Diagnostic dilemma: A man's brain started bleeding after a dentist appointment

The patient: A man in his late 60s who lived in Australia

The symptoms: The man felt dizzy, began vomiting, and experienced warped vision in which everything appeared to be tilted 90 degrees counterclockwise.

What happened next: At the emergency department, doctors determined that the man had high blood pressure. His eyes flickered to the left, and when he walked, he would fall to the right. Scans revealed bleeding in the lower-left half of his brain.

The diagnosis: The man had an intracerebral hemorrhage (ICH), a type of hemorrhagic stroke in which a blood vessel ruptures in the brain.

The treatment: The immediate treatment for ICH involves stopping the bleeding, removing any blood clots and relieving pressure on the brain. After receiving care in the emergency department, the man was discharged and prescribed blood-pressure medication. Three months later, he had regained normal vision and his gait was steadier. He was then put on a long-term course of aspirin to improve blood flow in his brain and prevent further strokes.

What makes the case unique: The play-by-play of the man's stroke may not seem unusual, until you learn what likely triggered the event. The patient's symptoms emerged just 30 minutes after he'd had two teeth extracted at a dentist appointment. Previously, there had been a handful of cases in which people experienced ICH after their blood pressure jumped during a dental procedure, due to pain or stress — and that's what doctors suspect happened here.

The man's case was complicated by another factor: Six weeks before his dental visit, he'd been evaluated for signs of Parkinson's disease. At that time, brain scans revealed signs of low blood flow in his brain that was damaging the wiring between his brain cells.

This condition, called white matter disease, can be driven by genetics. So, while the man was being treated, his medical team also gathered a sample of his DNA to analyze. They found a mutation that's known to thicken the walls of blood vessels, narrowing them so that less blood reaches the brain. This results in CADASIL, a rare condition that affects about 2 in 100,000 people.

Sometimes, ICH may be a complication of CADASIL, some research suggests. This, combined with the blood-pressure spike from the tooth extraction, might explain why the man had a stroke.

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