Diagnostic capabilities of fractal dimension and mandibular cortical width to identify men and women with decreased bone mineral density.

UNLABELLED: Dental panoramic radiographs could be used to screen for osteopenia. We found the fractal dimension to be a good discriminator of osteopenia in both men and women but that the mandibular cortical width (MCW) did not perform as well in men. The fractal dimension may be a valid screening tool. INTRODUCTION: The aim of this study was to assess the diagnostic capability of the fractal dimension and MCW measured from dental panoramic radiographs in identifying men and women with decreased bone mineral density (BMD). METHODS: The MCW and fractal dimension were measured from dental panoramic radiographs as surrogates for BMD. These measures were then compared to the results from dual-energy X-ray absorptiometry (DXA) performed for clinical purposes. A total of 56 subjects with the panoramic radiograph taken within 6 months of the DXA exam were used in the analysis for this study. RESULTS: The area under the curve of the fractal dimension for identifying low BMD (T-score <-1.0) was 0.81 (0.67, 0.95) and 0.78 (0.49, 1.00) for men and women, respectively. For the MCW, the area under the curve was found to be 0.53 (0.34, 0.72) and 0.80 (0.58, 1.00) for men and women, respectively. CONCLUSIONS: In this largely male study population, the fractal dimension was found to be a good discriminator of low BMD in both men and women. The MCW did not perform as well in men.

A new method to assess fetal head descent in labor with transperineal ultrasound.

OBJECTIVES: To assess the feasibility and reproducibility of measuring fetal head station and descent during labor using transperineal ultrasound (TPU) imaging, to compare the evaluation of fetal station through digital examinations with concurrent TPU assessments, and to assess its utility in distinguishing patients whose pregnancy will result in spontaneous vaginal delivery from those who will require operative vaginal delivery or Cesarean section for failure to progress. METHODS: TPU and digital examinations were performed in 88 term laboring patients with a singleton fetus in cephalic presentation. Using TPU imaging, head descent was quantified by measuring the angle between the long axis of the pubic symphysis and a line extending from its most inferior portion tangentially to the fetal skull. Intraobserver and interobserver variability were calculated using variance component analysis. TPU imaging was used to measure the angle of head descent during the second stage of labor in 23 of the women. RESULTS: Analysis of replicated measurements on 75 subjects, by the same observer at approximately the same time, yielded an average SD (intraobserver variability) of approximately 2.9 degrees for the measurement of angle of head descent on TPU examination. A separate variance component analysis on a subset of 15 assessments for which measurements were repeated by a second observer, with two to four replicate measurements obtained by each, yielded an interobserver error estimate of 1.24 degrees. A significant linear association was found between clinical digital assessments and measurement of angle of head descent by TPU examination (P < 0.001). An angle of at least 120 degrees measured during the second stage of labor was always associated with subsequent spontaneous vaginal delivery. In six pregnancies ending in Cesarean section the mean angle of descent measured at last TPU examination was only 108 degrees. CONCLUSIONS: The angle of head descent measured by TPU imaging provides an objective, accurate and reproducible means for assessing descent of the fetal head during labor.

Anatomic relationship between the pubic symphysis and ischial spines and its clinical significance in the assessment of fetal head engagement and station during labor.

OBJECTIVE: To develop a geometric model from computed tomographic (CT) images in non-pregnant women that would objectively reflect clinical head station in laboring patients, against which to test the accuracy of digital examinations. METHOD: CT scans were performed in 70 non-pregnant women to determine, using a geometric model, which angle in a mid-sagittal transperineal ultrasound (TPU) image best coincided with the mid-point of a line drawn between the ischial spines (zero station). Using a geometric algorithm, TPU angles were then assigned for other clinical stations (-5 to + 5). Finally, clinical station was assessed by digital examination and simultaneous TPU assessments in 88 laboring patients to see how closely the clinical examination correlated with the station calculated from the above geometric model. RESULTS: The mean angle between the long axis of the symphysis pubis and the mid-point of the line connecting the two ischial spines for the 70 non-pregnant subjects was 99 degrees . The geometric model developed allowed us to build an algorithm to assign a specific set of theoretical angles to each computed station. Relationships between digitally assessed fetal head station, TPU angle for each station, and the geometrical model created with CT data, are reported. Clinical digital assessment of station correlated poorly with computed station, especially at stations below zero, where it could have greater clinical impact. CONCLUSION: The TPU angle of 99 degrees correlated with zero station, and each station above or below this station could be assigned a specific corresponding angle for reference.

Reduced risk of IDDM among breast-fed children. The Colorado IDDM Registry.

