Comparison between two- and three-dimensional ultrasound measurements of nuchal translucency.

OBJECTIVE: Fetal nuchal translucency measurement has been introduced as a screening test for the calculation of risk of chromosomal abnormalities. The purpose of this study was to investigate: (1) the feasibility of obtaining nuchal translucency measurements using three-dimensional ultrasound; (2) whether three-dimensional ultrasound could improve and facilitate the required repeated measurements of nuchal translucency; (3) the correlation between two- and three-dimensional nuchal translucency measurement values. SUBJECTS AND METHODS: Between September 1999 and May 2000, in a prospective cohort study, 229 unselected pregnant women with a mean age of 34.6 (range, 20-46) years were examined. The mean fetal crown-rump length was 64.3 (range, 45-84) mm. Nuchal translucency thickness was measured first by two- and then by three-dimensional ultrasound in two planes (three-dimensional mid-sagittal and three-dimensional transverse). An attempt was made to repeat each nuchal translucency measurement three times (totalling nine measurements per patient) and the means of the two- and three-dimensional measurements were compared. The majority (95%) of the measurements were made transabdominally and 5% were made transvaginally. The time limit for each examination was 20 min. RESULTS: With the two-dimensional method, nuchal translucency could be measured in 96.8% of cases. Of these, three measurements could be obtained in 51.7%, two in 23.2% and only one in 25.1%. The three-dimensional examination was successful in 98.6% of cases. Of these, three measurements could be obtained in 60%, two in 22.8% and one in 17.2%. Transvaginally, all examinations were successful. The main reason for the failure of two-dimensional ultrasound was the fetal position, which in some cases precluded the distinction between fetal skin and amnion or the uterine wall. Using two-dimensional ultrasound, 6.3% of the cases of measurement failure were due to an inability to differentiate clearly between fetal skin and amnion, whilst the equivalent value for the three-dimensional method was only 3.3%. For the three-dimensional technique, fetal movement was the main reason for failure. The mean time for both methods was similar (9 min and 10 min for two- and three-dimensional ultrasound, respectively) and the correlation between the measurements obtained by the two- and three-dimensional techniques was very high (r = 0.97). CONCLUSION: The number of fetuses in which nuchal translucency could be measured tended to be higher with three-dimensional ultrasound, although the difference was not statistically significant. The possibility of rotating a stored volume and inspecting it in three orthogonal planes makes three-dimensional ultrasound a useful tool for nuchal translucency measurements, especially in doubtful cases.

Prenatal diagnosis of partial trisomy 4q26-qter and monosomy for the Wolf-Hirschhorn critical region in a fetus with split hand malformation.

We describe the results of prenatal analyses and postnatal findings in a male fetus with a partial trisomy for the long arm and a small terminal monosomy for the short arm of chromosome 4 with the following karyotype: 46,XY,add(4)(p16.3).ish dup(4)(q26qter)(wcp4+, D4S2336x3,AFMb280xa5x2,4ptel-,WHCR-). G-banding did not identify the origin of the additional chromosomal segment, but this was achieved prenatally by application of RxFISH and whole chromosome painting probes. Subsequent FISH analysis with region-specific YAC clones was used to relate the phenotypic findings such as bilateral split hand formation, specific cardiac and kidney anomalies, microtia, and hypoplastic thorax more exactly to the partial trisomy of the segment 4q26-qter.

Porcelain laminate veneers. A retrospective evaluation after 1 to 10 years of service: Part II--Clinical results.

PURPOSE: The objective of this study was to evaluate the clinical quality of 191 porcelain laminate veneers and to explore the gingival response in a long-term survey. MATERIALS AND METHODS: The clinical examination was made by two calibrated examiners following modified California Dental Association/Ryge criteria. In addition, margin index, papillary bleeding index, sulcus probing depth, and increase in gingival recession were recorded. Two age groups were formed to evaluate the influence of wearing time upon the clinical results. The results were statistically evaluated using the Kaplan-Meier survival estimation method, Chi-squared test, and Kruskal-Wallis test. RESULTS: A failure rate of 4% was found. Six of the total of seven failures were seen when veneers were partially bonded to dentin. Marginal integrity was acceptable in 99% and was rated as excellent in 63%. Superficial marginal discoloration was present in 17%. Slight marginal recession was detected in 31%, and bleeding on probing was found in 25%. CONCLUSION: Porcelain laminate veneers offer a predictable and successful treatment modality that preserves a maximum of sound tooth structure. An increased risk of failure is present only when veneers are partially bonded to dentin. The estimated survival probability over a period of 10 years is 91%.

