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PubMedDate not supplied

[Influence of the computed tomography in brain disorders. Retrospective study of 10,000 investigations (author's transl)].

On the basis of 10,000 examinations conducted over a period of 4 years and 7 weeks (1974-1979), the authors quantify the influence of computed tomography on neuroradiological diagnostic procedures. Findings during operation, at autopsy, or from follow-up over a sufficiently long period, are used to compare the diagnoses established after computed tomography with those suggested by other investigational methods. The regular increases in pathological observations demonstrates the increasingly precise selection of patients orientated towards the scanner. Computed tomography significantly reduces the frequency of invasive neuroradiological explorations, with both medical and socio-economic consequences. Computed tomography is greatly superior to morphological scintigraphic investigations.

Brain↗

PubMedDate not supplied

Utility of four-dimensional analysis of the acetabular labrum applying motion-gated multislice computed tomography: comparison with arthroscopy and harris hip score.

To analyze the kinesis and morphology of the acetabular labrum (AL) noninvasively, we applied 4-dimensional arthrography with motion-gated multislice computed tomography and compared the results with arthroscopy and Harris hip score (HHS) in 49 symptomatic patients who performed reciprocating hip flexion-extension as we carried out mimic retrospective electrocardiogram-gating acquisition. The kinematics and morphology of AL were classified as stabilized, irregular, or eccentric motion patterns. Of the 9 subjects who had intact or frayed AL on arthroscopy, 7 had stabilized motion (average 50 HHS) and 2 had irregular (44 HHS) motion by CT arthroscopy. Of the 16 without adhesive AL on arthroscopy, 6 had irregular motion (48 HHS) and 4 had eccentric motion (58 HHS). We found that the 4-dimensional arthrography with motion-gated multislice computed tomography can reveal both kinetic and morphological changes of the AL, and facilitate further stratification in subjects with the American Academy of Orthopaedic Surgeons class 0, or 1 or without "detached" morphological findings by arthroscopy.

Acetabulum↗

PubMed2002

Assessment of bone feature parameters from lumbar trabecular skeletal patterns using mathematical morphology image processing.

In this study, bone feature parameters were obtained from digital lumbar vertebral images to determine their potential usefulness in assessing binary trabecular skeletal patterns. The system consisted of a magnification radiographic technique, computed radiography (CR), microfocused X-ray computed tomography (mu-CT), and mathematical morphology image processing. A digital CR image was produced, using a ten-times magnified lumbar vertebral cancellous bone block (1.5 x 1.5 x 1.5 cm(3)). The information was then subjected to mathematical morphology image processing, to extract eight binary trabecular skeletal patterns having different continuities as the operation number ( n) increased. These skeletal patterns were used as test patterns and analyzed quantitatively by calculation of the skeletal pixel percentage (SKP) and star volume analysis (Vsk, volume of skeletal trabecular elements; Vsp, volume of nonskeletal elements). Then the binary skeletal pattern data were converted into the mu-CT format, using a general personal computer, and the images were quantitatively analyzed with mu-CT built-in image analysis software for microstructural indices, fractal dimension analysis, and node-strut analysis. The SKP and Vsk showed an expected decrease as n increased. Concurrently, the Vsp showed an expected increase as n increased. The skeletal thickness (Sk.Th) showed a constant value at n = 1 to 4 and n = 5 to 7, but decreased in a stepwise fashion at n = 1 and n = 5. The skeletal number (Sk.N), bone area fraction (B.Ar/T.Ar) and bone perimeter fraction (B.Pm/T.Ar), decreased as n increased. Skeletal space (Sk.Sp) and perimeter-to-area ratio (B.Pm/B.Ar) increased with increasing n. In the fractal dimension analysis, the values decreased with increasing n and showed changes similar to the image observations. In fact, the SKP, star volume analysis, Sk.N, B.Ar/T.Ar, B.Pm/T.Ar, Sk.Sp, and B.Pm/B.Ar all closely mirrored the observational analysis of the images. Linkage of the skeletal structure as functions of the following parameters could be quantitatively demonstrated. The parameters used were node (Nd) and terminus (Tm). Variations in the total strut length (TSL) and Tm could demonstrate quantitative changes in skeletal structure. These results indicate that the system consisting of a combination of a magnification radiographic technique, CR, mu-CT, and mathematical morphology image processing may be a useful tool for quantitative skeletal structure analysis and the structural assessment of lumbar vertebrae, for the assessment of skeletal structural changes. It is important to choose suitable parameters for the desired structural changes.

