diff --git a/dap/algos/roi.py b/dap/algos/roi.py
index 708789b..efcdcab 100644
--- a/dap/algos/roi.py
+++ b/dap/algos/roi.py
@@ -1,7 +1,7 @@
 import numpy as np
 
 
-def calc_roi(results, data, pixel_mask_pf, threshold_value_choice):
+def calc_roi(results, data, pixel_mask_pf):
     if pixel_mask_pf is None:
         return
 
@@ -20,6 +20,8 @@ def calc_roi(results, data, pixel_mask_pf, threshold_value_choice):
     if not (len(roi_x1) == len(roi_x2) == len(roi_y1) == len(roi_y2)):
         return
 
+    threshold_value = results.get("threshold_value", "NaN")
+
     roi_intensities = []
     roi_intensities_normalised = []
     roi_intensities_x = []
@@ -30,7 +32,7 @@ def calc_roi(results, data, pixel_mask_pf, threshold_value_choice):
 
         roi_sum = np.nansum(data_roi)
 
-        if threshold_value_choice == "NaN":
+        if threshold_value == "NaN":
             roi_area = (ix2 - ix1) * (iy2 - iy1)
             roi_sum_norm = roi_sum / roi_area
         else:
diff --git a/dap/algos/thresh.py b/dap/algos/thresh.py
index c902348..1c18427 100644
--- a/dap/algos/thresh.py
+++ b/dap/algos/thresh.py
@@ -15,7 +15,5 @@ def calc_apply_threshold(results, data):
         if threshold_max > threshold_min:
             data[data > threshold_max] = threshold_value
 
-    return threshold_value_choice
-
 
 
diff --git a/dap/worker.py b/dap/worker.py
index b252a33..da46b21 100644
--- a/dap/worker.py
+++ b/dap/worker.py
@@ -184,9 +184,8 @@ def work(backend_address, accumulator_host, accumulator_port, visualisation_host
         if pixel_mask_pf is not None:
             pfdata[pixel_mask_pf != 1] = np.nan
 
-        threshold_value_choice = calc_apply_threshold(results, pfdata)
-
-        calc_roi(results, pfdata, pixel_mask_pf, threshold_value_choice)
+        calc_apply_threshold(results, pfdata)
+        calc_roi(results, pfdata, pixel_mask_pf)
         calc_spi_analysis(results)
         calc_peakfinder_analysis(results, pfdata, pixel_mask_pf)