The hypothesis that breast-feeding can provide protection against the development of insulin-dependent diabetes mellitus (IDDM) and would, therefore, be less common among subjects with IDDM was tested with a retrospective design. Cases (n = 268) were selected from the Colorado IDDM Registry and the Barbara Davis Center for Childhood Diabetes (Denver, CO). Two control groups were recruited, one from physicians' practices throughout Colorado (n = 291) and the second through random-digit dialing from the Denver area (n = 188). Cases were less likely to have been breast-fed than controls after adjustment for birth year, maternal age, maternal education, family income, race, and sex [adjusted odds ratio (OR) = 0.70; 95% confidence interval (CI) = 0.50-0.97]. This finding was consistent for both control groups and by birth-year intervals. A greater decrease in risk of IDDM was seen among subjects who had been breast-fed to an older age (for breast-feeding duration of greater than or equal to 12 mo, adjusted OR = 0.54, 95% CI = 0.27-1.08). The amount of IDDM that might be explained by breast-feeding habits (population percentage attributable risk) ranged from 2 to 26%, varying according to the breast-feeding prevalence reported in other studies. Replication of this work in different populations, controlled for the strong secular trends in breast-feeding habits, is critical before the hypothesis of protection is accepted.

Diminution of bone mass in childhood diabetes.

Photon absorption measurements of forearm bone density in 196 insulin-dependent patients, age 6--26 years, were compared with findings in 124 controls. Expected density, gm. Ca/cm.2 bone width (M/W), was calculated from regressions of M/W on ulnar length for white and black male and female controls. There were no significant correlations between M/W differences from expected and serum Ca, Mg, P, or alkaline phosphatase levels, estimated physical activity level, insulin dosage, or the presence of joint contracture. White females averaged 8.2 per cent (+/- 1 S.E.M.) loss of M/W, as against white male average loss of 4.7 per cent +/- 1 and black female loss of 2 per cent +/- 2 (p less than 0.001); the black male population was too small for separate analysis. M/W loss greater than 10 per cent was seen in 29 per cent of white males, 19 per cent of blacks, and 48 per cent of white females (p less than 0.02). When the groups were further divided into those with duration of diabetes less than or equal to five years and those with duration greater than five years, significant reduction in M/W average loss over time was seen with white females (10.6 per cent +/- 1.2 to 3.7 per cent+/- 1.5, p less than 0.0001). Expression of this defect in bone mineralization is controlled by race and sex acting independently of each other.

Colorado IDDM Registry. Incidence and validation of IDDM in children aged 0-17 yr.

The purpose of this study was to determine the incidence of insulin-dependent diabetes mellitus (IDDM) among children aged 0-17 yr for age, sex, season, and urban and rural residence of onset in Colorado. Retrospective registration of new-onset cases was conducted from 1978 to 1980, and then prospective registration continued through 1983 with the use of physician reporting with hospital validation. The annual incidence of IDDM was 15.2/100,000 per year (95% confidence interval [CI] 14.1, 16.3), with little difference between the sexes. The highest incidence was in the 10- to 14-yr age-group for both sexes. There was a seasonal peak of winter onset in those aged 10-17 yr, with similar patterns between sex and ethnic groups. No temporal trend over the 6 yr was seen, although an excess of cases was seen for 15- to 17-yr-old boys in 1980-1982. Rates were similar for urban and rural areas of the state. Case ascertainment was estimated to be 93.2% complete (95% CI 91.5, 95.5). Incidence was similar in Colorado to other populations in the United States at similar latitudes. These data serve as a baseline for evaluation of changes in incidence over time, by region, and for the identification of possible outbreaks.

Colorado IDDM Registry: lower incidence of IDDM in Hispanics. Comparison of disease characteristics and care patterns in biethnic population.

The Colorado IDDM Registry identifies newly diagnosed cases of insulin-dependent diabetes mellitus (IDDM) throughout the state. Hispanics in Colorado are a racial mixture of American Indian and White populations. Because American Indians have a low risk of IDDM, and differing frequencies of HLA antigens and haplotypes are reported for Hispanics and non-Hispanics, we compared incidence rates and disease characteristics. Eligible participants were less than 18 yr of age and Colorado residents at time of diagnosis, diagnosed between 1 January 1978 and 31 December 1983, and on insulin within 2 wk of diagnosis. Subjects were reported by their physicians, and statewide validation of reporting was conducted through review of hospital discharge indexes. Incidence rates for Hispanics (n = 76) were significantly lower than those for non-Hispanics (n = 628), although 95% confidence intervals overlapped for children aged 10-17 yr. Age-adjusted rates were significantly lower in Hispanic than non-Hispanic males, whereas age-adjusted rates for females did not differ. The cumulative risk of IDDM was less for Hispanic males aged 0-17 yr than for non-Hispanic males (P less than .001); cumulative risk among females was males (P less than .001); cumulative risk among females was not different (P = .10). Clinical onset characteristics and medical care at diagnosis were similar. After diagnosis, hospitalizations per 100 person-yr appeared higher in Hispanics, but ketoacidosis and insulin reactions per 100 person-yr were similar. Difference in rate of hospitalizations may have been due to lower response rates among older non-Hispanics.(ABSTRACT TRUNCATED AT 250 WORDS)

