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1.
Facts Views Vis Obgyn ; 14(2): 155-161, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35781112

RESUMO

Objective: To investigate the effect of tadalafil (a long working phosphodiesterase type 5 inhibitor) on the endometrial thickness, biochemical pregnancy rates and clinical pregnancy rates in women in an in vitro fertilization treatment. This study investigates the use of vaginal and oral administration of tadalafil. Study design: This is a prospective double-blind placebo-controlled randomized controlled trial with 58 patients in an in vitro fertilization treatment with a short antagonist stimulation protocol. The study population is divided into three equal groups comparing oral and vaginal administration of tadalafil to a control group. Results: No significant difference in endometrial thickness and number of biochemical and clinical pregnancies was found between the three groups. Conclusion: This study could not show a significant benefit of administration of tadalafil. However, a trend towards more pregnancies in the group treated with oral tadalafil is seen, more research in specific subgroups is needed.

2.
Facts Views Vis Obgyn ; 12(4): 319-323, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33575682

RESUMO

A large tumour mass was detected in a 65-year-old patient during a routine gynaecological examination. This patient had been treated for over 10 years with levothyroxine for Hashimoto's thyroiditis and was also given transdermal oestrogen replacement therapy. Before the operation, detailed imaging by CT scan and MRI was performed. A tumour weighing 1.056 grams and measuring 23x12x7 cm was successfully removed through laparotomy. Histopathology revealed the diagnosis of an extra-uterine, so-called parasitic leiomyoma. Post-surgery recovery was uneventful, but Tibolone treatment was indicated due to disturbing menopausal complaints.

3.
Facts Views Vis Obgyn ; 12(1): 23-30, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32696021

RESUMO

BACKGROUND: It is hypothesized that oxidative and epigenetic alterations to DNA induced by ovarian stimulation for in vitro fertilization (IVF) may be associated with an increased risk of diseases and cancer in the offspring and could possibly be attenuated by preconception food supplementation. METHODS: In a prospective randomised open-label trial, 62 patients were randomly assigned to either 30 days of preconception treatment with the nutraceutical Fertility woman ® duo (Nutriphyt, Beernem, Belgium) (group 1), this nutraceutical complemented with selenomethionine (group 2), or folic acid only (group 3). Biochemical and epigenetic effects and pregnancy rates were assessed. RESULTS: In all 3 groups the level of DNA oxidative damage, estimated by the concentration of 8-hydroxy- 2-deoxyguanosine over creatinine in early morning urine, and the concentration of homocysteine in the blood decreased after treatment. In group 2, the degree of methylation of the cancer-associated CpG2 dinucleotide of the human Telomerase Reverse Transcriptase (hTERT) promoter region, assessed by pyrosequence in follicular cells obtained at oocyte pick-up, was 18% lower than that of group 3. The pregnancy rate, including the transfer of fresh and frozen embryos, was significantly higher in group 2 (50%) than in group 3 (6%) with the result in group 1 being intermediate (30%). CONCLUSION: The results suggest that preconception food supplementation using a specific nutraceutical significantly reduces oxidative and epigenetic DNA changes to follicular cells of women treated by IVF, and may optimize gene expression in the oocytes, thus increasing the pregnancy rate per cycle of ovarian stimulation.

4.
J Assist Reprod Genet ; 36(10): 2007-2016, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31463872

RESUMO

INTRODUCTION: Belgian legislation allows only strictly anonymous gamete donation and known donation (donation to a recipient known by the donor). Recently, an amendment of the legislation was proposed to grant donor offspring, as of 18 years old, the right to claim identifying information about their donor. PURPOSE: The aim is to explore the attitude of actual sperm donors towards donation and the release of identifying information and to investigate which donors would be willing to donate when anonymity would be prohibited by law. METHODS: All men who were accepted as sperm donors (n = 242) by AZ Jan Palfijn Hospital (Ghent, Belgium) were invited to complete an anonymous online survey. The response rate was 65.5%. RESULTS: One in five (20.1%; n = 30) would continue sperm donation upon a legislation change towards identifiable donation. Three in four donors (75.2%) would agree to provide basic non-identifiable information about themselves and one in three (32.9%) would provide extra non-identifiable information such as a baby photo or a personal letter. Almost half of the donors (45.6%) would agree to donate in a system where the hospital can trace the donor at the child's request and contact the donor, leaving it to the donor to decide whether or not to have contact with the requesting donor child. CONCLUSION: These findings show that only one in five current donors would continue to donate when identifiable. The study also demonstrates that current donors think more positive about alternative options and that nearly half of them are willing to be contacted by the hospital at the donor child's request, providing the donor can decide at that time whether or not to release his identity.


