Glaucoma surgeons are continually seeking innovations that deliver long-term intraocular pressure (IOP) control while minimizing complications and offering flexibility across diverse patient populations. Building on the Ahmed ClearPath® platform, New World Medical has introduced the Ahmed ClearPath® ST (ACP ST), a smaller-lumen tube featuring all-inclusive packaging that includes a pre-threaded 6-0 Prolene ripcord suture and a 25-gauge needle for scleral tunneling.
To better understand its impact in practice, we spoke with two glaucoma specialists, Dr. Andrés Gerhard of Hospital Dr. Sótero del Río, Chile, and Dr. Craig Chaya, Clinical Associate Professor at John A. Moran Eye Center, University of Utah, who share how ACP ST has influenced their surgical techniques, patient selection, and post-operative strategies.
First Impressions of the Ahmed ClearPath® ST
Dr. Gerhard: I began using ACP ST five months ago, and it has quickly become my preferred option. The procedure itself is similar to other glaucoma drainage implants, but with ACP ST I often see immediate IOP control with fewer hypotony-related concerns.
Dr. Chaya: We’ve had early access to ACP ST for six months. What stands out to me is the flexibility it offers for tube placement, especially in eyes with smaller anterior chambers or when positioning the tube in the sulcus, where space is limited.
Ligation or Non-Ligation?
Dr. Gerhard: Since adopting smaller tubes, I have moved away from ligation entirely. I now perform non-ligated procedures in all cases, which provides immediate pressure control. Avoiding a waiting period for IOP stabilization has been a major benefit.
Dr. Chaya: I strongly favor ligating the tube so there is no flow to the plate for the first six to seven weeks. When the ligature dissolves, I haven’t observed significant hypotony. I also use a ripcord in all cases, whether with ACP or ACP ST, as it provides early control if needed and may help reduce risk when the ligature opens.
Ripcord Removal: Timing and Technique
Dr. Gerhard: I leave the ripcord at the limbus in a small incision and typically remove it around three months post-op. If the pressure remains low, I may leave it in place without issue. Occasionally, I’ll remove it earlier, but I generally wait at least three to six weeks.
Dr. Chaya: I rarely remove the ripcord unless absolutely necessary. After the ligature dissolves at six to seven weeks, I reassess IOP. If a hypertensive phase occurs or pressure remains high, I remove it at that point. In some cases, the ripcord stays under the conjunctiva long-term without problems.
Patient Selection
Dr. Gerhard: Previously, I selected between an Ahmed® Glaucoma Valve for rapid IOP reduction in advanced cases or a non-valved ligated tube for those who could tolerate higher pressures initially. With ACP ST, I now use it broadly across my patient base without ligation, allowing immediate IOP control in all cases.
Dr. Chaya: I typically consider tube shunts for patients with advanced glaucoma or failed prior surgeries, including MIGS or trabeculectomy. For patients needing rapid IOP reduction, I tend to lean toward valved devices. However, with ACP ST, I’m increasingly considering non-valved options even in higher-risk cases. While non-valved devices carry hypotony risk, valved devices may encapsulate and limit long-term control. In select cases, ACP ST offers a more balanced option.
Lessons Learned
Dr. Gerhard: One key step is observing flow through the tube during surgery. If flow is insufficient, adjusting the Prolene ripcord can restore it. This has become an important surgical pearl when using ACP ST.
Dr. Chaya: The smaller-caliber tube has influenced my surgical technique. Previously, I used a braided Vicryl wick plus fenestrations for larger tubes. With ACP ST, I now use a finer 9-0 Vicryl monofilament for the wick, which fits the smaller lumen and creates a more controlled capillary effect. I’ve found wicks can lower IOP more predictably than fenestrations.
Looking Ahead: The Role of ACP ST
Dr. Gerhard: ACP ST represents an important advancement. The smaller tube provides reliable long-term IOP control with fewer hypotony concerns. I expect smaller tubes to play a growing role in the future of glaucoma drainage surgery.
Dr. Chaya: Many of us advocated for smaller-caliber tubes, believing they could improve fluid dynamics when the tube opens. Having ACP ST available is exciting, and I anticipate future shunts will continue in this direction. Over time, this may also reduce complication like tube erosion.
Conclusion
With ACP ST, New World Medical continues to meet the evolving needs of glaucoma surgeons by combining reliable pressure control with greater surgical flexibility. As Dr. Gerhard and Dr. Chaya highlight, its smaller-caliber tube offers distinct advantages across both immediate and long-term management, whether used in ligated or non-ligated configurations. Despite differing surgical approaches, both surgeons agree: ACP ST expands patient selection and refines decision-making. More than just a new device, it marks a step toward safer, more tailored solutions in glaucoma care.
