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Purpose: To present a case of Maroteaux-Lamy syndrome (MLS, mucopolysaccharidosis [MPS] type VI) who underwent bone marrow transplantation (BMT) for gene transfer at the age of 13, and penetrating keratoplasty at the age of 17, and maintained clear corneal grafts bilaterally for 13 years. To our knowledge, this is the longest follow-up reported on corneal graft survival in a patient with MLS and BMT., Methods: In 1982, BMT was successfully performed on a 13-year-old girl with MLS with growth retardation, typical facial features, skeletal and joint deformities, hepatosplenomegaly, cardiopulmonary dysfunction, and corneal clouding. Corneal transplantation was done on the left eye in 1986, and on the right eye in 1987 (6 months later) without difficulty or complication., Results: Thirteen years postoperatively, the patient was systemically well, and both eyes retained clear corneal grafts., Conclusion: BMT retarded further dysfunction from MLS, and the corneal transplants retained clarity. Further controlled studies with longer follow-up are required to establish the efficacy of BMT in ocular manifestations of MPS or MLS.

Purpose: Reactivation of latent herpes simplex virus (HSV) by excimer laser photorefractive keratectomy(PRK) has been reported previously in the literature. This study evaluates the extent of such HSV reactivation and determines whether corneal de-epithelialization prior to PRK or the laser treatment itself induces this response., Methods: Twenty three normal 1.5-2.5 kg New Zealand white rabbits were infected on the surface of the cornea with HSV-1, strain RE. The animals were monitored until resolution and then divided into two treatment groups: 1) de-epithelialization alone, and 2) de-epithelialization plus laser. Animals were evaluated in a masked fashion by clinical examination and viral cultures twice a week through day 28., Results: The reactivation rate for group 1 (de-epithelization alone) was 0.0%, and for group 2 (PRK) was 67% by slit lamp biomicroscopy. Viral culture positivity rate matched these findings., Conclusions: Excimer laser (193 nm) treatment can trigger viral shedding and reactivation of herpetic ocular disease in the latently infected rabbit. De-epithelialization alone is not sufficient to cause such viral reactivation or keratitis. Our findings suggest that patients with a history of herpetic keratitis undergoing PRK are at increased risk of HSV reactivation as a result of exposure to the excimer laser.

Purpose: To compare the keratometric readings obtained from Intraoperative PAR Corneal Topography System (IOPAR) to those produced by manual keratometer (Mnl-Km), autokeratometer (Auto-Km), EyeSys CAS (EyeSys Corneal Analysis System) and slit lamp PAR CTS in healthy eyes., Methods: All instruments were calibrated prior to use and only data from the best image obtained was used for statistical analysis. Simulated keratometry readings obtained from the central 3-mm zone of the corneas by IOPAR, including flat (K1) and steep (K2) keratometry readings, average keratometric power (AK), astigmatism (As) (difference between steep and flat keratometry readings) and the axis of the steep meridian (Ax) were compared to those from four other units. The latter units were also compared among themselves. Statistical analysis was done for right and left eyes separately. For each variable, average differences between the measurements taken from pairs of instruments were estimated, with corresponding 95% confidence intervals. The degree of agreement between pairs of instruments on individual measurements was additionally assessed, via the use of "Bland-Altman"-type plots, and estimates of the proportion of cases achieving satisfactory agreement. Additionally, for every variable, the average of the measurements taken from the different instruments were compared., Results: Forty-five (22 right and 23 left) normal corneas of 26 volunteers were examined. On the average, IOPAR tended to measure K1 higher than slit lamp PAR CTS system. Because K2 measurements taken by the IOPAR were higher than that of all other instruments, the As measurements, on the average, were also higher than that of others, with the exception of the PAR CTS. For the same reasons, the IOPAR produced average AK readings that were higher than those taken by EyeSys CAS and PAR CTS. When the individual measurements taken by the IOPAR were compared with each of the other units, according to the arbitrary designation of satisfactory agreement within +/-0.5 D (for K1, K2, AK, and As) and +/-20 degrees (for Ax), for almost all parameters, proportion of differences that were within the agreement range varied from 0.33 to 0.82, with wide confidence intervals (confidence interval lower limits ranging from 0.20 to 0.61 and upper limits ranging from 0.62 to 0.94)., Conclusions: IOPAR is a clinically useful topographic system, producing qualitative and quantitative data in the operating environment that, in normal corneas, on the average, matches those produced by the other units in the clinic. When individually analyzed, its keratometric measurements may show greater variations with respect to other units. Further studies with multiple examiners, in corneas with high or irregular astigmatism are required to establish its reproducibility and efficacy.