Assuntos
Espermatozoides/transplante , Doadores de Tecidos/psicologia , Obtenção de Tecidos e Órgãos , Adolescente , Adulto , Atitude , Família/psicologia , Humanos , Masculino , Inquéritos e Questionários , Doadores de Tecidos/legislação & jurisprudência
5.
Med Hypotheses ; 117: 50-53, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30077197

RESUMO

The present paper reports the results of a pragmatic prospective trial in a group of 38 random infertile couples in whom a battery of semen assays were performed before in vitro fertilisation (IVF). Sixteen couples (42.1%) attained ongoing pregnancy. Using logistic regression analysis only the result of the Oxisperm® (P = 0.047) and the HaloSperm G2® for DNA fragmentation (P < 0.0001) were significantly associated with the occurrence of pregnancy, whereas neither the conventional semen characteristics, nor the outcome of multiple other tests were significantly related (P > 0.05). Based on the logistic regression analysis the following formula could be derived: Logit(p) = 6.15-0.407 × (% halotest), whereby (p) is the probability of pregnancy, and % halotest is the proportion of spermatozoa showing DNA fragmentation in the HaloSperm G2® test. Receiver operating characteristic curve analysis revealed an area under the curve (AUC) of 0.83. In 16 out of 38 couples the IVF outcome, either positive or negative, could unequivocally be predicted, while in the remaining cases the probability of pregnancy was significantly related to the result of the formula. These findings confirm the hypothesis that sperm DNA-fragmentation largely determines the success of IVF.


Assuntos
Fragmentação do DNA , Fertilização in vitro/métodos , Análise do Sêmen/métodos , Espermatozoides/fisiologia , Adulto , Área Sob a Curva , DNA/análise , Feminino , Humanos , Masculino , Modelos Teóricos , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Curva ROC , Espécies Reativas de Oxigênio/metabolismo , Análise de Regressão , Adulto Jovem
6.
Hum Reprod ; 31(9): 2017-23, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27370359

