A visual query-by-example image database for chest CT images: potential role as a decision and educational support tool for radiologists.

Primary reading or further evaluation of diagnostic imaging examination often needs a comparison between the actual findings and the relevant prior images of the same patient or similar radiological data found in other patients. This support is of clinical importance and may have significant effects on physicians' examination reading efficiency, service-quality, and work satisfaction. We developed a visual query-by-example image database for storing and retrieving chest CT images by means of a visual browser Image Management Environment (IME) and tested its retrieval efficiency. The visual browser IME included four fundamental features (segmentation, indexing, quick load and recall, user-friendly interface) in an integrated graphical environment for a user-friendly image database management. The system was tested on a database of 2000 chest CT images, randomly chosen from the digital archives of our institutions. A sample of eight heterogeneous images were used as queries and, for each of them a team of three expert radiologists selected the most similar images from the database (a set of 15 images containing similar abnormalities in the same position of the query). The sensitivity and the positive predictive factor, both averaged over the 8 test queries and 15 answers, were respectively 0.975 and 0.91 The IME system is currently under evaluation at our institutions as an experimental application. We consider it a useful work-in-progress tool for clinical practice facilitating searches for a variety of radiological tasks.

Radiotherapy-related fatigue.

Radiotherapy-induced fatigue is a common early and chronic side-effect of irradiation, reported in up to 80 and 30% of patients during radiation therapy and at follow-up visits, respectively. It is frequently underestimated by medical and nursing staff, only about 50% of patients discuss it with a physician and in one fourth of cases any intervention is proposed to the patient. The patients rarely expect fatigue to be a side-effect of treatment. The etiology of this common symptom, its correlates and prevalence are poorly understood. In numerous studies the level and time course of fatigue was demonstrated to depend on the site of tumor and treatment modalities. For example, psychological mechanisms have been proposed to explain fatigue in women receiving irradiation for early breast cancer, whereas decline in neuromuscular efficiency rather than psychological reasons can lead to the fatigue observed in patients undergoing radiotherapy for prostate cancer. Fatigue can affect global quality of life more than pain, sexual dysfunction and other cancer- or treatment-related symptoms. Several interventions have been tested in the management of radiotherapy-related fatigue and some randomized studies have been recently published. Although an optimal method has not yet been established, some promising results have been reported with relaxation therapy, group psychotherapy, physical exercise and sleep. Further methodologically correct studies are warranted to define better the causes, optimal prevention and management of this symptom.