Using the online and offline change model to improve efficiency for fast-track patients in an emergency department.

BACKGROUND: In 1998 the emergency department (ED) Work Group at Johns Hopkins Bayview Medical Center (Baltimore) worked to reinvigorate the fast-track program within the ED to improve throughput for patients with minor illnesses and injuries who present for care. There had been two prior unsuccessful attempts to overhaul the fast-track process. METHODS: The work group used a change model intended to improve both processes and relationships for complex organizational problems that span departments and functional units. Before the first work group meeting, the work group evaluated the institutional commitment to address the issue. The next step was to find data to fully understand the issues and establish a baseline for evaluating improvements--for example, patients with minor illnesses and injuries had excessively long total ED (registration to discharge) times: 5 hours 57 minutes on average for nonacute patients. ONLINE AND OFFLINE MEETINGS: The work group identified process problems, but relationship barriers became evident as the new processes were discussed. Yet offline work was needed to minimize the potential for online surprises. The work group leaders met separately in small groups with nursing staff, lab staff, x-ray staff, registrars, and physician's assistants to inform them of data, obtain input about process changes, and address any potential concerns. The group conducted four tests of change (using Plan-Do-Study-Act cycles) to eliminate the root causes of slow turnaround identified previously. RESULTS: Total ED time decreased to an average of 1 hour 47 minutes; the practice of placing nonacute patients in fast track before all higher-acuity patients were seen gained acceptance. The percentage of higher-acuity patients sent to fast track decreased from 17% of all patients seen in fast track in January 1998 to 8.5% by February 1999. Patients with minor illnesses and injuries no longer had to wait behind higher-acuity patients just to be registered. The average wait for registration decreased from 42 minutes in January 1998 to 14 minutes in February 1999. Physician's assistant, nursing, and technician staff all report improved working relationships and feeling a team spirit. DISCUSSION: The offline component of the integrated model helped to improve organizational relationships and dialogue among team members, thereby facilitating the effectiveness of online efforts to improve processes. This model has also been applied to improve patient registration (revenue recovery) and the emergency transfer and admissions process.

Ultrasound findings and multiple marker screening in trisomy 18.

OBJECTIVE: To compare detection of trisomy 18 in the second trimester by ultrasound and multiple-marker testing. METHODS: A computerized genetics database was used to identify fetuses of 14-22 weeks' gestation who had comprehensive ultrasound examinations, multiple-marker screening tests (alpha-fetoprotein [AFP]), hCG, unconjugated estriol [E3], and trisomy 18 karyotype. A positive trisomy 18 screen was defined as AFP up to 0.75 multiples of the median (MoM), hCG up to 0.55 MoM, and unconjugated E3 up to 0.60 MoM. A risk of at least 1:190 defined a positive Down syndrome screen. Ultrasound abnormalities were diagnosed prospectively and were confirmed later by retrospective review of sonographic images. RESULTS: From 1988-1997, 30 trisomy 18 fetuses who had comprehensive ultrasounds and multiple-marker testing were identified. Twenty-one (70%) had abnormalities detected by ultrasound, of which the most common isolated finding was choroid plexus cyst. Eleven fetuses (37%) had positive trisomy 18 screens, and two had positive Down syndrome screens, for a total of 13 of 30 (43%) fetuses with positive multiple-marker screening tests. CONCLUSION: We found that ultrasound was more likely to be abnormal than multiple-marker screening tests in fetuses with trisomy 18 (70%) (95% confidence interval [CI] 54, 86 versus 43% CI 25, 61). However, combining the two testing methods yielded the highest detection rate (80% [CI 66%, 94%]).

Using online and offline change models to improve ICU access and revenues.

