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At least 235 records · Page 13Linked to original sources

A three-dimensional evaluation of human facial asymmetry.

Soft-tissue facial asymmetry was studied in a group of 80 young healthy white Caucasian adults (40 men, 40 women) with no craniofacial, dental or mandibular disorders. For each subject, the 3-dimensional coordinates of 16 standardised soft-tissue facial landmarks (trichion, nasion, pronasale, subnasale, B point, pogonion, eye lateral canthi, nasal alae, labial commissures, tragi, gonia) were measured by infrared photogrammetry by an automated instrument. The form of the right and left hemifaces was assessed by calculating all the possible linear distances between pairs of landmarks within side. Side differences were tested by using euclidean distance matrix analysis. The mean faces of both groups were significantly asymmetric, i.e. the 2 sides of face showed significant differences in shape, but no differences in size.

Adult↗

Co-existence of oblique pinnae and congenital heart disease.

The paper reports a syndrome in which oblique placement of one or both the pinnae on face was found to co-exist with congenital anomalies of heart like VSD, PDA and Tetralogy of Fallot, etc. Although clinically discernible in 90% of the subjects, objective evidence of obliquity of pinna was documented by photogrammetry. The values for the ear inclination in subjects categorized clinically as normally placed pinna were 7.9 degrees +/- 3.39 degrees with range 2 degrees-17 degrees. In contrast, subject where the pinna was clinically categorized as oblique had mean AEI 16.5 degrees +/- 5.81 degrees with a range 5 degrees-33 degrees. Eighteen of the 20 subjects with oblique pinna were demonstrated to have some congenital anomaly of heart as indicated by clinical and echocardiographic examination. In contrast, in subjects with normally placed pinna only 3 out of 34 possessed clinical heart defects. Presence of oblique pinna indicates a thorough search for undetected heart defects.

Adolescent↗

[Biomechanical study on the optimal running route for anterior cruciate ligament reconstruction].

The purpose of this study was to determine the isometric points for anterior cruciate ligament (ACL) reconstruction and to investigate notch impingement with isometric reconstruction. The length pattern of ACL was assessed by three-dimensional bi-plane X-ray photogrammetry for determining the isometric point for ACL reconstruction. The isometric points were studied in six fresh cadaveric knees with no injury in any ligament. Five femoral and four tibial attachment sites were selected for intra-articular reconstruction. In each knee, 20 different combinations were studied. For extra-articular reconstruction, three femoral and three tibial sites were selected. In these knees, nine different combinations were studied. One isometric point for intra-articular ACL reconstruction was a combination of the 5-mm superior posterior point from the femoral attachment of the ACL and the center point of the tibial attachment. The other was a combination of the anterior-proximal edge of the femoral attachment and anterior edge of the tibial attachment. There were no isometric points for extra-articular ACL reconstruction. To investigate notch impingement, eight cadaveric knees were studied. One femoral and three tibial attachment sites were selected. For the reconstructed ligaments, 8-mm and 10-mm cables were used. In each cadaveric knee, six different conditions were studied. When the tibial hole was positioned in the center of the attachment of ACL with an 8-mm graft, then notch impingement did not occur. When the tibial drill holes were positioned in a more anterior position, then notch impingement occurred in all the cadaveric knees in which an 8-mm graft was used. With the 10-mm grafts, notch impingement occurred in all three bony tunnel conditions. In these conditions, notch impingement occurred widely from the medial side of the roof to the wall of the lateral femoral condyle. Thus, if the graft diameter is greater than 8 mm, adequate notch plasty must be performed.

Anterior Cruciate Ligament↗

Flexibility in the scoliotic spine: three-dimensional analysis.

