient: 4837.432, P<0.05). Metal artifacts did not appear to influence measurements of bone volume, although further studies are required to determine the effect of thicker implants. (author)

Self-masking subtraction tomosynthesis

International Nuclear Information System (INIS)

Chakraborty, D.P.; Yester, M.V.; Barnes, G.T.; Lakshminarayanan, A.V.

1984-01-01

The authors tested the image quality and dose savings of self-masking subtraction tomosynthesis (SST), which combines digital tomosynthesis with subtraction of a blurred self-mask. High-quality images of the inner ear of a head phantom were obtained at moderate dose savings. Although they were taken with linear motion, they did not exhibit the streaking due to off-fulcrum objects that is characteristic of conventional linear tomography. SST could reduce patient dose by a factor of at least 12 in examinations of the inner ear, and the mechanical aspects can be implemented with moderate modifications of existing instrumentation

Diagnostic performance of 11C-choline PET/CT and bone scintigraphy in the detection of bone metastases in patients with prostate cancer.

Science.gov (United States)

Kitajima, Kazuhiro; Fukushima, Kazuhito; Yamamoto, Shingo; Kato, Takashi; Odawara, Soichi; Takaki, Haruyuki; Fujiwara, Masayuki; Yamakado, Koichiro; Nakanishi, Yukako; Kanematsu, Akihiro; Nojima, Michio; Hirota, Shozo

2017-08-01

The aim of this study was to compare 11C-choline PET/CT and bone scintigraphy (BS) for detection of bone metastases in patients with prostate cancer. Twenty-one patients with histologically proven prostate cancer underwent 11C-choline PET/CT and BS before (n = 4) or after (n = 17) treatment. Patient-, region-, and lesion-based diagnostic performances of bone metastasis of both 11C-choline PET/CT and BS were evaluated using a five-point scale by two experienced readers. Bone metastases were present in 11 (52.4%) of 21 patients and 48 (32.7%) of 147 regions; 111 lesions were found to have bone metastases. Region-based analysis showed that the sensitivity, specificity, accuracy, and area under the receiver-operating-characteristic curves (AUC) of 11C-choline PET/CT were 97.9%, 99.0%, 98.6%, and 0.9989, respectively; those of BS were 72.9%, 99.0%, 90.5%, and 0.8386, respectively. Sensitivity, accuracy, and AUC significantly differed between the two methods (McNemar test, p = 0.0015, p = 0.0015, and p PET/CT detected 110/111 metastatic lesions (99.1%); BS detected 85 (76.6%) (p PET/BS were 100%/90.3% for the blastic type, 91.7%/8.3% for the lytic type, 100%/100% for the mixed type, and 100%/53.3% for the invisible type, respectively. Significant differences in blastic, lytic, and invisible types were observed between the two methods (p = 0.013, p = 0.0044, and p = 0.023, respectively). In conclusion, 11C-choline PET/CT had greater sensitivity and accuracy than BS for detection of bone involvement in patients with prostate cancer.

Anatomic and Quantitative Temporal Bone CT for Preoperative Assessment of Branchio-Oto-Renal Syndrome.

Science.gov (United States)

Ginat, D T; Ferro, L; Gluth, M B

2016-12-01

We describe the temporal bone computed tomography (CT) findings of an unusual case of branchio-oto-renal syndrome with ectopic ossicles that are partially located in the middle cranial fossa. We also describe quantitative temporal bone CT assessment pertaining to cochlear implantation in the setting of anomalous cochlear anatomy associated with this syndrome.

Normal lumbar spine bone mineral densities with single-energy CT

International Nuclear Information System (INIS)

Hendrick, R.E.; Ritenour, E.R.; Geis, J.R.; Thickman, D.; Freeman, K.

1988-01-01

The authors report trabecular spine densities determined by single-energy CT in 267 healthy women, aged 22 to 75 years. Volunteers were scanned at eight sites with use of identical fourth-generation CT scanners, postpatient calibration phantoms, and analysis software that accounts for beam hardening as a function of patient size. Results indicate that a cubic polynomial best represents the decrease in bone density (in milligrams per milliliter of K 2 HPO 4 ) with age (in years): Bone Density = 140.9 + 4.44(Age) - 0.133(Age) 2 + 0.0008(Age) 3 , with statistical significance over the best linear and quadratic polynomial fits (P < .001). The mean bone densities of healthy women above age 30 years are found to be lower by an average of 8 mg/mL than reported by Cann et al, whose data indicate that the greatest loss in trabecular bone density in healthy women occurs in the 50-59-year group, while out data indicate greatest loss in the 60-75 year age group

Mikro-CT: Technology and applications for assessing bone structure

International Nuclear Information System (INIS)

Engelke, K.; Karolczak, M.; Lutz, A.; Seibert, U.; Schaller, S.; Kalender, W.

1999-01-01

The strength and fracture resistance of bone is determined by the structure of the trabecular network and the cortical shell. While standard 2D techniques like histomorphometry are inadequate to assess the 3D nature of the trabecular network, isotropic 3D datasets of this network can be acquired with the new imaging modality of μCT. However, so far the quantitative analysis of the generated datasets, in particular the extraction of appropriate parameters describing the bone structure, has not been finally solved. In this article we describe the technology and applications of μCT systems relevant in the field of osteology. The most important technical features of current μCT systems in this context are: 1. A spatial resolution down to 5-10 μm can be achieved. 2. The maximum sample size is related to the desired resolution by a factor of approximately 1000, that is, a resolution of 10 μm limits the maximum sample size to approximately 1 cm. 3. Scan times for μCT systems vary between minutes and hours. Currently five areas for the application of μCT systems in osteology can be identified: 1. The search of parameters characterizing the 3D trabecular structure. 2. The application of finite element models to determine the biochemical competence of the structural parameters. 3. The use of μCT in preclinical trials to study drug effects in small animals. 4. The validation of analysis methods used in high-resolution in-vivo imaging systems. 5. The 3D quantification of modeling and remodeling processes. (orig.) [de

Bone volume fraction and structural parameters for estimation of mechanical stiffness and failure load of human cancellous bone samples; in-vitro comparison of ultrasound transit time spectroscopy and X-ray μCT.

Science.gov (United States)

Alomari, Ali Hamed; Wille, Marie-Luise; Langton, Christian M

2018-02-01

Conventional mechanical testing is the 'gold standard' for assessing the stiffness (N mm -1 ) and strength (MPa) of bone, although it is not applicable in-vivo since it is inherently invasive and destructive. The mechanical integrity of a bone is determined by its quantity and quality; being related primarily to bone density and structure respectively. Several non-destructive, non-invasive, in-vivo techniques have been developed and clinically implemented to estimate bone density, both areal (dual-energy X-ray absorptiometry (DXA)) and volumetric (quantitative computed tomography (QCT)). Quantitative ultrasound (QUS) parameters of velocity and attenuation are dependent upon both bone quantity and bone quality, although it has not been possible to date to transpose one particular QUS parameter into separate estimates of quantity and quality. It has recently been shown that ultrasound transit time spectroscopy (UTTS) may provide an accurate estimate of bone density and hence quantity. We hypothesised that UTTS also has the potential to provide an estimate of bone structure and hence quality. In this in-vitro study, 16 human femoral bone samples were tested utilising three techniques; UTTS, micro computed tomography (μCT), and mechanical testing. UTTS was utilised to estimate bone volume fraction (BV/TV) and two novel structural parameters, inter-quartile range of the derived transit time (UTTS-IQR) and the transit time of maximum proportion of sonic-rays (TTMP). μCT was utilised to derive BV/TV along with several bone structure parameters. A destructive mechanical test was utilised to measure the stiffness and strength (failure load) of the bone samples. BV/TV was calculated from the derived transit time spectrum (TTS); the correlation coefficient (R 2 ) with μCT-BV/TV was 0.885. For predicting mechanical stiffness and strength, BV/TV derived by both μCT and UTTS provided the strongest correlation with mechanical stiffness (R 2 =0.567 and 0.618 respectively) and

Processing of microCT implant-bone systems images using Fuzzy Mathematical Morphology

International Nuclear Information System (INIS)

Bouchet, A; Pastore, J; Colabella, L; Omar, S; Ballarre, J

2016-01-01

The relationship between a metallic implant and the existing bone in a surgical permanent prosthesis is of great importance since the fixation and osseointegration of the system leads to the failure or success of the surgery. Micro Computed Tomography is a technique that helps to visualize the structure of the bone. In this study, the microCT is used to analyze implant-bone systems images. However, one of the problems presented in the reconstruction of these images is the effect of the iron based implants, with a halo or fluorescence scattering distorting the micro CT image and leading to bad 3D reconstructions. In this work we introduce an automatic method for eliminate the effect of AISI 316L iron materials in the implant-bone system based on the application of Compensatory Fuzzy Mathematical Morphology for future investigate about the structural and mechanical properties of bone and cancellous materials. (paper)

68Ga-PSMA PET/CT in the evaluation of bone metastases in prostate cancer.

Science.gov (United States)

Sachpekidis, Christos; Bäumer, P; Kopka, K; Hadaschik, B A; Hohenfellner, M; Kopp-Schneider, A; Haberkorn, U; Dimitrakopoulou-Strauss, A

2018-06-01

The aims of this retrospective analysis were to compare 68 Ga-PSMA PET findings and low-dose CT findings (120 kV, 30 mA), and to obtain semiquantitative and quantitative 68 Ga-PSMA PET data in patients with prostate cancer (PC) bone metastases. In total, 152 PET/CT scans from 140 patients were evaluated. Of these patients, 30 had previously untreated primary PC, and 110 had biochemical relapse after treatment of primary PC. All patients underwent dynamic PET/CT scanning of the pelvis and lower abdomen as well as whole-body PET/CT with 68 Ga-PSMA-11. The PET/CT scans were analysed qualitatively (visually), semiquantitatively (SUV), and quantitatively based on a two-tissue compartment model and a noncompartmental approach leading to the extraction of the fractal dimension. Differences were considered significant for p values PET-positive and CT-positive, 65 were only 68 Ga-PSMA-positive, and 10 were only CT-positive. The Yang test showed that there were significantly more 68 Ga-PSMA PET-positive lesions than CT-positive lesions. Association analysis showed that PSA plasma levels were significantly correlated with several 68 Ga-PSMA-11-associated parameters in bone metastases, including the degree of tracer uptake (SUV average and SUV max ), its transport rate from plasma to the interstitial/intracellular compartment (K 1 ), its rate of binding to the PSMA receptor and its internalization (k 3 ), its influx rate (K i ), and its distribution heterogeneity. 68 Ga-PSMA PET/CT is a useful diagnostic tool in the detection of bone metastases in PC. 68 Ga-PSMA PET visualizes more bone metastases than low-dose CT. PSA plasma levels are significantly correlated with several 68 Ga-PSMA PET parameters.

A Novel Markerless Technique to Evaluate Daily Lung Tumor Motion Based on Conventional Cone-Beam CT Projection Data

International Nuclear Information System (INIS)

Yang Yin; Zhong Zichun; Guo Xiaohu; Wang Jing; Anderson, John; Solberg, Timothy; Mao Weihua

2012-01-01

Purpose: In this study, we present a novel markerless technique, based on cone beam computed tomography (CBCT) raw projection data, to evaluate lung tumor daily motion. Method and Materials: The markerless technique, which uses raw CBCT projection data and locates tumors directly on every projection, consists of three steps. First, the tumor contour on the planning CT is used to create digitally reconstructed radiographs (DRRs) at every projection angle. Two sets of DRRs are created: one showing only the tumor, and another with the complete anatomy without the tumor. Second, a rigid two-dimensional image registration is performed to register the DRR set without the tumor to the CBCT projections. After the registration, the projections are subtracted from the DRRs, resulting in a projection dataset containing primarily tumor. Finally, a second registration is performed between the subtracted projection and tumor-only DRR. The methodology was evaluated using a chest phantom containing a moving tumor, and retrospectively in 4 lung cancer patients treated by stereotactic body radiation therapy. Tumors detected on projection images were compared with those from three-dimensional (3D) and four-dimensional (4D) CBCT reconstruction results. Results: Results in both static and moving phantoms demonstrate that the accuracy is within 1 mm. The subsequent application to 22 sets of CBCT scan raw projection data of 4 lung cancer patients includes about 11,000 projections, with the detected tumor locations consistent with 3D and 4D CBCT reconstruction results. This technique reveals detailed lung tumor motion and provides additional information than conventional 4D images. Conclusion: This technique is capable of accurately characterizing lung tumor motion on a daily basis based on a conventional CBCT scan. It provides daily verification of the tumor motion to ensure that these motions are within prior estimation and covered by the treatment planning volume.

Evaluation of Bone Metastasis from Hepatocellular Carcinoma Using {sup 18F} FDG PET/CT and {sup 99mT}c HDP Bone Scintigraphy: Characteristics of Soft Tissue Formation

Energy Technology Data Exchange (ETDEWEB)

Seo, Hyo Jung; Choi, Yun Jung; Kim, Hyun Jeong; Jeong, Youg Hyu; Cho, Arthur; Lee, Jae Hoon; Yun, Mijin; Choi, Hye Jin; Lee, Jong Doo; Kang, Won Jun [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

2011-09-15

Bone metastasis from hepatocellular carcinoma (HCC) can present with soft tissue formation, resulting in oncologic emergency. Contrast enhanced FDG PET/CT and bone scintigraphy were compared to evaluate characteristics of bone metastases with of without soft tissue formation from HCC. of 4,151 patients with HCC, 263 patients had bone metastases. Eighty five patients with bone metastasis from HCC underwent contrast enhanced FDG PET/CT. Fifty four of the enrolled subjects had recent {sup 99mT}c HDP bone scintigraphy available for comparison. Metastatic bone lesions were identified with visual inspection on FDG PET/CT, and maximum standardized uptake value (SUVmax) was used for the quantitative analysis. Confirmation of bone metastasis was based on histopathology, combined imaging modalities, or serial follow up studies. Forty seven patients (55%) presented with soft tissue formation, while the remaining 38 patients presented without soft tissue formation. Frequent sites of bone metastases from HCC were the spine (39%), pelvis (19%), and rib cage (14%). The soft tissue formation group had more frequent bone pain (77 vs. 37%, p<0.0001), higher SUVmax (6.02 vs. 3.52, p<0.007), and higher incidence of photon defect in bone scintigraphy (75 vs. 0%) compared to the non soft tissue formation group. FDG PET/CT had higher detection rate for bone metastasis than bone scintigraphy both in lesion based analysis (98 vs. 53%, p=0.0015) and in patient based analysis (100 vs. 80%, p<0.001). Bone metastasis from HCC showed a high incidence of soft tissue formation requiring emergency treatment. Although the characteristic findings for soft tissue formation such as photon defect in bone scintigraphy are helpful in detection, overall detectability of bone metastasis is higher in FDG PET/CT. Contrast enhanced PET/CT will be useful in finding and delineating soft tissue forming bone metastasis from HCC.

Diagnostic role of (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging for early and atypical bone metastases.

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Chen, Xiao-Liang; Li, Qian; Cao, Lin; Jiang, Shi-Xi

2014-01-01

The bone metastasis appeared early before the bone imaging for most of the above patients. (99)Tc(m)-MDP ((99)Tc(m) marked methylene diphosphonate) bone imaging could diagnosis the bone metastasis with highly sensitivity, but with lower specificity. The aim of this study is to explore the diagnostic value of (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging for the early period atypical bone metastases. 15 to 30 mCi (99)Tc(m)-MDP was intravenously injected to the 34 malignant patients diagnosed as doubtful early bone metastases. SPECT, CT and SPECT/CT images were captured and analyzed consequently. For the patients diagnosed as early period atypical bone metastases by SPECT/CT, combining the SPECT/CT and MRI together as the SPECT/MRI integrated image. The obtained SPECT/MRI image was analyzed and compared with the pathogenic results of patients. The results indicated that 34 early period doubtful metastatic focus, including 34 SPECT positive focus, 17 focus without special changes by using CT method, 11 bone metastases focus by using SPECT/CT method, 23 doubtful bone metastases focus, 8 doubtful bone metastases focus, 14 doubtful bone metastases focus and 2 focus without clear image. Totally, SPECT/CT combined with SPECT/MRI method diagnosed 30 bone metastatic focus and 4 doubtfully metastatic focus. In conclusion, (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging shows a higher diagnostic value for the early period bone metastases, which also enhances the diagnostic accuracy rate.

11C-choline vs. 18F-FDG PET/CT in assessing bone involvement in patients with multiple myeloma

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Ambrosini Valentina

2007-06-01

Full Text Available Abstract Background Multiple Myeloma (MM is a B cell neoplasm causing lytic or osteopenic bone abnormalities. Whole body skeletal survey (WBSS, Magnetic resonance (MR and 18F-FDG PET/CT are imaging techniques routinely used for the evaluation of bone involvement in MM patients. Aim As MM bone lesions may present low 18F-FDG uptake; the aim of this study was to assess the possible added value and limitations of 11C-Choline to that of 18F-FDG PET/CT in patients affected with MM. Methods Ten patients affected with MM underwent a standard 11C-Choline PET/CT and an 18F-FDG PET/CT within one week. The results of the two scans were compared in terms of number, sites and SUVmax of lesions. Results Four patients (40% had a negative concordant 11C-Choline and 18F-FDG PET/CT scans. Two patients (20% had a positive 11C-Choline and 18F-FDG PET/CT scans that identified the same number and sites of bone lesions. The remaining four patients (40% had a positive 11C-Choline and 18F-FDG PET/CT scan, but the two exams identified different number of lesions. Choline showed a mean SUVmax of 5 while FDG showed a mean SUVmax of 3.8 (P = 0.042. Overall, 11C-Choline PET/CT scans detected 37 bone lesions and 18F-FDG PET/CT scans detected 22 bone lesions but the difference was not significant (P = 0.8. Conclusion According to these preliminary data, 11C-Choline PET/CT appears to be more sensitive than 18F-FDG PET/CT for the detection of bony myelomatous lesions. If these data are confirmed in larger series of patients, 11C-Choline may be considered a more appropriate functional imaging in association with MRI for MM bone staging.

Evaluation of bone formation in calcium phosphate scaffolds with μCT-method validation using SEM.

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Lewin, S; Barba, A; Persson, C; Franch, J; Ginebra, M-P; Öhman-Mägi, C

2017-10-05

There is a plethora of calcium phosphate (CaP) scaffolds used as synthetic substitutes to bone grafts. The scaffold performance is often evaluated from the quantity of bone formed within or in direct contact with the scaffold. Micro-computed tomography (μCT) allows three-dimensional evaluation of bone formation inside scaffolds. However, the almost identical x-ray attenuation of CaP and bone obtrude the separation of these phases in μCT images. Commonly, segmentation of bone in μCT images is based on gray scale intensity, with manually determined global thresholds. However, image analysis methods, and methods for manual thresholding in particular, lack standardization and may consequently suffer from subjectivity. The aim of the present study was to provide a methodological framework for addressing these issues. Bone formation in two types of CaP scaffold architectures (foamed and robocast), obtained from a larger animal study (a 12 week canine animal model) was evaluated by μCT. In addition, cross-sectional scanning electron microscopy (SEM) images were acquired as references to determine thresholds and to validate the result. μCT datasets were registered to the corresponding SEM reference. Global thresholds were then determined by quantitatively correlating the different area fractions in the μCT image, towards the area fractions in the corresponding SEM image. For comparison, area fractions were also quantified using global thresholds determined manually by two different approaches. In the validation the manually determined thresholds resulted in large average errors in area fraction (up to 17%), whereas for the evaluation using SEM references, the errors were estimated to be less than 3%. Furthermore, it was found that basing the thresholds on one single SEM reference gave lower errors than determining them manually. This study provides an objective, robust and less error prone method to determine global thresholds for the evaluation of bone formation in

CT diagnosis and differential diagnosis of otodystrophic lesions of the temporal bone

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D' Archambeau, O.; Parizel, P.M.; Schepper, A.M. De (Antwerp University Hospital (Belgium). Department of Radiology); Koekelkoren, E.; Van De Heyning, P. (Antwerp University Hospital (Belgium). Department of E.N.T.)

The purpose of this study was to assess the diagnostic and differential diagnostic value of high-resolution computed tomography in the evaluation of temporal-bone dystrophies. The study group included 55 patients with osseous abnormalities of the temporal bone in general, and the labyrinthine capsule in particular. In 27 patients the CT scan revealed evidence of otodystrophic lesions. The CT findings in patients with otosclerosis (21 patients), osteogenesis imperfecta (two patients), fibrous dysplasia (one patient). Paget's disease (one patient) and osteoporosis (two patients) are described. The CT scans of 17 patients revealed secondary osseous lesions due to metastasis (five patients), post-inflammatory changes (10 patients) or labyrinthitis ossificans (two patients). Normal variants and congenital mineralization defects were diagnosed in nine patients, Down's syndrome in two. Our results indicate the importance of high-resolution computed tomography as the primary imaging modality in evaluating osseous lesions of the temporal bone and labyrinth. (author). 14 refs.; 13 figs; 2 tabs.

CT diagnosis and differential diagnosis of otodystrophic lesions of the temporal bone

International Nuclear Information System (INIS)

D'Archambeau, O.; Parizel, P.M.; Schepper, A.M. De; Koekelkoren, E.; Van De Heyning, P.

1990-01-01

The purpose of this study was to assess the diagnostic and differential diagnostic value of high-resolution computed tomography in the evaluation of temporal-bone dystrophies. The study group included 55 patients with osseous abnormalities of the temporal bone in general, and the labyrinthine capsule in particular. In 27 patients the CT scan revealed evidence of otodystrophic lesions. The CT findings in patients with otosclerosis (21 patients), osteogenesis imperfecta (two patients), fibrous dysplasia (one patient). Paget's disease (one patient) and osteoporosis (two patients) are described. The CT scans of 17 patients revealed secondary osseous lesions due to metastasis (five patients), post-inflammatory changes (10 patients) or labyrinthitis ossificans (two patients). Normal variants and congenital mineralization defects were diagnosed in nine patients, Down's syndrome in two. Our results indicate the importance of high-resolution computed tomography as the primary imaging modality in evaluating osseous lesions of the temporal bone and labyrinth. (author). 14 refs.; 13 figs; 2 tabs

Comparison of bone-implant contact and bone-implant volume between 2D-histological sections and 3D-SRµCT slices

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R Bernhardt

2012-04-01

Full Text Available Histological imaging is still considered the gold standard for analysing bone formation around metallic implants. Generally, a limited number of histological sections per sample are used for the approximation of mean values of peri-implant bone formation. In this study we compared statistically the results of bone-implant contact (BIC and bone-implant volume (BIV obtained by histological sections, with those obtained by X-ray absorption images from synchrotron radiation micro-computed tomography (SRµCT using osseointegrated screw-shaped implants from a mini-pig study. Comparing the BIC results of 3-4 histological sections per implant sample with the appropriate 3-4 SRµCT slices showed a non-significant difference of 1.9 % (p = 0.703. The contact area assessed by the whole 3D information from the SRµCT measurement in comparison to the histomorphometric results showed a non-significant difference in BIC of 4.9 % (p = 0.171. The amount of the bone-implant volume in the histological sections and the appropriate SRµCT slices showed a non-significant difference by only 1.4 % (p = 0.736 and also remains non-significant with 2.6 % (p = 0.323 using the volumetric SRµCT information. We conclude that for a clinical evaluation of implant osseointegration with histological imaging at least 3-4 sections per sample are sufficient to represent the BIC or BIV for a sample. Due to the fact that in this study we have found a significant intra-sample variation in BIC of up to ± 35 % the selection of only one or two histological sections per sample may strongly influence the determined BIC.

Evaluating differential nuclear DNA yield rates and osteocyte numbers among human bone tissue types: A synchrotron radiation micro-CT approach.

