CLINICAL OUTCOMES AND TREATMENT COURSE OF EYES WITH NEOVASCULAR AGE-RELATED MACULAR DEGENERATION FOLLOWING THE DEVELOPMENT OF ENDOPHTHALMITIS.

PURPOSE: To evaluate the clinical course of patients with neovascular age-related macular degeneration (nAMD) after developing endophthalmitis during their treatment with intravitreal injections. METHODS: Multicenter, retrospective series. RESULTS: From April 2013 to October 2018, 196,598 intravitreal anti-vascular endothelial growth factor (VEGF) injections were performed, with 75 cases of endophthalmitis (incidence 0.0381%). There was no association between intravitreal anti-VEGF drug (P = 0.29), anesthetic method (P = 0.26), povidone concentration (P = 0.22), or any intraprocedure variable and endophthalmitis incidence. Seventy-two patients (96%) were treated with intravitreal tap and inject , while 3 underwent immediate pars plana vitrectomy. After endophthalmitis resolution, 17 patients (22.7%) were not re-treated for nAMD (in 10 cases due to inactive disease; follow-up, 115 ± 8.4 weeks). Patients required less frequent anti-VEGF injections after infection (7.4 ± 0.61 weeks vs. 11.5 ± 1.8 weeks; P = 0.004). Preinfection logarithm of the minimum angle of resolution visual acuity was 0.585 ± 0.053 (∼20/77). It worsened with endophthalmitis (1.67 ± 0.08, ∼20/935; P < 0.001) and again on postendophthalmitis treatment day 1 (1.94 ± 0.064; count fingers; P < 0.001), but improved after reinitiating nAMD therapy (1.02 ± 0.11; ∼20/209; P < 0.001). Better visual acuity on postendophthalmitis week 1 (P = 0.002) and reinitiation of nAMD treatment (P = 0.008) were associated with better final visual acuity, and streptococcal culture with worse visual acuity (P = 0.028). The postendophthalmitis treatment interval was associated with the anti-VEGF drug used (aflibercept = ranibizumab > bevacizumab; P < 0.001). CONCLUSION: Patients with nAMD required fewer injections after endophthalmitis, suggesting a biological change in disease activity. Neovascular age-related macular degeneration became quiescent in 13.3% of eyes. Most achieved better outcomes with anti-VEGF reinitiation.

Scleral buckle removal in the vitrectomy era: a 20-year clinical experience.

PURPOSE: To describe the effect of scleral buckle (SB) removal on preoperative symptoms and signs prompting removal and to assess the risk of recurrent retinal detachment (RD) after SB removal. METHODS: A retrospective study of 36 patients who underwent SB removal between August 1988 and December 2007 was performed. Indications for SB removal, presence or absence of pain or diplopia, and recurrence of RD were recorded. Composite RD rates were estimated from previously published studies and stratified into those occurring during the previtrectomy era versus later (1980 to present). RESULTS: Mean follow-up time was 75.5 months after SB removal. Thirty-two of 33 patients (97%) who had preoperative pain had symptom relief. Twelve of 12 patients who had clinical infection had resolution. Of the four patients with diplopia, two experienced complete resolution and two reported substantial improvement but required prisms to obtain single vision. Four of 34 patients (12%) whose retinas were attached at the time of SB removal developed recurrent RD but were successfully repaired without significant visual loss from the RD. CONCLUSION: Scleral buckle removal is effective in eliminating SB-related pain and infection. Symptomatic diplopia can sometimes improve after SB removal. The rates of RD after SB removal observed in this study (12%) and in others performed in the era of vitrectomy were notably lower than those of previous reports.

Intraocular lens power selection in the second eye of patients undergoing bilateral, sequential cataract extraction.