The purpose of this study was to measure the three-dimensional geometry of scoliosis by using biplane radiographic photogrammetry and to evaluate the flexibility of the deformed spine. Thirty-one patients with idiopathic scoliosis underwent analysis. There was a significant correlation between the degree of the scoliotic angle in the frontal plane, kyphotic angle in the sagittal plane, and the rotational angle of the apical vertebra. Hypokyphosis was associated with a scoliotic angle > 40 degrees in the frontal plane. Similarly, hypokyphosis was related to increased rotation of the apical vertebra (p < 0.01). Although the scoliotic angle was decreased by traction in all cases, axial rotation was less corrected in those patients with scoliotic angle > 40 degrees. This suggests that the rotational stiffness at the apex is related to the degree of the rotational angle of the apical vertebra and to the degree of the frontal curve.

Adolescent↗

New perspectives on bone densitometry.

Methods of bone mineral density measurement are presented. Radiological photogrammetry, single photon absorptiometry, dual photon absorptiometry and dual energy X-ray absorptiometry are described. Mode of work of densitometers and their characteristics ares presented. Modern development of densitometric equipment and possible application in diagnosing of osteoporosis is discussed.

Adult↗

Craniofacial growth: a three-dimensional soft-tissue study from 6 years to adulthood.

Normal facial growth and development was analyzed through indirect anthropometry in a mixed longitudinal and cross-sectional investigation; 2,023 examinations were performed on 1,156 healthy Caucasian children and adolescents between 6 and 17 years of age and on 191 young adults. Three-dimensional coordinates of 22 facial landmarks were collected with the Three-Dimensional Facial Morphometry method by automated infrared photogrammetry. Selected three-dimensional parameters (linear distances, angles, and a ratio), describing facial height, width, depth, and convexity on the horizontal plane, were calculated and averaged for age and sex. Within each age group, most linear distances were significantly larger in males than in females, with some exceptions in the 11 to 12 age group, where female growth velocity showed a spurt. In females of the 14 to 15 age group the face had almost completed growth; in males of the same age group, a large increase was still to occur to attain adult values. The sexual dimorphism of the parameters calculated did not appear in the different parts of the face to the same extent: a large part of male facial preponderance occurred in the lower third of face. From 6 years of age to adulthood, the soft-tissues in the facial lower third increased by about 23% (males) and 17% (females), in the middle third by about 18% (males) and 13% (females), and in the upper third by about 16% (males) and 9% (females). The male vs. female comparisons within each age group suggested a sexual dimorphism in the timing of soft-tissue facial growth, but an overall similar attainment of different adult dimensions.

Adolescent↗

The Korean American woman's nose: an in-depth nasal photogrammatic analysis.

OBJECTIVES: To assess the differences in nasal anthropometric measurements between Korean American women and North American white women and to perform an in-depth nasal index calculation. METHODS: This anthropometric survey included a volunteer sample of Korean American women (n = 72) aged 18 to 35 years with Korean parents and no previous nasal surgery or trauma to the nose. Standardized and referenced frontal, lateral, and basal photographs of the nose were taken of the subjects and 22 standard anthropometric measurements of the nose were determined. Results were compared with published standards for North American white women. In addition, 18 nasal indices were calculated and compared with the published standards for North American white women. RESULTS: The Korean American woman's nose did not fit the neoclassic facial canons. Compared with North American white women, 20 of 22 nasal measurements in Korean American women were found to be significantly different. Nasal indices also revealed significant differences in 16 of the 18 that were calculated. The Korean American woman's nose exhibits less rotation, has a flatter dorsum, and is more flared at the alae, with less definition of the nasal tip. CONCLUSIONS: The average Korean American and North American white female nasal anthropometric measurements are very different. As cosmetic surgery becomes more popular among Asian Americans, our findings bolster the need for a broader view of facial analysis and transcultural aesthetics.

Adolescent↗

Multiple-slit illumination of the optic disc.

A modification to a photo slit-lamp illuminator adds detail to the human optic disc surface by projecting onto it a pattern of fine parallel lines. These stripes curve as they traverse the disc, and its surface contour is revealed. Application of this technique may improve the reliability of methods used to quantitate disc topography.

Evaluation Studies as Topic↗

Classification of human cataracts.

