The usefulness of multiplanar reconstruction images in preoperative t-staging of advanced gastric cancer

International Nuclear Information System (INIS)

Koo, Young Baek; Kim, Suk; Lee, Jun Woo; Kim, Soo Jin; Choo, Ki Seok; Lee, Tae Hong; Moon, Tae Yong; Lee, Suk Hong; Jeon, Tae Yong

2004-01-01

The purpose of this study was to evaluate the performance of multidetector-row CT (MDCT) in the preoperative T-staging of patients with advanced gastric cancer. A total of 65 patients with an established diagnosis of advanced gastric cancer (T2 or more) were evaluated with MDCT. The protocol of MDCT consisted of high-quality (HQ) mode helical scanning with a slice thickness of 2.5 mm. The axial CT images were reconstructed with a slice thickness of 5 mm. MPR images were reconstructed from the raw axial data with a slice thickness of 5 mm. A comparison between the standard axial and axial MPR images was performed by two radiologists with regard to the evaluation of the tumor location and T-stage. These findings were compared with the pathologic and surgical findings. T-staging of the advanced stomach cancer was correct in 89% (58/65) and 69% (45/65) of the MPR images and axial images, respectively. The MPR images improved the detection rate (5 lesions) of the tumors and increased the accuracy of the T-staging (13 lesions) in comparison with the axial images. The MPR images are of greater diagnostic value for the evaluation of omental seeding (5 lesions: axial images, 9 lesions: MPR images), tumor location and extension. Multiplanar reconstruction (MPR) images provide increased confidence in the location and T-staging of certain cases of advanced gastric cancer, such as those in locations where CT images are susceptible to be affected by the difficulties associated with partial volume averaging. In this study, the MPR images provided more precise information about the tumor location and T-staging than the standard axial images in the preoperative evaluation of advanced gastric cancer

Diagnostic value of curved multiplanar reformatted images in multislice CT for the detection of resectable pancreatic ductal adenocarcinoma

International Nuclear Information System (INIS)

Fukushima, Hiromichi; Takada, Akira; Mori, Yoshimi; Suzuki, Kojiro; Sawaki, Akiko; Iwano, Shingo; Satake, Hiroko; Ota, Toyohiro; Ishigaki, Takeo; Itoh, Shigeki; Ikeda, Mitsuru

2006-01-01

The purpose of this study was to assess the usefulness of curved multiplanar reformatted (MPR) images obtained by multislice CT for the depiction of the main pancreatic duct (MPD) and detection of resectable pancreatic ductal adenocarcinoma. This study included 28 patients with pancreatic carcinoma (size range 12-40 mm) and 22 without. Curved MPR images with 0.5-mm continuous slices were generated along the long axis of the pancreas from pancreatic-phase images with a 0.5- or 1-mm slice thickness. Seven blinded readers independently interpreted three sets of images (axial images, curved MPR images, and both axial and curved MPR images) in scrolling mode. The depiction of the MPD and the diagnostic performance for the detection of carcinoma were statistically compared among these images. MPR images were significantly superior to axial images in depicting the MPD, and the use of both axial and MPR images resulted in further significant improvements. For the detection of carcinoma, MPR images were equivalent to axial images, and the diagnostic performance was significantly improved by the use of both axial and MPR images. High-resolution curved MPR images can improve the depiction of the MPD and the diagnostic performance for the detection of carcinoma compared with axial images alone. (orig.)

Reconstruction of a ring applicator using CT imaging: impact of the reconstruction method and applicator orientation

DEFF Research Database (Denmark)

Hellebust, Taran Paulsen; Tanderup, Kari; Bergstrand, Eva Stabell

2007-01-01

in multiplanar reconstructed images (MPR) and (3) library plans, using pre-defined applicator geometry (LIB). The doses to the lead pellets were calculated. The relative standard deviation (SD) for all reconstruction methods was less than 3.7% in the dose points. The relative SD for the LIB method...

The significance of multi-slice helical CT multiplanar reconstruction in the diagnoses of laryngeal carcinoma

International Nuclear Information System (INIS)

Li Lin; Luo Dehong; Zhou Chunwu; Zhao Xinming; Jiang Liming; Huang Yao; Jiang Lingxia; Li Jing; Wu Ning

2006-01-01

Objective: To evaluate the significance of multi-slice helical CT with multiplanar reconstruction in laryngeal carcinoma. Methods: Thirty-five patients with laryngeal carcinoma were studied by helical CT, MPR were subsequently done. The lesion extent of the axial image findings, MPR findings and the combined image findings were compared with the pathological results respectively. The data were statistically analyzed. Results: In the evaluation of the anterior commissure, the axial image findings, MPR findings and the combined image findings were 82.9%, 68.6% and 91.4% in accuracy respectively, the results were statistically different (P 0.05). The combined images were superior to the axial images and the MPR images in sensitivity, specificity and accuracy of the lesion extent. Conclusion: The axial images could show the shape, size, extension of the tumor and the lymphadenopathy, MPR images displayed the shape, size and extension roundly and directly, they were the supplement for the axial images. Axial images combined with MPR could improve the accuracy in the diagnoses of laryngeal carcinoma. (authors)

Diagnosis of Peripheral Lung Lesions via Conventional Flexible Bronchoscopy with Multiplanar CT Planning

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Marianne Anastasia De Roza

2016-01-01

Full Text Available Background. Conventional flexible bronchoscopy has limited sensitivity in the diagnosis of peripheral lung lesions and is dependent on lesion size. However, advancement of CT imaging offers multiplanar reconstruction facilitating enhanced preprocedure planning. This study aims to report efficacy and safety while considering the impact of patient selection and multiplanar CT planning. Method. Prospective case series of patients with peripheral lung lesions suspected of having lung cancer who underwent flexible bronchoscopy (forceps biopsy and lavage. Endobronchial lesions were excluded. Patients with negative results underwent CT-guided transthoracic needle aspiration, surgical biopsy, or clinical-radiological surveillance to establish the final diagnosis. Results. 226 patients were analysed. The diagnostic yield of bronchoscopy was 80.1% (181/226 with a sensitivity of 84.2% and specificity of 100%. In patients with a positive CT-Bronchus sign, the diagnostic yield was 82.4% compared to 72.8% with negative CT-Bronchus sign (p=0.116. Diagnostic yield was 84.9% in lesions > 20 mm and 63.0% in lesions ≤ 20 mm (p=0.001. Six (2.7% patients had transient hypoxia and 2 (0.9% had pneumothorax. There were no serious adverse events. Conclusion. Flexible bronchoscopy with appropriate patient selection and preprocedure planning is more efficacious in obtaining a diagnosis in peripheral lung lesions compared to historical data. This trial is registered with ClinicalTrials.gov Identifier: NCT01374542.

Demonstration of the pulmonary interlobar fissures on multiplanar reformatted images with 64-slices spiral CT

International Nuclear Information System (INIS)

Wang Yafei; Chen Yerong; Shan Xiuhong; Tang Zhiyang; Ni Enzhen; Huang Hao; Wu Shuchun

2009-01-01

Objective: To determine the optimal orientation and slice thickness of reformatted images to visualize the interlobar fissures on multiplanar reformation (MPR) images and to recommend MPR imaging protocal for visualizing interlobar fissures in clinical practise. Methods: 64-slices CT scans of chest were obtained in 300 patients without pulmonary diseases. Axial, sagittal and coronal images were reformatted at 1, 2, 3, 7 mm slice thickness respectively from the raw volume data. Three experienced radiologists evaluated all of the MPR images in the lung window and compared the differences in visualization of the interlohar fissures among the three reformatted orientations and at the different slice thicknesses with Fisher test and Friedman test. Results: Fissures on sagittal MPR images using 1, 2, 3, and 7 mm reformatted slice thickness appeared as a fine line and the preference value analysis showed the MPR images with a 3 mm reformatted slice thickness is the best for visualizing the interlobar fissure. Compared to the sagittal orientation, the coronal was not as good and the axial was the worst among the three orientations. The coronal images with a 3 mm reformatted slice thickness were slightly inferior to sagittal images. The right horizontal fissures were observed as a fine line in all coronal image in 94.0% (282)of cases and in some of the images in 6.0% (18) of cases, the right oblique fissures were displayed as a fine line in coronal images in 2.3% (7) of cases and in some images in 85.0% (255) of cases, the left oblique fissures were displayed as a fine line in some coronal images in 35.7% (107) of cases and displayed as a coarse line in 64.3% (193) of cases. On axial MPR images using 3 mm reformation slice thickness, the right oblique fissures and the left oblique fissures were displayed as a fine line in some axial images in 79.3% (238) and 81.0% (243) of cases respectively, none of the images showed horizontal fissures as a fine line. There was

Can independent coronal multiplanar reformatted images obtained using state-of-the-art MDCT scanners be used for primary interpretation of MDCT of the abdomen and pelvis? A feasibility study

International Nuclear Information System (INIS)

Sebastian, Sunit; Kalra, Mannudeep K.; Mittal, Pardeep; Saini, Sanjay; Small, William C.

2007-01-01

Purpose: To evaluate if coronal reformatted images can be used for primary interpretation of MDCT of the abdomen and pelvis using 64-slice MDCT. Materials and methods: IRB approval was obtained. We reviewed MDCT studies of the abdomen and pelvis of 220 consecutive patients performed with 64 row MDCT with constant scanning parameters. Based on a 0.625 mm raw data set, transverse images were reconstructed at 5 mm and coronal images at 3 mm using standard reconstruction algorithms. Reader familiarity was achieved by simultaneous evaluation of transverse and coronal reformats in an initial group of 20 separate cases for findings in consensus. Two subsequent phases of image analysis were then performed in two groups of 100 patients each. In the first phase two radiologists evaluated the added utility of simultaneous review of MDCT of transverse and coronal reformatted images over transverse images alone in 100 consecutive patients referred for MDCT of the abdomen and pelvis. In the second phase, the same radiologists evaluated whether coronal multiplanar reformats could be used for primary interpretation of MDCT of the abdomen and pelvis in a separate but similar cohort of 100 consecutive abdominopelvic MDCT studies. The number of lesion(s), their location, size of smallest lesion, presence of artifacts and likely diagnosis were noted at each image interpretation. Image quality and confidence for interpretation was evaluated using five-point and three-point scale, respectively. The time required for primary interpretation of coronal reformats and transverse images were recorded. Statistical analysis was performed using Wilcoxon signed rank test. Results: Both readers detected additional findings (n = 37, 35), respectively, on simultaneous review of transverse and coronal reformats as compared with transverse images alone (p < 0.001). Excellent interobserver agreement was noted (r = 0.94-0.96). Both readers detected additional findings (n = 62, 53), respectively, on

Three-dimensional short-range MR angiography and multiplanar reconstruction images in the evaluation of neurovascular compression in hemifacial spasm

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Choi, Woo Suk; Kim, Eui Jong; Lee, Jae Gue; Rhee, Bong Arm [Kyunghee Univ. Hospital, Seoul (Korea, Republic of)

1998-08-01

To evaluate the diagnostic efficacy of three-dimensional(3D) short-range MR angiography(MRA) and multiplanar reconstruction(MPR) imaging in hemifacial spasm(HS). Materials and Methods : Two hundreds patients with HS were studied using a 1.5T MRI system with a 3D time-of-flight(TOF) MRA sequence. To reconstruct short-range MRA, 6-10 source images near the 7-8th cranial nerve complex were processed using a maximum-intensity projection technique. In addition, an MPR technique was used to investigate neurovascular compression. We observed the relationship between the root-exit zone(REZ) of the 7th cranial nerve and compressive vessel, and identified the compressive vessels on symptomatic sides. To investigate neurovascular contact, asymptomatic contralateral sides were also evaluated. Results : MRI showed that in 197 of 200 patients there was vascular compression or contact with the facial nerve REZ on symptomatic sides. One of the three remaining patients was suffering from acoustic neurinoma on the symptomatic side, while in two patients there were no definite abnormal findings.Compressive vessels were demonstrated in all 197 patients; 80 cases involved the anterior inferior cerebellar artery(AICA), 74 the posterior cerebellar artery(PICA), 13 the vertebral artery(VA), 16 the VA and AICA, eight the VA and PICA, and six the AICA and PICA. In all 197 patients, compressive vessels were reconstructed on one 3D short-range MRA image without discontinuation from vertebral or basilar arteries. 3D MPR studies provided additional information such as the direction of compression and course of the compressive vessel. In 31 patients there was neurovascular contact on the contralateral side at the 7-8th cranial nerve complex. Conclusion : Inpatients with HS, 3D short-range MRA and MPR images are excellent and very helpful for the investigation of neurovascular compression and the identification of compressive vessels.

Three-dimensional short-range MR angiography and multiplanar reconstruction images in the evaluation of neurovascular compression in hemifacial spasm

International Nuclear Information System (INIS)

Choi, Woo Suk; Kim, Eui Jong; Lee, Jae Gue; Rhee, Bong Arm

1998-01-01

To evaluate the diagnostic efficacy of three-dimensional(3D) short-range MR angiography(MRA) and multiplanar reconstruction(MPR) imaging in hemifacial spasm(HS). Materials and Methods : Two hundreds patients with HS were studied using a 1.5T MRI system with a 3D time-of-flight(TOF) MRA sequence. To reconstruct short-range MRA, 6-10 source images near the 7-8th cranial nerve complex were processed using a maximum-intensity projection technique. In addition, an MPR technique was used to investigate neurovascular compression. We observed the relationship between the root-exit zone(REZ) of the 7th cranial nerve and compressive vessel, and identified the compressive vessels on symptomatic sides. To investigate neurovascular contact, asymptomatic contralateral sides were also evaluated. Results : MRI showed that in 197 of 200 patients there was vascular compression or contact with the facial nerve REZ on symptomatic sides. One of the three remaining patients was suffering from acoustic neurinoma on the symptomatic side, while in two patients there were no definite abnormal findings.Compressive vessels were demonstrated in all 197 patients; 80 cases involved the anterior inferior cerebellar artery(AICA), 74 the posterior cerebellar artery(PICA), 13 the vertebral artery(VA), 16 the VA and AICA, eight the VA and PICA, and six the AICA and PICA. In all 197 patients, compressive vessels were reconstructed on one 3D short-range MRA image without discontinuation from vertebral or basilar arteries. 3D MPR studies provided additional information such as the direction of compression and course of the compressive vessel. In 31 patients there was neurovascular contact on the contralateral side at the 7-8th cranial nerve complex. Conclusion : Inpatients with HS, 3D short-range MRA and MPR images are excellent and very helpful for the investigation of neurovascular compression and the identification of compressive vessels

Frequency and types of fractures in maxillofacial traumas. Assessment using MDCT with multiplanar and 3D reconstructions

International Nuclear Information System (INIS)

Tomich, G.; Baigorria, P.; Orlando, N.; Mejico, M.; Costamagna, C.; Villavicencio, R.

2011-01-01

Introduction: Maxillofacial trauma (MFT) is a common reason for attendance at Emergency Departments. The complex anatomy of the facial bones requires multiplanar imaging techniques for a proper evaluation. Objectives. To describe frequency and types of fractures in a series of patients with MFT evaluated by multi-slice computed tomography (MDCT) with multiplanar and 3D reconstructions. Materials and Methods: Facial bone CTs ordered for MFT by the Emergency Department from June 2008 to December 2009 were retrospectively reviewed. The following data were obtained: age, gender, cause of trauma, presence and type of fractures. Patients were evaluated with an 8-channel MDCT. Multiplanar reconstructions were performed in all cases using high resolution bone window and soft tissue window, as well as 3D reconstructions. Results: One-hundred and thirty-seven CTs were performed for MFT: 78 (57%) showed 131 fractures. Of these 78 patients, 52 (66%) were males and 26 (34%) were females; mean age 33 years old (range: 14-90 yrs.). Causes: 58 % were injuries from traffic accidents; 24% were injuries from fights; 13% were sport injuries; and 7% were due to miscellaneous etiologies. Type and frequency of fractures: 18.3% were orbital floor fractures, 16% were maxillary sinus fractures, 15.3% were nasal fractures, 13% were jaw fractures, 9.2% were orbital fractures, and 12.3% were fractures of the zygomatic-malar complex; two cases of Le Fort II-III fractures were also observed. Conclusions: Fractures were more common in males, in the age range from 15 to 35 years old. Most fractures, and the most complex ones, were caused by traffic accidents. The most common fracture, either isolated or associated with other fractures, was the orbital floor fracture. (authors)

Reproducibility of Abdominal Aortic Aneurysm Diameter Measurement and Growth Evaluation on Axial and Multiplanar Computed Tomography Reformations

International Nuclear Information System (INIS)

Dugas, Alexandre; Therasse, Éric; Kauffmann, Claude; Tang, An; Elkouri, Stephane; Nozza, Anna; Giroux, Marie-France; Oliva, Vincent L.; Soulez, Gilles

2012-01-01

Purpose: To compare different methods measuring abdominal aortic aneurysm (AAA) maximal diameter (Dmax) and its progression on multidetector computed tomography (MDCT) scan. Materials and Methods: Forty AAA patients with two MDCT scans acquired at different times (baseline and follow-up) were included. Three observers measured AAA diameters by seven different methods: on axial images (anteroposterior, transverse, maximal, and short-axis views) and on multiplanar reformation (MPR) images (coronal, sagittal, and orthogonal views). Diameter measurement and progression were compared over time for the seven methods. Reproducibility of measurement methods was assessed by intraclass correlation coefficient (ICC) and Bland–Altman analysis. Results: Dmax, as measured on axial slices at baseline and follow-up (FU) MDCTs, was greater than that measured using the orthogonal method (p = 0.046 for baseline and 0.028 for FU), whereas Dmax measured with the orthogonal method was greater those using all other measurement methods (p-value range: <0.0001–0.03) but anteroposterior diameter (p = 0.18 baseline and 0.10 FU). The greatest interobserver ICCs were obtained for the orthogonal and transverse methods (0.972) at baseline and for the orthogonal and sagittal MPR images at FU (0.973 and 0.977). Interobserver ICC of the orthogonal method to document AAA progression was greater (ICC = 0.833) than measurements taken on axial images (ICC = 0.662–0.780) and single-plane MPR images (0.772–0.817). Conclusion: AAA Dmax measured on MDCT axial slices overestimates aneurysm size. Diameter as measured by the orthogonal method is more reproducible, especially to document AAA progression.

Quantification of resolution in multiplanar reconstructions for digital breast tomosynthesis

Science.gov (United States)

Vent, Trevor L.; Acciavatti, Raymond J.; Kwon, Young Joon; Maidment, Andrew D. A.

2016-03-01

Multiplanar reconstruction (MPR) in digital breast tomosynthesis (DBT) allows tomographic images to be portrayed in various orientations. We have conducted research to determine the resolution of tomosynthesis MPR. We built a phantom that houses a star test pattern to measure resolution. This phantom provides three rotational degrees of freedom. The design consists of two hemispheres with longitudinal and latitudinal grooves that reference angular increments. When joined together, the hemispheres form a dome that sits inside a cylindrical encasement. The cylindrical encasement contains reference notches to match the longitudinal and latitudinal grooves that guide the phantom's rotations. With this design, any orientation of the star-pattern can be analyzed. Images of the star-pattern were acquired using a DBT mammography system at the Hospital of the University of Pennsylvania. Images taken were reconstructed and analyzed by two different methods. First, the maximum visible frequency (in line pairs per millimeter) of the star test pattern was measured. Then, the contrast was calculated at a fixed spatial frequency. These analyses confirm that resolution decreases with tilt relative to the breast support. They also confirm that resolution in tomosynthesis MPR is dependent on object orientation. Current results verify that the existence of super-resolution depends on the orientation of the frequency; the direction parallel to x-ray tube motion shows super-resolution. In conclusion, this study demonstrates that the direction of the spatial frequency relative to the motion of the x-ray tube is a determinant of resolution in MPR for DBT.

[Fetal neurosonography using 3-dimensional multiplanar sonography].

Science.gov (United States)

Chaoui, R; Heling, K S; Kainer, F; Karl, K

2012-04-01

This review focuses on the examination of the fetal brain, using three-dimensional (3D) ultrasound and the multiplanar rendering mode (MPR). The routine examination of the brain is achieved with axial planes but a dedicated fetal neurosonogram requires additional coronal and sagittal views, in order to provide a complete view of the different brain structures. Because these planes are difficult to obtain under many conditions, the present paper shows how 3D MPR allows one to obtain 1 or multiple reconstructed images from a digital volume. The display can be either as orthogonal planes, tomographic planes with parallel slices or as one single plane of the region of interest, which can be selected by the examiner. This approach allows easily the demonstration of the corpus callosum, the cerebellar vermis, the three-horn view, the foetal hippocampus and other regions. In addition, early neurosonography of the developing brain from the 7th week of pregnancy onwards can be achieved. © Georg Thieme Verlag KG Stuttgart · New York.

Morphological and functional diagnosis in the head and neck with multiplanar spiral CT

International Nuclear Information System (INIS)

Lell, M.; Baum, U.; Noemayr, A.; Greess, H.; Lenz, M.; Bautz, W.; Koester, M.

1999-01-01

Purpose: To evaluate the improvement of multislice-spiral CT in the assessment of head and neck tumors. Material and methods: 80 patients with suspected tumor in the head and neck region were examined with MSCT (Somatom Plus 4 VZ) after the administration of i.v. contrast material. Slice collimation was 4x1 mm with a pitch factor of 6. Additional multiplanar reformations were calculated in each case. Results: The specific anatomy and pathways of tumor spread is difficult to demonstrate in cross-sectional imaging. Tumor infiltration of the base of the skull or the palate could be depicted or excluded on coronal MPR, additional coronal scanning was not necessary. The detection of pathologic lymph nodes was improved with MPR in 7 patients. Discussion: The exact determination of tumor margins is mandatory for modern therapy concepts of limited surgery. High resolution datasets are basis for reformations in arbitrary planes, making additional coronal scanning not necessary. Functional imaging of the larynx and hypopharynx improve the diagnostic accuracy of CT, a short scantime is necessary to reduce motion artifacts. Conclusive assessment of tumor infiltration, lymphatic spread and functional alterations is improved with MSCT. (orig.) [de

An evaluation of the regional cerebral blood flow (rCBF) measurement by xenon-enhanced dynamic CT with helical scanning technique and the functional imaging by multiplanar reconstruction (MPR). Fundamental study and clinical application

International Nuclear Information System (INIS)

Watanabe, Kenichi

1997-01-01

We evaluated the quantitative rCBF by xenon-enhanced dynamic CT with helical scanning technique on all brain regions, and also examined clinical usefulness of coronal and sagittal section images which are similar to SPECT images obtained by the functional multiplanar reconstitution (MPR) imaging of many successive flow maps. We used 14 clinical cases. The conventional xenon-enhanced CT was simple and ideal method to measure rCBF, however, it had disadvantages; it gives a few laminagraphical images or only the axial directional images, compared to SPECT or PET. There is a risk to overlook lesions out of the image or not to obtain the whole images of the lesion. Although the helical scanning technique has a methodological characteristics to use adjacent data for the image reconstitution, it is by no means inferior to the conventional method in the contrast resolution or the image resolution when the co-helical function and an appropriate reconstituted function were used. It has an advantage to scan all brain regions by only one cycle of scanning. Furthermore on making good use of the property that the helical scanning technique can give the successive data, we can observe rCBF by coronal and sagittal images when many flow maps were made up by reconstituted images of the narrow steps. This shows the clinical usefulness of this technique. One of the future problem to be solved is to decrease the exposure dose. (K.H.)

Investigation of reconstruction conditions in sagittal-plane multiplanar reconstruction of the temporal bone

International Nuclear Information System (INIS)

Suzuki, Miyako; Yoshikawa, Hiroshi; Hosokawa, Akira; Ichikawa, Ginichiro; Kobayashi, Kenichi; Ando, Ichiro

2002-01-01

In recent years, it has become possible to quickly obtain a large amount of 3D data with high continuity by helical CT scanning, in which the body is scanned continuously in a helical fashion. MPR (multiplanar reconstruction) can be performed using this data to generate images in arbitrary sectional planes, making it possible to obtain sagittal-plane images of the highest quality, which is useful for surgical planning. However, the procedures involved are rather complicated. Therefore, this study was conducted to investigate conditions for standardization of sagittal-plane MPR examinations performed using Xvigor CT scanners and Xtension. The results showed that a slice interval of 1 mm, no imaging filter, a zooming factor of 1.5, a window level of 350, and a window width of 3500 are the optimal imaging conditions. The stapes can be visualized in 70% of cases with sagittal-plane MPR based on axial images, and can be recognized at surgery in 75% or more of cases. Images of consistent quality can be obtained by standardizing the conditions for sagittal-plane MPR, which should prove advantageous in the clinical setting. (author)

A model-based radiography restoration method based on simple scatter-degradation scheme for improving image visibility

Science.gov (United States)

Kim, K.; Kang, S.; Cho, H.; Kang, W.; Seo, C.; Park, C.; Lee, D.; Lim, H.; Lee, H.; Kim, G.; Park, S.; Park, J.; Kim, W.; Jeon, D.; Woo, T.; Oh, J.

2018-02-01

In conventional planar radiography, image visibility is often limited mainly due to the superimposition of the object structure under investigation and the artifacts caused by scattered x-rays and noise. Several methods, including computed tomography (CT) as a multiplanar imaging modality, air-gap and grid techniques for the reduction of scatters, phase-contrast imaging as another image-contrast modality, etc., have extensively been investigated in attempt to overcome these difficulties. However, those methods typically require higher x-ray doses or special equipment. In this work, as another approach, we propose a new model-based radiography restoration method based on simple scatter-degradation scheme where the intensity of scattered x-rays and the transmission function of a given object are estimated from a single x-ray image to restore the original degraded image. We implemented the proposed algorithm and performed an experiment to demonstrate its viability. Our results indicate that the degradation of image characteristics by scattered x-rays and noise was effectively recovered by using the proposed method, which improves the image visibility in radiography considerably.

Thin-section multiplanar reformats from multidetector-row CT data: Utility for assessment of regional tumor extent in non-small cell lung cancer

International Nuclear Information System (INIS)

Higashino, Takanori; Ohno, Yoshiharu; Takenaka, Daisuke; Watanabe, Hirokazu; Nogami, Munenobu; Ohbayashi, Chiho; Yoshimura, Masahiro; Satouchi, Miyako; Nishimura, Yoshihiro; Fujii, Masahiko; Sugimura, Kazuro

2005-01-01

Purpose: To determine the clinical utility of thin-section multiplanar reformats (MPRs) from multidetector-row CT (MDCT) data sets for assessing the extent of regional tumors in non-small cell lung cancer (NSCLC) patients. Materials and methods: Sixty consecutive NSCLC patients, who were considered candidates for surgical treatment, underwent contrast-enhanced MDCT examinations, surgical resection and pathological examinations. All MDCT examinations were performed with a 4-detector row computed tomography (CT). From each raw CT data set, 5 mm section thickness CT images (routine CT), 1.25 mm section thickness CT images (thin-section CT) and 1.25 mm section thickness sagittal (thin-section sagittal MPR) and coronal images (thin-section coronal MPR) were reconstructed. A 4-point visual score was used to assess mediastinal, interlobar and chest wall invasions on each image set. For assessment of utility in routine clinical practice, mean reading times for each image set were compared by means of Fisher's protected least significant difference (PLSD) test. A receiver operator characteristic (ROC) analysis was performed to determine the diagnostic capability of each of the image data sets. Finally, sensitivity, specificity and accuracy of the reconstructed images were compared by McNemar test. Results: Mean reading times for thin-section sagittal and coronal MPRs were significantly shorter than those for routine CT and thin-section CT (p < 0.05). Areas under the curve (Azs) showing interlobar invasion on thin-section sagittal and coronal MPRs were significantly larger than that on routine CT (p = 0.03), and the Az on thin-section sagittal MPR was also significantly larger than that on routine CT (p = 0.02). Accuracy of chest wall invasion by thin-section sagittal MPR was significantly higher than that by routine CT (p = 0.04). Conclusion: Thin-section multiplanar reformats from multidetector-row CT data sets are useful for assessing the extent of regional tumors in non

Interpretation of Radiological Images: Towards a Framework of Knowledge and Skills

Science.gov (United States)

van der Gijp, A.; van der Schaaf, M. F.; van der Schaaf, I. C.; Huige, J. C. B. M.; Ravesloot, C. J.; van Schaik, J. P. J.; ten Cate, Th. J.

2014-01-01

The knowledge and skills that are required for radiological image interpretation are not well documented, even though medical imaging is gaining importance. This study aims to develop a comprehensive framework of knowledge and skills, required for two-dimensional and multiplanar image interpretation in radiology. A mixed-method study approach was…

CT Imaging of facial trauma. The role of different types of reconstruction. Part II - soft tissues

International Nuclear Information System (INIS)

Myga-Porosilo, J.; Sraga, W.; Borowiak, H.; Jackowska, Z.; Kluczewska, E.; Skrzelewski, S.

2011-01-01

Background: Injury to facial soft tissues as a complication of skeleton fractures is an important problem among patients with facial trauma. The aim of this work was to assess the value of multiplanar and three-dimensional (3D) reconstruction computed tomography (CT) images obtained by using multi-detector row technology in spiral data acquisition in patients with facial injuries of soft tissue. Material/Methods: Sixty-seven patients diagnosed with injury to the facial skeleton underwent a CT scan with the use of GE Hispeed Qx/i scanner. For each patient: a two-dimensional (2D) multiplanar reconstruction (MPR), maximum intensity projection (MIP), and 3D volume rendering (VR) were conducted. Post-injury lesions of soft tissues were assessed. During the assessment of the post-injury lesions of soft tissues, the following features were evaluated: Extra ocular muscle and fat tissue herniation through fractures in the medial and inferior orbital walls. Fluid in the sinuses and in the nasal cavity. Subcutaneous tissue emphysema. Results: For subcutaneous emphysema and sinus fluid imaging, both the axial and the 2D image reconstruction proved comparably effective. However, 2D reconstructions were superior to transverse plane images with regard to herniations into fractures of the inferior orbital wall. 3D reconstruction has no importance in diagnosing soft tissue injuries. Conclusions: Multiplanar CT reconstructions increase the effectiveness of imaging of orbital tissue herniations, especially in case of fractures in the inferior orbital wall. In suspected soft tissue herniations, as well as prior to surgical treatment, spiral CT with 2D multiplanar reconstructions should be the method of choice. (authors)

Multiplanar reconstruction computed tomography for diagnosis of scaphoid waist fracture union: a prospective cohort analysis of accuracy and precision

Energy Technology Data Exchange (ETDEWEB)

Hannemann, P.F.W.; Brouwers, L.; Gottgens, K.W.A.; Poeze, M.; Brink, P.R.G. [Maastricht University Medical Centre, Department of Surgery and Traumasurgery, PO Box 5800, Maastricht (Netherlands); Zee, D. van der; Stadler, A.; Weijers, R. [Maastricht University Medical Centre, Department of radiology, PO Box 5800, Maastricht (Netherlands)

2013-10-15

To examine reliability and validity concerning union of scaphoid fractures determined by multiplanar reconstruction computed tomography randomized at 6, 12, and 24 weeks after injury. We used Fleiss' kappa to measure the opinions of three observers reviewing 44 sets of computed tomographic scans of 44 conservatively treated scaphoid waist fractures. We calculated kappa for the extent of consolidation (0-24 %, 25-49 %, 50-74 %, or 75-100 %) on the transverse, sagittal and coronal views. We also calculated kappa for no union, partial union, and union, and grouped the results for 6, 12, and 24 weeks after injury. As the reference standard for union, CT scans were performed at a minimum of 6 months after injury to determine validity. Overall inter-observer agreement was found to be moderate ({kappa} = 0.576). No union ({kappa} = 0.791), partial union ({kappa} = 0.502), and union ({kappa} = 0.683) showed substantial, moderate, and substantial agreement, respectively. The average sensitivity of multiplanar reconstruction CT for diagnosing union of scaphoid waist fractures was 73 %. The average specificity was 80 %. Our results suggest that multiplanar reconstruction computed tomography is a reliable and accurate method for diagnosing union or nonunion of scaphoid fractures. However, inter-observer agreement was lower with respect to partial union. (orig.)

Multiplanar reconstruction computed tomography for diagnosis of scaphoid waist fracture union: a prospective cohort analysis of accuracy and precision

International Nuclear Information System (INIS)

Hannemann, P.F.W.; Brouwers, L.; Gottgens, K.W.A.; Poeze, M.; Brink, P.R.G.; Zee, D. van der; Stadler, A.; Weijers, R.

2013-01-01

To examine reliability and validity concerning union of scaphoid fractures determined by multiplanar reconstruction computed tomography randomized at 6, 12, and 24 weeks after injury. We used Fleiss' kappa to measure the opinions of three observers reviewing 44 sets of computed tomographic scans of 44 conservatively treated scaphoid waist fractures. We calculated kappa for the extent of consolidation (0-24 %, 25-49 %, 50-74 %, or 75-100 %) on the transverse, sagittal and coronal views. We also calculated kappa for no union, partial union, and union, and grouped the results for 6, 12, and 24 weeks after injury. As the reference standard for union, CT scans were performed at a minimum of 6 months after injury to determine validity. Overall inter-observer agreement was found to be moderate (κ = 0.576). No union (κ = 0.791), partial union (κ = 0.502), and union (κ = 0.683) showed substantial, moderate, and substantial agreement, respectively. The average sensitivity of multiplanar reconstruction CT for diagnosing union of scaphoid waist fractures was 73 %. The average specificity was 80 %. Our results suggest that multiplanar reconstruction computed tomography is a reliable and accurate method for diagnosing union or nonunion of scaphoid fractures. However, inter-observer agreement was lower with respect to partial union. (orig.)

Musculoskeletal applications of magnetic resonance imaging: Council on Scientific Affairs

International Nuclear Information System (INIS)

Harms, S.E.; Fisher, C.F.; Fulmer, J.M.

1989-01-01

Magnetic resonance imaging provides superior contrast, resolution, and multiplanar imaging capability, allowing excellent definition of soft-tissue and bone marrow abnormalities. For these reasons, magnetic resonance imaging has become a major diagnostic imaging method for the evaluation of many musculoskeletal disorders. The applications of magnetic resonance imaging for musculoskeletal diagnosis are summarized and examples of common clinical situations are given. General guidelines are suggested for the musculoskeletal applications of magnetic resonance imaging

Frecuencia y tipo de fracturas en traumatismos maxilofaciales: Evaluación con Tomografía Multislice con reconstrucciones multiplanares y tridimensionales Frequency and types of fractures in maxillofacial traumas: Assessment using MDCT with multiplanar and 3D reconstructions

OpenAIRE

Gabriela Tomich; Patricio Baigorria; Nicolás Orlando; Mariano Méjico; Cecilia Costamagna; Roberto Villavicencio

2011-01-01

Introducción. Los traumatismos maxilofaciales (TMF) representan un motivo de consulta común en los servicios de Urgencias. La compleja anatomía del macizo facial requiere de métodos de imágenes multiplanares para su correcta evaluación. Objetivos. Describir la frecuencia y tipos de fracturas en una serie de pacientes con TMF evaluados mediante tomografía computada multislice (TCMS) con reconstrucciones multiplanares y tridimensionales. Materiales y Métodos. Se revisaron en forma retrospectiva...

The spectrum of benign esophageal lesions: imaging findings

International Nuclear Information System (INIS)

Jang, Kyung Mi; Lee, Kyung Soo; Lee, Soon Jin; Kim, Eun A; Kim, Tae Sung; Han, Dae Hee; Shim, Young Mog

2002-01-01

Benign esophageal lesions occur in various diseases. Barium studies are useful for the evaluation of mucosal surface lesions but provide little information about the extramucosal extent of disease. Computed tomography and magnetic resonance imaging, on the other hand, permit the assessment of wall thickness, mediastinal involvement, adjacent lymphadenopathy, and distant spread. In diseases such as fibrovascular polyps, duplication cysts, scleroderma, trauma, caustic esophagitis, hiatal hernia, esophageal diverticulum, achalasia, and paraesophageal varices, the findings of imaging studies are specific, obviating the need for further invasive diagnostic work-up. The advent of helical computed tomography and its volume data set allows the acquisition of multiplanar images, and magnetic resonance imaging is useful both for this and for tissue characterization. Thus, multiplanar cross-sectional imaging further extends the role of imaging modalities to the evaluation of benign esophageal lesions. Through an awareness of the multiplanar cross-sectional appearances of various benign esophageal lesions, the radiologist can play an important role in the detection, diagnosis, further diagnostic planning, and treatment of the diseases in which they occur

The spectrum of benign esophageal lesions: imaging findings

Energy Technology Data Exchange (ETDEWEB)

Jang, Kyung Mi; Lee, Kyung Soo; Lee, Soon Jin; Kim, Eun A; Kim, Tae Sung; Han, Dae Hee; Shim, Young Mog [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2002-09-01

Benign esophageal lesions occur in various diseases. Barium studies are useful for the evaluation of mucosal surface lesions but provide little information about the extramucosal extent of disease. Computed tomography and magnetic resonance imaging, on the other hand, permit the assessment of wall thickness, mediastinal involvement, adjacent lymphadenopathy, and distant spread. In diseases such as fibrovascular polyps, duplication cysts, scleroderma, trauma, caustic esophagitis, hiatal hernia, esophageal diverticulum, achalasia, and paraesophageal varices, the findings of imaging studies are specific, obviating the need for further invasive diagnostic work-up. The advent of helical computed tomography and its volume data set allows the acquisition of multiplanar images, and magnetic resonance imaging is useful both for this and for tissue characterization. Thus, multiplanar cross-sectional imaging further extends the role of imaging modalities to the evaluation of benign esophageal lesions. Through an awareness of the multiplanar cross-sectional appearances of various benign esophageal lesions, the radiologist can play an important role in the detection, diagnosis, further diagnostic planning, and treatment of the diseases in which they occur.

CT Imaging of facial trauma. Role of different types of reconstruction. Part I - bones

International Nuclear Information System (INIS)

Myga-Porosilo, J.; Sraga, W.; Borowiak, H.; Jackowska, Z.; Kluczewska, E.; Skrzelewski, S.

2011-01-01

Background: Injury to the facial skeleton and the adjoining soft tissues is a frequently occurring condition. The main aim of this work was to assess the value of multiplanar and three-dimensional (3D) reconstruction computed tomography (CT) images obtained by using multi-detector row technology in spiral data acquisition in patients with facial skeleton injury. The authors attempted to answer the following questions: Are there particular mechanisms and types of injuries or locations of fractures which can be diagnosed significantly more effectively by conducting additional multiplanar image reconstructions? Do 3D image reconstructions contribute to the diagnostic process, to what extent? Compared to other imaging techniques, is the spiral CT data acquisition a more convenient for the patient and a faster investigation method of diagnosing post-injury lesions involving the facial skeleton? Material/Methods: Sixty-seven patients diagnosed with injury to the facial skeleton were referred for emergent CT scanning. Each patient underwent a CT scan with the use of a GE HiSpeed Qx/i scanner. The scans were conducted with the use of spiral data acquisition technique in the transverse plane. The following secondary image reconstructions were conducted for each patient: a two dimensional (2D) multiplanar reconstruction (MPR), maximum intensity projection (MIP), and 3D volume rendering (VR). Post-injury lesions of the facial skeleton were assessed and the presence of any loose displaced bone fragments was taken into consideration. Results: As far as fracture imaging is concerned, the 2D image reconstruction and volume rendering proved to be the most effective in the majority of locations. 3D image reconstructions proved the most sensitive in most cases of loose displaced bone fragments, except for fine structures such as the ethmoid bone and the inferior orbital wall. Conclusions: 1. Multiplanar computer reconstructions increase the effectiveness of visualisation of

Indications for direct multidirectional or multiplanar electronic reconstructions in CT-scanning of the head

International Nuclear Information System (INIS)

Kaiser, M.C.; Veiga-Pires, J.A.; Gooskens, R.; Troost, J.

1982-01-01

The authors set out to indicate the optimal applications at minimum radiation penalty of both direct multidirectional and multiplanar electronic reconstruction modes in CT-scanning of the head by means of two illustrative case reports of midline congenital tumours. (orig.)

Low-dose computed tomographic imaging in orbital trauma

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Jackson, A.; Whitehouse, R.W. (Manchester Univ. (United Kingdom). Dept. of Diagnostic Radiology)

1993-08-01

The authors review findings in 75 computed tomographic (CT) examinations of 66 patients with orbital trauma who were imaged using a low-radiation-dose CT technique. Imaging was performed using a dynamic scan mode and exposure factors of 120 kVp and 80 mAs resulting in a skin dose of 11 mGy with an effective dose-equivalent of 0.22 mSv. Image quality was diagnostic in all cases and excellent in 73 examinations. Soft-tissue abnormalities within the orbit including muscle adhesions were well demonstrated both on primary axial and reconstructed multiplanar images. The benefits of multiplanar reconstructions are stressed and the contribution of soft-tissue injuries to symptomatic diplopia examined. (author).

Reconstruction of a ring applicator using CT imaging: impact of the reconstruction method and applicator orientation

International Nuclear Information System (INIS)

Hellebust, Taran Paulsen; Tanderup, Kari; Bergstrand, Eva Stabell; Knutsen, Bjoern Helge; Roeislien, Jo; Olsen, Dag Rune

2007-01-01

The purpose of this study is to investigate whether the method of applicator reconstruction and/or the applicator orientation influence the dose calculation to points around the applicator for brachytherapy of cervical cancer with CT-based treatment planning. A phantom, containing a fixed ring applicator set and six lead pellets representing dose points, was used. The phantom was CT scanned with the ring applicator at four different angles related to the image plane. In each scan the applicator was reconstructed by three methods: (1) direct reconstruction in each image (DR) (2) reconstruction in multiplanar reconstructed images (MPR) and (3) library plans, using pre-defined applicator geometry (LIB). The doses to the lead pellets were calculated. The relative standard deviation (SD) for all reconstruction methods was less than 3.7% in the dose points. The relative SD for the LIB method was significantly lower (p < 0.05) than for the DR and MPR methods for all but two points. All applicator orientations had similar dose calculation reproducibility. Using library plans for applicator reconstruction gives the most reproducible dose calculation. However, with restrictive guidelines for applicator reconstruction the uncertainties for all methods are low compared to other factors influencing the accuracy of brachytherapy

Potential contribution of multiplanar reconstruction (MPR) to computer-aided detection of lung nodules on MDCT

International Nuclear Information System (INIS)

Matsumoto, Sumiaki; Ohno, Yoshiharu; Yamagata, Hitoshi; Nogami, Munenobu; Kono, Atsushi; Sugimura, Kazuro

2012-01-01

Purpose: To evaluate potential benefits of using multiplanar reconstruction (MPR) in computer-aided detection (CAD) of lung nodules on multidetector computed tomography (MDCT). Materials and methods: MDCT datasets of 60 patients with suspected lung nodules were retrospectively collected. Using “second-read” CAD, two radiologists (Readers 1 and 2) independently interpreted these datasets for the detection of non-calcified nodules (≥4 mm) with concomitant confidence rating. They did this task twice, first without MPR (using only axial images), and then 4 weeks later with MPR (using also coronal and sagittal MPR images), where the total reading time per dataset, including the time taken to assess the detection results of CAD software (CAD assessment time), was recorded. The total reading time and CAD assessment time without MPR and those with MPR were statistically compared for each reader. The radiologists’ performance for detecting nodules without MPR and the performance with MPR were compared using jackknife free-response receiver operating characteristic (JAFROC) analysis. Results: Compared to the CAD assessment time without MPR (mean, 69 s and 57 s for Readers 1 and 2), the CAD assessment time with MPR (mean, 46 s and 45 s for Readers 1 and 2) was significantly reduced (P < 0.001). For Reader 1, the total reading time was also significantly shorter in the case with MPR. There was no significant difference between the detection performances without MPR and with MPR. Conclusion: The use of MPR has the potential to improve the workflow in CAD of lung nodules on MDCT.

Imaging of the vagina and vulva

International Nuclear Information System (INIS)

Souza, Luis Ronan Marquez Ferreira de; Szejnfeld, Jacob; Signorini Filho, Roney Cesar; Marques, Renato Moretti; Nicolau, Sergio Mancini; Goldman, Suzan Menasce

2006-01-01

In gynecological daily practices, the vulva and vagina are examined during physical examination, however there are situations where this is not possible or it is needed to determine the extension of an injury through imaging methods. The magnetic resonance imaging is an excellent cross-sectional modality for evaluation the alterations of vulva and vagina due its multiplanar evaluation and high tecidual contrast. Other cross-sectional modalities are ultrasound and enhanced computed tomography. This paper intends to give an overview of vaginal and vulvar pathology that can be identified by the radiologist. (author)

Usefulness of multidetector-row CT (MDCT) for the diagnosis of non-occlusive mesenteric ischemia (NOMI): Assessment of morphology and diameter of the superior mesenteric artery (SMA) on multi-planar reconstructed (MPR) images

International Nuclear Information System (INIS)

Woodhams, Reiko; Nishimaki, Hiroshi; Fujii, Kaoru; Kakita, Satoko; Hayakawa, Kazushige

2010-01-01

Objective: The purpose of this study was to assess the efficacy of multidetector-row CT (MDCT) for the diagnosis of non-occlusive mesenteric ischemia (NOMI) by analyzing morphology and diameter of superior mesenteric artery (SMA). We assessed whether MDCT was as useful as angiography for the diagnosis of NOMI. Materials and methods: Four patients who were diagnosed with NOMI were retrospectively analyzed. All patients had 8-row MDCT followed by laparotomy. Two of them underwent angiography after MDCT. The morphology and diameter of SMA of these cases was analyzed on multi-planar reconstructed (MPR) images. The mean diameter of SMA of NOMI cases was compared to that of 13 control cases. Results: MPR images of all NOMI cases showed irregular narrowing of the SMA, spasm of the arcades of SMA, and poor demonstration of intramural vessels. MPR images of two patients who had angiography were concordant with their angiograms. The mean diameter of SMA of NOMI patients was 3.4 ± 1.1 mm, which was statistically smaller than that of 13 control patients, 6.0 ± 1.5 mm (P < 0.05, Wilcoxon rank sum tests). Conclusion: Angiography has been recognized essential for the diagnosis of NOMI. This study shows the possibility of MDCT to be an equivalently useful modality compared to angiography for the diagnosis of NOMI by interpreting morphologic appearance and diameter of SMA. Introduction of MDCT in the decision tree of NOMI treatment may bring the benefit of prompt diagnosis and subsequent early and efficient initiation of therapy, which may improve the mortality.

Advantages of digital imaging for radiological diagnostic

International Nuclear Information System (INIS)

Trapero, M. A.; Gonzalez, S.; Albillos, J. C.; Martel, J.; Rebollo, M.

2006-01-01

The advantages and limitations of radiological digital images in comparison with analogic ones are analyzed. We discuss three main topics: acquisition, post-procedure manipulation, and visualization, archive and communication. Digital acquisition with computed radiology systems present a global sensitivity very close to conventional film for diagnostic purposes. However, flat panel digital systems seems to achieve some advantages in particular clinical situations. A critical issue is the radiation dose-reduction that can be accomplished without reducing image quality nor diagnostic exactitude. The post-procedure manipulation allows, particularly in multiplanar modalities like CT or MR, to extract all implicit diagnostic information in the images: Main procedures are multiplanar and three-dimensional reformations, dynamic acquisitions, functional studies and image fusion. The use of PACS for visualization, archive and communication of images, improves the effectiveness and the efficiency of the workflow, allows a more comfortable diagnosis for the radiologist and gives way to improvements in the communication of images, allowing tele consulting and the tele radiology. (Author) 6 refs

Post-processing of digital images.

Science.gov (United States)

Perrone, Luca; Politi, Marco; Foschi, Raffaella; Masini, Valentina; Reale, Francesca; Costantini, Alessandro Maria; Marano, Pasquale

2003-01-01

Post-processing of bi- and three-dimensional images plays a major role for clinicians and surgeons in both diagnosis and therapy. The new spiral (single and multislice) CT and MRI machines have allowed better quality of images. With the associated development of hardware and software, post-processing has become indispensable in many radiologic applications in order to address precise clinical questions. In particular, in CT the acquisition technique is fundamental and should be targeted and optimized to obtain good image reconstruction. Multiplanar reconstructions ensure simple, immediate display of sections along different planes. Three-dimensional reconstructions include numerous procedures: multiplanar techniques as maximum intensity projections (MIP); surface rendering techniques as the Shaded Surface Display (SSD); volume techniques as the Volume Rendering Technique; techniques of virtual endoscopy. In surgery computer-aided techniques as the neuronavigator, which with information provided by neuroimaging helps the neurosurgeon in simulating and performing the operation, are extremely interesting.

Magnetic resonance imaging in neuroradiology

International Nuclear Information System (INIS)

Voigt, K.; Lotx, J.W.

1990-01-01

Magnetic resonance imaging (MRI) is now accepted as an effective method of investigating a wide range of disorders, especially of the brain and spine. A short introduction on image contrast in MRI is given and the advantages and disadvantages for the different diseases of the brain is discussed. Excellent soft-tissue contrast, multiplanar imaging capabilities and lack of ionising radiation are conspicuous advantages, and it is now established as the investigation of choice in a large number of clinical conditions, especially when the central nervous system is involved. However, it remains only one of a series of imaging modalities. A confident provisional clinical diagnosis is essential for establishing an imaging protocol and the intention should always be to reach a definitive diagnosis in the least invasive and most cost-effective way. 7 figs., 19 refs

Bone grafting via reamer-irrigator-aspirator for nonunion of open Gustilo-Anderson type III tibial fractures treated with multiplanar external fixator

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Kusnezov Nicholas

2017-01-01

Full Text Available Introduction: The purpose of this investigation was to evaluate the outcomes following reamer-irrigator-aspirator (RIA autogenous bone grafting (ABG of high-grade open tibia fracture nonunions stabilized via multiplanar external fixation. Methods: We retrospectively reviewed all patients with Gustilo-Anderson type III open tibia fractures treated with multiplanar external fixation and who underwent RIA ABG for nonunion at our institutional Level 1 Trauma Center between 2008 and 2015. All patients between 15 and 65 years of age with a minimum of six-month follow-up were included. The primary outcomes of interest were achievement of union, time to union, and incidence of revision surgery. Complications and all-cause reoperation were recorded as secondary endpoints. Results: Fifteen patients met the inclusion criteria with a mean age of 41.1 ± 14.0 years. RIA ABG was harvested from the femur in all cases, with a mean volume of 34 ± 15 mL. At an average follow-up of 13.3 ± 6.8 months, all patients achieved union, including two who required repeat RIA ABG. One patient experienced a femoral shaft fracture four months following RIA that required intramedullary fixation. The average time to union was 6.0 ± 6.3 months. Twelve patients (80% went on to union within six months and 13 (86.7% within one year. Five patients experienced a total of six post-operative complications including three deep infections, one refracture through the nonunion site, and one gradual varus deformity. Two patients in this series required a subsequent RIA autografting procedure secondary to persistent nonunion despite initial RIA. Conclusion: We found that RIA ABG offered a reliable solution to nonunion of Gustilo-Anderson type III open tibial fractures treated with multiplanar external fixation, circumventing the need to change the method of fixation.

Need for three-dimensional imaging in postsurgical ''falled back'' syndrome

International Nuclear Information System (INIS)

Zinreich, S.J.; Wang, H.; Long, D.M.; Quinn, C.M.; Rosenbaum, A.E.

