Acceptability and feasibility of a planned preconception weight loss intervention in women with long-acting reversible contraception: the Plan-it mixed-methods study

BACKGROUND

Women with overweight (a body mass index of ≥ 25 kg/m²) or obesity (a body mass index of ≥ 30 kg/m²) are at greater risk of experiencing complications during pregnancy and labour than women with a healthy weight. Women who remove their long-acting reversible contraception (i.e. coils or implants) are one of the few groups of people who contact services as part of their preparation for conception, creating an opportunity to offer a weight loss intervention.

OBJECTIVES

The objectives were to understand if routine NHS data captured the pathway from long-acting reversible contraception removal to pregnancy and included body mass index; to identify the suitable components of a preconception weight loss intervention; and to engage with key stakeholders to determine the acceptability and feasibility of asking women with overweight/obesity to delay the removal of their long-acting reversible contraception in order to take part in a preconception weight loss intervention.

DESIGN

This was a preparatory mixed-methods study, assessing the acceptability and feasibility of a potential intervention, using routine NHS data and purposefully collected qualitative data.

PARTICIPANTS

The NHS routine data included all women with a long-acting reversible contraception code. There were three groups of participants in the surveys and interviews: health-care practitioners who remove long-acting reversible contraception; weight management consultants; and women of reproductive age with experience of overweight/obesity and of using long-acting reversible contraception.

SETTING

UK-based health-care practitioners recruited at professional meetings; and weight management consultants and contraceptive users recruited via social media.

DATA SOURCES

Anonymised routine data from UK sexual health clinics and the Clinical Practice Research Datalink, including the Pregnancy Register; and online surveys and qualitative interviews with stakeholders.

RESULTS

The records of 2,632,871 women aged 16-48 years showed that 318,040 had at least one long-acting reversible contraception event, with 62% of records including a body mass index. Given the identified limitations of the routine NHS data sets, it would not be feasible to reliably identify women with overweight/obesity who request a long-acting reversible contraception removal with an intention to become pregnant. Online surveys were completed by 100 health-care practitioners, four weight management consultants and 243 contraceptive users. Ten health-care practitioners and 20 long-acting reversible contraception users completed qualitative interviews. A realist-informed approach generated a hypothesised programme theory. The combination of weight discussions and the delay of long-acting reversible contraception removal was unacceptable as an intervention to contraceptive users for ethical and practical reasons. However, a preconception health intervention incorporating weight loss could be acceptable, and one potential programme is outlined.

LIMITATIONS

There was very limited engagement with weight management consultants, and the sample of participating stakeholders may not be representative.

CONCLUSIONS

An intervention that asks women to delay long-acting reversible contraception removal to participate in a preconception weight loss intervention would be neither feasible nor acceptable. A preconception health programme, including weight management, would be welcomed but requires risk communication training of health-care practitioners.

FUTURE WORK

Work to improve routine data sets, increase awareness of the importance of preconception health and overcome health-care practitioner barriers to discussing weight as part of preconception care is a priority.

TRIAL REGISTRATION

This trial is registered as ISRCTN14733020.

FUNDING

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 27, No. 1.

The acceptability of asking women to delay removal of a long-acting reversible contraceptive to take part in a preconception weight loss programme: a mixed methods study using qualitative and routine data (Plan-it)

Background

Having a body mass index (BMI) which is classified as overweight (BMI ≥ 25) or obese (BMI ≥ 30) increases the risk of complications during pregnancy and labour. Weight-management interventions which target excess gestational weight gain during pregnancy have had limited success. Women who use long-acting reversible contraception (LARC) are in contact with services as part of their preparation for conception, creating a potential opportunity to offer a preconception weight-loss intervention.

The aims of this mixed methods study were to assess the acceptability and practicability of a weight-loss intervention which asked people to delay LARC removal in order to lose weight before conceiving.

Methods

Routine UK NHS data were analysed to identify pathways from LARC removal to pregnancy. Qualitative surveys and advisory group discussions with service providers and LARC users with experience of being overweight were conducted and analysed thematically.

