Rapid reconstruction of highly undersampled,non‐Cartesian real‐time cine k‐space data using a perceptual complex neural network (PCNN)

Highly accelerated real‐time cine MRI using compressed sensing (CS) is a promising approach to achieve high spatio‐temporal resolution and clinically acceptable image quality in patients with arrhythmia and/or dyspnea. However, its lengthy image reconstruction time may hinder its clinical translation. The purpose of this study was to develop a neural network for reconstruction of non‐Cartesian real‐time cine MRI k‐space data faster (<1 min per slice with 80 frames) than graphics processing unit (GPU)‐accelerated CS reconstruction, without significant loss in image quality or accuracy in left ventricular (LV) functional parameters. We introduce a perceptual complex neural network (PCNN) that trains on complex‐valued MRI signal and incorporates a perceptual loss term to suppress incoherent image details. This PCNN was trained and tested with multi‐slice, multi‐phase, cine images from 40 patients (20 for training, 20 for testing), where the zero‐filled images were used as input and the corresponding CS reconstructed images were used as practical ground truth. The resulting images were compared using quantitative metrics (structural similarity index (SSIM) and normalized root mean square error (NRMSE)) and visual scores (conspicuity, temporal fidelity, artifacts, and noise scores), individually graded on a five‐point scale (1, worst; 3, acceptable; 5, best), and LV ejection fraction (LVEF). The mean processing time per slice with 80 frames for PCNN was 23.7 ± 1.9 s for pre‐processing (Step 1, same as CS) and 0.822 ± 0.004 s for dealiasing (Step 2, 166 times faster than CS). Our PCNN produced higher data fidelity metrics (SSIM = 0.88 ± 0.02, NRMSE = 0.014 ± 0.004) compared with CS. While all the visual scores were significantly different (P < 0.05), the median scores were all 4.0 or higher for both CS and PCNN. LVEFs measured from CS and PCNN were strongly correlated (R² = 0.92) and in good agreement (mean difference = ?1.4% [2.3% of mean]; limit of agreement = 10.6% [17.6% of mean]). The proposed PCNN is capable of rapid reconstruction (25 s per slice with 80 frames) of non‐Cartesian real‐time cine MRI k‐space data, without significant loss in image quality or accuracy in LV functional parameters.     

Administration of recombinant human erythropoietin in patients with gynecological cancer before radical surgery

The purpose of this prospective study was to investigate the efficacy of preoperative administration of recombinant human erythropoietin in patients with gynecological cancer. METHODS: The study included 38 women with gynecological cancer who were divided randomly in two groups. Study group A included 20 women with gynecological cancer who received recombinant human erythropoietin (rHuEPO) plus iron supplementation for ten days before surgery and five days postoperatively. Group B (controls) included 18 patients who received only iron supplementation for the same time period. Blood samples were obtained on days -10, -3, 0, +3, +5, +10. RESULTS: The mean hemoglobin level was significantly higher in group A than in group B on the day of the operation and remained significantly higher postoperatively while an inverse relationship was observed for mean ferritin values in the two groups. CONCLUSION: Preoperative administration of rHuEPO in patients with gynecological cancer seems to be effective in the blood management of these patients.     

Maternal prolactin secretion during labor. The role of dopamine

BACKGROUND: To investigate the role of dopamine on the mechanisms of maternal prolactin secretion during labor and in the first six hours following delivery. METHODS: The study included 30 pregnant women with normal pregnancies, who were meeting the same criteria. They were divided into three subgroups of 10 patients each and they delivered healthy newborns. Group A was the control group. Metoclopramide 10 mg/h intravenously was given in Group B, while bromocryptine 5 mg per os was given in Group C. Maternal blood samples were obtained every hour during labor and in the six hours postpartum. Prolactin values were determined by using a radioimmunoassay method. RESULTS: Metoclopramide infusion caused an initial significant (p<0.01) rise in PRL level in Group B. Prolactin levels showed the same multiphasic pattern during labor and first h postpartum in both Groups A and B. PRL levels decreased until 1-2 h antepartum, then increased for about 3 h and they finally decreased, starting at 2 h postpartum and reaching values lower than the basic at 6 h postpartum. However, absolute PRL values were higher in Group B (where metoclopramide was given) than in Group A, in every time point. Bromocryptine (Group C) markedly lowered PRL levels, but PRL fluctuation still followed the same trends as in the other two groups. CONCLUSIONS: The different PRL values between the three groups show that maternal PRL is still under dopaminergic influence during labor. However, the fact that PRL levels exhibit the same multiphasic pattern, suggests that there are factors other than dopamine, which strongly influence this pattern.     

