ADNEXAL FINDINGS in ECTOPIC PREGNANCY and TUBAL RUPTURE and HCG LEVELS

Discussion

There have been major advances in ultrasound equipment in the past 2 decades. The resulting improved resolution raises the question of whether the sonographic findings of ectopic pregnancy described in the early days of transvaginal sonography still apply today. It is possible that improved resolution has resulted in earlier identification of adnexal abnormalities, with a corresponding change in the distribution of imaging findings. Our study addresses this question and provides an updated understanding of the imaging characteristics of ectopic pregnancy and their relationship to fallopian tube rupture.

We found that the percentage of ectopic pregnancies with a yolk sac or cardiac activity was lower than previously reported. Embryonic cardiac activity was found in fewer than 10% of our patients, similar to a recent report  but much lower than in earlier series, in which up to 24% of ectopic pregnancies had cardiac activity.  The ectopic pregnancy in more than half of our patients appeared as a non-specific adnexal mass, which may have represented a blood clot in some cases. Our study confirms the previously published important point that, in a small number of patients, free fluid may be the only sonographic finding of ectopic pregnancy.

In the early 1990s, color Doppler imaging was suggested as a valuable adjunct for the diagnosis of ectopic pregnancy.  However, we found color Doppler imaging to be of little clinical value: there was no significant relationship between the color pattern and type of adnexal mass, and the addition of color Doppler imaging to the examination did not improve the ability to predict tubal rupture.

Among our patients who underwent surgery within 1 day of the study sonogram, 25.2% proved to have tubal rupture. However, the overall rate of tubal rupture is likely to be much lower, since the women who underwent surgery were not representative of our entire group. Although our study methods do not allow us to determine the overall rate of tubal rupture with ectopic pregnancy, our results do permit us to conclude, as had been noted previously, that sonographic findings are not reliable predictors of rupture. No  single adnexal mass appearance or color Doppler characteristic correlates with the presence or absence of tubal rupture. Only the presence of a moderate-to-large amount of free intraperitoneal fluid was significantly associated with a ruptured fallopian tube, but the finding of this amount of free fluid had poor sensitivity, specificity, and positive predictive value for tubal rupture.

The role of hCG in the diagnosis of ectopic pregnancy is widely debated in the literature. Our study, similar to others,  shows that hCG levels vary widely in women with ectopic pregnancy, from less than 10 mIU/mL in one of  our patients to greater than 100,000 mIU/mLin another, and reinforces the fact that there is no lower-level hCG cutoff value with ectopic pregnancy. The average hCG value increased as the grade of the adnexal mass increased, with the highest average hCG level found in those with cardiac activity, which also confirms other reports.  However, the hCG level did not correlate with the presence or absence of tubal rupture, so this serum measurement has little clinical value if an adnexal mass is seen on sonography.

This study had a few limitations. Measurements of nonspecific adnexal masses were somewhat subjective, since the borders of the masses were not always clear. In particular, some of the poorly defined masses may have represented blood clots, which often do not have discrete margins and may be difficult to measure accurately. Another limitation was that some patients had more than 1 sonographic examination performed before the time of diagnosis. We used the transvaginal sonogram obtained closest to the point of treatment, which may have biased this report toward larger and more advanced adnexal findings. Additionally, some of our patients did not have either surgical or pathologic proof of their ectopic pregnancies but were treated medically.

Vector Tissue Doppler Ultrasound Effective In Imaging Muscle, Tendon Motion

Scientists have developed a new approach that utilizes a Doppler ultrasound for quantifying muscle kinematics. The new technology, which has been designed to image muscle and tendon motion during dynamic tasks, can provide a complementary methodological tool for biomechanical studies in a clinical or laboratory setting. Injured and painful joints feature complicated dynamics the understanding of which can help clinicians figure out how to address a variety of conditions. To visualize the processes involved in muscle and tendon dynamic tasks, the patient has to be imaged while using the injured joint. The investigators have developed an innovative vector tissue Doppler imaging (vTDI) technique that can be used to measure musculoskeletal contraction velocity, strain, and strain rate with submillisecond temporal resolution during dynamic activities using ultrasound. The researchers from George Mason University (Fairfax, VA, USA; www.gmu.edu) have devised the new technology that uses existing modalities to provide a comprehensive picture as to how the musculoskeletal parts of the leg function. Little white balls are fixed to specific points all over the patient’s body and a Doppler ultrasound probe is attached to the leg. The patient is then asked to perform a number of tasks while the ultrasound is recording and cameras monitor the balls to determine exactly how the individual is moving. Fusing the two modalities together provides a new ability to optimize the effectiveness of biomechanical studies. Moreover, other techniques, such as electromyography (EMG), can be used in conjunction to gain additional data. The study’s findings were published in an open access article with a video in September 2013 in the journal JoVE. The aim of this early study was to investigate the repeatability and potential applicability of the vTDI technique in measuring musculoskeletal velocities during a drop-landing task,in healthy subjects. The vTDI measurements can be performed concurrently with other biomechanical techniques, such as three-dimensional (3D)motion capture for joint kinematics and kinetics, EMG for timing of muscle activation and force plates for ground reaction force. Integration of these complementary techniques could lead to a better understanding of dynamic muscle function and dysfunction underlying the pathogenesis and pathophysiology of musculoskeletal disorders. Diagnostic ultrasound can enable direct imaging of muscle and tendons in real time, and therefore is an attractive alternative for measuring musculoskeletal dynamics and function during ADL. Ultrasound-based quantitative measures of muscle morphology and architecture, such as muscle thickness, length, width, cross-sectional area (CSA), fiber pennation angle and fascicle length have been widely used. Image-processing methods have recently been employed to assess and quantify these quantitative measures during dynamic tasks. These advances have enabled a new methodological approach to understanding in vivo muscle function. However, these methods have primarily relied on using conventional grayscale (or B-mode) ultrasound imaging, and therefore have not fully exploited the possibilities of ultrasound to measure tissue velocities, strain, and strain rate using Doppler principles, that have been shown to be valuable in evaluating cardiac muscle function. The vTDI technique can make measurements of muscles and tendons during highly dynamic tasks (e.g., drop-landing, gait) at high frame rates. The investigators have implemented this method on a commercially available ultrasound system with a research interface, enabling this study to bemade in a clinical setting. Vector TDI is based on estimating the resultant velocity vector from Doppler velocity measurements taken from two or more independent directions. An ultrasound system with a research interface was used for developing vTDI. The research interface allowed low-level beam forming and pulse sequence control using a software development kit (SDK). A 5–14 MHz linear array transducer, consisting of 128 transducer elements and with a 38-mm field-of-view was used. The research interface was employed to split the array transducer into two transmit and receive apertures and steer the receive beams by 15° with respect to the normal. The transmit beam was focused in the region of interest (e.g., muscle belly). Transmit and receive apertures were set to 32 elements.

Image: Researchers have put together a system that uses existing technologies to give a detailed view of how the musculoskeletal components of the leg function (Photo courtesy of George Mason University).