PURPOSE: To determine if the 1-month postoperative error of predicted refraction of the first eye can be used to alter intraocular lens (IOL) power selection and improve refractive results for the second eye in patients undergoing bilateral, sequential phacoemulsification with IOL implantation (phaco/IOL). DESIGN: Retrospective, consecutive, case series. PARTICIPANTS: Three hundred consecutive patients who underwent uncomplicated bilateral, sequential phaco/IOL between January 1, 2006, and December 31, 2007, by a single surgeon using a single IOL platform. METHODS: The observed second eye 1-month postoperative spherical equivalent refractive error was compared with calculations of the hypothetic 1-month postoperative spherical equivalent refractive error if the first eye error had been fully or partially incorporated into the choice of IOL power for the second eye. The optimal amount of partial adjustment was determined. MAIN OUTCOME MEASURES: The error of predicted refraction: the difference between the actual or hypothetic spherical equivalent refractive errors and those predicted by preoperative calculations. RESULTS: A total of 206 patients met inclusion criteria. The average of the absolute value of the unadjusted second eye error (|E(UNADJ)|) was +0.44 diopters (D) compared with +0.42 D for the fully adjusted second eye error (|E(FULL)|). The optimal amount of adjustment of the second eye IOL power was determined to be 50%; the average of the absolute value of this partially adjusted second eye error (|E(PARTIAL,50%)|) was +0.36 D; this was statistically different from |E(UNADJ)| (P<0.0001) and |E(FULL)| (P = 0.001). The statistically significant benefit was observed for patients with either myopic or hyperopic errors in the first eye. The percentages of patients achieving postoperative refractions within 0.5 D and 1.0 D of the predicted refraction were 66.5% and 90.3%, respectively, for the unadjusted second eye, 67.0% and 90.8%, respectively, for the hypothetic fully adjusted second eye, and 74.3% and 93.7%, respectively, for the hypothetic partially adjusted (50%) second eye. CONCLUSIONS: Accounting for 50% of the observed error of predicted refraction of the first eye reduced the error of predicted refraction in the second eye. This novel methodology has the potential to improve the refractive outcomes in the second eye of patients with cataract. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Microbiological spectrum of organisms isolated from explanted scleral buckles.

Scleral buckle removal is an uncommon procedure performed for various reasons. Microbiological information on explanted scleral buckles remains limited. The authors identified 37 cases of scleral buckle removal during an 18-year period. Bacterial cultures isolated an organism in 4 of 9 patients (44%) with clinical infection. Organisms identified included methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Mycobacterium abscessus, and coagulase-negative Staphylococcus species. Bacterial cultures isolated an organism in 3 of 11 patients (27%) without clinical infection. Organisms identified included Nocardia species, Alcaligenes xylosoxidans, and Mycobacterium chelonae. Scleral buckles appearing clinically infected may be associated with more virulent organisms and a greater chance of identifying an organism. Bacterial cultures may be of value for scleral buckles upon removal.

Physician assessment of changing lesion size of predominantly classic choroidal neovascular membranes in age-related macular degeneration.

BACKGROUND AND OBJECTIVE: To quantify the interpretation of fluorescein angiograms of evolving predominantly classic choroidal neovascularization in age-related macular degeneration. PATIENTS AND METHODS: Thirty-six fluorescein angiograms of predominantly classic choroidal neovascularization were used to define 22 fluorescein angiogram pairs. Imaging software was used to measure surface area and greatest linear dimension (GLD). Six retina physicians estimated the change in surface area and GLD for each pair before and after demarcation of the lesions' borders and GLD. RESULTS: For enlarging lesions, the smallest changes consistently detected by physicians were a 5% to 15% increase in surface area and a 5% to 15% increase in GLD; for shrinking lesions, they were a 5% to 15% decrease in surface area and a 5% to 15% decrease in GLD. Linear regression demonstrated moderate correlation between physician and software estimates of surface area and GLD change (r(2) = 0.50 and 0.67, respectively; P < .001), which was higher with lesion demarcation (r(2) = 0.91 and 0.93, respectively; P < .001). CONCLUSION: Computer-assisted demarcation of lesion surface area and GLD reduced variability in physicians' estimates of choroidal neovascularization size change and improved correlation with software measurements.

Risk factors for scleral buckle removal: a matched, case-control study.

