Evaluation of a new image reconstruction method for digital breast tomosynthesis: effects on the visibility of breast lesions and breast density

OBJECTIVE

To compare image quality and breast density of two reconstruction methods, the widely-used filtered-back projection (FBP) reconstruction and the iterative heuristic Bayesian inference reconstruction (Bayesian inference reconstruction plus the method of total variation applied, HBI).

METHODS

Thirty-two clinical DBT data sets with malignant and benign findings, n = 27 and 17, respectively, were reconstructed using FBP and HBI. Three experienced radiologists evaluated the images independently using a 5-point visual grading scale and classified breast density according to the American College of Radiology Breast Imaging-Reporting And Data System Atlas, fifth edition. Image quality metrics included lesion conspicuity, clarity of lesion borders and spicules, noise level, artifacts surrounding the lesion, visibility of parenchyma and breast density.

RESULTS

For masses, the image quality of HBI reconstructions was superior to that of FBP in terms of conspicuity,clarity of lesion borders and spicules (p < 0.01). HBI and FBP were not significantly different in calcification conspicuity. Overall, HBI reduced noise and supressed artifacts surrounding the lesions better (p < 0.01). The visibility of fibroglandular parenchyma increased using the HBI method (p < 0.01). On average, five cases per radiologist were downgraded from BI-RADS breast density category C/D to A/B.

CONCLUSION

HBI significantly improves lesion visibility compared to FBP. HBI-visibility of breast parenchyma increased, leading to a lower breast density rating. Applying the HBIR algorithm should improve the diagnostic performance of DBT and decrease the need for additional imaging in patients with dense breasts.

ADVANCES IN KNOWLEDGE

Iterative heuristic Bayesian inference (HBI) image reconstruction substantially improves the image quality of breast tomosynthesis leading to a better visibility of breast carcinomas and reduction of the perceived breast density compared to the widely-used filtered-back projection (FPB) reconstruction. Applying HBI should improve the accuracy of breast tomosynthesis and reduce the number of unnecessary breast biopsies. It may also reduce the radiation dose for the patients, which is especially important in the screening context.

[Importance of diffusion imaging in liver metastases]

CLINICAL/METHODICAL ISSUE

Detection and characterization of focal liver lesions.

STANDARD RADIOLOGICAL METHODS

Due to its excellent soft tissue contrast, the availability of liver-specific contrast agents and the possibility of functional imaging, magnetic resonance imaging (MRI) is the method of choice for the evaluation of focal liver lesions.

METHODICAL INNOVATIONS

Diffusion-weighted imaging (DWI) enables generation of functional information about the microstructure of a tissue besides morphological information.

PERFORMANCE

In the detection of focal liver lesions DWI shows a better detection rate compared to T2w sequences and a slightly poorer detection rate compared to dynamic T1w sequences. In principle, using DWI it is possible to distinguish malignant from benign liver lesions and also to detect a therapy response at an early stage.

ACHIEVEMENTS

For both detection and characterization of focal liver lesions, DWI represents a promising alternative to the morphological sequences; however, a more detailed characterization with the use of further sequences should be carried out particularly for the characterization of solid benign lesions. For the assessment and prognosis of therapy response, DWI offers advantages compared to morphological sequences.

PRACTICAL RECOMMENDATIONS

For the detection of focal liver lesions DWI is in principle sufficient. After visual detection of a solid liver lesion a more detailed characterization should be carried out using further sequences (in particular dynamic T1w sequences). The DWI procedure should be used for the assessment and prognosis of a therapy response.

The Assessment of Background Parenchymal Enhancement (BPE) in a High-Risk Population: What Causes BPE?

OBJECTIVE

To investigate promoting factors for background parenchymal enhancement (BPE) in MR mammography (MRM).

METHODS

146 patients were retrospectively evaluated, including 91 high-risk patients (50 BRCA patients, 41 patients with elevated lifetime risk). 56 screening patients were matched to the high-risk cases on the basis of age. The correlation of BPE with factors such as fibroglandular tissue (FGT), age, menopausal status, breast cancer, high-risk precondition as well as motion were investigated using linear regression.

RESULTS

BPE positively correlated with FGT (P<.001) and negatively correlated with menopausal status (P<.001). Cancer did not show an effect on BPE (P>.05). A high-risk precondition showed a significant impact on the formation of BPE (P<.05). However, when corrected for motion, the correlation between BPE and a high-risk precondition became weak and insignificant, and a highly significant association between BPE and motion was revealed (P<.01).

