Deep sclerectomy in normal-tension glaucoma with and without mitomycin-c

PURPOSE

To compare the outcome of deep sclerectomy (DS) with and without mitomycin-C (MMC) in patients with normal-tension glaucoma (NTG).

METHODS

We prospectively analysed the results of 37 eyes of 37 consecutive patients with NTG (age; mean ± SD; 64 ± 7 years) who underwent DS with a collagen implant. Patients were randomized to the MMC and non-MMC groups. Subconjunctival MMC (0.4 mg/ml for 3 min) was used intraoperatively in 15 of 37 eyes. We defined total success as 25% reduction in intraocular pressure (IOP) without medication. Follow-up time was 12 months.

RESULTS

The mean preoperative IOP was significantly reduced from 15.2 ± 2.8 mmHg to 9.3 ± 2.7 (p < 0.001) in the MMC group after 12-month follow-up and from 15.1 ± 2.9 mmHg to 11.8 ± 2.0 (p < 0.001) in the non-MMC group. At 12 months, the mean IOP was significantly lower in the MMC group (p = 0.003) compared with the non-MMC group. Total success was achieved in 10 of 15 eyes (67%) in MMC group and in nine of 22 eyes (41%) in non-MMC group (p = 0.12). The number of glaucoma medications was decreased from 2.2 ± 0.8 to 0.5 ± 1.2 in MMC group (p = 0.001) and from 2.6 ± 1.0 to 0.5 ± 0.7 in non-MMC group (p < 0.001). Goniopuncture was performed in seven eyes (47%) in the MMC group, compared with 16 eyes (73%) in the non-MMC group (p = 0.13). IOP < 10 mmHg was achieved in seven of 15 eyes in the MMC group and in two of 22 in the non-MMC group (p = 0.009). Complication rate was low, and no difference between groups was evident.

CONCLUSION

Deep sclerectomy seems to be effective and safe in reducing IOP in patients with NTG. Intraoperative use of MMC results in lower postoperative IOP 12-month postoperatively without increased rate of complications.

Lysyl oxidase-like 2 level and glaucoma surgical outcomes

PURPOSE

To evaluate the levels of TGF-β and lysyl oxidases in both the aqueous humor and in Tenon's tissue in patients with POAG, and to assess their association with bleb morphological features and outcomes of glaucoma surgery.

METHODS

Eighteen POAG patients scheduled to undergo glaucoma surgery and 17 healthy controls were enrolled. At the time of surgery, approximately 0.1 mL aqueous humor through an anterior chamber paracentesis and a 4 × 4-mm sample of Tenon's tissue were obtained. Concentrations of TGF-β and lysyl oxidases (types 1 and 2) were analyzed by ELISA. The bleb morphologic features based on the Moorfields Bleb Grading System were evaluated by bleb photographs.

RESULTS

The TGF-β in Tenon's tissue and lysyl oxidase-like 2 in aqueous humor and in Tenon's tissue were significantly elevated in POAG patients. When POAG patients were divided by outcome 1 year after surgery, lysyl oxidase-like 2 protein was significantly higher in both aqueous humor and Tenon's tissue of the failure group. The level of lysyl oxidase-like 2 protein was significantly correlated with that of TGF-β in the Tenon's tissue. Lysyl oxidase-like 2 level in the aqueous humor (r = 0.563, P < 0.001) and Tenon's tissue (r = 0.760, P < 0.001) had significantly negative correlation with bleb area.

CONCLUSIONS

The TGF-β and lysyl oxidase-like 2 levels at the time of surgery were significantly correlated with 1-year outcomes of glaucoma surgery. The level of lysyl oxidase-like 2 was significantly correlated with that of TGF-β, suggesting induction by TGF-β. Modulation of lysyl oxidase-like 2 levels may have important applications in glaucoma surgery.

Efficacy and safety of deep sclerectomy in childhood glaucoma in Saudi Arabia

PURPOSE

To evaluate the efficacy and safety of deep sclerectomy in childhood glaucoma.