PURPOSE: To identify preoperative, perioperative, and postoperative risk factors for scleral buckle (SB) removal. DESIGN: Retrospective, consecutive, matched, case-control study. METHODS: Cases included all patients undergoing SB removal between August 1988 and December 2007 at a single academic center. Cases were matched against four randomly selected control patients who underwent SB implantation during the same year as the case. Odds ratios (OR) were calculated for each factor investigated. RESULTS: Forty cases of SB removal and 148 matched control cases were identified. Three cases of SB removal were omitted from analysis because of incomplete records. Factors associated with SB removal for any reason, using univariate analysis, included concurrent globe-penetrating injury at time of SB placement (OR, 24; 95% confidence interval [CI], 2.9 to 200), concurrent pars plana vitrectomy (PPV) (OR, 17.3; 95% CI, 4.9 to 61), diabetes mellitus (DM) (OR, 7.3; 95% CI, 1.8 to 30), prior chronic topical ocular therapy (OR, 4.3; 95% CI, 1.7 to 11), and subsequent ocular procedures (OR, 3.4; 95% CI, 1.5 to 7.5). Factors independently associated with SB removal using multivariate analysis included concurrent globe-penetrating injury (OR, 27.3; 95% CI, 1.7 to 426), concurrent PPV (OR, 11.3; 95% CI, 2.9 to 45), DM (OR, 8.9; 95% CI, 1.3 to 58), and subsequent ocular procedures (OR, 3.9; 95% CI, 1.4 to 11). Factors that did not alter SB removal risk included patient age; gender; and type, size, or location of buckling elements used. CONCLUSIONS: Awareness of these risk factors may be valuable for the surgical planning of retinal detachment repair in patients at higher risk for subsequent SB removal and for risk stratification subsequent to SB implantation.

Natural Background and Anthropogenic Arsenic Enrichment in Florida Soils, Surface Water, and Groundwater: A Review with a Discussion on Public Health Risk.

Florida geologic units and soils contain a wide range in concentrations of naturally-occurring arsenic. The average range of bulk rock concentrations is 1 to 13.1 mg/kg with concentrations in accessary minerals being over 1000 mg/kg. Florida soils contain natural arsenic concentrations which can exceed 10 mg/kg in some circumstances, with organic-rich soils often having the highest concentrations. Anthropogenic sources of arsenic have added about 610,000 metric tons of arsenic into the Florida environment since 1970, thereby increasing background concentrations in soils. The anthropogenic sources of arsenic in soils include: pesticides (used in Florida beginning in the 1890's), fertilizers, chromated copper arsenate (CCA)-treated wood, soil amendments, cattle-dipping vats, chicken litter, sludges from water treatment plants, and others. The default Soil Cleanup Target Level (SCTL) in Florida for arsenic in residential soils is 2.1 mg/kg which is below some naturally-occurring background concentrations in soils and anthropogenic concentrations in agricultural soils. A review of risk considerations shows that adverse health impacts associated with exposure to arsenic is dependent on many factors and that the Florida cleanup levels are very conservative. Exposure to arsenic in soils at concentrations that exceed the Florida default cleanup level set specifically for residential environments does not necessarily pose a meaningful a priori public health risk, given important considerations such as the form of arsenic present, the route(s) of exposure, and the actual circumstances of exposure (e.g., frequency, duration, and magnitude).

Early results of small-incision Descemet's stripping and automated endothelial keratoplasty.

PURPOSE: To describe our technique and early results of Descemet's stripping and automated endothelial keratoplasty (DSAEK), identify perioperative complications, and discuss their management. DESIGN: Prospective, noncomparative, surgical case series. PARTICIPANTS: Twenty-six eyes of 26 patients who had corneal edema from Fuchs' endothelial dystrophy, pseudophakic bullous keratopathy, or aphakic bullous keratopathy. INTERVENTION: The donor corneal lenticule was prepared using a microkeratome and an artificial anterior chamber maintainer. Stripping of the diseased host endothelium was performed under viscoelastic using a 2.75-mm clear corneal temporal incision. The incision was enlarged to approximately 4.2 mm to allow placement of a folded 8.5-mm-diameter donor corneal lenticule. The donor graft was positioned using a temporary air bubble that was partially evacuated after 7 minutes. The corneal wound was closed with a single 10-0 nylon suture. MAIN OUTCOME MEASURES: Preoperative and postoperative best spectacle-corrected visual acuity (BSCVA), manifest refraction, keratometry, topographic astigmatism, corneal pachymetry, and perioperative complications. RESULTS: Three months postoperatively, all donor grafts remained clear. The average 3-month postoperative BSCVA was 20/45 (range, 20/20-20/150). The average change in refractive astigmatism was 0.12+/-1.15 diopters (D) (range, -1.50 to 3.25). In patients who underwent simple DSAEK (i.e., no intraocular lens implantation), the average postoperative shift in spherical equivalent refractive error was 1.15+/-1.35 D (range, -0.25 to +4.25). Nine of 26 initial grafts dislocated postoperatively and had to be repositioned. Three of the repositioned grafts dislocated again and were replaced with new donor corneal lenticules, all of which remained clear. CONCLUSIONS: Descemet's stripping and automated endothelial keratoplasty uses a mechanical microkeratome to harvest the donor corneal lenticule and mechanical stripping of the diseased host endothelium and Descemet's membrane. Despite a smooth graft-host interface, only 2 patients in the series achieved > or =20/25 vision. The average visual results were comparable to vision after deep lamellar endothelial keratoplasty. Although patients experienced excellent postoperative acuity with minimally induced surgical astigmatism, nearly one third of the donor lenticules needed to be either repositioned or replaced. Nevertheless, DSAEK offers significant advantages over standard penetrating keratoplasty for patients with Fuchs' dystrophy in pseudophakic bullous keratopathy.

