Oculoplastic aspects of ocular surface disease and their management.

The normal structure and function of the eyelids, eyelashes, conjunctival fornices, and lacrimal system are essential for the health of the ocular surface, and abnormalities of these structures accompany many cases of ocular surface disease. We describe the role of oculoplastic intervention in the context of ocular surface disease, focusing on blink disorders, lagophthalmos, entropion, lid scarring and keratinization, trichiasis, and punctal and lacrimal sac disease.

Corneal melting in rheumatoid arthritis patients treated with a tectonic reinforcing corneolimbal graft: an interventional case series.

PURPOSE: Corneal melting with perforation is a severe ophthalmic complication of autoimmune disorders such as rheumatoid arthritis. It requires urgent medical management in order to maintain the integrity of the globe and preserve vision. Treating this complication by penetrating keratoplasty is problematic due to the high rate of recurrence of corneal melting as well as other complications. We describe the use of a tectonic fresh-tissue corneolimbal covering graft. METHODS: An interventional case series including three patients that presented to our tertiary center between 2000 and 2015 with corneal melting and perforation, secondary to rheumatoid arthritis. Emergency surgery included suturing of a 13.00- to 13.50-mm full-thickness fresh-tissue corneolimbal covering graft to the patient's posterior limbal zone. RESULTS: The corneolimbal graft maintained the integrity of the cornea in all cases, by sealing the perforation and promoting the creation of a fibrovascular scar at the area of corneal melting. There were no complications, recurrences of host corneal melting, or perforation during the follow-up period. CONCLUSION: Fresh-tissue full-thickness corneolimbal grafts may be used to cover emergency corneal melting and perforations secondary to rheumatoid arthritis.

Scleral Cross-linking Using Riboflavin and Ultraviolet-A Radiation for Prevention of Axial Myopia in a Rabbit Model.

Myopic individuals, especially those with severe myopia, are at higher-than-normal risk of cataract, glaucoma, retinal detachment and chorioretinal abnormalities. In addition, pathological myopia is a common irreversible cause of visual impairment and blindness. Our study demonstrates the effect of scleral crosslinking using riboflavin and ultraviolet-A radiation on the development of axial myopia in a rabbit model. The axial length of the eyeball was measured by A-scan ultrasound in New Zealand white rabbits aged 13 days (male and female). The eye then underwent 360° conjunctival peritomy with scleral crosslinking, followed by tarsorrhaphy. Axial elongation was induced in 13 day-old New Zealand rabbits by suturing their right eye eyelids (tarsorrhaphy). The eyes were divided into quadrants, and every quadrant had two scleral irradiation zones, each with an area of 0.2 cm² and a radius of 4 mm. Crosslinking was performed by dropping 0.1% dextran-free riboflavin-5-phosphate onto the irradiation zones 20 sec before ultraviolet-A irradiation and every 20 sec during the 200 sec irradiation time. UVA radiation (370 nm) was applied perpendicular to the sclera at 57 mW/cm² (total UVA light dose, 57 J/cm²). Tarsorrhaphies were removed on day 55, followed by repeated axial length measurements. This study demonstrates that scleral crosslinking with riboflavin and ultraviolet-A radiation effectively prevents occlusion-induced axial elongation in a rabbit model.

Scleral cross-linking using riboflavin and ultraviolet-a radiation for prevention of progressive myopia in a rabbit model.

