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<recommendedContent xmlns="http://api.mspoke.com">
    <recommendedItem id="20100101_19_442"
                     title="Most Mountaineers Can Enjoy the View (CME/CE)"
                     score="0.015"
                     href="http://www.medpagetoday.com/Ophthalmology/GeneralOphthalmology/tb/18359?impressionId=1265759778563"
                     
      &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="0.011"
                     href="http://www.medpagetoday.com/Ophthalmology/GeneralOphthalmology/tb/18238?impressionId=1265759778563"
                     
      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_19_2536"
                     title="Gene Therapy Improves Vision in Leber&apos;s Amaurosis"
                     score="-0.005"
                     href="http://www.medpagetoday.com/Ophthalmology/GeneralOphthalmology/tb/15497?impressionId=1265759778563"
                     
      &lt;p&gt;Gene therapy for Leber&apos;s congenital amaurosis led to unexpected late improvement in vision, apparently by inducing development of a pseudofovea, investigators in an ongoing study reported.&lt;/p&gt;
&lt;p&gt;A year after treatment, one of three patients reported that, for the first time, she could read a numerical clock display on the dashboard of the family vehicle, according to a letter in the Aug. 13 issue of the &lt;em&gt;New England Journal of Medicine&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;Examination of the treated eye revealed a gradual shift in fixation of the patient&apos;s gaze from the untreated foveal area to the treated region of the retina.&lt;/p&gt;
&lt;p&gt;&quot;The change in fixation by the patient was driven by the treatment-created extrafoveal cone vision with better sensitivity and greater expanse than the untreated foveal region,&quot; Artur V. Cideciyan, PhD, of the University of Pennsylvania, and colleagues reported.&lt;/p&gt;
&lt;p&gt;&quot;These results raise the possibility that this gene-based therapy may further improve visual function in an unexpected and useful way in previously untreated congenital blindness,&quot; they added.&lt;/p&gt;
&lt;p&gt;Leber&apos;s congenital amaurosis is the first human genetic disease of the retina to show improved vision in response to treatment.&lt;/p&gt;
&lt;p&gt;Three patients with mutations in the gene encoding retinal pigment epithelium-specific 65-kD protein had improved vision within weeks of subretinal injection of a gene-containing vector into one eye (&lt;em&gt;N Engl J Med&lt;/em&gt; 2008; 358: 2231-39, 2240-48; &lt;em&gt;Hum Gene Ther &lt;/em&gt;2008; 19: 979-90).&lt;/p&gt;
&lt;p&gt;Examination of the patient who could read the dashboard clock revealed a visual acuity of 20/200, which did not differ from baseline or the one-year examination. Visual sensitivity also was unchanged.&lt;/p&gt;
&lt;p&gt;Prior to treatment, the patient had foveal fixation in both eyes, consistent with that of other patients with Leber&apos;s congenital amaurosis and similar visual acuity, the authors said.&lt;/p&gt;
&lt;p&gt;Fixation dwell time, quantified over a range of target luminances perceived by the patient, suggested a gradual emergence of visual gain over many months, causing progressively greater fixational use of the treated area of the retina.&lt;/p&gt;
&lt;p&gt;The gain was most evident at lower luminances, and by 12 months the patient could perceive the lowest luminance target (1.8 log&lt;sub&gt;10&lt;/sub&gt;).&lt;/p&gt;
&lt;p&gt;&quot;New perception was accompanied by a distinct shift in fixation into the treated superotemporal retina,&quot; the authors said.&lt;/p&gt;
&lt;p&gt;&quot;Foveal sensitivities in the two eyes were similar, but the superotemporal region of the treated eye, the &apos;pseudofovea,&apos; was remarkably different from the cone blindness in the comparable region of the control eye,&quot; they added.&lt;/p&gt;
&lt;p&gt;&lt;table cellspacing=&quot;0&quot; hspace=&quot;1&quot; style=&quot;border-style:solid; border-width:1px; border-color:#8dabbc; font-family:arial; font-size:12px; background-color:#DBE9F2; padding:5px 5px 5px 5px;&quot;&gt;
&lt;tr&gt;&lt;td&gt;Co-authors William Hauswirth, Barry J. Byrne, and Shalesh Kaushal disclosed relationships with Applied Genetics Technologies, and Hauswirth and co-author Samuel G. Jacobson are co-holders of patents related to development of methods to prevent or treat blindness.&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;/p&gt;