METHODS

A prospective cohort of 120 children presenting with glaucoma to King Abdul Aziz University Hospital (KAUH) was subjected to nonpenetrating deep sclerectomy surgery (NPDS). Eventually, 57 patients had macro perforation and converted to penetrating deep sclerectomy (PDS). Intra-operative mitomycin C (MMC) 0.2 mg/ml was used in all patients. Pre- and postintervention glaucoma indices were assessed. Complete success rate (CSR) was identified as achieving an end-point of intraocular pressure <21 without any antiglaucoma medications. Data were analysed to compare pre- and postintervention changes and to compare both procedures.

RESULTS

After follow-up of 35.8 (34.5) months, NPDS procedure went smooth in 74 eyes of 63 patients. The complete success rate was 79.7%, whereas the overall success rate was 82.4%. Thirteen cases failed. The probability to survive was 74.6% after the 12th month. The mean intraocular pressure (IOP) went down to 11.5 ± 3.0 mmHg compared to 31.9 mmHg preoperatively. Comparing cases with NPDS to those with PDS, the magnitude of IOP reduction (15.8) was higher than that of the PDS (14.8); however, this difference was not statistically significant (p = 0.259). Apart from involuntary perforation of trabeculodescemetic window (TDW), neither intra-operative nor early postoperative complications were observed.

CONCLUSIONS

Deep sclerectomy in childhood glaucoma can effectively reduce the IOP, without the occurrence of serious complications that are commonly seen after trabeculotomy or combined trabeculotomy trabeculectomy.

Efficacy and safety of collagen matrix implants in phacotrabeculectomy and comparison with mitomycin C augmented phacotrabeculectomy at 1 year

BACKGROUND

To assess the efficacy and safety of collagen matrix implant (Ologen) in phacotrabeculectomy.

DESIGN

Prospective, non-randomized, comparative study.

PARTICIPANTS

Sixty-six Asian patients.

METHODS

Thirty three consecutive patients underwent phacotrabeculectomy with Ologen implant and intraocular lens implantation, and 33 subjects recruited as controls underwent surgery with mitomycin C augmentation.

MAIN OUTCOME MEASURES

The primary outcome measure was postoperative intraocular pressure at month 12. Additional postoperative treatments, such as bleb needling, and adverse events were secondary outcomes.

RESULTS

The overall percentage reduction in intraocular pressure was 13% (95% confidence interval 6.7-19.2) in the Ologen group and 26% (95% confidence interval 14.8-37.9) in the mitomycin C group (P = 0.05). At 1 year after surgery (after adjusting for baseline differences), intraocular pressure decreased by 4.2 mmHg (95% confidence interval 2.8-5.6 mmHg) and 5.6 mmHg (95% confidence interval 4.2-7.0 mmHg), respectively (P = 0.16). Needling with 5-fluorouracil was required more often in the Ologen group (39% vs. 6%; P = 0.003). There was similar frequency (<10%) of adverse events in both groups, and there were no complications directly related to the Ologen implant. The blebs in the mitomycin C group had greater central area (P = 0.005), maximal area (P = 0.01) and height (P = 0.005), and were less vascular (P = 0.023) than the Ologen blebs.

CONCLUSIONS

At 1 year, the overall performance of Ologen in combined phacotrabeculectomy was suboptimal compared with combined surgery with mitomycin C. Eyes in the Ologen group required more frequent bleb needling procedures.

One Year of Glaucoma Research in Review: 2012 to 2013

PURPOSE

The objective of this study was to provide the practicing clinical ophthalmologist with an update of pertinent glaucoma literature published from 2012 to 2013.

DESIGN

Literature review.

METHODS

The authors conducted a 1-year (July 1, 2012, to September 30, 2013) English-language glaucoma literature search on PubMed using the following terms: glaucoma, automated perimetry, optic nerve imaging, optical coherence tomography, glaucoma structure and function, intraocular pressure, central corneal thickness, glaucoma medical therapy, neuroprotection, glaucoma laser treatment, secondary glaucoma, glaucoma surgery, and miscellaneous topics in glaucoma.

RESULTS

Of 2659 articles on glaucoma published during our time frame, this review selected original and review articles that reflect novel aspects and updates in the field of glaucoma, while excluding letters to the editor, unpublished works, and abstracts. Preference was given to human research.

CONCLUSIONS

This review focuses on literature that is applicable to ophthalmologists in practice and also highlights studies that may enhance the diagnosis and management of glaucoma.