BACKGROUND: Hospital operational problems that span departments often present formidable challenges because they involve both processes and organizational relationships. Many improvement efforts fail because of relationship issues rather than a lack of understanding of system processes. Reflection on a recent change initiative led to the development of an integrated change model that includes both online and offline components. The online component draws on performance improvement models that provide concepts and tools for use in team meetings to improve processes. The offline component borrows from an earlier tradition of change management that offers guidelines for individuals or teams desiring to be change agents. METHODS: The integrated change model was applied in 1997 at The Johns Hopkins Hospital, Baltimore, to reduce ambulance bypass hours, a chronic problem resulting in $6.7 million in lost revenue annually. The goal was to reduce red alert hours per month by 50%. Three Plan-Do-Study-Act (PDSA) cycles were implemented to test change concepts. RESULTS: There was a significant reduction in red alert hours after the change initiative, with an estimated $6 million in additional hospital revenue. DISCUSSION: The integrated change model may serve as a prototype for improving complex problems in which improving organizational relationships may be as difficult as improving processes and is likely to require a significant amount of work offline. For example, this approach may be particularly helpful for improving processes that span departments or functional units such as reducing cycle times for admissions, first-dose medications, as well as in building and improving integrated delivery systems. The model awaits further testing and evolution.

Effects of maternal infections on fetal adrenal steroid production.

We sought to determine the effect of maternal infections on the fetal hypothalamic-pituitary-adrenal axis. Umbilical cord blood was collected at vaginal delivery after labor (24-44 wk. gestation) from 361 infants of women having normal pregnancy ( apart from preterm delivery in some) and 110 infants of women diagnosed with infections: 86% of these women had amnionitis. Infants exposed to antenatal corticosteroids, being growth retarded, or having developmental abnormalities that would be expected to alter function of the hypothalamic-pituitary unit were excluded. Umbilical cord serum was assayed for dehydroepiandrosterone sulfate (DS) and for cortisol. The data were analyzed by use of SAS. The gestational age of the infants of normal women (35.8+/-0.2 wk., Mean +/- SE) was greater than that of the infants of women having infections (34.3+/-0.4 wk., P = 0.003). Umbilical cord serum levels of DS and cortisol rose as a function of gestational age in both groups of infants (P<0.01). Despite being, on average, 1 wk. younger than the normal infants are, the infants of women having infections during pregnancy had higher serum levels of cortisol and DS than did those infants of the normal women. These data are consistent with activation of the fetal hypothalamic-pituitary-adrenal axis in pregnancies complicated by maternal infections. Such a fetal response could be the consequence of transplacental passage of products of the activated maternal immune system.

Pregnancy outcomes following sonographic nonvisualization of the fetal stomach.

OBJECTIVE: To review pregnancy outcomes when two or more ultrasound scans persistently fail to visualize the fetal stomach. METHODS: A computerized ultrasound database was used to identify all fetuses in which two or more serial ultrasound examinations failed to visualize the fetal stomach. Sonographic images were reviewed retrospectively, with the reviewer blinded to outcome data, to confirm persistent nonvisualization. Pregnancy outcome data were obtained from hospital charts and physicians' office records. Fetal karyotypes, when performed, were obtained from amniotic fluid (AF) culture. The ultrasound findings then were compared with fetal karyotype results and pregnancy outcome data. RESULTS: Of 35,569 ultrasound scans performed during 1991-1996, 26 fetuses (0.07%) with persistently nonvisualized stomachs were identified. Structural defects were detected in 17 fetuses (65%), most often involving the cardiothoracic (n = 5), genitourinary (n = 4), and central nervous systems (n = 4). Karyotypes were obtained in 12 fetuses, and four of them were abnormal. Only five of 17 fetuses (29%) with a structural defect survived. In nine of 26 fetuses (35%) with persistently nonvisualized stomachs, no structural defect was identified. Each of these nine fetuses had abnormal AF volume in its surrounding sac, and the overall perinatal survival in fetuses without a structural defect was only 50%. CONCLUSION: Fetuses with persistently nonvisualized stomachs have an increased incidence of structural defects and AF abnormalities and are more likely to have a poor outcome. A detailed ultrasound examination and fetal karyotype analysis should be performed to evaluate fetuses with persistently nonvisualized stomachs.

Significance of a false-positive trisomy 18 multiple-marker screening test.