CONCLUSION

BPE positively correlated with FGT and negatively correlated with age. Cancer did not have an effect on BPE. A high-risk precondition appears to have a negative effect on BPE. However, when corrected for motion, high-risk preconditions became insignificant. Technical as well as physiological influences seem to play an important role in the formation of BPE.

Breast MR imaging for the assessment of residual disease following initial surgery for breast cancer with positive margins

OBJECTIVES

To determine the accuracy of post-operative MR in predicting residual disease in women with positive margins, emphasizing the size thresholds at which residual disease can be confidently identified.

METHODS

This IRB-approved HIPAA-compliant retrospective study included 175 patients with MR after positive margins following initial surgery for breast cancer. Two expert readers independently re-evaluated MR images for evidence of residual disease at the surgical cavity and multifocal/multicentric disease. All patients underwent definitive surgery and MR findings were correlated to histopathology.

RESULTS

139/175 (79.4%) patients had residual disease at surgery. Average overall sensitivity, specificity, PPV and NPV for residual disease at the surgical cavity were 73%, 72%, 91% and 45%, respectively. The readers identified 42/45 (93%, reader 1) and 43/45 (95%, reader 2) patients with residual invasive disease at the cavity of ≥5 mm and 22/22 (100%, both readers) patients with disease ≥10 mm. Average sensitivity, specificity, PPV and NPV for unknown multifocal/multicentric disease were 90%, 96%, 93% and 86%, respectively.

CONCLUSIONS

Post-operative breast MR can accurately depict ≥5-mm residual disease at the surgical cavity and unsuspected multifocal/multicentric disease. These findings have the potential to lead to more appropriate selection of second surgical procedures in women with positive margins.

KEY POINTS

• Post-operative breast MRI accurately defines residual disease of ≥5 mm. • Surgical cavity sensitivities were high for both invasive carcinoma and DCIS. • Post-surgical changes and very small residual disease (<5 mm) may overlap. • Post-operative breast MRI may help planning an accurate re-resection.

Breast cancer detection and tumor characteristics in BRCA1 and BRCA2 mutation carriers

PURPOSE

To describe imaging findings, detection rates, and tumor characteristics of breast cancers in a large series of patients with BRCA1 and BRCA2 mutations to potentially streamline screening strategies.

METHODS

An IRB-approved, HIPAA-compliant retrospective analysis of 496 BRCA mutation carriers diagnosed with breast carcinoma from 1999 to 2013 was performed. Institutional database and electronic medical records were reviewed for mammography and MRI imaging. Patient and tumor characteristics including age at diagnosis, tumor histology, grade, receptor, and nodal status were recorded.

RESULTS

Tumors in BRCA1 mutation carriers were associated exhibited significantly higher nuclear and histological grade compared to BRCA2 (p < 0.001). Triple-negative tumors were more frequent in BRCA1 mutation carriers, whereas hormone receptor-positive tumors were more frequent in BRCA2 mutation carriers (p < 0.001). BRCA2 mutation carriers more frequently presented with ductal carcinoma in situ (DCIS) alone 14% (35/246) and cancers more frequently exhibiting calcifications (p < 0.001). Mammography detected fewer cancers in BRCA1 mutation carriers compared to BRCA2 (p = 0.04): 81% (186/231) BRCA1 versus 89% (212/237) BRCA2. MRI detected 99% cancers in each group. Mammography detected cancer in two patients with false-negative MRI (1 invasive cancer, 1 DCIS). Detection rates on both mammography and MRI did not significantly differ for women over 40 years and women below 40 years.

CONCLUSIONS

Breast cancers in BRCA1 mutation carriers are associated with more aggressive tumor characteristics compared to BRCA2 and are less well seen on mammography. Mammography rarely identified cancers not visible on MRI. Thus, the omission of mammography in BRCA1 mutation carriers screened with MRI can be considered.

The value of "constant sharpness" as a diagnostic sign in MR-Mammography

Purpose

To examine “constant lesion sharpness” as a morphological diagnostic sign in the differential diagnosis between benign and malignant lesions.

