Digital Database for Screening Mammography

This table contains links to overview pages for the cases in this volume. Each overview page contains the ics file, "thumbnails" of the images associated with the case, and the overlay markings of the abnormalities. The "thumbnail" images are meant for visual browsing of the cases only, and are not suitable for any form of experimental work. The thumbnail images were blurred, subsampled, sharpened and converted to eight bits per pixel. Thus, they contain artifacts introduced by this processing (i.e., aliasing, ringing, re-quantization, clipping etc.). Any experimental work should start with the full raw images for the case.

Benign case are formed from screening exams in which something suspicious was found, but was determined to not be malignant. The determination of benign condition was most often made by pathology. However, in some cases, ultrasound or some other accepted means was used to determine benign condition. Thus, in the overlay file, the field name "PATHOLOGY" should not be read to imply that every benign abnormality was sent to pathology. The choice of field name was made early in the project, and is maintained for compatibility with earlier versions of the database. The outlines of all suspicious regions have been transcribed from markings made by an experienced mammographer. In almost all cases, an abnormality is visible in both views of the breast. However, there are a cases where an abnormality seen in one view is not visible in the other view. This is most often due to the fact that the CC and MLO views do not image exactly the same tissue, but in some cases the abnormality may simply not present any visible signs in one view.

The "ics" header file contains the following information. The "DATE_OF_STUDY" field gives the date that the mammogram was performed. The "PATIENT_AGE" field gives the age of the patient at the time that the mammogram was performed. The "DENSITY" field gives an ACR BI-RADS breast density rating for the case, as assigned by an experienced mammographer. The "DIGITIZER" field indicates the equipment used to digitize the mammogram films. The "LEFT_CC," "LEFT_MLO," RIGHT_CC," and "RIGHT_MLO" fields specify the size of the corresponding images and whether or not a file exists for the overlay of abnormality outlines. The "FILM," "FILM_TYPE," "SEQUENCE" and "DATE_DIGITIZED" fields should be disregarded. They are being maintained for compatibility with earlier versions of the database, but do not contain useful information.

The individual overlay files contain keywords to describe each abnormality. They also contain an ACR BI-RADS assessment code for each abnormality. And they contain a mammographer-assigned "subtlety rating" on a scale of 1 to 5, where 1 is "subtle" and 5 is "obvious." A case that has a value `0' in Assessment field represents a case with "Assessment Is Incomplete".According to BI-RADS by ACR, "Assessment Is Incomplete" is summarized as follows; 'Finding for Which Additional Evaluation is Needed': This is almost always used in a screening situation and should rarely be used after a full imaging work up. A recommendation for additional evaluation should be made including the use of spot compression, magnification, special mammographic views, ultrasound, aspiration, etc. Whenever possible, the present mammogram should be compared to previous stuides. The radiologist should use judgment in how vigorously to pursue previous studies. The mammographer was not constrained to provide the same keyword description for a given abnormality in each view. Unusual objects (e.g., pacemaker, breast implant) may be visible in some images. These are not identified by an overlay file.

We strongly encourage that whenever research results are presented using cases from this database, a histogram of the subtlety rating of the images used in the research also be presented.

You can order the complete volume on tape. Click here for an order form. Please note that you should be using the lastest version of DDSMView to view the complete cases. You can get it here or from our ftp site (figment.csee.usf.edu) in the directory "pub/DDSM/software/bin" using anonymous ftp.