Purpose: To evaluate the usefulness of measuring corneal topography intraoperatively by Intraoperative PAR Corneal Topography System (IOPAR CTS) to predict the postoperative topographical changes in patients undergoing refractive surgery., Methods: Topographical measurements of 9 eyes of 9 patients were taken by IOPAR CTS: 6 immediately after Intrastromal Corneal Ring Segments (ICRS) placement surgery and 3 immediately after Photorefractive Keratectomy (PRK) surgery. The topographical images taken by IOPAR CTS were analyzed to determine the quality of the image produced and the correlation of the keratometric data from the central 3 mm of cornea with measurements taken from an autokeratometer (Auto-Km) and the EyeSys Corneal Analysis System (CAS) for the same eyes taken three months following the procedure., Results: At the 3-month postoperative exam, the correlation coefficients for flat (K1), steep (K2), and average keratometry (AK) readings produced by the Auto-Km and the EyeSys CAS were quite high. However, the correlation coefficients for K1, K2, AK, As or steep meridian axis (Ax) readings taken intraoperatively by IOPAR CTS were quite low when compared to the readings taken by either the Auto-Km or EyeSys CAS three months postoperatively., Conclusion: We found IOPAR CTS, relatively difficult to perform in the operating room during refractive surgical procedures and not useful clinically in predicting the postoperative topographical changes induced by ICRS or PRK procedure. Further studies are required to establish the efficacy and reproducibility of the instrument.

Purpose: Assessment of the characteristics of the myopic patient population applying for refractive surgery in order to determine the potential market for myopic refractive surgery., Methods: Records of consecutive patients who responded to an advertisement for refractive surgery to correct myopia were evaluated retrospectively with regards to patient demographics and the amount and distribution of the refractive error. Data were compared to that available from population-based statistics for distribution of myopia in the general population. For statistical analysis, one sample Student's t-test and two tailed Student's t-test were utilized., Results: Two hundred fifty seven patients (140 women and 117 men) responded to an advertisement for refractive surgery during the six month period between January and June 1998. Mean spherical equivalent (SEQ) of the patient population was -4.59+/-2.54 D (min;-0.25 D, max;-15.75 D) right eye (OD) and -4.62+/-2.82 D (min;-0.25 D, max;-15.25 D) left eye (OS). Among the patients who had myopia with an astigmatism of at most 1.00 D (n=165), the distribution of refractive error was statistically significantly different from that obtained from population-based statistics, such that, although most of the myopic population (40%) had an SEQ of -1.00 to -2.25 D, the majority of our patients (54.8%) who applied for myopic refractive surgery had an SEQ of -2.50 to -5.00 D. Another striking difference was that, although patients with an SEQ more than -6.00 D were a minority(2%) in the population study, in our study group, they comprised 16.7% of the patients seeking refractive correction. The difference between the SEQ of the right and left eyes ranged from 0.00 D to 13.0 D (mean, 0.89+/-1.5 D), 47.1 % having a difference of at most +/-0.5 D between the two eyes. The mean cylindrical error in the patient population was 0.69+/-0.93 D (min: 0, max: -4.5) OD and 0.69+/-0.96 D (min: 0, max: -4.5) OS. There were no statistically significant differences between the distribution of SEQ or cylindrical refractive error between males and females., Conclusion: Although a population-based study reported that most of the myopic population (40%) had an SEQ of -1.00 to -2.25 D, the majority of our patients (54.8%) who applied for myopic refractive surgery had an SEQ of -2.50 to -5.00 D. On the other hand, while patients with an SEQ of -6.00 D and more constituted only about 2% of the general population, they accounted for 16.7% of our study population. Therefore, the refractive characteristics of the patient population applying for myopic refractive surgery may not necessarily parallel that of general population-based statistics. In order to establish a more effective refractive surgery practice, it is feasible to perform local studies and reevaluate the requirements of your practice accordingly.

