Fix Standalone Viewer

OHIFViewer/client/components/viewer/viewer.js

@@ -120,7 +120,7 @@ Template.viewer.onCreated(() => {
         const studyMetadata = new OHIF.metadata.StudyMetadata(study, study.studyInstanceUid);
         let displaySets = study.displaySets;
 
-        if(!displaySets) {
+        if(!study.displaySets) {
             displaySets = OHIF.viewerbase.sortingManager.getDisplaySets(studyMetadata);
             study.displaySets = displaySets;
         }