RESUMO

STUDY QUESTION: Does a 3-month adjuvant hormonal treatment of mild peritoneal endometriosis after laparoscopic surgery influence the outcome of IVF stimulation in terms of number of mature oocytes obtained per cycle? SUMMARY ANSWER: Complementary medical treatment of mild peritoneal endometriosis does not influence the number of oocytes per treatment cycle. WHAT IS KNOWN ALREADY: Endometriosis is a disease known to be related to infertility. However, the influence of superficial endometriosis-and its treatment-is still a matter of debate. STUDY DESIGN, SIZE, DURATION: A prospective controlled, randomized, open label trial was performed between February 2012 and March 2014 and embryological and clinical outcomes were measured. Patients with laparoscopically diagnosed peritoneal endometriosis (n= 120) were treated by laser surgery after which they were sequentially randomized by computer-generated allocation to one of the two groups. The primary outcome of the trial was the number of Metaphase II (MII) oocytes. Sample size was chosen to detect a difference of two MII oocytes with a power of 80%. The control group (Group B) received the classical long protocol IVF stimulation, whereas the research group (Group A) had an additional pituitary suppression, of 3 months using a long-acting GnRH agonist, prior to IVF. PARTICIPANTS/ MATERIALS, SETTING, METHODS: A total of 120 patients were included in the study, 61 of them in the study group and 59 patients in the control group. One patient of the control group was lost to follow up leading to 58 evaluable patients. MAIN RESULTS AND THE ROLE OF CHANCE: There was no difference in terms of the number of MII oocytes obtained per cycle: 8.2 in both groups (difference in MII between A and B: 0.07 [-1.89; 2.04] 95% confidence interval (CI)). Pregnancy rate did not differ, being 39.3% for Group A (24 out of 61 patients) versus 39.7% for Group B (23 out of 58 patients) (95% CI around difference in pregnancy rate between A and B: -0.31% [-17.96%; 17.86%]). However, a significantly (P = 0.025) lower dose of FSH (2561 IU for Group A and 2303 IU for Group B, 95% CI around difference in FSH between B and A: -258.6 IU [-483.4 IU; -33.8 IU]) and a significantly (P = 0.004) shorter stimulation period (Group A 12.3 days and Group B 11.3 days, 95% CI around difference in stimulation period between B and A: -1.03 days [-1.73 days; -0.33 days]) were needed to reach adequate follicle maturation in the control group. LIMITATIONS, REASON FOR CAUTION: The validity of this study is limited to mild peritoneal endometriosis, and does not apply to ovarian endometriosis, which is also commonly seen in infertility patients. WIDER IMPLICATIONS OF THE FINDINGS: There is no indication for complementary medical treatment of peritoneal endometriosis in terms of IVF outcome. On the contrary, stimulation takes longer and requires a higher amount of medication. STUDY FUNDING/COMPETING INTERESTS: There was no external funding for this clinical trial in the IVF Center, AZ Jan Palfijn, Ghent. There are no competing interests to declare. TRIAL REGISTRATION NUMBER: EudraCT nr: 2012-000784-25. TRIAL REGISTRATION DATE: First registration on 29 February 2012 and re-entered on 23 August 2012, NCT01682642 (due to a change of staff). DATE OF FIRST PATIENT'S ENROLLMENT: 8 March 2012.


Assuntos
Endometriose/cirurgia , Fertilização in vitro/métodos , Infertilidade Feminina/terapia , Terapia a Laser , Doenças Peritoneais/cirurgia , Adulto , Endometriose/complicações , Feminino , Humanos , Infertilidade Feminina/etiologia , Indução da Ovulação/métodos , Doenças Peritoneais/complicações , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
7.
Facts Views Vis Obgyn ; 7(4): 223-230, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-27729967

RESUMO

OBJECTIVE: To demonstrate the feasibility of scheduling an IVF cycle, without disadvantages, in the new patient friendly stimulation protocol using the long acting Corifollitropin Alfa, in combination with GnRH-antagonist protection and GnRH-agonist triggering. STUDY DESIGN: Two groups of ten patients were admitted in the study. Both received the same stimulation protocol with Corifollitropin Alfa in combination with GnRH-antagonist protection. After ultrasound evaluation on day 7 individually dosed Menopur was added. For triggering final oocyte maturation GnRH-agonists were used. The only difference between the two groups was that in the study group, estradiol valerate 4 mg/day was given from day 25 of the preceding cycle for a period of 10 days, thus postponing the start of follicular growth. RESULTS: Scheduling the IVF stimulation by the administration of estradiol valerate 4 mg/day did not influence the hormonal curves, nor the embryological results in comparison to patients with the same stimulation, starting their stimulation at the beginning of menstruation. In this pilot study four out of ten patients turned out to be pregnant, demonstrating an acceptable pregnancy rate. CONCLUSION: The combination of estradiol valerate 4 mg/day pre-treatment with the novel combination of Corifollitropin Alfa stimulation with GnRH-antagonist protection, individually topped off with Menopur, and triggered with GnRH-agonist proved to be a safe, patient-friendly (limited number of injections in comparison to classical IVF) (Patil, 2014) and efficient alternative to classical IVF stimulation protocols, allowing patients - and doctors - to schedule the treatment cycle to their convenience.

8.
Facts Views Vis Obgyn ; 6(3): 159-65, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25374659

RESUMO

A pilot study of 10 patients undergoing IVF stimulation, using the new combination of Corifollitropin Alfa with highly purified hMG and GnRH antagonists has been performed, whereas final oocyte maturation was induced by GnRH analogues. The hormonal profiles were analyzed, as well as the clinical outcome. All patients were recruited between March 1st 2013 and June 30(th) 2013. They were all younger than 38 years, had a normal BMI (between 18,0 and 32,0) and did not have more than three previous IVF stimulations. The combination of long acting FSH with hphMG, and under protection of GnRH antagonists against spontaneous LH-surge, provided a normal hormonal profile for estradiol, progesterone, LH, and FSH. The average oocyte quality and embryo quality were excellent, which resulted in four pregnancies out of ten. We conclude that the described combination is a safe, efficient, and patient friendly alternative for the classical IVF stimulation.

