Boston Type 1 Keratoprosthesis: Visual Outcomes, Device Retention, and Complications.

PURPOSE: To determine the visual outcomes, device retention, and complications after Boston type 1 keratoprosthesis (KPro-1) device implantation. METHODS: Comprehensive review of every case of KPro-1 implantation at a tertiary eye care center. RESULTS: The initial KPro-1 procedure, performed in 75 eyes without a previous keratoprosthesis, was included in the analysis. During the first 6 postoperative months, improvement occurred in the mean preoperative best-corrected visual acuity of 20/1265 to a mean best-obtained postoperative visual acuity of 20/97 (P < 0.001). After a mean follow-up period of 41.4 months (range, 0.8-82.8 months), the final mean best-corrected visual acuity was 20/428. Improved vision was recorded in 43 eyes (57.3%), ambulatory vision (≥20/400) in 47 eyes (62.7%), intermediate functional vision (≥20/80) in 23 eyes (30.7%), and full functional vision (≥20/40) in 11 eyes (14.7%). The initial device was retained in 64 eyes (85.3%), with a Kaplan-Meier retention probability of 96% at 6 months and 82% at 5 years. One or more sight-threatening complications occurred in 51 eyes (68%). These included device extrusion in 11 eyes (14.7%), ulcerative keratitis in 12 eyes (16%), endophthalmitis in 7 eyes (9.3%), sterile vitritis in 3 eyes (4%), retroprosthetic membranes in 25 eyes (33.3%), maculopathy in 26 eyes (34.7%), retinal detachment in 9 eyes (12%), and progressive optic neuropathy in 7 eyes (9.3%). CONCLUSIONS: Boston KPro-1 implantation is associated with satisfactory visual outcomes and excellent device retention in a majority of cases. However, serious postoperative complications are common and may compromise the final visual result.

Boston type 1 keratoprosthesis for failed keratoplasty.

The purpose of this study was to evaluate the outcomes of the Boston type 1 keratoprosthesis (Kpro-1) in eyes with failed keratoplasty. A retrospective review was performed of every patient treated with a Kpro-1 at a tertiary eye care center between January 1, 2008 and July 1, 2013. Eyes with a failed keratoplasty originally performed for corneal edema, trauma, or keratoconus were included in the statistical analysis. The main outcome measures were visual outcome, prosthesis retention, and postoperative complications. Twenty-four eyes met the inclusion criteria, including 13 eyes with corneal edema, 8 eyes with trauma, and 3 eyes with keratoconus. After a mean follow-up period of 28.9 months (range 7-63 months), the median best corrected visual acuity (BCVA) was 20/125. The BCVA was ≥ 20/40 in 4 (16.7 %) eyes, ≥ 20/70 in 9 (37.5 %) eyes, and ≥ 20/200 in 14 (58.3 %) eyes. Overall, the postoperative BCVA improved in 17 (70.9 %) eyes, was unchanged in 3 (12.5 %) eyes, and was worse in 4 (16.7 %) eyes. The initial Kpro-1 was retained in 22 (91.7 %) eyes, and was successfully repeated in the other 2 eyes. One or more serious prosthesis- or sight-threatening complications occurred in 8 (33.3 %) eyes. These included 1 case of wound dehiscence leading to prosthesis extrusion, 1 case of fungal keratitis leading to prosthesis extrusion, 4 cases of endophthalmitis, and 5 retinal detachments. The Boston Kpro-1 is associated with an excellent prognosis for prosthesis retention and satisfactory visual improvement in eyes with previous failed keratoplasty.

Treatment of acanthamoeba keratitis with intravenous pentamidine before therapeutic keratoplasty.