New triple procedure: Descemet's stripping and automated endothelial keratoplasty combined with phacoemulsification and intraocular lens implantation.

PURPOSE: To evaluate visual acuity (VA), graft clarity, and refractive outcome of Descemet's stripping and automated endothelial keratoplasty (DSAEK) combined with phacoemulsification and intraocular lens (IOL) implantation in patients with coexisting Fuchs' endothelial dystrophy and immature senile cataracts. DESIGN: Pilot, prospective, noncomparative, surgical case series. PARTICIPANTS: Twenty-one eyes of 21 consecutive patients with coexisting visually significant immature senile cataracts and Fuchs' corneal dystrophy with guttata of Descemet's membrane and either microcystic epithelial edema or stromal edema presenting to a single academic eye institute. METHODS: All patients underwent phacoemulsification and posterior chamber IOL implantation through temporal clear corneal incision, followed by DSAEK. The intent was to render all eyes as close to emmetropia as possible. MAIN OUTCOME MEASURES: Six-month postoperative best spectacle-corrected VA (BSCVA), refractive spherical equivalent (SE), refractive astigmatism, and keratometry. RESULTS: Average BSCVAs were 20/68 preoperatively and 20/34 postoperatively (P<0.0001). The postoperative SE refractive error was +0.45 diopters (D), on average +1.13 D more hyperopic than predicted by preoperative lens power calculations. Overall, 13 patients (62%) were within 1.00 D and 21 (100%) were within 2.00 D of emmetropia postoperatively. Preoperative and postoperative average refractive astigmatisms were 1.46 D and 1.56 D, respectively (P = 0.69). Complications included graft dislocations requiring repositioning (3), 2 of which experienced recurrent dislocation requiring reoperation with a new graft; acute graft rejection (3); and pupillary block glaucoma (2). CONCLUSIONS: This pilot case series of 6-month results of DSAEK combined with phacoemulsification and IOL implantation suggests that it provides rapid visual rehabilitation with predictable refractive outcomes.

Simple technique to unfold the donor corneal lenticule during Descemet's stripping and automated endothelial keratoplasty.

We describe a technique to facilitate unfolding and prevent inversion of the donor corneal lenticule during Descemet's stripping and automated endothelial keratoplasty (DSAEK). The donor corneal lenticule is unfolded in the anterior chamber using a bent 30-gauge needle on a 3 cc air syringe. The needle tip is used to pinion the edge of the lenticule while an air bubble is simultaneously injected between the folded edges of the donor graft. A gentian-violet dye mark placed on the peripheral stromal surface of the donor lenticule is used to confirm proper graft orientation. The simple technique of simultaneously fixating the donor lenticule while injecting air ensures that the graft unfolds correctly and minimizes potential mechanical trauma to the endothelium.

Use of an air-fluid exchange system to promote graft adhesion during Descemet's stripping automated endothelial keratoplasty.

Dislocation of the graft is a well-recognized complication of Descemet's stripping automated endothelial keratoplasty (DSAEK). We describe a technique to promote adhesion of the graft during DSAEK using an anterior chamber air-fluid infusion and exchange for direct control of the pressure and medium used to tamponade the graft against the host stroma.

Accuracy of surrogate decision making in elective surgery.

