This is going to be a short and sweet TidBit Tuesday this week. I have been seeing some very unique head tilts and head turns over the past few weeks and thought that it might be fun to talk about these two neurologic findings.

First, let's differentiate between a head tilt and a head turn.
A head tilt is diagnosed when the orbits (eye sockets) are NOT parallel to the ground. When you look at the dog from the front, and draw a line between the orbits, that line should NOT be parallel to the ground for a head tilt. In contrast, a head turn is diagnosed when the head is deviated one direction, but the orbits remain parallel to the ground. Many dogs with a head tilt or turn will circle and most (not all) will circle the direction of their tilt or turn. Certainly, those with a head turn are expected to circle the same direction but animals with a head tilt have a little more variation.

What do we do with this information?
Both a head tilt and a head turn can help you localize the lesion. Animals with a head turn ONLY have evidence of a forebrain (telencephalon/diencephalon or cerebrum/thalamus) lesion. That means you're talking about something that might progress to seizures, mentation changes and/or blindness. If an animal has a head tilt *most* of the time this indicates a vestibular lesion. The vestibular lesion may be brainstem, cerebellar or peripheral in origin. A head tilt is NOT a localizing entity within vestibular disease. These animals may have, or progress to, nystagmus, nausea, positional strabismus, and vestibular ataxia. Other gait deficits such as hemiparesis, or hypermetria, could happen if the lesion is brainstem or cerebellar, respectively. On rare occasions, the head tilt can indicate a lesion in the forebrain as well. These are typically thalamic and come with head turns, and maybe even neck turns. They're very rare so don't fret if you forget that part of the head tilt story.

What do I do next if my patient has a head tilt or head turn?
With a head tilt, you'll want to further localize the lesion to peripheral neuropathy, brainstem or cerebellar localization so that you can build a suitable differential diagnoses list. Please see a prior TidBit for neuroanatomic lesion localization for vestibular disease. For patients with a head turn, you're pretty focused on the forebrain so you can go ahead and build your differential diagnoses list based on the history and signalment. Not sure what that list may be? Reach out! I'm here if you need to email about a case or schedule a consultation.

Short and sweet it was! I hope you found this TidBit useful today. Enjoy the rest of your week!