Results

Three hundred fifteen thousand seven hundred fifty-five UK women aged 16–48 years between 2009–2018 had at least one LARC-related event (e.g. insertion, removal) and 1.7% of those events were recorded as related to planning a pregnancy. BMI was included in 62% of women’s records, with 54% of those BMI being classified as overweight or obese. Online surveys were completed by 100 healthcare practitioners and 243 LARC users. Stakeholders identified facilitators and barriers associated with the proposed intervention including sensitivities of discussing weight, service-user past experiences, practitioner skills, the setting and ethical implications of the proposed intervention.

Conclusions

Although women and service providers recognised potential benefits, a preconception weight-loss intervention asking people to delay LARC removal posed many barriers, due mainly to the acceptability of such an intervention to women and healthcare practitioners. Weight-loss interventions that target the general population, together with a focus on improving public knowledge of preconception health, may be more acceptable than interventions which solely focus on LARC users. Many of the barriers identified, including communication, understanding and beliefs about weight and risk, appointment systems and the limitations of routine datasets also have relevance for any preconception weight-loss intervention. Work to improve routine datasets and reducing communication barriers to discussing weight are priorities.

Trial registration

ISRCTN14733020 registered 10.05.2019.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-05077-0.

Characteristics of e-cigarette users and their perceptions of the benefits, harms and risks of e-cigarette use: survey results from a convenience sample in Ottawa, Canada

INTRODUCTION

Although e-cigarette use ("vaping") is increasing in Canada, few attempts have been made to describe e-cigarette users ("vapers"). In this context, we conducted a study in Ottawa, Canada, to describe e-cigarette users' perceptions of the benefits, harms and risks of e-cigarettes. We also collected information on why, how and where they use e-cigarettes as well as information on side effects.

METHODS

A 24-item online survey was administered to individuals who purchased e-cigarettes or e-cigarette-related supplies at one of Ottawa's 17 e-cigarette shops. Descriptive analyses characterized respondents, and logistic regression models were fitted to evaluate the relationship between respondents' characteristics and their perception of e-cigarette harms.

RESULTS

The mean age of the 242 respondents was 38.1 years (range: 16-70 years); 66% were male. Nearly all had smoked 100 or more cigarettes in their lifetime (97.9%). More than 80% indicated that quitting smoking was a very important reason for starting to use e-cigarettes and 60% indicated that they intend to stop using e-cigarettes at some point. About 40% reported experiencing some side effects within 2 hours of using e-cigarettes. Those who did not report experiencing any of the listed side effects had approximately 3.2 times higher odds of perceiving e-cigarettes as harmless than those who reported having side effects (odds ratio = 3.17; 95% confidence interval: 1.75-5.73).

CONCLUSION

Our findings suggest that most e-cigarette users are using them to reduce or stop smoking cigarettes and perceive them as harmless. Due to our use of convenience sampling, the reader should be cautious in generalizing our findings to all Canadian e-cigarette users.

FoxP1 marks medium spiny neurons from precursors to maturity and is required for their differentiation

Identifying the steps involved in striatal development is important both for understanding the striatum in health and disease, and for generating protocols to differentiate striatal neurons for regenerative medicine. The most prominent neuronal subtype in the adult striatum is the medium spiny projection neuron (MSN), which constitutes more than 85% of all striatal neurons and classically expresses DARPP-32. Through a microarray study of genes expressed in the whole ganglionic eminence (WGE: the developing striatum) in the mouse, we identified the gene encoding the transcription factor Forkhead box protein P1 (FoxP1) as the most highly up-regulated gene, thus providing unbiased evidence for the association of FoxP1 with MSN development. We also describe the expression of FoxP1 in the human fetal brain over equivalent gestational stages. FoxP1 expression persisted through into adulthood in the mouse brain, where it co-localised with all striatal DARPP-32 positive projection neurons and a small population of DARPP-32 negative cells. There was no co-localisation of FoxP1 with any interneuron markers. FoxP1 was detectable in primary fetal striatal cells following dissection, culture, and transplantation into the adult lesioned striatum, demonstrating its utility as an MSN marker for transplantation studies. Furthermore, DARPP-32 expression was absent from FoxP1 knock-out mouse WGE differentiated in vitro, suggesting that FoxP1 is important for the development of DARPP-32-positive MSNs. In summary, we show that FoxP1 labels MSN precursors prior to the expression of DARPP-32 during normal development, and in addition suggest that FoxP1 labels a sub-population of MSNs that are not co-labelled by DARPP-32. We demonstrate the utility of FoxP1 to label MSNs in vitro and following neural transplantation, and show that FoxP1 is required for DARPP-32 positive MSN differentiation in vitro.