Bone and Bones↗

PubMed1997

Effects of airway infection by Pseudomonas aeruginosa: a computed tomographic study.

BACKGROUND: Pseudomonas aeruginosa commonly infects the airways of patients with bronchiectasis. A study was undertaken to examine the relationship between infection of the airways with this pathogen, the morphological pattern of bronchiectasis on thin section computed tomographic (CT) scanning, symptom duration, smoking habits of the patients, and the presence of airflow obstruction. METHODS: Thin section CT scans of 22 adult patients with bronchiectasis and concurrent sputum infected by P aeruginosa (Pa +ve) and those of 45 randomly selected patients not infected by P aeruginosa (Pa -ve) were analysed independently by two thoracic radiologists. Patients with cystic fibrosis were excluded. Each scan was scored at a lobar level for extent of bronchiectasis, severity of bronchial wall thickening and dilatation, predominant pattern of bronchiectasis, presence of mucus plugging, and degree of decreased attenuation of the lung parenchyma. RESULTS: The Pa +ve group had more extensive bronchiectasis and a greater degree of bronchial wall thickening and dilatation on the CT scan than the Pa -ve group; more extensive decreased attenuation was seen in the Pa +ve group. These findings were robust on multivariate analysis; decreased attenuation was also independently related to the duration of sputum production. CONCLUSION: Patients with bronchiectasis infected by P aeruginosa have more extensive and severe bronchiectasis on thin section CT scanning than those without P aeruginosa infection. The bronchi and small airways are both involved, reflecting the end result of complex interactions between host airways and the numerous virulence factors produced by P aeruginosa.

Adult↗

PubMed1995

Temporomandibular joint morphology in children after treatment of condylar fractures with functional appliance therapy: a follow-up study us computed tomography.

The consequences of treating fractures of the temporomandibular joint in children by means of functional appliance therapy remain controversial. In this retrospective study we evaluated the temporomandibular joint morphology of 19 children and adolescents who had sustained a total of 21 condylar fractures between three and nine years previously and who had been treated in this way. Restoration of function was assessed clinically by measurement of mandibular movements, and palpation and auscultation of the joint. Spiral CT was used for the radiological examination with 2D and 3D reconstructions. Eleven patients with 13 fractures of different types showed restoration of normal function with favourable remodelling. The remaining eight patients had only good function with a deformed condyle and significant asymmetry in condylar angle and length of the condylar neck. Four of these cases had also developed bony spurs, neo-arthrosis and a bifid condyle. On the basis of these results, spiral CT imaging appears to be a valuable diagnostic aid in cases of condyle fractures where severe morphological changes are not recognized in earlier conventional X-ray examinations. The authors recommend a quantitative and qualitative analysis of the temporomandibular joint in order to encourage patients' compliance and, in cases of poor cooperation, to extend the treatment time.

Adolescent↗

PubMed1995

Morphology of ganglion cells in the neotenous tiger salamander retina.

