diff --git a/ligo/skymap/postprocess/find_injection.py b/ligo/skymap/postprocess/find_injection.py
index abcbe834b5c1c9c23b7d35f727234d57a7d24245..448111b84952c3cf3d951b0abd0eb62bbb3bf20e 100644
--- a/ligo/skymap/postprocess/find_injection.py
+++ b/ligo/skymap/postprocess/find_injection.py
@@ -226,8 +226,9 @@ def find_injection_moc(sky_map, true_ra=None, true_dec=None, true_dist=None,
         d_r = max_r / n_r
         r = d_r * np.arange(1, n_r)
 
-        # Calculate volume of frustum-shaped voxels with distance centered on r
-        # and extending from (r - d_r) to (r + d_r).
+        # Calculate volume of each voxel, defined as the region within the
+        # HEALPix pixel and contained within the two centric spherical shells
+        # with radii (r - d_r) and (r + d_r).
         dV = (2 / 3 * (3 * np.square(r) + np.square(d_r))
               * d_r * dA.reshape(-1, 1))