diff --git a/ivadomed/loader/utils.py b/ivadomed/loader/utils.py
index 59e2a55b8..956dceb65 100644
--- a/ivadomed/loader/utils.py
+++ b/ivadomed/loader/utils.py
@@ -13,7 +13,6 @@
 import torch
 from loguru import logger
 from sklearn.model_selection import train_test_split
-from torch._six import string_classes
 from ivadomed import utils as imed_utils
 from ivadomed.keywords import SplitDatasetKW, LoaderParamsKW, ROIParamsKW, ContrastParamsKW
 import nibabel as nib
@@ -270,7 +269,7 @@ def imed_collate(batch: dict) -> dict | list | str | torch.Tensor:
         return torch.LongTensor(batch)
     elif isinstance(batch[0], float):
         return torch.DoubleTensor(batch)
-    elif isinstance(batch[0], string_classes):
+    elif isinstance(batch[0], str):
         return batch
     elif isinstance(batch[0], collections.abc.Mapping):
         return {key: imed_collate([d[key] for d in batch]) for key in batch[0]}
diff --git a/requirements.txt b/requirements.txt
index 5adb8ba78..e034e39a7 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -11,12 +11,12 @@ imageio>=2.31.4
 joblib~=1.0
 matplotlib>=3.3.0
 nibabel~=3.2
-onnxruntime~=1.7
+onnx
+# 1.7.0>onnxruntime>=1.5.1 required `brew install libomp` on macOS.
+# So, pin to >=1.7.0 to avoid having to ask users to install libomp.
+# Avoid version 1.16.0 due to: https://github.com/spinalcordtoolbox/spinalcordtoolbox/issues/4225
+onnxruntime>=1.7.0,!=1.16.0
 pandas>=1.1,<1.5.0
-# We pin Pillow here because we're currently using an older version of `torch`, which in turn uses an
-# older version of `tensorboard`, which in turn uses a deprecated feature of Pillow.
-# Once we update `torch`, the deprecated call will be removed, and we can then unpin Pillow.
-Pillow<10.0.0
 pybids>=0.14.0,<0.15.6
 scikit-learn>=0.20.3
 scikit-image~=0.17
@@ -25,6 +25,6 @@ tensorboard>=1.15.0
 tqdm>=4.30
 scipy
 torchio>=0.18.68
-torch>=1.8.1,<=1.11.0
-torchvision>=0.9.1,<=0.12.0
+torch>=1.8.1
+torchvision>=0.9.1
 wandb>=0.12.11