1987-01-01

One hundred ten patients with persistent symptoms after low back surgery were examined with direct axial CT, 2D multiplanar, and 3D imaging. Sixty-three of these patients had lumbar spinal fusion. The 3D images were found to best display the integrity of fusion (assessed by continuity, pseudoarthrosis, incomplete fusion, transitional syndrome) in 44 of the 63 patients (65%). In 55 of the 110 patients lateral spinal stenosis was found; in 43% (24 of 55) this was uncovered on the 3D images. 3D also better showed the extent and type of surgery performed in 23% (26 of 110). Furthermore, 15 pars interarticularis, four facet fractures, and eight spinal malalignments were perceived only on 3D. 3D image afforded additional information over the direct axial and multiplanar reconstruction techniques in 63 of 110 patients

MR imaging of articular cartilage : comparison of magnetization transfer contrast and fat-suppression in multiplanar and 3D gradient-echo, spin-echo, turbo spin-echo techniques

International Nuclear Information System (INIS)

Lee, Young Joon; Joo, Eun Young; Eun, Choong Ki

1999-01-01

The purpose of this study was to evaluate the effects of magnetization transfer contrast(MTC) and fat-suppression(FS) in variable spin-echo and gradient-echo sequences for articular cartilage imaging and to determine the optimal pulse sequences. Using variable 7-pulse sequences, the knees of 15 pigs were imaged Axial images were obtained using proton density and T2-weighted spin-echo (PDWSE and T2WSE), turbo spin-echo (TSE), multiplanar gradient-echo (MPGR), and 3D steady-state gradient-echo (3DGRE) sequences, and the same pulse sequences were then repeated using MTC. Also T1-weighted spin-echo(T1WSE) and 3D spoiled gradient-echo(3DSPGR) images of knees were also acquired, and the procedure was repeated using FS. For each knee, a total of 14 axial images were acquired, and using a 6-band scoring system, the visibility of and the visibilities of the the articular cartilage was analyzed. The visual effect of MTC and FS was scored using a 4-band scale. For each image, the signal intensities of articular cartilage, subchondral bone, muscles, and saline were measured, and signal-to-noise ratios(SNR) and contrast-to-noise ratios(CNR) were also calculated. Visibility of the cartilage was best when 3DSPGR and T1WSE sequences were used. MTC imaging increased the negative contrast between cartilage and saline, but FS imaging provided more positive contrast. CNR between cartilage and saline was highest when using TSE with FS(-351.1±15.3), though CNR between cartilage and bone then fell to -14.7±10.8. In MTC imaging using MPGR showed the greatest increase of negative contrast between cartilage and saline(CNR change=-74.7); the next highest was when 3DGRE was used(CNR change=-34.3). CNR between cartilage and bone was highest with MPGR(161.9±17.7), but with MTC, the greatest CNR decrease(-81.8) was observed. The greatest CNR increase between cartilage and bone was noted in T1WSE with FS. In all scans, FS provided a cartilage-only positive contrast image, though the absolute

CT-based virtual tracheobronchoscopy in children - comparison with axial CT and multiplanar reconstruction: preliminary results

International Nuclear Information System (INIS)

Sorantin, Erich; Lindbichler, Franz; Eber, Ernst; Schimpl, Guenther

2002-01-01

Background: 3D post-processing of spiral-CT (S-CT) data using perspective projection allows the generation of virtual views similar to endoscopy. Objective: To evaluate whether simultaneous reading of axial S-CT, multiplanar reconstruction (MPR) and virtual tracheobronchoscopy (VTB) is more precise and accurate than reading of axial S-CT and MPR alone in paediatric patients. Materials and methods: S-CT studies of 15 symptomatic and 4 normal patients were investigated. Two radiologists independently read two sets of images for airway abnormalities: first axial CT and MPR, followed by axial CT, MPR and VTB. A final decision was later made by consensus. All results were compared to fibre-optic bronchoscopy (FTB). Interobserver agreement was used as an indicator of precision for the display technique used. Results: At reading of axial S-CT and MPR an interobserver agreement of 89.5% (κ=0.776, P<0.00103) was found. Based on the consensus decision, a diagnostic accuracy of 89.5% at a sensitivity 86.6% and specificity of 100% (κ=0.776, 95% CI 0.491-1.062, P<0.00103) was achieved. At reporting on axial S-CT, MPR and VTB, all cases were classified correctly by both readers, indicating 100% accuracy, interobserver agreement, sensitivity and specificity (κ=1.00, 95% CI 1.0-1.0, P<0.000258). Conclusions: The simultaneous display of axial S-CT, MPR and VTB raises the precision, accuracy and sensitivity of radiological reports. (orig.)

Diagnostic imaging in undergraduate medical education: an expanding role

International Nuclear Information System (INIS)

Miles, K.A.

2005-01-01

Radiologists have been involved in anatomy instruction for medical students for decades. However, recent technical advances in radiology, such as multiplanar imaging, 'virtual endoscopy', functional and molecular imaging, and spectroscopy, offer new ways in which to use imaging for teaching basic sciences to medical students. The broad dissemination of picture archiving and communications systems is making such images readily available to medical schools, providing new opportunities for the incorporation of diagnostic imaging into the undergraduate medical curriculum. Current reforms in the medical curriculum and the establishment of new medical schools in the UK further underline the prospects for an expanding role for imaging in medical education. This article reviews the methods by which diagnostic imaging can be used to support the learning of anatomy and other basic sciences

The diagnostic value of multiplanar reconstruction on MDCT colonography for the preoperative staging of colorectal cancer

International Nuclear Information System (INIS)

Jin, Kwang Nam; Kim, Se Hyung; Lee, Jae Young; Lee, Jeong Min; Han, Joon Koo; Choi, Byung Ihn; Shin, Kyung-Sook

2006-01-01

The purpose of this study was to determine whether multiplanar reconstruction (MPR) images can improve the accuracy of MDCT-based colorectal cancer preoperative staging by receiver-operating characteristic (ROC) analysis. Fifty-five patients with colorectal cancer underwent contrast-enhanced CT colonography using an 8- or 16-row scanner. Two separate interval reviews of the axial MDCT datasets with/without MPR images (coronal and sagittal) were performed independently by two radiologists blinded to both the colonoscopic and histopathologic results. At each review session, the radiologists were asked to determine the colorectal cancer TNM stage within the context of differentiating ≤T3 from T4, N0 from ≥N1 and M0 from M1 using a five-point confidence scale. The radiologists' performance for staging the colorectal cancer using axial CT datasets with/without MPR images was evaluated using ROC analysis. Sensitivities, specificities and interobserver agreement were assessed. When MPR images were added, significant improvement was achieved by both radiologists for differentiating N0 from ≥N1 in terms of both A Z (0.651 to 0.769; 0.573 to 0.713) and specificity (26.7 to 69.2%; 23.1 to 76.9%) (P 0.05), but a significant improvement in the specificity (70 to 90%; 80 to 92%) was achieved by one radiologist (P<0.05). In terms of the M staging, a significant improvement in the Az (0.844 to 0.996) was observed for the combined interpretation of the axial and MPR images by one radiologist (P<0.05). Furthermore, substantial or almost perfect interobserver agreement was achieved for all TNM stagings for the combined interpretations (κ=0.641-0.866), whereas only fair to substantial agreement was achieved for the axial images alone (κ=0.337-0.707). In conclusion, the combined interpretation of the axial and MPR MDCT images significantly improved the local staging of colorectal cancer compared with assessments based on axial images alone. (orig.)

Diagnostic value of multiplanar reconstruction in CT recognition of lumbar spinal disorders

International Nuclear Information System (INIS)

Im, S. K.; Choi, J. H.; Kim, C. H.; Sohn, M. H.; Lim, K. Y.; Choi, K. C.

1984-01-01

The computer tomography is useful in evaluation of bony structures and adjacent soft tissues of the lumbar spine. Recently, the multiplanar reconstruction of lumbar spine of CT of significant value for the anatomical localization and for the myelographic and surgical correlation. We observed 177 cases of lumbar spine CT, who complains of spinal symptom, during the period from Dec. 1982 to Aug. 1984. The results were as follows: 1. The sex distribution of cases were 113 males and 44 females. The CT diagnosis showed 152 cases of herniated lumbar disc, 15 cases of degenerative disease, 5 cases of spine tbc., 3 cases of spine trauma and 2 cases of meningocele. 2. CT findings of herniated disc were as follows: focal protrusion of posterior disc margin and obliteration of anterior epidural fat in all cases, indentation on dural sac in 92 cases (60.5%) soft tissue mass in epidural fat in 85 cases (55.9%), compression or displacement of nerve root sheath in 22 cases(14.4%). 3. Sites of herniated lumbar disc were at L4-L5 level in 100 cases(59.1%) and at L5-S1 level in 65 cases (38.4%). Location of it were central type in 70 cases(41.1%), left-central type in 46 cases (27.2%), right-central type in 44 cases(26.0%) and lateral type in 9 cases (5.1%). 4. The sagittal reconstruction images were helpful in evaluating neural foramina, size of disc bluge into spinal canal, especially at L5-S1, and patients with spondylolisthesis. The coronal reconstruction images were the least informative, although they contributed to the evaluation of lumbar nerve roots of course, the axial CT scans were the most sensitive and specific.

MR imaging of invasive carcinoma of the uterine cervix

International Nuclear Information System (INIS)

Lien, H.H.

1999-01-01

MR imaging is noninvasive and provides direct multiplanar images with good contrast between different soft tissues. It has a potential in distinguishing normal from abnormal tissue and is a valuable technique in examination of the female pelvis. This report reviews the present role of MR imaging in the initial work-up of patients with carcinoma of the uterine cervix. (orig./AJ)

The value of multislice helical CT in the diagnosis of the rib micro-fracture

International Nuclear Information System (INIS)

Wang Shuli; Wang Linsen; Sun Dingyuan; Deng Xin; Geng Xin; Li Jian; Liu Zhigang; Guo Lin; Jia Zhihong

2005-01-01

Objective: To evaluate the clinical value of MSCT with thin-section reconstruction and curved multiplanar reformation of rib micro-fracture. Methods: Thirty-eight patients suspected ribs fracture by clinical examination, which had negative appearance in X-ray film, were performed with MSCT scan with thin-section reconstructed and curved multiplanar reformation. The imaging of 5 mm, 1 mm thickness and curved reformatted imags were analysed by three groups of radiologists respectively. Results: Of the 38 patients, 26 patients were demonstrated ribs fracture with 1 mm thin-section reconstructed and curved multiplanar reformatted CT imaging, which were classified as complete fracture in 18 ribs and incomplete fracture in 41 ribs. The ends of the fractures displacement located within a distance of double-thickness of the cortex of the complete ribs fracture. With 5 mm thickness imaging, the accuracy of the diagnosis was 86.4%, 89.8% and 94.9% by three groups radiologists, respectively. Conclusion: The rib fracture is very common in clinic, the incomplete and non evident displacement complete ribs fracture are difficult to be diagnosed by plain radiography. The MSCT can produce a large range volume information scan. Thin-section reconstructed and curved multiplanar reformatted imaging should be the effective method in diagnosis of ribs fracture. The total rib pattern and location, extend of all the ribs fracture in this cases can be displayed in one scan by the curved multiplanar reformatted imaging. (authors)

Uterine cervical carcinoma: a comparison of two- and three-dimensional T2-weighted turbo spin-echo MR imaging at 3.0 T for image quality and local-regional staging

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Shin, Y.R. [The Catholic University of Korea, Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, 222, Banpo-daero, Seocho-gu, Seoul (Korea, Republic of); The Catholic University of Korea, Department of Radiology, Incheon St. Mary' s Hospital, College of Medicine, Bupyeong 6-dong, Bupyeong-gu, Incheon (Korea, Republic of); Rha, S.E.; Choi, B.G.; Oh, S.N.; Park, M.Y.; Byun, J.Y. [The Catholic University of Korea, Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, 222, Banpo-daero, Seocho-gu, Seoul (Korea, Republic of)

2013-04-15

To compare three-dimensional (3D) T2-weighted turbo spin-echo (TSE) with multiplanar two-dimensional (2D) T2-weighted TSE for the evaluation of invasive cervical carcinoma. Seventy-five patients with cervical carcinoma underwent MRI of the pelvis at 3.0 T, using both 5-mm-thick multiplanar 2D (total acquisition time = 12 min 25 s) and 1-mm-thick coronal 3D T2-weighted TSE sequences (7 min 20 s). Quantitative analysis of signal-to-noise ratio (SNR) and qualitative analysis of image quality were performed. Local-regional staging was performed in 45 patients who underwent radical hysterectomy. The estimated SNR of cervical carcinoma and the relative tumour contrast were significantly higher on 3D imaging (P < 0.0001). Tumour conspicuity was better with the 3D sequence, but the sharpness of tumour margin was better with the 2D sequence. No significant difference in overall image quality was noted between the two sequences (P = 0.38). There were no significant differences in terms of the diagnostic accuracy, sensitivity, and specificity of parametrial invasion, vaginal invasion, and lymph node metastases. Multiplanar reconstruction 3D T2-weighted imaging is largely equivalent to 2D T2-weighted imaging for overall image quality and staging accuracy of cervical carcinoma with a shorter MR data acquisition, but has limitations with regard to the sharpness of the tumour margin. circle 3D T2-weighted MR sequence is equivalent to 2D for cervical carcinoma staging. (orig.)

Imaging of spine injuries

International Nuclear Information System (INIS)

Lomoschitz, F. . e-mai: friedrich.lomoschitz@univie.ac.at

2001-01-01

Spinal trauma requires a prompt and detailed diagnosis for estimating the prognosis and installing proper therapy. Conventional radiograms are the first imaging modality in most cases. In the cervical and the lumbar spine, a CT has to be performed in patients with polytrauma and a higher risk of complications or with signs of instability. Especially for imaging the cervicocranium, multiplanar reformations in sagittal and coronal planes are necessary. For fractures of the thoracic spine, MR imaging is superior to CT because of the better detection of associated neurologic complications. (author)

Postoperative imaging of paranasal sinuses

International Nuclear Information System (INIS)

Nemec, S.; Czerny, C.; Formanek, M.

2007-01-01

The radiological interpretation of postoperative changes of the paranasal sinuses requires knowledge of why and how the surgical intervention was performed and what the basic clinical findings were. It is important to know whether there was an inflammation, a reconstructive procedure, or a tumorous process. Multidetector computed tomography (MDCT) evaluated in a high-resolution bone window level setting represents the method of choice for imaging after nonfunctional and functional procedures after inflammatory changes as well as for imaging after reconstructive surgery because of facial trauma or before dental implantation. In the postoperative follow-up of tumor patients contrast-enhanced MDCT evaluated in a soft tissue window and bone window and especially magnetic resonance imaging (MRI) represent the standard. In many cases it is possible to differentiate tumor recurrence from inflammation with the help of contrast-enhanced multiplanar MRI and to detect bone marrow changes prior to CT. (orig.)

MR imaging of the pediatric central nervous system utilization review

International Nuclear Information System (INIS)

Barnes, P.D.; Prince, J.R.; Galloway, D.C.; Ross-Duggan, J.; Lester, P.D.; Yamanashi, W.S.

1986-01-01

MR has been done in over 500 pediatric and adolescent patients (ages 5 days to 20 years) with central nervous system (CNS) disease (brain, n = 331; spine, n = 218), including high-field and special coil application in 362 cases. T1-weighted, multiplanar MR imaging provides superior anatomic delineation of organogenetic CNS malformations, while multiparameter (T1, T2, p) MR is usually necessary for more complete characterization of histogenetic malformations, as well as acquired conditions. MR imaging is a desirable method for the initial and definitive evaluation of many cranial and spinal conditions of childhood (more-invasive procedures were obviated in 164 patients). CT or other modalities may be added when MR imaging does not satisfy the clinical query

- LAA Occluder View for post-implantation Evaluation (LOVE) - standardized imaging proposal evaluating implanted left atrial appendage occlusion devices by cardiac computed tomography

International Nuclear Information System (INIS)

Behnes, Michael; Akin, Ibrahim; Sartorius, Benjamin; Fastner, Christian; El-Battrawy, Ibrahim; Borggrefe, Martin; Haubenreisser, Holger; Meyer, Mathias; Schoenberg, Stefan O.; Henzler, Thomas

2016-01-01

A standardized imaging proposal evaluating implanted left atrial appendage (LAA) occlusion devices by cardiac computed tomography angiography (cCTA) has never been investigated. cCTA datasets were acquired on a 3 rd generation dual-source CT system and reconstructed with a slice thickness of 0.5 mm. An interdisciplinary evaluation was performed by two interventional cardiologists and one radiologist on a 3D multi-planar workstation. A standardized multi-planar reconstruction algorithm was developed in order to assess relevant clinical aspects of implanted LAA occlusion devices being outlined within a pictorial essay. The following clinical aspects of implanted LAA occlusion devices were evaluated within the most appropriate cCTA multi-planar reconstruction: (1) topography to neighboring structures, (2) peri-device leaks, (3) coverage of LAA lobes, (4) indirect signs of neo-endothelialization. These are illustrated within concise CT imaging examples emphasizing the potential value of the proposed cCTA imaging algorithm: Starting from anatomical cCTA planes and stepwise angulation planes perpendicular to the base of the LAA devices generates an optimal LAA Occluder View for post-implantation Evaluation (LOVE). Aligned true axial, sagittal and coronal LOVE planes offer a standardized and detailed evaluation of LAA occlusion devices after percutaneous implantation. This pictorial essay presents a standardized imaging proposal by cCTA using multi-planar reconstructions that enables systematical follow-up and comparison of patients after LAA occlusion device implantation. The online version of this article (doi:10.1186/s12880-016-0127-y) contains supplementary material, which is available to authorized users

Multiplanar transesophageal echocardiography for the evaluation and percutaneous management of ostium secundum atrial septal defects in the adult.

Science.gov (United States)

Sobrino, Ayax; Basmadjian, Arsène J; Ducharme, Anique; Ibrahim, Reda; Mercier, Lise-Andrée; Pelletier, Guy B; Marcotte, François; Garceau, Patrick; Burelle, Denis; O'Meara, Eileen; Dore, Annie

2012-01-01

The purpose of this paper is to review the usefulness of multiplanar transesophageal echocardiography before, during and after percutaneous transcatheter closure of secundum atrial septal defects. Transesophageal echocardiography imaging techniques,including their role in patient selection, procedural guidance and immediate assessment of technical success and complications are described and discussed in this review. Percutaneous transcatheter closure is indicated for ostium secundum atrial septal defects of less than 40 mm in maximal diameter. The defect must have a favorable anatomy, with adequate rims of at least 5 mm to anchor the prosthesis. Transesophageal echocardiography plays a critical role before the procedure in identifying potential candidates for percutaneous closure and to exclude those with unfavorable anatomy or associated lesions, which could not be addressed percutaneously. Transesophageal echocardiography is also important during the procedure to guide the deployment of the device. After device deployment, the echocardiographer must assess the device (integrity, position and stability), residual shunt, atrio-ventricular valve regurgitation, obstruction to systemic or venous return and pericardial effusion, in order to determine procedural success and diagnose immediate complications.

The contribution of high-resolution multiplanar reformats of the skull base to the detection of skull-base fractures

International Nuclear Information System (INIS)

Connor, S.E.J.; Flis, C.

2005-01-01

AIM: To investigate the contribution of routine review of submillimetric multiplanar reformats to the diagnosis of skull-base fractures. METHODS: A prospective analysis was performed of 407 cases referred over a 6-month period for CT of the skull following cranial trauma. The reformatted 5-mm axial sections and subsequently the high-resolution multiplanar reformats (HRMPRs) were viewed on an ADW 4.1 workstation using bone windows and algorithm. All skull-base fractures and related features, recorded by the consensus of two radiologists, were classified as anatomically significant or non-significant on the basis of eight criteria. The clinical features of skull-base injury and any subsequent treatment were noted in all cases of skull-base fracture. RESULTS: HRMPRs detected 80 separate skull-base fractures in 36/407 cases. Of these 80 fractures, 57 were visible on 5-mm axial sections. In 8 of the 36 cases, the significant anatomical features were only evident on review of the HRMPRs. In 6 of the 36 cases, none of the skull-base fractures was visible on 5-mm sections, but these individuals had only minor associated clinical features and no therapeutic requirements. Review of HRMPRs could have been confined to patients with skull-base fractures, abnormal intracranial and extracranial air collections or opacified mastoid air cells revealed by 5-mm axial sections. This policy would have led to the detection of 79/80 (99%) of skull-base fractures and all significant anatomical features. CONCLUSION: The 5-mm axial sections demonstrated 71% of skull-base fractures and 78% of skull-base fractures with significant anatomical features, using HRMPRs as a gold standard. There were no significant clinical sequelae at short-term follow-up of those fractures only evident on HRMPRs

Advanced imaging of the musculoskeletal system: Standard, three-dimensional, and contrast-enhanced CT and MR imaging, and quantitative bone densitometry

International Nuclear Information System (INIS)

Resnick, D.; Sartoris, D.J.

1987-01-01

This course reviews the application of advanced imaging techniques to a broad spectrum of musculoskeletal disorders. The indications for and utility of standard CT in both the axial and the appendicular skeleton is explored. The combined use of CT with air and contrast arthrography at sites including the hip, knee, and shoulder is discussed. A summary of the proved and potential applications of MR imaging in osseous, articular, bone marrow, and soft-tissue disorders is provided. The utility of intraarticular contrast agents in enhancing the diagnostic capabilities of MR imaging for disorders of hyaline cartilage and and fibrocartilage is demonstrated. The advantages of multiplanar reformation and three-dimensional image reconstruction of cross-sectional imaging data are described in conjunction with the fundamental technological principles of these strategies. Accepted methods as well as investigative techniques for the diagnosis and follow-up of metabolic bone disease are contrasted with regard to relative indications, advantages, and limitations

3D MRI of the colon: methods and first results of 5 patients

International Nuclear Information System (INIS)

Luboldt, W.; Bauerfeind, P.; Pelkonen, P.; Steiner, P.; Krestin, G.P.; Debatin, J.F.

1997-01-01

Purpose: 'Exoscopic' and endoscopic identification of colorectal pathologies via MRI. Methods: 5 patients (36-88 years), two normal and three with different colorectal pathologies (diverticular disease, polyps and carcinoma of the colon), were examined by MRI after colonoscopy. Subsequent to filling of the colon with a gadolinium-water mixture under MRI-monitoring, 3D-data sets of the colon were acquired in prone and supine positions over a 28 sec breathold interval. Subsequently multiplanar T 1 -weighted 2D-sequences were acquired before and following i.v. administration of Gd-DTPA (0.1 mmol/kg BW). All imaging was performed in the coronal orientation. The 3D-data were interactively analysed based on various displays: Maximum intensity projection (MIP), surface shadowed display (SSD), multiplanar reconstruction (MPR), virtual colonoscopy (VC). Results: All of the colorectal pathologies could be interactively diagnosed by MPR. On MIP images some pathologies were missed. VC presented the morphology of colon haustra as well as of all endoluminally growing lesions in a manner similar to endoscopy. The colon masses showed uptake of contrast media and could thus be differentiated from air or faeces. (orig./AJ) [de

MR imaging of neuronal migration anomaly

International Nuclear Information System (INIS)

Hong, Hyun Sook; Choi, Eun Wan; Kim, Dae Ho; Chung, Moo Chan; Kwon, Kuy Hyang; Kim, Ki Jung

1991-01-01

Abnormalities of neuronal migration are characterized by anectopic location of neurons in the cerebral cortex. This broad group of anomalies includes agyria, pachygyria, schizencephaly, unilateral megalencephaly, and gray matter heterotopia. Patients with this anomaly present clinically with a variety of symptoms which are proportional to the extent of the brain involved. These abnormalities have characterized pathologically in vivo by sonography and CT scan. MR appears to be an imaging technique of choice in evaluating these anomalies because it is capable of exceptionally good differentiation between gray and white matter, high contrast resolution, multiplanar display of the anatomy, and lack of overlying bone artifac. The purpose of this paper is to describe the MR findings of neuronal migration anomaly. The results of our study support that MR appears to be the imaging method of choice for diagnosing migration anomalies and the primary screening method for infants or children who have seisure/and delayed development

Imaging in epilepsy

International Nuclear Information System (INIS)

Gupta, Arun Kumar; Sharma, Raju; Sarma, Dipanka

2000-01-01

Epilepsy is a common problem in the paediatric age group. Imaging plays a vital role in identifying the seizure focus. Cross-sectional imaging modalities like CT and MRI have had a major impact on the management of seizure disorders. MRI, because of its high contrast resolution and multiplanar capability is the ideal imaging modality but its use is restricted due to high cost. Computed tomography is cheaper and is the first, and often, the only modality used, especially in the under privileged areas of the world. In the tropical countries inflammatory granuloma are a common cause of epilepsy and CT is adequate to detect these lesions. Other causes include congenital abnormalities, neoplastic and vascular causes. (author)

The Development of LED-Based Dental Light Using a Multiplanar Reflector Design

Directory of Open Access Journals (Sweden)

Chi-Chang Hsieh

2014-01-01

Full Text Available A multiplanar reflector was designed to enhance the application efficiency of light-emitting diode (LED light sources that can be employed as LED-based dental lights. This study used a high-power LED developed by Nichia, that is, a single LED capable of providing a total luminous flux of 120 lm, as the primarily light source to design and develop an LED-based dental light. This LED complies with the international standards and regulations stipulated in ISO 9680:2007. The light spots produced by the prototype were rectangular, with a length of 200 mm and a width of 100 mm. These light spots achieved maximum illumination of 12,000 lux. The use of LEDs can reduce energy consumption from 50 W to 3 W, providing an energy saving of more than 90%.

Magnetic resonance imaging (MRI) of the renal sinus.

Science.gov (United States)

Krishna, Satheesh; Schieda, Nicola; Flood, Trevor A; Shanbhogue, Alampady Krishna; Ramanathan, Subramaniyan; Siegelman, Evan

2018-04-09

This article presents methods to improve MR imaging approach of disorders of the renal sinus which are relatively uncommon and can be technically challenging. Multi-planar Single-shot T2-weighted (T2W) Fast Spin-Echo sequences are recommended to optimally assess anatomic relations of disease. Multi-planar 3D-T1W Gradient Recalled Echo imaging before and after Gadolinium administration depicts the presence and type of enhancement and relation to arterial, venous, and collecting system structures. To improve urographic phase MRI, concentrated Gadolinium in the collecting systems should be diluted. Diffusion-Weighted Imaging (DWI) should be performed before Gadolinium administration to minimize T2* effects. Renal sinus cysts are common but can occasionally be confused for dilated collecting system or calyceal diverticula, with the latter communicating with the collecting system and filling on urographic phase imaging. Vascular lesions (e.g., aneurysm, fistulas) may mimic cystic (or solid) lesions on non-enhanced MRI but can be suspected by noting similar signal intensity to the blood pool and diagnosis can be confirmed with MR angiogram/venogram. Multilocular cystic nephroma commonly extends to the renal sinus, however, to date are indistinguishable from cystic renal cell carcinoma (RCC). Solid hilar tumors are most commonly RCC and urothelial cell carcinoma (UCC). Hilar RCC are heterogeneous, hypervascular with epicenter in the renal cortex compared to UCC which are centered in the collecting system, homogeneously hypovascular, and show profound restricted diffusion. Diagnosis of renal sinus invasion in RCC is critically important as it is the most common imaging cause of pre-operative under-staging of disease. Fat is a normal component of the renal sinus; however, amount of sinus fat correlates with cardiovascular disease and is also seen in lipomatosis. Fat-containing hilar lesions include lipomas, angiomyolipomas, and less commonly other tumors which engulf sinus

Four-channel multidetector-row computed tomography in the evaluation of facial fractures - optimized parameters for acquisition and multiplanar reformation

International Nuclear Information System (INIS)

Omid, P. M.

2002-08-01

The first part of this thesis is designed to give the reader a comprehensive survey on the complex basic principles of computed tomography (CT), from the early beginning to the recent development of multidetector-row CT (MD-CT). Attention is focused on imaging of trauma in general and on imaging of facial fractures in particular. The second part of this thesis describes a clinical study performed to optimize acquisition protocols and multiplanar reformation (MPR) algorithms for the evaluation of facial fractures using MD-CT, which has not been yet described in literature. For this study, a cadaver head with artificial blunt facial trauma was examined using a 4-channel MD-CT scanner. The influence of acquisition parameters (collimation: 2x0.5 mm/4x1 mm/4x2.5 mm; tube current: 120 mAs/90 mAs/60 mAs), image reconstruction algorithms (standard vs. ultra-high resolution (UHR) modes; reconstructed slice thicknesses: 0.5 mm/1 mm/3 mm; increment: 0.3 mm/0.6 mm/1.5 mm), and reformation algorithms (slice thicknesses: 0.5 mm/1 mm/3 mm; overlap: 0.5 mm/1 mm/3 mm) on detectability of facial fractures in MPRs with MD-CT was analyzed. Effects of algorithms and parameters on image noise, artifacts and delineation of soft tissues were evaluated. The results of this study reliably demonstrate that fracture detection was significantly higher with thin MPRs (0.5/0.5 mm, 1/0.5 mm, 1/1 mm) (p = 0 .014) acquired with 2x0.5 mm collimation (p = 0 .046), in UHR mode (p .0005) with 120 mAs (p = 0 .025). Inter-observer variability showed very good agreement (κ > = 0 .942). Non-UHR mode, lower mAs and thick MPRs (3/0.5 mm, 3/1 mm, 3/0.5 mm) showed significantly decreased detectability. (author)

Three dimensional digital rotational imaging in the evaluation of the fractures

International Nuclear Information System (INIS)

Chong, Se Min; Lee, Min Hee; Kwag, Hyon Joo; Lee, Young Rae; Kook, Shin Ho; Park, Hae Won; Moon, Woo Jin; Kim, Seung Kwon; Chung, Eun Chul

2003-01-01

To evaluate the usefulness and the application of three dimensional digital rotational imaging (3D DRI) by the evaluation of fractures. Sixteen patients with clinically diagnosed or suspicious fracture were involved in this study. The lesion or suspicious sites of all 16 cases were spines (n=7), pelvis (n=3) and so on (n=6; knee elbow, ankle, wrist and foot). In all cases, conventional radiography, multiplanar 2D (slice thickness/pitch=3 or 5 mm/1:1)and volume rendering 3D reconstructed single detector helical CT (HiSpeed Advantage, GE Medical Systems, Milwaukee, WIS) scans and 3D DRI (Integris V-5000, Philips Medical Systems, The Netherlands) with multiplanar intersection and gray scaling as postprocessing technique were performed. 3D DRI was evaluated and compared with conventional radiography, multiplanar 2D CT and volume rendering 3D CT. 3D DRI provided more detail and additional information in 14 cases (88%), comparing with 2D and 3D CT scans. Two fractures were revealed only on 3D DRI other than conventional radiography and CT scans and one case was revealed on 2D CT and 3D DRI. In all cases, we could acquired more detail and additional information from 3D DRI than from 3D CT in the acquisition of 3D imaging. 3D DRI didn't change the classification of fracture in 12 of 13 cases (92%), which revealed the fracture on the conventional radiography or CT. 3D DRI can diagnose and evaluate the fracture rapidly and easily with anatomical and spatial resolution by acquisition of 3D imaging with postprocessing using DRI

Three dimensional digital rotational imaging in the evaluation of the fractures

Energy Technology Data Exchange (ETDEWEB)

Chong, Se Min; Lee, Min Hee; Kwag, Hyon Joo; Lee, Young Rae; Kook, Shin Ho; Park, Hae Won; Moon, Woo Jin; Kim, Seung Kwon; Chung, Eun Chul [School of Medicine, Sungkyunkwan Univ., Seoul (Korea, Republic of)

2003-10-01

To evaluate the usefulness and the application of three dimensional digital rotational imaging (3D DRI) by the evaluation of fractures. Sixteen patients with clinically diagnosed or suspicious fracture were involved in this study. The lesion or suspicious sites of all 16 cases were spines (n=7), pelvis (n=3) and so on (n=6; knee elbow, ankle, wrist and foot). In all cases, conventional radiography, multiplanar 2D (slice thickness/pitch=3 or 5 mm/1:1)and volume rendering 3D reconstructed single detector helical CT (HiSpeed Advantage, GE Medical Systems, Milwaukee, WIS) scans and 3D DRI (Integris V-5000, Philips Medical Systems, The Netherlands) with multiplanar intersection and gray scaling as postprocessing technique were performed. 3D DRI was evaluated and compared with conventional radiography, multiplanar 2D CT and volume rendering 3D CT. 3D DRI provided more detail and additional information in 14 cases (88%), comparing with 2D and 3D CT scans. Two fractures were revealed only on 3D DRI other than conventional radiography and CT scans and one case was revealed on 2D CT and 3D DRI. In all cases, we could acquired more detail and additional information from 3D DRI than from 3D CT in the acquisition of 3D imaging. 3D DRI didn't change the classification of fracture in 12 of 13 cases (92%), which revealed the fracture on the conventional radiography or CT. 3D DRI can diagnose and evaluate the fracture rapidly and easily with anatomical and spatial resolution by acquisition of 3D imaging with postprocessing using DRI.

Measurements of angles of the normal auditory ossicles relative to the reference plane and image reconstruction technique for obtaining optimal sections of the ossicles in high-resolution multiplanar reconstruction using a multislice CT scanner

International Nuclear Information System (INIS)

Fujii, Naoko; Katada, Kazuhiro; Yoshioka, Satoshi; Takeuchi, Kenji; Takasu, Akihiko; Naito, Kensei

2005-01-01

Using high-resolution isotropic volume data obtained by 0.5 mm, 4-row multislice CT, cross-sectional observation of the auditory ossicles is possible from any desired direction without difficulty in high-resolution multiplanar reconstruction (HR-MPR) images, also distortion-free three-dimensional images of the ossicles are generated in three-dimensional CT (3D-CT) images. We measured angles of fifty normal ossicles relative to the reference plane, which has been defined as a plane through the bilateral infraorbital margins to the middle portion of the external auditory canal. Based on the results of angle measurement, four optimal sections of the ossicles for efficient viewing to the ossicular chain were identified. To understand the position of the angle measurement and the four sections, the ossicles and the reference plane were reconstructed in the 3D-CT images. As the result of observation of the ossicles and the reference plane, the malleus was parallel to the incudal long process and perpendicular to the reference plane. As the results of angle measurement, the mean angle of the tympanic portion of the facial nerve relative to the reference plane in the sagittal plane was found to be 17 deg, and the mean angle of the stapedial crura relative to the reference plane in the sagittal plane was found to be 6 deg. The mean angle of the stapes relative to the reference plane in the coronal plane was 44 deg, and the mean angle of the incudal long process relative to the stapes in the coronal plane was 89 deg. In 80% of ears, the stapes extended straight from the incudal long process. Image reconstruction technique for viewing four sections of the ossicles was investigated. Firstly, the image of the malleal head and the incudal short process was identified in the axial plane. Secondly, an image of the malleus along the malleal manubrium was reconstructed in the coronal plane. Thirdly, the image of the incudal long process was seen immediately behind the malletis image

MR imaging in female pelvic organs prolapse

International Nuclear Information System (INIS)

Capiel, Carlos A. h; Bouzas, Carlos A.

2003-01-01

Pelvic floor weakness and consequent organ prolapse may result in a variety of symptoms, including pain, urinary or fecal incontinence and constipation. Diagnosis is made primary on the basis of findings at physical pelvic examination. Imaging is useful in patients in whom findings at physical examination are equivocal. Different imaging techniques (fluoroscopy, ultrasonography), can be useful in evaluating pelvic organs prolapse. MR imaging is a new noninvasive technique that provides a multiplanar global evaluation of the pelvic contents and demonstrates pelvic organs prolapse. Reference points are the pubococcygeal line and puborectalis muscle sling. This pictorial assay illustrates different grades of cystourethrocele, recto-sigmoidocele and hysteroptosis (uterine prolapse) on MR imaging. (author)

Pathologic and post-operative conditions of the plantar fascia: review of MR imaging appearances

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Yu, J.S. [Ohio State Univ., Columbus (United States). Dept. of Radiology

2000-09-01

Magnetic resonance (MR) imaging has emerged as an important noninvasive diagnostic imaging technique for assessment of foot pathology. This modality, owing to its multiplanar imaging capability and inherent superiority in contrast, has been shown to be more accurate and sensitive for detection of plantar fascia pathology than any other imaging method. One of the most important and recognizable causes of heel pain is plantar fasciitis. With the exception of plantar fasciitis, there has been little emphasis on imaging other conditions that affect this important structure. The objective of this review is to demonstrate, from a perspective of MR imaging, the many different pathologic conditions that affect the plantar fascia. Included in this review will be a discussion of normal anatomy as well as entities such as acute plantar fasciitis, chronic plantar fasciitis, traumatic rupture, normal post-surgical changes, pathologic post-fasciotomy conditions, infection, and fibromatosis. (orig.)

Pathologic and post-operative conditions of the plantar fascia: review of MR imaging appearances

International Nuclear Information System (INIS)

Yu, J.S.

2000-01-01

Magnetic resonance (MR) imaging has emerged as an important noninvasive diagnostic imaging technique for assessment of foot pathology. This modality, owing to its multiplanar imaging capability and inherent superiority in contrast, has been shown to be more accurate and sensitive for detection of plantar fascia pathology than any other imaging method. One of the most important and recognizable causes of heel pain is plantar fasciitis. With the exception of plantar fasciitis, there has been little emphasis on imaging other conditions that affect this important structure. The objective of this review is to demonstrate, from a perspective of MR imaging, the many different pathologic conditions that affect the plantar fascia. Included in this review will be a discussion of normal anatomy as well as entities such as acute plantar fasciitis, chronic plantar fasciitis, traumatic rupture, normal post-surgical changes, pathologic post-fasciotomy conditions, infection, and fibromatosis. (orig.)

Usefulness of biological fingerprint in magnetic resonance imaging for patient verification.

Science.gov (United States)

Ueda, Yasuyuki; Morishita, Junji; Kudomi, Shohei; Ueda, Katsuhiko

2016-09-01

The purpose of our study is to investigate the feasibility of automated patient verification using multi-planar reconstruction (MPR) images generated from three-dimensional magnetic resonance (MR) imaging of the brain. Several anatomy-related MPR images generated from three-dimensional fast scout scan of each MR examination were used as biological fingerprint images in this study. The database of this study consisted of 730 temporal pairs of MR examination of the brain. We calculated the correlation value between current and prior biological fingerprint images of the same patient and also all combinations of two images for different patients to evaluate the effectiveness of our method for patient verification. The best performance of our system were as follows: a half-total error rate of 1.59 % with a false acceptance rate of 0.023 % and a false rejection rate of 3.15 %, an equal error rate of 1.37 %, and a rank-one identification rate of 98.6 %. Our method makes it possible to verify the identity of the patient using only some existing medical images without the addition of incidental equipment. Also, our method will contribute to patient misidentification error management caused by human errors.

Sports-related muscle injuries of the lower extremity: MR imaging appearances

International Nuclear Information System (INIS)

Sanchez-Marquez, A.; Gil-Garcia, M.; Valls, C.; Narvaez-Garcia, J.; Andia-Navarro, E.; Pozuelo-Segura, O.; Portabella-Blavia, F.

1999-01-01

Sports-related injuries of the lower extremity are frequent. Before magnetic resonance (MR) imaging was available, ultrasound, radionuclide scintigraphy and computed tomography were used to evaluate muscle trauma. Although relatively inexpensive, these imaging modalities are limited by their low specificity. The high degree of soft tissue contrast and multiplanar capability of MR imaging, allow direct visualization as well as characterization of traumatic muscle lesions. This pictorial review highlights the spectrum of traumatic muscle lesions on MRI, with emphasis on its typical appearances. (orig.)

Image portion identification methods, image parsing methods, image parsing systems, and articles of manufacture

Science.gov (United States)

Lassahn, Gordon D.; Lancaster, Gregory D.; Apel, William A.; Thompson, Vicki S.

2013-01-08

Image portion identification methods, image parsing methods, image parsing systems, and articles of manufacture are described. According to one embodiment, an image portion identification method includes accessing data regarding an image depicting a plurality of biological substrates corresponding to at least one biological sample and indicating presence of at least one biological indicator within the biological sample and, using processing circuitry, automatically identifying a portion of the image depicting one of the biological substrates but not others of the biological substrates.

Imaging by magnetic resonance of pigmented villonodular synovitis

International Nuclear Information System (INIS)

Hernandez Moreno, L.; Lafuente Martinez, J.; Marti Bonmati, L.; Perez Diaz, M.; Vilar Samper, J.; Paniagua, J.C.

1994-01-01

Magnetic resonance (MR) has become the method of choice for evaluating a large number of musculoskeletal disorders, especially because of its capacity to provide multiplanar tomographic sections and its greater contrast resolution as compared to other imaging methods. This report present seven cases of pigmented villonodular synovitis (PVS) located in joints. In six cases, the diagnosis was suggested by MR on the basis of the fact that the lesions showed hypointense areas with no signal in both the T1 and T2-weighted sequences. This is due to hemosiderin deposition in the lesion. In addition to its diagnostic value, in this disorder, MR is an excellent method for assessing the exact extension and location of the lesions, as well as the follow-up to these patients and the detection of possible recurrences. (Author) 17 refs

Myocardial scintigraphy

International Nuclear Information System (INIS)

Bunko, Hisashi; Hisada, Kinichi

1982-01-01

Among the various methods of image diagnosis of the cardiovascular disorder, nuclear cardiology provides noninvasive means for evaluation of myocardial perfusion as well as morphological and functional informations. In this article, clinical application and image diagnosis of myocardial scintigraphy including Tl-201 myocardial perfusion scintigraphy, single photon emission computed tomography with Tl-201, acute myocardial infarction scintigraphy with Tc-99m-pyrophosphate and Ga-67 imaging of the heart, were discussed. Multiplanar imaging of the heart with Tl-201 after stress and at redistribution was the accepted method for detection and evaluation of the ischemic heart disease. Although it achieved high sensitivity and specificity for ischemic heart disease, detection of the small ischemia and quantation of the regional Tl-201 accumulation were difficult with conventional multiplanar imaging. Application of emission computed tomography improved detectability and quantitativity of the ischemia. However, 7-pinhole tomography did not increase the diagnostic accuracy significantly. It had limited clinical applicability due to poor quantitativity in spite of improved image contrast and its tomographic nature. Advantage and limitation of these tomographic imaging and multiplanar imaging were discussed. Problems and prognostic significance of pyrophosphate imaging of the acute myocardial infarction were also discussed. Visualization of the heart with Ga-67 was helpful for identification of the tumor or inflammation of the heart as well as evaluation of the effect of the therapy. (author)

Diagnosis of temporal bone diseases using three-dimensional images with multislice CT

Energy Technology Data Exchange (ETDEWEB)

Toyama, Yoshihiro; Togami, Taro; Murota, Makiko; Fukunaga, Kotaro; Hino, Ichiro; Sato, Katashi; Ohkawa, Motoomi [Kagawa Medical Univ., Miki (Japan)

2001-08-01

We evaluated the usefulness of three-dimensional images with multislice CT in the temporal bone diseases. Fifty-nine cases (26 with medial otitis, 8 choresteatoma, 10 congenital malformation, 3 high jugular bulb, 2 otosclerosis, and 10 others) were included in this study. In the ossicular and inner ear lesions, oblique multiplanar images of the long axis of each ossicle was useful the detection of abnormality. Structural deformity of ossicles and bony labyrinth were clearly delineated by surface rendering images. (author)

Detection of hepatic VX2 carcinomas with ferucarbotran-enhanced magnetic resonance imaging in rabbits: Comparison of nine pulse sequences

International Nuclear Information System (INIS)

Kim, Seong Hyun; Choi, Dongil; Lim, Hyo K.; Kim, Min Ju; Jang, Kyung Mi; Kim, Seung Hoon; Lee, Won Jae; Lee, Jongmee; Jeon, Yong Hwan; Lim, Jae Hoon

2006-01-01

Objective: To compare the diagnostic performance of a variety of magnetic resonance imaging (MRI) sequences, in order to identify the most effective ferucarbotran-enhanced sequence for the detection of multiple small hepatic VX2 carcinomas in rabbits. Methods: Fifteen rabbits with experimentally induced 135 VX2 carcinomas in the liver underwent ferucarbotran-enhanced MRI using the following nine pulse sequences: a fat-suppressed fast spin-echo (FSE) sequence with two echo times (TE) (proton density- and T2-weighted images), four different T2*-weighted fast multiplanar GRASS (gradient-recalled acquisition in the steady state) (FMPGR) with the combination of three TEs (9, 12, 15 ms, respectively) and two flip angles (20 deg., 80 deg., respectively), T2*-weighted fast multiplanar spoiled GRASS (FMPSPGR), T1-weighted FMPSPGR, and dynamic T1-weighted FMPSPGR. All images were reviewed by three radiologists with quantitative and qualitative analysis. Results: Tumor-to-liver contrast-to-noise ratio of the proton density-weighted FSE sequence was significantly higher than those of the others (p o ) images were superior to those of the others and for the detection of very small hepatic tumors of less than 5 mm, the sensitivities of these sequences were less than 30%. Conclusion: Ferucarbotran-enhanced T2- and proton density-weighted FSE and T2*-weighed FMPGR (TE/flip angle, 12/20 o ) images were found to be the most effective pulse sequences for the detection of multiple small hepatic VX2 carcinomas but these sequences were limited in the detection of very small hepatic tumors of less than 5 mm in size

Applicability of the 3D-VIBE sequence to whole brain imaging

International Nuclear Information System (INIS)

Makabe, Takeshi; Nakamura, Manami; Moriyama, Ryo

2009-01-01

The volumetric interpolated breath-hold examination (VIBE) method has been developed imaging also holds its breath in an abdomen, and to do three-dimensional T1WI in possible time in gradient echo sequence, and applied to dynamic study mainly and planning for time reduction using an interpolation and partial fourier. We considered the condition for imaging to do whole brain as high resolution image using VIBE. Even if base matrix was maintained when an interpolation and partial fourier were used too much excessively by Phantom experiment, the resolution of multiplanar reconstruction (MPR) image fell. There was a limit of the interpolation therefore to maintain the resolution as voxel. Signal-to-noise ratio (SNR) fell by flip angle (FA) increase by the applicability to the head, and peak existed in about 15 deg in contrast-to-noise ratio (CNR) of white matter and gray matter. Therefore by it's clinical and optimizing the imaging condition of VIBE, whole brain, it was imaging possible in about 3 minutes as high resolution image. (author)

Magnetic resonance imaging of the elbow. Part I: Normal anatomy, imaging technique, and osseous abnormalities

International Nuclear Information System (INIS)

Kijowski, Richard; Tuite, Michael; Sanford, Matthew

2004-01-01

Part I of this comprehensive review on magnetic resonance imaging of the elbow discusses normal elbow anatomy and the technical factors involved in obtaining high-quality magnetic resonance images of the elbow. Part I also discusses the role of magnetic resonance imaging in evaluating patients with osseous abnormalities of the elbow. With proper patient positioning and imaging technique, magnetic resonance imaging can yield high-quality multiplanar images which are useful in evaluating the osseous structures of the elbow. Magnetic resonance imaging can detect early osteochondritis dissecans of the capitellum and can be used to evaluate the size, location, stability, and viability of the osteochondritis dissecans fragment. Magnetic resonance imaging can detect early stress injury to the proximal ulna in athletes. Magnetic resonance imaging can detect radiographically occult fractures of the elbow in both children and adults. Magnetic resonance imaging is also useful in children to further evaluate elbow fractures which are detected on plain-film radiographs. (orig.)

Dynamic Neuromuscular Control of the Lower Limbs in Response to Unexpected Single-Planar versus Multi-Planar Support Perturbations in Young, Active Adults.

Science.gov (United States)

Malfait, Bart; Staes, Filip; de Vries, Aijse; Smeets, Annemie; Hawken, Malcolm; Robinson, Mark A; Vanrenterghem, Jos; Verschueren, Sabine

2015-01-01

An anterior cruciate ligament (ACL) injury involves a multi-planar injury mechanism. Nevertheless, unexpected multi-planar perturbations have not been used to screen athletes in the context of ACL injury prevention yet could reveal those more at risk. The objective of this study was to compare neuromuscular responses to multi-planar (MPP) and single-planar perturbations (SPP) during a stepping-down task. These results might serve as a basis for future implementation of external perturbations in ACL injury screening programs. Thirteen young adults performed a single leg stepping-down task in eight conditions (four MPP and four SPP with a specified amplitude and velocity). The amplitudes of vastus lateralis (VL), vastus medialis (VM), hamstrings lateralis (HL), hamstrings medialis (HM) EMG activity, medio-lateral and anterior-posterior centre of mass (COM) displacements, the peak knee flexion and abduction angles were compared between conditions using an one-way ANOVA. Number of stepping responses were monitored during all conditions. Significantly greater muscle activity levels were found in response to the more challenging MPP and SPP compared to the less challenging conditions (p neuromuscular activity were found between the MPP conditions and their equivalents in the SPP. Eighteen stepping responses were monitored in the SPP versus nine in the MPP indicating that the overall neuromuscular control was even more challenged during the SPP which was supported by greater COM displacements in the SPP. The more intense MPP and SPP evoked different neuromuscular responses resulting in greater muscle activity levels compared to small perturbations. Based on the results of COM displacements and based on the amount of stepping responses, dynamic neuromuscular control of the knee joint appeared less challenged during the MPP. Therefore, future work should investigate extensively if other neuromuscular differences (i.e. co-activation patterns and kinetics) exist between MPP

CT imaging of bronchus related to solitary pulmonary lesion: comparison of minimum intensity projection and multi-planar reconstruction

International Nuclear Information System (INIS)

Zhou Jun; Shan Fei; Zhang Zhiyong; Yang Shan; Zhang Xingwei; Wu Dong; Zhan Songhua

2011-01-01

Objective: To investigate the clinical value of 64-slice computed tomography with MinIP and MPR for imaging the bronchus related to a solitary pulmonary lesion (SPL). Methods: Seventy-five subjects with solitary pulmonary lesions underwent chest 64-slice CT and their bronchi were analyzed retrospectively. All images of thin-section (0.625 mm) were reconstructed with MPR and MinIP into images of 1, 2, 3, and 5 mm thickness and 1 mm gap in two orthogonal planes along the long axis of bronchus related to the SPL. The image quality of four series of MinIP and MPR images was evaluated in the aspect of bronchus visibility and pulmonary vascular masking. One-way ANOVA with Bonferroni correction and interclass correlation coefficient were used in the statistical analysis. Results: (1) The mean scores of display of the bronchi on MinIP images of four series (4.85, 4.77 and 4.84, 4.63 and 4.67, 4.25 and 4.28, in 1, 2, 3, and 5 mm thickness, respectively) and on MPR images of 1 or 2 mm thickness (4.77 and 4.76, 4.04 and 4.27, in 1 and 2 mm thickness, respectively) were good or excellent. MPR images of 1 mm thickness and MinIP images of 1-3 mm thickness showed no significant differences (t=0.318, P> 0.05 for all), but they were superior to MinIP images of 5 mm thickness (t=6.318 and 6.610, P 0.05). (2) The effect of suppression of pulmonary vascular markings on MinIP images was better with the increase of slice thickness (F= 45.312 and 40.415, P<0.01). The mean scores of MinIP images of 3 mm and 5 mm thickness (4.67 and 4.64, 5.00 and 4.97, for 3 and 5 mm thickness, respectively) were good or excellent, but MinIP images of 2 mm thickness were just acceptable. Conclusion: MinIP images of 3 mm thickness may display the bronchus related to SPL more clearly. (authors)

Abducens nerve enhancement demonstrated by multiplanar reconstruction of contrast-enhanced three-dimensional MRI

International Nuclear Information System (INIS)

Hosoya, T.; Adachi, M.; Sugai, Y.; Yamaguchi, K.; Yamaguchi, K.; Kato, T.

2001-01-01

We describe contrast enhancement of the cisternal portion of the abducens nerve and discuss its clinical significance. We examined 67 patients with ophthalmoplegia using contrast-enhanced 3-dimensional (3D) MRI with multiplanar reconstruction along the nerves and found 16 patients (ten men, six women), aged 10-73 years (mean 34.4 years), with contrast enhancement of the abducens nerve. Of the 36 patients who had an abducens palsy, 14 (39 %) showed contrast enhancement. In the 16 patients, 23 abducens nerves enhanced; 13 were symptomatic and 10 asymptomatic at the time. The causes were disseminated tumour (1), an inflammatory process (3), trauma (2), ischaemia (2) and autoimmune diseases (8), such as the Miller Fisher syndrome, acute ophthalmoparesis, polyneuropathy and multiple sclerosis. Abducens and/or oculomotor nerve enhancement was the only abnormality on MRI in the patients with traumatic or ischaemic neuropathy or autoimmune diseases. There were 14 patients who recovered fully within 1-6 months after treatment, and resolution of the enhancement correlated well with recovery. (orig.)

Abducens nerve enhancement demonstrated by multiplanar reconstruction of contrast-enhanced three-dimensional MRI

Energy Technology Data Exchange (ETDEWEB)

Hosoya, T.; Adachi, M.; Sugai, Y. [Dept. of Radiology, Yamagata University School of Medicine (Japan); Yamaguchi, K.; Yamaguchi, K. [Dept. of Ophthalmology, Yamagata University School of Medicine (Japan); Kato, T. [3. Dept. of Internal Medicine, Yamagata University School of Medicine (Japan)

2001-04-01

We describe contrast enhancement of the cisternal portion of the abducens nerve and discuss its clinical significance. We examined 67 patients with ophthalmoplegia using contrast-enhanced 3-dimensional (3D) MRI with multiplanar reconstruction along the nerves and found 16 patients (ten men, six women), aged 10-73 years (mean 34.4 years), with contrast enhancement of the abducens nerve. Of the 36 patients who had an abducens palsy, 14 (39 %) showed contrast enhancement. In the 16 patients, 23 abducens nerves enhanced; 13 were symptomatic and 10 asymptomatic at the time. The causes were disseminated tumour (1), an inflammatory process (3), trauma (2), ischaemia (2) and autoimmune diseases (8), such as the Miller Fisher syndrome, acute ophthalmoparesis, polyneuropathy and multiple sclerosis. Abducens and/or oculomotor nerve enhancement was the only abnormality on MRI in the patients with traumatic or ischaemic neuropathy or autoimmune diseases. There were 14 patients who recovered fully within 1-6 months after treatment, and resolution of the enhancement correlated well with recovery. (orig.)

Usefulness of MPR images of nephrogram in ureteropelvic junction stenosis

International Nuclear Information System (INIS)

Usui, Nobutaka; Munechika, Hirotsugu

2005-01-01

The study was to see if the multi-planar reconstruction (MPR) images of nephrogram were useful to evaluate the causative lesion of ureteropelvic junction (UPJ) stenosis. Thirty-two cases with UPJ stenosis were selected retrospectively for evaluation. MPR images were compared between nephrogram and ureterogram to see which was more useful for evaluation of the causative lesion. Most of the lesions were evaluated better in nephrogram or equal to ureterogram except for one case of a small ureteral tumor. MPR images in nephrogram were useful for evaluation of crossing vessels and a ureteral tumor. Benign stricture and calculi were also confirmed by the images. (author)

Method of multiplanar emission tomography and apparatus therefor

International Nuclear Information System (INIS)

Gottschalk, S.C.; Smith, K.A.; Wake, R.H.

