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At least 397 records · Page 22Linked to original sources
PubMed1983

Biometry and clinical characteristics of congenital cataracts and microphthalmia in the Miniature Schnauzer.

Forty-two Miniature Schnauzer pups and adults with congenital cataracts and microphthalmia were evaluated by serial ophthalmic examinations, slit lamp biomicroscopic photography, and A-scan ultrasonography. The cataracts were evident when the eyelids opened at 2 weeks, affecting predominantly the lens nucleus and posterior cortex. Lenticonus was evident in 19% of the cataractous lenses. Progression of the cataracts was variable and related to involvement of the equatorial and posterior cortices. Lens-induced uveitis developed in some adult dogs with advanced hypermature cataracts. The globe and lens were smaller than normal in the cataractous eyes, as ascertained by A-scan ultrasonography. Age-matched comparisons of clear lens carrier Miniature Schnauzers and normal Beagles with the cataractous Miniature Schnauzers indicated affected globes and cataractous lenses were reduced 10% to 20% in their anteroposterior lengths. The microphthalmia appeared related to the congenital microphakic cataract.

Animals↗
PubMed1994

Biological variability and measurement error variability in ocular biometry in samoyed dogs.

A-scan ultrasonography was performed in 40 healthy Samoyeds aged 2-5 years. Mydriasis and cycloplegia were induced in all dogs and 25 of the dogs were also sedated prior to the ultrasound examination. Five consecutive A-scans were taken on each eye and the intrasubject variance (measurement error) and true intersubject variance (true biological variation) were computed. The true biological variation was found to be of the same magnitude in both sedated and unsedated dogs, whereas the measurement errors were considerably larger in the group of unsedated dogs compared to the sedated ones. Magnitudes of the measurement errors for the anterior chamber depth and length of the vitreous body in the unsedated group were unacceptable. The sizes of the measurement errors in the sedated dogs were all within an acceptable range.

Animals↗
PubMed1994

The world of biometry.

The International Biometric Society is an international society for the advancement of biological science through the development of quantitative theories and the application, development and dissemination of effective mathematical and statistical techniques. We consider some of the nonscientific and scientific issues being addressed by researchers in and across Regions and Groups of our Biometric world. These run the gamut of theoretical to applied mathematics and statistics with the applications spanning many fields and, not surprisingly, forming a rich source of new theoretical developments.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Prediction of fetal macrosomia by single ultrasonic fetal biometry.

A total of 1,056 fetuses underwent single ultrasonographic measurement of fetal biparietal diameter (BPD), abdominal circumference (AC), femur length (FL), and estimated body weight within five days of delivery. The accuracy of these parameters and estimated body weight equations in the prediction of macrosomia (birth weight > or = 4,000 g) was evaluated. With the use of receiver operator characteristic curves, the optimal cutoff value for each parameter with the best sensitivity, specificity and accuracy was selected. BPDs > or = 9.4 cm had the best sensitivity (68.8%), specificity (74.3%), and accuracy (74.1%). ACs > or = 35 cm had the best sensitivity (81.3%), specificity (81.5%), and accuracy (81.5%). FLs > or = 7.0 cm had the best sensitivity (68.8%), specificity (74.5%), and accuracy (74.3%). The estimated body weight equations did not increase the prediction values whether or not FL was included. Both had the same prediction values at > or = 3,700 g, ie, sensitivity (71.9% vs 71.9%), specificity (92.1% vs 93.8%), and accuracy (91.5% vs 93.2%). The results showed AC to be the best single parameter for predicting macrosomia. Combinations of these parameters were better than a single parameter in the prediction of macrosomia.

Anthropometry↗
PubMedDate not supplied

Biometry with a video-genlock interface and a computer-based image-analyzing system: use as a TV-videopupillometer.

TV-videobiometry is frequently used in biomedical research. Usually, the video images are digitized by computer systems. In contrast, the technique described uses a device known as a video-genlock interface (genlock). The genlock mixes a computer picture with the picture of a video device (synchronization). This technique and the custom-made software provide the following advantages: programmable user interface, low-budget system, user-friendly, manual-based software package, precision, and usefulness in different videobiometric setups such as infrared videopupillometry, which is described. In the demonstrated videopupillometry, the area resolution is 0.0009 mm2 per pixel and the length resolution 0.03 mm per pixel side. The relative coefficient of variation for 20 repeated measurements of pupillary area lies between 0.15 and 0.35%. The mean error of three measurements of a model pupil is less than 1%.

Biometry↗
PubMedDate not supplied

[Biometry in cataract surgery with an implant].

In cataract surgery, the replacement of the opaque lens with an artificial lens is the ideal correction. For the present, the intraocular lens power determination is an essential part of the preoperative evaluation of an eye. The paper presents a short history about the development of implant power calculation, the main formulas used in present, the precise choice of postoperative refraction, the factors affecting accuracy of implant power calculation and some preoperative considerations (patients considerations, intraocular lens characteristics considerations). The final part contains some conclusions about the methods of implant power calculation.

Biometry↗
PubMedDate not supplied

[Biometry of Modiolus capax (Bivalvia: Mytilidae) in Playa Ocotal, Guanacaste, Costa Rica].

155 specimens of mussels (Modiolus capax) were gathered during March 1993 in a subtidal bed, located in northern Ocotal, Guanacaste, Costa Rica. For each individual in the random sample, shell length, breadth and height were measured and total weight, shell weight empty and meat weight were controlled. Analysis of data determined relationships of length to weight, length to breadth and length to height of Lt = 1.31977 Pt + 29.05478, Lt = 0.36605 D + 3.98744 and Lt = 0.50434 A + 2.73786. The mean Conditional Index for the population was 39 +/- 0.07.

Animals↗