    </recommendedItem>
    <recommendedItem id="20090101_19_3398"
                     title="AAO: Gene Therapy Restores Partial Vision (CME/CE)"
                     score="-0.005"
                     href="http://www.medpagetoday.com/MeetingCoverage/AAO/tb/16603?impressionId=1265759778563"
                     
      &lt;p&gt;SAN FRANCISCO  --  Gene therapy to counteract retinal degeneration from a rare inherited sight disorder improved vision in all patients, including one child who recovered near normal light sensitivity.&lt;/p&gt;
&lt;p&gt;Although the 8-year-old boy was the clearest success story, all the children with Leber&apos;s congenital amaurosis treated in the study regained sufficient vision to walk unaided, Jean Bennett, MD, of the University of Pennsylvania in Philadelphia, and colleagues reported here at the American Academy of Ophthalmology meeting.&lt;/p&gt;
&lt;p&gt;Younger patients appeared to respond best to the treatment, which involves injecting the eye with genetic material &quot;piggybacked&quot; on a virus, the researchers wrote in a simultaneous release paper in &lt;em&gt;The Lancet&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;The trial provides hope for victims of one of the most severe forms of inherited retinal degeneration, a disorder that currently has no treatment.&lt;/p&gt;
&lt;p&gt;But co-author Katherine High, MD, of Children&apos;s Hospital of Philadelphia, cautioned against considering it a cure at this point. &quot;We don&apos;t know how long it will last,&quot; she said, although she noted that the effect has lasted at least 10 years in animals.&lt;/p&gt;
&lt;p&gt;Children born with a mutation in one of 13 genes that cause Leber&apos;s congenital amaurosis typically have severe vision deficits from birth that progress to total blindness by ages 30 to 50.&lt;/p&gt;
&lt;p&gt;The results, while in an early phase and based on few treated patients, hold great promise, according to the authors of a commentary accompanying the &lt;em&gt;Lancet&lt;/em&gt; paper.&lt;/p&gt;
&lt;p&gt;Not only were the treatment effects sustained after only a single injection, but the same strategy may be effective in slowing or stopping retinal degeneration from other genetic causes, such as retinitis pigmentosa, wrote Frans Cremers, PhD, and Rob Collin, PhD, both of Radboud University Nijmegen Medical Centre in Nijmegen, the Netherlands.&lt;/p&gt;
&lt;p&gt;&quot;As novel therapeutic strategies are being developed for each of the separate genetic defects, ascertaining and genotyping the corresponding patients will be the real challenge in the coming decade,&quot; they said, noting that even in the industrialized world less than 10% of patients know the genetic cause of their inherited blindness.&lt;/p&gt;
&lt;p&gt;Gene therapy has already been applied successfully in animal models for eight genetic causes of blindness, including one that affects a protein needed for activity of the retinal pigment epithelium (&lt;em&gt;RPE65&lt;/em&gt;)  --  the cause of about 6% of Leber&apos;s congenital amaurosis cases.&lt;/p&gt;
&lt;p&gt;Bennett&apos;s group took the next step in a Phase I, dose-escalation study at the Children&apos;s Hospital of Philadelphia.&lt;/p&gt;
&lt;p&gt;Working with 12 patients ages 8 to 44 with the&lt;em&gt; RPE65&lt;/em&gt;-associated disorder, the researchers injected the worst eye with one subretinal shot of a replication-deficient adeno-associated virus engineered to carry normal wildtype DNA for the patients&apos; damaged gene.&lt;/p&gt;
&lt;p&gt;Over the next two weeks, all the patients reported improved vision in the injected eye in dimly lit settings. None had serious adverse events from the procedure.&lt;/p&gt;
&lt;p&gt;Visual acuity improved after treatment without a clear-cut dose effect. A stable, sustained increase from baseline emerged in all three of the patients given a low dose of the vector, three of the six given a medium dose, and one of the three given a high dose. One patient had a decline in visual acuity.&lt;/p&gt;
