diff --git a/plotting/matRad_plotVoiContourSlice.m b/plotting/matRad_plotVoiContourSlice.m
index 604b774d6..02062341e 100644
--- a/plotting/matRad_plotVoiContourSlice.m
+++ b/plotting/matRad_plotVoiContourSlice.m
@@ -80,7 +80,7 @@
             C = cst{s,7}{slice,plane};
         else
             %If we do not have precomputed contours available, then compute them
-            mask = zeros(size(ct{ctIndex}));
+            mask = zeros(ct.cubeDim);
             mask(cst{s,4}{ctIndex}) = 1;
             
             if plane == 1 && any(any(mask(slice,:,:) > 0))
diff --git a/tools/matRad_plotSliceWrapper.m b/tools/matRad_plotSliceWrapper.m
index feffef7a8..698e84dd4 100644
--- a/tools/matRad_plotSliceWrapper.m
+++ b/tools/matRad_plotSliceWrapper.m
@@ -117,7 +117,7 @@
 
 %plot VOI contours
 if  ~isempty(cst)
-    hContour = matRad_plotVoiContourSlice(axesHandle,cst,ct.cubeHU,cubeIdx,voiSelection,plane,slice,contourColorMap,varargin{:});
+    hContour = matRad_plotVoiContourSlice(axesHandle,cst,ct,cubeIdx,voiSelection,plane,slice,contourColorMap,varargin{:});
 
 if boolPlotLegend
    visibleOnSlice = (~cellfun(@isempty,hContour));