Lower energy levels adequate for effective transcleral diode laser cyclophotocoagulation in Asian eyes with refractory glaucoma

Long-Term Results of Transscleral Diode Laser Cyclophotocoagulation in Glaucoma: A Real-Life Study

PRCIS

Transscleral diode laser cyclophotocoagulation (TDLC) is effective and safe in a large population and different types of glaucoma but is least effective in the neovascular glaucoma (NVG) group.

OBJECTIVE

We aimed to investigate the clinical outcomes of TDLC in a large cohort of patients with different types of refractory glaucoma.

PATIENTS AND METHODS

Using patient charts, we retrospectively analyzed the success and complications of TDLC performed on eyes categorized into 6 groups: primary glaucoma (116 eyes), trauma (41 eyes), NVG (84 eyes), post-vitreoretinal surgery (post-VRS, 79 eyes), penetrating keratoplasty (47 eyes), and miscellaneous (40 eyes). Failure was defined as intraocular pressure (IOP) >22 mm Hg or <5 mm Hg, the need for further glaucoma surgery, and the loss of light perception during follow-up.

RESULTS

Overall, the mean follow-up time was 33.4 ± 17.4 months, the mean total energy delivered was 109.2 ± 56.5 J, and the mean IOP reduction rate was 41.8%. Total energy delivered and IOP reduction rates were similar between the groups (all P > 0.05). The probability of success at 36 months was 71.5%, 70.7%, 55.9%, 77.2%, 72.3%, and 72.5% in primary glaucoma, trauma, NVG, post-VRS, penetrating keratoplasty, and miscellaneous groups, respectively. The NVG group showed a significantly lower success rate ( P = 0.009) than the other groups. Significant complications consisted of phthisis bulbi in 1 eye (0.2%) in the NVG group and chronic hypotony in 7 eyes (1.7%) in the NVG (3 eyes), trauma (2 eyes), post-VRS (1 eye), and primary glaucoma (1 eye) groups.

CONCLUSIONS

Although TDLC was found to be a safe, effective method in the long term, it was least effective in eyes with NVG.

Efficacy of a novel low-cost torchlight transcorneal transillumination for diode laser transscleral cyclophotocoagulation in adult glaucoma

PURPOSE

To study the outcomes of diode laser transscleral cyclophotocoagulation (TSCPC) with trans-corneal transillumination using a novel low-cost torchlight method in refractory glaucoma.

METHODS AND ANALYSIS

This prospective interventional study included patients with refractory glaucoma who underwent TSCPC with trans-corneal transillumination (TSCPC-TI) using a novel low-cost torchlight method. Patients completing a minimum 6-month follow-up were analyzed. They were compared to a historical control group of patients who underwent TSCPC without transillumination (TSCPC-No TI) at 6-month follow-up period. We analyzed the mean laser energy delivered, post-laser intraocular pressure (IOP) reduction, number of antiglaucoma medications (AGM), the requirement of retreatment and complications of the procedure in both groups.

RESULTS

32 eyes of 29 patients comprised the TSCPC-TI group and were compared with 39 eyes of 37 patients in the TSCPC-No TI group. The TSCPC-TI group required lower energy than the TSCPC-No TI group (46.15 ± 22.8 Vs 80.65 ± 56.1 J p < 0.001). At 6-month follow-up, the TSCPC-TI group required lesser AGM for IOP control (2.33 ± 1.02 vs 3.02 ± 1.32 p = 0.01). There was a significantly reduced dependence of oral acetazolamide in the TSCPC-TI group at 6 months follow-up (15.6% vs 41% p = 0.03%). The success and response rates were 71.8% Vs 23.1%; p < 0.0001 and 87.5% Vs 51.2%; p = 0.001 significantly high in the TSCPC-TI group. The TSCPC-No TI group had a significantly high failure rate (12.5% Vs 48.2% p = 0.001). Hypotony (n = 1) and phthisis (n = 2) were noted TSCPC-No TI group.

CONCLUSIONS

TSCPC with transillumination with a low-cost torchlight resulted in a more efficient and effective cycloablation than TSCPC without transillumination.

Efficacy and safety of transscleral cyclophotocoagulation versus cyclocryotherapy in the treatment of intractable glaucoma: A systematic review and meta-analysis

To perform a meta-analysis to compare the efficacy and safety of diode laser transscleral cyclophotocoagulation (TSCPC) and cyclocryotherapy (CCT) in the treatment of intractable glaucoma. Systemic searches of the Ovid MEDLINE, EMBASE, and Cochrane Library databases yielded experimental and observational comparative studies. TSCPC and CCT efficacy and safety outcomes were compared. Subgroup analyses of participant ethnicity, preoperative intraocular pressure (IOP) level, and underlying causes of glaucoma were conducted. The pooled effects were computed using the random-effects model. The meta-analysis included nine studies totalling 668 eyes. There was no statistically significant difference between the TSCPC and CCT groups in the IOP reduction (IOPR%), decrease in antiglaucoma medications, the operative success rate with or without medications, or retreatment rate in the efficacy analysis. In the subgroup analysis, CCT had a better IOP-lowering effect among non-Asian participants and a non-inferior IOPR% to TSCPC among Asian participants. TSCPC and CCT were associated with similar rates of deterioration in visual acuity, postoperative visual analog scale, and other analysed postoperative complications in the safety analysis. In both groups, severe complications were uncommon. Diode laser TSCPC and CCT had nearly equivalent clinical efficacy in treating intractable glaucoma, while CCT demonstrated a better IOP-lowering effect in non-Asian. Both cyclodestructive procedures have a comparable safety profile.

