Posterior capsule (pc) tear is a potential consequence of cataract extraction by predisposition to pc tear or zonular dehiscence can be influenced by many factors including, but not limited to, congenital posterior lenticonus, posterior sub capsular (psc) cataract, poor visibility secondary to patients comorbidity [ie.Dense arcus, pterygium, band keratopathy, corneal scars, interstitial keratitis], poor microscope illumination [red reflex], ergonomic obstacles, limited intraocular working space, abnormally long or short axial lengths, pseudoexfoliation, zonular laxity, poor dilation, intraoperative floppy iris syndrome (ifis), dense cataracts, asteroid hyalosis, or inadvertent patient movement.The conditions that increase the risk of pc tear during phacoemulsification include ergonomic obstacles, limited intraocular working space, poor visualization, increased nuclear size and density, weakened zonule, a radial tear in the capsulorhexis, and an inability to rotate the nucleus or epinucleus.These conditions may arise either because of the ocular anatomy, or because of surgical technique.There is no evidence contained within the reported information at this time that indicates that the design or performance of the system had any effect on the integrity of the posterior capsule.The vision system operator¿s manual includes a warning: ensure that appropriate system parameters and system settings are selected prior to starting the procedure.Adjusting aspiration rates or vacuum limits above the preset values, or lowering the intraocular pressure (iop) or iv pole below the preset values, may cause chamber shallowing or collapse which may result in patient injury.When filling handpiece test chamber, if stream of fluid is weak or absent, good fluidics response will be jeopardized.Good clinical practice dictates the testing for adequate irrigation and aspiration flow prior to entering the eye.The company service representative examined the system and was able to replicate the reported sm [pump speed failure] displaying.The fluidics module and the fluidics printed circuit board (pcb) were replaced to address the reported event of sm.The system was then tested and met all product specifications.The system manufacturing device history record (dhr) was reviewed.Based on qa assessment, the product met specifications at the time of release.The fluidics module and the fluidics printed circuit board (pcb) was received and a visual assessment of the returned fluidics printed circuit board (pcb) found no visual nonconformities.The sample was installed into a calibrated vision system, where it was found to meet specifications.The fluidics module was received and tested, where it was found to have a worn o-ring, which would have caused the sm [pump speed failure].Unrelated to the reported event, the sample was also found to have another type of worn o-ring.After replacing both o-rings, the fluidics module was found to meet specifications.However, the reported event of the system being involved in a procedure in which the patient received tears in their anterior chamber was unable to be confirmed.The root cause of the reported event of sm displaying can be attributed to the worn o-ring.The manufacturer internal reference number is: (b)(4).
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