Oklu, Rahmi

The clinical significance of valves within gonadal veins is controversial. In males, the absence of valves in the left testicular vein (compared to the right) has been cited as a potential mechanism for varicocele formation in the pampiniform plexus in the scrotum. In females, ovarian vein valve absence or incompetence may lead to pelvic congestion syndrome, a disputed explanation for pelvic, abdominal, and/or flank pain of unknown etiology. One study suggests that females have incompetent valves in dilated veins more frequently than males due to past pregnancies. Furthermore, inconsistencies exist in the reported incidence of gonadal vein valves, though pelvic insufficiency is more thoroughly documented and diagnosed in males than in females. This study assesses the presence, number, and location of gonadal vein valves in male and females. The right and left gonadal veins were evaluated in 13 embalmed cadavers (7 males, 6 females; mean age = 86.3 +/− 6.2 years). Twenty‐four veins were available for dissection; two veins were lost to dissection and therefore omitted. The veins were dissected from the ovary (females) or deep inguinal ring (males) to the point of drainage into the inferior vena cava (right gonadal vein) or left renal vein (left gonadal vein). The veins were incised along the entire length of this course, and the number and location of valves was noted and photographed. Anatomical variation and pathological dilation in the vasculature was also documented. A total of 8 valves were found among the 24 dissections. Valves were present in four of the six females (67%) compared to one out of seven males (14%). The valve in the male was located in the left gonadal vein; the bilateral distribution in females was more randomly patterned. The majority of the valves (87.5%) in females were located distally, adjacent to the ovary, while a single valve was located adjacent to the left renal vein confluence. No dilation was noted in any of the specimens. The male population in this study had a lower incidence of gonadal vein valves than in previous studies. However, the number of valves in female gonadal veins was considerably greater than in males. This finding has not been reported previously, perhaps due to the emphasis on male pelvic congestion as a risk for infertility versus attributing the condition in females to a psychosomatic etiology. The primary limitation of this research is the small sample size. Future work will explore the clinical implications of these preliminary findings in a patient population. Clinical correlation with patients who are suspected or known to suffer from pelvic congestion syndrome may shed further light on the role of gonadal vein valves in vein sufficiency and inform more effective treatment for this poorly understood condition in the female patient population.

AbstractContent used by Medical Physicists for fluoroscopy safety training to staff is deliverable via several formats, that is, online content or a live audience slide presentations. Here, we share one example of a kinesthetic (live, hands‐on simulation) educational program in use at our facility for some time (~10 years). In this example, the format and content specifically target methods of reducing physician operator exposures from scattered x rays. A kinesthetic format identifies and promotes the adoption of exposure‐reducing behaviors. Key kinesthetic elements of this type of training include: physician hands‐on measurements of radiation levels at locations specific to their standing positions (e.g., primary arterial access points) in the room using handheld exposure rate meters, measurement of exposure rate reduction to physicians provided by using personal protective equipment, that is, wearable aprons, hanging lead drapes, and pull‐down shields. Physician choice of procedure‐specific tableside selectable controls affecting exposure rate from optional fluoroscopy, Cine or digital subtraction angiography (DSA), along with comparative measured contribution to physician exposure is demonstrated. The inverse square exposure rate reduction to physicians when stepping back from the table during DSA is a key observation. Kinesthetic simulations in the rooms used by physicians have been found to provide the highest level of understanding giving rise to adoption of practices that are impactful for physicians. Specific training scripts are in place for physician sub‐specialization in interventional radiology, cardiology, neurosurgery, vascular surgery, and gastroenterology. This training is used for new physician staff while classroom presentations (whose content mimics in room training) are used with staff who have had previously had in room training.

Abstract Minimally invasive transcatheter embolization is a common nonsurgical procedure in interventional radiology used for the deliberate occlusion of blood vessels for the treatment of diseased or injured vasculature. A wide variety of embolic agents including metallic coils, calibrated microspheres, and liquids are available for clinical practice. Additionally, advances in biomaterials, such as shape‐memory foams, biodegradable polymers, and in situ gelling solutions have led to the development of novel preclinical embolic agents. The aim here is to provide a comprehensive overview of current and emerging technologies in endovascular embolization with respect to devices, materials, mechanisms, and design guidelines. Limitations and challenges in embolic materials are also discussed to promote advancement in the field.

Cancer tissue engineering has remained challenging due to the limitations of the conventional biofabrication techniques to model the complex tumor microenvironment. Here, the utilization of a sacrificial bioprinting strategy is reported to generate the biomimetic mammary duct‐like structure within a hydrogel matrix, which is further populated with breast cancer cells, to model the genesis of ductal carcinoma and its subsequent outward invasion. This bioprinted mammary ductal carcinoma model provides a proof‐of‐concept demonstration of the value of using the sacrificial bioprinting technique for engineering biologically relevant cancer models, which may be possibly extended to other cancer types where duct‐like structures are involved.

Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer and affects millions worldwide. Due to the lack of effective systemic therapies for HCC, researchers have been investigating the use of locoregional tumor control with Yttrium-90 (Y90) radioembolization since the 1960s. Following the development of glass and resin Y90 microspheres in the early 1990s, Y90 radioembolization has been shown to be a safe and efficacious treatment for patients with HCC across Barcelona Clinic Liver Cancer (BCLC) stages. By demonstrating durable local control, good long term outcomes, and equivalent if not superior tumor responses and tolerability when compared to alternative therapies including transarterial chemoembolization (TACE) and sorafenib, Y90 radioembolization is being increasingly used in HCC treatment. More recently, investigations into variations in Y90 radioembolization technique including radiation segmentectomy and radiation lobectomy have further expanded its clinical utility. Here, we discuss the history and evolution of Y90 use in HCC. We outline key clinical trials that have established the safety and efficacy of Y90 radioembolization, and also summarize trials comparing its efficacy to existing HCC treatments. We conclude by reviewing the techniques of radiation segmentectomy and lobectomy, and by discussing dosimetry.

Radiogenomics is a computational discipline that identifies correlations between cross-sectional imaging features and tissue-based molecular data. These imaging phenotypic correlations can then potentially be used to longitudinally and non-invasively predict a tumor’s molecular profile. A different, but related field termed radiomics examines the extraction of quantitative data from imaging data and the subsequent combination of these data with clinical information in an attempt to provide prognostic information and guide clinical decision making. Together, these fields represent the evolution of biomedical imaging from a descriptive, qualitative specialty to a predictive, quantitative discipline. It is anticipated that radiomics and radiogenomics will not only identify pathologic processes, but also unveil their underlying pathophysiological mechanisms through clinical imaging alone. Here, we review recent studies on radiogenomics and radiomics in liver cancers, including hepatocellular carcinoma, intrahepatic cholangiocarcinoma, and metastases to the liver.