Abstract
Background Glaucoma is one of the most common causes of blindness worldwide. The only evidence-based
treatment to slow down the progression of glaucoma is the reduction of intraocular
pressure (IOP) using local medication or through surgery. During the last years, a
large number of microinvasive glaucoma surgery techniques (MIGS) has been developed,
in order to reduce the IOP in glaucoma patients safely and effectively. Until now,
efficacy of MIGS has been assessed mainly according to the postoperative IOP and the
number of medications used. Results from long-term studies are rare or not available
in the majority of the cases. In order to better evaluate the functionality of MIGS,
a new examination method has been developed with the help of a new oculopressor device.
In this study the efficacy of different MIGS techniques will be examined using the
new oculopressor.
Material/Methods At first, glaucoma patients that had previously received a MIGS surgery (iStent inject,
XEN Stent, ELT) were examined with the new oculopression test. Their results were
compared with those of non-operated patients and healthy individuals. Overall, 38
healthy subjects (group 1), 10 non-operated patients (group 2), 19 patients after
iStent inject implantation (group 3), 14 patients after XEN Stent implantation (group
4) and 5 patients after ELT (group 5) were examined. The new examination measures
the IOP-reduction that occurs after oculopression and can be seen as an indirect measurement
of the outflow facility of the eye.
Results The IOP-reduction after oculopression differed among the study groups. Non-operated
patients showed a significantly lower IOP-reduction compared to healthy individuals.
Patients after iStent inject and XEN stent implantation showed a larger reduction
of IOP after oculopression in relation to non-operated patients and their results
approximated those of healthy individuals. These patients needed fewer medications
postoperatively in relation to non-operated patients. Patients after ELT showed postoperatively
a smaller reduction of IOP after oculopression compared to iStent inject and XEN stent
patients.
Conclusion MIGS can increase the outflow facility of the eye in patients with glaucoma. Though
ELT had the lowest impact on the aqueous outflow among the studied procedures in this
study. The new test can help in the evaluation of current and further development
of new MIGS in the future.
Key words
glaucoma - MIGS - oculopression - outflow facility - microinvasive glaucoma surgery
