Just as we never shake loose certain axioms of surgery we learned in fellowship (I can still hear my preceptors’ voices in my head during some procedures!), we sometimes find ourselves relying on tried-and-true tools we first encountered during our training. Although these instruments may not represent the most recent innovations, we should view their age as a feature rather than a bug, as their longevity testifies to their effectiveness and trustworthiness.
In my operating room (OR), one such instrument is the Tano Diamond Dusted Membrane Scraper (Bausch + Lomb; herein called the Tano). The Tano comes in retractable 23- and 25-gauge options and nonretractable 20-, 23-, 25-, and 27-gauge options. This instrument, first introduced to me in surgical fellowship, remains a go-to tool in my armamentarium.
Some younger surgeons might think of the Tano as an instrument of yore: something surgeons used in a past era but not something suitable for a modern OR. In my experience, this is not the case. The Tano remains a reliable tool for experienced and novice surgeons alike. Of course, it must be used in the proper context to be valuable in a surgeon’s hands. To that end, let’s explore when and how not to use the Tano as well as when and how to use it.
Troubleshooting the Tano
Some surgeons have reported difficulty passing the Tano through a trocar; others have observed that the instrument bends if too much force is applied when attempting a pass. If the Tano feels like it is stuck inside the trocar or is failing to fully penetrate, I have found that performing a series of small passes through the trocar in a jimmying motion eliminates adhesion or resistance.
If you find that the Tano is not a fit in your hands, the Finesse Flex Loop (Alcon) could be a useful alternative. The Finesse Flex Loop allows surgeons to extend or retract a loop at the end of the instrument, with flexibility increasing the further the loop is extended. Personally, I do not use the Finesse Flex Loop’s variation in flexibility in my surgical approaches; for this reason, I prefer the Tano’s constant flexibility.
Appropriate applications of the Tano
My experience and comfort with the Tano underpin my instinct to reach for it in specific cases, and its tendency to produce repeatable and predictable results reinforces my belief that this instrument is worth keeping on my tray. I turn to the Tano in cases of internal limiting membrane (ILM) or epiretinal membrane (ERM) peels in the context of retinal detachment (RD) secondary to macular hole (MH). It is often difficult to spot an ILM or ERM edge to grasp prior to peeling in these cases, which is where the Tano comes in handy.
To address this challenge, I first stain with TissueBlue (DORC/Zeiss). Then, using the Tano, I scrape outwardly from the center of the ILM toward, but not touching, the fovea, employing a spokes-on-a-wheel pattern with the Tano to create enough disruption to the membrane’s integrity such that a graspable rough edge might appear. After restaining, which is needed so that I may properly visualize the edge I created, I identify an edge large and sturdy enough to grasp, initiate peeling, and proceed with MH closure and RD repair. I use this same technique for membrane peels in the setting of macula-off RDs if the pinch-and-peel technique is not allowing me to find a flap to grab.
Remember, in these cases, the retina is mobile, and surgeons want reassurance that they are peeling only the ILM or ERM and not causing iatrogenic damage along the way (Figure 1). Approaching a membrane peel with a Tano as described above makes me confident that I am addressing the correct tissue, removing as much as possible, and not risking further damage.
My use of the Tano to create membrane flaps is not limited to cases of RD secondary to MH or cases of macula-off RD. I sometimes use the Tano to scrape a membrane in routine cases where a graspable membrane flap does not obviously present.
Inappropriate application of the Tano
I find that in cases that do not include the macula, the Tano offers little use. Take, for instance, rhegmatogenous RD (RRD) repair. My typical instrumentation lineup sufficiently addresses the anatomy in an RRD repair, and including the Tano to my instrument tray would only add clutter.
Some surgeons may find that using the Tano for membrane flap creation, as described previously, is less useful as they become more comfortable with pinch-and-peel approaches. This is very reasonable and a natural progression with time. Although we may reach for the Tano less as we become more experienced, it is still a helpful tool to have on hand for those difficult cases.
When surgeons should exercise experience-based judgment
There are many cases in which I consider the Tano a “sometimes” option. That is, depending on the circumstances, I might use the Tano to achieve a surgical goal.
Patients who need reoperation for chronic large MH often present without ILM due to prior extensive ILM peeling, which means that surgeons have no easily accessible autologous tissue with which to plug the MH or create an ILM flap. In this case, I could use the Tano to reduce tissue rigidity, restricting MH closure by addressing the area immediately around the MH, brushing from the outermost region toward the MH itself, and thereby loosening subretinal adhesions to facilitate MH closure (Figure 2). There are, of course, other tactics employed in the closure of large MHs. Surgeons should defer to their expertise and judgment on which approach works best for that particular patient.
This same approach that I use for peeling ILMs or ERMs in the context of MH-related RDs may be applied to diabetic membrane peeling or RD repair secondary to proliferative vitreoretinopathy. In these cases, a surgeon could brush the membrane with the Tano to see whether any distinction can be made between the layered tissues. The Tano can help make differentiation among tissue planes, helping to more safely perform surgery in these challenging cases. Conversely to using the Tano, surgeons might opt to use a cutter in these cases, and that is perfectly fine. In fact, I often use the cutter in these cases myself. Still, having the Tano available comes in handy when, in my estimation, an approach with the cutter is unsafe or ineffective.
Don’t rule out the Tano in your OR
Surgeons value optionality. Knowing that a possible solution to a surgical question sits on our instrument tray lets us operate with confidence. The Tano can be nice to have in your lineup of typical instruments and can increase your range of choices when encountering pesky membranes or challenging anatomic anomalies.
Priya Sharma Vakharia, MD
Retina Vitreous Associates of Florida, multiple locations
pvakharia@rvaf.com
Financial disclosures: honoraria (Bausch + Lomb, Gyroscope Therapeutics), consultant (Alimera Sciences Inc, Genentech), speaker (Genentech, Heidelberg Engineering).