Diode Laser Transscleral Cyclophotocoagulation With a Novel Low-Cost Torchlight Method of Trans-Corneal Transillumination in Refractory Pediatric Glaucoma

PRCIS

Trans-corneal transillumination (TI) aided transscleral cyclophotocoagulation (TSCPC) for intraocular pressure control of refractory pediatric glaucoma was found to be effective at 1 year.

PURPOSE

To study 1-year outcomes of diode laser TSCPC with trans-corneal TI using a novel low-cost torchlight method in refractory pediatric glaucoma.

METHODS

This prospective interventional study included children with refractory glaucoma who underwent TSCPC with the Oculight laser system (IRIS Medical Instruments) with trans-corneal TI (TSCPC-TI) using a novel low-cost torchlight method. Children completing a minimum 1-year follow-up were analyzed. They were compared with a historical control group of children who underwent TSCPC without TI (TSCPC-No-TI) at the 1-year follow-up period. We analyzed the mean laser energy delivered, post-laser intraocular pressure reduction, number of antiglaucoma medications (AGM), the requirement of retreatment and complications of the procedure in both groups.

RESULTS

Forty-two eyes of 35 patients comprised the TSCPC-TI group and were compared with 31 eyes of 21 patients in the TSCPC-No-TI group. The TSCPC-TI group required lower energy than the TSCPC-No-TI group (24.7±7.8 J vs. 47.2±10.9 J, P <0.0001). Mean topical antiglaucoma drug requirement decreased from 2.9±0.08 before treatment to 0.66±0.8 at the end of 1 year in TSCPC-TI and from 2.6±1.0 before treatment to 0.6±0.77 in the TSCPC-No-TI groups, respectively ( P =0.15). There was a significantly reduced dependence of oral acetazolamide in the TSCPC-TI group at 1-year follow-up [5.7% vs. 61.9%, respectively ( P <0.001%)]. No adverse event of hypotony or choroidal detachment was noted in any group.

CONCLUSIONS

TSCPC aided by TI with a low-cost torchlight for pediatric refractory glaucoma was found to be effective at 1 year in reducing intraocular pressure and the burden of medication.

Comparison of two protocols of diode laser transscleral cyclophotocoagulation in refractory glaucoma

INTRODUCTION

Diode laser transscleral cyclophotocoagulation (DLTSCPC) remains the most commonly used cyclodestructive procedure. Nonetheless, there is no common consensus on a standardized technique.

METHODS

In this prospective randomized pilot study we compare the "pop"-titrated and "slow-burn" DLTSCPC techniques for a follow-up period of 3 months. The major outcomes of this study were intraocular pressure (IOP) before and after the procedure and the incidence of adverse events. Furthermore, postoperative pain, postoperative intraocular inflammation and corrected distance visual acuity (CDVA) were evaluated.

RESULTS

Mean baseline IOP decreased from 37.9 ± 12.7 mmHg in the pop group and 41.2 ± 9.6 mmHg in the slow-burn group to 20.3 ± 13.9 mmHg and 21.3 ± 13.4 mmHg at the final follow-up visit, corresponding to a 45.8 ± 31.7% and 46.3 ± 32.6% reduction respectively. 64.3% and 57.1% of patients had IOP ≥6 and≤ 21 mmHg in the pop and slow-burn groups respectively. The occurrence of adverse events was similar in both groups, with 1 case of hyphema in the pop group and 2 cases in the slow-burn group, and 1 case of hypotony in each group. Mean CDVA remained unchanged until the end of follow-up from 2.05 ± 0.84 to 2.04 ± 0.8 logMAR in the pop group and from 1.93 ± 0.78 to 1.89 ± 0.7 logMAR in the slow-burn group. Nonetheless, 4 eyes in each group encountered CDVA loss. Postoperative pain and inflammation were also similar between groups.

DISCUSSION

At the 3rd postoperative month, safety and efficacy was similar in the two techniques. The relative ease of the slow-burn technique may make its application more appealing to ophthalmic surgeons beyond glaucoma specialists.

Primary slow-coagulation transscleral cyclophotocoagulation laser treatment for medically recalcitrant neovascular glaucoma

AIMS

To report treatment outcomes of slow-coagulation continuous-wave transscleral cyclophotocoagulation (TSCPC) as an initial surgical intervention in patients with neovascular glaucoma (NVG).

METHODS

A retrospective study including 53 patients (mean age of 69.6±16.6 years and mean follow-up of 12.7±8.9 months) with a diagnosis of NVG and no previous incisional glaucoma or cyclophotocoagulation surgeries. All patients underwent slow-coagulation continuous-wave TSCPC (1250-milliwatt power and 4-second duration).Primary outcome measure was surgical success defined as an intraocular pressure (IOP) from 6 to 21 mm Hg with a reduction ≥20% from baseline, no reoperation for glaucoma and no loss of light perception vision. Secondary outcome measures include IOP, glaucoma medications, visual acuity (VA) and complications.

