diff --git a/scikits/image/io/qt_plugin.py b/scikits/image/io/qt_plugin.py
index fd47eb86..9de1ea7f 100644
--- a/scikits/image/io/qt_plugin.py
+++ b/scikits/image/io/qt_plugin.py
@@ -37,7 +37,7 @@ else:
     def show(arr, block=True):
         global app
 
-        if not '-qt4thread' in sys.argv and app is None:
+        if not '-q4thread' in sys.argv and app is None:
             app = QApplication([])
 
         arr = prepare_for_display(arr)