Effect of radioprotective curtain length on the scattered dose rate distribution and endoscopist eye lens dose with an over-couch fluoroscopy system.

Sufficient dose reduction may not be achieved if radioprotective curtains are folded. This study aimed to evaluate the scattered dose rate distribution and physician eye lens dose at different curtain lengths. Using an over-couch fluoroscopy system, dH*(10)/dt was measured using a survey meter 150 cm from the floor at 29 positions in the examination room when the curtain lengths were 0% (no curtain), 50%, 75%, and 100%. The absorbed dose rates in the air at the positions of endoscopist and assistant were calculated using a Monte Carlo simulation by varying the curtain length from 0 to 100%. The air kerma was measured by 10 min fluoroscopy using optically stimulated luminescence dosimeters at the eye surfaces of the endoscopist phantom and the outside and inside of the radioprotective goggles. At curtain lengths of 50%, 75%, and 100%, the ratios of dH*(10)/dt relative to 0% ranged from 80.8 to 104.1%, 10.5 to 61.0%, and 11.8 to 24.8%, respectively. In the simulation, the absorbed dose rates at the endoscopist's and assistant's positions changed rapidly between 55 and 75% and 65% and 80% of the curtain length, respectively. At the 0%, 50%, 75%, and 100% curtain lengths, the air kerma at the left eye surface of the endoscopist phantom was 237 ± 29, 271 ± 30, 37.7 ± 7.5, and 33.5 ± 6.1 µGy, respectively. Therefore, a curtain length of 75% or greater is required to achieve a sufficient eye lens dose reduction effect at the position of the endoscopist.

Basic characteristics of Vision badge and its performance as an eye lens dosimeter for endoscopists.

Vision badge is an eye lens dosimeter to measureHp(3). This study aimed to evaluate the basic characteristics of the Vision badge and its performance as an eye lens dosimeter for endoscopists by phantom study. Energy dependence was evaluated by changing the tube voltage to 50 kV (effective energy of 27.9 keV), 80 kV (32.2 keV), and 120 kV (38.7 keV). Dose linearity was evaluated by changing the number of irradiation to 1, 5, and 40 times, which corresponded to 0.53, 5.32, and 21.4 mGy. Batch uniformity was evaluated by calculating the coefficient of variation ofHp(3) obtained from 10 Vision badges. Angular dependence was evaluated at 0° (perpendicular to the incident direction of x-rays), 30°, 60°, 75°, and 90°. The Vision badge and optically stimulated luminescence (OSL) dosimeter were attached to the inside of the radioprotective glasses, worn on the endoscopist phantom, and theHp(3) obtained from both dosimeters were compared. TheHp(3) obtained from the Vision badge with 38.7 keV was 3.8% higher than that with 27.9 keV. The Vision badge showed excellent linearity (R2= 1.00) with the air kerma up to 21.4 mGy. The coefficient of variation of theHp(3) for 10 Vision badges was 3.47%. The relative dose of the Vision badge decreased as the angle increased up to 75°, but increased at 90°. TheHp(3) obtained by the OSL dosimeter and the Vision badge were decreased as the endoscopist phantom was turned away from the patient phantom. TheHp(3) that was obtained by the Vision badge was 35.5%-55.0% less than that obtained by the nanoDot. In conclusion, the Vision badge showed specific angular dependence due to its shape, but satisfactory basic properties were exhibited for all characteristics. In phantom study, the Vision badge showed generally similar trends with the OSL dosimeter.

Eye lens dose for medical staff assisting patients during computed tomography: comparison of several types of radioprotective glasses.

Medical staff sometimes assists patients in the examination room during computed tomography (CT) scans for several purposes. This study aimed to investigate the dose reduction effects of four radioprotective glasses with different lead equivalents and lens shapes. A medical staff phantom was positioned assuming body movement restraint of the patient during chest CT, and Hp(3) at the eye surfaces of the medical staff phantom and inside the lens of the four types of radioprotective glasses were measured by changing the distance of the staff phantom from the gantry, eye height, and width of the nose pad. The Hp(3) at the right eye surface with glasses of 0.50-0.75 mmPb and 0.07 mmPb was approximately 83.5% and 58.0%, respectively, lower than that without radioprotective glasses. The dose reduction rates at left eye surface increased with over-glass type glasses by 14%-28% by increasing the distance from the CT gantry to the staff phantom from 25 to 65 cm. The dose reduction rates at the left eye surface decreased with over-glass type glasses by 26%-31% by increasing the height of the eye lens for the medical staff phantom from 130 to 170 cm. The Hp(3) on the left eye surface decreased by 46.9% with the widest nose pad width compared to the narrowest nose pad width for the glasses with adjustable nose pad width. The radioprotective glasses for staff assisting patients during CT examinations should have a high lead equivalent and no gap around the nose and under the front lens.

