RESUMEN
RATIONALE AND OBJECTIVES: The primary objective of this study was to compare computed tomography (CT) volumetric analysis of pleural effusions with thoracentesis volumes. The secondary objective of this study was to compare subjective grading of pleural effusion size with thoracentesis volumes. MATERIALS AND METHODS: This was a retrospective study of 67 patients with free-flowing pleural effusions who underwent therapeutic thoracentesis. CT volumetric analysis was performed on all patients; the CT volumes were compared with the thoracentesis volumes. In addition, the subjective grading of pleural effusion size was compared with the thoracentesis volumes. RESULTS: The average difference between CT volume and thoracentesis volume was 9.4 mL (1.3%) ± 290 mL (30%); these volumes were not statistically different (P = .79, paired two-tailed Student's t-test). The thoracentesis volume of a "small," "moderate," and "large" pleural effusion, as graded on chest CT, was found to be approximately 410 ± 260 cc, 770 ± 270 mL and 1370 ± 650 mL, respectively; the thoracentesis volume of a "small," "moderate," and "large" pleural effusion, as graded on chest radiograph, was found to be approximately 610 ± 320 mL, 1040 ± 460 mL, and 1530 ± 830 mL, respectively. CONCLUSIONS: CT volumetric analysis is an accessible tool that can be used to accurately quantify the size of pleural effusions.
Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Derrame Pleural/diagnóstico por imagen , Toracocentesis/métodos , Estudios de Cohortes , Drenaje/métodos , Humanos , Radiografía Torácica/métodos , Estudios Retrospectivos , Ultrasonografía Intervencional/métodosRESUMEN
Providing an adequate method of distance learning is a challenge faced by many multicenter residency programs. The delivery of live didactics over the Internet is a convenient means of providing a uniform and equivalent educational experience to residents at distant sites. An application called MedCast has been developed with use of existing technologies, without the need for costly commercial products or equipment. MedCast captures the presenter's computer screen and audio from a microphone source to produce a streaming video that is transmitted online and archived on a local server. Offsite residents can view broadcasts in real time or access archived conference sessions for later viewing. MedCast is available for download at no cost and offers several advantages, including a user-friendly graphical display interface, near-perfect preservation of image quality, and cost efficiency. Future plans include objective assessment of the efficacy of MedCast by comparing postlecture examinations to help evaluate for any differences between on- and offsite residents in terms of knowledge gained. A movie clip to supplement this article is available online at http://radiographics.rsnajnls.org/cgi/content/full/285085701/DC1.
Asunto(s)
Instrucción por Computador/métodos , Educación a Distancia/métodos , Educación a Distancia/organización & administración , Internet , Internado y Residencia/organización & administración , Radiología/educación , Programas Informáticos , Estados Unidos , Interfaz Usuario-ComputadorRESUMEN
Teleradiology allows contemporaneous interpretation of imaging exams performed at some distance from the interpreting radiologist. The transmitted images are usually static. However, there is benefit to real-time review of full-motion ultrasound (US) exams as they are performed. Telesonography is transmission of full-motion sonographic data to a remote site. We hypothesize that US exams, read after having been compressed utilizing Motion Picture Experts Group version 4 (MPEG-4) compression scheme, transmitted over the Internet as streaming multimedia, decompressed, and displayed, are equivalent in diagnostic accuracy to reading the examinations locally. MPEG-4 uses variable compression on each image frame to achieve a constant output bit rate. With less compression, the bit rate rises, and the only way the encoder can contain bit rate within the set bandwidth is by lowering frame rate or reducing image quality. We review the relevant technologies and industry standard components that will enable low-cost telesonography.