The morphology of retinal ganglion cells in the neotenous tiger salamander (Ambystoma tigrinum) was analyzed with the aid of morphometric techniques to determine the diversity of cell types and to evaluate the widely held notion that this form of Ambystoma has a simple retina, with little variance among its cell morphologies. Single-cell staining was achieved through retrograde labeling with horseradish peroxidase injected around the optic nerve sheath followed by a period of several days before tissue processing; 83 well-labelled cells with axons were studied in detail with light microscopy and a computer-aided reconstruction system. Five different morphological cell classes were devised based on broad morphometric criteria such as the dendritic area of influence; the number, length, and complexity of dendritic branches; and the amount of overlap between neighboring dendrites. These classes included small simple, small complex, medium simple, medium complex, and large cells. In addition, a class of cells with numerous varicosities among the dendrites was separately analyzed. These swellings did not stain for catecholamines. Based on optical determinations of the dendritic sublamination pattern within the inner plexiform layer, presumed On-Off cells are present in all subclasses, whereas On cells predominate in the smaller cell groups. Presumed Off cells are well represented in the large field units, although the small total number of cells in this latter class leads to uncertainty regarding the significance of this observation. The diversity of ganglion cell morphology revealed in the present study argues against the assumption that the neotenous tiger salamander has a simple retina, with a relatively invariant set of ganglion cells. On the contrary, it appears that this aquatic form shows morphological diversity in the retinal ganglion cell population rivaling that reported for other vertebrates, including mammals. A functional role for the different cell classes is briefly considered.

Animals↗

PubMed2002

[F-18 fluorodeoxyglucose positron emission tomography in evaluation of tumors of the ENT area: personal results and review of the literature].

The incidence of head and neck cancer is increasing world-wide. In addition to clinical investigation including palpation and endoscopy with biopsy, conventional morphological imaging methods, i.e. ultrasonography, radiography, computed tomography and magnetic resonance imaging (MRI), have a routine role in the diagnosis of malignant head and neck cancer. However, the primary tumour often cannot be found despite extensive examination of the head and neck by means of diverse techniques. Furthermore, for staging purposes as well as for the detection of tumour recurrence after chemotherapy and/or radiotherapy, morphological examination techniques such as CT and MRI are of limited accuracy.

Fluorodeoxyglucose F18↗

PubMed1991

[Morphological changes in the lower incisor of suckling rats induced by large dose of aspirin].

Large doses of aspirin (200 mg/kg or 400 mg/kg, s.c) caused marked hypocalcemia in suckling rats, two hours after administration. The hypocalcemic effect was more evident in two week old rats than in one week old ones. Although the mechanism of aspirin-induced hypocalcemia is not clear at this moment, the drug can be a useful tool for inducing experimental hypocalcemia in suckling rats, besides hormonal and/or nutritional controls. In this report, large doses of aspirin were administrated to new born rats, once at one week after birth, or twice at one and two weeks after birth. The morphological changes of the lower incisor were examined using computer programs which have been developed for the analysis of plane curves such as the traces of the side view of the incisor. Aspirin administration shortened the length of the lower incisor and its labial trace. The width of the incisor, especially in the middle, was also diminished by aspirin administration. These observations suggest that the drug not only induced hypocalcemia in suckling rats but also to some extent suppressed the activity of odontoblasts which produce the dentin of the incisor. Analysis of curvature variance, calculated with the labial trace of the lower incisor, also suggested that large doses of aspirin had two effects. It suppressed mineralization of the teeth through its hypocalcemic effect, and it inhibited synthesis of the collagenous matrix. The computer programs applied in this study have proved useful in determining and analyzing morphological changes of bio-materials which are difficult to measure directly.

Analysis of Variance↗

PubMed1993

Effect of freezing method, thawing temperature and post-thaw dilution/washing on motility (CASA) and morphology characteristics of high-quality human sperm.

Sixteen semen samples, 12 donor and four patient samples of high initial quality, were processed to compare the effect of two freezing methods, two thawing temperatures and the effect of dilution and washing on sperm motility and morphology characteristics. Sperm samples were divided in two equal parts and frozen either by fast vapour freezing or by slow computer-controlled freezing. For each freezing method, half of the straws were thawed at room temperature (22 degrees C), the other half were thawed at 37 degrees C. From each freeze-thawing treatment, one straw was evaluated immediately post-thawing; another straw was washed to remove the cryoprotectant solution. In this way, each semen sample was subjected to eight freeze-thawing treatments. No effect of the freezing method and thawing temperature was observed on motility characteristics evaluated by computer-assisted semen analysis, nor on light-microscopical morphology parameters. Post-thaw dilution and washing, however, exerted a deleterious effect on sperm motility, by reducing percentage motility by 50% compared to unwashed thawed specimens. Linearity and percentage of morphologically normal spermatozoa were obviously impaired, while percentage of abnormal tails and beat cross frequency increased significantly. In general, freeze-thawing was most successful when rapid vapour freezing was followed by 37 degrees C thawing, and when slower computer-controlled freezing was combined with 22 degrees C thawing, causing significant interactions between the freezing method and the thawing temperature. For semen samples of high initial quality, vapour and computer-controlled freezing were equally effective in terms of recovery of morphologically normal, motile spermatozoa.