1981-01-01

A method of emission tomography using a gamma camera and a rotating collimator having an array of a large number of slanted, small diameter holes. A planar projection corresponding to each angular orientation assumed by the collimator is recorded. From these series of planar projections, a three-dimensional simulation model is reconstructed by an iterative algorithm which approximates the emitting object. The simulated model comprises multiple separable planes

MR defecography at 1.5 Tesla with radial real-time imaging at a reduced FOV

International Nuclear Information System (INIS)

Tacke, J.; Nolte-Ernsting, C.; Glowinski, A.; Adam, G.; Guenther, R.W.

1999-01-01

Purpose: To evaluate a new technique for MR defecography with real-time imaging using radial k-space profiles. Materials and Methods: A catheter-mounted condom was inserted into the rectum of 16 patients and filled in situ by a mixture of Nestargel trademark and Gadolinium. After multiplanar imaging of the pelvis by high resolution T 2 -weighted turbo-spin echo sequences, defecation was imaged by a gradient echo sequence with radial k-space filling using a reduced field of view (rFOV) in real-time. The documentation was performed on an S-VHS recorder. Results: At a constant background signal, radial k-space filling yields a real-time impression. An interactive software allowed the operator to modify the slice thickness, slice plane, flip angle and slice angulation during scanning, resulting in an optimum imaging quality of the defecation. Conclusions: This new imaging technique allows real-time MR defecography in a high-field scanner and provides all anatomical and functional information of the defecation. (orig.) [de

Computed tomography imaging for superior semicircular canal dehiscence syndrome

International Nuclear Information System (INIS)

Dobeli, Karen

2006-01-01

Superior semicircular canal dehiscence is a newly described syndrome of sound and/or pressure induced vertigo. Computed tomography (CT) imaging plays an important role in confirmation of a defect in the bone overlying the canal. A high resolution CT technique utilising 0.5 mm or thinner slices and multi-planar reconstructions parallel to the superior semicircular canal is required. Placement of a histogram over a suspected defect can assist CT diagnosis

3 T MR 3D fast imaging employing steady state acquisition demonstrating branches of intraparotid facial nerve, parotid duct, and relation with parotid tumors

International Nuclear Information System (INIS)

Li Yan; Li Chuanting; Zhang Dongsheng; Ai Bin; Zhang Weidong; Wu Lebin

2010-01-01

Objective: To investigate the usefulness of 3 T MRI 3D-FIESTA in the evaluation of the intraparotid components of the facial nerve and parotid duct, and compare them with surgical findings. Methods: Twenty-two cases with parotid benign tumors were scanned with conventional and 3D-FIESTA sequences on 3 T MRI scanner. Postprocessed multiplanar images were obtained with the workstation. Parotid ducts and facial nerves and tumors were identified on these images. The relationship of the tumors to the facial nerves and Parotid ducts was confirmed at surgery. Results: Various types of parotid benign tumors had their characteristics on 3 T MR imaging. Parotid benign tumors mainly showed hypo-intensity on T 1 WI in 21 cases, and hyper-intensity on T 2 WI in 22 cases. But on 3D-FIESTA images, they appeared hypointensity (10 cases) or high intensity (12 cases) due to different types. Facial nerves in parotid appeared as linear structures with hypo-inteusity. The indication of the main trunks were 16 and 18 cases for T 1 WI and T 2 WI images, while on 3D-FIESTA images, the main trunks and cervicofacial and temporofacial divisions of the facial nerves were found in 22, 21,22 cases. Parotid ducts appeared as structures with hypo-intensity on T 1 WI and hyper-intensity on multiplanar images (14, 20, 22 cases). Compared with surgical results, the main trunks of the facial nerve were correctly showed by 3D-FIESTA images in 20 cases. However, in 2 cases they were not located in the operation because of shifting. Conclusion: 3 T MR 3D-FIESTA imaging could depict the extracranial facial nerve and the parotid duct in the parotid gland, which is useful for preoperative evaluation of parotid gland tumors. (authors)

Multi-Detector Computed Tomography Imaging Techniques in Arterial Injuries

Directory of Open Access Journals (Sweden)

Cameron Adler

2018-04-01

Full Text Available Cross-sectional imaging has become a critical aspect in the evaluation of arterial injuries. In particular, angiography using computed tomography (CT is the imaging of choice. A variety of techniques and options are available when evaluating for arterial injuries. Techniques involve contrast bolus, various phases of contrast enhancement, multiplanar reconstruction, volume rendering, and maximum intensity projection. After the images are rendered, a variety of features may be seen that diagnose the injury. This article provides a general overview of the techniques, important findings, and pitfalls in cross sectional imaging of arterial imaging, particularly in relation to computed tomography. In addition, the future directions of computed tomography, including a few techniques in the process of development, is also discussed.

The contribution of magnetic resonance imaging of the larynx compared with that of computed tomography in the pretreatment assessment of laryngeal cancers based on a series of ninety operated cases

International Nuclear Information System (INIS)

Giron, J.; Joffre, P.; Serres-Cousine, O.; Castan, P.; Senac, J.P.

1990-01-01

The authors report a prospective and comparative study of the pre-operative staging of 90 laryngeal carcinomas by CT and MRI, with blind analysis of each examination. The radio-anatomic correlations and the inter-method correlations (CT versus MRI) are reported. According to the authors MRI seems to be the method of choice because of its capabilities in soft tissues differentiation and because of its multiplanar representation. The motion artefacts are resolved by the fast imaging technique and the spatial resolution is optimized by special surface coils [fr

Simplifying the Exploration of Volumetric Images: Development of a 3D User Interface for the Radiologist’s Workplace

OpenAIRE

Teistler, M.; Breiman, R. S.; Lison, T.; Bott, O. J.; Pretschner, D. P.; Aziz, A.; Nowinski, W. L.

2007-01-01

Volumetric imaging (computed tomography and magnetic resonance imaging) provides increased diagnostic detail but is associated with the problem of navigation through large amounts of data. In an attempt to overcome this problem, a novel 3D navigation tool has been designed and developed that is based on an alternative input device. A 3D mouse allows for simultaneous definition of position and orientation of orthogonal or oblique multiplanar reformatted images or slabs, which are presented wit...

3D MRI of the colon: methods and first results of 5 patients; 3D-MRT des Kolons: Methodik und erste Ergebnisse

Energy Technology Data Exchange (ETDEWEB)

Luboldt, W; Bauerfeind, P; Pelkonen, P; Steiner, P; Krestin, G P; Debatin, J F [MRI-Zentrum, Dept. Diagnostische Radiologie, Universitaetsspital, Zurich (Switzerland)

1997-09-01

Purpose: `Exoscopic` and endoscopic identification of colorectal pathologies via MRI. Methods: 5 patients (36-88 years), two normal and three with different colorectal pathologies (diverticular disease, polyps and carcinoma of the colon), were examined by MRI after colonoscopy. Subsequent to filling of the colon with a gadolinium-water mixture under MRI-monitoring, 3D-data sets of the colon were acquired in prone and supine positions over a 28 sec breathold interval. Subsequently multiplanar T{sub 1}-weighted 2D-sequences were acquired before and following i.v. administration of Gd-DTPA (0.1 mmol/kg BW). All imaging was performed in the coronal orientation. The 3D-data were interactively analysed based on various displays: Maximum intensity projection (MIP), surface shadowed display (SSD), multiplanar reconstruction (MPR), virtual colonoscopy (VC). Results: All of the colorectal pathologies could be interactively diagnosed by MPR. On MIP images some pathologies were missed. VC presented the morphology of colon haustra as well as of all endoluminally growing lesions in a manner similar to endoscopy. The colon masses showed uptake of contrast media and could thus be differentiated from air or faeces. (orig./AJ) [Deutsch] Ziel: Externe und endoskopische Identifizierung kolorektaler Pathologien mittels MRT. Material und Methoden: 5 Patienten (36-88 Jahre), zwei mit Normalbefund, drei mit verschiedenen kolorektalen pathologischen Befunden (Divertikulose, Polypen, Karzinom), wurden nach der Kolonoskopie mit der MRT untersucht. Dazu wurde das Kolon unter MR-Sichtkontrolle mit einer Gadolinium-Wasser-Mischung gefuellt und als 3D-Datensatz atemangehalten in Bauch- und Rueckenlage aufgenommen. Anschliessend wurden multiplanare, T{sub 1}-gewichtete 2D-Sequenzen vor und nach i.v. Gd-DTPA-Gabe akquiriert. Die 3D-Datensaetze wurden interaktiv unter Zuhilfenahme verschiedener Darstellungsformen analysiert: Maximale Intensitaetsprojektion (MIP), Oberflaechendarstellung

Parasellar meningiomas: magnetic resonance imaging findings

International Nuclear Information System (INIS)

Santos, Alair Augusto S.M.D. dos; Fontes, Cristina Asvolinsque P.

2001-01-01

We reviewed 22 cases of patients with parasellar meningiomas evaluated with magnetic resonance imaging (MRI) in private clinics of the cities of Niteroi and Rio de Janeiro, Rio de Janeiro State, Brazil. Our aim was to characterize the imaging findings in this type of tumor. MRI scanners with 0.5 and 1.0 Tesla magnets were used for the acquisition of multiplanar T1-weighted (pre-and post-gadolinium administration) and T2-weighted images. The main symptoms observed were headache and visual disturbances. Hyperprolactinaemia was observed in only one patient. The most frequent imaging finding was a parasellar mass which appeared hypointense on T1-weighted and hyperintense on T2-weighted images, and enhanced intensively after gadolinium administration. MRI is useful to demonstrate the lesion and to asses the damage to adjacent structures, particularly when the patient presents visual disturbances due to involvement of the cavernous sinuses. (author)

Advanced MR brain imaging. Why?

International Nuclear Information System (INIS)

Huisman, Thierry A.G.M.; Tekes, Aylin

Repeated examinations, also known as so-called 'follow-up examinations' are nowadays frequently used to decide whether or not a chosen treatment should be continued, adapted or discontinued. The side effects of X-rays on biological systems, especially on developing systems did, however, limit the use of X-rays in children. The development of high-resolution, non-ionizing imaging modalities like US and MRI revolutionized diagnostic medicine for the second time after the discovery of X-rays. US is nowadays an essential imaging modality in paediatrics; it can be performed at the bedside, has no side effects on the child, is widely available, well accepted by parents and can be repeated without limitations. MRI with its high spatial resolution, different imaging contrasts and multiplanar capabilities has grown into a second line imaging modality if plain films and US cannot make the diagnosis accurately or reliably. A third revolution in diagnostic imaging occurred as MRI allowed studying biological processes and functions non-invasively. (orig.)

Vaginal Masses: Magnetic Resonance Imaging Features with Pathologic Correlation

International Nuclear Information System (INIS)

Elsayes, K.M.; Narra, V.R.; Dillman, J.R.; Velcheti, V.; Hameed, O.; Tongdee, R.; Menias, C.O.

2007-01-01

The detection of vaginal lesions has increased with the expanding use of cross-sectional imaging. Magnetic resonance imaging (MRI) - with its high-contrast resolution and multiplanar capabilities - is often useful for characterizing vaginal masses. Vaginal masses can be classified as congenital, inflammatory, cystic (benign), and neoplastic (benign or malignant) in etiology. Recognition of the typical MR imaging features of such lesions is important because it often determines the treatment approach and may obviate surgery. Finally, vaginal MR imaging can be used to evaluate post-treatment changes related to previous surgery and radiation therapy. In this article, we will review pertinent vaginal anatomy, vaginal and pelvic MRI technique, and the MRI features of a variety of vaginal lesions with pathological correlation

MR imaging of the pediatric spine: Comparison of myelography, MCT, and surgery

International Nuclear Information System (INIS)

Davis, P.C.; Hoffman, J.C.; Ball, T.I.; Wyly, J.B.; Braun, I.F.; Fry, S.M.

1986-01-01

Results of MR imaging of 53 pediatric patients with suspected spinal abnormalities were compared findings on metrizamide myelography, MCT, and surgery. Prototype surface coil studies with multisection multiplanar imaging (0.5 and 1.5 T) using T1-weighted sequences were optimum for anatomic definition, while T2-weighted sequences were utilized for intramedullary pathology. Diseases studied included neoplasia, infection, trauma, scoliosis, and dysrhaphsium. Surface coils were essential for imaging the thoracic and lumbar spine. MR imaging yielded approximately equivalent information to that obtained on myelography or MCT in 25 of 31 patients. Limitations to MR imaging included bony spurs, small eccentric lesions, tumor seeding, metal artifacts, postoperative scarring, and motion. With further refinements, MR imaging may replace more invasive techniques for pediatric spinal imaging

The study on the X-ray correction method of long fracture displacement

International Nuclear Information System (INIS)

Jia Bin; Huang Ailing; Chen Fuzhong; Men Chunyan; Sui Chengzong; Cui Yiming; Yang Yundong

2010-01-01

Objective: To explore the image correction of fracture displacement by conventional X-ray photography (ortho tropic and lateral) and test by computed tomography (CT). Methods: The correction method of fracture displacement was designed according to geometry of X-ray photography. Selected one midhumeral fracture specimen which designed with lateral shift and angular displacement, and scanned from anteroposterior and position respectively, and also volume scanned using CT, the data obtained from volume scan were processed using multiplanar reconstruction (MPR) and shaded surface display (SSD). The displacement data relied on X-ray image, CT with MPR and SSD processing, actual design of specimens were compared respectively. Results: The direction and degree of displacement among correction data of X-ray images and the data from MPR and SSD, actual design of specimen were little difference, location difference <1.5 mm, degree difference <1.5 degree. Conclusion: It is really reliable for fracture displacement by conventional X-ray photography with coordinate correction, and it is helpful to obviously improve the diagnostic accuracy of the degree of fracture displacement. (authors)

MR imaging of oropharynx and oral cavity

International Nuclear Information System (INIS)

Vogl, T.; Markl, A.F.; Bruning, R.; Greves, G.; Kang, K.; Lissner, J.A.

1988-01-01

The effect of intravenously administered Gd-DTPA on signal intensity, in the oropharynx and oral cavity was analyzed, in comparison with plain imaging the examinations were carried out on 150 patients, with a 1.5-T magnetic resonance (MR) imaging unit. During and after the application of Gd-DTPA, flash images with a repetition time of 30, an echo time of 12 msec, and a 20 0 flip angle were acquired over a period of 7 minutes. In 89 patients, malignant tumors were discovered, located primarily in the oropharynx and oral cavity. Plain MR imaging was equal to or better than computed tomograph in all patients except five. Marked contrast enhancement was observed in carcinomas, sarcomas, and inflammation. The enhancement of signal intensity versus time allowed a better differentiation of histologic features. MR imaging contributes substantially to the imaging of the oropharynx and oral cavity by improved soft-tissue contrast and the capacity for multiplanar imaging

Osteoblastic lesion screening with an advanced post-processing package enabling in-plane rib reading in CT-images.

Science.gov (United States)

Seuss, Hannes; Dankerl, Peter; Cavallaro, Alexander; Uder, Michael; Hammon, Matthias

2016-05-20

To evaluate screening and diagnostic accuracy for the detection of osteoblastic rib lesions using an advanced post-processing package enabling in-plane rib reading in CT-images. We retrospectively assessed the CT-data of 60 consecutive prostate cancer patients by applying dedicated software enabling in-plane rib reading. Reading the conventional multiplanar reconstructions was considered to be the reference standard. To simulate clinical practice, the reader was given 10 s to screen for sclerotic rib lesions in each patient applying both approaches. Afterwards, every rib was evaluated individually with both approaches without a time limit. Sensitivities, specificities, positive/negative predictive values and the time needed for detection were calculated depending on the lesion's size (largest diameter  10 mm). In 53 of 60 patients, all ribs were properly displayed in plane, in five patients ribs were partially displayed correctly, and in two patients none of the ribs were displayed correctly. During the 10-s screening approach all patients with sclerotic rib lesions were correctly identified reading the in-plane images (including the patients without a correct rib segmentation), whereas 14 of 23 patients were correctly identified reading conventional multiplanar images. Overall screening sensitivity, specificity, and positive/negative predictive values were 100/27.0/46.0/100 %, respectively, for in-plane reading and 60.9/100/100/80.4 %, respectively, for multiplanar reading. Overall diagnostic (no time limit) sensitivity, specificity, and positive/negative predictive values of in-plane reading were 97.8/92.8/74.6/99.5 %, respectively. False positive results predominantly occurred for lesions <5 mm in size. In-plane reading of the ribs allows reliable detection of osteoblastic lesions for screening purposes. The limited specificity results from false positives predominantly occurring for small lesions.

Review methods for image segmentation from computed tomography images

International Nuclear Information System (INIS)

Mamat, Nurwahidah; Rahman, Wan Eny Zarina Wan Abdul; Soh, Shaharuddin Cik; Mahmud, Rozi

2014-01-01

Image segmentation is a challenging process in order to get the accuracy of segmentation, automation and robustness especially in medical images. There exist many segmentation methods that can be implemented to medical images but not all methods are suitable. For the medical purposes, the aims of image segmentation are to study the anatomical structure, identify the region of interest, measure tissue volume to measure growth of tumor and help in treatment planning prior to radiation therapy. In this paper, we present a review method for segmentation purposes using Computed Tomography (CT) images. CT images has their own characteristics that affect the ability to visualize anatomic structures and pathologic features such as blurring of the image and visual noise. The details about the methods, the goodness and the problem incurred in the methods will be defined and explained. It is necessary to know the suitable segmentation method in order to get accurate segmentation. This paper can be a guide to researcher to choose the suitable segmentation method especially in segmenting the images from CT scan

Imaging in the diagnosis of juvenile nasopharyngeal angiofibroma

Directory of Open Access Journals (Sweden)

Satyaranjan Mishra

2013-01-01

Full Text Available Juvenile nasopharyngeal angiofibroma (JNA is a rare, benign, highly vascular, and locally aggressive tumor that predominantly occurs in adolescent males. Usually, the presenting symptom is a painless nasal obstruction or epistaxis; however, other symptoms may develop depending on the size and extent of the tumor mass. Owing to the vascularity of the tumor, incisional biopsy is not attempted. The diagnosis is dependent on multiplanar imaging modalities like Computed Tomography (CT, Magnetic Resonance Imaging (MRI, and Angiography. These imaging modalities help in assessing the tumor mass, pre-operative embolization of the feeder vessel, and treatment planning. Usually, patients with JNA are diagnosed by otorhinolaryngologists, but here, we present a rare case of JNA reporting to the dental hospital due to a tender palatal swelling.

Detection of tibial condylar fractures using 3D imaging with a mobile image amplifier (Siemens ISO-C-3D): Comparison with plain films and spiral CT

International Nuclear Information System (INIS)

Kotsianos, D.; Rock, C.; Wirth, S.; Linsenmaier, U.; Brandl, R.; Fischer, T.; Pfeifer, K.J.; Reiser, M.; Euler, E.; Mutschler, W.

2002-01-01

Purpose: To analyze a prototype mobile C-arm 3D image amplifier in the detection and classification of experimental tibial condylar fractures with multiplanar reconstructions (MPR). Method: Human knee specimens (n=22) with tibial condylar fractures were examined with a prototype C-arm (ISO-C-3D, Siemens AG), plain films (CR) and spiral CT (CT). The motorized C-arm provides fluoroscopic images during a 190 orbital rotation computing a 119 mm data cube. From these 3D data sets MP reconstructions were obtained. All images were evaluated by four independent readers for the detection and assessment of fracture lines. All fractures were classified according to the Mueller AO classification. To confirm the results, the specimens were finally surgically dissected. Results: 97% of the tibial condylar fractures were easily seen and correctly classified according to the Mueller AO classification on MP reconstruction of the ISO-C-3D. There is no significant difference between ISO-C and CT in detection and correct classification of fractures, but ISO-CD-3D is significant by better than CR. (orig.) [de

Improved image alignment method in application to X-ray images and biological images.

Science.gov (United States)

Wang, Ching-Wei; Chen, Hsiang-Chou

2013-08-01

Alignment of medical images is a vital component of a large number of applications throughout the clinical track of events; not only within clinical diagnostic settings, but prominently so in the area of planning, consummation and evaluation of surgical and radiotherapeutical procedures. However, image registration of medical images is challenging because of variations on data appearance, imaging artifacts and complex data deformation problems. Hence, the aim of this study is to develop a robust image alignment method for medical images. An improved image registration method is proposed, and the method is evaluated with two types of medical data, including biological microscopic tissue images and dental X-ray images and compared with five state-of-the-art image registration techniques. The experimental results show that the presented method consistently performs well on both types of medical images, achieving 88.44 and 88.93% averaged registration accuracies for biological tissue images and X-ray images, respectively, and outperforms the benchmark methods. Based on the Tukey's honestly significant difference test and Fisher's least square difference test tests, the presented method performs significantly better than all existing methods (P ≤ 0.001) for tissue image alignment, and for the X-ray image registration, the proposed method performs significantly better than the two benchmark b-spline approaches (P < 0.001). The software implementation of the presented method and the data used in this study are made publicly available for scientific communities to use (http://www-o.ntust.edu.tw/∼cweiwang/ImprovedImageRegistration/). cweiwang@mail.ntust.edu.tw.

Oculomotor paralysis: 3D-CISS MR imaging with MPR in the evaluation of neuralgic manifestation and the adjacent structures

Energy Technology Data Exchange (ETDEWEB)

Sun Xiaoli; Liang Changhu [Shandong Medical Imaging Research Institute, Shandong University, Jing-wu Road No. 324, Jinan 250021 (China); Liu Cheng [Shandong Medical Imaging Research Institute, Shandong University, Jing-wu Road No. 324, Jinan 250021 (China)], E-mail: sdsxl2005@126.com; Liu Shuwei; Deng Kai; He Jingzhen [Shandong Medical Imaging Research Institute, Shandong University, Jing-wu Road No. 324, Jinan 250021 (China)

2010-02-15

Purpose: To evaluate the value of three-dimensional (3D) constructive interference in steady-state (CISS) magnetic resonance (MR) imaging with multi-planar reconstruction (MPR) in displaying the relationship between the oculomotor nerve and its adjacent structures for patients with oculomotor paralysis. Materials and methods: 17 consecutive patients with oculomotor paralysis were examined with 3D-CISS and conventional spin-echo (SE) sequences on a 1.5-Tesla MR system. Original transverse and MPR images were used for image interpretation. The features of the oculomotor nerve and its adjacent structures were identified. The diagnosis was surgically confirmed in all patients. Results: Through 3D-CISS with MPR images, obvious relationship of the oculomotor nerve and its adjacent structures was demonstrated on 17 patients. Of those oculomotor nerves, 15 were compressed by the arteries (n = 15), one by the craniopharyngioma (n = 1), and another one by the neurofibroma (n = 1). Conclusion: 3D-CISS MR imaging with MPR provides an excellent way to characterize the relationship between the nerve and its adjacent structures in the cisternal segment of the oculomotor nerve in the patients with oculomotor paralysis. Moreover, this method shows anatomical details for imaging diagnosis and surgical procedure.

Oculomotor paralysis: 3D-CISS MR imaging with MPR in the evaluation of neuralgic manifestation and the adjacent structures

International Nuclear Information System (INIS)

Sun Xiaoli; Liang Changhu; Liu Cheng; Liu Shuwei; Deng Kai; He Jingzhen

2010-01-01

Purpose: To evaluate the value of three-dimensional (3D) constructive interference in steady-state (CISS) magnetic resonance (MR) imaging with multi-planar reconstruction (MPR) in displaying the relationship between the oculomotor nerve and its adjacent structures for patients with oculomotor paralysis. Materials and methods: 17 consecutive patients with oculomotor paralysis were examined with 3D-CISS and conventional spin-echo (SE) sequences on a 1.5-Tesla MR system. Original transverse and MPR images were used for image interpretation. The features of the oculomotor nerve and its adjacent structures were identified. The diagnosis was surgically confirmed in all patients. Results: Through 3D-CISS with MPR images, obvious relationship of the oculomotor nerve and its adjacent structures was demonstrated on 17 patients. Of those oculomotor nerves, 15 were compressed by the arteries (n = 15), one by the craniopharyngioma (n = 1), and another one by the neurofibroma (n = 1). Conclusion: 3D-CISS MR imaging with MPR provides an excellent way to characterize the relationship between the nerve and its adjacent structures in the cisternal segment of the oculomotor nerve in the patients with oculomotor paralysis. Moreover, this method shows anatomical details for imaging diagnosis and surgical procedure.

Magnetic resonance imaging of the abdomen

International Nuclear Information System (INIS)

Kulkarni, M.V.

1986-01-01

MRI of the abdomen currently competes with CT and ultrasonography as an imaging technique for abdominal pathology. Although ultrasonography has certain advantages, such as real-time scanning, the major comparison is to be made between MR and CT. CT has slightly superior spatial resolution and minimal motion artifacts, and enables the use of contrast agents in bowel. MR, on the other hand, has improved capabilities in contrasting soft tissues and providing multiplanar imaging. The greatest advantage of CT is the experience that the medical community has gained with it over the last decade. Further development in technology and improvement in the clinical experience with MR will be important in determining its future role in abdominal imaging. Large series of clinical trials are required for further experience. Chemical spectroscopy with proton and possibly other nuclei may improve diagnostic specificity. Paramagnetic contrast agents for bowel specification would certainly improve imaging quality. Thus, MR will play a significant role in abdominal imaging in the future

Three-dimensional isotropic fat-suppressed proton density-weighted MRI at 3 tesla using a T/R-coil can replace multiple plane two-dimensional sequences in knee imaging

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Homsi, R.; Luetkens, J.A. [Bonn Univ. (Germany). Dept. of Radiology; Gieseke, J. [Philips Healthcare, Hamburg (Germany); and others

2016-10-15

To evaluate whether a 3D proton density-weighted fat-suppressed sequence (PDwFS) of the knee is able to replace multiplanar 2D-PDwFS. 52 patients (26 men, mean age: 41.9±14.5 years) underwent magnetic resonance imaging (MRI) of the knee at 3.0 Tesla using a T/R-coil. The imaging protocol included 3 planes of 2D-PDwFS (acquisition time (AT): 6:40 min; voxel sizes: 0.40-0.63 x 0.44-0.89 x 3 mm{sup 3}) and a 3D-PDwFS (AT: 6:31 min; voxel size: 0.63 x 0.68 x 0.63 mm{sup 3}). Homogeneity of fat suppression (HFS), artifacts, and image sharpness (IS) were evaluated on a 5-point scale (5[excellent] - 1[non-diagnostic]). The sum served as a measure for the overall image quality (OIQ). Contrast ratios (CR) compared to popliteal muscle were calculated for the meniscus (MEN), anterior (ACL) and posterior cruciate ligaments (PCL). In 13 patients who underwent arthroscopic knee surgery, two radiologists evaluated the presence of meniscal, ligamental and cartilage lesions to estimate the sensitivity and specificity of lesion detection. The CR was higher in the ACL, PCL and MEN in 3D- PDwFS compared to 2D-PDwFS (p<0.01 for ACL and PCL; p=0.07 for MEN). Compared to 2D images, the OIQ was rated higher in 3D-PDwFS images (p<0.01) due to fewer artifacts and HFS despite the lower IS (p<0.01). The sensitivity and specificity of lesion detection in 3D- and 2D-PDwFS were similar. Compared to standard multiplanar 2D-PDwFS knee imaging, isotropic high spatial resolution 3D-PDwFS of the knee at 3.0T can be acquired with high image quality in a reasonable scan time. Multiplanar reformations in arbitrary planes may serve as an additional benefit of 3D-PDwFS.

A Current Review of the Meniscus Imaging: Proposition of a Useful Tool for Its Radiologic Analysis

Directory of Open Access Journals (Sweden)

Nicolas Lefevre

2016-01-01

Full Text Available The main objective of this review was to present a synthesis of the current literature in order to provide a useful tool to clinician in radiologic analysis of the meniscus. All anatomical descriptions were clearly illustrated by MRI, arthroscopy, and/or drawings. The value of standard radiography is extremely limited for the assessment of meniscal injuries but may be indicated to obtain a differential diagnosis such as osteoarthritis. Ultrasound is rarely used as a diagnostic tool for meniscal pathologies and its accuracy is operator-dependent. CT arthrography with multiplanar reconstructions can detect meniscus tears that are not visible on MRI. This technique is also useful in case of MRI contraindications, in postoperative assessment of meniscal sutures and the condition of cartilage covering the articular surfaces. MRI is the most accurate and less invasive method for diagnosing meniscal lesions. MRI allows confirming and characterizing the meniscal lesion, the type, the extension, its association with a cyst, the meniscal extrusion, and assessing cartilage and subchondral bone. New 3D-MRI in three dimensions with isotropic resolution allows the creation of multiplanar reformatted images to obtain from an acquisition in one sectional plane reconstructions in other spatial planes. 3D MRI should further improve the diagnosis of meniscal tears.

A Current Review of the Meniscus Imaging: Proposition of a Useful Tool for Its Radiologic Analysis

Science.gov (United States)

Lefevre, Nicolas; Naouri, Jean Francois; Herman, Serge; Gerometta, Antoine; Klouche, Shahnaz; Bohu, Yoann

2016-01-01

The main objective of this review was to present a synthesis of the current literature in order to provide a useful tool to clinician in radiologic analysis of the meniscus. All anatomical descriptions were clearly illustrated by MRI, arthroscopy, and/or drawings. The value of standard radiography is extremely limited for the assessment of meniscal injuries but may be indicated to obtain a differential diagnosis such as osteoarthritis. Ultrasound is rarely used as a diagnostic tool for meniscal pathologies and its accuracy is operator-dependent. CT arthrography with multiplanar reconstructions can detect meniscus tears that are not visible on MRI. This technique is also useful in case of MRI contraindications, in postoperative assessment of meniscal sutures and the condition of cartilage covering the articular surfaces. MRI is the most accurate and less invasive method for diagnosing meniscal lesions. MRI allows confirming and characterizing the meniscal lesion, the type, the extension, its association with a cyst, the meniscal extrusion, and assessing cartilage and subchondral bone. New 3D-MRI in three dimensions with isotropic resolution allows the creation of multiplanar reformatted images to obtain from an acquisition in one sectional plane reconstructions in other spatial planes. 3D MRI should further improve the diagnosis of meniscal tears. PMID:27057352

COMPARISON OF IMAGE ENHANCEMENT METHODS FOR CHROMOSOME KARYOTYPE IMAGE ENHANCEMENT

Directory of Open Access Journals (Sweden)

Dewa Made Sri Arsa

2017-02-01

Full Text Available The chromosome is a set of DNA structure that carry information about our life. The information can be obtained through Karyotyping. The process requires a clear image so the chromosome can be evaluate well. Preprocessing have to be done on chromosome images that is image enhancement. The process starts with image background removing. The image will be cleaned background color. The next step is image enhancement. This paper compares several methods for image enhancement. We evaluate some method in image enhancement like Histogram Equalization (HE, Contrast-limiting Adaptive Histogram Equalization (CLAHE, Histogram Equalization with 3D Block Matching (HE+BM3D, and basic image enhancement, unsharp masking. We examine and discuss the best method for enhancing chromosome image. Therefore, to evaluate the methods, the original image was manipulated by the addition of some noise and blur. Peak Signal-to-noise Ratio (PSNR and Structural Similarity Index (SSIM are used to examine method performance. The output of enhancement method will be compared with result of Professional software for karyotyping analysis named Ikaros MetasystemT M . Based on experimental results, HE+BM3D method gets a stable result on both scenario noised and blur image.

MR imaging features of the congenital uterine anomalies

International Nuclear Information System (INIS)

Hamcan, S.; Akgun, V.; Battal, B.; Kocaoglu, M.

2012-01-01

Full text: Introduction: Congenital uterine anomalies are common and usually asymptomatic. The agenesis, malfusion or deficient resorption of the Mullerian canals during embryogenesis may lead to these anomalies. Although ultrasonography (US) is the first step imaging technique in assessment of the uterine pathologies, it can be insufficient in differentiation of them. Magnetic resonance (MR) imaging is an adequate imaging technique in depicting pelvic anatomy and different types of uterine anomalies. Objectives and tasks: In this article, we aimed to present imaging features of the uterine anomalies. Material and methods: Pelvic MR scans of the cases who were referred to our radiology department for suspicious uterine anomaly were evaluated retrospectively. Results: We determined uniconuate uterus (type II), uterus didelphys (type III), bicornuate uterus (type IV), uterine septum (type V) and arcuate uterus (type VI) anomalies according to ASRM (American Society of Reproductive Medicine) classification. Conclusion: In cases with such pathologies leading to obstruction, dysmenorrhea or palpable pelvic mass in the puberty are the main clinical presentations. In cases without obstruction, infertility or multiple abortions can be encountered in reproductive ages. The identification of the subtype of the uterine anomalies is important for the preoperative planning of the management. MR that has multiplanar imaging capability and high soft tissue resolution is a non-invasive and the most important imaging modality for the detection and classification of the uterine anomalies

Characterization of impact damage in metallic/nonmetallic composites using x-ray computed tomography imaging

International Nuclear Information System (INIS)

Green, William H.; Wells, Joseph M.

1999-01-01

Characterizing internal impact damage in composites can be difficult, especially in structurally complex composites or those consisting of many materials. Many methods for nondestructive inspection/nondestructive testing (NDI/NDT) of materials have been known and in use for many years, including x-ray film, real-time, and digital radiographic techniques, and ultrasonic techniques. However, these techniques are generally not capable of three-dimensional (3D) mapping of complex damage patterns, which is necessary to visualize and understand damage cracking modes. Conventional x-ray radiography suffers from the loss of 3D information. Structural complexity and signal dispersion in materials with many interfaces significantly effect ultrasonic inspection techniques. This makes inspection scan interpretation difficult, especially in composites containing a number of different materials (i.e., polymer, ceramic, and metallic). X-ray computed tomography (CT) is broadly applicable to any material or test object through which a beam of penetrating radiation may be passed and detected, including metals, plastics, ceramics, metallic/nonmetallic composites, and assemblies. The principal advantage of CT is that it provides densitometric (that is, radiological density and geometry) images of thin cross sections through an object. Because of the absence of structural superposition, images are much easier to interpret than conventional radiological images. The user can quickly learn to read CT data because images correspond more closely to the way the human mind visualizes 3D structures than projection radiology (that is, film radiography, real-time radiography (RTR), and digital radiography (DR)). Any number of CT images, or slices, from scanning an object can be volumetrically reconstructed to produce a 3D attenuation map of the object. The 3D attenuation data can be rendered using multiplanar or 3D solid visualization. In multiplanar visualization there are four planes of view

Diagnostic imaging of injuries and overuse in soccer players

International Nuclear Information System (INIS)

Jonge, M.C. de; Maas, M.; Kuijk, C. van

2002-01-01

Soccer is one of the most popular sports worldwide. There is a high incidence of injuries in soccer in which several intrinsic and extrinsic factors play a part. Most injuries are minor, self-limiting and do not need extensive medical treatment or imaging. Imaging can be required for several reasons e.g. when the clinical findings are doubtful, to replace arthroscopy (i. e. of the knee) or for prognostic reasons. All imaging modalities available to the radiologist can be used but MRI is the most valuable imaging modality with its superior contrast resolution and multiplanar capabilities. Basically, injuries in the soccer player can occur anywhere in the body like in every sport. The lower extremities, more specific the knee and ankle, are however the most injured parts. (orig.) [de

Sinonasal imaging after Caldwell-Luc surgery: MDCT findings of an abandoned procedure in times of functional endoscopic sinus surgery

International Nuclear Information System (INIS)

Nemec, Stefan Franz; Peloschek, Philipp; Koelblinger, Claus; Mehrain, Sheida; Krestan, Christian Robert; Czerny, Christian

2009-01-01

Background and purpose: Today, functional endoscopic sinus surgery (FESS) is performed in most of the patients with sinonasal inflammatory disease. The postoperative imaging findings of FESS in multidetector computed tomography (MDCT) considerably differ from those of historic Caldwell-Luc (CL) maxillary sinus surgery which is an uncommon procedure today. Thus, the postoperative CL imaging findings may lead to diagnostic confusion and misinterpretation. Therefore, this study explicitly presents the MDCT findings of post-CL patients which have not been described previously. Methods: Twenty-eight patients with clinically suspected sinusitis and documented history of CL-procedure underwent 16 row MDCT (MDCT Mx8000 IDT Philips) with multiplanar reconstructions of the paranasal sinuses in the axial plane. The following parameters were used: 140 kV, 50 mAs; 16 mm x 0.75 mm detector collimation; 1 mm reconstructed slice thickness; 0.5 mm increment. The studies were reconstructed with a bone algorithm (W3000/L600; 1 mm slice thickness) in axial plane and coronal plane (3 mm slice thickness). The images were retrospectively evaluated for the presence of normal surgery-related and pathological findings. Results: Surgery-related imaging characteristics presented as follows: an anterior and a medial bony wall defect and sclerosis and sinus wall thickening were observed in all 28/28 cases (100%). Collaps of the sinus cavity was seen in 26/28 cases (92.9%). Furthermore, inflammatory disease of the operated sinus(es) was found in 23/28 cases (82.1%): 14/28 patients (50%) had inflammatory mucosal thickening of the operated sinus(es) as well as of other sinonasal cavities and 9/28 patients (32.1%) had inflammatory mucosal thickening limited to the operated sinus(es). A postoperative mucocele was depicted in 3/28 cases (10.7%). 2/28 patients (7.1%) showed neither maxillary nor other mucosal swelling. Conclusion: MDCT with multiplanar reconstructions is a precise method to evaluate

Optoelectronic imaging of speckle using image processing method

Science.gov (United States)

Wang, Jinjiang; Wang, Pengfei

2018-01-01

A detailed image processing of laser speckle interferometry is proposed as an example for the course of postgraduate student. Several image processing methods were used together for dealing with optoelectronic imaging system, such as the partial differential equations (PDEs) are used to reduce the effect of noise, the thresholding segmentation also based on heat equation with PDEs, the central line is extracted based on image skeleton, and the branch is removed automatically, the phase level is calculated by spline interpolation method, and the fringe phase can be unwrapped. Finally, the imaging processing method was used to automatically measure the bubble in rubber with negative pressure which could be used in the tire detection.

Soft tissue tumors - imaging methods

International Nuclear Information System (INIS)

Arlart, I.P.

1985-01-01

Soft Tissue Tumors - Imaging Methods: Imaging methods play an important diagnostic role in soft tissue tumors concerning a preoperative evaluation of localization, size, topographic relationship, dignity, and metastatic disease. The present paper gives an overview about diagnostic methods available today such as ultrasound, thermography, roentgenographic plain films and xeroradiography, radionuclide methods, computed tomography, lymphography, angiography, and magnetic resonance imaging. Besides sonography particularly computed tomography has the most important diagnostic value in soft tissue tumors. The application of a recently developed method, the magnetic resonance imaging, cannot yet be assessed in its significance. (orig.) [de

New mobile methods for dietary assessment: review of image-assisted and image-based dietary assessment methods.

Science.gov (United States)

Boushey, C J; Spoden, M; Zhu, F M; Delp, E J; Kerr, D A

2017-08-01

For nutrition practitioners and researchers, assessing dietary intake of children and adults with a high level of accuracy continues to be a challenge. Developments in mobile technologies have created a role for images in the assessment of dietary intake. The objective of this review was to examine peer-reviewed published papers covering development, evaluation and/or validation of image-assisted or image-based dietary assessment methods from December 2013 to January 2016. Images taken with handheld devices or wearable cameras have been used to assist traditional dietary assessment methods for portion size estimations made by dietitians (image-assisted methods). Image-assisted approaches can supplement either dietary records or 24-h dietary recalls. In recent years, image-based approaches integrating application technology for mobile devices have been developed (image-based methods). Image-based approaches aim at capturing all eating occasions by images as the primary record of dietary intake, and therefore follow the methodology of food records. The present paper reviews several image-assisted and image-based methods, their benefits and challenges; followed by details on an image-based mobile food record. Mobile technology offers a wide range of feasible options for dietary assessment, which are easier to incorporate into daily routines. The presented studies illustrate that image-assisted methods can improve the accuracy of conventional dietary assessment methods by adding eating occasion detail via pictures captured by an individual (dynamic images). All of the studies reduced underreporting with the help of images compared with results with traditional assessment methods. Studies with larger sample sizes are needed to better delineate attributes with regards to age of user, degree of error and cost.

Multiplanar lumbopelvic control in patients with low back pain: is multiplanar assessment better than single plane assessment in discriminating between patients and healthy controls?

Science.gov (United States)

Nelson-Wong, E; Gallant, P; Alexander, S; Dehmer, K; Ingvalson, S; McClenahan, B; Piatte, A; Poupore, K; Davis, A M

2016-02-01

Patients with low back pain (LBP) commonly have lumbopelvic control deficits. Lumbopelvic assessment during sagittal motion is incorporated into commonly used clinical examination algorithms for Treatment Based Classification. The purpose of this study was to investigate whether combined assessment of lumbopelvic control during sagittal and frontal plane motion discriminates between people with and without LBP better than single plane assessment alone. Nineteen patients with LBP and 18 healthy control participants volunteered for this study. The active straight leg raise (ASLR) and active hip abduction (AHAbd) tests were used to assess lumbopelvic control during sagittal and frontal plane motion, respectively. The tests were scored as positive or negative using published scoring criteria. Contingency tables were created for each test alone and for the combined tests (both positive/both negative) with presence/absence of LBP as the reference standard to calculate accuracy statistics of sensitivity (sn), specificity (sp), likelihood (+LR and -LR), and diagnostic odds ratios (OR). Active straight leg raise and AHAbd tests alone had sn of 0·63, 0·74, respectively, sp of 0·61, 0·50, respectively, and OR of 2·7, 2·8, respectively. The combined tests had sn = 0·89, sp = 0·60, and OR = 12·0. Forty percent of patients with LBP had control deficits in both planes of motion. The AHAbd and ALSR tests appear to have greater diagnostic discrimination when used in combination than when used independently. A percentage of patients with LBP had control deficits in both planes, while others demonstrated uniplanar deficits only. These findings highlight the importance of multiplanar assessment in patients with LBP.

Anatomic Illustrations of Cranial Ultrasound Images Obtained Through the Mastoid Fontanelle in Neonates

Energy Technology Data Exchange (ETDEWEB)

Kim, Bong Man; Lee, Young Seok [Dankook University Hospital, Cheonan (Korea, Republic of)

2011-09-15

Neonatal cranial sonography performed through the mastoid fontanelle is more useful to evaluate the peripheral structures at the convexity of the cerebral hemispheres and brainstem rather than that performed through the anterior fontanelle. The purpose of this study is to demonstrate the anatomy of the extracerebral CSF space and brainstem and to suggest appropriate scan planes for performing neonatal cranial sonography through the mastoid fontanelle using MRI and multiplanar reconstruction programs. A neonate with normal features on ultrasonography and good image quality on MRI, including the 3D-SPGR axial scans, was selected. We made the reconstructed MR images corresponding to the sonongraphic planes and the anatomic models of the neonatal cranial sonographic images by using axial MRI as the standard reference on the same screen. We demonstrated the sonographic images at the levels of the body of the caudate nucleus and lentiform nucleus, the head of the caudate nucleus and thalamus, the third ventricle and midbrain, and the midbrain and cerebellar vermis on the oblique axial scans. Four oblique coronal images at the levels of the periventricular white matter, basal ganglia, thalamus and tentorium were also obtained. We illustrated the anatomic atlas with including four oblique axial scans and four oblique coronal scans that corresponded to the neonatal cranial sonographic images through the mastoid fontanelle. We objectively analyzed the anatomy of the extracerebral CSF space and brainstem by using MRI and multiplanar reconstruction programs and we provided the standardized sonographic scan planes through the mastoid fontanelle. This study will be very helpful for evaluating the abnormalities of the peripheral structures at the convexity of the cerebral hemispheres and brainstem

Postoperative evaluation after anterior cruciate ligament reconstruction: Measurements and abnormalities on radiographic and CT imaging

Energy Technology Data Exchange (ETDEWEB)

Kim, Min Cheol; Choi, Yun Sun; KIm, Hyoung Seop; Choi, Nam Hong [Nowon Eulji Medical Center, Eulji University, Seoul (Korea, Republic of)

2016-11-15

Reconstruction of a ruptured anterior cruciate ligament (ACL) is a well-established procedure for repair of ACL injury. Despite improvement of surgical and rehabilitation techniques over the past decades, up to 25% of patients still fail to regain satisfactory function after an ACL reconstruction. With development of CT imaging techniques for reducing metal artifacts, multi-planar reconstruction, and three-dimensional reconstruction, early post-operative imaging is increasingly being used to provide immediate feedback to surgeons regarding tunnel positioning, fixation, and device placement. Early post-operative radiography and CT imaging are easy to perform and serve as the baseline examinations for future reference.

Rapid flow imaging method

International Nuclear Information System (INIS)

Pelc, N.J.; Spritzer, C.E.; Lee, J.N.

1988-01-01

A rapid, phase-contrast, MR imaging method of imaging flow has been implemented. The method, called VIGRE (velocity imaging with gradient recalled echoes), consists of two interleaved, narrow flip angle, gradient-recalled acquisitions. One is flow compensated while the second has a specified flow encoding (both peak velocity and direction) that causes signals to contain additional phase in proportion to velocity in the specified direction. Complex image data from the first acquisition are used as a phase reference for the second, yielding immunity from phase accumulation due to causes other than motion. Images with pixel values equal to MΔΘ where M is the magnitude of the flow compensated image and ΔΘ is the phase difference at the pixel, are produced. The magnitude weighting provides additional vessel contrast, suppresses background noise, maintains the flow direction information, and still allows quantitative data to be retrieved. The method has been validated with phantoms and is undergoing initial clinical evaluation. Early results are extremely encouraging

Terahertz composite imaging method

Institute of Scientific and Technical Information of China (English)

QIAO Xiaoli; REN Jiaojiao; ZHANG Dandan; CAO Guohua; LI Lijuan; ZHANG Xinming

2017-01-01

In order to improve the imaging quality of terahertz(THz) spectroscopy, Terahertz Composite Imaging Method(TCIM) is proposed. The traditional methods of improving THz spectroscopy image quality are mainly from the aspects of de-noising and image enhancement. TCIM breaks through this limitation. A set of images, reconstructed in a single data collection, can be utilized to construct two kinds of composite images. One algorithm, called Function Superposition Imaging Algorithm(FSIA), is to construct a new gray image utilizing multiple gray images through a certain function. The features of the Region Of Interest (ROI) are more obvious after operating, and it has capability of merging ROIs in multiple images. The other, called Multi-characteristics Pseudo-color Imaging Algorithm(McPcIA), is to construct a pseudo-color image by combining multiple reconstructed gray images in a single data collection. The features of ROI are enhanced by color differences. Two algorithms can not only improve the contrast of ROIs, but also increase the amount of information resulting in analysis convenience. The experimental results show that TCIM is a simple and effective tool for THz spectroscopy image analysis.

A method of image improvement in three-dimensional imaging

International Nuclear Information System (INIS)

Suto, Yasuzo; Huang, Tewen; Furuhata, Kentaro; Uchino, Masafumi.

1988-01-01

In general, image interpolation is required when the surface configurations of such structures as bones and organs are three-dimensionally constructed from the multi-sliced images obtained by CT. Image interpolation is a processing method whereby an artificial image is inserted between two adjacent slices to make spatial resolution equal to slice resolution in appearance. Such image interpolation makes it possible to increase the image quality of the constructed three-dimensional image. In our newly-developed algorithm, we have converted the presently and subsequently sliced images to distance images, and generated the interpolation images from these two distance images. As a result, compared with the previous method, three-dimensional images with better image quality have been constructed. (author)

MR imaging of prostate cancer

International Nuclear Information System (INIS)

Heuck, A.; Scheidler, J.; Sommer, B.; Graser, A.; Mueller-Lisse, U.G.; Massmann, J.

2003-01-01

Accurate diagnosis and staging of prostate cancer (PC) is developing into an important health care issue in light of the high incidence of PC and the improvements in stage-adapted therapy. The purpose of this paper is to provide an overview on the current role of MR imaging and MR spectroscopy in the diagnosis and staging of PC.Material and methods Pertinent literature was searched and evaluated to collect information on current clinical indications, study techniques, diagnostic value, and limitations of magnetic resonance imaging and spectroscopy. Major indications for MR imaging of patients with supected PC are to define tumor location before biopsy when clinical or TRUS findings are inconclusive, and to provide accurate staging of histologically proven PC to ascertain effective therapy. Current MR imaging techniques for the evaluation of PC include multiplanar high-resolution T2-weighted FSE and T1-weighted SE sequences using combined endorectal and phased-array coils. Using these techniques, the reported accuracy of MR imaging for the diagnosis of extracapsular tumor extension ranges between 82 and 88% with sensitivities between 80 and 95%, and specificities between 82 and 93%. Typical MR findings of PC in different stages of disease, as well as diagnostic problems, such as chronic prostatitis, biopsy-related hemorrhage and therapy-related changes of prostatic tissue are discussed. In addition, the current perspectives and limitations of MR spectroscopy in PC are summarized. Current MR imaging techniques provide important diagnostic information in the pretherapeutic workup of PC including a high staging accuracy, and is superior to TRUS. (orig.) [de

Prospective comparison of MR imaging (1.5 T) and CT detection of small intracranial metastases

International Nuclear Information System (INIS)

Dowd, C.F.; Dillon, W.P.; Laxer, K.; Norman, D.; Newton, T.H.

1987-01-01

Prior studies indicate lack of MR imaging sensitivity in the evaluation of intractable seizure patients. The authors reviewed MR imaging studies of 15 patients with intractable seizures. High-quality thin-section multiplanar images were obtained with electrocardiographic gating and/or flow compensation techniques and a 1.5-T General Electric Signa unit. Correlation with intracranial electro-encephalography (EEG), CT, and pathology was obtained in all patients. Abnormalities on MR imaging were detected in all but one patient. Pathology revealed MTS in 12 of 15 patients. Other entities included heterotopias and cavernous angiomas. The authors' study indicates that high-resolution, flow-compensated MR imaging is quite sensitive for localization of eleptogenic structural abnormalities and complements EEG

Head and neck imaging with MDCT

International Nuclear Information System (INIS)

Imhof, H.; Czerny, Chr.; Dirisamer, A.

2003-01-01

Multi-slice CT (MDCT) is rapidly becoming the new standard in radiological imaging. Although its advantages in cardiovascular, thoracic and abdominal imaging are evident, the extent of its usefulness for imaging the head and neck has yet to be clarified. Because of the shorter examination time motion artifacts are reduced, phonation-studies are possible. Due to the thin-slicing and nearly isotropic multiplanar reconstruction (MPR) examination in only one plane is necessary, saving both time and radiation exposure. The shorter examination requires the use of higher concentrated contrast medium (400 mg of iodine/ml). The use of such a contrast medium produces a higher degree of contrast enhancement and provides a 5-10% higher contrast between the surrounding normal and pathological tissue, but is more time critical. MPRs are easily done in any plane within seconds and enables also three-dimensional visualization, what helps in the use of minimal invasive therapy, training and teaching and provides a way of handling the hundreds of images acquired during scanning

Four-dimensional ultrasonography of the fetal heart with spatiotemporal image correlation.

Science.gov (United States)

Gonçalves, Luís F; Lee, Wesley; Chaiworapongsa, Tinnakorn; Espinoza, Jimmy; Schoen, Mary Lou; Falkensammer, Peter; Treadwell, Marjorie; Romero, Roberto

2003-12-01

This study was undertaken to describe a new technique for the examination of the fetal heart using four-dimensional ultrasonography with spatiotemporal image correlation (STIC). Volume data sets of the fetal heart were acquired with a new cardiac gating technique (STIC), which uses automated transverse and longitudinal sweeps of the anterior chest wall. These volumes were obtained from 69 fetuses: 35 normal, 16 with congenital anomalies not affecting the cardiovascular system, and 18 with cardiac abnormalities. Dynamic multiplanar slicing and surface rendering of cardiac structures were performed. To illustrate the STIC technique, two representative volumes from a normal fetus were compared with volumes obtained from fetuses with the following congenital heart anomalies: atrioventricular septal defect, tricuspid stenosis, tricuspid atresia, and interrupted inferior vena cava with abnormal venous drainage. Volume datasets obtained with a transverse sweep were utilized to demonstrate the cardiac chambers, moderator band, interatrial and interventricular septae, atrioventricular valves, pulmonary veins, and outflow tracts. With the use of a reference dot to navigate the four-chamber view, intracardiac structures could be simultaneously studied in three orthogonal planes. The same volume dataset was used for surface rendering of the atrioventricular valves. The aortic and ductal arches were best visualized when the original plane of acquisition was sagittal. Volumes could be interactively manipulated to simultaneously visualize both outflow tracts, in addition to the aortic and ductal arches. Novel views of specific structures were generated. For example, the location and extent of a ventricular septal defect was imaged in a sagittal view of the interventricular septum. Furthermore, surface-rendered images of the atrioventricular valves were employed to distinguish between normal and pathologic conditions. Representative video clips were posted on the Journal's Web

Diagnostic imaging of craniofacial trauma and fractures and their sequelae

International Nuclear Information System (INIS)

Buitrago-Tellez, C.H.; Kunz, C.

