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At least 577 records · Page 32Linked to original sources

Texture analysis of foot sole soft tissue images in diabetic neuropathy using wavelet transform.

The paper presents a new method of characterisation of texture changes in foot sole soft tissue ultrasound (US) images, as observed to occur in diabetic subjects, using wavelet transforms. US images of the soft tissue subcutaneous layer were taken with a 7.5 MHz linear transducer probe placed parallel to the skin surface. The foot sole hardness was characterised by Shore level. A 2D discrete wavelet transform was performed on the US images to extract features that encode the internal state of the foot sole soft tissue. The global energy feature computed at the output of each wavelet channel was found to achieve excellent delineation between the normal and the diabetic groups. An important finding was a strong correlation, in the order of 0.84 and above, between the feature values that reflect changes in the internal arrangement of the tissue, and the externally measurable hardening of the skin, characterised by the Shore levels, with the latter known to be high for diabetics. A comparison drawn between diabetic ulcer and non-ulcer groups established a change in the order of 122-311% in the textural parameter, as influenced by a corresponding 66.7-200% change in the respective Shore values. Thus US examination of foot sole soft tissue and its texture analysis may serve as sources of valuable information regarding the internal changes taking place with progressive hardening of the soft tissue and thereby help the clinician in taking appropriate preventive measures.

Adult↗

The effect of lossy discrete cosine transform compression on subtle bone fractures.

Extensive research efforts have been devoted to the feasibility of picture archiving and communication systems (PACS) in recent years. The advantages of PACS are numerous but mainly include reduced cost and improvement in the operational efficiency of a PACS-based radiology department. In digital radiography, images are viewed either in hard-copy or soft-copy format. Usually, these images are subsequently compressed and archived for future evaluation. There are various methods used in image compression. In this study, computed radiography images showing subtle pediatric bone fractures were compressed with the lossy method of image compression after they had been initially evaluated on workstation monitors. These studies were subsequently evaluated by observers, who were unaware of the interpretations of these images before compression, to determine if they could detect similar abnormalities. Our conclusion is that there is no difference in the interpretation of soft-copy computed radiographic images before or after lossy 10:1 compression in studies of subtle pediatric bone fractures. This is a US government work. There are no restrictions on its use.

Analysis of Variance↗

Osteosarcoma of the orbit associated with Paget disease.

Osteosarcoma is a common primary bone malignancy most often involving the long bones and occurring in the second decade of life. Orbital involvement in this disease process is rare and is usually due to extension of the tumor from an adjacent sinus cavity. Orbital osteosarcoma arising from preexisting Paget disease is exceedingly rare. We report the case of a 78-year-old female patient with Paget disease of the forehead who presented with rapidly increasing bilateral proptosis and visual loss for several months. Examination showed bilateral aphakia, decreased motility, proptosis with resistance to retropulsion, and tumorous infiltration of the eyelids and periorbital soft tissue. Fundus examination showed marked bilateral scleral indentation without overlying serous retinal detachment. A computed tomographic (CT) evaluation of the orbits demonstrated extensive soft tissue involvement of the paranasal sinuses, nasal cavity, periorbital soft tissue, and orbits, with compression of the optic nerve and globe bilaterally. Biopsy of the periorbital soft tissue demonstrated osteosarcoma. Radiation therapy failed to stem the progression of the disease process, and the patient died approximately 4 months later. Although osteosarcoma of the orbit associated with Paget disease is unusual, it should be considered in the differential diagnosis of older patients with a rapidly progressive orbital mass.

Aged↗

Soft tissue strain and facet face interaction in the lumbar intervertebral joint--Part I: Input data and computational technique.

A numerical simulation was devised to determine ligament strains, facet face interaction, and disk fiber strain in the lumbar intervertebral joint under load. This technique uses experimentally derived load deflection and morphologic data from lumbar cadaver specimens from which initial and displaced soft tissue attachment points can be calculated. This allows the strain data to be derived. The effect of disk bulge is also considered. The calculated strains of most ligaments except the facet capsular ligaments were found to be insensitive to anatomical measurement variability of +/- 1 mm.

Adolescent↗

[Development and applications of a computer aided complete denture design system].