Fetal calcium regulates branching morphogenesis in the developing human and mouse lung: involvement of voltage-gated calcium channels

Airway branching morphogenesis in utero is essential for optimal postnatal lung function. In the fetus, branching morphogenesis occurs during the pseudoglandular stage (weeks 9–17 of human gestation, embryonic days (E)11.5–16.5 in mouse) in a hypercalcaemic environment (∼1.7 in the fetus vs. ∼1.1–1.3 mM for an adult). Previously we have shown that fetal hypercalcemia exerts an inhibitory brake on branching morphogenesis via the calcium-sensing receptor. In addition, earlier studies have shown that nifedipine, a selective blocker of L-type voltage-gated Ca²⁺ channels (VGCC), inhibits fetal lung growth, suggesting a role for VGCC in lung development. The aim of this work was to investigate the expression of VGCC in the pseudoglandular human and mouse lung, and their role in branching morphogenesis. Expression of L-type (Ca_V1.2 and Ca_V1.3), P/Q type (Ca_V2.1), N-type (Ca_V2.2), R-type (Ca_V2.3), and T-type (Ca_V3.2 and Ca_V3.3) VGCC was investigated in paraffin sections from week 9 human fetal lungs and E12.5 mouse embryos. Here we show, for the first time, that Ca_v1.2 and Ca_v1.3 are expressed in both the smooth muscle and epithelium of the developing human and mouse lung. Additionally, Ca_v2.3 was expressed in the lung epithelium of both species. Incubating E12.5 mouse lung rudiments in the presence of nifedipine doubled the amount of branching, an effect which was partly mimicked by the Ca_v2.3 inhibitor, SNX-482. Direct measurements of changes in epithelial cell membrane potential, using the voltage-sensitive fluorescent dye DiSBAC₂(3), demonstrated that cyclic depolarisations occur within the developing epithelium and coincide with rhythmic occlusions of the lumen, driven by the naturally occurring airway peristalsis. We conclude that VGCC are expressed and functional in the fetal human and mouse lung, where they play a role in branching morphogenesis. Furthermore, rhythmic epithelial depolarisations evoked by airway peristalsis would allow for branching to match growth and distension within the developing lung.

Feasibility study of patient positioning verification in electron beam radiotherapy with an electronic portal imaging device (EPID)

The purpose of this study is to demonstrate the feasibility of verification and documentation in electron beam radiotherapy using the photon contamination detected with an electronic portal imaging device. For investigation of electron beam verification with an EPID, the portal images are acquired irradiating two different tissue equivalent phantoms at different electron energies. Measurements were performed on an Elekta SL 25 linear accelerator with an amorphous-Si electronic portal imaging device (EPID: iViewGT, Elekta Oncology Systems, Crawley, UK). As a measure of EPID image quality contrast (CR) and signal-to-noise ratio (SNR) are determined. For characterisation of the imaging of the EPID RW3 slabs and a Gammex 467 phantom with different material inserts are used. With increasing electron energy the intensity of photon contamination increases, yielding an increasing signal-to-noise ratio, but images are showing a decreasing contrast. As the signal-to-noise ratio saturates with increasing dose a minimum of 50 MUs is recommended. Even image quality depends on electron energy and diameter of the patient, the acquired results are mostly sufficient to assess the accuracy of beam positioning. In general, the online EPID acquisition has been demonstrated to be an effective electron beam verification and documentation method. The results are showing that this procedure can be recommended to be routinely and reliably done in patient treatment with electron beams.

