function output = getMaskCoordinates(obj, maskSuffix)
  mask = obj.loadMask(maskSuffix);
  maskIndices = find(mask);
  slicePixelCoordinates = obj.loadPixelCoordinates();
  maskCoordinates = [...
    slicePixelCoordinates.x(maskIndices),...
    slicePixelCoordinates.y(maskIndices),...
    slicePixelCoordinates.z(maskIndices)];
  output = maskCoordinates;
end