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At least 217 records · Page 12Linked to original sources
PubMedDate not supplied

Invasive metastasing pulmonary aspergillosis under polychemotherapy.

We report on a female patient who received a polychemotherapy because of an extensive pemphigus vulgaris. Under this therapy, the general condition of the patient worsened. Noncharacteristic symptoms, such as dyspnoea and tachycardia occurred. In spite of comprehensive, also invasive diagnostics, pulmonary foci demonstrable by X-ray morphology and computer tomography could not be specified. In the course of treatment, a cerebral compression symptomatology developed. Post mortem, a pulmonary aspergillosis with abscess-formation in the brain was found. The antigen identification completed the diagnosis. The increasing significance of Aspergillus infections is pointed out. The results of clinical examination and the differential diagnosis as well as the possibility of the diagnosis of pulmonary aspergillosis are demonstrated.

Adrenal Cortex Hormones↗
PubMedDate not supplied

Imaging evaluation of ovarian masses.

Adnexal masses present a special diagnostic challenge, in part because benign adnexal masses greatly outnumber malignant ones. Determination of a degree of suspicion for malignancy is critical and is based largely on imaging appearance. Endovaginal ultrasonography (US) is the most practical modality for assessment of ovarian tumors because it is readily available and has a high negative predictive value. Morphologic analysis of adnexal masses is accurate for identifying masses as either low risk or high risk. The most important morphologic features are non-fatty solid (vascularized) tissue, thick septations, and papillary projections. Color Doppler US helps identify solid, vascularized components in a mass. Spectral Doppler waveform characteristics (eg, resistive index, pulsatility index) correlate well with malignancy but generally add little information to morphologic considerations. Computed tomography can help assess the extent of disease in patients before and after primary cytoreductive surgery. Magnetic resonance (MR) imaging is better reserved for problem solving when US findings are nondiagnostic or equivocal because, although it is more accurate for diagnosis, it is also more expensive. The signal intensity characteristics of ovarian masses make possible a systematic approach to diagnosis. Mature cystic teratomas, cysts, endometriomas, leiomyomas, fibromas, and other lesions can be accurately diagnosed on the basis of T1-weighted, T2-weighted, and fat-saturated T1-weighted MR imaging findings.

Blood Flow Velocity↗
PubMed1999

Validation of a new noncontact catheter system for electroanatomic mapping of left ventricular endocardium.

BACKGROUND: Improvements in cardiac mapping are required to advance our understanding and treatment of arrhythmias. This study validated a new noncontact multielectrode array catheter and accompanying analysis system to provide electroanatomic mapping of the entire left ventricular (LV) endocardium during a single beat. METHODS AND RESULTS: A 9F 64-electrode balloon array catheter with an inflated size of 1.8x4.6 cm was used to simultaneously record electrical potentials generated by the heart and locate a standard electrophysiology (EP) catheter within the same chamber. By use of the recorded location of the EP-catheter tip, LV geometry was determined. Array potentials served as inputs to a high-order boundary-element method to produce 3360 potential points on the endocardial surface translatable into electrograms or color-coded activation maps. Three methods of validation were used: (1) driven electrodes in an in vitro tank were located; (2) waveforms generated from the array catheter were compared with catheter contact waveforms in canine LV; and (3) sites of local LV endocardial activation were located and marked with radiofrequency lesions. Tank testing located a driven electrode to within 2.33+/-0.44 mm. Correlation of timing and morphology of computed versus contact electrograms was 0.966. Radiofrequency lesions marked 17 endocardial pacing sites to within 4.0+/-3.2 mm. CONCLUSIONS: This new system provides anatomically accurate endocardial isopotential mapping during a single cardiac cycle. The locator component enabled placement of a separate EP catheter to any site within the mapped chamber.

Animals↗
PubMedDate not supplied

Temporal organization of the thyroid gland in A/He mice (morphometric investigation).

