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The high prevalence and burden of uterine fibroids in women raises questions about the origin of these benign growths. Here, we propose that fibroids should be understood in the context of human evolution, specifically the advent of bipedal locomotion in the hominin lineage. Over the ≥7 million years since our arboreal ancestors left their trees, skeletal adaptations ensued, affecting the pelvis, limbs, hands, and feet. By 3.2 million years ago, our ancestors were fully bipedal. A key evolutionary advantage of bipedalism was the freedom to use hands to carry and prepare food and create and use tools which, in turn, led to further evolutionary changes such as brain enlargement (encephalization), including a dramatic increase in the size of the neocortex. Pelvic realignment resulted in narrowing and transformation of the birth canal from a simple cylinder to a convoluted structure with misaligned pelvic inlet, mid-pelvis, and pelvic outlet planes. Neonatal head circumference has increased, greatly complicating parturition in early and modern humans, up to and including our own species. To overcome the so-called obstetric dilemma provoked by bipedal locomotion and encephalization, various compensatory adaptations have occurred affecting human neonatal development. These include adaptations limiting neonatal size, namely altricial birth (delivery of infants at an early neurodevelopmental stage, relative to other primates) and mid-gestation skeletal growth deceleration. Another key adaptation was hyperplasia of the myometrium, specifically the neomyometrium (the outer two-thirds of the myometrium, corresponding to 90% of the uterine musculature), allowing the uterus to more forcefully push the baby through the pelvis during a lengthy parturition. We propose that this hyperplasia of smooth muscle tissue set the stage for highly prevalent uterine fibroids. These fibroids are therefore a consequence of the obstetric dilemma and, ultimately, of the evolution of bipedalism in our hominin ancestors., (© The Author(s) 2024. Published by Oxford University Press on behalf of European Society of Human Reproduction and Embryology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Objective: During mature placenta formation, select fetal trophoblasts invade maternal decidual arterioles and junctional zone arteries and change them into low-resistance uteroplacental arteries. Consequently, physicians performing vascular procedures that occlude the uterine arteries should understand their effects on miscarriage rates, the various toxemias of pregnancy, gross and microscopic placental anatomy, and invasive placentation. Thus, the objective of this article is to review the effects of vascular occlusion on pregnancy., Conclusion: In the long run, placental abnormalities may be the canary in the mine shaft to globally judge the effect of uterine artery embolization on pregnancy.

Objective: This commentary deals with the study by Verma et al. discussing submucosal and endocavitary fibroids after uterine artery embolization (UAE)., Conclusion: UAE can infarct fibroids. Fibroids spontaneously infarct after childbirth. Because the postpartum cervix is patulous, infarcted fibroids that fall into the uterine cavity easily exit the uterus. Each patient contemplating UAE should anticipate that infarcted fibroids bordering on or inside the uterine cavity may require cervical dilatation or hysteroscopic resection for removal. The addition of either of these two gynecology procedures should not necessarily be regarded as a UAE complication or treatment failure.

Symptomatic uterine fibroids are a relatively common gynecologic condition. In the past, fibroids were exclusively treated by myomectomy and/or hysterectomy. With the advent of uterine artery embolization or uterine artery occlusion, there now exist minimally invasive approaches to fibroid therapy especially for women in whom surgery is contraindicated or for those who wish to retain their uterus and possibly fertility. Fertility and pregnancy outcomes after these minimally invasive therapies are currently being evaluated.

When the uterine arteries are bilaterally occluded, either by uterine artery embolization or by laparoscopic obstruction, women with myomas experience symptomatic relief. After the uterine arteries are occluded, most blood stops flowing in myometrial arteries and veins, and the uterus becomes ischemic. It is postulated that myomas are killed by the same process that kills trophoblasts: transient uterine ischemia. When the uterine arteries are bilaterally occluded, either by uterine artery embolization (UAE) or by laparoscopic obstruction, women with myomas experience symptomatic relief. After the uterine arteries are occluded, most blood stops flowing in myometrial arteries and veins, and the uterus becomes ischemic. Over time, stagnant blood in these arteries and veins clots. Then, tiny collateral arteries in the broad ligament (including communicating arteries from the ovarian arteries) open, causing clot within myometrium to lyse and the uterus to reperfuse. Myomas, however, do not survive this period of ischemia. This is unique organ response to clot formation and ischemia. What allows the uterus to survive a relatively long period of ischemia while myomas perish? Childbirth appears to be the predicate biology. Following placental separation, the uteroplacental arteries and the draining veins of the placenta are torn apart at their bases in the junctional zone of the myometrium and bleed directly into the uterine cavity. Left unchecked, every woman would bleed to death in less than 10 minutes after placental delivery. Most women do not bleed to death because vessels in the uterus clot after placental delivery. During pregnancy, clotting and lytic factors in blood increase many fold. Following delivery, uterine contractions continue, intermittently, periodically slowing the velocity of flowing blood through myometrium. The combination of slowed blood flow, elevated clotting proteins, and torn placental vessels (known as Virchow's triad) causes blood in myometrial arteries and veins to clot. Fibrinolytic enzymes later lyse clot in arteries and veins not associated with placenta perfusion, and the uterus is reperfused. Remnant placental tissue - primarily uteroplacental arteries and veins - does not survive this period of ischemia. Placental tissue dies and over weeks is sloughed into the uterine cavity. At the same time, residual endometrial tissue grows under the sloughing placental tissue thus re-establishing the endometrial lining. It is postulated that myomas are killed by the same process that kills trophoblasts - transient uterine ischemia.