OBJECTIVE: The purpose of this study was to develop a practical CAD/CAM system with knowledge databases for complete denture. METHODS: A three-dimensional coordinate measuring machine (3DCMM) was used to collect three-dimensional information of edentulous models and bite plates and the mathematics model of complete denture was established using B-Spline method. This system was established by seting eight functional models: the measuring model, the converting data model, the constructing curve-surface model, the producing base and the editing model, the arranging artificial and the editing model, the outputting income model, the imitating dynamic model and the managing model. RESULTS: (1) The soft and hard system of a computer aided complete denture design (CACDD) was established, including 3DCMM, 8 functional models and databases. (2) A CACDD system and the three-dimensional demonstration were completed. CONCLUSION: This system lay down the foundation for setting up the computer aided complete denture design/manufacturing system.

Computer-Aided Design↗

Diffuse soft tissue emphysema in anorexia nervosa: a case report.

OBJECTIVE: Anorexia nervosa (AN) is an eating disorder that occurs mainly among young females and its prevalence has increased in recent decades. METHODS: We reported a patient with AN with spontaneous diffuse soft tissue emphysema and bicytopenia, both of which are very rare complications of AN. Our patient, a 20-year-old woman, had lost 41.6% of her previous body weight within 9 months. Her body mass index was 10.8 and amenorrhea had persisted for 5 months. RESULTS: After admission, she was diagnosed with AN-restrictive subtype. She was noted to have crunching sounds in the neck and upper chest wall during hospitalization. A chest X-ray and chest computed tomography scan both revealed diffuse soft tissue emphysema including subcutaneous emphysema, pneumomediastinum, and pneumoretroperitoneum. DISCUSSION: Diffuse soft tissue emphysema improved gradually and completely resolved on the 21st day of hospitalization. This condition seems to be benign and only a short period of hospitalization is required.

Adult↗

Lipoblastomatosis in a newborn: case report.

A male newborn had a well-circumscribed, solid mass on the right anterior chest wall at birth. Computed tomography disclosed an infiltrating soft-tissue mass over the right 6th to 9th ribs near the costochondral junction. Surgical excision was done at the age of 5 days. Pathologic examination showed lipoblastomatosis.

Humans↗

[Experimental study of bone morphogenetic protein-2 in noncemented fixation of prosthesis].

OBJECTIVE: To study on the method of combining rhBMP(2) with porous-coated implants, and compared the histological and biomechanical results of 4 types of implants by being inserted into the femur of canine. METHODS: 4 types of implants which are porous-coated implants (PCA), PCA implants combined with BMP, PCA implants coated with hydroxyapatite and HA coated cylindrical implants had been inserted into the femur of 16 canines. After 4, 8, 12 and 24 weeks the femur of the canines with the implants were retrieved. Bone ingrowth and shear strength of the interface was studied and analysed by the means of X-ray, soft X-ray, fluorescence tag, non-decalcification bone ground section, computer-aided image analysis procedure and biomechanical test. RESULTS: X-ray, soft X-ray, fluorescence tag, non-decalcification bone ground section and computer-aided image analysis procedure was used in histological study, and it showed that bony ingrowth into interface more than the other groups, even the maturation of newly formed bone. Non-decalcification bone ground section observation and computer aided image analysis showed the results: the new bone formation ratio of BMP group was 26.58% +/- 4.56% at 4 weeks post-implantation, which was much higher than the other groups, and there was significant difference between BMP group and each of the other group statistically (P < 0.05). Results of biomechanical study using push-out test showed that shear strength of each group appeared to rise with time. Shear strength of BMP group reached a high level at 4 weeks which was 18.94 +/- 5.11Mpa and almost twice of the other group, and there was also statistical difference between BMP group and each of the other group (P < 0.05). And the new bone formation ratio and shear strength of BMP group at 8, 12, 24 weeks post-implantation was still higher than the other group, but there was no statistically difference. CONCLUSIONS: Porous-coated implants combined with rhBMP can enhance bone ingrowth at bone-implant interface especially at the early period post-implantation. Porous-coated implants combined with rhBMP(2) can not only shorten the time of new bone formation and bone ingrowth but also enhance shear strength of bone-implant interface.

Animal Experimentation↗

Retroperitoneal actinomycosis with intraperitoneal spread. Stellate pattern on CT.

We report a case of pathologically proved actinomycosis that presented unusual computed tomographic (CT) features: a soft-tissue retroperitoneal mass encasing the adjacent ureter resulting in hydronephrosis and spreading into the intraperitoneal space with a stellate pattern. The role of CT in monitoring the response to antibiotic treatment is also discussed.