Investigation of the orientation of purple membrane sheets in Langmuir-Blodgett films by a quartz crystal microbalance.

By means of the quartz crystal microbalance (QCM), a convenient method was developed to determine the degree of orientation of purple membrane (PM) sheets on the air/water interface. Langmuir-Blodgett films from both wild-type and SH-mutant PM (bR D36C) were vertically deposited on the surface of gold-sputtered AT-cut quartz crystals. The shift of resonance frequency of the QCM during a special washing protocol allowed us to differentiate between physically adsorbed PM fragments and any PM attached to the gold surface via chemical bonds. By washing with organic solvents, complete desorption of the wild-type PM was achieved, whereas for the SH-mutant, approximately 60% of the PM fragments could not be detached from the surface. These PM sheets should be oriented with the cytoplasmic side facing the water subphase to that their SH-groups can chemically bind to the gold surface of the quartz plate.

The relationship between peak velocity in the fetal descending aorta and hematocrit in rhesus isoimmunization.

OBJECTIVE: To correlate the peak velocity in the fetal descending aorta, as measured by pulsed Doppler ultrasound, with fetal hematocrit values assessed by funipuncture in pregnancies complicated by rhesus isoimmunization. METHODS: One hundred twelve consecutive funipunctures were performed on 33 rhesus-negative gravidas of 21-36 weeks' gestation (median 30). Doppler flow, corrected for angle, was measured on the fetal descending aorta with pulsed Doppler equipment immediately before funipuncture. Differences between observed peak velocities and the calculated gestational age-dependent upper confidence limits (delta peak velocities) were compared with corresponding differences between observed hematocrits and the calculated lower confidence limits (delta hematocrits), and a regression analysis on the above paired difference values was performed. In addition, the correlation coefficient between delta peak velocities and delta hematocrits was calculated for the first procedure per pregnancy only. RESULTS: The mean peak aortic velocity of anemic fetuses was higher than that of unaffected fetuses (P < .001); delta peak aortic velocities correlated negatively with delta hematocrits (r = -0.66, P < .001). The correlation coefficient between delta peak aortic velocities and delta hematocrits for the first procedure peer pregnancy only was r = -0.72 (P < .001). Prediction of fetal anemia by Doppler using gestational age-dependent 95% confidence limits was possible with positive and negative predictive values of 73 and 66%, respectively. CONCLUSION: Peak aortic velocity, a noninvasive assessment of fetal anemia, may be used as an additional test for monitoring pregnancies complicated by rhesus isoimmunization. However, the limited predictive capacity hampers its clinical usefulness.

[Monitoring umbilical cord puncture and intravascular transfusions with Doppler ultrasound]. / Uberwachung von Nabelschnurpunktionen und intravaskulären Transfusionen mittels Dopplersonographie.

Complications of percutaneous umbilical blood samplings and intravascular transfusions can be detected rapidly, easily and efficiently by Doppler ultrasound and therefore the operator can react as early as possible. In addition to real-time sonography Doppler ultrasound allows for assessment of haemodynamical changes due to intravascular transfusions both on the venous and arterial side of umbilical perfusion. Because of immediate recognition of bradycardia and other fetal cardiac frequency alterations as well as increase of resistance to blood flow on the arterial side the operator can react promptly. On the venous side correct application of transfused volume is monitored continuously by changes of flow velocity waveforms during injection and allows to assess dislocation of the needle.

High-frequency toneburst-evoked ABR latency-intensity functions in sensorineural hearing-impaired humans.

The latency-intensity functions (LIFs) of ABRs elicited by high-frequency (8, 10, 12, and 14 kHz) toneburst stimuli were evaluated in 20 subjects with confirmed 'moderate' high-frequency sensorineural hearing loss. Wave V results from clicks and tonebursts revealed all intra- and intersession data to be reliable (p > 0.05). Linear regression curves were highly significant (p < or = 0.0001), indicating linear relationships for all stimuli analyzed. Comparisons between the linear regression curves from a previously reported normal-hearing subject group and this sensorineural hearing-impaired group showed no significant differences. This study demonstrated that tonebursts at 8, 10, and 12 kHz evoked ABRs which decreased in latency as a function of increasing intensity and that these LIFs were consistent and orderly (14 kHz was not determinable). These results will contribute information to facilitate the establishment of change criteria used to predict change in hearing during treatment with ototoxic medications.

