diff --git a/include/wx/propgrid/property.h b/include/wx/propgrid/property.h
index d245dec3f9..19e16d8843 100644
--- a/include/wx/propgrid/property.h
+++ b/include/wx/propgrid/property.h
@@ -1293,7 +1293,7 @@ public:
         @remarks
         - Default behaviour is to return wxSize(0,0), which means no image.
         - Default image width or height is indicated with dimension -1.
-        - You can also return wxPG_DEFAULT_IMAGE_SIZE, i.e. wxSize(-1, -1).
+        - You can also return wxPG_DEFAULT_IMAGE_SIZE, i.e. wxDefaultSize.
     */
     virtual wxSize OnMeasureImage( int item = -1 ) const;
 
diff --git a/include/wx/propgrid/propgriddefs.h b/include/wx/propgrid/propgriddefs.h
index e25a091d60..bed733cda2 100644
--- a/include/wx/propgrid/propgriddefs.h
+++ b/include/wx/propgrid/propgriddefs.h
@@ -246,7 +246,7 @@ class wxPGValidationInfo;
 /** If property is supposed to have custom-painted image, then returning
     this in OnMeasureImage() will usually be enough.
 */
-#define wxPG_DEFAULT_IMAGE_SIZE             wxSize(-1, -1)
+#define wxPG_DEFAULT_IMAGE_SIZE  wxDefaultSize
 
 
 /** This callback function is used for sorting properties.
diff --git a/src/propgrid/advprops.cpp b/src/propgrid/advprops.cpp
index cf7de3a8d7..b0c3f4fee0 100644
--- a/src/propgrid/advprops.cpp
+++ b/src/propgrid/advprops.cpp
@@ -802,7 +802,7 @@ wxVariant wxFontProperty::ChildChanged( wxVariant& thisValue,
 /*
 wxSize wxFontProperty::OnMeasureImage() const
 {
-    return wxSize(-1,-1);
+    return wxPG_DEFAULT_IMAGE_SIZE;
 }
 
 void wxFontProperty::OnCustomPaint(wxDC& dc,
diff --git a/src/propgrid/property.cpp b/src/propgrid/property.cpp
index f141bfd9f5..20901cce8b 100644
--- a/src/propgrid/property.cpp
+++ b/src/propgrid/property.cpp
@@ -543,7 +543,7 @@ void wxPGProperty::InitAfterAdded( wxPropertyGridPageState* pageState,
 
     // Set custom image flag.
     int custImgHeight = OnMeasureImage().y;
-    if ( custImgHeight < 0 )
+    if ( custImgHeight == wxDefaultCoord )
     {
         SetFlag(wxPG_PROP_CUSTOMIMAGE);
     }
@@ -2288,7 +2288,7 @@ void wxPGProperty::DoPreAddChild( int index, wxPGProperty* prop )
                        prop );
 
     int custImgHeight = prop->OnMeasureImage().y;
-    if ( custImgHeight < 0 /*|| custImgHeight > 1*/ )
+    if ( custImgHeight == wxDefaultCoord /*|| custImgHeight > 1*/ )
         prop->m_flags |= wxPG_PROP_CUSTOMIMAGE;
 
     prop->m_parent = this;
diff --git a/src/propgrid/propgrid.cpp b/src/propgrid/propgrid.cpp
index 4c08519c20..072156b596 100644
--- a/src/propgrid/propgrid.cpp
+++ b/src/propgrid/propgrid.cpp
@@ -3777,7 +3777,8 @@ wxRect wxPropertyGrid::GetEditorWidgetRect( wxPGProperty* p, int column ) const
         {
             //m_iFlags |= wxPG_FL_CUR_USES_CUSTOM_IMAGE;
             int iw = p->OnMeasureImage().x;
-            if ( iw < 1 )
+            wxASSERT( iw == wxDefaultCoord || iw >= 0 );
+            if ( iw == wxDefaultCoord || iw == 0 )
                 iw = wxPG_CUSTOM_IMAGE_WIDTH;
             imageOffset = p->GetImageOffset(iw);
         }
@@ -3827,17 +3828,15 @@ wxSize wxPropertyGrid::GetImageSize( wxPGProperty* p, int item ) const
     else if ( item >= 0 && choiceCount == 0 )
         return wxSize(0, 0);
 
-    if ( cis.x < 0 )
+    wxASSERT( cis.x == wxDefaultCoord || cis.x >= 0 );
+    if ( cis.x == wxDefaultCoord )
     {
-        if ( cis.x <= -1 )
-            cis.x = wxPG_CUSTOM_IMAGE_WIDTH;
+        cis.x = wxPG_CUSTOM_IMAGE_WIDTH;
     }
-    if ( cis.y <= 0 )
+    wxASSERT( cis.y == wxDefaultCoord || cis.y >= 0 );
+    if ( cis.y == wxDefaultCoord || cis.y == 0 )
     {
-        if ( cis.y >= -1 )
-            cis.y = wxPG_STD_CUST_IMAGE_HEIGHT(m_lineHeight);
-        else
-            cis.y = -cis.y;
+        cis.y = wxPG_STD_CUST_IMAGE_HEIGHT(m_lineHeight);
     }
     return cis;
 }