OBJECTIVE: To determine if a false-positive trisomy 18 multiple-marker screening test (all three analytes low: maternal serum alpha-fetoprotein [AFP] at most 0.75 multiples of the median [MoM], unconjugated estriol at most 0.60 MoM, and hCG at most 0.55 MoM) indicates increased risk for obstetric complications or is related to maternal weight. METHODS: We accessed our genetic database to obtain multiple-marker screening test results, fetal karyotypes, and pregnancy outcomes from all patients with a normal multiple-marker screening test (n = 3900) and from all patients with a positive trisomy 18 screening test (n = 103) seen in the prenatal diagnosis clinic from 1992 to 1996. During this period, only maternal serum AFP was adjusted for maternal weight. RESULTS: A positive trisomy 18 screen identified five of 12 trisomy 18 fetuses. Women with a false-positive trisomy 18 screen were heavier (175.6 +/- 43.8 lb versus 159.9 +/- 37.9 lb, P < .001) and younger (29.7 +/- 6.5 years versus 32.3 +/- 6.5 years, P < .001) than women with a normal multiple-marker screening test, but were not at increased risk for pregnancy complications. Weight-adjusting all three analytes reduced the false-positive trisomy 18 screen rate by 42% (from 1.9% to 1.1%) but did not change the trisomy 18 detection rate. CONCLUSION: A false-positive trisomy 18 screening test does not indicate increased risk to develop pregnancy complications and may be related to inadequate correction for increased maternal weight.

The relationship between maternal characteristics and fetal and neonatal anthropometric measurements in women delivering at term: a summary.

BACKGROUND: We wanted to determine the relationship between a number of maternal characteristics and various fetal and neonatal anthropometric measurements determined by ultrasound and at birth. METHODS: A total of 1205 term singleton maternal-infant pairs were studied. Various ultrasound measurements obtained at 18, 24, 30 and 36 weeks' gestation and neonatal anthropometric measurements obtained at birth were studied in relationship to various maternal characteristics using univariate and multivariate techniques. RESULTS: Black race, female sex, cigarette smoking, drug use, having a previous low birthweight infant, maternal hypertension and being short or thin or failing to gain weight each resulted in a birthweight decrease of 100 to 300 g. The effect of each of these characteristics on each ultrasound measurement, the timing of the effect, and its ultimate effect on neonatal anthropometric measurements are described. CONCLUSION: The data presented in this paper provide a more complete understanding of the relationship between maternal characteristics, infant sex, and various fetal ultrasound and neonatal measurements.

Morphometric differences in sperm head dimensions of fertile and subfertile stallions.

Gross morphological evaluation of stallion spermatozoa is of clinical value in assessing male fertility in the horse. While of value, methods of subjective sperm classification yield highly variable results. Recent development of computer-assisted sperm morphometry analysis (ASMA) technology has allowed for the objective analysis of sperm head morphometry. In the current study, ASMA was employed to determine morphometric differences in sperm head dimensions between fertile and subfertile stallions. At least 200 spermatozoa from each of 10 fertile and 10 subfertile stallions were analyzed by a commercial ASMA instrument. The mean measurements for length, width, area, perimeter, and width/length for each stallion were recorded and group means compared by a two-sample t-test. The mean measurements for length, area and perimeter were significantly larger in the subfertile than the fertile group (5.77 microm vs 5.33 microm, 12.66 microm vs 11.37 microm and 14.59 microm vs 13.64 microm, respectively). The width of sperm heads from stallions in the subfertile group also tended to be larger than those of fertile stallions. The data suggest that differences in the dimensions of sperm heads may exist between fertile and subfertile stallions.

Second-trimester cystic hygroma: prognosis of septated and nonseptated lesions.

OBJECTIVE: To compare karyotypic, ultrasonographic, and prognostic features of septated cystic hygromas and nonseptated cystic hygromas in second-trimester fetuses. METHODS: A computerized ultrasound data base was used to identify fetuses diagnosed with cystic hygromas at 14-22 weeks' gestation. Photographs from the initial ultrasound were reviewed retrospectively for hygroma type (septated or nonseptated) and any abnormal structural findings. Fetal karyotypes were obtained from amniotic fluid, aspiration of hygroma pouches, or fetal tissue culture. Pregnancy outcome information was obtained from hospital charts and physician office records. Ultrasound findings were then compared with fetal karyotype results and pregnancy outcome data. RESULTS: From 1990 to 1995, 61 fetuses with cystic hygromas were identified. Karyotypes were obtained in 55 fetuses, and pregnancy outcome was available for 59. Abnormal karyotype was present in 42 of 55 fetuses (76%). The most common chromosomal abnormality in septated hygromas was the 45,X karyotype. Trisomy 21 was the most common chromosomal abnormality in nonseptated hygromas. Compared with fetuses with nonseptated cystic hygromas, those with septated cystic hygromas were more likely to be aneuploid (33 of 39 [85%] versus nine of 16 [56%]; P = .03), more likely to develop hydrops (27 of 45 [60%] versus three of 16 [19%]; P = .005), and less likely to be live-born (one of 44 [2%] versus four of 15 [27%]; P = .01). CONCLUSIONS: Fetuses with septated cystic hygromas are more likely to be aneuploid and to develop hydrops, and thus are less likely to be survive than fetuses with nonseptated hygromas.