2001-01-01

The value and applications of the CT modalities are on the rise, particularly since the availability of spiral CT techniques, while conventional native diagnostics is increasingly used for special imaging purposes. Multiplanar spiral CT enables high-quality coronary 2D reconstructions which, in the acute phase, make redundant primary coronary imaging modalities. Exact knowledge of typical fracture patterns facilitates the analysis of images of the relevant facial areas. 3D reconstructions are indispensable in pin-pointed surgery planning, generation of stereolithographic models, and image-guided interventions for examination of post-traumatic deformities. Since a secondary correction only very rarely leads to restitutio ad integrum, it is necessary to detect the therapy-relevant injuries very early, during acute diagnostic imaging, in order to lay the basis for subsequent therapy and restoration of the craniofacial structures and functions. (orig./CB) [de

Color image definition evaluation method based on deep learning method

Science.gov (United States)

Liu, Di; Li, YingChun

2018-01-01

In order to evaluate different blurring levels of color image and improve the method of image definition evaluation, this paper proposed a method based on the depth learning framework and BP neural network classification model, and presents a non-reference color image clarity evaluation method. Firstly, using VGG16 net as the feature extractor to extract 4,096 dimensions features of the images, then the extracted features and labeled images are employed in BP neural network to train. And finally achieve the color image definition evaluation. The method in this paper are experimented by using images from the CSIQ database. The images are blurred at different levels. There are 4,000 images after the processing. Dividing the 4,000 images into three categories, each category represents a blur level. 300 out of 400 high-dimensional features are trained in VGG16 net and BP neural network, and the rest of 100 samples are tested. The experimental results show that the method can take full advantage of the learning and characterization capability of deep learning. Referring to the current shortcomings of the major existing image clarity evaluation methods, which manually design and extract features. The method in this paper can extract the images features automatically, and has got excellent image quality classification accuracy for the test data set. The accuracy rate is 96%. Moreover, the predicted quality levels of original color images are similar to the perception of the human visual system.

Imaging of head and neck tumors -- methods: CT, spiral-CT, multislice-spiral-CT

International Nuclear Information System (INIS)

Baum, Ulrich; Greess, Holger; Lell, Michael; Noemayr, Anton; Lenz, Martin

2000-01-01

Spiral-CT is standard for imaging neck tumors. In correspondence with other groups we routinely use spiral-CT with thin slices (3 mm), a pitch of 1.3-1.5 and an overlapping reconstruction increment (2-3 mm). In patients with dental fillings a short additional spiral parallel to the corpus of the mandible reduces artifacts behind the dental arches and improves the diagnostic value of CT. For the assessment of the base of the skull, the orbital floor, the palate and paranasal sinuses an additional examination in the coronal plane is helpful. Secondary coronal reconstructions of axial scans are helpful in the evaluation of the crossing of the midline by small tumors of the tongue base or palate. For an optimal vascular or tissue contrast a sufficient volume of contrast medium and a start delay greater than 70-80 s are necessary. In our opinion the best results can be achieved with a volume of 150 ml, a flow of 2.5 ml/s and a start delay of 80 s. Dynamic enhanced CT is only necessary in some special cases. There is clear indication for dynamic enhanced CT where a glomus tumor is suspected. Additional functional CT imaging during i-phonation and/or Valsalva's maneuver are of great importance to prove vocal cords mobility. Therefore, imaging during i-phonation is an elemental part of every thorough examination of the hypopharynx and larynx region. Multislice-spiral-CT allows almost isotropic imaging of the head and neck region and improves the assessment of tumor spread and lymph node metastases in arbitrary oblique planes. Thin structures (the base of the skull, the orbital floor, the hard palate) as well as the floor of the mouth can be evaluated sufficiently with multiplanar reformations. Usually, additional coronal scanning is not necessary with multislice-spiral-CT. Multislice-spiral-CT is especially advantageous in defining the critical relationships of tumor and lymph node metastases and for functional imaging of the hypopharynx and larynx not only in the

Role of magnetic resonance imaging in patient selection for uterine artery embolization

International Nuclear Information System (INIS)

Cura, M.; Cura, A.; Bugnone, A.

2006-01-01

Uterine fibroids are common tumors of the female pelvis. Uterine artery embolization (UAE) is an effective treatment of symptomatic uterine leiomyoma in the appropriate candidates, reducing or eliminating leiomyoma-related symptoms of bleeding, bulk, and/or pain. Magnetic resonance imaging (MRI) can be used to assess women with symptoms potentially attributable to uterine leiomyomas, and help to determine who is an appropriate candidate for UAE. Because of soft tissue characterization, multiplanar imaging capabilities, and enhancement, MR imaging not only accurately detects and characterizes uterine leiomyomas but also may predict who will benefit from the embolization. MRI ability to detect coexistent uterine or pelvic pathology may change the diagnosis and treatment management of patients being evaluated for UAE

Role of magnetic resonance imaging in patient selection for uterine artery embolization

Energy Technology Data Exchange (ETDEWEB)

Cura, M.; Cura, A.; Bugnone, A. [Univ. of Texas Health Science Center, San Antonio, TX (United States). Dept. of Radiology

2006-12-15

Uterine fibroids are common tumors of the female pelvis. Uterine artery embolization (UAE) is an effective treatment of symptomatic uterine leiomyoma in the appropriate candidates, reducing or eliminating leiomyoma-related symptoms of bleeding, bulk, and/or pain. Magnetic resonance imaging (MRI) can be used to assess women with symptoms potentially attributable to uterine leiomyomas, and help to determine who is an appropriate candidate for UAE. Because of soft tissue characterization, multiplanar imaging capabilities, and enhancement, MR imaging not only accurately detects and characterizes uterine leiomyomas but also may predict who will benefit from the embolization. MRI ability to detect coexistent uterine or pelvic pathology may change the diagnosis and treatment management of patients being evaluated for UAE.

Multislice helical CT (MSCT) for mid-facial trauma: optimization of parameters for scanning and reconstruction

International Nuclear Information System (INIS)

Dammert, S.; Funke, M.; Obernauer, S.; Grabbe, E.; Merten, H.A.

2002-01-01

Purpose: To determine the optimal scan parameters in multislice helical CT (MSCT) of the facial bone complex for both axial scanning and multiplanar reconstructions. Material and Methods: An anthropomorphic skull phantom was examined with a MSCT. Axial scans were performed with continuously increasing collimations (4 x 1.25 - 4 x 2.5 mm), tube current (20 - 200 mA) and table speeds (3.75 mm/rot. and 7.5 mm/rot.). Multiplanar reconstructions in coronal and parasagittal planes with different reconstruction increment and slice thickness were evaluated in terms of image noise, contour artifacts and visualisation of anatomical structures. Results: The best image quality was obtained with a collimation of 4 x 1.25 mm and a - table speed of 3.75 mm/rot. A reconstruction increment of 0.6 mm achieved the best time to image quality relation. With these parameters the bone structures were depicted in an optimal way without artifacts. The tube current could be reduced to 50 mA without significant loss of image quality. The optimized protocol was used for regular routine examinations in patients with facial trauma (n = 66). Conclusions: Low-dose MSCT using thin collimation, low table speed and small reconstruction increments provides excellent data for both axial images and multiplanar reconstructions in patients with facial trauma. An additional examination in coronal orientation is therefore no longer necessary. (orig.) [de

Neonatal imaging using an on-site small footprint MR scanner

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Merhar, Stephanie L. [Perinatal Institute, Division of Neonatology, Cincinnati Children' s Hospital Medical Center, Cincinnati, OH (United States); Tkach, Jean A.; Dumoulin, Charles L. [Cincinnati Children' s Hospital Medical Center, Imaging Research Center, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Woods, Jason C. [Cincinnati Children' s Hospital Medical Center, Imaging Research Center, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Division of Pulmonary Medicine, Cincinnati, OH (United States); South, Andrew P.; Wiland, Emily L. [Children' s Hospital Medical Center of Akron, Division of Neonatology, Akron, OH (United States); Rattan, Mantosh S.; Kline-Fath, Beth M. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

2017-07-15

With its soft-tissue definition, multiplanar capabilities and advanced imaging techniques, magnetic resonance imaging (MRI) for neonatal care can provide better understanding of pathology, allowing for improved care and counseling to families. However, MR imaging in neonates is often difficult due to patient instability and the complex support necessary for survival. In our institution, we have installed a small footprint magnet in the neonatal intensive care unit (NICU) to minimize patient risks and provide the ability to perform MR imaging safely in this population. With this system, we have been able to provide more information with regard to central nervous system disorders, abdominal pathology, and pulmonary and airway abnormalities, and have performed postmortem imaging as an alternative or supplement to pathological autopsy. In our experience, an MR scanner situated within the NICU has allowed for safer and more expedited imaging of this vulnerable population. (orig.)

Neonatal imaging using an on-site small footprint MR scanner

International Nuclear Information System (INIS)

Merhar, Stephanie L.; Tkach, Jean A.; Dumoulin, Charles L.; Woods, Jason C.; South, Andrew P.; Wiland, Emily L.; Rattan, Mantosh S.; Kline-Fath, Beth M.

2017-01-01

With its soft-tissue definition, multiplanar capabilities and advanced imaging techniques, magnetic resonance imaging (MRI) for neonatal care can provide better understanding of pathology, allowing for improved care and counseling to families. However, MR imaging in neonates is often difficult due to patient instability and the complex support necessary for survival. In our institution, we have installed a small footprint magnet in the neonatal intensive care unit (NICU) to minimize patient risks and provide the ability to perform MR imaging safely in this population. With this system, we have been able to provide more information with regard to central nervous system disorders, abdominal pathology, and pulmonary and airway abnormalities, and have performed postmortem imaging as an alternative or supplement to pathological autopsy. In our experience, an MR scanner situated within the NICU has allowed for safer and more expedited imaging of this vulnerable population. (orig.)

Magnetic Resonance Imaging versus Computed Tomography and Different Imaging Modalities in Evaluation of Sinonasal Neoplasms Diagnosed by Histopathology

Directory of Open Access Journals (Sweden)

Mohammed A. Gomaa

2013-01-01

Full Text Available Objective The study purpose was to detect the value of magnetic resonance imaging (MRI compared to computed tomography (CT and different imaging modalities as conventional radiology in evaluation of sinonasal neoplasms diagnosed by Histopathology. Methods Thirty patients (16 males and 14 females were complaining of symptoms related to sinonasal tract. After thorough clinical and local examination, the patients were subjected to the following: conventional radiography, CT, MRI, and histopathological examination. Results The nasal cavity was the most commonly involved site with sinonasal malignancies followed by the maxillary sinuses. The least commonly affected site was the frontal sinuses. Benign sinonasal tumors were present in 14 cases. The most common benign lesion was juvenile nasopharyngeal angiofibroma (6 cases, followed by inverted papilloma (3 cases. While malignant sinonasal tumors were present in 16 cases, squamous cell carcinoma was present in 5 cases, and undifferentiated carcinoma, in 3 cases. Lymphoepithelioma and non-Hodgkin lymphomas were present in 2 cases each, while adenocarcinoma, chondrosarcoma, adenoid cystic carcinoma, and rhabdomyosarcoma were present in 1 case each. Conclusion MRI with its superior soft tissue contrast and multiplanar capability is superior to CT in pretreatment evaluation of primary malignant tumors of sinonasal cavity.

Magnetic resonance imaging of the elbow. Part II: Abnormalities of the ligaments, tendons, and nerves

Energy Technology Data Exchange (ETDEWEB)

Kijowski, Richard; Tuite, Michael; Sanford, Matthew [University of Wisconsin Hospital, Department of Radiology, Madison, WI (United States)

2005-01-01

Part II of this comprehensive review on magnetic resonance imaging of the elbow discusses the role of magnetic resonance imaging in evaluating patients with abnormalities of the ligaments, tendons, and nerves of the elbow. Magnetic resonance imaging can yield high-quality multiplanar images which are useful in evaluating the soft tissue structures of the elbow. Magnetic resonance imaging can detect tears of the ulnar collateral ligament and lateral collateral ligament of the elbow with high sensitivity and specificity. Magnetic resonance imaging can determine the extent of tendon pathology in patients with medial epicondylitis and lateral epicondylitis. Magnetic resonance imaging can detect tears of the biceps tendon and triceps tendon and can distinguishing between partial and complete tendon rupture. Magnetic resonance imaging is also helpful in evaluating patients with nerve disorders at the elbow. (orig.)

Liver imaging with MDCT and high concentration contrast media

International Nuclear Information System (INIS)

Spielmann, Audrey L.

2003-01-01

Liver imaging has advanced greatly over the last 10 years with helical CT capability and more recently the addition of multidetector-row CT (MDCT). Multidetector CT technology facilitates imaging at faster speeds with improved image quality and less breathing artifact [Abdom. Imaging 25 (2000) 643]. Exquisite three-dimensional data sets can be obtained with thin collimation providing improved lesion detection, multiplanar imaging, and the ability to perform CT angiography of the liver and mesenteric vessels. New challenges arise with this advance in technology including safety considerations. The radiation dose to the patient has increased with MDCT and this is compounded by the ability to perform multi-phase liver imaging. Furthermore, issues of contrast media administration require reconsideration including optimal timing and rate of administration, the total volume of contrast needed and the ideal iodine concentration of the contrast media. Recently, the use of high concentration contrast media (HCCM) has been explored and study results to date will be reviewed

Post-therapeutic imaging findings

Energy Technology Data Exchange (ETDEWEB)

Pollice, Saverio, E-mail: saveriopollice@hotmail.it [Department of Radiology and Neuroradiology, “L. Bonomo Hospital”, 76123 Andria, BT (Italy); Muto, Mario, E-mail: mutomar@tiscali.it [Department of Neuroradiology, “Cardarelli Hospital”, Naples (Italy); Scarabino, Tommaso, E-mail: tscarabino@hotmail.com [Department of Radiology and Neuroradiology, “L. Bonomo Hospital”, 76123 Andria, BT (Italy)

2015-05-15

Highlights: • This study is the result of collaboration between neuroradiologists and neurosurgeons. • Comparison between neuroimaging techniques to better evaluate the complications after treatment of the spin. • Evaluation of the imaging features of complications and definition of follow-up. - Abstract: Any surgical approach modifies the normal anatomical and functional arrangement of the segmental spine which is aimed, therefore image interpretation cannot ignore a correct set of knowledge in the field of anatomy, pathophysiology, drug compliance, interventional radiology and surgery. Neuroradiological imaging has an important role before surgery to direct the surgeon or interventional radiologist during the operation, both in post-surgery, where imaging examination can rightly evaluate properties and effects of the treatment and can detect potential complications as infections, abscess, bleeding, exuberant scar, mobilization and rupture of devices. The available methods of imaging are the X-rays (XR) made at least in two projections, Computed Tomography (CT) with MPR (multiplanar) and VR (volume rendering) reconstruction, and Magnetic Resonance (MR), often performed before and after contrast media injection. Imaging assessment of spine after surgery is complex and depends upon several factors, including surgical procedures and disease for which it was performed; biomechanical of the underlying cortical and cancellous bone findings; conditions of muscles, intervertebral disk and ligaments; time since surgery procedures; duration and nature of the post-surgical syndrome. Depending upon several factors, one or a combination of complementary imaging modalities (X-rays, Computed Tomography, Magnetic Resonance) may be required to evaluate effectiveness of the treatment; to demonstrate any clinically relevant abnormality at the treated region and adjacent structures (complications such as inflammation, abscesses, bleeding and misplacement of the device); to

Post-therapeutic imaging findings

International Nuclear Information System (INIS)

Pollice, Saverio; Muto, Mario; Scarabino, Tommaso

2015-01-01

Highlights: • This study is the result of collaboration between neuroradiologists and neurosurgeons. • Comparison between neuroimaging techniques to better evaluate the complications after treatment of the spin. • Evaluation of the imaging features of complications and definition of follow-up. - Abstract: Any surgical approach modifies the normal anatomical and functional arrangement of the segmental spine which is aimed, therefore image interpretation cannot ignore a correct set of knowledge in the field of anatomy, pathophysiology, drug compliance, interventional radiology and surgery. Neuroradiological imaging has an important role before surgery to direct the surgeon or interventional radiologist during the operation, both in post-surgery, where imaging examination can rightly evaluate properties and effects of the treatment and can detect potential complications as infections, abscess, bleeding, exuberant scar, mobilization and rupture of devices. The available methods of imaging are the X-rays (XR) made at least in two projections, Computed Tomography (CT) with MPR (multiplanar) and VR (volume rendering) reconstruction, and Magnetic Resonance (MR), often performed before and after contrast media injection. Imaging assessment of spine after surgery is complex and depends upon several factors, including surgical procedures and disease for which it was performed; biomechanical of the underlying cortical and cancellous bone findings; conditions of muscles, intervertebral disk and ligaments; time since surgery procedures; duration and nature of the post-surgical syndrome. Depending upon several factors, one or a combination of complementary imaging modalities (X-rays, Computed Tomography, Magnetic Resonance) may be required to evaluate effectiveness of the treatment; to demonstrate any clinically relevant abnormality at the treated region and adjacent structures (complications such as inflammation, abscesses, bleeding and misplacement of the device); to

Three-dimentional imaging of dentomaxillofacial region using electron beam tomography

International Nuclear Information System (INIS)

Tanaka, Takemasa; Kanda, Shigenobu; Muranaka, Toru

1998-01-01

Authors reported their results of the 3-D imaging of dentomaxillofacial region mainly for jaw deformity with electron beam tomography (EBT). The EBT apparatus used was Imatron C-100 (Imatron Corp.), with which, using bremsstrahlung radiation generated from the electron beam, CT is possible with rapid scanning rate at <0.1 sec. Imaging was done with those conditions as tube voltage: 130 kV, current: 610 mA, scanning rate: 0.1 sec/slice whose thickness was 1.5 mm, feeding rate: 1.5 mm and number of slices: 40-170. Patients were 15 cases with jaw deformity. Data were processed for 3-D image by Scribe Imaging Workstation (Multi-dimensional Imaging Inc.) which giving surface rendering and further by Power Macintosh 8500 (Apple Computer Inc.) with VoxBlast 1.1.0 (VayTec Inc.) software which giving volume rendering or with Image 1.60 (NIH) which allowing multi-planar reconstruction and re-analog projection. These actual images were presented in the report. (K.H.)

Methods for evaluating imaging methods of limited reproducibility

International Nuclear Information System (INIS)

Krummenauer, F.

2005-01-01

Just like new drugs, new or modified imaging methods must be subjected to objective clinical tests, including tests on humans. In this, it must be ensured that the principle of Good Clinical Practice (GCP) are followed with regard to medical, administrative and methodical quality. Innovative methods fo clinical epidemiology and medical biometry should be applied from the planning stage to the final statistical evaluation. The author presents established and new methods for planning, evaluation and reporting of clinical tests of diagnostic methods, and especially imaging methods, in clinical medicine and illustrates these by means of current research projects in the various medical disciplines. The strategies presented are summarized in a recommendation based on the concept of phases I - IV of clinical drug testing in order to enable standardisation of the clinical evaluation of imaging methods. (orig.)

MR imaging of the finger tendons: Normal anatomy and commonly encountered pathology

International Nuclear Information System (INIS)

Ragheb, Dina; Stanley, Anthony; Gentili, Amilcare; Hughes, Tudor; Chung, Christine B.

2005-01-01

MR imaging has emerged as a powerful tool in the evaluation of soft tissue structures such as the tendons of the hand and finger due to its excellent soft tissue contrast and multiplanar imaging capabilities. In the finger and hand, perhaps more than in any other location in the body, a detailed and intimate understanding of anatomy is crucial for lesion localization, directing clinical management and predicting long-term prognosis. These issues are of paramount importance to both the clinician and imager, both faced with the challenge of the complex anatomy and pathology associated with these delicate structures. The anatomy of the finger including intrinsic and extrinsic muscles, retinacular structures, and tendons will be discussed. The MR imaging features of common lesions of the tendons of the hand and finger will be reviewed

Magnetic resonance imaging of epidermoid, including diffusion weighted images and an atypical case

International Nuclear Information System (INIS)

Takahashi, Shoki; Higano, Shuichi; Kurihara, Noriko

1994-01-01

In order to study the role of magnetic resonance imaging (MRI) in diagnosing intracranial epidermoid, we evaluated the MRI findings on five cases with such tumor, all of which were surgically verified. In addition to standard spin-echo (SE) images obtained in all cases, diffusion-weighted images were acquired in two patients. In four patients, the tumor revealed to be almost isointense relative to cerebrospinal fluid (CSF) on both T 1 -and T 2 -weighted images, while it tended to show slightly hyperintense to CSF on proton-density-weighted images; thus, based on the signal intensity on standard SE images the distinction between epidermoid and arachnoid cyst may be difficult. Furthermore, the presence of the tumor which has a tendency to grow in and along the subarachnoid space causing relatively minimal mass effect may be overlooked. Diffusion-weighted images were shown to have advantages in such cases by demonstrating the tumor unequivocally as a mass of high signal, and differentiating it from arachnoid cysts. In the remaining patient, its appearance was atypical, showing bright signal on both T 1 -and T 2 -weighted images. In conclusion free of bone artifacts, multiplanar MRI with additional diffusion-weighted images provides a clear demonstration of epidermoid, and its differentiation from arachnoid cyst, thus obviating the need for CT cisternography. (author)

Advances in medical imaging for the diagnosis and management of common genitourinary cancers.

Science.gov (United States)

Bagheri, Mohammad H; Ahlman, Mark A; Lindenberg, Liza; Turkbey, Baris; Lin, Jeffrey; Cahid Civelek, Ali; Malayeri, Ashkan A; Agarwal, Piyush K; Choyke, Peter L; Folio, Les R; Apolo, Andrea B

2017-07-01

Medical imaging of the 3 most common genitourinary (GU) cancers-prostate adenocarcinoma, renal cell carcinoma, and urothelial carcinoma of the bladder-has evolved significantly during the last decades. The most commonly used imaging modalities for the diagnosis, staging, and follow-up of GU cancers are computed tomography, magnetic resonance imaging (MRI), and positron emission tomography (PET). Multiplanar multidetector computed tomography and multiparametric MRI with diffusion-weighted imaging are the main imaging modalities for renal cell carcinoma and urothelial carcinoma, and although multiparametric MRI is rapidly becoming the main imaging tool in the evaluation of prostate adenocarcinoma, biopsy is still required for diagnosis. Functional and molecular imaging using 18-fluorodeoxyglucose-PET and sodium fluoride-PET are essential for the diagnosis, and especially follow-up, of metastatic GU tumors. This review provides an overview of the latest advances in the imaging of these 3 major GU cancers. Published by Elsevier Inc.

Image splitting and remapping method for radiological image compression

Science.gov (United States)

Lo, Shih-Chung B.; Shen, Ellen L.; Mun, Seong K.

1990-07-01

A new decomposition method using image splitting and gray-level remapping has been proposed for image compression, particularly for images with high contrast resolution. The effects of this method are especially evident in our radiological image compression study. In our experiments, we tested the impact of this decomposition method on image compression by employing it with two coding techniques on a set of clinically used CT images and several laser film digitized chest radiographs. One of the compression techniques used was full-frame bit-allocation in the discrete cosine transform domain, which has been proven to be an effective technique for radiological image compression. The other compression technique used was vector quantization with pruned tree-structured encoding, which through recent research has also been found to produce a low mean-square-error and a high compression ratio. The parameters we used in this study were mean-square-error and the bit rate required for the compressed file. In addition to these parameters, the difference between the original and reconstructed images will be presented so that the specific artifacts generated by both techniques can be discerned by visual perception.

Methods of digital image processing

International Nuclear Information System (INIS)

Doeler, W.

1985-01-01

Increasing use of computerized methods for diagnostical imaging of radiological problems will open up a wide field of applications for digital image processing. The requirements set by routine diagnostics in medical radiology point to picture data storage and documentation and communication as the main points of interest for application of digital image processing. As to the purely radiological problems, the value of digital image processing is to be sought in the improved interpretability of the image information in those cases where the expert's experience and image interpretation by human visual capacities do not suffice. There are many other domains of imaging in medical physics where digital image processing and evaluation is very useful. The paper reviews the various methods available for a variety of problem solutions, and explains the hardware available for the tasks discussed. (orig.) [de

Image registration method for medical image sequences

Science.gov (United States)

Gee, Timothy F.; Goddard, James S.

2013-03-26

Image registration of low contrast image sequences is provided. In one aspect, a desired region of an image is automatically segmented and only the desired region is registered. Active contours and adaptive thresholding of intensity or edge information may be used to segment the desired regions. A transform function is defined to register the segmented region, and sub-pixel information may be determined using one or more interpolation methods.

[Imaging of pelvic organ prolapse].

Science.gov (United States)

Lapray, Jean-François

2013-01-01

Colpocystodefecography (CCD) and dynamic MRI with defecography (MRId) allow an alternation between filling and emptying the hollow organs and the maximum abdominal strain offered by the defecation. When applied in imaging these two principles reveal the masked or underestimated prolapses at the time of the physical examination. A rigorous application of the technique guarantees almost equivalent results from the two examinations. The CCD provides voiding views and improved analysis of the anorectal pathology (intussusception, anismus) but involves radiation and a more invasive examination. MRId has the advantage of providing continuous visibility of the peritoneal compartment, and a multiplanar representation, enabling an examination of the morphology of the pelvic organs and of the supporting structures, with the disadvantage of still necessitating a supine examination, resulting sometimes in an incomplete or impossible evacuation. The normal and abnormal results (cystoptosis, vaginal vault prolapse, enterocele, anorectal intussuception, rectocele, descending perineum, urinary and fecal incontinence) and the respective advantages and limits of the various imaging methods are detailed. Dynamic perineal and introital ultrasound remains more limited in the appreciation of posterior colpoceles and especially in anorectal disorders, than CCD or MRId. Endoanal ultrasound is the first line morphological evaluation of the anal sphincter. Transvaginal and introital ultrasound can detect some complications of suburethral tapes and meshes. Morphological and dynamic imaging are essential complementary tools to the physical examination, especially when a precise anatomic assessment is required to understand the functional complaint or when a reintervention is needed.

Twin-Foucault imaging method

Science.gov (United States)

Harada, Ken

2012-02-01

A method of Lorentz electron microscopy, which enables observation two Foucault images simultaneously by using an electron biprism instead of an objective aperture, was developed. The electron biprism is installed between two electron beams deflected by 180° magnetic domains. Potential applied to the biprism deflects the two electron beams further, and two Foucault images with reversed contrast are then obtained in one visual field. The twin Foucault images are able to extract the magnetic domain structures and to reconstruct an ordinary electron micrograph. The developed Foucault method was demonstrated with a 180° domain structure of manganite La0.825Sr0.175MnO3.

Non-invasive coronary angiography with multislice computed tomography. Technology, methods, preliminary experience and prospects.

Science.gov (United States)

Traversi, Egidio; Bertoli, Giuseppe; Barazzoni, Giancarlo; Baldi, Maurizia; Tramarin, Roberto

2004-02-01

The recent technical developments in multislice computed tomography (MSCT), with ECG retro-gated image reconstruction, have elicited great interest in the possibility of accurate non-invasive imaging of the coronary arteries. The latest generation of MSCT systems with 8-16 rows of detectors permits acquisition of the whole cardiac volume during a single 15-20 s breath-hold with a submillimetric definition of the images and an outstanding signal-to-noise ratio. Thus the race which, between MSCT, electron beam computed tomography and cardiac magnetic resonance imaging, can best provide routine and reliable imaging of the coronary arteries in clinical practice has recommenced. Currently available MSCT systems offer different options for both cardiac image acquisition and reconstruction, including multiplanar and curved multiplanar reconstruction, three-dimensional volume rendering, maximum intensity projection, and virtual angioscopy. In our preliminary experience including 176 patients suffering from known or suspected coronary artery disease, MSCT was feasible in 161 (91.5%) and showed a sensitivity of 80.4% and a specificity of 80.3%, with respect to standard coronary angiography, in detecting critical stenosis in coronary arteries and artery or venous bypass grafts. These results correspond to a positive predictive value of 58.6% and a negative predictive value of 92.2%. The true role that MSCT is likely to play in the future in non-invasive coronary imaging is still to be defined. Nevertheless, the huge amount of data obtainable by MSCT along with the rapid technological advances, shorter acquisition times and reconstruction algorithm developments will make the technique stronger, and possible applications are expected not only for non-invasive coronary angiography, but also for cardiac function and myocardial perfusion evaluation, as an all-in-one examination.

Image quality analysis to reduce dental artifacts in head and neck imaging with dual-source computed tomography

Energy Technology Data Exchange (ETDEWEB)

Ketelsen, D.; Werner, M.K.; Thomas, C.; Tsiflikas, I.; Reimann, A.; Claussen, C.D.; Heuschmid, M. [Tuebingen Univ. (Germany). Abt. fuer Diagnostische und Interventionelle Radiologie; Koitschev, A. [Tuebingen Univ. (Germany). Abt. fuer Hals-Nasen-Ohrenheilkunde

2009-01-15

Purpose: Important oropharyngeal structures can be superimposed by metallic artifacts due to dental implants. The aim of this study was to compare the image quality of multiplanar reconstructions and an angulated spiral in dual-source computed tomography (DSCT) of the neck. Materials and Methods: Sixty-two patients were included for neck imaging with DSCT. MPRs from an axial dataset and an additional short spiral parallel to the mouth floor were acquired. Leading anatomical structures were then evaluated with respect to the extent to which they were affected by dental artifacts using a visual scale, ranging from 1 (least artifacts) to 4 (most artifacts). Results: In MPR, 87.1 % of anatomical structures had significant artifacts (3.12 {+-} 0.86), while in angulated slices leading anatomical structures of the oropharynx showed negligible artifacts (1.28 {+-} 0.46). The diagnostic growth due to primarily angulated slices concerning artifact severity was significant (p < 0.01). Conclusion: MPRs are not capable of reducing dental artifacts sufficiently. In patients with dental artifacts overlying the anatomical structures of the oropharynx, an additional short angulated spiral parallel to the floor of the mouth is recommended and should be applied for daily routine. As a result of the static gantry design of DSCT, the use of a flexible head holder is essential. (orig.)

Extra-adrenal pheochromocytoma in pregnancy: ultrasonography and magnetic resonance imaging findings

Energy Technology Data Exchange (ETDEWEB)

Carson, B.J.W.; Johnston, M.A.; Iwaniuk, G.

1995-04-01

The case of a 24-year-old woman with extra-adrenal pheochromocytoma during pregnancy was described. Initial ultrasonography (US) at 27 weeks gestational age failed to show the pheochromocytoma, which was subsequently found by US at 35 weeks gestational age. Magnetic resonance imaging (MRI) provided diagnostic confirmation, as well as important information used by the obstetrician and the surgeon in operative planning. MRI proved to be ideally suited to investigation of extra-adrenal pheochromocytomas in pregnancy because it does not use ionizing radiation, and it has multiplanar capability and high contrast resolution. In the case described, the lesion was demonstrated with all MRI pulse sequences, but was best visualized with turbo spin-echo T2-weighted imaging, as well as with fat-suppressed imaging. 7 refs., 2 figs.

Optimal pulse sequence for ferumoxides-enhanced MR imaging used in the detection of hepatocellular carcinoma: a comparative study using seven pulse sequences

International Nuclear Information System (INIS)

Kim, Seung Hoon; Choi, Dongil; Lim, Jae Hoon; Lee, Won Jae; Jang, Hyun Jung; Lim, Kyo Keun; Lee, Soon Jin; Cho, Jae Min; Kim, Seung Kwon; Kim, Gab Chul

2002-01-01

To identify the optimal pulse sequence for ferumoxides-enhanced magnetic resonance (MR) imaging in the detection of hepatocelluar carcinomas (HCCs). Sixteen patients with 25 HCCs underwent MR imaging following intravenous infusion of ferumoxides. All MR studies were performed on a 1.5-T MR system, using a phased-array coil. Ferumoxides (Feridex IV) at a dose of 15 μmol/Kg was slowly infused intravenously, and axial images of seven sequences were obtained 30 minutes after the end of infusion. The MR protocol included fast spin-echo (FSE) with two echo times (TR3333-8571/TE18 and 90-117), singleshot FSE (SSFSE) with two echo times (TR∞/TE39 and 98), T2-weighted gradient-recalled acquisition in the steady state (GRASS) (TR216/TE20), T2-weighted fast multiplanar GRASS (FMPGR) (TR130/TE8.4-9.5), and T2-weighted fast multiplanar spoiled GRASS (FMPSPGR) (TR130/TE8.4-9.5). Contrast-to-noise ratios (CNRs) of HCCs determined during the imaging sequences formed the basis of quantitative analysis, and images were qualitatively assessed in terms of lesion conspicuity and image artifacts. The diagnostic accuracy of all sequences was assessed using receiver operating characteristic (ROC) analysis. Quantitative analysis revealed that the CNRs of T2-weighted FMPGR and T2-weighted FMPSPGR were significantly higher than those of the other sequences, while qualitative analysis showed that image artifacts were prominent at T2-weighted GRASS imaging. Lesion conspicuity was statistically significantly less clear at SSFSE imaging. In term of lesion detection, T-weighted FMPGR, T2- weighted FMPSPGR, and proton density FSE imaging were statistically superior to the others. T2-weighted FMPGR, T2- weighted FMPSPGR, and proton density FSE appear to be the optimal pulse sequences for ferumoxidesenhanced MR imaging in the detection of HCCs

CT imaging and histopathological features of renal epithelioid angiomyolipomas

International Nuclear Information System (INIS)

Cui, L.; Zhang, J.-G.; Hu, X.-Y.; Fang, X.-M.; Lerner, A.; Yao, X.-J.; Zhu, Z.-M.

2012-01-01

Aim: To describe computed tomography (CT) imaging and histopathological manifestations of renal epithelioid angiomyolipomas (EAMLs) for better understanding and cognition in the diagnosis of this new category of renal tumours. Materials and methods: Clinical data and CT images from 10 cases of EAML were retrospectively analysed. All patients underwent CT with and without contrast medium administration, with multiplanar reconstruction (MPR) when needed. Results: Plain CT manifestations of EAMLs were a higher density of mass (10–25 HU) than renal parenchyma, bulging contour of the involved kidney, absence of fat, distinct edges without a lobulate appearance. Contrast-enhanced CT features were markedly heterogeneous enhancement (from rapid wash-in to slow wash-out), large tumour size without lobular appearance, complete capsule with distinct margins and frequent mild necrotic areas. Histopathological features were epithelioid cells with eosinophilic cytoplasm, large and deeply stained nuclei, and dense arrangement of tumour cells with patchy necrosis; diffuse sheets of epithelioid cells were positive for HMB-45 (melanoma-associated antigen) and negative for epithelial membrane antigen (EMA) staining. Conclusion: Multiple specific CT features correlated well with the histopathology and may play an important role in the primary diagnosis of EAMLs.

Methods in Astronomical Image Processing

Science.gov (United States)

Jörsäter, S.

A Brief Introductory Note History of Astronomical Imaging Astronomical Image Data Images in Various Formats Digitized Image Data Digital Image Data Philosophy of Astronomical Image Processing Properties of Digital Astronomical Images Human Image Processing Astronomical vs. Computer Science Image Processing Basic Tools of Astronomical Image Processing Display Applications Calibration of Intensity Scales Calibration of Length Scales Image Re-shaping Feature Enhancement Noise Suppression Noise and Error Analysis Image Processing Packages: Design of AIPS and MIDAS AIPS MIDAS Reduction of CCD Data Bias Subtraction Clipping Preflash Subtraction Dark Subtraction Flat Fielding Sky Subtraction Extinction Correction Deconvolution Methods Rebinning/Combining Summary and Prospects for the Future

Evaluation of the anterior ethmoidal artery by 3D dual volume rotational digital subtraction angiography and native multidetector CT with multiplanar reformations. Initial findings.

Science.gov (United States)

Pandolfo, Ignazio; Vinci, Sergio; Salamone, Ignazio; Granata, Francesca; Mazziotti, Silvio

2007-06-01

Our purpose is to codify the anterior ethmoidal artery (AEA) course and its relationship with adjacent structures. Twenty patients with cerebrovascular disease underwent selective internal carotid dual volume angiography. Fusion of the vascular and bony images was obtained successively on a second console. MDCT of the cranium was performed in all patients. To identify the AEA course, multiplanar CT reformations were obtained. In all cases the entry-point of AEA and its course were identified by means of dual volume angiography. The information was confirmed by MDCT. In a second phase, we studied another 78 patients affected by inflammatory disease and polyposis only by means of MDCT, in order to confirm the previous data obtained by comparison between angiography and MDCT. In this second phase, 110/156 vessels were indirectly detected by means of visualization of the ethmoidal entry point. In the remaining cases, AEA was directly shown due to integrity of the thin ethmoidal bone lamellae or bony canal. Dual volume angiography is essential to identify the course of the AEA (standard of reference for the interpretation of CT). In patients with benign rhinosinusal pathology, where invasivity techniques are not justified, MPR reconstructions were of pivotal importance in the evaluation of the course of the artery with particular reference to its relationship with the frontal recess.

Imaging system for creating 3D block-face cryo-images of whole mice

Science.gov (United States)

Roy, Debashish; Breen, Michael; Salvado, Olivier; Heinzel, Meredith; McKinley, Eliot; Wilson, David

2006-03-01

We developed a cryomicrotome/imaging system that provides high resolution, high sensitivity block-face images of whole mice or excised organs, and applied it to a variety of biological applications. With this cryo-imaging system, we sectioned cryo-preserved tissues at 2-40 μm thickness and acquired high resolution brightfield and fluorescence images with microscopic in-plane resolution (as good as 1.2 μm). Brightfield images of normal and pathological anatomy show exquisite detail, especially in the abdominal cavity. Multi-planar reformatting and 3D renderings allow one to interrogate 3D structures. In this report, we present brightfield images of mouse anatomy, as well as 3D renderings of organs. For BPK mice model of polycystic kidney disease, we compared brightfield cryo-images and kidney volumes to MRI. The color images provided greater contrast and resolution of cysts as compared to in vivo MRI. We note that color cryo-images are closer to what a researcher sees in dissection, making it easier for them to interpret image data. The combination of field of view, depth of field, ultra high resolution and color/fluorescence contrast enables cryo-image volumes to provide details that cannot be found through in vivo imaging or other ex vivo optical imaging approaches. We believe that this novel imaging system will have applications that include identification of mouse phenotypes, characterization of diseases like blood vessel disease, kidney disease, and cancer, assessment of drug and gene therapy delivery and efficacy and validation of other imaging modalities.

Digital image processing mathematical and computational methods

CERN Document Server

Blackledge, J M

2005-01-01

This authoritative text (the second part of a complete MSc course) provides mathematical methods required to describe images, image formation and different imaging systems, coupled with the principle techniques used for processing digital images. It is based on a course for postgraduates reading physics, electronic engineering, telecommunications engineering, information technology and computer science. This book relates the methods of processing and interpreting digital images to the 'physics' of imaging systems. Case studies reinforce the methods discussed, with examples of current research

An Image Registration Method for Colposcopic Images

Directory of Open Access Journals (Sweden)

Efrén Mezura-Montes

2013-01-01

sequence and a division of such image into small windows. A search process is then carried out to find the window with the highest affinity in each image of the sequence and replace it with the window in the reference image. The affinity value is based on polynomial approximation of the time series computed and the search is bounded by a search radius which defines the neighborhood of each window. The proposed approach is tested in ten 310-frame real cases in two experiments: the first one to determine the best values for the window size and the search radius and the second one to compare the best obtained results with respect to four registration methods found in the specialized literature. The obtained results show a robust and competitive performance of the proposed approach with a significant lower time with respect to the compared methods.

Comparison of different reconstruction algorithms for three-dimensional ultrasound imaging in a neurosurgical setting.

Science.gov (United States)

Miller, D; Lippert, C; Vollmer, F; Bozinov, O; Benes, L; Schulte, D M; Sure, U

2012-09-01

Freehand three-dimensional ultrasound imaging (3D-US) is increasingly used in image-guided surgery. During image acquisition, a set of B-scans is acquired that is distributed in a non-parallel manner over the area of interest. Reconstructing these images into a regular array allows 3D visualization. However, the reconstruction process may introduce artefacts and may therefore reduce image quality. The aim of the study is to compare different algorithms with respect to image quality and diagnostic value for image guidance in neurosurgery. 3D-US data sets were acquired during surgery of various intracerebral lesions using an integrated ultrasound-navigation device. They were stored for post-hoc evaluation. Five different reconstruction algorithms, a standard multiplanar reconstruction with interpolation (MPR), a pixel nearest neighbour method (PNN), a voxel nearest neighbour method (VNN) and two voxel based distance-weighted algorithms (VNN2 and DW) were tested with respect to image quality and artefact formation. The capability of the algorithm to fill gaps within the sample volume was investigated and a clinical evaluation with respect to the diagnostic value of the reconstructed images was performed. MPR was significantly worse than the other algorithms in filling gaps. In an image subtraction test, VNN2 and DW reliably reconstructed images even if large amounts of data were missing. However, the quality of the reconstruction improved, if data acquisition was performed in a structured manner. When evaluating the diagnostic value of reconstructed axial, sagittal and coronal views, VNN2 and DW were judged to be significantly better than MPR and VNN. VNN2 and DW could be identified as robust algorithms that generate reconstructed US images with a high diagnostic value. These algorithms improve the utility and reliability of 3D-US imaging during intraoperative navigation. Copyright © 2012 John Wiley & Sons, Ltd.

Improved radionuclide bone imaging agent injection needle withdrawal method can improve image quality

International Nuclear Information System (INIS)

Qin Yongmei; Wang Laihao; Zhao Lihua; Guo Xiaogang; Kong Qingfeng

2009-01-01

Objective: To investigate the improvement of radionuclide bone imaging agent injection needle withdrawal method on whole body bone scan image quality. Methods: Elbow vein injection syringe needle directly into the bone imaging agent in the routine group of 117 cases, with a cotton swab needle injection method for the rapid pull out the needle puncture point pressing, pressing moment. Improvement of 117 cases of needle injection method to put two needles into the skin swabs and blood vessels, pull out the needle while pressing two or more entry point 5min. After 2 hours underwent whole body bone SPECT imaging plane. Results: The conventional group at the injection site imaging agents uptake rate was 16.24%, improved group was 2.56%. Conclusion: The modified bone imaging agent injection needle withdrawal method, injection-site imaging agent uptake were significantly decreased whole body bone imaging can improve image quality. (authors)

Based on airborne multi-array butting for IRFPA staring imagery

Science.gov (United States)

Mao, Minjun; Xiao, Gonghai; Lin, Yancheng; Xie, Feng; Shu, Rong

2010-10-01

Because infrared system detects the radiation energy of the target, it has the ability to work all day that the visible-light detection system cannot achieve, at the same time, infrared system is a passive detection system, does not need active detection technology such as radar, which requires large radiation power or a larger expandable antenna. It is more suitable for airborne applications, therefore, infrared imaging based on the aircraft and aerostat platform, has been an important means of monitoring the ground. However, due to detector limitations, the spatial resolution of current infrared cameras or spectrographs and the total field coverage of view are generally not satisfied the customer's requirements. This paper proposes an airborne infrared camera imaging method based on multi-planar arrays, using frame-type imaging array. In order to provide large ground coverage together with good spatial resolution, the mirror is drove to scan rapidly by the galvanometer. The scanning mirror works at staring imagery mode. During multi-planar detectors exposure and imaging, the mirror moves to the staring position. There is more than 10 % overlapping sensor foot prints between two adjacent frames, and the functions of image matching algorithms are used to ensure the seamless butting. This imaging method improves the system integration time, and effectively improves the sensitivity of infrared systems; frame-type imaging solves the serious image distortion caused by the platform attitude.

MR imaging of the toracic aorta

International Nuclear Information System (INIS)

Garbagnati, F.; Castoldi, M.C.; Bianchini, E.

1988-01-01

Various pathological conditions of the thoracic aorta were studied by MR Imaging in 31 patients: 23 were aneurysms (branching and non-branching), 2 artero-venous fistulae, 2 aortic prostheses, 2 Marfan's syndromes, 1 coronary sinus aneurysm, and 1 isthmic stenosis. MRI studies were always performed on patients who had been examined by other imaging procedures. A comparative study was carried out on the results of MRI, angiography, computerized tomography, and ultrasounds. The possibility of propedeutic protocol was explored. Our experience, in accordance with the literature on the subject, indicates MRI as the procedure of choice in the study of aneurysms of the toracic aorta. The advantages offered by MRI-the high natural contrast between circulating blood and the supporting structures, the possibility of obtaining multiplanar images as well as data on intraluminal, parietal, and extraparietal conditions-make it a highly competitive procedure if compared to either CT or angiography. While awaiting further evidence, the use of a propedeutic protocol in non-aneurysmatic diseases is still not advisable, due to insufficient patient population, and to the lack of a consistent literature on the subject

MR imaging of prostate cancer; MR-Tomographie des Prostatakarzinoms

Energy Technology Data Exchange (ETDEWEB)

Heuck, A.; Scheidler, J.; Sommer, B.; Graser, A. [Radiologisches Zentrum Muenchen-Pasing (Germany); Mueller-Lisse, U.G. [Institut fuer Klinische Radiologie, Universitaet Muenchen (Germany); Massmann, J. [Gemeinschaftspraxis Pathologie, Muenchen (Germany)

2003-06-01

Accurate diagnosis and staging of prostate cancer (PC) is developing into an important health care issue in light of the high incidence of PC and the improvements in stage-adapted therapy. The purpose of this paper is to provide an overview on the current role of MR imaging and MR spectroscopy in the diagnosis and staging of PC.Material and methods Pertinent literature was searched and evaluated to collect information on current clinical indications, study techniques, diagnostic value, and limitations of magnetic resonance imaging and spectroscopy. Major indications for MR imaging of patients with supected PC are to define tumor location before biopsy when clinical or TRUS findings are inconclusive, and to provide accurate staging of histologically proven PC to ascertain effective therapy. Current MR imaging techniques for the evaluation of PC include multiplanar high-resolution T2-weighted FSE and T1-weighted SE sequences using combined endorectal and phased-array coils. Using these techniques, the reported accuracy of MR imaging for the diagnosis of extracapsular tumor extension ranges between 82 and 88% with sensitivities between 80 and 95%, and specificities between 82 and 93%. Typical MR findings of PC in different stages of disease, as well as diagnostic problems, such as chronic prostatitis, biopsy-related hemorrhage and therapy-related changes of prostatic tissue are discussed. In addition, the current perspectives and limitations of MR spectroscopy in PC are summarized. Current MR imaging techniques provide important diagnostic information in the pretherapeutic workup of PC including a high staging accuracy, and is superior to TRUS. (orig.) [German] Der Diagnostik des Prostatakarzinoms kommt wegen seiner hohen Inzidenz und den verbesserten stadienadaptierten Therapiemoeglichkeiten eine grosse Bedeutung zu. Dabei spielen bildgebende Verfahren bei den klinisch oft unzureichend diagnostizierbaren Faellen eine wesentliche Rolle fuer die praetherapeutische

Magnetic resonance spectroscopy as an imaging method

International Nuclear Information System (INIS)

Bomsdorf, H.; Imme, M.; Jensen, D.; Kunz, D.; Menhardt, W.; Ottenberg, K.; Roeschmann, P.; Schmidt, K.H.; Tschendel, O.; Wieland, J.

1990-01-01

An experimental Magnetic Resonance (MR) system with 4 tesla flux density was set up. For that purpose a data acquisition system and RF coils for resonance frequencies up to 170 MHz were developed. Methods for image guided spectroscopy as well as spectroscopic imaging focussing on the nuclei 1 H and 13 C were developed and tested on volunteers and selected patients. The advantages of the high field strength with respect to spectroscopic studies were demonstrated. Developments of a new fast imaging technique for the acquisition of scout images as well as a method for mapping and displaying the magnetic field inhomogeneity in-vivo represent contributions to the optimisation of the experimental procedure in spectroscopic studies. Investigations on the interaction of RF radiation with the exposed tissue allowed conclusions regarding the applicability of MR methods at high field strengths. Methods for display and processing of multi-dimensional spectroscopic imaging data sets were developed and existing methods for real-time image synthesis were extended. Results achieved in the field of computer aided analysis of MR images comprised new techniques for image background detection, contour detection and automatic image interpretation as well as knowledge bases for textural representation of medical knowledge for diagnosis. (orig.) With 82 refs., 3 tabs., 75 figs [de

Recent advances in imaging technologies in implant dentistry

Directory of Open Access Journals (Sweden)

Sharad Sahai

2015-01-01

Full Text Available Dental implants have become a part of routine treatment plans in oral rehabilitation. Diagnostic imaging is critical to presurgical treatment planning and the success of implants. Various imaging modalities may aid the placing of implants in an appropriate location with relative ease and also obtain a predictable outcome. Cross-sectional imaging techniques such as computed tomography (CT and, more recently, cone beam-computed tomography (CBCT are invaluable during preoperative planning for endosseous dental implantation procedures. An understanding of geometric and software parameters, and image formatting options to maximize image display is necessary to optimize diagnostic yield while maintaining minimal patient radiation dose. Multiplanar CT or CBCT images contain far more detailed information of the maxillofacial region than do panoramic or other bidimensional (2D images and necessitate a thorough knowledge of the tridimensional (3D anatomy of the region and considerations of variability in the range of the anatomically normal. This article provides: (1 an overview of the fundamental principles of operation of maxillofacial CT and CBCT; (2 an understanding of image processing and display protocols specific to pre-implant bone assessment; (3 the basics of qualitative and quantitative bone evaluation; and (4 an introduction to image-guided implant surgery using custom or computer-generated surgical guides.

CT and MR imaging of the normal and pathologic conditions of the facial nerve

Energy Technology Data Exchange (ETDEWEB)

Jaeger, Lorenz E-mail: jaeger@ikra.med.uni-muenchen.de; Reiser, Maximilian

2001-11-01

Computed tomography (CT) and magnetic resonance imaging (MRI) are well established imaging modalities to examine the facial nerve as well as the course of the facial nerve itself. High spatial resolution is guaranteed not only in the x- and y-axis, but also in the z-axis using multislice spiral CT. With this technique, reformatted multiplanar images in oblique planes, avoiding additional examinations in the coronal plane, facilitate the delineation of the facial nerve canal. This is beneficial in patients with temporal bone trauma, malformation or osseous changes. MR has a superior soft-tissue contrast to CT that enables imaging of the facial nerve itself. Therefore the normal facial nerve as well as pathologic changes of the facial nerve is readily visualized from the brain stem to the parotid gland. This review article presents anatomy, pathology and imaging strategies in the diagnostics of the facial nerve.

Comparison of different radiographic methods for the detection of the mandibular canal

International Nuclear Information System (INIS)

Kim, Eun Kyung

2003-01-01

To compare the visibility of the mandibular canal at the different radiographic methods such as conventional panoramic radiographs, Vimplant multiplanar reformatting (MPR)-CT panoramic images, Vimplant MPR-CT paraxial images and film-based DentaScan MPR-CT images. Data of 11 mandibular dental implant patients, who had been planned treatment utilizing both panoramic and MPR-CT examination with DentaScan software (GE Medical systems, Milwaukee, USA), were used in this study. The archived axial CT data stored on CD-R discs were transferred to a personal computer with 17' LCD monitor. Paraxial and panoramic images were reconstructed using Vimplant software (CyberMed Inc., Seoul, Korea). Conventional panoramic radiographs, monitor-based Vimplant MPR-CT panoramic images, monitor-based Vimplant MPR-CT paraxial images, and film-based DentaScan MPR-CT images were evaluated for visibility of the mandibular canal at the mental foramen, 1 cm, 2 cm, and 3 cm posterior to mental foramen using the 4-point grading score. Vimplant MPR-CT panoramic, paraxial, and DentaScan MPR-CT images revealed significantly clearer images than conventional panoramic radiographs. Particularly at the region 1 cm posterior to mental foramen, conventional panoramic radiographs showed a markedly lower percentage of 'excellent' mandibular canal images than images produced by other modalities. Vimplant MPR-CT and DentaScan MPR-CT images did not show significant difference in visibility of the mandibular canal. The study results shoe that Vimplant and DentaScan MPR-CT imaging systems offer significantly better images of the mandibular canal than conventional panoramic radiograph.

Survey: interpolation methods for whole slide image processing.

Science.gov (United States)

Roszkowiak, L; Korzynska, A; Zak, J; Pijanowska, D; Swiderska-Chadaj, Z; Markiewicz, T

2017-02-01

Evaluating whole slide images of histological and cytological samples is used in pathology for diagnostics, grading and prognosis . It is often necessary to rescale whole slide images of a very large size. Image resizing is one of the most common applications of interpolation. We collect the advantages and drawbacks of nine interpolation methods, and as a result of our analysis, we try to select one interpolation method as the preferred solution. To compare the performance of interpolation methods, test images were scaled and then rescaled to the original size using the same algorithm. The modified image was compared to the original image in various aspects. The time needed for calculations and results of quantification performance on modified images were also compared. For evaluation purposes, we used four general test images and 12 specialized biological immunohistochemically stained tissue sample images. The purpose of this survey is to determine which method of interpolation is the best to resize whole slide images, so they can be further processed using quantification methods. As a result, the interpolation method has to be selected depending on the task involving whole slide images. © 2016 The Authors Journal of Microscopy © 2016 Royal Microscopical Society.