Feasibility of a mobile cardiotocogram device for fetal heart rate self-monitoring in low-risk singleton pregnant women.

AIM: This study aimed to clarify the feasibility of a mobile cardiotocogram (CTG) device for self-monitoring fetal heart rate (FHR) in low-risk singleton pregnant women. METHODS: This study was conducted at six university hospitals and seven maternity clinics in Japan. Using a mobile cardiotocogram device (iCTG, Melody International Ltd., Kagawa, Japan), participants of more than 34 gestational weeks measured the FHR by themselves at least once a week until hospitalization for delivery. We evaluated the acquisition rate of evaluable FHR recordings and the frequency of abnormal FHR patterns according to the CTG classification system of the Japan Society of Obstetrics and Gynecology (JSOG). The participants also underwent a questionnaire survey after delivery to evaluate their satisfaction level of self-monitoring FHR using the mobile CTG device. RESULTS: A total of 1278 FHR recordings from 101 women were analyzed. Among them, 1276 (99.8%) were readable for more than 10 min continuously, and the median percentage of the total readable period in each recording was 98.9% (range, 51.4-100). According to the JSOG classification system, 1245 (97.6%), 9 (0.7%), 18 (1.4%), and four (0.3%) FHR patterns were classified as levels 1, 2, 3, and 4, respectively. The questionnaire survey revealed high participant satisfaction with FHR self-monitoring using the iCTG. CONCLUSION: The mobile CTG device is a feasible tool for self-monitoring FHR, with a high participant satisfaction level.

Maternal exposure to air pollutants during the first trimester and foetal growth in Japanese term infants.

Evidence supporting an inverse association between maternal exposure to air pollutants and foetal growth has been accumulating. However, the findings from Asian populations are limited, and the question of critical windows of exposure remains unanswered. We examined whether maternal exposure to air pollutants, in particular exposure during the first trimester (an important period of placental development), was associated with foetal growth in Japanese term infants. From the Japan Perinatal Registry Network database, we received birth data for 29,177 term singleton births in western Japan (Kyushu-Okinawa Districts) between 2005 and 2010. Exposure was expressed in terms of average concentrations of air pollutants (ozone, suspended particulate matter, nitrogen dioxide, and sulphur dioxide), as measured at the nearest monitoring stations to the respective delivery hospitals of the pregnant women, during the entire pregnancy and each trimester. As proxy markers of foetal growth restriction, we used small for gestational age (SGA), and adverse birth weight (low birth weight in addition to SGA). For pollutant exposure during the entire pregnancy, we did not observe the association with SGA and adverse birth weight. In the single-trimester model for the first trimester, however, we found a positive association between ozone exposure, and SGA (odds ratio [OR] per 10 ppb increase = 1.07, 95% confidence interval [CI] = 1.01-1.12) and adverse birth weight (OR = 1.07; 95% CI = 1.01-1.14). This association persisted in the multi-trimester model, and no association for exposure during the second or third trimester was observed. Exposure to other pollutants during each trimester was not associated with these outcomes. In conclusion, maternal exposure to ozone during the first trimester was independently associated with an elevated risk of poor foetal growth.

Air Pollutant Exposure Within a Few Days of Delivery and Placental Abruption in Japan.