Clinical features of bleb-related infection: a 5-year survey in Japan

PURPOSE

To present clinical features and microbial data for bleb-related infections obtained by the 5-year-long Japan Glaucoma Society Survey of Bleb-related Infection (JGSSBI).

METHODS

This multicentre prospective observational study was conducted in 82 clinical centres in Japan. A total of 170 bleb-related infections developed in 157 eyes of 156 patients during a 5-year period. The ophthalmological and microbial data were analysed.

RESULTS

The patient age at first infection was 59.3 ± 17.7 years [mean ± standard deviation (SD)], and the period between the last glaucoma surgery and the first infection was 6.9 ± 5.8 years (mean ± SD; range: 0.3-41 years). Bleb leakage was noted significantly more frequently in eyes with repeated infections. The stage of infection at diagnosis was stage I in 91 infections (54%), stage II in 30 infections (18%), stage IIIa in 18 infections (11%), and stage IIIb in 31 infections (18%). Staphylococcus species were the most frequently isolated microbe (41%), followed by Streptococcus species (32%). Streptococcus species, coagulase-negative Staphylococcus, Haemophilus influenzae, and Enterococcus species were the major bacteria isolated in the late-stage infections.

CONCLUSIONS

The JGSSBI project has revealed several characteristics of bleb-related infection in Japan, which include the significance of bleb leakage in the development of repeated infections and the distribution of bacterial isolates.

Inhibition of placental growth factor improves surgical outcome of glaucoma surgery

Excessive post-operative wound healing with subsequent scarring frequently leads to surgical failure of glaucoma filtration surgery (trabeculectomy). We investigated the hypothesis that placental growth factor (PlGF) plays a role in post-operative scar formation, and that it therefore may be a target for improvement of filtration surgery outcome. ELISA experiments showed that PlGF levels were significantly increased in aqueous humour of glaucoma patients and after VEGF treatment, which may indicate an important contribution of this growth factor to wound healing after trabeculectomy. Using a mouse model of glaucoma filtration surgery, we were able to show that intracameral injection of a previously characterized anti-PlGF antibody (ThromboGenics NV) significantly improved surgical outcome by increasing bleb survival and bleb area. This was associated with a significant reduction in post-operative proliferation, inflammation and angiogenesis during the first post-operative days after surgery, and with a decrease in collagen deposition at later stages. Furthermore, inhibition of PlGF seemed to be more effective than anti-VEGF-R2 treatment in improving surgical outcome, possibly via its additional effect on inflammation. These results render PlGF an appealing target for ocular wound healing and point to potential therapeutic benefits of PlGF inhibition for the prevention of surgical failure.

Changes in visual acuity and intra-ocular pressure following bleb-related infection: the Japan Glaucoma Society Survey of Bleb-related Infection Report 2

PURPOSE

To identify changes in visual acuity and intra-ocular pressure (IOP) 12 months after the development of bleb-related infection.

METHODS

Data obtained from 146 eyes of 146 patients with bleb-related infection were analyzed as a part of the Japan Glaucoma Society Survey of Bleb-related Infection. Multiple logistic regression analysis was conducted to identify factors associated with poor prognosis in visual acuity and increased IOP and for being stage III.

RESULTS

The logMAR increased by a mean of 0.140, 0.440, 1.099 and 1.122 at 12 months postinfection for stage I, II, IIIa and IIIb infections, respectively. The logMAR was significantly worse at 6 and 12 months postinfection in stage IIIb (p = 0.002 and p = 0.003, respectively; Wilcoxon signed-rank test) and at 6 months postinfection in stage IIIa (p = 0.036). The IOP was significantly elevated following infection in both stage IIIa and stage IIIb (p = 0.028 and p = 0.008 at 6 and 12 months, respectively, for stage IIIa; p = 0.002 and p = 0.005 for stage IIIb). The multiple logistic regression analysis revealed that being stage III and positive culture were significant risk factors for poor outcome for visual acuity (Odds ratio: 9.26 and 6.29, respectively) and that being stage III was a prognostic factor for increased IOP (Odds ratio: 8.33). Pseudophakia or aphakia was significantly associated with stage III and stage IIIb infections (Odds ratio: 2.85 and 6.30).

