The frequency of snowline-region planets from four-years of OGLE-MOA-Wise second-generation microlensing.

We present a statistical analysis of the first four seasons from a "second-generation" microlensing survey for extrasolar planets, consisting of near-continuous time coverage of 8 deg2 of the Galactic bulge by the OGLE, MOA, and Wise microlensing surveys. During this period, 224 microlensing events were observed by all three groups. Over 12% of the events showed a deviation from single-lens microlensing, and for ~1/3 of those the anomaly is likely caused by a planetary companion. For each of the 224 events we have performed numerical ray-tracing simulations to calculate the detection efficiency of possible companions as a function of companion-to-host mass ratio and separation. Accounting for the detection efficiency, we find that 55 - 22 + 34 % of microlensed stars host a snowline planet. Moreover, we find that Neptunes-mass planets are ~ 10 times more common than Jupiter-mass planets. The companion-to-host mass ratio distribution shows a deficit at q ~ 10-2, separating the distribution into two companion populations, analogous to the stellar-companion and planet populations, seen in radial-velocity surveys around solar-like stars. Our survey, however, which probes mainly lower-mass stars, suggests a minimum in the distribution in the super-Jupiter mass range, and a relatively high occurrence of brown-dwarf companions.

Corneal endothelial safety following subconjunctival and intrastromal injection of bevacizumab for corneal neovascularization.

The purpose of this study is to determine the effect on endothelial cell density and morphology of combined subconjunctival and intracorneal injection of bevacizumab for the treatment of corneal neovascularization (NV). The charts and specular microscopy images of ten consecutive patients with corneal NV, who received combined subconjunctival+intracorneal injections of bevacizumab were reviewed. Patients received three injections of bevacizumab 25 mg/mL (1.25 mg/0.05 mL subconjunctival and 1.25 mg/0.05 mL intrastromal) 4-6 weeks apart. Endothelial cell counts (ECCs) and morphological changes were assessed by non-contact specular microscopy performed at baseline, 1 month after each injection and at 3 and 6 months after the last injection. There were no significant changes in ECCs (p = 0.663), coefficient of variation (p = 0.076), percentage of hexagonal cells (p = 0.931) or mean corneal thickness (p = 0.462) from pre-injection values to the 6-month follow-up values. There were no intraoperative or postoperative complications. In our series, the use of combined subconjunctival and intracorneal bevacizumab did not cause any decrease in ECCs or morphological alterations up to 6 months after the last of three injections. Further studies are required to confirm long-term safety in a larger sample population with longer follow-up, as well as the ideal dose, route of administration and frequency of bevacizumab administration.

Superior versus inferior conjunctival autografts combined with fibrin glue in the management of primary pterygia.

PURPOSE: To compare the outcomes of superior versus inferior conjunctival autograft (CAU) in the prevention of recurrence after performing a pterygium surgery in patients with primary pterygia. METHODS: This was a prospective randomized study of 60 eyes of 60 patients with primary pterygium. All the eyes underwent pterygium excision and were assigned randomly to receive either superior (30 eyes) or inferior (30 eyes) CAU. All grafts were attached with fibrin glue. The patients were followed up on postoperative day 1, day 7, 1 month, 3 months, and 6 months. RESULTS: Outcome measures included rate of recurrence, mean surgical time, visual analog scale pain score, and amount of pain medication required in the first postoperative week. The mean surgical time, visual analog scale pain score, and amount of pain medication required in both groups were not statistically different. A follow-up of at least 6 months (mean 5.5 ± 1.1 months) was achieved in 49 eyes of 49 patients (24 eyes in the superior CAU group and 25 eyes in the inferior CAU group). One eye in the superior CAU group (4.2%) and 1 eye in the inferior CAU group (4.0%) developed pterygium recurrence. There was no statistically significant difference in the recurrence rates between the 2 groups. In the inferior CAU group, mild localized donor site scarring was noted in 2 patients (8.3%). CONCLUSIONS: Pterygium excision with superior or inferior CAU secured with fibrin glue is safe and effective. There was no significant difference in surgical time, pain, and recurrence rates of pterygium after excision with superior or inferior CAU.

Secondary intraocular lens interventions: predisposing factors, indications and coincident procedures.