PURPOSE: The aim of this study was to evaluate the outcome of pretreatment of Acanthamoeba keratitis with intravenous pentamidine (IVP) before therapeutic keratoplasty (TKP). METHODS: A retrospective chart review was performed of the medical records of every patient treated with IVP before TKP for Acanthamoeba keratitis at a single, tertiary care eye center between January 1, 2002, and December 31, 2012. The main outcome measures were microbiological cure, graft survival, and visual outcome. RESULTS: Eight eyes of 7 patients met the inclusion criteria. Preoperatively, all 8 eyes had failed traditional antiamoebic therapy, including 5 eyes with recurrent infections after previous TKP. The patients were treated with IVP (190-400 mg/d) for a median of 14 days (range, 7-26 days). After 8 TKP, a microbiological cure was achieved, and a clear graft was maintained in 5 (62.5%) eyes during a mean follow-up interval of 31.2 months (range, 1.0-95.7 months). Repeat TKP in 3 eyes with recurrent Acanthamoeba keratitis resulted in 2 additional microbiological cures and 1 more clear graft. The final best-corrected visual acuity was ≥20/40 in 5 (62.5%) eyes and worse than 20/200 in 3 eyes. Overall, the final vision was improved in 6 (75.0%) eyes, remained the same in 1 (12.5%) eye, and was worse in 1 (12.5%) eye. CONCLUSIONS: The adjunctive use of IVP before TKP may assist with the achievement of microbiological cure, clear graft, and good visual outcome in a majority of eyes with Acanthamoeba keratitis.

Diabetes mellitus increases risk of unsuccessful graft preparation in Descemet membrane endothelial keratoplasty: a multicenter study.

PURPOSE: The aim of this study was to evaluate preparation outcomes of tissue prepared for Descemet membrane endothelial keratoplasty (DMEK) from diabetic and nondiabetic donors. METHODS: In this nonrandomized, consecutive case series, DMEK grafts were prepared from diabetic and nondiabetic donors by experienced technicians in 2 eye banks using slightly different, modified submerged manual preparation techniques to achieve "prestripped" graft tissue. Graft preparation results were analyzed retrospectively. The main outcome measure was the rate of unsuccessful (failed) DMEK graft preparations, defined as tears through the graft area that prevent tissue use. RESULTS: A total of 359 corneas prepared from 290 donors (114 diabetic and 245 nondiabetic) were included in the statistical analysis of graft preparation failure. There were no significant differences between diabetic and nondiabetic donor tissue characteristics with respect to donor age, death to preservation time, death to preparation time, endothelial cell density, percent hexagonality, or coefficient of variation. DMEK tissue preparation was unsuccessful in 19 (5.3%) cases. There was a significant difference in the site-adjusted rate of DMEK preparation failure between diabetic [15.3%; 95% confidence interval (CI), 9.0-25.0] and nondiabetic donors (1.9%; 95% CI, 0.8-4.8), and the corresponding site-adjusted odds ratio of DMEK graft preparation failure in diabetic donor tissue versus nondiabetic donor tissue was 9.20 (95% CI, 2.89-29.32; P = 0.001). CONCLUSIONS: Diabetes may be a risk factor for unsuccessful preparation of donor tissue for DMEK. We recommend caution in the use of diabetic tissue for DMEK graft preparation. Further study is needed to identify what subset of diabetic donors is at risk for unsuccessful DMEK graft preparation.

Boston type 1 keratoprosthesis for chemical and thermal injury.