9.
Facts Views Vis Obgyn ; 6(4): 203-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25593695

RESUMO

A prospective randomized controlled trial comparing two groups of ICSI (intra-cytoplasmatic sperm injection) patients with a different form of triggering the final oocyte maturation has been performed. All patients received an ovarian stimulation for in vitro fertilisation (IVF) using an antagonist protocol using recombinant-FSH -(rec-FSH) and Ganirelix. 120 Patients were randomized into two groups with similar clinical parameters. The first group had triggering with hCG, whereas the second group received a combination of hCG + GnRH agonist (Gonadotropin Releasing Hormone). As the primary endpoint, the number of metaphase II oocytes were analysed, the secondary endpoints were the number of cumulus oocyte complexes (COC), the number of fertilized oocytes, embryo morphology, pregnancy rate and the number of cryopreserved embryos. The mean number of MII oocytes in the hCG triggered group was 9.2 compared with 10.3 in the hCG-GnRH agonist group. There was no statistically significant difference in the number of COCs or pregnancy rates. However, the number of patients who received at least one embryo of excellent quality was significantly higher (p = 0.001) in the group with the combined triggering (45 out of 61 patients or 73.8%) versus the group with hCG triggering alone (28 out of 59 patients or 47.5%). The number of cryopreserved embryos was also higher in this group.

10.
Andrologia ; 44(6): 401-4, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22536793

RESUMO

To compare the clinical efficiency of different modes of treatment of infertile couples and to estimate the possible benefit of nutraceutical food supplementation (NFS), the numbers needed to treat (NNT) was calculated in 4143 infertile couples based on controlled trials in recent literature and personal data. The NNT expresses the number of individuals who need to be treated to obtain one complementary pregnancy. In female infertility, the NNT of mild or moderate endometriosis was 8.4, and in anti-estrogens treatment of anovulation, it was 5.9. In tamoxifen treatment of idiopathic oligozoospermia, NNT was 3.9, and in antioxidant supplementation, it was 7.8. Treatment of varicocele yielded NNT of 6.3 and 6.8 after 1 year in multi- or single-centre trials, respectively, and NFS lowered the NNT after 3 months to 2.6. Adding NFS to the male partner increased the ongoing pregnancy rate by IVF with NNT of 8.3, and adding NFS to both partners reduced the NNT to 4.0. Although these results were obtained in heterogeneous trials and populations, it is suggested that the NNT should be useful for comparing the effectiveness of different modes of treatment of the infertile couple, and that complementary nutraceutical food supplementation may be beneficial.


Assuntos
Suplementos Nutricionais , Infertilidade/dietoterapia , Infertilidade/terapia , Adulto , Anovulação/complicações , Anovulação/tratamento farmacológico , Ensaios Clínicos Controlados como Assunto/estatística & dados numéricos , Endometriose/complicações , Endometriose/terapia , Moduladores de Receptor Estrogênico/uso terapêutico , Feminino , Fertilização in vitro , Humanos , Infertilidade/etiologia , Masculino , Oligospermia/complicações , Oligospermia/tratamento farmacológico , Gravidez , Técnicas de Reprodução Assistida , Tamoxifeno/uso terapêutico , Resultado do Tratamento , Varicocele/complicações , Varicocele/terapia
11.
Facts Views Vis Obgyn ; 4(4): 227-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-24753913

RESUMO

A prospective cohort study has been performed to find out if the administration of an oxytocin antagonist (Atosiban) at the occasion of embryo transfer has an effect on the pregnancy rate in patients with repeated failure of implantation. A total of 52 women with repeated failure of implantation after IVF/ICSI were included in this study. The ongoing pregnancy rate (OPR) in the total group of patients was 12 out of 52 (23.1%). Based on embryo quality all cases were categorized in two groups. One with good embryo quality (Group A) and one with poor quality embryos (Group B). Of all patients who became pregnant, 11 belonged to the group of 26 patients with good quality embryos (OPR 42.3 %) and only one to the group of 26 patients with poor quality embryos (OPR 3.8 %). Our results indicate that when good quality embryos can be obtained, the use of Atosiban at the occasion of embryo transfer might offer a significant better implantation rate in women with repeated implantation failure after IVF/ICSI.

