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Biomedical subjects

F L Bookstein

Publications and source records attributed to F L Bookstein.

At least 55 records · Page 3Linked to original sources
PubMed1994

Drinking during pregnancy decreases word attack and arithmetic scores on standardized tests: adolescent data from a population-based prospective study.

Women (1529) were interviewed in midpregnancy, and a cohort of their children has been examined at various ages. The two standardized tests presented herein are part of a large battery of tests administered when the children were 14 years old. "Word Attack" (n = 462) measures phonological processing on a task involving the reading of pseudowords in nontimed performance. "Arithmetic" (n = 191) measures auditorily processed mental computations in timed performance. Scores on both tests were associated with prenatal alcohol exposure in a dose-dependent fashion. These effects were robust when considered in relation to a wide variety of potentially confounding variables, such as prenatal exposure to tobacco and other drugs, sociodemographic characteristics, and traumatic postnatal events. A variety of alcohol scores were related to these two performance measures, but those involving a massing of drinks on a given occasion had the strongest association. The higher the average number of drinks/occasion, the poorer the offspring performance on tasks thought to underlie numerical problem solving and reading proficiency. Earlier reports of prenatal, alcohol-related neurobehavioral deficits in childhood have now been extended into adolescence.

Adolescent↗
PubMed1994

Maternal drinking during pregnancy: attention and short-term memory in 14-year-old offspring--a longitudinal prospective study.

A large and compelling experimental literature has documented the adverse impact of prenatal alcohol exposure on the developing brain of the offspring. This is the first report of adolescent attention/memory performance and its relationship with prenatal alcohol exposure in a population-based, longitudinal, prospective study (n = 462) involving substantial covariate control and "blind" examiners. Prenatal alcohol exposure was significantly related to attention/memory deficits in a dose-dependent fashion. A latent variable reflecting 13 measures of maternal drinking was correlated 0.26 with a latent variable representing 52 scores from 6 tests measuring various components of attention and short-term memory performance. The number of drinks/occasion was the strongest alcohol predictor. Fluctuating attentional states, problems with response inhibition, and spatial learning showed the strongest association with prenatal alcohol exposure. A latent variable reflecting the pattern of attention/memory deficits observed at 14 years correlated 0.67 with a composite pattern of deficits previously detected on neurobehavioral tests administered during the first 7 years of life. The 14-year attention/memory deficits observed in the present study appear to be the adolescent sequelae of deficits observed earlier in development. As is usual in such studies, not all exposed offspring showed deficits.

Adolescent↗
PubMed1994

Prenatal alcohol exposure, birthweight, and measures of child size from birth to age 14 years.

OBJECTIVES: The purpose of the study was to examine the effect of prenatal alcohol exposure on offspring's weight, height, and head circumference from birth through 14 years of age. METHODS: This longitudinal prospective study examined a cohort of approximately 500 offspring (oversampled for heavier drinkers and stratified for smoking from a population of 1529 women in prenatal care at the 5th gestational month) at birth; 8 and 18 months; and 4, 7, and 14 years of age. Covariates were examined by means of multiple regression. Birth size measures were also examined as predictors of 7-year neurodevelopmental outcomes. RESULTS: Effects of alcohol were observed on weight, length, and head circumference at birth; these effects were not altered by adjustment for covariates including smoking. However, the birthweight effect is clearly transient: although alcohol effects remained observable at 8 months, they were not measurable thereafter through age 14 years. CONCLUSIONS: In this population-based sample, neither birthweight nor any later size measure was as useful an indicator of the enduring effects of prenatal alcohol exposure as were certain neurodevelopmental outcomes.

Adolescent↗
PubMed1991

Landmarks in three dimensions: reconstruction from cephalograms versus direct observation.

A method for generating three-dimensional landmark locations from routine biplane pairs of cephalograms was previously introduced. In this article we compare the locations thus reconstructed to the same configurations as directly recorded through a redundant network of interpoint distances measured with calipers. Six mandibular landmarks were located by both methods on each of 10 dry skulls. With the caliper distances is associated a standard error that can be estimated without explicit remeasurement by the method of "adjustment of networks" familiar from surveying. These standard errors are consistent with the remeasurement error both of the caliper measurements and of the stereolocation from cephalograms; the methods appear to have the same precision, about 0.4 mm per distance. The bias (systematic shift) of the biplane reconstructions with respect to the points used for laying down the calipers may be estimated by regressions of distance discrepancies on the direction cosines of the separations between pairs of landmarks. The caliper tips placed condylion approximately 10 mm medially and a bit forward of where we chose to reconstruct it from biplane cephalograms. The caliper locations of gonion average about 1.6 mm back of their cephalometric position, while those at menton and lower incisal edge are forward by some 1.4 mm. We conclude that the biplane reconstruction (the "three-dimensional cephalogram") is sufficiently accurate for routine clinical and surgical application.

