Prospective study of surgical outcomes and bleb morphology using indocyanine green as a surgical dye in trabeculectomy with mitomycin C.

BACKGROUND: To investigate the effect of adding indocyanine green to mitomycin C in augmented trabeculectomy. DESIGN: A prospective, non-comparative interventional case series. PARTICIPANTS: A total of 37 eyes of 37 patients followed up for 1 year. METHODS: A solution containing 12.5 mg/mL of indocyanine green was added to mitomycin C, resulting in an mitomycin C concentration of 0.2-0.4 mg/mL, which was applied to bare sclera and Tenon's capsule for 3 min during trabeculectomy. MAIN OUTCOME MEASURES: Visual acuity, intraocular pressure, bleb morphology, Moorfields Bleb Grading System scores and complications. RESULTS: Indocyanine green could be visualized on clinical examination for all eyes on the first postoperative day. Mean intraocular pressure decreased from 22.9 ± 6.2 mmHg to 12.1 ± 4.4 mmHg postoperatively (P < 0.001) at 1 year. Thirty-four eyes (91.9%) achieved an intraocular pressure of less than 21 mmHg at final visit without additional topical intraocular pressure-lowering medications. Three eyes (8.1%) developed bleb failure and required Baerveldt device implantation. There were no cases of blebitis or late bleb leak. No adverse effects attributable to indocyanine green could be identified postoperatively. CONCLUSION: The addition of indocyanine green during trabeculectomy improves the visibility of antimetabolites intraoperatively and allows for the estimation of antimetabolite treatment area intraoperatively and postoperatively. It appears to have no adverse effect on surgical outcomes and complication rates, while improving safety of antimetabolite use.

Improved refractive outcome for ciliary sulcus-implanted intraocular lenses.

OBJECTIVE: To investigate the ideal correction of intraocular lens (IOL) power for sulcus implantation. DESIGN: Retrospective, comparative case series. PARTICIPANTS: The records of 679 patients undergoing cataract surgery from June 2007 to June 2008 were reviewed. INTERVENTION: Eyes in this series underwent phacoemulsification and IOL implantation with local anesthesia. Patients in our study population had their IOL power reduced by 0.5 or 1 diopter (D) from that calculated by the SRK-T formula for in-the-bag implantation. The IOL implanted was the foldable 3-piece acrylic Acrysof MA60AC (Alcon Laboratories Inc., Fort Worth, TX). MAIN OUTCOME MEASURES: In each case, the difference between actual spherical equivalent (SE) refraction and that predicted by biometry using the SRK-T formula was calculated. RESULTS: Posterior capsule tears requiring implantation of IOL in the ciliary sulcus occurred in 36 eyes. When comparing eyes in which the power was reduced by 0.5 D with those in which the reduction was 1.0 D, those with a power reduction of 1.0 D had significantly less unexpected error (0.49 vs. 1.01 D SE). After stratifying eyes by axial length (AL), we found higher unexpected refractive error in short eyes (<22 mm AL). Likewise, eyes with a predicted IOL power >25 D had a greater postoperative refractive error. CONCLUSIONS: This is the first comparative clinical review examining adjustment of power of the sulcus-implanted IOL. We found that the IOL power should be adjusted according to the measured AL and predicted IOL power. For patients with a predicted IOL power from 18 to 25 D, power should be reduced by at least 1 D; for lenses >25 D, power should be reduced by 1.5 to 2 D.

Comparison of standard trabeculectomy versus microtrabeculectomy as a surgical treatment for glaucoma: a randomized clinical trial.

BACKGROUND: To determine the effect of scleral flap size on the medium-term intraocular pressure control and complication rates after augmented trabeculectomy. DESIGN: Prospective randomized clinical trial. PARTICIPANTS: Glaucoma patients undergoing primary trabeculectomy. Exclusion criteria included previous ocular surgery apart from cataract surgery, secondary glaucoma and age under 18. METHODS: Patients were randomized to either standard trabeculectomy (4 × 4 mm scleral flap) or microtrabeculectomy (2 × 2 mm scleral flap), both with adjustable sutures and antimetabolites. Bleb needling was performed as required. Patients were evaluated at day 1, weeks 1, 3, 6 and months 3, 6, 12, 18 and 24 postoperatively. MAIN OUTCOME MEASURES: Vision, intraocular pressure, complications and failure (intraocular pressure ≥ 21 mmHg or not reduced by ≥20% from baseline, intraocular pressure ≤ 5 mmHg, repeat glaucoma surgery and no light perception vision). RESULTS: Forty-one patients were recruited; 20 had standard trabeculectomy, and 21 had microtrabeculectomy. At 2 years, the mean intraocular pressure and cumulative probability of failure was 12.4 ± 4.6 mmHg and 0.28 for standard trabeculectomy, and 11.5 ± 3.6 mmHg and 0.27 for microtrabeculectomy (P = 0.50 and 0.89, respectively). One patient in each group required Baerveldt device implantation. Vision reduced ≥2 Snellen lines in 15% in the standard trabeculectomy group and 25% in the microtrabeculectomy group, mainly from cataract (P = 0.48). CONCLUSION: Both trabeculectomy techniques achieved good intraocular pressure reduction and had similar complication rates. Scleral flap size had no significant effect on medium-term intraocular pressure control and complication profile.

