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September 2012 Review continued from page 89 Overall, this study makes an im- portant attempt to use experimental animal models to investigate the mechanism behind IFIS. Caution must be used in extrapolating the results of animal studies to human patients. While this study does demonstrate some pharmacologic responses between pigmented and albino irides, additional experiments would help to further define the role of drug pigment interactions in the pathophysiology of IFIS. As men- tioned above, direct comparison between pigmented and albino irides in the chronic tamsulosin model with pharmacologic as well as anatomical analyses would be very instructive. Finally, it is noteworthy that no association between iris color and IFIS was found in a prior prospective clinical study,1 empiric evidence suggesting that brown-eyed patients are more sus- ceptible to α1 antagonist-induced IFIS than blue-eyed patients. A prospective study of individuals correlating iris color, administration of tamsulosin, and severity of IFIS may help to demonstrate the contri- bution of drug-melanin interactions in IFIS. Although difficult due to its rarity, patients or animals with uni- lateral congenital iris heterochromia might be the ideal subjects to test the hypothesis that darker pig- mented irides are more susceptible to IFIS by means of α1 antagonist- pigment interaction. We congratu- nor is there a body of late the authors for this important study that provides information to help us better understand the pathophysiology of IFIS. EW References 1. Chang DF, Braga-Mele R, Mamalis N, Masket S, Miller KM, Nichamin LD, Packard RB, Packer M; ASCRS Cataract Clinical Committee. ASCRS White Paper: clinical review of intraoperative floppy-iris syndrome. J Cataract Refract Surg. 2008;34(12):2153-62. 2. Chang DF, Campbell JR. Intraoperative floppy iris syndrome associated with tamsulosin. J Cataract Refract Surg. 2005;31(4):664-73. 3. Santaella RM, Destafeno JJ, Stinnett SS, Proia AD, Chang DF, Kim T. The effect of alpha1-adrenergic receptor antagonist tamsulosin (Flomax) on iris dilator smooth muscle anatomy. Ophthalmology. 2010;117(9):1743-9. 4. Prata TS, Palmiero PM, Angelilli A, Sbeity Z, De Moraes CG, Liebmann JM, Ritch R. Iris morphologic changes related to alpha(1)- adrenergic receptor antagonists implica- tions for intraoperative floppy iris syndrome. Ophthalmology. 2009;116(5):877-81. 5. Goseki T, Shimizu K, Ishikawa H, Nishimoto H, Uga S, Nemoto N, Patil PN. Possible mechanism of intraoperative floppy iris syndrome: a clinicopathological study. Br J Ophthalmology. 2008; 92(8):1156-8. Contact information Gedde: sgedde@med.miami.edu Prognosticating outcomes for otherwise normal infants who miss visual milestones W hen it comes to premature infants, concerns about vision can be serious. But what about otherwise normal infants with decreased visual responsiveness who are brought in for evaluation with poor fixation and tracking that cannot be linked to systemic or ocular conditions? A recent retrospective cohort study e-published ahead of print in the August issue of Graefes Archive for Clinical and Experimental Ophthalmology indicated that while there may be understandable parental worries, the future here is almost always bright. The recent study, conducted by Roua Azmeh, M.D., and Gregg T. Lueder, M.D., considered prognostic factors for visual outcomes in otherwise normal infants whose medical records had been flagged early on as being visually unresponsive. In the study, 32 children with no systemic problems associated with developmental delays or history of premature birth were identified. Six of these children were lost due to lack of follow-up. In the case of four others, despite early concerns, by the time of their initial evaluation, normal mile- stones had been attained. The remaining children had up to 11 years of follow-up with a mean of 2.94 years. Investigators determined that of these remaining 22 children, just one had ongoing visual issues, requiring surgery for strabismus. The others all went on to have normal visual and developmental outcomes. Investigators found that prognosis appears to be good for those with decreased visual responsiveness who presented for evaluation with no ocular structural abnormalities and clinical signs such as normal pupil response and a reaction to light, with no nystagmus. For infants with such prognostic factors, investi- gators concluded that normal development can be expected with no need for additional testing during the initial evaluation. In to day''s s ec onomic clima onomic climate ... I trust my business to ASOA. www.ASOA.org The Physician's PERSPECTIVE