Attitudes of at-risk and affected individuals regarding presymptomatic testing for autosomal dominant polycystic kidney disease.

One hundred forty-one individuals with autosomal dominant polycystic kidney disease (ADPKD) and 137 at-risk individuals from 107 kindreds answered a questionnaire to determine knowledge and attitudes about ADPKD and the use of gene linkage analysis for prenatal and postnatal presymptomatic diagnosis. Both groups of individuals displayed a high level of knowledge about the disease. Although 87% of affected individuals considered the recurrence risk of ADPKD high, only 11% of ADPKD did not have children for this reason after diagnosis. Ninety-seven percent of at-risk individuals would utilize gene testing for themselves. Eight-eight percent of ADPKD and 89% of at-risk individuals would test offspring (not significant, NS) and 65% of ADPKD and 50% of at-risk individuals between the ages of 18 and 40 would use prenatal testing (NS). Only 4% of ADPKD and 8% of at-risk individuals between the ages of 18 and 40 would terminate a pregnancy for ADPKD. A greater percentage would terminate a pregnancy for a serious medical problem. The factors influencing presymptomatic testing were analyzed. The data suggest that presymptomatic testing will not substantially modify incidence of ADPKD since it may only occasionally alter reproductive plans.

Reference values for blood findings in relatively fit elderly persons.

In a retirement community group of 73 relatively fit elderly white persons, a cross-sectional study of 53 different blood tests was conducted. The five test categories for blood values were hematology, chemistry, thyroid function, protein electrophoresis, and immunology. Fifteen percent of the blood findings were outside the range accepted as normal by the examining laboratories. Most of the subjects showed between 5 and 10 "abnormal" values within the five test categories. Since the findings were fairly predictable in view of the patho-anatomic changes that accompany aging, and since the manifestations of disease were at most subclinical, only minor alterations in individual management were needed. Subsequent appropriate clinical re-evaluation of these subjects during a six-month follow-up revealed no striking changes. It would appear that the ranges of "normal" reference values may need to be expanded. Although cross-sectional laboratory studies are useful, longitudinal studies seem essential if clinicians are to attain a more valid perspective.

Comparison of hospitalization between nursing home and community residents.

The authors prospectively identified 96 consecutive nursing home residents (NHR) admitted to the medical wards of their affiliated hospitals to determine the outcome of hospitalization for these patients in comparison with 88 admissions in a similarly aged community residents (CR) population. Nursing home and community resident groups were similar in age, sex, marital status, and distribution among the four study hospitals. Dementia was a more common preexisting diagnosis in NHR than in CR. Reasons for admission differed between the two groups. Although NHR experienced a longer hospitalization than CR, frequency and duration of intensive care unit admissions were similar. Fatal outcome occurred more commonly in NHR compared with CR (27 v 11%, P less than .001). Predictors of mortality were examined. Nursing home residents also experienced a higher mortality than CR within the six months after hospitalization (35 v 20%, P less than .005).

Early predictors of postinjury multiple organ failure.