Biological rhythms of structural elements of the thyroid gland of A/He mice were studied by morphometric methods followed by spectral amplitude and phase analysis on the Minsk-32 computer. The morphological data show that the activity of the organ is maximal at night. The biorhythms have a complex frequency spectrum, including intradian, circadian, and ultradian components.

Animals↗
PubMed2002

Three-dimensional computed tomography evaluation of bony birth canal morphologic deformity (small pelvic cavity) after dome pelvic osteotomy for developmental dysplasia of the hip.

OBJECTIVE: Using three-dimensional computed tomography, we investigated the morphologic deformity of the birth canal in patients with developmental dysplasia of the hip who underwent dome pelvic osteotomy. STUDY DESIGN: Thirty-five normal subjects, 34 patients with developmental dysplasia of the hip who did not undergo dome pelvic osteotomy, and 21 patients with developmental dysplasia of the hip who underwent dome pelvic osteotomy were recruited for the study. We assessed the underlying pelvic deformities together with the postoperative pelvic morphologic changes (iatrogenic deformity). RESULTS: Sagittal diameters of the pelvic contraction were longer, and transverse diameters of the pelvic inlet, expansion, and contraction were shorter in patients after dome pelvic osteotomy than in normal control subjects. CONCLUSION: Anthropoid-type pelvis (a long pelvic inlet diameter in the sagittal dimension while the corresponding measurement in the transverse dimension is short) was observed in as many as 90.5% of patients with developmental dysplasia of the hip after dome pelvic osteotomy.

Bone Diseases, Developmental↗
PubMed1992

Small intestinal mucosal histology in the syndrome of persistent diarrhoea and malnutrition: a review.

Prolonged injury to the small intestinal mucosa is probably the final common pathway by which a variety of noxious influences--nutritional, infective and possibly allergic--perpetuate the syndrome of persistent diarrhoea in children in developing countries. Animal studies have helped to separate the individual effects of malnutrition and diarrhoea on the gut in a way that is not possible in the clinical situation. Early studies in children provided somewhat subjective or semi-quantitative data on intestinal morphology. More recently, the application of computer-assisted quantitative morphological techniques to intestinal mucosae from children with persistent diarrhoea have revealed a spectrum of changes consistent with a cell-mediated immune form of damage. The nature of the antigens that provoke these responses remains to be elucidated. Several reports indicate that in children with persistent diarrhoea clinical severity and prognosis do not necessarily correlate with the degree of small intestinal mucosal damage. Nutritional rehabilitation can be shown to produce a demonstrable improvement in small intestinal crypt cell proliferative activity in children with persistent diarrhoea. It is not yet known for how long nutritional rehabilitation should be continued to ensure complete recovery of the intestinal damage following persistent diarrhoea.

Animals↗
PubMed1997

[Late evaluation with spiral computed tomography of smooth bovine pericardium grafts].

PURPOSE: To evaluate morphologically by spiral computed tomography (SCT) bovine pericardial grafts as aortic substitutes. METHODS: Ten patients were submitted to aortic graft evaluation with SCT. There were 8 ascending and 2 descending grafts. Examination was done after 2 to 7 years post operative. Ages ranged from 49 to 67 years, with 6 male and 4 female patients. All had implanted smooth surface naked pericardial grafts. RESULTS: Surgical result was good in all. Distal dissection persisted in some cases. One had a peri-graft hematoma, 5 had no structural changes and 4 presented mild graft dilatation. There were no graft calcification or pseudoaneurysm. CONCLUSION: Glutaraldehyde preserved naked smooth surface bovine pericardial aortic grafts present satisfactory structural aspect, as seen by SCT, at medium term follow-up. Mild dilatation may be seen in some cases.

Aged↗
PubMedDate not supplied

Electrocardiographic-gated multislice computed tomography for visualization of cardiac morphology in congenitally corrected transposition of the great arteries.