Three-dimensional ultrasound in obstetrics and gynaecology: technique, possibilities and limitations.

Three-dimensional (3D) ultrasound offers several options extending conventional two-dimensional scanning. Various imaging modes are available. Three perpendicular planes displayed simultaneously can be rotated and translated in order to obtain accurate sections and suitable views needed for diagnosis and geometric measurements. 3D ultrasound tomography combines the advantages of ultrasound, e.g. safety, simplicity of application and inexpensiveness, with the advantages of sequentially depictable sections in numerous rotatable and translatable sections. Surface rendering gives detailed plastic images if there are surrounding layers of different echogenicity allowing for the definition of a certain threshold. Transparent modes provide an imaging of structures with a higher echogenicity in the interior of the object. A combination of the two modes sequentially definable by the sonographer allows for the optimal viewing of structures. These imaging modes are innovative features which have to be evaluated for clinical applicability and usefulness. Digital documentation of whole volumes enables full evaluation without loss of information at a later point. 3D technology provides an enormous number of technical options which have to be evaluated for their diagnostic significance and limitations in obstetrics and gynaecology.

High-frequency monitoring for early detection of cisplatin ototoxicity.

Cisplatin can cause irreversible hearing loss initially detectable as impairment of high-frequency hearing with progression to lower frequencies. Many patients receiving cisplatin are too ill to tolerate lengthy audiometric testing. Therefore, a rapid and sensitive high-frequency monitoring strategy to detect cisplatin-induced ototoxicity is needed. Serial conventional (0.25 to 8 kHz) and high-frequency (> or = 8 kHz) threshold monitoring was performed in patients receiving cisplatin, resulting in 84% of ears showing hearing loss, of which 71% were detected first in frequencies of 8 kHz or greater. By analysis according to an individualized, specific high-frequency range, early identification of hearing loss occurred in 94% of ears showing change. This five-frequency procedure is a sensitive detector of ototoxicity and is proposed as an alternative monitoring protocol for patients receiving cisplatin who cannot tolerate extended testing.

[Is there an intermittent HELLP syndrome?]. / Gibt es ein intermittierendes HELLP-Syndrom?

A case of an HELLP-syndrome in the 32nd week of gestation with complete remission of pathological biochemical data and clinical symptomatic within five days is reported. Twenty days later a Caesarean section because of severe fetal growth retardation was performed. Because of this case it has to be discussed, if an "intermittent" HELLP-syndrome does really exist?

High-frequency testing techniques and instrumentation for early detection of ototoxicity.

Veteran patients with certain types of infections and cancers are routinely treated with therapeutic agents having ototoxic potential, thus threatening loss of hearing sensitivity which preexists in the majority of these patients. To prevent communication deficits requiring intervention, this laboratory is developing instrumentation and techniques for early detection of ototoxicity. For this study, conventional (< or = 8 kHz) and high-frequency (> or = 8 kHz) hearing thresholds were monitored behaviorally in hospitalized veterans receiving treatment with ototoxic drugs. Data analysis revealed that monitoring only the high-frequency range would have identified 67% of ears showing change. A five-frequency range of hearing, specific to each individual, was identified for its high sensitivity to early ototoxic change. Monitoring of only these five frequencies in each patient would have identified 82% of ears that showed behavioral change. Auditory brainstem responses (ABR) were obtained in a subgroup using clicks and high-frequency (8-14 kHz) tone bursts. ABR latency/morphology changes were observed in 95% of ears demonstrating behavioral change. High-frequency tone-burst-evoked ABRs alone would have identified 93% of initial changes. Monitoring of high-frequency audition using these techniques shows promise for early detection of ototoxicity with potential for prevention of hearing loss in frequencies essential for verbal communication.

High-frequency tone burst-evoked ABR latency-intensity functions.