PURPOSE: To evaluate the outcome of the Boston type 1 keratoprosthesis (Kpro-1) in eyes with failed interventions for chemical and thermal injury. METHODS: A retrospective review was performed of every eye with chemical or thermal injury that was treated with a Kpro-1 at a tertiary eye care center between January 1, 2008 and July 1, 2013. The main outcome measures were visual outcome, prosthesis retention, and postoperative complications. RESULTS: Nine eyes met the inclusion criteria, including 7 eyes with alkali burns, 1 eye with an acid burn, and 1 eye with a thermal burn. After a mean follow-up of 40.7 months (range, 29-60 months), the median best-corrected visual acuity was 20/60 (range, 20/15 to no light perception). One eye was ≥20/20, 3 eyes were ≥20/40, and 6 eyes were ≥20/70. The initial Kpro-1 prosthesis was retained in 7 (77.7%) eyes and successfully replaced in the other 2 eyes. One or more serious complications occurred in 6 (66.7%) eyes. These included 2 cases of sterile corneal ulceration with prosthesis extrusion, 2 cases of microbial keratitis (1 bacterial and 1 fungal), 2 cases of bacterial endophthalmitis, and 2 cases of retinal detachments. These complications contributed to visual outcomes of hand motions in 2 eyes and no light perception in 1 eye. CONCLUSIONS: The Boston Kpro-1 is associated with highly satisfactory visual outcomes and prosthesis retention in most cases of severe chemical or thermal injury. Serious complications are common and may compromise the final outcome.

Graft survival versus glaucoma treatment after penetrating or Descemet stripping automated endothelial keratoplasty.

PURPOSE: The aim of this study was to assess and compare the association of glaucoma therapy with graft survival after performing penetrating keratoplasty (PKP) and Descemet stripping automated endothelial keratoplasty (DSAEK). METHODS: A retrospective chart review was performed of cases: primary PKP from January 1, 2003, to December 31, 2005, or primary DSAEK from January 1, 2006, to December 31, 2008. Eyes with a surgical indication of pseudophakic corneal edema were included in the statistical analysis. Eyes were stratified by glaucoma treatment into those with (1) no glaucoma treatment, (2) medical therapy only, or (3) surgical intervention. The main outcome measure was graft survival. RESULTS: Fifty-seven PKP-operated and 156 DSAEK-operated eyes met the inclusion criteria. After PKP and DSAEK, respectively, the 5-year Kaplan-Meier graft survival was 94.7% and 93.8% in eyes with no glaucoma treatment (P > 0.99), 93.8% and 96.3% in eyes with medical therapy only (P > 0.99), and 56.8% and 50% in eyes with surgical intervention (P > 0.99). After both procedures were performed, graft survival was significantly worse in eyes with surgical intervention compared with that in eyes with no glaucoma treatment (P < 0.0001) or in eyes with medical therapy alone (P < 0.0001). CONCLUSIONS: PKP and DSAEK have comparable graft survival in eyes without glaucoma management and in those with comparable glaucoma management.

Boston keratoprosthesis type 1 for herpes simplex and herpes zoster keratopathy.

PURPOSE: The aim of this study was to evaluate and compare the outcomes of Boston keratoprosthesis type 1 (Kpro-1) in eyes with herpes simplex virus (HSV) and herpes zoster virus (HZV) keratopathy. METHODS: A retrospective review was performed of the medical records of every patient treated with a Boston Kpro-1 at the University of Iowa Hospitals and Clinics between January 1, 2008 and July 1, 2012. Eyes with visual loss due to HSV or HZV keratopathy were included in the statistical analysis. The main outcome measures were graft retention, postoperative complications, and visual outcome. RESULTS: Nine eyes met the inclusion criteria, including 5 eyes in the HSV group and 4 eyes in the HZV group. The graft retention rate was 100% in the HSV group after a mean follow-up of 48.4 months, compared with 25% in the HZV group after 50.5 months (P = 0.048). There were 3 cases of microbial keratitis, including 2 eyes that also developed endophthalmitis, in the HZV group, compared with no cases in the HSV group (P = 0.048). There was significantly better best-corrected visual acuity at the most recent examination in the HSV group than in the HZV group (P = 0.019). All 5 HSV eyes had improved best-corrected visual acuity compared with preoperative acuity, whereas only 1 HZV eye experienced a similar result (P = 0.048). CONCLUSIONS: Kpro-1 is associated with an excellent prognosis for graft retention, acceptably low prevalence of sight-threatening complications, and highly satisfactory visual improvement in eyes with HSV keratopathy, but not in eyes with HZV keratopathy.

