Outcome indicators for cross linking in pediatric keratoconus

Purpose

To evaluate the predictive factors for successful corneal collagen cross-linking (CXL) in pediatric patients with Keratoconus (KC).

Methods

This retrospective study was conducted using a prospectively built database. Patients (18 years old or younger) underwent CXL for KC between 2007 and 2017, with a 1-year follow-up period or longer. The outcomes included changes in Kmax (delta [Δ] Kmax = Kmax_last - Kmax_pre) and LogMAR visual acuity (ΔLogMAR = LogMAR_last - LogMAR_pre).The effects of CXL type (accelerated or non-accelerated), demographics (age, sex, background of ocular allergy, ethnicity), preoperative LogMAR visual acuity, maximal corneal power (Kmax), pachymetry (CCT_pre), refractive cylinder, and follow-up (FU) time on the outcomes were analyzed.

Results

One hundred thirty-one eyes of 110 children were included (mean age, 16 ± 2 years; range, 10-18 years). Kmax and LogMAR improved from baseline to last visit: from 53.81 D ± 6.39 D to 52.31 D ± 6.06 D (p < 0.001) and from 0.27 ± 0.23 LogMAR units to 0.23 ± 0.19 LogMAR units (p = 0.005), respectively. A negative ΔKmax (meaning corneal flattening) was associated with a long FU, low CCT_pre, high Kmax_pre, high LogMAR_pre, and non-accelerated CXL on univariate analysis. High Kmax_pre and non-accelerated CXL were associated with negative ΔKmax in the multivariate analysis.A negative ΔLogMAR (meaning vision improvement) was associated with a high LogMAR_pre in univariate analysis.

Conclusion

CXL is an effective treatment option in pediatric patients with KC. Our results showed that the non-accelerated treatment was more effective than the accelerated treatment. Corneas with advanced disease had a greater effect on CXL.

Predicting factors for the efficacy of cross-linking for keratoconus

Purpose

To evaluate predictors for success in corneal crosslinking (CXL) for keratoconus in a large cohort and extended follow-up.

Design

A retrospective study based on a prospectively built database.

Methods

Participants underwent CXL for keratoconus from 2007 to 2018. Statistical analysis was performed for patients with at least 1-year follow-up. We analyzed effects of CXL type (Epithelium-on or Epithelium-off and Accelerated (9mW/cm2@10min) or Standard (3mW/cm2@30min)) and pre-operative factors including age, gender, baseline LogMAR visual acuity (LogMARpre), maximal corneal power (Kmaxpre), pachymetry, refractive and topographic cylinders, spherical equivalent (SEpre), mean corneal power (MeanK) and follow-up time on outcome measures. The outcome measures were the final change of Kmax (Delta Kmax) and the final change in LogMAR visual acuity (Delta LogMAR). A more negative Delta Kmax or Delta LogMAR represents a favorable effect of crosslinking.

Results

517 eyes had Kmax results, and 385 eyes had LogMAR results with more than one year follow-up. These eyes were included in the study. The mean follow-up time was 2.29 years. Mean Kmax decreased from 54.07±5.99 diopters to 52.84±5.66 diopters (p<0.001), and Mean LogMAR decreased from 0.28±0.20 to 0.25±0.21 (p<0.001). Non-accelerated epithelium-off CXL resulted in greater flattening of Kmax when compared with other protocols. Visual acuity improvement was similar when comparing different CXL protocols. Multivariate analysis showed four factors associated with negative Delta Kmax: high Kmaxpre, high SEpre, high MeanKpre, and non-accelerated procedure. Multivariate analysis showed three factors associated with negative Delta LogMAR: high LogMARpre, high SEpre, and Low MeanKpre. After excluding corneas with Kmaxpre >65 D or Pachymetry<400 microns, multivariate analysis showed that high Kmaxpre, high SEpre, and non-accelerated CXL were associated with negative Delta Kmax while high LogMARpre and high SEpre were associated with negative Delta LogMAR.

Conclusion

CXL for keratoconus is a highly effective treatment, as evident by its effects on the outcome measures: Delta Kmax and Delta LogMAR. CXL was more successful in eyes with high Kmaxpre, high SEpre, and high LogMARpre, which express disease severity. The non-accelerated epithelium-off protocol was associated with greater flattening of corneal curvature but did not show a better effect on visual acuity as compared to the other CXL protocols.

Hydrogel probe for iontophoresis drug delivery to the eye

The aim of this study was to evaluate the use of a solid hydrogel loaded with a drug solution as a probe for ejecting drugs to the eye upon application of low current iontophoresis. Hydroxyethyl methacrylate (HEMA), cross-linked with ethylene glycol dimethacrylate (EGDMA), and cross-linked arabinogalactan or dextran were prepared to form solid hydrogels. The hydrogels were examined for their mechanical suitability, absorption of drug solution and in vitro release properties when applying an iontophoretic current through the drug-loaded hydrogel into a solid-agar surface. Transconjunctival and transscleral iontophoresis of gentamicin sulfate was studied in healthy rabbits using drug-loaded disposable HEMA hydrogel disc probes. Gentamicin concentrations in different eye segments were assayed using a fluorescence polarization immunoassay. Preliminary corneal toxicity was examined in rabbits using a current intensity of 2.5 and 5.1 mA/cm2 for 60 and 120 s. The most appropriate hydrogel is composed of HEMA, 2% EGDMA and 75% water. lontophoresis onto agar gel was found indicative for the evaluation of iontophoretic activity of a hydrogel. Transscleral iontophoretic treatment resulted in high concentrations of drugs in the posterior segments of the eye. Application of iontophoresis onto the rabbit eye caused a reversible swelling of the cornea which lasted a few hours after application. Low current iontophoresis using drug-loaded hydrogel has a potential clinical value in obtaining high drug concentration at posterior segments of the eye.

LASIK correction of vision in adults with unilateral amblyopia

PURPOSE

to evaluate the effects of laser refractive surgery in adult patients with mild to moderate amblyopia due to anisometropic myopia.

METHODS

a retrospective review of 30 patients (60 eyes) with unilateral amblyopia (corrected distance visual acuity [CDVA] 0.6 or worse) who underwent simultaneous bilateral laser vision correction using the Technolas 217z excimer laser (Bausch & Lomb) was performed. Mean patient age was 31.03 ± 10.05 years (range: 18 to 53 years). Visual outcomes in the amblyopic eye were compared with those in the fellow nonamblyopic control eye of the same patient.

RESULTS

mean preoperative CDVA improved in amblyopic eyes from 0.50 ± 0.13 to 0.57 ± 0.20 postoperatively (average gain of 0.075 ± 0.14; P=.007) and improved from 0.92 ± 0.12 preoperatively to 0.93±0.15 after surgery (mean gain of 0.013 ± 0.14; P=.603) in the fellow nonamblyopic eyes. The safety index was significantly greater in the amblyopic eyes compared with the nonamblyopic fellow eyes (1.15 ± 0.30 vs 1.02 ± 0.15, P=.035), therefore, no difference was noted in efficacy (P=.913). Five of 30 eyes with mild to moderate amblyopia gained 2 to 4 lines of CDVA.

CONCLUSIONS

laser refractive surgery for myopic correction was found to be safe and effective in eyes with mild to moderate amblyopia.

The effect of corneal grafting on vision in bilateral amblyopia

Two children with bilateral congenital corneal opacities (sclerocornea) received unilateral corneal transplants at the ages of 4 1/2 and 16 years, respectively. Both developed reading vision and reduced nystagmus excursions.