In vivo fluorescence mode confocal microscopy of subepithelial tissues in glaucoma filtering blebs.

BACKGROUND AND OBJECTIVE: The miniaturization of confocal imaging technology has resulted in the development of a handheld confocal microscope probe capable of fluorescence mode imaging. Findings in the subepithelial tissues of glaucoma filtering blebs using this novel approach for proof of concept are described. PATIENTS AND METHODS: A fiberoptic confocal imaging probe using an illumination wavelength of 488 nm was applied to the bleb surface of 11 eyes after topical or subconjunctival administration of sodium fluorescein. The imaging plane was moved to the subepithelial region and multiple images from multiple bleb regions were captured at a resolution of 1,024 x 1,024 pixels per square inch. RESULTS: High-quality images of the bleb wall structure, vasculature, and superficial sclera were obtained and demonstrated subcellular detail. Lateral resolution was between 1 and 1.5 microm and axial resolution was approximately 30 microm. Identifiable structures in the failing blebs included vasculature (including individual erythrocytes, pericytes, and vascular endothelium); microcystic structures; and cells within the Tenon's tissue, some of which resembled fibroblasts. CONCLUSION: Fluorescence mode imaging of ocular subsurface detail is a viable and promising tool for assessment of wound healing and other processes in trabeculectomy blebs. The ability to image fluorophores creates the possibility of functional imaging.

The effect of scleral flap edge apposition on intraocular pressure control in experimental trabeculectomy.

BACKGROUND: To assess the contribution of scleral flap edge apposition to intraocular pressure (IOP) control in trabeculectomy, using a previously described and validated experimental model of guarded filtration surgery. MATERIALS AND METHODS: Twelve rectangular-flap trabeculectomy operations each with two apical adjustable sutures were performed on six donor human eyes connected to a constant flow infusion with real-time IOP monitoring. Three sizes of scleral flap were created: 4 x 4 mm, 16 mm(2) (n = 4), 3 x 3 mm, 9 mm(2) (n = 4) or 3 x 2 mm, 6 mm(2) (n = 4). Sutures were tied tightly to produce high aqueous outflow resistance, and equilibrium IOP established. The lateral and posterior edges of the scleral flap were removed, the sutures tightened again, and the new equilibrium IOP measured. RESULTS: Following flap closure and with intact flap edges, the mean absolute IOP for all flaps (n = 12) was 19.5 +/- 3.9 mm Hg (mean +/- SD, range 12.4-27 mm Hg) and following flap edge excision 18.7 +/- 4.4 mm Hg (range 5.6-27.9 mm Hg), demonstrating no significant difference between flaps with edge apposition compared with those without (P = 0.33). Mean relative IOP (% of baseline) was 68.4 +/- 12.1% (range 40.9-94%) with intact flap edges and 65.4 +/- 14.5% (range 18.5-97.2%) following flap edge excision (P = 0.31). Flaps measuring 4 x 4 mm and 3 x 3 mm behaved in a similar manner with minimal change in equilibrium IOP following excision of flap edges. CONCLUSIONS: In this experimental model, scleral flap edge apposition is not required for generating outflow resistance. Suture tension generated during tight flap closure produces apposition of the underside of the scleral trapdoor to the underlying bed, and it is this apposition, which determines IOP.

Acute angle closure after implantable contact lens insertion unresponsive to surgical peripheral iridectomy.

We present a case of acute angle closure that occurred after insertion of an implantable contact lens (ICL). The apparent papillary-block angle closure did not resolve after 2 patent iridotomies and a surgical iridectomy, but did respond to pupil dilation (not constriction). Ultrasound biomicroscopy revealed abnormally large and irregular ciliary processes that may have contributed to the unusual behavior of the ICL-iris complex. The condition resolved after the ICL was replaced by one with a smaller haptic diameter. Routine ultrasound biomicroscopic assessment of the ciliary body anatomy preoperatively and ICL haptic positioning postoperatively may identify risk factors that could predispose ICL patients to acute angle closure.

Information loss in 2 bleb grading systems.