A Comparison of Examination Equipment Used During Common Clinical Ophthalmologic Tasks.

Background: Ophthalmologists report a high prevalence of work-related musculoskeletal symptoms, particularly of the neck and shoulders. Improving the design of equipment used in the clinical environment may reduce exposures to physical risk factors (e.g., sustained muscular exertions and non-neutral postures) associated with neck and shoulder pain among ophthalmologists. Purpose: To compare estimates of neck and shoulder muscle activity and upper arm posture during use of conventional and alternative examination equipment common in clinical ophthalmologic practice. Methods: Fifteen ophthalmologists performed one mock clinical examination using conventional equipment and one mock clinical examination using alternative equipment with the potential to reduce exposure to sustained muscular exertions and non-neutral upper arm postures. The alternative equipment included a slit-lamp biomicroscope with inclined viewing oculars, adjustable elbow supports, and a wider table-top with more room for supporting the arms in comparison to the conventional slit-lamp biomicroscope. A wireless binocular indirect ophthalmoscope was also evaluated that had a more even weight distribution than the conventional design. Measurements of upper trapezius and anterior deltoid muscle activity, upper arm posture, and perceived usability were used to compare the conventional and alternative equipment. Results: In comparison to the conventional slit lamp biomicroscope, the alternative slit lamp biomicroscope led to (i) 12% to 13% reductions in upper trapezius muscle activity levels, (ii) a 9% reduction in left anterior deltoid muscle activity levels, and (iii) a 15% reduction in the percentage of work time spent with the left upper arm elevated in positions greater than 60°. In addition, participants rated the comfort and adjustability of both the alternative slit lamp biomicroscope and binocular indirect ophthalmoscope more favorably than the conventional equipment. Conclusions: The results suggest that the alternative slit-lamp biomicroscope may help to reduce overall muscular demands and non-neutral postures of the neck and shoulder region among ophthalmologists.

Outcomes of treatment of fungal keratitis at the University of Iowa Hospitals and Clinics: a 10-year retrospective analysis.

PURPOSE: To evaluate the outcomes of medical and surgical management of fungal keratitis at a tertiary care eye center. METHODS: A retrospective review was performed of the medical records of all patients with a diagnosis of microbiologically or histopathologically confirmed fungal keratitis at the University of Iowa Hospitals and Clinics from July 1, 2001, through June 30, 2011. The main outcome measure was a microbiological cure with either medical therapy alone or medical therapy combined with therapeutic keratoplasty (TKP). The secondary outcome measures were graft survival of the TKPs and subsequent optical keratoplasties (OKPs) and visual outcome. RESULTS: Seventy-three eyes met the inclusion criteria. A microbiological cure was achieved in 72 eyes (98.6%). Forty-one eyes (56.2%) were treated with medical therapy alone, and 32 (43.8%) eyes required 1 TKP (29 eyes) or 2 TKPs (3 eyes). Among the 32 eyes treated with TKP, 17 (53.1%) maintained a clear graft. Among 15 eyes with failed grafts, 12 eyes ultimately achieved clear grafts after a total of 19 OKP procedures. Among 41 eyes treated with medical therapy alone, all 3 eyes treated with OKP remained clear. The final median best-corrected visual acuity was 20/30 in the medical therapy group and 20/40 in the TKP group. CONCLUSIONS: A high microbiological cure rate can be achieved in eyes with fungal keratitis; however, TKP is often needed to achieve this objective. A good final visual outcome can be achieved in most cases, but multiple keratoplasty procedures may be required.

Treatment of aniridia with Boston type I keratoprosthesis.

