MR imaging of bladder endometriosis and its relationship with the anterior uterine wall: experience in a tertiary referral centre.

OBJECTIVE: Both the intraperitoneal seeding and the uterine-vesical extension theory have been proposed to explain the pathogenesis of bladder endometriosis. The aim of this study was to describe MR imaging findings of bladder endometriosis and involvement of the anterior uterine wall in a tertiary referral centre for endometriosis in a effort to improve diagnosis and help clarify the pathogenesis. METHODS: In a single-centre, retrospective study (2004-2009), 463 consecutive patients analysed for deep infiltrating endometriosis (DIE) were studied independently by two experienced readers for the presence of bladder endometriosis. MR studies revealing bladder endometriosis were then analysed in consensus for: location, size, signal intensity characteristics, uterine involvement, continuity with adenomyosis and presence of cysts. There was histopathologic correlation in 9 patients who had undergone partial bladder resection. RESULTS: Bladder endometriosis was diagnosed in 32 patients on MR imaging (k=0.85). Most lesions showed heterogeneous isointensity compared to that of muscle on T2-weighed imaging, containing foci of high signal intensity, suggesting cystic ectopic endometrial glands. On T1-weighted imaging lesions showed heterogeneous isointensity with foci or small cysts, demonstrating high signal intensity, indicating hemorrhage, was observed. Uterine involvement was found in 94% of the lesions, with either "continuous" or "hourglass" configurations. Presence of contiguous adenomyosis was found in only 4 lesions. CONCLUSIONS: With MR imaging, uterine involvement in bladder endometriosis is frequently found and in most cases located subserosally, suggesting extensive DIE, favouring the intraperitoneal seeding theory.

Ontogeny of fetal movements in the guinea pig.

Assessment of fetal motility is an approach to evaluate the development and function of the nervous system before birth. Reference values for the time of first occurrence and the incidence of normal fetal movements are indispensable for studies in which prenatal motor activity is applied as a model to study the central and peripheral nervous systems. Studies on fetal motility have been performed in a few species, particularly in the human. The aim of the present study is to describe the ontogeny of fetal motility in the guinea pig, a precocious polytocous species. After a pilot study to establish procedures for repeated ultasonographic scanning of guinea pigs, 10 domesticated animals were scanned (5.0 or 7.5 MHz convex transducer) at 2-4 day intervals between day 24 and 63 of gestation (term age 68 days). Per animal two selected fetuses were each scanned for 15 min. Images were stored on videotape and analyzed off-line for the first onset, presence and quality of fetal movement patterns, and quantity of sideway bendings, general movements, breathing movements and periods of fetal rest. Twenty-five different movement patterns could be characterized, 6 emerging at the onset of motor activity were performed only temporarily. The very first fetal movement was observed on day 24 gestational age, and subsequently most other movements developed during a period of only 5 days. Interfetal difference in onset of the frequently occurring sideway bendings, general movements, and front and hind limb movements was only 2 days. Sideway bendings and general movements co-existed during days 29 to 43. There were developmental trends in the course of pregnancy. Sideway bendings increased rapidly between 24 and 30 days and declined hereafter. General movements and fetal breathing increased during midpregnancy and declined towards parturition. Conversely, fetal rest was observed for approximately 60% of time at midgestation and a marked increase was found towards parturition. There were no significant differences in developmental trend of the various movement patterns between individual fetuses. Fetal motility in the guinea pig followed a specific temporal pattern, like in the human, but at a different time scale. The present quantitative data will enable functional investigations into the role of the neuromuscular system. They may also facilitate studies on the effect of environmental influences, such as stress, drugs, toxic substances, and food conditions, on fetal neurobehavioural development in this species.