The following anatomic variations can make the translabyrinthine approach much more difficult and at times impossible.

Considerable anatomic variation exists in the Circle of Willis.

There is anatomic variation between the hearts of individuals with tetralogy of Fallot.

The possible anatomic variations in each organ and its arterial and venous supply must be known by physicians, such as surgeons or radiologists, in order to correctly identify those structures.

Unlike congenital anomalies, anatomic variations are considered normal and do not constitute a disorder.

The reason that SOS does not occur in all individuals may be related to anatomic variations in the internal jugular vein.

Some people have the artery of Percheron, which is a rare anatomic variation in which a single arterial trunk arises from the posterior cerebral artery to supply both thalami.

The structure is subject to an important amount of anatomic variation, and therefore a size classification is proposed by Pelizzo et al.

Volvulus can also arise as a rare complication in persons with redundant colon, a normal anatomic variation resulting in extra colonic loops.