From 389da53da4ffbae9166cf8bd454b4bf9b73674da Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 20 Nov 2025 15:55:29 +0000
Subject: [PATCH 1/3] Initial plan


From 781097d14400901cff0f962c5138552a30483e8d Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 20 Nov 2025 16:00:30 +0000
Subject: [PATCH 2/3] Add caching for referenced CT series UIDs to improve
 performance

Co-authored-by: fedorov <313942+fedorov@users.noreply.github.com>
---
 .../SegmentationComparison.py                 | 22 ++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/SegmentationComparison/SegmentationComparison.py b/SegmentationComparison/SegmentationComparison.py
index 5d5b241..3663544 100644
--- a/SegmentationComparison/SegmentationComparison.py
+++ b/SegmentationComparison/SegmentationComparison.py
@@ -1414,6 +1414,8 @@ def __init__(self) -> None:
         """Called when the logic class is instantiated. Can be used for initializing member variables."""
         ScriptedLoadableModuleLogic.__init__(self)
         self.segmentBoundingBoxes = {}
+        # Cache for referenced CT series UIDs to avoid repeated DICOM file reads
+        self._referencedSeriesCache = {}
 
     def setDefaultParameters(self, parameterNode):
         """
@@ -1748,24 +1750,42 @@ def getLayoutXML(self, viewNumber, threedCheckbox, twodCheckbox, layout, viewNam
     
         return layout_xml
     
+    def clearReferencedSeriesCache(self):
+        """
+        Clears the cache of referenced CT series UIDs.
+        Should be called when the DICOM database is updated or modified.
+        """
+        self._referencedSeriesCache.clear()
+    
     #Load all Segmentation files for chosen Volume
     def getReferencedCtSeries(self, segmentation_uid):
         """
         Returns the SeriesInstanceUID of the referenced CT given a DICOM Seg File.
+        Uses caching to avoid repeated DICOM file reads for the same series.
         :param segmentation_uid: SeriesInstanceUID of a segmentation:
 
         :return String: SeriesInstanceUID of the referecned CT
         """
+        # Check cache first
+        if segmentation_uid in self._referencedSeriesCache:
+            return self._referencedSeriesCache[segmentation_uid]
+        
         dicom_database = slicer.dicomDatabase
         series_files = dicom_database.filesForSeries(segmentation_uid)
         if not series_files:
+            self._referencedSeriesCache[segmentation_uid] = None
             return None
         
         try:
             ds = pydicom.dcmread(series_files[0], stop_before_pixels = True, specific_tags = ["ReferencedSeriesSequence"])
-            return ds.ReferencedSeriesSequence[0].SeriesInstanceUID
+            referenced_series = ds.ReferencedSeriesSequence[0].SeriesInstanceUID
+            # Cache the result
+            self._referencedSeriesCache[segmentation_uid] = referenced_series
+            return referenced_series
         except Exception as e:
             print(e)
+            # Cache None for failed reads to avoid repeated failures
+            self._referencedSeriesCache[segmentation_uid] = None
             return None
         
     def getSegmentationSopInstanceUID(self, series_uid):

From 49c721fa23b0d78b967c91e446b38d91f879f94a Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 20 Nov 2025 16:05:01 +0000
Subject: [PATCH 3/3] Improve cache comment to clarify the mapping structure

Co-authored-by: fedorov <313942+fedorov@users.noreply.github.com>
---
 SegmentationComparison/SegmentationComparison.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/SegmentationComparison/SegmentationComparison.py b/SegmentationComparison/SegmentationComparison.py
index 3663544..d62108c 100644
--- a/SegmentationComparison/SegmentationComparison.py
+++ b/SegmentationComparison/SegmentationComparison.py
@@ -1414,7 +1414,8 @@ def __init__(self) -> None:
         """Called when the logic class is instantiated. Can be used for initializing member variables."""
         ScriptedLoadableModuleLogic.__init__(self)
         self.segmentBoundingBoxes = {}
-        # Cache for referenced CT series UIDs to avoid repeated DICOM file reads
+        # Cache for referenced CT series UIDs to avoid repeated DICOM file reads.
+        # Maps segmentation series UID -> referenced CT series UID
         self._referencedSeriesCache = {}
 
     def setDefaultParameters(self, parameterNode):