Phantom calibrations: Measurements: At 1% low-contrast,
distance accurate to 1/44th of a pixel,
and area/volume to 1/14th of a pixel.
Field-Examples:
(1) Computed Radiograph of a 2 year old female infant patient's left Tibia & Fibula were examined.
Figures 1,
2a,
2b,
& 3 illustrated that,
for example,
(i) Fig.1 - the original image of Tibia & Fibula at one angle with ROI placed on the fracture,
(ii) Fig.
2a and Fig.
2b - the 'before' and 'after' enhancement of 7x ROI,
which clearly showed the fractured part for diagnosis and accurate measurements in the enhanced image,
and (iii) Fig.3 - the annotations used for the measurements of fracture width of 3.60 pixel,
and length of 7.41 pixel.
Absolute measurement in mm could be obtained if a known width was placed near the effect & within the image plane for calibration.
Figures 4,
5a,
5b,
& 6 showed the original image of Tibia and Fibula at 90 degree with ROI placed on the injured area,
the 'before' and 'after' enhancement images and the enhanced image for the possible measurement.
(2) We analyzed 30 radial Circle of Willis MRA MIP images at 6 degree intervals demonstrating an aneurysm of the anterior communicating artery of a 72 year-old male patient.
Slice #14 at 84 degree was analyzed for its demonstration purposes: Figures 7,
8a,
8b were the analyzed images.
The enhanced image,
Figure 9 was used for the outlining for the measurement of area,
A.
A was then used to derive the Indirect Average Width,
d.
For example,
A(Slice#14)=52.82±1.06mm^2 => d(Slice#14)=2xSQR(A/(pi))=8.20mm.
Figure 10 (Table 1) listed the 30 measurements of A & d.
Figure 11 showed the graph-plots of area,
A and Indirect Average Width,
d versus Images at different angles of view.
(3) A 65 year-old male patient's liver lesion was treated with Radiofrequency Ablation (RFA) and Transcatheter Arterial Chemoembolization (TACE) and then imaged with CT to monitor the treatment progress periodically.
Figures 12,
13a,
13b,
& 14 were displayed: Figure 12 was the original image of Slice#0000****11 with ROI placed on the lesion.
Figures 13a & 13b were the 7xROI 'before' and 'after' enhancement side-by-side.
Figure 14 was the enhanced image with annotations for measurements.
155 images of nine CT scans were analyzed.
We calculated the total volume of each CT scan by adding together the areas of the 2D slices that incorporated the whole lesion.
Figure 15 (Table 2) tabulated the RFAs,
TACEs and the CT-scans that took places,
tumor volumes measured,
and their percentage changes calculated.
Figure 16 showed the graph-plot of Treatment/CT Scan versus Date.