A stereoscopic system of lens photography was developed and was applied in the classification of different forms of cataract. Lenses, after surgical extraction, can be classified by a technician, independent of ophthalmological collaboration. This system meets the needs of the laboratory scientist and has been adopted by the Cooperative Cataract Research Group.

Cataract↗

Optic disc parameters and onset of glaucomatous field loss. I. Methods and progressive changes in disc morphology.

Serial stereoscopic fundus photographs taken in known relationship to the onset of glaucomatous visual field loss on 12 eyes were intermixed with those from 206 age- and race-matched controls and analyzed in randomized masked fashion. Progressive changes in the size, shape, or contour of the disc, and a newly described parameter, thickness of the nerve fiber layer as it crosses the disc rim, were readily apparent by the time of onset of glaucomatous field loss in all but two abnormal eyes (one case). In the latter instance, direct comparison of stereophotos indicated progressive pallor of the remaining disc tissue. Serial stereophotographs appear superior to fundus drawings for anticipating glaucomatous field loss.

Glaucoma↗

Optic disc parameters and onset of glaucomatous field loss. II. Static screening criteria.

Stereoscopic fundus photographs of 17 abnormal eyes, taken in known temporal relationship to the onset of glaucomatous visual field loss, and 206 eyes of age- and race-matched controls were examined in randomized masked fashion. Width of the narrowest remaining disc rim, size of the vertical and horizontal physical cups, contour of the temporal and nasal slopes (vertical ovalness), and a newly described parameter, thickness of the nerve fiber layer as it crosses the disc rim, were all useful for distinguishing patients with impending or established visual field loss. None, however, was as effective as defects in the nerve fiber layer, the only parameter displaying sufficient promise as a clinical screening tool to warrant initiation of large-scale prospective evaluation.

Glaucoma↗

Anterior chamber dimensions in patients with narrow angles and angle-closure glaucoma.

The anterior chamber depths, volumes, and diameters were studied photogrammetrically in 273 patients with the clinical diagnosis of narrow angles (dome and plateau iris configuration) and acute, subacute, or chronic angle-closure glaucoma. The anterior chamber depths, volumes, and diameters of all of these patients were significantly smaller than age-, sex-, and refractive error-matched normal controls. Peripheral iridectomy significantly increased the peripheral depth of the anterior chamber and increased the volume of the anterior chamber by 14 microL without changing the central depth.

Adult↗

Reproducibility of optic disc measurements with computerized analysis of stereoscopic video images.

Computerized digital image analysis of the optic nerve head was performed using a simultaneous stereoscopic video camera system to provide rapid, quantitative measurements of optic nerve head topography. Determination of the variability of the measurements is required to estimate the magnitude of optic nerve change over time that can be reliably detected. Total variability, operator variability, and interoperator variability were studied. Total variability was assessed by analyzing ten sets of video recordings made in each of seven eyes of seven normal subjects, and in seven eyes of seven patients with glaucoma. The median coefficients of variation for measurements of total variability in glaucoma patients were as follows: vertical disc measurement, 1.4%; horizontal disc measurement, 2.1%; disc area, 1.9%; vertical cup/disc, 3.9%; horizontal cup/disc, 3.3%; disc rim area, 7.5%; and volume, 7.6%. Operator and interoperator variabilities were considerably smaller in magnitude.

Data Display↗

Simple photogrammetric diagnosis of optic nerve hypoplasia.

