diff --git a/readimc/mcd_file.py b/readimc/mcd_file.py
index d49ed0b..6815e9a 100644
--- a/readimc/mcd_file.py
+++ b/readimc/mcd_file.py
@@ -199,6 +199,7 @@ def read_slide(self, slide: Slide) -> Optional[np.ndarray]:
         if data_start_offset == data_end_offset == 0:
             return None
         data_start_offset += 161
+        data_end_offset -= 1
         if data_start_offset >= data_end_offset:
             raise IOError(
                 f"MCD file '{self.path.name}' corrupted: "
@@ -230,6 +231,7 @@ def read_panorama(self, panorama: Panorama) -> np.ndarray:
                 f"cannot locate image data for panorama {panorama.id}"
             ) from e
         data_start_offset += 161
+        data_end_offset -= 1
         if data_start_offset >= data_end_offset:
             raise IOError(
                 f"MCD file '{self.path.name}' corrupted: "
@@ -270,6 +272,7 @@ def read_before_ablation_image(
         if data_start_offset == data_end_offset == 0:
             return None
         data_start_offset += 161
+        data_end_offset -= 1
         if data_start_offset >= data_end_offset:
             raise IOError(
                 f"MCD file '{self.path.name}' corrupted: "
@@ -312,6 +315,7 @@ def read_after_ablation_image(
         if data_start_offset == data_end_offset == 0:
             return None
         data_start_offset += 161
+        data_end_offset -= 1
         if data_start_offset >= data_end_offset:
             raise IOError(
                 f"MCD file '{self.path.name}' corrupted: "