Purpose: To evaluate the safety and effectiveness of loteprednol etabonate 0.5% ophthalmic suspension (LE) for reducing the ocular signs and symptoms accompanying contact lens associated giant papillary conjunctivitis (GPC). We conducted a randomized, double-masked, placebo-controlled, parallel study at 11 U.S. academic or private practice clinics., Methods: Two hundred and twenty adults with contact lens associated GPC were enrolled in this study. Patient were treated with either LE or the loteprednol etabonate vehicle (placebo), q.i.d. for 6 weeks. Papillae, itching, lens intolerance, as well as other signs and symptoms of GPC (0 to 3 or 0 to 4 point severity scales), and intraocular pressure were measured., Results: The proportion of patients treated with LE demonstrating an improvement in papillae of at least one grade (75%) was significantly greater than the proportion of those treated with placebo (50%, P < 0.001). A treatment difference favoring LE was also seen with improvement in itching (92% vs. 76%, P = 0.001) and lens intolerance (84% vs. 66%, P = 0.002). Three patients (all on LE) had an intraocular pressure (IOP) elevation of 10 mm Hg or higher from baseline on at least one on-treatment visit. Cessation of therapy was required in one of these patients., Conclusions: Both treatments were well tolerated and no serious, unexpected, treatment-related medical events were reported. The rapid therapeutic response, combined with the low incidence, late development, and transient nature of any IOP elevation suggests that LE may be helpful in treating GPC.

Purpose: A direct mail survey of residents and young practitioners in ophthalmology was undertaken to assess the extent and effectiveness of residency training relating to contact lenses., Methods: The respondents, 135 residents and 124 young practitioners, represented 117 of the 128 residency programs in the United States. The questionnaire dealt with issues including respondents' sources of information about contact lenses during and after residency, the residency years in which they received contact lens training, the frequency and length of clinic sessions dealing with contact lenses, the number and types of patients they saw, and the number and training of their clinic supervisors. In addition, the questionnaire elicited respondents' ratings of their total residency programs and their specific training with regard to contact lenses and their degree of confidence in dealing with lens-related problems., Conclusions: The results of this survey indicate that residency programs take no consistent approach to contact lens training and are not adequately preparing ophthalmologists to deal with the fitting and management of contact lenses or problems relating to their wear.

We evaluated a new integrated contact lens care system that combines fluid turbulence for lens cleaning with ultraviolet (UV) light for solution sterilization. The ultraviolet light system was used to clean and disinfect 42 soft contact lenses (water contents: 38.6%, 43%, 55%, and 70%) and two rigid gas permeable lenses. Test lenses were contaminated with 10(6) cells/mL of Bacillus pumilus, Aspergillus niger, Pseudomonas aeruginosa, and Acanthamoeba castellanii and subjected to a 15-minute cleaning-disinfection cycle. Bathing solutions and contact lenses were cultured at various time intervals and at the end of the cycle. All bathing solutions and all lenses but one were found to be sterile after one cycle. All units effectively disinfected solutions and contact lenses. This device may be an effective alternative to existing contact lens care systems.

We used high-frequency ultrasound B-scanning with digital signal processing for pachymetric analysis of corneal scars to help determine the optimal management strategy. Four patients were selected for this report. By an automated motor system, 12 consecutive, parallel ultrasound B-scans, each 2.5 to 3 mm wide at 0.25 mm intervals, were obtained from the central corneal area of three patients with anterior corneal scarring. In a fourth patient with near complete corneal scarring obscuring the view of the anterior chamber, a set of 15 mm wide B-scans was obtained. Digitized ultrasound signals were used to produce high-resolution images and I-scans enabling a pachymetric precision of +/- 2 microns (SD). Epithelial, scar, and corneal thickness measurements were made along each scan to determine the most significant zone of pathology. Pachymetry of the cornea and the individual layers was used to assess the suitability for either photorefractive or penetrating keratectomy. B-scan imaging of the full anterior segment provided useful information for the preoperative planning of anterior segment reconstruction and the prognostic evaluation of penetrating keratoplasty. This method provides a powerful tool for the corneal surgeon in management planning.