CONCLUSIONS

Stage III bleb-related infection causes significant visual loss and IOP elevation within 12 months after development. Therefore, preventative measures should be taken, especially in cases that are pseudophakic or aphakic.

Management strategies to reduce risk of postoperative infections

Postoperative infections, although rare, are still of great concern to the ophthalmologist. The incidence of post-cataract endophthalmitis is low, with a range of .28 per 1,000 to 2.99 per 1000. In addition to intraoperative considerations such as poor wound construction, vitreous loss, topical anesthesia, and prolonged surgical time, other risk factors include preoperative factors such as a diseased ocular surface and systemic immunosuppression. Potential methods of reducing risk of endophthalmitis after anterior segment surgery are discussed and available literature is summarized.

Short term outcome of Ahmed glaucoma valve implantation in management of refractory glaucoma in a tertiary hospital in Oman

Background:

We present outcomes of Ahmed Glaucoma Valve (AGV) implantation in treating refractory glaucoma in a tertiary hospital in Oman. Refractory glaucoma was defined as previously failed conventional glaucoma surgery and an uncontrolled intraocular pressure (IOP) of more than 21 mm Hg despite treatment with three topical and/or oral therapy.

Materials and Methods:

This historical cohort study was conducted in 2010. Details of medical and surgical treatment were recorded. Ophthalmologists examined eyes and performed glaucoma surgeries using AGV. The best corrected distant vision, IOP, and glaucoma medications were prospectively reviewed on 1^st day, 1^st, 6^th, 12^th week postoperatively, and at the last follow up.

Result:

Glaucoma specialists examined and treated 40 eyes with refractory glaucoma of 39 patients (20 males + 19 females). Neo-vascular glaucoma was present in 23 eyes. Vision before surgery was <3/60 in 21 eyes. At 12 weeks, one eye had vision better than 6/12, seven eyes had vision 6/18 to 6/60, and eight eyes had vision 6/60 to 3/60. Mean IOP was reduced from 42.9 (SD 16) to 14.2 (SD 8) and 19.1 (SD 7.8) mmHg at one and 12 weeks after surgery, respectively. At 12 weeks, five (12.5%) eyes had IOP controlled without medication. In 33 (77.5%) eyes, pressure was controlled by using one or two eye drops. The mean number of preoperative anti-glaucoma medications (2.38; SD 1.1) was reduced compared to the mean number of postoperative medications (1.92; SD 0.9) at 12 weeks.

Conclusion:

We succeeded in reducing visual disabilities and the number of anti-glaucoma medications used to treat refractory glaucoma by AGV surgery.

A case involving an Ahmed™ glaucoma valve transferred from the vitreous into the anterior chamber of the eye with a silicone oil tamponade for the treatment of neovascular glaucoma

PURPOSE

To report the short-term efficacy and safety of the transfer of an Ahmed(™) glaucoma valve (AGV™) tube from the vitreous into the anterior chamber, in a patient with neovascular glaucoma who had undergone pars plana AGV(™) implantation and ultimately needed a silicone oil tamponade.

CASE

A 41-year-old male with proliferative diabetic retinopathy in both eyes was referred to us for treatment in December 2009. Although the patient previously underwent several surgeries, he ultimately lost vision in his right eye. His left eye suffered from neovascular glaucoma after undergoing a pars plana vitrectomy for tractional retinal detachment. After several vitreous and glaucoma surgeries, the patient underwent implantation of a pars plana AGV™. Postoperatively, although his intraocular pressure was stabilized at approximately 10 mmHg, he had repeated vitreous hemorrhage and hyphema without improvement. He ultimately underwent PPV with a silicone oil tamponade and at the same time, the AGV™ tube was pulled out from the vitreous and inserted into the anterior chamber in order to avoid complications caused by the silicone oil.

RESULTS

At 19 months postoperative, the patient's intraocular pressure had stabilized at 10 mmHg with no recurrence of vitreous hemorrhage and hyphema. Eventually, he lost vision in his left eye because of cerebral hemorrhage.

CONCLUSION

The findings show that insertion of a pars plana AGV™ tube into the anterior chamber in a patient undergoing a silicone oil tamponade is both effective and safe in the short-term.