In vitro and in vivo evaluation of carboplatin delivery to the eye using hydrogel-iontophoresis

PURPOSE

To investigate in vitro and in vivo hydrogel-iontophoresis delivery of carboplatin to the eye.

METHODS

Iontophoresis was applied on agar gels resembling the eye using different current intensities and durations. Transscleral iontophoresis was performed on healthy rabbits, applying 0, 1, and 3 mA current for 10 min.

RESULTS

Similar drug concentrations were obtained in all experimental groups, in in vitro and in vivo studies, regardless of the iontophoretic current applied. A 20-mm penetration depth was found for carboplatin at the agar model. High drug levels were found at the sclera and retina, while lower levels were found at ocular fluids.

CONCLUSION

Carboplatin-iontophoretic application at the above conditions does not have an obvious advantage over passive penetration due to high diffusion properties and insufficient molecular charge. Passive carboplatin diffusion from loaded hydrogels inserted in the lower cul-de-sac should be further investigated as a potential clinical treatment for intraocular retinoblastoma.

Methotrexate delivery to the eye using transscleral hydrogel iontophoresis

PURPOSE

To evaluate methotrexate penetration and distribution profile in ocular structures after short low current transscleral hydrogel iontophoresis.

METHODS

Methotrexate iontophoresis was studied in rabbits using drug-loaded hydrogels mounted on a portable iontophoretic device. Drug distribution profile was evaluated 2, 4, and 8 hours after iontophoretic treatment of 1.6 mA/cm2 for 4 min. Ocular drug levels were also determined two hours after iontophoretic treatment of 5 mA/cm2, compared to mock iontophoresis and intravitreal injection of methotrexate.

RESULTS

Therapeutic drug levels were maintained for at least 8 h at the sclera and retina and for 2 h at the aqueous humor following the iontophoretic treatment. After increasing the current density, a twice-higher concentration was achieved at the vitreous and 8 to 20 time higher concentrations at the retina and sclera.

CONCLUSIONS

A short low current non-invasive iontophoretic treatment using methotrexate-loaded hydrogels has a potential clinical value in treating ocular inflammatory diseases and intraocular lymphoma.

[Transcorneal and transscleral iontophoresis of the dexamethasone phosphate into the rabbit eye]

PURPOSE

To evaluate the efficiency of the dexamethasone phosphate penetration into the rabbit eye after transcorneal and transscleral iontophoresis using a drug loaded hydrogel assembled on a portable iontophoretic Mini Ion device.

METHODS

lontophoresis of dexamethasone phosphate was studied in healthy rabbits using drug-loaded disposable HEMA hydrogel sponges and portable iontophoretic device. Corneal iontophoretic administration was performed with electric current of 1 mAmp for 1, 2, and 4 min. In the control group, the dexamethasone was applied in drops into the conjunctival sac. Transconjunctival and transscleral iontophoresis were performed in the pars plana area, through the conjunctiva or directly on the sclera. Dexamethasone concentrations were assayed using HPLC method. To study the anatomical changes after iontophoresis application, histological examinations of corneas excised 5 minutes and 8 hours after the procedure were performed.

RESULTS

Dexamethasone levels in the rabbits' corneas after a single transcorneal iontophoresis were up to 38 times higher compared to those obtained after topical eye drops instillation. High drug concentrations were obtained in the retina and sclera 4 hours after transscleral iontophoresis as well. There were no statistically significant differences in the drug concentration after transscleral and tranconjunctival iontophoresis. Histological examination of the corneas after the iontophoresis showed only discrete reversible changes of the epithelium and the stroma.

CONCLUSION

A short, low-current, non-invasive iontophoretic treatment using the dexamethasone-loaded hydrogels has a potential clinical value in increasing the drug's penetration into the anterior and posterior segment of the eye.

Early Transient Visual Acuity Loss After LASIK Due to Steroid-induced Elevation of Intraocular Pressure

PURPOSE

To report the clinical course of early transient reduction of uncorrected visual acuity (UCVA) after LASIK surgery resulting from steroid-induced elevation of intraocular pressure (IOP).

METHODS

Twenty-nine eyes of 15 patients who received topical corticosteroids after uneventful myopic LASIK surgery and had a decrease in UCVA within the first 3 weeks were evaluated retrospectively.

RESULTS

Intraocular pressure increased by 4 to 30 mmHg from preoperative to postoperative days 4 to 20. Twenty-seven of 29 eyes had a decrease in UCVA and/or best spectacle-corrected visual acuity (BSCVA). All eyes, except one, had edema without evidence of inflammation in the interface or the remainder of the cornea. Discontinuation of topical corticosteroids and application of anti-glaucoma medications resulted in a decrease of IOP to normal levels, reduction or disappearance of the edema, and recovery of BSCVA.

CONCLUSIONS

Early onset steroid-induced elevation of IOP after LASIK may cause corneal edema and a sudden decrease in UCVA. Rapid diagnosis and treatment can control IOP and recover the visual loss.

Iontophoretic treatment of experimental pseudomonas keratitis in rabbit eyes using gentamicin-loaded hydrogels

PURPOSE

To evaluate the efficacy of iontophoresis using a hydrogel probe containing gentamicin for the treatment of Pseudomonas keratitis in the rabbit cornea.

METHODS

Five groups (Groups 1-5) of 8 rabbits each were infected by injecting Pseudomonas aeruginosa into their corneas. Three dosings of corneal iontophoresis were performed, at intervals of 3.5 hours, using soft disposable gentamicin-loaded hydroxyethyl methacrylate hydrogel discs mounted on a portable iontophoretic device. Groups 1 and 2 were treated with corneal iontophoresis for 60 seconds and a current of 0.5 and 0.2 mA. Groups 3 and 4 were treated with hydrogel loaded with 0.9% NaCl solution, using a current of 0.2 mA and mock iontophoresis. Group 5 was treated with eye drops of 1.4% gentamicin every hour for 8 hours. One and a half hours after the last treatment, the animals were killed, and the corneas were excised and cultured for P. aeruginosa count after 24-hour incubation.

RESULTS

After iontophoretic treatment of gentamicin with a current of 0.5 mA (Group 1), the logarithmic value of Pseudomonas colony-forming units (CFUs) was 2.96 +/- 0.45. After lower current iontophoretic treatment (Group 2), the logarithmic Pseudomonas count was 5.25 +/- 0.54 CFUs. At the control groups (Groups 3-5), the Pseudomonas counts were found to be much higher, 7.62 +/- 0.28, 7.22 +/- 0.29, and 6.29 +/- 0.45 CFUs, respectively.

CONCLUSION

A short iontophoretic treatment using gentamicin-loaded hydrogels has potential clinical value in treating corneal infections.

Astigmatism After Mersilene and Nylon Suture Use for Penetrating Keratoplasty

PURPOSE

To evaluate postoperative astigmatism after the use of Mersilene and nylon sutures for penetrating keratoplasty.

METHODS

Two groups of 12 patients each (age, 20-50 years) suffering from keratoconus underwent penetrating keratoplasty. Continuous suturing combined with 12 interrupted sutures was used in each case: Mersilene 11-0 sutures were used in group 1, whereas nylon 10-0 sutures were used in group 2. Sutures were removed to control astigmatism when required. All patients were monitored for 36 months.