Our study demonstrates the effect of scleral cross-linking using riboflavin and ultraviolet-A radiation on the development of axial myopia in a rabbit model. Axial length of the eyeball was measured by A-scan ultrasound in 22 New Zealand white rabbits aged 13 days. The right eyes then underwent 360-degree conjunctival peritomy with (experimental group, n = 11) or without (control group, n = 11) scleral cross-linking, followed by tarsorrhaphy. The left eyes served as a control eye. In the experimental group, the right eyeballs were divided into quadrants, and every quadrant had either 2 (n = 8) or 6 (n = 3) scleral irradiation zones, each with an area of 0.2 cm² and radius of 4 mm. Cross-linking was performed by dropping 0.1% dextran-free riboflavin-5-phosphate onto the irradiation zones at 20 s before ultraviolet-A irradiation and every 20 s during the 200-s irradiation time. UVA radiation (370 nm) was applied perpendicular to the sclera at 57 mW/cm² (total UVA light dose, 57 J/cm²). Tarsorrhaphies were removed on day 55, followed by repeated axial-length measurement. In the control group, mean axial length in the right eyes increased from 10.50 ± 0.67 mm at baseline to 15.69 ± 0.39 mm 55 days later, for a mean change of 5.19 ± 0.85 mm. In the experimental group, corresponding values were 10.68 ± 0.74 mm and 14.29 ± 0.3 mm, for a mean change of 3.61 ± 0.76 mm. The between-group difference in the change in mean axial length was statistically significant (p < 0.001, Mann-Whitney nonparametric test). The present manuscript demonstrates that scleral cross-linking with riboflavin and ultraviolet-A radiation effectively prevents occlusion-induced axial elongation in a rabbit model.

Outcome of "mushroom" pattern femtosecond laser-assisted keratoplasty versus conventional penetrating keratoplasty in patients with keratoconus.

PURPOSE: The aim of this study was to compare the outcomes of "mushroom" femtosecond laser-enabled keratoplasty (M-FLEK) with those of conventional penetrating keratoplasty (PKP) in eyes with keratoconus. The femtosecond laser-enabled "mushroom" pattern keratoplasty technique results in less postoperative astigmatism and higher endothelial cell counts compared with conventional PKP in patients with keratoconus. METHODS: This was a nonrandomized retrospective, single private center clinical study. Between March 2010 and April 2012, 26 eyes underwent M-FLEK and 33 eyes underwent conventional PKP. Data on preoperative and postoperative manifest refraction, uncorrected visual acuity and best-corrected visual acuity (BCVA), endothelial cell counts, vector analysis, and complications were retrieved and analyzed. RESULTS: At 12 months of follow-up, the mean logMAR BCVA was 0.31 ± 0.55 in the M-FLEK group and 0.32 ± 0.21 in the PKP group (P = 0.91). The mean spherical equivalent was similar between the groups. The mean manifest cylinder was significantly lower in the M-FLEK group (-2.84 ± 1.08 diopters) than in the PKP group (-3.93 ± 2.26 diopters; P = 0.03). There was a smaller mean endothelial cell loss in the M-FLEK group compared with the PKP group (32.1% vs 38.7%, respectively, P = 0.17) 1 year postoperatively. The complication rates were similar for both groups. CONCLUSIONS: M-FLEK appears to be a safe procedure that results in less astigmatism and a trend toward higher endothelial cell counts compared with conventional PKP, with similar postoperative BCVA.

Intracameral recombinant tissue plasminogen activator (r-tPA) for refractory toxic anterior segment syndrome.

AIMS: To investigate the therapeutic effect of recombinant tissue plasminogen activator (r-tPA) in patients with refractory toxic anterior chamber segment syndrome after cataract surgery with posterior chamber intraocular lens implantation. METHODS: This prospective cohort study was performed from May 2010 to November 2011 at a tertiary university-based medical centre. Forty patients (40 eyes) with an anterior chamber fibrin reaction after cataract surgery were treated with intracameral injection of r-tPA (25 µg/0.1 mL) following failure to respond to conventional treatment with intensive topical and subconjunctival steroids. Outcome measures were best-corrected visual acuity, clearance/recurrence of the fibrin reaction and complications. Corneal endothelial cell counts were evaluated before and after r-tPA injection (n=6). RESULTS: Intracameral r-tPA injection was administered 10-49 days after cataract surgery; mean was 20.3±9.6 days after surgery. At 1 day after treatment, complete clearance of the fibrin reaction was observed in 32 patients (80%) and partial clearance in 8 (20%). At the 1-month evaluation, the reaction had completely resolved in 95% of patients. Mean visual acuity improved from 0.61±0.38 logMAR before treatment to 0.45±0.37 logMAR 1 month later (p=0.06). There were no statistically significant differences in improvement in visual acuity and fibrinolysis rate by time of r-tPA injection after surgery (10-15 days, n=16 vs 16-49 days, n=24). There were no cases of increased intraocular pressure or endophthalmitis following the procedure. CONCLUSIONS: Intracameral injection of 25 µg r-tPA is safe and effective for the treatment of refractory fibrin reaction after cataract surgery.