Comparative study of trabeculectomy using single sutures versus releasable sutures

BACKGROUND

The purpose of this study was to compare the outcomes of trabeculectomy using single sutures or releasable sutures.

METHODS

This retrospective study analyzed the medical records of 61 patients who had undergone trabeculectomy using single sutures (n = 33, 54.1%) or releasable sutures (n = 28, 45.9%). The scleral flap was secured with a mean 3.9 (range 3-5) single sutures in 33 patients and with three releasable sutures in 28 patients. Primary outcomes were the success rate, based on intraocular pressure and medication usage, and the frequency of complications and post-surgical interventions. The criteria used to determine complete success were, first, intraocular pressure < 18 mmHg and, second, ≤21 mmHg and ≥20% intraocular pressure reduction without glaucoma medication.

RESULTS

All patients had an intraocular pressure ≤ 21 mmHg; 87.5% in the single suture group and 92.6% in the releasable suture group had an intraocular pressure < 18 mmHg at 24 months. There was a highly significant reduction in intraocular pressure to baseline values in both groups at the last visit. Applying the first criterion, complete success was achieved in 57.6% of patients with single sutures and 71.4% with releasable sutures, and based on the second criterion, 66.7% and 71.4%, respectively. No significant difference was found between the groups with regard to intraocular pressure, or success or complication rates.

CONCLUSION

The results of trabeculectomy using single sutures or releasable sutures are equivalent. Therefore, the choice of suture technique should be based on individual patient requirements and surgeon experience.

Use of viscoelastic substance in ophthalmic surgery - focus on sodium hyaluronate

Among viscoelastic substances, sodium hyaluronate has become the most popular for intraocular surgeries since the introduction of Healon^® (sodium hyaluronate 1%, 4 × 10⁶ daltons) in 1979. This review focuses on the recent development of a new generation of sodium hyaluronate agents with new rheologic properties and the relevant new techniques used in cataract, glaucoma, corneal, and vitreoretinal surgeries. The introduction of sodium hyaluronate agents with different rheologic properties has improved the safety and reliability of intraocular surgeries. Although there have been numerous studies reporting the effectiveness of viscoelastic substances in intraocular surgeries, rigorous validation by multi-center randomized control trials is lacking in many cases. At present, no single viscoelastic agent is most suitable to all of the various intraocular surgical techniques. Therefore, ophthalmologic surgeons should keep up with recent developments of viscoelastic agents and relevant surgical techniques for better patient care.

Review of results from the Tube Versus Trabeculectomy Study

PURPOSE OF REVIEW

The Tube Versus Trabeculectomy (TVT) Study is a multicenter randomized clinical trial comparing the safety and efficacy of tube-shunt surgery to trabeculectomy with mitomycin (MMC) in eyes with previous cataract and/or unsuccessful glaucoma surgery. This article reviews published results from the TVT Study.

RECENT FINDINGS

Tube-shunt surgery had a higher success rate than trabeculectomy with MMC during the first 3 years of follow-up. Trabeculectomy with MMC produced greater intraocular pressure (IOP) reduction in the early postoperative period compared with tube-shunt placement, but similar IOPs were observed after 3 months. Tube-shunt surgery was associated with greater use of adjunctive-medical therapy than trabeculectomy with MMC during the first 2 years of the study, but no difference in medication use was seen at 3 years. The incidence of postoperative complications was higher after trabeculectomy with MMC compared with tube-shunt surgery, but serious complications associated with vision loss and/or reoperation developed with similar frequency after both surgical procedures. No difference in the rate of vision loss was present following trabeculectomy with MMC and tube-shunt surgery after 3 years of follow-up. Cataract progression was common, but occurred with similar frequency with both procedures.

SUMMARY

Intermediate-term results of the TVT Study support the expanded use of tube shunts beyond refractory glaucomas. Tube-shunt surgery is an appropriate surgical option in patients who have undergone prior cataract and/or unsuccessful filtering surgery.

The medical and surgical treatment of glaucoma

BACKGROUND

Ongoing demographic changes in Europe are heightening the importance of adequate treatment for glaucoma, a disorder that is markedly more common in the elderly.

METHOD

A selective search for relevant literature, including Cochrane Reviews and the guidelines of the European Glaucoma Society, regarding the topical and surgical treatment of glaucoma.

