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PubMed1997

[The development and application of computer assisted photogrammetric-system of facial soft tissue running under multiple facilities for taking image].

The photogrammetric-system was developed by using multimedia computer, colour television camera, SE100 video blaster, Newsketch 1212 HR digitizer and by using Visual Basic language. It ran under Windows 3.1 and Windows 95. The features of this system: 1. It had three kinds of functions: photogrammetric function for frontal and profile facial soft tissue, function for managing file and function for forming dynamic data base. 2. It ran under different facilities for taking image (television camera with video blaster, digitizer, scanner) speedily and specificly, and had very friendly interface, and was of multimedia. The application of this system: 1. assisting diagnosing, making plan for treatment and observing results of treatment in clinic of orthodontics, orthopedics and facial plastics, 2. assisting analysing the features of facial soft tissue about certain people, 3. assisting the multimedia teaching.

Adolescent↗
PubMed1998

[Osteomyelitis--imaging methods and their value].

Various imaging modalities are used in diagnosis of acute and chronic infectious endogenous osteomyelitis and exogenous ostitis. The pathophysiological changes of osteomyelitis/ostitis in the bone and surrounding soft tissue are known. Findings in plain film radiography show these changes only in relatively advanced stages of disease. Hence, plain film radiographs are useful as a basic imaging modality by excluding other differentials and as a follow-up modality under therapy. Ultrasound-using advanced technology--offers diagnostic help in acute osteomyelitis, especially in infants. The various techniques of nuclear medicine show much higher sensitivity for detecting osteomyelitis than plain film radiography, but do not permit good separation for bone involvement and infectious changes in the surrounding soft tissue. While computed tomography offers the ability to display bone and soft tissue separately, it has been widely replaced by magnetic resonance imaging using fat-suppressed sequences and paramagnetic contrast media which show the spread of the infectious changes with higher sensitivity and accuracy.

Adolescent↗
PubMed1992

[A comparison between echography and computed tomography in assessing neoplastic recurrences in superficial soft tissues].

Thirty-seven superficial soft-tissue recurrences were evaluated with ultrasonography (US) and computed tomography (CT) to assess the correct diagnostic approach. US and CT examinations were performed at the same time. High-frequency US probes and a third-generation CT scanner were employed; all the lesions underwent also histology or cytology. US correctly identified as recurrences or fibrous tissue all the 37 lesions, whereas CT diagnosed 30 lesions only. Seven of the 14 recurrences < 2 cm diameter were not demonstrated. In conclusion, US provides more reliable information than CT relative to small lesions, which suggests that US must be performed just after therapy. Nevertheless, when bone involvement is suspected, CT is required and its use is also suggested to monitor distant metastases.

Biopsy, Needle↗
PubMed2002

Cost-effectiveness of staging computed tomography of the chest in patients with T2 soft tissue sarcomas.

BACKGROUND: Published practice guidelines recommend routine chest computed tomography (CT) scanning as part of the staging evaluation for patients with T2 soft tissue sarcomas (STS), although there is no direct evidence to support this practice. The objective of this study was to determine the yield and cost-effectiveness of routine versus selective chest CT scanning for the staging of patients with T2 STS and to identify any subgroups for whom a more selective approach to chest CT scanning could be considered. METHODS: Six hundred consecutive patients with primary, nonthoracic, T2 (> 5 cm) STS underwent both chest X-ray (CXR) and chest CT scanning to evaluate the presence of pulmonary metastatic disease (M1). The authors constructed a decision tree that modeled the outcomes of diagnostic testing for two hypothetical diagnostic strategies: 1) routine chest CT (rCT) or 2) CXR and selective chest CT (sCT). The yield and cost of each strategy were determined; the incremental cost-effectiveness ratio (ICER) was calculated as the cost per additional patient with pulmonary metastases identified by rCT versus sCT. RESULTS: The yield of rCT was higher than that of sCT (M1 disease identified in 19.2% vs. 16.0% of patients, respectively), but rCT was more costly ($1301 vs. $418 per patient, respectively). The ICER of rCT compared with sCT was $27,594 per patient identified with pulmonary metastasis. The expected yields, costs, and ICERs of the diagnostic strategies varied across patient subgroups based on grade, anatomic site, and tumor size. CONCLUSIONS: For patients with T2 STS, rCT was most cost-effective in patients with high-grade lesions or extremity lesions. The findings of this study do not support the routine use of chest CT scanning in all patients with T2 STS.