PURPOSE: To assess the accuracy of surrogate decision making for elective cataract surgery. SETTING: Comprehensive Ophthalmology Department of Tertiary Care Hospital. METHODS: Decisions regarding elective cataract surgery of currently competent, elderly patients were compared with the predictions of patient-identified surrogate decision makers in scenarios of current state of mental health and progressive dementia. Patients were identified (age >50 years, Mini-Mental Status Score >20, absence of significant noncataract pathology) consecutively at a scheduled clinic visit to a single provider. Preferences for cataract surgery in the current state of health and hypothetical progressive dementia were assessed on a Likert scale. The same interviewer contacted patient-identified surrogate decision makers within 48 hours. Independently, a survey of community ophthalmologists was performed. The concordance of surrogate predictions with patient preferences (32 pairs) was assessed using percentage agreement, the kappa coefficient with dichotomous Likert scale data, and chi-square analyses (concordance beyond chance). RESULTS: In their current state of health, most patients said they would prefer to have surgery if they were deemed to have a visually significant cataract, which was accurately predicted by surrogates (72% agreement, kappa = 0.65, chi square = 16.5). In a hypothetical dementia scenario, contrary to perceptions of patients and their surrogates, proxies were unable to accurately represent a patient's wishes for elective cataract surgery (34% agreement, kappa = 0.23, chi square = 14.4). Physicians tended to withhold intervention in the dementia scenario. CONCLUSIONS: The findings suggest that current methods of decision making in elective surgery for patients unable to make autonomous decisions may be seriously flawed. This extends previous findings of inaccuracy with the substituted judgment approach to end-of-life issues to reflect elective surgical scenarios.

Descemet stripping and automated endothelial keratoplasty (DSAEK) in eyes with failed penetrating keratoplasty.

PURPOSE: To report our results of using Descemet stripping and automated endothelial keratoplasty (DSAEK) in eyes with failed penetrating keratoplasty (PK). METHODS: An institutional review board-approved, prospective, surgical case series of 7 eyes of 7 consecutive patients undergoing DSAEK for graft failure after 1 or more PKs at 1 academic eye center. RESULTS: The mean follow-up period was 13.3 months (range, 9-18 months). One eye suffered recurrent donor graft dislocation and elected to undergo repeat PK instead of repeat DSAEK. Of the remaining 6 patients, the average preoperative visual acuity (VA) was 20/851 compared with a best-corrected visual acuity (BCVA) of 20/65 postoperatively (P = 0.008). After DSAEK, 6 (100%) eyes showed improved BCVA, and 4 of 6 eyes (67%) achieved a BCVA of 20/40 or better. All 6 grafts remained clear at the last follow-up visit. Two eyes showed graft dislocation on the first postoperative day and underwent repositioning of the lenticule with good results. Two other eyes were diagnosed with primary iatrogenic graft failure within 1 week of DSAEK and underwent repeat DSAEK with new donor tissue with good results. One eye experienced acute graft rejection that was successfully treated with topical steroids. CONCLUSIONS: This pilot series of DSAEK in eyes with graft failure from previous PK shows favorable VA and graft clarity outcomes. The complications observed were similar to those observed for DSAEK for Fuchs dystrophy and pseudophakic bullous keratopathy and include graft dislocation, iatrogenic graft failure, and homograft rejection.

Visual acuity, refractive error, and endothelial cell density six months after Descemet stripping and automated endothelial keratoplasty (DSAEK).