BACKGROUND: Placental abruption is an emergency obstetric complication. Although the etiology of abruption is not fully understood, acute stimuli, such as ischemia and/or inflammation, are associated with rupture of the decidual artery, resulting in placental separation. Ischemia and inflammation are acute biologic effects of air pollution. Using a case-crossover design, we tested the hypothesis that a short-term increase in exposure to air pollutants is a potential trigger of placental abruption. METHODS: We received data for western Japan (Kyushu-Okinawa Districts) from the Japan Perinatal Registry Network database. From 2005 to 2010, 821 singleton pregnant women with placental abruption were identified. We assigned daily concentrations of air pollutants, including nitrogen dioxide (NO2), suspended particulate matter, ozone, and sulfur dioxide (SO2), from the nearest monitoring station to the respective delivery hospital of each woman. Because information on the onset day of abruption was not obtained, we assumed the case day to be 1 day before the day of delivery. RESULTS: Exposure to NO2 at 2 days' lag was associated with placental abruption (temperature adjusted odds ratio per 10 ppb increase = 1.4; 95% confidence interval = 1.1, 1.8). The association patterns were similar, when we restricted to participants who delivered by emergency cesarean (1.4, 1.1, 1.9), or who delivered after 35 weeks of gestation (1.4, 1.0, 2.0). There was no association with suspended particulate matter, ozone, or SO2. CONCLUSIONS: We observed an association between NO2 exposure at 2 days before the day of delivery and placental abruption in pregnant Japanese women.

Analysis of antenatal-onset cerebral palsy secondary to transient ischemia in utero using a national database in Japan.

AIM: We conducted a retrospective analysis of summary medical reports of children diagnosed with cerebral palsy (CP) to identify clinical features of antenatal onset of CP secondary to transient ischemia in utero. METHODS: The 658 brief summary reports available in the Japan Obstetric Compensation System for Cerebral Palsy were screened, and we identified cases of singleton pregnancy, delivered at gestational age ≥ 33 weeks and those with cord blood gas pH ≥ 7.20. Of the 137 cases identified, 84 were excluded for the following reasons: no evidence of ischemic brain lesion, clear post-natal causative factor of CP, presence of a congenital condition, and sentinel hypoxic event, such as uterine rupture. The demographic profiles of the 53 cases included in our analysis were compared to identify those with and without an abnormal variability in fetal heart rate. RESULTS: Between-group comparison identified an association between abnormal heart rate variability and a lower Apgar score at 1 min (2 vs 6; P < 0.001) and 5 min (5.5 vs 8; P = 0.002), and more frequent episodes of fetal movement loss (41% vs 10%; P = 0.027). An hypoxic event ≤ 1 week before delivery was more likely to be associated with abnormal heart rate variability (89%) and low Apgar score (82%), while events at > 1 week were associated with development of polyhydramnios (44%). CONCLUSION: In utero transient ischemic events can contribute to term or near-term CP. Careful follow-up is recommended for fetuses with a history of fetal movement loss, abnormal variability in heart rate, and polyhydramnios of unknown causes.

Exposure to air pollutants during the early weeks of pregnancy, and placenta praevia and placenta accreta in the western part of Japan.

BACKGROUND: Placenta praevia is an obstetric complication involving placental implantation in the lower uterine segment. Given the suggested aetiology of placenta praevia, adverse biological effects of air pollutants, such as plasma viscosity increment, endothelial dysfunction, and systemic inflammation, have the potential to induce low implantation. We explored the association between exposure to air pollutants during the pregnancy period up to implantation, and placenta praevia, in pregnant Japanese women. The outcome also included placenta accreta, which often exists in combination with placenta praevia. METHODS: From the Japan Perinatal Registry Network database, we obtained data on 40,573 singleton pregnant women in western Japan (Kyushu-Okinawa Districts) between 2005 and 2010. We assigned pollutant concentrations (suspended particulate matter [SPM], ozone, nitrogen dioxide [NO2], and sulphur dioxide [SO2]), measured at the nearest monitoring station to the respective delivery hospital of each woman. A logistic regression model was used to adjust for several covariates. RESULTS: The odds ratios (ORs) of placenta praevia per 10 units increase were 1.12 (95% confidence interval (CI)=1.01-1.23) for SPM over 0-4weeks of gestation, and 1.08 (1.00-1.16) for ozone. The association between exposure to NO2 and SO2, and praevia, was in the direction of increased risk. SPM exposure during 0-4weeks was associated with placenta accreta without praevia (OR=1.33, 95% CI=1.07-1.66). We found no association with exposure to air pollutants during 5-12weeks and the second trimester. CONCLUSIONS: Exposure to air pollutants through to implantation was positively associated with placenta praevia and accreta.

