Temperature influences upon vascular dynamics in cattle measured by Doppler ultrasonography

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Doppler-image ultrasonography was used to document vascular changes and blood flow rates of cattle (Bos taurus) under hot (32.7 °C) and cold (8.1 °C) conditions for 24 h.     

Evaluation of bovine luteal blood flow by using color Doppler ultrasonography

Since luteal vascularization plays a decisive role for the function of the corpus luteum (CL), the investigation of luteal blood flow (LBF) might give valuable information about the physiology and patho-physiology of the CL. To quantify LBF, usually Power mode color Doppler ultrasonography is used. This method detects the number of red blood cells moving through the vessels and shows them as color pixels on the B-mode image of the CL. The area of color pixels is measured with computer-assisted image analysis software and is used as a semiquantitative parameter for the assessment of LBF. Although Power mode is superior for the evaluation of LBF compared to conventional color Doppler ultrasonography, which detects the velocity of blood cells, it is still not sufficiently sensitive to detect the blood flow in the small vessels in the center of the bovine CL. Therefore, blood flow can only be measured in the bigger luteal vessels in the outer edge of the CL. Color Doppler ultrasonographic studies of the bovine estrous cycle have shown that plasma progesterone (P4) concentration can be more reliably predicted by LBF than by luteal size (LS), especially during the CL regression. During the midluteal phase, cows with low P4 level showed smaller CL, but LBF, related to LS, did not differ between cows with low and high P4 levels. In contrast to non-pregnant cows, a significant rise in LBF was observed three weeks after insemination in pregnant cows. However, LBF was not useful for an early pregnancy diagnosis due to high LBF variation among cows. When the effects of an acute systemic inflammation and exogenous hormones on the CL are examined, the LBF determination is more sensitive than LS assessment. In conclusion, color Doppler ultrasonography of the bovine CL provides additional information on luteal function compared to measurements of LS and plasma P4, but its value as a parameter concerning assessment of fertility in cows has to be clarified.     

Neonatal outcome of fetuses with urinary tract abnormalities diagnosed by prenatal ultrasonography.

Between 1979 and 1986 an abnormality of the urinary tract was diagnosed by prenatal ultrasound examination in 93 fetuses. Postnatal investigation at a large teaching hospital showed a definite abnormality in 85 infants, 66 of whom were boys. An obstructed urinary tract, usually requiring surgery, was present in 46 infants. Other abnormalities included a multicystic kidney (in 15 infants), vesicoureteric reflux (in 9), prune-belly syndrome (in 5) and polycystic kidneys (in 5). Early recognition and treatment of urinary tract disorders in infants should be accompanied by informed prenatal counselling to minimize parents'' anxiety.     

Radiology: color Doppler ultrasonography of the liver

The Scientific Board of the California Medical Association presents the following inventory of items of progress in radiology. Each item, in the judgment of a panel of knowledgeable physicians, has recently become reasonably firmly established both as to scientific fact and important clinical significance. The items are presented in simple epitome and an authoritative reference, both to the item itself and to the subject as a whole, is generally given for those who may be unfamiliar with a particular item. The purpose is to assist busy practitioners, students, research workers, or scholars to stay abreast of these items of progress in radiology that have recently achieved a substantial degree of authoritative acceptance, whether in their own field of special interest or another.The items of progress listed below were selected by the Advisory Panel to the Section on Radiology of the California Medical Association, and the summaries were prepared under its direction.     

Power Doppler improves the diagnostic accuracy of color Doppler ultrasonography in cold thyroid nodules: follow-up results

The usefulness of a recent color Doppler (CD) ultrasonography technique, named power Doppler (PD), was evaluated in the diagnosis of thyroid nodules showing low or absent uptake of (99m)Tc-pertechnetate, in order to investigate the possibility to improve the diagnostic accuracy of ultrasonography. The rationale was the evidence that at PD the color map displays the total integrated Doppler power in color, while CD generally displays an estimate of the mean Doppler shift. The vascular patterns recorded at PD and CD evaluation of 322 thyroid nodules were compared to the results of cytology and/or histology, when surgery was performed. In respect to the results of cytology, PD has a higher sensitivity (100 vs. 91%) and specificity (95.1 vs. 86.2%) than CD. A similar result was found when PD and CD were compared to the results of histology, sensitivity being 100 vs. 89% and specificity 98.1 vs. 93.7%, respectively. During the follow-up the 2 nodules considered false positive at PD resulted to be tumoral lesions. On this basis, the final specificity of PD in our series was 100%. In conclusion, in the current series including 322 thyroid nodules characterized by a low or absent uptake of (99m)Tc-pertechnetate, PD seems to provide a better characterization of thyroid nodules, possibly allowing a more accurate selection of the patients to subject to fine-needle biopsy.     