Quantification of normal head morphometry of stallion spermatozoa.

The heads of stallion spermatozoa were analysed by computer automated sperm head morphometry and the morphometric values of the major subpopulations of sperm heads were assessed. The criteria for normal dimensions of stallion sperm heads are proposed based on the analysis of these measurements. Semen samples were collected from 10 fertile and 10 subfertile stallions, processed by a standard method, smeared onto microscope slides and stained using haematoxylin. At least 200 properly digitized sperm heads were analysed from each stallion. The measurements for length, width, area, perimeter and width/length were recorded for each stallion. All sperm head measurements were placed in a statistical database and multivariate cluster analysis performed. Mean measurements for all parameters of the major clusters of fertile and subfertile stallions were compared by analysis of variance. The ranges of the values of the major clusters of fertile stallions were applied to all stallions to determine the percentage of normal sperm heads for each stallion. The mean values for length, width, area and perimeter in the major cluster of sperm head dimensions of fertile stallions were significantly different from those of the subfertile stallions (P < 0.001). The range of values of the major cluster of fertile stallions was length = 4.9-5.7 microns, width = 2.5-3.0 microns, width/length = 0.45-0.59, area = 10.3-12.1 microns2, and perimeter = 12.9-14.2 microns. On the basis of these values, a significantly (P < 0.001) higher percentage of normal sperm heads were found in the fertile group than in the subfertile group of stallions (52% versus 19%).

Pregnancy outcome following genetic amniocentesis at 11-14 versus 16-19 weeks' gestation.

OBJECTIVE: To compare pregnancy complications in women having genetic amniocentesis at 11-14 weeks versus those undergoing amniocentesis at 16-19 weeks' gestation. METHODS: A genetics data base was used to identify patients retrospectively, those who had genetic amniocenteses by three experienced operators during a 4-year period. The study group consisted of women who had amniocenteses at 11-14 weeks' gestation. For each study patient (early amniocentesis), two controls (amniocentesis at 16-19 weeks) were identified and matched for maternal age, race, and the number of prior spontaneous abortions. An immediate post-procedure complication was defined as any vaginal bleeding, rupture of membranes, or fetal loss occurring up to 30 days after the amniocentesis. A later complication was defined as any fetal death longer than 30 days after the amniocentesis, any preterm delivery, any infant weighing less than the tenth percentile for gestational age, and any neonatal death. Immediate and later complications were compared between the study and control groups. RESULTS. The study group consisted of 314 patients who were matched to 628 controls. Women who had a genetic amniocentesis performed at 11-14 weeks were significantly more likely to have post-procedure amniotic fluid leakage (2.9 versus 0.2%), post-procedure vaginal bleeding (1.9 versus 0.2%), and a fetal loss within 30 days of the amniocentesis (2.2 versus 0.2%) than women undergoing genetic amniocentesis at 16-19 weeks' gestation. Four of the seven patients (57%) with a fetal loss within 30 days of an early amniocentesis had procedure-related complications, such as amniotic fluid leakage, bleeding, and infection, that caused the pregnancy to be lost. No differences were noted between the two groups in the number of preterm deliveries, later fetal deaths, neonatal deaths, or newborns weighing less than the tenth percentile for gestational age. CONCLUSION: Genetic amniocentesis at 11-14 weeks is associated with more post-procedure complications and a higher fetal loss rate within 30 days of the procedure than a genetic amniocentesis performed at 16-19 weeks' gestation.

Prognostic significance of unexplained elevated amniotic fluid alpha-fetoprotein.