RESULTS

During the follow-up period, sutures were removed in each eye as indicated by astigmatism or breakage. In group 1 (Mersilene 11-0 sutures), no breakage of sutures was recorded. In group 2 (nylon 10-0 sutures), breakage of sutures was recorded in 11 of 12 cases. However, continuous sutures were removed in 2 patients in group 2. After the first year, the astigmatism remained within +/-1.00 diopter in all except 1 patient in group 1 and in 5 patients in group 2. No suture-related complications were recorded except for scarring with photophobia in 1 patient in group 1 and suture breakage in 11 eyes in group 2.

CONCLUSION

Mersilene sutures can provide a stable postoperative astigmatism, whereas nylon sutures have a tendency to break and cause changes in corneal astigmatism.

Conjunctival autografting combined with low-dose mitomycin C for prevention of primary pterygium recurrence

PURPOSE

To compare the clinical outcome of pterygium surgery combining intraoperative mitomycin C (MMC) with a free conjunctival autograft, with three other methods of pterygium surgery, including intraoperative MMC alone, conjunctival autograft alone, and bare sclera without adjunctive treatment.

DESIGN

Interventional, randomized and in part nonrandomized, prospective, comparative study.

METHODS

setting: A university medical center department of ophthalmology.

STUDY POPULATION

One hundred and twenty patients underwent pterygium excision surgery. These patients were divided into four treatment groups.

INTERVENTION

In group 1 (30 patients), MMC, 0.2 mg/ml, was applied for three minutes. In group 2 (30 patients), conjunctival autografting was performed. Group 3 (30 patients) received sodium chloride 0.9% only, and group 4 (30 patients) underwent conjunctival autografting combined with one minute application of MMC, 0.2 mg/ml.

MAIN OUTCOME MEASURE

Recurrence rates and complications.

RESULTS

Pterygium recurred in two patients (6.6%) in group 1, in four patients (13.3%) in group 2, in 14 patients (46.6%) in group 3, and in none of the patients in group 4. chi(2) analysis revealed a significantly lower recurrence rate in group 4 compared with group 2 (P = .038) and with group 3 (P < .0001). Epithelialization of the wounds was complete within 14 days of surgery. No complications were demonstrated in any of the study groups except for one case of minor melting of the flap in group 4.

CONCLUSIONS

This study indicates that pterygium excision with a free conjunctival autograft combined with intraoperative low-dose MMC is a safe and effective technique in pterygium surgery.

[Delivery of gentamicin to the rabbit eye using hydrogel and iontophoresis]

The aim of this study was to evaluate the use of solid hydrogel as a probe for the drug delivery to the rabbit eye upon application of low current iontophoresis. Hydroxyethyl methacrylate (HEMA), cross-linked with ethylenglycol dimethacrylate (EGDMA) were prepared to form solid hydrogels. The concentrations of gentamicin sulfate in different segments of rabbit eye after transconjunctival and transscleral iontophoresis were also studied. For iontophoresis we used a portable Mini Ion device (designed at Hebrew University of Jerusalem) and applied a current from 0 mA to 1.5 mA for pre-set period from 30 to 120 seconds and after application the concentrations of gentamicin in cornea were assayed. The rabbits in control group were treated with fortified gentamicin eye-drops (concentration 1.4 %). The highest concentration of gentamicin sulfate was reached after iontophoresis with current intensity of 1.5 mA applied for 60 s. High gentamicin concentration were found in the retina and in the sclera four hours after transscleral iontophoresis, the lowest concentration was obtained in vitreous. The delivery of gentamicin to the eye via iontophoresis with solid HEMA/EGDMA hydrogels seems to be promising method achieving high concentrations of the drug in the eye tissue.

Transcorneal and transscleral iontophoresis of dexamethasone phosphate using drug loaded hydrogel

PURPOSE

To evaluate dexamethasone penetration to the eye after a short transcorneal and transscleral iontophoresis using a drug loaded hydrogel assembled on a portable iontophoretic device.

METHODS

Iontophoresis of dexamethasone phosphate was studied in healthy rabbits using drug loaded disposable HEMA hydrogel sponges and portable iontophoretic device. Corneal iontophoretic administration was performed with a current intensity of 1 mA for 1 and 4 min. Transconjunctival and transscleral iontophoresis were performed twice for 2 min at two near places in the pars-plana area, on the conjunctival membrane or directly on the sclera. Dexamethasone concentrations were assayed using HPLC.

RESULTS

Dexamethasone levels in the rabbit cornea after a single transcorneal iontophoresis for 1 min were up to 30 fold higher compared to those obtained after frequent eye drop instillation. Also, high drug concentrations were obtained in the retina and sclera 4 h after transscleral iontophoresis.

CONCLUSIONS

A short low current non-invasive iontophoretic treatment using dexamethasone-loaded hydrogels has potential clinical value in increasing drug penetration to the anterior and posterior segments of the eye.

Two Cases of Pneumococcal Keratitis Following Myopic LASIK

PURPOSE

To report two cases of pneumococcal keratitis after LASIK.

METHODS

Retrospective interventional small case series of two patients who underwent bilateral LASIK for myopia and developed pneumococcal keratitis after surgery. This complication was encountered 2 days after surgery in one eye in both cases. The corneal flap was lifted, and irrigation and cultures from the stromal bed performed. Topical and subconjunctival antibiotics were started.

RESULTS

Culture revealed Streptococcus pneumoniae in both cases. The infiltrates responded well to treatment. One year after the procedure, uncorrected visual acuity is > 20/40 in both cases.

CONCLUSIONS

Pneumococcal keratitis can complicate LASIK. Patients should be informed of this potential complication, as prompt treatment is crucial.

Increased Expression of Inflammatory Cytokines and Matrix Metalloproteinases in Pseudophakic Corneal Edema

PURPOSE

To evaluate the expression of inflammatory cytokines and matrix metalloproteinases in the corneal epithelium in pseudophakic corneal edema (PCE).

METHODS

Tissue sections were prepared from formalin-fixed, paraffin-embedded blocks of corneal buttons removed from 20 patients with PCE during penetrating keratoplasty (PKP) and from 11 age-matched control eyes enucleated because of uveal melanoma. Expression of interleukin (IL)-1beta, -6, and -8; vascular endothelial growth factor (VEGF); and matrix metalloproteinase (MMP)-1, -3, and -9 proteins in the corneal epithelium was evaluated by immunohistochemistry. Digital image analysis was performed to quantify the expression of the various cytokines and MMPs. A mean intensity stain index (ISI), based on the staining density and the area stained, was calculated from digital images captured from sequential areas of the corneal epithelium.

RESULTS

The expression of most of the inflammatory cytokines and MMPs was significantly higher in the corneal epithelium of PCE corneal buttons than in the control specimens. MMP-9 had the highest expression when compared with the control (ISI = 55.08 +/- 23.71 in PCE compared with 0.169 +/- 0.156 in the control; P < 0.0001). Significantly higher ISIs were also recorded for MMP-1 (16.14 +/- 8.49 vs. 1.13 +/- 1.79; P < 0.0001), IL-1beta (62.62 +/- 27.23.97 vs. 1.61 +/- 1.27; P < 0.0001), IL-8 (37.91 +/- 21.18 vs. 4.24 +/- 3.60; P < 0.0001), and VEGF (81.67 +/- 26.22 vs. 19.40 +/- 16.85; P = 0.0001). The expression of MMP-3, IL-6, and TNF-alpha in PCE was not different from control expression. Significant positive correlations were found between the expression of IL-1beta and MMP-9 (r(2) = 0.37; P = 0.015), between VEGF and IL-8 (r(2) = 0.22; P = 0.042), and a significant correlation was found between the expression of MMP-3 and TNF-alpha (r(2) = 0.5197; P = 0.0007). The expression of TNF-alpha correlated significantly with the patient's age (r(2) = 0.28; P = 0.0195).