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Andronowski, Janna M; Mundorff, Amy Z; Pratt, Isaac V; Davoren, Jon M; Cooper, David M L

2017-05-01

Molecular human identification has conventionally focused on DNA sampling from dense, weight-bearing cortical bone tissue, typically from femora or tibiae. A comparison of skeletal elements from three contemporary individuals demonstrated that elements with high quantities of cancellous bone yielded nuclear DNA at the highest rates, suggesting that preferentially sampling cortical bone may be suboptimal (Mundorff & Davoren, 2014). Despite these findings, the reason for the differential DNA yields between cortical and cancellous bone tissues remains unknown. The primary goal of this work is to ascertain whether differences in bone microstructure can be used to explain differential nuclear DNA yield among bone tissue types observed by Mundorff and Davoren (2014), with a focus on osteocytes and the three-dimensional (3D) quantification of their associated lacunae. Osteocytes and other bone cells are recognized to house DNA in bone tissue, thus examining the density of their lacunae may explain why nuclear DNA yield rates differ among bone tissue types. Lacunae were visualized and quantified using synchrotron radiation-based micro-Computed Tomographic imaging (SR micro-CT). Volumes of interest (VOIs) from cortical and cancellous bone tissues (n=129) were comparatively analyzed from the three skeletons sampled for Mundorff and Davoren's (2014) study. Analyses tested the primary hypothesis that the abundance and density of osteocytes (inferred from their lacunar spaces) vary between cortical and cancellous bone tissue types. Results demonstrated that osteocyte lacunar abundance and density vary between cortical and cancellous bone tissue types, with cortical bone VOIs containing a higher lacunar abundance and density. We found that the osteocyte lacunar density values are independent of nuclear DNA yield, suggesting an alternative explanation for the higher nuclear DNA yields from bones with greater quantities of cancellous bone tissue. The use of SR micro-CT allowed for

Digital contrast subtraction radiography for proximal caries diagnosis

International Nuclear Information System (INIS)

Kang, Byung Cheol; Yoon, Suk Ja

2002-01-01

To determine whether subtraction images utilizing contrast media can improve the diagnostic performance of proximal caries diagnosis compared to conventional periapical radiographic images. Thirty-six teeth with 57 proximal surfaces were radiographied using a size no.2 RVG-ui sensor (Trophy Radiology, Marne-la-Vallee, France). The teeth immersed in water-soluble contrast media and subtraction images were taken. Each tooth was then sectioned for histologic examination. The digital radiographic images and subtraction images were examined and interpreted by three dentists for proximal caries. The results of the proximal caries diagnosis were then verified with the results of the histologic examination. The proximal caries sensitivity using digital subtraction radiography was significantly higher than simply examining a single digital radiograph. The sensitivity of the proximal dentinal carious lesion when analyzed with the subtraction radiograph and the radiograph together was higher than with the subtraction radiograph or the radiograph alone. The use of subtraction radiography with contrast media may be useful for detecting proximal dentinal carious lesions.

Differential diagnosis between chronic otitis media with and without cholesteatoma by temporal bone CT: focus on bone change and mass effect

International Nuclear Information System (INIS)

Jung, Cheol Kyu; Park, Dong Woo; Seong, Jin Yong; Lee, Kak Soo; Park Choong Ki; Lee, Seung Ro; Hahm, Chang Kok

2000-01-01

In order to determine specific differences, we compared the temporal bone CT findings of chronic otitis media (COM) with and without cholesteatoma, focusing on bone change. Between 1997 and 1998, 82 patients (84 cases) underwent temporal bone CT and were shown to have COM, with or without cholesteatoma after mastoidectomy and tympanoplasty. There were 36 cases of COM with cholesteatoma (26 patients, M:F =3D 11:15; age range, 16-61 (mean, 36,2) years), and 58 cases without chlesteatoma (56 patients, M:F =3D 25:31, age range, 15-61 (mean, 36.2) years). The findings of temporal bone CT were analysed at the point of bony changes including erosion and medial displacement of ossicles (malleus, incus, and stapes), erosion or destruction of the scutum, tegmen, facial canal, and lateral semicircular canal, and ballooning of the tympanic cavity and mastoid antrum. In addition, the soft tissue changes seen on temporal bone CT were analyzed at the site of lateral bulging of soft tissue in Prussak's space, perforation of the pars flaccida, tympanic membrane retraction, and tympanosclerosis. We retrospectively compared the findings of temporal bone CT with the surgical findings, and to assess statistical significance, the Chi-square test was used. Bone erosion or destruction was seen in 36.2% of COM cases without cholesteatoma, and in 96.2% of cases with cholesteatoma. Comparing COM with and without cholesteatoma, the erosion of ossicles including the malleus (81%, 24%), incus (88%, 14%), stapes (58%, 10%), scutum (88%, 10%), facial canal (8%, 0%), and lateral semicircular canal (8%, 0%), was more common in COM with cholesteatoma (p-value less than 0.05), with the exception of erosion of the tegmen (8%, 3%). Other bony changes including medial displacement of ossicles (27%, 3%), ballooning of tympanic cavity and mastoid antrum (96%, 16%), and the soft tissue changes including lateral bulging of soft tissue in Prussak's space (58%, 14%) and perforation of the pars flaccida (35

Differential diagnosis between chronic otitis media with and without cholesteatoma by temporal bone CT: focus on bone change and mass effect

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Jung, Cheol Kyu; Park, Dong Woo; Seong, Jin Yong; Lee, Kak Soo; Park Choong Ki; Lee, Seung Ro; Hahm, Chang Kok [College of Medicine, Hanyang University, Seoul (Korea, Republic of)

2000-01-01

In order to determine specific differences, we compared the temporal bone CT findings of chronic otitis media (COM) with and without cholesteatoma, focusing on bone change. Between 1997 and 1998, 82 patients (84 cases) underwent temporal bone CT and were shown to have COM, with or without cholesteatoma after mastoidectomy and tympanoplasty. There were 36 cases of COM with cholesteatoma (26 patients, M:F =3D 11:15; age range, 16-61 (mean, 36,2) years), and 58 cases without chlesteatoma (56 patients, M:F =3D 25:31, age range, 15-61 (mean, 36.2) years). The findings of temporal bone CT were analysed at the point of bony changes including erosion and medial displacement of ossicles (malleus, incus, and stapes), erosion or destruction of the scutum, tegmen, facial canal, and lateral semicircular canal, and ballooning of the tympanic cavity and mastoid antrum. In addition, the soft tissue changes seen on temporal bone CT were analyzed at the site of lateral bulging of soft tissue in Prussak's space, perforation of the pars flaccida, tympanic membrane retraction, and tympanosclerosis. We retrospectively compared the findings of temporal bone CT with the surgical findings, and to assess statistical significance, the Chi-square test was used. Bone erosion or destruction was seen in 36.2% of COM cases without cholesteatoma, and in 96.2% of cases with cholesteatoma. Comparing COM with and without cholesteatoma, the erosion of ossicles including the malleus (81%, 24%), incus (88%, 14%), stapes (58%, 10%), scutum (88%, 10%), facial canal (8%, 0%), and lateral semicircular canal (8%, 0%), was more common in COM with cholesteatoma (p-value less than 0.05), with the exception of erosion of the tegmen (8%, 3%). Other bony changes including medial displacement of ossicles (27%, 3%), ballooning of tympanic cavity and mastoid antrum (96%, 16%), and the soft tissue changes including lateral bulging of soft tissue in Prussak's space (58%, 14%) and perforation of the pars

Three-dimensional visualization and characterization of bone structure using reconstructed in-vitro μCT images: A pilot study for bone microarchitecture analysis

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Latief, Fourier Dzar Eljabbar, E-mail: fourier@fi.itb.ac.id [Physics of Earth and Complex Systems, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia); Dewi, Dyah Ekashanti Octorina [2Biomedical Engineering Research Division, School of Electrical Engineering and Informatics, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia); Shari, Mohd Aliff Bin Mohd [Faculty of Electrical Engineering, Universiti Teknologi MARA Malaysia, 40000 Shah Alam, Selangor (Malaysia)

2014-03-24

Micro Computed Tomography (μCT) has been largely used to perform micrometer scale imaging of specimens, bone biopsies and small animals for the study of porous or cavity-containing objects. One of its favored applications is for assessing structural properties of bone. In this research, we perform a pilot study to visualize and characterize bone structure of a chicken bone thigh, as well as to delineate its cortical and trabecular bone regions. We utilize an In-Vitro μCT scanner Skyscan 1173 to acquire a three dimensional image data of a chicken bone thigh. The thigh was scanned using X-ray voltage of 45 kV and current of 150 μA. The reconstructed images have spatial resolution of 142.50 μm/pixel. Using image processing and analysis e.i segmentation by thresholding the gray values (which represent the pseudo density) and binarizing the images, we were able to visualize each part of the bone, i.e., the cortical and trabecular regions. Total volume of the bone is 4663.63 mm{sup 3}, and the surface area of the bone is 7913.42 mm{sup 2}. The volume of the cortical is approximately 1988.62 mm{sup 3} which is nearly 42.64% of the total bone volume. This pilot study has confirmed that the μCT is capable of quantifying 3D bone structural properties and defining its regions separately. For further development, these results can be improved for understanding the pathophysiology of bone abnormality, testing the efficacy of pharmaceutical intervention, or estimating bone biomechanical properties.

Advanced Background Subtraction Applied to Aeroacoustic Wind Tunnel Testing

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Bahr, Christopher J.; Horne, William C.

2015-01-01

An advanced form of background subtraction is presented and applied to aeroacoustic wind tunnel data. A variant of this method has seen use in other fields such as climatology and medical imaging. The technique, based on an eigenvalue decomposition of the background noise cross-spectral matrix, is robust against situations where isolated background auto-spectral levels are measured to be higher than levels of combined source and background signals. It also provides an alternate estimate of the cross-spectrum, which previously might have poor definition for low signal-to-noise ratio measurements. Simulated results indicate similar performance to conventional background subtraction when the subtracted spectra are weaker than the true contaminating background levels. Superior performance is observed when the subtracted spectra are stronger than the true contaminating background levels. Experimental results show limited success in recovering signal behavior for data where conventional background subtraction fails. They also demonstrate the new subtraction technique's ability to maintain a proper coherence relationship in the modified cross-spectral matrix. Beam-forming and de-convolution results indicate the method can successfully separate sources. Results also show a reduced need for the use of diagonal removal in phased array processing, at least for the limited data sets considered.

MRI and PET/CT of patients with bone metastases from breast carcinoma

International Nuclear Information System (INIS)

Grankvist, J.; Fisker, R.; Iyer, V.; Fründ, E.T.; Simonsen, C.; Christensen, T.; Stenbygaard, L.; Ewertz, M.; Larsson, E.-M.

2012-01-01

3.0 Tesla magnetic resonance imaging (MRI) with diffusion-weighted imaging (DWI) was compared with combined 18F-fluorodeoxyglucose positron emission tomography and computed tomography (PET/CT) in patients with suspected bone metastases from breast cancer. A prospective clinical study was performed in 13 female breast cancer patients (mean age 61years; range 45–85 years). The spine was imaged in the sagittal plane with T1-weighted (T1), short tau inversion recovery (STIR), and T2-weighted fat-saturated (T2) sequences. The pelvis was imaged similarly in the coronal plane. Axial DWI was performed from the skull base to the mid-thigh. MRI and PET/CT were performed in all patients at a maximum interval of 10 working days and at least 14 days after chemotherapy. MRI was reviewed by two radiologists, and their consensus on potential metastases in 27 predefined locations was recorded. The predefined locations were the vertebral bodies (24), the left (1) and right (1) pelvic bones, and the sacral bone (1). The PET/CT was reviewed by a radiologists and a nuclear medicine physician. MRI detected 59 of the 60 active metastases found with our gold standard modality PET/CT. T1 had the highest sensitivity (98%) but rather low specificity (77%), but with the addition of STIR and DWI, the specificity increased to 95%. The additional metastases detected with MRI most likely represented postherapeutic residual scars without active tumour. In conclusion, 3.0 Tesla MRI with T1, STIR, and DWI is useful for the clinical evaluation of bone metastases from breast cancer and compares well to PET/CT.

Conventional multi-slice computed tomography (CT) and cone-beam CT (CBCT) for computer-assisted implant placement. Part I: relationship of radiographic gray density and implant stability.

Science.gov (United States)

Arisan, Volkan; Karabuda, Zihni Cüneyt; Avsever, Hakan; Özdemir, Tayfun

2013-12-01

The relationship of conventional multi-slice computed tomography (CT)- and cone beam CT (CBCT)-based gray density values and the primary stability parameters of implants that were placed by stereolithographic surgical guides were analyzed in this study. Eighteen edentulous jaws were randomly scanned by a CT (CT group) or a CBCT scanner (CBCT group) and radiographic gray density was measured from the planned implants. A total of 108 implants were placed, and primary stability parameters were measured by insertion torque value (ITV) and resonance frequency analysis (RFA). Radiographic and subjective bone quality classification (BQC) was also classified. Results were analyzed by correlation tests and multiple regressions (p < .05). CBCT-based gray density values (765 ± 97.32 voxel value) outside the implants were significantly higher than those of CT-based values (668.4 ± 110 Hounsfield unit, p < .001). Significant relations were found among the gray density values outside the implants, ITV (adjusted r(2)  = 0.6142, p = .001 and adjusted r(2)  = 0.5166, p = .0021), and RFA (adjusted r(2)  = 0.5642, p = .0017 and adjusted r(2)  = 0.5423, p = .0031 for CT and CBCT groups, respectively). Data from radiographic and subjective BQC were also in agreement. Similar to the gray density values of CT, that of CBCT could also be predictive for the subjective BQC and primary implant stability. Results should be confirmed on different CBCT scanners. © 2012 Wiley Periodicals, Inc.

Automated assessment of bone changes in cross-sectional micro-CT studies of murine experimental osteoarthritis.

Science.gov (United States)

Das Neves Borges, Patricia; Vincent, Tonia L; Marenzana, Massimo

2017-01-01

The degradation of articular cartilage, which characterises osteoarthritis (OA), is usually paired with excessive bone remodelling, including subchondral bone sclerosis, cysts, and osteophyte formation. Experimental models of OA are widely used to investigate pathogenesis, yet few validated methodologies for assessing periarticular bone morphology exist and quantitative measurements are limited by manual segmentation of micro-CT scans. The aim of this work was to chart the temporal changes in periarticular bone in murine OA by novel, automated micro-CT methods. OA was induced by destabilisation of the medial meniscus (DMM) in 10-week old male mice and disease assessed cross-sectionally from 1- to 20-weeks post-surgery. A novel approach was developed to automatically segment subchondral bone compartments into plate and trabecular bone in micro-CT scans of tibial epiphyses. Osteophyte volume, as assessed by shape differences using 3D image registration, and by measuring total epiphyseal volume was performed. Significant linear and volumetric structural modifications in subchondral bone compartments and osteophytes were measured from 4-weeks post-surgery and showed progressive changes at all time points; by 20 weeks, medial subchondral bone plate thickness increased by 160±19.5 μm and the medial osteophyte grew by 0.124±0.028 μm3. Excellent agreement was found when automated measurements were compared with manual assessments. Our automated methods for assessing bone changes in murine periarticular bone are rapid, quantitative, and highly accurate, and promise to be a useful tool in future preclinical studies of OA progression and treatment. The current approaches were developed specifically for cross-sectional micro-CT studies but could be applied to longitudinal studies.

Automated assessment of bone changes in cross-sectional micro-CT studies of murine experimental osteoarthritis.

Directory of Open Access Journals (Sweden)

Patricia Das Neves Borges

Full Text Available The degradation of articular cartilage, which characterises osteoarthritis (OA, is usually paired with excessive bone remodelling, including subchondral bone sclerosis, cysts, and osteophyte formation. Experimental models of OA are widely used to investigate pathogenesis, yet few validated methodologies for assessing periarticular bone morphology exist and quantitative measurements are limited by manual segmentation of micro-CT scans. The aim of this work was to chart the temporal changes in periarticular bone in murine OA by novel, automated micro-CT methods.OA was induced by destabilisation of the medial meniscus (DMM in 10-week old male mice and disease assessed cross-sectionally from 1- to 20-weeks post-surgery. A novel approach was developed to automatically segment subchondral bone compartments into plate and trabecular bone in micro-CT scans of tibial epiphyses. Osteophyte volume, as assessed by shape differences using 3D image registration, and by measuring total epiphyseal volume was performed.Significant linear and volumetric structural modifications in subchondral bone compartments and osteophytes were measured from 4-weeks post-surgery and showed progressive changes at all time points; by 20 weeks, medial subchondral bone plate thickness increased by 160±19.5 μm and the medial osteophyte grew by 0.124±0.028 μm3. Excellent agreement was found when automated measurements were compared with manual assessments.Our automated methods for assessing bone changes in murine periarticular bone are rapid, quantitative, and highly accurate, and promise to be a useful tool in future preclinical studies of OA progression and treatment. The current approaches were developed specifically for cross-sectional micro-CT studies but could be applied to longitudinal studies.

A digital subtraction radiography based tool for periodontal bone resorption analysis

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Schiabel, Homero; Rodrigues, Eveline B., E-mail: homero@sc.usp.br [University of Sao Paulo (EESC/USP), Sao Carlos, SP (Brazil). Dept. of Electrical Engineering; Rubira-Bullen, Izabel R.F. [University of Sao Paulo (USP), Bauru, SP (Brazil). Bauru Dentistry School

2011-07-01

The aim of this paper was to describe an aided diagnosis scheme for periodontal bone resorption so that the dentist can make an early diagnosis of the periodontal disease and establish the best treatment plan to increase the success of healing. Three ways of displaying the results are provided: qualitative, simple quantitative and colored-percentage quantitative views. A total of 72 pairs of in vitro radiographic images were used. The main procedure registers the images perspective projection aimed to align them in rotation and translation, and is followed by the application of a contrast correction technique. The results from the subtraction were evaluated firstly by the comparison between the actual and the digital sizes corresponding to the holes made by drills in phantoms. The mean error was 4.2%. The method was also applied to actual tooth radiographic images and could detect clearly the effect of treatment of periodontal diseases. It is dependent on the reproducibility of the process of radiographs acquisition and digitization, but the calculated mean error allows to conclude its better efficacy compared to usual procedures in this field. (author)

A digital subtraction radiography based tool for periodontal bone resorption analysis

International Nuclear Information System (INIS)

Schiabel, Homero; Rodrigues, Eveline B.; Rubira-Bullen, Izabel R.F.

2011-01-01

The aim of this paper was to describe an aided diagnosis scheme for periodontal bone resorption so that the dentist can make an early diagnosis of the periodontal disease and establish the best treatment plan to increase the success of healing. Three ways of displaying the results are provided: qualitative, simple quantitative and colored-percentage quantitative views. A total of 72 pairs of in vitro radiographic images were used. The main procedure registers the images perspective projection aimed to align them in rotation and translation, and is followed by the application of a contrast correction technique. The results from the subtraction were evaluated firstly by the comparison between the actual and the digital sizes corresponding to the holes made by drills in phantoms. The mean error was 4.2%. The method was also applied to actual tooth radiographic images and could detect clearly the effect of treatment of periodontal diseases. It is dependent on the reproducibility of the process of radiographs acquisition and digitization, but the calculated mean error allows to conclude its better efficacy compared to usual procedures in this field. (author)

Combined use of intraarterial digital subtraction angiography with conventional retrograde brachial vertebral angiography

International Nuclear Information System (INIS)

Yamaguchi, Tatsuo; Ogawa, Toshihide; Inugami, Atsushi; Kawata, Yasushi; Shishido, Fumio; Uemura, Kazuo

1985-01-01

For 102 patients who had the examination of conventional bilaterally retrograde brachial vertebral angiography (retrograde VAG), intraarterial digital subtraction angiography (DSA) was successively performed to investigate steno-occlusive lesions of proximal vertebral and subclavian arteries. All the patients had no complication due to the DSA procedure. In 50% of 72 ischemic stroke cases, positive findings were found either in the origin of the vertebral artery or in the subclavian artery. Stenosis of more than 50% of the lumen of the vertebral artery were found in 14% of the cases at the origin of the right one and also in 14% in the left one. Occlusion of the vertebral artery was found in 4% in the left side only. In 30 cases with non-ischemic brain diseases, positive findings were noted in 10%. Intraarterial DSA combined with retrograde VAG was thought to be useful, especially in the examination for ischemic stroke. (author)

Three dimensional CT of stapes. Stapedial imagings in dry temporal bone and clinical applications

Energy Technology Data Exchange (ETDEWEB)

Edamatsu, Hideo; Kubota, Osamu; Yamashita, Koichi [Kanazawa Medical Univ., Ishikawa (Japan)

1995-03-01

This study was performed to evaluate the usefulness and limitations of three dimensional (3-D) imagings of stapes in the middle ear by high speed helical CT. One dissected human temporal bone, ten normal and diseased ears were scanned with a slice of 1.0 mm and reconstructed in a thickness of 0.2-0.5 mm. Every specimen of 3-D can be observed in any plane and from any direction. Ossicular imagings of the temporal bone in 3-D were reconstructed as if the malleus, incus and stapes were observed under microscope. The whole structure of stapes was impossible to be represented by two dimensional CT heretofore in use, but 3-D in our study showed the head, crus and foot plate of the stapes in detail. Stapedial imagings of 3-D CT in normal ears showed the same findings as those recorded in temporal bone. Preoperative diagnostic findings of ossicles in the affected ears were very useful. Especially in ossicular anomalies, 3-D CT was positive in diagnosis and its accuracies were confirmed with operative observation. For the postoperative evaluation concerning the ossicular reconstruction, i.e. TORP and PORP, 3-D CT was also important method. It could present an anatomical relation between those prosthesis and the oval window. High speed helical CT can scan an object more quickly and clearly than formerly used CT, and its biological damage for human is less than that of the others. 3-D CT can be more clearly reconstructed with helical CT than former CT. (author).

A Look from the Inside: MicroCT Analysis of Burned Bones

Directory of Open Access Journals (Sweden)

Francesco Boschin

2015-12-01

Full Text Available MicroCT imaging is increasingly used in paleoanthropological and zooarchaeological research to analyse the internal microstructure of bone, replacing comparatively invasive and destructive methods. Consequently the analytical potential of this relatively new 3D imaging technology can be enhanced by developing discipline specific protocols for archaeological analysis. Here we examine how the microstructure of mammal bone changes after burning and explore if X-ray computed microtomography (microCT can be used to obtain reliable information from burned specimens. We subjected domestic pig, roe deer, and red fox bones to burning at different temperatures and for different periods using an oven and an open fire. We observed significant changes in the three-dimensional microstructure of trabecular bone, suggesting that biomechanical studies or other analyses (for instance, determination of age-at-death can be compromised by burning. In addition, bone subjected to very high temperatures (600°C or more became cracked, posing challenges for quantifying characteristics of bone microstructure. Specimens burned at 600°C or greater temperatures, exhibit a characteristic criss-cross cracking pattern concentrated in the cortical region of the epiphyses. This feature, which can be readily observed on the surface of whole bone, could help the identification of heavily burned specimens that are small fragments, where color and surface texture are altered by diagenesis or weathering.

Utility of F-18 FDG PET/CT on the evaluation of primary bone lymphoma.

Science.gov (United States)

Wang, Li-Juan; Wu, Hu-Bing; Wang, Meng; Han, Yan-Jiang; Li, Hong-Sheng; Zhou, Wen-Lan; Wang, Quan-Shi

2015-11-01

Primary bone lymphoma (PBL) is a rare type of malignant lymphoma. Few data have been reported regarding the utility of F-18 FDG PET/CT in this disease. The aim of this study was to assess the role of F-18 FDG PET/CT in the diagnosis and therapeutic effect evaluation of PBL. A total of 19 consecutive patients with PBL were enrolled. Whole-body PET/CT scan was performed for all patients. The diagnosis of PBL was established by histopathology and immunohistochemistry. F-18 FDG PET/CT was positive in 94.7% (18/19) of patients. Uptake of FDG in lesions was intense with SUVmax of 15.14 ± 11.82. Multiple involved lesions were found in 47.4% (9/19) patients, while 52.6% presented with a single involved lesion. Based on the lesions, PET detected 98.9% (87/88) lesions. Among them, 71.6% (63/88) lesions were found to be located in axial skeleton and 28.4% (25/88) in the extremity skeleton. FDG PET/CT also found the lesions infiltrate to the surrounding soft tissue in 84.2% (16/19) patients. On the syn-modality CT, the bone destruction was noted in 43.2% (38/88) of the lesions, of which 50.0% lesions presented as slight change in bone density and 50.0% as severe change. The diagnostic sensitivity of PET was much higher than that of CT (98.9% vs. 43.2%, P=0.000). PET/CT was performed for evaluation of treatment response in 13 patients. In 12 patients with complete response(CR), PET/CT found the 25 lesions were F-18 FDG fully resoluted after treatment, however, bone destruction was still presented in 72.0% (18/25) lesions. The present study suggests that F-18 FDG PET/CT was a sensitive imaging modality for diagnosis and treatment response evaluation of PBL. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Evaluation on temporal bone CT findings of cholesteatoma

International Nuclear Information System (INIS)

Lee, Kun Won; Lee, Nam Joon; Kang, Eun Young; Chung, Kyoo Byung; Suh, Won Hyuck

1989-01-01

Cholesteatomas are thought to result from ingrowth of keratinizing squamous epithelium from external ear to middle ear. The cholesteatomas are usually diagnosed by clinical symptoms and signs, otoscopy, and plain radiograms. But various view points are emphasized radiologically before operation, leading to examine by computed tomography (CT), especially in complicated cases. We retrospectively reviewed the CT findings of cholesteatomas in 25 surgically proven cases during the period from May, 1983 to Aug, 1988. The results were as follows: 1. Most cholesteatomas showed soft tissue mass and bony erosion of ossicles (88%), attic wall and mastoid antrum (84%) on temporal bone CT scan. 2. The CT members of cholesteatomas ranged from 25 to 50 HU (avg. 33 HU). 3. Involved sites were attic (16%), antrum (28%), and both attic and antrum (56%). Other sites were middle ear cavity and external auditory canal. 4. Extra-tympanomastoid extension of cholesteatoma was intracranial abscess (8%), exposure of dural sinus (8%), and extension along with neck (4%)

MicroCT evaluation of bone mineral density loss in human bones

International Nuclear Information System (INIS)

Nogueira, Liebert P.; Braz, Delson; Lopes, Ricardo T.; Barroso, Regina C.; Oliveira, Luis F.