RESULTS

IOP decreased from 40.7±8.6 mm Hg preoperatively to 18.4±12.2 mm Hg postoperatively (p<0.001). The preoperative number of glaucoma medications dropped from 3.3±1.1 at baseline to 2.0±1.5 at the last postoperative visit (p<0.001). The cumulative probabilities of success at 12 and 24 months were 71.7% and 64.2 %, respectively. Mean logarithm of the minimum angle of resolution VA was relatively unchanged from 2.27±0.63 to 2.25±0.66 at the last follow-up visit (p=0.618). The most common observed complications were decrease in baseline VA (13.2%) and anterior chamber inflammation (9.4%).

CONCLUSIONS

Slow-coagulation TSCPC is an effective and relatively safe initial surgical intervention in medically uncontrolled NVG.

A new approach for CW-TSCPC to improve its safety and efficacy in glaucoma treatment

PURPOSE

The goal of our study was to compare the outcomes of transscleral diode cyclophotocoagulation using a new protocol with new settings. In fact, we targeted the ciliary body guided by transillumination, reduced the energy applied at each spot, and enlarged the treatment area posteriorly from the pars plicata to the pars plana.

PATIENTS AND METHODS

Data were collected retrospectively from two groups of glaucoma patients. The first group of patients underwent transscleral diode laser cyclophotocoagulation as usual, with one-row applications of a maximum of 1200mW of energy and a duration of 2000ms. The second group was treated in three rows, using the same settings as the first group. Transillumination was used continuously during all of our procedures, to focus accurately on the location of the ciliary body. Outcome measures included intraocular pressure (IOP) and visual acuity (VA) at baseline and at a minimum of 3 months postoperatively, as well as complications occurring up until last follow-up visit. Patients were considered successfully treated if their intraocular pressure was lowered by at least 25% compared to their baseline or if their intraocular pressure was less than 21mmHg after the procedure, with or without glaucoma medications.

RESULTS

Sixty eyes were treated with the one-row protocol, followed by 508 eyes treated with the three-row protocol. The mean follow-up was 19 (range 3-31) months. Success rates were 62% and 86% for the one-row group and three-row group, respectively. The IOP decrease was 40.5% (a mean reduction from 37.5±8.1mmHg to 22.3±10.2mmHg) in the one-row group and 57.6% in the three-row group (mean reduction from 36.05±10.4mmHg to 15.7±7.3mmHg), which was statistically significant in each group (P=0.0001). Additionally, a significant improvement in efficacy was found in the 3-row compared to the 1-row group (P=0.0001) No significant difference was found in VA before or after the procedure or between the 2 groups. No serious complications were reported.

CONCLUSIONS

Diode laser TSCPC is a practical, rapid and well-tolerated procedure. The treatment protocol used, with lower energy levels applied to the eye, guided systematically by transillumination and targeting a wider area, appears to be safer and more effective.

Micropulse transscleral cyclophotocoagulation in a Taiwanese population: 2-year clinical outcomes and prognostic factors

PURPOSE

To evaluate the 2-year efficacy and safety of micropulse transscleral cyclophotocoagulation (MP-TSCPC) in Taiwanese patients with glaucoma.

METHODS

We included the patients who received standardized MP-TSCPC with follow-up examinations on a regular basis for 24 months. Treatment success was defined as the attainment of a postoperative intraocular pressure (IOP) between 6 and 21 mmHg or a ≥ 20% reduction in IOP from baseline without an increase in glaucoma medications.

RESULTS

A total of 60 eyes from 56 patients who underwent MP-TSCPC for refractory glaucoma were included. The median age at MP-TSCPC intervention was 58.9 ± 12.4 years. The percentage of treatment success was 88.3% at 3 months, 83.3% at 6 months, 78.3% at 12 months, and 75.0% at 24 months. The mean baseline IOP prior to MP-TSCPC was 34 ± 11.9 mmHg (range 14-56 mmHg). The mean postoperative IOP decreased to 20.9 ± 10.0 mmHg, 18.0 ± 7.8 mmHg, 17.5 ± 6.4 mmHg, and 18.2 ± 7.1 mmHg after 3 months, 6 months, 12 months, and 24 months, respectively, in successful cases. The mean number of glaucoma medications at baseline was 3.8 ± 0.2, and the mean numbers of glaucoma medications at postoperative months 3, 6, 12, and 24 were 2.6 ± 0.7, 2.8 ± 0.6, 2.5 ± 1.4 and 2.6 ± 1.4, respectively, in successful cases. Younger age and prior CW-TSCPC significantly contributed to surgical failure in the multivariate model. Complications after MP-TSCPC included mild anterior chamber inflammation, conjunctival hemorrhage, hypotony, and mydriasis, and all subsided after treatment. None of the eyes developed vitreous hemorrhage, cystoid macular edema, or phthisis bulbi in the late postoperative period.

CONCLUSIONS

This study demonstrated that younger age and prior CW-TSCPC were risk factors for MP-TSCPC failure within 2 years. MP-TSCPC might be safe and effective for refractory glaucoma patients with maximal antiglaucoma medications.

Anterior Chamber Laser Flare Photometry After Diode Laser Cyclophotocoagulation

BACKGROUND

The aim of this study was to evaluate changes in intraocular inflammation according to energy delivered per eye during transscleral diode laser cyclophotocoagulation (TDLC) in refractory glaucoma using laser flare (LF) photometry and to investigate the relationship between the change in anterior chamber flare values ​​and the success of TDLC.