CONCLUSIONS

The corneal epithelium in PCE expresses high levels of cytokines and matrix-degrading enzymes, which are associated with inflammation, wound healing, angiogenesis, and tissue degradation. The expression of these mediators may partially explain the pathologic features associated with this disease, such as bulla formation, recurrent epithelial desquamation, and corneal neovascularization.

Forty Years of Changing Indications in Penetrating Keratoplasty in Israel

PURPOSE

To examine the leading indications for keratoplasty and identify the changing trends in the past 40 years in Israel.

METHODS

Pathology reports of all penetrating keratoplasties (PKPs) performed at Hadassah-Hebrew University Hospital from 1961 to 2000 were reviewed. We evaluated the indications for keratoplasty in each decade between the years 1961 and 2000.

RESULTS

During the 40-year period, a total of 1681 PKPs were performed. Keratoconus (n = 478, 28.4%) was the most common indication, followed by graft failure (n = 226, 13.4%), pseudophakic corneal edema (PCE) (n = 142, 8.4%), herpetic infections (n = 125, 7.4%), nonherpetic infections (n = 114, 6.8%), scarring (n = 113, 6.7%), and trauma (n = 110, 6.5%). The 7 groups account for approximately 77.5% of all keratoplasties performed. Ocular infections were the most common indications before 1970 and have been declining ever since. Keratoconus became the leading indication in the past 30 years. In the past decade, of 663 keratoplasties, keratoconus was the most common indication (56, 38.6%) followed by graft failures/rejections and PCE (the second most common indication between the years 1981 and 1990).

CONCLUSIONS

Keratoconus was the leading indication for keratoplasty in our series. There was a decreasing trend in PK for ocular herpetic infections during the decades. The rate of PCE decreased while failed graft became the second most common indication for PKP during the past decade.

The treatment of primary acquired melanosis (PAM) with atypia by topical Mitomycin C

PURPOSE

To report our results of 12 consecutive patients with conjunctival primary acquired melanosis (PAM) with atypia who were treated by topical Mitomycin C (MMC).

DESIGN

Retrospective interventional consecutive case series.

METHODS

Twelve patients with PAM with atypia in one of their eyes who were treated by topical chemotherapy with MMC were included in this case study. Eyes with histologically proven PAM with atypia were treated by two to five courses of 0.04% (0.4 mg/ml) MMC four times a day. Each course lasted 2 continuous weeks. Follow-up was conducted on patients for control of local disease, side effects, and visual acuity in the treated eye.

RESULTS

In all patients, there was complete or partial response to treatment. In four patients, the pigmentation disappeared, whereas in eight patients, some remnants of the pigmentation remained. In seven of these eight patients, the remnants of the pigmentation were stable during the follow-up period of 4 months to 9 years, whereas one in whom re-growth of the PAM was noticed was successfully treated again by topical MMC. No patients lost visual acuity at the end of the follow-up. All side effects of the local chemotherapy were resolved after cessation of the treatment.

CONCLUSIONS

Topical MMC chemotherapy is a good alternative to surgical excision and cryotherapy in treating conjunctival PAM with atypia.

Mitomycin C for pterygium: long term evaluation

AIM

To evaluate long term complications after pterygium excision with mitomycin C (MMC) application.

DESIGN

Prospective non-comparative interventional case series.

PARTICIPANTS

Ninety nine patients who underwent pterygium surgery and participated in a controlled study for efficacy of MMC for pterygium surgery between 1989 and 1994.

METHODS

Patients who were located and agreed to come for examination underwent a complete eye examination. The bare sclera area, in particular, was examined for possible complications. The main outcome measures were anatomical findings in area of MMC application.

RESULTS

Forty three eyes of 43 patients were examined. Sixty three per cent of patients had pterygium surgery with intraoperative application of 0.02% MMC for 5 minutes and 37% of patients received MMC 1% or 2% drops four times daily for 2 weeks postoperatively. In three patients, pterygium recurred within 18 months. The only complication was mild conjunctival avascularity in areas of pterygium excision in 30% of patients.

CONCLUSION

Long term evaluation revealed that the use of MMC in pterygium surgery is safe, but for a strict selection of patients, controlled use of MMC and long term follow up are required.

Long-term effects of mitomycin C in pterygium surgery on scleral thickness and the conjunctival epithelium

PURPOSE

To evaluate the long-term effects of intraoperative application of mitomycin C on the scleral thickness and the conjunctival epithelium at the surgical site of pterygium excision.

DESIGN

Prospective observational case series.

PARTICIPANTS

Twenty-four patients who underwent excision of primary pterygium with intraoperative mitomycin C in our department during the year 1996.

METHODS

Patients were evaluated by slit-lamp biomicroscopy, impression cytology, and high-frequency ultrasonography. Impression cytology was performed by applying a small nitrocellulose filter paper for a few seconds at the excision area and for a few seconds at the opposite perilimbal area, and subjecting the specimens to the periodic acid-Schiff-Gill modified Papanicolaou staining protocol. The morphology of the conjunctival epithelium and goblet cell density (GCD) were recorded. High-frequency ultrasound was performed at the same sites, and the scleral thickness was measured at a distance of 1 mm from the limbus.

MAIN OUTCOME MEASURES

Goblet cell density, conjunctival epithelial morphology, and the scleral thickness at the operated and nonoperated sites.

RESULTS

All patients had successful pterygium removal with no corneal recurrence after a mean follow-up of 77.2+/-3.9 months (range, 72-84). Impression cytology revealed normal nongoblet conjunctival epithelial cells at the excision area, with a 4-fold decrease in the GCD at the excision area when compared with the contralateral nonoperated site (296+/-120 cells/mm(2) and 1183+/-310 cells/mm(2), respectively; P = 0.0036). No differences were noted between the scleral thicknesses at the operated site (750+/-70 microm) and the opposite site (740+/-80 microm) (P = 0.84).

CONCLUSIONS

A single application of mitomycin C after pterygium excision is not associated with reduction in scleral thickness more than 6 years postoperatively. The conjunctival epithelium retains its normal phenotype, with a marked reduction of the GCD.

Delivery of Gentamicin to the Rabbit Eye by Drug-Loaded Hydrogel Iontophoresis

PURPOSE

To assess the corneal iontophoretic delivery of gentamicin by drug-loaded hydrogel probe, and to determine the resultant ocular disposition and elimination of the drug from the cornea and anterior chamber.

METHODS

Corneal iontophoresis of gentamicin sulfate was studied in healthy white rabbits by using drug-loaded disposable hydroxyethyl methacrylate (HEMA) hydrogel disk probes and a portable mini-ion device designed in the authors' laboratory. The iontophoretic treatment was performed with a current intensity of 1 mA for 60 seconds only. Three control groups were used: mock iontophoresis (no current) for 60 seconds, topical eye drops of fortified gentamicin (1.4%) every 5 minutes for 1 hour, and subconjunctival injection of 0.25 mL of 40 mg/mL gentamicin solution. The animals in the iontophoretic experimental groups were killed at predetermined time points. The gentamicin concentrations in the cornea and aqueous humor were assayed with a fluorescence polarization immunoassay. Analysis of the gentamicin eye pharmacokinetics was performed with a modeling approach.