MR imaging evaluation of congenital spine anomalies

International Nuclear Information System (INIS)

Bury, E.A.; Zimmerman, R.A.; Grossman, R.I.; Goldberg, H.I.; Bilaniuk, L.T.; Hackney, D.B.

1987-01-01

Over a 2-year period, 135 patients between the ages of 1 week and 18 years were examined with MR imaging for possible congenital anomalies of the spine and spinal cord. Tethered cords with various other associated pathologies such as lipomas and myelomeningoceles were found in 36 patients. The remaining abnormal examinations consisted of syrinxes, Chiari malformations, diastematomyelia, and conus masses. In 55 patients the studies were interpreted as normal. Of these, three were subsequently shown by surgery of myelography to be abnormal. The first had a thickened filum with a small epidermoid, the second a thickened filum, and the third, with only sagittal images, a diastematomyelia. Children presenting with symptoms highly suspicious for congenital abnormalities but with a normal MR study in multiple planes may still require further evaluation with myelography. Multiplanar MR examination in most instances will be a sufficient evaluation for congenital anomalies

Method of assessing heterogeneity in images

Science.gov (United States)

Jacob, Richard E.; Carson, James P.

2016-08-23

A method of assessing heterogeneity in images is disclosed. 3D images of an object are acquired. The acquired images may be filtered and masked. Iterative decomposition is performed on the masked images to obtain image subdivisions that are relatively homogeneous. Comparative analysis, such as variogram analysis or correlogram analysis, is performed of the decomposed images to determine spatial relationships between regions of the images that are relatively homogeneous.

A Study on the Improvement of Digital Periapical Images using Image Interpolation Methods

International Nuclear Information System (INIS)

Song, Nam Kyu; Koh, Kwang Joon

1998-01-01

Image resampling is of particular interest in digital radiology. When resampling an image to a new set of coordinate, there appears blocking artifacts and image changes. To enhance image quality, interpolation algorithms have been used. Resampling is used to increase the number of points in an image to improve its appearance for display. The process of interpolation is fitting a continuous function to the discrete points in the digital image. The purpose of this study was to determine the effects of the seven interpolation functions when image resampling in digital periapical images. The images were obtained by Digora, CDR and scanning of Ektaspeed plus periapical radiograms on the dry skull and human subject. The subjects were exposed to intraoral X-ray machine at 60 kVp and 70 kVp with exposure time varying between 0.01 and 0.50 second. To determine which interpolation method would provide the better image, seven functions were compared ; (1) nearest neighbor (2) linear (3) non-linear (4) facet model (5) cubic convolution (6) cubic spline (7) gray segment expansion. And resampled images were compared in terms of SNR (Signal to Noise Ratio) and MTF (Modulation Transfer Function) coefficient value. The obtained results were as follows ; 1. The highest SNR value (75.96 dB) was obtained with cubic convolution method and the lowest SNR value (72.44 dB) was obtained with facet model method among seven interpolation methods. 2. There were significant differences of SNR values among CDR, Digora and film scan (P 0.05). 4. There were significant differences of MTF coefficient values between linear interpolation method and the other six interpolation methods (P<0.05). 5. The speed of computation time was the fastest with nearest neighbor method and the slowest with non-linear method. 6. The better image was obtained with cubic convolution, cubic spline and gray segment method in ROC analysis. 7. The better sharpness of edge was obtained with gray segment expansion method

Magnetic resonance imaging of elephantiasis neuromatosa

Energy Technology Data Exchange (ETDEWEB)

Stevens, K.J.; Sully, L.; Preston, B.J. [Department of Radiology, University Hospital, Queen`s Medical Centre, Nottingham (United Kingdom); Ludman, C.N. [Department of Radiology, University Hospital, Queen`s Medical Centre, Nottingham (United Kingdom)]|[Division of Academic Radiology, University Hospital, Queen`s Medical Centre, Nottingham (United Kingdom)

1998-12-01

We present the case of a 43-year-old man with neurofibromatosis type 1 who developed elephantiasis neuromatosa of his left leg. The gross limb enlargement was extremely disfiguring, and resulted in such severe disability that he was only able to walk a very short distance using crutches. Previous debulking procedures had resulted in massive blood loss, and prior to attempting further surgical intervention MRI studies were requested. Taking advantage of the excellent tissue characterisation and multiplanar imaging capabilities of MRI, we were able to assess the extent of soft tissue and osseous involvement. The use of recently developed MR angiographic sequences enabled us to non-invasively provide detailed images to assess the relationship of the lesions to the major vessels, as well as the vascular supply and angiographic features of the lesions themselves. This article describes our MRI-based findings, which precluded debulking surgery in this unusual manifestation of neurofibromatosis. (orig.) With 6 figs., 23 refs.

Magnetic resonance imaging of elephantiasis neuromatosa

International Nuclear Information System (INIS)

Stevens, K.J.; Sully, L.; Preston, B.J.; Ludman, C.N.

1998-01-01

We present the case of a 43-year-old man with neurofibromatosis type 1 who developed elephantiasis neuromatosa of his left leg. The gross limb enlargement was extremely disfiguring, and resulted in such severe disability that he was only able to walk a very short distance using crutches. Previous debulking procedures had resulted in massive blood loss, and prior to attempting further surgical intervention MRI studies were requested. Taking advantage of the excellent tissue characterisation and multiplanar imaging capabilities of MRI, we were able to assess the extent of soft tissue and osseous involvement. The use of recently developed MR angiographic sequences enabled us to non-invasively provide detailed images to assess the relationship of the lesions to the major vessels, as well as the vascular supply and angiographic features of the lesions themselves. This article describes our MRI-based findings, which precluded debulking surgery in this unusual manifestation of neurofibromatosis. (orig.)

Digital image envelope: method and evaluation

Science.gov (United States)

Huang, H. K.; Cao, Fei; Zhou, Michael Z.; Mogel, Greg T.; Liu, Brent J.; Zhou, Xiaoqiang

2003-05-01

Health data security, characterized in terms of data privacy, authenticity, and integrity, is a vital issue when digital images and other patient information are transmitted through public networks in telehealth applications such as teleradiology. Mandates for ensuring health data security have been extensively discussed (for example The Health Insurance Portability and Accountability Act, HIPAA) and health informatics guidelines (such as the DICOM standard) are beginning to focus on issues of data continue to be published by organizing bodies in healthcare; however, there has not been a systematic method developed to ensure data security in medical imaging Because data privacy and authenticity are often managed primarily with firewall and password protection, we have focused our research and development on data integrity. We have developed a systematic method of ensuring medical image data integrity across public networks using the concept of the digital envelope. When a medical image is generated regardless of the modality, three processes are performed: the image signature is obtained, the DICOM image header is encrypted, and a digital envelope is formed by combining the signature and the encrypted header. The envelope is encrypted and embedded in the original image. This assures the security of both the image and the patient ID. The embedded image is encrypted again and transmitted across the network. The reverse process is performed at the receiving site. The result is two digital signatures, one from the original image before transmission, and second from the image after transmission. If the signatures are identical, there has been no alteration of the image. This paper concentrates in the method and evaluation of the digital image envelope.

Comparative analysis of different methods for image enhancement

Institute of Scientific and Technical Information of China (English)

吴笑峰; 胡仕刚; 赵瑾; 李志明; 李劲; 唐志军; 席在芳

2014-01-01

Image enhancement technology plays a very important role to improve image quality in image processing. By enhancing some information and restraining other information selectively, it can improve image visual effect. The objective of this work is to implement the image enhancement to gray scale images using different techniques. After the fundamental methods of image enhancement processing are demonstrated, image enhancement algorithms based on space and frequency domains are systematically investigated and compared. The advantage and defect of the above-mentioned algorithms are analyzed. The algorithms of wavelet based image enhancement are also deduced and generalized. Wavelet transform modulus maxima (WTMM) is a method for detecting the fractal dimension of a signal, it is well used for image enhancement. The image techniques are compared by using the mean (μ), standard deviation (s), mean square error (MSE) and PSNR (peak signal to noise ratio). A group of experimental results demonstrate that the image enhancement algorithm based on wavelet transform is effective for image de-noising and enhancement. Wavelet transform modulus maxima method is one of the best methods for image enhancement.

Magnetic resonance imaging of the abdomen and pelvis

International Nuclear Information System (INIS)

Anon.

1989-01-01

Magnetic resonance imaging (MRI) of the abdomen presents greater inherent difficulties than other anatomic regions. However, new techniques now allow imaging comparable in quality to computed tomography (CT). Magnetic resonance imaging offers the advantages of greater tissue contrast, multiplanar imaging, and lack of ionizing radiation or risk of toxic reactions from iodinated contrast media. Its use remains limited by high cost, limited availability, lack of a bowel contrast agent, and long imaging time, which some patients cannot tolerate. In many areas of abdominal imaging, MRI is now comparable to CT, but because of the greater availability and lesser cost, CT remains the procedure of choice. Magnetic resonance imaging is more accurate for staging neoplasms of the liver, adrenal glands, kidneys, bladder, prostate, uterus, and cervix and may aid in diagnosis of hepatic, adrenal, and uterine masses. In selected patients, especially those in whom CT is inconclusive or those who cannot tolerate iodinated contrast material, MRI can provide valuable information. Development of faster scanning techniques and MRI contrast agents and wider availability will probably increase the usefulness of abdominal MRI. At this time, MRI complements other abdominal imaging procedures. In a small number of patients, however, it can provide unique information in a virtually risk-free manner

Computational methods for molecular imaging

CERN Document Server

Shi, Kuangyu; Li, Shuo

2015-01-01

This volume contains original submissions on the development and application of molecular imaging computing. The editors invited authors to submit high-quality contributions on a wide range of topics including, but not limited to: • Image Synthesis & Reconstruction of Emission Tomography (PET, SPECT) and other Molecular Imaging Modalities • Molecular Imaging Enhancement • Data Analysis of Clinical & Pre-clinical Molecular Imaging • Multi-Modal Image Processing (PET/CT, PET/MR, SPECT/CT, etc.) • Machine Learning and Data Mining in Molecular Imaging. Molecular imaging is an evolving clinical and research discipline enabling the visualization, characterization and quantification of biological processes taking place at the cellular and subcellular levels within intact living subjects. Computational methods play an important role in the development of molecular imaging, from image synthesis to data analysis and from clinical diagnosis to therapy individualization. This work will bring readers fro...

Eleven fetal echocardiographic planes using 4-dimensional ultrasound with spatio-temporal image correlation (STIC): a logical approach to fetal heart volume analysis.

Science.gov (United States)

Jantarasaengaram, Surasak; Vairojanavong, Kittipong

2010-09-15

Theoretically, a cross-sectional image of any cardiac planes can be obtained from a STIC fetal heart volume dataset. We described a method to display 11 fetal echocardiographic planes from STIC volumes. Fetal heart volume datasets were acquired by transverse acquisition from 200 normal fetuses at 15 to 40 weeks of gestation. Analysis of the volume datasets using the described technique to display 11 echocardiographic planes in the multiplanar display mode were performed offline. Volume datasets from 18 fetuses were excluded due to poor image resolution. The mean visualization rates for all echocardiographic planes at 15-17, 18-22, 23-27, 28-32 and 33-40 weeks of gestation fetuses were 85.6% (range 45.2-96.8%, N = 31), 92.9% (range 64.0-100%, N = 64), 93.4% (range 51.4-100%, N = 37), 88.7%(range 54.5-100%, N = 33) and 81.8% (range 23.5-100%, N = 17) respectively. Overall, the applied technique can favorably display the pertinent echocardiographic planes. Description of the presented method provides a logical approach to explore the fetal heart volumes.

Ring artifact correction for high-resolution micro CT

International Nuclear Information System (INIS)

Kyriakou, Yiannis; Prell, Daniel; Kalender, Willi A

2009-01-01

In high-resolution micro CT using flat detectors (FD), imperfect or defect detector elements may cause concentric-ring artifacts due to their continuous over- or underestimation of attenuation values, which often disturb image quality. We here present a dedicated image-based ring artifact correction method for high-resolution micro CT, based on median filtering of the reconstructed image and working on a transformed version of the reconstructed images in polar coordinates. This post-processing method reduced ring artifacts in the reconstructed images and improved image quality for phantom and in in vivo scans. Noise and artifacts were reduced both in transversal and in multi-planar reformations along the longitudinal axis. (note)

Curved planar reconstruction of MR images in focal cortical dysplasia of the brain

International Nuclear Information System (INIS)

Chung, Gyung Ho; Lee, Sang Yong; Kim, Chong So; Kim, Young Kon; Lee, Young Hwan; Jeong, Su Hyun

2002-01-01

To describe curved planar reconstruction imaging (CPR) and determine its usefulness in the evaluation of focal cortical dysplasia of the brain. In 17 cases of focal cortical dysplasia (cortical dysplasia (n=9), schizencephaly (n=5), and heterotopia (n=3), CPR images were created using a multiplanar reconstruction program and imaging data obtained during T1 magnetization prepared rapid acquisition gradient-echo MR imaging. We assessed the precise configuration of abnormalities and their relation to adjacent gyri and sulci. CPRI showed the brain cortex as a 2D panoramic image, demonstrating the precise configurations and locations of dysplasia-associated abnormalities and their relation to adjacent gyri and sulci, and the precise shape of the gray-white matter interface. CPRI can provide important radiological information about the extension and configuration of focal cortical dysplasia, and its relation to neighboring cortical structures. We believe that CPRI should form an essential part of the routine investigation os suspected cases of focal cortical dysplasia

Interventional magnetic resonance imaging - non-invasive imaging for interventions; Interventionelle Magnetresonanztomographie - nichtinvasive Bildgebung fuer Interventionen

Energy Technology Data Exchange (ETDEWEB)

Buecker, A.; Adam, G.; Neuerburg, J.M.; Glowinski, A.; Tacke, J.; Guenther, R.W. [Technische Hochschule Aachen (Germany). Medizinische Fakultaet

2000-02-01

As a prerequisite for MR-guidance of interventional procedures, instruments have to be well depicted in the MR image without obscuring or distorting the underlying anatomy. For non-vascular interventions the imaging speed has to be in the range of seconds while control of vascular interventions requires real time imaging speed. The imaging contrast has to be maintained as well as a high spatial resolution. Furthermore, sufficient patient access has to be provided by the MR scanner. Neither an ideal magnet nor the optimal single sequence are available to fulfill the above-mentioned criteria. The type of sequence - gradient echo versus spin echo - together with changing of the echo time and phase encording direction will ensure an appropriate size of the artifact and thereby of the appearance of the instrument in the MR image. The feasibility of non-vascular MR-guided interventions has been proved at field strengths ranging from 0.064 T to 1.5 T. Bone biopsies, soft tissue biopsies, drainages, and control of interstitial thermo- and cryotherapy have been reported. For vascular interventions, different real time MR strategies are currently under investigation. The development of dedicated catheters and guide wires has enabled MR-guided dilatations, stenting, placement of vena cava filters, and TIPS procedures. Considering the fast progress being made in this field, there can be no question that interventional MRI will become a well-accepted clinical tool offering potential advantages such as excellent soft tissue contrast, multiplanar imaging, flow measurements, high resolution imaging of vessel walls, and lack of ionizing radiation. (orig.) [German] Zur Durchfuehrung MR-gesteuerter Interventionen muessen interventionelle Instrumente gut sichtbar, aber ohne stoerende Artefakte darstellbar sein. Die Geschwindigkeit der Bilderstellung sollte fuer nichtvaskulaere Interventionen im Sekundenbereich liegen und fuer vaskulaere Interventionen Echtzeitbildgebung liefern. Weder

A proposal of a three-dimensional CT measurement method of maxillofacial structure

International Nuclear Information System (INIS)

Tanaka, Ray; Hayashi, Takafumi

2007-01-01

Three-dimensional CT measurement is put in practice in order to grasp the pathological condition on diseases such as the temporomandibular joint disorder, maxillofacial anomaly, jaw deformity, or fracture which cause the morphologic changes of the maxillofacial bones. On the 3D measurement, the unique system that is obtained by volume rendering 3D images with a simultaneous reference of axial images combined with coronal and sagittal multi-planar reconstruction (MPR) images (we call this MPR referential method), is employed in order to define the measurement points. Our purpose in this report is to indicate the usefulness of this unique method by comparing with the common way to define the measurement points on only 3D reconstruction images without consulting of MPR images. Clinical CT data obtained from a male patient with skeletal malocclusion was used. Contiguous axial images were reconstructed at 4 times magnification, with a reconstruction interval of 0.5 mm, focused on the temporomandibular joint region in his left side. After these images were converted to Digital Imaging and Communications in Medicine (DICOM) format and sent to personal computer (PC), 3D reconstruction image was created using free 3D DICOM medical image viewer. The coordinates of 3 measurement points (the lateral and medial pole of the mandibular condyle, and the left foramen ovale) were defined with MPR images (MPR coordinates) as reference coordinates, and then the coordinates that were defined on only 3D reconstruction image without consulting to MPR images (3D coordinates) were compared to those of MPR coordinates. Three examiners were engaged independently 10 times for every measurement point. In our result, there was no correspondence between 3D coordinates and MPR coordinates, and contribution of 3D coordinates showed a variety in every measurement point and in every observer. We deemed that ''MPR referential method'' is useful to assess the location of the target point of anatomical

Dynamic PET Image reconstruction for parametric imaging using the HYPR kernel method

Science.gov (United States)

Spencer, Benjamin; Qi, Jinyi; Badawi, Ramsey D.; Wang, Guobao

2017-03-01

Dynamic PET image reconstruction is a challenging problem because of the ill-conditioned nature of PET and the lowcounting statistics resulted from short time-frames in dynamic imaging. The kernel method for image reconstruction has been developed to improve image reconstruction of low-count PET data by incorporating prior information derived from high-count composite data. In contrast to most of the existing regularization-based methods, the kernel method embeds image prior information in the forward projection model and does not require an explicit regularization term in the reconstruction formula. Inspired by the existing highly constrained back-projection (HYPR) algorithm for dynamic PET image denoising, we propose in this work a new type of kernel that is simpler to implement and further improves the kernel-based dynamic PET image reconstruction. Our evaluation study using a physical phantom scan with synthetic FDG tracer kinetics has demonstrated that the new HYPR kernel-based reconstruction can achieve a better region-of-interest (ROI) bias versus standard deviation trade-off for dynamic PET parametric imaging than the post-reconstruction HYPR denoising method and the previously used nonlocal-means kernel.

Apparatus and method X-ray image processing

International Nuclear Information System (INIS)

1984-01-01

The invention relates to a method for X-ray image processing. The radiation passed through the object is transformed into an electric image signal from which the logarithmic value is determined and displayed by a display device. Its main objective is to provide a method and apparatus that renders X-ray images or X-ray subtraction images with strong reduction of stray radiation. (Auth.)

Magnetic resonance imaging in gynecology and obstetrics - possibilities and limits of the method; Diagnostyka rezonansu magnetycznego w ginekologii i poloznictwie - mozliwosci i ograniczenia metody

Energy Technology Data Exchange (ETDEWEB)

Tyminska, B.; Jakubowski, W. [Zaklad Diagnostyki Obrazowej, 2. Wydzial Lekarski, Akademia Medyczna, Warsaw (Poland)

1994-12-31

MRI of female pelvis gains clinical acceptance. Use of contrast media and dynamic examinations enables exact staging of uteric cancer. MRI- multiplanar and noninvasive, with excellent contrast and spatial resolution has raising popularity in gynecology and obstetrician diagnosis. (author) 14 refs, 4 figs, 2 tabs

On an image reconstruction method for ECT

Science.gov (United States)

Sasamoto, Akira; Suzuki, Takayuki; Nishimura, Yoshihiro

2007-04-01

An image by Eddy Current Testing(ECT) is a blurred image to original flaw shape. In order to reconstruct fine flaw image, a new image reconstruction method has been proposed. This method is based on an assumption that a very simple relationship between measured data and source were described by a convolution of response function and flaw shape. This assumption leads to a simple inverse analysis method with deconvolution.In this method, Point Spread Function (PSF) and Line Spread Function(LSF) play a key role in deconvolution processing. This study proposes a simple data processing to determine PSF and LSF from ECT data of machined hole and line flaw. In order to verify its validity, ECT data for SUS316 plate(200x200x10mm) with artificial machined hole and notch flaw had been acquired by differential coil type sensors(produced by ZETEC Inc). Those data were analyzed by the proposed method. The proposed method restored sharp discrete multiple hole image from interfered data by multiple holes. Also the estimated width of line flaw has been much improved compared with original experimental data. Although proposed inverse analysis strategy is simple and easy to implement, its validity to holes and line flaw have been shown by many results that much finer image than original image have been reconstructed.

Evaluation of the resolving power of different angles in MPR images of 16DAS-MDCT

International Nuclear Information System (INIS)

Kimura, Mikio; Usui, Junshi; Nozawa, Takeo

2007-01-01

In this study, we evaluated the resolving power of three-dimensional (3D) multiplanar reformation (MPR) images with various angles by using 16 data acquisition system multi detector row computed tomography (16DAS-MDCT). We reconstructed the MPR images using data with a 0.75 mm slice thickness of the axial image in this examination. To evaluate resolving power, we used an original new phantom (RC phantom) that can be positioned at any slice angle in MPR images. We measured the modulation transfer function (MTF) by using the methods of measuring pre-sampling MTF, and used Fourier transform of image data of the square wave chart. The scan condition and image reconstruction condition that were adopted in this study correspond to the condition that we use for three-dimensional computed tomographic angiography(3D-CTA) examination of the head in our hospital. The MTF of MPR images showed minimum values at slice angles in parallel with the axial slice, and showed maximum values at the sagittal slice and coronal slice angles that are parallel to the Z-axis. With an oblique MPR image, MTF did not change with angle changes in the oblique sagittal slice plane, but in the oblique coronal slice plane, MTF increased as the tilt angle increased from the axial plane to the Z plane. As a result, we could evaluate the resolving power of a head 3D image by measuring the MTF of the axial image and sagittal image or the coronal image. (author)

[Evaluation of the resolving power of different angles in MPR images of 16DAS-MDCT].

Science.gov (United States)

Kimura, Mikio; Usui, Junshi; Nozawa, Takeo

2007-03-20

In this study, we evaluated the resolving power of three-dimensional (3D) multiplanar reformation (MPR) images with various angles by using 16 data acquisition system multi detector row computed tomography (16DAS-MDCT) . We reconstructed the MPR images using data with a 0.75 mm slice thickness of the axial image in this examination. To evaluate resolving power, we used an original new phantom (RC phantom) that can be positioned at any slice angle in MPR images. We measured the modulation transfer function (MTF) by using the methods of measuring pre-sampling MTF, and used Fourier transform of image data of the square wave chart. The scan condition and image reconstruction condition that were adopted in this study correspond to the condition that we use for three-dimensional computed tomographic angiography (3D-CTA) examination of the head in our hospital. The MTF of MPR images showed minimum values at slice angles in parallel with the axial slice, and showed maximum values at the sagittal slice and coronal slice angles that are parallel to the Z-axis. With an oblique MPR image, MTF did not change with angle changes in the oblique sagittal slice plane, but in the oblique coronal slice plane, MTF increased as the tilt angle increased from the axial plane to the Z plane. As a result, we could evaluate the resolving power of a head 3D image by measuring the MTF of the axial image and sagittal image or the coronal image.

A NEW IMAGE REGISTRATION METHOD FOR GREY IMAGES

Institute of Scientific and Technical Information of China (English)

Nie Xuan; Zhao Rongchun; Jiang Zetao

2004-01-01

The proposed algorithm relies on a group of new formulas for calculating tangent slope so as to address angle feature of edge curves of image. It can utilize tangent angle features to estimate automatically and fully the rotation parameters of geometric transform and enable rough matching of images with huge rotation difference. After angle compensation, it can search for matching point sets by correlation criterion, then calculate parameters of affine transform, enable higher-precision emendation of rotation and transferring. Finally, it fulfills precise matching for images with relax-tense iteration method. Compared with the registration approach based on wavelet direction-angle features, the matching algorithm with tangent feature of image edge is more robust and realizes precise registration of various images. Furthermore, it is also helpful in graphics matching.

Enhancing the (MSLDIP) image steganographic method (ESLDIP method)

Science.gov (United States)

Seddik Saad, Al-hussien

2011-10-01

Message transmissions over the Internet still have data security problem. Therefore, secure and secret communication methods are needed for transmitting messages over the Internet. Cryptography scrambles the message so that it cannot be understood. However, it makes the message suspicious enough to attract eavesdropper's attention. Steganography hides the secret message within other innocuous-looking cover files (i.e. images, music and video files) so that it cannot be observed [1].The term steganography originates from the Greek root words "steganos'' and "graphein'' which literally mean "covered writing''. It is defined as the science that involves communicating secret data in an appropriate multimedia carrier, e.g., image, audio text and video files [3].Steganographic techniques allow one party to communicate information to another without a third party even knowing that the communication is occurring. The ways to deliver these "secret messages" vary greatly [3].Our proposed method called Enhanced SLDIP (ESLDIP). In which the maximmum hiding capacity (MHC) of proposed ESLDIP method is higher than the previously proposed MSLDIP methods and the PSNR of the ESLDIP method is higher than the MSLDIP PSNR values', which means that the image quality of the ESLDIP method will be better than MSLDIP method and the maximmum hiding capacity (MHC) also improved. The rest of this paper is organized as follows. In section 2, steganography has been discussed; lingo, carriers and types. In section 3, related works are introduced. In section 4, the proposed method will be discussed in details. In section 5, the simulation results are given and Section 6 concludes the paper.

Numerical methods for image registration

CERN Document Server

Modersitzki, Jan

2003-01-01

Based on the author's lecture notes and research, this well-illustrated and comprehensive text is one of the first to provide an introduction to image registration with particular emphasis on numerical methods in medical imaging. Ideal for researchers in industry and academia, it is also a suitable study guide for graduate mathematicians, computer scientists, engineers, medical physicists, and radiologists.Image registration is utilised whenever information obtained from different viewpoints needs to be combined or compared and unwanted distortion needs to be eliminated. For example, CCTV imag

Image restoration and processing methods

International Nuclear Information System (INIS)

Daniell, G.J.

1984-01-01

This review will stress the importance of using image restoration techniques that deal with incomplete, inconsistent, and noisy data and do not introduce spurious features into the processed image. No single image is equally suitable for both the resolution of detail and the accurate measurement of intensities. A good general purpose technique is the maximum entropy method and the basis and use of this will be explained. (orig.)

MR imaging of congenital heart diseases in adolescents and adults

International Nuclear Information System (INIS)

Choe, Yeon Hyeon; Kang, I Seok; Park, Seung Woo; Lee, Heung Jae

2001-01-01

Echocardiography and catheterization angiography suffer certain limitations in the evaluation of congenital heart diseases in adults, though these are overcome by MRI, in which a wide field-of view, unlimited multiplanar imaging capability and three-dimensional contrast-enhanced MR angiography techniques are used. In adults, recently introduced fast imaging techniques provide cardiac MR images of sufficient quality and with less artifacts. Ventricular volume, ejection fraction, and vascular flow measurements, including pressure gradients and pulmonary-to-systemic flow ratio, can be calculated or obtained using fast cine MRI, phase-contrast MR flow-velocity mapping, and semiautomatic analysis software. MRI is superior to echocardiography in diagnosing partial anomalous pulmonary venous connection, unroofed coronary sinus, anomalies of the pulmonary arteries, aorta and systemic veins, complex heart diseases, and postsurgical sequelae. Biventricular function is reliably evaluated with cine MRI after repair of tetralogy of Fallot, and Senning's and Mustard's operations. MRI has an important and growing role in the morphologic and functional assessment of congenital heart diseases in adolescents and adults

Comparison of the image quality between volumetric and conventional high-resolution CT with 64-slice row CT

International Nuclear Information System (INIS)

Gao Yanli; Zhang Lei; Zhao Xia; Ma Min; Zhai Renyou

2008-01-01

Objective: To compare the image quality between volumetric high-resolution CT (VHRCT) and conventional high-resolution CT (CHRCT), and investigate the feasibility of VHRCT. Methods: Catphan 412 phantom was scanned with protocols of CHRCT and VHRCT on a set of GE Lightspeed VCT. The spatial-resolution (LP/cm), noise (standard deviation in an ROI) and radiation close (CTDI) were recorded for each CT scan. Difference of noise between CHRCT and VHRCT were evaluated by paired t test. In clinical study, 32 patients were scanned with VHRCT and CHRCT protocols. The image quality of CHRCT and VHRCT was rated and compared. The quality difference between CHRCT and VHRCT was assessed by Wilcoxon paired signed rank sum test. Results: In phantom study, the in-plane spatial-resolution of both VHRCT and CHRCT was 11 LP/cm for axial images and 12 LP/cm for coronal reformatted images. The noise of VHRCT and CHRCT was (69.18±2.77)HU and (54.62±2.12) HU respectively (t=-15.929, P 0.05). The quality assessment scores of VHRCT coronal reformatted images and CHRCT coronal reformatted images were 3.05 and 1.88 respectively with significant difference (Z= -5.088, P<0.01). Conclusion: The image quality of VHRCT cross-sectional image is similar to that of CHRCT. Multiplanar images with high resolution of VHRCT are recommended. The radiation dose of VHRCT remains to be optimized. (authors)

Prognostic aspects of imaging method development

International Nuclear Information System (INIS)

Steinhart, L.

1987-01-01

A survey is presented of X-ray diagnostic methods and techniques and possibilities of their further development. Promising methods include direct imaging using digital radiography. In connection with computer technology these methods achieve higher resolution. The storage of obtained images in the computer memory will allow automated processing and evaluation and the use of expert systems. Development is expected to take place especially in computerized tomography using magnetic resonance, and positron computed tomography and other non-radioactive diagnostic methods. (J.B.). 5 figs., 1 tab., 1 ref

Double-compression method for biomedical images

Science.gov (United States)

Antonenko, Yevhenii A.; Mustetsov, Timofey N.; Hamdi, Rami R.; Małecka-Massalska, Teresa; Orshubekov, Nurbek; DzierŻak, RóŻa; Uvaysova, Svetlana

2017-08-01

This paper describes a double compression method (DCM) of biomedical images. A comparison of image compression factors in size JPEG, PNG and developed DCM was carried out. The main purpose of the DCM - compression of medical images while maintaining the key points that carry diagnostic information. To estimate the minimum compression factor an analysis of the coding of random noise image is presented.

Distributed MIMO-ISAR Sub-image Fusion Method

Directory of Open Access Journals (Sweden)

Gu Wenkun

2017-02-01

Full Text Available The fast fluctuation associated with maneuvering a target’s radar cross-section often affects the imaging performance stability of traditional monostatic Inverse Synthetic Aperture Radar (ISAR. To address this problem, in this study, we propose an imaging method based on the fusion of sub-images of frequencydiversity-distributed multiple Input-Multiple Output-Inverse Synthetic Aperture Radar (MIMO-ISAR. First, we establish the analytic expression of a two-dimensional ISAR sub-image acquired by different channels of distributed MIMO-ISAR. Then, we derive the distance and azimuth distortion factors of the image acquired by the different channels. By compensating for the distortion of the ISAR image, we ultimately realize distributed MIMO-ISAR fusion imaging. Simulations verify the validity of this imaging method using distributed MIMO-ISAR.

MR imaging of abscess by use of lipid-coated iron oxide particles

International Nuclear Information System (INIS)

Chan, T.W.; Eley, C.G.S.; Kressel, H.Y.

1990-01-01

The authors of this paper investigate the potential application of lipid-coated iron oxide particles as an MR contrast agent for imaging inflammatory process by using a rat subcutaneous abscess model induced by turpentine. Ten male Sprague-Dawley rats received subcutaneous injections of 0.1 mL of turpentine in the flank. At 24-36 hours later, the rats developed a subcutaneous abscess of 1-1.8 cm. An intravenous injection of lipid-coated iron oxide particles, Ferrosome (Vestar) at doses of 25, 40, 100, 200 μg/kg was administered. The animals were imaged at 12-24 hours later on a 1.5-T magnet using a 3-inch (7.62-cm) surface coil. Two animals were also imaged 5 days later. T1-weighted, T2-weighted, and multiplanar gradient-recalled (MPGR) sequences were obtained. The abscess was then excised and examined with routine H-E and iron staining

Endometrial cancer: magnetic resonance imaging.

Science.gov (United States)

Manfredi, R; Gui, B; Maresca, G; Fanfani, F; Bonomo, L

2005-01-01

Carcinoma of the endometrium is the most common invasive gynecologic malignancy of the female genital tract. Clinically, patients with endometrial carcinoma present with abnormal uterine bleeding. The role of magnetic resonance imaging (MRI) in endometrial carcinoma is disease staging and treatment planning. MRI has been shown to be the most valuable imaging mod-ality in this task, compared with endovaginal ultrasound and computed tomography, because of its intrinsic contrast resolution and multiplanar capability. MRI protocol includes axial T1-weighted images; axial, sagittal, and coronal T2-weighted images; and dynamic gadolinium-enhanced T1-weighted imaging. MR examination is usually performed in the supine position with a phased array multicoil using a four-coil configuration. Endometrial carcinoma is isointense with the normal endometrium and myometrium on noncontrast T1-weighted images and has a variable appearance on T2-weighted images demonstrating heterogeneous signal intensity. The appearance of noninvasive endometrial carcinoma on MRI is characterized by a normal or thickened endometrium, with an intact junctional zone and a sharp tumor-myometrium interface. Invasive endometrial carcinoma is characterized disruption or irregularity of the junctional zone by intermediate signal intensity mass on T2-weighted images. Invasion of the cervical stroma is diagnosed when the low signal intensity cervical stroma is disrupted by the higher signal intensity endometrial carcinoma. MRI in endometrial carcinoma performs better than other imaging modalities in disease staging and treatment planning. Further, the accuracy and the cost of MRI are equivalent to those of surgical staging.

[3D FSPGR (fast spoiled gradient echo) magnetic resonance imaging in the diagnosis of focal cortical dysplasia in children].

Science.gov (United States)

Alikhanov, A A; Sinitsyn, V E; Perepelova, E M; Mukhin, K Iu; Demushkina, A A; Omarova, M O; Piliia, S V

2001-01-01

Small dysplastic lesions of the cerebral cortex are often missed by conventional MRI methods. The identification of subtle structural abnormalities by traditional multiplanar rectilinear slices is often limited by the complex convolutional pattern of the brain. We used a method of FSPGR (fast spoiled gradient-echo) of three-dimensional MRI data that improves the anatomical display of the sulcal structure of the hemispheric convexities. It also reduces the asymmetric sampling of gray-white matter that may lead to false-positive results. We present 5 from 12 patients with dysplastic cortical lesions in whom conventional two-dimensional and three-dimensional MRI with multiplanar reformatting was initially considered normal. Subsequent studies using 3D FSPGR identified various types of focal cortical dysplasia in all. These results indicate that an increase in the detection of subtle focal dysplastic lesions may be accomplished when one improves the anatomical display of the brain sulcal structure by performing 3D FSPGR.

Separation method of heavy-ion particle image from gamma-ray mixed images using an imaging plate

CERN Document Server

Yamadera, A; Ohuchi, H; Nakamura, T; Fukumura, A

1999-01-01

We have developed a separation method of alpha-ray and gamma-ray images using the imaging plate (IP). The IP from which the first image was read out by an image reader was annealed at 50 deg. C for 2 h in a drying oven and the second image was read out by the image reader. It was found out that an annealing ratio, k, which is defined as a ratio of the photo-stimulated luminescence (PSL) density at the first measurement to that at the second measurement, was different for alpha rays and gamma rays. By subtracting the second image multiplied by a factor of k from the first image, the alpha-ray image was separated from the alpha and gamma-ray mixed images. This method was applied to identify the images of helium, carbon and neon particles of high energies using the heavy-ion medical accelerator, HIMAC. (author)

Wavelet imaging cleaning method for atmospheric Cherenkov telescopes

Science.gov (United States)

Lessard, R. W.; Cayón, L.; Sembroski, G. H.; Gaidos, J. A.

2002-07-01

We present a new method of image cleaning for imaging atmospheric Cherenkov telescopes. The method is based on the utilization of wavelets to identify noise pixels in images of gamma-ray and hadronic induced air showers. This method selects more signal pixels with Cherenkov photons than traditional image processing techniques. In addition, the method is equally efficient at rejecting pixels with noise alone. The inclusion of more signal pixels in an image of an air shower allows for a more accurate reconstruction, especially at lower gamma-ray energies that produce low levels of light. We present the results of Monte Carlo simulations of gamma-ray and hadronic air showers which show improved angular resolution using this cleaning procedure. Data from the Whipple Observatory's 10-m telescope are utilized to show the efficacy of the method for extracting a gamma-ray signal from the background of hadronic generated images.

Advanced large airway CT imaging in children: evolution from axial to 4-D assessment

International Nuclear Information System (INIS)

Lee, Edward Y.; Zucker, Evan J.; Restrepo, Ricardo; Daltro, Pedro; Boiselle, Phillip M.

2013-01-01

Continuing advances in multidetector computed tomography (MDCT) technology are revolutionizing the non-invasive evaluation of congenital and acquired large airway disorders in children. For example, the faster scanning time and increased anatomical coverage that are afforded by MDCT are especially beneficial to children. MDCT also provides high-quality multiplanar 2-dimensional (2-D), internal and external volume-rendering 3-dimensional (3-D), and dynamic 4-dimensional (4-D) imaging. These advances have enabled CT to become the primary non-invasive imaging modality of choice for the diagnosis, treatment planning, and follow-up evaluation of various large airway disorders in infants and children. It is thus essential for radiologists to be familiar with safe and effective techniques for performing MDCT and to be able to recognize the characteristic imaging appearances of large airway disorders affecting children. (orig.)

Image change detection systems, methods, and articles of manufacture

Science.gov (United States)

Jones, James L.; Lassahn, Gordon D.; Lancaster, Gregory D.

2010-01-05

Aspects of the invention relate to image change detection systems, methods, and articles of manufacture. According to one aspect, a method of identifying differences between a plurality of images is described. The method includes loading a source image and a target image into memory of a computer, constructing source and target edge images from the source and target images to enable processing of multiband images, displaying the source and target images on a display device of the computer, aligning the source and target edge images, switching displaying of the source image and the target image on the display device, to enable identification of differences between the source image and the target image.

Universal Image Steganalytic Method

Directory of Open Access Journals (Sweden)

V. Banoci

2014-12-01

Full Text Available In the paper we introduce a new universal steganalytic method in JPEG file format that is detecting well-known and also newly developed steganographic methods. The steganalytic model is trained by MHF-DZ steganographic algorithm previously designed by the same authors. The calibration technique with the Feature Based Steganalysis (FBS was employed in order to identify statistical changes caused by embedding a secret data into original image. The steganalyzer concept utilizes Support Vector Machine (SVM classification for training a model that is later used by the same steganalyzer in order to identify between a clean (cover and steganographic image. The aim of the paper was to analyze the variety in accuracy of detection results (ACR while detecting testing steganographic algorithms as F5, Outguess, Model Based Steganography without deblocking, JP Hide and Seek which represent the generally used steganographic tools. The comparison of four feature vectors with different lengths FBS (22, FBS (66 FBS(274 and FBS(285 shows promising results of proposed universal steganalytic method comparing to binary methods.

Using the MDCT thick slab MinIP method for the follow-up of pulmonary emphysema.

Science.gov (United States)

Lan, Hai; Nishitani, Hiromu; Nishihara, Sadamitsu; Ueno, Junji; Takao, Shoichiro; Iwamoto, Seiji; Kawanaka, Takashi; Mahmut, Mawlan; Qingge, Si

2011-08-01

The purpose of this study was to evaluate the usefulness of thick slab minimum intensity projection (MinIP) as a follow-up method in patients with pulmonary emphysema. This method was used to determine the presence or absence of changes over time in the lung field based on multi-detector-row CT (MDCT) data. Among patients diagnosed with pulmonary emphysema who underwent 16-MDCT (slice thickness, 1 mm) twice at an interval of 6 months or more, 12 patients without changes in the lung field and 14 with clear changes in the lung field were selected as subjects. An image interpretation experiment was performed by five image interpreters. Pulmonary emphysema was followed up using two types of thick slab MinIP (thick slab MinIP 1 and 2) and multi-planar reformation (MPR), and the results of image interpretation were evaluated by receiver operating characteristic (ROC) analysis. In addition, the time required for image interpretation was compared among the three follow-up methods. The area under the ROC curve (Az) was 0.794 for thick slab MinIP 1, 0.778 for the thick slab MinIP 2, and 0.759 for MPR, showing no significant differences among the three methods. Individual differences in each item were significantly more marked for MPR than for thick slab MinIP. The time required for image interpretation was around 18 seconds for thick slab MinIP 1, 11 seconds for thick slab MinIP 2, and approximately 127 seconds for MPR, showing significant differences among the three methods. There were no significant differences in the results of image interpretation regarding the presence or absence of changes in the lung fields between thick slab MinIP and MPR. However, thick slab MinIP showed a shorter image interpretation time and smaller individual differences in the results among image interpreters than MPR, suggesting the usefulness of this method for determining the presence or absence of changes with time in the lung fields of patients with pulmonary emphysema.

Handbook of mathematical methods in imaging

CERN Document Server

2015-01-01

The Handbook of Mathematical Methods in Imaging provides a comprehensive treatment of the mathematical techniques used in imaging science. The material is grouped into two central themes, namely, Inverse Problems (Algorithmic Reconstruction) and Signal and Image Processing. Each section within the themes covers applications (modeling), mathematics, numerical methods (using a case example) and open questions. Written by experts in the area, the presentation is mathematically rigorous. This expanded and revised second edition contains updates to existing chapters and 16 additional entries on important mathematical methods such as graph cuts, morphology, discrete geometry, PDEs, conformal methods, to name a few. The entries are cross-referenced for easy navigation through connected topics. Available in both print and electronic forms, the handbook is enhanced by more than 200 illustrations and an extended bibliography. It will benefit students, scientists and researchers in applied mathematics. Engineers and com...

Computational methods in molecular imaging technologies

CERN Document Server

Gunjan, Vinit Kumar; Venkatesh, C; Amarnath, M

2017-01-01

This book highlights the experimental investigations that have been carried out on magnetic resonance imaging and computed tomography (MRI & CT) images using state-of-the-art Computational Image processing techniques, and tabulates the statistical values wherever necessary. In a very simple and straightforward way, it explains how image processing methods are used to improve the quality of medical images and facilitate analysis. It offers a valuable resource for researchers, engineers, medical doctors and bioinformatics experts alike.

[Multimodal medical image registration using cubic spline interpolation method].

Science.gov (United States)

He, Yuanlie; Tian, Lianfang; Chen, Ping; Wang, Lifei; Ye, Guangchun; Mao, Zongyuan

2007-12-01

Based on the characteristic of the PET-CT multimodal image series, a novel image registration and fusion method is proposed, in which the cubic spline interpolation method is applied to realize the interpolation of PET-CT image series, then registration is carried out by using mutual information algorithm and finally the improved principal component analysis method is used for the fusion of PET-CT multimodal images to enhance the visual effect of PET image, thus satisfied registration and fusion results are obtained. The cubic spline interpolation method is used for reconstruction to restore the missed information between image slices, which can compensate for the shortage of previous registration methods, improve the accuracy of the registration, and make the fused multimodal images more similar to the real image. Finally, the cubic spline interpolation method has been successfully applied in developing 3D-CRT (3D Conformal Radiation Therapy) system.

The application of spiral-CT and 3D-imaging of airway for observation of efficacy and complication after tracheobronchial stent placement

International Nuclear Information System (INIS)

Wei Ning; Xu Hao; Zu Maoheng; Gu Yuming; Li Gang; Zhang Qingqiao; Xu Wei; Cui Yanfeng; Liu Hongtao; Wang Wenliang

2012-01-01

Objective: To evaluate the application of spiral-CT and 3D-imaging of airway for observation of efficacy and complication after tracheobronchial stent placement. Methods: Thirty-one patients treated with tracheal stents were retrospectively analyzed, of which there were 27 malignant tracheal stenosis, 2 benign tracheal stenosis, 1 bronchial remnant fistula and 1 gastroesophageal anastomosis tracheal fistula. The spiral-CT and 3D-imagings were analyzed and the location, shape and complication of the stents were assessed. Results: Thirty-one patients were treated with 8 Z-type stainless steel stents and 28 Ni-Ti memory alloy stents. The stents of 22 cases remained patent in the original position and restenosis was occurred in 5 cases, migration in 3 cases and fracture in 1 case. All the CT features were performed and reconstructed on the workstation, using multiplanar reconstruction, volume rendering, and CT virtual endoscopy. The location of tracheal stenosis and fistula were showed in different angle, and the location, shape of the stents, and the complications (such as restenosis, fracture) as well. Conclusion: Spiral-CT and 3D-imaging is a rapid, simple and effective method in assessing tracheal stent implantation and complication, therefore, it is of great value in clinical practice. (authors)

Methods of filtering the graph images of the functions

Directory of Open Access Journals (Sweden)

Олександр Григорович Бурса

2017-06-01

Full Text Available The theoretical aspects of cleaning raster images of scanned graphs of functions from digital, chromatic and luminance distortions by using computer graphics techniques have been considered. The basic types of distortions characteristic of graph images of functions have been stated. To suppress the distortion several methods, providing for high-quality of the resulting images and saving their topological features, were suggested. The paper describes the techniques developed and improved by the authors: the method of cleaning the image of distortions by means of iterative contrasting, based on the step-by-step increase in image contrast in the graph by 1%; the method of small entities distortion restoring, based on the thinning of the known matrix of contrast increase filter (the allowable dimensions of the nucleus dilution radius convolution matrix, which provide for the retention of the graph lines have been established; integration technique of the noise reduction method by means of contrasting and distortion restoring method of small entities with known σ-filter. Each method in the complex has been theoretically substantiated. The developed methods involve treatment of graph images as the entire image (global processing and its fragments (local processing. The metrics assessing the quality of the resulting image with the global and local processing have been chosen, the substantiation of the choice as well as the formulas have been given. The proposed complex methods of cleaning the graphs images of functions from grayscale image distortions is adaptive to the form of an image carrier, the distortion level in the image and its distribution. The presented results of testing the developed complex of methods for a representative sample of images confirm its effectiveness

INTEGRATED FUSION METHOD FOR MULTIPLE TEMPORAL-SPATIAL-SPECTRAL IMAGES

Directory of Open Access Journals (Sweden)

H. Shen

2012-08-01

Full Text Available Data fusion techniques have been widely researched and applied in remote sensing field. In this paper, an integrated fusion method for remotely sensed images is presented. Differently from the existed methods, the proposed method has the performance to integrate the complementary information in multiple temporal-spatial-spectral images. In order to represent and process the images in one unified framework, two general image observation models are firstly presented, and then the maximum a posteriori (MAP framework is used to set up the fusion model. The gradient descent method is employed to solve the fused image. The efficacy of the proposed method is validated using simulated images.

Images Encryption Method using Steganographic LSB Method, AES and RSA algorithm

Science.gov (United States)

Moumen, Abdelkader; Sissaoui, Hocine

2017-03-01

Vulnerability of communication of digital images is an extremely important issue nowadays, particularly when the images are communicated through insecure channels. To improve communication security, many cryptosystems have been presented in the image encryption literature. This paper proposes a novel image encryption technique based on an algorithm that is faster than current methods. The proposed algorithm eliminates the step in which the secrete key is shared during the encryption process. It is formulated based on the symmetric encryption, asymmetric encryption and steganography theories. The image is encrypted using a symmetric algorithm, then, the secret key is encrypted by means of an asymmetrical algorithm and it is hidden in the ciphered image using a least significant bits steganographic scheme. The analysis results show that while enjoying the faster computation, our method performs close to optimal in terms of accuracy.

A new method for mobile phone image denoising

Science.gov (United States)

Jin, Lianghai; Jin, Min; Li, Xiang; Xu, Xiangyang

2015-12-01

Images captured by mobile phone cameras via pipeline processing usually contain various kinds of noises, especially granular noise with different shapes and sizes in both luminance and chrominance channels. In chrominance channels, noise is closely related to image brightness. To improve image quality, this paper presents a new method to denoise such mobile phone images. The proposed scheme converts the noisy RGB image to luminance and chrominance images, which are then denoised by a common filtering framework. The common filtering framework processes a noisy pixel by first excluding the neighborhood pixels that significantly deviate from the (vector) median and then utilizing the other neighborhood pixels to restore the current pixel. In the framework, the strength of chrominance image denoising is controlled by image brightness. The experimental results show that the proposed method obviously outperforms some other representative denoising methods in terms of both objective measure and visual evaluation.

A comparative study on medical image segmentation methods

Directory of Open Access Journals (Sweden)

Praylin Selva Blessy SELVARAJ ASSLEY

2014-03-01

Full Text Available Image segmentation plays an important role in medical images. It has been a relevant research area in computer vision and image analysis. Many segmentation algorithms have been proposed for medical images. This paper makes a review on segmentation methods for medical images. In this survey, segmentation methods are divided into five categories: region based, boundary based, model based, hybrid based and atlas based. The five different categories with their principle ideas, advantages and disadvantages in segmenting different medical images are discussed.

Magnetic imager and method

Science.gov (United States)

Powell, James; Reich, Morris; Danby, Gordon

1997-07-22

A magnetic imager 10 includes a generator 18 for practicing a method of applying a background magnetic field over a concealed object, with the object being effective to locally perturb the background field. The imager 10 also includes a sensor 20 for measuring perturbations of the background field to detect the object. In one embodiment, the background field is applied quasi-statically. And, the magnitude or rate of change of the perturbations may be measured for determining location, size, and/or condition of the object.

Meningiomas parasselares: aspectos na ressonância magnética Parasellar meningiomas: magnetic resonance imaging findings

Directory of Open Access Journals (Sweden)

Alair Augusto S.M.D. dos Santos

2001-02-01

Full Text Available Foram revistos 22 casos de meningiomas parasselares avaliados por ressonância magnética em clínicas privadas nas cidades de Niterói e Rio de Janeiro, RJ. O objetivo deste trabalho é demonstrar os aspectos de imagem encontrados neste tumor. Os equipamentos utilizados tinham 0,5 e 1,0 Tesla, respectivamente, com aquisição de seqüências multiplanares ponderadas em T1 (antes e após a administração de gadolínio e em T2. Os sintomas principais foram cefaléia e alterações visuais, tendo apenas um caso cursado com hiperprolactinemia. O aspecto mais freqüente foi o de massa parasselar hipointensa em T1 e hiperintensa em T2, impregnando-se intensamente pelo gadolínio. A ressonância magnética é útil não apenas na demonstração da lesão mas, sobretudo, na avaliação do comprometimento das estruturas vizinhas, especialmente do seio cavernoso, o que explica as alterações visuais encontradas.We reviewed 22 cases of patients with parasellar meningiomas evaluated with magnetic resonance imaging (MRI in private clinics of the cities of Niterói and Rio de Janeiro, RJ, Brazil. Our aim was to characterize the imaging findings in this type of tumor. MRI scanners with 0.5 and 1.0 Tesla magnets were used for the acquisition of multiplanar T1-weighted (pre- and post-gadolinium administration and T2-weighted images. The main symptoms observed were headache and visual disturbances. Hyperprolactinemia was observed in only one patient. The most frequent imaging finding was a parasellar mass which appeared hypointense on T1-weighted and hyperintense on T2-weighted images, and enhanced intensively after gadolinium administration. MRI is useful to demonstrate the lesion and to assess the damage to adjacent structures, particularly when the patient presents visual disturbances due to involvement of the cavernous sinuses.

Reliable clarity automatic-evaluation method for optical remote sensing images

Science.gov (United States)

Qin, Bangyong; Shang, Ren; Li, Shengyang; Hei, Baoqin; Liu, Zhiwen

2015-10-01

Image clarity, which reflects the sharpness degree at the edge of objects in images, is an important quality evaluate index for optical remote sensing images. Scholars at home and abroad have done a lot of work on estimation of image clarity. At present, common clarity-estimation methods for digital images mainly include frequency-domain function methods, statistical parametric methods, gradient function methods and edge acutance methods. Frequency-domain function method is an accurate clarity-measure approach. However, its calculation process is complicate and cannot be carried out automatically. Statistical parametric methods and gradient function methods are both sensitive to clarity of images, while their results are easy to be affected by the complex degree of images. Edge acutance method is an effective approach for clarity estimate, while it needs picking out the edges manually. Due to the limits in accuracy, consistent or automation, these existing methods are not applicable to quality evaluation of optical remote sensing images. In this article, a new clarity-evaluation method, which is based on the principle of edge acutance algorithm, is proposed. In the new method, edge detection algorithm and gradient search algorithm are adopted to automatically search the object edges in images. Moreover, The calculation algorithm for edge sharpness has been improved. The new method has been tested with several groups of optical remote sensing images. Compared with the existing automatic evaluation methods, the new method perform better both in accuracy and consistency. Thus, the new method is an effective clarity evaluation method for optical remote sensing images.

