diff --git a/zUtil_TomoUtils/GtMultiVolView.m b/zUtil_TomoUtils/GtMultiVolView.m
index 3be7806422d40a847d7563cf720985cc644b55d2..2ac862da34e29d9e0f2f5154e2fc04275b406831 100644
--- a/zUtil_TomoUtils/GtMultiVolView.m
+++ b/zUtil_TomoUtils/GtMultiVolView.m
@@ -102,7 +102,10 @@ classdef GtMultiVolView < GtVolView
         function vol = getMultiVol(vols, index)
             if (iscell(vols))
                 if (index == 0)
-                    vol = sum(cat(4, vols{:}), 4);
+                    vol = vols{1};
+                    for n = 2:numel(vols)
+                        vol = vol + vols{n};
+                    end
                 else
                     vol = vols{index};
                 end