2007-01-01

Bone is a connective tissue largely composed of an organic protein, collagen and the inorganic mineral hydroxyapatite [Ca 10 (PO 4 ) 6 OH 2 ], which combine to provide a mechanical and supportive role in the body. Depending on the orientation of collagen fibers, two types of bone can be distinguished: trabecular and cortical bone. Degree of mineralization is considered an important feature of bone quality. Changes in the degree of mineralization is generally due to osteoporosis, but many recent studies have already shown that alterations in degree of mineralization can occur due to a large variety of factors. The transmission X-ray microtomography is one of the most popular methods, which provides the spatial distribution of the total absorption coefficient inside the sample. The aim of this study was to investigate the suitability of using microCT as a supplementary tool for the diagnosis of the health status of human bones. Eleven samples were constructed simulating the physiological range of bone mineral density (BMD) found in cortical human bone. The samples represent healthy mixtures of swine compact bone dried at room temperature, powdered and mixed with fat (0 - 100 % by mass). The samples were imaged by a microfocus tube (Fein-Focus) with focal size of about 60 μm (±5%), and a CCD camera (0.143 mm pixel size) coupled with an intensifier tube with fluoroscope screen at the Nuclear Instrumentation Laboratory (COPPE/UFRJ), Brazil. The images were reconstructed and treated with suitable software developed at the Nuclear Instrumentation Laboratory. The mineral content in cortical bone is defined by the volume of dry, fat-free bone per unit bulk volume of the bone. The volumes were calculated from the bone density using the relationship between volume and density. The densities of fat and bone were taken to be 0.95 g.cm -3 and 1.92 g.cm -3 respectively. The correlation of the measured absorption coefficient with the mineral content in the samples was then

MicroCT evaluation of bone mineral density loss in human bones

Energy Technology Data Exchange (ETDEWEB)

Nogueira, Liebert P.; Braz, Delson; Lopes, Ricardo T. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Lab. de Instrumentacao Nuclear]. E-mails: lnogueira@con.ufrj.br; Barroso, Regina C.; Oliveira, Luis F. [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil). Inst. de Fisica]. E-mail: cely@uerj.br

2007-07-01

Bone is a connective tissue largely composed of an organic protein, collagen and the inorganic mineral hydroxyapatite [Ca{sub 10}(PO{sub 4}){sub 6}OH{sub 2}], which combine to provide a mechanical and supportive role in the body. Depending on the orientation of collagen fibers, two types of bone can be distinguished: trabecular and cortical bone. Degree of mineralization is considered an important feature of bone quality. Changes in the degree of mineralization is generally due to osteoporosis, but many recent studies have already shown that alterations in degree of mineralization can occur due to a large variety of factors. The transmission X-ray microtomography is one of the most popular methods, which provides the spatial distribution of the total absorption coefficient inside the sample. The aim of this study was to investigate the suitability of using microCT as a supplementary tool for the diagnosis of the health status of human bones. Eleven samples were constructed simulating the physiological range of bone mineral density (BMD) found in cortical human bone. The samples represent healthy mixtures of swine compact bone dried at room temperature, powdered and mixed with fat (0 - 100 % by mass). The samples were imaged by a microfocus tube (Fein-Focus) with focal size of about 60 {mu}m ({+-}5%), and a CCD camera (0.143 mm pixel size) coupled with an intensifier tube with fluoroscope screen at the Nuclear Instrumentation Laboratory (COPPE/UFRJ), Brazil. The images were reconstructed and treated with suitable software developed at the Nuclear Instrumentation Laboratory. The mineral content in cortical bone is defined by the volume of dry, fat-free bone per unit bulk volume of the bone. The volumes were calculated from the bone density using the relationship between volume and density. The densities of fat and bone were taken to be 0.95 g.cm{sup -3} and 1.92 g.cm{sup -3} respectively. The correlation of the measured absorption coefficient with the mineral content

X-ray and CT findings of soft tissue and bone infections secondary to acquired immunodeficiency syndrome

International Nuclear Information System (INIS)

Jiang Songfeng; Liu Jinxin; Chen Bihua; Zhang Lieguang; Gan Qingxin; Huang Deyang

2011-01-01

Objective: To summarize X-ray and CT findings of soft tissue and bone infections secondary to acquired immunodeficiency syndrome (AIDS). Methods: The data of X-ray and CT findings of soft tissue and bone infections in 18 patients with AIDS were retrospectively collected and analyzed. Results: Of 18 patients with AIDS, the CT features of soft tissue demonstrated that subcutaneous patchy high density in 1 case which considered as cellulitis, round low density lesions with ring enhancement in 6 cases which considered as soft tissue abscesses, heterogeneous density lesions with peripheral enhancement in 1 case which considered as pyomyositis. Of 18 patients with AIDS, septic arthritis was found in 4 cases involving knee lesion in 3 cases and hip lesion. In the 4 case, the X-ray films showed bony destruction in 2 cases and the CT showed bone destruction in 3 cases and arthroedema in 4 cases. Of 18 patients with AIDS, osteomyelitis was found in 9 cases of which tuberculosis was considered in. 8 cases and vertebral involvement in 6 cases. In the 9 cases, the X-ray films and CT displayed bony destruction, hyperostosis, small sequestra, and intervertebral space narrowing. Of 18 patients with AIDS, costal lesions were found in 3 cases in which the CT showed expandable bony destruction. Of 18 patients with AIDS, ilium and sacroiliac joint lesions were found in 1 case in which the X-ray films and CT showed bony destruction, sequestra, and joint widening. Of 18 patients with AIDS, chronic pyogenic osteomyelitis of femur was found in 1 case in which the X-ray films showed bony destruction, hyperostosis osteosclerosis, and periosteal reaction. Conclusion: The X-ray and CT features of soft tissue and bone infections secondary to AIDS are characterized. The X-ray and CT are useful tools to early diagnose soft tissue and bone infections secondary to AIDS. (authors)

Digital subtraction angiography in patients with central vertigo

International Nuclear Information System (INIS)

Inamori, Toru; Takayasu, Yukio; Umetani, Yoshio; Taruoka, Akinori.

1985-01-01

Digital subtraction angiography (DSA) is a recently developed non-invasive intravenous angiography which has become possible through real time digital subtraction of x-ray transmission data from an image intensifier and television system. The output signals of the image intensifier-television camera system are digitized by an analog-digital converter. The digital information, 512x512 pixels and 9 bits deep, is fed into the image processing assembly after logarithmic amplification, where 2-8 frames are added and subtracted from mask images for the final digital images. Intravenous digital subtraction angiography was performed in 21 patients with intractable dizzy spells of central origin resistant to treatment. These patients showed some signs of CNS disturbance, although there were no significant findings on CT scans. Surprisingly, findings were abnormal in 14 of 21 patients (66.7%). DSA is, therefore, considered to be an important aid in the diagnosis of vertigo of the central type. (J.P.N.)

Temporal subtraction of dual-energy chest radiographs

International Nuclear Information System (INIS)

Armato, Samuel G. III; Doshi, Devang J.; Engelmann, Roger; Caligiuri, Philip; MacMahon, Heber

2006-01-01

Temporal subtraction and dual-energy imaging are two enhanced radiography techniques that are receiving increased attention in chest radiography. Temporal subtraction is an image processing technique that facilitates the visualization of pathologic change across serial chest radiographic images acquired from the same patient; dual-energy imaging exploits the differential relative attenuation of x-ray photons exhibited by soft-tissue and bony structures at different x-ray energies to generate a pair of images that accentuate those structures. Although temporal subtraction images provide a powerful mechanism for enhancing visualization of subtle change, misregistration artifacts in these images can mimic or obscure abnormalities. The purpose of this study was to evaluate whether dual-energy imaging could improve the quality of temporal subtraction images. Temporal subtraction images were generated from 100 pairs of temporally sequential standard radiographic chest images and from the corresponding 100 pairs of dual-energy, soft-tissue radiographic images. The registration accuracy demonstrated in the resulting temporal subtraction images was evaluated subjectively by two radiologists. The registration accuracy of the soft-tissue-based temporal subtraction images was rated superior to that of the conventional temporal subtraction images. Registration accuracy also was evaluated objectively through an automated method, which achieved an area-under-the-ROC-curve value of 0.92 in the distinction between temporal subtraction images that demonstrated clinically acceptable and clinically unacceptable registration accuracy. By combining dual-energy soft-tissue images with temporal subtraction, misregistration artifacts can be reduced and superior image quality can be obtained

Standardised uptake values from PET/CT images: comparison with conventional attenuation-corrected PET

International Nuclear Information System (INIS)

Souvatzoglou, M.; Ziegler, S.I.; Martinez, M.J.; Dzewas, G.; Schwaiger, M.; Bengel, F.; Busch, R.

2007-01-01

In PET/CT, CT-derived attenuation factors may influence standardised uptake values (SUVs) in tumour lesions and organs when compared with stand-alone PET. Therefore, we compared PET/CT-derived SUVs intra-individually in various organs and tumour lesions with stand-alone PET-derived SUVs. Thirty-five patients with known or suspected cancer were prospectively included. Sixteen patients underwent FDG PET using an ECAT HR+scanner, and subsequently a second scan using a Biograph Sensation 16PET/CT scanner. Nineteen patients were scanned in the reverse order. All images were reconstructed with an iterative algorithm (OSEM). Suspected lesions were grouped as paradiaphragmatic versus distant from the diaphragm. Mean and maximum SUVs were also calculated for brain, lung, liver, spleen and vertebral bone. The attenuation coefficients (μ values) used for correction of emission data (bone, soft tissue, lung) in the two data sets were determined. A body phantom containing six hot spheres and one cold cylinder was measured using the same protocol as in patients. Forty-six lesions were identified. There was a significant correlation of maximum and mean SUVs derived from PET and PET/CT for 14 paradiaphragmatic lesions (r=0.97 respectively; p<0.001 respectively) and for 32 lesions located distant from the diaphragm (r=0.87 and r=0.89 respectively; p<0.001 respectively). No significant differences were observed in the SUVs calculated with PET and PET/CT in the lesions or in the organs. In the phantom, radioactivity concentration in spheres calculated from PET and from PET/CT correlated significantly (r=0.99; p<0.001). SUVs of cancer lesions and normal organs were comparable between PET and PET/CT, supporting the usefulness of PET/CT-derived SUVs for quantification of tumour metabolism. (orig.)

Dynamic gadolinium-enhanced subtraction MR imaging - a simple technique for the early diagnosis of Legg-Calve-Perthes disease: preliminary results

International Nuclear Information System (INIS)

Sebag, G.; Ducou Le Pointe, H.; Klein, I.; Maiza, D.; Mazda, K.; Bensahel, H.; Hassan, M.

1997-01-01

To determine whether the simple technique of dynamic gadolinium-enhanced subtraction MR imaging, which is available on standard MR units, can detect ischemia of the femoral head in children with early Legg-Calve-Perthes disease (LCP). Bone perfusion of eight hips in four patients (mean age 7.5 years) was studied using dynamic gadolinium-enhanced substraction MR imaging at the onset of proven LCP (with initial negative plain films). Enhancement of subtracted images was compared with that on standard MR images and with bone scintigraphy findings. Subtraction MR imaging depicted ischemia as a widespread absence of enhancement and was in good agreement with bone scintigraphy. The subtraction technique improved the sensitivity and the specificity of MR imaging in two children. Furthermore, subtraction MR imaging allowed recognition of the pattern of early reperfusion. Our preliminary results indicate that dynamic gadolinium-enhanced subtraction MRI is a simple and promising means of early recognition of ischemia in LCP. (orig.)

Importance of SPECT/CT for knee and hip joint prostheses; Stellenwert der SPECT/CT bei Knie- und Hueftgelenkprothesen

Energy Technology Data Exchange (ETDEWEB)

Strobel, K.; Steurer-Dober, I.; Huellner, M.W.; Veit-Haibach, P.; Allgayer, B. [Luzerner Kantonsspital (Switzerland). Institut fuer Nuklearmedizin und Roentgendiagnostik

2012-07-15

Complications, such as loosening or infections are common problems after hip or knee arthroplasty. If conventional X-rays are equivocal bone scintigraphy is the classical second-line imaging modality. Single photon emission computed tomography/computed tomography (SPECT/CT) offers metabolic and morphologic information in one imaging step and is becoming increasingly more available in larger hospitals. The SPECT/CT procedure is a promising method and is increasingly being used in daily routine to evaluate joint arthroplasty. The additional benefit compared with classical conventional bone scintigraphy has to be evaluated in further prospective studies. In our hospital SPECT/CT regularly gives important additional information regarding prosthetic joint complications. SPECT/CT is increasingly being used as the second step imaging standard modality if conventional X-rays are equivocal. (orig.) [German] Komplikationen wie Lockerung und Infekt stellen ein haeufiges Problem nach Hueft- und Kniegelenkprothesen dar. Wenn die konventionelle Roentgenaufnahme nicht zum Ziel fuehrt, ist die klassische konventionelle Skelettszintigraphie die am haeufigsten verwendete ''Second-line''-Bildgebung. Die ''single photon emission computed tomography''/CT (SPECT/CT) bietet metabolische und morphologische Informationen bzgl. Prothesenkomplikationen in einem Untersuchungsgang und ist zunehmend in groesseren Kliniken verfuegbar. Die SPECT/CT ist eine viel versprechende Methode und wird im klinischen Alltag bei der Evaluation von Gelenkprothesen zunehmend eingesetzt. Es sind noch mehr prospektive Studien noetig, um die Leistungsfaehigkeit und den Zusatznutzen gegenueber der klassischen Szintigraphie zu evaluieren. In unserer Klinik wird die Knochenszintigraphie bei der Abklaerung von Prothesenkomplikationen zumeist mit einer SPECT/CT kombiniert und liefert regelmaessig wichtige Zusatzinformationen. Die SPECT/CT entwickelt sich zunehmend zum Standard

Temporal bone trauma: correlative study between CT findings and clinical manifestations

Energy Technology Data Exchange (ETDEWEB)

Kim, Jung Hee; Kim, Hyung Jin; Kim, Jae Hyoung [College of Medicine, Gyeongsang National University, Jinju (Korea, Republic of)

1994-11-15

To assess how accurately computed tomography (CT) can demonstrate the abnormal findings which are believed to cause the clinical signs and symptoms of hearing loss (HL), vertigo and facial paralysis (FP) in patients with temporal bone trauma. The authors studied CT scans of 39 ears in 35 patients with temporal bone trauma. CT scans were performed with 1-1.5 mm slice thickness and table incrementation. Both axial and coronal scans were obtained in 32 patients and in three patients only axial scans were obtained. We analyzed CT with special reference to the structural abnormalities of the external auditory canal, middle ear cavity, bony labyrinth, and facial nerve canal, and correlated these findings with the actual clinical signs and symptoms. As to hearing loss, we evaluated 32 ears in which pure tone audiometry or brainstem evoked response audiometry had been performed. With respect to the specific types of HL, CT accurately showed the abnormalities in 84% (16/19) in conductive HL, 100% (2/2) in sensorineural HL, and 25% (2/8) for mixed HL. When we categorized HL simply as conductive and sensorineural, assuming that mixed be the result of combined conductive and sensorineural HL, CT demonstrated the abnormalities in 89% (24/27) for conductive HL and 50% (5/10) for sensorineural HL. Concerning vertigo and FP, CT demonstrated abnormalities in 67%(4/6), and 29% (4/14), respectively. Except for conductive HL, CT seems to have a variable degree of limitation for the demonstration of the structural abnormalities resulting sensorineural HL, vertigo or facial paralysis. It is imperative to correlate the CT findings with the signs and symptoms in those clinical settings.

Temporal bone trauma: correlative study between CT findings and clinical manifestations

International Nuclear Information System (INIS)

Kim, Jung Hee; Kim, Hyung Jin; Kim, Jae Hyoung

1994-01-01

To assess how accurately computed tomography (CT) can demonstrate the abnormal findings which are believed to cause the clinical signs and symptoms of hearing loss (HL), vertigo and facial paralysis (FP) in patients with temporal bone trauma. The authors studied CT scans of 39 ears in 35 patients with temporal bone trauma. CT scans were performed with 1-1.5 mm slice thickness and table incrementation. Both axial and coronal scans were obtained in 32 patients and in three patients only axial scans were obtained. We analyzed CT with special reference to the structural abnormalities of the external auditory canal, middle ear cavity, bony labyrinth, and facial nerve canal, and correlated these findings with the actual clinical signs and symptoms. As to hearing loss, we evaluated 32 ears in which pure tone audiometry or brainstem evoked response audiometry had been performed. With respect to the specific types of HL, CT accurately showed the abnormalities in 84% (16/19) in conductive HL, 100% (2/2) in sensorineural HL, and 25% (2/8) for mixed HL. When we categorized HL simply as conductive and sensorineural, assuming that mixed be the result of combined conductive and sensorineural HL, CT demonstrated the abnormalities in 89% (24/27) for conductive HL and 50% (5/10) for sensorineural HL. Concerning vertigo and FP, CT demonstrated abnormalities in 67%(4/6), and 29% (4/14), respectively. Except for conductive HL, CT seems to have a variable degree of limitation for the demonstration of the structural abnormalities resulting sensorineural HL, vertigo or facial paralysis. It is imperative to correlate the CT findings with the signs and symptoms in those clinical settings

Diagnostic test accuracy study of 18F-sodium fluoride PET/CT, 99mTc-labelled diphosphonate SPECT/CT, and planar bone scintigraphy for diagnosis of bone metastases in newly diagnosed, high-risk prostate cancer

DEFF Research Database (Denmark)

Fonager, Randi F; Zacho, Helle D; Langkilde, Niels C

2017-01-01

The aim of this study was to prospectively compare planar, bone scan (BS) versus SPECT/CT and NaF PET/CT in detecting bone metastases in prostate cancer. Thirty-seven consecutive, newly diagnosed, prostate cancer patients with prostate specific antigen (PSA) levels ≥ 50 ng/mL and who were...... considered eligible for androgen-deprivation therapy (ADT) were included in this study. BS, SPECT/CT, and NaF PET/CT, were performed prior to treatment and were repeated after six months of ADT. Baseline images from each index test were independently read by two experienced readers. The reference standard......%, and 96%, respectively, and the negative predictive values were 60%, 77% and 75%, respectively. No statistically significant difference among the three imaging modalities was observed. All three imaging modalities showed high sensitivity and specificity. NaF PET/CT and SPECT/CT showed numerically improved...

Clinical applications of SPECT/CT in imaging the extremities

International Nuclear Information System (INIS)

Huellner, Martin W.; Strobel, Klaus

2014-01-01

Today, SPECT/CT is increasingly used and available in the majority of larger nuclear medicine departments. Several applications of SPECT/CT as a supplement to or replacement for traditional conventional bone scintigraphy have been established in recent years. SPECT/CT of the upper and lower extremities is valuable in many conditions with abnormal bone turnover due to trauma, inflammation, infection, degeneration or tumour. SPECT/CT is often used in patients if conventional radiographs are insufficient, if MR image quality is impaired due to metal implants or in patients with contraindications to MR. In complex joints such as those in the foot and wrist, SPECT/CT provides exact anatomical correlation of pathological uptake. In many cases SPECT increases the sensitivity and CT the specificity of the study, increasing confidence in the final diagnosis compared to planar images alone. The CT protocol should be adapted to the clinical question and may vary from very low-dose (e.g. attenuation correction only), to low-dose for anatomical correlation, to normal-dose protocols enabling precise anatomical resolution. The aim of this review is to give an overview of SPECT/CT imaging of the extremities with a focus on the hand and wrist, knee and foot, and for evaluation of patients after joint arthroplasty. (orig.)

Clinical applications of SPECT/CT in imaging the extremities

Energy Technology Data Exchange (ETDEWEB)

Huellner, Martin W. [University Hospital Zurich, Department of Medical Radiology, Division of Nuclear Medicine, Zurich (Switzerland); Strobel, Klaus [Lucerne Cantonal Hospital, Department of Nuclear Medicine and Radiology, Lucerne (Switzerland)

2014-05-15

Today, SPECT/CT is increasingly used and available in the majority of larger nuclear medicine departments. Several applications of SPECT/CT as a supplement to or replacement for traditional conventional bone scintigraphy have been established in recent years. SPECT/CT of the upper and lower extremities is valuable in many conditions with abnormal bone turnover due to trauma, inflammation, infection, degeneration or tumour. SPECT/CT is often used in patients if conventional radiographs are insufficient, if MR image quality is impaired due to metal implants or in patients with contraindications to MR. In complex joints such as those in the foot and wrist, SPECT/CT provides exact anatomical correlation of pathological uptake. In many cases SPECT increases the sensitivity and CT the specificity of the study, increasing confidence in the final diagnosis compared to planar images alone. The CT protocol should be adapted to the clinical question and may vary from very low-dose (e.g. attenuation correction only), to low-dose for anatomical correlation, to normal-dose protocols enabling precise anatomical resolution. The aim of this review is to give an overview of SPECT/CT imaging of the extremities with a focus on the hand and wrist, knee and foot, and for evaluation of patients after joint arthroplasty. (orig.)

Accuracy of bone SPECT/CT for identifying hardware loosening in patients who underwent lumbar fusion with pedicle screws

Energy Technology Data Exchange (ETDEWEB)

Hudyana, Hendrah; Maes, Alex [AZ Groeninge, Department of Nuclear Medicine, Kortrijk (Belgium); University Hospital Leuven, Department of Morphology and Medical Imaging, Leuven (Belgium); Vandenberghe, Thierry; Fidlers, Luc [AZ Groeninge, Department of Neurosurgery, Kortrijk (Belgium); Sathekge, Mike [University of Pretoria, Department of Nuclear Medicine, Pretoria (South Africa); Nicolai, Daniel [AZ Groeninge, Department of Nuclear Medicine, Kortrijk (Belgium); Wiele, Christophe van de [AZ Groeninge, Department of Nuclear Medicine, Kortrijk (Belgium); University Ghent, Department of Radiology and Nuclear Medicine, Ghent (Belgium)

2016-02-15

The aim of this retrospective study was to evaluate the accuracy of bone SPECT (single photon emission computed tomography)/CT (computed tomography) in diagnosing loosening of fixation material in patients with recurrent or persistent back pain that underwent lumbar arthrodesis with pedicle screws using surgery and clinical follow-up as gold standard A total of 48 patients (median age 49 years, range 21-81 years; 17 men) who had undergone lumbar spinal arthrodesis were included in this retrospective analysis. SPECT/CT results were compared to the gold standard of surgical evaluation or clinical follow-up. Positive SPECT/CT results were considered true positives if findings were confirmed by surgery or if clinical and other examinations were completely consistent with the positive SPECT/CT finding. They were considered false positives if surgical evaluation did not find any loose pedicle screws or if symptoms subsided with non-surgical therapy. Negative SPECT/CT scans were considered true negatives if symptoms either improved without surgical intervention or remained stable over a minimum follow-up period of 6 months. Negative SPECT/CT scans were determined to be false negatives if surgery was still required and loosening of material was found. The median length of time from primary surgery to bone SPECT/CT referral was 29.5 months (range 12-192 months). Median follow-up was 18 months (range 6-57) for subjects who did not undergo surgery. Thirteen of the 48 patients were found to be positive for loosening on bone SPECT/CT. Surgical evaluation (8 patients) and clinical follow-up (5 patients) showed that bone SPECT/CT correctly predicted loosening in 9 of 13 patients, while it falsely diagnosed loosening in 4 patients. Of 35 negative bone SPECT/CT scans, 12 were surgically confirmed. In 18 patients, bone SPECT/CT revealed lesions that could provide an alternative explanation for the symptoms of pain (active facet degeneration in 14 patients, and disc and sacroiliac

Bone bruise, lipohemarthrosis, and joint effusion in CT of non-displaced hip fracture

International Nuclear Information System (INIS)

Geijer, Mats; Dunker, Dennis; Collin, David; Goethlin, Jan H.