RESULTS

Peak gentamicin concentrations in the cornea (363.1 +/- 127.3 microg/g) and in the aqueous humor (29.4 +/- 17.4 microg/mL) were reached at 0 and 2 hours after the iontophoretic treatment, respectively. The peak gentamicin concentrations after a single iontophoresis treatment were 12 to 15 times higher than those obtained after gentamicin injection or after topical eye drop instillation, and much higher than in mock iontophoresis. The concentration versus time profile of gentamicin in the cornea and the anterior chamber after iontophoresis was appropriately described by applying a two-compartment pharmacokinetic model.

CONCLUSIONS

A short iontophoretic treatment using gentamicin-loaded hydrogels has potential clinical value in increasing drug penetration to the anterior segments of the eye and maintaining therapeutic drug levels in the cornea for more than 8 hours.

Surgical Management of Corneal Plaques in Vernal Keratoconjunctivitis

PURPOSE

To describe the surgical management and histopathologic and immunohistochemical findings in corneal plaques of shield ulcers in vernal keratoconjunctivitis.

PATIENTS AND METHODS

Three children (ages 4, 7.5, and 9) presented with corneal plaques unresponsive to conservative systemic and topical medical treatment. Plaques were scraped under general anesthesia, and soft bandage contact lenses were placed. The excised tissue was evaluated by histopathology and immunohistochemistry.

RESULTS

During surgery, plaques were found to extend beyond the ulcer margins. Histopathology revealed granular, deeply-eosinophilic, laminar material, firmly attached to the Bowman layer in all cases. Immunohistochemistry confirmed this to be eosinophil-derived major basic protein (MBP). After surgical removal, complete epithelization was evident within 1-4 weeks in all cases.

CONCLUSIONS

Corneal plaque is a rare complication of vernal keratoconjunctivitis. These plaques usually do not resolve with standard conservative measures. Failure to epithelialize may be a result of the plaque material extending below the edges of adjacent epithelium. We suggest that MBP plaques precipitate on the denuded stromal bed, thereby playing a pathogenic role in nonhealing shield ulcers.

Iontophoresis–gentamicin delivery into the rabbit cornea, using a hydrogel delivery probe

PURPOSE

To evaluate the efficacy of penetration of gentamicin into the cornea of rabbits using iontophoresis with a hydrogel-gentamicin containing probe.

METHODS

Eight of 10 groups (groups 3-10) of 6 rabbits (one eye per rabbit), underwent corneal iontophoresis using soft stable hydroxyethyl methacrylate hydrogel discs (80% water content) loaded with gentamicin sulphate which were mounted on an iontophoresis probe. The studied current intensities were 0, 0.1, 0.3 and 0.6 mAmp, and the durations of iontophoresis were 10 and 60 sec. Two control groups received 1.4% topical drops of gentamicin every 5 min for 1 hr (group 1) or sub-conjunctival injection of 10 mg gentamicin (group 2). Following sacrifice, aqueous humour was taken, corneas were excised, and gentamicin concentration was determined in aqueous humour and cornea samples.

RESULTS

Post-iontophoresis, the concentration of gentamicin in the corneas ranged from high (88.60 +/- 38.64 microg ml(-1)) to very low (0.10 +/- 0.89 microg ml(-1)). Both the control groups and those rabbits treated with current intensity of 0.1 mAmp or greater obtained therapeutic gentamicin levels in the corneas. Use of iontophoresis for 60 sec or current intensity greater than 0.1 mAmp obtained corneal gentamicin levels not different from sub-conjunctival injection. Application of current intensity of 0.1 mAmp or greater gave corneal gentamicin concentrations comparable to topical application of the drug, except when 0.6 mAmp were used for 60 sec (p = 0.05). Increasing current intensity or duration of iontophoresis significantly increased (p = 0.001 for both) gentamicin penetration into the cornea. Current intensity had more influence (Beta2 = 0.40) than duration (Beta2 = 0.13) on drug penetration. A significant interaction was found between the duration of iontophoresis and the current intensity. Very small or no concentrations of the drug were discovered in the anterior chambers of rabbits.

CONCLUSIONS

Iontophoresis using hydrogel-gentamicin probe may deliver therapeutic concentrations of gentamicin into the cornea.

To lift or recut: Changing trends in LASIK enhancement

PURPOSE

To report serious complications caused by recutting laser in situ keratomileusis (LASIK) flaps for enhancement and reconsider the current preferred method of LASIK enhancement.

SETTING

Multiple surgeon practices.

METHODS

This retrospective noncomparative nonconsecutive case series comprised LASIK patients in the private practices of 9 experienced refractive surgeons and those reported in a survey of refractive surgeons. Case histories, refractions, corneal topographies, slitlamp photographs, and measurements of uncorrected and best corrected (BCVA) visual acuity after recutting LASIK flaps were collected. Surveys of refractive surgeons and an analysis of changing practice trends among the authors and these surgeons were assessed.

RESULTS

In 12 cases, significant loss of BCVA and subjective visual difficulties resulted from recutting LASIK flaps. Most surveyed surgeons had changed their practice from recutting to lifting flaps even 9 to 10 years postoperatively with good results.

CONCLUSION

Recutting flaps for enhancement should be avoided unless other alternatives are unavailable.

Long-term evaluation of hyperopic laser in situ keratomileusis

PURPOSE

To evaluate the efficacy, safety, and predictability of hyperopic laser in situ keratomileusis (H-LASIK).

SETTING

Departments of Ophthalmology, Hadassah University Hospital, Jerusalem, and Assaf Harofeh Medical Center, Zerifin, Israel.

METHODS

This prospective noncomparative case series studied the results of H-LASIK in the first 92 consecutive eyes of 50 patients with up to +10.25 diopters (D) of hyperopia. For analysis, the patients were divided into 3 groups based on preoperative hyperopia: low hyperopia (< +3.00 D), moderate hyperopia (> or = +3.00 to 6.00 D), and high hyperopia (> or = +6.00 D).

RESULTS

Forty-two patients, 77 eyes (83.7%), were followed for at least 12 months. At 12 months, the mean manifest spherical equivalent was +0.33 +/- 0.65 D (93.1% of eyes within +/-1.0 D of the intended correction) in the low myopia group, +0.21 +/- 0.60 D (92.3% within +/-1.0 D of the intended correction) in the moderate hyperopia group, and +1.62 +/- 1.50 D (36.4% within +/-1.0 D of the intended correction) in the high hyperopia group. The uncorrected visual acuity (UCVA) was 20/40 or better in all eyes (100%), 24 eyes (92.3%), and 13 eyes (59.1%) in the low, moderate, and high hyperopia groups, respectively. Comparing the UCVA at the last examination with the best corrected visual acuity (BCVA) before surgery in all patients showed that 59 eyes (76.6%) were within +/-1 line and 18 eyes (23.4%) were within +/-2 or more lines of the preoperative BCVA. Three eyes (3.9%) in the high hyperopia group lost 2 or more lines of BCVA. Three eyes (3.9%) had flap- related complications. Eight patients (15 eyes) with a follow-up less than 12 months did not have intraoperative or postoperative complications.

CONCLUSION

Laser in situ keratomileusis was a safe, effective, and predictable procedure for hyperopia up to +6.0 D and less predictable for higher hyperopia.

Inadvertent conjunctival trauma related to contact with drug container tips: a masquerade syndrome

PURPOSE

To report the diagnosis, clinical course, and management of acute painful red eye syndrome associated with unintentional tube- or bottle-tip-induced conjunctival trauma.

DESIGN

A small, noncomparative, interventional case series.

