Eyeworld

EW RETINA 72 July 2015 by Maxine Lipner EyeWorld Senior Contributing Writer placebo in conjunction with diet, Dr. Wall believes this indicates that the weight loss alone was also some- what effective. Otherwise the effect would likely have been evident from the start rather than taking 6 to 8 weeks, he said. Two-pronged effect The overall goal of 6% weight loss by the end of 6 months was ulti- mately met. "We had this gradual improvement (with diet) from no improvement at month 1 to mild improvement at month 6," Dr. Wall said. Meanwhile, the acetazolamide group saw a lot of improvement at month 1, followed by some gradual improvement after that. Investiga- tors believe the initial improvement is mainly from the acetazolamide, while that seen after month 1 may small amount until the medication caused symptoms that interfered with activities of daily living, then we backed off on the dose," Dr. Wall said. "Our median dose was 2.5 grams a day while our maximum dose was 4 grams a day." Approxi- mately 40% of patients reached this maximum dosage. "The main thing we learned is that acetazolamide improves vision in these patients with mild visual loss treated with acetazolamide and diet," he said. "We also learned that patients got better with diet and placebo as well." However, there was about twice as much improvement with the acetazolamide and weight loss versus placebo with weight change, he said. Because it was a gradual im- provement for those receiving to make sure subjects had enough visual loss that we could show an effect if there was one." Those who met the entry criteria were randomized to receive placebo plus aim for a 6% weight loss with a lifestyle change on a low sodium diet or to get acetazolamide with the same weight loss goal. Investigators believed they couldn't forgo weight loss here since there is a lot of evidence that this helps people with the disease, Dr. Wall explained, adding that patients were followed for 6 months for the primary outcome analysis. Since the optimum dosage of acetazolamide was not known, investigators used the maximum amount tolerated up to 4 grams per day. "In our protocol, about twice a week we'd increase the dose by a Acetazolamide use together with weight loss helps restore vision P atients with mild idio- pathic intracranial hyper- tension enjoy about twice as much visual improve- ment when treated with acetazolamide in conjunction with weight loss as with weight loss alone, according to Michael Wall, MD, professor of neurology and ophthalmology, University of Iowa, Iowa City. With this condition, patients suffer from an array of symptoms such as headache, neck pain, back pain, pulse synchronous tinnitus, and visual loss, he noted. Close to two-thirds have episodes of transient visual loss. "This often occurs with standing or changing posture," Dr. Wall said. "It lasts from seconds to a maximum of about 1 minute." In addition, permanent visual loss can occur—this is akin to what happens in glaucoma with more damage oc- curring in the peripheral rather than the central field, Dr. Wall noted. "So patients don't notice it at first." New evidence base Investigators hoped to break new ground in studying idiopathic in- tracranial hypertension, which had been retrospectively reviewed prior to this. "We realized we need to better study this disease that causes a lot of visual loss," Dr. Wall said. "The treatment trial here was to give some evidence base to what we do— all we had before this were people's reports looking at retrospective chart reviews." Included in the prospective study were 165 idiopathic intracra- nial hypertension patients with mild visual loss, who met the modified Dandy criteria for the disease. These include common patient symptoms of raised pressure and optic disc swelling and sometimes double vision in addition to visual loss, all in conjunction with an otherwise normal neurologic exam and no medications known to cause intra- cranial hypertension in the mix. "Our main entry criteria was that we were studying patients with mild visual loss," he said. "We wanted Alleviating idiopathic intracranial hypertension Optic nerve swelling in an intracranial hypertension patient Source: Michael Wall, MD

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