2012-01-01

Background. A suspected occult hip fracture after normal radiography is not uncommon in an elderly person after a fall. Despite a lack of robust validation in the literature, computed tomography (CT) is often used as secondary imaging. Purpose. To assess the frequency and clinical utility of non-cortical skeletal and soft tissue lesions as ancillary fracture signs in CT diagnosis of occult hip fractures. Material and Methods. All fracture signs (cortical and trabecular fractures, bone bruise, joint effusion, and lipohemarthrosis) were recorded in 231 hip low-energy trauma cases with CT performed after normal or equivocal radiography in two trauma centers. Results. There were no fracture signs in 110 patients. Twelve of these had a joint effusion. In 121 patients with 46 cervical hip fractures and 75 trochanteric fractures one or more fracture signs were present. Cortical fractures were found in 115 patients. Bone bruise was found in 119 patients, joint effusion in 35, and lipohemarthrosis in 20 patients. Conclusion. Ancillary signs such as bone bruise and lipohemarthrosis can strengthen and sometimes indicate the diagnosis in CT of occult hip fractures. Joint effusion is a non-specific sign

Bone bruise, lipohemarthrosis, and joint effusion in CT of non-displaced hip fracture

Energy Technology Data Exchange (ETDEWEB)

Geijer, Mats (Center for Medical Imaging and Physiology, Skaane University Hospital, Lund University, Lund (Sweden)), Email: mats@geijer.info; Dunker, Dennis; Collin, David; Goethlin, Jan H. (Department of Radiology, Sahlgrenska University Hospital, Moelndal (Sweden))

2012-03-15

Background. A suspected occult hip fracture after normal radiography is not uncommon in an elderly person after a fall. Despite a lack of robust validation in the literature, computed tomography (CT) is often used as secondary imaging. Purpose. To assess the frequency and clinical utility of non-cortical skeletal and soft tissue lesions as ancillary fracture signs in CT diagnosis of occult hip fractures. Material and Methods. All fracture signs (cortical and trabecular fractures, bone bruise, joint effusion, and lipohemarthrosis) were recorded in 231 hip low-energy trauma cases with CT performed after normal or equivocal radiography in two trauma centers. Results. There were no fracture signs in 110 patients. Twelve of these had a joint effusion. In 121 patients with 46 cervical hip fractures and 75 trochanteric fractures one or more fracture signs were present. Cortical fractures were found in 115 patients. Bone bruise was found in 119 patients, joint effusion in 35, and lipohemarthrosis in 20 patients. Conclusion. Ancillary signs such as bone bruise and lipohemarthrosis can strengthen and sometimes indicate the diagnosis in CT of occult hip fractures. Joint effusion is a non-specific sign

Maximum-intensity-projection CT angiography for evaluating head and neck tumors. Usefulness of helical CT and auto bone masking method

International Nuclear Information System (INIS)

Sakai, Osamu; Nakashima, Noriko; Ogawa, Chiaki; Shen, Yun; Takata, Yasunori; Azemoto, Shougo.

1994-01-01

Angiographic images of 10 adult patients with head and neck tumors were obtained by helical computed tomography (CT) using maximum intensity projection (MIP). In all cases, the vasculature of the head and neck region was directly demonstrated. In the head and neck, bone masking is a more important problem than in other regions. We developed an effective automatic bone masking method (ABM) using 2D/3D connectivity. Helical CT angiography with MIP and ABM provided accurate anatomic depiction, and was considered to be helpful in preoperative evaluation of head and neck tumors. (author)

Characterizing bone marrow involvement in Hodgkin's lymphoma by FDG-PET/CT

International Nuclear Information System (INIS)

Weiler-Sagie, Michal; Kagna, Olga; Dann, Eldad J.; Ben-Barak, Ayelet; Israel, Ora

2014-01-01

Fluoro-deoxyglucose positron emission tomography combined with computed tomography (FDG-PET/CT) is superior to iliac bone marrow biopsy (iBMB) for detection of bone marrow involvement (BMI) in staging of Hodgkin's lymphoma (HL). The present study aims to characterize the patterns and distribution of BMI in HL as determined by FDG-PET/CT. Reports of FDG-PET/CT studies performed for staging of HL were reviewed. BMI was defined as positive iBMB and/or foci of pathological FDG uptake in the skeleton that behaved in concordance with other sites of lymphoma in studies following chemotherapy. Number of FDG uptake foci, their specific location in the skeleton and the presence of corresponding lesions in the CT component of the study, and stage according to the Ann Arbor staging system, were recorded. The study included 473 patients. iBMB was performed in 336 patients. Nine patients had positive iBMB (9/336, 3 %). Seventy-three patients (73/473, 15 %) had FDG-PET/CT-defined BMI. The BM was the only extranodal site of HL in 52/473 patients (11 %). Forty-five patients had three or more foci of pathological skeletal FDG uptake (45/73, 62 %). Sixty-four patients (64/73, 88 %) had at least one uptake focus in the pelvis or vertebrae. In 60 patients (60/73, 82 %), the number of skeletal FDG uptake foci without corresponding CT lesions was equal to or higher than the number of foci with morphological abnormalities. FDG-PET/CT demonstrated BMI in 15 % of patients with newly diagnosed HL. Diagnosis of BMI in HL by FDG-PET/CT was more sensitive than iBMB with potential upstage in 11 % of patients. The most common pattern of FDG-PET/CT BMI was multifocal (at least three foci) skeletal FDG uptake, with at least one focus in the pelvis or vertebrae and no corresponding CT lesions. (orig.)

A technique for developing CAD geometry of long bones using clinical CT data.

Science.gov (United States)

Davis, Matthew L; Vavalle, Nicholas A; Stitzel, Joel D; Gayzik, F Scott

2015-11-01

Computed tomography scans are a valuable tool for developing computational models of bones. The objective of this study is to present a method to generate CAD representations of long bones from clinically based CT scans. A secondary aim is to apply the method to six long bones from a sample of three individuals. Periosteal and endosteal bone surfaces were segmented and used to calculate the characteristic cortical thickness, Tc, at 1 mm increments along the bone axis. In the epiphyses where the value of Tc fell below the scanner threshold, the endosteal bone layer was replaced using literature values projected inward from the periosteal surface. On average, 74.7 ± 7.4% of the bone geometry was above the scanner cut-off and was therefore derived from the CT scan data. The thickness measurement was also compared to experimental measurements of cadaveric bone and was found to predict Tc with an error of 3.1%. This method presents a possible solution for the characterization of characteristic thickness along the length of the bone and may also aid in the development of orthopedic implant design and subject specific finite element models. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

Factors influencing diagnostic yield of CT-guided percutaneous core needle biopsy for bone lesions

International Nuclear Information System (INIS)

Li, Y.; Du, Y.; Luo, T.Y.; Yang, H.F.; Yu, J.H.; Xu, X.X.; Zheng, H.J.; Li, B.

2014-01-01

Aim: To evaluate the factors influencing diagnostic yield of computed tomography (CT)-guided percutaneous core needle biopsy (CNB) for bone lesions. Materials and methods: Between September 2005 and July 2011, 162 consecutive CT-guided CNB procedures were performed in 155 patients. The variables analysed were age, sex, lesion location, lesion type, lesion size, specimen size, biopsy needle gauge, and individual radiologist. The factors influencing diagnostic yield of CT-guided percutaneous CNB for bone lesions were determined by multivariate analysis of variables. Results: The diagnostic yield was 81.5%. Diagnostic yield was 89.9% for lytic bone lesions and 48.5% for sclerotic bone lesions (p < 0.001), and 89.2% for lesions ≥3 cm and 73.4% for lesions <3 cm (p = 0.010). The significant factors influencing diagnostic yield of CT-guided percutaneous CNB for bone lesions were lesion type [p < 0.001; odds ratio (OR) for a lytic lesion was approximately 12 times higher than that for a sclerotic lesion; 95% confidence interval (CI): 4.22–34.01], and lesion size (p = 0.012; OR for a lesion size ≥3 cm was about five-times higher than that for a lesion size <3 cm; 95% CI: 1.42–16.71). Conclusion: Lesion type and lesion size are determining factors in diagnostic yield. The higher diagnostic yield is correlated with lytic lesion and lesion size ≥3 cm

Restoration of Thickness, Density, and Volume for Highly Blurred Thin Cortical Bones in Clinical CT Images.

Science.gov (United States)

Pakdel, Amirreza; Hardisty, Michael; Fialkov, Jeffrey; Whyne, Cari

2016-11-01

In clinical CT images containing thin osseous structures, accurate definition of the geometry and density is limited by the scanner's resolution and radiation dose. This study presents and validates a practical methodology for restoring information about thin bone structure by volumetric deblurring of images. The methodology involves 2 steps: a phantom-free, post-reconstruction estimation of the 3D point spread function (PSF) from CT data sets, followed by iterative deconvolution using the PSF estimate. Performance of 5 iterative deconvolution algorithms, blind, Richardson-Lucy (standard, plus Total Variation versions), modified residual norm steepest descent (MRNSD), and Conjugate Gradient Least-Squares were evaluated using CT scans of synthetic cortical bone phantoms. The MRNSD algorithm resulted in the highest relative deblurring performance as assessed by a cortical bone thickness error (0.18 mm) and intensity error (150 HU), and was subsequently applied on a CT image of a cadaveric skull. Performance was compared against micro-CT images of the excised thin cortical bone samples from the skull (average thickness 1.08 ± 0.77 mm). Error in quantitative measurements made from the deblurred images was reduced 82% (p < 0.01) for cortical thickness and 55% (p < 0.01) for bone mineral mass. These results demonstrate a significant restoration of geometrical and radiological density information derived for thin osseous features.

CT findings of a unicameral calcaneal bone cyst containing a fluid-fluid level.

Science.gov (United States)

Gallagher, Thomas A; Lim-Dunham, Jennifer E; Vade, Aruna

2007-03-01

Calcaneal unicameral bone cysts often contain fluid, but rarely contain fluid-fluid levels. We present a case focusing on the CT findings of a large calcaneal bone cyst with a fluid-fluid level and a review of the literature.

SU-F-R-55: Early Detection of Treatment Induced Bone Marrow Injury During Chemoradiation Therapy Using Quantitative CT

Energy Technology Data Exchange (ETDEWEB)

Chen, X; Song, Y; Erickson, B; Li, X [Medical College of Wisconsin, Milwaukee, WI (United States)

2016-06-15

Purpose: Acute hematologic toxicity associated with bone marrow injury is a common complication of chemoradiation therapy (CRT) for pelvic malignancies. In this work, we investigate the feasibility of using quantitative CT to detect bone marrow injury during CRT. Methods: Daily CTs were acquired during routine CT-guided radiation therapy using a CT-on-rails for 15 cervical cancer patients. All patients treated with a radiation dose of 45.0 to 50.4 Gy in 1.8 Gy/fraction along with chemotherapy. For each patient, the contours of bone marrow were generated in L4, L5 and sacrum on the first daily CT and then populated to other daily CTs by rigid registration using MIM (MIM Software Inc., Cleveland, OH) with manual editing if possible. A series of CT texture parameters, including Hunsfield Unit (HU) histogram, mean HU, entropy, energy, in bone marrow contours were calculated using MATLAB on each daily CT and were correlated with the completed blood counts (CBC) collected weekly for each patient. The correlations were analyzed with Pearson correlation tests. Results: For all patient data analyzed, mean HU in bone marrow decreased during CRT delivery. From the first to the last fraction the average mean HU reduction is 58.1 ± 13.6 HU (P<0.01). This decrease can be observed as early as after first 5 fractions and is strongly associated with the changes of most CBC quantities, such as the reductions of white and blood cell counts (r=0.97, P=0.001). The reduction of HU is spatially varied. Conclusion: Chemoradiation induced bone marrow injury can be detected during the delivery of CRT using quantitative CT. Chemoradiation results in reductions in mean HU, which are strongly associated with the change in the pretrial blood cell counts. Early detection of bone marrow injury with commonly available CT opens a door to improve bone marrow sparing, reducing risk of hematologic toxicity.

Observation of femoral and tibial insertion of the posterior cruciate ligament by using conventional CT and transparent 3D-CT

International Nuclear Information System (INIS)

Inoue, Masayuki; Tsukuda, Koichiro; Yasojima, Nobutoshi; Oota, Masahiro; Kasahara, Yasuhiko

2011-01-01

Presented are image data acquisitioned by the volume rendering (VR)-3D-CT and authors' transparent (T)-3D-CT to depict the bone contour, of medial intercondylar ridge (MIR) and posterior intercodylar fossa (PIF) at femoral and tibial insertion, respectively, of the posterior cruciate ligament (PCL) as those data are helpful for planning the reconstruction surgery of PCL and for confirming the femoral PCL insertion by using the C-arm during operation. Helical scanning is conducted with GE MD-CT (64DAS) to reconstruct VR-3D-CT image with the workstation ZIO's ZIO900M Quadra and T-3D-CT image, by reducing the opacity by pixel exclusion of the intraosseous lumen. MIR is observed in all 70 normal knees tested in VR-3D-CT and the bifurcate ridge, in 15 knees among them. In T-3D-CT image, distance data of the origin of MIR from Blumensaat's line and the angle of MIR and bone axis are calculated and presented. In VR-3D-CT and T-3D-CT images of PIF from 20 knees, actual measures of PIF slope angle (degree), PIF area ratio to joint surface (JS) (%), distance from JS to centers of anterolateral (AL) and posterolateral (PM) slopes (mm), and from medial and lateral JS to PIF posterior border (mm), and distance ratios of PM and AL to medial and lateral tibia, respectively, (%) are calculated and presented. Findings are: MIR originates at 45% distal point of Blumensaat's line; the articular line crosses with PIF at its center in T-3D-CT sagittal plane; centers of tibial AL and PM exist at the middle of frontal plane, and at 1.00 and 5.5 mm, respectively, distal points of JS of sagittal plane. The PIF data are rather comparable to those obtained in cadavers reported in 3 literatures and the present procedure is concluded to be valid. (author)

Creation of a 3D printed temporal bone model from clinical CT data.

Science.gov (United States)

Cohen, Joss; Reyes, Samuel A

2015-01-01

Generate and describe the process of creating a 3D printed, rapid prototype temporal bone model from clinical quality CT images. We describe a technique to create an accurate, alterable, and reproducible rapid prototype temporal bone model using freely available software to segment clinical CT data and generate three different 3D models composed of ABS plastic. Each model was evaluated based on the appearance and size of anatomical structures and response to surgical drilling. Mastoid air cells had retained scaffolding material in the initial versions. This required modifying the model to allow drainage of the scaffolding material. External auditory canal dimensions were similar to those measured from the clinical data. Malleus, incus, oval window, round window, promontory, horizontal semicircular canal, and mastoid segment of the facial nerve canal were identified in all models. The stapes was only partially formed in two models and absent in the third. Qualitative feel of the ABS plastic was softer than bone. The pate produced by drilling was similar to bone dust when appropriate irrigation was used. We present a rapid prototype temporal bone model made based on clinical CT data using 3D printing technology. The model can be made quickly and inexpensively enough to have potential applications for educational training. Copyright © 2015 Elsevier Inc. All rights reserved.

FDG PET and PET-CT for the detection of bone metastases in patients with head and neck cancer. A meta-analysis

International Nuclear Information System (INIS)

Yi, Xuelin; Zhang, Hongting; Liu, Shixi; Fan, Min; Liu, Yilin

2013-01-01

We performed a meta-analysis to evaluate 18FDG PET/PET-CT for the detection of bone metastases in patients with head and neck cancer. We calculated sensitivities, specificities, likelihood ratios, and constructed summary receiver operating characteristic curves for PET and PET-CT, respectively. We also compared the performance of PET/PET-CT with that of bone scintigraphy by analysing studies that had also used bone scintigraphy on the same patients. Across 9 PET studies (1621 patients) and 10 PET-CT studies (1291 patients), sensitivity and specificity of PET were 0.81 and 0.99, and of PET-CT were 0.89 and 0.99, respectively. In 5 comparative studies (1184 patients), sensitivity and specificity of PET/PET-CT were 0.85 and 0.98, and of bone scintigraphy were 0.55 and 0.98, respectively. 18FDG PET and PET-CT have high sensitivity and accuracy for the detection of bone metastasis in patients with head and neck cancer.

Detection of distant metastases in patients with locally advanced breast cancer: role of {sup 18}F-fluorodeoxyglucose positron emission tomography/computed tomography and conventional imaging with computed tomography scans

Energy Technology Data Exchange (ETDEWEB)

Bitencourt, Almir Galvao Vieira; Andrade, Wesley Pereira; Cunha, Rodrigo Rodrigues da; Conrado, Jorge Luis Fonseca de Acioli; Lima, Eduardo Nobrega Pereira; Barbosa, Paula Nicole Vieira Pinto; Chojniak, Rubens, E-mail: rodrigo.rcunha@hotmail.com [A. C. Camargo Cancer Center, Sao Paulo, SP (Brazil); Hospital Beneficincia Portuguesa de Sao Paulo, Sao Paulo, SP (Brazil)

2017-07-15

Objective: To evaluate positron emission tomography/computed tomography (PET/CT) and conventional imaging tests for the detection of distant metastases in patients with locally advanced breast cancer. Materials and Methods: We included 81 patients with breast cancer who had undergone {sup 18}-fluorodeoxyglucose (FDG) PET/CT before treatment. Conventional imaging included the following: bone scintigraphy; chest X-ray (in 14.5%) or CT (in 85.5%); and abdominal ultrasound (in 10.8%), CT (in 87.8%), or magnetic resonance imaging (in 1.4%). Histopathology and clinical/imaging follow-up served as reference. Results: Distant metastases were observed in nine patients (11.1%). On patient-based analysis, conventional imaging identified distant metastases in all 9 patients. In one patient, the initial {sup 18}F-FDG PET/CT failed to demonstrate bone metastases that was evident on bone scintigraphy. In two patients, the CT scan failed to show extra-axillary lymph node metastases that were identified on {sup 18}F-FDG PET/CT. There was no significant difference between {sup 18}F-FDG PET/CT and conventional imaging in terms of their sensitivity for the detection of distant metastases in patients with locally advanced breast cancer. Conclusion: This study showed that {sup 18}F-FDG PET/CT and conventional imaging with CT scans had similar sensitivity for the diagnosis of distant metastases in patients with locally advanced breast cancer. {sup 18}F-FDG PET/CT can add information about extra-axillary lymph node involvements. (author)

Accuracy of preoperative diagnosis for primary hyperparathyroidism by CT, US and scintigraphy

International Nuclear Information System (INIS)

Imada, Masanobu; Nonaka, Satoshi; Hayashi, Tatsuya; Kunibe, Isamu; Harabuchi, Yasuaki

2003-01-01

We determined the usefulness of computed tomography (CT), ultrasonography (US) and Tc-Tl subtraction scintigraphy for preoperative diagnosis in 12 patients with primary hyperparathyroidism, all of which were solitary adenoma. Seven (63.6%) of 11 tumors were detected by CT, 7 (58.3%) of 12 tumors were detected by US, and 7 (63.6%) of 11 tumors were detected by Tc-Tl subtraction scintigraphy. Of 7 tumors with size>10 mm, 6 (85.7%) were detected by CT, 5 (71.4%) were detected by US, and 6 (85.7%) were detected by Tc-Tl subtraction scintigraphy, whereas only 1 (25%) with a diameter of 10 mm was detected by each of CT or Tc-Tl subtraction scintigraphy and 2 (40%) with diameters 10 mm were detected by US. Of 6 tumors situated behind the thyroid gland or intra thyroid gland, 5 (83.3%) were detected by CT and all 6 (100%) were detected by US, Tl-Tc subtraction scintigraphy, which was employed for 5 tumors, detected all 5 (100%). However, in the tumors situated beneath the thyroid gland only 2 (40%) of 5, 1 (16.7%) of 6 and 2 (33.3%) of 6 were detected by CT, US and Tc-Tl subtraction scintigraphy respectively. In 5 tumors without thyroid disease, 4 (80%) of 5 were detected by both CT and US, 3 (75%) of 4 were detected by Tc-Tl subtraction scintigraphy. However, in 7 tumors with thyroid diseases (papillary carcinoma, follicular carcinoma, follicular adenoma, chronic thyroiditis, and adenomatous goiter), 3 (50%) of 6 were detected by CT, 3 (42.9%) of 7 were detected by US and 4 (57.1%) of 7 were detected by Tc-Tl subtraction scintigraphy. Location of tumor was the factor most likely to make appropriate diagnosis difficult for primary hyperparathyroidism by any assessment method. (author)

Vascular anatomy of the liver and porta hepatis with dynamic CT scan

International Nuclear Information System (INIS)

Hiramatsu, Yoshihiro; Wada, Mitsuyoshi; Nakajima, Teiichi; Tonooka, Reiko; Matsumoto, Kunihiko

1983-01-01

Vascular anatomy of the liver and porta heaptis demonstrated by dynamic CT scan was studied Identification of the individual vessels was sometimes difficult due to slight differencies in respiratory depths among the scans. Limitation in the number of slices also made the evalution of the vascular anatomy difficult. Angiography was therefore utilized for comparison in identifying the vessels. Dynamic CT scan was proved to be usefull in demonstrating the anteroposterior relationship of the vessels and surrounding structures, which is difficult with convetional angiography without multiple projections. Three dimensional understanding of the vessels was then possible with dynamic CT scan and angiography. When combined with recently advancing digital subtraction angiography, dynamic CT scan might reduce the necessity for conventional angiography with Seldinger's technique. (author)

Quantitative computed tomography for measuring bone mineral content

International Nuclear Information System (INIS)

Felsenberg, D.; Kalender, W.A.; Banzer, D.; Schmilinsky, G.; Heyse, M.; Fischer, E.; Schneider, U.; Siemens A.G., Erlangen; Krankenhaus Zehlendorf, Berlin

1988-01-01

Quantitative computed tomography (QCT) for measuring bone mineral content of lumbar vertebrae is increasingly used internationally. The effect of using conventional CT (single energy CT, SE-CT) and dual energy CT (DE-CT) on reproducibility has been examined. We defined a standard measurement protocol, which automatically evaluates a calibration phantom. This should ensure an in vivo reproducibility of 1 to 2%. Reference data, which has been obtained with this protocol from 113 normal subjects, using SE-CT ad DE-CT, are presented. (orig.) [de

Radiation doses in examination of lower third molars with computed tomography and conventional radiography.

Science.gov (United States)

Ohman, A; Kull, L; Andersson, J; Flygare, L

2008-12-01

To measure organ doses and calculate effective doses for pre-operative radiographic examination of lower third molars with CT and conventional radiography (CR). Measurements of organ doses were made on an anthropomorphic head phantom with lithium fluoride thermoluminescent dosemeters. The dosemeters were placed in regions corresponding to parotid and submandibular glands, mandibular bone, thyroid gland, skin, eye lenses and brain. The organ doses were used for the calculation of effective doses according to proposed International Commission on Radiological Protection 2005 guidelines. For the CT examination, a Siemens Somatom Plus 4 Volume Zoom was used and exposure factors were set to 120 kV and 100 mAs. For conventional radiographs, a Scanora unit was used and panoramic, posteroanterior, stereographic (scanogram) and conventional spiral tomographic views were exposed. The effective doses were 0.25 mSv, 0.060 mSv and 0.093 mSv for CT, CR without conventional tomography and CR with conventional spiral tomography, respectively. The effective dose is low when CT examination with exposure factors optimized for the examination of bone structures is performed. However, the dose is still about four times as high as for CR without tomography. CT should therefore not be a standard method for the examination of lower third molars. In cases where there is a close relationship between the tooth and the inferior alveolar nerve the advantages of true sectional imaging, such as CT, outweighs the higher effective dose and is recommended. Further reduction in the dose is feasible with further optimization of examination protocols and the development of newer techniques.

