Viscocanalostomy vs. trabeculectomy

Pseudoexfoliation Syndrome and Pseudoexfoliation Glaucoma: A Review of the Literature with Updates on Surgical Management

Pseudoexfoliation syndrome (PES) is a systemic disorder caused by progressive accumulation of extracellular material over various tissues. PES usually determines increased intraocular pressure, changes in the anatomical aspects of the optic nerve, and visual field alterations leading to the diagnosis of pseudoexfoliation glaucoma (PEG). Use of topical medical treatment usually leads to poor results in terms of long-term follow-up but many surgical techniques, such as Argon Laser or Selective Laser Trabeculoplasty, have been proposed for the management of PEG affected patients. The present paper is a review on the pseudoexfoliation syndrome and pseudoexfoliation glaucoma with an update on surgical management.

Combined cataract and glaucoma surgery with mitomycin C: phacoemulsification-trabeculectomy compared to phacoemulsification-deep sclerectomy

AIMS

To compare outcomes of phacoemulsification combined with trabeculectomy (PT) or deep sclerectomy (PDS) with intraoperative mitomycin C (MMC) application.

METHODS

Non-randomised, consecutive, retrospective comparative study. 97 eyes of 97 patients (59 PDS, 38 PT) undergoing combined surgery with intraoperative MMC (0.1-0.4 mg/ml for 1-3 minutes) were identified for inclusion in the study.

RESULTS

The probability of maintaining intraocular pressure (IOP) below 19 mm Hg and 15 mm Hg, with a 30% drop from preoperative IOP and without additional medication, 1 year after surgery were 77.6% (95% CI: 67 to 90) and 71.5% (60 to 85) for the PDS group and 89.5% (80 to 99) and 89.5 (80 to 99) for the PT group, respectively, and these differences were not statistically significant (p>0.05, log rank test). After excluding ocular co-morbidity no differences were observed in the improvement of visual acuity between the two groups. There were no major differences in the complication rates except that delayed bleb leaks were seen in seven eyes (18.4%) of the PT group (p = 0.004).

CONCLUSION

In this study, no statistically significant difference was found in the IOP and visual outcomes between PDS and PT. A significantly higher frequency of late bleb leaks after PT was observed.

Deep sclerectomy augmented with mitomycin C

AIMS

To investigate the comparative efficacy and safety of deep sclerectomy with and without intraoperative mitomycin C (MMC) application for lowering the intraocular pressure (IOP).

METHODS

A total of 71 eyes of 71 consecutive patients who had routine deep sclerectomy (DS), nonaugmented (DS-noMMC) or with mitomycin C (DS-MMC) augmentation (0.2 mg/ml for 2 min) and follow-up of 4 months or more were identified from an ongoing prospective database on glaucoma surgery. Indications for MMC use were the presence of risk factors for subconjunctival scarring and low target IOPs. MMC 0.2 mg/ml was applied in the sub-Tenons space for 2 min.

RESULTS

There were 19 eyes in the DS-noMMC group and 52 eyes in the DS-MMC group. In 11 eyes (15.5%), the procedure was complicated by intraoperative perforation of the trabeculo-Descemet's window. Eyes in the DS-MMC group had significantly lower IOPs (MANOVA, P = 0.04). Kaplan-Meier survival curve analysis showed that the probability of maintaining IOP below target IOP level, below 18 mmHg and below 14 mmHg at 1 year was 51, 67, and 35% for the DS-noMMC group and 80, 86, and 74% for the DS-MMC group. The survival rates of the DS-MMC group were not statistically significant (P = 0.06) when the success criterion was maintaining an IOP less than 18 mmHg but were significant for the other criteria, namely IOP less than target levels (P = 0.03) and less than 14 mmHg (P = 0.03). Nd:YAG goniopuncture to lower IOP to target levels was done more frequently in the DS-noMMC group (13 eyes, 81%) than the DS-MMC group (20 eyes, 45%) and this difference was significant (P = 0.03). The prevalence of avascular areas within filtration blebs and transconjunctival oozing of aqueous was significantly higher in the DS-MMC group (P < 0.01).

CONCLUSIONS

The use of intraoperative MMC during deep sclerectomy has a significant effect on the postoperative IOP and increases the probability of achieving target IOPs. However, our current technique of MMC application is associated with a higher incidence of avascular blebs and transconjunctival oozing.

Concave trabeculo-Descemet's membrane as an early sign of viscocanalostomy failure

PURPOSE

To correlate trabeculo-Descemet's membrane (TDM) changes with a late rise in intraocular pressure (IOP) in patients with successful viscocanalostomy.

SETTING

Consultores Oftalmológicos, Hospital Oftalmológico Santa Lucía, and Centro de Estudios Médicos e Investigación, Buenos Aires, Argentina.

METHODS

Patients who had a viscocanalostomy between July 1998 and September 2001 were retrospectively studied. Gonioscopy was performed in all patients. A subgroup of patients who had a late increase in IOP and were successfully treated with neodymium:YAG (Nd:YAG) laser goniopuncture were studied to correlate gonioscopic findings. Ultrasound biomicroscopy was performed in 10 cases. Intraocular pressure measurements were taken before viscocanalostomy and before and after Nd:YAG treatment.

RESULTS

Sixty-eight eyes of 48 patients had a viscocanalostomy to control IOP. Twenty-six eyes had a late increase in IOP and were successfully treated with Nd:YAG laser goniopuncture. Before goniopuncture, 17 eyes (65.30%) had a concave TDM. The mean IOP in these patients increased from 14.27 mm Hg to 18.73 mm Hg (range 14 to 27 mm Hg). Goniopuncture was performed a mean of 10.7 months (range 1 to 36 months) after surgery. After Nd:YAG treatment, the TDM was flat in all patients who had a concave TDM before treatment. At the last examination, the mean IOP was 13.8 mm Hg, a mean decrease of 52.24% from the baseline preoperative IOP; 61.5% of eyes had a final IOP of 14.0 mm Hg or lower.

CONCLUSIONS

A concave TDM was associated with a late IOP rise. The TDM was flat after laser goniopuncture and normalization of IOP.