PARTICIPANTS

Twelve eyes of 12 patients (8 female and 4 male, aged 21-84 years) who were urgently reported or referred with a variety of diagnoses resulting from acute onset of red, painful eye. Four eyes had corneal transplants, two were recovering from herpetic keratitis, two had undergone cataract surgery or a laser in situ keratomileusis procedure, one had a corneal neurotrophic ulcer, and one used a contact lens. All the patients had received new medications (ophthalmic ointments in nine patients, topical drops in three patients) within 1 week before onset of symptoms.

INTERVENTION

Assessment of method of self-administration of topical medication, evaluation of the ocular surface lesion, and patient education.

MAIN OUTCOME MEASURES

Association of patient behavior with ocular surface lesions.

RESULTS

All 12 patients presented red, painful eyes, congested lower palpebral conjunctiva, epithelial conjunctival erosions, and episcleritis. In all patients, direct contact of the tube or bottle-tip with the affected area of the conjunctiva was ascertained by inspection. Instructions on proper method of drug administration and eye patching with lubrication were followed, within 2 weeks, by healing of conjunctival lesions.

CONCLUSIONS

Drug containers may cause nonintentional conjunctival trauma and simulate severe ocular disorders. Physicians should be aware of this diagnosis in any case of prolonged and unexplained ocular irritation and should instruct patients as to the proper instillation of topical ophthalmic medications.

Intraocular pressure after LASIK for hyperopia

PURPOSE

To determine whether hyperopic laser in situ keratomileusis (H-LASIK) affects Goldmann applanation tonometry measurements.

DESIGN

Retrospective, comparative, self-controlled case series.

PARTICIPANTS

One hundred eight eyes of 58 patients were enrolled in the study.

METHODS

Baseline intraocular pressure (IOP) was measured by Goldmann applanation tonometry. These readings were compared with readings obtained at least 6 months after surgery.

RESULTS

After H-LASIK, a decrease was observed in the measured IOP of treated eyes that could not be related to the degree of hyperopia treated or to the treatment zone diameter. A significant difference was observed between the IOP before and after surgery (P < 0.00001).

CONCLUSIONS

The applanation tonometer underestimates the true IOP after LASIK for hyperopia.

Anterior ischemic optic neuropathy after a trans-Atlantic airplane journey

PURPOSE

To report a case of anterior ischemic optic neuropathy after a trans-Atlantic airplane journey.

DESIGN

An observational case report.

METHODS

A 48-year-old healthy man presented with severe visual loss in his left eye within 12 hours after a 15-hour-long trans-Atlantic airplane flight. The patient underwent slit-lamp examination, funduscopy, fluorescein angiography, automated perimetry, and various blood examinations.

RESULTS

Visual acuity was LE: 20/30, and a mild left eye relative afferent pupillary defect was noted. Funduscopic evaluation revealed an edematous optic disk in the left eye with a para-diskal retinal hemorrhage. Fluorescein angiography revealed a leaking optic disk, and perimetry showed an inferior hemi-field scotoma. Anterior ischemic optic neuropathy was diagnosed.

CONCLUSION

Prolonged airplane travel may compromise vision either by a thromboembolic mechanism caused by prolonged immobilization or by a vasospasm mechanism induced by the low oxygen pressure during the flight.

Topical mitomycin-C for partially excised conjunctival squamous cell carcinoma

PURPOSE

To evaluate the efficacy of topical mitomycin-C (MMC) for treatment of postoperative residual conjunctival squamous cell carcinoma (SCC).

DESIGN

Retrospective noncomparative case series.

PARTICIPANTS

Five patients, two males and three females, with conjunctival and histologically proven incompletely excised conjunctival SCC.

METHODS

Patients were treated with topical MMC. Two to three courses of topical MMC, 0.02% or 0.04%, were applied four times daily for 14 days per course. One month after the final treatment, the scar area with surrounding normal conjunctiva was excised, and histologic evaluation was done.

MAIN OUTCOME MEASURES

No evidence of malignant cells in excised tissues.

RESULTS

Histologic evaluation of the five specimens showed no malignant cells. Conjunctival scarring with inflammatory response was observed. No regrowth was reported during the follow-up period of 18 to 37 months. The complications of MMC use included mild to moderate conjunctival hyperemia in three patients. All signs and symptoms were resolved after discontinuation of the treatment.

CONCLUSIONS

Application of topical MMC is an efficient treatment for residual conjunctival SCC. Longer follow-up is required to confirm these findings.

Traumatic wound dehiscence after cataract extraction

PURPOSE

To study the visual outcome and factors associated with it in patients with traumatic dehiscence of a cataract surgery wound.

SETTING

Department of Ophthalmology and the Brown School of Public Health and Community Medicine, The Hebrew University-Hadassah Medical School, Jerusalem, Israel.

METHODS

A retrospective observational study of 37 eyes of 37 consecutive patients with traumatic wound dehiscence of a cataract surgery wound was conducted. A complete ophthalmic evaluation was performed in all patients. Statistical analysis was done to identify factors associated with the best corrected visual acuity at the end of follow-up.

RESULTS

Patients had extracapsular cataract extraction (n = 29), intracapsular cataract extraction (n = 4), or lensectomy (n = 4). No patient had phacoemulsification via a small incision. A univariate analysis showed that factors associated with a worse visual outcome included the presence at presentation of hyphema (P = .05), intraocular lens dislocation or loss (P = .006), vitreous hemorrhage (P = .0002), scleral rupture (P = .001), a long interval from surgery to trauma (P < .0001), and fall as the cause of trauma (P < .0001). In a multivariate model, only a surgery-to-trauma interval longer than 8 weeks was associated with a worse visual outcome (P < .0001). Visual acuity immediately after trauma was a poor predictor of final visual acuity.

CONCLUSIONS

Visual outcome after traumatic wound dehiscence of a cataract surgery wound was strongly associated with the interval from surgery to trauma. Other factors were less reliable predictors of visual outcome. Traumatic wound dehiscence only moderately affected visual outcome after cataract surgery in most cases.

Proliferative activity and p53 expression in primary and recurrent pterygia

PURPOSE

To assess p53 expression and proliferative activity in primary and recurrent pterygia from the same eyes.

DESIGN

Retrospective comparative human tissue study.

PARTICIPANTS

Tissue from excised primary pterygia that did not recur (group A, n = 10) was compared with tissue from primary pterygia that recurred (group B, n = 10) and to the recurrent pterygia tissue that was excised from subjects in group B (group C, n = 10). Ten normal conjunctivas served as controls (group D).

METHODS

Sections from each pterygium were immunostained with the MIB-1 and bp53. 12 monoclonal antibodies that react with Ki-67 and p53 antigens, respectively.

MAIN OUTCOME MEASURES

Proliferative activity was calculated as the mean of the MIB-1 positive cell count per eyepiece grid in high magnification (x40) (positive cell count/grid). Percentage of positive cells of all cells in the grid area was evaluated in the p53-stained sections.

RESULTS

Proliferative activity was found in the epithelium overlying the pterygia and normal conjunctiva. The mean MIB-1 positive cell count/grid +/- standard error was 2.84 +/- 1.07, 1.74 +/- 0.82, 3.83 +/- 1.35, and 0.86 +/- 0.33 in groups A, B, C, and D, respectively (P = 0.17, Kruskal-Wallis). P53 staining was found in 50% of pterygia in groups A, B, and C; none of the normal conjunctival tissues showed p53 immunoreactivity. Four of five p53-positive tissues in group B were p53-negative in group C. In the p53-positive pterygia, less than 10% of cells were p53 positive. However, p53-positive pterygia had higher mean MIB-1 positive cell count/grid +/- standard error as compared with the p53-negative lesions, 4.56 +/- 0.94 vs 1.39 +/- 0.59 (P = 0.021, Mann-Whitney).