Medical Terminations of Pregnancy: A Viable Source of Tissue for Cell Replacement Therapy for Neurodegenerative Disorders

“Proof-of-principle” that cell replacement therapy works for neurodegeneration has been reported, but only using donor cells collected from fetal brain tissue obtained from surgical terminations of pregnancy. Surgical terminations of pregnancy represent an increasingly limited supply of donor cells due to the tendency towards performing medical termination in much of Europe. This imposes a severe constraint on further experimental and clinical cell transplantation research. Therefore, we explore here the feasibility of using medical termination tissue as a donor source. Products of conception were retrieved from surgical terminations over the last 7 years and from medical terminations over the last 2.5 years. The number of collections that yielded fetal tissue, viable brain tissue, and identifiable brain regions (ganglionic eminence, ventral mesencephalon, and neocortex) were recorded. We studied cell viability, cell physiological properties, and differentiation potential both in vitro and following transplantation into the central nervous system of rodent models of neurodegenerative disease. Within equivalent periods, we were able to collect substantially greater numbers of fetal remains from medical than from surgical terminations of pregnancy, and the medical terminations yielded a much higher proportion of identifiable and dissectible brain tissue. Furthermore, we demonstrate that harvested cells retain the capacity to differentiate into neurons with characteristics appropriate to the region from which they are dissected. We show that, contrary to widespread assumption, medical termination of pregnancy-derived fetal brain cells represent a feasible and more readily available source of human fetal tissue for experimental cell transplantation with the potential for use in future clinical trials in human neurodegenerative disease.

Neonatal desensitization allows long-term survival of neural xenotransplants without immunosuppression

Preclinical development of human cells for potential therapeutic application in neurodegenerative diseases requires that their long-term survival, stability and functional efficacy be studied in animal models of human disease. Here we describe a strategy for long-term immune protection of human fetal and stem cell-derived neural cells transplanted into the adult rat brain, by desensitizing the host rat to similar cells in the neonatal period, without the need for additional immunosuppression.

Menstrual disorders in rural Gambia

As part of a community-based reproductive morbidity survey in rural Gambia, the prevalence and association of menstrual disorders with sociodemographic characteristics and other reproductive morbidities, and with knowledge, attitudes, and beliefs concerning menstrual problems were assessed. A questionnaire was administered by a field-worker and by a gynecologist, who also examined the women. Semistructured interviews were conducted to assess knowledge, attitudes, and beliefs in a subsample. Of 607 menstruating women not using hormonal contraceptives, 16 percent complained to the gynecologist of irregular cycles, 14 percent of dysmenorrhea, 8 percent of spotting, and 4 percent of heavy or prolonged bleeding. Each complaint was associated with other reproductive morbidities. A minority of women with menstrual problems had sought health care, and menstruation was revealed to be a highly personal and secretive topic in this population. Menstrual disorders constitute an important unaddressed area of reproductive health service needs in developing countries for which relatively simple and inexpensive therapies are often available. Information, education, and support combined with clinical management of menstrual problems should be core elements of reproductive health programs.

Epidemiology of pelvic organ prolapse in rural Gambia, West Africa

OBJECTIVES

To investigate the prevalence of pelvic organ prolapse in rural Gambia.

DESIGN

Community-based reproductive health survey.

POPULATION

1348 women residing in 20 villages in rural Gambia.

METHODS

Health questionnaire and standard gynaecological examination to detect symptoms and signs of pelvic organ prolapse and other reproductive diseases. Association between prolapse, socio-demographic data and other morbidities was examined.

MAIN OUTCOME MEASURES

Presence and degree of pelvic organ prolapse.

RESULTS

Out of 1067 women consenting to speculum examination 488 (46%) were found to have some degree of prolapse. In 152 women (14%) the prolapse was severe enough to warrant surgical intervention. After adjustment for confounders the likelihood of pelvic organ prolapse increased with parity and age and was higher in women of the Wolof tribe, pregnant women, those with insufficient perineum, and moderately and severely anaemic women. Only 13% of women with moderate or severe prolapse reported symptoms on direct questioning.

CONCLUSIONS

Pelvic organ prolapse has a high prevalence in this first community-based study of prolapse in West Africa. Many of those affected did not complain about their problem, thus increasing the large, silent burden of reproductive morbidity in this population. Parity was confirmed to be the strongest risk factor followed by age and anaemia. Ethnic origin was a previously unknown risk factor suggesting possible genetic factors in the pathogenesis of prolapse.