Cryopreservation↗

PubMed1993

Time-optimized analysis of slit-scan chromosome profiles on a general-purpose personal computer.

Slit-scan flow cytometry provides a method to analyze large numbers of metaphase chromosomes in a relatively short time due to morphological features. The high detection rate requires fast computing for on-line analysis. Up to now, this has been achieved using special-purpose computers, parallel systems or other complex hardware. Here, we describe an algorithm that can be implemented on a general-purpose personal computer. Digitized chromosome profiles can be classified by several criteria especially for the detection of chromosome abnormalities in biological dosimetry. A data set of approximately 4600 profiles was used. Programming in assembler results in an average computing time of about 600 microseconds per profile. Thus on-line evaluation of slit-scanning data appears to become feasible for many flow cytometers running nowadays.

Algorithms↗

PubMed2001

A severe frontal-parietal lobe syndrome following cerebellar damage.

We report a case study of a frontal and parietal lobe syndrome with memory loss after unilateral left-sided cerebellar damage caused by a stroke in a patient with right cerebellar unusual developmental agenesis. The syndrome consisted of severe deficits in planning an organized sequence of events, in visuo-constructive abilities and inappropriate jocularity. These changes are ascribed in part to cerebellar-pontine lesions with resulting frontal lobe diaschisis as documented by single-photon emission computed tomography in the absence of morphological damage to the neocortex.

Adult↗

PubMed1995

Computer-assisted pathology of intraepithelial adenocarcinoma and related lesions: 3-D distribution, structural aberration and discrimination.

To discriminate among intraepithelial neoplasms, we have been relying on tissue microscopy, but pathologists' subjectivity sometimes impairs diagnosis. Even an individual pathologist is sometimes unable to reproduce exactly his or her own previous diagnosis. Are various atypical lesions classifiable in a reproducible way, and if they are, how? The reliability of a diagnosis will be strengthened if we can define the "natural" categories inherent in cells and tissues. Morphometry and statistical analysis using a computer can provide answers. Atypia, a morphological feature of carcinoma, is essentially multivariate. Quantification of a tissue feature requires reducing it to a set of ten or more quantities, including size, shape and position of the nucleus, nucleolus, and the cell itself. The grade of aberration from the norm can be assessed only by a synthetic approach, using a computer for multivariate cluster analysis. This classification has been attempted in adenocarcinoma and related lesions of the lung and pancreas. The categories thus established are reproducible, because the lesions fall into divisions according to their forms. We can also examine the organ distribution of intraepithelial neoplasms by three dimensional (3-D) computer-assisted mapping. To reach a higher level of reliability, as many meaningful features as possible should be taken into account. Particularly, we emphasize the significance of architectural pattern as a biomarker for intraepithelial glandular neoplasms. Computer-aided 3-D structural analysis visualizes the basic skeleton of these neoplasms around which the cells adhere. Instead of the dichotomous tree pattern of normal glands, the tumors basically harbor a 3-D network, tubular or porous, which increasingly deviates from the norm along with the transition from adenoma to well to moderately to poorly differentiated adenocarcinoma. This structural aberration, if recognizable on 2-D sectional images, will serve as a surrogate endpoint biomarker for glandular tumors.

Algorithms↗

PubMed1982

[Quantitative evaluation, indications and value of computer tomography of the lumbar spine].

Beside demonstrating morphological changes, CT enables one to make quantitative measurements of the spinal canal (sagittal diameter, transverse diameter, area of the spinal canal, width of the lateral recess and symmetry of the articular joints). A reduction of the transverse diameter of the spinal canal or asymmetry of the articular joints is associated with an increased and earlier incidence of back pain. In addition, patients with asymmetrical vertebral joints showed more frequent and earlier development of disc prolapse.