PURPOSE: To evaluate visual acuity, refractive outcomes, and endothelial cell density 6 months after Descemet stripping and automated endothelial keratoplasty (DSAEK). METHODS: We performed an institutional review board-approved prospective study of a surgical case series of 34 patients at 2 institutions undergoing DSAEK for Fuchs endothelial dystrophy, pseudophakic bullous keratopathy, or aphakic bullous keratopathy with or without simultaneous phacoemulsification and intraocular lens implantation. Clinical outcomes, including best spectacle-corrected visual acuity (BSCVA), spherical equivalent refraction, and refractive astigmatism and topographic or keratometric astigmatism, were assessed at the 6-month postoperative examination and compared with preoperative values with paired Student t tests. The change in endothelial cell density from the eye bank examination to 6 months after transplantation was similarly evaluated. RESULTS: BSCVA averaged 20/99 preoperatively and 20/42 postoperatively (P < 0.0001). After DSAEK, 30 (88.2%) of 34 patients showed improved BSCVA, and 21 (61.8%) of the 34 patients achieved a BSCVA of 20/40 or better. For patients not undergoing simultaneous phacoemulsification and intraocular lens implantation, a hyperopic shift in refraction of 1.19 +/- 1.32 D was noted. Refractive astigmatism, topographic astigmatism, and keratometry showed no statistically significant change. Endothelial cell density of donor corneas averaged 2826 +/- 370 cells/mm, whereas the mean postoperative density was 1396 +/- 440 cells/mm. This finding corresponded to an average loss of 1426 cells/mm (50% loss; P = 0.0001). The first half of cases experienced an average cell loss of 1674 cells/mm (59% loss) compared with 1181 (41% loss) in the second half of cases (P = 0.005). Three (9%) of 34 grafts experienced iatrogenic graft failure and required reoperation with new donor tissue. Also, 9 (27%) of 34 grafts experienced dislocation in the early postoperative period and required repositioning. CONCLUSIONS: In this prospective study of DSAEK for bullous keratopathy and Fuchs endothelial corneal dystrophy, improvement of visual acuity was achieved with only a mild tendency toward hyperopic shift and without significant induced astigmatism. Endothelial cell loss was significant, however, and may be related to surgical experience.

Quantitative assessment of the 103-hexagon multifocal electroretinogram in detection of hydroxychloroquine retinal toxicity.

PURPOSE: To evaluate the utility of ring ratios in detecting hydroxychloroquine (HCQ) related retinal toxicity using the 103-hexagon multifocal electroretinogram (mfERG). DESIGN: Retrospective cross-sectional study. METHODS: 23 patients taking HCQ were consecutively evaluated for retinal toxicity and divided into those without (HCQ-non-toxic group) and with documented visual field loss (HCQ-toxic group). A control patient group without retinal disease and not on HCQ was used for comparison. 103-hexagon P(1) mfERG amplitude response densities were analysed by averaging the 103 responses into six (age-corrected) concentric rings (R(1)-R(6)), calculating standard ring ratios (R(1):R(2)-R(1):R(6)) and R(5) ring ratios (R(5):R(1)-R(5):R(6)). Receiver operating characteristic curves were used to compare these tests for detecting toxicity. RESULTS: Relative to HCQ-non-toxic and control groups, the HCQ-toxic group showed generalised reduction of the 103-hexagon mfERG absolute responses most prominent in the foveal/pericentral regions. R(5) ring ratios were superior to standard ring ratios in discriminating the HCQ-toxic from the HCQ-non-toxic and control groups and were approximately equivalent to pericentral absolute ring responses in detecting HCQ retinal toxicity by receiver operating characteristic criteria, with R(5):R(4) and R(5):R(3) ratios performing best. However, R(5) ring ratios revealed improved sensitivity over absolute ring responses (89% vs 73%) at a 95% specificity threshold. CONCLUSIONS: Ring ratio analysis using the R(5) ring response as the 'internal reference ring' appeared equivalent to pericentral absolute ring responses in detecting HCQ retinal toxicity, and possibly superior at clinically desirable specificity thresholds. R(5) ring ratios did not require age correction, a potential clinical advantage over absolute ring responses.

Intraoperative retinal tear formation and postoperative rhegmatogenous retinal detachment in transconjunctival cannulated vitrectomy systems compared with the standard 20-gauge system.