High-frequency tone burst stimuli (8, 10, 12, and 14 kHz) have been developed and demonstrated to provide reliable and valid auditory brainstem responses (ABRs) in normal-hearing subjects. In this study, latency-intensity functions (LIFs) were determined using these stimuli in 14 normal-hearing individuals. Significant shifts in response latency occurred as a function of stimulus intensity for all tone burst frequencies. For each 10 dB shift in intensity, latency shifts for waves I and V were statistically significant except for one isolated instance. LIF slopes were comparable between frequencies, ranging from 0.020 to 0.030 msec/dB. These normal LIFs for high-frequency tone burst-evoked ABRs suggest the degree of response latency change that might be expected from, for example, progressive hearing loss due to ototoxic insult, although these phenomena may not be directly related.

Early detection of ototoxicity using high-frequency, tone-burst-evoked auditory brainstem responses.

Subjects receiving treatment with ototoxic agents were evaluated concurrently with conventional and high-frequency (> or = 8 kHz) behavioral threshold measures and with ABR to click and to 8, 10, 12, and 14 kHz tone-burst stimuli. Behavioral threshold data revealed ototoxic change in 51 percent of ears evaluated. Of these ears demonstrating behavioral change, 90 percent revealed concurrent ABR changes. If only ABR monitoring with high-frequency tone-burst stimuli had been used, 87 percent of allears showing behavioral change would have been identified. Three fourths of these would have been identified from wave V responses, with 87 percent identified from the two highest frequencies tested for each individual. This research suggests that behavioral change is reflected accurately in the ABR, that high-frequency tone bursts will identify a majority of initial ototoxic changes, and that monitoring hearing with high-frequency, tone-burst-evoked ABRs during treatment with potentially ototoxic agents is significantly more effective than click-evoked ABRs for early detection of ototoxicity.

High-frequency audiometric monitoring for early detection of aminoglycoside ototoxicity.

Treatment with aminoglycosides is known to cause irreversible hearing loss, typically affecting higher-frequency hearing first and progressing to lower frequencies. Standardized methodology has not been developed for early detection of ototoxicity. Serial conventional (0.25-8 kHz) and high-frequency (9-20 kHz) hearing threshold monitoring was done prospectively in 53 hospitalized patients administered aminoglycosides. Hearing loss occurred in 47% of the ears studied, with hearing loss first appearing in the high-frequency range in 71% of ears showing change. Analysis of data on an individual basis revealed a five-frequency range most susceptible to initial ototoxicity. Testing only this range would have resulted in early identification of 82% of ears showing change. Results confirm the critical need for serial auditory threshold monitoring encompassing high frequencies in patients receiving aminoglycosides. A shortened five-frequency monitoring protocol is presented and suggested for use with patients unable to tolerate lengthy audiometric testing procedures.

Survey of computerized obstetric information systems in Austria.

The aim of this study was to evaluate obstetric electronic data processing (EDP) in Austria and to analyse its problems, advantages and acceptance in a single big obstetric department. We sent questionnaires to every obstetric department in the country. The overall response rate was 77% (73 departments). Only 24 (33%) were using computer aided documentation, but these covered 63% of deliveries in Austria. The proportionate times spent on documentation were 57% for physicians and 43% for midwives, with physicians playing a bigger role in larger departments using electronic documentation. Sixty-five percent of physicians and 31% of midwives readily accepted computerization. We also studied an obstetric department with over 3000 births per year. Twenty-five percent of the medical staff did not believe that computerization saved time, although they appreciated its value to administration and for producing printouts. Advantages in completeness (92%) and accuracy (76%) were recognized. After 6 month's use acceptance of EDP documentation improved significantly.

[Comparison of biochemical and Doppler sonographic monitoring of high-risk pregnancies]. / Vergleich biochemischer und dopplersonographischer Uberwachung von Risikoschwangerschaften.

We performed in 113 patients at least three simultaneous determinations of serum-HPL and oestriol in 24-hour urine samples, as well as Doppler flow studies at the arcuate artery (AA), umbilical artery (UA), foetal aorta and internal carotid, because of suspicion of IUGR. The diagnostic value was studied with regard to IUGR, placental weight and mode of delivery. Concerning the detection of IUGR, the superiority of Doppler parameters (AA, UA) is shown. In the total number of patients, the rates for sensitivity and specificity for UA (78/91%) and AA (58/89%) exceed the hormone parameters. Oestriol, in particular, (13/63%) shows a marked difference, but even HPL (37/63%) cannot compete with respect to diagnostic value.