Adult↗

PubMed1984

"Cupid's bow" contour of the lumbar vertebral endplates detected by computed tomography.

A characteristic pattern of altered lumbar spine endplate morphology has been frequently noted in patients being evaluated for unrelated indications. The "owl's eyes" configuration of intravertebral disc material on axial transverse computed tomographic sections easily distinguishes this normal variant from pathologic processes. Two representative cases are provided for illustration, one of which on coronal reformations demonstrated the normal "Cupid's bow" contour previously described on frontal plain radiographs.

Adult↗

PubMedDate not supplied

[Morphological diagnosis of pseudocystic tumors of the liver].

Ten cases of pseudocystic hepatic tumors were observed during the past ten years. This entity is very rare in comparison with benign hepatic cysts. Careful analysis of the characteristics of these lesions usually allows to differentiate them from benign cysts. Of importance are wall thickness, mural nodules and fluid/fluid levels on ultrasound and/or computed tomography scanning. In our series, sonography depicted the true morphology of these cystic masses more clearly than computed tomography. If definitive diagnosis cannot be made by morphologic examinations, percutaneous aspiration of the cystic lesion, a simple and safe method, should be considered.

Angiography↗

PubMed1990

[Glomus tumor of the stomach].

A case of the stomach glomus tumour is described in a male of 67, with an asymptomatic clinical course. Results of the angiographic, computer-tomographic examination as well as morphological characteristics of the tumour are presented.

Aged↗

PubMed1996

[The morphology and incidence of maxillary sinus septa].

AIM: The variations and frequency of bony septa in the paranasal sinuses were studied prospectively by means of computed tomography. PATIENTS AND METHODS: The presence and morphology of the septa in the paranasal sinuses were studied in 100 consecutive non-selected adults. RESULTS: CT examinations of 200 maxillary antra showed variations in 26 (13%). There were one complete septum (0.5%), 18 incomplete septa at the base of the antrum (9%) and 7 incomplete septa situated anteriorly (3.5%). CONCLUSION: Bony septa in the sinuses may be clinically relevant during sinus endoscopy or tooth implantation. Preoperative examination may reduce the complication rate of these procedures.

Adult↗

PubMed1981

Quantitation of rat embryonic development in vitro: a morphological scoring system.

In order to realize the maximum potential of whole-embryo culture techniques, definitive parameters must be developed for the quantitative estimation of embryonic growth and development. An objective scoring system has been devised which provides a precise measure of morphological development. Examination of rat conceptuses from dams on pregnancy days 10, 11, 12, and 13 (sperm positive = day 1) led to the selection of 17 morphological features for use in the system. Up to six developmental stages of each feature were defined and assigned scores of 0 to 5. The numerical total of scores for an individual embryo is taken as the overall morphological score (MS). The system was applied prospectively to 103 Sprague-Dawley rat conceptuses aged 9 to 12.7 days (0 = time of copulation). The variation of score with embryonic age (EA, days) was highly linear: MS = 202.28 + 20.932 EA (R2 = 0.991). Thus, the morphological score can be used to compute apparent embryonic age, and the calculated standard error of prediction is +/- 2.2 hrs. The number of somites (SN) was also found to vary linearly with age over this period: SN = -126.23 + 13.217 EA (R2 = 0.982), and could be used to estimate development. However, the standard error for prediction of apparent embryonic age is greater (+/- 3.1 hours) than that for morphological score, and this single feature will not necessarily reflect overall development. Several parameters were examined as estimates of embryonic growth, as distinct from development. Yolk sac diameter, crown-rump length, and head length were found to vary with EA as quadratic functions over this time. Total embryonic protein increased logarithmically with EA and was considered to be the most suitable measure of embryonic growth. Use of the morphological scoring system in embryo culture experiments provides a precise index of embryonic development, aids the detection of retardation or dysmorphogenesis of specific primordia, and allows a quantitative comparison of development and growth.

Animals↗