We have a guest contributor this week. Dr. Phillip Griffin is an audiologist and vestibular specialist practicing in the High Point/ Greensboro, NC area. This entry will appeal to us vestibular geeks who sit around thinking about how the inner ear and brain work together. Lay readers will struggle with some of the terminology.
A case of PICA…without eating all that chalk
To a psychiatrist, “Pica” is a disorder of compulsively eating non-nutritive substances; things like chalk, glue, lip-balm, or even metal. While buying and eating chalk is probably less expensive than doing the same for tomatoes, it sure does make a gritty salsa. Bring your premium nachos! And your dental insurance.
Of course, to those interested in dizziness, the PICA syndrome is the most common brainstem stroke. Also know as lateral medullary syndrome or Wallenburg’s Syndrome, it typically affects vestibular nuclei, cerebellar peduncles (carrying information to the vestibulocerebellum), the cerebellum, and various other brainstem nuclei. Included in the list of possible symptoms are: 1) Vertigo, 2) Limb and trunk ataxia, 3) Horner’s syndrome, 4) Diminished pain and temperature sensation over ipsi face and contra body, 5) dysarthria 6) dysphagia, 7) dysphonia, and others. I’ll present a case of a patient with PICA syndrome with an interesting twist.
The patient is 75 year old female whose medical history is remarkable for hypertension, diabetes, hypercholesterolemia, heart disease with quadruple bypass, and MVA with multiple surgeries on lower extremities. She suffered a left PICA stroke 2 years ago secondary to left vertebral artery occlusion, confirmed by MRI and MRA. Her initial symptoms were imbalance with tendency to veer to the left and dysphagia. Over the course of 2 days, she developed left-sided facial numbness, and left arm and left tingling (interesting, we would’ve expected contra arm and leg findings), and dysarthria. According to MRI, the cerebellum itself appeared unaffected. Her multiple imaging studies also showed carotid narrowing due to atherosclerotic disease, and extensive chronic cerebral microvascular ischemic changes. Eventually, the patient went to therapy for gait and balance for many months and ultimately regained good function.
However, in recent months, (the patient is unsure of exact timing of onset), she began experiencing gradual onset “funny vision”, “underwater” feeling in head, worsened balance, and “eyes don’t focus” after a head turn. No positional complains. No vertiginous crisis lasting hours. She was referred to me by her PT and PCP for vestibular evaluation. The results were remarkable for:
- Absent right VEMP
- Right posterior canal BPPV
- Direction-fixed left beating head shaking nystagmus
- Multifactorial dysequilibrium
- Right worse than left hearing loss
- No caloric weakness
So, we have a patient with a previous left PICA stroke now presenting with a seemingly asymmetrical right cochleovestibulopathy of gradual onset. The findings seem to fit the pattern of a peripheral vestibulopathy, despite the lack of a classic vertiginous crisis and caloric weakness. The question I am putting up for debate is: Is it peripheral, central, or mixed? The patient has enough vascular compromise to damage the peripheral and central blood supply. Is this a case of a gradual peripheral weakening that would normally be compensated for, but wasn’t due the patient’s chronic microvascular central changes, interfering with central compensation process? Central vestibulopathy with a peripheral twist? Or some other explanation? What do you think?
References:
Goebel, Joel. Practical Management of the Dizzy Patient.Philadelphia: Lippincott Williams and Wilkins, 2001. Print.
Jacobson, Gary and Neil Shepard. Balance Function Assessment and Management.San Diego: Plural Publishing, 2008. Print.
Hain, Timothy. PICA (posterior cerebellar artery syndrome). Dizziness-and-balance.com. Ed. Timothy Hain, 2010. Accessed July 10th 2011 https://www.dizziness-and-balance.com/disorders/central/strokes/pica.html