Adolescent↗
PubMed1979

Computed tomography evaluation of fatty tumors of the somatic soft tissues: clinical utility and radiologic-pathologic correlation.

The role of computed tomography (CT) in the evaluation of fatty tumors of the somatic soft tissues was investigated. Six surgically proven cases of fatty tumors were studied preoperatively by CT and standard radiographic means--conventional radiographs, xeroradiography, and angiography. Our case material included a simple lipoma, two infiltrative lipomas, an angiolipoma, and two liposarcomas. The radiologic-pathologic correlation was evaluated with respect to the various imaging modalities. The unique tissue characteristics of fatty tumors makes them particularly adaptable to CT scanning. In addition to its ability to define accurately tissue densities, the facility of CT in depicting depth, size, and extent of the lesion in the axial plane was found to be most useful in the preoperative evaluation of our case material.

Adipose Tissue↗
PubMed2002

Use of computed tomographic densitometry to quantify contrast enhancement of compressive soft tissues in the canine lumbosacral vertebral canal.

OBJECTIVES: To evaluate computed tomography (CT) densitometry as a technique for quantifying contrast enhancement of compressive soft tissues in the canine lumbosacral vertebral canal and to determine whether the degree of contrast enhancement can be used to help predict tissue type or histopathologic characteristics. ANIMALS: 29 large breed dogs with lumbosacral stenosis. PROCEDURE: Contrast-enhanced CT of L5-S3 was performed by use of a previously described protocol. At each disk level, CT densities of a water-filled syringe, epaxial muscles, and 4 vertebral canal locations were measured. Mean tissue enhancement was calculated by vertebral canal location, using water-filled syringe enhancement as a correction factor. Corrected CT enhancement was compared with tissue type, degree of tissue inflammation, and degree of tissue activity. RESULTS: Intravenous contrast administration of contrast medium significantly increased CT densities of water-filled syringes and epaxial muscles. Corrected CT enhancement of vertebral canal soft tissues at stenotic sites was greater than at nonstenotic sites. There was no association between enhancement and tissue type for any vertebral canal location. There was no correlation between enhancement and degree of tissue inflammation. There was a correlation between enhancement and tissue activity in the dorsal vertebral canal only. CONCLUSIONS AND CLINICAL RELEVANCE: A water-filled syringe is a useful calibration tool for CT density measurements. The degree of tissue contrast enhancement, measured by CT densitometry, can be helpful for predicting the location of compressive soft tissues in dogs with lumbosacral stenosis. However, it is of limited value for predicting compressive soft-tissue types or histopathologic characteristics.

Animals↗
PubMed2003

Carbon dioxide reactivity of computed tomography functional parameters in rabbit VX2 soft tissue tumour.

Tumour blood flow is one of the important factors limiting the efficacy of radiation therapy (hypoxic radioresistance), chemotherapy (drug delivery) and thermal therapy (heat dissipation) in treating cancer. The modification of tumour blood flow has been an area of intense investigation. In the current study, the arterial carbon dioxide tension (PaCO2) was changed in order to investigate the tumour vascular response to carbon dioxide. Functional maps of blood flow, blood volume and mean transit time were generated at four PaCO2 levels in VX2 tumour in the rabbit thigh and normal soft tissue. The PaCO2 levels investigated were normocapnia (PaCO2 = 40.9 +/- 1.2 mmHg), hypocapnia (27.2 +/- 2.3 and 33.5 +/- 2.3 mmHg) and hypercapnia (54.9 +/- 4.4 mmHg). The carbon dioxide reactivity of the global tumour blood flow and mean transit time showed significant differences between normocapnia and the two levels of hypocapnia, but not between normocapnia and hypercapnia. The average fractional change of blood flow from normocapnia for the two levels of hypocapnia was -0.41 +/- 0.06 and -0.29 +/- 0.08, respectively (P < 0.05). In the case of mean transit time the fractional change was +0.39 +/- 0.30 and +0.23 +/- 0.24, respectively (P < 0.05). The fractional change of blood volume from normocapnia, however, was not significantly different at any capnic level, as was the case with respect to each of the functional parameters in normal tissue. The ability to reduce blood flow and increase mean transit time through hypocapnia has significant implications in thermal therapy, since heat dissipation is a major factor in limiting the effectiveness of treatment.

Animals↗
PubMed2001

3-D simulation of craniofacial surgical procedures.