Corneal graft failure following Nd:YAG laser membranotomy for inadvertent retained descemet's membrane after penetrating keratoplasty.

Retained Descemet's membrane (DM) following penetrating keratoplasty (PKP) is a rare finding that may reduce visual acuity following opacification or endanger the graft endothelium. The association between Nd:YAG laser membranotomy and corneal graft failure is reported. Five of 1,350 patients (0.37%) undergoing PKP for pseudophakic bullous keratopathy or graft failure between 1986 and 2008 presented with inadvertent retained DM located close to the graft endothelium. The membrane opacified within 3 to 4 months, reducing the patients' vision. Nd:YAG laser membranotomy was performed using low energy and few pulses. Patients' visual acuity improved from 6/40 to 6/90 before treatment to 6/15(-) to 6/20 at 2 weeks following membranotomy. However, the corneal graft decompensated within 6 to 8 weeks following this procedure, necessitating repeat PKP, with removal of the retained DM. Nd:YAG laser membranotomy may lead to corneal graft failure due to shockwave damage created by the laser pulses, focused near the endothelial surface.

Simultaneous wavefront-guided photorefractive keratectomy and corneal collagen crosslinking after intrastromal corneal ring segment implantation for keratoconus.

PURPOSE: To study the results of simultaneous photorefractive keratectomy (PRK) and corneal collagen crosslinking (CXL) in keratoconus after previous intrastromal corneal ring segment (ICRS) implantation. SETTING: Enaim Laser Center, Jerusalem, Israel. DESIGN: Case series. METHODS: This study comprised patients with moderate keratoconus who had previous Intacs ICRS implantation with the Intralase laser at least 6 months before PRK-CXL. Wavefront-guided PRK and ultraviolet-A CXL were performed simultaneously. Refraction, uncorrected (UDVA) and corrected (CDVA) distance visual acuities, keratometry (K) values, endothelial cell count (ECC), pachymetry, corneal resistance factor (CRF), and corneal hysteresis (CH) were assessed 3, 6, and 12 months postoperatively. RESULTS: Twelve months after PRK-CXL, the mean decimal UDVA improved significantly from 0.20 ± 0.12 (SD) to 0.55 ± 0.15 (P<.01). The mean decimal CDVA improved from 0.58 ± 0.13 to 0.77 ± 0.17 (P=.01). The mean cylinder decreased from -3.60 ± 1.70 to -1.30 ± 1.10 diopters (D) (P<.001). The mean apex K decreased from 50.91 ± 5.50 D to 46.61 ± 4.52 D (P<.005). The other corneal parameters did not change significantly after treatment. No significant difference was found between the 6-month and 12-month results. No patient lost lines of CDVA. Mild haze remained in 11.1% of eyes 12 months after treatment. CONCLUSIONS: Simultaneous wavefront-guided PRK and CXL for keratoconus after ICRS implantation was safe and effective. It significantly improved the UDVA, CDVA, and central K value, and consequently the visual function, of patients with moderate keratoconus.

Endophthalmitis and wound dehiscence following late removal of penetrating keratoplasty sutures.

BACKGROUND AND OBJECTIVE: The patient characteristics, risk factors, and outcome of penetrating keratoplasty (PK) wound dehiscence following late suture removal. PATIENTS AND METHODS: Retrospective review of 207 cases of PK performed between 2005 and 2007 in Beilinson Hospital, Israel. RESULTS: Analysis of 207 patients who underwent PK revealed 4 cases (an incidence of 1.93%) that developed spontaneous wound dehiscence with severe endophthalmitis following late suture removal. Mean time from transplantation to suture removal was 22.18 months (range: 18 to 26 months). The time from suture removal to endophthalmitis was on average 2.25 weeks. All patients underwent vitrectomy with injection of intraocular antibiotics. The causative microorganism was found to be Streptococcus species in three patients and Staphylococcus epidermidis in one patient. One patient retained a clear corneal graft, another patient is scheduled for repeat PK, and the last two patients lost sight (50%). CONCLUSION: Endophthalmitis and wound dehiscence following late suture removal after PK are rare complications, but the end result can be devastating to the transplanted eye when they do occur. Careful monitoring and close follow-up can aid in early identification and treatment of such complications and may prevent loss of sight. Newer methods of corneal transplantation, such as Descemet's stripping automated endothelial keratoplasty or Descemet's membrane endothelial keratoplasty, should be considered as a better alternative to PK whenever the case qualifies as such.

