The Efficacy and Safety of High-Frequency Deep Sclerotomy in Treatment of Chronic Open-Angle Glaucoma Patients

Abstract

Purpose Highlights the high-frequency deep sclerotomy as a competing ab interno surgery in open-angle glaucoma patients and evaluates the efficacy of high-frequency deep sclerotomy in lowering IOP of chronic open-angle glaucoma patients, in addition to the evaluation of the safety of the procedure on the corneal endothelium. Design A prospective study. It was performed in the Research Institute of Ophthalmology, Cairo. Participants 43 eyes were enrolled for the study. All eyes were diagnosed with chronic open-angle glaucoma. Methods The procedure was performed using the abee® glaucoma tip of Oertli phacoemulsification machine (OS3, Switzerland) and goniolens performing nasal six pockets penetrating 1 mm deep into the trabecular meshwork and Schlemm's canal. Patients were followed up regarding vision and intraocular pressure (IOP) for 9 months. Endothelial cell count and coefficient of variation were calculated using specular microscopy preoperatively and 9 months postoperatively. Results The mean preoperative IOP was 31.4 ± 4.71 mmHg (range: 22 to 42 mmHg). All patients were followed up for nine months. The mean IOP was 19.06 ± 1.907 mmHg (range: 15 to 26 mmHg) by the end of the study. The reduction across the follow-ups was statistically significant (P < 0.0001). The percentage of total success was 90.7% (39 eyes). Four eyes (9.3%) had IOP > 21 (failed) after surgery and continued on antiglaucoma therapy. Conclusion High-frequency deep sclerotomy is a safe and promising minimally invasive procedure which successfully achieves a lower IOP for chronic open-angle glaucoma patients, but not adequate for advanced glaucoma patients. This trial is registered with PACTR201910823824561.

Surgical peripheral iridotomy creation during intraocular surgery by intraocular diathermy probe—a novel technique

“…6 Recently, we have discovered that this instrument may also be used for the creation of surgical PIs, provided that the machine is set to "high frequency deep sclerotomy," a setting with a different waveform that is more suited for cutting dense tissue. 7,8 Because the device simultaneously cauterizes as it cuts, the risk for intraoperative hemorrhage is low. Further, the handpiece is intuitive to use and reusable, which may be a relevant consideration in many surgical settings.…”

High-Frequency Deep Sclerotomy, A Minimal Invasive Ab Interno Glaucoma Procedure Combined with Cataract Surgery: Physical Properties and Clinical Outcome

“…The aim of the new nomenclature was to describe the procedure more precisely. Regarding the procedure, there were no differences between STT ab interno and HFDS [17][18][19][20].…”

Minimally Invasive Glaucoma Surgery: A Review of the Literature

“…High-frequency deep sclerotomy (HFDS), originally known as sclerothalamotomy ab interno (STT ab interno), aims to reduce IOP by creating microincisions in the sclera using high-frequency electric current, thereby enhancing uveoscleral outflow [ 32 , 33 ]. The HFDS procedure involves the placement of a specialized diathermic probe (Oertli Instrumente) equipped with a high-frequency generator into the suprachoroidal space, creating multiple small incisions in the sclera.…”

“…Initial studies investigating the use of HFDS in glaucoma management have shown encouraging results, with significant reductions in IOP and a favorable safety profile [ 32 , 33 , 35 ]. In addition, HDFS can be combined with cataract surgery while avoiding the risk of implant-related complications and has a relatively short learning curve for surgeons already experienced in glaucoma surgery.…”