OBJECTIVE: To find a predictive model for postinjury multiple organ failure (MOF). DESIGN: A 3-year cohort study ending December 1992 (first year: retrospective; last 2 years: prospective). SETTING: Denver General Hospital (Colo) is a regional level I trauma center. PATIENTS: Consecutive trauma patients with an Injury Severity Score (ISS) greater than 15, with an age greater than 16 years, and who survived longer than 24 hours. Stepwise logistic regression analysis was performed in all patients (n = 394), in the subgroup of patients with 0 to 12 hours, plus 12 to 24 hours base deficit (BD) results (n = 220), and in a second subgroup of patients with BD plus lactate results at 0 to 12 hours and 12 to 24 hours (n = 106). MAIN OUTCOME: Postinjury MOF. RESULTS: The following variables were identified as independent predictors of MOF in the analysis of all patients: age more than 55 years, ISS greater than or equal to 25, and more than 6 U of red blood cells in the first 12 hours after admission (U RBC/12 hours). In the subgroup with BD results, the same analysis identified age greater than 55 years, greater than 6 U RBC/12 hours, and BD greater than 8 mEq/L (0 to 12 hours), while in the last subgroup analysis including BD and lactate results, greater than 6 U RBC/12 hours, BD greater than 8 mEq/L (0 to 12 hours), and lactate greater than 2.5 mmol/L (12 to 24 hours) were independently associated with MOF. CONCLUSIONS: Age greater than 55 years, ISS greater than or equal to 25, and greater than 6 U RBC/12 hours are early independent predictors of MOF. Subgroup analyses indicate that BD and lactate levels may add substantial predictive value. Moreover, these results emphasize the predominant role of the initial insult in the pathogenesis of postinjury MOF.

The questionable value of medical screening in the small-group health insurance market.

Insurers perform medical screening to assess risk for health insurance in the small-group market. Most reform proposals eliminate screening because it denies coverage to those who need it. This DataWatch empirically analyzes the value of medical screening to insurers. We analyzed claims of two employed populations covered by a large insurer--one screened and the other not screened. We found no significant difference in the amounts claimed by these two populations over six years. This suggests that medical screening could be eliminated in the small-group market without an increase in premiums.

Management practices among primary care physicians and thyroid specialists in the care of hypothyroid patients.

Prospective studies are not available to address various issues commonly encountered in the management of hypothyroid patients. We have conducted a case-based mail survey of American Thyroid Association (ATA) members and primary care providers (PCP) regarding hypothyroidism management issues. A majority of ATA members and a minority of PCPs used antithyroid antibody testing in the evaluation of hypothyroidism. Approximately 2/3 of all respondents indicated that they would treat patients with mild thyroid failure when antithyroid antibodies are negative; 77% of PCPs and 95% of ATA members recommended treatment when antibodies are positive. For a young patient with mild thyroid failure, 71% of ATA members would initiate a full levothyroxine (LT4) replacement dose of 1.6 microg/kg per day or slightly lower; PCPs were more likely to start with a low dose and titrate upwards. For a young patient with overt hypothyroidism, 42% of PCPs and 51% of ATA respondents recommended an initial full LT4 replacement dose. The majority of all respondents would start with a low LT4 dose and adjust the dose gradually in an elderly patient, regardless of the severity of thyroid hormone deficiency. More than 40% of ATA respondents chose a target thyrotropin (TSH) range of 0.5-2.0 microU/mL for a young patient while 39% favored a goal of 1.0-4.0 microU/mL for an elderly patient. PCPs more often chose a broader TSH goal of 0.5-5.0 microU/mL. In conclusion, the current practice patterns of PCPs and ATA members that were elicited in this survey differ significantly in regard to the evaluation and management of hypothyroidism.

Impairment after burns: a two-center, prospective report.

Impairment rating is regularly reported for trauma and other conditions but rarely for burns. The purposes of this study were: (1) to report impairment collected prospectively at our burn center, (2) to relate this impairment to measures of psychosocial and functional outcome, and (3) to compare these data to similar data from another burn center to verify that rating impairment is standardized and that the impairments are similar. We studied 139 patients from the University of Washington (UW) Burn Center and 100 patients from the University of Texas (UT) Southwestern Burn Center. The average whole person impairment (WPI) ratings at the University of Washington were 17% and this correlated with total body surface area burned and days off work. It did not correlate with Brief Symptom Inventory (BSI), Functional Independence Measure (FIM), Short-Form 36-Item Health Survey (SF-36), Satisfaction With Life Scale (SWLS), and the Community Integration Questionnaire (CIQ). Average whole person impairment ratings at UT Southwestern were similar at 19%. Several components of the impairment rating, however, differed at the two institutions. To minimize this variation, we recommend: (1) use the skin impairment definitions of the fifth edition of the Guides to the Evaluation of Permanent Impairment (or the most recent published versions of the Guide), and (2) include sensory impairment in healed burns and skin grafts in the skin impairment.

Time off work and return to work rates after burns: systematic review of the literature and a large two-center series.