OBJECTIVE: To compare 20-gauge standard pars plana vitrectomy (PPV) with transconjunctival cannulated PPV in the development of intraoperative retinal breaks and postoperative rhegmatogenous retinal detachments (RRDs) in a large series of patients undergoing PPV for macular pucker or macular hole. METHODS: This study was conducted at an academic tertiary care vitreoretinal practice in Milwaukee, Wisconsin. Patients undergoing 3-port PPV with standard 20-gauge instrumentation were compared with patients undergoing 3-port PPV with transconjunctival cannulated systems, including 20 gauge, 23 gauge, and 25 gauge, from January 1, 2003, through December 31, 2009. The main outcome measures were rates of intraoperative retinal breaks and postoperative RRD. RESULTS: Four hundred twenty-six unique eyes met inclusion criteria. Fifty-four of 426 eyes (12.7%) were diagnosed as having new retinal tears intraoperatively as follows: 47 of 204 patients (23.0%) undergoing the standard 20-gauge procedure developed intraoperative retinal tears compared with 7 of 211 patients (3.3%) undergoing the transconjunctival cannulated procedure (risk ratio [RR], 0.12; 95% CI, 0.05-0.26; P < .001). Patients experiencing intraoperative retinal tears were not at increased risk of developing postoperative RRD (RR, 1.4; 95% CI, 0.39-5.0; P = .61). Although a trend was present, transconjunctival cannulated vitrectomy was not significantly protective against the development of postoperative RRD (RR, 0.60; 95% CI, 0.17-1.3; P = .14). CONCLUSION: Transconjunctival cannulated PPV, including 20-gauge, 23-gauge, and 25-gauge systems, is associated with significantly reduced rates of intraoperative retinal tear formation compared with standard 20-gauge PPV.

Corneal sensation after descemet stripping and automated endothelial keratoplasty.

PURPOSE: To measure corneal sensation after Descemet stripping and automated endothelial keratoplasty (DSAEK). METHODS: Prospective comparative case series involving 52 eyes of 29 patients in the early postoperative period (<6 months) after small-incision DSAEK. Patients' contralateral eye served as a control. The sample size calculation was calculated assuming an alpha error of 0.05 and a beta error of 0.2. This determined that a sample size of 11 patients would be sufficient to detect a difference in corneal sensation of 5 mm as measured with the Cochet-Bonnet esthesiometer. The nylon filament was used to measure threshold sensation at 9 points on the operative eye and 5 points on the control. The data were analyzed using the paired samples test. RESULTS: Although the results demonstrated mild hypesthesia of the corneal epithelium overlying the donor lenticule, we found no statistically significant difference in corneal sensation at the central point when comparing the DSAEK cornea with the control (57 vs 59 mm, P = 0.13.) In addition, when comparing corresponding points on the epithelium overlying the DSAEK graft and host cornea, no significant difference was found (57 vs 58 mm, P = 0.32). A difference was detected when comparing the average corneal sensation of the DSAEK eye with the control, but careful analysis of the data shows that this was driven by the slight decrease in sensitivity at the temporal incisional point (57 vs 59 mm, P = 0.002). CONCLUSIONS: The results of this prospective study demonstrate the relative preservation of corneal sensitivity after DSAEK. Preservation of corneal sensation may provide another advantage of DSAEK over traditional penetrating keratoplasty.

The use of best visual acuity over several encounters as an outcome variable: an analysis of systematic bias.

PURPOSE: To investigate whether the use of the best of multiple measures of visual acuity as an endpoint introduces bias into study results. METHODS: Mathematical models and Monte Carlo simulations were used. A model was designed in which a hypothetical intervention did not influence the visual acuity. The best of one or more postintervention measures was used as the outcome variable and was compared to the baseline measure. Random test-retest variability was included in the model. RESULTS: When the better of two postintervention measures was used as the outcome variable with a sample size of 25, the model falsely rejected the null hypothesis 55% of the time. When the best of three measures was used, the false-positive rate increased to 90%. The probability of falsely rejecting the null hypothesis increased with increasing sample size, also increasing the number of measures used to select the outcome variable. CONCLUSIONS: Using the best of multiple measures as an outcome variable introduces a systematic bias resulting in false conclusions of improvement in that variable. The use of best of multiple measures of visual acuity as an outcome variable should be avoided.

Well-tolerated intracorneal wood foreign body of 40-year duration.

PURPOSE: To report the diagnosis and management of a patient with a well-tolerated, long-standing retained intracorneal foreign body. METHODS: We describe the case of a 62-year-old man with a 40-year-old retained wood foreign body within the posterior stroma of the cornea. To the authors' knowledge, this is the longest standing intracorneal foreign body reported in the literature. RESULTS: The foreign body was asymptomatic, well tolerated, and appeared encapsulated, so the patient was carefully observed. One year later, the examination remained stable. CONCLUSIONS: Our case seems to violate the classic teaching that some inorganic intracorneal foreign bodies are well tolerated, whereas organic foreign bodies are poorly tolerated. It is possible that foreign organic material--if early infection is avoided--can be well tolerated by the eye.