Purpose: To measure the effect of biopsy device, probe size, mammographic lesion type, lesion size, and number of samples obtained per lesion on the ductal carcinoma in situ (DCIS) underestimation rate., Materials and Methods: Nonpalpable breast lesions at 16 institutions received a histologic diagnosis of DCIS after 14-gauge automated large-core biopsy in 373 lesions and after 14- or 11-gauge directional vacuum-assisted biopsy in 953 lesions. The presence of histopathologic invasive carcinoma was noted at subsequent surgical biopsy., Results: By performing the chi(2) test, independent significant DCIS underestimation rates by biopsy device were 20.4% (76 of 373) of lesions diagnosed at large-core biopsy and 11.2% (107 of 953) of lesions diagnosed at vacuum-assisted biopsy (P <.001); by lesion type, 24.3% (35 of 144) of masses and 12.5% (148 of 1,182) of microcalcifications (P <.001); and by number of specimens per lesion, 17.5% (88 of 502) with 10 or fewer specimens and 11.5% (92 of 799) with greater than 10 (P <.02). DCIS underestimations increased with lesion size., Conclusion: DCIS underestimations were 1.9 times more frequent with masses than with calcifications, 1.8 times more frequent with large-core biopsy than with vacuum-assisted biopsy, and 1.5 times more frequent with 10 or fewer specimens per lesion than with more than 10 specimens per lesion.

The purpose of this study was to compare specimen weights, tissue acquisition times, and complication rates for 14- and 11-gauge Mammotome probes during stereotactic breast biopsy. Three hundred forty stereotactic Mammotome breast biopsies were reviewed for complications; 269 (79%) of these biopsies were performed with the 14-gauge Mammotome probe, and 71 (21%) with the 11-gauge probe. Aggregate specimen weights and tissue acquisition times were measured in 248 out of 340 stereotactic Mammotome breast biopsies. Of these 248 lesions, 186 (75%) were performed with the 14-gauge probe, and 62 (25%) with the 11-gauge probe. Complication rates were essentially the same for each probe: 1.1 per cent for the 14-gauge probe and 1.4 per cent for the 11-gauge probe (not significant). More total aggregate breast tissue was obtained during the biopsies performed with the 11-gauge Mammotome probes than with the 14-gauge probes (1730 versus 1067 mg; P < or = 0.0001). The number of specimens acquired was smaller during the 11-gauge biopsy sessions (18 versus 27; P < or = 0.0001). The average per-specimen weight was significantly higher with the 11-gauge probe: 96 versus 40 mg per specimen (P < or = 0.0001). The average tissue harvesting time was approximately the same with each probe size, 15.6 minutes for the 11-gauge probe and 15.4 for the 14-gauge probe (not significant). Consequently, the harvesting rate (mg of tissue obtained per minute) was 111 mg/minute with the 11-gauge probe versus 69 with the 14-gauge probe (P < or = 0.0001). The per-specimen breast tissue yield, using the 11-gauge probe, was more than two times greater than the yield using the 14-gauge probe. There was no increase in procedure time, and there were no additional complications.

The current study was performed to determine whether the Mammotome, a new breast biopsy instrument, is better at harvesting breast tissue percutaneously than an automated Tru-Cut (ATC) device. A total of 345 stereotactic breast biopsies were performed with the Mammotome. The Mammotome specimens were clinically evaluated on a five-point specimen scale that reflected the quality and quantity of the specimens and the rapidity of collection. In selected cases, specimen weights from both techniques were measured. In addition, by examining the lesion site post-biopsy, biopsies were categorized as incisional or excisional. Specimens obtained with the Mammotome were two times heavier than when obtained with the Biopty gun (34.3 mg vs. 17.2 mg, P < or = 0.0002). When aggregate Mammotome specimen weights were regressed against number of specimens submitted, average weight per specimen was 31.9 mg (P < or = 0.0001). When compared with the ATC device on the specimen scale, the Mammotome specimens were rated "Average" in 2.1 percent, "Good" in 13 percent, and "Very Good" in 84.9 percent. Also, 51.9 percent of the biopsies with the Mammotome were judged to be incisional; 48.1 percent, excisional. Three minor complications were encountered. The Mammotome more quickly harvests more breast tissue compared with ATC technology.