PURPOSE: To report the outcomes of Boston keratoprosthesis (K-pro) type I implantation for congenital aniridia. METHODS: A retrospective review of the medical records of every patient with congenital aniridia who underwent Boston K-pro type I implantation at the University of Iowa Hospitals and Clinics from January 1, 2009, through December 31, 2011 was performed. The main outcome measures were visual acuity, graft retention, and postoperative complications. RESULTS: A total of 7 eyes (7 patients) met the inclusion criteria. The mean patient age was 52 years (range, 12-85 years). The preoperative visual acuity was 20/1600 in 6 eyes (85.7%) and hand motions in 1 eye (14.3%). After a median follow-up period of 18 months (range, 3-30 months), the median final best spectacle-corrected visual acuity was 20/200 (range, 20/100 to light perception). This included 2 eyes (28.6%) that were 20/100 and 5 eyes (71.4%) that were better than 20/300. Compared with the preoperative best spectacle-corrected visual acuity, the final vision was improved in 6 eyes (85.7%) and worse in 1 eye (14.3%). The K-pro graft was retained in all 7 eyes (100%). The most common complication was the formation of a retroprosthetic membrane in 3 eyes (42.9%), none of which required either a YAG capsulotomy or a vitrectomy. One eye (14.3%) developed a wound dehiscence that required surgical repair. CONCLUSIONS: The Boston K-pro type I is a good option for the visual rehabilitation of eyes with congenital aniridia.

Confirmation of the association between the TCF4 risk allele and Fuchs endothelial corneal dystrophy in patients from the Midwestern United States.

PURPOSE: To determine the role of the single nucleotide polymorphism (SNP) (rs613872) in the TCF4 gene in Fuchs endothelial corneal dystrophy (FECD) in patients from Iowa. METHODS: A cohort of 82 patients with FECD and 163 normal control subjects from Iowa were genotyped at the SNP rs613872 using a real-time allelic discrimination assay. RESULTS: The frequencies of the alleles of rs613872 were compared between FECD patients and control subjects. A highly significant association (p-value = 2.96 × 10(-10)) was detected between this SNP and FECD. Comparison of the genotypes of SNP rs613872 between FECD patients and control subjects produced a p-value of 2.43 × 10(-10). CONCLUSION: Prior reports have shown that SNP rs613872 in the TCF4 gene is highly associated with FECD. Our study confirms this association and shows that the TCF4 gene has an important role in the pathogenesis of corneal disease in patients from Iowa.

Photorefractive keratectomy modification of postkeratoplasty anisometropic refractive errors.

PURPOSE: To evaluate the efficacy, refractive predictability and stability, and complications of photorefractive keratectomy (PRK) with adjunctive mitomycin C (MMC) in patients with postkeratoplasty anisometropia. METHODS: A retrospective review was carried out of all cases of PRK performed for postkeratoplasty anisometropia with the VISX Star S4 excimer laser with MMC between January 1, 2004, and December 31, 2008. The main outcome measures were best spectacle-corrected distance visual acuity (CDVA) and patient tolerance of full spectacle refractive correction. Secondary outcome measures were uncorrected distance visual acuity (UDVA), refractive accuracy and stability, and complications. RESULTS: Twenty cases met the inclusion criteria. At 6 months, the spectacle CDVA had improved from a preoperative mean of 20/50 to 20/30 (P = 0.01). Ten eyes (50%) gained 2 or more lines of CDVA. Eighteen eyes (90%) had a CDVA of 20/40 or better. All 20 patients (100%) were subjectively satisfied with full binocular spectacle correction. There was an improvement in UDVA from a preoperative mean of 20/282 to 20/52 (P < 0.001). Thirteen patients (65%) had an UDVA of 20/40 or better. There was a reduction in the mean refractive spherical equivalent from -5.2 to -0.9 diopters (D), in myopia from -7.6 to -1.8 D, and in astigmatism from 4.9 to 2.0 D. No significant change in visual acuity or refractive error occurred between 3 and 12 months. No sight-threatening complications occurred. One eye (5%) lost 2 lines of CDVA. CONCLUSIONS: PRK with adjunctive MMC is an effective method of reducing postkeratoplasty anisometropia and providing satisfactory spectacle rehabilitation.