PURPOSE: To assess the effectiveness of transferring descriptive information from bleb photographs to 2 recently described bleb grading systems: the Moorfields Bleb Grading System (MBGS) and the Indiana Bleb Appearance Grading Scale (IBAGS). METHODS: Two experienced observers graded 51 clinical bleb photographs with a wide range of appearances using both the MBGS and IBAGS bleb grading systems in random order. Grading scores from the 2 observers were averaged, and these numbers used by a third investigator, who did not view the original photographs, to generate 102 sketched representations of the blebs. The sketches were labeled randomly, and 1 month later presented individually in random order, to mask which grading system was used as source data for each drawing. MAIN OUTCOME MEASURES: The original graders then used an arbitrary 1-5 scale to rate congruity between sketches and photographs for vascularity and morphology features, and overall agreement of the bleb sketches. RESULTS: For both the IBAGS and MBGS, interobserver agreement between the Congruity Scores (CS) of the 2 masked graders was excellent, ranging between 92% and 98% for each parameter. Overall CS results were 3.2 (good-very good) for IBAGS and 4.1 (very good-excellent) for MBGS. Vascularity CS scores from IBAGS were 3.0 (good) and those from morphology agreement averaged 3.5 (good-very good). For the MBGS, the respective results were 3.9 (good-very good) and 4.1 (very good-excellent), respectively. Photographic quality (P=0.012) and presence of a limbus-based conjunctival flap scar (P=0.012) had an influence on CS scores from IBAGS but not from MBGS. CONCLUSIONS: Both the IBAGS and MBGS produced acceptable agreement ratings between the sketches derived from grading system data and the original bleb photographs. These grading systems seem to adequately represent the blebs that are being encoded, without significant information loss from the simplification and translation process. The MBGS tended to have higher CS, and may be less influenced by photograph quality and bleb type, suggesting that bleb photographs may be best encoded for statistical analysis in clinical studies using this system.

The influence of scleral flap position and dimensions on intraocular pressure control in experimental trabeculectomy.

PURPOSE: To assess the effect on intraocular pressure (IOP) of varying the length of the side incisions of the scleral flap during trabeculectomy. MATERIALS AND METHODS: Trabeculectomy operations were performed with adjustable sutures on 8 donor human eyes connected to a constant flow infusion with real-time IOP monitoring, using either a large (4 x 4 mm, 16 mm, n=8) or a small (3 x 2 mm, 6 mm, n=8) scleral flap. For each flap the side incisions began 1 mm behind the limbus and extended to the posterior edge of the flap. The side incisions were extended sequentially in 0.5-mm steps up to the limbus, then each flap dissected 1 mm further into clear cornea. RESULTS: Mean IOP after sclerostomy fashioning was 0.84 mm Hg (range 0 to 2.7 mm Hg). After flap closure, with side incisions extending to 1 mm behind the limbus, mean IOP was 21.6 mm Hg (79.5% of baseline) and 23.03 mm Hg (79.2% of baseline) for large and small flaps (P=0.26). In each size group, extending flap side incisions to the limbus produced a small nonsignificant fall in mean IOP, whereas flap extension 1 mm into clear cornea led to a significantly lower mean IOP relative to baseline of 43.2% (P<0.05) for large flaps and 35.4% for small flaps (P<0.01). CONCLUSIONS: Using this adjustable suture technique, IOP is well maintained for both flap sizes if the flap and side incisions do not extend beyond the limbus. Excessive forward dissection of a scleral flap into the clear cornea, anterior to the sclerostomy may result in increased aqueous outflow and lower IOP.

Ophthalmic herpes zoster in an 18-month-old child.

We present a case of herpes zoster ophthalmicus in an 18-month-old child. Early exposure to varicella zoster virus while being breast-fed appears to account for this clinical presentation. The incidence of herpes zoster in children younger than age 2 years is discussed.

Eccentric capsulorhexis and postoperative dysphotopsia following phacoemulsification.

We report a case of troublesome visual symptoms or dysphotopsia in a 68-year-old patient after right phacoemulsification and implantation of a 3-piece AcrySof(R) MA60BM acrylic intraocular lens (IOL) (Alcon) in the capsular bag. The patient described multiple horizontal streaks in dim lighting conditions with light sources in the right temporal visual field. The anterior capsulorhexis was eccentric, leaving the nasal optic edge and site of polypropylene haptic insertion uncovered by the semi-opaque anterior capsule and the probable source of the flare images. Miotic therapy was poorly tolerated and IOL exchange declined. The case illustrates the importance of creating a central capsulorhexis smaller than the IOL optic to reduce the risk photic phenomena and edge effect with square-edged IOLs.