OBJECTIVE: To compare the prognostic values of unexplained elevated amniotic fluid alpha-fetoprotein (AF AFP > or = 2.0 multiples of the median [MoM]) and unexplained elevated maternal serum alpha-fetoprotein (MSAFP > or = 2.5 MoM). METHODS: We accessed a data base containing the results of MSAFP screening tests, genetic amniocenteses, and pregnancy outcome data on all women undergoing second-trimester genetic amniocentesis from October 1988 through August 1994. After excluding all patients whose elevated AFP levels had any identifiable cause (positive AF acetylcholinesterase, AF blood contamination, fetal malformation or aneuploidy, multiple gestation, etc), 5743 cases were analyzed. Relative risks (RR) for selected pregnancy complications were determined. RESULTS: Elevated MSAFP, with any AF AFP, was associated with fetal growth restriction (RR 2.5, 95% confidence interval [CI] 1.4-4.4), stillbirth (RR 3.5, 95% CI 1.4-8.3), preeclampsia (RR 2.8, 95% CI 1.1-7.0), and preterm delivery (RR 2.8, 95% CI 2.3-3.4). Elevated AF AFP, with any MSAFP, was associated with preeclampsia (RR 4.4, 95% CI 2.0-10.0) and preterm delivery (RR 1.7, 95% CI 1.3-2.4). Elevation of both AF AFP and MSAFP was associated with preterm delivery (RR 4.0, 95% CI 2.8-5.7). When elevated AF AFP was found in association with a normal MSAFP, the RR to develop preeclampsia was 4.6 (95% CI 1.9-11.2). CONCLUSION: Maternal serum alpha-fetoprotein is a better predictor of late pregnancy complications than AF AFP. However, unexplained elevated AF AFP appears to be especially predictive of preeclampsia.

A standardized test for visual analysis of human sperm morphology.

OBJECTIVES: To develop a method to train and test simultaneously a large number of observers in the practice of visual sperm morphology analysis. DESIGN: Photographs of fixed and stained sperm were prepared. Fields of suitable sperm images were selected and individual images were numbered on each negative. Two tests, which contained a total of 100 sperm images, were created. Thirty images in each test consisted of three repeats of 10 images, while 70 images in each test were unique. The tests were administered to individuals participating in an American Fertility Society postgraduate course. Sperm images were projected on a screen and participants classified each sperm using the method that was used in their own laboratory. SETTING: Postgraduate course of The American Fertility Society. RESULTS: The majority of individuals participating in the tests used some version of the World Health Organization method. The group using the Strict method reported a lower value for the percentage of normal sperm than the groups using the other methods. The variability for the percentage of normal sperm was highest for the Strict method. The degree of classification reversal, i.e., classifying a sperm as normal during one repeat and then reversing the classification during another repeat, was high for all groups (26% to 44% of the classifications). Some degree of improvement was seen from test 1 to test 2. CONCLUSIONS: It is possible to develop efficient and inexpensive methods to train observers to perform the sperm morphology assay. Such methods also enable the objective measurement of the acquisition of proficiency, comparison between different classification methods, and identification of specific differences between observers. Such methods will become more important with implementation of the Clinical Laboratory Improvement Act.

Application of multivariate cluster, discriminate function, and stepwise regression analyses to variable selection and predictive modeling of sperm cryosurvival.

OBJECTIVE: To develop a mathematical model that predicts sperm cryodamage based on the kinematic characteristics of seminal sperm as detected by computer-aided sperm analysis (CASA). DESIGN: Computer-aided sperm analysis was performed on donor semen before and after freezing. An iterative multivariate statistical analysis technique was developed to identify sperm subpopulations and to select the best variables for modeling. Stepwise, multivariate regression was performed on the selected subpopulations to predict the post-thaw percentage of motile sperm from prefreeze kinematic values. SETTING: Andrology laboratories, IVF laboratories, and sperm cryobanks. PARTICIPANTS: Semen donors in an academic research environment. MAIN OUTCOME MEASURES: Identification of predictive kinematic variables; number of sperm subpopulations per sample; number of kinematic variables per subpopulation; prediction error for subpopulation membership; and an equation for prediction of post-thaw percentage of motile sperm from prefreeze CASA variables. RESULTS: The number of subpopulations for each specimen was predicted by 3 to 5 kinematic variables. Straight-line velocity (VSL) and linearity were the most commonly predictive primary variables, whereas curvilinear velocity and amplitude of lateral head displacement were the most commonly predictive secondary variables. The best linear model predicted the post-thaw percentage of motile sperm from the difference in VSL between the subpopulation with the highest value and the subpopulation with the lowest value in each prefreeze specimen. CONCLUSIONS: A small number of consistent kinematic variables accurately described physiologic subpopulations of sperm in prefreeze and post-thaw specimens from different men. An equation based on the characteristics of these subpopulations predicts the post-thaw percentage of motile sperm (i.e., sperm recovery) from simple prefreeze kinematic variables. This equation could improve specimen screening by eliminating the requirements for freezing and thawing in order to identify a specimen's vulnerability to cryodamage.