Fetal hydrocephalus and neonatal stroke as the first presentation of protein C deficiency.

Severe protein C-deficiency is a rare heritable thrombophilia of the newborn. Infants with biallelic PROC mutations present purpura fulminans and intracranial thromboembolism, while the prenatal onset of mutated heterozygotes remains unclear. We herewith present the first case of fetal ventriculomegaly and neonatal stroke associated with heterozygous PROC mutation. The infant was born to a healthy mother at 38 gestational weeks. The fetal growth had been normal, but the routine ultrasound screening had indicated mild hydrocephalus at 28 weeks of gestation. He developed convulsions two days after birth. Computed tomography of the brain revealed multiple hemorrhagic infarctions and ventriculomegaly. Dissociated levels of the plasma activity between protein C (21%) and protein S (42%) reached to determine the heterozygote of PROC c.574_576delAAG, a common thrombophilic predisposition in Asian ancestries. PC-mutant heterozygotes may have a limited high risk of cerebral thromboembolism during the perinatal course.

Maternal predictive factors for fetal congenital heart block in pregnant mothers positive for anti-SS-A antibodies.

OBJECTIVE: To determine the maternal predictive factors for fetal congenital heart block (CHB) in pregnancy in mothers positive for anti-SS-A antibodies. METHODS: The Research Team for Surveillance of Autoantibody-Exposed Fetuses and Treatment of Neonatal Lupus Erythematosus, the Research Program of the Japan Ministry of Health, Labor and Welfare, performed a national survey on pregnancy of mothers positive for anti-SS-A antibodies. We analyzed 635 pregnant mothers who tested positive for anti-SS-A antibodies before conception but had no previous history of fetal CHB. We performed univariate and multivariate analysis (models 1, 2, and 3 using different set of independent variables) investigated the relation between risk of fetal CHB and maternal clinical features. RESULTS: Of the 635 pregnant mothers, fetal CHB was detected in 16. Univariate analysis showed that fetal CHB associated with use of corticosteroids before conception (OR 3.72, p = 0.04), and negatively with use of corticosteroids (equivalent doses of prednisolone (PSL), at ≥10 mg/day) after conception before 16-week gestation (OR 0.17, p = 0.03). In multivariate analysis, model 1 identified the use of corticosteroids before conception (OR 4.28, p = 0.04) and high titer of anti-SS-A antibodies (OR 3.58, p = 0.02) as independent and significant risk factors, and model 3 identified use of corticosteroids (equivalent doses of PSL, at ≥10 mg/day) after conception before 16-week gestation as independent protective factor against the development of fetal CHB (OR 0.16, p = 0.03). Other maternal clinical features did not influence the development of fetal CHB. CONCLUSION: The results identified high titers of anti-SS-A antibodies and use of corticosteroids before conception as independent risk factors, and use of corticosteroids (equivalent doses of PSL, at ≥10 mg/day) after conception before 16-week gestation as an independent protective factor for fetal CHB.

A register-based study of the association between air pollutants and hypertensive disorders in pregnancy among the Japanese population.

BACKGROUND: Ambient air pollution is hypothesized to be a risk factor for hypertensive disorders in pregnancy, one of the major pregnancy complications. Past studies have reported the supporting evidence, however this mainly referred to the Western population, and results from trimester-specific analysis have been varied. In this study, we focused on exposure during the first trimester of pregnancy (placental development stage), and tested the hypothesis among the Japanese population. METHODS: We drew on data from the Japan Perinatal Registry Network database, and studied 36,620 singleton pregnant women without medical complications, in western Japan (Kyushu and Okinawa districts) between 2005 and 2010. In addition, data on ozone, suspended particulate matter (SPM), nitrogen dioxide (NO2), and sulfur dioxide (SO2) concentrations were obtained. The nearest monitoring station to the respective birthing hospital was used as a reference point for assigning average concentrations of each pollutant during the first trimester of pregnancy for each woman. The logistic regression model was applied to assess the association between quintiles of each pollutant and hypertensive disorders in pregnancy. RESULTS: Mean concentrations during the first trimester were 41.3 ppb for ozone, 27.4 µg/m(3) for SPM, 11.8 ppb for NO2, and 3.2 ppb for SO2. High exposure to ozone was associated with an increased risk of hypertensive disorders in pregnancy (for highest quintile vs. lowest: odds ratio=1.20, 95% confidence interval=1.01-1.42). With regard to SPM, NO2 and SO2, we did not obtain the results with constant directionality. CONCLUSIONS: Ozone exposure during early pregnancy may be a risk factor for hypertensive disorders in pregnancy.

