Glaucoma Therapy Algorithms

SINGLE TRACK (“STANDARD THINKING”) ALGORITHM

MULTI TRACK (“STANDARD THINKING”) ALGORITHM

The glaucoma treatment pathway

In using the stepwise but flexible approach depicted in Figure 1 (“Multi-Track” algorithm), I always try to control IOP with the least number of medications, which may mean also offering SLT in some cases. The target IOP is important, but it depends on the many variables affecting the magnitude and rate of glaucoma progression. When drops (with or without SLT) are not enough, particularly if a patient requires more than two medications, ab-interno canaloplasty is the procedure that most closely adheres to the “MIGS principles.” Stenting and/or cutting would subsequently find their place within the algorithm, followed by more invasive bleb-forming procedures.

This diagrammatical treatment algorithm incorporates the many secondary features MIGS has brought to glaucoma surgery. Canaloplasty is not always preferable, namely, when the TM is already fibrotic, when the surgeon expects complicated cataract surgery, or when the glaucoma type is not right. Other factors in selecting a particular MIGS relate to risk analysis and disease magnitude and progression; in some cases, possibly pushing for stronger and consequently more invasive procedures earlier. On the other hand, there are exceptions in favour of canaloplasty—in pseudophakic patients with early glaucoma, where the evidence for microstents is not very strong, ab-interno canaloplasty would be my current first choice.

Conclusion

Every MIGS has its place in the glaucoma paradigm, and its true value is enabling the surgeon to customise the procedure to each patient. To realise the true benefits of each MIGS device, surgeons must carefully consider the preoperative and postoperative characteristics, review the published evidence, and engage in open and ongoing dialogue with their peers to determine patient selection criteria, procedure pearls, protocol suggestions, and best practice.

I also believe greater MIGS awareness among cataract surgeons would greatly help in the interventional management of ocular hypertension and early glaucoma. Coupling some MIGS procedures, such as ab-interno canaloplasty, more often when these patients undergo cataract removal could be an important step in preventing glaucoma development or progression—and may delay or avoid more invasive procedures.

For citation notes, see page 46.