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[en] Complexities of fetal and placental development introduce unique problems in quantitating a fetal radiation dose from internal radionuclide contamination. The paper briefly describes the many transitory stages in the development of the fetal organs and placenta from the time of the union of the egg and sperm. Descriptions of migration, differentiation and functional changes of cell lines will illustrate the difficulties in establishing a radiation history. The development of the cells responsible for hematopoiesis are reviewed, along with the thyroid gland and blood brain barrier, because of the importance of these tissues in radiation protection. (author)
[en] Diagnostic ultrasound has become one of the most useful tools in the practice of obstetrics. It has been of particular utility in the placental localization. We analyzed 34 patients of placenta previa scanned by ultrasound. The results were as follows; 1. The age of patient ranged from 22 to 39 years, showing the highest incidence in 26 to 30 years. 2. The accuracy of correct localization was 70.6%. 3. Among 13 cases diagnosed by ultrasound as total placenta previa, 2 cases were partial placental previa and 1 was low-lying placenta at the time of delivery. 4. Among 9 cases diagnosed by ultrasound as partial placenta previa, 1 case was total placenta previa and 1 case was low-lying placenta and 1 case was upper segment placenta. 5. Among 10 cases diagnosed by ultrasound as low-lying placenta, 2 cases were partial placenta previa. 6. Among 2 cases diagnosed by ultrasound as upper segment placenta, 1 case was total placenta previa and 1 case was partial placenta previa. 7. Among 9 cases done serial ultrasound, 3 cases revealed that the placenta migrates toward fundus in the course of pregnancy. Therefore, the placental scanning should be repeated in the last month before term to decide the mode of delivery. Conclusively, ultrasonography is the imaging modality of choice in the evaluation of placenta localization because it provides speedy and repeatable way without any known risk to both mother and fetus itself. Careful performance and accurate interpretation should be needed for more correct placental localization.
[en] The retrospective analysis of the clinical and radiological features of 20 patients diagnosed as having malignant pleural mesothelioma (MPM). The radiological studies were based on images from plain chest X-ray (n=20) and computed tomography (CT) (n=19) or magnetic resonance (n=1). The most common radiological signs were dyspnea, chest pain and constitutional symptoms. Fifteen percent of the patients presented a history of exposure to asbestos. The most significant radiological findings were pleural effusion (n=19), pericardial thickening (n=7) and mediastinal lymph nodes (n=5). Calcified mass lesions and pleural plaques and involvement of chest wall and diaphragm were also observed in some lesions. The incidence was similar in both and left hemithorax. Ct is the imaging technique of choice in the assessment and staging of MPM, being more effective than plain X-ray in detecting calcified pleural masses and in assessing chest wall and pericardial involvement. Biopsy obtained by thoracotomy or thoracoscopy and CT-guided transthoracic needle biopsy are the techniques with the greatest diagnostic yield. (Author) 27 refs
[en] Human placenta functions as an important transport organ that mediates the exchange of nutrients and metabolites between maternal and fetal circulations. This function is made possible because of the expression of a multitude of transport proteins in the placental syncytiotrophoblast with differential localization in the maternal-facing brush border membrane versus the fetal-facing basal membrane. Even though the physiological role of most of these transport proteins is to handle nutrients, many of them interact with xenobiotics and pharmacological agents. These transport proteins therefore play a critical role in the disposition of drugs across the maternal-fetal interface, with some transporters facilitating the entry of drugs from maternal circulation into fetal circulation whereas others preventing such entry by actively eliminating drugs from the placenta back into maternal circulation. The net result as to whether the placenta enhances the exposure of the developing fetus to drugs and xenobiotics or functions as a barrier to protect the fetus from such agents depends on the types of transporters expressed in the brush border membrane and basal membrane of the syncytiotrophoblast and on the functional mode of these transporters (influx versus efflux)