Eyelid procedures in patients who have undergone Boston keratoprosthesis surgery.

PURPOSE: Artificial corneas or keratoprostheses such as the Boston keratoprosthesis (KPro) are being used more frequently to provide a clear corneal window in patients with severe corneal disease. A significant percentage of patients who undergo Boston KPro implantation require subsequent eyelid surgery. However, few articles in peer-reviewed literature evaluate the indication and outcome of eyelid procedures after Boston KPro implantation. This study examines the frequency, nature, and outcomes of oculoplastic procedures in patients with Boston KPro implantation. METHODS: A retrospective chart review was conducted of all KPro-1 procedures performed at the University of Illinois at Chicago between December 2006 and September 2010 and all KPro-1 and KPro-2 procedures performed at the University of Iowa between December 2008 and October 2010. RESULTS: One hundred and twenty eyes underwent Boston KPro-1 procedures, and 2 eyes underwent Boston KPro-2 procedures. Twenty-one (17.2%) of the 122 eyes required subsequent eyelid alterations. Chemical burn was the most common preoperative corneal diagnosis (8 of 21; 38.1%). A variety of oculoplastic procedures were performed; the most common procedure was a permanent lateral tarsorrhaphy. Seventeen (81.0%) of 21 KPro eyes that underwent oculoplastic procedures maintained the KPro at an average of 12.4 months of follow up. CONCLUSIONS: A significant number of patients with Boston KPros require subsequent eyelid surgery. With limited existing literature and increasing popularity for using Boston KPros to treat severe corneal disease, it is essential for oculoplastic and corneal surgeons to understand the need for eyelid alterations in these patients and the surgical intricacies surrounding these cases.

Impact of eye bank lamellar tissue cutting for endothelial keratoplasty on bacterial and fungal corneoscleral donor rim cultures after corneal transplantation.

PURPOSE: To determine if the lamellar cut of donor tissue for endothelial keratoplasty (EK) by an eye bank facility is associated with a change in the prevalence of positive bacterial or fungal donor rim cultures after corneal transplantation. METHODS: A retrospective review was conducted of bacterial and fungal cultures of donor rims used for corneal transplantation at a tertiary eye care center from January 1, 2003, to December 31, 2008, with tissue provided by a single eye bank. The cases were divided into 2 groups. Group 1 ("no-cut") included keratoplasty procedures in which a lamellar cut was not performed. Group 2 ("precut") included EK procedures in which a 4-hour period of prewarming of tissue followed by a lamellar cut was performed in the eye bank before tissue delivery to the operating surgeon. RESULTS: There were 351 donor rim cultures in group 1 and 278 in group 2. Bacterial cultures were positive in 30 donor rims (8.5%) in group 1 and 13 (4.7%) in group 2 (P = 0.058). Positive bacterial cultures were not associated with any postoperative infections. Fungal cultures were positive in 8 donor rims (2.3%) in group 1 and 7 (2.5%) in group 2 (P = 1.0). Positive fungal cultures were associated with 2 cases (13.3%) of postoperative fungal infections. CONCLUSIONS: Corneal donor tissue can be precut for EK by trained eye bank personnel without an increased risk of bacterial or fungal contamination.

Glaucoma therapy escalation in eyes with pseudophakic corneal edema after penetrating keratoplasty and Descemet's stripping automated endothelial keratoplasty.

