RE:FDA/TOS Further to my previous post, I will try to clarify your good questions.
The FDA has "asked for specific testing to be documented pertaining to what they describe as “challenge features” of the identified devices” involving "testing the integrity of the adhesive seal found at and under the distal endcap of the duodenoscope after sterilization processing”, particularly "for devices that have previously been processed with less robust high level disinfections processes".
TSO3 has already submitted data and documentation that they can sterilize these duodenoscopes, including the distal cap area, for new and pristine appearing scopes, (and they already have approval for this in Canada and the EU). The FDA has not found this data unsatisfactory at all and they have certainly not rejected it, giving labelling for what was submitted. But, the FDA wants further unexpected data in light of their newer insight into some of the causes of the scope contamination issue that they perceive as “challenge features” of some scopes at the end cap area. Repeated cycles of these scopes in the VP4 has not ever caused a positive ‘air leak test’, but the FDA wants to understand using a new testing protocol that involves taking the distal tip adhesive out and disassembling the tip to know what number of repeated cycles can damage to the adhesive occur from sterilization for new and for used (and already partially damaged from use scopes that were treated previously with HLD protocols but remain clinically intact on inspection and on the ‘air leak test’). This will actually probably involve taking these tips apart physically following X repeated cycles to measure damage and see if at any point or number of cycles their can be damage that is not visible to inspection or not detected on an ‘air leak test’ that might indicate sufficient degradation that would render a scope not sterilizable and needing servicing. Prior to further testing, these tested scopes presumably will then have to be sent 1) back to Olympus where they will be re-glued with Olympus’s adhesive (which may apparently not be as resilient to some liquid disinfectants as one would want, especially not to peracetic acid used in the Steris 1E and other washers), and 2) back to third party service repair companies who, in working with TSO3, I understand, appear to have developed more resilient and robust adhesives.
I believe this data just described is the new unanticipated data requested when they say they want results of "testing the integrity of the adhesive seal found at and under the distal endcap of the duodenoscope after sterilization processing". They are almost really asking for IFU parameters.
Just FYI, no one will ever submit data for a scope that fails the 'air leak test' or that can be shown to be leaking, as this scope should be returned immediately to the manufacturer, or a third party, for repair. But, having identified, as the FDA has, that there is an issue of degradation of the adhesives around this tip with HLD systems, using corrosive disinfectants like paracetic acid, for scopes that still pass the ‘air leak test’, the FDA wants to know that the VP4 can still sterilize these tips in the worse case scenario with data showing at what point repeated cycles can be confirmed to show adhesive failure (following actually disassembling the tip) (for new scopes treated only with H2O2/Ozone and ones already damaged by HDL reprocessing) such that a scope might potetially be found not to be sterilizable without servicing and repair of the adhesive (with a standard adhesive or with a newer more resilient adhesive).
Because HLD systems do not sterilize and are not expected to be adequate protocols for the new upcoming standards of sterilization of scopes that AAMI and FDA are and will be mandating, HDL systems are not held to this higher standard of proving this extreme degree of sterilization robustness that the FDA wants from the VP4. This again simply puts the VP4 in a class all its own.
TSO3 will submit data for the most difficult Olympus Q180V first, and follow with data for other duodenoscopes. And, hopefully, the time frame will be far shorter than the maximum allowed for a reply by the FDA. There should be little FDA concern regarding the new Pentax scope with the disposable sterilizable end cap as it will be the easiest to sterilize, because the cap will be removed for cleaning and sterilization following each use. (Well done Pentax!)