Benefits of SubCyclo Laser Therapy Guided by High-frequency Ultrasound Biomicroscopy in Patients With Refractory Glaucoma

The effect of cumulative energy in repeated subliminal transscleral cyclophotocoagulation: a retrospective study

BACKGROUND

The long-term safety and efficacy of repeated applications of subliminal transscleral cyclophotocoagulation (SL-TSCPC) with a focus on cumulative energy was evaluated in glaucoma patients.

METHODS

In this retrospective, multicentric study the data of a total of 82 eyes with various causes of glaucoma that were treated with a single or multiple applications of SL-TSCPC were collected. Treatments were performed under general or local anesthesia with an 810 nm diode laser. Power was 2000 mW; duty cycle, 31.3%; total treatment duration, 80-320 s; equaling a total energy of 50-200 J per treatment session. Fifty-five eyes (55 patients) presented for all follow-ups, and these eyes were selected for further statistical analysis. The mean age was 60.0 ± 17.1 years, and 22 (40%) of the patients were female. Intraocular pressure (IOP) and dependence on further glaucoma medication were evaluated at 12 months following the initial treatment.

RESULTS

Eyes underwent 1 or 2 consecutive SL-TSCPC treatments. Median (min-max) baseline IOP of 34 (13-69) decreased to 21.5 (7-61), 22 (8-68), 20 (9-68), and 19.5 (3-60) mmHg at the 1, 3, 6, and 12-month postoperative timepoints respectively. The mean (± SD) IOP decrease at 12 months was 26 ± 27%, 39 ± 32%, and 49 ± 33% in the low (below 120 J, n = 18), medium (120-200 J, n = 24), and high (above 200 J, n = 13) cumulative energy groups respectively. At the 12-month timepoint, oral carbonic anhydrase use was discontinued in ¾ of the cases.

CONCLUSIONS

It was found that the repeated application of SL-TSCPC safely and efficiently decreases IOP in a Caucasian population with heterogenous causes of glaucoma, eyes with silicone oil responded to a greater extent. Inclusion of cumulative energy scales may contribute to better addressing repeated procedures in a standardized fashion.

Angle-closure glaucoma secondary to ciliary body cysts treated with subliminal transscleral cyclophotocoagulation. Report of a case

Angle-closure glaucoma secondary to ciliary body cysts is a rare condition. Different pharmacological and surgical treatment modalities have been described. Among these, subliminal transscleral cyclophotocoagulation is a promising alternative due to fewer ocular complications and the same intraocular pressure reducing efficacy. The case is presented of a 33-year-old woman with a 6-year history of uncontrolled ocular hypertension, and a one-month history of glaucoma, treated with multiple drugs and surgical interventions, with persistent elevated intraocular pressure. She came to the clinic due to eye pain and photophobia of the right eye of 3 days onset prior to her visit. An ultrasound biomicroscopy was performed, finding cysts in the ciliary body. It was then decided to perform subliminal transscleral cyclophotocoagulation, achieving a reduction in intraocular pressure, which was maintained after three months of follow-up.

An update on continuous-wave cyclophotocoagulation (CW-CPC) and micropulse transscleral laser treatment (MP-TLT) for adult and paediatric refractory glaucoma

PURPOSE

Continuous-wave cyclophotocoagulation (CW-CPC) is often preferred to medical and surgical treatments for managing refractory glaucoma. This review summarizes diode CW-CPC indications, history, histopathology, methods, efficacy and safety. It also provides an overview of the latest data available on micropulse transscleral laser treatment (MP-TLT) that uses repetitive micropulses of diode laser energy in an off-and-on cyclical fashion.

METHODS

A literature review was conducted on transscleral CW-CPC (CW-TSCPC), endoscopic CPC (ECP) and MP-TLT. Relevant series of adult and paediatric patients were included for assessing the procedures.

RESULTS

Regarding CW-TCPC, highly variable success rates are reported in the literature, depending on the definition of success, type of underlying glaucoma, energy settings, follow-up duration and retreatment rates. CW-CPC often needs to be repeated, especially in paediatric patients. CW-CPC exposes to risks of inflammation and chronic ocular hypotony or phthisis with irreversible visual loss. CW-TSCPC has mainly been used in very severe forms of glaucoma, in painful eyes with limited visual potential or after filtering surgery failure. Published data on ECP are more limited but overall good success rates have been reported. Through the direct visualization of the targeted ciliary body in anatomically abnormal eyes, ECP is the preferred surgical procedure in paediatric refractory glaucoma. Complication rates are relatively low after ECP; however, large studies with long-term follow-up are needed. ECP may be used in difficult, refractory cases, but it is often used earlier when combined with cataract surgery. Despite limited data on the exact mechanism of action of MP-TLT and a lack of standardization of laser settings, the first data from heterogeneous case series shows that it has a similar efficacy and a better safety profile compared to CW-TSCPC in the medium term.