To evaluate the predisposing factors, indications and coincident procedures in patients requiring a secondary intraocular lens (IOL)-related intervention. We reviewed data on 183 consecutive secondary IOL-related procedures. Information collected included demographics, predisposing factors, IOL status, indication for surgery, coincident procedures, and final IOL location and fixation method. Of the 183 procedures performed, 73 were secondary IOL implantations, 68 were IOL exchanges and 42 were IOL repositionings. Predisposing factors were found in 88.6 % of the cases, the most common being complicated cataract surgery (39.8 %) followed by trauma (20.2 %). The most common indications for surgery in the anterior chamber IOL and posterior chamber IOL groups were pseudophakic bullous keratopathy ± failed graft (77.2 %) and subluxated IOL (57.53 %), respectively. A malpositioned or subluxated lens was found in 47.86 % of all pseudophakic eyes. A simultaneous procedure was performed in 67 % of cases, anterior vitrectomy being the most common (43.7 %), followed by keratoplasty (35 %). Secondary IOL-related interventions were associated with predisposing factors, complicated cataract surgery being the most common. Patients implanted with anterior chamber IOLs seemed to have a more complicated course requiring more complex secondary surgeries and associated procedures.

Hypothalamic-pituitary-adrenal axis function following intravitreal triamcinolone acetonide injection.

To evaluate the pituitary-adrenal axis function by means of the adrenocorticotropic hormone (ACTH) stimulation test following a single intravitreal injection of triamcinolone acetonide (IVTA). Prospective comparative clinical interventional study. Twenty-eight patients (28 eyes) received a single IVTA (4 mg in 0.1 ml) for macular edema. The basal cortisol level and the response to 1 µg adrenocorticotropic hormone stimulation were determined on the morning before IVTA injection and at 1 day and 1, 2, and 4 weeks after IVTA injection. Results were compared with those obtained from a control group of 50 healthy subjects. All patients in the study had normal basal cortisol and normal response to ACTH challenge before receiving IVTA. 1 day following IVTA, basal cortisol was suppressed in one patient in the study group. Fasting serum cortisol levels at 1, 2, and 4 weeks after IVTA injection were normal in all patients in the study group. 1 day following IVTA, the peak response to ACTH at 30 min was blunted in four patients (14.3 % of the study group, p = 0.05) and the cortisol response at 60 min was suppressed (p = 0.009). 1 week following IVTA, the response to ACTH challenge was blunted in only one patient. A single IVTA injection may be associated with impaired hypothalamic-pituitary-adrenal function in some patients during the first 24 h following IVTA.

Retrospective contralateral study comparing deep anterior lamellar keratoplasty with penetrating keratoplasty: a patient's perspective.

OBJECTIVE: To compare the visual outcomes and the perspective of patients after deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PKP) in the contralateral eyes of a cohort of patients. DESIGN: Retrospective comparative case series. PARTICIPANTS: Ten patients (20 eyes) who underwent DALK in 1 eye and PKP in the fellow eye. METHODS: In this fellow eye, comparative retrospective case series, visual outcomes were compared in 10 patients (20 eyes) who underwent DALK in 1 eye and PKP in their fellow eye between 1995 and 2009. Visual and refractive outcomes including higher-order aberrations were assessed. Patient satisfaction for both procedures was evaluated using a subjective questionnaire. RESULTS: There was no significant difference in visual or refractive outcomes between the procedures. However, 8 of 10 patients (80%) preferred the PKP eye for vision and overall satisfaction (p = 0.02). Mean follow-up time for the PKP group was 8.4 ± 4.5 years (median, 8.5 years; range, 3-17 years), whereas the mean follow-up time for the DALK group was 2.5 ± 1.6 years (median, 2 years; range, 1-6 years) (p = 0.01). The intra- and postoperative complication rates were low and comparable between both procedures. CONCLUSIONS: More patients prefer the PKP-operated eye when compared with the DALK-operated eye, although there were no significant differences in visual and refractive outcomes between the 2 procedures.

Stromal lamellar dissection of the donor disc: a technique to reduce complications secondary to eccentric trephination during descemet stripping automated endothelial keratoplasty.

