The purpose of this article is to present the practicing sonographer and sonologist with an overview of the biohazards of ultrasound and guidelines for safe use.

No abstract

The introduction of ultrasound into medical student education is well underway in many locations around the world, but is still in its infancy or has yet to begin in others. Proper incorporation of ultrasound education into medical training requires planning and resources, both capital and human. In this article, we discuss the state of the art of ultrasound in medical education throughout the world, as well as various methodologies utilized to improve student education and to incorporate ultrasound into every facet of training. Experiences from various educational systems and available evidence regarding the impact of ultrasound education are summarized. Representing multiple societies and specialties throughout the world, we discuss established modern as well as novel education structures and different successful approaches.

The high mortality rate due to ovarian cancer is attributed to the lack of an effective early detection method. Due to the non-specificity of symptoms at early stage, most of the ovarian cancer cases are detected at late stages. This makes the access to women with early stage disease problematic and presents a barrier to development and validation of tests for detection of early stage of ovarian cancer in humans. Animal models are used to elucidate disease etiologies and pathogenesis that are difficult to study in humans. Laying hen is the only available animal that develops ovarian cancer spontaneously; however, detail information on ovarian tumor histology is not available. The goal of this study was to determine the histological features of malignant ovarian tumors in laying hens. A total of 155 young and old (1-5 years of age) laying hens (Gallus domesticus) were selected randomly and evaluated gross and microscopically for the presence of ovarian tumors. Histological classification of tumors with their stages and grades were performed with reference to those for humans. Similar to humans, all four types including serous, endometrioid, mucinous and clear cell or mixed carcinomas were observed in hen ovarian tumors. Some early neoplastic as well as putative ovarian lesions were also observed. Similarities in histology, metastasis and stages of hen ovarian cancer to those of humans demonstrate the feasibility of the hen model for additional delineation of the mechanism underlying ovarian carcinogenesis, preclinical testing of new agents for the prevention and therapy of this disease. Keywordsovarian cancer; preclinical model; laying hen; tumor histology Ovarian cancer (OVCA) is a fatal disease of women with the highest mortality rate of all gynecological malignancies. Approximately 70% of women with OVCA die of this disease (1,2). Survival is high in women who present with early stage disease(3,4). The lack of specific symptoms, the relative inaccessibility of the ovaries deep in the pelvis, and the absence of NIH Public Access Author ManuscriptInt J Gynecol Cancer. Author manuscript; available in PMC 2010 May 1. Published in final edited form as:Int J Gynecol Cancer. 2009 May ; 19(4): 531-539. doi:10.1111/IGC.0b013e3181a41613. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript specific marker(s) represent barriers for early detection (5,6). In most cases, OVCA is diagnosed at a late stage(3). Furthermore, our understanding of the early pathogenesis of OVCA has been hindered by the lack of sufficient number of patients with early stage disease (3,4,7). Animal models are used to elucidate disease etiologies and pathogenesis that are difficult to study in humans. Although large domestic mammals including bovine have similar reproductive traits and develop OVCA spontaneously similar to humans, the low incidence rate, multiple pregnancies, longer gestation and lactation period make them an inappropriate model for human OVCA. On the other hand, a number of rodent models, induced or g...

Ultrasound end users are poorly informed regarding safety issues during pregnancy. Further efforts in the realm of education and training are needed to improve end user knowledge about the acoustic output of the machines and safety issues.

Nuchal cord is not associated with adverse perinatal outcome. Thus, labor induction in such cases is probably unnecessary.

rocesses that can produce a biological effect with some degree of heating (ie, about 1°C above the physiologic temperature) act via a thermal mechanism. Investigations with laboratory animals have documented that pulsed ultrasound can produce elevations of temperature and damage in biological tissues in vivo, particularly in the presence of bone (intracranial temperature elevation). Acoustic outputs used to induce these adverse bioeffects are within the diagnostic range, although exposure times are usually considerably longer than in clinical practice. Conditions present in early pregnancy, such as lack of perfusion, may favor bioeffects. Thermally induced teratogenesis has been shown in many animal studies, as well as several controlled human studies; however, human studies have not shown a causal relationship between diagnostic ultrasound exposure during pregnancy and adverse biological effects to the fetus. All human epidemiologic studies, however, were conducted with commercially available devices predating 1992, that is, with acoustic outputs not exceeding a spatial-peak temporal-average intensity of 94 mW/cm 2 . Current limits in the United States allow a spatial-peak temporal-average intensity of 720 mW/cm 2 for fetal applications. The synergistic effect of a raised body temperature (febrile status) and ultrasound insonation has not been examined in depth. Available evidence, experimental or epidemiologic, is insufficient to conclude that there is a causal relationship between obstetric diagnostic ultrasound exposure and obvious adverse thermal effects to the fetus. However, very subtle effects cannot be ruled out and indicate a need for further research, although research in humans may be extremely difficult to realize.

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