12.
Hum Reprod ; 24(12): 3108-18, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19726447

RESUMO

BACKGROUND: Cross-border reproductive care indicates the cross-border movements made by patients to obtain infertility treatment they cannot obtain at home. The problem at present is that empirical data on the extent of the phenomenon are lacking. This article presents the data on infertility patients going to Belgium for treatment. METHODS: A survey was conducted among the centres for reproductive medicine that are allowed to handle oocytes and create embryos (B-centres). Data were collected on the nationality of patients and the type of treatment for which they attended during the period 2000-2007. RESULTS: Sixteen of 18 centres responded to the questionnaire. The flow of foreign patients has stabilized since 2006 at approximately 2100 patients per year. The majority of foreign nationals seeking treatment in Belgium were French women for sperm donation. The next highest group was patients entering the country to obtain ICSI with ejaculated sperm. CONCLUSIONS: There are clear indications that numerous movements are motivated by the wish to evade legal restrictions in one's home country, either because the technology is prohibited or because the patients have characteristics, which exclude them from treatment in their own countries.


Assuntos
Infertilidade/terapia , Turismo Médico/estatística & dados numéricos , Serviços de Saúde Reprodutiva/estatística & dados numéricos , Técnicas de Reprodução Assistida/estatística & dados numéricos , Adulto , Bélgica , Feminino , França/etnologia , Pesquisas sobre Atenção à Saúde , Humanos , Inseminação Artificial Heteróloga/estatística & dados numéricos , Masculino , Turismo Médico/tendências , Pessoa de Meia-Idade , Programas Nacionais de Saúde/legislação & jurisprudência , Programas Nacionais de Saúde/estatística & dados numéricos , Países Baixos/etnologia , Seleção de Pacientes , Diagnóstico Pré-Implantação/estatística & dados numéricos , Técnicas de Reprodução Assistida/legislação & jurisprudência , Injeções de Esperma Intracitoplásmicas/estatística & dados numéricos , Adulto Jovem
14.
Fortschr Med ; 110(16): 298-301, 1992 Jun 10.
Artigo em Alemão | MEDLINE | ID: mdl-1634171

RESUMO

In the present paper, a new therapeutic concept of photodynamic laser therapy using antibody-linked dyes for the treatment of gynecological malignancies is described. So far, HPD (hematoporphyrin derivative) has been employed in this area, but is associated with toxic systemic reactions. We see a solution to this problem in the linking of a systemically non-toxic dye--known to induce photodynamic reactions while not itself being selectively accumulated within tumor cells--to an antibody directed against a selective tumor-associated antigen. The results of our study demonstrate the efficacy of this therapeutic concept as exemplified by the selective destruction of dye-labeled ovarian carcinoma cells by laser light of a defined wavelength (675 nm). The potential of this form of photodynamic therapy extends far beyond its use in ovarian carcinoma.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Neoplasias Ovarianas/patologia , Fotoquimioterapia/métodos , Células Tumorais Cultivadas/efeitos dos fármacos , Anticorpos Monoclonais/uso terapêutico , Linhagem Celular , Feminino , Humanos , Imunotoxinas/uso terapêutico , Ensaio Tumoral de Célula-Tronco
15.
Eur J Obstet Gynecol Reprod Biol ; 42 Suppl: S84-6, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1809614

RESUMO

Recent progress in the area of prenatal diagnosis by means of ultrasound forces the improvement of surgical techniques for intra-uterine fetal therapy. By the use of short, intense pulses of ultraviolet laser light (20-200 ns long) a photoablation of defined samples of biological tissue is performed with no substantial thermal side effects. The experimental set-up applied in this study included endoscopic operation on five fetal lambs. Macroscopically, a sharp edge in the incision area was observed at both prechosen laser frequencies of 10 and 40 Hz. The clinical application of pulsed ultraviolet laser systems with the characteristics of guided photoablation and atraumatic incisions avoiding thermal side-effects opens new perspectives for fetal surgery.