Material and methods

This prospective study had institutional review board approval and was HIPAA compliant. In total 1014 consecutive patients were examined (mean age 55 years ± 13 years) and evaluated in our University hospital towards the morphological shape of the lesion borders. The “Constant sharpness Sign” was defined as a lesion remaining continuously sharp for the duration of the dynamic scan. Inclusion criteria were unclear findings (e.g. BIRADS III/IV), Preoperative staging (BRIDAS IV/V), and referred patients from local clinic of gynecology. Exclusion criteria were MRM-examination ≤1 year before, status after surgery and/or biopsy, chemotherapy and/or radiation therapy. Reference Standard was histological verification. Images were diagnosed by two experienced radiologists in consensus, blinded to the standard of reference.

Results

1014 patients with 1084 lesions (436 benign, 648 malignant lesions) were included into the study.

41.5% of benign lesions and 6.8% (181/436) of malignant lesions displayed a constant sharpness as an accompanying morphological sign (P < 0.001). This resulted in a sensitivity of 41.5%, specificity of 93.2%, a positive likelihood ratio of 6.1%, a negative likelihood ratio of 0.63 and an odd’s ratio of 9,7%.

Summary and conclusion

The constant sharpness sign seems to be an accurate predictor of benign breast lesions, which may help to increase the accuracy of MRM as a morphological sign.

Impact of Tumor Localization and Method of Preoperative Biopsy on Sentinel Lymph Node Mapping After Periareolar Nuclide Injection

BACKGROUND

To evaluate whether tumor localization and method of preoperative biopsy affect sentinel lymph node (SLN) detection after periareolar nuclide injection in breast cancer patients.

METHODS AND FINDINGS

767 breast cancer patients were retrospectively included. For lymphscintigraphy periareolar nuclide injection was performed and the SLN was located by gamma camera. Patient and tumor characteristics were correlated to the success rate of SLN mapping. SLN marking failed in 9/61 (14.7%) patients with prior vacuum-assisted biopsy and 80/706 (11.3%) patients with prior core needle biopsy. Individually evaluated, biopsy method (p = 0.4) and tumor localization (p = 0.9) did not significantly affect the SLN detection rate. Patients with a vacuum-assisted biopsy of a tumor in the upper outer quadrant had a higher odds ratio of failing in SLN mapping (OR 3.8, p = 0.09) compared to core needle biopsy in the same localization (OR 0.9, p = 0.5).

CONCLUSIONS

Tumor localization and preoperative biopsy method do not significantly impact SLN mapping with periareolar nuclide injection. However, the failure risk tends to rise if vacuum-assisted biopsy of a tumor in the upper outer quadrant is performed.

[Value of galactography for the diagnostic work-up of pathological nipple discharge in multimodal breast diagnostics. Part 2: a systematic review of the literature]

BACKGROUND

The survey results of a previous study showed that galactography is now rarely used in Germany and newer methods are applied. The evidential value of galactography should be established and opposed to the evidential value of ultrasound (US) and magnetic resonance mammography (MRM).

MATERIALS AND METHODS

A search was carried out in PubMed and Cochrane involving studies written in English or German. The level of evidence was measured according to the Oxford Centre for Evidence-based Medicine.

RESULTS

A total of 19 studies were included, 14 with results on galactography, 10 on US and 5 on MRM. Almost all studies were retrospective with an evidence assigned to level 3b or lower. The results on the diagnostic values showed a very wide range. Because of very variable numbers of cases and consideration of various pathologies, the studies are only comparable to a limited extent.

CONCLUSION

Galactography, US and MRM all show a weak level of evidence and no superiority of a particular method can be derived. Therefore, galactography can no longer be considered as a mandatory standard in modern multimodal imaging of the breast. Recommendations for the diagnostic work-up of pathological nipple discharge have to be included in current guidelines and must consider these facts.

Is "prepectoral edema" a morphologic sign for malignant breast tumors?

RATIONALE AND OBJECTIVES

A variety of morphologic and kinetic signs of benign or malignant breast lesions contribute to a final diagnosis and differential diagnosis in magnetic resonance (MR) mammography (MRM). As a new sign, prepectoral edema (PE) in patients without any history of previous biopsy, operation, radiation, or chemotherapy was detected during routine breast MR examinations. The purpose of this study was to retrospectively evaluate the role of this morphologic sign in the differential diagnosis of breast lesions.