RESULTS

It is recommended that the intraocular pressure (IOP) should be lowered by 20% to 50% from its baseline value, depending on the extent of already existing damage, the rate of progression, the baseline IOP, and the age of the patient. Topical monotherapy can lower the IOP by 15% to 30%. The success rate of filtration surgery has risen because of the intraoperative application of topical antimetabolites and currently ranges from 50% to 90%, depending on the study.

CONCLUSIONS

The goal of glaucoma treatment is to protect the patient from blindness and visual impairment while keeping the treatment-related decline in quality of life to a minimum. Any type of glaucoma treatment, be it medical or surgical, must further this aim in consideration of the situation of the individual patient.

Does titration of mitomycin C as an adjunct to trabeculectomy significantly influence the intraocular pressure outcome?

PURPOSE

To evaluate the benefit of titrating the concentration and exposure time of mitomycin C (MMC) as an adjunct to trabeculectomy.

METHODS

This report consists of a retrospective study and a review of the literature. In the study, consecutive glaucoma patients were evaluated who underwent trabeculectomy with adjunctive MMC that was titrated for concentration and exposure time, based on patient's risk factors for surgical failure. After minimum follow-up of 6 months, patients were divided into success (intraocular pressure 7-17 mmHg), hypertension (>17 mmHg) and hypotony (<7 mmHg) groups, which were compared with regard to MMC protocol and patient variables. The literature review included reports of trabeculectomy and adjunctive MMC with and without titration.

RESULTS

One hundred and fifty-five eyes of 155 patients were studied. There were no significant differences between the three outcome groups and MMC protocol (p > 0.05). The only significant patient variable was older age in the hypotony group (p = 0.009). The literature is conflicting regarding the value of titrating MMC as an adjunct in trabeculectomy.

CONCLUSION

The outcome of trabeculectomy with adjunctive MMC appears to represent a complex interaction of patient and surgical variables. While there is some support for a benefit of titrating MMC according to individual patient variables, there is inadequate evidence at the present time to claim superiority for any MMC protocol, with or without titration.

Aqueous dynamic and histological findings after deep sclerectomy with collagen implant in an animal model

AIM

The use of an animal model to study the aqueous dynamic and the histological findings after deep sclerectomy with (DSCI) and without collagen implant.

METHODS

Deep sclerectomy was performed on rabbits' eyes. Eyes were randomly assigned to receive collagen implants. Measurements of intraocular pressure (IOP) and aqueous outflow facility using the constant pressure method through cannulation of the anterior chamber were performed. The system was filled with BSS and cationised ferritin. Histological assessment of the operative site was performed. Sections were stained with haematoxylin and eosin and with Prussian blue. Aqueous drainage vessels were identified by the reaction between ferritin and Prussian blue. All eyes were coded so that the investigator was blind to the type of surgery until the evaluation was completed.

RESULTS

A significant decrease in IOP (p<0.05) was observed during the first 6 weeks after DSCI (mean IOP was 13.07 (2.95) mm Hg preoperatively and 9.08 (2.25) mm Hg at 6 weeks); DS without collagen implant revealed a significant decrease in IOP at weeks 4 and 8 after surgery (mean IOP 12.57 (3.52) mm Hg preoperatively, 9.45 (3.38) mm Hg at 4 weeks, and 9.22 (3.39) mm Hg at 8 weeks). Outflow facility was significantly increased throughout the 9 months of follow up in both DSCI and DS groups (p<0.05). The preoperative outflow facility (OF) was 0.15 (0.02) micro l/min/mm Hg. At 9 months, OF was 0.52 (0.28) microl/min/mm Hg and 0.46 (0.07) micro l/min/mm Hg for DSCI and DS respectively. Light microscopy studies showed the appearance of new aqueous drainage vessels in the sclera adjacent to the dissection site in DSCI and DS and the apparition of spindle cells lining the collagen implant in DSCI after 2 months.

CONCLUSION

A significant IOP decrease was observed during the first weeks after DSCI and DS. DS with or without collagen implant provided a significant increase in outflow facility throughout the 9 months of follow up. This might be partly explained by new drainage vessels in the sclera surrounding the operated site. Microscopic studies revealed the appearance of spindle cells lining the collagen implant in DSCI after 2 months.