Diffusion-weighted MR imaging of the placenta in fetuses with placental insufficiency

PURPOSE: To evaluate diffusion-weighted magnetic resonance (MR) imaging of the human placenta in fetuses with and fetuses without intrauterine growth restriction (IUGR) who were suspected of having placental insufficiency. MATERIALS AND METHODS: The study was approved by the local ethics committee, and written informed consent was obtained. The authors retrospectively evaluated 1.5-T fetal MR images from 102 singleton pregnancies (mean gestation ± standard deviation, 29 weeks ± 5; range, 21-41 weeks). Morphologic and diffusion-weighted MR imaging were performed. A region of interest analysis of the apparent diffusion coefficient (ADC) of the placenta was independently performed by two observers who were blinded to clinical data and outcome. Placental insufficiency was diagnosed if flattening of the growth curve was detected at obstetric ultrasonography (US), if the birth weight was in the 10th percentile or less, or if fetal weight estimated with US was below the 10th percentile. Abnormal findings at Doppler US of the umbilical artery and histopathologic examination of specimens from the placenta were recorded. The ADCs in fetuses with placental insufficiency were compared with those in fetuses of the same gestational age without placental insufficiency and tested for normal distribution. The t tests and Pearson correlation coefficients were used to compare these results at 5% levels of significance. RESULTS: Thirty-three of the 102 pregnancies were ultimately categorized as having an insufficient placenta. MR imaging depicted morphologic changes (eg, infarction or bleeding) in 27 fetuses. Placental dysfunction was suspected in 33 fetuses at diffusion-weighted imaging (mean ADC, 146.4 sec/mm(2) ± 10.63 for fetuses with placental insufficiency vs 177.1 sec/mm(2) ± 18.90 for fetuses without placental insufficiency; P < .01, with one false-positive case). The use of diffusion-weighted imaging in addition to US increased sensitivity for the detection of placental insufficiency from 73% to 100%, increased accuracy from 91% to 99%, and preserved specificity at 99%. CONCLUSION: Placental dysfunction associated with growth restriction is associated with restricted diffusion and reduced ADC. A decreased ADC used as an early marker of placental damage might be indicative of pregnancy complications such as IUGR.

Impact of renal insufficiency on clinical outcomes in patients with critical limb ischemia undergoing endovascular revascularization

Patients with renal insufficiency (RI) are frequently excluded from trials assessing various endovascular revascularization concepts in critical limb ischemia (CLI) although information on clinical outcomes is scarce.

Adrenal insufficiency after glucocorticoid withdrawal in children with rheumatic diseases

?Glucocorticoids (GCs) are often used for the treatment of rheumatic disorders. However, doses are prescribed, which may suppress the hypothalamic-pituitary-adrenal (HPA) axis. After GC withdrawal, recovery of the HPA axis may be delayed putting the patient at risk for adrenal insufficiency. We assessed adrenal function and factors influencing adrenal responsiveness after termination of GC therapy in paediatric patients with rheumatic diseases.

Survival benefits of revascularization in patients with critical limb ischemia and renal insufficiency

Evidence for the best treatment strategy for patients with critical limb ischemia (CLI) at different stages of renal insufficiency (RI) is rare. Therefore, we determined the benefit of revascularization vs medical therapy (MT) only in CLI patients with different levels of RI.

Distinctive Convergence in Australian Floral Colours Seen Through the Eyes of Australian Birds

We used a colour-space model of avian vision to assess whether a distinctive bird pollination syndrome exists for floral colour among Australian angiosperms. We also used a novel phylogenetically based method to assess whether such a syndrome represents a significant degree of convergent evolution. About half of the 80 species in our sample that attract nectarivorous birds had floral colours in a small, isolated region of colour space characterized by an emphasis on long-wavelength reflection. The distinctiveness of this 'red arm' region was much greater when colours were modelled for violet-sensitive (VS) avian vision than for the ultraviolet-sensitive visual system. Honeyeaters (Meliphagidae) are the dominant avian nectarivores in Australia and have VS vision. Ancestral state reconstructions suggest that 31 lineages evolved into the red arm region, whereas simulations indicate that an average of five or six lineages and a maximum of 22 are likely to have entered in the absence of selection. Thus, significant evolutionary convergence on a distinctive floral colour syndrome for bird pollination has occurred in Australia, although only a subset of bird-pollinated taxa belongs to this syndrome. The visual system of honeyeaters has been the apparent driver of this convergence.

Ten novel mutations in the NR5A1 gene cause disordered sex development in 46,XY and ovarian insufficiency in 46,XX individuals

Steroidogenic factor-1 (SF-1/NR5A1) is a nuclear receptor that regulates adrenal and reproductive development and function. NR5A1 mutations have been detected in 46,XY individuals with disorders of sexual development (DSD) but apparently normal adrenal function and in 46,XX women with normal sexual development yet primary ovarian insufficiency (POI).

Efficiency and safety of bosentan in child C cirrhosis with portopulmonary hypertension and renal insufficiency

Bosentan has lately been described as a successful therapeutic agent for portopulmonary hypertension consecutive to child A cirrhosis. This is the first report of the effect of this substance with advanced liver cirrhosis (child C) and renal insufficiency. Low doses of bosentan (initially twice 31.25 mg/day and then 62.5 mg/day) increased cardiac output and allowed correction of renal insufficiency; it allowed one to stop the requirement of oxygen and not only improved the 6-min walking test by more than 400 m, but also decreased the severity of the liver cirrhosis to child B stadium. This suggests that patients, who would be excluded from a liver transplantation program because of their portopulmonary hypertension, could profit from a careful therapy with bosentan.