Junji Shiraishi, Presenter: License agreement, Riverain Medical License agreement, MEDIAN Technologies Research support, Riverain Medical Research support, Totoku Electric Co, Ltd Consultant, Riverain Medical

Hiroyuki Abe MD, Abstract Co-Author: Research grant, Totoku Electric Co, Ltd

Katsuhiro Ichikawa PhD, Abstract Co-Author: License agreement, Totoku Electric Co, Ltd Research support, Totoku Electric Co, Ltd

Mikio Hasegawa, Abstract Co-Author: Nothing to Disclose

Kunio Doi PhD, Abstract Co-Author: Shareholder, Hologic, Inc (R2 Technology, Inc) License Agreement, Hologic, Inc (R2 Technology, Inc) License Agreement, Deus Technologies, LLC License Agreement, Riverain Medical License Agreement, Mitsubishi Corporation License Agreement, MEDIAN Technologies License Agreement, General Electric Company License Agreement, Toshiba Corporation Research Support, Deus Technologies, LLC Research Support, DuPont Research Support, Elbit Medical Imaging Ltd Research Support, Fuji Photo Film Co, Ltd Research Support, General Electric Company Research Support, Hitachi, Ltd Research Support, Eastman Kodak Company Research Support, Konica Minolta Group Research Support, Mitaya Manufacturing Co, Ltd Research Support, Mitsubishi Corporation Research Support, Koninklijke Philips Electronics NV Research Support, Hologic, Inc (R2 Technology, Inc) Research Support, Riverain Medical Research Support, Seiko Corporation Research Support, Siemens AG Research Support, 3M Company Research Support, Toshiba Corporation

We evaluated the usefulness of a super-high resolution (SHR) liquid crystal display (LCD) in terms of an improvement in radiologist's diagnostic accuracy in detecting clustered microcalcifications (MCLs) on digital mammograms, by use of a multi-reader multi-case receiver operating characteristic (MRMC-ROC) analysis.

Thirty digital mammograms with and 30 without clustered MCLs were selected for an observer study. Original pixel size (0.10mm) of digital mammograms was converted to the pixel size of 0.05mm by use of an interpolation method. The conventional monochrome 21 inch LCD with 3 mega-pixels and its SHR enhancement with 9 mega-pixels which was derived by an independent sub-pixel driving technique were compared. Seven radiologists participated in two reading sessions with an interval of at least one week. Reading orders of two resolutions and 60 cases were randomly selected for each observer. In both reading sessions with 3 and 9 mega-pixel resolutions, the observers were blinded in the resolution of LCDs. The MRMC-ROC analysis was used to assess the statistical significance of differences in radiologists' performance between two different resolutions of LCDs.

Preliminary results indicated that the average area under the ROC curve (AUC) for detecting clustered MCLs was slightly improved from 0.93 to 0.94 by use of the SHR-LCD with 9 mega-pixels, but there was no statistically significant difference (p=0.095). In addition, there was a slight improvement by use of SHR-LCD in terms of the number of cases correctly identified as cases with clustered MCLs (88.1% to 90.0%) and the number of false positive responses (0.31 to 0.30 per image).

The SHR-LCD has a potential to increase the sensitivity for the detection of clustered MCLs, however, the difference between the conventional LCD with 3 mega-pixels and the SHR-LCD with 9 mega-pixels was very small in terms of the improvement of diagnostic accuracy for the detection of clustered MCLs.

The clinical utility of the SHR-LCD would be demonstrated when the high-resolution digital radiography become more common, and the radiologists would become familiar with those resolutions.

Shiraishi, J, Abe, H, Ichikawa, K, Hasegawa, M, Doi, K, Evaluation of Radiologists' Performance in Detection of Clustered Microcalcifications on Digital Mammograms by Use of Super-High Resolution Liquid Crystal Display Monitors.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5001377.html