Analysis of Variance↗
PubMed1991

Region of interest issues: the relationship between structure and function in the brain.

The comparison of data sets from individual subjects between imaging modalities is necessary in order to evaluate the normal physiologic responses of the brain or the pathophysiological changes that accompany disease states. Similarly, it is critical to compare data between individuals both within and across imaging modalities. In a collaborative project with a number of university groups, we have developed a system that allows for the within-subject alignment and registration of three-dimensional data sets obtained from different modalities for the same individuals. These data make use of proposed criteria for the optimal solution to positron emission tomography image acquisition and analysis originally established through a series of international workshops. The analysis takes into account errors induced by image acquisition, registration, and alignment with regard to scaling, translation, and rotation. Using the principles of morphometrics and homologous landmarks, the between-subject warping of individual brain anatomy to match that of other individuals, groups or an idealized model can be obtained. Resultant information can provide averaged between-subject data for populations of normal individuals or patients with specific neurologic disorders. Such a system, provides the means by which to compare objectively quantitative data between individuals in a highly automated fashion.

Brain↗
PubMed1990

The Le Fort III advancement osteotomy in the child under 7 years of age.

This is a longitudinal study of 12 patients with craniofacial synostosis syndromes (Crouzon's, Apert's, Pfeiffer's) who underwent Le Fort III advancement under the age of 7 years (average age 5.1 years, range 4.0 to 6.7 years). The average follow-up was 5.0 years and included clinical, dental, and cephalometric examinations according to a prescribed protocol. The study demonstrated that the procedure could be safely performed in the younger child with an acceptable level of morbidity. There was a remarkable degree of postoperative stability of the maxillary segment. However, although vertical (inferior) growth or movement of the midfacial segment was demonstrated, there was minimal, if any, anterior or horizontal growth. Any occlusal disharmony developing during the period of follow-up could be attributed to anticipated mandibular development and could be corrected by orthognathic surgery. The roles of surgical overcorrection and anterior-pull headgear therapy after release of intermaxillary fixation are also discussed. The Le Fort III osteotomy is justifiably indicated during early childhood for psychological and physiologic reasons.

Acrocephalosyndactylia↗
PubMed1989

Microevolution in Miocene Brizalina (Foraminifera) studied by canonical variate analysis and analysis of landmarks.

A stratigraphically oriented series of the Miocene foraminiferal species Brizalina mandoroveensis from Ikang, Cameroon, was analyzed both by conventional multivariate morphometric procedures and by the tensor biometric method of Bookstein (1986; Statist, Sci. 1, 181-142), a method which analyzes sets of landmark points rather than specific variables of shape or size. The conventional analysis used five size-measures upon 170 specimens from five stratigraphic levels; the tensor analysis encompassed six landmarks (12 coordinates) upon 50 specimens. Whereas certain features appeared in both analysis, such as the separation between levels one and five, the techniques did not always agree with respect to the interpretation of those findings or about most details in the sequence of mean phenotypes. The canonical variate analysis bases its ordination upon a general size factor (the meaning of which is obscured by the foreshortening of within-group variation which is built into the technique). The tensor analysis locates a similar ordination using mainly features of shape.

Analysis of Variance↗
PubMed1989

Assessment of ultrasonic computed tomography in symptomatic breast patients by discriminant analysis.

From 95 subjects imaged with both speed of sound and attenuation ultrasonic computed tomography (UCT), quantitative analyses are presented on 40 cases where unequivocal correlating clinical diagnoses are available. Using four attenuation and speed of sound parameters from different regions of interest in the breast, a linear discriminator detects cancer with approximately 90% sensitivity and specificity. Increased confidence in the predictive power of this small study is given by a modern test of predictive power (jackknifing) and by the fact that diagnostic discrimination remains as high as 85% when only two parameters are employed--attenuation and speed of sound in the lesion minus those values in the remaining central mammary tissues. Speed of sound images appear particularly useful in older, fatty breasts where pulse echo ultrasound is particularly lacking. While UCT in the form studied here is not likely to receive wide clinical acceptance in the near future, a combined UCT/pulse echo system might find wide clinical utility if it can be sufficiently convenient and inexpensive.