METHODS

Patients who underwent TDLC for refractory glaucoma and had LF photometry data were analyzed retrospectively. We recorded the best-corrected visual acuity, intraocular pressure (IOP) with Goldmann applanation tonometer, number of anti-glaucoma medications, LF photometry values (ph/ms) on pre-and postoperative days 1, 10 and 30.

RESULTS

The mean laser power applied during TDLC procedure was 2.45±0.35W. The mean laser duration was 2.09±0.28sec. The mean total energy applied per eye was 114.69±16.13 J, the mean number of pulses was 22.43±4.3. While the mean LF value was 49.71±11.99ph/ms preoperatively, it was 63.94±12.41ph/ms at the postoperative 30^th day. Possible predictors of success of TDLC were investigated using linear regression analysis (R adjusted 0.454 p=0.001). The IOP decrease at postoperative 30^th day was significantly related to the difference between the postoperative 1^st day and the preoperative LF (p=0.025, B/95% CI -0.358/-0.107- -0.008), and total cyclodiode energy delivered per eye (joules) (p=0.016, B/95% CI -0.396/-0.287 - -0.031).

CONCLUSIONS

Anterior chamber flare values increases after TDLC, though it does not regress to the preoperative level on the postoperative 30th day. Total cyclodiode energy delivered per eye and the difference between the postoperative 1^st day and the preoperative LF can be used to predict TDLC response.

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.

Efficacy and Safety of Ultrasound Cycloplasty for Refractory Glaucoma: A 3-Year Study

PRECIS

Ultrasound cycloplasty (UCP) treatment using high-intensity focused ultrasound is an effective and safe therapy to reduce intraocular pressure (IOP) in patients with refractory glaucoma over a 3-year period.

PURPOSE

The purpose of this study was to evaluate the 3-year efficacy and safety of UCP in patients with refractory glaucoma.

PATIENTS AND METHODS

In all, 104 patients with refractory glaucoma recruited from 2 university hospitals underwent UCP. Examinations were performed 7 days, 1 week, 1, 3, 6, 12, 24, and 36 months after the UCP procedure. Primary outcomes were therapeutic success at 3 years (IOP reduction from baseline ≥20% and IOP >5 mm Hg without other surgical procedures) and vision-threatening complications. Secondary outcomes included mean IOP change from baseline at each follow-up visit, medication use, complications, and subsequent UCP and/or other postsurgical interventions.

RESULTS

At 3 years post-UCP, the therapeutic success rate was 55%. For 75% of the patients, results were obtained with only one procedure. For the overall study population, IOP was reduced significantly (P<0.005) from 27.6±8.9 mm Hg (n=3.0 topical hypotensive medication) to 17.0±6.8 mm Hg at 36 months (n=2.8 topical hypotensive medication) (33% reduction). For the success patients, the IOP was initially 29.3±8.8 mm Hg (n=3.0 topical hypotensive medication) and 15.6±4.3 mm Hg at 36 months (n=2.8 topical hypotensive medication) (43% reduction). The rate of complications was low and there were no cases of phthisis.

CONCLUSION

The UCP procedure was efficacious with few complications and should be considered as an alternative to other IOP-lowering therapies including laser cyclocoagulation in patients with refractory glaucoma.

Two-year efficacy after first transscleral controlled cyclophotocoagulation in patients with and without pseudoexfoliation

Purpose

Transscleral controlled cyclophotocoagulation (COCO) is a transscleral 810-nm diode laser cyclophotocoagulation that automatically adjusts the applied laser energy utilizing an optical feedback loop. The present study investigates the influence of pseudoexfoliation (PEX) on the efficacy of COCO in a Caucasian study population.

Methods

Retrospective data from 130 consecutive eyes were analyzed during a 2-year follow-up. Baseline characteristics, intraocular pressure (IOP), number of IOP-lowering medications, visual field, best-corrected visual acuity (BCVA), and secondary surgical interventions (SSI) were analyzed. The primary endpoint was IOP reduction at M24 compared to baseline, and the secondary endpoints were IOP course, reduction of IOP-lowering medications, surgical success, and IOP-lowering SSIs stratified by PEX and baseline IOP.

Results

IOP reductions of −35, −39, −25, −25, −23, −34, and −36% could be achieved from baseline to D1, W1, M1, M3, M6, M12, and M24 (all p < 0.001), respectively, while there was a significant overall reduction over time (p < 0.001) in the number of topical IOP-lowering medications postoperatively. The proportion of eyes requiring additional systemic IOP-lowering medication reduced from 31 to 0% at M24 (p = 0.025). Eyes without PEX and IOP < 30 mmHg at baseline had the lowest risk for IOP-lowering SSIs (p < 0.03). BCVA dropped at M12 (0.25 [95% CI: 0.12–0.38]), and the drop persisted during the following 12 months.

Conclusion

The present study demonstrates a midterm IOP-lowering effect after COCO while reducing the burden for topical and systemic IOP-lowering medications. Patients without PEX and IOP < 30 mmHg have a lower risk of SSI. The procedure per se cannot be excluded as causative for the decreased postoperative BCVA. Further prospective investigations are suggested.

Efficacy and safety of transscleral cyclophotocoagulation in Swedish glaucoma patients

PURPOSE

To retrospectively evaluate the efficacy and safety of all transscleral cyclophotocoagulation (TCP) treatments performed during a 5-year period.

