diff --git a/extensions/cornerstone-dicom-seg/src/viewports/OHIFCornerstoneSEGViewport.tsx b/extensions/cornerstone-dicom-seg/src/viewports/OHIFCornerstoneSEGViewport.tsx
index 0df1a29da..2f5ccb95e 100644
--- a/extensions/cornerstone-dicom-seg/src/viewports/OHIFCornerstoneSEGViewport.tsx
+++ b/extensions/cornerstone-dicom-seg/src/viewports/OHIFCornerstoneSEGViewport.tsx
@@ -344,10 +344,10 @@ function OHIFCornerstoneSEGViewport(props) {
             patientSex: PatientSex || '',
             patientAge: PatientAge || '',
             MRN: PatientID || '',
-            thickness: SliceThickness ? `${SliceThickness.toFixed(2)}mm` : '',
+            thickness: SliceThickness ? `${parseFloat(SliceThickness).toFixed(2)}mm` : '',
             spacing:
               SpacingBetweenSlices !== undefined
-                ? `${SpacingBetweenSlices.toFixed(2)}mm`
+                ? `${parseFloat(SpacingBetweenSlices).toFixed(2)}mm`
                 : '',
             scanner: ManufacturerModelName || '',
           },