CT evaluation of primary epiphyseal bone abscesses

Energy Technology Data Exchange (ETDEWEB)

Azouz, E.M. (Dept. of Radiology, McGill Univ., Montreal Children' s Hospital, PQ (Canada)); Greenspan, A. (Dept. of Radiology, California Univ., Davis School of Medicine, Sacramento, CA (United States)); Marton, D. (Dept. of Radiology, Montreal Univ., Hopital Ste Justine, PQ (Canada))

1993-01-01

We reviewed the clinical, radiographic, and computed tomographic (CT) findings in eight children with a histologically proven diagnosis of epiphyseal or apophyseal osteomyelitis. In all cases the femur was involved: in five the osteomyelitis was localized in the femoral condyle, in two it was in the greater trochanter, and in one it was in the femoral head epiphysis. In four of the six cases of epiphyseal involvement there was associated joint effusion or septic arthritis. CT examination may demonstrate a serpentine tract, a sequestrum, cortical destruction or adjacent soft tissue swelling and can differentiate osteomyelitis from other epiphyseal lucent lesions, particularly chondroblastoma and osteoid osteoma. Early diagnosis helps avoid delays in initiating antibiotic or surgical treatment caused by the unusual (epiphyseal or apophyseal) location of the bone abscess. (orig./GD)

Accuracy of cancellous bone volume fraction measured by micro-CT scanning

DEFF Research Database (Denmark)

Ding, Ming; Odgaard, A; Hvid, I

1999-01-01

Volume fraction, the single most important parameter in describing trabecular microstructure, can easily be calculated from three-dimensional reconstructions of micro-CT images. This study sought to quantify the accuracy of this measurement. One hundred and sixty human cancellous bone specimens...... which covered a large range of volume fraction (9.8-39.8%) were produced. The specimens were micro-CT scanned, and the volume fraction based on Archimedes' principle was determined as a reference. After scanning, all micro-CT data were segmented using individual thresholds determined by the scanner...

Radiotherapy and the importance of CT for the nasopharyngeal squammous cell carcinoma, 1

International Nuclear Information System (INIS)

Yamashita, Shoji; Dokiya, Takushi.

1987-01-01

Thirty-five patients with nasopharyngeal squamous cell carcinoma (NPC) were examined with computed tomography (CT) before definitive radiotherapy. CT clearly delincated the extent of the primary tumors. CT frequently showed subtle destruction of the paranasal sinuses and pterygoid plate, which was not usually detected by conventional X-ray examinations. T-staging was made according to the UICC TNM classification system (1978), depending on the clinical findings and the conventional X-ray examinations (non-CT T-stage). Then the non-CT T-stage of each patient was compared with T-stage diagnosed with CT findings alone (CT T-stage). CT upstaged non-CT T-stage in 14 of the 35 patients. Only one patient was downstaged by CT ; this patient had cranial nerve palsy but no detectable bone destruction as shown by CT. Since CT can reveal both bones and abnormal soft tissues well, it is a very useful diagnostic tool for the staging of the tumor assessment of treatment planning. Before radiotherapy, we should use CT to confirm that whether the tumor was located within the radiation field. CT is also useful to see the tumor regression after definitive radiotherapy. We conclude that CT is the single, most reliable imaging method for primary tumors of the NPC patients. (author)

Repeatability of quantitative parameters of 18F-fluoride PET/CT and biochemical tumour and specific bone remodelling markers in prostate cancer bone metastases.

Science.gov (United States)

Wassberg, Cecilia; Lubberink, Mark; Sörensen, Jens; Johansson, Silvia

2017-12-01

18F-fluoride PET/CT exhibits high sensitivity to delineate and measure the extent of bone metastatic disease in patients with prostate cancer. 18F-fluoride PET/CT could potentially replace traditional bone scintigraphy in clinical routine and trials. However, more studies are needed to assess repeatability and biological uptake variation. The aim of this study was to perform test-retest analysis of quantitative PET-derived parameters and blood/serum bone turnover markers at the same time point. Ten patients with prostate cancer and verified bone metastases were prospectively included. All underwent two serial 18F-fluoride PET/CT at 1 h post-injection. Up to five dominant index lesions and whole-body 18F-fluoride skeletal tumour burden were recorded per patient. Lesion-based PET parameters were SUVmax, SUVmean and functional tumour volume applying a VOI with 50% threshold (FTV 50% ). The total skeletal tumour burden, total lesion 18F-fluoride (TLF), was calculated using a threshold of SUV of ≥15. Blood/serum biochemical bone turnover markers obtained at the time of each PET were PSA, ALP, S-osteocalcin, S-beta-CTx, 1CTP and BAP. A total of 47 index lesions and a range of 2-122 bone metastases per patient were evaluated. Median time between 18F-fluoride PET/CT was 7 days (range 6-8 days). Repeatability coefficients were for SUVmax 26%, SUVmean 24%, FTV 50% for index lesions 23% and total skeletal tumour burden (TLF) 35%. Biochemical bone marker repeatability coefficients were for PSA 19%, ALP 23%, S-osteocalcin 18%, S-beta-CTx 22%, 1CTP 18% and BAP 23%. Quantitative 18F-fluoride uptake and simultaneous biochemical bone markers measurements are reproducible for prostate cancer metastases and show similar magnitude in test-retest variation.

Dynamic computed tomography scanning of benign bone lesions: Preliminary results

International Nuclear Information System (INIS)

Levine, E.; Neff, J.R.

1983-01-01

The majority of benign bone lesions can be evaluated adequately using conventional radiologic techniques. However, it is not always possible to differentiate reliably between different types of benign bone lesions on the basis of plain film appearances alone. Dynamic computed tomography (CT) scanning provides a means for further characterizing such lesions by assessing their degree of vascularity. Thus, it may help in distinguishing an osteoid osteoma, which has a hypervascular nidus, from a Brodie's abscess, which is avascular. Dynamic CT scanning may also help in the differentiation between a fluid-containing simple bone cyst, which is avascular, and other solid or semi-solid benign bone lesions which slow varying degrees of vascularity. However, because of the additional irradiation involved, dynamic CT scanning should be reserved for evaluation of selected patients with benign bone lesions in whom the plain film findings are not definitive and in whom the CT findings may have a significant influence on management. (orig.)

Assessment of the increased calcification of the jaw bone with CT-Scan after dental implant placement.

Science.gov (United States)

Yunus, Barunawaty

2011-06-01

This study was performed to evaluate the changes of jaw bone density around the dental implant after placement using computed tomography scan (CT-Scan). This retrospective study consisted of 30 patients who had lost 1 posterior tooth in maxilla or mandible and installed dental implant. The patients took CT-Scan before and after implant placement. Hounsfield Unit (HU) was measured around the implants and evaluated the difference of HU before and after implant installation. The mean HU of jaw bone was 542.436 HU and 764.9 HU before and after implant placement, respectively (p<0.05). The means HUs for male were 632.3 HU and 932.2 HU and those for female 478.2 HU and 645.5 HU before and after implant placement, respectively (p<0.05). Also, the jaw bone with lower density needed longer period for implant procedure and the increased change of HU of jaw bone was less in the cases which needed longer period for osseointegration. CT-Scan could be used to assess the change of bone density around dental implants. Bone density around dental implant was increased after placement. The increased rate of bone density could be determined by the quality of jaw bone before implant placement.

Assessment of the increased calcification of the jaw bone with CT-Scan after dental implant placement

Energy Technology Data Exchange (ETDEWEB)

Yunus, Barunawaty [Faculty of Dentistry, Hasanuddin University, Makassar (Malaysia)

2011-06-15

This study was performed to evaluate the changes of jaw bone density around the dental implant after placement using computed tomography scan (CT-Scan). This retrospective study consisted of 30 patients who had lost 1 posterior tooth in maxilla or mandible and installed dental implant. The patients took CT-Scan before and after implant placement. Hounsfield Unit (HU) was measured around the implants and evaluated the difference of HU before and after implant installation. The mean HU of jaw bone was 542.436 HU and 764.9 HU before and after implant placement, respectively (p<0.05). The means HUs for male were 632.3 HU and 932.2 HU and those for female 478.2 HU and 645.5 HU before and after implant placement, respectively (p<0.05). Also, the jaw bone with lower density needed longer period for implant procedure and the increased change of HU of jaw bone was less in the cases which needed longer period for osseointegration. CT-Scan could be used to assess the change of bone density around dental implants. Bone density around dental implant was increased after placement. The increased rate of bone density could be determined by the quality of jaw bone before implant placement.

Assessment of the increased calcification of the jaw bone with CT-Scan after dental implant placement

International Nuclear Information System (INIS)

Yunus, Barunawaty

2011-01-01

This study was performed to evaluate the changes of jaw bone density around the dental implant after placement using computed tomography scan (CT-Scan). This retrospective study consisted of 30 patients who had lost 1 posterior tooth in maxilla or mandible and installed dental implant. The patients took CT-Scan before and after implant placement. Hounsfield Unit (HU) was measured around the implants and evaluated the difference of HU before and after implant installation. The mean HU of jaw bone was 542.436 HU and 764.9 HU before and after implant placement, respectively (p<0.05). The means HUs for male were 632.3 HU and 932.2 HU and those for female 478.2 HU and 645.5 HU before and after implant placement, respectively (p<0.05). Also, the jaw bone with lower density needed longer period for implant procedure and the increased change of HU of jaw bone was less in the cases which needed longer period for osseointegration. CT-Scan could be used to assess the change of bone density around dental implants. Bone density around dental implant was increased after placement. The increased rate of bone density could be determined by the quality of jaw bone before implant placement.

CT findings in tuberculous otomastoiditis. A case report

International Nuclear Information System (INIS)

Cavallin, L.; Muren, C.

2000-01-01

Otomastoiditis is a rare but important manifestation of tuberculosis and is well recognizable when information on its clinical course is considered in connection with the radiographic changes. A patient with a clinical history of chronic otorrhea, resistant to conventional therapy but without dramatic symptoms, was referred for CT examination. CT revealed widespread soft tissue densities in the tympanic cavity and in the mastoid process, with bone erosions in the latter. Surgery and bacteriology confirmed the diagnosis of Mycobacterium tuberculosis infection. CT evidence of widespread bone destruction without clinical signs of aggressive infection should suggest the diagnosis of a mycobacterial process. Early treatment is essential in order to avoid propagation of the disease and lasting loss of function

Accuracy and reliability of different cone beam computed tomography (CBCT) devices for structural analysis of alveolar bone in comparison with multislice CT and micro-CT.

Science.gov (United States)

Van Dessel, Jeroen; Nicolielo, Laura Ferreira Pinheiro; Huang, Yan; Coudyzer, Walter; Salmon, Benjamin; Lambrichts, Ivo; Jacobs, Reinhilde

The aim of this study was to assess whether cone beam computed tomography (CBCT) may be used for clinically reliable alveolar bone quality assessment in comparison to its clinical alternatives, multislice computed tomography and the gold standard (micro-CT). Six dentate mandibular bone samples were scanned with seven CBCT devices (ProMax 3D Max, NewTom GiANO, Cranex 3D, 3D Accuitomo 170, Carestream 9300, Scanora 3D, I-CAT Next generation), one micro-CT scanner (SkyScan 1174) and one MSCT machine (Somatom Definition Flash) using two protocols (standard and high-resolution). MSCT and CBCT images were automatically spatially aligned on the micro-CT scan of the corresponding sample. A volume of interest was manually delineated on the micro-CT image and overlaid on the other scanning devices. Alveolar bone structures were automatically extracted using the adaptive thresholding algorithm. Based on the resulting binary images, an automatic 3D morphometric quantification was performed in a CT-Analyser (Bruker, Kontich, Belgium). The reliability and measurement errors were calculated for each modality compared to the gold standard micro-CT. Both MSCT and CBCT were associated with a clinically and statistically (P max, bone surface density -0.47 mm-1 min to 0.16 mm-1 max and trabecular thickness 0.15 mm min to 0.31 mm max) were significantly (P max and fractal dimension 0.08 min to 0.17 max) in all scanners compared to micro-CT. However, the structural pattern of the alveolar bone remained similar compared to that of the micro-CT for the ProMax 3D Max, NewTom GiANO, Cranex 3D, 3D Accuitomo 170 and Carestream 9300. On the other hand, the Scanora 3D, i-CAT Next Generation, standard and high-resolution MSCT displayed an overrated bone quantity and aberrant structural pattern compared to other scanning devices. The calculation of morphometric indices had an overall high reliability (intraclass correlation coefficient [ICC] 0.62 min to 0.99 max), except

Checking collagen preservation in archaeological bone by non-destructive studies (Micro-CT and IBA)

Science.gov (United States)

Beck, L.; Cuif, J.-P.; Pichon, L.; Vaubaillon, S.; Dambricourt Malassé, A.; Abel, R. L.

2012-02-01

The material to be studied is a piece of human skull discovered (1999) in Pleistocene sediments from the Orsang river (Gujarat state, India). From anatomical view point, this skull is highly composite: modern Homo sapiens characters are associated to undoubtedly more ancient features. Absolute dating by 14C is critical to understand this discovery. Prior to dating measurements, non-destructive studies have been carried out. Micro-CT reconstruction (X-ray microtomography) and Ion Beam Analysis (IBA) have been undertaken to check the structural preservation of the fossil and the collagen preservation. PIXE elemental map was used to select well-preserved bone area. RBS/EBS and NRA were used for light element quantification, in particular C, N and O contents. We also demonstrate that the PIXE-RBS/EBS combination is a effective tool for the whole characterization of archaeological and recent bones by analysing in one experiment both mineral and organic fractions. We have shown that the archaeological bone, a fragment of the potentially oldest modern Indian, is enough preserved for radiocarbon dating. We propose that Elastic Backscattering Spectrometry (EBS) using 3 MeV protons could be a good non destructive alternative to conventional CHN method using Carbon-Hydrogen-Nitrogen analyzer for measuring C and N before 14C dating.

Checking collagen preservation in archaeological bone by non-destructive studies (Micro-CT and IBA)

International Nuclear Information System (INIS)

Beck, L.; Cuif, J.-P.; Pichon, L.; Vaubaillon, S.; Dambricourt Malassé, A.; Abel, R.L.

2012-01-01

The material to be studied is a piece of human skull discovered (1999) in Pleistocene sediments from the Orsang river (Gujarat state, India). From anatomical view point, this skull is highly composite: modern Homo sapiens characters are associated to undoubtedly more ancient features. Absolute dating by 14 C is critical to understand this discovery. Prior to dating measurements, non-destructive studies have been carried out. Micro-CT reconstruction (X-ray microtomography) and Ion Beam Analysis (IBA) have been undertaken to check the structural preservation of the fossil and the collagen preservation. PIXE elemental map was used to select well-preserved bone area. RBS/EBS and NRA were used for light element quantification, in particular C, N and O contents. We also demonstrate that the PIXE-RBS/EBS combination is a effective tool for the whole characterization of archaeological and recent bones by analysing in one experiment both mineral and organic fractions. We have shown that the archaeological bone, a fragment of the potentially oldest modern Indian, is enough preserved for radiocarbon dating. We propose that Elastic Backscattering Spectrometry (EBS) using 3 MeV protons could be a good non destructive alternative to conventional CHN method using Carbon–Hydrogen–Nitrogen analyzer for measuring C and N before 14 C dating.

Checking collagen preservation in archaeological bone by non-destructive studies (Micro-CT and IBA)

Energy Technology Data Exchange (ETDEWEB)

Beck, L., E-mail: lucile.beck@cea.fr [C2RMF - UMR171 CNRS, Centre de Recherche et de Restauration des Musees de France, Palais du Louvre, Porte des Lions, 14 quai Francois Mitterrand, 75001 Paris (France); CEA, DEN, Service de Recherches de Metallurgie Physique, Laboratoire JANNUS, 91191 Gif-sur-Yvette (France); Cuif, J.-P. [UMR IDES 8148, Universite Paris XI-Orsay, 91405 Orsay cedex (France); Pichon, L. [C2RMF - UMR171 CNRS, Centre de Recherche et de Restauration des Musees de France, Palais du Louvre, Porte des Lions, 14 quai Francois Mitterrand, 75001 Paris (France); Vaubaillon, S. [CEA, INSTN, Laboratoire JANNUS, 91191 Gif-sur-Yvette (France); Dambricourt Malasse, A. [Departement de Prehistoire, Museum national d' Histoire naturelle, UMR 7194 - CNRS, Institut de Paleontologie Humaine, 1, rue Rene Panhard, 75013 Paris (France); Abel, R.L. [The Natural History Museum, London (United Kingdom)

2012-02-15

The material to be studied is a piece of human skull discovered (1999) in Pleistocene sediments from the Orsang river (Gujarat state, India). From anatomical view point, this skull is highly composite: modern Homo sapiens characters are associated to undoubtedly more ancient features. Absolute dating by {sup 14}C is critical to understand this discovery. Prior to dating measurements, non-destructive studies have been carried out. Micro-CT reconstruction (X-ray microtomography) and Ion Beam Analysis (IBA) have been undertaken to check the structural preservation of the fossil and the collagen preservation. PIXE elemental map was used to select well-preserved bone area. RBS/EBS and NRA were used for light element quantification, in particular C, N and O contents. We also demonstrate that the PIXE-RBS/EBS combination is a effective tool for the whole characterization of archaeological and recent bones by analysing in one experiment both mineral and organic fractions. We have shown that the archaeological bone, a fragment of the potentially oldest modern Indian, is enough preserved for radiocarbon dating. We propose that Elastic Backscattering Spectrometry (EBS) using 3 MeV protons could be a good non destructive alternative to conventional CHN method using Carbon-Hydrogen-Nitrogen analyzer for measuring C and N before {sup 14}C dating.

Subtraction and dynamic MR images of breast cancer

Energy Technology Data Exchange (ETDEWEB)

Murakami, Yoshitaka; Aoki, Manabu; Harada, Junta (Jikei Univ., Tokyo (Japan). School of Medicine)

1993-04-01

The purpose of this study was to evaluate the diagnostic effectiveness of subtraction and dynamic MR imaging in patients with breast masses. In 23 breast cancers and six fibroadenomas, spin echo T1 images were obtained at 0.2 Tesla before and every minute after intravenous injection of Gd-DTPA (0.1 or 0.2 mmol/kg). Subtraction images were obtained sequentially on the CRT monitor. All breast masses were enhanced after gadolinium and stood out as bright lesions on subtraction images. The tumor margin and its extension were more precisely evaluated on subtraction MR images than on conventional postcontrast MR images. Breast cancer showed a characteristic time-intensity curve with an early peak, in contrast to fibroadenoma, which showed a gradual increase in signal intensity. Subtraction MR imaging is a simple method for the evaluation of breast masses, and further, the time-intensity curve obtained by dynamic study is helpful in the differential diagnosis of lesions. (author).

SU-E-I-39: Combining Conventional Tomographic Imaging Strategy and Interior Tomography for Low Dose Dual-Energy CT (DECT)

Energy Technology Data Exchange (ETDEWEB)

Xu, Q [School of Electronic and Information Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China); Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Xing, L [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Xiong, G; Elmore, K; Min, J [Dalio Institute of Cardiovascular Imaging, New York- Presbyterian Hospital and Weill Cornell Medical College, New York, NY (United States)

2015-06-15

Purpose: Dual-energy CT (DECT) affords quantitative information of tissue density and provides a new dimension for disease diagnosis and treatment planning. The technique, however, increases the imaging dose because of the doubled scans, and thus hinders its widespread clinical applications. The purpose of this work is to develop a novel hybrid DECT image acquisition and reconstruction strategy, in which one of the energies is dealt by interior tomography while the other one is obtained using conventional tomography approach. Methods: In the proposed hybrid imaging strategy, the projection data of one of the energies (e.g., high-energy) were acquired and processed in an interior scanning model, whereas the other energy in the conventional tomographic approach. It known that, if the ROI is piecewise constant or polynomial, the interior ROI can be reconstructed with TV or HOT minimization. Here we extend the TV based interior reconstruction method into dual-energy situation. The ROI images so obtained were overlaid in the context of conventional CT of the companion energy. A material based composition in ROI was used in the proposed reconstruction framework. Results: In the simulation experiment with a diagnostic DECT geometry and energies, we were able to derive the densities of soft-tissues and bones in the ROI with high fidelity. In the experimental CBCT study, both kV and MV data were collected using the on-board kV and MV imaging system. The MV data were truncated only across the ROI. Using the interior tomography reconstruction above, we were able to obtain the ROI images as that obtained using un-truncated MV data with known tissue densities. Conclusion: The proposed DECT imaging strategy provides an effective way to extract tissue density information in the ROI and in the context of anatomical images of CT imaging, with much reduced imaging dose.

A simple digital subtraction angiographic instrument

International Nuclear Information System (INIS)

Ando, Hiroshi; Kobayashi, Tsuyoshi; Imai, Yutaka; Yanagishita, Akira

1983-01-01

A digital subtraction angiographic instrument was manufactured using a conventional x-ray TV for gastrointestinal series and a computer for processing of nuclear medical data. The results of visualization of the aorta and its primary branches were reviewed with demonstrable cases. (Chiba, N.)

Evaluation of Prostate Cancer Bone Metastases with 18F-NaF and 18F-Fluorocholine PET/CT.

Science.gov (United States)

Beheshti, Mohsen; Rezaee, Alireza; Geinitz, Hans; Loidl, Wolfgang; Pirich, Christian; Langsteger, Werner

2016-10-01

18 F-fluorocholine is a specific promising agent for imaging tumor cell proliferation, particularly in prostate cancer, using PET/CT. It is a beneficial tool in the early detection of marrow-based metastases because it excludes distant metastases and evaluates the response to hormone therapy. In addition, 18 F-fluorocholine has the potential to differentiate between degenerative and malignant osseous abnormalities because degenerative changes are not choline-avid; however, the agent may accumulate in recent traumatic bony lesions. On the other hand, 18 F-NaF PET/CT can indicate increased bone turnover and is generally used in the assessment of primary and secondary osseous malignancies, the evaluation of response to treatment, and the clarification of abnormalities on other imaging modalities or clinical data. 18 F-NaF PET/CT is a highly sensitive method in the evaluation of bone metastases from prostate cancer, but it has problematic specificity, mainly because of tracer accumulation in degenerative and inflammatory bone diseases. In summary, 18 F-NaF PET/CT is a highly sensitive method, but 18 F-fluorocholine PET/CT can detect early bone marrow metastases and provide greater specificity in the detection of bone metastases in patients with prostate cancer. However, the difference seems not to be significant. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Spontaneous vertebral dissection: Clinical, conventional angiographic, CT, and MR findings

Energy Technology Data Exchange (ETDEWEB)

Provenzale, J.M.; Morgenlander, J.C. [Duke Univ. Medical Center, Durham, NC (United States); Gress, D. [Univ. of California, San Francisco, CA (United States)

1996-03-01

The purpose of this study was to determine if typical clinical and neuroradiologic patterns exist in patients with spontaneous vertebral artery (VA) dissection. The medical records and neuroradiologic examinations of 14 patients with spontaneous VA dissection were reviewed. The medical records were examined to exclude patients with a history of trauma and to record evidence of a nontratimatic precipitating event ({open_quotes}trivial trauma{close_quotes}) and presence of possible risk factors such as hypertension. All patients under-went conventional angiography, 13 either CT or MRI (II both CT and MRI), and 3 MRA. Conventional arteriograrris were evaluated for dissection site, evidence of fibromuscular dysplasia, luminal stenosis or occlusion, and pseudoaneurysm formation, CT examinations for the presence of infarction or subarachnoid hemorrhage, MR examinations for the presence of infarction or arterial signal abnormality, and MR angiograms for abnormality of the arterial signal column. Seven patients had precipitating events within 24 h of onset of symptoms that may have been causative of dissection and five had hypertension. At catheter angiography, two patients had dissections in two arteries (both VAs in one patient, VA and internal carotid artery in one patient), giving a total of 15 VAs with dissection. Dissection sites included V1 in four patients, V2 in one patient, V3 in three patients, V4 in six patients, and both V3 and V4 in one patient. Luminal stenosis was present in 13 VAs, occlusion in 2, pseudoaneurysm in 1, and evidence of fibromuscular dysplasia in 1. Posterior circulation infarcts were found on CT or MR in five patients. Subarachnoid hemorrhage was found on CT in two patients and by lumbar puncture alone in two patients. Abnormal periarterial signal on MRI was seen in three patients. MRA demonstrated absent VA signal in one patient, pseudoaneurysm in one, and a false-negative examination in one.