Assessment of feline fetal viability by conceptus echobiometry and triplex Doppler ultrasonography of uterine and umbilical arteries

The aims of the present study were to: (1) evaluate blood flow in the uterine (UA) and umbilical arteries (Uma) in the pregnant queen, by measuring the resistive index (RI) and pulsatility index (PI); (2) to note the presence or absence of the early diastolic notch and diastolic flow in the UA and Uma flow waveforms, respectively; and (3) perform conceptus echobiometry for fetal growth assessment during pregnancy. Eight healthy pregnant domestic Brazilian Shorthair queens were examined from Days 10 to 50 after mating (mating=Day 0). Triplex Doppler and B-mode ultrasonography were used to assess blood flow and conceptus echobiometry. All pregnancies ended with a normal parturition and birth of live kittens. Prior to parturition, all conceptus dimensions increased significantly, whereas RI and PI peaked between Days 33 and 43 followed by a decrease (P<0.05). The PI least on Day 50. The RI and PI of Uma decreased (P<0.05) during two periods in the fetal development, i.e. from Days 22 to 40 (0.79 ± 0.01 and 1.64 ± 0.04), and from Days 41 to 50 (0.75 ± 0.01 and 1.39 ± 0.05), representing the increased Uma perfusion. Both the complete disappearance of the early diastolic notch in the UA, and the appearance of diastolic flow in the Uma occurred on Day 42 ± 1. It was concluded fetal echobiometry, UA and Uma perfusion, were important end points to assess fetal viability in queens. Furthermore, the current reference values provided a baseline for monitoring normal and abnormal pregnancies in queens.     

Splenogonadal Fusion: An Unusual Case of an Acute Scrotum

We highlight a case on a normal left testicle with a fibrovascular cord with three nodules consistent with splenic tissue. The torsed splenule demonstrated hemorrhage with neutrophilic infiltrate and thrombus consistent with chronic infarction and torsion. Splenogonadal fusion (SGF) is a rather rare entity, with approximately 184 cases reported in the literature. The most comprehensive review was that of 123 cases completed by Carragher in 1990. Since then, an additional 61 cases have been reported in the scientific literature. We have studied these 61 cases in detail and have included a summary of that information here.Key words: Splenogonadal fusion, Acute scrotumA 10-year-old boy presented with worsening left-sided scrotal pain of 12 hours’ duration. The patient reported similar previous episodes occurring intermittently over the past several months. His past medical history was significant for left hip dysplasia, requiring multiple hip surgeries. On examination, he was found to have an edematous left hemiscrotum with a left testicle that was rigid, tender, and noted to be in a transverse lie. The ultrasound revealed possible polyorchism, with two testicles on the left and one on the right (Figure 1), and left epididymitis. One of the left testicles demonstrated a loss of blood flow consistent with testicular torsion (Figure 2).Open in a separate windowFigure 1Ultrasound of the left hemiscrotum reveals two spherical structures; the one on the left is heterogeneous and hyperdense in comparison to the right.Open in a separate windowFigure 2Doppler ultrasound of left hemiscrotum. No evidence of blood flow to left spherical structure.The patient was taken to the operating room for immediate scrotal exploration. A normalappearing left testicle with a normal epididymis was noted. However, two accessory structures were noted, one of which was torsed 720°; (Figure 3). An inguinal incision was then made and a third accessory structure was noted. All three structures were connected with fibrous tissue, giving a “rosary bead” appearance. The left accessory structures were removed, a left testicular biopsy was taken, and bilateral scrotal orchipexies were performed.Open in a separate windowFigure 3Torsed accessory spleen with splenogonadal fusion.Pathology revealed a normal left testicle with a fibrovascular cord with three nodules consistent with splenic tissue. The torsed splenule demonstrated hemorrhage with neutrophillic infiltrate and thrombus consistent with chronic infarction and torsion (Figure 4).Open in a separate windowFigure 4Splenogonadal fusion, continuous type with three accessory structures.     

Transcranial Doppler ultrasonography: stereotactically guided examinations using magnetic resonance angiography]

The accurate localization of specific intracranial blood vessels is a major difficulty with transcranial Doppler sonography (TCD). It was the purpose of this study to develop a system enabling stereotactic navigation during a TCD examination on the basis of high-resolution three-dimensional magnetic resonance angiographic (MRA) data. During TCD, the examiner is provided--on a computer screen--with a projected view of the respective intracranial vessel anatomy. With the aid of an optoelectronic localization system, the spatial orientation and localization of the US probe is determined in real time, and correlated with the patient's MRA data using a dedicated stereotactic mask. Subsequently, the US beam and the points of insonation are displayed on the screen overlaid on the vessel anatomy. In this way the examiner gains real time control of the localization of the respective intracranial vessel insonated. Points of insonation can be stored and recalled for follow-up examinations. In addition to the successful verification of the system, it was shown that, in comparison with conventional TCD, stereotactic navigation distinctly improves the reproducibility of repeat TCD examinations.     

Antenatal screening for intrauterine growth retardation with umbilical artery Doppler ultrasonography.