Adenofibroma↗
PubMed1989

Impact of pre-radiology clinical years on resident performance.

In 1971, the American Board of Radiology dropped the requirement for at least one pre-radiology clinical year (PRCY) of training. However, requiring a clinical year for radiology residents remains a controversial issue. We reviewed 896 rotation evaluation forms involving 62 residents to see if a difference in performance could be detected between residents who entered training without or with at least one PRCY. Forty-five residents had no previous clinical training, whereas 17 had one or more PRCYs. No significant differences were detected in resident performance between non-PRCY and PRCY residents, nor were differences found by sex, age, presence of non-medical postgraduate degrees, or scores on the first part of the National Board of Medical Examiners. No study of PRCY versus non-PRCY residents can be adequately controlled; thus the failure to show a difference in performance must be interpreted with caution.

Adult↗
PubMed1989

Hyperfunctioning and nonhyperfunctioning benign adrenal cortical lesions: characterization and comparison with MR imaging.

The authors evaluated the potential of magnetic resonance (MR) imaging at 0.35 T to permit differentiation of nine hyperfunctioning adrenal cortical lesions from 21 nonhyperfunctioning adrenal cortical adenomas. Both qualitative data (visual assessment) and quantitative data (signal intensity ratios, T1, and T2) were used for tissue characterization. With a 2,000/56-100 sequence (repetition time msec/echo time msec), the majority of lesions were visually isointense to liver. Of 34 quantitative measures, only lesion-liver and lesion-kidney intensity ratios at 2,000/150 showed statistically significant differences among nonhyperfunctioning adenomas, aldosterone-producing lesions, and corticosteroid-producing lesions; however, the authors question the significance of these differences because of the abundant noise associated with the 2,000/150 sequence. The results suggest that nonhyperfunctioning adrenal cortical adenomas cannot be distinguished from benign hyperfunctioning cortical lesions with use of MR imaging at 0.35 T.

Adenoma↗
PubMed1988

The three-dimensional cephalogram: theory, technique, and clinical application.

The Broadbent-Bolton cephalostat produces intrinsically three-dimensional information about cranial form. Yet in the clinical setting, this information has been used primarily two dimensions at a time in the separate study of lateral or posteroanterior cephalograms. In this article we demonstrate an expedient use of existing cephalostat-based data sets to derive certain analyses of three-dimensional form. The technique is essentially the same as that of the Broadbent-Bolton "Orientator," an exploitation of the geometry of the cephalostat to simulate stereophotogrammetry. The three-dimensional method supports the usual biometrics of landmark locations, and takes advantage of a normative data base that is suited for semiautomatic analysis of syndromic data. The principal drawback of the method is its inability to represent curving form in three dimensions. However, in comparison with computed tomography (CT), it involves low radiation dose, is simpler to obtain, has an available normative data base, and is more practical for quantitative or long-term serial analysis.

Biometry↗
PubMed1988

Distinction of hepatic cavernous hemangioma from hepatic metastases with MR imaging.

Twenty-four hepatic cavernous hemangiomas and 91 metastases from a variety of hypovascular and hypervascular primary neoplasms were prospectively studied with magnetic resonance (MR) imaging. In addition to qualitative analysis, quantitative analysis of signal intensity ratios of lesion to normal liver was performed with images obtained with 500/28-30 (repetition time msec/echo time msec) and 2,000/28-150 sequences. Quantitative data did not improve the ability to distinguish hemangiomas from metastases in our series compared with qualitative analysis. Hypovascular metastases, such as colon carcinoma, could be differentiated from hemangioma more frequently (97.5%) than hypervascular endocrine metastases, such as islet cell tumor, carcinoid, and pheochromocytoma (61%). These findings indicate that the utility of MR imaging in differentiating hemangiomas from metastases is dependent on the histologic type of the primary neoplasm.

Diagnosis, Differential↗
PubMed1987

Facial effects of fetal alcohol exposure: assessment by photographs and morphometric analysis.