Tumor Localization Using Cone-Beam CT Reduces Setup Margins in Conventionally Fractionated Radiotherapy for Lung Tumors

International Nuclear Information System (INIS)

Yeung, Anamaria R.; Li, Jonathan G.; Shi Wenyin; Newlin, Heather E.; Chvetsov, Alexei; Liu, Chihray; Palta, Jatinder R.; Olivier, Kenneth

2009-01-01

Purpose: To determine whether setup margins can be reduced using cone-beam computed tomography (CBCT) to localize tumor in conventionally fractionated radiotherapy for lung tumors. Methods and Materials: A total of 22 lung cancer patients were treated with curative intent with conventionally fractionated radiotherapy using daily image guidance with CBCT. Of these, 13 lung cancer patients had sufficient CBCT scans for analysis (389 CBCT scans). The patients underwent treatment simulation in the BodyFix immobilization system using four-dimensional CT to account for respiratory motion. Daily alignment was first done according to skin tattoos, followed by CBCT. All 389 CBCT scans were retrospectively registered to the planning CT scans using automated soft-tissue and bony registration; the resulting couch shifts in three dimensions were recorded. Results: The daily alignment to skin tattoos with no image guidance resulted in systematic (Σ) and random (σ) errors of 3.2-5.6 mm and 2.0-3.5 mm, respectively. The margin required to account for the setup error introduced by aligning to skin tattoos with no image guidance was approximately 1-1.6 cm. The difference in the couch shifts obtained from the bone and soft-tissue registration resulted in systematic (Σ) and random (σ) errors of 1.5-4.1 mm and 1.8-5.3 mm, respectively. The margin required to account for the setup error introduced using bony anatomy as a surrogate for the target, instead of localizing the target itself, was 0.5-1.4 cm. Conclusion: Using daily CBCT soft-tissue registration to localize the tumor in conventionally fractionated radiotherapy reduced the required setup margin by up to approximately 1.5 cm compared with both no image guidance and image guidance using bony anatomy as a surrogate for the target.

Physical principles of cardiac digital subtraction angiography

International Nuclear Information System (INIS)

Buonocore, E.; Pavlicek, W.

1986-01-01

Advances in the applications of computers with standard radiologic equipment have resulted in the development of electronic, or so-called ''film-less'' imaging. This technique, discussed by the authors, has become of particular value in the visualization of the central vascular system and has become known as digital subtraction angiography (DSA). Commercial products have become increasingly available and are capable of converting T.V. signals, obtained by conventional fluorography, to a computed array of digital values. Addition, subtraction, and averaging of this data, result in images with adequate signal-to-noise ratios that achieve detection of low concentrations of contrast media not possible with conventional screen film techniques. Computer subtraction of unnecessary background information improves the conspicuity of the opacified vessels to permit detection of vascular structures containing a concentration of no more than 1-3 percent of contrast media. This improved visualization is possible even with intravenous peripheral injections or reduced amounts of contrast media given intraarterially. With either method of contrast media administration, DSDA has become an excellent means of anatomic demonstration of the heart and great vessels with decreased morbidity and at lower cost

Imaging of primary pediatric lymphoma of bone

International Nuclear Information System (INIS)

Milks, Kathryn S.; McLean, Thomas W.; Anthony, Evelyn Y.

2016-01-01

Primary pediatric bone lymphoma is a rare form of non-Hodgkin lymphoma. Unlike nodal forms of lymphoma, imaging abnormalities in lymphoma of bone do not resolve rapidly in conjunction with treatment and radiologic findings can remain abnormal for years, making it difficult to evaluate treatment response. To evaluate the utility of imaging in assessment of patients with primary pediatric bone lymphoma. At our institution between 2004 and 2013, six cases of pathology-proven primary pediatric bone lymphoma were diagnosed. Retrospective chart review was performed to assess imaging utilization. Our data were qualitatively compared with existing literature to construct an algorithm for imaging patients with primary lymphoma of bone. Imaging evaluation of patients with primary pediatric bone lymphoma was highly variable at our institution. Conventional imaging was routinely used to evaluate response to treatment, despite lack of appreciable osseous change. Imaging in the absence of symptoms did not alter clinical management. Only positron emission tomography CT (PET/CT) proved capable of demonstrating imaging changes from the pretreatment to the post-treatment scans that were consistent with the clinical response to treatment. Surveillance imaging is likely unnecessary in patients with a known diagnosis of pediatric lymphoma of bone. Pretreatment and post-treatment PET/CT is likely sufficient to assess response. There is little data to support the use of interim and surveillance PET/CT. (orig.)

The contribution of chemical shift imaging with digital subtracting images to the diagnosis of steatohepatitis

International Nuclear Information System (INIS)

Guo Xinghua; Wang Juanping; Zhang Chongjie; Zheng Guofang; Fan Ruiqiang; Zhu Sumei; Liu Qiwang

2006-01-01

Objective: To investigate the diagnosis value of chemical shift imaging with digital subtracting in steatohepatitis. Methods: The in-phase images were subtracted by the out-phase ones in 34 cases of steatohepatitis, and the CNR were measured on these subtracted images to estimate the steatosis of the liver. The relationship of CT grade of steatohepatitis and CNR from the subtracted images was analyzed to evaluate the relationship between CNR and the degree of hepatic steatosis. The sensitivity and specificity of the subtracting and eyeballing methods were compared with chi-square test. Results: On the subtracted images, the liver and spleen were seen nearly the same aspects as low signals, CNR=0.98±0.06, meanwhile the spongy vertebra and the subcutaneous or abdominal lipid were seen as obvious higher signals in 52 normal cases. On the 34 steatohepatitis, scattered high signals were seen in the liver, which made the signal of liver higher than that of spleen, CNR=3.25±0.91--14.35±6.10. There was positive correlation between CNR and CT grade in the 34 cases of steatohepatitis, r=0.893, P<0.01. The sensitivity and specificity of the subtracting method were 88.24% and 94. 23%, significantly higher than that of the eyeballing results, 32.35% and 80.77%, P<0.01 and P<0.05. Conclusion: Chemical shift imaging with digital subtracting is a sensitive, specific, objective method to diagnose steatohepatitis and it is of potential ability for quantitative diagnosis. (authors)

Clinical application of CT-guided radiofrequency ablation for the treatment of metastatic bone neoplasms

International Nuclear Information System (INIS)

Gong Ju; Lu Zhijun; Wang Zhongmin; Zhang Liyun; Zheng Yunfeng; Chen Kemin

2009-01-01

Objective: To investigate the clinical efficacy of CT-guided radiofrequency ablation (RFA) for the treatment of metastatic bone neoplasms. Methods: Under intravenous aneaesthesia, CT- guided RFA was performed in 20 patients with metastatic bone tumor. The degree of pain was evaluated at 24 hours, 3 and 6 months after the operation by brief pain inventory (BPI). Results: All patients were followed up for 6 months and survived so far. The average peak pain score before the operation was 8.1 (6-10), which decreased significantly to 6.1, 4.6, 3.3 and 3.0 at 24 hours, 1, 3 and 6 months after the operation respectively (P<0.001). The mean pain score before the operation was 6.3, which decreased significantly to 4.0, 2.3, 2.13 and 1.9 at 24 hours, 1, 3 and 6 months after the operation respectively (P<0.001). After RFA treatment, the KPS scores of all patients increased while the CT values of the bone lesions decreased. No major complications occurred both during and after the operation. One patient with vertebral lamina destruction suffered from lower limb hypoesthesia after RFA procedure, and the lower limb sensation was restored within 48 hours after the injection of prednisone was employed. Conclusion: CT-guided radiofisequency ablation is a safe, effective, minimally-invasive and up-to-date technique for the treatment of metastatic bone neoplasms with excellent anti-pain effect, its short-term response is sure and reliable. (authors)

Micro-CT evaluation and histological analysis of screw-bone interface of expansive pedicle screw in osteoporotic sheep.

Science.gov (United States)

Wan, Shi-yong; Lei, Wei; Wu, Zi-xiang; Lv, Rong; Wang, Jun; Fu, Suo-chao; Li, Bo; Zhan, Ce

2008-04-01

To investigate the properties of screw-bone interface of expansive pedicle screw (EPS) in osteoporotic sheep by micro-CT and histological observation. Six female sheep with bilateral ovariectomy-induced osteoporosis were employed in this experiment. After EPS insertion in each femoral condyle, the sheep were randomly divided into two groups: 3 sheep were bred for 3 months (Group A), while the other 3 were bred for 6 months (Group B). After the animals being killed, the femoral condyles with EPS were obtained, which were three-dimensionally-imaged and reconstructed by micro-CT. Histological evaluation was made thereafter. The trabecular microstructure was denser at the screw-bone interface than in the distant parts in expansive section, especially within the spiral marking. In the non-expansive section, however, there was no significant difference between the interface and the distant parts. The regions of interest (ROI) adjacent to EPS were reconstructed and analyzed by micro-CT with the same thresholds. The three-dimensional (3-D) parameters, including tissue mineral density (TMD), bone volume fraction (BVF, BV/TV), bone surface/bone volume (BS/BV) ratio, trabecular thickness (Tb.Th), and trabecular separation (Tb.Sp), were significantly better in expansive sections than non-expansive sections (P less than 0.05). Histologically, newly-formed bony trabeculae crawled along the expansive fissures and into the center of EPS. The newly-formed bones, as well as the bones at the bone-screw interface, closely contacted with the EPS and constructed four compartments. The findings of the current study, based on micro-CT and histological evaluation, suggest that EPS can significantly provide stabilization in osteoporotic cancellous bones.

Dynamic contrast-enhanced subtraction MR angiography in intracranial vascular abnormalities

International Nuclear Information System (INIS)

Takano, K.; Ono, H.; Utsunomiya, H.; Okazaki, M.; Tanaka, A.

1999-01-01

We present our clinical experience with dynamic contrast-enhanced MR angiography (MRA) with subtraction for assessing intracranial vascular abnormalities. Ten patients with various cerebrovascular disorders underwent dynamic contrast-enhanced MRA on a 1.0-T system. Thirty sections (2 mm) were acquired in 29-30 s. Maximum intensity projection images and subtracted source images were compared with those obtained by conventional angiography. In all cases, the presence or absence of abnormalities in the targeted vessels, as well as the morphology of the sagittal sinuses, was clearly visualized as in conventional angiography, without any obstructions such as hyperintense hematomas or thrombi, or intraluminal turbulence. Although the temporal and spatial resolutions with current hardware are insufficient, these preliminary results suggest that dynamic contrast-enhanced MRA with subtraction may be useful for assessing vascular lesions with hemorrhage or thrombus, and the dural sinuses. (orig.)

The demonstration of the auditory ossicles by high resolution CT

International Nuclear Information System (INIS)

Lloyd, G.A.S.; Boulay, G.H. du; Phelps, P.D.; Pullicino, P.

1979-01-01

The high resolution CT scanning system introduced by EMI in 1978 has added a new dimension to computerised tomography in otology. The apparatus used for this study was an EMI CT 5005 body scanner adapted for head and neck scanning and incorporating a high resolution facility. The latter has proved most advantageous in areas of relatively high differential absorption, so that its application to the demonstration of abnormalities in the petrous temporal bone, and in particular middle ear disease, has been very rewarding. Traumatic ossicular disruptions may now be demonstrated and the high contrast of CT often shows them better than conventional hypocycloidal tomography. The stapes is also better visualised and congenital abnormalities of its superstructure have been recorded. These studies have been achieved with a very acceptable level of radiation to the eye, lens and cornea and the technique is clearly a rival to conventional pluridirectional tomography in the assessment of the petrous temporal bone. With further design improvements high resolution CT could completely replace existing techniques. (orig.) [de

3D-CT of the temporal bone area with high-speed processing

International Nuclear Information System (INIS)

Hattori, Taku

1994-01-01

Three-dimentional (3D)-CT was introduced to represent abnormal findings in the temporal bone area utilizing a SOMATOM DRH CT scanner with accessory 3D reconstruction software and an exclusive high-speed 3D processing system, VOXEL FLINGER. In a patient with eosinophilic granuloma, a defect in the squamous part of the temporal bone was demonstrated suggesting exposure of the dura mater during surgery. In a patient with a normal ear, well-developed mastoid cavity, a part of the handle and the head of the malleus, the incudomalleal joint, the short limb, body and a part of the long limb of the incus and the round window niche were demonstrated. In a case of chronic otitis media, poorly developed mastoid cavity and a possible defect of the tip of the long limb of the incus were demonstrated, in contrast to the patient with the normal ear. 3D-CT yields objective and solid images which are useful for diagnosis, treatment planning and explanation of the pathology to patients and their family. To obtain convincing 3D images, physicians themselves have to choose exact rotation angles. It is not adequate to reconstruct original CT data using a CT computer with accessory 3D software whose processing capability is not good enough for this purpose. The conclusion is as follows: 1) it is necessary and effective to transfer original CT data into the memory of the exclusive high-speed 3D processing system and 2) process the data by the voxel memory method to establish a clinically valuable 3D-CT imaging system. (author)

Normal bone and soft tissue distribution of fluorine-18-sodium fluoride and artifacts on 18F-NaF PET/CT bone scan: a pictorial review.

Science.gov (United States)

Sarikaya, Ismet; Elgazzar, Abdelhamid H; Sarikaya, Ali; Alfeeli, Mahmoud

2017-10-01

Fluorine-18-sodium fluoride (F-NaF) PET/CT is a relatively new and high-resolution bone imaging modality. Since the use of F-NaF PET/CT has been increasing, it is important to accurately assess the images and be aware of normal distribution and major artifacts. In this pictorial review article, we will describe the normal uptake patterns of F-NaF in the bone tissues, particularly in complex structures, as well as its physiologic soft tissue distribution and certain artifacts seen on F-NaF PET/CT images.

Longitudinal in vivo evaluation of bone regeneration by combined measurement of multi-pinhole SPECT and micro-CT for tissue engineering

Science.gov (United States)

Lienemann, Philipp S.; Metzger, Stéphanie; Kiveliö, Anna-Sofia; Blanc, Alain; Papageorgiou, Panagiota; Astolfo, Alberto; Pinzer, Bernd R.; Cinelli, Paolo; Weber, Franz E.; Schibli, Roger; Béhé, Martin; Ehrbar, Martin

2015-05-01

Over the last decades, great strides were made in the development of novel implants for the treatment of bone defects. The increasing versatility and complexity of these implant designs request for concurrent advances in means to assess in vivo the course of induced bone formation in preclinical models. Since its discovery, micro-computed tomography (micro-CT) has excelled as powerful high-resolution technique for non-invasive assessment of newly formed bone tissue. However, micro-CT fails to provide spatiotemporal information on biological processes ongoing during bone regeneration. Conversely, due to the versatile applicability and cost-effectiveness, single photon emission computed tomography (SPECT) would be an ideal technique for assessing such biological processes with high sensitivity and for nuclear imaging comparably high resolution (designed poly(ethylene glycol)-based hydrogels that release bone morphogenetic protein to guide the healing of critical sized calvarial bone defects. By combined in vivo longitudinal multi-pinhole SPECT and micro-CT evaluations we determine the spatiotemporal course of bone formation and remodeling within this synthetic hydrogel implant. End point evaluations by high resolution micro-CT and histological evaluation confirm the value of this approach to follow and optimize bone-inducing biomaterials.

The advantage of the three dimensional computed tomographic (3 D-CT for ensuring accurate bone incision in sagittal split ramus osteotomy

Directory of Open Access Journals (Sweden)

Coen Pramono D

2005-03-01

Full Text Available Functional and aesthetic dysgnathia surgery requires accurate pre-surgical planning, including the surgical technique to be used related with the difference of anatomical structures amongst individuals. Programs that simulate the surgery become increasingly important. This can be mediated by using a surgical model, conventional x-rays as panoramic, cephalometric projections and another sophisticated method such as a three dimensional computed tomography (3 D-CT. A patient who had undergone double jaw surgeries with difficult anatomical landmarks was presented. In this case the mandible foramens were seen highly relatively related to the sigmoid notches. Therefore, ensuring the bone incisions in sagittal split was presumed to be difficult. A 3D-CT was made and considered to be very helpful in supporting the pre-operative diagnostic.

CT examination of the temporal bones for cochlear implantation; Badanie CT kosci skroniowych u osob przygotowanych do operacji wszczepu slimakowego

Energy Technology Data Exchange (ETDEWEB)

Szyfter, W.; Szymiec, E.; Pruszewicz, A.; Szmeja, Z.; Paprzycki, W.; Sekula, A.; Przybylska, J. [Klinika Otolaryngologii, Akademia Medyczna, Poznan (Poland)

1995-12-31

CT examinations of temporal bones were performed in 31 deaf patients from qualify diagnostic stage prepared for cochlear implants. Essential for surgical treatment anatomic details were estimated, especially canalis spiralis cochleae was paid to attention. In our group, 8 patients had some CT changes (abnormal findings) which corresponded to different stages of obliteration the cochlea. The majority of patients lost the hearing because of meningitis. In 6 implanted patients CT scan was compared with surgical findings. During the operation 1 patient with patent cochlea on CT scan had partially ossified basal turn. (author) 16 refs, 4 figs, 2 tabs

Quantification and visualization of alveolar bone resorption from 3D dental CT images

International Nuclear Information System (INIS)

Nagao, Jiro; Mori, Kensaku; Kitasaka, Takayuki; Suenaga, Yasuhito; Yamada, Shohzoh; Naitoh, Munetaka

2007-01-01

Purpose A computer aided diagnosis (CAD) system for quantifying and visualizing alveolar bone resorption caused by periodontitis was developed based on three-dimensional (3D) image processing of dental CT images. Methods The proposed system enables visualization and quantification of resorption of alveolar bone surrounding and between the roots of teeth. It has the following functions: (1) vertical measurement of the depth of resorption surrounding the tooth in 3D images, avoiding physical obstruction; (2) quantification of the amount of resorption in the furcation area; and (3) visualization of quantification results by pseudo-color maps, graphs, and motion pictures. The resorption measurement accuracy in the area surrounding teeth was evaluated by comparing with dentist's recognition on five real patient CT images, giving average absolute difference of 0.87 mm. An artificial image with mathematical truth was also used for measurement evaluation. Results The average absolute difference was 0.36 and 0.10 mm for surrounding and furcation areas, respectively. The system provides an intuitive presentation of the measurement results. Conclusion Computer aided diagnosis of 3D dental CT scans is feasible and the technique is a promising new tool for the quantitative evaluation of periodontal bone loss. (orig.)

99mTc MDP SPECT-CT-Based Modified Mirels Classification for Evaluation of Risk of Fracture in Skeletal Metastasis: A Pilot Study.

Science.gov (United States)

Riaz, Saima; Bashir, Humayun; Niazi, Imran Khalid; Butt, Sumera; Qamar, Faisal

2018-06-01

Mirels' scoring system quantifies the risk of sustaining a pathologic fracture in osseous metastases of weight bearing long bones. Conventional Mirels' scoring is based on radiographs. Our pilot study proposes Tc MDP bone SPECT-CT based modified Mirels' scoring system and its comparison with conventional Mirels' scoring. Cortical lysis was noted in 8(24%) by SPECT-CT versus 2 (6.3%) on X-rays. Additional SPECT-CT parameters were; circumferential involvement [1/4 (31%), 1/2 (3%), 3/4 (37.5%), 4/4 (28%)] and extra-osseous soft tissue [3%]. Our pilot study suggests the potential role of SPECT-CT in predicting risk of fracture in osseous metastases.

Evaluation of CT-scanning of the temporal bone in the diagnosis of ear diseases

International Nuclear Information System (INIS)

Murata, Kiyotaka; Isono, Michio; Nishimae, Tadahide; Tamaki, Katsuhiko; Hosoi, Hiroshi; Ohta, Fumihiko

1983-01-01

CT-scanning of 96 temporal bones was carried out to reveal the extension of cholesteatoma, periossicular drainage, fracture lines, enlarged internal acoustic meatus and anomalies of labyrinthine capsules and ossicles. The clinical aspects of CT-scanning of the temporal bone (CTTB) were as follows: 1) Inner ear anomalies were observed in 17 temporal bones of unilateral deafness, high tone loss from unknown origin and fluctuant hearing loss. CTTB may explain the pathology of deafness from unknown origin. 2) Inner ear anomalies may be classified into more detailed groups than before. 3) The extension of cholesteatoma, localization and size of labyrinthine fistula can be estimated prior to surgery. 4) Cholesteatoma in a mastoidectomy cavity may be detected. 5) The malleus and incus may be visualized, although the stapes can hardly be found. 6) Fracture lines of a temporal bone, destruction of the internal acoustic meatus may be clearly detected. (author)

Sexual difference of human hyoid bones. Quantitative analysis of CT three-dimensional image

International Nuclear Information System (INIS)

Terashima, Yoshiharu; Izumi, Masahiro; Hanamura, Hajime; Takada, Yasushi

2007-01-01

We investigated sexual differences in hyoid bones of 50 dissected Japanese cadavers: 26 males (aged 52 to 101, averaged 81.9 years) and 24 females (aged 61 to 94, averaged 83.6 years). All extracted hyoid bones were scanned by multi-slice CT. Length of body, distance between bilateral greater horns, length of greater horns, distance between bilateral lesser horns, and length of lesser horns were measured on CT three-dimensional image, and were analyzed by univariate and multivariate statistics. t-tests showed significant sexual differences in all the dimensions; being about 20% longer in males than in females. In principal component analysis using five hyoid dimensions, factor 1, expressing the overall size of the bone, fairly separated each sex, but factors 2 and 3, expressing the shape, did not. Discriminant analysis by a stepwise model, using all the eight dimensions, classified sex rightly (88.6% of the bone) by a function of two dimensions: length of body and distance between bilateral tips of lesser horns. In conclusion, a sexual difference of the hyoid bone was evident in size rather than in shape. (author)

A comparison of micro-CT, microradiography and histomorphometry in bone research

NARCIS (Netherlands)

Gielkens, Pepijn F. M.; Schortinghuis, Jurjen; de Jong, Johan R.; Huysmans, Marie Charlotte D. N. J. M.; van Leeuwen, M. Barbara M.; Raghoebar, Gerry M.; Bos, Ruud R. M.; Stegenga, Boudewijn

Objective: Intraobserver reliability and agreement were determined for microradiography (MR), micro-computed tomography (mu CT) and histomorphometry (HM). These three modalities were compared for quantitative measurements of bone formation and graft modelling in rat mandibular defects and grafts.

The value of whole-body bone scan combined with SPECT/CT in diagnosing benign and malignant vertebral fractures

International Nuclear Information System (INIS)

Xu Feng; Ma Yubo; Yuan Qi

2012-01-01

Objective: To evaluate the value of whole-body bone scan (WBS) combined with SPECT/CT in diagnosing of benign and malignant vertebral fractures. Methods: WBS and SPECT/CT data of 52 cases with vertebral fractures were reviewed and analyzed retrospectively, and the differences between the benign and malignant vertebral fractures were compared. Results: WBS found 78.8% (41/52) patients had lesions in the bones besides the spine, but the benign group was less in number. SPECT/CT found that malignant group was more likely to have bone destructions or pedicle radionuclide uptake than the benign group.Both of them had no radioactivity concentration in the tuberculosis or hyperparathyroidism. Conclusion: Although it still had some limitations,WBS combined with SPECT/CT is valuable in the diagnosis of benign and malignant vertebral fractures. (authors)

Indeterminate lesions on planar bone scintigraphy in lung cancer patients: SPECT, CT or SPECT-CT?