To assess the usefulness of continuous wave Doppler ultrasonography as an antenatal screening tool for the detection of intrauterine growth retardation and fetal compromise 2097 singleton pregnancies were studied. Umbilical artery velocity waveforms were obtained at 28, 34, and 38 weeks of gestation, from which the pulsatility index, A/B ratio, and resistance parameter were calculated. No abnormal features or indices of neonatal outcome were adequately predicted. The most sensitive index for being delivered of a growth retarded infant (less than 5th centile birth weight for gestation) was an A/B ratio at 34 weeks (sensitivity 40%, specificity 84%). Other measures that show poor neonatal nutritional state (ponderal index, skinfold thickness, and ratio of mid-arm circumference to head circumference) were even less well predicted. Acute and chronic hypoxia as determined by Apgar score, pH in blood from the cord artery, and packed cell volume correlated poorly with umbilical artery waveform indices, and there was no obvious difference between the indices of those who subsequently required operative or instrumental delivery for fetal distress and those requiring no intervention. There were three unexplained stillbirths in the series, in each of which the fetus had shown waveform patterns that suggested increased peripheral resistance, though the technique did not appear to be useful for predicting the time of subsequent death. Screening for small for dates babies in a three stage programme was of no value regardless of the threshold or index chosen. Obstetricians should resist the temptation to introduce screening with Doppler ultrasonography until its proper role has been determined.     

Measurement of cerebral blood flow by transcranial Doppler ultrasonography in children presenting with autistic behavior. Preliminary results

Transcranial Doppler ultrasonographic recordings of the middle cerebral arteries were performed on eight children with autistic behavior compared to eight controls. Blood flow measurements were assessed at rest and during auditory and visual stimulations. The main result was obtained during the auditory stimulations and concerned the left artery blood flow which is lower in autistics than in controls in these conditions (p less than .02). This result confirms the possibility of a left hemisphere dysfunctioning in autistics and may be related to clinical features as language disabilities and paradoxical reactivity to auditory stimuli.     

Non-invasive translational Cynomolgus model for studying folliculogenesis and ovulation using color Doppler ultrasonography

Background In women, different events of folliculogenesis can be measured and evaluated using ultrasound (US) technology. The availability of a non‐invasive translational non‐human primate model to study these processes would represent a major contribution to further advance R&D efforts toward novel therapies in assisted reproduction. Methods In our study, follicular growth and ovulation was measured in six cyclic Cynomolgus monkeys using abdominal Doppler US. Results The mean follicular diameter on cycle day ?6 (cycle day 0 = day of ovulation) was 3.7 mm that increased to 6.8 mm on cycle day ?1. After ovulation, the mean diameter decreased to 4.6 mm, confirming ovulation. The mean percentage of follicular size reduction after ovulation was 31%. Conclusion Ultrasonography in combination with color‐flow Doppler imaging was shown to be a useful, non‐invasive translational method to measure ovarian follicular growth and occurrence and timing of follicular rupture in Cynomolgus monkeys.     

Continuous fetal heart rate monitoring during late gestation in cattle by means of Doppler ultrasonography: reference values obtained by computer-assisted analysis

Continuous fetal heart rate (FHR) monitoring using transabdominal Doppler ultrasonography can be assumed to provide information about the viability of the bovine fetus during late gestation, as has been found in humans. To be able to recognize unfavourable fetal conditions, first the normal ranges of FHR parameters in cattle should be established. Therefore, in this study we aimed to determine the normal ranges of computerized FHR parameters, like basal fetal heart rate (BHR), number of accelerations and decelerations per hour and short and long term variation (STV and LTV) during the last 3 weeks before calving (n = 21 cows). Each cow had one recording in each of three episodes of 7 days before parturition. As recording time in the cow is limited, we also studied whether these FHR parameters differ between recordings of 30 and 60 min duration (n = 31 pairs of recordings). The outcomes of FHR recordings with a duration of 30 or 60 min did not differ significantly, except for a higher percentage of signal loss in the 60 min recordings. Therefore, determination of normal ranges was performed in 30 min recordings. BHR decreased from 3 to 2 weeks (114 to 109 bpm; P < 0.0001) before parturition and then remained constant until 2 days before calving. The mean number of accelerations per hour ranged between 4.4 and 5.0 h(-1) and did not change significantly with time. Compared to 3 weeks before parturition, STV was significantly higher at 2 weeks (P < 0.05), but not at 1 week before parturition (8.1, 10.0, and 9.2 ms, respectively). Changes in LTV showed a time course comparable to that of STV, but significance was not reached (51.4, 58.6, and 58.4 ms for respectively 3, 2 and 1 weeks before parturition). No decelerations were found during the period understudy. In conclusion, this study has provided normal ranges of bovine computerized FHR parameters during the last 3 weeks of gestation, allowing a comparison with data from cows with compromised gestations in future.