Finite element formulation for a digital image correlation method

International Nuclear Information System (INIS)

Sun Yaofeng; Pang, John H. L.; Wong, Chee Khuen; Su Fei

2005-01-01

A finite element formulation for a digital image correlation method is presented that will determine directly the complete, two-dimensional displacement field during the image correlation process on digital images. The entire interested image area is discretized into finite elements that are involved in the common image correlation process by use of our algorithms. This image correlation method with finite element formulation has an advantage over subset-based image correlation methods because it satisfies the requirements of displacement continuity and derivative continuity among elements on images. Numerical studies and a real experiment are used to verify the proposed formulation. Results have shown that the image correlation with the finite element formulation is computationally efficient, accurate, and robust

Method of orthogonally splitting imaging pose measurement

Science.gov (United States)

Zhao, Na; Sun, Changku; Wang, Peng; Yang, Qian; Liu, Xintong

2018-01-01

In order to meet the aviation's and machinery manufacturing's pose measurement need of high precision, fast speed and wide measurement range, and to resolve the contradiction between measurement range and resolution of vision sensor, this paper proposes an orthogonally splitting imaging pose measurement method. This paper designs and realizes an orthogonally splitting imaging vision sensor and establishes a pose measurement system. The vision sensor consists of one imaging lens, a beam splitter prism, cylindrical lenses and dual linear CCD. Dual linear CCD respectively acquire one dimensional image coordinate data of the target point, and two data can restore the two dimensional image coordinates of the target point. According to the characteristics of imaging system, this paper establishes the nonlinear distortion model to correct distortion. Based on cross ratio invariability, polynomial equation is established and solved by the least square fitting method. After completing distortion correction, this paper establishes the measurement mathematical model of vision sensor, and determines intrinsic parameters to calibrate. An array of feature points for calibration is built by placing a planar target in any different positions for a few times. An terative optimization method is presented to solve the parameters of model. The experimental results show that the field angle is 52 °, the focus distance is 27.40 mm, image resolution is 5185×5117 pixels, displacement measurement error is less than 0.1mm, and rotation angle measurement error is less than 0.15°. The method of orthogonally splitting imaging pose measurement can satisfy the pose measurement requirement of high precision, fast speed and wide measurement range.

Congenital frontonasal masses: developmental anatomy, malformations, and MR imaging

Energy Technology Data Exchange (ETDEWEB)

Hedlund, Gary [Primary Children' s Medical Center, Department of Medical Imaging, Salt Lake City, UT (United States)

2006-07-15

The newborn, infant, or young child who presents with a midline frontonasal mass often poses a diagnostic challenge to the clinician. The most pressing issue is whether the mass extends intracranially. The development of the frontonasal region or anterior neuropore is complex. Aberrant embryogenesis leads to three main types of anomalies: nasal dermal sinus, anterior cephalocele, and nasal glioma. Understanding the developmental anatomy of the anterior neuropore and postnatal maturation will serve the radiologist well when it comes to imaging frontonasal masses. Pitfalls particularly common to CT imaging interpretation include the evolving ossification of the frontal, nasal and ethmoid bones in the first year of life, morphology and size of the foramen cecum, and the natural intumescence of the anterior nasal septum. Determination of the presence of a connection between the frontonasal mass and the anterior cranial fossae is crucial in the imaging assessment and clinical management. In the case of the nasal dermal sinus, failure to appreciate the intracranial components of the malformation can lead to fatal meningitis. MR imaging is the modality of choice for assessing the pediatric frontonasal region. Its advantages include multiplanar imaging, distinguishing the interface among cartilage, bone, brain and fluid, diffusion imaging to detect epidermoid tumors, and the capacity to evaluate the brain for associated cerebral anomalies. (orig.)

Contrast-enhanced CISS imaging of cerebellopontine angle tumors

Energy Technology Data Exchange (ETDEWEB)

Tozaki, Mitsuhiro; Toyoda, Keiko; Hata, Yuichi; Fukuda, Yasushi; Fukuda, Kunihiko [Jikei Univ., Tokyo (Japan). School of Medicine; Katano, Shuichi

1999-10-01

Our purpose of this study was to evaluate the clinical usefulness of contrast-enhanced CISS-3DFT MR imaging for the diagnosis of CP angle tumors. CISS-3DFT MR imaging is expected for screening procedure of acoustic schwannoma because of excellent spatial resolution. Recently, we discovered contrast enhancement effect on CISS sequence in spite of heavily T{sub 2}-weighted images. Fourteen patients with CP angle tumors were performed on a 1.0 T MR unit. Transaxial CISS-3DFT MRI was obtained both before and after intravenous injections of Gd-DTPA. Multiplanar reconstructions (MPRs) were performed in all cases. Contrast enhancement effect of CP angle tumors, and the relationship between tumors and the adjacent cranial nerves were evaluated. Contrast enhancement effect of the tumors was present in all cases in spite of heavily T{sub 2}-weighted images of CISS sequences. In the internal auditory canal, relationship between the tumors and the cranial nerves was demonstrated in 6 cases (6/9). In the cerebellopontine cistern, all cases were demonstrated (11/11). Contrast-enhanced CISS-3DFT MR imaging with a good contrast resolution and an excellent spatial resolution is useful for the diagnosis of CP angle tumors. (author)

Matrix-based image reconstruction methods for tomography

International Nuclear Information System (INIS)

Llacer, J.; Meng, J.D.

1984-10-01

Matrix methods of image reconstruction have not been used, in general, because of the large size of practical matrices, ill condition upon inversion and the success of Fourier-based techniques. An exception is the work that has been done at the Lawrence Berkeley Laboratory for imaging with accelerated radioactive ions. An extension of that work into more general imaging problems shows that, with a correct formulation of the problem, positron tomography with ring geometries results in well behaved matrices which can be used for image reconstruction with no distortion of the point response in the field of view and flexibility in the design of the instrument. Maximum Likelihood Estimator methods of reconstruction, which use the system matrices tailored to specific instruments and do not need matrix inversion, are shown to result in good preliminary images. A parallel processing computer structure based on multiple inexpensive microprocessors is proposed as a system to implement the matrix-MLE methods. 14 references, 7 figures

Magnetic resonance imaging of the shoulder

International Nuclear Information System (INIS)

Ilieva, E.

2015-01-01

Full text: Magnetic resonance imaging (MRI) is an excellent non-invasive imaging tool that can complement the physical examination in the evaluation of traumatic and non-traumatic injuries of the shoulder. The superb soft tissue contrast and multiplanar capabilities of MRI make it a preferred modality to provide a global assessment of the soft tissue and osseous structures of the shoulder. Learning objectives: to review briefly the anatomy of the shoulder and the specificity of sequences and planes for MRI; to demonstrate the characteristic MR findings of some of the most common shoulder disorders; to indicate how MR arthrography (MRA) of the shoulder can add extra value to the diagnostic process; to outline a systematic approach to the interpretation of the shoulder MR examination. Choosing the most suitable sequences and planes as well as the thorough knowledge of the anatomic structures assist the correct diagnosis of the pathologic disorders of the shoulder which is of great importance for the precise treatment management, surgical versus conservative, as well as for the appropriate surgical approach, open versus arthroscopic

Generalized Row-Action Methods for Tomographic Imaging

DEFF Research Database (Denmark)

Andersen, Martin Skovgaard; Hansen, Per Christian

2014-01-01

Row-action methods play an important role in tomographic image reconstruction. Many such methods can be viewed as incremental gradient methods for minimizing a sum of a large number of convex functions, and despite their relatively poor global rate of convergence, these methods often exhibit fast...... initial convergence which is desirable in applications where a low-accuracy solution is acceptable. In this paper, we propose relaxed variants of a class of incremental proximal gradient methods, and these variants generalize many existing row-action methods for tomographic imaging. Moreover, they allow...

Influence of model based iterative reconstruction algorithm on image quality of multiplanar reformations in reduced dose chest CT

International Nuclear Information System (INIS)

Barras, Heloise; Dunet, Vincent; Hachulla, Anne-Lise; Grimm, Jochen; Beigelman-Aubry, Catherine

2016-01-01

Model-based iterative reconstruction (MBIR) reduces image noise and improves image quality (IQ) but its influence on post-processing tools including maximal intensity projection (MIP) and minimal intensity projection (mIP) remains unknown. To evaluate the influence on IQ of MBIR on native, mIP, MIP axial and coronal reformats of reduced dose computed tomography (RD-CT) chest acquisition. Raw data of 50 patients, who underwent a standard dose CT (SD-CT) and a follow-up RD-CT with a CT dose index (CTDI) of 2–3 mGy, were reconstructed by MBIR and FBP. Native slices, 4-mm-thick MIP, and 3-mm-thick mIP axial and coronal reformats were generated. The relative IQ, subjective IQ, image noise, and number of artifacts were determined in order to compare different reconstructions of RD-CT with reference SD-CT. The lowest noise was observed with MBIR. RD-CT reconstructed by MBIR exhibited the best relative and subjective IQ on coronal view regardless of the post-processing tool. MBIR generated the lowest rate of artefacts on coronal mIP/MIP reformats and the highest one on axial reformats, mainly represented by distortions and stairsteps artifacts. The MBIR algorithm reduces image noise but generates more artifacts than FBP on axial mIP and MIP reformats of RD-CT. Conversely, it significantly improves IQ on coronal views, without increasing artifacts, regardless of the post-processing technique

Hyperspectral image compressing using wavelet-based method

Science.gov (United States)

Yu, Hui; Zhang, Zhi-jie; Lei, Bo; Wang, Chen-sheng

2017-10-01

Hyperspectral imaging sensors can acquire images in hundreds of continuous narrow spectral bands. Therefore each object presented in the image can be identified from their spectral response. However, such kind of imaging brings a huge amount of data, which requires transmission, processing, and storage resources for both airborne and space borne imaging. Due to the high volume of hyperspectral image data, the exploration of compression strategies has received a lot of attention in recent years. Compression of hyperspectral data cubes is an effective solution for these problems. Lossless compression of the hyperspectral data usually results in low compression ratio, which may not meet the available resources; on the other hand, lossy compression may give the desired ratio, but with a significant degradation effect on object identification performance of the hyperspectral data. Moreover, most hyperspectral data compression techniques exploits the similarities in spectral dimensions; which requires bands reordering or regrouping, to make use of the spectral redundancy. In this paper, we explored the spectral cross correlation between different bands, and proposed an adaptive band selection method to obtain the spectral bands which contain most of the information of the acquired hyperspectral data cube. The proposed method mainly consist three steps: First, the algorithm decomposes the original hyperspectral imagery into a series of subspaces based on the hyper correlation matrix of the hyperspectral images between different bands. And then the Wavelet-based algorithm is applied to the each subspaces. At last the PCA method is applied to the wavelet coefficients to produce the chosen number of components. The performance of the proposed method was tested by using ISODATA classification method.

Imaging and treatment of a fracture of the hamate bone

International Nuclear Information System (INIS)

Andresen, R.; Radmer, S.; Scheufler, O.; Banzer, D.

2001-01-01

The relatively rare fractures of the hamate bone are the most common osseous injuries of the distal carpal row, whereby fractures of both the body and the hook of the hamate occur. We present a hamulus ossis hamati fracture that was caused by direct trauma in a high-level game of underwater rugby. Although this was diagnosed by conventional X-ray, the precise position of the fracture was clearly imaged using thin-layer CT, while additional multiplanar MRT revealed further sequelae of the trauma. A CT follow-up after 10 weeks of conservative therapy did not show any osseous consolidation, which indicated the need for surgical revision with exstirpation of the hamulus. (orig.) [de

3D Seismic Imaging using Marchenko Methods

Science.gov (United States)

Lomas, A.; Curtis, A.

2017-12-01

Marchenko methods are novel, data driven techniques that allow seismic wavefields from sources and receivers on the Earth's surface to be redatumed to construct wavefields with sources in the subsurface - including complex multiply-reflected waves, and without the need for a complex reference model. In turn, this allows subsurface images to be constructed at any such subsurface redatuming points (image or virtual receiver points). Such images are then free of artefacts from multiply-scattered waves that usually contaminate migrated seismic images. Marchenko algorithms require as input the same information as standard migration methods: the full reflection response from sources and receivers at the Earth's surface, and an estimate of the first arriving wave between the chosen image point and the surface. The latter can be calculated using a smooth velocity model estimated using standard methods. The algorithm iteratively calculates a signal that focuses at the image point to create a virtual source at that point, and this can be used to retrieve the signal between the virtual source and the surface. A feature of these methods is that the retrieved signals are naturally decomposed into up- and down-going components. That is, we obtain both the signal that initially propagated upwards from the virtual source and arrived at the surface, separated from the signal that initially propagated downwards. Figure (a) shows a 3D subsurface model with a variable density but a constant velocity (3000m/s). Along the surface of this model (z=0) in both the x and y directions are co-located sources and receivers at 20-meter intervals. The redatumed signal in figure (b) has been calculated using Marchenko methods from a virtual source (1200m, 500m and 400m) to the surface. For comparison the true solution is given in figure (c), and shows a good match when compared to figure (b). While these 2D redatuming and imaging methods are still in their infancy having first been developed in

THE EFFECT OF IMAGE ENHANCEMENT METHODS DURING FEATURE DETECTION AND MATCHING OF THERMAL IMAGES

Directory of Open Access Journals (Sweden)

O. Akcay

2017-05-01

Full Text Available A successful image matching is essential to provide an automatic photogrammetric process accurately. Feature detection, extraction and matching algorithms have performed on the high resolution images perfectly. However, images of cameras, which are equipped with low-resolution thermal sensors are problematic with the current algorithms. In this paper, some digital image processing techniques were applied to the low-resolution images taken with Optris PI 450 382 x 288 pixel optical resolution lightweight thermal camera to increase extraction and matching performance. Image enhancement methods that adjust low quality digital thermal images, were used to produce more suitable images for detection and extraction. Three main digital image process techniques: histogram equalization, high pass and low pass filters were considered to increase the signal-to-noise ratio, sharpen image, remove noise, respectively. Later on, the pre-processed images were evaluated using current image detection and feature extraction methods Maximally Stable Extremal Regions (MSER and Speeded Up Robust Features (SURF algorithms. Obtained results showed that some enhancement methods increased number of extracted features and decreased blunder errors during image matching. Consequently, the effects of different pre-process techniques were compared in the paper.

Organization and visualization of medical images in radiotherapy

International Nuclear Information System (INIS)

Lorang, T.

2001-05-01

In modern radiotherapy, various imaging equipment is used to acquire views from inside human bodies. Tomographic imaging equipment is acquiring stacks of cross-sectional images, software implementations derive three-dimensional volumes from planar images to allow for visualization of reconstructed cross-sections at any orientation and location and higher-level visualization systems allow for transparent views and surface rendering. Of upcoming interest in radiotherapy is mutual information, the integration of information from multiple imaging equipment res. from the same imaging equipment at different time stamps and varying acquisition parameters. Huge amounts of images are acquired nowadays at radiotherapy centers, requiring organization of images with respect to patient, acquisition and equipment to allow for visualization of images in a comparative and integrative manner. Especially for integration of image information from different equipment, geometrical information is required to allow for registration of images res. volumes. DICOM 3.0 has been introduced as a standard for information interchange with respect to medical imaging. Geometric information of cross-sections, demographic information of patients and medical information of acquisitions and equipment are covered by this standard, allowing for a high-level automation with respect to organization and visualization of medical images. Reconstructing cross-sectional images from volumes at any orientation and location is required for the purpose of registration and multi-planar views. Resampling and addressing of discrete volume data need be implemented efficiently to allow for simultaneous visualization of multiple cross-sectional images, especially with respect to multiple, non-isotropy volume data sets. (author)

Does thorax EIT image analysis depend on the image reconstruction method?

Science.gov (United States)

Zhao, Zhanqi; Frerichs, Inéz; Pulletz, Sven; Müller-Lisse, Ullrich; Möller, Knut

2013-04-01

Different methods were proposed to analyze the resulting images of electrical impedance tomography (EIT) measurements during ventilation. The aim of our study was to examine if the analysis methods based on back-projection deliver the same results when applied on images based on other reconstruction algorithms. Seven mechanically ventilated patients with ARDS were examined by EIT. The thorax contours were determined from the routine CT images. EIT raw data was reconstructed offline with (1) filtered back-projection with circular forward model (BPC); (2) GREIT reconstruction method with circular forward model (GREITC) and (3) GREIT with individual thorax geometry (GREITT). Three parameters were calculated on the resulting images: linearity, global ventilation distribution and regional ventilation distribution. The results of linearity test are 5.03±2.45, 4.66±2.25 and 5.32±2.30 for BPC, GREITC and GREITT, respectively (median ±interquartile range). The differences among the three methods are not significant (p = 0.93, Kruskal-Wallis test). The proportions of ventilation in the right lung are 0.58±0.17, 0.59±0.20 and 0.59±0.25 for BPC, GREITC and GREITT, respectively (p = 0.98). The differences of the GI index based on different reconstruction methods (0.53±0.16, 0.51±0.25 and 0.54±0.16 for BPC, GREITC and GREITT, respectively) are also not significant (p = 0.93). We conclude that the parameters developed for images generated with GREITT are comparable with filtered back-projection and GREITC.

Epidemiology, imaging, and treatment of Lisfranc fracture-dislocations revisited

International Nuclear Information System (INIS)

Kalia, Vivek; Fishman, Elliot K.; Carrino, John A.; Fayad, Laura M.

2012-01-01

The purpose of this article is to discuss the features of Lisfranc injuries and identify their typical imaging findings on radiographs, CT, and MR imaging. Lisfranc injuries are most often caused by hyperplantarflexion of the foot, often during a sporting injury or in high-speed motor vehicle collisions. The most common radiographic findings include diastasis of the base of the first and second metatarsals and the ''fleck'' sign, though neither is necessarily present in every Lisfranc fracture-dislocation. Owing to their often subtle radiographic presentation, clinically suspected Lisfranc injuries warrant imaging with a more sensitive test for the detection of osseous and ligamentous Lisfranc injuries. 3D CT imaging provides a comprehensive evaluation of the injury for optimal treatment planning, with resultant decreased long-term patient morbidity. Furthermore, 3D volume-rendered CT and CT multiplanar reconstructions (MPRs) provide osseous and neurovascular anatomic detail that may be a considerable help with surgical planning for operative cases of Lisfranc injuries. Also, with 3D CT and MPRs, other occult fractures, which are common in patients with high-energy injury and multiple trauma, may become evident. (orig.)

Methods of producing luminescent images

International Nuclear Information System (INIS)

Broadhead, P.; Newman, G.A.

1977-01-01

A method is described for producing a luminescent image in a layer of a binding material in which is dispersed a thermoluminescent material. The layer is heated uniformly to a temperature of 80 to 300 0 C and is exposed to luminescence inducing radiation whilst so heated. The preferred exposing radiation is X-rays and preferably the thermoluminescent material is insensitive to electromagnetic radiation of wavelength longer than 300 mm. Information concerning preparation of the luminescent material is given in BP 1,347,672; this material has the advantage that at elevated temperatures it shows increased sensitivity compared with room temperature. At temperatures in the range 80 to 150 0 C the thermoluminescent material exhibits 'afterglow', allowing the image to persist for several seconds after the X-radiation has ceased, thus allowing the image to be retained for visual inspection in this temperature range. At higher temperatures, however, there is negligible 'afterglow'. The thermoluminescent layers so produced are particularly useful as fluoroscopic screens. The preferred method of heating the thermoluminescent material is described in BP 1,354,149. An example is given of the application of the method. (U.K.)

Mathematical methods in elasticity imaging

CERN Document Server

Ammari, Habib; Garnier, Josselin; Kang, Hyeonbae; Lee, Hyundae; Wahab, Abdul

2015-01-01

This book is the first to comprehensively explore elasticity imaging and examines recent, important developments in asymptotic imaging, modeling, and analysis of deterministic and stochastic elastic wave propagation phenomena. It derives the best possible functional images for small inclusions and cracks within the context of stability and resolution, and introduces a topological derivative-based imaging framework for detecting elastic inclusions in the time-harmonic regime. For imaging extended elastic inclusions, accurate optimal control methodologies are designed and the effects of uncertainties of the geometric or physical parameters on stability and resolution properties are evaluated. In particular, the book shows how localized damage to a mechanical structure affects its dynamic characteristics, and how measured eigenparameters are linked to elastic inclusion or crack location, orientation, and size. Demonstrating a novel method for identifying, locating, and estimating inclusions and cracks in elastic...

Accelerated gradient methods for constrained image deblurring

International Nuclear Information System (INIS)

Bonettini, S; Zanella, R; Zanni, L; Bertero, M

2008-01-01

In this paper we propose a special gradient projection method for the image deblurring problem, in the framework of the maximum likelihood approach. We present the method in a very general form and we give convergence results under standard assumptions. Then we consider the deblurring problem and the generality of the proposed algorithm allows us to add a energy conservation constraint to the maximum likelihood problem. In order to improve the convergence rate, we devise appropriate scaling strategies and steplength updating rules, especially designed for this application. The effectiveness of the method is evaluated by means of a computational study on astronomical images corrupted by Poisson noise. Comparisons with standard methods for image restoration, such as the expectation maximization algorithm, are also reported.

Quantitative evaluation of small breast masses using a compartment model analysis on dynamic MR imaging

Energy Technology Data Exchange (ETDEWEB)

Ikeda, Osamu; Morishita, Shoji; Kido, Taeko; Kitajima, Mika; Okamura, Kenji; Fukuda, Seiji [Kumamoto Rosai Hospital, Yatsushiro (Japan); Yamashita, Yasuyuki; Takahashi, Mutsumasa

1998-07-01

To differentiate between malignant and benign breast masses using a compartmental analysis, 55 patients with breast masses (fibroadenoma, n=22; invasive ductal carcinoma, n=29; noninvasive ductal carcinoma, n=8) underwent Gd-DTPA enhanced dynamic MR imaging. Dynamic MR images obtained using two-dimensional fat-saturated fast multiplanar corrupted gradient echo technique over 10 minutes following bolus injection of Gd-DTPA. The triexponential concentration curve of Gd-DTPA was fitted to a theoretical model based on compartmental analysis. Using this method, the transfer constant (or permeability surface product per unit volume of component k) and f{sub 3}/f{sub 1}=f were measured, where f{sub 1} represents tumor vessel volume and f{sub 3} represents extracellular volume. The k value was significantly greater (p<0.01) for malignant tumors, and the k value seen in cases of noninvasive ductal carcinoma was less than that for invasive ductal carcinoma. The f value was significantly smaller (p<0.01) for malignant tumors, whereas the f value for noninvasive ductal carcinoma was not significantly different from that for invasive ductal carcinoma. We believe that this type of compartmental analysis may be of value for the evaluation of breast masses. (author)

FUSION SEGMENTATION METHOD BASED ON FUZZY THEORY FOR COLOR IMAGES

Directory of Open Access Journals (Sweden)

J. Zhao

2017-09-01

Full Text Available The image segmentation method based on two-dimensional histogram segments the image according to the thresholds of the intensity of the target pixel and the average intensity of its neighborhood. This method is essentially a hard-decision method. Due to the uncertainties when labeling the pixels around the threshold, the hard-decision method can easily get the wrong segmentation result. Therefore, a fusion segmentation method based on fuzzy theory is proposed in this paper. We use membership function to model the uncertainties on each color channel of the color image. Then, we segment the color image according to the fuzzy reasoning. The experiment results show that our proposed method can get better segmentation results both on the natural scene images and optical remote sensing images compared with the traditional thresholding method. The fusion method in this paper can provide new ideas for the information extraction of optical remote sensing images and polarization SAR images.

An attenuation correction method for PET/CT images

International Nuclear Information System (INIS)

Ue, Hidenori; Yamazaki, Tomohiro; Haneishi, Hideaki

2006-01-01

In PET/CT systems, accurate attenuation correction can be achieved by creating an attenuation map from an X-ray CT image. On the other hand, respiratory-gated PET acquisition is an effective method for avoiding motion blurring of the thoracic and abdominal organs caused by respiratory motion. In PET/CT systems employing respiratory-gated PET, using an X-ray CT image acquired during breath-holding for attenuation correction may have a large effect on the voxel values, especially in regions with substantial respiratory motion. In this report, we propose an attenuation correction method in which, as the first step, a set of respiratory-gated PET images is reconstructed without attenuation correction, as the second step, the motion of each phase PET image from the PET image in the same phase as the CT acquisition timing is estimated by the previously proposed method, as the third step, the CT image corresponding to each respiratory phase is generated from the original CT image by deformation according to the motion vector maps, and as the final step, attenuation correction using these CT images and reconstruction are performed. The effectiveness of the proposed method was evaluated using 4D-NCAT phantoms, and good stability of the voxel values near the diaphragm was observed. (author)

Multi-slice spiral CT multiplanar reconstruction findings of localized fat collection adjection to the subdiaphragmatic inferior vena cava

International Nuclear Information System (INIS)

Cao Hetao; Lu Jian; Zhao Jinli; Liu Tingting; Qin Jufeng; Xu Wen; Qin Jiangchun; Jiang Junkang

2012-01-01

Objective: To discusses the MSCT multiplanar reconstruction manifestation (MPR) of localized fat collection adjection to subdiaphragmatic inferior vena cava (IVC fat ). Methods: The thoracic and abdominal MSCT scan data of 8246 patients were browsed,45 patients with presumed IVC fat on axial CT scans were further studied prospectively with MSCT MPR. The predisposing position of IVC fat and its relationship with IVC were observed. It was divided into two kinds of intraluminal type and extraluminal type according to the angle of IVC fat with respect of the wall of IVC.The other 50 patients without IVC fat were randomly selected as the control group. The sagittal inclination angle (SIA) and diameter ratio (DR) between supra- and sub-diaphragmatic IVC between the two groups were compared by using t test. Results: The detection rate was 0.55% (45/8246). Of which hepatic vein lacuna 8 patients, subdiaphragmatic gap medial to IVC 28 patients and IVC groove 9 patients. The shape of IVC fat showed mainly for the round, oval and crescents on axial CT scans, of 15 patients intraluminal type, 4 showed 'target signs'. The shape of IVC fat showed mainly for 'half-moon' at MPR.The SIA and DR at IVC fat group were 21.62° ± 8.42° and 2.01 ±0.84 respectively, at control group were 16.75° ±7.82° (t=1.594, P>0.05) and 1.31 ±0.28 (t=2.341, P<0.05) respectively. Conclusion: The round, oval or half of limited fat density shadow adjection to subdiaphragmatic inferior vena cava which similar to in the lumen is the characteristic performance of IVC fat , it may be an anatomical variation. (authors)

W-transform method for feature-oriented multiresolution image retrieval

Energy Technology Data Exchange (ETDEWEB)

Kwong, M.K.; Lin, B. [Argonne National Lab., IL (United States). Mathematics and Computer Science Div.

1995-07-01

Image database management is important in the development of multimedia technology. Since an enormous amount of digital images is likely to be generated within the next few decades in order to integrate computers, television, VCR, cables, telephone and various imaging devices. Effective image indexing and retrieval systems are urgently needed so that images can be easily organized, searched, transmitted, and presented. Here, the authors present a local-feature-oriented image indexing and retrieval method based on Kwong, and Tang`s W-transform. Multiresolution histogram comparison is an effective method for content-based image indexing and retrieval. However, most recent approaches perform multiresolution analysis for whole images but do not exploit the local features present in the images. Since W-transform is featured by its ability to handle images of arbitrary size, with no periodicity assumptions, it provides a natural tool for analyzing local image features and building indexing systems based on such features. In this approach, the histograms of the local features of images are used in the indexing, system. The system not only can retrieve images that are similar or identical to the query images but also can retrieve images that contain features specified in the query images, even if the retrieved images as a whole might be very different from the query images. The local-feature-oriented method also provides a speed advantage over the global multiresolution histogram comparison method. The feature-oriented approach is expected to be applicable in managing large-scale image systems such as video databases and medical image databases.

Imaging method of brain surface anatomy structures using conventional T2-weighted MR images

International Nuclear Information System (INIS)

Hatanaka, Masahiko; Machida, Yoshio; Yoshida, Tadatoki; Katada, Kazuhiro.

1992-01-01

As a non-invasive technique for visualizing the brain surface structure by MRI, surface anatomy scanning (SAS) and the multislice SAS methods have been developed. Both techniques require additional MRI scanning to obtain images for the brain surface. In this paper, we report an alternative method to obtain the brain surface image using conventional T2-weighted multislice images without any additional scanning. The power calculation of the image pixel values, which is incorporated in the routine processing, has been applied in order to enhance the cerebrospinal fluid (CSF) contrast. We think that this method is one of practical approaches for imaging the surface anatomy of the brain. (author)

Method for nuclear magnetic resonance imaging

Science.gov (United States)

Kehayias, J.J.; Joel, D.D.; Adams, W.H.; Stein, H.L.

1988-05-26

A method for in vivo NMR imaging of the blood vessels and organs of a patient characterized by using a dark dye-like imaging substance consisting essentially of a stable, high-purity concentration of D/sub 2/O in a solution with water.

Maximum intensity projection MR angiography using shifted image data

International Nuclear Information System (INIS)

Machida, Yoshio; Ichinose, Nobuyasu; Hatanaka, Masahiko; Goro, Takehiko; Kitake, Shinichi; Hatta, Junicchi.

1992-01-01

The quality of MR angiograms has been significantly improved in past several years. Spatial resolution, however, is not sufficient for clinical use. On the other hand, MR image data can be filled at anywhere using Fourier shift theorem, and the quality of multi-planar reformed image has been reported to be improved remarkably using 'shifted data'. In this paper, we have clarified the efficiency of 'shifted data' for maximum intensity projection MR angiography. Our experimental studies and theoretical consideration showd that the quality of MR angiograms has been significantly improved using 'shifted data' as follows; 1) remarkable reduction of mosaic artifact, 2) improvement of spatial continuity for the blood vessels, and 3) reduction of variance for the signal intensity along the blood vessels. In other words, the angiograms looks much 'finer' than conventional ones, although the spatial resolution is not improved theoretically. Furthermore, we found the quality of MR angiograms dose not improve significantly with the 'shifted data' more than twice as dense as ordinal ones. (author)

CT of the musculoskeletal system: What is left is the days of MRI?

International Nuclear Information System (INIS)

West, A.T.H.; Marshall, T.J.; Bearcroft, P.W.

2009-01-01

Magnetic resonance imaging (MRI) plays a central role in the modern imaging of musculoskeletal disorders, due to its ability to produce multiplanar images and characterise soft tissues accurately. However, computed tomography (CT) still has an important role to play, not merely as an alternative to MRI, but as being the preferred imaging investigation in some situations. This article briefly reviews the history of CT technology, the technical factors involved and a number of current applications, as well as looking at future areas where CT may be employed. The advent of ever-increasing numbers of rows of detectors has opened up more possible uses for CT technology. However, diagnostic images may be obtained from CT systems with four rows of detectors or more, and their ability to produce near isotropic voxels and therefore multiplanar reformats. (orig.)

EXPRESS METHOD OF BARCODE GENERATION FROM FACIAL IMAGES

Directory of Open Access Journals (Sweden)

G. A. Kukharev

2014-03-01

Full Text Available In the paper a method of generating of standard type linear barcodes from facial images is proposed. The method is based on use of the histogram of facial image brightness, averaging the histogram on a limited number of intervals, quantization of results in a range of decimal numbers from 0 to 9 and table conversion into the final barcode. The proposed solution is computationally low-cost and not requires the use of specialized software on image processing that allows generating of facial barcodes in mobile systems, and thus the proposed method can be interpreted as an express method. Results of tests on the Face94 and CUHK Face Sketch FERET Databases showed that the proposed method is a new solution for use in the real-world practice and ensures the stability of generated barcodes in changes of scale, pose and mirroring of a facial image, and also changes of a facial expression and shadows on faces from local lighting. The proposed method is based on generating of a standard barcode directly from the facial image, and thus contains the subjective information about a person's face.

A distortion correction method for image intensifier and electronic portal images used in radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Ioannidis, G T; Geramani, K N; Zamboglou, N [Strahlenklinik, Stadtische Kliniken Offenbach, Offenbach (Germany); Uzunoglu, N [Department of Electrical and Computer Engineering, National Technical University of Athens, Athens (Greece)

1999-12-31

At the most of radiation departments a simulator and an `on line` verification system of the treated volume, in form of an electronic portal imaging device (EPID), are available. Networking and digital handling (saving, archiving etc.) of the image information is a necessity in the image processing procedures in order to evaluate verification and simulation recordings at the computer screen. Distortion is on the other hand prerequisite for quantitative comparison of both image modalities. Another limitation factor, in order to make quantitative assertions, is the fact that the irradiation fields in radiotherapy are usually bigger than the field of view of an image intensifier. Several segments of the irradiation field must therefore be acquired. Using pattern recognition techniques these segments can be composed into a single image. In this paper a distortion correction method will be presented. The method is based upon a well defined Grid which is embedded during the registration process on the image. The video signal from the image intensifier is acquired and processed. The grid is then recognised using image processing techniques. Ideally if all grid points are recognised, various methods can be applied in order to correct the distortion. But in practice this is not the case. Overlapping structures (bones etc.) have as a consequence that not all of the grid points can be recognised. Mathematical models from the Graph theory are applied in order to reconstruct the whole grid. The deviation of the grid points positions from the rated value is then used to calculate correction coefficients. This method (well defined grid, grid recognition, correction factors) can also be applied in verification images from the EPID or in other image modalities, and therefore a quantitative comparison in radiation treatment is possible. The distortion correction method and the application on simulator images will be presented. (authors)

Comparison of 3D cube FLAIR with 2D FLAIR for multiple sclerosis imaging at 3 tesla

Energy Technology Data Exchange (ETDEWEB)

Patzig, M.; Brueckmann, H.; Fesl, G. [Muenchen Univ. (Germany). Dept. of Neuroradiology; Burke, M. [GE Healthcare, Solingen (Germany)

2014-05-15

Purpose: Three-dimensional (3 D) MRI sequences allow improved spatial resolution with good signal and contrast properties as well as multiplanar reconstruction. We sought to compare Cube, a 3 D FLAIR sequence, to a standard 2 D FLAIR sequence in multiple sclerosis (MS) imaging. Materials and Methods: Examinations were performed in the clinical routine on a 3.0 Tesla scanner. 12 patients with definite MS were included. Lesions with MS-typical properties on the images of Cube FLAIR and 2 D FLAIR sequences were counted and allocated to different brain regions. Signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNR) were calculated. Results: With 384 the overall number of lesions found with Cube FLAIR was significantly higher than with 2 D FLAIR (N = 221). The difference was mostly accounted for by supratentorial lesions (N = 372 vs. N = 216) while the infratentorial lesion counts were low in both sequences. SNRs and CNRs were significantly higher in CUBE FLAIR with the exception of the CNR of lesion to gray matter, which was not significantly different. Conclusion: Cube FLAIR showed a higher sensitivity for MS lesions compared to a 2 D FLAIR sequence. 3 D FLAIR might replace 2 D FLAIR sequences in MS imaging in the future. (orig.)

A method for fast automated microscope image stitching.

Science.gov (United States)

Yang, Fan; Deng, Zhen-Sheng; Fan, Qiu-Hong

2013-05-01

Image stitching is an important technology to produce a panorama or larger image by combining several images with overlapped areas. In many biomedical researches, image stitching is highly desirable to acquire a panoramic image which represents large areas of certain structures or whole sections, while retaining microscopic resolution. In this study, we develop a fast normal light microscope image stitching algorithm based on feature extraction. At first, an algorithm of scale-space reconstruction of speeded-up robust features (SURF) was proposed to extract features from the images to be stitched with a short time and higher repeatability. Then, the histogram equalization (HE) method was employed to preprocess the images to enhance their contrast for extracting more features. Thirdly, the rough overlapping zones of the images preprocessed were calculated by phase correlation, and the improved SURF was used to extract the image features in the rough overlapping areas. Fourthly, the features were corresponded by matching algorithm and the transformation parameters were estimated, then the images were blended seamlessly. Finally, this procedure was applied to stitch normal light microscope images to verify its validity. Our experimental results demonstrate that the improved SURF algorithm is very robust to viewpoint, illumination, blur, rotation and zoom of the images and our method is able to stitch microscope images automatically with high precision and high speed. Also, the method proposed in this paper is applicable to registration and stitching of common images as well as stitching the microscope images in the field of virtual microscope for the purpose of observing, exchanging, saving, and establishing a database of microscope images. Copyright © 2013 Elsevier Ltd. All rights reserved.

Novel welding image processing method based on fractal theory

Institute of Scientific and Technical Information of China (English)

陈强; 孙振国; 肖勇; 路井荣

2002-01-01

Computer vision has come into used in the fields of welding process control and automation. In order to improve precision and rapidity of welding image processing, a novel method based on fractal theory has been put forward in this paper. Compared with traditional methods, the image is preliminarily processed in the macroscopic regions then thoroughly analyzed in the microscopic regions in the new method. With which, an image is divided up to some regions according to the different fractal characters of image edge, and the fuzzy regions including image edges are detected out, then image edges are identified with Sobel operator and curved by LSM (Lease Square Method). Since the data to be processed have been decreased and the noise of image has been reduced, it has been testified through experiments that edges of weld seam or weld pool could be recognized correctly and quickly.

Evaluation of processing methods for static radioisotope scan images

International Nuclear Information System (INIS)

Oakberg, J.A.

1976-12-01

Radioisotope scanning in the field of nuclear medicine provides a method for the mapping of a radioactive drug in the human body to produce maps (images) which prove useful in detecting abnormalities in vital organs. At best, radioisotope scanning methods produce images with poor counting statistics. One solution to improving the body scan images is using dedicated small computers with appropriate software to process the scan data. Eleven methods for processing image data are compared

MR imaging of congenital heart diseases in adolescents and adults

Energy Technology Data Exchange (ETDEWEB)

Choe, Yeon Hyeon; Kang, I Seok; Park, Seung Woo; Lee, Heung Jae [Sungkwunkwan University School of Medicine, Seoul (Korea, Republic of)

2001-09-01

Echocardiography and catheterization angiography suffer certain limitations in the evaluation of congenital heart diseases in adults, though these are overcome by MRI, in which a wide field-of view, unlimited multiplanar imaging capability and three-dimensional contrast-enhanced MR angiography techniques are used. In adults, recently introduced fast imaging techniques provide cardiac MR images of sufficient quality and with less artifacts. Ventricular volume, ejection fraction, and vascular flow measurements, including pressure gradients and pulmonary-to-systemic flow ratio, can be calculated or obtained using fast cine MRI, phase-contrast MR flow-velocity mapping, and semiautomatic analysis software. MRI is superior to echocardiography in diagnosing partial anomalous pulmonary venous connection, unroofed coronary sinus, anomalies of the pulmonary arteries, aorta and systemic veins, complex heart diseases, and postsurgical sequelae. Biventricular function is reliably evaluated with cine MRI after repair of tetralogy of Fallot, and Senning's and Mustard's operations. MRI has an important and growing role in the morphologic and functional assessment of congenital heart diseases in adolescents and adults.

Diagnosis of dorsal inter osseous pseudotumours by magnetic resonance imaging

International Nuclear Information System (INIS)

Peh, W.C.G.; Wong, L.L.S.; Ip, W.Y.

1999-01-01

Two middle-aged-patients each presenting with a progressively enlarging mass in the first dorsal web space of their hands are reported. Magnetic resonance imaging (MRI) demonstrated the cause to be a hypertrophic first dorsal inter osseous muscle, with normal T1, T2 and post-gadopentetate dimeglumine signal characteristics. The ability of MRI to diagnose anatomical variants of hand muscles is important in the clinical management of patients with these pseudotumours. The usefulness of magnetic resonance imaging (MRI) in evaluation of soft tissue tumours of the musculoskeletal system is now widely accepted. Its ability to maximize contrast between tumour and adjacent normal tissue in a multiplanar manner makes it the imaging modality of choice in pre-operative staging of soft tissue masses. In the hand and wrist, where benign tumours predominate, MRI may provide a specific diagnosis. We describe two cases in which MRI demonstrated the cause of a hand pseudotumour to be due to hypertrophy of the first dorsal inter osseous muscle. Copyright (1999) Blackwell Science Pty Ltd

Diagnosis of dorsal inter osseous pseudotumours by magnetic resonance imaging

Energy Technology Data Exchange (ETDEWEB)

Peh, W.C.G.; Wong, L.L.S. [The University of Hong Kong, Queen Mary Hospital, (Hong Kong). Hand Surgery Division, Department of Diagnotic Radiology; Ip, W.Y. [The University of Hong Kong, Queen Mary Hospital, (Hong Kong). Hand Surgery Division, Department of Orthopaedic Surgery

1999-08-01

Two middle-aged-patients each presenting with a progressively enlarging mass in the first dorsal web space of their hands are reported. Magnetic resonance imaging (MRI) demonstrated the cause to be a hypertrophic first dorsal inter osseous muscle, with normal T1, T2 and post-gadopentetate dimeglumine signal characteristics. The ability of MRI to diagnose anatomical variants of hand muscles is important in the clinical management of patients with these pseudotumours. The usefulness of magnetic resonance imaging (MRI) in evaluation of soft tissue tumours of the musculoskeletal system is now widely accepted. Its ability to maximize contrast between tumour and adjacent normal tissue in a multiplanar manner makes it the imaging modality of choice in pre-operative staging of soft tissue masses. In the hand and wrist, where benign tumours predominate, MRI may provide a specific diagnosis. We describe two cases in which MRI demonstrated the cause of a hand pseudotumour to be due to hypertrophy of the first dorsal inter osseous muscle. Copyright (1999) Blackwell Science Pty Ltd 20 refs., 3 figs.

Speckle imaging using the principle value decomposition method

International Nuclear Information System (INIS)

Sherman, J.W.

1978-01-01

Obtaining diffraction-limited images in the presence of atmospheric turbulence is a topic of current interest. Two types of approaches have evolved: real-time correction and speckle imaging. A speckle imaging reconstruction method was developed by use of an ''optimal'' filtering approach. This method is based on a nonlinear integral equation which is solved by principle value decomposition. The method was implemented on a CDC 7600 for study. The restoration algorithm is discussed and its performance is illustrated. 7 figures

Missed rib fractures on evaluation of initial chest CT for trauma patients: pattern analysis and diagnostic value of coronal multiplanar reconstruction images with multidetector row CT.

Science.gov (United States)

Cho, S H; Sung, Y M; Kim, M S

2012-10-01

The objective of this study was to review the prevalence and radiological features of rib fractures missed on initial chest CT evaluation, and to examine the diagnostic value of additional coronal images in a large series of trauma patients. 130 patients who presented to an emergency room for blunt chest trauma underwent multidetector row CT of the thorax within the first hour during their stay, and had follow-up CT or bone scans as diagnostic gold standards. Images were evaluated on two separate occasions: once with axial images and once with both axial and coronal images. The detection rates of missed rib fractures were compared between readings using a non-parametric method of clustered data. In the cases of missed rib fractures, the shapes, locations and associated fractures were evaluated. 58 rib fractures were missed with axial images only and 52 were missed with both axial and coronal images (p=0.088). The most common shape of missed rib fractures was buckled (56.9%), and the anterior arc (55.2%) was most commonly involved. 21 (36.2%) missed rib fractures had combined fractures on the same ribs, and 38 (65.5%) were accompanied by fracture on neighbouring ribs. Missed rib fractures are not uncommon, and radiologists should be familiar with buckle fractures, which are frequently missed. Additional coronal imagescan be helpful in the diagnosis of rib fractures that are not seen on axial images.

Quality assessment in radiological imaging methods

International Nuclear Information System (INIS)

Herstel, W.

1985-01-01

The equipment used in diagnostic radiology is becoming more and more complicated. In the imaging process four components are distinguished, each of which can introduce loss in essential information: the X-ray source, the human body, the imaging system and the observer. In nearly all imaging methods the X-ray quantum fluctuations are a limitation to observation. But there are also technical factors. As an illustration it is shown how in a television scanning process the resolution is restricted by the system parameters. A short review is given of test devices and the results are given of an image comparison based on regular bar patterns. Although this method has the disadvantage of measuring mainly the limiting resolution, the results of the test correlate reasonably well with the subjective appreciations of radiographs of bony structures made by a group of trained radiologists. Fluoroscopic systems should preferably be tested using moving structures under dynamic conditions. (author)

Method for position emission mammography image reconstruction

Science.gov (United States)

Smith, Mark Frederick

2004-10-12

An image reconstruction method comprising accepting coincidence datat from either a data file or in real time from a pair of detector heads, culling event data that is outside a desired energy range, optionally saving the desired data for each detector position or for each pair of detector pixels on the two detector heads, and then reconstructing the image either by backprojection image reconstruction or by iterative image reconstruction. In the backprojection image reconstruction mode, rays are traced between centers of lines of response (LOR's), counts are then either allocated by nearest pixel interpolation or allocated by an overlap method and then corrected for geometric effects and attenuation and the data file updated. If the iterative image reconstruction option is selected, one implementation is to compute a grid Siddon retracing, and to perform maximum likelihood expectation maiximization (MLEM) computed by either: a) tracing parallel rays between subpixels on opposite detector heads; or b) tracing rays between randomized endpoint locations on opposite detector heads.

Circular SAR Optimization Imaging Method of Buildings

Directory of Open Access Journals (Sweden)

Wang Jian-feng

2015-12-01

Full Text Available The Circular Synthetic Aperture Radar (CSAR can obtain the entire scattering properties of targets because of its great ability of 360° observation. In this study, an optimal orientation of the CSAR imaging algorithm of buildings is proposed by applying a combination of coherent and incoherent processing techniques. FEKO software is used to construct the electromagnetic scattering modes and simulate the radar echo. The FEKO imaging results are compared with the isotropic scattering results. On comparison, the optimal azimuth coherent accumulation angle of CSAR imaging of buildings is obtained. Practically, the scattering directions of buildings are unknown; therefore, we divide the 360° echo of CSAR into many overlapped and few angle echoes corresponding to the sub-aperture and then perform an imaging procedure on each sub-aperture. Sub-aperture imaging results are applied to obtain the all-around image using incoherent fusion techniques. The polarimetry decomposition method is used to decompose the all-around image and further retrieve the edge information of buildings successfully. The proposed method is validated with P-band airborne CSAR data from Sichuan, China.

Research of x-ray automatic image mosaic method

Science.gov (United States)

Liu, Bin; Chen, Shunan; Guo, Lianpeng; Xu, Wanpeng

2013-10-01

Image mosaic has widely applications value in the fields of medical image analysis, and it is a technology that carries on the spatial matching to a series of image which are overlapped with each other, and finally builds a seamless and high quality image which has high resolution and big eyeshot. In this paper, the method of grayscale cutting pseudo-color enhancement was firstly used to complete the mapping transformation from gray to the pseudo-color, and to extract SIFT features from the images. And then by making use of a similar measure of NCC (normalized cross correlation - Normalized cross-correlation), the method of RANSAC (Random Sample Consensus) was used to exclude the pseudofeature points right in order to complete the exact match of feature points. Finally, seamless mosaic and color fusion were completed by using wavelet multi-decomposition. The experiment shows that the method we used can effectively improve the precision and automation of the medical image mosaic, and provide an effective technical approach for automatic medical image mosaic.

Reconstruction CT imaging of the hypopharynx and the larynx

International Nuclear Information System (INIS)

Okuno, Tetsuji; Fujimura, Akiko; Murakami, Yasushi; Shiga, Hayao

1986-01-01

The multiplanar reconstruction CT imaging of the hypopharynx and the larynx was performed on a total of 20 cases: 8 with laryngeal carcinomas, 6 with hypopharyngeal carcinomas, 4 with vocal cord paralyses due to various causes, 1 with laryngeal amyloidosis, 1 with inflammatory granuloma of the hypopharynx. Coronal, segittal, and parasagittal reconstruction images were obtained from either 1 or 2 mm overlapping axial scans with 4 or 5 mm slice thickness (3 cases) using 5 sec scan times during queit breathing. In 15 cases with coronal reconstruction imaging, the anatomical derangements of the laryngopharyngeal structures especially along the undersurface of the true vocal cord to the false cord level, the lateral wall of the pyriform sinus, and the paraglottic space were demonstrated more clearly than the axial CT imaging. In 5 cases with sagittal reconstruction imaging, the vertical extension of the lesions through the anterior commisure was more clearly depicted than the axial CT imaging. In 8 cases with parasagittal reconstruction imaging, which is along the vocal fold or across the aryepiglottic fold, pathological changes along the aryepiglottic fold, the arytenoid-corniculate cartilage complex, and the tip of the pyriform sinus were more clearly demonstrated than the axial CT imaging. In determining the feasibility of conservation surgery of the larynx and the hypopharynx, reconstruction CT imaging is recommended as the diagnostic procedure of a choice, which would supplement the findings of the routine axial CT imaging. (author)

IMPROVING THE QUALITY OF NEAR-INFRARED IMAGING OF IN VIVOBLOOD VESSELS USING IMAGE FUSION METHODS

DEFF Research Database (Denmark)

Jensen, Andreas Kryger; Savarimuthu, Thiusius Rajeeth; Sørensen, Anders Stengaard

2009-01-01

We investigate methods for improving the visual quality of in vivo images of blood vessels in the human forearm. Using a near-infrared light source and a dual CCD chip camera system capable of capturing images at visual and nearinfrared spectra, we evaluate three fusion methods in terms...... of their capability of enhancing the blood vessels while preserving the spectral signature of the original color image. Furthermore, we investigate a possibility of removing hair in the images using a fusion rule based on the "a trous" stationary wavelet decomposition. The method with the best overall performance...... with both speed and quality in mind is the Intensity Injection method. Using the developed system and the methods presented in this article, it is possible to create images of high visual quality with highly emphasized blood vessels....

Influence of image reconstruction methods on statistical parametric mapping of brain PET images

International Nuclear Information System (INIS)

Yin Dayi; Chen Yingmao; Yao Shulin; Shao Mingzhe; Yin Ling; Tian Jiahe; Cui Hongyan

2007-01-01

Objective: Statistic parametric mapping (SPM) was widely recognized as an useful tool in brain function study. The aim of this study was to investigate if imaging reconstruction algorithm of PET images could influence SPM of brain. Methods: PET imaging of whole brain was performed in six normal volunteers. Each volunteer had two scans with true and false acupuncturing. The PET scans were reconstructed using ordered subsets expectation maximization (OSEM) and filtered back projection (FBP) with 3 varied parameters respectively. The images were realigned, normalized and smoothed using SPM program. The difference between true and false acupuncture scans was tested using a matched pair t test at every voxel. Results: (1) SPM corrected multiple comparison (P corrected uncorrected <0.001): SPM derived from the images with different reconstruction method were different. The largest difference, in number and position of the activated voxels, was noticed between FBP and OSEM re- construction algorithm. Conclusions: The method of PET image reconstruction could influence the results of SPM uncorrected multiple comparison. Attention should be paid when the conclusion was drawn using SPM uncorrected multiple comparison. (authors)

Three-dimensional image signals: processing methods

Science.gov (United States)

Schiopu, Paul; Manea, Adrian; Craciun, Anca-Ileana; Craciun, Alexandru

2010-11-01

Over the years extensive studies have been carried out to apply coherent optics methods in real-time processing, communications and transmission image. This is especially true when a large amount of information needs to be processed, e.g., in high-resolution imaging. The recent progress in data-processing networks and communication systems has considerably increased the capacity of information exchange. We describe the results of literature investigation research of processing methods for the signals of the three-dimensional images. All commercially available 3D technologies today are based on stereoscopic viewing. 3D technology was once the exclusive domain of skilled computer-graphics developers with high-end machines and software. The images capture from the advanced 3D digital camera can be displayed onto screen of the 3D digital viewer with/ without special glasses. For this is needed considerable processing power and memory to create and render the complex mix of colors, textures, and virtual lighting and perspective necessary to make figures appear three-dimensional. Also, using a standard digital camera and a technique called phase-shift interferometry we can capture "digital holograms." These are holograms that can be stored on computer and transmitted over conventional networks. We present some research methods to process "digital holograms" for the Internet transmission and results.

An Improved Image Contrast Assessment Method

Directory of Open Access Journals (Sweden)

Yuanyuan Fan

2013-07-01

Full Text Available Contrast is an important factor affecting the image quality. In order to overcome the problems of local band-limited contrast, a novel image contrast assessment method based on the property of HVS is proposed. Firstly, the image by low-pass filter is performed fast wavelet decomposition. Secondly, all levels of band-pass filtered image and its corresponding low-pass filtered image are obtained by processing wavelet coefficients. Thirdly, local band-limited contrast is calculated, and the local band-limited contrast entropy is calculated according to the definition of entropy, Finally, the contrast entropy of image is obtained by averaging the local band-limited contrast entropy weighed using CSF coefficient. The experiment results show that the best contrast image can be accurately identified in the sequence images obtained by adjusting the exposure time and stretching gray respectively, the assessment results accord with human visual characteristics and make up the lack of local band-limited contrast.