International Nuclear Information System (INIS)

Sharma, Punit; Kumar, Rakesh; Singh, Harmandeep; Bal, Chandrasekhar; Malhotra, Arun; Julka, Pramod Kumar; Thulkar, Sanjay

2012-01-01

The objective of the present study was to compare the role of single photon emission computed tomography (SPECT), computed tomography (CT) and SPECT-CT of selected volume in lung cancer patients with indeterminate lesions on planar bone scintigraphy (BS). The data of 50 lung cancer patients (53 ± 10.3 years; range 30-75; male/female 38/12) with 65 indeterminate lesions on planar BS (January 2010 to November 2010) were retrospectively evaluated. All of them underwent SPECT-CT of a selected volume. SPECT, CT and SPECT-CT images were independently evaluated by two experienced readers (experience in musculoskeletal imaging, including CT: 5 and 7 years) in separate sessions. A scoring scale of 1 to 5 was used, in which 1 is definitely metastatic, 2 is probably metastatic, 3 is indeterminate, 4 is probably benign and 5 is definitely benign. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for each modality, taking a score ≤2 as metastatic. With receiver operating characteristic (ROC) curve analysis, areas under the curve (AUC) were calculated for each modality and compared. Clinical and imaging follow-up and/or histopathology were taken as reference standard. For both readers SPECT was inferior to CT (P = 0.004, P = 0.022) and SPECT-CT (P = 0.003, P = 0.037). However, no significant difference was found between CT and SPECT-CT for reader 1 (P = 0.847) and reader 2 (P = 0.592). The findings were similar for lytic as well as sclerotic lesions. Moderate inter-observer agreement was seen for SPECT images (κ = 0.426), while almost perfect agreement was seen for CT (κ = 0.834) and SPECT-CT (κ = 0.971). CT alone and SPECT-CT are better than SPECT for accurate characterisation of indeterminate lesions on planar BS in lung cancer patients. CT alone is not inferior to SPECT-CT for this purpose and might be preferred because of shorter acquisition time and wider availability. (orig.)

μCT-based, in vivo dynamic bone histomorphometry allows 3D evaluation of the early responses of bone resorption and formation to PTH and alendronate combination therapy.

Science.gov (United States)

de Bakker, Chantal M J; Altman, Allison R; Tseng, Wei-Ju; Tribble, Mary Beth; Li, Connie; Chandra, Abhishek; Qin, Ling; Liu, X Sherry

2015-04-01

Current osteoporosis treatments improve bone mass by increasing net bone formation: anti-resorptive drugs such as bisphosphonates block osteoclast activity, while anabolic agents such as parathyroid hormone (PTH) increase bone remodeling, with a greater effect on formation. Although these drugs are widely used, their role in modulating formation and resorption is not fully understood, due in part to technical limitations in the ability to longitudinally assess bone remodeling. Importantly, it is not known whether or not PTH-induced bone formation is independent of resorption, resulting in controversy over the effectiveness of combination therapies that use both PTH and an anti-resorptive. In this study, we developed a μCT-based, in vivo dynamic bone histomorphometry technique for rat tibiae, and applied this method to longitudinally track changes in bone resorption and formation as a result of treatment with alendronate (ALN), PTH, or combination therapy of both PTH and ALN (PTH+ALN). Correlations between our μCT-based measures of bone formation and measures of bone formation based on calcein-labeled histology (r=0.72-0.83) confirm the accuracy of this method. Bone remodeling parameters measured through μCT-based in vivo dynamic bone histomorphometry indicate an increased rate of bone formation in rats treated with PTH and PTH+ALN, together with a decrease in bone resorption measures in rats treated with ALN and PTH+ALN. These results were further supported by traditional histology-based measurements, suggesting that PTH was able to induce bone formation while bone resorption was suppressed. Copyright © 2014 Elsevier Inc. All rights reserved.

3D-MR vs. 3D-CT of the shoulder in patients with glenohumeral instability

Energy Technology Data Exchange (ETDEWEB)

Stillwater, Laurence; Koenig, James; Maycher, Bruce; Davidson, Michael [University of Manitoba, Winnipeg (Canada)

2017-03-15

To determine whether 3D-MR osseous reformats of the shoulder are equivalent to 3D-CT osseous reformats in patients with glenohumeral instability. Patients with glenohumeral instability, who were to be imaged with both CT and MRI, were prospectively selected. CT and MR were performed within 24 h of one another on 12 shoulders. Each MR study included an axial 3D isotropic VIBE sequence. The image data from the isotropic VIBE sequence were post-processed using subtraction and 3D software. CT data were post-processed using 3D software. The following measurements were obtained for both 3D-CT and 3D-MR post-processed images: height and width of the humeral head and glenoid, Hill-Sachs size and percent humeral head loss (if present), size of glenoid bone loss and percent glenoid bone loss (if present). Paired t-tests and two one-sided tests for equivalence were used to assess the differences between imaging modalities and equivalence. The measurement differences from the 3D-CT and 3D-MR post-processed images were not statistically significant. The measurement differences for humeral height, glenoid height and glenoid width were borderline statistically significant; however, using any adjustment for multiple comparisons, this failed to be significant. Using an equivalence margin of 1 mm for measurements and 1.5% for percent bone loss, the 3D-MR and 3D-CT post-processed images were equivalent. Three-dimensional-MR osseous models of the shoulder using a 3D isotropic VIBE sequence were equivalent to 3D-CT osseous models, and the differences between modalities were not statistically significant. (orig.)

CT in dental osseointegration

International Nuclear Information System (INIS)

Witte, D.

1992-01-01

Computerised tomography (CT) plays a key role in the pre-surgical evaluation of the alveolar process for titanium dental implants. The successful replacement of lost teeth by tissue integrated tooth root implants is a major advance in clinical dentistry. The paper will discuss briefly the history of osseointegration and how CT is now involved in helping the edentulous patient. CT is considered as a quick and convenient method of obtaining excellent anatomical information about the maxilla. Conventional tomography is difficult to obtain and does not provide valuable cross-sectional images. Exact height and width calculations can be made as well as screening out patients with advanced bone resorption. 3 refs. 6 figs

A meta-analysis of 18FDG-PET–CT, 18FDG-PET, MRI and bone scintigraphy for diagnosis of bone metastases in patients with lung cancer

International Nuclear Information System (INIS)

Qu Xinhua; Huang Xiaolu; Yan Weili; Wu Lianming; Dai Kerong

2012-01-01

Background and purpose: Lung cancer is the most common cause of cancer related death among both men and women worldwide. The skeleton is the most common site of cancer metastasis. Early detection is crucial for prognosis. To evaluate and compare the capability for bone metastasis assessment of [ 18 F] fluoro-2-D-glucose positron emission tomography with computed tomography ( 18 FDG-PET–CT), [ 18 F] fluoro-2-D-glucose positron emission tomography ( 18 FDG-PET), magnetic resonance imaging (MRI) and bone scintigraphy (BS) in lung cancer patients, a meta-analysis is preformed. Methods: We searched MEDLINE, OVID, EMBASE and the Cochrane Library for studies evaluating diagnosis validity of 18 FDG-PET–CT, 18 FDG-PET, MRI and BS between January 1990 and August 2010. Meta-analysis methods were used to pool sensitivity, specificity, diagnostic odd ratios (DORs) and to construct a summary receiver-operating characteristic curve (SROC). Results: A total of 17 articles (9 18 FDG-PET–CT studies, 9 18 FDG-PET studies, 6 MRI studies and 16 BS studies) that included 2940 patients who fulfilled all of the inclusion criteria were considered for inclusion in the analysis. The pooled sensitivity for the detection of bone metastasis in lung cancer using 18 FDG-PET–CT, 18 FDG-PET, MRI and BS were 0.92 (95% CI, 0.88–0.95), 0.87 (95% CI, 0.81–0.92), 0.77 (95% CI, 0.65–0.87) and 0.86 (95% CI, 0.82–0.89), respectively. The pooled specificity for the detection of bone metastasis from lung cancer using 18 FDG-PET–CT, 18 FDG-PET, MRI and BS were 0.98 (95% CI, 0.97–0.98), 0.94 (95% CI, 0.92–0.96), 0.92 (95% CI, 0.88–0.95), 0.88 (95% CI, 0.86–0.89), respectively. The pooled DORs estimates for 18 FDG-PET–CT 449.17 were significantly higher than for 18 FDG-PET (118.25, P 18 FDG-PET–CT and 18 FDG-PET were better imaging methods for diagnosing bone metastasis from lung cancer than MRI and BS. 18 FDG-PET–CT has higher diagnostic value (sensitivity, specificity and DORs

Diagnostic imaging in polytrauma: comparison of radiation exposure from whole-body MSCT and conventional radiography with organ-specific CT

International Nuclear Information System (INIS)

Wedegaertner, U.; Lorenzen, M.; Weber, C.; Adam, G.; Nagel, H.D.

2004-01-01

Purpose: To compare the radiation dose of whole-body multislice CT (MSCT) and conventional radiography with organ-specific CT in polytrauma. Materials and Methods: The whole-body MSCT encompassing brain, neck and midface, chest, abdomen and pelvis was performed on a Somatom Volume Zoom (Siemens). Conventional radiography consisted of chest and cervical, thoracic and lumbar spine in two views as well as pelvis. Polymat, Siemens. Three combinations of organ specific CT were chosen: CT examination of (1) head and cervical spine, (2) head, cervical spine and chest, (3) head, cervical spine and abdomen. The effective doses of whole-body MSCT and conventional radiography with organ-specific CT were calculated. Results: Effective doses were 20 mSv for whole-body MSCT, 2 mSv for conventional x-ray, and 5 mSv for combination (1), 8 mSv for combination (2) and (3) 16 mSv for combination (3) of the organ-specific CT. The ratio of radiation dose between whole-body MSCT and radiography was 10: 1. This ratio was reduced to 3: 1, 2: 1 and 1: 1 when a combination of radiography and CT was performed. Conclusions: Whole-body MSCT in polytrauma compared to conventional radiography with organ-specific CT induces a threefold increased dose in unfavorable situations and no increased dose in favorable situations. Nevertheless, routine use of whole-body MSCT should be critically evaluated and should be adapted to the clinical benefit. (orig.) [de

Usefulness of bone window CT images parallel to the transnasal surgical route for pituitary disorders

International Nuclear Information System (INIS)

Abe, T.; Kunii, N.; Ikeda, H.; Izumiyama, H.; Asahina, N.

2003-01-01

Before operating on 130 patients with pituitary disorders, we evaluated their bone window CT images sliced parallel to the trans nasal surgical route to assess the surgical anatomy of the nasal cavity for trans nasal surgery. High resolution bone window CT was performed in 3- to 5-mm slices parallel to the imaginary line connecting the inferior margin of the piriform aperture and the top of the sellar floor, parallel to the trans nasal surgical route. This CT angle was useful in evaluating the width and depth of the operative hold, the bony components of the nasal conchas, deviation of the nasal septum, the bony structure and mucosa in the sphenoid sinus, and the condition of the sellar floor. In patients requiring repeat surgery, the location of thin or thick nasal mucosa, residual bony septum, and inadequate sellar floor opening were easily detected. Bone window CT images sliced parallel to the trans nasal surgical route provide direct visualization of the nasal anatomy for the trans nasal approach. This method is helpful in determining how far to remove the sellar floor laterally, especially in cases requiring repeat surgery. (author)

Intra-arterial digital subtraction angiography in the diagnosis of insulinomas

International Nuclear Information System (INIS)

Moulopoulou, A.; Vlahos, L.

1988-01-01

Two cases of surgically proved benign insulinoma of the pancreas were correctly localized with intra-arterial digital subtraction angiography (IA-DSA) of the coeliac and the superior mesenteric artery, while the respective dynamic computed tomography (CT) and ultrasound (US) examinations were negative. In a third case of organic hyperinsulinism, IA-DSA, CT and US suggested a pancreatic islet-cell tumor, but the histological examination of the resected suspicious area was that of focal hyperplasia. 17 refs.; 3 figs

Bone Healing Around Dental Implants: Simplified vs Conventional Drilling Protocols at Speed of 400 rpm.

Science.gov (United States)

Gil, Luiz Fernando; Sarendranath, Alvin; Neiva, Rodrigo; Marão, Heloisa F; Tovar, Nick; Bonfante, Estevam A; Janal, Malvin N; Castellano, Arthur; Coelho, Paulo G

This study evaluated whether simplified drilling protocols would provide comparable histologic and histomorphometric results to conventional drilling protocols at a low rotational speed. A total of 48 alumina-blasted and acid-etched Ti-6Al-4V implants with two diameters (3.75 and 4.2 mm, n = 24 per group) were bilaterally placed in the tibiae of 12 dogs, under a low-speed protocol (400 rpm). Within the same diameter group, half of the implants were inserted after a simplified drilling procedure (pilot drill + final diameter drill), and the other half were placed using the conventional drilling procedure. After 3 and 5 weeks, the animals were euthanized, and the retrieved bone-implant samples were subjected to nondecalcified histologic sectioning. Histomorphology, bone-to-implant contact (BIC), and bone area fraction occupancy (BAFO) analysis were performed. Histology showed that new bone was formed around implants, and inflammation or bone resorption was not evident for both groups. Histomorphometrically, when all independent variables were collapsed over drilling technique, no differences were detected for BIC and BAFO; when drilling technique was analyzed as a function of time, the conventional groups reached statistically higher BIC and BAFO at 3 weeks, but comparable values between techniques were observed at 5 weeks; 4.2-mm implants obtained statistically higher BAFO relative to 3.75-mm implants. Based on the present methodology, the conventional technique improved bone formation at 3 weeks, and narrower implants were associated with less bone formation.

Intravenous contrast injection significantly affects bone mineral density measured on CT

NARCIS (Netherlands)

Pompe, Esther; Willemink, Martin J.; Dijkhuis, Gawein R.; Verhaar, Harald J. J.; Mohamed Hoesein, Firdaus A A; de Jong, Pim A.

OBJECTIVE: The objective is to evaluate the effect of intravenous contrast media on bone mineral density (BMD) assessment by comparing unenhanced and contrast-enhanced computed tomography (CT) examinations performed for other indications. METHODS: One hundred and fifty-two patients (99 without and

The role of spiral CT in pelvic trauma management

International Nuclear Information System (INIS)

Cheung, E.C.F.; Fung, K.K.L.

1999-01-01

Rapid and accurate assessment of pelvic injury is critical for good patient management. Plain X-ray is often used as a preliminary evaluation of the injury but this may not give adequate diagnosis of the acetabulum fracture, subtle fracture of the pelvic bone and the associated soft tissue injuries. Nowadays, spiral CT has taken an increasing role in the evaluation of pelvic trauma. It gives a rapid assessment of the bone and soft tissue injuries as compared to conventional CT. Besides, 2-D (multiplanar imaging) and 3-D image reconstruction with multiple angle views, provide the maximum information which facilitates detailed pelvic trauma evaluation. Three cases were used to illustrate the role of spiral CT in pelvic trauma management. Copyright (1999) Blackwell Science Pty Ltd

Evaluation of the diagnostic performance of SPECT coupled to tomodensitometry (SPECT-CT) in the daily practice of bone scintigraphy at the Nuclear Medical station of Nancy

International Nuclear Information System (INIS)

Netter, F.; Journo, A.; Mayer, J.C.; Grandpierre, S.; Daragon, N.; Karcher, G.; Olivier, P.; Scigliano, S.

2008-01-01

Objective: The purpose of our study was to evaluate the diagnostic performance of SPECT coupled to computed axial tomography (SPECT- CT) in our daily practice of bone scintigraphy. Subjects and methods: SPECT- CT obtained as a complement to the planar bone scintigraphy in 39 patients were studied. Each type of image was retrospectively read by two different observers: a nuclear medicine physician who was unaware of SPECT- CT results analysed planar bone scintigraphy, a second one who was unaware of planar bone scintigraphy results analysed SPECT- CT images. In this population of patients, 17 patients were addressed in an oncologic setting. The 22 other patients were addressed for pain of indeterminate origin without neoplastic context. Results: In 13% of the cases, SPECT- CT specified the precise location of increased uptake foci seen on planar bone scintigraphy. In 38% of cases, SPECT- CT confirmed a diagnosis suspected by the planar bone scintigraphy. In 10% of cases, SPECT- CT established a diagnosis that was uncertain with planar bone scintigraphy. In 26% of cases, SPECT- CT brought no additional information. Finally in 3% of cases, SPECT- CT proved to be more sensitive than planar images. Conclusion: Our study demonstrates the utility of SPECT- CT in the daily practice of bone scintigraphy, this complementary imaging study benefited to 74% of our patients. (authors)

Quantitative assessment of bone defect healing by multidetector CT in a pig model

International Nuclear Information System (INIS)

Riegger, Carolin; Kroepil, Patric; Lanzman, Rotem S.; Miese, Falk R.; Antoch, Gerald; Scherer, Axel; Jungbluth, Pascal; Hakimi, Mohssen; Wild, Michael; Hakimi, Ahmad R.

2012-01-01

To evaluate multidetector CT volumetry in the assessment of bone defect healing in comparison to histopathological findings in an animal model. In 16 mini-pigs, a circumscribed tibial bone defect was created. Multidetector CT (MDCT) of the tibia was performed on a 64-row scanner 42 days after the operation. The extent of bone healing was estimated quantitatively by MDCT volumetry using a commercially available software programme (syngo Volume, Siemens, Germany).The volume of the entire defect (including all pixels from -100 to 3,000 HU), the nonconsolidated areas (-100 to 500 HU), and areas of osseous consolidation (500 to 3,000 HU) were assessed and the extent of consolidation was calculated. Histomorphometry served as the reference standard. The extent of osseous consolidation in MDCT volumetry ranged from 19 to 92% (mean 65.4 ± 18.5%). There was a significant correlation between histologically visible newly formed bone and the extent of osseous consolidation on MDCT volumetry (r = 0.82, P < 0.0001). A significant negative correlation was detected between osseous consolidation on MDCT and histological areas of persisting defect (r = -0.9, P < 0.0001). MDCT volumetry is a promising tool for noninvasive monitoring of bone healing, showing excellent correlation with histomorphometry. (orig.)

Quantitative assessment of bone defect healing by multidetector CT in a pig model

Energy Technology Data Exchange (ETDEWEB)

Riegger, Carolin; Kroepil, Patric; Lanzman, Rotem S.; Miese, Falk R.; Antoch, Gerald; Scherer, Axel [University Duesseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Duesseldorf (Germany); Jungbluth, Pascal; Hakimi, Mohssen; Wild, Michael [University Duesseldorf, Medical Faculty, Department of Traumatology and Hand Surgery, Duesseldorf (Germany); Hakimi, Ahmad R. [Universtity Duesseldorf, Medical Faculty, Department of Oral Surgery, Duesseldorf (Germany)

2012-05-15

To evaluate multidetector CT volumetry in the assessment of bone defect healing in comparison to histopathological findings in an animal model. In 16 mini-pigs, a circumscribed tibial bone defect was created. Multidetector CT (MDCT) of the tibia was performed on a 64-row scanner 42 days after the operation. The extent of bone healing was estimated quantitatively by MDCT volumetry using a commercially available software programme (syngo Volume, Siemens, Germany).The volume of the entire defect (including all pixels from -100 to 3,000 HU), the nonconsolidated areas (-100 to 500 HU), and areas of osseous consolidation (500 to 3,000 HU) were assessed and the extent of consolidation was calculated. Histomorphometry served as the reference standard. The extent of osseous consolidation in MDCT volumetry ranged from 19 to 92% (mean 65.4 {+-} 18.5%). There was a significant correlation between histologically visible newly formed bone and the extent of osseous consolidation on MDCT volumetry (r = 0.82, P < 0.0001). A significant negative correlation was detected between osseous consolidation on MDCT and histological areas of persisting defect (r = -0.9, P < 0.0001). MDCT volumetry is a promising tool for noninvasive monitoring of bone healing, showing excellent correlation with histomorphometry. (orig.)

Quantification and visualization of alveolar bone resorption from 3D dental CT images

Energy Technology Data Exchange (ETDEWEB)

Nagao, Jiro; Mori, Kensaku; Kitasaka, Takayuki; Suenaga, Yasuhito [Nagoya University, Graduate School of Information Science, Nagoya (Japan); Yamada, Shohzoh; Naitoh, Munetaka [Aichi-Gakuin University, School of Dentistry, Nagoya (Japan)

2007-06-15

Purpose A computer aided diagnosis (CAD) system for quantifying and visualizing alveolar bone resorption caused by periodontitis was developed based on three-dimensional (3D) image processing of dental CT images. Methods The proposed system enables visualization and quantification of resorption of alveolar bone surrounding and between the roots of teeth. It has the following functions: (1) vertical measurement of the depth of resorption surrounding the tooth in 3D images, avoiding physical obstruction; (2) quantification of the amount of resorption in the furcation area; and (3) visualization of quantification results by pseudo-color maps, graphs, and motion pictures. The resorption measurement accuracy in the area surrounding teeth was evaluated by comparing with dentist's recognition on five real patient CT images, giving average absolute difference of 0.87 mm. An artificial image with mathematical truth was also used for measurement evaluation. Results The average absolute difference was 0.36 and 0.10 mm for surrounding and furcation areas, respectively. The system provides an intuitive presentation of the measurement results. Conclusion Computer aided diagnosis of 3D dental CT scans is feasible and the technique is a promising new tool for the quantitative evaluation of periodontal bone loss. (orig.)

Subtraction radiography and computer assisted densitometric analyses of standardized radiographs. A comparison study with /sup 125/I absorptiometry

Energy Technology Data Exchange (ETDEWEB)

Ortmann, L.F.; Dunford, R.; McHenry, K.; Hausmann, E.

1985-01-01

A standardized radiographic series of incrementally increasing alveolar crestal defects in skulls were subjected to analyses by subtraction radiography and computer assisted quantitative densitometric analysis. Subjects were able to detect change using subtraction radiography in alveolar bone defects with bone loss in the range of 1-5 percent as measured by /sup 125/I absorptiometry. Quantitative densitometric analyses utilizing radiographic pairs adjusted for differences in contrast (gamma corrected) can be used to follow longitudinal changes at a particular alveolar bone site. Such measurements correlate with change observed by /sup 125/I absorptiometry (r=0.82-0.94). (author).

Bone-Implant Contact around Crestal and Subcrestal Dental Implants Submitted to Immediate and Conventional Loading

Directory of Open Access Journals (Sweden)

Ana Emília Farias Pontes

2014-01-01

Full Text Available The present study aims to evaluate the influence of apicocoronal position and immediate and conventional loading in the percentage of bone-implant contact (BIC. Thus, 36 implants were inserted in the edentulous mandible from six dogs. Three implants were installed in each hemimandible, in different positions in relation to the ridge: Bone Level (at crestal bone level, Minus 1 (one millimeter apical to crestal bone, and Minus 2 (two millimeters apical to crestal bone. In addition, each hemimandible was submitted to a loading protocol: immediate (prosthesis installed 24 hours after implantation or conventional (prosthesis installed 120 days after implantation. Ninety days after, animals were killed, and implant and adjacent tissues were prepared for histometric analysis. BIC values from immediate loaded implants were 58.7%, 57.7%, and 51.1%, respectively, while conventional loaded implants were 61.8%, 53.8%, and 68.4%. Differences statistically significant were not observed among groups (P=0.10, ANOVA test. These findings suggest that different apicocoronal positioning and loading protocols evaluated did not interfere in the percentage of bone-implant contact, suggesting that these procedures did not jeopardize osseointegration.

Visual and quantitative approach to bone marrow foci of increased glucose uptake on PET/CT in a case of aplastic anaemia

Energy Technology Data Exchange (ETDEWEB)

Cicone, F. [Sant' Andrea Hospital, Univ. La Sapienza, Rome (Italy). Nuclear Medicine Dept.; Centre Hospitalier Univ. Vaudois (Switzerland). Nuclear Medicine; Lausanne Univ. (Switzerland); Stalder, M. [Institut Central des Hopitaux Valaisans, Sion (Switzerland). Service of Hematology; Cairoli, A. [Centre Hospitalier Univ. Vaudois (Switzerland). Service of Hematology; Lausanne Univ. (Switzerland); Bischof Delaloye, A.; Prior, J.O. [Centre Hospitalier Univ. Vaudois (Switzerland). Nuclear Medicine; Lausanne Univ. (Switzerland); Geiger, D.

2010-07-01

This case report shows the clinical impact of a FDG-PET/CT in the assessment of bone marrow (BM) of a patient with aplastic anemia. The feasibility of a quantitative approach to BM intensities on FDG-PET is also discussed. In the authors' opinion, a deeper understanding of the factors that might independently affect FDG uptake and the definition of normal ranges of BM SUV (standardized uptake value) might help to interpret PET/CT images. Further research is needed to understand the physio-pathological basis of FDG uptake in BM and the potential value of its quantification. The analysis of the bone marrow on PET/CT is an interesting field of research. A PET/CT scan contributed to differential diagnosis in a patient with suspected bone marrow aplasia for guiding bone marrow biopsies.

