diff --git a/fsl/data/model.py b/fsl/data/model.py
index ededc41a58814eb78d5c9e9144affba05c600d3c..13b3510e607966a39ba2edb70428cf64012a0ea8 100644
--- a/fsl/data/model.py
+++ b/fsl/data/model.py
@@ -23,6 +23,8 @@ import numpy   as np
 
 import six
 
+from . import image as fslimage
+
 
 log = logging.getLogger(__name__)
 
@@ -149,3 +151,38 @@ def loadVTKPolydataFile(infile):
         indexOffset        += polygonLengths[i]
 
     return vertices, polygonLengths, indices
+
+
+def getFIRSTPrefix(modelfile):
+    """If the given ``vtk`` file was generated by `FIRST
+    <https://fsl.fmrib.ox.ac.uk/fsl/fslwiki/FIRST>`_, this function
+    will return the file prefix. Otherwise an ``Exception`` will be
+    raised.
+    """
+
+    if not modelfile.endswith('first.vtk'):
+        raise ValueError('Not a first vtk file: {}'.format(modelfile))
+
+    modelfile = op.basename(modelfile)
+    prefix    = modelfile.split('-')
+    prefix    = '-'.join(prefix[:-1])
+
+    return prefix
+
+
+def findReferenceImage(modelfile):
+    """Given a ``vtk`` file, attempts to find a corresponding ``NIFTI``
+    image file. Return the path to the image, or ``None`` if no image was
+    found.
+
+    Currently this function will only return an image for ``vtk`` files
+    generated by `FIRST <https://fsl.fmrib.ox.ac.uk/fsl/fslwiki/FIRST>`_.
+    """
+
+    try:
+
+        prefix = getFIRSTPrefix(modelfile)
+        return fslimage.addExt(prefix, mustExist=True)
+
+    except:
+        return None
diff --git a/fsl/utils/async.py b/fsl/utils/async.py
index 4b835e28e5c156f9c8008e4912a5145d944e154b..4b403d794e101daf666acbb2731218d532784e99 100644
--- a/fsl/utils/async.py
+++ b/fsl/utils/async.py
@@ -372,7 +372,7 @@ def idle(task, *args, **kwargs):
 
     .. note:: You will run into difficulties if you schedule a function that
               expects/accepts its own keyword arguments called ``name``,
-              ``skipIfQueued``, ``after``, or ``timeout``.
+              ``skipIfQueued``, ``after``, ``timeout``, or ``alwaysQueue``.
     """
 
     global _idleRegistered