Maximising coverage of brain structures using controlled reflux, convection-enhanced delivery and the recessed step catheter.

Background: The design and use of convection-enhanced delivery catheters remains an active field as clinical trials have highlighted suboptimal distribution as a contributory factor to the failure of those studies. Recent studies indicate limitations and challenges in achieving target coverage using conventional point source delivery.

New Method: The recessed step catheter(RSC), developed by this group, does not function as a point source delivery device, but instead uses 'controlled reflux' of the infusate to a flow inhibiting recess feature.

An Investigation into the Consistency in Mammographic Density Identification by Radiologists: Effect of Radiologist Expertise and Mammographic Appearance.

The aim of this work is to investigate how radiologist expertise and image appearance may have an impact on inter-reader variability of mammographic density (MD) identification. Seventeen radiologists, divided into three expertise groups, were asked to manually segment the areas they consider to be MD in 40 clinical images. The variation in identification of MD for each image was quantified by finding the range of segmentation areas.

Mammographic density and cancer detection: does digital imaging challenge our current understanding?

Rationale And Objectives: To investigate the impact of breast density on the performance of radiologists when mammograms are digitally acquired and displayed.

Materials And Methods: A total of 150 craniocaudal digital mammograms including 75 cases with cancer were examined by 14 radiologists divided into two groups: those who read more (six) and less (eight) than 2000 mammograms per year. Cases were classified as low or high mammographic density.

Markers of good performance in mammography depend on number of annual readings.

Purpose: To explore relationships between reader performance and reader characteristics in mammography for specific radiologist groupings on the basis of annual number of readings.

Materials And Methods: The institutional review board approved the study and waived the need for patient consent to use all images. Readers gave informed consent.

The effect of JPEG2000 compression on detection of skull fractures.

Rational And Objectives: To investigate the effect of the Joint Photographic Experts Group (JPEG2000) 30:1 and 60:1 lossy compression on the detection of cranial vault fractures when compared to JPEG2000 lossless compression.

Materials And Methods: Fifty cranial computed tomography (CT) images were processed with three different level of JPEG2000 compression (lossless, 30:1 lossy, and 60:1 lossy) creating three sets of images. These were presented to five musculoskeletal specialists and five neuroradiologists.

Quantitative measures confirm the inverse relationship between lesion spiculation and detection of breast masses.

Objective: To identify specific mammographic appearances that reduce the mammographic detection of breast cancer.

Materials And Methods: This study received institutional board review approval and all readers gave informed consent. A set of 60 mammograms each consisting of craniocaudal and mediolateral oblique projections were presented to 129 mammogram Breastscreen readers.