MATERIALS AND METHODS

Between January 2005 and October 2006, a total of 1109 consecutive MRM examinations have been performed in our institution. In this study, only patients who would later be biopsied or operated in our own hospital were included. They had no previous operation, biopsy, intervention, chemotherapy, hormone replacement therapy, or previous mastitis. In total, 162 patients with 180 lesions were included, histologically correlated later-on by open biopsy (124 patients and 136 lesions) or core biopsy (38 patients and 44 lesions). The evaluations were performed by four experienced radiologists in consensus.

RESULTS

One hundred eighty evaluated lesions included 104 malignant lesions (93 invasive and 11 noninvasive cancers) and 76 benign lesions. PE was detected in 2.6% of benign lesions (2 of 76), in none of the Ductal cacinoma in situ (DCIS) cases (0 of 11), and in 25.8% of malignant lesions (24 of 93; P < .000). PE was found significantly more frequently in presence of malignant tumors >2 cm in diameter (48.5%, 17 of 35 vs. 13.8%, 8 of 58; P < .001). PE was not statistically associated to malignant tumor type, presence or absence of additional DCIS, and number of lesions. This resulted in the following diagnostic parameters for PE as an indicator for malignancy: sensitivity of 19.3%, specificity of 97.3%, positive predictive value (PPV) of 92.3%, negative predictive value of 48%, and accuracy of 57.7%.

CONCLUSIONS

In case of occurrence, the "PE sign" seems to be a specific indicator for malignant tumors with a high PPV, independent from its entity.

(18) F-FDG PET/CT for initial staging in breast cancer patients - Is there a relevant impact on treatment planning compared to conventional staging modalities?

OBJECTIVE

To evaluate the impact of whole-body (18) F-FDG PET/CT on initial staging of breast cancer in comparison to conventional staging modalities.

METHODS

This study included 102 breast cancer patients, 101 patients were eligible for evaluation. Preoperative whole-body staging with PET/CT was performed in patients with clinical stage ≥ T2 tumours or positive local lymph nodes (n = 91). Postoperative PET/CT was performed in patients without these criteria but positive sentinel lymph node biopsy (n = 10). All patients underwent PET/CT and a conventional staging algorithm, which included bone scan, chest X-ray and abdominal ultrasound. PET/CT findings were compared to conventional staging and the impact on therapeutic management was evaluated.

RESULTS

PET/CT led to an upgrade of the N or M stage in overall 19 patients (19 %) and newly identified manifestation of breast cancer in two patients (2 %). PET/CT findings caused a change in treatment of 11 patients (11 %). This is within the range of recent studies, all applying conventional inclusion criteria based on the initial T and N status.

CONCLUSIONS

PET/CT has a relevant impact on initial staging and treatment of breast cancer when compared to conventional modalities. Further studies should assess inclusion criteria beyond the conventional T and N status, e.g. tumour grading and receptor status.

KEY POINTS

• PET/CT may be relevant in staging breast cancer patients at higher risk for metastases • PET/CT may modify the N and M stage in multiple patients • PET/CT may impact treatment planning in breast cancer patients.

DCE-MRI of the breast in a stand-alone setting outside a complementary strategy - results of the TK-study

OBJECTIVES

To evaluate the accuracy of MRI of the breast (DCE-MRI) in a stand-alone setting with extended indications.

MATERIALS AND METHODS

According to the inclusion criteria, breast specialists were invited to refer patients to our institution for DCE-MRI. Depending on the MR findings, patients received either a follow-up or biopsy. Between 04/2006 and 12/2011 a consecutive total of 1,488 women were prospectively examined.

RESULTS

Of 1,488 included patients, 393 patients were lost to follow-up, 1,095 patients were evaluated. 124 patients were diagnosed with malignancy by DCE-MRI (76 TP, 48 FP, 971 TN, 0 FN cases). Positive cases were confirmed by histology, negative cases by MR follow-ups or patient questionnaires over the next 5 years in 1,737 cases (sensitivity 100 %; specificity 95.2 %; PPV 61.3 %; NPV 100 %; accuracy 95.5 %). For invasive cancers only (DCIS excluded), the results were 63 TP; 27 FP; 971 TP and 0 FN (sensitivity 100 %; specificity 97.2 %; PPV 70 %; NPV 100 %; accuracy 97.5 %).

CONCLUSION

The DCE-MRI indications tested imply that negative results in DCE-MRI reliably exclude cancer. The results were achieved in a stand-alone setting (single modality diagnosis). However, these results are strongly dependent on reader experience and adequate technical standards as prerequisites for optimal diagnoses.