Consecutive appearance of corneal subepithelial infiltrates after intravitreous bevacizumab injections.

PURPOSE: To report a case of corneal subepithelial infiltrates appearing after intravitreous bevacizumab injections. METHODS: A review of the patient's history and clinical examination findings in a patient who had epidemic keratoconjunctivitis more then 20 years before treatment with bevacizumab for age-related macular degeneration. RESULTS: After the third and fourth bevacizumab injections, the patient presented with unilateral corneal subepithelial infiltrates. The infiltrates were accompanied by mild anterior chamber reaction and resolved with topical steroid treatment. CONCLUSIONS: Treatment with intravitreous bevacizumab may precipitate an immune response leading to the appearance of corneal subepithelial infiltrates.

Effect of subconjunctival and intraocular bevacizumab injections on corneal neovascularization in a mouse model.

PURPOSE: This study sought to evaluate the efficacy of bevacizumab (Avastin), an anti-VEGF agent, in the reduction of corneal neovascularization in a rodent model, and compare between the effect of intraocular and subconjunctival injection. METHODS: Corneal neovascularization was induced by application of a mixture of 75% silver nitrate and 25% potassium nitrate to the corneal center of the right eye of 125 mice. Immediately thereafter, 75 eyes were treated with subconjunctival, anterior chamber, or intravitreal injection of bevacizumab. The remaining mice served as a control. The groups were compared at different postoperative time points for percentage area of neovascularization evaluated by digital photos, the presence of corneal stromal vascular endothelial cells studied by immunohistochemical staining, and VEGF levels measured by real-time PCR. RESULTS: In the untreated eyes, percentage area of neovascularization increased from 11.3 +/- 7% on day 2 to 20 +/- 8.9% on day 4, 47 +/- 25.4% on day 8, and 51 +/- 24.7% on day 10. The percentage area of neovascularization following subconjunctival injection was 7 +/- 2.9% on day 2, 15.7 +/- 6% on day 4, 32.2 +/- 15.2% on day 8, and 39.7 +/- 14.5% on day 10. The percentage area of neovascularization following anterior chamber injection was 14.4 +/- 3% on day 2, 16.5 +/- 6.3% on day 4, 26.3 +/- 6.5% on day 8, and 19.8 +/- 1.2% on day 10. The percentage area of neovascularization following intravitreal injection was 11 +/- 2.5% on day 2, 14.7 +/- 5% on day 4, 23.5 +/- 6.5% on day 8, and 24.2 +/- 14.9% on day 10. CONCLUSIONS: Bevacizumab injections partially inhibit the growth of corneal neovascularization induced by acute chemical injury in a mouse model. The intraocular routes of injection were found to be the most effective, and the subconjunctival route of injection yielded the earliest peak response.

Effect of intravitreal bevacizumab (avastin) on the growing rabbit eye.

PURPOSE: To study the effect of intravitreal bevacizumab (Avastin) on the structure and growth of the young rabbit eye. MATERIALS AND METHODS: Twelve 6-week-old rabbits underwent intravitreal injection of bevacizumab (1.25 mg/0.05 ml) in one eye and no injection in the other (study group). Six additional rabbits served as controls. Slit lamp examination, fundus evaluation, and measurements of corneal power, central corneal thickness, corneal astigmatism, and axial length were performed before treatment and 1, 2, and 3 months after. At 3 months, the rabbits were sacrificed for histological study. RESULTS: Within the study group, there were no significant differences in clinical parameters between the bevacizumab-treated and fellow eyes at any timepoint or overall. The estimated confidence intervals extended to about one standard deviation of their respective values. Comparison of the injected eyes in the study group with the uninjected eyes in the control group yielded similar findings. There were no between-group differences in ocular growth and no abnormalities of the anterior and posterior segments or the retina and retinal vasculature. CONCLUSIONS: Intravitreal bevacizumab apparently has no adverse effect on the growth and development of the young rabbit eye, in a biologically or statistically significant way.