[en] There are a variety of fat-containing lesions that can arise in the intraperitoneal cavity and retroperitoneal space. Some of these fat-containing lesions, such as liposarcoma and retroperitoneal teratoma, have to be resected, although resection can be deferred for others, such as adrenal adenoma, myelolipoma, angiomyolipoma, ovarian teratoma, and lipoma, until the lesions become large or symptomatic. The third group tumors (i.e., mesenteric panniculitis and pseudolipoma of Glisson's capsule) require medical treatment or no treatment at all. Identifying factors such as whether the fat is macroscopic or microscopic within the lesion, the origin of the lesions, and the presence of combined calcification is important for narrowing the differential diagnosis. The development and widespread use of modern imaging modalities make identification of these factors easier so narrowing the differential diagnosis is possible. At the same time, lesions that do not require immediate treatment are being incidentally found at an increasing rate with these same imaging techniques. Thus, the questions about the treatment methods have become increasingly important. Classifying lesions in terms of the necessity of performing surgical treatment can provide important information to clinicians, and this is the one of a radiologist's key responsibilities
[en] Twin-to-twin transfusion syndrome (TTTS) is a severe complication in monochorionic twin pregnancies that results from a hemodynamical imbalance of placentar vascular anstomoses that connect the circulation of both fetuses. In TTTS, a poly/oligohydramnios sequence with high fetal morbidity and mortality rates occurs. Fetoscopic laser coagulation of the placentar anastomoses can limit or prevent fetal injury. The purpose of this report is to present and discuss fetal magnetic resonance imaging as a postoperative imaging tool after fetoscopic laser coagulation
[en] Solitary fibrous tumours of the pleura (SFTP) are rare tumours. They are mostly benign. Only around 12% of them are malign ant. In the initial stage they are mostly asymptomatic and by growing they cause chest pain, irritating cough and dyspnoea on account of the pressure created on the surrounding structures. Rare giant tumours have compression symptoms on the mediastinal structures. The condition requires tiered diagnostic radiology. Preoperative biopsy is not successful in most cases. The therapy of choice is radical surgical tumour removal. Malignant or non-radically removed benign solitary fibrous tumours of the pleura additionally require neoadjuvant therapy. A 68-year old patient was hospitalized for giant solitary fibrous tumour of the pleura in the right pleural cavity. With its expansive growth the tumour caused the shift of the mediastinum by compressing the lower vena cava, right cardiac auricle as well as the intermediate and lower lobe bronchus. Due to cardiac inflow obstruction and right lung collapse, the patient’s life was endangered with signs of cardio-respiratory failure. After preoperative diagnostic radiology, the tumour was surgically removed. Postoperatively, the patient’s condition improved. No disease recurrence was diagnosed after a year. Giant solitary fibrous tumour of the pleura may cause serious and life-threatening conditions by causing compression of the pleural cavity with its expansive growth. Early diagnosis of the condition enables less aggressive as well as video-assisted thoracic surgery in patients with significantly better state of health. Large tumour surgeries in cardio-respiratory affected patients are highly risk-associated procedures
PurposeTo investigate the diagnostic accuracy of MRI for placenta accreta spectrum (PAS) and clinical outcome prediction in women with placenta previa, using a novel MRI-based predictive model.
MethodsThirty-eight placental MRI exams performed on a 1.5T scanner were retrospectively reviewed by two radiologists in consensus. The presence of T2 dark bands, myometrial thinning, abnormal vascularity, uterine bulging, placental heterogeneity, placental protrusion sign, placental recess, and percretism signs was scored using a 5-point scale. Pathology and clinical intrapartum findings were the standard of reference for PAS, while intrapartum/peripartum bleeding and emergency hysterectomy defined the clinical outcome. Receiver-operating characteristic (ROC) analysis and discriminant function analysis were performed to test the predictive power of MRI findings for both PAS and clinical outcome prediction.
ResultsAbnormal vascularity and percretism signs were the two most predictive MRI features of PAS. The area under the curve (AUC) of the predictive function was 0.833 (cutoff 0.39, 67% sensitivity, 100% specificity, p = 0.001). Percretism signs and myometrial thinning were the two most predictive MRI features of poor outcome. AUC of the predictive function was 0.971 (cutoff − 0.55, 100% sensitivity, 77% specificity, p < 0.001).
ConclusionThe diagnostic accuracy of MRI, especially considering the combination of the most predictive MRI findings, is higher when the target of the prediction is the clinical outcome rather than the PAS.