PURPOSE: To describe a surgical technique to decrease the incidence and potential complications of an eccentric trephination and improve graft adherence during Descemet stripping automated endothelial keratoplasty. METHODS: Technique description. RESULTS: After resection of the anterior lamella with the microkeratome, the corneoscleral rim in the artificial anterior chamber (AC) is brought under view of the operating microscope and the deep dissection plane of the microkeratome is extended 360 degrees as far peripherally as permitted by the Moria artificial anterior chamber using a crescent blade and 0.12-mm Colibri forceps. The central stroma is marked with gentian violet, and the donor button is released from the AC and then carefully placed and centered on the punching block endothelial side up using the gentian violet mark as a guide and trephined to the desired diameter. The donor graft may then be inserted by the surgeon's preferred technique. CONCLUSIONS: This simple technique allows the surgeon to consistently increase the lamellar dissection diameter while reducing the peripheral graft thickness, which becomes particularly important when the trephination is eccentric. This technique may lead to improved donor adherence and a decrease in the incidence of donor lenticule configuration -related complications.

The era of lamellar keratoplasty, evolving surgical techniques in corneal transplantation: the University of Toronto experience.

OBJECTIVE: To analyze the changing trends in corneal transplantation techniques and the way selective lamellar transplantation has influenced our practice. DESIGN: Retrospective survey of all corneal transplants performed by a single practice at Toronto Western Hospital. PARTICIPANTS: All corneal transplants performed by our office since 2002, the year we performed our first lamellar transplant. METHODS: We retrospectively reviewed all keratoplasty procedures performed in our office between January 2002 and December 2010. Procedures were classified as penetrating keratoplasty (PKP); deep lamellar endothelial keratoplasty (DLEK); Descemet's stripping automated endothelial keratoplasty (DSAEK); or deep anterior lamellar keratoplasty (DALK). RESULTS: A total of 1104 procedures were performed in this period (average, 122.6 per year). Of these, 654 were PKPs (59.3%); 107 DLEKs (9.7%); 219 DSAEKs (19.8%); and 124 DALKs (11.2%). The number of PKPs performed decreased by 61.8% over this 9-year survey. For the last 4 years of the study, the proportions of PKP, DSAEK, and DALK procedures performed were 41%, 40%, and 19%, respectively. CONCLUSIONS: This 9-year audit showed that in less than a decade since its introduction at our institution, selective lamellar transplantation has become the procedure of choice for corneal keratoplasty, accounting for 59% of all transplants performed over the past 4 years.

Outcomes of repeat endothelial keratoplasty in patients with failed Descemet stripping endothelial keratoplasty.

PURPOSE: To report the outcomes of repeat endothelial keratoplasty (EK) in patients with failed Descemet stripping endothelial keratoplasty (DSEK). METHODS: The clinical records of patients with failed DSEK who underwent repeat EK surgery at a single institution were reviewed. RESULTS: A total of 20 eyes of 20 patients (8 men and 12 women) were included. The mean age at initial DSEK surgery was 69.9 ± 11.9 years (range, 41-83 years). The causes of DSEK failure included progressive endothelial failure (8 eyes; 40%), primary graft failure (8 eyes; 40%), and endothelial rejection (4 eyes; 20%). The mean duration from primary DSEK to repeat EK was 13.1 ± 10.3 months (range, 2-33 months). Removal of the failed DSEK donor disc was performed in all eyes. Mean preoperative corrected distance visual acuity (logMAR) before repeat EK surgery was 1.76, and this improved to 0.5 (P < 0.001) at the final follow-up at 27 months. Three eyes had limited corrected distance visual acuity secondary to ocular comorbidities (age-related macular degeneration and advanced glaucomatous optic neuropathy). CONCLUSIONS: Repeat EK in patients with DSEK failure is an effective treatment modality. This is the preferred management option compared with penetrating keratoplasty because the advantages of EK surgery are maintained with repeat EK surgery.

Shifting trends in bacterial keratitis in Toronto: an 11-year review.