Purilens is a new contact lens care system that uses ultraviolet light and subsonic turbulence for lens cleaning and disinfection. In a single hands-off process using only preservative-free sterile saline, the lenses are ready to wear after a 15-minute cycle. This study was designed to test the safety of this contact lens care system. A total of 84 contact lens wearers from six centers were enrolled in the 3-month study, which comprised an initial visit and follow-up visits at 1, 2, 4, 8, and 12 weeks. At the end of the study, lenses and units were collected and a questionnaire was completed. Seventy-six of the 84 subjects (168 eyes) completed the study. No severe eye complications were reported, and no patients were removed from the study because of ocular problems or complications associated with the device or its use. Four patients were removed from the study for noncompliance with follow-up. Another four patients were active for 2 months, but were requested by the sponsor to complete the study 1 month early to complete data collection. Patient satisfaction was high. The study suggests that Purilens may be considered as an alternative for contact lens cleaning and disinfection.

We used Becker and Maiman's Health Belief Model to study the compliance of 100 disposable contact lens patients using a recommended lens care routine. Compliance was defined as continuous lens wear for no more than two consecutive weeks. A telephone survey found 90 of 100 patients to be complaint. Unexpectedly, 62% of patients removed and then reinserted the same pair of lenses. No significant difference was found between the complaint and noncompliant groups with respect to their health beliefs. Seven percent of the patients reported having experienced corneal complications and 8% reported eye infections. However, a review of these patients' charts showed that only 3% had been diagnosed as having corneal abrasions, and none had been diagnosed as having an eye infection.

We conducted a retrospective assessment of the fitting characteristics obtained with the Boston Envision rigid gas permeable contact lens to determine the best parameter for selecting an initial base curve. We fit 13 subjects (11 successfully) with the Envision lens, using computerized videokeratoscopy to evaluate prefitting corneal topography. The selected base curve of the lenses fit most closely to the flattest K at the 5 mm zone. This value may be the best parameter for selection of an initial base curve, especially in eyes with keratoconus. Using topographic information may give quicker and more accurate initial fits than keratometry alone.

The incidence of corneal infections among the almost 20 million Americans who wear contact lenses, while still small, is rising rapidly. Patient non-compliance with instructions for proper lens care is partly at fault. The general phenomenon of patient non-compliance has been widely studied, most often by using the Health Belief Model (HBM). We report here on 50 consecutive patients fit with contact lenses by one ophthalmologist who were questioned by telephone regarding their lens care practices and beliefs. Forty-four percent of this group wore contact lenses for therapeutic reasons; the remainder wore them for either cosmetic reasons (34%) or convenience (22%). Adherence to published lens care guidelines was used as a basis for segregating patients into a compliant and a non-compliant group. By the criteria selected, 46% of the sample was non-compliant in their lens care. An analysis of responses from each group was structured in terms of HBM dimensions. Our aim was to determine whether there were differences in the beliefs held by compliant vs. non-compliant patients. Age under 30 and obtaining lenses for cosmetic or convenience reasons were the two variables statistically associated with non-compliant behavior. At least one undesirable belief representing each of the four HBM dimensions was found to be positively correlated with non-compliant lens use. The HBM is an effective model with which to investigate the relationship between non-compliant behavior and the rise in contact lens-related complications.

Corneal curvature was evaluated in 70 children by central keratometric measurements. The mean keratometric reading in each age group was seen to decline systematically from birth to about 54 months of age. The mean in the newborn-to-6-month-old group was 47.59 D; in the 12-18-month-old group it had decreased to 45.56 D. The cornea appears to stabilize at about 54 months, with an average reading of 42.69 D. Evaluation of 11 eyes diagnosed as having persistent hyperplastic primary vitreous revealed that eyes with this diagnosis generally have steeper corneas than normal eyes at any given age.

Nine ophthalmologists and nine optometrists conducted a premarket study of the Acuvue disposable contact lens manufactured by Vistakon, Inc. Of the 812 patients offered the lens, 733 accepted it and were enrolled in the study. These patients were fitted with the lens and followed for a period of 8 months. Over 98% of these patients had 20/25 or better vision on initial fitting; and subjective ratings of lens comfort were very good. Only 3.7% (27 of 733) discontinued wearing their lenses during the study period. Thirty-four patients (5.6%) experienced a problem while wearing their contact lenses.