Assuntos
Endoscopia , Feto/cirurgia , Terapia a Laser , Animais , Feminino , Gravidez , Ovinos
16.
Klin Padiatr ; 203(2): 77-82, 1991.
Artigo em Alemão | MEDLINE | ID: mdl-2033909

RESUMO

An new method of lung maturation during artificial placentation was evaluated during a series of 15 animal experiments in premature lambs (gestational age 125-132 days). Perfusion circuit with interposition of a membrane lung was connected with the umbilical vessels. Extracorporeal CO2-removal (ECCO2-R) and apneic oxygenation were provided during lung distension. The ultramicroscopic pattern approved a maturation of the lung during the procedure showing development of lamellar bodies and surfactant secretion into the alveolar space. The biochemical analysis of the tracheal fluid showed a significant increase of both PC and PG concentrations (3.225 +/- 1.112 mg/100g to 24.228 +/- 3.36 mg/100 g respectively 0.249 +/- 0.11 mg/100 g of 0.622 +/- 0.09 mg/100 g. The biophysical function of the lung was also improved as was shown by a significant increase of the statistical compliance. We conclude that artificial placentation and lung distension might be a new mode of prophylaxis for respiratory distress syndrome in critically immature babies.


Assuntos
Pulmão/embriologia , Placentação , Animais , Líquidos Corporais/química , Oxigenação por Membrana Extracorpórea , Feminino , Maturidade dos Órgãos Fetais , Pulmão/ultraestrutura , Ácidos Fosfatídicos/análise , Gravidez , Surfactantes Pulmonares/metabolismo , Ovinos , Traqueia/metabolismo
17.
Arch Gynecol Obstet ; 249(1): 9-14, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1892426

RESUMO

Photodynamic therapy (PDT) with laser radiation opens a new field in the treatment of malignancies. We evaluated the phototoxic effects of five different substances for photodynamic therapy in concentrations showing no systemic toxicity. We used gynecologic tumor cells and evaluated the photodynamic effects for cell growth in a colony-forming assay. For Indigocarmin we found a reduction in the colony-forming assay compared to the control group from 87% to 66% after irradiation at 50 mumol/l and 608 nm wavelength. "IR 132" showed a reduction in the colony-forming assay from 73% to 72% 50 mumol/l (590 nm). For the incubation of the HeLa cells with 50 mumol/l of "Sulfo-Phthalocyanin" we found a reduction of the colony-forming potential from 81% to 67% (595 nm). The most strikingly differences were found for the incubation and irradiation of Methylene Blue, showing a reduction from 77% to 16% caused by a toxic effect of the substance itself (5 mumol/l, 660 nm) and "Sulfo-Aluminium-Phthalocyanin" stained cells, which shows a reduction from 86% to 17% (50 mumol/l, 675 nm). We see the possibility of a photoactivation and cell devitalisation by "Sulfo-Aluminium-Phthalocyanin" and laser radiation. A future clinical trial would seem justified.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Fotoquimioterapia/métodos , Radiossensibilizantes/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Ensaio Tumoral de Célula-Tronco , Células HeLa , Humanos , Terapia a Laser , Fotoquimioterapia/instrumentação , Relação Estrutura-Atividade
18.
J Perinat Med ; 19(3): 231-5, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1748947

RESUMO

Fetal malformations are detected early in pregnancy by means of ultrasound challenging fetal therapy. While open fetal surgery has been preformed during preliminary clinical trials we evaluated fetoscopic therapy avoiding laparotomy and uterotomy. We used a laser fibre (900 mu) which was introduced into the uterus by an endoscope. During animal experiments in five fetal lambs with a gestational age of 120-122 days we used an excimer laser (Technolas, x) with a wave-length of 308 nm. Laser incisions were compared with the conventional cutting technique using a scapel. During histological evaluation the tissue effect was morphometricly analysed. The zone of devitalisation was characterized by pycnosis of the nuclei and in a change of cytoplasma volume. The excimer laser incisions using a frequency of 40 HZ had a mean zone of devitalisation of 50.3 +/- 4.5 mu. Using the excimer laser with a frequency of 10 HZ we found a tissue alteration of only 11.2 +/- 3.4 mu. The incisions by scapel showed a extended traumatisation with a mean tissue effect of 153.2 +/- 16.3 mu. From these results we conclude, that endoscopic surgery may be come a usefull additional tool for fetal therapy.


