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At least 1,207 records · Page 67Linked to original sources
PubMed1979

A roentgen stereophotogrammetric study of implant stability and movement of segments in the maxilla of infants with cleft lip and palate.

Three implants (tantalum pins 1.5 x 0.5 mm) were inserted in each lateral segment of the cleft maxilla of ten infants aged three to 33 months. To check the stability of the implants in the bone the distances between the three implants within each segment were measured by means of roentgen stereophotogrammetry (accuracy 0.05 mm) at intervals of 7, 35, 63, 147, and 287 days after initial examination and at varying intervals thereafter (maximal observation time 833 days). No implants were lost and 18 of 60 measured distances were stable (final changes less than 0.2 mm). The three implants were regarded as a rigid-body model which represented the segment in the calculations of motion. In all infants with complete clefts, transverse narrowing occurred immediately after primary closure of the lip, or primary palate repair, while subsequent movement followed individual patterns.

Child, Preschool↗
PubMedDate not supplied

Roentgenologic assessment of spondylolisthesis. II. An evaluation of progression.

Different degrees of artificial L5-S1 spondylolisthesis were created using a lumbar specimen. Lateral radiographs were obtained of each, with the specimen tilted and/or rotated. The true spondylolisthesis was determined stereophotogrammetrically. The slip, measured on the radiographs, was calculated according to two methods modified from Boxall et coll. No significant difference in accuracy was found between these two methods. The difference in calculated slip between examinations needs to be at least 20 per cent of the sagittal length of L5 to be regarded as a true progression. A true progress of slip of less than 20 per cent is difficult to detect with statistical certainty.

Cadaver↗
PubMed1989

Back shape in brace treatment of idiopathic scoliosis.

This preliminary study has shown that bracing may improve the cosmetic appearance of a scoliotic back although the underlying curve remains unchanged. Thirty-two patients treated with the Boston brace for adolescent idiopathic scoliosis were assessed both roentgenographically and by integrated shape imaging system scanning before and after treatment. The mean follow-up time was 16 months. Surface shape improved in 41% of the patients, whereas roentgenographic improvement occurred in only 9%. Roentgenographic measurements should, therefore, be considered in conjunction with corresponding surface shape measurements in the assessment of brace treatment of scoliosis.

Adolescent↗
PubMedDate not supplied

A simplified roentgen stereophotogrammetric method. Analysis of small movements between the prosthetic stem and the femur after total hip replacement.

A simplified roentgen stereophotogrammetric method is described. It is based on the use of a 50 mm thick reference plate consisting of a carbon-fibre-reinforced polyester box. The patient is placed directly on this box, which makes the methods less cumbersome and more suitable for routine use. The method has been tested in a model experiment designed for detecting small movements between femur and prosthesis at an early stage after total hip replacement. The head and two hemispheres on the prosthesis and three small tantalum balls inserted in the femur serve as reference points. The model experiment now reported shows that the method has acceptable precision.

Femur↗
PubMed1988

Construction of three-dimensional compensators using a simplified moiré camera.

We describe a simple technique for fabrication of tissue compensators using a simplified moiré contouring camera mounted on a commercial simulator. It is shown that high-quality optical enlargement of moiré photographs can be employed to make tissue compensators quickly using 0.4 mm lead sheets. Phantom measurement shows that this technique accurately compensates an irregularly shaped surface.

Humans↗
PubMed1985

Ocular abnormalities in the fetal alcohol syndrome.

Thirty children suffering from the fetal alcohol syndrome (FAS) were compared with 22 matched controls regarding malformations of the eyes and the visual function. All mothers to the FAS children had a documented abuse of alcohol during pregnancy. It was not possible to get reliable, detailed data on drinking habits, nor could it be ruled out that some mothers might have used psychopharmaceutic drugs during periods of the pregnancy. Defects of the outer eye region, or intraocular abnormalities, or both, were found in 27 FAS children (90%). Anomalies of the outer region like ptosis and strabismus were frequently found in the FAS children but were not common in the controls. Abnormalities in the anterior segments and media were found in six eyes. Malformations of the fundus were the most frequently occurring abnormalities in the FAS children. Forty-eight per cent of the eyes showed hypoplasia of the optic nervehead and 49% had an abnormal tortuosity of the retinal arteries. These variables were studied quantitatively by a new photogrammetric method. There were serious consequences to the vision of the FAS children. Nineteen per cent of the eyes has a visual acuity of 0.2 (20/100) or less, and 46% had 0.3-0.6 (20/60-20/30). Almost all controls had normal vision. As maternal alcohol abuse during pregnancy was the only variable which could be traced in every case of FAS, it is appears very likely that alcohol caused the abnormalities of the eyes, possibly through non-specific, intra-uterine growth retardation. It that were the case, ocular abnormalities should be common in children with non-FAS growth retardation. A control study did not support this possibility.

Abnormalities, Multiple↗
PubMed1986

[2D-histograms of the nucleus area and nucleus shape in the diagnosis of astrocytomas and glioblastomas].

8 astrocytomas grade 1-4 and 2 glioblastomas were investigated by a system of automated microscope picture analysis. Histograms of nuclear area and shape from more than 1,000 measured nuclei per tumor were analysed. Both one- and two-dimensional histograms show findings which correlate with the malignant potential of the gliomas. The nuclear area rises with increasing tumor malignancy. On the other hand the measurements of nuclear shape factor are inversely related to the level of malignancy, indicating substantial irregularities in the nuclear structure. The 2D-histograms of both measured parameters also show changes which are correlated with the grade of tumor malignancy and which can be described as shift, loss of compactness and enlargement. The histogram method is discussed as an objectifiable process characterizing important cell and nuclear attributes connected with tumor malignancy. Histograms of both, nuclear area and shape can be helpful in the classification and grading of astrocytomas and glioblastomas.

Adult↗