Viscocanalostomy versus trabeculectomy for primary open angle glaucoma: 4-year prospective randomized clinical trial.

AIMS: The purpose of this randomized clinical trial was to compare the effectiveness and safety of viscocanalostomy (visco) with trabeculectomy (trab) in the management of primary open angle glaucoma (POAG). METHODS: Patients were randomized to have a viscocanalostomy (25 eyes) or a trabeculectomy (25 eyes) performed by one surgeon (TDM) and followed up prospectively. Patients were examined preoperatively, at day 1, day 3 if required, day 6, week 2 and thereafter as near as possible to 1, 3, 6, 12, 18, 24, 30, 36, 48, 54, and 60 months. We recorded intraocular pressure (IOP), presence or absence of any complications, presence and description of any bleb, visual acuity with glasses, and full examinations as routine to monitor any progression of the glaucoma. Bleb interventions including needling and antimetabolites were allowed and recorded in both groups. YAG laser goniopuncture was allowed in the viscocanalostomy group. RESULTS: Mean follow-up was 40 months (SD 15), with a range from 6 to 60 months. Forty-two percent (n=10) of the patients in the trabeculectomy group had a successful outcome (IOP<18 mm Hg with no treatment) at last follow-up visit, compared to 21% (n=5) in the viscocanalostomy group. IOP was lower in the trab group with differences in IOP being statistically significant at month 12 (P=<0.001), 24 (P=<0.001), 30 (P=0.030), 36 (P=<0.001), and 48 (P=0.018). The trabeculectomy group required less postoperative topical IOP-lowering medication (P=0.011). CONCLUSION: In this study, we found trabeculectomy to be more effective at lowering IOP than viscocanalostomy in POAG patients.

Phacotrabeculectomy without peripheral iridectomy.

BACKGROUND AND OBJECTIVE: Peripheral iridectomy has been a long established part of glaucoma drainage surgery. This series examines the potential to dispense with iridectomy when trabeculectomy is combined with modern small-incision cataract surgery. PATIENTS AND METHODS: Twenty-five unselected consecutive patients underwent a standardized phacotrabeculectomy by a single surgeon. Outcome measures included visual acuity, intraocular pressure control, and complication rates. Mean follow-up was 12.2 months. RESULTS: There were no complications related to lack of peripheral iridectomy. Intraocular pressure was reduced from a mean of 23.4 mm Hg (SD 5.1) to 15.9 (SD 3.8) at 6 months, and 15.4 (SD 3.5) at 12.2 months. There were 2 relative failures of surgery whose IOP reached preoperative targets with additional medical treatment. Best Snellen acuity improved by a mean of 1.5 lines. CONCLUSIONS: Phacotrabeculectomy without peripheral iridectomy appears to be safe, although we consider that a corneal fistula and careful control of postoperative overdrainage is necessary to allow this. The success rate and lack of complications is good by comparison with other series. This could be related to the absence of release of factors influencing healing at the time of an iridectomy.

Phacotrabeculectomy with "smile" incision, punch, and single releasable suture.

BACKGROUND AND OBJECTIVE: To describe and prospectively evaluate a technique of phacotrabeculectomy consisting of a "smile" wound, corneal punch, and tight closure of the scleral flap with a single releasable suture. PATIENTS AND METHODS: A cohort of 25 patients underwent this procedure performed by a single surgeon. The surgical technique is described and the first year of follow-up is evaluated. RESULTS: Mean intraocular pressure (IOP) was 25.4 mm Hg preoperatively and 16.2 mm Hg at a mean follow-up of 10.2 months (a fall of 36%). Incidence of immediate postoperative complications was low, especially those related to hypotony (wound leak, shallow anterior chamber, fibrinous uveitis). There was a 50% incidence of postoperative IOP spikes of greater than 26 mm Hg. Three cases were deemed partial failures at 1 year (IOP < 21 mm Hg on medical treatment), and three cases were complete failures (IOP > 21 mm Hg or further surgery required). CONCLUSION: The tight scleral flap and routine release of the releasable suture on the third postoperative day reduce immediate postoperative complications compared with other studies, with the exception of IOP spikes. The lack of aqueous flow in the immediate postoperative phase may be a factor in the failure rate, which is higher than expected.

Heparinised intraocular infusion and bacterial contamination in cataract surgery.

BACKGROUND/AIMS: Heparin in solution reduces bacterial adhesion to intraocular lenses and a lower incidence of postoperative endophthalmitis has been reported with the use of heparin coated lenses. The safety of adding low molecular weight heparin to the infusion fluid during routine cataract surgery was investigated. Any direct antibacterial effect was looked for by culturing anterior chamber fluid samples taken at the completion of surgery. METHODS: A randomised, double blind, controlled study of 111 patients undergoing routine cataract surgery. Low molecular weight heparin at a concentration of 5 IU/ml was added to the infusion fluid in the trial patients. Samples from the anterior chamber taken at completion of surgery were cultured. Twenty nine samples of sterile infusion fluid were also cultured as further controls. RESULTS: No complications were found in either group, and no difference in observed postoperative inflammation in each group. In the heparinised group (n = 55) bacterial contamination was found in 31% of samples, compared with 27% in the no heparin group (n = 56) (no significant difference). CONCLUSIONS: There appears to be no direct antibacterial effect of heparin, and other possible mechanisms of action are discussed. Heparin avoids many of the drawbacks of traditional antibiotic prophylaxis and may have the potential to be a safe and effective addition to endophthalmitis prevention.

Randomised trial of topical versus sub-Tenon's local anaesthesia for small-incision cataract surgery.

Fifty unselected patients undergoing routine cataract surgery were randomised to receive either topical or sub-Tenon's local anaesthesia with 2% prilocaine administered by a blunt cannula. Visual analogue scales were used to assess pain during administration of sub-Tenon's anaesthetic and pain during surgery, and any complications were noted. Sub-Tenon's anaesthesia proved to be entirely comfortable to administer, and allowed for a statistically significantly more pain-free operation, at the expense of some residual eye movement and an inevitable subconjunctival haemorrhage. Both techniques compared well with other studies assessing periorbital or retro-orbital injections, and both have significant safety advantages which are discussed in the context of the joint Royal Colleges report on ophthalmic anaesthesia. It is suggested that a combination of one or other technique could safely cover all requirements for intraocular surgery under local anaesthesia.

Anterior chamber aspirate cultures in small incision cataract surgery.

BACKGROUND: Anterior chamber aspirates on completion of extracapsular cataract surgery contain significant numbers of organisms, particularly coagulase negative staphylococci, an important cause of endophthalmitis. METHODS: Culture rates were compared in 50 patients after phacoemulsification surgery, which allows the possible benefits of a small, self sealing wound and maintenance of positive intraocular pressure, with a similar number of extracapsular cases. RESULTS: A culture positive rate of 20% and 24% respectively was found, an insignificant difference. CONCLUSION: Small incision surgery has no proved advantage over extracapsular surgery in terms of reducing the intraoperative bacterial inoculum. The significance of this result in terms of causation of endophthalmitis is discussed.

The introduction of a formal paediatric screening programme into an army general practice.

The establishment of a formal paediatric screening programme in an Army group practice in West Germany is described. In the first year, three hundred and fifteen children were seen and thirty two abnormalities were recorded. This 'pick-up' rate of approximately ten per cent dysfunction accords well with previously published work. The scheme has proved successful and popular. It has improved primary health care team work, health education and patient satisfaction within the practice. It is suggested as model for wider introduction into Army general practice.