Assuntos
Feto/cirurgia , Terapia a Laser , Animais , Fetoscopia , Complicações Intraoperatórias/prevenção & controle , Terapia a Laser/métodos , Ovinos
19.
Biomed Tech (Berl) ; 35(9): 185-9, 1990 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-2223938

RESUMO

The noninvasive determination of biochemical parameters has become an important aspect of intensive care medicine. The newly developed monitors for laser reflectometry provide the possibility of spectroscopic monitoring. The equipment consists of a near-infrared data collection unit and a personal computer. The four laser diodes emit light at wavelengths of 775, 805, 845 and 904 nm. By analyzing the changes in optical density during laser irradiation of biological tissue, information is obtained about the relative changes in the concentration of hemoglobin and the blood volume. In animal experiments with ten fetal lambs we evaluated the reliability of near infrared laser spectroscopy. Fetal hyperoxia was achieved by means of an extracorporeal circuit with interposition of a membrane oxygenator (0.8 m2, Scimed). During the induced hyperoxia the laser spectroscopic tracings showed a rise in the HbO2 signal with a synchronous decrease in the HbR signal. Additionally, the spectroscopic pattern showed a characteristic initial rise in the intracerebral blood volume, which stabilized after 4 minutes. We found a significant correlation between the intermittently measured PO2 values of the arterial blood samples and the laser spectroscopic HbO2 and HbR signals (r = 0.87, and r = -0.82, respectively; p less than 0.001). Furthermore, hyperoxia was indicated by the laser system with a short lag time. We conclude that laser spectroscopy is a reliable method with a high potential for clinical routine use in intensive care, as it provides noninvasive continuous information at comparatively low costs using portable monitors.


Assuntos
Lasers , Oxigênio/sangue , Ovinos/sangue , Análise Espectral/métodos , Animais , Volume Sanguíneo , Encéfalo/irrigação sanguínea , Oxigenação por Membrana Extracorpórea , Feto , Oxiemoglobinas/análise
20.
Z Geburtshilfe Perinatol ; 194(5): 219-23, 1990.
Artigo em Alemão | MEDLINE | ID: mdl-1701951

RESUMO

In order to evaluate the influence on the fetal brain due to compression of the umbilical cord biochemical and biophysical changes were traced during defined occlusions of 60 sec by means of NIR laser spectroscopy. Synchronously blood samples were drawn intermittently from a catheter positioned in the A. carotis and analysed for blood gases. The saturation values measured in the fetal blood correlated significantly with the dates of the HbO2 tracing of the NIR-system (r = 0.81, p less than 0.001). After induced occlusion of the umbilical cord a reproducible pattern of the NIR tracing occurred. While an immediate fall in HbO2 occurred, a synchronous rise in desaturated Hb was observed. For the changes of the cytochrome aa3 we detected a minor decrease that occurred with a lag time. Additionally there was an indication of a major change of blood volume as the total Hb content augmented during each compression. We concluded: Changes of Hb-saturation in the fetal blood are immediately indicated by NIR-laser spectroscopy. During cord occlusion of 60 sec. the intracellular oxygenation decrease only after a significant lag time and are reversible and furthermore it leads to a reproducible change of intracerebral blood volume.


Assuntos
Química Encefálica , Sangue Fetal/química , Feto/metabolismo , Cordão Umbilical , Animais , Volume Sanguíneo , Circulação Cerebrovascular , Constrição , Complexo IV da Cadeia de Transporte de Elétrons/sangue , Hemoglobina Fetal/análise , Lasers , Oxigênio/sangue , Ovinos , Espectrofotometria Infravermelho
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