Fresh-tissue corneolimbal covering graft for large corneal perforation following childhood trachoma.

BACKGROUND AND OBJECTIVE: When corneal perforation develops in patients with severe ocular surface disease and limbal stem cell deficiency following childhood trachoma infection, penetrating keratoplasty is doomed to fail. To overcome this problem, the use of a fresh-tissue corneolimbal covering graft is described. PATIENTS AND METHODS: Retrospective interventional case series of four patients who presented to a tertiary center from 2003 to 2005 with a large corneal perforation due to ocular surface disease. Emergency surgery consisted of suturing a fresh-tissue corneolimbal covering graft to the patients' peripheral sclera. RESULTS: The corneolimbal graft became partially incorporated into the perforated cornea, which healed by scar tissue, after a few months. The ocular epithelial surface improved considerably. There was no recurrence of corneal perforation during the follow-up period of 1 to 3 years. CONCLUSION: Fresh-tissue corneolimbal covering graft was found to be a useful technique for saving the integrity of the eye in cases of a large corneal perforation in patients with severe ocular surface disease, such as in childhood trachoma.

Wavefront-guided LASIK for myopia with the Technolas 217z: results at 3 years.

PURPOSE: To evaluate the clinical outcome of wavefront-guided LASIK in patients with low to high myopia. METHODS: The study included 316 eyes of 158 patients; 172 eyes with low to moderate myopia (< or = 6.00 diopters [D]) and 144 eyes with high myopia (> or = 6.25 D). Preoperative wavefront analysis was performed with the Hartmann-Shack aberrometer, and LASIK was done with the Technolas 217z excimer laser. Follow-up was 36 months. Safety, efficacy, predictability, stability, and complications were compared between groups. RESULTS: Mean preoperative spherical equivalent refraction (SE) was -6.50 +/- 7.72 D (range: -1.50 to -16.00 D) in the entire study group, -4.91 +/- 1.38 D in the low to moderate myopia group, and -9.41 +/- 2.51 D in the high myopia group. At 36 months, 222 (70%) eyes showed no change in best spectacle-corrected visual acuity and 67 (21%) eyes gained > or = 1 line. In the low to moderate myopia group, SE of +/- 0.50 D was achieved by 85% of eyes and +/- 1.00 D by 97%, and 65% and 80%, respectively, in the high myopia group. Undercorrection > 0.50 D was observed in 25% (36 eyes) of the high myopia group and 5% (8 eyes) of the low to moderate myopia group. All eyes showed significant reduction in spherical aberration (Z4,0) at 12 months postoperatively with no complications except diffuse lamellar keratitis in 2 eyes (1 eye in each group). CONCLUSIONS: Wavefront-guided LASIK is an efficient refractive surgery technique for patients with low to moderate myopia. Higher degrees of myopia may be subject to under- and overcorrection.

Refractive eye surgery in treating functional amblyopia in children.

PURPOSE: While excimer laser refractive surgery is recommended and highly successful for correcting refractive errors in adults, its use in children has not been extensively exercised or studied. We report our experience treating children with amblyopia due to high anisometropia, high astigmatism, high myopia and with associated developmental delay. SETTING: Review of patient records of our refractive clinic. METHODS: A retrospective review was made of all 11 children with stable refractive errors who were unsuccessfully treated non-surgically and then underwent corneal refractive surgery and in one case, lenticular surgery. Seven had high myopic anisometropia, 2 had high astigmatism, and two had high myopia--one with Down's Syndrome and one with agenesis of the corpus callosum. RESULTS: The surgical refractive treatment eliminated or reduced the anisometropia, reduced the astigmatic error, improved vision and improved the daily function of the children with developmental delay. There were no complications or untoward results. CONCLUSIONS: Refractive surgery is safe and effective in treating children with high myopic anisometropia, high astigmatism, high myopia and developmental delay due to the resulting poor vision. Surgery can improve visual acuity in amblyopia not responding to routine treatment by correcting the refractive error and refractive aberrations.