The long-term reproductive health consequences of female genital cutting in rural Gambia: a community-based survey

This paper examines the association between traditional practices of female genital cutting (FGC) and adult women's reproductive morbidity in rural Gambia. In 1999, we conducted a cross-sectional community survey of 1348 women aged 15-54 years, to estimate the prevalence of reproductive morbidity on the basis of women's reports, a gynaecological examination and laboratory analysis of specimens. Descriptive statistics and logistic regression were used to compare the prevalence of each morbidity between cut and uncut women adjusting for possible confounders. A total of 1157 women consented to gynaecological examination and 58% had signs of genital cutting. There was a high level of agreement between reported circumcision status and that found on examination (97% agreement). The majority of operations consisted of clitoridectomy and excision of the labia minora (WHO classification type II) and were performed between the ages of 4 and 7 years. The practice of genital cutting was highly associated with ethnic group for two of the three main ethnic groups, making the effects of ethnic group and cutting difficult to distinguish. Women who had undergone FGC had a significantly higher prevalence of bacterial vaginosis (BV) [adjusted odds ratio (OR)=1.66; 95% confidence interval (CI) 1.25-2.18] and a substantially higher prevalence of herpes simplex virus 2 (HSV2) [adjusted OR=4.71; 95% CI 3.46-6.42]. The higher prevalence of HSV2 suggests that cut women may be at increased risk of HIV infection. Commonly cited negative consequences of FGC such as damage to the perineum or anus, vulval tumours (such as Bartholin's cysts and excessive keloid formation), painful sex, infertility, prolapse and other reproductive tract infections (RTIs) were not significantly more common in cut women. The relationship between FGC and long-term reproductive morbidity remains unclear, especially in settings where type II cutting predominates. Efforts to eradicate the practice should incorporate a human rights approach rather than rely solely on the damaging health consequences.

High-resolution neutron structure of nicotinamide adenine dinucleotide

The structure of the free-acid form of the coenzyme NAD(+) was determined at 100 K from a single-crystal neutron experiment. NAD(+) is the oxidized form of the coenzyme redox pair NAD(+)/NADH and plays an important role in the catalysis of biological processes. The molecule crystallizes in space group P1 with one NAD(+) and four water molecules per unit cell. The structure is compared with the previous X-ray models of NAD(+) [Reddy et al. (1981), J. Am. Chem. Soc. 103, 907-914; Parthasarathy & Fridey (1984b), Science, 226, 969-971; Guillot et al. (2000), Acta Cryst. C56, 726-728]. The crystal packing and the hydrogen-bond pattern are discussed as well as four short C-H.O contacts involving the pyridine and adenine rings. The structure displays stereochemical distortions owing to the hydrogen bonding and crystal-packing constraints, reflecting the adaptability of the NAD(+) molecule in various chemical environments.

The burden of reproductive-organ disease in rural women in The Gambia, West Africa

BACKGROUND

Data on the epidemiology of reproductive-organ morbidity are needed to guide effective interventions, to set health-care priorities, and to target future research. This study aimed to find out the prevalence of reproductive-organ disease in a sample of rural Gambian women.

METHODS

A questionnaire on reproductive health was administered by fieldworkers to women aged 15-54 years living in a rural area under demographic surveillance. A female gynaecologist questioned and examined the women (including speculum and bimanual pelvic examinations). Vaginal swabs were taken to test for Trichomonas vaginalis, Candida albicans, and bacterial vaginosis, cervical smears for cytology, cervical swabs for Chlamydia trachomatis PCR and Neisseria gonorrhoeae culture, and venous blood for haemoglobin, HIV, herpes simplex virus 2, and syphilis serology.

FINDINGS

1348 (72.0%) of 1871 eligible women took part. Reproductive-organ symptoms were more likely to be reported to the gynaecologist (52.7% of women) than to the fieldworker (26.5%). Menstrual problems, abnormal vaginal discharge, and vaginal itching were the most commonly reported symptoms. A minority of women said they had sought health care for their symptoms. The frequencies of reproductive-organ morbidity were high: menstrual dysfunction 34.1% (95% CI 29.6-39.1), infertility 9.8% (8.2-11.6), reproductive-tract infections 47.3% (43.7-51.0), pelvic tenderness 9.8% ((7.0-13.5), cervical dysplasia 6.7% (5.2-8.4), masses 15.9% (12.5-20.1), and childbirth-related damage to pelvic structures 46.1% (40.1-52.3). 948 (70.3%) women had at least one reproductive-organ disorder.