The purpose of this study was to determine and compare the prevalence of glaucoma therapy escalation (GTE) after penetrating keratoplasty (PKP) and Descemet's stripping automated endothelial keratoplasty (DSAEK) in eyes with a surgical indication of pseudophakic corneal edema. A retrospective review was conducted of the medical records of all patients who underwent PKP or DSAEK to treat pseudophakic corneal edema at a tertiary eye care center from January 1 2003 to December 31, 2006. Eyes that were treated with PKP from January 1, 2003 to December 31, 2004 and with DSAEK from January 1, 2005 to December 31, 2006 were included in the statistical analysis. Inclusion criteria included satisfactory preoperative control of intraocular pressure (IOP) and follow-up of at least 12 months. The main outcome measure was GTE, which was defined as a sustained requirement for escalation of topical medical therapy or the need to provide surgical intervention to maintain a satisfactory postoperative IOP. Among 54 eyes that met the inclusion criteria, GTE occurred in 7 (35.0%) of 20 eyes after PKP and in 14 (41.2%) of 34 eyes after DSAEK (P = 0.78) during a mean follow-up period of 27.6 and 28.6 months, respectively. Surgical escalation occurred in 2 (10.0%) eyes after PKP and 2 (5.9%) eyes after DSAEK (P = 0.62), and was associated with late-onset endothelial graft failure in all four eyes. Glaucoma therapy escalation is relatively common and occurs with comparable frequency in eyes with pseudophakic corneal edema after PKP and DSAEK.

Comparison of outcomes of penetrating keratoplasty versus Descemet's stripping automated endothelial keratoplasty for penetrating keratoplasty graft failure due to corneal edema.

To evaluate the outcomes of repeat corneal transplantation, either penetrating keratoplasty (PKP) or Descemet's stripping automated endothelial keratoplasty (DSAEK), for penetrating keratoplasty grafts which failed due to corneal edema. The charts of 24 eyes with failed PKP grafts, due to corneal edema, which underwent a repeat corneal transplant (PKP in 17 eyes [Group 1] and DSAEK in seven eyes [Group 2]) between 2003 and 2007 were retrospectively reviewed. There was no statistically significant difference in the median postoperative visual acuity between the two groups at 1, 2, or 3 years. In Group 1, two (18%) eyes had a final visual acuity ≥ 20/40, in contrast to four (80%) eyes in Group 2, which was statistically significant (P = 0.038). Seven (41%) of the Group 1 eyes developed postoperative complications compared to only one (14%) eye in Group 2. Eleven (65%) of the Group 1 eyes and five (71%) of Group 2 eyes had clear grafts on the last examination. There was no statistically significant difference in the graft survival rate for Group 1 versus Group 2 at 3 years (57.9% vs 68.6%, P = 0.507). There was a trend towards better postoperative visual acuity, a lower postoperative complication rate, and a higher graft survival rate in eyes that underwent DSAEK rather than repeat PKP for graft failure secondary to corneal edema. Given this small, retrospective study, future studies comparing repeat PKP with DSAEK are warranted to determine which procedure allows for improved outcomes.

A survey study of musculoskeletal disorders among eye care physicians compared with family medicine physicians.

PURPOSE: To evaluate the prevalence of musculoskeletal disorders among eye care physicians compared with family medicine physicians. DESIGN: Case control study. PARTICIPANTS AND CONTROLS: Ophthalmologists and optometrists at the University of Iowa and Mayo Clinic (participants) and family medicine physicians at the University of Iowa and Mayo Clinic (controls). METHODS: An electronic survey was e-mailed to all subjects. MAIN OUTCOME MEASURES: The prevalence of musculoskeletal symptoms between eye care providers and family medicine physicians (control group). RESULTS: One hundred eight-six surveys were completed by 94 eye care physicians and 92 family medicine physicians with a response rate of 99% and 80%, respectively. There were no significant differences between the 2 groups with regard to mean age, gender, body mass index, years with current employer, or years in practice. Eye care providers, compared with their family medicine colleagues, reported a higher prevalence of neck (46% vs 21%; P<0.01), hand/wrist pain (17% vs 7%; P = 0.03), and lower back pain (26% vs 9%; P<0.01). A greater proportion of eye care physicians classified their job as a high-strain job (high demand, low control; 31% vs 20%) and a lower proportion classified their job as an active job (high demand, high control; 24% vs 47%; p = 0.01). Several job factors reported by eye care providers to contribute to musculoskeletal symptoms included performing the same task repeatedly, working in awkward/cramped positions, working in the same position for long periods, and bending/twisting the back (all P<0.01). CONCLUSIONS: In this survey, the study group, composed of ophthalmologists and optometrists, had a higher prevalence of neck, hand/wrist, and lower back pain compared with family medicine physicians; repetitive tasks, prolonged or awkward/cramped positions, and bending/twisting were contributory factors. Given the ramifications of these findings, future efforts should concentrate on modifications to the eye care providers' work environment to prevent or alleviate musculoskeletal disorders and their personal and socioeconomic burden.