An integrated system for simulating craniofacial surgical procedures is presented. The system computes nonlinear soft-tissue deformation due to bone realignment. It is capable of simulating bone cutting and bone realignment with integrated interactive collision detection. Furthermore, soft-tissue deformation and cutting due to surgical instruments can be visualized. The system has been tested with several individual patient data sets. Simulation processes are based on a 3-D model of a patient's preoperative bone structure of the skull derived from a computer tomography scan and on a 3-D, photorealistic model of the patient's preoperative appearance obtained by a laser range scanner. The multi-layer soft-tissue model is represented by nonlinear springs. Very fast and robust prediction of nonlinear soft-tissue deformation is computed by optimizing a nonlinear cost function.

Cephalometry↗
PubMed1986

Growth of human renal carcinoma in soft agar colony formation assays measured by computer-assisted volume analysis.

Technical methods for assessing the growth and chemotherapy sensitivity of human tumor cells growing in soft-agar culture have been less than ideal. Within the past year, there have been reports of studying the extent of growth of human tumor cells in these cultures by quantitating the change in cumulative volume for the growth units observed. The present report describes the results of computer-assisted volume analysis applied to soft-agar cultures of cells from 74 primary renal cell carcinomas, 14 primary transitional cell carcinomas of the renal pelvis, and four different human renal cell carcinoma xenografts. The extent of growth in vitro observed for cells from freshly excised human renal tumors showed the expected and statistically significant relationship to tumor grade and stage. The renal cell carcinoma xenografts proliferated to a much greater extent in vitro than the cells from freshly excised human renal carcinomas. The fundamental growth limit of 10(9) micron. cumulative growth unit volume per plate was confirmed by this series of experiments. Computer-assisted volume analysis appears to be a useful method to study the growth of freshly excised human renal carcinoma cells in vitro.

Agar↗
PubMed1994

Computer-assisted quantitative description of chromatin pattern in soft tissue tumors of the adult.

The chromatin pattern in Feulgen-stained nuclei from soft tissue tumors was quantitatively described by means of computer-assisted microscope analysis. The morphonuclear parameters described densitometric, run length, and co-occurrence matrix features. The present series of cases, which relied upon archival (ie, formalin-fixed, paraffin-embedded), tissues, included 19 benign (9 lipomas and 10 leiomyomas) cases, and 49 malignant (31 primitive non-recurrent, 14 primitive locally recurrent, and 4 metastatic) cases. The 31 primitive nonrecurrent cases included 12 liposarcomas, 11 leiomyosarcomas, 4 rhabdomyosarcomas, and 4 malignant fibrohistiocytomas. The results show that the quantitative description of chromatin patterns in Feulgen-stained nuclei made it possible to distinguish between certain benign and malignant soft tissue tumors. However, this was true only when specific histopathologic groups were taken into consideration. Indeed, the lipomas were markedly different from the liposarcomas, whereas the leiomyomas closely resembled the leiomyosarcomas. The quantitative description of the chromatin patterns also made it possible to identify certain clinically aggressive soft tissue tumors. In this context, the authors observed that the chromatin pattern in the cell nuclei from the group of patients whose tumors had recurred less than 10 months after first surgery was significantly more heterogeneous and less condensed than in the cell nuclei from patients whose tumors had recurred more than 10 months after this surgery. In the same manner, the morphonuclear parameters under study made it possible to establish a more marked distinction between the primitive and recurrent soft tissue tumors that developed a metastasis between 3 and 48 months after the diagnosis, and those tumors free of metastasis until 38 months after the diagnosis. The former group exhibited cell nuclei with a chromatin pattern markedly more condensed and heterogeneous than in the case of the cell nuclei belonging to the latter group.

Adult↗
PubMed1983

Soft-tissue hemorrhage in hemophiliac patients. Computed tomography and ultrasound study.

Fifty-four hemophiliac patients underwent a total of 94 studies using computed tomography (CT), ultrasound, or both. Not only common bleeding sites such as the iliopsoas muscles but also several unusual sites were encountered: these included the iliac bone, bowel wall, mesentery, rectus abdominis muscle, retroperitoneum, bladder wall, and scrotum. Both modalities gave comparable results, and each was helpful in (a) establishing the diagnosis, (b) evaluating the extent of bleeding and its effect on adjacent organs, and (c) demonstrating regression after treatment.

Abdomen↗
PubMed1984

The comparative value of bone scintigraphy and computed tomography in determining bone involvement by soft-tissue sarcomas.