INTERPRETATION

For these rural women, whose lives depend heavily on their reproductive function, reproductive-organ disease is a large burden. In inadequately resourced rural areas, with poor education, heavy agricultural and domestic labour, and limited access to quality health care, many women are not able to attain and maintain reproductive health and wellbeing.

Dose reduction in spiral CT angiography of thoracic outlet syndrome by anatomically adapted tube current modulation

The aim of this study was to evaluate dose reduction in spiral CT angiography of the thoracic outlet by on-line tube-current control. Prospectively, 114 patients undergoing spiral CT angiography of the subclavian artery for thoracic outlet arterial syndromes were evaluated with and without tube-current modulation at the same session (scanning parameters for the two successive angiograms, one in the neutral position and one after the postural maneuver): 140 kV; 206 mA; scan time 0.75 s; collimation 3 mm; pitch = 1). The dose reduction system was applied in the neutral position in the first 92 consecutive patients and after postural maneuver in the remaining 22 consecutive patients. Dose reduction and image quality were analyzed in the overall study group (group 1; n = 114). The influence of the arm position was assessed in 44 of the 114 patients (group 2), matched by the transverse diameter of the upper thorax. The mean dose reduction was 33% in group 1 (range 22-40%) and 34% in group 2 (range 26-40%). In group 2 the only difference in image quality was a significantly higher frequency of graininess on low-dose scans compared with reference scans whatever the patient's arm position, graded as minimal in 38 of the 44 patients (86%). When the low-dose technique was applied after postural maneuver in group 2: (a) the mean dose reduction was significantly higher (35 vs 32% in the neutral position; p = 0.006); (b) graininess was less frequent (82 vs 91% in the neutral position); and (c) the percentage of graininess graded as minimal was significantly higher (83 vs 70% in the neutral position; p = 0.2027). On-line tube-current modulation enables dose reduction on high-quality, diagnostic spiral CT angiograms of the thoracic outlet and should be applied during data acquisition in the neutral position and after postural maneuver for optimal use.

[Age-related contractility of retinal arterioles during pure oxygen breathing]

BACKGROUND

Pure oxygen breathing is a non-invasive method to test the contractility of retinal arterioles. The normal response curve of this provocation method was tested using the Retinal Vessel Analyzer (RVA). Statistical analysis between groups was performed with th Man-Whitney test, correlations were tested with Pearsons' linear function.

METHODS

After a 3-min baseline measurement 32 healthy volunteers breathed 100% oxygen for 5 min. The diameter of an retinal arteriole was measured continuously during this provocation by the RVA. Volunteers were separated into four groups according age.

RESULTS

All four groups reacted to pure oxygen breathing with significant vasoconstriction of the retinal arteriole: in the youngest group (20-29 years) the reduction was 14.6 +/- 5.2% and the three older age groups 9.4 +/- 5.2%, 4.6 +/- 2.7%, and 2.8 +/- 3.3%. The correlation between vasoconstriction and age was r = 0.73.

CONCLUSIONS

Pure oxygen breathing is an easily performed method with minimal invasiveness to the patient. However, the age-correlated response curve must be kept in mind for the clinical use of this method.

Feasibility of C-arm-supported CT fluoroscopy in percutaneous abscess drainage procedures

PURPOSE

Evaluation of C-arm-supported CT fluoroscopy to facilitate percutaneous abscess drainage procedures.

METHODS

Prospectively, 40 percutaneous drainage procedures were performed either with C-arm-supported CT fluoroscopy or with CT fluoroscopy alone. Hybrid imaging was performed on the CT couch after complementing a CT fluoroscopy scanner with a C-arm fluoroscopy unit. Procedure times, drainage revisions during follow-up, and postinterventional drainage periods were analyzed.

RESULTS

When compared with exclusive CT fluoroscopic guidance, a median procedure time of 9 +/- 3.7 min versus 14.8 +/- 7.3 min was required for C-arm-supported CT fluoroscopy (p < 0.005, t-test). During follow-up, eight drainage catheters had to be revised within the exclusive CT fluoroscopy group, while only two revisions were necessary within the C-arm-supported CT fluoroscopy group. With C-arm-supported CT fluoroscopy, postinterventional drainage periods were reduced (median 13 vs 19 days; p < 0.001, t-test).