METHODS

Medical records of all patients, who had undergone TCP treatment between 2010 and 2014 at Umeå University Hospital, Sweden, were evaluated. Clinical data including intraocular pressure (IOP), visual acuity (VA), number of topical glaucoma medications, use of oral acetazolamide, retreatments and complications during a 2-year follow-up were registered. Global success was defined as IOP 6-18 mmHg with or without glaucoma medication.

RESULTS

Three hundred patients underwent TCP during the time period. Mean IOP at baseline was 29.3 ± 11.0 (mean ± standard deviation) mmHg (n = 297) with a mean reduction of 11.5 (±12.0) mmHg at 1 year (n = 258; p < 0.001) and 12.6 (±12.0) mmHg at 2-year follow-up (n = 245; p < 0.001). Global success at 2 years was 64%, achieved by a mean of 1.2 treatments (n = 257). The number of topical glaucoma medications at baseline was 3.1 (±1.0; n = 296) and was reduced by 0.9 (±1.0) medications at 2 years (n = 244; p < 0.001). Use of oral acetazolamide decreased from 30% (n = 90) at baseline to 5.3% (n = 13) at 2 years. In eyes with Snellen VA ≥ 0.1, the mean VA at baseline was 0.55 (±0.3) logarithm of the minimum angle of resolution (logMAR; n = 132) and 1.1 (±0.9) logMAR (n = 76) at 2 years (p < 0.001). No cases of phthisis bulbi were found.

CONCLUSION

This study displays a substantial and long-term reduction of IOP following TCP with a decrease in topical and oral glaucoma medications. The treatment appears to be safe but the decrease in VA during follow-up is a concern that needs further evaluation.

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

PURPOSE

The purpose of this study was to evaluate the efficacy and safety of subliminal cyclophotocoagulation using a 25% duty cycle diode laser (Supra 810, SubCyclo, Quantel Medical).

METHODS

This was a pilot study of patients who underwent a SubCyclo photocoagulation procedure with a 25% duty cycle, between April 2016 and April 2017 at the Glaucoma Institute of Saint Joseph Hospital of Paris. All patients presented with an evolving moderate to severe glaucoma that were resistant to previous surgical treatments or with a contraindication for filtration surgery. Laser settings were programmed as follows: power 2000 mW, "on" time 0.63 ms, "off" time 1.9 ms, and 25% duty cycle per 100 seconds to each eye.

RESULTS

A total of 44 eyes of 34 patients were treated with subliminal cyclophotocoagulation, with a mean follow-up time of 12 months. Surgical success was defined as IOP ranging 6 to 21 mm Hg or a 20% IOP reduction at the last 12 months follow-up visit. The mean age of patients was 63.83±16.2 years. The mean preoperative IOP was 32.8±11.8 mm Hg which then decreased postoperatively to 24.02±7.03 mm Hg after 1 day, 18.34±8.31 mm Hg after 1 week, 18.26±8.53 mm Hg after 1 month, 20.5±8.53 mm Hg after 3 months, 18.9±9.2 mm Hg after 6 months and 18.8±9.3 mm Hg after 12 months. Our preliminary study using Subcyclo transscleral cyclophotocoagulation with a 25% duty cycle showed a 37% IOP reduction from the baseline after 3 months with a single laser session and a 45% reduction at the last 12 months follow-up, after more than one laser session. The mean number of ocular antihypertensive medications used was 3.4±1.7 before treatment which decreased to 3.0±1.6 after treatment. No significant complications or anatomic modifications were found after subliminal cyclophotocoagulation.

CONCLUSIONS

Subliminal cyclophotocoagulation with a 25% duty cycle is a safe and effective procedure for reducing IOP in cases of refractory glaucoma and seems to be safer than conventional transscleral cyclophotocoagulation.

Cyclodestructive procedures for refractory glaucoma

BACKGROUND

Cyclodestructive procedures are often used in patients with refractory glaucoma who have failed to achieve lower intraocular pressure (IOP) from filtration procedures and maximal medical therapy. Destruction of the ciliary body helps to lower IOP by reducing aqueous humor formation. Of the many types of cyclodestructive procedures, laser cyclophotocoagulation (CPC) has become the most common surgical method for reducing aqueous inflow. Options for CPC are wide-ranging: they can be performed using a neodymium:yttrium-aluminum-garnet (Nd:YAG) or diode laser and laser energy can be delivered by either the contact or non-contact method. Another cyclodestructive procedure is endoscopic cyclophotocoagulation (ECP), which the ophthalmologist can use selectively to target the ciliary epithelium and ablate ciliary body tissue. There is debate regarding which cyclodestructive method is best and how they compare to other glaucoma surgeries.

OBJECTIVES

To assess the relative effectiveness and safety of cyclodestructive procedures compared with other procedures in people with refractory glaucoma of any type and to assess the relative effectiveness and safety of individual cyclodestructive procedures compared with each other.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2018, Issue 9); Ovid MEDLINE; Embase.com; PubMed; LILACS BIREME; ClinicalTrials.gov and the WHO ICTRP. The date of the search was 21 September 2018.

SELECTION CRITERIA

We included randomized controlled trials or quasi-randomized trials in which participants underwent a secondary procedure for refractory glaucoma. We included trials with any laser type, route of administration, and laser settings. The primary comparison was any cyclodestructive procedure versus another glaucoma treatment, and the secondary comparisons were individual cyclodestructive procedures versus another cyclodestructive procedure.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed the titles and abstracts from the database searches, and after retrieving the full-text reports of those that were potentially relevant, classified the full-text articles as included or excluded. Two review authors independently extracted data from the included studies and assessed the risk of bias. Discrepancies were resolved by discussion or by consultation with a third review author when necessary.