In seventeen patients with a soft-tissue sarcoma, bone scintigrams were found to be more useful than computed tomograms for evaluating bone involvement. The scintigrams had higher predictive value and higher sensitivity, as there were no false-negative or false-positive scintigrams, while there were three false-positive computed tomograms. Accurate scintigraphy requires the use of high-resolution static gamma-camera images that show the tangential relationship between tumor and bone. The images that are usually made in surveying the skeleton for metastatic disease--routine whole-body bone scans, or even gamma-camera images that provide only anterior and posterior views--are inadequate. They did not demonstrate the true relationship of the tumor to bone in the patients in this study when activity within the tumor itself was superimposed over bone. In such patients, properly selected oblique views sometimes showed that the tumor was clearly separate from normal bone activity. Determination of the relationship of the soft-tissue tumor to bone is an important part of the accurate anatomical staging that is required to select appropriate surgical management.

Adolescent↗
PubMed2000

BiGGER: a new (soft) docking algorithm for predicting protein interactions.

A new computationally efficient and automated "soft docking" algorithm is described to assist the prediction of the mode of binding between two proteins, using the three-dimensional structures of the unbound molecules. The method is implemented in a software package called BiGGER (Bimolecular Complex Generation with Global Evaluation and Ranking) and works in two sequential steps: first, the complete 6-dimensional binding spaces of both molecules is systematically searched. A population of candidate protein-protein docked geometries is thus generated and selected on the basis of the geometric complementarity and amino acid pairwise affinities between the two molecular surfaces. Most of the conformational changes observed during protein association are treated in an implicit way and test results are equally satisfactory, regardless of starting from the bound or the unbound forms of known structures of the interacting proteins. In contrast to other methods, the entire molecular surfaces are searched during the simulation, using absolutely no additional information regarding the binding sites. In a second step, an interaction scoring function is used to rank the putative docked structures. The function incorporates interaction terms that are thought to be relevant to the stabilization of protein complexes. These include: geometric complementarity of the surfaces, explicit electrostatic interactions, desolvation energy, and pairwise propensities of the amino acid side chains to contact across the molecular interface. The relative functional contribution of each of these interaction terms to the global scoring function has been empirically adjusted through a neural network optimizer using a learning set of 25 protein-protein complexes of known crystallographic structures. In 22 out of 25 protein-protein complexes tested, near-native docked geometries were found with C(alpha) RMS deviations < or =4.0 A from the experimental structures, of which 14 were found within the 20 top ranking solutions. The program works on widely available personal computers and takes 2 to 8 hours of CPU time to run any of the docking tests herein presented. Finally, the value and limitations of the method for the study of macromolecular interactions, not yet revealed by experimental techniques, are discussed.

Algorithms↗
PubMed2003

Early experience with computed tomographic angiography in microsurgical reconstruction.

Preoperative angiography is frequently used in the planning of microsurgical reconstruction. However, several potentially devastating complications can result from angiography, including arterial occlusion and pseudoaneurysm. Computed tomographic angiography is a relatively new technique that can provide detailed information about vascular anatomy as well as soft and bony tissue without the risks of traditional angiography. In addition, three-dimensional image reconstruction uniquely demonstrates anatomical relationships among blood vessels, bones, and soft tissue. Fourteen computed tomographic angiograms were obtained in 10 patients undergoing microsurgical reconstruction of the head and neck, lower extremity, or upper extremity. The average patient age was 46.9 years (range, 22 to 67 years). Charges related to the computed tomographic procedure were compared with those of conventional preoperative imaging for microsurgical repair. At our institution, the average computed tomographic angiogram charge was 1140 US dollars, whereas the average charge for traditional arteriography was 3900 US dollars. When compared with intraoperative evaluation, computed tomographic angiograms demonstrated clinically relevant surgical anatomy. No complications were noted for the radiographic procedure or after free flap reconstruction. Computed tomographic angiography provides high-resolution, three-dimensional arterial, venous, and soft-tissue imaging without the risks of traditional angiogram and at a lower cost.

Adult↗
PubMed1983

Computed tomography of the middle ear in the evaluation of cholesteatomas and other soft-tissue masses: comparison with pluridirectional tomography.

Computed tomographic (CT) scans and tomograms of 60 patients with various soft-tissue masses of the middle ear, including 30 with cholesteatomas, were studied. CT produced excellent images of middle ear soft-tissue masses and appears to be the diagnostic method of choice for cholesteatomas, glomus tympanicum tumors, and other soft-tissue masses. In one patient CT demonstrated pneumolabyrinth resulting from postsurgical fracture of the footplate of the stapes. Pneumolabyrinth is a newly reported CT finding in stapes footplate fracture.

Adolescent↗