# Presentation: 239310

## LIDC Radiologists’ Markings

- A Multiple Reader/ Multiple Session Process
- Blinded Read
- 	Each Radiologist reads independently
- 	 (Blinded to other readers’ markings)
- Unblinded Read
- 	Each Radiologist re-reads, but is shown their own blinded read markings as well as blinded read markings of other radiologists reading the same case (unblinded to other reader’s markings).
- Note: No forced consensus at blinded OR unblinded read

## LIDC Radiologists’ Markings

- Nodules > 3mm:
- Contour complete nodule volume,
- Provide subjective ratings
- Nodules < 3mm:
- Mark centroid only, no ratings
- Non-Nodules > 3mm:
- Mark centroid only, no ratings
- Non-Nodules < 3mm:
- Not marked at all

## The Blinded Read

- Original Image

- Reader has marked a Non-Nodule > 3mm

- Original Image

- Reader has marked a Non-Nodule > 3mm

- Original Image

## Zoom in and determine whether less than 3 mm

- Reader has marked a Nodule < 3mm

- Suspicious Object

**Zoom in and determine whether less than 3 mm**

- Reader has marked a Nodule < 3mm

- Two very obvious nodules

- In this tool, semiautomated contouring is used to obtain its boundary.

## Note Nodule List

- Reader now marks 2nd nodule boundary

## End Blinded Reading Session

- Writes xml file
- Saves Contours of Nodules > 3mm
- Saves locations of Nodules < 3mm
- Saves Locations of Non-Nodules > 3mm
- Other info.

## UnBlinded Reading Session

- Begins when all assigned radiologists have completed blinded read
- Read in xml files that represent  blinded reads
- NOTE: _**No forced consensus**_ on either location of nodules nor on boundaries.

## UnBlinded Reading Session

- Read ALL markings
- Decide which to keep
- Can keep, delete or revise their own
- Can reject/delete other’s markings
- Can copy other’s markings (for non-Nods or Nod < 3mm)
- Create their own contours based on others’ markings (for Nod > 3mm)

- Note Worklist of all markings from all readers.
-  This reader’s own markings show as blue in color box;
- Markings of the same object are grouped together either in green or white background

- Scars in the Lung Apices
-  Only one marking per object is shown

- Scars in the Lung Apices
-  Show all markings for each object

- Scar extending over several slices

- Scar extending over several slices

- Scar marked by one reader at this location

- Scar marked by another reader at this location

- Marked by one reader as a nodule < 3mm at this location

- Non Nodule over several slices

- Marked by one reader at this location

- Marked by another reader at this location

- Nodule < 3mm  marked by one reader at this location

- Obvious Nodule

## Zoom in on nodule

## Show one radiologist’s contour

## Show another radiologist’s contour

**Show another radiologist’s contour**

## Show another radiologist’s contour

**Show another radiologist’s contour**

## Show another radiologist’s contour

**Show another radiologist’s contour**

## Markings of Several Readers

- No Forced Consensus
- However, Reader can modify their own boundaries on UBR, if they wish (This screen shows going back to the contour creation/editing tools)

## We are also collecting Radiologists’ subjective assessment of nodules > 3mm in terms of shape, density, etc.

**We are also collecting Radiologists’ subjective assessment of nodules > 3mm in terms of shape, density, etc.**

- End Reading Session

## End UnBlinded Reading Session

- When ALL markings have either been confirmed or rejected, write the xml file from this reader that:
- Saves final contours of Nodules > 3mm
- Saves final subjective Ratings for Nodules > 3mm
- Saves final locations of Nodules < 3mm
- Saves final locations of Non-Nodules > 3mm
- Other bookkeeping info (institution of reader, etc.)