MAIN RESULTS

We included five trials reporting data for 330 eyes (326 participants). One study to had a low risk of bias for most domains and the other studies had an overall unclear risk of bias. This review includes four different comparisons: 1) ECP versus Ahmed implant, 2) micropulse CPC versus continuous-wave CPC; 3) CPC with a diode versus Nd:YAG laser; and 4) CPC with an Nd:YAG laser emitting 8J versus 4J.No study reported data for our primary outcome, change from baseline in pain severity as reported by the participant or change in number of pain medications.For our primary comparison, we included one trial that compared ECP with the Ahmed implant. At 12-month follow-up, the mean difference (MD) in IOPs between groups was -1.14 mmHg (95% confidence interval (CI) -4.21 to 1.93; 58 participants; low-certainty evidence (LCE)). At 24 months postintervention, we found very LCE suggesting that visual acuity may be better among participants in the ECP group than in the Ahmed implant group (MD -0.24 logMAR, 95% CI -0.52 to 0.04; 54 participants), and the difference in the mean number of glaucoma medications used by participants in each group was unclear (MD -0.50, 95% CI -1.17 to 0.17; 54 participants; very LCE). Reported adverse events in the ECP group (34 participants) were one case each of hypotony, phthisis bulbi, retinal detachment, and choroidal detachment; in the Ahmed implant group (34 participants) there was one case of endophthalmitis, two cases of retinal detachment, and six cases of choroidal detachment.Three types of comparisons from four included studies provided data for our secondary comparisons. In the study that compared micropulse with continuous-wave CPC, median IOP was reported to be similar between the two groups at all time points. At 18 months postintervention, the median number of IOP-lowering medications was reduced from two to one in both groups. One participant in the micropulse and two in the continuous group exhibited worsened visual acuity. One case of prolonged inflammation was seen in the micropulse group (23 participants). Seven cases of prolonged inflammation, five cases of hypotony, and one case of phthisis bulbi were seen in the continuous group (23 participants).Two studies compared CPC using a semiconductor diode versus an Nd:YAG laser. At 12 months postintervention, the MD in IOP was 1.02 mmHg (95% CI -1.49 to 3.53) in one study (LCE). The second study did not report mean IOP beyond three months of follow-up. Neither study reported the mean change in best-corrected visual acuity or number of glaucoma medications. Both studies reported hypotony as an adverse event in three participants in each study.One study compared different energy settings of the same Nd:YAG laser. At 12-month follow-up, visual acuity was unchanged or improved in 21 of 33 participants in the 8J group and 20 of 27 participants in the 4J group (risk ratio 0.86, 95% CI 0.61 to 1.21; very LCE). More participants in the 8J group reduced the number of medications taken compared with the 4J group (RR 1.49, 95% CI 0.76 to 2.91; 50 participants; very low-certainty evidence). The presence of fibrin or hyphema were seen in five participants who received 8J and none who received 4J. There was a severe anterior chamber reaction in 11 of 26 (42%) participants who received 8J of energy and 2 of 21 (10%) participants who received 4J of energy.

AUTHORS' CONCLUSIONS

Evidence from five studies included in this review was inconclusive as to whether cyclodestructive procedures for refractory glaucoma result in better outcomes and fewer complications than other glaucoma treatments, and whether one type of cyclodestructive procedure is better than another. The most commonly reported adverse events across all five studies were hypotony and phthisis bulbi. Large, well-designed randomized controlled trials are needed. Patient-reported outcomes such as pain and quality of life should be considered as primary outcomes or important secondary outcomes of future trials.

Efficacy and safety of pop-titrated versus fixed-energy trans-scleral diode laser cyclophotocoagulation for refractory glaucoma

PURPOSE

To compare the efficacy and safety of pop-titrated versus fixed-energy diode laser trans-scleral cyclophotocoagulation (DLTSC) for refractory glaucoma.

METHODS

This is a prospective, interventional, longitudinal, and comparative case-control study. Patients with refractory glaucoma treated with pop-titrated DLTSC were compared to a fixed-energy DLTSC control group. Variables analyzed included: age, gender, diagnosis, pre- and post-treatment intraocular pressure (IOP). Success rate, anti-glaucoma medications reduction, and complications were analyzed at day 90 post-treatment. Primary success criterion consisted of eyes with a postoperative IOP ≤ 22 mmHg or a 30% reduction of pre-treatment IOP and managed with topical anti-glaucoma medications only.

RESULTS

A total of 68 eyes from 67 patients were included for analysis: 30 in the pop-titrated group and 38 in the fixed-energy group. Therapeutic success was achieved in 56-72% of the pop-titrated group versus 47-52% in the fixed-energy group considering the 3 different criteria analyzed (p = 0.23-0.4). There was a 22% (from 4.1 to 3.2 drugs) reduction of anti-glaucoma medications in the pop-titrated group, compared to 32% (from 3.5 to 2.4 drugs) in the fixed-energy group (p = 0.42). Five eyes (13.1%) developed hypotony, all of which belonged to the fixed-energy group (p = 0.048).