Visual and quantitative approach to bone marrow foci of increased glucose uptake on PET/CT in a case of aplastic anaemia

International Nuclear Information System (INIS)

Cicone, F.; Stalder, M.; Bischof Delaloye, A.; Prior, J.O.; Geiger, D.

2010-01-01

This case report shows the clinical impact of a FDG-PET/CT in the assessment of bone marrow (BM) of a patient with aplastic anemia. The feasibility of a quantitative approach to BM intensities on FDG-PET is also discussed. In the authors' opinion, a deeper understanding of the factors that might independently affect FDG uptake and the definition of normal ranges of BM SUV (standardized uptake value) might help to interpret PET/CT images. Further research is needed to understand the physio-pathological basis of FDG uptake in BM and the potential value of its quantification. The analysis of the bone marrow on PET/CT is an interesting field of research. A PET/CT scan contributed to differential diagnosis in a patient with suspected bone marrow aplasia for guiding bone marrow biopsies.

SPECT/spiral-CT hybrid imaging in unclear foci of increased bone metabolism: a case report

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Roemer, W.; Kuwert, T. [Nuklearmedizinische Klinik, Friedrich-Alexander-Univ. Erlangen/Nuernberg (Germany); Beckmann, M.W. [Frauenklinik, Friedrich-Alexander-Univ. Erlangen/Nuernberg (Germany); Forst, R. [Lehrstuhl fuer Orthopaedie mit Orthopaedischer Chirurgie, Friedrich-Alexander Univ. Erlangen/Nuernberg (Germany); Bautz, W. [Radiologisches Inst., Friedrich-Alexander-Univ. Erlangen/Nuernberg (Germany)

2005-07-01

In bone scintigraphy, the differentiation between degenerative processes and bone metastases is still difficult. Therefore, additional radiological studies are regularly needed after bone scintigraphy. The now introduced hybrid-cameras combining single-photon emission computed tomography (SPECT) and spiral-CT are unique in the sense that they offer the opportunity to correlate the functional information with morphology in one session. We herein present two patients in whom this technological setup allowed a definite diagnosis in scintigraphically unclear vertebral lesions. In a patient with breast cancer, hypermetabolic lesions were clearly correlated with osteolyses. In another patient with synovial carcinoma, spondylosis and spondylarthrosis caused focal tracer uptake in the lumbar spine. In addition to an improved diagnostic accuracy, SPECT/Spiral-CT will considerably abbreviate the diagnostic process. (orig.)

SPECT/spiral-CT hybrid imaging in unclear foci of increased bone metabolism: a case report

International Nuclear Information System (INIS)

Roemer, W.; Kuwert, T.; Beckmann, M.W.; Forst, R.; Bautz, W.

2005-01-01

In bone scintigraphy, the differentiation between degenerative processes and bone metastases is still difficult. Therefore, additional radiological studies are regularly needed after bone scintigraphy. The now introduced hybrid-cameras combining single-photon emission computed tomography (SPECT) and spiral-CT are unique in the sense that they offer the opportunity to correlate the functional information with morphology in one session. We herein present two patients in whom this technological setup allowed a definite diagnosis in scintigraphically unclear vertebral lesions. In a patient with breast cancer, hypermetabolic lesions were clearly correlated with osteolyses. In another patient with synovial carcinoma, spondylosis and spondylarthrosis caused focal tracer uptake in the lumbar spine. In addition to an improved diagnostic accuracy, SPECT/Spiral-CT will considerably abbreviate the diagnostic process. (orig.)

Two and three-dimensional morphometric analysis of trabecular bone using X-ray microtomography (μCT)

International Nuclear Information System (INIS)

Silva, Alessandro Marcio Hakme da; Silva, Orivaldo Lopes da; Silva Junior, Nelson Ferreira da; Alves, Jose Marcos

2014-01-01

Introduction: trabecular bones have a porous microstructure and can be modeled as linear elastic solids, heterogeneous and anisotropic. In the literature, few investigations have compared the two- dimensional (2D) and three-dimensional (3D) morphometric analyses of cancellous bone. Methods: In this investigation eighteen cylindrical samples of cancellous bone (10 mm of diameter and 20 mm of height) were obtained from six bovine head femurs, with similar values for the weight and age, of the same race and gender. The samples were harvested and freeze at - 20 °C before carrying out the micro CT analysis. The CT-Analyzer software was used to measure in three directions (superior-inferior, lateral-medial and anterior-posterior) parameters such as trabecular thickness, trabecular separation, trabecular number and the eigenvalues of the fabric tensor (M). Results: the Comparison of 2D and 3D analyses for the parameters: 2D (plate model) trabecular thickness, trabecular separation and trabecular number were statistically different (p = 0) showing that measurements are not similar to the 3D ones. However, 2D (rod model) trabecular thickness and 3D trabecular thickness measurements presented no significant difference (p = 0.26). The eigenvalues show that the bovine trabecular microstructure has a tendency to transversally isotropic symmetry. Discussion: The method proved to be quite interesting for the characterization of the bone structure through 3D measurements of trabecular bone morphometric parameters in the three possible directions of loading. The results show that x-ray microtomography (μCT) is a technique of great potential for characterization and generating bone quality parameters for the diagnosis of bone metabolism diseases. (author)

Two and three-dimensional morphometric analysis of trabecular bone using X-ray microtomography (μCT)

Energy Technology Data Exchange (ETDEWEB)

Silva, Alessandro Marcio Hakme da; Silva, Orivaldo Lopes da; Silva Junior, Nelson Ferreira da, E-mail: alhakme@sc.usp.br [Universidade de Sao Paulo (EESC/FMRP/IQSC/USP), Sao Carlos, SP (Brazil); Alves, Jose Marcos [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Escola de Engenharia. Departamento de Engenharia Eletrica e Computacao

2014-07-01

Introduction: trabecular bones have a porous microstructure and can be modeled as linear elastic solids, heterogeneous and anisotropic. In the literature, few investigations have compared the two- dimensional (2D) and three-dimensional (3D) morphometric analyses of cancellous bone. Methods: In this investigation eighteen cylindrical samples of cancellous bone (10 mm of diameter and 20 mm of height) were obtained from six bovine head femurs, with similar values for the weight and age, of the same race and gender. The samples were harvested and freeze at - 20 °C before carrying out the micro CT analysis. The CT-Analyzer software was used to measure in three directions (superior-inferior, lateral-medial and anterior-posterior) parameters such as trabecular thickness, trabecular separation, trabecular number and the eigenvalues of the fabric tensor (M). Results: the Comparison of 2D and 3D analyses for the parameters: 2D (plate model) trabecular thickness, trabecular separation and trabecular number were statistically different (p = 0) showing that measurements are not similar to the 3D ones. However, 2D (rod model) trabecular thickness and 3D trabecular thickness measurements presented no significant difference (p = 0.26). The eigenvalues show that the bovine trabecular microstructure has a tendency to transversally isotropic symmetry. Discussion: The method proved to be quite interesting for the characterization of the bone structure through 3D measurements of trabecular bone morphometric parameters in the three possible directions of loading. The results show that x-ray microtomography (μCT) is a technique of great potential for characterization and generating bone quality parameters for the diagnosis of bone metabolism diseases. (author)

Digital subtraction imaging in cardiac investigations

International Nuclear Information System (INIS)

Partridge, J.B.; Dickinson, D.F.

1984-01-01

The role of digital subtraction imaging (DSI) in the investigation of heart disease in patients of all ages, including neonates, was evaluated by the addition of a continuous fluoroscopy system to an existing, single-plane catheterisation laboratory. In some situations, DSI provided diagnostic images where conventional radiography could not and, in general, provided images of comparable quality to cineangiography. The total dose of contrast medium was usually less than that which would have been required for biplane cineangiography and the dose of radiation was always less. Digital subtraction imaging can make a significant contribution to the investigation of congenital heart disease and has some useful features in the study of acquired heart disease. (author)

Comparative study of conventional and ultrasonically-assisted bone drilling.

Science.gov (United States)

Alam, K; Ahmed, Naseer; Silberschmidt, V V

2014-01-01

Bone drilling is a well-known surgical procedure in orthopaedics and dentistry for fracture treatment and reconstruction. Advanced understanding of the mechanics of the drill-bone interaction is necessary to overcome challenges associated with the process and related postoperative complications. The aim of this study was to explore the benefits of a novel drilling technique, ultrasonically-assisted drilling (UAD), and its possible utilization in orthopaedic surgeries. The study was performed by conducting experiments to understand the basic mechanics of the drilling process using high speed filming of the drilling zone followed by measurements to quantify thrust force, surface roughness and cracking of the bone near the immediate vicinity of the hole with and without ultrasonic assistance. Compared to the spiral chips produced during conventional drilling (CD), UAD was found to break the chips in small pieces which facilitated their fast evacuation from the cutting region. In UAD, lower drilling force and better surface roughness was measured in drilling in the radial and longitudinal axis of the bone. UAD produced crack-free holes which will enhance postoperative performance of fixative devices anchoring the bone. UAD may be used as a possible substitute for CD in orthopaedic clinics.

Head injury in childhood: comparison of sonography with the conventional X-ray and CT

International Nuclear Information System (INIS)

Steiner, S.; Riebel, T.; Nazarenko, O.; Bassir, C.; Steger, W.; Vogl, T.; Felix, R.

1996-01-01

Purpose: The purpose of our study was to compare the value of ultrasound, conventional X-ray diagnosis and CT in detecting skull fractures and intracranial haemorrhage in children suffering from a head injury. Material and methods: We examined 210 children who had a head injury. In all cases the calvarium was investigated by ultrasound using a 7.0 MHz linear transducer. In children with an open fontanel (n=190) the cerebrum was screened additionally by ultrasound following a standard protocol. The sonographic findings were correlated to the X-ray examination (n=21) and CT (n=13). Results: Ultrasound enabled diagnosis of linear calvarial fractures (n=29), depressed fratures (n=6) and intracranial haemorrhage (n=8). X-Ray and XT examination confirmed the diagnosis of linear calvarial fractures in 16 cases, of depressed fractures in 6 cases. CT confirmed the sonographic diagnosis of intracranial haemorrhage in 8 cases. Conclusion: Ultrasound as a primary method can replace the conventional X-ray in detecting calvarial fracture and posttraumatic sequelae. Additional CT examination depends on the sonographic and neurological status. (orig.) [de

Motion subtraction of the larynx using digital radiography

International Nuclear Information System (INIS)

Kumakawa, Kohzoh; Miyakawa, Kouichi

1990-01-01

The development of digital radiography (DR) has made it possible to analyze the contour of the laryngeal soft tissue structures in more detail than the conventional screen-film method. The authors first used the DR system for time subtraction of the larynx during inspiration and phonation. The images are acquired by means of frontal tomography of the larynx using the imaging plate during inspiration and phonation separately, and stored into the memory of the DR system. The thickness of the slices is 5.0 mm. Time subtraction between the mask image during inspiration and the live image during phonation is performed using digital processing on CRT. Superimposing the two images at the upper trachea and the thyroid cartilage of the same depth, makes it possible to measure movement of the vocal cord and false vocal cord quantitatively in three dimensions. The authors named this time subtraction as motion subtraction of the larynx. This motion subtraction image can be obtained by on-line digital processing without complicated development technique, but has so high spatial resolution. This image processing seems to be useful in functional radiographic analysis of laryngeal diseases. (author)

Intravenous digital subtraction angiography of transplanted kidney artery

International Nuclear Information System (INIS)

Tessier, J.P; Teyssou, H.; Verdier, J.P.; Tison, E.; Meyblum, J.; Marchal, M.

1986-01-01

Results of 351 intravenous digital subtraction angiographs (AN) of transplanted kidneys emphasized reliability of this examination for detection of renal artery stenosis. A prospective study of 219 patients (188 interpretable AN) showed significant stenosis of grafted artery in 22% of cases: 17% of the 126 patients with normal blood pressure and 34% of the 62 cases of hypertension. Digital subtraction allows, with a single injection, assessment of renal artery, nephrogram and excretory cavities, but it is not a substitute for conventional intravenous urography 1 to 2 months after grafting [fr

In vivo longitudinal micro-CT study of bent long limb bones in rat offspring.

Science.gov (United States)

De Schaepdrijver, Luc; Delille, Peter; Geys, Helena; Boehringer-Shahidi, Christian; Vanhove, Christian

2014-07-01

Micro-computed X-ray tomography (micro-CT) has been reported as a reliable method to assess ex vivo rat and rabbit fetal skeletons in embryo-fetal developmental toxicity studies. Since micro-CT is a non-invasive imaging modality it has the potential for longitudinal, in vivo investigation of postnatal skeletal development. This is the first paper using micro-CT to assess the reversibility of drug-induced bent long bones in a longitudinal study from birth to early adulthood in rat offspring. Analysis of the scans obtained on postnatal Day 0, 7, 21 and 80 showed complete recovery or repair of the bent long limb bones (including the scapula) within the first 3 weeks. When assessing risk the ability to demonstrate recovery is highly advantageous when interpreting such transient skeletal change. In summary, in vivo micro-CT of small laboratory animals can aid in non-clinical safety assessment, particularly for specific mechanistic purposes or to address a particular concern in developmental biology. Copyright © 2014 Elsevier Inc. All rights reserved.

Low-dose CT detects more progression of bone formation in comparison to conventional radiography in patients with ankylosing spondylitis: results from the SIAS cohort.

Science.gov (United States)

de Koning, Anoek; de Bruin, Freek; van den Berg, Rosaline; Ramiro, Sofia; Baraliakos, Xenofon; Braun, Juergen; van Gaalen, Floris A; Reijnierse, Monique; van der Heijde, Désirée

2018-02-01

To compare the CT Syndesmophyte Score (CTSS) for low-dose CT (ldCT) with the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS) for conventional radiographs (CR) in patients with ankylosing spondylitis (AS). Patients with AS in the Sensitive Imaging in Ankylosing Spondylitis cohort had lateral cervical and lumbar spine CR and whole spine ldCT at baseline and 2 years. CR and ldCT images were scored by two readers, paired by patient, blinded to time order, per imaging modality. For the total score analysis, we used average scores of readers per corner on CR or quadrant on ldCT. For the syndesmophyte analysis we used individual reader and consensus scores, regarding new or growing syndesmophyte at the same corner/quadrant. 50 patients were included in the syndesmophyte analysis and 37 in the total score analysis. Mean (SD) status scores for mSASSS (range 0-72) and CTSS (range 0-552) at baseline were 17.9 (13.8) and 161.6 (126.6), and mean progression was 2.4 (3.8) and 17.9 (22.1). Three times as many patients showed new or growing syndesmophytes at ≥3 quadrants on ldCT compared with ≥3 corners on CR for individual readers; for consensus this increased to five times. In 50 patients, 36 new or growing syndesmophytes are seen on CR compared with 151 on ldCT, most being found in the thoracic spine. ldCT, covering the whole spine, detects more progression in the form of new and growing syndesmophytes in patients with AS compared with CR, which is limited to the cervical and lumbar spine. Most progression occurred in the thoracic spine. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Semicircular canal dehiscence: Frequency and distribution on temporal bone CT and its relationship with the clinical outcomes

International Nuclear Information System (INIS)

Elmali, Muzaffer; Polat, Ahmet Veysel; Kucuk, Harun; Atmaca, Sinan; Aksoy, Ahmet

2013-01-01

Purpose: In this study, we aimed to investigate the frequency of SCD and its distribution and relationship with clinical outcomes on thin-section CT of the temporal bone. Materials and methods: Digital temporal bone CT images of 850 consecutive patients (1700 temporal bone CTs, 5100 SCs) who presented with a range of complaints such as vertigo, deafness, ear pain, fullness, and discharge between January 2008 and December 2011 were re-evaluated. Axial and oblique coronal reconstruction images of the temporal bone were made with a reconstruction thickness of 0.5 mm. Additionally, superior SC was evaluated in two perpendicular planes. Results: Out of 850 patients, 70 had completely normal temporal bone CT. Ninety-three patients had at least one SCD. In the temporal bone-based evaluation, 119 (26 bilateral, 67 unilateral) of 1700 temporal bones (7%) showed dehiscence. The SC-based evaluation revealed 125 SCD (2.5%) in 5100 SCs. The total number and rates of SCD were as follows: superior 103 (82.4%), posterior 13 (10.4%), and lateral nine (7.2%). Twenty of the 93 patients with SCD (21.5%) revealed no other findings on their temporal bone CTs. We determined a significant correlation between vestibular complaints, conductive hearing loss and SCD but there was no correlation between mixed, sensorineural hearing loss and SCD. Conclusion: We determined the frequency of SCD in 11% of patients and 7% of temporal bones. With regards to the distribution, the superior SC showed the highest dehiscence rate (82.4%). We found a significant correlation between vestibular symptoms, conductive hearing loss and SCD

Semicircular canal dehiscence: Frequency and distribution on temporal bone CT and its relationship with the clinical outcomes

Energy Technology Data Exchange (ETDEWEB)

Elmali, Muzaffer, E-mail: muzafel@yahoo.com.tr [Department of Radiology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey); Polat, Ahmet Veysel, E-mail: veyselp@hotmail.com [Department of Radiology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey); Kucuk, Harun, E-mail: hardrmd@yahoo.com [Department of Otorhinolaryngology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey); Atmaca, Sinan, E-mail: sinanatmaca@yahoo.com [Department of Otorhinolaryngology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey); Aksoy, Ahmet, E-mail: toxocara47@hotmail.com [Department of Otorhinolaryngology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey)

2013-10-01

Purpose: In this study, we aimed to investigate the frequency of SCD and its distribution and relationship with clinical outcomes on thin-section CT of the temporal bone. Materials and methods: Digital temporal bone CT images of 850 consecutive patients (1700 temporal bone CTs, 5100 SCs) who presented with a range of complaints such as vertigo, deafness, ear pain, fullness, and discharge between January 2008 and December 2011 were re-evaluated. Axial and oblique coronal reconstruction images of the temporal bone were made with a reconstruction thickness of 0.5 mm. Additionally, superior SC was evaluated in two perpendicular planes. Results: Out of 850 patients, 70 had completely normal temporal bone CT. Ninety-three patients had at least one SCD. In the temporal bone-based evaluation, 119 (26 bilateral, 67 unilateral) of 1700 temporal bones (7%) showed dehiscence. The SC-based evaluation revealed 125 SCD (2.5%) in 5100 SCs. The total number and rates of SCD were as follows: superior 103 (82.4%), posterior 13 (10.4%), and lateral nine (7.2%). Twenty of the 93 patients with SCD (21.5%) revealed no other findings on their temporal bone CTs. We determined a significant correlation between vestibular complaints, conductive hearing loss and SCD but there was no correlation between mixed, sensorineural hearing loss and SCD. Conclusion: We determined the frequency of SCD in 11% of patients and 7% of temporal bones. With regards to the distribution, the superior SC showed the highest dehiscence rate (82.4%). We found a significant correlation between vestibular symptoms, conductive hearing loss and SCD.

Template-based automatic extraction of the joint space of foot bones from CT scan

Science.gov (United States)

Park, Eunbi; Kim, Taeho; Park, Jinah

2016-03-01

Clean bone segmentation is critical in studying the joint anatomy for measuring the spacing between the bones. However, separation of the coupled bones in CT images is sometimes difficult due to ambiguous gray values coming from the noise and the heterogeneity of bone materials as well as narrowing of the joint space. For fine reconstruction of the individual local boundaries, manual operation is a common practice where the segmentation remains to be a bottleneck. In this paper, we present an automatic method for extracting the joint space by applying graph cut on Markov random field model to the region of interest (ROI) which is identified by a template of 3D bone structures. The template includes encoded articular surface which identifies the tight region of the high-intensity bone boundaries together with the fuzzy joint area of interest. The localized shape information from the template model within the ROI effectively separates the bones nearby. By narrowing the ROI down to the region including two types of tissue, the object extraction problem was reduced to binary segmentation and solved via graph cut. Based on the shape of a joint space marked by the template, the hard constraint was set by the initial seeds which were automatically generated from thresholding and morphological operations. The performance and the robustness of the proposed method are evaluated on 12 volumes of ankle CT data, where each volume includes a set of 4 tarsal bones (calcaneus, talus, navicular and cuboid).

Malignant pleural mesothelioma with heterologous osteoblastic differentiation: case report of the characteristic CT and bone scan findings

International Nuclear Information System (INIS)

Cho, Young Jun; Kim, Joung Sook; Kim, Ji Young; Choi, Soo Jeon; Choi, Sang Bong

2008-01-01

Malignant pleural mesothelioma is an uncommon neoplasm which is accompanied extremely rarely by osteoblastic heterologous elements. The CT manifestations of this tumor have been reported in several references. And, to our knowledge, only one case report provides a description of the bone scan findings. Here, we report the case of a rapidly progressing malignant pleural mesothelioma with heterologous osteoblastic elements. A CT scan reveals diffuse irregular pleural thickening and very coarse nodular calcifications along the right pleura and major fissure. A bone scan revealed an area of extensive increased radioactivity consistent with the pleural calcifications on the CT scan in the right hemithorax. A follow-up CT scan performed 40 days later suggests the presence of rapidly progressing nodular coarse calcifications

Malignant pleural mesothelioma with heterologous osteoblastic differentiation: case report of the characteristic CT and bone scan findings

Energy Technology Data Exchange (ETDEWEB)

Cho, Young Jun; Kim, Joung Sook; Kim, Ji Young; Choi, Soo Jeon; Choi, Sang Bong [Sanggye Paik Hospital, Inje University College of Medicine, Seoul (Korea, Republic of)

2008-06-15

Malignant pleural mesothelioma is an uncommon neoplasm which is accompanied extremely rarely by osteoblastic heterologous elements. The CT manifestations of this tumor have been reported in several references. And, to our knowledge, only one case report provides a description of the bone scan findings. Here, we report the case of a rapidly progressing malignant pleural mesothelioma with heterologous osteoblastic elements. A CT scan reveals diffuse irregular pleural thickening and very coarse nodular calcifications along the right pleura and major fissure. A bone scan revealed an area of extensive increased radioactivity consistent with the pleural calcifications on the CT scan in the right hemithorax. A follow-up CT scan performed 40 days later suggests the presence of rapidly progressing nodular coarse calcifications.

CT diagnosis of intramedulear lesions of the tubular bone

International Nuclear Information System (INIS)

Wagner-Manslau, C.; Feuerbach, S.; Biehl, T.

1985-01-01

Three cases are used to demonstrate that intramedullary masses of the tubular bones can be discovered using computered tomography even when changes in the plain film are lacking or discrete. However, it was not possible to differentiate between osteomyelitis, chondrosarcoma and enchondroma owing to the identical morphology of these three diseases. Consequently, CT does not allow any statement on type and dignity and histological clarification is indispensable. (orig./WU) [de

Relationships between age and microarchitectural descriptors of iliac trabecular bone determined by microCT.

Science.gov (United States)

Deguette, C; Ramond-Roquin, A; Rougé-Maillart, C

2017-06-01

Estimation of age at death is a major issue in anthropology. The main anthropological histological methods propose studying the architecture of cortical bone. In bone histomorphometry, researches on metabolic bone diseases have provided normative tables for trabecular bone volume (BV/TV) according to age and gender of individuals on trans-iliac bone biopsies. We have used microCT, a non-destructive tool for measuring bone volume and trabecular descriptors to compare the French tables to a series of forensic anthropological population and if the two iliac bones could be used interchangeably. Coxal bone of a personal forensic collection whose age and gender were known (DNA identification) were used. Bone samples, centered on the same area than bone biopsy. MicroCT (pixel size: 36μm) was used to measure BV/TV and morphometric trabecular parameters of microarchitecture. An adjusted Z-score was calculated for BV/TV to compare with normative tables and a right/left comparison of trabecular parameters was provided. Twenty-seven iliac bones, which 20 forming 10 complete pelvises, aged between 24 and 73y.o. (average of 47.7 y.o.) were used. All adjusted Z-score were within normal values. There was a strong positive correlation between right and left sides for Tb.Th, Tb.N and Tb.Sp, but an insignificant correlation was obtained for BV/TV. Normative tables between age and BV/TV are valid and therefore usable in anthropology. They may represent an alternative to determine the age at death. Nevertheless, it requires a precise technique that could be a drawback in current practice. Copyright © 2017 Elsevier Masson SAS. All rights reserved.