KEY POINTS

• DCE-MRI of the breast has a high accuracy in finding breast cancer. • The set of indications for DCE-MRI of the breast is still very limited. • DCE-MRI can achieve a high accuracy in a 'screening-like' setting. • Accuracy of breast DCE-MRI is strongly dependent on technique and reader experience. • A negative DCE-MRI effectively excludes cancer.

[Value of galactography for the diagnostic work-up of pathological nipple discharge in multimodal breast diagnostics : Part 1: An online survey among German breast care centers.]

PURPOSE

Galactography has been used in cases of pathological discharge for decades. Meanwhile other methods, such as high-resolution ultrasound (US) and magnetic resonance mammography (MRM) have been established for modern multimodal breast imaging. A survey among certified German breast care centers aimed to investigate to what extent galactography is currently used and whether newer techniques in multimodal imaging are preferred.

MATERIALS AND METHODS

An anonymous online survey was carried out nationwide and open to 342 radiology units in certified German breast care centers.

RESULTS

A total of 177 units (52 %) participated in the survey of which 13 % generally do not provide galactography, 33 % conduct a maximum of 5 galactographies per year, 24 % conduct 6-10, 18 % 11-20, 8 % 21-50 and 5 % 51-100. Of the participants 53 % give first priority to US and prefer galactography to MRM in stepwise diagnosis and 32 % prefer MRM to galactography. Only 4 % use galactography initially.

CONCLUSION

Currently galactography is no longer a mandatory standard and newer methods are preferred. The evidential value of galactography in comparison to other techniques should be established on the basis of the literature. The second part of this paper will deal with this question.

Is the assessment of the central skeleton sufficient for osseous staging in breast cancer patients? A retrospective approach using bone scans

OBJECTIVE

By analyzing bone scans we aimed to determine whether the assessment of the central skeleton is sufficient for osseous staging in breast cancer patients. This might be of interest for future staging modalities, especially positron emission tomography/computed tomography, usually sparing the peripheral extremities, as well as the skull.

MATERIALS AND METHODS

In this retrospective study, a total of 837 bone scans for initial staging or restaging of breast cancer were included. A total of 291 bone scans in 172 patients were positive for bone metastases. The localization and distribution of the metastases were re-evaluated by two readers in consensus. The extent of the central skeleton involvement was correlated to the incidence of peripheral metastases.

RESULTS

In all 172 patients bone metastases were seen in the central skeleton (including the proximal third of humerus and femur). In 34 patients (19.8 %) peripheral metastases of the extremities (distally of the proximal third of humerus and femur) could be detected. Sixty-four patients (37.2 %) showed metastases of the skull. Summarizing the metastases of the distal extremities and skull, 79 patients (45.9 %) had peripheral metastases. None of the patients showed peripheral metastases without any affliction of the central skeleton. The incidence of peripheral metastases significantly correlated with the extent of central skeleton involvement (p<0.001).

CONCLUSIONS

Regarding bone scans, an isolated metastatic spread to the peripheral skeleton without any manifestation in the central skeleton seems to be the exception. Thus, the assessment of the central skeleton should be sufficient in osseous breast cancer staging and restaging. However, in case of central metastases, additional imaging of the periphery should be considered for staging and restaging.

First description of MR mammographic findings in the tumor bed after intraoperative radiotherapy (IORT) of breast cancer

The aim was to investigate changes in the tumor bed on magnetic resonance mammography (MRM) after intraoperative radiotherapy (IORT) and whether they would limit the diagnostic value of posttherapeutic MRM. We retrospectively investigated 36 patients undergoing MRM after IORT (median interval 2.8 years, range 0.4-7.1). Wound cavities with fat necrosis were common after IORT (81%). They were associated with persisting contrast enhancement, i.e., enhancement was mostly seen irrespective of the posttherapeutic interval. It normally presented as rim enhancement and did not cause any diagnostic uncertainty if viewed together with other tissue characteristics. We do not expect a limited diagnostic value of MRM after IORT.

Overexpression of CD36 and acyl-CoA synthetases FATP2, FATP4 and ACSL1 increases fatty acid uptake in human hepatoma cells

BACKGROUND

Understanding the mechanisms of long chain fatty acid (LCFA) uptake in hepatic cells is of high medical importance to treat and to prevent fatty liver disease (FLD). ACSs (Acyl-CoA synthetases) are a family of enzymes that catalyze the esterification of fatty acids (FA) with CoA. Recent studies suggest that ACS enzymes drive the uptake of LCFA indirectly by their enzymatic activity and could promote special metabolic pathways dependent on their localization.The only protein located at the plasma membrane which has consistently been shown to enhance FA uptake is CD36.