Use of differentiated cholinergic and second messenger endpoints to evaluate cholinesterase inhibitors.

1. The effects of organophosphorus compounds on the cholinergic properties of a mouse septal neuronal cell line, SN56, were investigated. Treatment of the cells with 10 mumol/L paraoxon or 10 mumol/L diisopropylphosphorofluoridate (DFP) resulted, respectively, in rapid 27- and 11-fold increases of intracellular acetylcholine content. 2. Time-course studies showed that paraoxon maintained its efficacy whereas the effects of DFP decayed quickly, possibly due to rapid hydrolysis and inactivation of DFP in the growth medium.

The effect of cigarette smoking on neonatal anthropometric measurements.

OBJECTIVE: To estimate the effect of maternal cigarette smoking on birth weight, crown-heel length, and ten other neonatal anthropometric measurements. METHODS: Data are from a cohort study on risk factors for fetal growth retardation (FGR) in multiparous women conducted from December 1985 through October 1988. Information on smoking status was collected four times during pregnancy. Data analysis included 1205 singleton infants of women delivering at term. Neonatal anthropometric measurements were obtained within 48 hours of birth, including birth weight, crown-heel length, ponderal index, head and abdominal circumferences, arm length and circumference, femur length and thigh circumference, and triceps, thigh, and subscapular skinfold measurements. Analysis of covariance models were used to assess the independent effect of smoking on each neonatal measurement. RESULTS: Neonates born to women who reported smoking during the first trimester had a 0.6-1.9% reduction in most neonatal anthropometric measurements, resulting in an overall reduction of birth weight of 130 g (4%). Neonates born to women who continued to smoke throughout pregnancy had an average adjusted reduction in birth weight of 189 g (5.9%), compared with a 55 g (1.7%) reduction for neonates born to women who stopped smoking after the first trimester. For women who continued to smoke throughout pregnancy, an increased number of cigarettes smoked was associated with increased reductions in birth weight and neonatal chest and abdominal circumferences. For women who stopped smoking after the first trimester, stopping was a better predictor of neonatal anthropometric measurements than the number of cigarettes smoked early in pregnancy. CONCLUSIONS: Except for the ponderal index, all neonatal anthropometric measurements studied showed some negative effect of maternal cigarette smoking. Head circumference is the measurement least reduced. Smoking cessation is a better predictor of infant size than the number of cigarettes smoked in the first trimester.

Fetal myelomeningocele. Is antenatal ultrasound useful in predicting neonatal outcome?

The objective of this study was to determine if an ultra-sound examination, when performed in the third trimester immediately preceding delivery, is useful in predicting outcome in infants with a myelomeningocele. A retrospective review was undertaken of prenatal ultrasound records and pediatric outcome data on fetuses with isolated myelomeningocele referred to our institution after 28 weeks' gestation during a three-year period. Macrocephaly proved to be the one antenatal ultrasound finding that most correlated with later poor outcomes in infants with myelomeningocele. Macrocephalic fetuses had a longer mean hospital stay after birth and were more likely to have significant respiratory and feeding difficulties. No fetus with macrocephaly had a normal mental score, and all had severe motor deficits on later follow-up testing. The ultrasound diagnosis of macrocephaly identified a group of fetuses with myelomeningocele, who were at highest risk of neonatal problems and developmental delay. Cesarean delivery and aggressive medical treatment of complications did not improve the outcome in these infants. This finding will be useful when counseling patients regarding route of delivery and in pediatric decisions regarding treatment of complications.

