# Wavelia Breast Imaging: The Optical Breast Contour Detection Subsystem
## 3 Results and Discussion
### D Breast Surface Reconstruction: Indicative Results from the First Ten Patient Scans  
In Figures 33 and 34, the reconstructed breast surfaces using the Wavelia OBCD subsystem are shown for the ten first patients enrolled in the on-going first in-human clinical investigation of the Wavelia system, at Galway University Hospital. These are preliminary clinical results which serve to demonstrate the efficacy of the presented calibration algorithm and 3D breast surface reconstruction method on real clinical data. It is demonstrated that meaningful breast surfaces of good quality have been achieved for all the ten patient scans. In Figures 33 and 34, two views of the reconstructed surface of both breasts of each patient are shown. The two selected views for this illustration are: (a) a side view of the two pendulums breasts: looking at the patient from the front; (b) a supine-mimicking view of the two breasts: looking at the patient from the bottom. This comparative presentation of the breast anatomy for this group of ten patients, as captured during their Wavelia OBCD scans, highlights the expected variability in the positioning of the patients. Even though the same positioning of the arms and alignment of the \begin{table}
\begin{tabular}{l c c c c c c c} \hline  & **B1 Test 1** & **B1 Test 2** & **B1 Test 3** & **B1 Test 4** & **B2 Test 1** & **B2 Test 2** & **B2 Test 3** & **B2 Test 4** \\ \hline Total number of points on the extracted breast surface & 177,228 & 178,570 & 178,562 & 179,896 & 134,808 & 137,000 & 119,758 & 119,748 \\ Percentage of points with & 76.80 & 90.20 & 89.01 & 87.28 & 82.18 & 93.77 & 83.88 & 79.88 \\ distance error \(<=\) 0.0 mm (\%) & 96.26 & 95.19 & 94.58 & 97.45 & 100 & 99.14 & 98.12 & 99.77 \\ Percentage of points with & 97.55 & 97.42 & 97.37 & 98.94 & 100 & 100 & 99.86 & 99.93 \\ Percentage of points with & 2.45 & 2.58 & 2.63 & 1.06 & 0.00 & 0.00 & 0.14 & 0.07 \\ RMS distance error (mm) & 0.74 & 0.65 & 0.69 & 0.50 & 0.40 & 0.30 & 0.44 & 0.42 \\ Reference Vertical Extent of the Breast (mm) & 110.19 & 110.96 & 110.96 & 111.16 & 84.67 & 84.97 & 67.88 & 67.59 \\ Computed Vertical Extent of the Breast (mm) & 109.36 & 109.55 & 109.60 & 109.85 & 84.71 & 84.79 & 67.73 & 67.50 \\ Error in the Vertical Extent of the Breast (mm) & \(-\)0.83 & \(-\)1.41 & \(-\)1.36 & \(-\)1.31 & 0.04 & \(-\)0.19 & \(-\)0.15 & \(-\)0.09 \\ Reference Volume of the Breast (mL) & 915.57 & 924.57 & 924.57 & 928.28 & 498.92 & 502.51 & 349.48 & 350.01 \\ Computed Volume of the Breast (mL) & 909.81 & 921.25 & 921.25 & 921.97 & 494.27 & 502.21 & 349.51 & 347.48 \\ Breast Volume Error (mL) & \(-\)5.75 & \(-\)3.31 & \(-\)3.31 & \(-\)6.31 & \(-\)4.64 & \(-\)0.31 & 0.03 & \(-\)2.52 \\ Breast Volume Error (\%) & \(-\)0.63 & \(-\)0.36 & \(-\)0.36 & \(-\)0.68 & \(-\)0.93 & \(-\)0.06 & 0.01 & \(-\)0.72 \\ \hline \end{tabular}
\end{table} 
Table 2: Summary of the accuracy results on eight 3D breast surface reconstruction tests involving the B1 and B2 breast phantoms. patient's body with the bed is intended in all cases, unavoidable rotations of the breasts and/or twist of the torso seem to happen in the case of some patients. Figure 33: Breast Anatomy, as seen in the Wavelia OBCD scanner: Side view (**Left**), Supine position mimicking view (**Right**) - the first five patient scans. While a quantitative evaluation of the reconstructed surfaces is not straightforward in the case of the patient scans, the computation of the breast volume, as performed using the Wavelia OBCD scan data, has been possible to be validated using as reference the X-ray mammography breast volume data, being made available for the same patients. Figure 34: Breast Anatomy, as seen in the Wavelia OBCD scanner: Side view (**Left**), Supine position mimicking view (**Right**) - the second series of five patient scans. All the patients enrolled in the clinical study have had an X-ray mammogram performed no more than 6 weeks ahead of their scan with the Wavelia prototype medical device.