Treatment of ocular surface squamous cell intraepithelial neoplasia with and without mitomycin C.

PURPOSE: To analyze the outcome of excisional biopsy of ocular surface (conjunctival and corneal) squamous cell intraepithelial (in situ) neoplasia with and without the adjunctive use of intraoperative and postoperative mitomycin C. METHODS: A retrospective case review was conducted on 34 consecutive patients with histopathologically proven ocular surface squamous cell intraepithelial neoplasia who were treated from January 1, 1980, to December 31, 2008, at University of Iowa Hospitals and Clinics. Eyes in which a minimum follow-up period of 3 months was available were included in the statistical analysis. RESULTS: Of 34 eyes, 32 met the inclusion criteria. Adjunctive therapy was provided with mitomycin C in 17 eyes, including 13 that had only postoperative treatment and 4 that had only intraoperative treatment. The adjunctive use of mitomycin C was associated with a significantly reduced prevalence of recurrence (5.9% vs. 66.7%; P = 0.0005). When the surgical margins were positive, the use of adjunctive mitomycin C was associated with a reduced prevalence of tumor recurrence (12.5% vs. 55.6%), but this difference was not statistically significant (P = 0.13). When surgical margins were negative, the adjunctive use of mitomycin C was significantly associated with a reduced prevalence of recurrence (0% vs. 83.3%; P = 0.002). CONCLUSIONS: The adjunctive use of mitomycin C is significantly associated with a reduction in the prevalence of postoperative recurrences of ocular surface squamous cell intraepithelial neoplasia and should be considered as an adjunctive therapy even when surgical margins are negative.

Initial resident refractive surgical experience: outcomes of PRK and LASIK for myopia.

PURPOSE: To evaluate and compare the outcome of initial resident surgical experience with photorefractive keratectomy (PRK) and LASIK. METHODS: Retrospective review of all cases performed with the VISX Star S4 platform (Abbott Medical Optics) between July 1, 2003 and June 30, 2007. Inclusion criteria were spherical equivalent of -0.50 to -10.00 diopters (D), refractive astigmatic error of ≤3.00 D, intention to provide full distance correction, and minimum 3-month postoperative follow-up after initial ablation or retreatment (if performed). RESULTS: A total of 153 cases performed by 20 different residents met the inclusion criteria; 38 eyes underwent PRK and 115 eyes had LASIK. After initial treatment, mean Snellen uncorrected distance visual acuity (UDVA) after PRK was 20/17.3 and after LASIK was 20/19.5. Photorefractive keratectomy was associated with a significantly better approximation between preoperative corrected distance visual acuity (CDVA) and postoperative UDVA (ΔlogMAR 0.009 vs 0.091; P=.004) and a greater percentage of eyes that achieved UDVA of 20/20 or better (94.7% vs 78.3%; P=.02) or 20/30 or better (100% vs 87.8%; P=.02). There was a higher prevalence of retreatment in eyes that underwent LASIK (7.0% vs 0%; P=.20). One (0.9%) eye lost 2 lines of CDVA after LASIK. CONCLUSIONS: Supervised refractive surgery residents can achieve excellent visual outcomes in patients operated during their initial refractive experience. Photorefractive keratectomy was associated with better visual outcome than LASIK.