AIMS

The current study investigated whether ACSs and CD36 could regulate hepatic LCFA uptake.

METHODS AND RESULTS

FATP2 and FATP4 were both localized to the ER of HuH7 and HepG2 cells as shown by double immunofluorescence in comparison to marker proteins. ACSL1 was located at mitochondria in both cell lines. Overexpression of FATP2, FATP4 and ACSL1 highly increased ACS activity as well as the uptake of [3H]-oleic acid and fluorescent Bodipy-C12 (B12) fatty acid. Quantitative FACS analysis showed a correlation between ACS expression levels and B12 uptake. FATP2 had the highest effect on B12 uptake of all proteins tested. CD36 was mainly localized at the plasma membrane. Whereas [3H]-oleic acid uptake was increased after overexpression, CD36 had no effect on B12 uptake.

CONCLUSION

Uptake of LCFA into hepatoma cells can be regulated by the expression levels of intracellular enzymes. We propose that ACS enzymes drive FA uptake indirectly by esterification. Therefore these molecules are potential targets for treatment of nonalcoholic fatty liver disease (NAFLD) or steatohepatitis (NASH).

Postoperative feeding: a clinical review

The tradition of withholding postoperative enteral feeds until the spontaneous resolution of ileus, demonstrated by the return of flatus or bowel movement is not supported by the literature. There is an abundance of evidence from the basic science and general surgery literature that supports early feeding after surgery. This is a review of the available literature on postoperative feeding, including data from gastrointestinal physiology. We conclude that early feeding is safe and well tolerated after most obstetric and gynecologic procedures and will lead to decreased cost, shorter hospitalization, and improved patient satisfaction.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians

LEARNING OBJECTIVES

After completion of this article, the reader will be able to summarize the current literature regarding early postoperative feeding; to identify which patients can be offered early postoperative feeding, as well as list the risks and benefits of early postoperative feeding; and to explain the normal gastrointestinal physiology after abdominal surgery.

The value of the cervical score in predicting successful outcome of labor induction

OBJECTIVE

To compare cervical dilation and the Bishop score as correlates of successful labor induction and vaginal delivery and to determine whether the prognosis of post-ripening cervical characteristics varies with the method of ripening used.

METHODS

Four hundred forty-three women with Bishop scores less than 9 who required induction of labor were assigned randomly to cervical ripening with prostaglandin E2 gel or hygroscopic dilation. The Bishop score and its component characteristics were evaluated as univariate correlates of successful induction of labor and vaginal delivery and then were assessed using logistic regression to adjust for other maternal and fetal factors. The differences in the association between method of ripening and successful labor induction were evaluated relative to pre-ripening and post-ripening cervical examination characteristics.

RESULTS

Cervical dilation was a better correlate of successful labor induction and vaginal delivery than was the Bishop score, even after exclusion of patients with initial Bishop scores greater than 6 and dilation greater than 3.0. Both ripening methods yielded similar success in labor induction and vaginal delivery, but when categorized by post-ripening cervical examinations, patients undergoing hygroscopic ripening had lower rates of successful labor induction and vaginal delivery.

CONCLUSION

Cervical dilation is a better predictor of successful labor induction and vaginal delivery than either the Bishop score or any other Bishop score component characteristic. The likelihood of successful labor induction and vaginal delivery based on post-ripening cervical characteristics varies by the ripening method used.

Pre-induction cervical ripening: a randomized comparison of two methods

OBJECTIVES

To compare two methods of pre-induction cervical ripening in a randomized clinical trial.

METHODS

A single intracervical prostaglandin E2 (PGE2) gel application was compared with a single insertion of hygroscopic dilators in 441 women at term with unfavorable cervical scores. Induction success was defined as entry into active labor within 6 hours of oxytocin infusion.

RESULTS

There was no statistical difference in pre- or post-ripening cervical scores. In the group receiving hygroscopic dilators, only 28% entered the active phase of labor within 6 hours of oxytocin infusion compared with 45% (P < .001) in the PGE2 group. Thus, in this study, a change in cervical score did not directly predict induction success. There was a higher rate of postpartum endometritis (24 versus 14%; P = .007) and suspected neonatal infection (10 versus 5%; P = .03) in the dilator group.

