diff --git a/chromadb/proto/convert.py b/chromadb/proto/convert.py
index 17ca55a83b9..9d3d7deaae1 100644
--- a/chromadb/proto/convert.py
+++ b/chromadb/proto/convert.py
@@ -36,6 +36,12 @@
     VectorQueryResult,
 )
 
+_SEGMENT_SCOPE_FAST_MAP = {
+    chroma_pb.SegmentScope.VECTOR: SegmentScope.VECTOR,
+    chroma_pb.SegmentScope.METADATA: SegmentScope.METADATA,
+    chroma_pb.SegmentScope.RECORD: SegmentScope.RECORD,
+}
+
 
 class ProjectionRecord(TypedDict):
     id: str
@@ -158,18 +164,16 @@ def from_proto_submit(
 
 
 def from_proto_segment(segment: chroma_pb.Segment) -> Segment:
+    has_metadata = segment.HasField("metadata")
+    file_paths = {name: list(paths.paths) for name, paths in segment.file_paths.items()}
+
     return Segment(
         id=UUID(hex=segment.id),
         type=segment.type,
-        scope=from_proto_segment_scope(segment.scope),
+        scope=_from_proto_segment_scope_fast(segment.scope),
         collection=UUID(hex=segment.collection),
-        metadata=from_proto_metadata(segment.metadata)
-        if segment.HasField("metadata")
-        else None,
-        file_paths={
-            name: [path for path in paths.paths]
-            for name, paths in segment.file_paths.items()
-        },
+        metadata=from_proto_metadata(segment.metadata) if has_metadata else None,
+        file_paths=file_paths,
     )
 
 
@@ -686,3 +690,12 @@ def from_proto_knn_batch_result(
         [from_proto_knn_projection_record(record) for record in result.records]
         for result in results.results
     ]
+
+
+def _from_proto_segment_scope_fast(
+    segment_scope: chroma_pb.SegmentScope,
+) -> SegmentScope:
+    try:
+        return _SEGMENT_SCOPE_FAST_MAP[segment_scope]
+    except KeyError:
+        raise RuntimeError(f"Unknown segment scope {segment_scope}")