This study was designed to assess the limits of alcohol-related facial dysmorphogenesis. Standard full face and lateral facial photographs were obtained on 21 7-year-old children who had been exposed gestationally to known, heavy quantities of ethanol. Only two of these children had been previously considered to have definite fetal alcohol syndrome (FAS). Similar photographs of 21 other 7-year-old children with negligible gestational ethanol exposure were obtained for control purposes. Copies of the 42 photographs were given to each of seven expert clinicians who were asked to select any child with an FAS-related facial appearance. Six of seven judges were accurate in identifying children with high levels of alcohol exposure as having a fetal alcohol-affected face. A set of homologous points on the photographs were then digitized and analyzed by newly developed morphometric methods to determine the facial shape characteristics that distinguish the selected photographs of highly exposed children. The analysis confirmed that the judges specifically identified children with facial changes consistent with those previously published as defining the face of the FAS: short palpebral fissures, a relatively long and flat midface, and a retrusive mandible. This methodology may be useful in more accurately delineating the facial phenotype in other conditions diagnosed primarily on the basis of subjective clinical criteria.

Anthropometry↗
PubMed1987

Describing a craniofacial anomaly: finite elements and the biometrics of landmark locations.

An intergroup comparison of cephalometric landmark configurations by the finite-element method elegantly depicts the algebra of some of the size and shape change measures that one may define by reference to those landmarks. In studies of mean differences between groups, the statistical analysis of these finite elements is equivalent to competent statistical analysis of the same data using any other geometric metaphor, such as properly standardized vector descriptions of landmark "movement" or scalar measures, size and shape variables, taken in sufficient variety. In applications to landmark data, the reality of finite-element depictions is purely statistical rather than phenomenological. In the absence of additional evidence, they should not be held either more or less biologically meaningful than other descriptions of the same landmark changes to which they lead. These propositions are exemplified using landmark data from 13 cases of Apert syndrome.

Acrocephalosyndactylia↗
PubMed1987

Mean tensor cephalometric analysis of a patient population with clefts of the palate and lip.

This study was designed to elucidate the net "effect" of primary and secondary palatal clefts on the craniofacial skeleton as viewed in the lateral cephalogram. A tensor cephalometric analysis is reported for 144 patients with cleft lip, cleft palate, or both. The study involves 13 lateral landmarks located in the patients' cephalograms and in the Michigan normative means. The net deformity (total sample) is a reduction of size in all directions, but primarily in the horizontal dimension (ANS-PNS) at the palatal level. Lower face height is affected less than upper face height. The bilateral group shows a considerably greater amount of "net" deformity in the cranial base and reduction in mandibular body length. The effect of cleft of the secondary palate alone is horizontal. The effect of an additional primary cleft is aligned instead vertically in the maxilla and intensifies the reduction of cranial base depth. These findings concur with the literature that attributes these syndromes to different mechanisms with different modes of inheritance.

Adolescent↗
PubMed1986

The mandible in mandibulofacial dysostosis: a cephalometric study.

The lower border of the mandible in mandibulofacial dysostosis is characteristic of the syndrome. Evaluation of the cephalograms by means of the medial axis analysis and inflectional tangents captures the shape deformity. Morphometric data from lateral cephalograms on seven patients, ages 3 through 20 years, are reported: a total of 22 observations on three males and four females. These forms were compared to normal mandibular forms from the University of Michigan University School Study. The curvature of the gonial angle in the study population is not distinguishable from the normal curvature. Relative to this apparently normal region, there is a marked downward displacement of the symphysis that results in the curvature typical of the lower mandibular border in this syndrome. These findings are not consistent with earlier reports.

Adolescent↗
PubMed1986

Three-dimensional computer-assisted design of craniofacial surgical procedures: optimization and interaction with cephalometric and CT-based models.

A computer program is described which aids the clinician in planning craniofacial surgical procedures. It operates on a three-dimensional landmark data base derived by combining posteroanterior and lateral cephalograms from the patient and from the Bolton normative standards. A three-dimensional surgical simulation program based on computerized tomographic (CT) data is also described which can be linked to the cephalometrically based program. After the clinician has selected the number and type of osteotomies to be performed on the patient, an automated optimization program computes the postoperative positions of these fragments which best fit the appropriate normal cephalometric form. The clinician then interactively modifies the design to account for such variables as bone-graft resorption, relapse tendency, occlusal disparities, and the condition of the overlying soft-tissue matrix. Osteotomy movement specifications are easily transferred between the CT-based and the cephalometrically based surgical simulation programs. This allows the automated positioning step to be performed on the cephalometrically based model while the interactive step is performed using the superior image provided by the CT-based model.

Cephalometry↗