CONCLUSIONS

Pop-titrated DLTSC represents an effective and safe option for the management of refractory glaucoma. We found no statistically significant difference in success rates among both groups. However, there was a significantly higher risk of hypotony in eyes treated with the fixed-energy protocol.

Comparison of Outcomes between Endoscopic and Transcleral Cyclophotocoagulation

Importance: Traditionally cyclophotocoagulation has been reserved as a treatment of last resort for eyes with advanced stage glaucoma, but increasingly it is offered to eyes with less severe disease. Endoscopic approaches in particular are utilized in increasing numbers of patients despite only a small number of publications on its results. Objective: The purpose of this study was to compare the efficacy and safety of endoscopic and transcleral cyclophotocoagulation (ECP and TCP) procedures in eyes with refractory glaucomas. Design, Setting, and Participants: A chart review was performed on consecutive patients who underwent ECP and TCP at a tertiary ophthalmology care center between January 2000 and December 2010. Cases with fewer than 3 months of follow-up or that had concurrent pressure reducing procedures were excluded. The main outcome measures examined were intraocular pressure (IOP), number of glaucoma medications, best corrected visual acuity (BCVA), additional glaucoma procedure required, and complications. Main Outcomes and Measures: Forty-two eyes (42 patients) that underwent ECP and forty-four eyes (44 patients) that underwent TCP were identified. The TCP group had a statistically higher mean age (71.2 ± 16.7 vs. 58.1 ± 22.9 years, respectively), larger proportion of neovascular glaucoma (40.9% vs. 16.7%), worse initial BCVA (logMAR 2.86 vs. 1.81), and higher preoperative IOP (45.3 vs. 26.6 mmHg) than the ECP group. At 12 months follow-up, the mean IOP difference between groups was not statistically significant, although the change in IOP from baseline to 12 months was greater for the TCP group (p = 0.006). The rates of progression to no light perception (NLP) and phthisis bulbi were significantly higher amongst TCP eyes than ECP eyes (27.2% vs. 4.8%, p = 0.017, and 20.5% vs. 0%, p = 0.003, respectively). Of these eyes that progressed, a majority had neovascular glaucoma (NVG). Corneal decompensation was the most frequent complication following ECP (11.9%). Conclusions and Relevance: In patients with preoperative BCVA of 20/400 or better, overall complication rates (cystoid macular edema, exudative retinal detachment, inflammation, cornea decompensation) were higher after ECP than with TCP. In refractory glaucomas in a real world setting (not a trial), TCP was more frequently used in ischemic eyes. TCP was associated with a higher rate of progression to phthisis bulbi and loss of light perception than ECP. However, ECP was associated with a clinically significant rate of corneal decompensation. These outcomes likely were related to the severity of underlying ocular diseases found in these eyes.

Intraocular Pressure Outcomes Following Transscleral Diode Cyclophotocoagulation Using Long and Short Duration Burns

PURPOSE

The purpose of this study was to compare outcomes of transscleral diode cyclophotocoagulation using short duration (SD) versus longer duration (LD) treatment.

PATIENTS AND METHODS

Data were collected retrospectively on patients with glaucoma who underwent cyclophotocoagulation with LD (4000 ms) treatment with variable power ≤1000 mW versus SD using 1500 ms with variable power ≤2000 mW. The outcome measures included: intraocular pressure (IOP) at 12 months, decrease in number of antiglaucoma medications, complications and visual acuity (VA) at the final follow-up visit.

RESULTS

There were 71 patients and 70 patients in the SD and LD groups, respectively. The mean IOP±SD pretreatment baseline was 33±10 versus 36±10 mm Hg for SD and LD groups, respectively (P>0.05). At 1 year postoperatively, the IOP decreased significantly in both groups (16.7 vs. 17.4 mm Hg for SD and LD, respectively; P<0.0001). This decrease in IOP was comparable between groups (P=0.5). The average number of IOP lowering medications were 2.5 and 2.9 at baseline in the SD and LD groups, respectively, and decreased to 1.3 in both groups (P=0.83). The mean LogMAR VA decreased significantly from 1.87 at baseline to 1.96 at 1 year in the SD group (P=0.276), and 2.03 to 2.3 (P≤0.001) in the LD group, this change was comparable (0.19; P=0.075) between the 2 groups. Complications were also comparable.

CONCLUSIONS

Both LD and SD burns during cyclophotocoagulation effectively lowered IOP at 1 year. Neither treatment resulted in a greater reduction of IOP. LD treatment appeared to result in a decrease in VA and greater postoperative inflammation.

Diode laser cyclophotocoagulation paves way to a safer trabeculectomy in eyes with medically uncontrollable intraocular pressure