New Finger Biometric Method Using Near Infrared Imaging

Science.gov (United States)

Lee, Eui Chul; Jung, Hyunwoo; Kim, Daeyeoul

2011-01-01

In this paper, we propose a new finger biometric method. Infrared finger images are first captured, and then feature extraction is performed using a modified Gaussian high-pass filter through binarization, local binary pattern (LBP), and local derivative pattern (LDP) methods. Infrared finger images include the multimodal features of finger veins and finger geometries. Instead of extracting each feature using different methods, the modified Gaussian high-pass filter is fully convolved. Therefore, the extracted binary patterns of finger images include the multimodal features of veins and finger geometries. Experimental results show that the proposed method has an error rate of 0.13%. PMID:22163741

Image Processing Methods Usable for Object Detection on the Chessboard

Directory of Open Access Journals (Sweden)

Beran Ladislav

2016-01-01

Full Text Available Image segmentation and object detection is challenging problem in many research. Although many algorithms for image segmentation have been invented, there is no simple algorithm for image segmentation and object detection. Our research is based on combination of several methods for object detection. The first method suitable for image segmentation and object detection is colour detection. This method is very simply, but there is problem with different colours. For this method it is necessary to have precisely determined colour of segmented object before all calculations. In many cases it is necessary to determine this colour manually. Alternative simply method is method based on background removal. This method is based on difference between reference image and detected image. In this paper several methods suitable for object detection are described. Thisresearch is focused on coloured object detection on chessboard. The results from this research with fusion of neural networks for user-computer game checkers will be applied.

MR imaging of peripheral nervous system involvement: Parsonage-Turner syndrome.

Science.gov (United States)

Zara, Gabriella; Gasparotti, Roberto; Manara, Renzo

2012-04-15

A 55-year-old woman complained of right scapular pain, like burning, radiating down his right arm and numbness in the first three fingers of the hand. Neurologic examination showed a slight deficit of the right brachial triceps muscle. Neurophysiological assessment showed a mild involvement of the seventh right spinal root (C7). Conventional MR imaging of the cervical spine showed mild disc protrusion at level C5-C6 without spinal root compression. High resolution MR neurography with multiplanar reconstruction along the course of the right brachial plexus showed a mild increase in signal intensity and thickening of the C7 root, middle trunk and posterior cord, consistent with Parsonage-Turner Syndrome. STIR images showed increased signal intensity in the right infraspinatus muscle innervated by the suprascapular nerve. In our case, sensitivity and specificity of the new MR sequences are higher than the clinical and neurophysiological evaluations. Copyright © 2011 Elsevier B.V. All rights reserved.

Keyhole imaging method for dynamic objects behind the occlusion area

Science.gov (United States)

Hao, Conghui; Chen, Xi; Dong, Liquan; Zhao, Yuejin; Liu, Ming; Kong, Lingqin; Hui, Mei; Liu, Xiaohua; Wu, Hong

2018-01-01

A method of keyhole imaging based on camera array is realized to obtain the video image behind a keyhole in shielded space at a relatively long distance. We get the multi-angle video images by using a 2×2 CCD camera array to take the images behind the keyhole in four directions. The multi-angle video images are saved in the form of frame sequences. This paper presents a method of video frame alignment. In order to remove the non-target area outside the aperture, we use the canny operator and morphological method to realize the edge detection of images and fill the images. The image stitching of four images is accomplished on the basis of the image stitching algorithm of two images. In the image stitching algorithm of two images, the SIFT method is adopted to accomplish the initial matching of images, and then the RANSAC algorithm is applied to eliminate the wrong matching points and to obtain a homography matrix. A method of optimizing transformation matrix is proposed in this paper. Finally, the video image with larger field of view behind the keyhole can be synthesized with image frame sequence in which every single frame is stitched. The results show that the screen of the video is clear and natural, the brightness transition is smooth. There is no obvious artificial stitching marks in the video, and it can be applied in different engineering environment .

Research of ART method in CT image reconstruction

International Nuclear Information System (INIS)

Li Zhipeng; Cong Peng; Wu Haifeng

2005-01-01

This paper studied Algebraic Reconstruction Technique (ART) in CT image reconstruction. Discussed the ray number influence on image quality. And the adopting of smooth method got high quality CT image. (authors)

Hiding a Covert Digital Image by Assembling the RSA Encryption Method and the Binary Encoding Method

Directory of Open Access Journals (Sweden)

Kuang Tsan Lin

2014-01-01

Full Text Available The Rivest-Shamir-Adleman (RSA encryption method and the binary encoding method are assembled to form a hybrid hiding method to hide a covert digital image into a dot-matrix holographic image. First, the RSA encryption method is used to transform the covert image to form a RSA encryption data string. Then, all the elements of the RSA encryption data string are transferred into binary data. Finally, the binary data are encoded into the dot-matrix holographic image. The pixels of the dot-matrix holographic image contain seven groups of codes used for reconstructing the covert image. The seven groups of codes are identification codes, covert-image dimension codes, covert-image graylevel codes, pre-RSA bit number codes, RSA key codes, post-RSA bit number codes, and information codes. The reconstructed covert image derived from the dot-matrix holographic image and the original covert image are exactly the same.

Analysis of live cell images: Methods, tools and opportunities.

Science.gov (United States)

Nketia, Thomas A; Sailem, Heba; Rohde, Gustavo; Machiraju, Raghu; Rittscher, Jens

2017-02-15

Advances in optical microscopy, biosensors and cell culturing technologies have transformed live cell imaging. Thanks to these advances live cell imaging plays an increasingly important role in basic biology research as well as at all stages of drug development. Image analysis methods are needed to extract quantitative information from these vast and complex data sets. The aim of this review is to provide an overview of available image analysis methods for live cell imaging, in particular required preprocessing image segmentation, cell tracking and data visualisation methods. The potential opportunities recent advances in machine learning, especially deep learning, and computer vision provide are being discussed. This review includes overview of the different available software packages and toolkits. Copyright © 2017. Published by Elsevier Inc.

An efficient direct method for image registration of flat objects

Science.gov (United States)

Nikolaev, Dmitry; Tihonkih, Dmitrii; Makovetskii, Artyom; Voronin, Sergei

2017-09-01

Image alignment of rigid surfaces is a rapidly developing area of research and has many practical applications. Alignment methods can be roughly divided into two types: feature-based methods and direct methods. Known SURF and SIFT algorithms are examples of the feature-based methods. Direct methods refer to those that exploit the pixel intensities without resorting to image features and image-based deformations are general direct method to align images of deformable objects in 3D space. Nevertheless, it is not good for the registration of images of 3D rigid objects since the underlying structure cannot be directly evaluated. In the article, we propose a model that is suitable for image alignment of rigid flat objects under various illumination models. The brightness consistency assumptions used for reconstruction of optimal geometrical transformation. Computer simulation results are provided to illustrate the performance of the proposed algorithm for computing of an accordance between pixels of two images.

Matrix Krylov subspace methods for image restoration

Directory of Open Access Journals (Sweden)

khalide jbilou

2015-09-01

Full Text Available In the present paper, we consider some matrix Krylov subspace methods for solving ill-posed linear matrix equations and in those problems coming from the restoration of blurred and noisy images. Applying the well known Tikhonov regularization procedure leads to a Sylvester matrix equation depending the Tikhonov regularized parameter. We apply the matrix versions of the well known Krylov subspace methods, namely the Least Squared (LSQR and the conjugate gradient (CG methods to get approximate solutions representing the restored images. Some numerical tests are presented to show the effectiveness of the proposed methods.

Quantitative imaging methods in osteoporosis.

Science.gov (United States)

Oei, Ling; Koromani, Fjorda; Rivadeneira, Fernando; Zillikens, M Carola; Oei, Edwin H G

2016-12-01

Osteoporosis is characterized by a decreased bone mass and quality resulting in an increased fracture risk. Quantitative imaging methods are critical in the diagnosis and follow-up of treatment effects in osteoporosis. Prior radiographic vertebral fractures and bone mineral density (BMD) as a quantitative parameter derived from dual-energy X-ray absorptiometry (DXA) are among the strongest known predictors of future osteoporotic fractures. Therefore, current clinical decision making relies heavily on accurate assessment of these imaging features. Further, novel quantitative techniques are being developed to appraise additional characteristics of osteoporosis including three-dimensional bone architecture with quantitative computed tomography (QCT). Dedicated high-resolution (HR) CT equipment is available to enhance image quality. At the other end of the spectrum, by utilizing post-processing techniques such as the trabecular bone score (TBS) information on three-dimensional architecture can be derived from DXA images. Further developments in magnetic resonance imaging (MRI) seem promising to not only capture bone micro-architecture but also characterize processes at the molecular level. This review provides an overview of various quantitative imaging techniques based on different radiological modalities utilized in clinical osteoporosis care and research.

Analysis of Non Local Image Denoising Methods

Science.gov (United States)

Pardo, Álvaro

Image denoising is probably one of the most studied problems in the image processing community. Recently a new paradigm on non local denoising was introduced. The Non Local Means method proposed by Buades, Morel and Coll attracted the attention of other researches who proposed improvements and modifications to their proposal. In this work we analyze those methods trying to understand their properties while connecting them to segmentation based on spectral graph properties. We also propose some improvements to automatically estimate the parameters used on these methods.

CT and MR imaging of primary tumors of the masticator space

International Nuclear Information System (INIS)

Aspestrand, F.; Boysen, M.

1992-01-01

A retrospective study of CT and MR examinations in 14 patients with benign and malignant tumors originating in the masticator space is presented. At presentation, 12 patients revealed tumor extension to adjacent regions and spaces. Perineutral tumor spread along trigeminal nerve branches to the cavernous sinus and orbits was combined with facial pain, and/or numbness, ophthalmoplegia, and exophthalmus. Detailed analysis of tumor growth and spread, enhancement and signal features at CT and MR imaging indicated that tumor histology was, with a few exceptions, nonspecific. More extensive growth and bone destruction was noted only among malignant tumors. MR imaging was found superior to CT in delineating tumor extension due to better soft tissue contrast resolution and multiplanar imaging. Posttreatment examinations were available in 11 patients and showed long-standing regional edema of the adjacent temporal lobe and masticator muscles in 4 out of 5 patients without clinical evidence of tumor. In 6 patients, CT and MR features were found almost unchanged with only small size differences after various forms of treatment. (orig.)

Usefulness of dual echo volumetric isotropic turbo spin echo acquisition (VISTA) in MR imaging of the temporomandibular joint

International Nuclear Information System (INIS)

Sugimori, Yuko; Tanaka, Shigeko; Naito, Yukari; Nishimura, Tetsuya; Yamamoto, Akira; Miki, Yukio; Ohfuji, Satoko; Katsumata, Yasutomo

2013-01-01

We investigated the ability to detect the articular disk and joint effusion of the temporomandibular joint (TMJ) of a method of dual echo volumetric isotropic turbo spin echo acquisition (DE-VISTA) additional fusion images (AFI). DE-VISTA was performed in the 26 TMJ of 13 volunteers and 26 TMJ of 13 patients. Two-dimensional (2D) dual echo turbo spin echo was performed in the 26 TMJ of 13 volunteers. On a workstation, we added proton density-weighted images (PDWI) and T 2 weighted images (T 2 WI) of the DE-VISTA per voxel to reconstruct DE-VISTA-AFI. Two radiologists reviewed these images visually and quantitatively. Visual evaluation of the articular disk was equivalent between DE-VISTA-AFI and 2D-PDWI. The sliding thin-slab multiplanar reformation (MPR) method of DE-VISTA-AFI could detect all articular disks. The ratio of contrast (CR) of adipose tissue by the articular disk to that of the articular disk itself was significantly higher in DE-VISTA-AFI than DE-VISTA-PDWI (P 2 WI but in only 3 of those joints in 2D-T 2 WI. The CR of joint effusion to adipose tissue on DE-VISTA-AFI did not differ significantly from that on DE-VISTA-PDWI. However, using DE-VISTA-T 2 WI in addition to DE-VISTA-PDWI, we could visually identify joint effusion on DE-VISTA-AFI that could not be identified on DE-VISTA-PDWI alone. DE-VISTA-AFI can depict the articular disk and a small amount of joint effusion by the required plane of MPR using the sliding thin-slab MPR method. (author)

Sharpening methods for images captured through Bayer matrix

Science.gov (United States)

Kalevo, Ossi; Rantanen, Henry, Jr.

2003-05-01

Image resolution and sharpness are essential criteria for a human observer when estimating the image quality. Typically cheap small-sized, low-resolution CMOS-camera sensors do not provide sharp enough images, at least when comparing to high-end digital cameras. Sharpening function can be used to increase the subjective sharpness seen by the observer. In this paper, few methods to apply sharpening for images captured by CMOS imaging sensors through color filter array (CFA) are compared. The sharpening easily adds also the visibility of noise, pixel-cross talk and interpolation artifacts. Necessary arrangements to avoid the amplification of these unwanted phenomenon are discussed. By applying the sharpening only to the green component the processing power requirements can be clearly reduced. By adjusting the red and blue component sharpness, according to the green component sharpening, creation of false colors are reduced highly. Direction search sharpening method can be used to reduce the amplification of the artifacts caused by the CFA interpolation (CFAI). The comparison of the presented methods is based mainly on subjective image quality. Also the processing power and memory requirements are considered.

MRI in head trauma

International Nuclear Information System (INIS)

Hong, Jin Kyo

1986-01-01

In the diagnosis of head injury, Magnetic Resonance Imaging (MRI), like CT, is an effective method of distinguishing between intracerebral and extracerebral lesions. In our experience of MRI, early hematomas are almost isointense by Saturation Recovery (SR) method, so these must be performed with Spin Echo (SE) method for better visualization of hematomas. Isodense subdural hematomas, which is a diagnostic dilemma on CT images, are clearly seen on MRI. Delayed hematomas or residual parenchymal lesions are better demonstrated on MRI than on CT. Direct cornal, sagittal images and multiplanar facility of MRI provides excellent visualization of the the location and shape of extracerebral collection of hematoma. For the screening of head traumas, SE method is a technique of choice because of its excellent sensitivity within limited time.

MRI in head trauma

Energy Technology Data Exchange (ETDEWEB)

Hong, Jin Kyo [Shin Wha Hospital, Seoul (Korea, Republic of)

1986-02-15

In the diagnosis of head injury, Magnetic Resonance Imaging (MRI), like CT, is an effective method of distinguishing between intracerebral and extracerebral lesions. In our experience of MRI, early hematomas are almost isointense by Saturation Recovery (SR) method, so these must be performed with Spin Echo (SE) method for better visualization of hematomas. Isodense subdural hematomas, which is a diagnostic dilemma on CT images, are clearly seen on MRI. Delayed hematomas or residual parenchymal lesions are better demonstrated on MRI than on CT. Direct cornal, sagittal images and multiplanar facility of MRI provides excellent visualization of the the location and shape of extracerebral collection of hematoma. For the screening of head traumas, SE method is a technique of choice because of its excellent sensitivity within limited time.

Multi-crack imaging using nonclassical nonlinear acoustic method

Science.gov (United States)

Zhang, Lue; Zhang, Ying; Liu, Xiao-Zhou; Gong, Xiu-Fen

2014-10-01

Solid materials with cracks exhibit the nonclassical nonlinear acoustical behavior. The micro-defects in solid materials can be detected by nonlinear elastic wave spectroscopy (NEWS) method with a time-reversal (TR) mirror. While defects lie in viscoelastic solid material with different distances from one another, the nonlinear and hysteretic stress—strain relation is established with Preisach—Mayergoyz (PM) model in crack zone. Pulse inversion (PI) and TR methods are used in numerical simulation and defect locations can be determined from images obtained by the maximum value. Since false-positive defects might appear and degrade the imaging when the defects are located quite closely, the maximum value imaging with a time window is introduced to analyze how defects affect each other and how the fake one occurs. Furthermore, NEWS-TR-NEWS method is put forward to improve NEWS-TR scheme, with another forward propagation (NEWS) added to the existing phases (NEWS and TR). In the added phase, scanner locations are determined by locations of all defects imaged in previous phases, so that whether an imaged defect is real can be deduced. NEWS-TR-NEWS method is proved to be effective to distinguish real defects from the false-positive ones. Moreover, it is also helpful to detect the crack that is weaker than others during imaging procedure.

Evaluation of Rib Fractures on a Single-in-plane Image Reformation of the Rib Cage in CT Examinations.

Science.gov (United States)

Dankerl, Peter; Seuss, Hannes; Ellmann, Stephan; Cavallaro, Alexander; Uder, Michael; Hammon, Matthias

2017-02-01

This study aimed to evaluate the diagnostic performance of using a reformatted single-in-plane image reformation of the rib cage for the detection of rib fractures in computed tomography (CT) examinations, employing different levels of radiological experience. We retrospectively evaluated 10 consecutive patients with and 10 patients without rib fractures, whose CT scans were reformatted to a single-in-plane image reformation of the rib cage. Eight readers (two radiologists, two residents in radiology, and four interns) independently evaluated the images for the presence of rib fractures using a reformatted single-in-plane image and a multi-planar image reformation. The time limit was 30 seconds for each read. A consensus of two radiologist readings was considered as the reference standard. Diagnostic performance (sensitivity, specificity, positive predictive value [PPV], and negative predictive value [NPV]) was assessed and evaluated per rib and per location (anterior, lateral, posterior). To determine the time limit, we prospectively analyzed the average time it took radiologists to assess the rib cage, in a bone window setting, in 50 routine CT examinations. McNemar test was used to compare the diagnostic performances. Single image reformation was successful in all 20 patients. The sensitivity, specificity, PPV, and NPV for the detection of rib fractures using the conventional multi-planar read were 77.5%, 99.2%, 89.9%, and 98.0% for radiologists; 46.3%, 99.7%, 92.5%, and 95.3% for residents; and 29.4%, 99.4%, 82.5%, and 93.9% for interns, respectively. Sensitivity, PPV, and NPV increased across all three groups of experience, using the reformatted single-in-plane image of the rib cage (radiologists: 85.0%, 98.6%, and 98.7%; residents: 80.0%, 92.8%, and 98.2%; interns: 66.9%, 89.9%, and 97.1%), whereas specificity did not change significantly (99.9%, 99.4%, and 99.3%). The diagnostic performance of the interns and residents was significantly better when

Research on interpolation methods in medical image processing.

Science.gov (United States)

Pan, Mei-Sen; Yang, Xiao-Li; Tang, Jing-Tian

2012-04-01

Image interpolation is widely used for the field of medical image processing. In this paper, interpolation methods are divided into three groups: filter interpolation, ordinary interpolation and general partial volume interpolation. Some commonly-used filter methods for image interpolation are pioneered, but the interpolation effects need to be further improved. When analyzing and discussing ordinary interpolation, many asymmetrical kernel interpolation methods are proposed. Compared with symmetrical kernel ones, the former are have some advantages. After analyzing the partial volume and generalized partial volume estimation interpolations, the new concept and constraint conditions of the general partial volume interpolation are defined, and several new partial volume interpolation functions are derived. By performing the experiments of image scaling, rotation and self-registration, the interpolation methods mentioned in this paper are compared in the entropy, peak signal-to-noise ratio, cross entropy, normalized cross-correlation coefficient and running time. Among the filter interpolation methods, the median and B-spline filter interpolations have a relatively better interpolating performance. Among the ordinary interpolation methods, on the whole, the symmetrical cubic kernel interpolations demonstrate a strong advantage, especially the symmetrical cubic B-spline interpolation. However, we have to mention that they are very time-consuming and have lower time efficiency. As for the general partial volume interpolation methods, from the total error of image self-registration, the symmetrical interpolations provide certain superiority; but considering the processing efficiency, the asymmetrical interpolations are better.

A fast and automatic mosaic method for high-resolution satellite images

Science.gov (United States)

Chen, Hongshun; He, Hui; Xiao, Hongyu; Huang, Jing

2015-12-01

We proposed a fast and fully automatic mosaic method for high-resolution satellite images. First, the overlapped rectangle is computed according to geographical locations of the reference and mosaic images and feature points on both the reference and mosaic images are extracted by a scale-invariant feature transform (SIFT) algorithm only from the overlapped region. Then, the RANSAC method is used to match feature points of both images. Finally, the two images are fused into a seamlessly panoramic image by the simple linear weighted fusion method or other method. The proposed method is implemented in C++ language based on OpenCV and GDAL, and tested by Worldview-2 multispectral images with a spatial resolution of 2 meters. Results show that the proposed method can detect feature points efficiently and mosaic images automatically.

Imaging the cranial nerves: Part I: Methodology, infectious and inflammatory, traumatic and congenital lesions

Energy Technology Data Exchange (ETDEWEB)

Borges, Alexandra [Instituto Portugues de Oncologia Francisco Gentil- Centro de Lisboa, Department of Radiology, Lisboa Codex (Portugal); Casselman, Jan [A.Z. St. Jan Brugge Hospital, Department of Radiology, Brugge (Belgium); A.Z. St. Augustinus Antwerpen Hospitals, Department of Radiology, Antwerpen (Belgium)

2007-08-15

Many disease processes manifest either primarily or secondarily by cranial nerve deficits. Neurologists, ENT surgeons, ophthalmologists and maxillo-facial surgeons are often confronted with patients with symptoms and signs of cranial nerve dysfunction. Seeking the cause of this dysfunction is a common indication for imaging. In recent decades we have witnessed an unprecedented improvement in imaging techniques, allowing direct visualization of increasingly small anatomic structures. The emergence of volumetric CT scanners, higher field MR scanners in clinical practice and higher resolution MR sequences has made a tremendous contribution to the development of cranial nerve imaging. The use of surface coils and parallel imaging allows sub-millimetric visualization of nerve branches and volumetric 3D imaging. Both with CT and MR, multiplanar and curved reconstructions can follow the entire course of a cranial nerve or branch, improving tremendously our diagnostic yield of neural pathology. This review article will focus on the contribution of current imaging techniques in the depiction of normal anatomy and on infectious and inflammatory, traumatic and congenital pathology affecting the cranial nerves. A detailed discussion of individual cranial nerves lesions is beyond the scope of this article. (orig.)

Imaging the cranial nerves: Part I: Methodology, infectious and inflammatory, traumatic and congenital lesions

International Nuclear Information System (INIS)

Borges, Alexandra; Casselman, Jan

2007-01-01

Many disease processes manifest either primarily or secondarily by cranial nerve deficits. Neurologists, ENT surgeons, ophthalmologists and maxillo-facial surgeons are often confronted with patients with symptoms and signs of cranial nerve dysfunction. Seeking the cause of this dysfunction is a common indication for imaging. In recent decades we have witnessed an unprecedented improvement in imaging techniques, allowing direct visualization of increasingly small anatomic structures. The emergence of volumetric CT scanners, higher field MR scanners in clinical practice and higher resolution MR sequences has made a tremendous contribution to the development of cranial nerve imaging. The use of surface coils and parallel imaging allows sub-millimetric visualization of nerve branches and volumetric 3D imaging. Both with CT and MR, multiplanar and curved reconstructions can follow the entire course of a cranial nerve or branch, improving tremendously our diagnostic yield of neural pathology. This review article will focus on the contribution of current imaging techniques in the depiction of normal anatomy and on infectious and inflammatory, traumatic and congenital pathology affecting the cranial nerves. A detailed discussion of individual cranial nerves lesions is beyond the scope of this article. (orig.)

Development of Quantification Method for Bioluminescence Imaging

International Nuclear Information System (INIS)

Kim, Hyeon Sik; Min, Jung Joon; Lee, Byeong Il; Choi, Eun Seo; Tak, Yoon O; Choi, Heung Kook; Lee, Ju Young

2009-01-01

Optical molecular luminescence imaging is widely used for detection and imaging of bio-photons emitted by luminescent luciferase activation. The measured photons in this method provide the degree of molecular alteration or cell numbers with the advantage of high signal-to-noise ratio. To extract useful information from the measured results, the analysis based on a proper quantification method is necessary. In this research, we propose a quantification method presenting linear response of measured light signal to measurement time. We detected the luminescence signal by using lab-made optical imaging equipment of animal light imaging system (ALIS) and different two kinds of light sources. One is three bacterial light-emitting sources containing different number of bacteria. The other is three different non-bacterial light sources emitting very weak light. By using the concept of the candela and the flux, we could derive simplified linear quantification formula. After experimentally measuring light intensity, the data was processed with the proposed quantification function. We could obtain linear response of photon counts to measurement time by applying the pre-determined quantification function. The ratio of the re-calculated photon counts and measurement time present a constant value although different light source was applied. The quantification function for linear response could be applicable to the standard quantification process. The proposed method could be used for the exact quantitative analysis in various light imaging equipment with presenting linear response behavior of constant light emitting sources to measurement time

Oral cavity squamous cell carcinoma: Role of pretreatment imaging and its influence on management

International Nuclear Information System (INIS)

Arya, S.; Rane, P.; Deshmukh, A.

2014-01-01

Squamous cell carcinoma (SCC) is the commonest malignancy in the oral cavity. The oral cavity has several subsites. Knowledge of the patterns of disease spread at each subsite with the impact on treatment and prognosis provides a deeper understanding of the role of imaging. Information from imaging helps accurate staging, assess resectability, and plan multimodality treatment. Mandibular erosion, posterior soft tissue extent, and perineural spread influence treatment and prognosis in gingival, buccal, and retromolar trigone (RMT) cancers. Multidetector computed tomography (MDCT) with multiplanar reformations and bone and soft tissue algorithms provides the highest specificity for bone erosion. Hard palate SCC is optimally imaged with contrast-enhanced magnetic resonance imaging (MRI) to detect perineural spread. In oral tongue and floor of the mouth (FOM) SCC, extrinsic muscle invasion, extension across the midline, extent of posterior and inferior spread, and proximity to the hyoid are issues that impact therapeutic options. Contrast-enhanced MRI is the optimal imaging method for staging the primary due to its superior soft tissue resolution. In oral tongue SCCs with tumour thickness ≤4 mm, elective neck dissection can be avoided. For nodal staging (N-staging), all imaging methods are comparable, but fall short of surgical staging. Sentinel lymph node biopsy has a promising role in N-staging. Positron emission tomography (PET)/integrated PET/CT has no role in evaluating the clinically negative neck. PET/CT has a role in pretreatment evaluation of advanced oral cavity SCC for depicting distant metastases and for mapping nodal extent in the clinically positive neck. Diffusion-weighted MRI, dynamic contrast-enhanced MRI, and CT perfusion have a potential role as baseline pretreatment studies for response assessment to chemoradiation in advanced oral cavity SCC. - Highlights: • Brief outline of treatment principles in oral cavity squamous cell carcinoma (OCSCC

MR imaging of brachial plexus

International Nuclear Information System (INIS)

Carriero, A.; Ciccotosto, C.; Dragani, M.; Manes, L.; Bonomo, L.

1991-01-01

The brachial plexus is a difficult region to evaluate with radiological techniques. MR imaging has great potentials for the depiction of the various anatomical structures of the branchial plexus - i.e., spinal ganglion, ventral nerve rami root exit of the neural foramina, trunks an cordes. Moreover, MR imaging, thanks to its direct multiplanarity, to its excellent soft-tissue contrast, and to its lack of motion artifacts, allows good evaluation of pathologic conditions in the branchial plexus, especially traumas and cancers. On the contrary CT, in spite of its high spatial resolution and good contrast, cannot demonstrate the anatomical structures of the brachial plexus. US detects superficials structures, and conventional radiographs depict only indirect changes in the adjacent lung apex and skeletal structures. From November 1989 to May 1990, 20 normal volunteers (15 males and 5 females; average age: 35 years) were studied with MR imaging. Multisection technique was employed with a dedicated coil and a primary coil. The anatomical structures of the brachial plexus were clearly demonstrated by T1-weighted sequences on the sagittal and axial planes. T2-weighted pulse sequences on the coronal plane were useful for the anatomical definition of the brachial plexus and for eventual tissue characterization. The correct representation of the anatomical structures of the brachial plexus allowed by MR imaging with author's standard technique makes MR imaging the most appropriate exam for the diagnosis of pathologic conditions in the brachial plexus, although its use must be suggested by specific clinical questions

Blind image deconvolution methods and convergence

CERN Document Server

Chaudhuri, Subhasis; Rameshan, Renu

2014-01-01

Blind deconvolution is a classical image processing problem which has been investigated by a large number of researchers over the last four decades. The purpose of this monograph is not to propose yet another method for blind image restoration. Rather the basic issue of deconvolvability has been explored from a theoretical view point. Some authors claim very good results while quite a few claim that blind restoration does not work. The authors clearly detail when such methods are expected to work and when they will not. In order to avoid the assumptions needed for convergence analysis in the

Imaging of laryngeal trauma

Energy Technology Data Exchange (ETDEWEB)

Becker, Minerva, E-mail: Minerva.Becker@hcuge.ch [Department of Radiology, Geneva University Hospital, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14 (Switzerland); Leuchter, Igor, E-mail: Igor.Leuchter@hcuge.ch [Department of Otorhinolaryngology and Cervico-facial Surgery, University Hospital of Geneva, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14 (Switzerland); Platon, Alexandra, E-mail: Alexandra.Platon@hcuge.ch [Department of Radiology, Geneva University Hospital, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14 (Switzerland); Becker, Christoph D., E-mail: Christoph.Becker@hcuge.ch [Department of Radiology, Geneva University Hospital, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14 (Switzerland); Dulguerov, Pavel, E-mail: Pavel.Dulguerov@hcuge.ch [Department of Otorhinolaryngology and Cervico-facial Surgery, University Hospital of Geneva, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14 (Switzerland); Varoquaux, Arthur, E-mail: Arthur.Varoquaux@hcuge.ch [Department of Radiology, Geneva University Hospital, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14 (Switzerland)

2014-01-15

External laryngeal trauma is a rare but potentially life-threatening situation in the acutely injured patient. Trauma mechanism and magnitude, maximum focus of the applied force, and patient related factors, such as age and ossification of the laryngeal cartilages influence the spectrum of observed injuries. Their correct diagnosis and prompt management are paramount in order to avoid patient death or long-term impairment of breathing, swallowing and speaking. The current review provides a comprehensive approach to the radiologic interpretation of imaging studies performed in patients with suspected laryngeal injury. It describes the key anatomic structures that are relevant in laryngeal trauma and discusses the clinical role of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the acute emergency situation. The added value of two-dimensional multiplanar reconstructions (2D MPR), three-dimensional volume rendering (3D VR) and virtual endoscopy (VE) for the non-invasive evaluation of laryngeal injuries and for treatment planning is discussed. The clinical presentation, biomechanics of injury, diagnostic pitfalls and pearls, common and uncommon findings are reviewed with emphasis of fracture patterns, involvement of laryngeal joints, intra- and extralaryngeal soft tissue injuries, and complications seen in the acute emergency situation. The radiologic appearance of common and less common long-term sequelae, as well as treatment options are equally addressed.

Imaging of laryngeal trauma

International Nuclear Information System (INIS)

Becker, Minerva; Leuchter, Igor; Platon, Alexandra; Becker, Christoph D.; Dulguerov, Pavel; Varoquaux, Arthur

2014-01-01

External laryngeal trauma is a rare but potentially life-threatening situation in the acutely injured patient. Trauma mechanism and magnitude, maximum focus of the applied force, and patient related factors, such as age and ossification of the laryngeal cartilages influence the spectrum of observed injuries. Their correct diagnosis and prompt management are paramount in order to avoid patient death or long-term impairment of breathing, swallowing and speaking. The current review provides a comprehensive approach to the radiologic interpretation of imaging studies performed in patients with suspected laryngeal injury. It describes the key anatomic structures that are relevant in laryngeal trauma and discusses the clinical role of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the acute emergency situation. The added value of two-dimensional multiplanar reconstructions (2D MPR), three-dimensional volume rendering (3D VR) and virtual endoscopy (VE) for the non-invasive evaluation of laryngeal injuries and for treatment planning is discussed. The clinical presentation, biomechanics of injury, diagnostic pitfalls and pearls, common and uncommon findings are reviewed with emphasis of fracture patterns, involvement of laryngeal joints, intra- and extralaryngeal soft tissue injuries, and complications seen in the acute emergency situation. The radiologic appearance of common and less common long-term sequelae, as well as treatment options are equally addressed

Integration of image exposure time into a modified laser speckle imaging method

Energy Technology Data Exchange (ETDEWEB)

RamIrez-San-Juan, J C; Salazar-Hermenegildo, N; Ramos-Garcia, R; Munoz-Lopez, J [Optics Department, INAOE, Puebla (Mexico); Huang, Y C [Department of Electrical Engineering and Computer Science, University of California, Irvine, CA (United States); Choi, B, E-mail: jcram@inaoep.m [Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA (United States)

2010-11-21

Speckle-based methods have been developed to characterize tissue blood flow and perfusion. One such method, called modified laser speckle imaging (mLSI), enables computation of blood flow maps with relatively high spatial resolution. Although it is known that the sensitivity and noise in LSI measurements depend on image exposure time, a fundamental disadvantage of mLSI is that it does not take into account this parameter. In this work, we integrate the exposure time into the mLSI method and provide experimental support of our approach with measurements from an in vitro flow phantom.

Integration of image exposure time into a modified laser speckle imaging method

International Nuclear Information System (INIS)

RamIrez-San-Juan, J C; Salazar-Hermenegildo, N; Ramos-Garcia, R; Munoz-Lopez, J; Huang, Y C; Choi, B

2010-01-01

Speckle-based methods have been developed to characterize tissue blood flow and perfusion. One such method, called modified laser speckle imaging (mLSI), enables computation of blood flow maps with relatively high spatial resolution. Although it is known that the sensitivity and noise in LSI measurements depend on image exposure time, a fundamental disadvantage of mLSI is that it does not take into account this parameter. In this work, we integrate the exposure time into the mLSI method and provide experimental support of our approach with measurements from an in vitro flow phantom.

Advanced methods for image registration applied to JET videos

Energy Technology Data Exchange (ETDEWEB)

Craciunescu, Teddy, E-mail: teddy.craciunescu@jet.uk [EURATOM-MEdC Association, NILPRP, Bucharest (Romania); Murari, Andrea [Consorzio RFX, Associazione EURATOM-ENEA per la Fusione, Padova (Italy); Gelfusa, Michela [Associazione EURATOM-ENEA – University of Rome “Tor Vergata”, Roma (Italy); Tiseanu, Ion; Zoita, Vasile [EURATOM-MEdC Association, NILPRP, Bucharest (Romania); Arnoux, Gilles [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon (United Kingdom)

2015-10-15

Graphical abstract: - Highlights: • Development of an image registration method for JET IR and fast visible cameras. • Method based on SIFT descriptors and coherent point drift points set registration technique. • Method able to deal with extremely noisy images and very low luminosity images. • Computation time compatible with the inter-shot analysis. - Abstract: The last years have witnessed a significant increase in the use of digital cameras on JET. They are routinely applied for imaging in the IR and visible spectral regions. One of the main technical difficulties in interpreting the data of camera based diagnostics is the presence of movements of the field of view. Small movements occur due to machine shaking during normal pulses while large ones may arise during disruptions. Some cameras show a correlation of image movement with change of magnetic field strength. For deriving unaltered information from the videos and for allowing correct interpretation an image registration method, based on highly distinctive scale invariant feature transform (SIFT) descriptors and on the coherent point drift (CPD) points set registration technique, has been developed. The algorithm incorporates a complex procedure for rejecting outliers. The method has been applied for vibrations correction to videos collected by the JET wide angle infrared camera and for the correction of spurious rotations in the case of the JET fast visible camera (which is equipped with an image intensifier). The method has proved to be able to deal with the images provided by this camera frequently characterized by low contrast and a high level of blurring and noise.

Training Methods for Image Noise Level Estimation on Wavelet Components

Directory of Open Access Journals (Sweden)

A. De Stefano

2004-12-01

Full Text Available The estimation of the standard deviation of noise contaminating an image is a fundamental step in wavelet-based noise reduction techniques. The method widely used is based on the mean absolute deviation (MAD. This model-based method assumes specific characteristics of the noise-contaminated image component. Three novel and alternative methods for estimating the noise standard deviation are proposed in this work and compared with the MAD method. Two of these methods rely on a preliminary training stage in order to extract parameters which are then used in the application stage. The sets used for training and testing, 13 and 5 images, respectively, are fully disjoint. The third method assumes specific statistical distributions for image and noise components. Results showed the prevalence of the training-based methods for the images and the range of noise levels considered.

Sonography, CT and MR in soft part growths in the head and neck region

International Nuclear Information System (INIS)

Brinkmann, G.; Brix, F.; Beigel, A.

1990-01-01

14 patients with a space-occupying growth in the head and neck region were examined via sonography, CT and MR to explore and demonstrate by means of a prospective comparative study the possibilities offered by these three imaging methods. Stages are best diagnosed by means of sonography; the leading role of this method is undisputed. To clarify sonographically unclear findings and especially in pre-surgery planning, MR offers advantages over CT on account of the high soft-part contrast and multiplanar visualisation. However, it is impossible or very difficult to differentiate abscesses and lymphadenitides from malignant growths with these three methods solely on the basis of image-morphological criteria. (orig.) [de

Fusion of SPECT/TC images: Usefulness and benefits in degenerative spinal cord pathology

International Nuclear Information System (INIS)

Ocampo, Monica; Ucros, Gonzalo; Bermudez, Sonia; Morillo, Anibal; Rodriguez, Andres

2005-01-01

The objectives are to compare CT and SPECT bone scintigraphy evaluated independently with SPECT-CT fusion images in patients with known degenerative spinal pathology. To demonstrate the clinical usefulness of CT and SPECT fusion images. Materials and methods: Thirty-one patients with suspected degenerative spinal disease were evaluated with thin-slice, non-angled helical CT and bone scintigrams with single photon emission computed tomography (SPECT), both with multiplanar reconstructions within a 24-hour period After independent evaluation by a nuclear medicine specialist and a radiologist, multimodality image fusion software was used to merge the CT and SPECT studies and a final consensus interpretation of the combined images was obtained. Results: Thirty-two SPECT bone scintigraphy images, helical CT studies and SPECT-CT fusion images were obtained for 31 patients with degenerative spinal disease. The results of the bone scintigraphy and CT scans were in agreement in 17 pairs of studies (53.12%). In these studies image fusion did not provide additional information on the location or extension of the lesions. In 11 of the study pairs (34.2%), the information obtained was not in agreement between scintigraphy and CT studies: CT images demonstrated several abnormalities, whereas the SPECT images showed only one dominant lesion, or the SPECT images did not provide enough information for anatomical localization. In these cases image fusion helped establish the precise localization of the most clinically significant lesion, which matched the lesion with the greatest uptake. In 4 studies (12.5%) the CT and SPECT images were not in agreement: CT and SPECT images showed different information (normal scintigraphy, abnormal CT), thus leading to inconclusive fusion images. Conclusion: The use of CT-SPECT fusion images in degenerative spinal disease allows for the integration of anatomic detail with physiologic and functional information. CT-SPECT fusion improves the

Methods for processing and analysis functional and anatomical brain images: computerized tomography, emission tomography and nuclear resonance imaging

International Nuclear Information System (INIS)

Mazoyer, B.M.

1988-01-01

The various methods for brain image processing and analysis are presented and compared. The following topics are developed: the physical basis of brain image comparison (nature and formation of signals intrinsic performance of the methods image characteristics); mathematical methods for image processing and analysis (filtering, functional parameter extraction, morphological analysis, robotics and artificial intelligence); methods for anatomical localization (neuro-anatomy atlas, proportional stereotaxic atlas, numerized atlas); methodology of cerebral image superposition (normalization, retiming); image networks [fr

Synthesis and assessment methods for an edge-alignment-free hybrid image

Science.gov (United States)

Sripian, Peeraya; Yamaguchi, Yasushi

2017-07-01

A hybrid image allows multiple image interpretations to be modulated by the viewing distance. It can be constructed on the basis of the multiscale perceptual mechanisms of the human visual system by combining the low and high spatial frequencies of two different images. The hybrid image was introduced as an experimental tool for visual recognition study in terms of spatial frequency perception. To produce a compelling hybrid image, the original hybrid image synthesis method could only use similar shapes of source images that were aligned in the edges. If any two different images can be hybrid, it would be beneficial as a new experimental tool. In addition, there is no measure for the actual perception of spatial frequency, whether a single spatial frequency or both spatial frequencies are perceived from the hybrid stimulus. This paper describes two methods for synthesizing a hybrid image from dissimilar shape images or unaligned images; this hybrid image is known as an "edge-alignment-free hybrid image." A noise-inserted method can be done by intentionally inserting and enhancing noises into the high-frequency image. With this method, the low-frequency blobs are covered with high-frequency noises when viewed up close. A color-inserted method uses complementary color gratings in the background of the high-frequency image to emphasize the high-frequency image when viewed up close, whereas the gratings disappear when viewed from far away. To ascertain that our approach successfully separates the spatial frequency at each viewing distance, we measured this property using our proposed assessment method. Our proposed method allows the experimenter to quantify the probability of perceiving both spatial frequencies and a single spatial frequency in a hybrid image. The experimental results confirmed that our proposed synthesis methods successfully hid the low-frequency image and emphasized the high-frequency image at a close viewing distance. At the same time, the

Medical Imaging Image Quality Assessment with Monte Carlo Methods

International Nuclear Information System (INIS)

Michail, C M; Fountos, G P; Kalyvas, N I; Valais, I G; Kandarakis, I S; Karpetas, G E; Martini, Niki; Koukou, Vaia

2015-01-01

The aim of the present study was to assess image quality of PET scanners through a thin layer chromatography (TLC) plane source. The source was simulated using a previously validated Monte Carlo model. The model was developed by using the GATE MC package and reconstructed images obtained with the STIR software for tomographic image reconstruction, with cluster computing. The PET scanner simulated in this study was the GE DiscoveryST. A plane source consisted of a TLC plate, was simulated by a layer of silica gel on aluminum (Al) foil substrates, immersed in 18F-FDG bath solution (1MBq). Image quality was assessed in terms of the Modulation Transfer Function (MTF). MTF curves were estimated from transverse reconstructed images of the plane source. Images were reconstructed by the maximum likelihood estimation (MLE)-OSMAPOSL algorithm. OSMAPOSL reconstruction was assessed by using various subsets (3 to 21) and iterations (1 to 20), as well as by using various beta (hyper) parameter values. MTF values were found to increase up to the 12th iteration whereas remain almost constant thereafter. MTF improves by using lower beta values. The simulated PET evaluation method based on the TLC plane source can be also useful in research for the further development of PET and SPECT scanners though GATE simulations. (paper)

Multi-crack imaging using nonclassical nonlinear acoustic method

International Nuclear Information System (INIS)

Zhang Lue; Zhang Ying; Liu Xiao-Zhou; Gong Xiu-Fen

2014-01-01

Solid materials with cracks exhibit the nonclassical nonlinear acoustical behavior. The micro-defects in solid materials can be detected by nonlinear elastic wave spectroscopy (NEWS) method with a time-reversal (TR) mirror. While defects lie in viscoelastic solid material with different distances from one another, the nonlinear and hysteretic stress—strain relation is established with Preisach—Mayergoyz (PM) model in crack zone. Pulse inversion (PI) and TR methods are used in numerical simulation and defect locations can be determined from images obtained by the maximum value. Since false-positive defects might appear and degrade the imaging when the defects are located quite closely, the maximum value imaging with a time window is introduced to analyze how defects affect each other and how the fake one occurs. Furthermore, NEWS-TR-NEWS method is put forward to improve NEWS-TR scheme, with another forward propagation (NEWS) added to the existing phases (NEWS and TR). In the added phase, scanner locations are determined by locations of all defects imaged in previous phases, so that whether an imaged defect is real can be deduced. NEWS-TR-NEWS method is proved to be effective to distinguish real defects from the false-positive ones. Moreover, it is also helpful to detect the crack that is weaker than others during imaging procedure. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

Radiographic imaging method by gas ionisation

International Nuclear Information System (INIS)

Eickel, R.; Rheude, A.

1982-02-01

The search for a substitute of the silver halide film has been intensified worldwide due to the shortage and price increase of silver metal. Gasionography could be an alternative to the wellknown silver film imaging techniques in roentgenology. Therefore the practical basis of the imaging process and the electrophoretic development was investigated. The technical realisation of this method was demonstrated for two different types of X-ray examen by developing a fully automatic chest changer and a mammography system that can be adapted to commercially available imaging stands. The image quality achieved with these apparatus was evaluated in comparison with conventional film techniques in the laboratory as well as in a clinical trial. (orig.) [de

Image quality enhancement in low-light-level ghost imaging using modified compressive sensing method

Science.gov (United States)

Shi, Xiaohui; Huang, Xianwei; Nan, Suqin; Li, Hengxing; Bai, Yanfeng; Fu, Xiquan

2018-04-01

Detector noise has a significantly negative impact on ghost imaging at low light levels, especially for existing recovery algorithm. Based on the characteristics of the additive detector noise, a method named modified compressive sensing ghost imaging is proposed to reduce the background imposed by the randomly distributed detector noise at signal path. Experimental results show that, with an appropriate choice of threshold value, modified compressive sensing ghost imaging algorithm can dramatically enhance the contrast-to-noise ratio of the object reconstruction significantly compared with traditional ghost imaging and compressive sensing ghost imaging methods. The relationship between the contrast-to-noise ratio of the reconstruction image and the intensity ratio (namely, the average signal intensity to average noise intensity ratio) for the three reconstruction algorithms are also discussed. This noise suppression imaging technique will have great applications in remote-sensing and security areas.

Investigation of Optimal Integrated Circuit Raster Image Vectorization Method

Directory of Open Access Journals (Sweden)

Leonas Jasevičius

2011-03-01

Full Text Available Visual analysis of integrated circuit layer requires raster image vectorization stage to extract layer topology data to CAD tools. In this paper vectorization problems of raster IC layer images are presented. Various line extraction from raster images algorithms and their properties are discussed. Optimal raster image vectorization method was developed which allows utilization of common vectorization algorithms to achieve the best possible extracted vector data match with perfect manual vectorization results. To develop the optimal method, vectorized data quality dependence on initial raster image skeleton filter selection was assessed.Article in Lithuanian

Analyses of the eustachian tube and its surrounding tissues with cross sectional images by high-resolution computed tomography (HR-CT)

International Nuclear Information System (INIS)

Yoshida, Haruo; Kobayashi, Toshimitsu; Takasaki, Kenji; Kanda, Yukihiko; Nakao, Yoshiaki; Morikawa, Minoru; Ishimaru, Hideki; Hayashi, Kuniaki

2000-01-01

We attempted to image the eustachian tube (ET) and its surrounding tissues by high-resolution computed tomography (HR-CT). Twenty-two normal subjects (44 ears) without middle ear problems were studied, and a patient with severe patulous ET was also studied as an abnormal case. In our device of multiplanar reconstruction technique, we were able to obtain the clear reconstructed images of the ET lumen as well as of its surrounding tissues (bone, ET cartilage, tensor veli palatini muscle, levator veli palatini muscle, Ostmann's fat tissue, tensor tympani muscle, internal carotid artery) at any desired portion, either parallel or perpendicular to the long axis of the ET. However, the exact borders between the ET cartilage and the muscles, Ostmann's fat tissue and the tubal gland were not clearly identified. In the severe case of patulous ET, the ET lumen was widely opened at each cross-sectional image from the pharyngeal orifice to the tympanic orifice, in contrast with its being closed at the cartilaginous portion in the normal cases. In addition, the fat tissue and glands around the ET lumen were not clearly identified in this case. We suggest that this method will lead to better understanding of the ET-related diseases such as patulous ET. (author)

Analyses of the eustachian tube and its surrounding tissues with cross sectional images by high-resolution computed tomography (HR-CT)

Energy Technology Data Exchange (ETDEWEB)

Yoshida, Haruo; Kobayashi, Toshimitsu; Takasaki, Kenji; Kanda, Yukihiko; Nakao, Yoshiaki; Morikawa, Minoru; Ishimaru, Hideki; Hayashi, Kuniaki [Nagasaki Univ. (Japan). School of Medicine

2000-07-01

We attempted to image the eustachian tube (ET) and its surrounding tissues by high-resolution computed tomography (HR-CT). Twenty-two normal subjects (44 ears) without middle ear problems were studied, and a patient with severe patulous ET was also studied as an abnormal case. In our device of multiplanar reconstruction technique, we were able to obtain the clear reconstructed images of the ET lumen as well as of its surrounding tissues (bone, ET cartilage, tensor veli palatini muscle, levator veli palatini muscle, Ostmann's fat tissue, tensor tympani muscle, internal carotid artery) at any desired portion, either parallel or perpendicular to the long axis of the ET. However, the exact borders between the ET cartilage and the muscles, Ostmann's fat tissue and the tubal gland were not clearly identified. In the severe case of patulous ET, the ET lumen was widely opened at each cross-sectional image from the pharyngeal orifice to the tympanic orifice, in contrast with its being closed at the cartilaginous portion in the normal cases. In addition, the fat tissue and glands around the ET lumen were not clearly identified in this case. We suggest that this method will lead to better understanding of the ET-related diseases such as patulous ET. (author)

A new method of the light irradiation image by the computed radiography (imaging plate) system

International Nuclear Information System (INIS)

Aiba, Susumu; Nishi, Katsuki.

1997-01-01

There are two method for the purpose of diagnosing medically by using gamma-ray light irradiation image. One is to use of the scintillation camera for gamma-ray, the other is to use of the photostimulable luminescence point by the secondary excitation of the image plate (IP) system for X-ray. The standpoint of the spatial resolution at the total medical image, using gamma-ray, the first can get the image on a short time, but the first is a poor image quality, and the second is good image quality, but the second can get the image on a long time, because of insensitive to gamma-ray. We report on the improvement for IP's week point by our proposal method, and by our clinical and quantitative analysis data, to use the highly efficient IP (ST-III). We make the improvement on the imaging time (from 30 minutes to 20 minutes), and the inprocessing time (from 33-50 minutes to 27 minutes) for a former method on an organism. We strongly believe that our convenience improvement method, and our clinical quantitative analysis data can contribute to the wide application as well as the quality up for the clinical diagnosis to use gamma-ray. (author)

Level set method for image segmentation based on moment competition

Science.gov (United States)

Min, Hai; Wang, Xiao-Feng; Huang, De-Shuang; Jin, Jing; Wang, Hong-Zhi; Li, Hai

2015-05-01

We propose a level set method for image segmentation which introduces the moment competition and weakly supervised information into the energy functional construction. Different from the region-based level set methods which use force competition, the moment competition is adopted to drive the contour evolution. Here, a so-called three-point labeling scheme is proposed to manually label three independent points (weakly supervised information) on the image. Then the intensity differences between the three points and the unlabeled pixels are used to construct the force arms for each image pixel. The corresponding force is generated from the global statistical information of a region-based method and weighted by the force arm. As a result, the moment can be constructed and incorporated into the energy functional to drive the evolving contour to approach the object boundary. In our method, the force arm can take full advantage of the three-point labeling scheme to constrain the moment competition. Additionally, the global statistical information and weakly supervised information are successfully integrated, which makes the proposed method more robust than traditional methods for initial contour placement and parameter setting. Experimental results with performance analysis also show the superiority of the proposed method on segmenting different types of complicated images, such as noisy images, three-phase images, images with intensity inhomogeneity, and texture images.

Optical image encryption method based on incoherent imaging and polarized light encoding

Science.gov (United States)

Wang, Q.; Xiong, D.; Alfalou, A.; Brosseau, C.

2018-05-01

We propose an incoherent encoding system for image encryption based on a polarized encoding method combined with an incoherent imaging. Incoherent imaging is the core component of this proposal, in which the incoherent point-spread function (PSF) of the imaging system serves as the main key to encode the input intensity distribution thanks to a convolution operation. An array of retarders and polarizers is placed on the input plane of the imaging structure to encrypt the polarized state of light based on Mueller polarization calculus. The proposal makes full use of randomness of polarization parameters and incoherent PSF so that a multidimensional key space is generated to deal with illegal attacks. Mueller polarization calculus and incoherent illumination of imaging structure ensure that only intensity information is manipulated. Another key advantage is that complicated processing and recording related to a complex-valued signal are avoided. The encoded information is just an intensity distribution, which is advantageous for data storage and transition because information expansion accompanying conventional encryption methods is also avoided. The decryption procedure can be performed digitally or using optoelectronic devices. Numerical simulation tests demonstrate the validity of the proposed scheme.

Imaging the cranial nerves: part II: primary and secondary neoplastic conditions and neurovascular conflicts

International Nuclear Information System (INIS)

Borges, Alexandra; Casselman, Jan

2007-01-01

There have been unprecedented improvements in cross-sectional imaging in the last decades. The emergence of volumetric CT, higher field MR scanners and higher resolution MR sequences is largely responsible for the increasing diagnostic yield of imaging in patients presenting with cranial nerve deficits. The introduction of parallel MR imaging in combination with small surface coils allows the depiction of submillimetric nerves and nerve branches, and volumetric CT and MR imaging is able to provide high quality multiplanar and curved reconstructions that can follow the often complex course of cranial nerves. Seeking the cause of a cranial nerve deficit is a common indication for imaging, and it is not uncommon that radiologists are the first specialists to see a patient with a cranial neuropathy. To increase the diagnostic yield of imaging, high-resolution studies with smaller fields of view are required. To keep imaging studies within a reasonable time frame, it is mandatory to tailor the study according to neuro-topographic testing. This review article focuses on the contribution of current imaging techniques in the depiction of primary and secondary neoplastic conditions affecting the cranial nerves as well as on neurovascular conflicts, an increasingly recognized cause of cranial neuralgias. (orig.)