CONCLUSION

Although they may lead to sight-threatening complications, both CW-TSCPC and ECP seem effective. ECP appears to be superior to CW-TSCPC in paediatric refractory glaucoma. Unlike ECP combined with cataract surgery, evidence supporting a wider use of CW-TSCPC and MP-TLT in earlier stages of neuropathy is lacking. While it now appears that the safety profile of MP-TLT is superior to that of CW-CPC, robust prospective comparative studies including homogeneous and well-defined cohorts of patients are still needed to confirm an at least comparable efficacy in the long term.

Angle-closure glaucoma secondary to ciliary body cysts treated with subliminal transscleral cyclophotocoagulation. Report of a case

Angle-closure glaucoma secondary to ciliary body cysts is a rare condition. Different pharmacological and surgical treatment modalities have been described. Among these, subliminal transscleral cyclophotocoagulation is a promising alternative due to fewer ocular complications and the same intraocular pressure reducing efficacy. The case is presented of a 33-year-old woman with a 6-year history of uncontrolled ocular hypertension, and a one-month history of glaucoma, treated with multiple drugs and surgical interventions, with persistent elevated intraocular pressure. She came to the clinic due to eye pain and photophobia of the right eye of 3 days onset prior to her visit. An ultrasound biomicroscopy was performed, finding cysts in the ciliary body. It was then decided to perform subliminal transscleral cyclophotocoagulation, achieving a reduction in intraocular pressure, which was maintained after three months of follow-up.

Comparative Effectiveness and Tolerance of Subliminal Subthreshold Transscleral Cyclophotocoagulation With a Duty Factor of 25% Versus 31.3% for Advanced Glaucoma

PRéCIS:: Subliminal subthreshold transscleral cyclophotocoagulation (SS-TSCPC) with duty cycles 25% and 31.3% seems to be an effective approach to reduce intraocular pressure (IOP) in glaucoma that is refractory to medical management.

OBJECTIVE

The objective of this study was to compare the effectiveness and the tolerance of SS-TSCPC with a duty cycle of 25% versus 31.3% with Supra 810 nm Subliminal Quantel Medical laser stimulation for advanced glaucoma.

MATERIALS AND METHODS

This was a retrospective, single-center, comparative case series of patients treated by SS-TSCPC between January 2017 and July 2017. The diagnostic and inclusion criteria were patients with advanced and refractory glaucoma, defined as IOP >21 mm Hg on maximal tolerated medical therapy with or without previous glaucoma surgical procedures, a minimum follow-up of 12 months, and patients who refused or were poor candidates for additional filtering surgery or implantation of glaucoma drainage devices. The primary endpoint was surgical success defined as an IOP of 6 to 21 mm Hg or a reduction of IOP by 20% from baseline without an increase in glaucoma medication from baseline. The secondary endpoints were the mean IOP and best visual corrected acuity best-corrected visual acuity at 12 months after surgery, retreatment outcomes, glaucoma medications, and complications such as inflammation, uveitis, cataract, mydriasis, and phthisis.

RESULTS

Forty eyes of 32 patients were included: 20 eyes were subjected to SS-TSCPC with 31.3% duty cycle and 20 eyes with a 25% duty cycle. The surgical success of the TSCPC 12 months after the first procedure was better in the 31.3% duty cycle group (83.5%) than in the 25% duty cycle group (65%). The most common complications were inflammation (50%, 1 mo after surgery) and IOP spikes (increase in IOP of >25% from baseline within 1 mo of laser) in both groups. Inflammation was higher in the 31.3% duty cycle group.

CONCLUSIONS

SS-TSCPC at 31.3% and 25% duty cycle seems to be an effective approach to reduce IOP in glaucoma that is refractory to medical management. SS-TSCPC at 31.3% duty cycle is more effective than the 25% duty cycle SS-TSCPC. However, the 31.3% duty cycle SS-TSCPC induces more inflammation than the 25% duty cycle SS-TSCPC. Each procedure should be considered on a case by case basis.