Noninvasive diagnosis by Doppler ultrasonography of fetal anemia resulting from parvovirus infection

OBJECTIVE: The purpose of this study was to evaluate the feasibility of the middle cerebral artery peak systolic velocity for the detection of fetal anemia in pregnancies that are complicated by parvovirus B19 infection. STUDY DESIGN: Doppler measurements of the middle cerebral artery peak systolic velocity were performed weekly in 32 fetuses at risk for anemia because of maternal parvovirus infection documented by the presence of serum immunoglobulin M antibody. The values of the middle cerebral artery peak systolic velocity and hemoglobin were expressed as multiples of the median. These values were plotted on reference ranges that had been established previously. A cordocentesis was performed either because of fetal ascites or when the middle cerebral artery peak systolic velocity values suggested anemia (middle cerebral artery peak systolic velocity, >1.50 multiples of the median). RESULTS: Gestational age at study entry ranged from 15.1 to 37 weeks. There were 17 fetuses with middle cerebral artery peak systolic velocity of >1.50 MoM (group 1). Sixteen cordocenteses were performed in these fetuses. All 16 fetuses were anemic (15 severely and 1 mildly). Thirteen fetuses had signs of hydrops (12 with severe and 1 with mild anemia). Group 2 included 15 fetuses with the middle cerebral artery peak systolic velocity values <1.50 MoM. Two cordocenteses were performed. One fetus was mildly anemic; the second fetus was not anemic. The remaining 13 fetuses of this group did not have any complications and were not anemic at birth. The sensitivity of the middle cerebral artery peak systolic velocity (>1.50 MoM) for the prediction of anemia because of parvovirus infection was 94.1%; the specificity was 93.3 %; the positive and negative predictive values were 94.1% and 93.3%, respectively. CONCLUSION: Fetal anemia caused by parvovirus infection can be detected noninvasively by Doppler ultrasonography on the basis of an increase in the peak velocity of systolic blood flow in the middle cerebral artery.     

Individual growth curve standards in twins: prediction of third-trimester growth and birth characteristics

The ability of Rossavik growth models, determined from measurements obtained before 24 weeks, to predict third-trimester growth and birth characteristics in normally growing twins has been investigated. Third-trimester values for head circumference, abdominal circumference, and femur diaphysis length were predicted with an accuracy of +/- 6% to 9% (95% to 98% of percent deviations). For thigh circumference and estimated weight, the comparable values were +/- 15% and +/- 16%, respectively. The head circumference at birth was predicted without bias; the random error was approximately +/- 5% (94% of percent differences). Weight, abdominal circumference, and thigh circumference were systematically overestimated (3.1%, 14.9%, and 11.3%, respectively) as a result of differences in prenatal and postnatal measurement procedures. After correction for systematic errors, these parameters could be predicted with random errors of -11.5% to 7.2% (weight), -12.8% to 5.4% (abdominal circumference), and -15.3% to 10.0% (thigh circumference). Growth Potential Realization Index values were found to have means of approximately 100% and ranges from 91% to 118%. These results are similar to those for singletons and indicate that individual assessment of growth in twins can be carried out with the same methods used for singletons.     

A dimensional impulsive-aggressive phenotype is associated with the A218C polymorphism of the tryptophan hydroxylase gene: a pilot study in well-characterized impulsive inpatients

Tryptophan hydroxylase (TPH) is the rate-limiting enzyme in the biosynthesis of serotonin, and association and linkage studies of its variants in suicidal and impulsive-aggressive behavior have brought conflicting results. This pilot study was designed to investigate whether TPH A218C genotypes could be associated with impulsive behavioral tendencies (IBTs) in consecutively admitted nonpsychotic nonorganic inpatients. Patients (20 females and 34 males; age, 38.8 +/- 11.8) did not differ from healthy nonimpulsive controls (16 females and 11 males; age, 35.2 +/- 10.2) regarding TPH genotypes, but in the patients, the number of IBT was related to the presence of the 218C allele. It was concluded that impulsive-aggressive behavior may be associated with the TPH genotype in well-characterized impulsive patients and that the present results stress the importance of considering impulsiveness-aggressiveness in studies investigating the relationship between suicidal behavior and TPH genotypes.     

A dimensional impulsive‐aggressive phenotype is associated with the A218C polymorphism of the tryptophan hydroxylase gene: A pilot study in well‐characterized impulsive inpatients

Tryptophan hydroxylase (TPH) is the rate‐limiting enzyme in the biosynthesis of serotonin, and association and linkage studies of its variants in suicidal and impulsive‐aggressive behavior have brought conflicting results. This pilot study was designed to investigate whether TPH A218C genotypes could be associated with impulsive behavioral tendencies (IBTs) in consecutively admitted nonpsychotic nonorganic inpatients. Patients (20 females and 34 males; age, 38.8 ± 11.8) did not differ from healthy nonimpulsive controls (16 females and 11 males; age, 35.2 ± 10.2) regarding TPH genotypes, but in the patients, the number of IBT was related to the presence of the 218C allele. It was concluded that impulsive‐aggressive behavior may be associated with the TPH genotype in well‐characterized impulsive patients and that the present results stress the importance of considering impulsiveness‐aggressiveness in studies investigating the relationship between suicidal behavior and TPH genotypes. © 2002 Wiley‐Liss, Inc.