Wavefront-supported photorefractive keratectomy with the Bausch & Lomb Zyoptix in patients with myopic astigmatism and suspected keratoconus.

PURPOSE: To evaluate the safety, efficacy, and visual outcome of wavefront-supported photorefractive keratectomy (PRK) for the correction of myopia and myopic astigmatism in patients with suspected keratoconus. METHODS: Forty eyes of 20 patients with myopia -4.0 to -8.0 diopters (D) (mean: -6.25 +/- 1.04 D), cylinder -1.0 to -2.50 D (mean: -1.61 +/- 0.71 D), and corneal thickness 440 to 488 microm were treated with wavefront-supported PRK. Corneal topography evaluation revealed a significantly irregular cylinder (inferior-superior difference > 1.5 D) with possible mild or forme fruste keratoconus. Aberrometry was performed with the Hartmann-Shack aberrometer, and corneal data were evaluated with the Orbscan system. Eyes were treated with the Technolas 217z Bausch & Lomb excimer laser and followed for a minimum of 40 months. RESULTS: Following surgery, mean spherical equivalent refraction was +0.33 +/- 0.8 D. It was within +/- 0.5 D of the intended refraction in 95% of eyes and within +/- 1.0 D in 100% of eyes. Mean uncorrected visual acuity improved from 20/400 preoperatively to 20/25 postoperatively. Mean best spectacle-corrected visual acuity (BSCVA) remained unchanged (20/20) or improved to 20/20 in 92.5% of eyes and to 20/25 in 7.5% of eyes. Individually, BSCVA did not change in 28 (70%) eyes and increased by > or = 2 Snellen lines in 9 (22.5%) eyes; 3 (7.5%) eyes lost 1 Snellen line because of corneal haze. Laser treatment induced a significant flattening of the preoperative inferior corneal steepness in all eyes. Wavefront analysis demonstrated a significant decrease in high order aberrations (total root-mean-square and coma). CONCLUSIONS: Wavefront-supported PRK appears to be effective for the treatment of myopia and astigmatism in patients with suspected keratoconus and thin, irregular corneas. Longer follow-up is needed to prove the safety of the procedure in this patient population.

Laser in situ keratomileusis in myopic patients with congenital nystagmus.

PURPOSE: To evaluate the results of laser in situ keratomileusis (LASIK) and IntraLASIK in the treatment of myopic patients with nystagmus. METHODS: Eight patients with congenital nystagmus (16 eyes), aged 23 to 49 years, had LASIK surgery. Corneal flaps were created using the Bausch & Lomb Hansatome microkeratome or the IntraLase femtosecond laser. The ablations were performed with the Bausch & Lomb excimer laser with an active tracking system. In some patients, the eyes were fixated with forceps or a fixation ring during laser ablation. RESULTS: The refractive errors were corrected in all cases. There was no decentration or loss of best corrected visual acuity greater than 1 line. In 56% of the eyes, the postoperative uncorrected visual acuity was better than the best spectacle-corrected visual acuity (BSCVA). The BSCVA improved in 62.5% of the eyes. The overall visual performance improved in all patients. One patient who did not drive before surgery became eligible for a driver's license after surgery. CONCLUSIONS: Selected patients with myopia and congenital nystagmus may benefit from laser refractive surgery. Laser refractive surgery may be safely and accurately performed using the Hansatome microkeratome or the IntraLase femtosecond laser and an active tracking system with or without mechanical fixation. The BSCVA may improve in certain patients postoperatively.

[Lasik in myopic patients with congenital nystagmus].

