1. Prior to starting any Bullseye or Polar Map processing one must first complete the reconstruction of the tomographic images
2. After tomographic processing, the reconstruction data is ready for bullseye processing
1. Comment - Selecting the slices to process, stress and rest, must represent the exact same area of the myocardium. Not selecting the same comparative regions or slices, will result in an inability to assess the same region
   1. Rotated map between stress and rest shifting the region. As an example, if a cold defect on stress shifts in the rest image the area on the rest might be defined as having infarct and ischemia
2. Bullseye procedure (see image below)

1. "A" selects the short axis slice
1. Select the center slice form the short axis
2. Note that all slices of the short axis, apex to base, are displayed for both stress and rest images
2. "B" setting the sagittal limits
1. The two regions are selected from the extreme medial ends of the short axis of the endocardium
2. This should not be any activity within the base or posterior walls. Another words, you are defining the chamber within the LV
3. "C" setting the oblique limits
1. The first region is set to go perpendicular through the myocardium and crosses the center of the LV cutting across the apex to base of the LV
2. The second set of regions
1. The first region is drawn just above the apex, not to include the wall of the apex
2. The second region is drawn just within the inferior and anterior wall which should include just a little activity from both walls
4. "D" the alignment angle
1. A circular is placed around the short axis
2. Arrange the radius to include the entire short axis
3. This alignment must also be at the center of the short axis
5. Processing is completed
6. Comments on Bullseye processing
1. If there are any defects within the myocardium processing becomes more difficult as you try to line up regions (stated above) especially when walls are missing. This may require a best guess that could lead to error
2. Processing is operator depending. Any minor mistakes, may drastically alter the resultant data
3. Any disease seen on a polar map should be confirmed by reviewing the reconstructed data



3. Reviewing the Bullseye maps
1. The first set of maps (stress and rest) show which coronary arteries feeds which wall of the LV
2. The second set of images shows the processing results of stress and rest images
3. To the right is a display of abnormal percents for each coronary artery
4. Also to the right is a gray scale to help assist the severity of disease. The greater the deviation of each pixel within the polar maps the greater the abnormality
5. What areas of the myocardium are considered abnormal?
6. Is there ischemia, infarct, or both?
7. If there is/are any defects, which walls within the myocardium are they?
4. More on - parts of a polar map
1. Consider this a myocardial map of the LV
2. The center of the map is the apex (or tip) of the LV with the four sides of the LV appropriately labeled around the LV
3. The map has also been labeled with the different myocardial arteries that feed LV and the anatomical structures

Coronary Arteries	Anatomical Structure of the LV
LAD - Left Anterior Descending	Septal Wall
LCX - Left Circumflex	Anterior Wall
RCA Right Coronary Artery	Inferior Wall
	Lateral Wall

1. The next image (above) shows the Bull's Eye for stress and redistribution
2. To the right of the stress and rest images is a gray scale that is a scale represents the amount of activity in each pixel, white containing the highest counts and black containing the least
3. If the pixel variation is greater than 2.5 SD then it appears dark-gray or black
4. Greater than 2.5 SD indicates complete lack of uptake within that region of the heart
5. Should a dark region be present only in the stress, but fills in at rest, then ischemia is diagnosed
6. If the dark region is seen in both stress and redistribution, then infarct is considered
7. Myocardial map shows the location of the defect and which coronary artery (or arteries) is/are involved. The only problem with this is that a high degree of patients have variations of myocardial artery location
8. Is BE = BS? Always look back at the tomographic images to confirm any possible defect seen in a Bull's Eye!

17 Segment Polar Map



Analysis of the 17 Segment Polar Map
1 - Basal Anterior	LAD	7 - Mid Anterior	LAD	13 - Apical Anterior	LAD
2 -Basal Anterior Septal	LAD	8 - Mid Anterior septal	LAD	14 - Apical Septal	LAD
3 - Basal Inferoseptal	RCA	9 - Mid Inferoseptal	RCA	15 -Apical Inferior	RCA
4 - Basal Inferior	RCA	10 - Mid Inferior	RCA	16 - Apical Inferior	LCX
5 - Basal Inferolateral	LCX	11 - Inferolateral	LCX	17 - Apex	LAD
6 - Basal Anterolateral	LCX	12 - Anterolateral	LCX


A more intensive approach is to subdivide the polar map into 17 Segments.

• The above table identifies all 17 segments
• A severity index accompanies this map which is scored 0-4
  • Normal - 0
  • Slight loss of uptake - 1
  • Reduced uptake - 2
  • Greatly reduced uptake - 3
  • No activity - 4
• Scores are summed up for rest and stress and is defined as the summed scores
• Summed difference score is the difference between stress and rest sums
  • This presences the amount of reversibility
  • Considered a semiquantitative process
• This information can displayed in the Emory ToolBox or Cedars

Finally a link for 3D display of myocardial blood flow distribution: http://www.yale.edu/imaging/anatomy/heart_sa_view/index.html

Methods for Evaluating Left Ventricular Function Computed from ECG-Gated Myocardial Perfusion SPECT