The literature on time off work and return to work after burns is incomplete. This study addresses this and includes a systematic literature review and two-center series. The literature was searched from 1966 through October 2000. Two-center data were collected on 363 adults employed outside of the home at injury. Data on employment, general demographics, and burn demographics were collected. The literature search found only 10 manuscripts with objective data, with a mean time off work of 10 weeks and %TBSA as the most important predictor of time off work. The mean time off work for those who returned to work by 24 months was 17 weeks and correlated with %TBSA. The probability of returning to work was reduced by a psychiatric history and extremity burns and was inversely related to %TBSA. In the two-center study, 66% and 90% of survivors had returned to work at 6 and 24 months post-burn. However, in the University of Washington subset of the data, only 37% had returned to the same job with the same employer without accommodations at 24 months, indicating that job disruption is considerable. The impact of burns on work is significant.

The caries-preventive effect of amine fluorides and inorganic fluorides in a mouthrinse or dentifrice after 30 months of use.

The study groups using a dentifrice and mouthrinse both containing fluorides, a dentifrice containing stannous fluoride and a mouthrinse containing sodium fluoride, or a mouthrinse containing sodium fluoride with a placebo dentifrice had a 20.7% to 29.0% lower DMF increment than the control group after 30 months. These differences were significant. The study groups using a dentifrice containing amine fluorides and a placebo mouthrinse, a mouthrinse containing amine fluorides and a placebo dentifrice, or a dentifrice containing stannous fluoride and a placebo mouthrinse had a 13.6% to 22.4% lower DMF increment than the control group. These differences were not statistically significant. There was no significant difference in effectiveness against caries between the use of the organic or inorganic fluoride products.

Prospective assessment of stereoscopic visual status and USAF pilot training attrition.

The role of stereopsis (i.e., the use of binocular cues for depth perception) in military aviation is undetermined. Pilots possessing adequate near stereopsis but having deficient distant stereopsis are thought to have microtropias. Historical reviews of microtropia and research concerning the role of depth perception in military aviation are described. A historical prospective study of student pilots entering U.S. Air Force Undergraduate Pilot Training (UPT) from Oct 1990 through Sep 1991 (FY 90-91) compares UPT attrition rates according to their preselection stereoscopic status (microtropia vs. normal). Univariate and multiple logistic regression analyses do not show significant differences in attrition rates between the two groups, implying that distant stereopsis is not critical to successful completion of UPT. The U.S. Air Force decided in Oct 91 to eliminate near stereoscopic vision screening while retaining distant stereoacuity testing as a criterion for candidates to qualify medically for UPT. Valid rationale for this decision includes simplified and uniform administration of stereoacuity testing, minimizing spurious results, the continued validity of stereopsis testing as a cross-check of other areas of visual function, the uncertain role of stereopsis in critical areas of flight operations, and the large applicant pool competing for a limited number of pilot training positions.

The WeeFIM [R] instrument--a paediatric measure of functional independence to predict longitudinal recovery of paediatric burn patients.

INTRODUCTION: Burns create a myriad of complications that affect the child's developmental, functional and aesthetic status. The WeeFIM is a standardized measure of functional performance developed for use in children 6-months to 8-years of age but with application through adolescence. It includes 18 domains of performance which are scored on a 7-point scale from 'total assistance' to 'complete independence'. In this study, the WeeFIM was used to evaluate the influence of burn size on functional independence and on time to recovery. METHODS: Children, 6 months to 16 years of age, with total body surface area (TBSA) bums of 10-100% burn injury were recruited for a 2-year longitudinal study. Due to unstable WeeFIM measurements on children 6 months to 6 years, analyses on normalized WeeFIM scores among subjects 6-16 years are presented. Children were evaluated at discharge from acute care, 6 months, 1 year and 2 years after burn injury. FINDINGS: In this analysis, 454 WeeFIM evaluations from 249 patients, 6-16 years of age, were reviewed. While mean WeeFIM scores varied significantly at discharge based on the size of burn, there were no significant differences in any of the WeeFIM scales at 24 months post-burn. At 24 months, the mean WeeFIM score for all children, independent of size of their bum, indicated full independence. Hands-on assistance was not required for performing activities of daily living (ADLs). The rates of improvement differed statistically by size of bum. Maximum improvement was attained by 6 months for 10-15% TBSA burns, 12 months for 16-30% burns, 12 months for 31-50% burns and 24 months for 51-100% TBSA. CONCLUSION: The WeeFIM can be utilized by burn centres to describe diminished functional capacity at discharge from acute care for severely burnt children. The tool can be used to track return to baseline independence after a major burn injury in a paediatric population.

Quality controlling interpretive reporting systems in clinical medicine--a changing responsibility.

This paper presents some observations on a number of topics which affect the quality of computer software and includes: current trends in software design, current levels of responsibilities for the various parties involved in bringing automation to clinical medicine, why software development is so difficult to quality control, and certain characteristics of system development which contribute most to the construction of inaccurate models.