CONCLUSIONS

p53 immunoreactivity and high proliferative activity in the epithelium overlying the pterygium are not associated with recurrence of pterygium.

Immunostaining of the estrogen receptor in conjunctival primary acquired melanosis

Conjunctival primary acquired melanosis (PAM) is a frequent precursor of conjunctival melanoma. Since there is indirect evidence that the conjunctiva is an estrogen-responsive tissue, and since it was suspected that estrogen has a role in the etiology of melanoma, we decided to evaluate whether PAM may be responsive to estrogen. Formalin-fixed, paraffin-embedded sections from 13 cases of PAM and 2 cases of conjunctival melanoma were immunostained with an estrogen-receptor (ER)-specific antibody. All lesions and the normal conjunctival tissue adjacent to the lesions were found to be ER negative. It is concluded that PAM and normal conjunctiva are not sensitive directly to estrogen. When considering previously reported data, it is conceivable that the normal conjunctiva, but not PAM, is indirectly affected by estrogen.

Conjunctival fibroblasts enhance the survival and functional activity of peripheral blood eosinophils in vitro

PURPOSE

To examine the effect of human conjunctival fibroblasts on the survival and functional activity of human peripheral blood eosinophils.

METHODS

Eosinophils were purified by negative immunoselection [magnetic activated cell sorter (MACS), purity > 97%] from volunteers with mild atopia. Fibroblasts were cultured from conjunctival specimens of healthy donors. Eosinophils were cultured on confluent monolayers of conjunctival fibroblasts or in culture medium alone. Eosinophil survival was evaluated by the trypan blue exclusion test. Eosinophil adherence was assessed by counting the attached cells after washing the cultures. Eosinophil viability and adherence in coculture were also assessed in the presence of anti-granulocyte-macrophage colony-stimulating factor (GM-CSF), anti-interleukin (IL)-3, and anti-IL-5 neutralizing antibodies. Cocultured eosinophils were activated by lipopolysaccharide (LPS) after 4 days in culture, and eosinophil peroxidase (EPO) release was determined as a marker of their activation.

RESULTS

Eosinophils cocultured with conjunctival fibroblasts had a significantly increased viability of 35.9% (P = 0.004) and 12.8% (P = 0.003) on days 4 and 8, respectively. Fibroblast-conditioned medium did not enhance the survival of eosinophils. The increase in eosinophil survival in coculture was partially inhibited by anti-GM-CSF (P = 0.019), anti-IL-3 (P = 0.033), or anti-IL-5 (P = 0.011), whereas eosinophil adherence was reduced by anti-GM-CSF alone (P = 0.034). LPS activation of eosinophils cultured for 4 days with conjunctival fibroblasts induced higher EPO release than in freshly isolated eosinophils (P = 0.01).

CONCLUSIONS

Human conjunctival fibroblasts induced prolonged survival and increased secretory function of human peripheral blood eosinophils. Increased survival is partially mediated by IL-3, IL-5, and GM-CSF. The coculture of conjunctival fibroblasts with eosinophils can serve as an in vitro system for the study of eosinophil behavior in the ocular surface and of cellular interactions in allergic eye diseases.

Treatment of conjunctival intraepithelial neoplasia with topical drops of mitomycin C

PURPOSE

To evaluate the efficacy and risks of complications of topical mitomycin C (MMC) for small-size conjunctival intraepithelial neoplasia (CIN).

METHODS

Eight patients with clinically diagnosed CIN <8 mm were included in the study. Patients received topical drops of MMC, 0.02-0.04%, 4 times daily for 14 days. Retreatment was done when lesions were not eliminated or recurred after the first treatment.

RESULTS

Three patients remained disease free after one course of MMC application. Retreatment was done in four patients because of lesions that decreased in size but were not eliminated, and for regrowth in one case. After retreatment, the lesions were eradicated in four patients, whereas in one patient, the treatment failed, and the lesion was surgically excised. The complications of MMC use included mild conjunctival hyperemia in two patients and mild allergy in one patient, which resolved after discontinuation of the treatment.

CONCLUSION

Application of topical MMC is an effective treatment for most but not all cases of small-size CIN.

Neurotrophic corneal endothelial failure complicating acute Horner syndrome

PURPOSE

The authors report the clinical findings of a unique case of rapid corneal endothelial decompensation in association with acute Horner syndrome.

STUDY DESIGN

Case report and literature review.

METHODS

The authors followed a 38-year-old woman who developed Horner syndrome after right jugular vein catheterization during cardiac valvular surgery. Shortly after the operation, Horner syndrome accompanied by conjunctival hyperemia and stromal corneal edema developed in the right eye. Over the course of 4 months, the eye became painful, the corneal endothelial cell count dropped precipitously, and the stromal edema worsened, causing a difference of 100 microm in central corneal thickness compared to the unaffected eye. Deep stromal vascularization started at the limbus, resembling interstitial keratitis.

RESULTS

A 3-week course of topical steroid treatment resulted in a dramatic improvement in the stromal corneal edema and regression of the deep stromal vascularization. Ocular and right hemicranial pain subsided shortly thereafter.

CONCLUSION

The authors hypothesize that corneal endothelial failure in this unique case may have resulted from traumatic sympathectomy. According to experimental evidence in the reviewed ophthalmologic literature, sympathetic innervation may have a neurotrophic role in the cornea. Corneal pathology similar to the authors' case has been described in hemifacial atrophy (Parry-Robson syndrome), a disorder that is assumed to result from sympathetic denervation and that can be produced in animals by cervical sympathectomy. The authors therefore hypothesize that sympathetic denervation of the cornea may rarely cause endothelial decompensation and corneal edema. To the authors' knowledge, this is the first reported case of corneal endothelial failure in Horner syndrome.

Late-onset, bleb-associated endophthalmitis following glaucoma filtering surgery with or without antifibrotic agents

The use of adjunctive antimetabolites such as 5-fluorouracil (5-FU) and mitomycin C (MMC) in trabeculectomy has caused an increased concern as to the risk of bleb-associated endophthalmitis. In this study, we compared the incidence of this complication between different methods of adjunctive treatment in glaucoma filtering surgery. Records of 15 cases of late-onset, bleb-associated endophthalmitis which were admitted to the Ophthalmology Department, Hadassah University Hospital, between January 1980 and December 1997 were retrospectively studied. These patients had endophthalmitis at least two months following glaucoma filtering surgery. Bleb-associated endophthalmitis occurred in 2 eyes following filtering surgery with no antifibrotic agent, in 6 eyes following trabeculectomy with 5-FU, and in 7 eyes that underwent trabeculectomy with intraoperative MMC. The mean time from surgery to endophthalmitis following 5-FU was 25.0+/-22.0 months (range 3 to 56 months), and 11.3+/-5.4 months (range 4 to 18 months) following the use of MMC. The estimated cumulative incidences of bleb-associated endophthalmitis in superior blebs at 24 months following surgery were 0.3% for surgeries without antifibrotic agents, 0.8% for trabeculectomies with postoperative 5-FU, and 1.3% for trabeculectomies with intraoperative MMC. No significant differences were demonstrated between the survival distributions of filtering procedures performed with any of the three techniques (p = 0.166, Log-rank test). Most of the cases following 5-FU or MMC appeared within 18 months following trabeculectomy. The visual outcome of most of the eyes was poor. Antifibrotic agents are not associated with a higher risk for late-onset, bleb-associated endophthalmitis. A high rate of alertness is warranted for diagnosis of early signs of infection following glaucoma filtering surgery.

