The next time the world starts spinning, Patti will know exactly how to make it stop.  But two months ago, when the 50-year-old Ocean County resident woke up spinning with vertigo for the last time, she had no idea what to do.  “I felt like I was drunk,” she said. “I couldn’t stand up. I kept falling over.”   Fortunately for her, she had a friend who also came to my office for vertigo, who has also been asymptomatic since.  They, as well as many others, are better thanks to a simple technique that neurology experts have verified as the best way to treat benign paroxysmal positional vertigo — BPPV — a common cause of severe dizziness.  A series of gentle head and neck movements known as the canalith repositioning procedure is the fastest, easiest way to cure BPPV, according to a new guideline developed by the American Academy of Neurology.  Although only recently gaining awareness, I have been using this technique for decades to successfully treat vertigo.  About 3 million new patients a year in the United States are diagnosed with the problem characterized by dizziness, lightheadedness, imbalance and nausea that can last for days — or even months. Traditional treatments have ranged widely, from drastic measures such as sedatives to nerve surgery to nothing at all.  “Instead of telling patients to ‘learn to live with it’ or having them take drugs, we can perform a safe and quick treatment that is immediate and effective.  BPPV is caused when tiny calcium carbonate crystals called otoconia dislodge in the inner ear and land in the sensing tubes that detect motion and gravity. When sufferers move their heads, those otoconia cause severe sensations of spinning or whirling.  It can be overwhelming as those afflicted just assume that they are having a stroke from the severity of the dizziness.  The condition is typically caused by head injury in people younger than 50, although it is far more common in the elderly, as aging causes degeneration in the structures of the inner ear.  The canalith repositioning procedure works by moving the calcium crystals out of the sensing tubes and into another chamber of the inner ear, where they’re safely reabsorbed. The maneuver, which resolves vertigo in our office in better than 90 percent of our patients, is widely used, but only among doctors who know about it. The technique is not taught in medical schools and most general practice doctors may have heard only rumors of a quick, easy way to treat vertigo.  In the early years, the technique was ridiculed by colleagues for suggesting that such a simple treatment could have profound effects on vertigo. Our office now sees many referrals from local internists for the procedure.