It is often clinically important, but also often difficult, to make a definitive morphologic diagnosis of optic nerve hypoplasia in a young child. If, however, one can obtain a photograph of the fundus, including the optic disc, one can make a simple measurement of the horizontal diameter of the optic disc and make this diagnosis. To determine if the horizontal diameter of the optic disc on a 35-mm photographic transparency could be used to separate patients with optic nerve hypoplasia from normal individuals, I measured directly on the transparency the horizontal diameter of the optic disc image taken by a standard 30 degrees field fundus camera with X2.5 magnification in a series of 55 normal eyes, and in 16 eyes with clinically confirmed optic nerve hypoplasia. For the normal series of eyes, the mean optic disc horizontal image diameter was 3.88 mm, with a range of 3.44 to 4.70 mm. For the series of eyes with optic nerve hypoplasia, the mean horizontal diameter was 2.64 mm, with a range of 1.80 to 3.27 mm. There was no overlap between the normal control series and the pathologic series. In subjects with no major ametropia (less than 2.5 diopters of spherical or cylindrical refractive error), a 3.4-mm horizontal diameter optic disc image on a 35-mm transparency can be used as a clinical guide or dividing line for the diagnosis of optic nerve hypoplasia, larger nerves being considered normal and smaller nerves being considered hypoplastic.

Adolescent↗

Contour analysis in plastic and reconstructive surgery.

Three-dimensional measurements of living objects may be made using various biostereometric techniques. Moire topography provides one-step contour line maps. It is a potential low-cost adjuvant to current photographic and cephalometric techniques for documentation of surface deformities. A relatively simple apparatus may be used with instant-processing film to produce immediate contour maps superimposed on the object image on the film. There is significant qualitative information highlighted by the fine resolution of the system. This immediate had data may be quantitatively analyzed by hand with ruler and/or caliper. In the future, off-line quantitative analysis may be made by computer. Geometric constraints of the system and examples of use of the technique are provided. Emphasis is placed on facial asymmetries that are difficult to analyze from plain photographs and inaccessible to data analysis from lateral cephalometric roentgenographs.

Adolescent↗

Parthenogenetic development of Mos-deficient mouse oocytes.

Ovarian teratomas develop in Mos-/- mutant mice produced by homologous recombination. These teratomas are probably derived from oocytes that undergo spontaneous parthenogenetic activation within the ovaries. However, it is not clear how the activated eggs develop into teratomas since embryonic development beyond the four-cell stage was not observed either in vitro or in vivo. In this study, Mos-/- parthenotes derived from in vitro-matured oocytes were cultured using a recently developed medium, KSOM/AA, which promotes a high frequency of preimplantation development by normal embryos. In total, 5% of the Mos-/- oocytes developed to the blastocyst stage. Preimplantation-like and early postimplantation-like embryos were observed in the ovaries of 60-63-day-old Mos-/- mice. These observations support the hypothesis that Mos-/- teratomas are derived from parthenogenetically activated oocytes that undergo early embryonic development up to early postimplantation-like stages within the ovaries. Aberrant meiotic divisions commonly observed in Mos-/- oocytes in vitro may adversely affect preimplantation development and reduce the frequency of blastocyst formation even under the best culture conditions.

Animals↗

Assessment of soft tissue facial asymmetry in medically normal and syndrome-affected individuals by analysis of landmarks and measurements.

We investigated soft tissue facial asymmetry in normal and syndrome-affected individuals ranging in age from 1 year to adulthood. The purposes of our study were to determine if facial asymmetry was greater in syndrome-affected individuals than in normal individuals and, if true, to distinguish those measurements that could be used in routine screening to identify the presence of syndromes in uncertain patients and, lastly, to investigate the causes of measurement asymmetry at the level of the landmarks. The last purpose was possible because we used a stereophotogrammetric method with which the three-dimensional (3D) landmark positions were obtained. In the statistically significantly different measurements, those from the right side were dominant, with one exception in each group, except normal males. In all groups the landmark analyses demonstrated the same trends, and while there was far less patterning in the 3D coordinates, these results were also consistent between the four groups. We compared the statistical findings of the 3D coordinates and measurements and found that there was no predictable relationship between significant findings in the landmarks and the measurements. In particular, we noted that statistical differences in measurements did not infer significant differences in the positions of the landmarks between the right and left sides of the face. Both the normal and syndrome-affected groups appeared to be equally canalized and similarly affected by developmental noise: When the bilateral measurement differences of each syndrome-affected subject were compared to the limits of normal asymmetry, less than 10% of the comparisons exceeded the norms.

Adolescent↗