Placental elasticity evaluation using virtual touch tissue quantification during pregnancy.

INTRODUCTION: Virtual touch tissue quantification (VTTQ) has been developed to evaluate tissue elasticity. Our previous study using delivered placentas showed increased elasticity in fetal growth restriction (FGR). Therefore, we investigated changes in placental elasticity during pregnancy, including complicated pregnancies. METHODS: Based on complications, 199 women were divided into 5 groups (normal, FGR, pregnancy induced hypertension (PIH), diabetes mellitus and collagen disease), and shear wave velocity (SWV) of the placenta, measured using VTTQ, was compared. A cross-sectional study was performed with the 143 normal cases to construct the reference range. The association between placental SWV and the expression ratio of collagen fibers in the placenta stained with Masson's trichrome was determined. RESULTS: The SWV was safely measured for all participants. The correlation between SWV and gestational weeks was not significant. The mean ± SD SWVs in the normal, FGR, and PIH groups were 0.98 ± 0.21, 1.28 ± 0.39, and 1.60 ± 0.45 m/sec, respectively. The FGR and PIH groups had significantly higher SWVs than that of the normal group. SWV and the expression ratio of collagen fibers were significantly correlated. DISCUSSION: Based on the present findings, changes in SWV during pregnancy were associated with placental fibrosis, and increased SWV in PIH and/or FGR cases might be influenced by infarction, ischemic changes, and inflammation, as well as fibrosis. In conclusion, the measurement of placental SWV is potentially useful to evaluate the condition of the placenta during pregnancy.

External iliac artery thrombosis after common iliac artery balloon occlusion during cesarean hysterectomy for placenta accreta in cervico-isthmic pregnancy.

Although the role of interventional radiology in the field of obstetrical hemorrhage has been widely reported upon recently, the rate of procedure-related complications has not been fully determined. We present the case of a patient who developed an external iliac artery thrombosis, a rarely reported complication associated with prophylactic common iliac artery balloon occlusion (CIABO). After CIABO, we found that the dorsalis pedis artery of the right foot was weak and the foot was cold, despite the fact that the patient had no complaints. Computed tomography demonstrated a linear thrombus in the right external iliac artery. We managed the patient conservatively using a heparin drip without the need for thromboembolectomy. Our experience suggests that it is important to consider the risk of thrombosis formation after CIABO. Physical examination post-procedure is key to identifying this complication early.

Neurological outcomes in Chiari type II malformations and their correlation to morphological findings and fetal heart rate patterns: a retrospective study.

BACKGROUND: Correlations among Chiari type II malformation (CMII) morphological findings, the proportion of fetal heart rate patterns corresponding to the quiet phase (QP), and neurological outcomes have yet to be investigated. FINDINGS: The correlations among the morphological findings (i.e., the degree of ventriculomegaly, myelomeningocele levels, and degree of cerebellar herniation), proportion of time spent in QP, and developmental quotients (DQs) were analyzed in 22 children. The proportion of time spent in QP was compared between children with poor neurological outcomes (n = 9) and those with good outcomes (n = 13). Pearson's correlations and the Mann-Whitney U-test were used to assess for statistical significance; P < 0.05 was considered statistically significant. No significant differences were observed between the DQs and morphological findings, but the DQs and the proportion of time spent in QP were significantly correlated (r = 0.287, P = 0.01). The proportion of time spent in QP was significantly different between children with poor outcomes and those with good outcomes (median, 11% [range, 0-32%] vs. 28% [range, 2-55%]; P = 0.006). CONCLUSIONS: The proportion of fetal heart rate patterns corresponding to the QP might be a useful predictor of neurological outcomes in 2-year-old children with CMII.

