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    <recommendedItem id="20100101_19_442"
                     title="Most Mountaineers Can Enjoy the View (CME/CE)"
                     score="0.01"
                     href="http://www.medpagetoday.com/Ophthalmology/GeneralOphthalmology/tb/18359?impressionId=1265782664574"
                     
      &lt;p&gt;Although the vistas from some of the world&apos;s highest peaks are literally &quot;eye-popping,&quot; most climbers don&apos;t have to worry about their high-altitude vision.&lt;/p&gt;
&lt;p&gt;Corneal thickness did swell significantly among mountaineers at elevations up to 6,300 meters (about 21,000 feet), but they had no loss in visual acuity, Martina Monika Bosch, MD, of University Hospital Zurich in Switzerland, and colleagues reported in the February &lt;em&gt;Archives of Ophthalmology&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;&quot;It seems that visual acuity in healthy corneas is not adversely affected despite the presence of edema at altitudes up to 6,300 meters,&quot; the researchers wrote.&lt;/p&gt;
&lt;p&gt;Yet they warned that altitudes above 8,000 meters, or 26,000 feet, &quot;may result in profuse edema leading to dangerous visual loss.&quot;&lt;/p&gt;
&lt;p&gt;Mt. Everest is just over 29,000 feet high.&lt;/p&gt;
&lt;p&gt;Research has shown that hypobaric atmospheric conditions are linked to acute mountain sickness, as well as to the more unusual cerebral edema.&lt;/p&gt;
&lt;p&gt;High altitudes have also been associated with decreases in visual acuity, as was the case for Dr. Beck Weathers, a Mount Everest climber who had lasik surgery prior to his climb and experienced severe vision loss before reaching the summit.&lt;/p&gt;
&lt;p&gt;So, to investigate the effects of very high altitudes on corneal thickness, the researchers conducted a study of 28 healthy mountaineers ages 26 to 62, who were on a medical research expedition to Mount Muztagh Ata in China, an elevation of 24,757 feet.&lt;/p&gt;
&lt;p&gt;The climbers were randomly assigned to two groups: one had a shorter time to acclimate to altitude conditions prior to reaching a camp at 21,736 feet.&lt;/p&gt;
&lt;p&gt;The researchers measured corneal thickness via ultrasound pachymetry.&lt;/p&gt;
&lt;p&gt;They found that corneal thickness increased in both groups at higher altitudes, with shorter acclimatization times leading to greater differences (&lt;em&gt;P&lt;/em&gt;=0.048). For this group, mean corneal thickness increased from 537 mcm to 572 mcm.&lt;/p&gt;
&lt;p&gt;Corneal thickness in the group that had more time to acclimate rose from 534 mcm to 563 mcm.&lt;/p&gt;
&lt;p&gt;Visual acuity didn&apos;t significantly decrease during the course of the expedition. However, the researchers warned that higher altitudes induce more endothelial pump function failure and may result in profuse edema, leading to vision loss.&lt;/p&gt;
&lt;p&gt;While the cause of corneal swelling in hypoxic conditions is still controversial, the researchers suggested that a higher concentration of lactate may reduce activity of the eye&apos;s endothelial pump function, resulting in corneal swelling.&lt;/p&gt;
&lt;p&gt;There were no differences in mountain sickness between the groups, but oxygen saturation during the expedition was significantly lower than at baseline in both.&lt;/p&gt;
&lt;p&gt;Changes in oxygen saturation paralleled those of corneal thickness, the researchers said, indicating that slower acclimatization resulted in less corneal edema.&lt;/p&gt;
&lt;p&gt;Also, climbers with more acute mountain sickness had thicker corneas, possibly due to their higher overall susceptibility to hypoxia.&lt;/p&gt;
&lt;p&gt;&quot;These findings further support our hypothesis that blood oxygen saturation becomes more important for the endothelial pump function when environmental oxygen pressure and, thus, tear film oxygen saturation, is reduced to a critical level,&quot; they wrote. &quot;Our results thus highlight the importance of aqueous humor oxygen delivery.&quot;&lt;/p&gt;
&lt;p&gt;The study was limited by the inability to measure corneal thickness daily due to adverse weather conditions.&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;The study was supported by grants from the Swiss National Research Science Foundation, the Swiss Society of Mountain Medicine, and Pfizer.&lt;/p&gt;&lt;p&gt;The researchers reported no conflicts of interest.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_354"
                     title="AMD Drugs Equally Effective (CME/CE)"
                     score="0.007"
                     href="http://www.medpagetoday.com/Ophthalmology/GeneralOphthalmology/tb/18238?impressionId=1265782664574"
                     
      Visual acuity showed similar improvements with two vascular endothelial growth factor inhibitors used to treat age-related macular degeneration (AMD), data from a retrospective study showed.&lt;br&gt;
&lt;br&gt;About a fourth of patients treated with bevacizumab (Avastin) or ranibizumab (Lucentis) had &amp;#8805;20/40 vision at 12 months.&lt;br&gt;
&lt;br&gt;The frequency of adverse events did not differ between treatment groups, but bevacizumab patients received fewer injections over the course of a year, investigators at Kaiser Permanente Southern California in Pasadena reported in the February issue of &lt;em&gt;Ophthalmology&lt;/em&gt;.&lt;br&gt;
&lt;br&gt;&quot;What this article principally does is that it reassures patients and ophthalmologists that bevacizumab appears to be just as effective as ranibizumab,&quot; said first author Donald Fong, MD. &quot;It provides more reassurance than changing practice.&quot;&lt;br&gt;