PURPOSE: To present the results of IntraLASIK treatment in myopic patients with nystagmus. METHODS: Four patients, ranging in age from 25 to 49 years, with congenital nystagmus (8 eyes), underwent IntraLASIK surgery. Corneal flaps were made by Intralase femtosecond laser. In some patients, the eyes were fixated with forceps or a fixation ring during the laser ablation. In all patients, the effect of involuntary eye movements was neutralized by an active tracking system. RESULTS: The refractive errors were corrected in all cases. There was no decentration or loss of best corrected visual acuity by more than 1 line. In 3 of 8 eyes, the post-operative uncorrected visual acuity (UCVA) was equal or better than the best spectacles corrected visual acuity (BSCVA) preoperatively. Four of the 8 eyes retained or improved their BSCVA. CONCLUSIONS: Some patients with myopia and nystagmus may benefit from laser refractive surgery. By using the Intralase femtosecond laser and an active tracking system with or without mechanical fixation, laser refractive surgery may be safely and accurately performed in selected cases of nystagmus. Certain patients improve their BSCVA postoperatively.

Clinical outcome of wavefront-guided laser in situ keratomileusis in eyes with moderate to high myopia with thin corneas.

PURPOSE: To evaluate the clinical outcome of wavefront-guided laser in situ keratomileusis (LASIK) for the treatment of moderate to high myopia associated with a thin cornea. SETTING: Enaim Laser Medical Center, Tel Aviv, Israel. METHODS: This retrospective study included 98 eyes of 49 patients with moderate to high myopia (-5.20 to -10.35 diopters [D]) and thin corneas (456 to 498 mum) treated with wavefront-guided LASIK (Zyoptix, Bausch & Lomb) and followed for 36 months. Preoperative wavefront analysis was performed with a Hartmann-Shack aberrometer, and treatment was performed with the Technolas 217 z excimer laser system (Bausch & Lomb). Final refraction data, uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), optic zone size, ablation depth, optical aberrations, and night glare complaints were evaluated. RESULTS: Mean patient age was 28 years +/- 7 (SD), and mean preoperative spherical equivalent refraction was -7.06 D (range -5.20 to -10.35 D). Final UCVA ranged between 6/6 and 6/30. The safety index of the technique was 1.03, and the efficacy index was 0.67. Undercorrection of more than 0.50 D was observed in 41.3% of the high-myopic eyes (-7.00 to -10.35 D, n = 58) compared with 10% in the moderately myopic eyes (-5.00 to -6.75 D, n = 40). A significant reduction in spherical aberration (Z(4)0) was found 12 months postoperatively in all eyes. Night glare was documented in 4 eyes (4%) in the high myopia group. There were no cases of corneal ectasia. CONCLUSION: Zyoptix was safe in eyes with moderate to high myopia with relatively thin corneas (<498 microm). For myopia between -7.00 D and -10.35 D, a small optical zone (4.3 to 5.6 mm) may be applied as night glare was relatively rare, but significant undercorrection should be expected.

Evaluation of a new bioadhesive copolymer (ADAL) to seal corneal incisions.

OBJECTIVE: To evaluate the efficacy and clinical tolerance of a new acrylic copolymer tissue adhesive, ADAL, in corneal surgery. METHODS: Corneal incisions were performed on 24 New Zealand albino rabbits. The incision was either sealed with ADAL bioadhesive, hydrated with balanced salt solution, or closed with 10-0 nylon surgical sutures. The incisions underwent weekly tensile strength testing and clinical, histopathologic, and confocal microscopy evaluations. RESULTS: Clinical evaluation revealed good sealing and no incision leakage in any group. There was no anterior chamber reaction in any case. Compared with the hydrated group, there was somewhat more incisional vascularization and localized corneal opacity in the ADAL group, but there were no cases of severe corneal opacity or neovascularization. On histologic analysis, a slightly larger inflammatory reaction was noted in the ADAL group compared with the hydrated group. Tensile strength during the first week was statistically significantly greater in the ADAL group (2.93 Newtons) than in the control groups (1.40 Newtons, hydrated group; 1.43 Newtons, sutured group) (P < 0.001). Confocal microscopy study revealed a unique dendritic keratocyte shape and structure resembling shiny crystalline particles after disappearance of the adhesive from the cornea. CONCLUSIONS: Corneal surgical incisions sealed with ADAL adhesive have superior tensile strength in the first postoperative week compared with incisions closed with sutures or hydrated with salt solution. Thereafter, findings in both groups became similar. The use of ADAL adhesive was not associated with any deleterious effects during the corneal incision-healing process compared with hydration or sutures.