Corneal dynamics after single interrupted suture removal following penetrating keratoplasty

PURPOSE

To evaluate corneal topographic changes after removal of a single interrupted suture in patients who underwent keratoplasty for keratoconus.

METHODS

Fifteen interrupted sutures in 15 eyes after keratoplasty were removed to control astigmatism in a prospective clinical study. Videokeratography using an EyeSys Corneal Analysis System was performed before suture removal, and 1 hour, 1 day, 1 week, and 2 to 4 weeks after suture removal. Changes in dioptric power and axis of the steepest and flattest semimeridians were evaluated.

RESULTS

The range of the dioptric change of the steepest semimeridian was from -0.43+/-0.34 D during the first hour to +0.70+/-0.39 D from 1 day to 1 week. The largest axis change of the steepest semimeridian (17.1 degrees+/-5.6 degrees, range 1 degree to 66 degrees ) occurred during the first hour (P = .006). The largest surgically induced vectorial change occurred during the first hour (16.10 @ 10.5 ), while relative stability of the steepest semimeridian was observed during the rest of the study period. Changes in power and axis of the flattest semimeridian were also demonstrated. A variety of topographic corneal patterns were demonstrated following suture removal, indicating unpredictable change of astigmatism.

CONCLUSIONS

The steepest semimeridian of the central 3-mm zone showed maximal vectorial change 1 hour following suture removal. Reciprocal changes occurred at the same time in the flattest semimeridian. The response of the corneal surface to suture removal is unpredictable and complex.

The distribution of gentamicin in the rabbit cornea following iontophoresis to the central cornea

The purpose of this study was to evaluate the penetration of gentamicin into the central, midperipheral and peripheral cornea of rabbits following iontophoresis to the central 3 mm of the cornea. Four groups (groups 1-4) of five rabbits (one eye per rabbit) underwent corneal iontophoresis using gentamicin dissolved in agar. Low (1 mg/ml) and high (10 mg/ml) concentrations of gentamicin in agar were used for one or ten minutes. Two control groups (groups 5 and 6) of five eyes each underwent mock iontophoresis with low and high concentrations of agar-gentamicin mixture. Following sacrifice of the rabbits, the central, midperipheral and peripheral parts of each cornea were excised. Gentamicin concentration was determined in each part of every cornea. High concentrations of gentamicin (951.6 +/- 369.4 microg/ml to 26.6 +/- 41.34 microg/ml) were obtained in the central parts of all the iontophoresis-treated corneas. In each group, except group 6, central corneas had higher concentrations of gentamicin compared to midperipheral corneas (p = 0.038 to p = 0.021), and midperipheral corneas had higher levels than peripheral corneas (p = 0.038 to p = 0.021). Following iontophoresis, gentamicin is found in all portions of the corneas; however, the highest concentration of the drug remains in the central cornea.

Relaxing incision guided by videokeratography for astigmatism after keratoplasty for keratoconus

PURPOSE

To evaluate the efficacy of topographic measurements for relaxing incisions in astigmatism following penetrating keratoplasty for keratoconus.

METHODS

Twenty patients (20 eyes) had relaxing incisions between July 1989 and August 1994 for high astigmatism after penetrating keratoplasty for keratoconus. Ten eyes were evaluated using a HaagStreit keratometer (1989-1991) and 10 eyes were evaluated using EyeSys videokeratography (1991-1994). Relaxing incisions were performed at the steep meridians in the donor/host wound.

RESULTS

Mean preoperative astigmatism was 7.75 +/- 2.05 D (range, 4.50 to 12.00 D) for the keratometry group, and 6.49 +/- 3.24 D (range, 1.11 to 10.13 D) for the videokeratography group. Mean astigmatism following relaxing incision was 3.90 +/- 2.02 D (range, 0.93 to 6.50 D) for the keratometry group and 3.06 +/- 1.62 D (range, 0.07 to 5.64 D) for the videokeratography group (no significant difference). Vector analysis revealed a vectorial change of 4.64 +/- 2.54 D for the keratometry group and 4.68 +/- 2.08 D for the videokeratography group (no significant difference). Mean spectacle-corrected visual acuity was significantly improved in the topography-guided group following the procedure (P = .021). Complications included perforations in 3 of 20 eyes. Four patients (4 eyes) in the keratometry group and one patient (1 eye) in the videokeratography group had residual astigmatism greater than 5.00 D. Four patients in the keratometry group needed a second procedure of relaxing incision because of irregular (2 eyes) or high (2 eyes) astigmatism. One patient (1 eye) in the videokeratography group needed a second relaxing incision.

CONCLUSIONS

Videokeratography as a guide for relaxing incision has some benefits over standard keratometry. Preoperative evaluation with videokeratography did not significantly improve the postoperative astigmatism. Fewer reoperations were needed when videokeratography was used.

Topical indomethacin solution versus dexamethasone solution for treatment of inflamed pterygium and pinguecula: a prospective randomized clinical study

PURPOSE

To compare the effect of topical indomethacin 0.1% solution with the effect of topical dexamethasone 0.1% phosphate solution on signs and symptoms of inflamed pterygium and pinguecula.

METHODS

Of 50 consecutive patients who had inflamed pterygia (n = 17) or pingueculae (n = 33), met the study criteria, and signed an informed consent, one eye of each patient was evaluated in a comparative, prospective, randomized, double-masked, controlled study. Objective signs (conjunctival congestion, redness and edema, and staining of cornea) and subjective complaints (photophobia, pain, foreign-body sensation, discomfort, and tearing) were evaluated and scored. We also evaluated "total signs," "total symptoms," and "total score." Group 1 (n = 25) received topical indomethacin 0.1% solution, and group 2 (n = 25) received a topical dexamethasone phosphate 0.1% solution six times daily for 3 days, then four times daily over the following 11 days. Patients were examined before treatment, on days 3, 7, and 14 after the treatment was initiated, and 2 and 4 weeks after the treatment was discontinued.

RESULTS

In both groups, the scores for "total signs," "total symptoms," and "total score" were significantly lower (P = .001) by day 14. There were no differences between groups 1 and 2 for "total signs," "total symptoms," and "total score" at days 3, 7, and 14 (P = .07 to P = .88). After treatment was discontinued, the dexamethasone-treated group experienced a significantly greater recurrence of "total signs" (P = .023 at day 30, P = .02 at day 45), but there was no statistically significant difference in "total symptoms" and "total score." Patients in group 2 reported more stinging after drops were administered than patients in group 1 (P = .002).

CONCLUSIONS

This study indicates that topical indomethacin 0.1% solution is as effective as topical dexamethasone phosphate 0.1% solution for the treatment of inflamed pterygium and pinguecula and, therefore, is suggested as an effective treatment for these conditions.

Evaluation of a positively charged submicron emulsion of piroxicam on the rabbit corneum healing process following alkali burn

The effect of piroxicam in three different formulations was tested on rabbits for 28 days in an alkali burn model. The ulceration healing process was determined by evaluating the severity of the burn (scored from 0 to 5), and the re-epithelization healing process was measured by the area of the defects. The results indicated that the piroxicam positively charged submicron emulsion was the most effective formulation in lowering the ulcerative cornea score while the piroxicam positively charged emulsion and the blank emulsion were more effective in promoting the re-epithelization healing process. The piroxicam solution elicited the slowest healing re-epithelization rate after 28 days and was unable to complete the entire healing process. The new positively charged submicron emulsion formulation of piroxicam had a pronounced effect on both the ulceration rate and epithelial defects in the management of corneal alkali-burning.