Actinomycosis↗

Computed radiography in neonatal and pediatric intensive care units: a comparison of 2.5 K x 2 K soft-copy images vs digital hard-copy film.

OBJECTIVE: The goal of the study was to determine whether soft-copy images on high-resolution monitors (2.5 K x 2 K) are suitable for primary interpretation of images from pediatric and neonatal intensive care units. The hypotheses were that hard and soft images yield similar diagnostic information, and that both residents and faculty radiologists can use monitors effectively. Previous reports have produced conflicting results; the need for larger sample sizes has been emphasized. MATERIALS AND METHODS: One thousand one hundred and four images produced by computed radiography using the Kodak Ectascan Imagelink system were prospectively analyzed by two pediatric radiologists, one reading hard copy and the other soft copy of the same images. Bias was controlled by equal distribution of modalities between observers and by daily alternation of modality. Hard- and soft-copy observations of presence or absence of nine specific tubes and nine specific diagnostic findings were compared. Interobserver differences between pediatric radiologists and radiology residents were studied on additional images. The kappa statistic was used to evaluate the level of agreement for all observations. RESULTS: There was excellent agreement between hard and soft copy interpretation for each tube and diagnostic finding (kappa values 0.93-1.0) and excellent interobserver agreement between two pediatric radiologists (kappa values 0.84-1.0). The level of agreement between radiology residents and pediatric radiologist was excellent for the most objective findings. All results were statistically significant (p < 0.001). CONCLUSION: High resolution soft-copy images are suitable for primary interpretation in patients in pediatric and neonatal intensive care units.

Child↗

Use of texture parameters in the classification of soft tissue tumors.

Soft tissue tumors are a challenging group of tumors that presents wide morphologic variety. For pathologists, the degree of cellular differentiation, the cellular and nuclear polymorphism and the mitotic rate are major criteria for diagnosis. In image analysis, the architectural organization of such tumors shows local variations that can be understood as texture variations. This study introduced a method of measuring the architectural organization of soft tissue tumors from texture analysis of tissue sections at low magnification. We studied 40 cases of soft tissue tumors classified by pathologists into three groups according to their histologic patterns. Twelve texture parameters were calculated on subimages of 128 x 128 pixels. Our results show that tissue architecture evaluated by texture analysis provides good discrimination of myxoid, spindle cell and round cell tumors.

Cell Differentiation↗

Mixed and Penalty Finite Element Models for the Nonlinear Behavior of Biphasic Soft Tissues in Finite Deformation: Part I - Alternate Formulations.

This paper addresses finite element-based computational models for the three-dimensional, (3-D) nonlinear analysis of soft hydrated tissues, such as the articular cartilage in diarthrodial joints, under physiologically relevant loading conditions. A biphasic continuum description is used to represent the soft tissue as a two-phase mixture of incompressible, inviscid fluid and a hyperelastic solid. Alternate mixed-penalty and velocity-pressure finite element formulations are used to solve the nonlinear biphasic governing equations, including the effects of a strain-dependent permeability and a hyperelastic solid phase under finite deformation. The resulting first-order nonlinear system of equations is discretized in time using an implicit finite difference scheme, and solved using the Newton-Raphson method. Using a discrete divergence operator, an equivalence is shown between the mixed-penalty method and a penalty method previously derived by Suh et al. [1]. In Part II [2], the mixed-penalty and velocity-pressure formulations are used to develop two-dimensional (2-D) quadrilateral and triangular elements and 3-D hexahedral and tetrahedral elements. Numerical examples, including those representative of soft tissue material testing and simple human joints, are used to validate the formulations and to illustrate their applications. A focus of this work is the comparison of alternate formulations for nonlinear problems. While it is demonstrated that both formulations produce a range of converging elements, the velocity-pressure formulation is found to be more efficient computationally.

Journal Article↗

[Magnetic resonance computerized tomography in the diagnosis of soft tissue neoplasms].

Sixty-three patients with malignant and benign tumors of soft tissues were examined making use of magnetic resonance computer-aided tomography (MRT). This method was found effective in the diagnosis of soft tissue tumors, permitting the detection of tumor connection with the adjacent structures. In some cases MRT helped differentiate between malignant and benign soft tissue tumor growth, e.g. liposarcoma, malignant fibrous histiocytoma, lipoma, desmoid, hematoma. MRT may be effectively used in the diagnosis of soft tissue formations.

