diff --git a/src/scilpy/cli/scil_json_convert_entries_to_xlsx.py b/src/scilpy/cli/scil_json_convert_entries_to_xlsx.py
index 98b5903f3..21e801970 100755
--- a/src/scilpy/cli/scil_json_convert_entries_to_xlsx.py
+++ b/src/scilpy/cli/scil_json_convert_entries_to_xlsx.py
@@ -17,7 +17,7 @@
 from scilpy.version import version_string
 
 dps_dpp = ['data_per_streamline_keys', 'data_per_point_keys']
-
+required_keys = {'mean', 'std'}
 
 def _get_all_bundle_names(stats):
     bnames = set()
@@ -82,7 +82,7 @@ def _get_stats_parse_function(stats, stats_over_population):
         return _parse_lesion
     elif type(first_bundle_substat) is dict:
         sub_keys = list(first_bundle_substat.keys())
-        if set(sub_keys) == set(['mean', 'std']):  # when you have mean and std per stats
+        if required_keys.issubset(sub_keys):  # when you have mean and std per stats
             if stats_over_population:
                 return _parse_per_label_population_stats
             else:
@@ -126,7 +126,7 @@ def _parse_scalar_stats(stats, subs, bundles):
     return dataframes, df_names
 
 
-def _parse_scalar_meanstd(stats, subs, bundles):
+def _parse_scalar_meanstd(stats, subs, bundles, optional_keys):
     metric_names = _get_metrics_names(stats)
 
     nb_subs = len(subs)
@@ -135,6 +135,20 @@ def _parse_scalar_meanstd(stats, subs, bundles):
 
     means = np.full((nb_subs, nb_bundles, nb_metrics), np.NaN)
     stddev = np.full((nb_subs, nb_bundles, nb_metrics), np.NaN)
+    
+    found_keys = set()
+    for sub_dict in stats.values():
+        for bundle_dict in sub_dict.values():
+            for m_stat in bundle_dict.values():
+                if isinstance(m_stat, dict):
+                    found_keys.update(m_stat.keys())
+    keys_present = set(optional_keys).intersection(found_keys)
+    optional_arrays = {}
+
+    for key in keys_present:
+        optional_arrays[key] = np.full(
+            (nb_subs, nb_bundles, nb_metrics),
+            np.nan)
 
     for sub_id, sub_name in enumerate(subs):
         for bundle_id, bundle_name in enumerate(bundles):
@@ -147,6 +161,9 @@ def _parse_scalar_meanstd(stats, subs, bundles):
                     if m_stat is not None:
                         means[sub_id, bundle_id, metric_id] = m_stat['mean']
                         stddev[sub_id, bundle_id, metric_id] = m_stat['std']
+                        for key in keys_present:
+                            optional_arrays[key][sub_id, bundle_id, metric_id] = \
+                                m_stat.get(key, np.nan)
 
     dataframes = []
     df_names = []
@@ -157,8 +174,16 @@ def _parse_scalar_meanstd(stats, subs, bundles):
         df_names.append(metric_name + "_mean")
 
         dataframes.append(pd.DataFrame(data=stddev[:, :, metric_id],
-                                       index=subs, columns=bundles))
+                                        index=subs, columns=bundles))
         df_names.append(metric_name + "_std")
+        
+        for key in keys_present:
+            dataframes.append(
+                pd.DataFrame(
+                    data=optional_arrays[key][:, :, metric_id],
+                    index=subs,
+                    columns=bundles))
+            df_names.append(f"{metric_name}_{key}")
 
     return dataframes, df_names
 
@@ -199,7 +224,7 @@ def _parse_scalar_lesions(stats, subs, bundles):
     return dataframes, df_names
 
 
-def _parse_stats(stats, subs, bundles):
+def _parse_stats(stats, subs, bundles, optional_keys=None):
     nb_subs = len(subs)
     nb_bundles = len(bundles)
 
@@ -408,7 +433,8 @@ def _parse_per_label_population_stats(stats, bundles, metrics):
 def _create_xlsx_from_json(json_path, xlsx_path,
                            sort_subs=True, sort_bundles=True,
                            ignored_bundles_fpath=None,
-                           stats_over_population=False):
+                           stats_over_population=False,
+                           optional_keys=None):
     with open(json_path, 'r') as json_file:
         stats = json.load(json_file)
 
@@ -428,7 +454,7 @@ def _create_xlsx_from_json(json_path, xlsx_path,
 
     cur_stats_func = _get_stats_parse_function(stats, stats_over_population)
 
-    dataframes, df_names = cur_stats_func(stats, subs, bundle_names)
+    dataframes, df_names = cur_stats_func(stats, subs, bundle_names, optional_keys)
 
     if len(dataframes):
         _write_dataframes(dataframes, df_names, xlsx_path)
@@ -447,6 +473,9 @@ def _build_arg_parser():
 
     p.add_argument('--no_sort_subs', action='store_false',
                    help='If set, subjects won\'t be sorted alphabetically.')
+    
+    p.add_argument('--extra_key', nargs='+', default=[],
+                   help='Optional keys to export (must be associated to numeric values only)')
 
     p.add_argument('--no_sort_bundles', action='store_false',
                    help='If set, bundles won\'t be sorted alphabetically.')
@@ -468,6 +497,7 @@ def main():
     parser = _build_arg_parser()
     args = parser.parse_args()
     logging.getLogger().setLevel(logging.getLevelName(args.verbose))
+    extra_keys = set(args.extra_key)
 
     assert_inputs_exist(parser, args.in_json)
     assert_outputs_exist(parser, args, args.out_xlsx)
@@ -476,7 +506,8 @@ def main():
                            sort_subs=args.no_sort_subs,
                            sort_bundles=args.no_sort_bundles,
                            ignored_bundles_fpath=args.ignore_bundles,
-                           stats_over_population=args.stats_over_population)
+                           stats_over_population=args.stats_over_population,
+                           optional_keys=extra_keys)
 
 
 if __name__ == "__main__":