CONCLUSION

Compared with exclusive cross-sectional image guidance, C-arm-supported CT fluoroscopy seems to improve placement of abscess drainage catheters to possibly reduce procedure times, drainage catheter revisions, and postinterventional drainage periods.

Comparison of C-arm CT fluoroscopy and conventional fluoroscopy for percutaneous biliary drainage procedures

PURPOSE

To conduct a prospective randomized evaluation of C-arm computed tomography (CT) fluoroscopy for external biliary drainage procedures in comparison with conventional fluoroscopic guidance to reduce the number of transhepatic punctures as a primary endpoint.

MATERIALS AND METHODS

In 18 patients with biliary obstructions, 20 external percutaneous biliary drainage procedures were prospectively performed with use of either C-arm CT fluoroscopy or conventional fluoroscopy alone. The number of hepatic punctures, procedure time, and fluoroscopy time, were analyzed separately for both methods.

RESULTS

C-arm CT fluoroscopy resulted in a reduced number of transhepatic punctures, with decreased procedure and fluoroscopy times (P < .05; t test). When compared with conventional external biliary drainage procedures, a mean of 1.8+/-1 versus 4.8+/-2.8 hepatic punctures at a fluoroscopy time of 3.4+/-1.5 versus 11.4+/-7.4 minutes was required for C-arm CT fluoroscopy, while procedure times were 11+/-3.6 versus 16.2+/-9.3 minutes.

CONCLUSIONS

C-arm CT fluoroscopy is associated with decreased procedure and fluoroscopy times, while fewer transhepatic punctures are required to establish external biliary drainage.

First experiences in percutaneous arterial chemoembolization of malignant liver lesions by means of real-time CT fluoroscopy

Computed tomography fluoroscopy (CTF) allows real-time display (continuous imaging) and has been increasingly used in interventional procedures. We wished to demonstrate the usefulness of CTF in chemoembolization of the liver. Twenty-one patients with primary or secondary malignant lesions of the liver underwent CTF-guided chemoembolization after angiographic positioning of a catheter in the hepatic artery. Embolization materials such as Lipiodol and mitomycin C were administered under continuous CT scanning. CTF led to a change of the method (correction of catheter position, application of norepinephrine) in nine of 21 cases. There were no fatal complications.

Immunohistochemical localization of laminin, nidogen, and type IV collagen during the early development of human liver

There is evidence that basement membrane components control differentiation of liver sinusoids and bile ducts. These processes occur in humans in the 9th gestational week (GW). Distribution of laminin, nidogen, and type IV collagen was studied during human liver development between the 6th and the 10th GW. Laminin and nidogen lined intrahepatic microvessels in the 6th and 7th GW decreasing in quantity at the beginning of the fetal period (9th-10th GW). Type IV collagen was detected in microvessels only from the 9th GW onward. In the early periportal matrix (9th-10th GW) laminin, nidogen, and type IV collagen were diffusely distributed. At these stages, basement membrane zones of larger portal vessels and of early bile ducts were also stained for all three glycoproteins. These results show that laminin and nidogen are localized in microvessels during early human liver development and decrease in concentration at the developmental stage during which microvessels become discontinuous. In contrast, type IV collagen is not present in early microvessels but occurs when laminin and nidogen disappear. The three glycoproteins occur together only in those areas of the developing liver in which, from the 9th GW onward, the differentiation of immature liver cells into biliary epithelium takes place.

Effects of left heart bypass on cardiac performance following myocardial ischemia

A series of nine dogs underwent 20 minutes of myocardial ischemia by cross clamping the aorta while total cardiopulmonary bypass. The four dogs that did not have subsequent left bypass all showed a deterioration of ventricular function curve 30 minutes after restarting the heart beat when compared to their own preischemic values. The five animals which were supported for 30 minutes in left heart after bypass all showed essentially unchanged cardiac function after bypass. This study suggests that an improvement of myocardial performance after ischemic damage can be achieved with left heart bypass.