A case of congenitally corrected transposition of the great arteries in a 64-old-woman is presented. Diagnosis was missed by invasive angiocardiography. Electrocardiographic-gated multislice computed tomography not only demonstrated switching of the aortic root and pulmonary trunk but clearly identified fine morphologic details of the cardiac chambers, including the atypical coronary artery pattern.

Coronary Angiography↗
PubMed2004

Study of carpal bone morphology and position in three dimensions by image analysis from computed tomography scans of the wrist.

The morphology and positioning of the carpal bones were studied in three dimensions in 18 normal adults on computed tomography (CT) scans of the wrist. The digital data from each CT scan were processed to extract the carpal bones and to automatically characterize their geometry (geometric centroid, principal axes of inertia) using specific software tools. Biometric and angular parameters were defined for this purpose, and most of these parameters showed a normal distribution. The mean distance between the geometric centroid of the capitate and that of the triquetrum, expressed as a relationship to the length of the first principal axis of inertia of the capitate, was found to be the greatest (157.6%+/-8.4%), whereas the smallest mean distance was between the hamate and triquetrum (91.4%+/-7.3%). In the sagittal plane, the first principal axis of inertia of the bones of the first carpal row projected in front of the vertical axis of the orthogonal reference system, whereas the first principal axis of the capitate projected behind it. Measurements using this methodology are far more numerous than those from standard plain radiographs and have the additional advantage of being independent of the examiner. Future investigations on normal wrists should provide a normal range for each quantitative parameter, and comparative study of normal and pathologic wrist measurements should help to define the most relevant parameters for specific traumatic pathologies of the wrist.

Adult↗
PubMed2000

Morphological and mechanical analysis of the glenoid by 3D geometric reconstruction using computed tomography.

OBJECTIVE: To provide a morphological and mechanical analysis of the glenoid by 3D geometric reconstruction using computed tomography. DESIGN: For patients with different pathologies (Group A=control group, Group B=primary osteoarthritis, Group C=rheumatoid arthritis), the variation in shape of the scapula was characterized by measuring the glenoid version (beta). METHODS: Mapping the computed tomography number and its 3D variation in the bone as a finite element structure. RESULTS: In Group A, the mean value of version was 17 degrees (range 12-22 degrees ). In Groups B and C the mean value of version were 27 degrees (range 4-48 degrees ) and 31 degrees (range 25-31 degrees ) of retroversion. At the center of the glenoid there was a homogeneous area of bony tissue with low computed tomography values and the subchondral bone could be clearly identified. For Group B patients, the computed tomography values were increased at the posterior margin of the glenoid, with a thickening of the posterior area acting as a strengthening column. For the Group C patients, the anatomical modifications were not reproducible between two cases examined. CONCLUSION: Results reveal a great difference between a healthy and a pathological glenoid. RelevanceThe method will be the basis for future study of the pathological characteristics of the joint. Results should provide a new pre-operative insight to help guide the surgeon.

Arthritis, Rheumatoid↗
PubMedDate not supplied

Computer reconstructions of human embryonic craniofacial morphology showing changes in relations between the face and brain during primary palate formation.

During early development of the human facial region, the craniofacial complex undergoes extensive morphogenetic change. The purpose of this study was to generate computer reconstructions of serially-sectioned embryos in order to illustrate major changes in spatial relations that occur between cranial and facial tissues. Five human embryos of stages 16 to 18 from the Carnegie Embryology Collection, which were used in the frontal morphometric study, were selected to illustrate phases of morphogenesis. Serial photographs of frontal sections were enlarged, traced, and digitized for computer reconstruction. The craniofacial complex was divided into components that were similar to those analyzed in a morphometric study [Diewert VM, Lozanoff S: J Craniofac Genet Dev Biol 1993: 13:162-183] to facilitate visualization of changes in regional components. The major changes observed included changes in form of the brain and its ventral contour above the face; enlargement, elongation, and more ventral positioning of the facial prominences relative to the brain; and forward positioning of the eyes and facial tissues relative to cranial components. As the brain became separated from the face at advancing stages of development, the frontonasal prominences narrowed and became vertically elongated, the lateral nasal prominences enlarged and became medially positioned, and the maxillary prominences enlarged and extended anteriorly. Changes in cranial flexion and lifting up and back of the forebrain [Diewert VM, Lozanoff S: J Craniofac Genet Dev Biol 1993:13:184-192.] appear to contribute to withdrawal of the brain from between the facial prominences during early midfacial development before cartilaginous tissues of the chondrocranium develop.

