fix: segmentation not loading (#1566)

* Fix bug

* Refactor the state of the component RTPanel

platform/core/src/classes/metadata/StudyMetadata.js

@@ -78,7 +78,7 @@ export class StudyMetadata extends Metadata {
     Object.defineProperty(this, 'studyInstanceUID', {
       configurable: false,
       enumerable: false,
-      get: function() {
+      get: function () {
         return this.getStudyInstanceUID();
       },
     });
@@ -208,20 +208,21 @@ export class StudyMetadata extends Metadata {
   /**
    * Returns a list of derived datasets in the study, filtered by the given filter.
    * @param {object} filter An object containing search filters
-   * @param {object} filter.modality
+   * @param {object} filter.Modality
    * @param {object} filter.referencedSeriesInstanceUID
    * @param {object} filter.referencedFrameOfReferenceUID
    * @return {Array} filtered derived display sets
    */
   getDerivedDatasets(filter) {
     const {
-      modality,
+      Modality,
       referencedSeriesInstanceUID,
       referencedFrameOfReferenceUID,
     } = filter;
+
     let filteredDerivedDisplaySets = this._derivedDisplaySets;
 
-    if (modality) {
+    if (Modality) {
       filteredDerivedDisplaySets = filteredDerivedDisplaySets.filter(
         displaySet => displaySet.Modality === Modality
       );