Imaging the cranial nerves: part II: primary and secondary neoplastic conditions and neurovascular conflicts

Energy Technology Data Exchange (ETDEWEB)

Borges, Alexandra [Instituto Portugues de Oncologia Francisco Gentil- Centro de Lisboa, Radiology Department, Lisboa Codex (Portugal); Casselman, Jan [A. Z. St Jan Brugge and A. Z. St Augustinus Antwerpen Hospitals, Department of Radiology, Antwerp (Belgium)

2007-09-15

There have been unprecedented improvements in cross-sectional imaging in the last decades. The emergence of volumetric CT, higher field MR scanners and higher resolution MR sequences is largely responsible for the increasing diagnostic yield of imaging in patients presenting with cranial nerve deficits. The introduction of parallel MR imaging in combination with small surface coils allows the depiction of submillimetric nerves and nerve branches, and volumetric CT and MR imaging is able to provide high quality multiplanar and curved reconstructions that can follow the often complex course of cranial nerves. Seeking the cause of a cranial nerve deficit is a common indication for imaging, and it is not uncommon that radiologists are the first specialists to see a patient with a cranial neuropathy. To increase the diagnostic yield of imaging, high-resolution studies with smaller fields of view are required. To keep imaging studies within a reasonable time frame, it is mandatory to tailor the study according to neuro-topographic testing. This review article focuses on the contribution of current imaging techniques in the depiction of primary and secondary neoplastic conditions affecting the cranial nerves as well as on neurovascular conflicts, an increasingly recognized cause of cranial neuralgias. (orig.)

A novel magnetic resonance imaging-compatible motor control method for image-guided robotic surgery

International Nuclear Information System (INIS)

Suzuki, Takashi; Liao, Hongen; Kobayashi, Etsuko; Sakuma, Ichiro

2006-01-01

For robotic surgery assistance systems that use magnetic resonance imaging (MRI) for guidance, the problem of electromagnetic interference is common. Image quality is particularly degraded if motors are running during scanning. We propose a novel MRI-compatible method considering the pulse sequence of imaging. Motors are driven for a short time when the MRI system stops signal acquisition (i.e., awaiting relaxation of the proton), so the image does not contain noise from the actuators. The MRI system and motor are synchronized using a radio frequency pulse signal (8.5 MHz) as the trigger, which is acquired via a special antenna mounted near the scanner. This method can be widely applied because it only receives part of the scanning signal and neither hardware nor software of the MRI system needs to be changed. As a feasibility evaluation test, we compared the images and signal-to-noise ratios between the cases with and without this method, under the condition that a piezoelectric motor was driven during scanning as a noise source, which was generally used as a MRI-compatible actuator. The results showed no deterioration in image quality and the benefit of the new method even though the choice of available scanning sequences is limited. (author)

Development of a practical image-based scatter correction method for brain perfusion SPECT: comparison with the TEW method

International Nuclear Information System (INIS)

Shidahara, Miho; Kato, Takashi; Kawatsu, Shoji; Yoshimura, Kumiko; Ito, Kengo; Watabe, Hiroshi; Kim, Kyeong Min; Iida, Hidehiro; Kato, Rikio

2005-01-01

An image-based scatter correction (IBSC) method was developed to convert scatter-uncorrected into scatter-corrected SPECT images. The purpose of this study was to validate this method by means of phantom simulations and human studies with 99m Tc-labeled tracers, based on comparison with the conventional triple energy window (TEW) method. The IBSC method corrects scatter on the reconstructed image I AC μb with Chang's attenuation correction factor. The scatter component image is estimated by convolving I AC μb with a scatter function followed by multiplication with an image-based scatter fraction function. The IBSC method was evaluated with Monte Carlo simulations and 99m Tc-ethyl cysteinate dimer SPECT human brain perfusion studies obtained from five volunteers. The image counts and contrast of the scatter-corrected images obtained by the IBSC and TEW methods were compared. Using data obtained from the simulations, the image counts and contrast of the scatter-corrected images obtained by the IBSC and TEW methods were found to be nearly identical for both gray and white matter. In human brain images, no significant differences in image contrast were observed between the IBSC and TEW methods. The IBSC method is a simple scatter correction technique feasible for use in clinical routine. (orig.)

Development of a practical image-based scatter correction method for brain perfusion SPECT: comparison with the TEW method.

Science.gov (United States)

Shidahara, Miho; Watabe, Hiroshi; Kim, Kyeong Min; Kato, Takashi; Kawatsu, Shoji; Kato, Rikio; Yoshimura, Kumiko; Iida, Hidehiro; Ito, Kengo

2005-10-01

An image-based scatter correction (IBSC) method was developed to convert scatter-uncorrected into scatter-corrected SPECT images. The purpose of this study was to validate this method by means of phantom simulations and human studies with 99mTc-labeled tracers, based on comparison with the conventional triple energy window (TEW) method. The IBSC method corrects scatter on the reconstructed image I(mub)AC with Chang's attenuation correction factor. The scatter component image is estimated by convolving I(mub)AC with a scatter function followed by multiplication with an image-based scatter fraction function. The IBSC method was evaluated with Monte Carlo simulations and 99mTc-ethyl cysteinate dimer SPECT human brain perfusion studies obtained from five volunteers. The image counts and contrast of the scatter-corrected images obtained by the IBSC and TEW methods were compared. Using data obtained from the simulations, the image counts and contrast of the scatter-corrected images obtained by the IBSC and TEW methods were found to be nearly identical for both gray and white matter. In human brain images, no significant differences in image contrast were observed between the IBSC and TEW methods. The IBSC method is a simple scatter correction technique feasible for use in clinical routine.

System and method for image mapping and visual attention

Science.gov (United States)

Peters, II, Richard A. (Inventor)

2011-01-01

A method is described for mapping dense sensory data to a Sensory Ego Sphere (SES). Methods are also described for finding and ranking areas of interest in the images that form a complete visual scene on an SES. Further, attentional processing of image data is best done by performing attentional processing on individual full-size images from the image sequence, mapping each attentional location to the nearest node, and then summing all attentional locations at each node.

Simplifying the exploration of volumetric images: development of a 3D user interface for the radiologist's workplace.

Science.gov (United States)

Teistler, M; Breiman, R S; Lison, T; Bott, O J; Pretschner, D P; Aziz, A; Nowinski, W L

2008-10-01

Volumetric imaging (computed tomography and magnetic resonance imaging) provides increased diagnostic detail but is associated with the problem of navigation through large amounts of data. In an attempt to overcome this problem, a novel 3D navigation tool has been designed and developed that is based on an alternative input device. A 3D mouse allows for simultaneous definition of position and orientation of orthogonal or oblique multiplanar reformatted images or slabs, which are presented within a virtual 3D scene together with the volume-rendered data set and additionally as 2D images. Slabs are visualized with maximum intensity projection, average intensity projection, or standard volume rendering technique. A prototype has been implemented based on PC technology that has been tested by several radiologists. It has shown to be easily understandable and usable after a very short learning phase. Our solution may help to fully exploit the diagnostic potential of volumetric imaging by allowing for a more efficient reading process compared to currently deployed solutions based on conventional mouse and keyboard.

Hiding a Covert Digital Image by Assembling the RSA Encryption Method and the Binary Encoding Method

OpenAIRE

Kuang Tsan Lin; Sheng Lih Yeh

2014-01-01

The Rivest-Shamir-Adleman (RSA) encryption method and the binary encoding method are assembled to form a hybrid hiding method to hide a covert digital image into a dot-matrix holographic image. First, the RSA encryption method is used to transform the covert image to form a RSA encryption data string. Then, all the elements of the RSA encryption data string are transferred into binary data. Finally, the binary data are encoded into the dot-matrix holographic image. The pixels of the dot-matri...

Sampling methods for low-frequency electromagnetic imaging

International Nuclear Information System (INIS)

Gebauer, Bastian; Hanke, Martin; Schneider, Christoph

2008-01-01

For the detection of hidden objects by low-frequency electromagnetic imaging the linear sampling method works remarkably well despite the fact that the rigorous mathematical justification is still incomplete. In this work, we give an explanation for this good performance by showing that in the low-frequency limit the measurement operator fulfils the assumptions for the fully justified variant of the linear sampling method, the so-called factorization method. We also show how the method has to be modified in the physically relevant case of electromagnetic imaging with divergence-free currents. We present numerical results to illustrate our findings, and to show that similar performance can be expected for the case of conducting objects and layered backgrounds

General filtering method for electronic speckle pattern interferometry fringe images with various densities based on variational image decomposition.

Science.gov (United States)

Li, Biyuan; Tang, Chen; Gao, Guannan; Chen, Mingming; Tang, Shuwei; Lei, Zhenkun

2017-06-01

Filtering off speckle noise from a fringe image is one of the key tasks in electronic speckle pattern interferometry (ESPI). In general, ESPI fringe images can be divided into three categories: low-density fringe images, high-density fringe images, and variable-density fringe images. In this paper, we first present a general filtering method based on variational image decomposition that can filter speckle noise for ESPI fringe images with various densities. In our method, a variable-density ESPI fringe image is decomposed into low-density fringes, high-density fringes, and noise. A low-density fringe image is decomposed into low-density fringes and noise. A high-density fringe image is decomposed into high-density fringes and noise. We give some suitable function spaces to describe low-density fringes, high-density fringes, and noise, respectively. Then we construct several models and numerical algorithms for ESPI fringe images with various densities. And we investigate the performance of these models via our extensive experiments. Finally, we compare our proposed models with the windowed Fourier transform method and coherence enhancing diffusion partial differential equation filter. These two methods may be the most effective filtering methods at present. Furthermore, we use the proposed method to filter a collection of the experimentally obtained ESPI fringe images with poor quality. The experimental results demonstrate the performance of our proposed method.

Image Mosaic Method Based on SIFT Features of Line Segment

Directory of Open Access Journals (Sweden)

Jun Zhu

2014-01-01

Full Text Available This paper proposes a novel image mosaic method based on SIFT (Scale Invariant Feature Transform feature of line segment, aiming to resolve incident scaling, rotation, changes in lighting condition, and so on between two images in the panoramic image mosaic process. This method firstly uses Harris corner detection operator to detect key points. Secondly, it constructs directed line segments, describes them with SIFT feature, and matches those directed segments to acquire rough point matching. Finally, Ransac method is used to eliminate wrong pairs in order to accomplish image mosaic. The results from experiment based on four pairs of images show that our method has strong robustness for resolution, lighting, rotation, and scaling.

COMPARISON OF DIGITAL IMAGE STEGANOGRAPHY METHODS

Directory of Open Access Journals (Sweden)

S. A. Seyyedi

2013-01-01

Full Text Available Steganography is a method of hiding information in other information of different format (container. There are many steganography techniques with various types of container. In the Internet, digital images are the most popular and frequently used containers. We consider main image steganography techniques and their advantages and disadvantages. We also identify the requirements of a good steganography algorithm and compare various such algorithms.

Diagnostic Value of Multidetector CT and Its Multiplanar Reformation, Volume Rendering and Virtual Bronchoscopy Postprocessing Techniques for Primary Trachea and Main Bronchus Tumors.

Directory of Open Access Journals (Sweden)

Mingyue Luo

without obvious enhancement, n = 1.MDCT and its MPR, VR and VB images have respective advantages and disadvantages. Their combination could complement to each other to accurately detect locations, natures (benignancy, malignancy or low malignancy, and quantities (extramural invasions, longitudinal involvements, extents of luminal stenoses, distances between main bronchus tumors and trachea carinae of primary trachea and main bronchus tumors with crucial information for surgical treatment, are highly useful diagnostic methods for primary trachea and main bronchus tumors.

Diagnostic Value of Multidetector CT and Its Multiplanar Reformation, Volume Rendering and Virtual Bronchoscopy Postprocessing Techniques for Primary Trachea and Main Bronchus Tumors.

Science.gov (United States)

Luo, Mingyue; Duan, Chaijie; Qiu, Jianping; Li, Wenru; Zhu, Dongyun; Cai, Wenli

2015-01-01

obvious enhancement, n = 1). MDCT and its MPR, VR and VB images have respective advantages and disadvantages. Their combination could complement to each other to accurately detect locations, natures (benignancy, malignancy or low malignancy), and quantities (extramural invasions, longitudinal involvements, extents of luminal stenoses, distances between main bronchus tumors and trachea carinae) of primary trachea and main bronchus tumors with crucial information for surgical treatment, are highly useful diagnostic methods for primary trachea and main bronchus tumors.

The usefulness of three-dimensional imaging with spiral CT in the evaluation of upper airway stenosis

Energy Technology Data Exchange (ETDEWEB)

Jang, Won Ho; Yoon, Dae Young; Bae, Sang Hoon; Rho, Young Soo; Jung, Yin Gyo [Hallym Univ. College of Medicine, Seoul (Korea, Republic of)

1996-01-01

To assess the usefulness of three-dimensional (3D) spiral CT imaging in patients with upper airway stenosis. We performed 3D spiral CT imagings in ten patients in whom upper airway stenosis was clinically suspected. Eight of these patients had upper airway stenosis caused by intubation or tracheostomy (n-6), tuberculosis (n=1), or extrinsic compression by a thyroid mass (n=1). Spiral CT scanning (30-second continuous exposure and 90-mm length) was performed with a table speed of 3mm/sec and a section thickness of 3mm. The selected starting point was the epiglottis. The resulting data were reformatted by multiplanar reformation (MPR) and shaded surface display (SSD) with peeling after reconstruction of 2mm interval. In the evaluation of location and extent of stenosis, we compared fidings of 3D imaging with those of baseline axial images (n=10), endoscopy (n=9) and operation (n=4). The locations of stenosis in eight patients were as follows;tracheostoma (n=4), subglottic region (n=3), and larynx (n=1). In all eight, 3D imaging demonstrated the location and extent of stenosis, which exactly correlated with endoscopic and operative findings. In one patient, however, another stenotic area in the tracheal bifurcation was not discovered because this lesion was not included in the field of CT scan. In two patients, the diagnosis on 3D images of no 'stenosis' was comfirmed by clinical findings or operation. No differences in diagnostic accuracy were noted between axial images, MPR, and SSD when evalvating the location and extent of stenosis; vertical extent was shown more easily by 3D imaging than by axial images, however. 3D imaging with spiral CT may be an useful adjunctive method in the evaluation of upper airway stenosis with variable causes.

The usefulness of three-dimensional imaging with spiral CT in the evaluation of upper airway stenosis

International Nuclear Information System (INIS)

Jang, Won Ho; Yoon, Dae Young; Bae, Sang Hoon; Rho, Young Soo; Jung, Yin Gyo

1996-01-01

To assess the usefulness of three-dimensional (3D) spiral CT imaging in patients with upper airway stenosis. We performed 3D spiral CT imagings in ten patients in whom upper airway stenosis was clinically suspected. Eight of these patients had upper airway stenosis caused by intubation or tracheostomy (n-6), tuberculosis (n=1), or extrinsic compression by a thyroid mass (n=1). Spiral CT scanning (30-second continuous exposure and 90-mm length) was performed with a table speed of 3mm/sec and a section thickness of 3mm. The selected starting point was the epiglottis. The resulting data were reformatted by multiplanar reformation (MPR) and shaded surface display (SSD) with peeling after reconstruction of 2mm interval. In the evaluation of location and extent of stenosis, we compared fidings of 3D imaging with those of baseline axial images (n=10), endoscopy (n=9) and operation (n=4). The locations of stenosis in eight patients were as follows;tracheostoma (n=4), subglottic region (n=3), and larynx (n=1). In all eight, 3D imaging demonstrated the location and extent of stenosis, which exactly correlated with endoscopic and operative findings. In one patient, however, another stenotic area in the tracheal bifurcation was not discovered because this lesion was not included in the field of CT scan. In two patients, the diagnosis on 3D images of no 'stenosis' was comfirmed by clinical findings or operation. No differences in diagnostic accuracy were noted between axial images, MPR, and SSD when evalvating the location and extent of stenosis; vertical extent was shown more easily by 3D imaging than by axial images, however. 3D imaging with spiral CT may be an useful adjunctive method in the evaluation of upper airway stenosis with variable causes

Mediastinal and hilar lymphadenopathy: cross-referenced anatomy on axial and coronal images displayed by using multi-detector row CT

International Nuclear Information System (INIS)

Lee, Ju Hyun; Lee, Kyung Soo; Kim, Tae Sung; Yi, Chin A; Cho, Jae Min; Lee, Min Hee

2003-01-01

The accurate evaluation of mediastinal and pulmonary hilar lymphadenopathy, especially in patients with lung cancer, is important for determining treatment options and evaluating the response to therapy. To indicate nodal location in detail, mediastinal and hilar lymph nodes have been assigned to one of 14 nodal stations. Mediastinal nodes of greater than 10 mm short-axis diameter are regarded as abnormal, irrespective of their nodal station, while hilar nodes are considered abnormal if their diameter is greater than 10 mm in any axis or they are convex compared to surrounding lung. By providing multiplanar images, multi-detector row CT allows detailed evaluation of thoracic anatomic structures more easily than in the past, when axial images only were available. At cross-referenced imaging, a lymph node depicted at axial imaging in one anatomical location can be visualized simultaneously and automatically at coronal imaging at the exactly corresponding anatomical location. Cross-referenced coincidental axial and coronal images help assess both the size and morphology of mediastinal and hilar lymph nodes

Measurement of cardiac ventricular volumes using multidetector row computed tomography: comparison of two- and three-dimensional methods

International Nuclear Information System (INIS)

Montaudon, M.; Laffon, E.; Berger, P.; Corneloup, O.; Latrabe, V.; Laurent, F.

2006-01-01

This study compared a three-dimensional volumetric threshold-based method to a two-dimensional Simpson's rule based short-axis multiplanar method for measuring right (RV) and left ventricular (LV) volumes, stroke volumes, and ejection fraction using electrocardiography-gated multidetector computed tomography (MDCT) data sets. End-diastolic volume (EDV) and end-systolic volume (ESV) of RV and LV were measured independently and blindly by two observers from contrast-enhanced MDCT images using commercial software in 18 patients. For RV and LV the three-dimensionally calculated EDV and ESV values were smaller than those provided by two-dimensional short axis (10%, 5%, 15% and 26% differences respectively). Agreement between the two methods was found for LV (EDV/ESV: r=0.974/0.910, ICC=0.905/0.890) but not for RV (r=0.882/0.930, ICC=0.663/0.544). Measurement errors were significant only for EDV of LV using the two-dimensional method. Similar reproducibility was found for LV measurements, but the three-dimensional method provided greater reproducibility for RV measurements than the two-dimensional. The threshold value supported three-dimensional method provides reproducible cardiac ventricular volume measurements, comparable to those obtained using the short-axis Simpson based method. (orig.)

Traumatic cervical root injury: Diagnostic value of MR imaging

International Nuclear Information System (INIS)

Lee, Seon Kyu; Chang, Kee Hyun; Han, Moon Hee; Kim, Ho Chul; Kim, Jea Seung; Cha, Sang Hoon

1993-01-01

Although superior soft tissue contrast and direct multiplanar imaging capability of MRI are well recognized, myelography has been the imaging modality of choice in evaluation cervical root injury. We assessed the role of MRI and compared its diagnostic accuracy with myelography in the evaluation of cervical root injury. MR imagings of cervical root injury in ten patients (55 roots) were retrospectively reviewed. In 26 explored roots (6 patients). MR findings were compared with myelography and surgical results. In 29 roots (8 patients), which were confirmed by myelography or exploration, the MR findings were focal extradural CSF collections (pseudomeningocele) in 21/29 (72.4%, 8 patients), thickening of extradural roots in 4/29 (13.6%, 5 patients), and thickening of dura in 12/29 (41.4%, 6 patients) roots. T2-weighted axial image was superior to T1-weighted and protein-density- weighted images for delineation root avulsion. The sensitivity and specificity of MRI were 72.7% and 93.3% respectively, while those of myelography were 83% and 90%. Overall diagnostic accuracy of MRI and myelography were comparable (84.6% vs 87.5%). In conclusion, myelography is still considered as the modality of choice in the preoperative evaluation of the cervical root avulsion because of its higher sensitivity. MRI, however, may obviate the myelography with some technical refinements

Blind compressed sensing image reconstruction based on alternating direction method

Science.gov (United States)

Liu, Qinan; Guo, Shuxu

2018-04-01

In order to solve the problem of how to reconstruct the original image under the condition of unknown sparse basis, this paper proposes an image reconstruction method based on blind compressed sensing model. In this model, the image signal is regarded as the product of a sparse coefficient matrix and a dictionary matrix. Based on the existing blind compressed sensing theory, the optimal solution is solved by the alternative minimization method. The proposed method solves the problem that the sparse basis in compressed sensing is difficult to represent, which restrains the noise and improves the quality of reconstructed image. This method ensures that the blind compressed sensing theory has a unique solution and can recover the reconstructed original image signal from a complex environment with a stronger self-adaptability. The experimental results show that the image reconstruction algorithm based on blind compressed sensing proposed in this paper can recover high quality image signals under the condition of under-sampling.

Research on image complexity evaluation method based on color information

Science.gov (United States)

Wang, Hao; Duan, Jin; Han, Xue-hui; Xiao, Bo

2017-11-01

In order to evaluate the complexity of a color image more effectively and find the connection between image complexity and image information, this paper presents a method to compute the complexity of image based on color information.Under the complexity ,the theoretical analysis first divides the complexity from the subjective level, divides into three levels: low complexity, medium complexity and high complexity, and then carries on the image feature extraction, finally establishes the function between the complexity value and the color characteristic model. The experimental results show that this kind of evaluation method can objectively reconstruct the complexity of the image from the image feature research. The experimental results obtained by the method of this paper are in good agreement with the results of human visual perception complexity,Color image complexity has a certain reference value.

Imaging systems and methods for obtaining and using biometric information

Science.gov (United States)

McMakin, Douglas L [Richland, WA; Kennedy, Mike O [Richland, WA

2010-11-30

Disclosed herein are exemplary embodiments of imaging systems and methods of using such systems. In one exemplary embodiment, one or more direct images of the body of a clothed subject are received, and a motion signature is determined from the one or more images. In this embodiment, the one or more images show movement of the body of the subject over time, and the motion signature is associated with the movement of the subject's body. In certain implementations, the subject can be identified based at least in part on the motion signature. Imaging systems for performing any of the disclosed methods are also disclosed herein. Furthermore, the disclosed imaging, rendering, and analysis methods can be implemented, at least in part, as one or more computer-readable media comprising computer-executable instructions for causing a computer to perform the respective methods.

Fast method of constructing image correlations to build a free network based on image multivocabulary trees

Science.gov (United States)

Zhan, Zongqian; Wang, Xin; Wei, Minglu

2015-05-01

In image-based three-dimensional (3-D) reconstruction, one topic of growing importance is how to quickly obtain a 3-D model from a large number of images. The retrieval of the correct and relevant images for the model poses a considerable technological challenge. The "image vocabulary tree" has been proposed as a method to search for similar images. However, a significant drawback of this approach is identified in its low time efficiency and barely satisfactory classification result. The method proposed is inspired by, and improves upon, some recent methods. Specifically, vocabulary quality is considered and multivocabulary trees are designed to improve the classification result. A marked improvement was, indeed, observed in our evaluation of the proposed method. To improve time efficiency, graphics processing unit (GPU) computer unified device architecture parallel computation is applied in the multivocabulary trees. The results of the experiments showed that the GPU was three to four times more efficient than the enumeration matching and CPU methods when the number of images is large. This paper presents a reliable reference method for the rapid construction of a free network to be used for the computing of 3-D information.

Development of a practical image-based scatter correction method for brain perfusion SPECT: comparison with the TEW method

Energy Technology Data Exchange (ETDEWEB)

Shidahara, Miho; Kato, Takashi; Kawatsu, Shoji; Yoshimura, Kumiko; Ito, Kengo [National Center for Geriatrics and Gerontology Research Institute, Department of Brain Science and Molecular Imaging, Obu, Aichi (Japan); Watabe, Hiroshi; Kim, Kyeong Min; Iida, Hidehiro [National Cardiovascular Center Research Institute, Department of Investigative Radiology, Suita (Japan); Kato, Rikio [National Center for Geriatrics and Gerontology, Department of Radiology, Obu (Japan)

2005-10-01

An image-based scatter correction (IBSC) method was developed to convert scatter-uncorrected into scatter-corrected SPECT images. The purpose of this study was to validate this method by means of phantom simulations and human studies with {sup 99m}Tc-labeled tracers, based on comparison with the conventional triple energy window (TEW) method. The IBSC method corrects scatter on the reconstructed image I{sub AC}{sup {mu}}{sup b} with Chang's attenuation correction factor. The scatter component image is estimated by convolving I{sub AC}{sup {mu}}{sup b} with a scatter function followed by multiplication with an image-based scatter fraction function. The IBSC method was evaluated with Monte Carlo simulations and {sup 99m}Tc-ethyl cysteinate dimer SPECT human brain perfusion studies obtained from five volunteers. The image counts and contrast of the scatter-corrected images obtained by the IBSC and TEW methods were compared. Using data obtained from the simulations, the image counts and contrast of the scatter-corrected images obtained by the IBSC and TEW methods were found to be nearly identical for both gray and white matter. In human brain images, no significant differences in image contrast were observed between the IBSC and TEW methods. The IBSC method is a simple scatter correction technique feasible for use in clinical routine. (orig.)

Iterative methods for dose reduction and image enhancement in tomography

Science.gov (United States)

Miao, Jianwei; Fahimian, Benjamin Pooya

2012-09-18

A system and method for creating a three dimensional cross sectional image of an object by the reconstruction of its projections that have been iteratively refined through modification in object space and Fourier space is disclosed. The invention provides systems and methods for use with any tomographic imaging system that reconstructs an object from its projections. In one embodiment, the invention presents a method to eliminate interpolations present in conventional tomography. The method has been experimentally shown to provide higher resolution and improved image quality parameters over existing approaches. A primary benefit of the method is radiation dose reduction since the invention can produce an image of a desired quality with a fewer number projections than seen with conventional methods.

Don’t get caught out! A rare case of a calcified urachal remnant mimicking a bladder calculus

Science.gov (United States)

Rodrigues, Jonathan Carl Luis; Gandhi, Sanjay

2013-01-01

Computer tomography through the kidneys, ureters and bladder (CT KUB) is the mainstay investigation of suspected renal tract calculi. However, several pathologies other than renal tract calculi can cause apparent urinary bladder calcification. We describe the case of a 45 year old man who presented with left sided renal colic. Prone CT KUB performed on admission revealed a calcified urachal remnant mimicking a urinary bladder calculus in the dependent portion of the urinary bladder, confirmed by reviewing the multi-planar reformatted images. This is the first reported case in the literature of this phenomenon. We discuss the importance of using multi-planar reformatted images (MPR) and maximum intensity projection images (MIP), as well as careful review of previous imaging, in making the correct diagnosis. We also discuss the differential diagnoses that should be considered when presented with urinary bladder calcification. PMID:23705044

Multiplanar and two-dimensional imaging of central airway stenting with multidetector computed tomography

Directory of Open Access Journals (Sweden)

Ozgul Mehmet

2012-08-01

Full Text Available Abstract Background Multidetector computed tomography (MDCT provides guidance for primary screening of the central airways. The aim of our study was assessing the contribution of multidetector computed tomography- two dimensional reconstruction in the management of patients with tracheobronchial stenosis prior to the procedure and during a short follow up period of 3 months after the endobronchial treatment. Methods This is a retrospective study with data collected from an electronic database and from the medical records. Patients evaluated with MDCT and who had undergone a stenting procedure were included. A Philips RSGDT 07605 model MDCT was used, and slice thickness, 3 mm; overlap, 1.5 mm; matrix, 512x512; mass, 90 and kV, 120 were evaluated. The diameters of the airways 10 mm proximal and 10 mm distal to the obstruction were measured and the stent diameter (D was determined from the average between D upper and D lower. Results Fifty-six patients, 14 (25% women and 42 (75% men, mean age 55.3 ± 13.2 years (range: 16-79 years, were assessed by MDCT and then treated with placement of an endobronchial stent. A computed tomography review was made with 6 detector Philips RSGDT 07605 multidetector computed tomography device. Endobronchial therapy was provided for the patients with endoluminal lesions. Stents were placed into the area of stenosis in patients with external compression after dilatation and debulking procedures had been carried out. In one patient the migration of a stent was detected during the follow up period by using MDCT. Conclusions MDCT helps to define stent size, length and type in patients who are suitable for endobronchial stinting. This is a non-invasive, reliable method that helps decisions about optimal stent size and position, thus reducing complications.

An imaging checklist for pre-FESS CT: framing a surgically relevant report

Energy Technology Data Exchange (ETDEWEB)

Vaid, S., E-mail: vaids@vsnl.co [Department of Radiology and Imaging, Grant Medical Foundation, Pune (India); Vaid, N. [Department of Otorhinolaryngology, K.E.M. Hospital, Pune (India); Rawat, S. [Department of Radiology and Imaging, Grant Medical Foundation, Pune (India); Ahuja, A.T. [Department of Diagnostic Radiology and Organ Imaging, The Chinese University of Hong Kong (Hong Kong)

2011-05-15

The reference standard for preoperative imaging in functional endoscopic sinus surgery (FESS) is multiplanar high-resolution computed tomography (HRCT). Surgeons require a precise preoperative anatomical road map, and hence it is essential for radiologists to be familiar with the normal three-dimensional sinonasal anatomy and the normal variants encountered in this region. Sagittal imaging has recently emerged as an important tool to visualize additional details in this critical anatomical region. Radiologists also need to report these examinations with special focus on the surgeon's expectations. Constant communication between the radiologist and the surgeon helps to resolve specific issues and improve the overall quality of reports. This results in better preoperative patient counselling and in predicting postoperative improvement in clinical status. This review provides a basic structured format for reporting pre-FESS CT, which can be tailored to meet individual requirements. The CT reporting format follows the order in which the sinonasal structures are approached during surgery.

Surgical stent for dental implant using cone beam CT images

International Nuclear Information System (INIS)

Choi, Hyung Soo; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan

2010-01-01

The purpose of this study is to develop a surgical stent for dental implant procedure that can be easily applied and affordable by using cone beam computerized tomography (CBCT). Aluminum, Teflon-PFA (perfluoroalkoxy), and acetal (polyoxymethylene plastic) were selected as materials for the surgical stent. Among these three materials, the appropriate material was chosen using the CBCT images. The surgical stent, which could be easily placed into an oral cavity, was designed with chosen material. CBCT images of the new surgical stent on mandible were obtained using Alphard-3030 dental CT system (Asahi Roentgen Co., Ltd., Kyoto, Japan). The point of insertion was prescribed on the surgical stent with the multiplanar reconstruction software of OnDemand3D (CyberMed Inc., Seoul, Korea). Guide holes were made at the point of insertion on the surgical stent using newly designed guide jig. CBCT scans was taken for the second time to verify the accuracy of the newly designed surgical stent. Teflon-PFA showed radiologically excellent image characteristics for the surgical stent. High accuracy and reproducibility of implantation were confirmed with the surgical stent. The newly designed surgical stent can lead to the accurate implantation and achieve the clinically predictable result.

Numerical methods in image processing for applications in jewellery industry

OpenAIRE

Petrla, Martin

2016-01-01

Presented thesis deals with a problem from the field of image processing for application in multiple scanning of jewelery stones. The aim is to develop a method for preprocessing and subsequent mathematical registration of images in order to increase the effectivity and reliability of the output quality control. For these purposes the thesis summerizes mathematical definition of digital image as well as theoretical base of image registration. It proposes a method adjusting every single image ...

New adaptive sampling method in particle image velocimetry

International Nuclear Information System (INIS)

Yu, Kaikai; Xu, Jinglei; Tang, Lan; Mo, Jianwei

2015-01-01

This study proposes a new adaptive method to enable the number of interrogation windows and their positions in a particle image velocimetry (PIV) image interrogation algorithm to become self-adapted according to the seeding density. The proposed method can relax the constraint of uniform sampling rate and uniform window size commonly adopted in the traditional PIV algorithm. In addition, the positions of the sampling points are redistributed on the basis of the spring force generated by the sampling points. The advantages include control of the number of interrogation windows according to the local seeding density and smoother distribution of sampling points. The reliability of the adaptive sampling method is illustrated by processing synthetic and experimental images. The synthetic example attests to the advantages of the sampling method. Compared with that of the uniform interrogation technique in the experimental application, the spatial resolution is locally enhanced when using the proposed sampling method. (technical design note)

FFT-enhanced IHS transform method for fusing high-resolution satellite images

Science.gov (United States)

Ling, Y.; Ehlers, M.; Usery, E.L.; Madden, M.

2007-01-01

Existing image fusion techniques such as the intensity-hue-saturation (IHS) transform and principal components analysis (PCA) methods may not be optimal for fusing the new generation commercial high-resolution satellite images such as Ikonos and QuickBird. One problem is color distortion in the fused image, which causes visual changes as well as spectral differences between the original and fused images. In this paper, a fast Fourier transform (FFT)-enhanced IHS method is developed for fusing new generation high-resolution satellite images. This method combines a standard IHS transform with FFT filtering of both the panchromatic image and the intensity component of the original multispectral image. Ikonos and QuickBird data are used to assess the FFT-enhanced IHS transform method. Experimental results indicate that the FFT-enhanced IHS transform method may improve upon the standard IHS transform and the PCA methods in preserving spectral and spatial information. ?? 2006 International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS).

Magnetic resonance imaging of the fetal brain.

Science.gov (United States)

Tee, L Mf; Kan, E Yl; Cheung, J Cy; Leung, W C

2016-06-01

This review covers the recent literature on fetal brain magnetic resonance imaging, with emphasis on techniques, advances, common indications, and safety. We conducted a search of MEDLINE for articles published after 2010. The search terms used were "(fetal OR foetal OR fetus OR foetus) AND (MR OR MRI OR [magnetic resonance]) AND (brain OR cerebral)". Consensus statements from major authorities were also included. As a result, 44 relevant articles were included and formed the basis of this review. One major challenge is fetal motion that is largely overcome by ultra-fast sequences. Currently, single-shot fast spin-echo T2-weighted imaging remains the mainstay for motion resistance and anatomical delineation. Recently, a snap-shot inversion recovery sequence has enabled robust T1-weighted images to be obtained, which is previously a challenge for standard gradient-echo acquisitions. Fetal diffusion-weighted imaging, diffusion tensor imaging, and magnetic resonance spectroscopy are also being developed. With multiplanar capabilities, superior contrast resolution and field of view, magnetic resonance imaging does not have the limitations of sonography, and can provide additional important information. Common indications include ventriculomegaly, callosum and posterior fossa abnormalities, and twin complications. There are safety concerns about magnetic resonance-induced heating and acoustic damage but current literature showed no conclusive evidence of deleterious fetal effects. The American College of Radiology guideline states that pregnant patients can be accepted to undergo magnetic resonance imaging at any stage of pregnancy if risk-benefit ratio to patients warrants that the study be performed. Magnetic resonance imaging of the fetal brain is a safe and powerful adjunct to sonography in prenatal diagnosis. It can provide additional information that aids clinical management, prognostication, and counselling.

A novel method for detecting light source for digital images forensic

Science.gov (United States)

Roy, A. K.; Mitra, S. K.; Agrawal, R.

2011-06-01

Manipulation in image has been in practice since centuries. These manipulated images are intended to alter facts — facts of ethics, morality, politics, sex, celebrity or chaos. Image forensic science is used to detect these manipulations in a digital image. There are several standard ways to analyze an image for manipulation. Each one has some limitation. Also very rarely any method tried to capitalize on the way image was taken by the camera. We propose a new method that is based on light and its shade as light and shade are the fundamental input resources that may carry all the information of the image. The proposed method measures the direction of light source and uses the light based technique for identification of any intentional partial manipulation in the said digital image. The method is tested for known manipulated images to correctly identify the light sources. The light source of an image is measured in terms of angle. The experimental results show the robustness of the methodology.

Spectral analysis of mammographic images using a multitaper method

International Nuclear Information System (INIS)

Wu Gang; Mainprize, James G.; Yaffe, Martin J.

2012-01-01

Purpose: Power spectral analysis in radiographic images is conventionally performed using a windowed overlapping averaging periodogram. This study describes an alternative approach using a multitaper technique and compares its performance with that of the standard method. This tool will be valuable in power spectrum estimation of images, whose content deviates significantly from uniform white noise. The performance of the multitaper approach will be evaluated in terms of spectral stability, variance reduction, bias, and frequency precision. The ultimate goal is the development of a useful tool for image quality assurance. Methods: A multitaper approach uses successive data windows of increasing order. This mitigates spectral leakage allowing one to calculate a reduced-variance power spectrum. The multitaper approach will be compared with the conventional power spectrum method in several typical situations, including the noise power spectra (NPS) measurements of simulated projection images of a uniform phantom, NPS measurement of real detector images of a uniform phantom for two clinical digital mammography systems, and the estimation of the anatomic noise in mammographic images (simulated images and clinical mammograms). Results: Examination of spectrum variance versus frequency resolution and bias indicates that the multitaper approach is superior to the conventional single taper methods in the prevention of spectrum leakage and variance reduction. More than four times finer frequency precision can be achieved with equivalent or less variance and bias. Conclusions: Without any shortening of the image data length, the bias is smaller and the frequency resolution is higher with the multitaper method, and the need to compromise in the choice of regions of interest size to balance between the reduction of variance and the loss of frequency resolution is largely eliminated.

A SAR IMAGE REGISTRATION METHOD BASED ON SIFT ALGORITHM

Directory of Open Access Journals (Sweden)

W. Lu

2017-09-01

Full Text Available In order to improve the stability and rapidity of synthetic aperture radar (SAR images matching, an effective method was presented. Firstly, the adaptive smoothing filtering was employed for image denoising in image processing based on Wallis filtering to avoid the follow-up noise is amplified. Secondly, feature points were extracted by a simplified SIFT algorithm. Finally, the exact matching of the images was achieved with these points. Compared with the existing methods, it not only maintains the richness of features, but a-lso reduces the noise of the image. The simulation results show that the proposed algorithm can achieve better matching effect.

Evaluation of the marsh deer stifle joint by imaging studies and gross anatomy.

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Shigue, D A; Rahal, S C; Schimming, B C; Santos, R R; Vulcano, L C; Linardi, J L; Teixeira, C R

2015-12-01

This study aimed to evaluate the stifle joint of marsh deer using imaging studies and in comparison with gross anatomy. Ten hindlimbs from 5 marsh deer (Blastocerus dichotomus) were used. Radiography, computed tomography (CT) and magnetic resonance imaging (MRI) were performed in each stifle joint. Two hindlimbs were dissected to describe stifle gross anatomy. The other limbs were sectioned in sagittal, dorsal or transverse planes. In the craniocaudal radiographic view, the lateral femoral condyle was broader than the medial femoral condyle. The femoral trochlea was asymmetrical. Subsequent multiplanar reconstruction revealed in the cranial view that the external surface of the patella was roughened, the medial trochlea ridge was larger than the lateral one, and the extensor fossa at the lateral condyle was next to the lateral ridge. The popliteal fossa was better visualized via the lateral view. Sagittal MRI images identified lateral and medial menisci, caudolateral and craniomedial bundles of cranial cruciate ligament, caudal cruciate ligament, patellar ligament and common extensor tendon. In conclusion, the marsh deer stifle presents some anatomical characteristics of the ovine stifle joint. © 2014 Blackwell Verlag GmbH.

Feasibility study on X-ray source with pinhole imaging method

International Nuclear Information System (INIS)

Qiu Rui; Li Junli

2007-01-01

In order to verify the feasibility of study on X-ray source with pinhole imaging method, and optimize the design of X-ray pinhole imaging system, an X-ray pinhole imaging equipment was set up. The change of image due to the change of the position and intensity of X-ray source was estimated with mathematical method and validated with experiment. The results show that the change of the spot position and gray of the spot is linearly related with the change of the position and intensity of X-ray source, so it is feasible to study X-ray source with pinhole imaging method in this application. The results provide some references for the design of X-ray pinhole imaging system. (authors)

New diffusion imaging method with a single acquisition sequence

International Nuclear Information System (INIS)

Melki, Ph.S.; Bittoun, J.; Lefevre, J.E.

1987-01-01

The apparent diffusion coefficient (ADC) is related to the molecular diffusion coefficient and to physiologic information: microcirculation in the capillary network, incoherent slow flow, and restricted diffusion. The authors present a new MR imaging sequence that yields computed ADC images in only one acquisition of 9-minutes with a 1.5-T imager (GE Signa). Compared to the previous method, this sequence is at least two times faster and thus can be used as a routine examination to supplement T1-, T2-, and density-weighted images. The method was assessed by measurement of the molecular diffusion in liquids, and the first clinical images obtained in neurologic diseases demonstrate its efficiency for clinical investigation. The possibility of separately imaging diffusion and perfusion is supported by an algorithm

Definition imaging of an orebody with the radio imaging method (RIM)

International Nuclear Information System (INIS)

Stolarczyk, L.G.

1992-01-01

Waste rock dilution is an economic concern in the planning and design of mining methods for mineralized ore zones. Diamond core drilling and mineralogical examination of core are routinely used to determine the general shape of the ore body. Drilling on closer centers enhances the definition of the mineralization and oregrade across the orebody. In a practical sense, drilling time and cost limit definition. Crosshole scanning between drillholes with the radio imaging method (RIM) has been used to map changes in mineralization in the rock mass. The magnitude and phase of the RIM radio wave depend on the electrical conductivity of the rock mass. The conductivity strongly depends on the percent mineralization. Since the attenuation rate and phase constants of the radio wave are proportional to the one half power of conductivity, the measured crosshole radio wave data can be processed in a tomography algorithm to reconstruct images (map the change in conductivity (mineralization)). The tomography image enhances definition in the orebody while reducing the number of drillholes. This paper compares reconstructed images of the radio wave propagation constants to percent mineralization in the ore body

A simple method for detecting tumor in T2-weighted MRI brain images. An image-based analysis

International Nuclear Information System (INIS)

Lau, Phooi-Yee; Ozawa, Shinji

2006-01-01

The objective of this paper is to present a decision support system which uses a computer-based procedure to detect tumor blocks or lesions in digitized medical images. The authors developed a simple method with a low computation effort to detect tumors on T2-weighted Magnetic Resonance Imaging (MRI) brain images, focusing on the connection between the spatial pixel value and tumor properties from four different perspectives: cases having minuscule differences between two images using a fixed block-based method, tumor shape and size using the edge and binary images, tumor properties based on texture values using spatial pixel intensity distribution controlled by a global discriminate value, and the occurrence of content-specific tumor pixel for threshold images. Measurements of the following medical datasets were performed: different time interval images, and different brain disease images on single and multiple slice images. Experimental results have revealed that our proposed technique incurred an overall error smaller than those in other proposed methods. In particular, the proposed method allowed decrements of false alarm and missed alarm errors, which demonstrate the effectiveness of our proposed technique. In this paper, we also present a prototype system, known as PCB, to evaluate the performance of the proposed methods by actual experiments, comparing the detection accuracy and system performance. (author)

An Image Encryption Method Based on Bit Plane Hiding Technology

Institute of Scientific and Technical Information of China (English)

LIU Bin; LI Zhitang; TU Hao

2006-01-01

A novel image hiding method based on the correlation analysis of bit plane is described in this paper. Firstly, based on the correlation analysis, different bit plane of a secret image is hided in different bit plane of several different open images. And then a new hiding image is acquired by a nesting "Exclusive-OR" operation on those images obtained from the first step. At last, by employing image fusion technique, the final hiding result is achieved. The experimental result shows that the method proposed in this paper is effective.

An enhanced narrow-band imaging method for the microvessel detection

Science.gov (United States)

Yu, Feng; Song, Enmin; Liu, Hong; Wan, Youming; Zhu, Jun; Hung, Chih-Cheng

2018-02-01

A medical endoscope system combined with the narrow-band imaging (NBI), has been shown to be a superior diagnostic tool for early cancer detection. The NBI can reveal the morphologic changes of microvessels in the superficial cancer. In order to improve the conspicuousness of microvessel texture, we propose an enhanced NBI method to improve the conspicuousness of endoscopic images. To obtain the more conspicuous narrow-band images, we use the edge operator to extract the edge information of the narrow-band blue and green images, and give a weight to the extracted edges. Then, the weighted edges are fused with the narrow-band blue and green images. Finally, the displayed endoscopic images are reconstructed with the enhanced narrow-band images. In addition, we evaluate the performance of enhanced narrow-band images with different edge operators. Experimental results indicate that the Sobel and Canny operators achieve the best performance of all. Compared with traditional NBI method of Olympus company, our proposed method has more conspicuous texture of microvessel.

Mathematical methods in time series analysis and digital image processing

CERN Document Server

Kurths, J; Maass, P; Timmer, J

2008-01-01

The aim of this volume is to bring together research directions in theoretical signal and imaging processing developed rather independently in electrical engineering, theoretical physics, mathematics and the computer sciences. In particular, mathematically justified algorithms and methods, the mathematical analysis of these algorithms, and methods as well as the investigation of connections between methods from time series analysis and image processing are reviewed. An interdisciplinary comparison of these methods, drawing upon common sets of test problems from medicine and geophysical/enviromental sciences, is also addressed. This volume coherently summarizes work carried out in the field of theoretical signal and image processing. It focuses on non-linear and non-parametric models for time series as well as on adaptive methods in image processing.

Active learning methods for interactive image retrieval.

Science.gov (United States)

Gosselin, Philippe Henri; Cord, Matthieu

2008-07-01

Active learning methods have been considered with increased interest in the statistical learning community. Initially developed within a classification framework, a lot of extensions are now being proposed to handle multimedia applications. This paper provides algorithms within a statistical framework to extend active learning for online content-based image retrieval (CBIR). The classification framework is presented with experiments to compare several powerful classification techniques in this information retrieval context. Focusing on interactive methods, active learning strategy is then described. The limitations of this approach for CBIR are emphasized before presenting our new active selection process RETIN. First, as any active method is sensitive to the boundary estimation between classes, the RETIN strategy carries out a boundary correction to make the retrieval process more robust. Second, the criterion of generalization error to optimize the active learning selection is modified to better represent the CBIR objective of database ranking. Third, a batch processing of images is proposed. Our strategy leads to a fast and efficient active learning scheme to retrieve sets of online images (query concept). Experiments on large databases show that the RETIN method performs well in comparison to several other active strategies.

Reconstruction of CT images by the Bayes- back projection method

CERN Document Server

Haruyama, M; Takase, M; Tobita, H

2002-01-01

In the course of research on quantitative assay of non-destructive measurement of radioactive waste, the have developed a unique program based on the Bayesian theory for reconstruction of transmission computed tomography (TCT) image. The reconstruction of cross-section images in the CT technology usually employs the Filtered Back Projection method. The new imaging reconstruction program reported here is based on the Bayesian Back Projection method, and it has a function of iterative improvement images by every step of measurement. Namely, this method has the capability of prompt display of a cross-section image corresponding to each angled projection data from every measurement. Hence, it is possible to observe an improved cross-section view by reflecting each projection data in almost real time. From the basic theory of Baysian Back Projection method, it can be not only applied to CT types of 1st, 2nd, and 3rd generation. This reported deals with a reconstruction program of cross-section images in the CT of ...

Human body region enhancement method based on Kinect infrared imaging

Science.gov (United States)

Yang, Lei; Fan, Yubo; Song, Xiaowei; Cai, Wenjing

2016-10-01

To effectively improve the low contrast of human body region in the infrared images, a combing method of several enhancement methods is utilized to enhance the human body region. Firstly, for the infrared images acquired by Kinect, in order to improve the overall contrast of the infrared images, an Optimal Contrast-Tone Mapping (OCTM) method with multi-iterations is applied to balance the contrast of low-luminosity infrared images. Secondly, to enhance the human body region better, a Level Set algorithm is employed to improve the contour edges of human body region. Finally, to further improve the human body region in infrared images, Laplacian Pyramid decomposition is adopted to enhance the contour-improved human body region. Meanwhile, the background area without human body region is processed by bilateral filtering to improve the overall effect. With theoretical analysis and experimental verification, the results show that the proposed method could effectively enhance the human body region of such infrared images.

Quantitative Nuclear Medicine Imaging: Concepts, Requirements and Methods

Energy Technology Data Exchange (ETDEWEB)

NONE

2014-01-15

The absolute quantification of radionuclide distribution has been a goal since the early days of nuclear medicine. Nevertheless, the apparent complexity and sometimes limited accuracy of these methods have prevented them from being widely used in important applications such as targeted radionuclide therapy or kinetic analysis. The intricacy of the effects degrading nuclear medicine images and the lack of availability of adequate methods to compensate for these effects have frequently been seen as insurmountable obstacles in the use of quantitative nuclear medicine in clinical institutions. In the last few decades, several research groups have consistently devoted their efforts to the filling of these gaps. As a result, many efficient methods are now available that make quantification a clinical reality, provided appropriate compensation tools are used. Despite these efforts, many clinical institutions still lack the knowledge and tools to adequately measure and estimate the accumulated activities in the human body, thereby using potentially outdated protocols and procedures. The purpose of the present publication is to review the current state of the art of image quantification and to provide medical physicists and other related professionals facing quantification tasks with a solid background of tools and methods. It describes and analyses the physical effects that degrade image quality and affect the accuracy of quantification, and describes methods to compensate for them in planar, single photon emission computed tomography (SPECT) and positron emission tomography (PET) images. The fast paced development of the computational infrastructure, both hardware and software, has made drastic changes in the ways image quantification is now performed. The measuring equipment has evolved from the simple blind probes to planar and three dimensional imaging, supported by SPECT, PET and hybrid equipment. Methods of iterative reconstruction have been developed to allow for

Box-Counting Method of 2D Neuronal Image: Method Modification and Quantitative Analysis Demonstrated on Images from the Monkey and Human Brain

Directory of Open Access Journals (Sweden)

Nemanja Rajković

2017-01-01

Full Text Available This study calls attention to the difference between traditional box-counting method and its modification. The appropriate scaling factor, influence on image size and resolution, and image rotation, as well as different image presentation, are showed on the sample of asymmetrical neurons from the monkey dentate nucleus. The standard BC method and its modification were evaluated on the sample of 2D neuronal images from the human neostriatum. In addition, three box dimensions (which estimate the space-filling property, the shape, complexity, and the irregularity of dendritic tree were used to evaluate differences in the morphology of type III aspiny neurons between two parts of the neostriatum.

Box-Counting Method of 2D Neuronal Image: Method Modification and Quantitative Analysis Demonstrated on Images from the Monkey and Human Brain.

Science.gov (United States)

Rajković, Nemanja; Krstonošić, Bojana; Milošević, Nebojša

2017-01-01

This study calls attention to the difference between traditional box-counting method and its modification. The appropriate scaling factor, influence on image size and resolution, and image rotation, as well as different image presentation, are showed on the sample of asymmetrical neurons from the monkey dentate nucleus. The standard BC method and its modification were evaluated on the sample of 2D neuronal images from the human neostriatum. In addition, three box dimensions (which estimate the space-filling property, the shape, complexity, and the irregularity of dendritic tree) were used to evaluate differences in the morphology of type III aspiny neurons between two parts of the neostriatum.

A Novel Image Tag Completion Method Based on Convolutional Neural Transformation

KAUST Repository

Geng, Yanyan; Zhang, Guohui; Li, Weizhi; Gu, Yi; Liang, Ru-Ze; Liang, Gaoyuan; Wang, Jingbin; Wu, Yanbin; Patil, Nitin; Wang, Jing-Yan

2017-01-01

In the problems of image retrieval and annotation, complete textual tag lists of images play critical roles. However, in real-world applications, the image tags are usually incomplete, thus it is important to learn the complete tags for images. In this paper, we study the problem of image tag complete and proposed a novel method for this problem based on a popular image representation method, convolutional neural network (CNN). The method estimates the complete tags from the convolutional filtering outputs of images based on a linear predictor. The CNN parameters, linear predictor, and the complete tags are learned jointly by our method. We build a minimization problem to encourage the consistency between the complete tags and the available incomplete tags, reduce the estimation error, and reduce the model complexity. An iterative algorithm is developed to solve the minimization problem. Experiments over benchmark image data sets show its effectiveness.

A Novel Image Tag Completion Method Based on Convolutional Neural Transformation

KAUST Repository

Geng, Yanyan

2017-10-24

In the problems of image retrieval and annotation, complete textual tag lists of images play critical roles. However, in real-world applications, the image tags are usually incomplete, thus it is important to learn the complete tags for images. In this paper, we study the problem of image tag complete and proposed a novel method for this problem based on a popular image representation method, convolutional neural network (CNN). The method estimates the complete tags from the convolutional filtering outputs of images based on a linear predictor. The CNN parameters, linear predictor, and the complete tags are learned jointly by our method. We build a minimization problem to encourage the consistency between the complete tags and the available incomplete tags, reduce the estimation error, and reduce the model complexity. An iterative algorithm is developed to solve the minimization problem. Experiments over benchmark image data sets show its effectiveness.

Some selected quantitative methods of thermal image analysis in Matlab.

Science.gov (United States)