Aims: The comparison of elastographic features of quadriceps and patellar tendons in a group of professional athletes and healthy volunteers and the description of elasticity characteristics of these tendons. Material and methods: Thirtynine professional athletes (22 male, 17 female; mean age 18.5 years) and 35 healthy volunteers (21 male, 14 female; mean age 19 years) were included. They were divided into two groups by gender. Quadriceps tendon, patellar side of the patellar tendon, and tibial side of the patellar tendon elasticity patterns and strain ratios were investigated with real-time ultrasound elastography. The elasticity features of the dominant leg and non-dominant leg of athletes and volunteers legs were compared. In addition quadriceps and patellar tendons were compared separately for three distinct tendon locations. Results: There was no difference between the athletes and the healthy volunteers and also between the dominant leg and non-dominant leg of athletes. At tendon comparison, the quadriceps tendon was harder than the patellar tendon at both side and patellar side of patellar tendon was found to be stiffer than the tibial side of patellar tendon. Conclusions: Although biomechanical studies showed that tendon stiffness increased after long exercise, no significant difference was found between athletes' and healthy volunteers' tendon elasticity. These three tendon locations exhibit different elasticity features and the knowledge of the elasticity feature will be useful in assessing tendon pathologies.

Preoperative ADC values could differentiate the main histological subtypes of pediatric posterior fossa tumors with high sensitivity and specificity.

QSM is more reliable than SWI phase images in the identification of intracranial calcification and hemorrhage in pediatric patients using MR imaging.

Our study stands out as the most comprehensive study with larger sample size on this topic. Moreover, we are able to suggest a cut-off value which can discriminate neuroblastoma from ganglioneuroblastoma and ganglioneuroma. We believe that ADC will evolve to an objective, quantitative measurement in discrimination among malignant and benign neuroblastic tumors.

ABDOMINAL IMAGINGORIGINAL ARTICLE PURPOSE We aimed to assess the feasibility and reproducibility of real-time elastography (RTE) for displaying the effects of morphological changes in the ovary in polycystic ovary syndrome (PCOS). METHODSForty-eight patients diagnosed with PCOS and 48 healthy women were enrolled in the study. Ultrasonography and RTE were performed on the 3 rd day of the menstrual cycle. Evaluations were performed independently by two radiologists. Ovarian volume, number of follicles, elasticity pattern, and strain ratio were measured. Elasticity patterns were assessed as hard (type 1; blue or blue-green), moderate (type 2; green or green-yellow) or soft (type 3; red or orange-red). RESULTSBoth radiologists determined the elasticity pattern as mostly type 1 in the PCOS group and type 3 in the control group (P < 0.01). The mean strain ratios obtained by the first and second radiologist were 6.1±1.8 (2.7-10.1) and 6.0±1.5 (3.0-9.0) in PCOS and 3.3±1.2 (1.7-7.2) and 3.2±0.9 (1.7-6.8) in the control group, respectively (P < 0.001). Interobserver agreement was moderate for the elasticity pattern (κ=0.48) and good for the strain ratio (intraclass correlation coefficient, 0.77). A strain ratio of 3.8 was determined as the optimized cutoff point by receiver operating curve analysis. Strain ratio was correlated with the ovarian volume and the number of detected follicles (P < 0.001). CONCLUSION Elasticity pattern and strain ratio can help identify morphological changes that make PCOS ovaries stiffer than normal ovaries. In reproductive-aged women, polycystic ovary syndrome (PCOS) is an important cause of infertility and is characterized by menstrual irregularities, hirsutism and signs of hyperandrogenism, and polycystic ovary appearance (1-3). In addition to insulin resistance, serum androgenic hormone levels are increased, causing undesired effects on women's metabolic, reproductive, and cardiovascular health (1-5). PCOS is characterized by enlarged ovaries containing small cysts, for which the syndrome was named (6).Real-time elastography (RTE) is a novel and dynamic imaging technique that is simply based on the hardness or softness of tissues or organs under the appropriate compression and can be used with conventional ultrasonography (US) probes after performing gray-scale and Doppler US. Displacement of soft tissues is greater than hard tissues, and tissue hardness is displayed as a color-coded image that lays over the gray-scale US image translucently (7). Elastography has been used previously for differentiation of pathologies of tissues and organs, such as thyroid, breast, kidneys, and liver (7-9). There are limited studies about the elastographic properties of the ovaries, mostly focused on ovarian neoplasms and, to the best of our knowledge, there is no medical data concerning the elasticity properties of the ovary in PCOS (10, 11). In this study, our purpose was to assess the feasibility and reproducibility of RTE for displaying the effects of morphological changes in the ovary in PCOS and to p...