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1.
Hum Reprod ; 29(2): 201-7, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24287820

ABSTRACT

STUDY QUESTION: Can reliable size charts of human embryonic brain structures be created from three-dimensional ultrasound (3D-US) visualizations? SUMMARY ANSWER: Reliable size charts of human embryonic brain structures can be created from high-quality images. WHAT IS KNOWN ALREADY: Previous studies on the visualization of both the cavities and the walls of the brain compartments were performed using 2D-US, 3D-US or invasive intrauterine sonography. However, the walls of the diencephalon, mesencephalon and telencephalon have not been measured non-invasively before. Last-decade improvements in transvaginal ultrasound techniques allow a better visualization and offer the tools to measure these human embryonic brain structures with precision. STUDY DESIGN, SIZE, DURATION: This study is embedded in a prospective periconceptional cohort study. A total of 141 pregnancies were included before the sixth week of gestation and were monitored until delivery to assess complications and adverse outcomes. PARTICIPANTS/MATERIALS, SETTING, METHODS: For the analysis of embryonic growth, 596 3D-US scans encompassing the entire embryo were obtained from 106 singleton non-malformed live birth pregnancies between 7(+0) and 12(+6) weeks' gestational age (GA). Using 4D View (3D software) the measured embryonic brain structures comprised thickness of the diencephalon, mesencephalon and telencephalon, and the total diameter of the diencephalon and mesencephalon. MAIN RESULTS AND THE ROLE OF CHANCE: Of 596 3D scans, 161 (27%) high-quality scans of 79 pregnancies were eligible for analysis. The reliability of all embryonic brain structure measurements, based on the intra-class correlation coefficients (ICCs) (all above 0.98), was excellent. Bland-Altman plots showed moderate agreement for measurements of the telencephalon, but for all other measurements the agreement was good. Size charts were constructed according to crown-rump length (CRL). LIMITATIONS, REASONS FOR CAUTION: The percentage of high-quality scans suitable for analysis of these brain structures was low (27%). WIDER IMPLICATIONS OF THE FINDINGS:  The size charts of human embryonic brain structures can be used to study normal and abnormal development of brain development in future. Also, the effects of periconceptional maternal exposures, such as folic acid supplement use and smoking, on human embryonic brain development can be a topic of future research. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the Department of Obstetrics and Gynaecology of the Erasmus University Medical Center. M.G. was supported by an additional grant from the Sophia Foundation for Medical Research (SSWO grant number 644). No competing interests are declared.


Subject(s)
Brain/embryology , Organ Size , Pregnancy Trimester, First , Adult , Brain/pathology , Crown-Rump Length , Female , Gestational Age , Humans , Imaging, Three-Dimensional , Male , Multivariate Analysis , Pregnancy , Prospective Studies , Reference Values , Reproducibility of Results , Ultrasonography, Prenatal
4.
Urology ; 54(1): 97-104, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10414734

ABSTRACT

OBJECTIVES: To determine the feasibility of contrast-enhanced three-dimensional (3D) imaging of the prostatic vasculature using power Doppler imaging and to analyze whether semiquantitative judgments of 3D images with respect to symmetry and distribution of vascular structures correlated with biopsy outcome. METHODS: 3D power Doppler images were obtained before and after intravenous administration of 2.5 g Levovist. Subsequently, random and/or directed transrectal ultrasound (TRUS)-guided biopsies were performed. Vascular images were analyzed by two experts. Prostate vasculature was judged with respect to symmetry and vessel distribution using a (scale) grading system. RESULTS: Eighteen patients with a suspicion of prostate cancer either because of an elevated prostate-specific antigen (greater than 4.0 ng/mL; Tandem-R-assay) or an abnormal digital rectal examination were included in the study. Prostate cancer was detected in 13 patients. Vascular anatomy was judged abnormal in unenhanced images in 6 cases, of which 5 proved malignant. Enhanced images were considered suspicious for malignancy in 12 cases, including 1 benign and 11 malignant biopsy results. Sensitivity of enhanced images was 85% (specificity 80%) compared with 38% for unenhanced images (specificity 80%) and 77% for conventional gray-scale TRUS (specificity 60%). Of 6 patients who showed no B-mode abnormalities, vascular patterns were judged abnormal in 4 cases, of which 3 were malignant. CONCLUSIONS: Contrast-enhanced 3D power Doppler angiography is feasible in patients with suspicion of prostate cancer who are scheduled for prostate biopsies. The sensitivity of power Doppler 3D imaging for the detection of prostate malignancy increased from 38% (5 of 13) to 85% (11 of 13) after administration of intravascular microbubble contrast (Levovist), and specificity was found to be 80% (4 of 5) for both imaging modalities. Thus, the use of Levovist when combined with the power Doppler display mode and 3D image reconstruction offers a promising new research area that might prove useful in prostate cancer detection in the future.


Subject(s)
Angiography , Prostatic Neoplasms/diagnosis , Ultrasonography, Doppler, Color , Biopsy , Contrast Media , Humans , Male , Polysaccharides , Sensitivity and Specificity
5.
Behav Brain Res ; 2(3): 347-62, 1981 May.
Article in English | MEDLINE | ID: mdl-7225223

ABSTRACT

Two experiments were carried out to investigate the contribution of gonadal hormones to the expression of sex differences in open field behaviour of adult female and male rats. In the first experiment rats were gonadectomized or sham-operated in adulthood and tested in the open field 1, 2, 3, 4, 5 or 6 weeks later (3 min/rat on 3 consecutive days during the light period of the day). It was found that following gonadectomy the well known sex difference in ambulation and rearing behaviour (females more than males), as well as in defaecation (females less than males) remained. Ovariectomy caused a decrease in ambulation and rearing, with an increase in defaecation, whereas castration had no significant effect on ambulation and rearing, but also increased defaecation. Also an overall increase in ambulation and rearing was found: animals tested 5 and 6 weeks following the operation were significantly more active than animals tested at 1-4 weeks after the operation. In the second experiment female and male rats were gonadectomized and 7 weeks later they received a silastic implant containing testosterone (T), dihydrotestosterone (DHT), oestradiol (E2), DHT plus E2, or nothing (control condition). Four weeks after the implantation the animals were tested in the open field (3 min/rat on 3 consecutive days). An overall sex difference was found for ambulation (females more than males) and for defaecation (females less than males). The only effect of hormone administration was found in DHT-treated animals: lowest ambulation and highest defaecation compared to other hormone and control animals. No differences were found between the T, E2, DHT plus E2, and control animals. From these data it was concluded that endogenous gonadal steroids seem to play a minor role in the expression of sex differences in adult open field behaviour in the rat.


Subject(s)
Behavior, Animal/physiology , Gonadal Steroid Hormones/physiology , Sex Characteristics , Animals , Behavior, Animal/drug effects , Castration , Dihydrotestosterone/pharmacology , Estradiol/pharmacology , Exploratory Behavior/physiology , Female , Male , Motor Activity/physiology , Rats , Testosterone/pharmacology
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