In 1988 two separate technologies were joined together by a team of radiologists in Denver, Colorado: a stereotactic breast biopsy system and an automated biopsy gun system. With the union of these two technologies, a new era in early breast cancer diagnosis began, stereotactic core breast biopsy. Any lesion that can be seen by mammography can be accurately biopsied with the stereotactic core breast biopsy. The accuracy of the procedure depends upon highly developed mammography skills and is, consequently, an advanced radiology procedure. Accuracy is equal to or greater than accuracy with traditional localization and open, surgical breast biopsy.

Mask mode intravenous digital subtraction angiography (IV-DSA) image quality is directly dependent on the arterial time-concentration curve peak and width produced by contrast media. Curves with high peak iodine concentration produce excellent difference images. Curves that are narrow appear and disappear quickly and minimize movement artifacts. Using a noninvasive x-ray technique for quantitative measurement of contrast media time-concentration curve parameters and cardiac output, three experimental data bases were analyzed. From the analyses, equations defining curve peak and width were derived and validated. Width is proportional to central blood volume and inversely proportional to cardiac output. Peak is proportional to the quantity of contrast media injected and inversely proportional to central blood volume. Hypertonic contrast media increases central blood volume and lowers curve peak. Optimal contrast media for IV-DSA is low in concentration and high in volume. In addition, low concentration contrast media may be more comfortable for the patient causing fewer motion artifacts.

Prior to the formation of an intravenous digital subtraction angiography (IV-DSA) image, contrast medium passes through the lesser circulation and is diluted by the blood volume of the heart and lungs. If the contrast medium alone influences central blood volume or cardiac output, the shape of the resultant time-concentration curve may be degraded. To the extent that contrast medium tonicity reduces curve peak or increases width, image quality for mask mode IV-DSA will suffer. To quantify the effect of contrast medium tonicity upon curve shape, contrast medium (1) at increasing iodine concentration and increasing osmolality and (2) at constant iodine concentration and increasing osmolality was injected into the right atria of mongrel dogs. In both experiments, increasing osmolality was associated with an increase in central blood volume (CBV) and cardiac output. With an increase in CBV, curve peak fell. With an increase in both CBV and cardiac output, curve width was not influenced by increasing osmolality. The effect of osmolality upon CBV was highly variable; in these experiments CBV was influenced more by subject-to-subject variability. However, on the average, higher tonicity contrast media produced curves with lower peaks. These studies suggest that isotonic contrast medium does not increase CBV and that isotonic contrast medium is preferable to hypertonic contrast medium for IV-DSA image formation.

This study compares digital radiographic images of the bile ducts in dogs with images obtained using routine radiography. The dogs were infused with iodipamide (2 ml/minute for 30 minutes), and the bile ducts were imaged at 60 minutes using plain radiograph and five digital techniques: (1) dual-energy, (2) DSA-hybrid prepixel shift, (3) DSA-hybrid postpixel shift, (4) a dual-energy film system--Digirad, and (5) scan projection radiography using hybrid subtraction. Six radiologists who were not familiar with digital radiography evaluated the six different studies. The images were presented in a randomized order and each image was evaluated on a five-point scale. There was no difference between the plain radiographs and the dual-energy images. Both of these studies were rated significantly better (P less than .001) than the other four digital images. These results suggest that digital radiography during direct cholangiography may be easily accomplished using a 10% to 15% iodine solution.

Cardiac magnetic resonance (MR) imaging has developed rapidly to rival echocardiography as a noninvasive imaging modality. Anatomic detail may exceed that currently available using echocardiography techniques, and the ability to image moving protons may compete with Doppler color flow mapping in detecting valvular diseases and shunts. Because of the considerable clinical experience with echocardiography, as angled MR imaging planes become available as standard software packages, it may be useful for MR cardiac imaging to use standard, accepted echocardiographic nomenclature and imaging planes. This article describes the principles used to obtain long and short axis MR images that are comparable with echocardiographic imaging planes. Diagrams and illustrations are provided to orient the viewer using nomenclature common to echocardiography. These views may eventually be useful for functional analysis of the left ventricle and for detection and evaluation of valvular heart disease and intracardiac shunts.

The image quality of temporal (mask mode) intravenous digital subtraction angiography is directly dependent on the shape of arterial time-concentration curves produced by the intravenous injection of contrast medium. Curves that are narrow and tall minimize motion artifact (misregistration) and maximize contrast enhancement (pre- and postcontrast differences). To determine the effects of rate and volume of injection of contrast medium on intravenous digital subtraction angiographic curves, ioxaglate (Hexabrix), a monoacidic ionic dimer, was injected into large mongrel dogs. Quantitative measurements of opacification were made over time in the femoral arteries using a modified General Electric CT/T scanner. Peak opacification was directly proportional to the volume of contrast medium injected. Curve width was not affected by increasing volume of injection. At rates below a critical point, slower injection rates produced progressively shorter and wider arterial time-concentration curves. Above that critical point, increasing the rate of injection did not affect either curve width or curve peak.