&lt;br&gt;The results likely will not end discussion about the relative safety and efficacy of the two drugs for treatment of AMD.&lt;p&gt;&lt;/p&gt;
&lt;p&gt;Ranibizumab was developed specifically for treatment of neovascular (wet) AMD, while bevacizumab was developed for oncology but is widely used off-label for treatment of AMD.&lt;/p&gt;
&lt;p&gt;Much of the debate over the drugs involves cost, as ranibizumab costs about $2,000 per injection compared with about $50 for bevacizumab.&lt;/p&gt;
&lt;p&gt;The two drugs are being compared in an NIH-sponsored multicenter clinical trial, but results are not expected before 2011.&lt;/p&gt;
&lt;p&gt;In an indirect comparison of the two drugs, Fong and co-authors retrospectively reviewed records of 452 patients treated for exudative AMD with bevacizumab or ranibizumab, both of which inhibit angiogenesis via vascular endothelial growth factor.&lt;/p&gt;
&lt;p&gt;The study population comprised 324 patients treated with bevacizumab and 128 treated with ranibizumab.&lt;/p&gt;
&lt;p&gt;The bevacizumab patients were younger (78 versus 82 on average), and 83% of the ranibizumab patients were 75 or older compared with 70% of the bevacizumab group.&lt;/p&gt;
&lt;p&gt;A higher proportion of bevacizumab patients had baseline visual acuity &amp;#8804;20/200 (40.1% versus 33.6%), but a similar proportion in each group had visual acuity &amp;lt;20/40 (86.4% versus 88.3%).&lt;/p&gt;
&lt;p&gt;The primary outcome of the analysis was visual acuity at 12 months. The authors reported that 22.9% of bevacizumab patients and 25.0% of ranibizumab patients attained visual acuity &amp;#8805;20/40 after a year of treatment.&lt;/p&gt;
&lt;p&gt;Additionally, 27.3% of bevacizumab patients and 20.2% of the ranibizumab group exhibited some degree of improvement at 12 months. Neither difference was statistically significant.&lt;/p&gt;
&lt;p&gt;Eight (2%) bevacizumab patients and four (3%) ranibizumab patients died before 12 months. Two patients in each group developed endophthalmitis.&lt;/p&gt;
&lt;p&gt;Bevacizumab patients received an average of 4.4 injections during 12 months, compared with 6.2 for the ranibizumab group. The authors speculated that the difference might reflect physicians&apos; belief that bevacizumab is a larger molecule with a longer intraocular half-life.&lt;/p&gt;
&lt;p&gt;In summarizing the results, the authors acknowledged the observational, nonrandomized nature of the study, as well as the lack of a standardized protocol for injecting the drugs.&lt;/p&gt;
&lt;p&gt;Moreover, some patients initially on bevacizumab switched to ranibizumab when the newer drug became available and that switch &quot;most likely accounted for some of the changes observed in the bevacizumab group.&quot;&lt;/p&gt;
&lt;p&gt;The authors also addressed differences between their findings and those from two Genentech-sponsored clinical trials.&lt;/p&gt;
&lt;p&gt;The trials showed that 94% of patients treated with ranibizumab did not have doubling of their visual angle versus 85% in the Kaiser chart review. The authors attributed the difference to the older age of their patients, the exclusion of patients with visual &amp;lt;20/320 in the Genentech studies, and the fewer ranibizumab injections (6.2 versus &amp;gt;11 in the Genentech studies).&lt;/p&gt;
&lt;p&gt;Despite the differences and limitations, the authors concluded that &quot;both treatments seem to be effective in stabilizing visual acuity loss.&quot;&lt;/p&gt;
&lt;p&gt;In a prepared statement, Genentech officials said they still believe ranibizumab &quot;is the most appropriate medicine for people with wet age-related macular degeneration because it was specifically designed, formally studied, manufactured for intraocular delivery, and is approved by the FDA.&lt;/p&gt;
&lt;p&gt;At the same time, Genentech does not interfere with doctors&apos; prescribing choices and believes that they should be able to prescribe the treatment they believe is most appropriate for their patients.&quot;&lt;/p&gt;
&lt;p&gt;In addition to limitations acknowledged by the authors, the statement also pointed out that the method for measuring visual acuity differed from the method used in most phase III clinical trials and that methods used to collect safety data differed from those typically used in prospective, randomized clinical trials.&lt;/p&gt;
&lt;p&gt;Genentech also questioned the lack of explanation for the higher proportion of patients who switched from bevacizumab to ranibizumab compared with ranibizumab to bevacizumab (23% versus 3%).&lt;/p&gt;
&lt;p&gt;A clinical spokesperson for the American Academy of Ophthalmology told &lt;em&gt;MedPage Today&lt;/em&gt; that the results of the Kaiser study tend to support ophthalmologists&apos; views about use of the two drugs to treat AMD.&lt;/p&gt;
&lt;p&gt;&quot;It looks like all the debate about the superiority or inferiority of one medicine over the other medicine is becoming essentially nullified,&quot; said Abdhish Bhavsar, MD, director of clinical research at the Retina Center of Minnesota in Minneapolis.&lt;/p&gt;
&lt;p&gt;&quot;I think that these medicines both do a good job at treating, and I don&apos;t think that distinction in clinical practice is relevant anymore.&quot;&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;The study was supported by the Southern California Permanente Medical Group.&lt;/p&gt;&lt;p&gt;Co-author Peter Custis disclosed a relationship with Med E Direct.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20090101_3_291"
                     title="Early Eye Exams Needed for Children Born Prematurely"
                     score="-0.005"
                     href="