Fetal cytomegalovirus infection manifesting as transient pancytopenia.

We encountered a patient with a fetal cytomegalovirus infection manifesting as pancytopenia and thoracic hypoplasia. The fetal anemia was treated by transfusion via the umbilical cord, and did not progress after 22 weeks' gestation. The neutropenia resolved spontaneously, and only thrombocytopenia was persistent at birth. The severe thoracic hypoplasia led to pulmonary hypertension and required intensive postnatal respiratory management. Our experience suggests that pancytopenia is a possible manifestation in fetuses infected with cytomegalovirus. This may be transient, resolving spontaneously during fetal life; however, caution should be taken with blood counts, particularly platelet counts, after delivery. In addition, clinicians should carefully follow the thoracic volume in cytomegalovirus-infected fetuses and consider the possibility of postnatal severe respiratory insufficiency.

Spontaneous post-partum rupture of an ovarian artery aneurysm: a case report of successful embolization and a review of the published work.

It is rare for an ovarian artery aneurysm to rupture during the peripartum period, but the outcome can be catastrophic. Between 1980 and 2013, only nine cases have been reported in the English-language medical published work. We describe a patient with a left ovarian artery aneurysm that ruptured 4 days after an uneventful vaginal delivery. The rupture was immediately identified, using emergent computed tomography and angiography. The hemorrhage was managed using arterial embolization and blood transfusion, allowing for a successful outcome. The possibility of ruptured ovarian artery aneurysm should be considered in the differential diagnosis for women with excessive or localized abdominal pain after childbirth.

Rare fetal complications associated with placental mesenchymal dysplasia: a report of two cases.

Placental mesenchymal dysplasia (PMD) is a rare disease that may be difficult to distinguish from molar pregnancy. The disease is associated with major fetal complications, including Beckwith-Wiedemann syndrome, fetal growth restriction and intrauterine fetal death. Rarely, fetal hematological disorders and liver tumors also may occur. Two patients were referred to our hospital during their second trimesters because of suspected molar pregnancies. Fetal karyotyping and maternal serum human chorionic gonadotropin level determinations led to the PMD diagnoses. In one case, the maternal clinical course was normal, but the neonate suffered from disseminated intravascular coagulation and needed a platelet transfusion. In the second case, the PMD decreased during pregnancy, but a gradually increasing fetal liver tumor appeared. The tumor was diagnosed as mesenchymal hamartoma, based on ultrasound and magnetic resonance imaging studies. The neonate was delivered without cardiovascular compromise. Due to the difficulty of immediate surgical treatment, expectant management, with close follow-up, was chosen.

Can we predict neonatal thrombocytopenia in offspring of women with idiopathic thrombocytopenic purpura?

BACKGROUND: We aimed to investigate which factors in the clinical profile of mothers with idiopathic thrombocytopenic purpura (ITP) can predict neonatal risk of thrombocytopenia. METHODS: Data was retrospectively collected from all pregnant women with ITP who presented to our institution between 2001 and 2013. Neonatal offspring of these women were classified into 2 groups based on the presence or absence of neonatal thrombocytopenia (platelet count <100×10(9)/L). Several parameters were compared between the 2 groups, including maternal age, maternal platelet count, maternal treatment history, and thrombocytopenia in siblings. We further examined the correlation between maternal platelet count at the time of delivery and neonatal platelet count at birth; we also examined the correlation between the minimum platelet counts of other children born to multiparous women. RESULTS: Sixty-six neonates from 49 mothers were enrolled in the study. Thrombocytopenia was observed in 13 (19.7%) neonates. Maternal treatment for ITP such as splenectomy did not correlate with a risk of neonatal thrombocytopenia. Sibling thrombocytopenia was more frequently observed in neonates with thrombocytopenia than in those without (7/13 vs. 4/53, P<0.01). No association was observed between maternal and neonatal platelet counts. However, the nadir neonatal platelet counts of first- and second-born siblings were highly correlated (r=0.87). CONCLUSION: Thrombocytopenia in neonates of women with ITP cannot be predicted by maternal treatment history or platelet count. However, the presence of an older sibling with neonatal thrombocytopenia is a reliable risk factor for neonatal thrombocytopenia in subsequent pregnancies.