Adult↗

Harmonic analysis of facial profiles: a 10-year evaluation.

A 10-year longitudinal evaluation was performed of the morphology of soft tissue facial profiles of 14 healthy adults (8 female and 6 male; mean age at the second evaluation, 34 years). Standardized left-side photographs were taken of each subject, and facial profiles were traced between trichion and cervical point. The line joining the 2 landmarks was set as the baseline, and each outline was automatically digitized and mathematically reconstructed by a 20-harmonic elliptic Fourier series expansion. Shape modifications were quantified by calculating the morphologic distance between the Fourier reconstruction of each facial profile in the 2 examinations. The area enclosed in each facial outline was automatically computed, and the difference between the soft tissue areas obtained in the 2 examinations was calculated. On average, significant longitudinal differences were found in both men and women for shape differences (P < 0.05), while size variations were significant only in men. While the 10-year increase in size was significantly (P < 0.01) larger in men than in women, no sex-related differences were found for shape modifications. Between the third and the fourth decades of life, both men and women experience some modifications in their facial soft tissues. While shape changes in both sexes, size changes are particularly evident in men and less manifest in women, who show greater variability in the amount of change that takes place.

Adult↗

[Gas gangrene or inflammation of the neck--diagnostic difficulties].

The authors describe a patient with an extensive inflammation of the neck soft tissues as a complication of the peritonsillar abscess. Follow-up computed tomography revealed gasi-form follicles in the inflammed neck soft tissues, suggesting gas gangrene. We report disseminate ways of the inflammation process on the financial tonsil, reasons of the gangrene also the infections of soft tissues caused by anaerobic bacteries--Clostridium. CT--examination in inflammatory tumors of the neck is valuable, permits to exclude expansion process, but it cannot give unequivocal answer to differentiate gas gangrene and phlegmon.

Bacterial Infections↗

[A case report of cervical disc hernia presenting fecal incontinence evoked by walking; spinal intermittent rectal dysfunction].

Intermittent clinical manifestations, the representative one of which is claudication, can be classified into two types; neurogenic and vasculogenic. Although cauda equina lesions are well known as a neurogenic cause, spinal disorders, especially cervical or thoracic cord lesions, have been paid more attention to by several authors recently. We encountered a 42-year-old man with cervical soft disc hernia and ossification of longitudinal ligament, who showed intermittent rectal dysfunction evoked by walking. This peculiar clinical manifestation successfully disappeared after surgical decompression of the spinal cord. Such an interesting case has not been reported in the world literature. The patient was admitted because of numbness in both hands. Neurological examinations on admission showed neither motor weakness nor abnormally increased tendon reflex. Hypesthesia and hypalgesia were noticed below the Th4 dermatome on both sides. Adding to those symptoms, he complained of fecal incontinence evoked by walking 100 meters. This rectal dysfunction became gradually worse. At last he showed fecal incontinence after walking only 10 meters. This was ten days after his admission. Myelogram and computed tomographic scan revealed a cervical soft disc hernia at the C5/6 level and findings of OPLL at the C5 and C6 level. Anterior cervical approach for OPLL and soft disc was used for bone graft insertion from the C4 to the C7 vertebral body. The rectal dysfunction completely disappeared after the operation. The possible mechanisms of intermittent rectal dysfunction evoked by walking were discussed.

Adult↗

Feasibility study of x-ray diffraction computed tomography for medical imaging.

A feasibility study of soft-tissue imaging based on x-ray wide-angle diffraction contrast has been performed at the medical beamline of the European Synchrotron Radiation Facility (ESRF). The technique employs computed-tomography algorithms to reconstruct from one data set the spatial distribution of several tissues differentiated by their diffraction properties. Radial diffraction profiles are measured in parallel projections from the sample and decomposed into material-selective weighting factors, which form the sinograms for the reconstructions. Attenuation effects--inherent in imaging techniques using scattered radiation--are efficiently corrected for by a ray-tracing method applied to the corresponding absorption image. Images of 7 cm diameter samples composed of fat, bone and muscle were generated at 60 and 80 keV x-ray energy. The highest surface-absorbed dose was 24 mGy, but substantial contrast could still be obtained at 7 mGy, indicating potential applicability in medical imaging. The dominant noise contribution in the images stems from the detection system, pointing to a possible decrease in the surface-absorbed dose for an optimized system of more than a factor of 2.

Adipose Tissue↗