CONCLUSIONS

Pre-induction ripening by hygroscopic dilators and intracervical PGE2 was equivalent as measured by changes in the cervical score. The change in cervical score, however, was not predictive of successful induction, and PGE2 was more frequently associated with induction success. Hygroscopic dilators were associated with a higher incidence of postpartum maternal and neonatal infection because of a longer duration of labor. Hospital charges for intracervical PGE2 gel totaled $522 compared with $91 for the insertion of three dilators.

Patient-administered outpatient intravaginal prostaglandin E2 suppositories in post-date pregnancies: a double-blind, randomized, placebo-controlled study

OBJECTIVE

To shorten post-date pregnancies in a safe, effective manner by outpatient acceleration of cervical ripening.

METHODS

Eighty patients with uncomplicated pregnancies at or beyond 41 weeks' gestation and a cervical Bishop score less than 9 were randomized to daily self-administered, 2-mg intravaginal prostaglandin E2 (PGE2) or placebo suppositories. Each followed a standard post-date antepartum surveillance protocol. Patients were admitted for spontaneous labor or for induction if the Bishop score reached 9, antepartum testing was nonreassuring, exclusion criteria were fulfilled, or if the gestational age reached 44 weeks.

RESULTS

Fewer suppositories were used in the PGE2 group (four versus seven; P = .006), resulting in earlier gestational age on admission (295 versus 297 days; P = .021) and lower antepartum testing charges ($476.97 versus $647.29; P = .001). Labor and delivery time was significantly decreased in nulliparas (10.7 +/- 5.1 versus 15.3 +/- 7.6 hours; P = .035).

CONCLUSIONS

Daily low-dose, patient-administered PGE2 vaginal suppositories can decrease the gestational length and cost of uncomplicated post-date pregnancies by reducing the time to achieve a favorable cervix, the need for antepartum testing, and, potentially, post-date-related complications.

The effect of acetaminophen on prostacyclin production in pregnant women

OBJECTIVE

The purpose of this study was to determine if acetaminophen decreased prostacyclin production by endothelial cells in culture and by pregnant women.

STUDY DESIGN

The effect of acetaminophen on endothelial cells in culture was determined by the addition of acetaminophen in concentrations of 10 and 100 micrograms/ml with comparison to control and indomethacin at 10 micrograms/ml. Prostacyclin production was estimated in 24 and thromboxane A2 production in six third-trimester pregnant women by measurement of excretion of urinary metabolites before and after ingestion of either 1000 mg of acetaminophen or placebo.

RESULTS

Compared with control (549 +/- 61 pg/well, mean +/- SD), production of prostacyclin in vitro was significantly inhibited by acetaminophen at 10 micrograms/ml (321 +/- 25) and 100 micrograms/ml (257 +/- 14). This inhibition is similar to inhibition by 10 micrograms/ml of indomethacin (228 +/- 11). Excretion of prostacyclin metabolite was significantly lower after ingestion of acetaminophen (2233 +/- 446 vs 1246 +/- 199 pg/mg creatinine, mean +/- SEM) but unchanged after ingestion of placebo (1745 +/- 304 vs 1712 +/- 211). There was no difference in response between normal and hypertensive women, and there was no effect of acetaminophen on thromboxane metabolite excretion.

CONCLUSION

Acetaminophen in typical oral doses results in reduced production of prostacyclin by endothelial cells in culture and in a reduction in prostacyclin, but not thromboxane, production in pregnant women.

Potential role of endothelin-1 in normal and hypertensive pregnancies

Endothelins are the most potent naturally occurring vasoconstrictors yet discovered. Both normal and abnormal pregnancies are associated with significant changes in vascular smooth muscle; therefore the potential role of endothelin in pregnancy was investigated. Plasma immunoreactive endothelin-1 concentration was measured by radioimmunoassay in blood from women with normal pregnancy and preeclampsia and in cord blood from normal pregnancies. Endothelin-1 levels were elevated in pregnant women during labor when compared with levels in nonpregnant women and patients with normal pregnancies before labor. Preeclampsia in nonlaboring women before treatment was associated with higher endothelin values when compared with values in normal nonlaboring patients and women with preeclampsia after magnesium sulfate infusion. The umbilical venous concentration of endothelin was 10 times higher than normal pregnant levels and four times higher than levels in laboring patients.