High intraocular pressure (IOP) not responding to systemic and topical anti-glaucoma medications renders the eye at risk for both intra- and post-operative complications of glaucoma filtration surgery. Laser cyclophotocoagulation is able to lower IOP in such refractory glaucoma eyes and may make the surgical event safer. This study assessed diode laser cyclophotocoagulation (DLCP) when used as a temporary measure for lowering IOP prior to performing trabeculectomy. This study is a  retrospective analysis of cases planned for trabeculectomy surgery, uncontrolled on maximally tolerable systemic anti-glaucoma medications. They were analysed for response to DLCP in terms of IOP control, vision-related complications, increased inflammation, post-trabeculectomy hypotony and chances of phthisis and ciliary shutdown. Twelve eyes of ten patients aged 35-65 years were identified and all followed up for at least 2 years. One week following DLCP, the IOP (mean ± SD) declined by 51 % from 46.8 ± 5.4 to 22.8 ± 3.3 mmHg. The IOP was further reduced to 15.4 ± 2.7 mmHg at 4 weeks after trabeculectomy; it remained in the mid-teens for a minimum of 2 years in all cases. The mean (±SD) visual acuity improved from 1.4 ± 0.4 to 0.8 ± 0.4 LogMAR equivalents following trabeculectomy. In four eyes, phacoemulsification was performed 5-7 months after trabeculectomy with improvement in best-corrected visual acuity. One patient developed transient hypotony, post-trabeculectomy, which resolved by 6 days. There were no other complications like increased inflammation, prolonged hypotony or suprachoroidal haemorrhage. DLCP is, thus, effective and safe for temporarily controlling IOP; thereby trabeculectomy can be performed in a quieter ocular milieu.

Update on results and complications of cyclophotocoagulation

PURPOSE OF REVIEW

This review highlights recently published studies on transscleral and endoscopic diode cyclophotocoagulation (TCP, ECP) and summarizes the treatment results and complications.

RECENT FINDINGS

Although both TCP and ECP are efficacious procedures for the treatment of refractory glaucoma, no consensus exists for optimum treatment protocol. TCP has mainly been used as a last-resort treatment for intractable glaucoma with very limited visual potential. Repeated treatment is often required. Serious complications include vision loss, hypotony, and phthisis. High treatment energy per session and underlying abnormality seem risk factors for these complications. Recent growing numbers of investigations are giving promising results for TCP as a primary surgery in eyes with good vision. Although ECP came later into clinical use for glaucoma treatment, it is becoming more accepted and no longer reserved for end-stage cases. ECP is most commonly performed in conjunction with cataract surgery and shows overall good success with relatively low complication rates. Serious complications include hypotony, phthisis, cystoid macular edema, and retinal detachment.

SUMMARY

Recent literatures suggest that both TCP and ECP are performed increasingly as the primary surgery for various types and stages of glaucoma. Both treatments are effective procedures, although potential for serious complications exists.

Risk factors for hypotony after transscleral diode cyclophotocoagulation

PURPOSE

To evaluate risk factors associated with hypotony after transscleral diode cyclophotocoagulation (TCP) in East Asian patients with intractable glaucoma.

METHODS

Clinical data from 90 eyes of 90 patients who underwent TCP for various indications at Singapore National Eye Centre between 2005 and 2007 were retrospectively reviewed. Baseline intraocular pressure (IOP) was compared with postoperative IOP at 1 month, 3 to 6 months, and 1 year. Mean total energy per session was calculated in Joules and retreatment rates were recorded. Change in visual acuity and number of medications were recorded at 1-year follow-up. Success was defined as percentage of patients achieving an IOP of 5 to 21 mm Hg with or without medications. Hypotony was defined as IOP <5 at the end of 1-year follow-up period. Factors, such as underlying diagnosis, total energy used, age, earlier operations, and retreatment rates, which may influence the development of hypotony were analyzed using univariate analysis.

RESULTS

Success was achieved in 54.0% of patients. Mean total energy used was 83.3±31.7 J. Mean pretreatment IOP was 41.8±12.9 mm Hg, which reduced to 20.7±12.1 mm Hg (P<0.001) at 1 month and 17.8±12.9 mm Hg (P<0.001) at 1 year. Sixteen (39.0%) patients developed hypotony. Univariate analysis showed that neovascular glaucoma patients have a significantly increased risk for developing hypotony post TCP (odds ratio=9.17, 95%; confidence interval=1.85-45.36).

CONCLUSION

Underlying diagnosis of neovascular glaucoma is a significant risk factor for hypotony post TCP.

The UK National Cyclodiode Laser Survey

PURPOSE

To evaluate current practice of transscleral diode laser cyclophotocoagulation (cyclodiode) laser treatment among consultant ophthalmologists in the United Kingdom.

METHODS

A 31-question survey was emailed to all practising consultant ophthalmologists who were members of the Royal College of Ophthalmologists. All non-responders were sent a postal version of the questionnaire. This paper looked at cyclodiode practice patterns and consisted of questions on demographic data, transillumination, and power settings, factors influencing practice, post-operative care, and repeat treatment.

RESULTS

A total of 510 participants (53.6%) responded. A total of 180 (35.3%) responders reported performing cyclodiode laser treatment, of which 84 (46.7%) were glaucoma subspecialists (GSS). Initial median power settings used were 1500 mW and 2000 ms. The average number of applications delivered per sitting was 25.5 ± 1.2 applications for GSS vs 20.6 ± 2.0 for non-GSS in a seeing eye (P = 0.0013). In all, 65% routinely transilluminated the globe of which 78% were GSS and 52.3% were non-GSS (P = 0.0009). In all, 43% of the GSS vs 17% of the non-GSS lowered power settings in uveitic glaucoma (P = 0.013). In blind eyes, 30% of the GSS vs 12% of the non-GSS increased energy levels (P = 0.0014). In all, 60% of the responders performed cyclodiode at any visual acuity, whereas 22% performed combined cyclodiode and cataract surgery.

CONCLUSIONS

This survey highlights a wide variation in the use of cyclodiode laser treatment amongst GSS and non-GSS. However, the most frequently used practice may not be the optimal practice. A more individualised parameter according to the condition of the eyes may optimise the outcome.