&lt;p&gt;Age wasn&apos;t a significant factor in this subjective response to treatment.&lt;/p&gt;
&lt;p&gt;But for improvements in visual field, the amount of potentially salvageable retina was a predictor.&lt;/p&gt;
&lt;p&gt;Because the disease progressively destroys viable photoreceptors, the researchers said it may not have been a surprise that patients younger than 20 had larger visual field recoveries than older patients.&lt;/p&gt;
&lt;p&gt;White light sensitivity improved substantially for five of seven patients treated after the testing equipment became available, with benefits only in the treated eyes.&lt;/p&gt;
&lt;p&gt;The youngest patients gained several log units of sensitivity, the researchers noted.&lt;/p&gt;
&lt;p&gt;Another objective measure of vision improvement  --  pupillary response  --  improved in the injected eye of all 11 patients tested, whereas the untreated eye showed minimal constriction when exposed to light.&lt;/p&gt;
&lt;p&gt;Dark adapted response to dim light improved in the injected eyes, but not in the uninjected, up to two years later with at least a 2 log unit increase in every patient.&lt;/p&gt;
&lt;p&gt;The most notable improvement in pupillary-light-response sensitivity was in the youngest patient. The 8-year-old recovered nearly the same light sensitivity seen in a group of control patients who did not have vision problems.&lt;/p&gt;
&lt;p&gt;Final level of sensitivity correlated with age (&lt;em&gt;P&lt;/em&gt;=0.002) and baseline sensitivity (&lt;em&gt;P&lt;/em&gt;=0.09).&lt;/p&gt;
&lt;p&gt;Nystagmus also improved, suggesting patients would be able to fixate on an object better.&lt;/p&gt;
&lt;p&gt;For four children, these benefits translated into the ability to navigate an obstacle course on their own with fewer errors and greater speed.&lt;/p&gt;
&lt;p&gt;Six patients overall were reclassified as no longer legally blind after treatment.&lt;/p&gt;
&lt;p&gt;&quot;The visual recovery noted in the children confirms the hypothesis that efficacy will be improved if treatment is applied before retinal degeneration has progressed,&quot; Bennett&apos;s group concluded.&lt;/p&gt;
&lt;p&gt;Their long-term goal is to administer genetic therapy as soon as a child is diagnosed and thus rescue as much of the retina as possible, High said.&lt;/p&gt;
&lt;p&gt;Further follow-up is now needed to see whether this treatment alters the natural progression of retinal degeneration, the researchers noted.&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;Children&apos;s Hospital of Philadelphia was the main source of funding for the study with additional grants from Telethon, Regione Campania Convenzione, the Fund for Scientific Research, Fund for Research in Ophthalmology, National Center for Research Resources, and the European Union. It was also supported by the Foundation for Retinal Research and Associazione Italiana Amaurosi Congenita di Leber. One of the researchers was supported by the Fund for Scientific Research Flanders grant.&lt;/p&gt;&lt;p&gt;Bennett and a co-author reported being co-inventors on a pending patent for a method to treat or slow the development of blindness, but both waived any financial interest in this technology in 2002. Bennett reported conflicts of interest with Ceregene and Novartis.&lt;/p&gt;&lt;p&gt;Co-authors reported conflicts of interest with Tacere, Amsterdam Molecular Therapeutics, Genzyme, Arthrogen and being inventors on patents describing methods for adeno-associated virus vector manufacturing and methods for the detection and modulation of T cell responses to the capsid.&lt;/p&gt;&lt;p&gt;Cremers and Collin 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="20090101_2_692"
                     title="AAO: Look Beyond Visual Factors to Explain Patient Dissatisfaction with LASIK"
                     score="-0.005"
                     href="