Derivation and reliability of kinematic measures of sperm motion.

Studies of sperm movement are relevant in the diagnosis of sperm function and in investigations of cellular biology. Such studies have been traditionally performed by analysing the kinematics of the flagellum or the head. Analysis of the flagellum can provide insights into the cell biological mechanisms responsible for the control of movement. However, the mathematical correspondence between head kinematics and flagellum kinematics is not unique. Therefore, it is not possible to use head kinematics to obtain detailed insights into cell mechanisms or physiology. The accuracy and precision of kinematic measurements are limited by a number of technical and biological factors. Therefore, the interpretation of kinematic data is dependent on a thorough understanding of the assumptions and conditions underlying the analysis. Evaluation of the reliability of kinematic measurements has suffered because no absolute standard for measurement has existed. The development and application of a new standard based on images which were simulated using the equations of motion is described. Because the kinematics of these images are known prior to empirical measurement, the performance of different methods can be determined absolutely. Some kinematic measures are unreliable because they are inappropriate analogues for engineering concepts. The development and use of appropriate engineering measures for the frequency and amplitude of sperm motion is also described. Some types of sperm motion cannot be analysed using kinematic measures (e.g. hyperactivated movement). The concept of the fractal dimension as a more accurate measurement for such motions is introduced. It is concluded that kinematic measurements of sperm motion can provide valuable information about cell biological mechanisms (in the case of the flagellum) and about general membrane and axoneme function (in the case of the head) when the measurements are made under the appropriate conditions, when standard techniques are followed, and when the assumptions underlying the analysis are well understood.

Automated sperm morphometry analysis (ASMA) in the rabbit.

New methods of specimen preparation were developed and a new method of objective, automated sperm morphometry analysis (ASMA) was performed to reduce the technical variation in the rabbit sperm morphology assay. The optimal staining procedure was a modified GZIN stain, which allowed the ASMA instrument to accurately recognize the distal end of the sperm head and to achieve the highest sperm recognition rate (94%). Washing and resuspending sperm to a standard concentration increased the number of sperm per microscopic field in low-concentration samples and reduced the field-to-field variation in all samples. Washing also decreased the number of sperm recognition errors by the ASMA instrument. Mean metric measurements for all sperm were: length, 7.38 microns; width, 3.91 microns; width/length, 0.53; area, 22.10 microns; and perimeter, 19.20 microns. Within-specimen coefficients of variation (CVs) ranged from 0.8% to 5.5% and between-animal CVs ranged from 2.7% to 7.5%. The use of standard specimen preparation techniques and ASMA technology can significantly reduce the technical variation in the rabbit sperm morphology assay.

Automated analysis of toxicant-induced changes in rat sperm head morphometry.

An automated sperm morphometry analysis (ASMA) instrument was developed to obtain measurements of toxicant-induced changes in rat sperm head morphometry. 1,3-dinitrobenzene (1,3-DNB), a testicular toxicant known to affect sperm parameters, was used. Twelve-week-old Sprague-Dawley rats were allocated to a control (C) and to two 1,3-DNB treatment groups (T1 = 15 mg/kg; T2 = 25 mg/kg). 1,3-DNB was administered as a single dose by gavage, and animals were sacrificed 22 days after exposure. Sperm were collected, and morphology smears were made by a standard method. One hundred sperm heads were digitized on each slide, and 8 metric measurements were automatically reported. All measurements tended to decrease in a dose-dependent manner with increasing doses of 1,3-DNB. All values for total width (Wa) and interior width (W(e)) were significantly different from one another. Wa/L was significantly larger in the control than in T1 or T2, and symmetry (S = Wb/Wa) was significantly smaller in the control than in T1 or T2. Multivariate cluster analysis revealed three subpopulations that were also visually distinct. Subpopulation no. 1 was normal, based on published descriptions of normal rat sperm; subpopulation no. 2 was abnormal with a flattened curvature and a normal length; subpopulation no. 3 was abnormal with a foreshortened length and a flattened curvature. T1 and T2 contained significantly more sperm from subpopulation no. 2 and no. 3 than C (T1 = 22% and T2 = 34% vs. C = 8% by cluster analysis). C had 93% normal sperm, while the treatments had 78% and 66%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)