Brain↗
PubMed1993

Dynamic imaging of lung morphology with ultrafast high-resolution computed tomography.

To aid in the diagnosis of lung diseases associated with airway obstruction and air-trapping, we use dynamic ultrafast high-resolution computed tomography (DUHRCT). We obtain a rapid series of ultrafast HRCT scans during a forced inspiratory and expiratory maneuver to demonstrate dynamic lung attenuation changes. Alteration in lung morphology can be seen coincident with changes in lung attenuation during different phases of the respiratory cycle. Lung attenuation changes can be evaluated qualitatively or quantitatively by using time-attenuation curves measured for specific regions of lung. In a normal population, we noted that the lingula is a common site of unsuspected and asymptomatic air-trapping. In subjects with airway obstruction, and in those with cystic lung disease, air-trapping is readily detected, even at the secondary pulmonary lobule level. In some of those cases with air-trapping, a paradoxical decrease in lung attenuation was noted during forced exhalation. Recent development of spiral CT scanners may allow more common usage of a similar dynamic technique. Simple paired inspiratory and expiratory scans, obtained during suspended respiration at the same level, may be sufficient for the detection of air-trapping in many patients.

Humans↗
PubMed2003

Three-dimensional computed tomography imaging in craniofacial surgery: morphological study and clinical applications.

Three-dimensional carniofacial CT imaging has been developed and progressed during the past two decades. The advancement of the hardware and software has made the imaging study more convenient, user friendly, and affordable. Processing and analysis of the imaging data are readily performed on personal computers. Accuracy of the 3-dimensional measurement has been validated. Collaborative study can be achieved with other departments or disciplines, such as orthopedic, otolaryngologic, and dental departments, as well as mechanical engineering department. All the data should be adequately archived as medical imaging data bank for later use. The data can be transferred for production of rapid prototyping models to enhance clinical application. Inter-center sharing of imaging data can be done through common image format. Comprehensive morphological study and clinical information may help to improve or refine treatment planning, which in turn yield better treatment outcome.

Craniofacial Abnormalities↗
PubMed2002

Mammogram synthesis using a 3D simulation. II. Evaluation of synthetic mammogram texture.

We have evaluated a method for synthesizing mammograms by comparing the texture of clinical and synthetic mammograms. The synthesis algorithm is based upon simulations of breast tissue and the mammographic imaging process. Mammogram texture was synthesized by projections of simulated adipose tissue compartments. It was hypothesized that the synthetic and clinical texture have similar properties, assuming that the mammogram texture reflects the 3D tissue distribution. The size of the projected compartments was computed by mathematical morphology. The texture energy and fractal dimension were also computed and analyzed in terms of the distribution of texture features within four different tissue regions in clinical and synthetic mammograms. Comparison of the cumulative distributions of the mean features computed from 95 mammograms showed that the synthetic images simulate the mean features of the texture of clinical mammograms. Correlation of clinical and synthetic texture feature histograms, averaged over all images, showed that the synthetic images can simulate the range of features seen over a large group of mammograms. The best agreement with clinical texture was achieved for simulated compartments with radii of 4-13.3 mm in predominantly adipose tissue regions, and radii of 2.7-5.33 and 1.3-2.7 mm in retroareolar and dense fibroglandular tissue regions, respectively.

Adipose Tissue↗