OBJECTIVE: To review the distribution, current trends, and resistance patterns of bacterial keratitis isolates in Toronto over the last 11 years. DESIGN: Retrospective, observational, case series. PARTICIPANTS: Microbiology records of suspected bacterial keratitis cases that underwent a diagnostic corneal scraping and cultures from January 1, 2000, through December 31, 2010, were reviewed. METHODS: Culture results and antibiotic sensitivity profiles were reviewed and analyzed. MAIN OUTCOME MEASURES: Distribution of the main isolated pathogens as well as in vitro laboratory minimum inhibitory concentration testing results to identify resistance patterns. RESULTS: A total of 1701 consecutive corneal scrapings were taken during the 11 years of the study. A pathogen was recovered in 977 samples (57.4%), with bacterial keratitis accounting for 897 of the positive cultures (91.8%). The total number of Gram-positive and Gram-negative isolates was 684 and 213, respectively. We identified a decreasing trend in Gram-positive isolates (P = 0.016). The most common isolate overall was coagulase-negative Staphylococcus (CNS) and the most common Gram-negative bacteria isolated was Pseudomonas aeruginosa. Methicillin-resistant Staphylococcus aureus (MRSA) was present in 1.3% of the S aureus isolates, whereas methicillin-resistant CNS (MRCNS) was present in 43.1% of the CNS isolates. There was a trend toward increasing laboratory resistance to methicillin from 28% during the first 4 years of the study to 38.8% for the last 3 years (P = 0.133). When analyzing the sensitivities of MRSA and MRCNS isolates to other antibiotics, there was resistance to cefazolin and sensitivity to vancomycin in all isolates, whereas resistance to other antibiotics was variable. CONCLUSIONS: There was a significant decrease in the percentage of Gram-positive microorganisms over time. The sensitivity of Gram-negative isolates to tested antimicrobials was >97% response for all the reported antibiotics; this was not the case for Gram-positive isolates, in which resistance to the antibiotics was more common. Methicillin-resistant organisms accounted for 29.1% of all Gram-positive cultures in our series, suggesting that the empiric use of vancomycin in the setting of severe suspected bacterial keratitis may be justified.

Combined topical and intracameral anesthesia for Descemet's stripping automated endothelial keratoplasty.

To evaluate the use of combined topical and intracameral anesthesia for Descemet's stripping automated keratoplasty (DSAEK). This was a retrospective comparative cohort analysis consisting of 10 eyes in 10 consecutive patients undergoing DSAEK surgery with combined topical and intracameral anesthesia. These cases were compared with 21 randomly selected controls during the same time period undergoing DSAEK surgery performed under retrobulbar anesthesia. Incidence of intraoperative and postoperative complications, and endothelial cell counts were compared. In all cases, DSAEK was completed without intraoperative complications. All patients tolerated the procedure well. There were 6 cases of postoperative graft dislocation requiring rebubbling, and no cases of primary failure or endophthalmitis. No significant difference in endothelial cell counts was found at final follow-up. Short-term results suggest that combined topical and intracameral anesthesia is as safe and effective for DSAEK in cooperative patients when compared to retrobulbar anesthesia. It may thereby be an alternative anesthetic modality for patients in whom retrobulbar or peribulbar anesthesia may be risky or contraindicated.

Descemet stripping automated endothelial keratoplasty using infant donor tissue.

PURPOSE: The purpose of this study was to report the outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK) surgery using infant (2 years and younger) donor tissue. METHODS: Retrospective interventional case series of 3 patients. RESULTS: All 3 patients in this series had good visual outcomes and clear DSAEK grafts. The average endothelial cell count (ECC) from infant donors was very high (4239 cells/mm(2)). Similarly, the average postoperative ECC was also high (3359 cells/mm(2)) with a mean endothelial cell loss of 20.9% at 11-month follow-up. One patient remarkably had an ECC of 4065 cells per square millimeter at 1-year follow-up with a net endothelial cell loss of only 13.3%. No difficulties were noted using infant donor tissue, including the intraoperative use of the Moria microkeratome to prepare the DSAEK donor, insertion of the donor graft, or with air-bubble management. CONCLUSIONS: Using infant donor tissue for DSAEK surgery is safe and may be preferable, particularly for younger patients. The higher preoperative endothelial cell densities in infant donor tissue should improve graft survival and long-term maintenance of corneal transparency provided that surgery-related endothelial cell loss is minimized.

Outcomes of Descemet stripping automated endothelial keratoplasty in patients with previous glaucoma drainage device insertion.

PURPOSE: To report the outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK) in patients with a previously inserted glaucoma drainage device (GDD). METHODS: The clinical records of patients who had DSAEK surgery with a history of GDD insertion were reviewed. RESULTS: Eleven eyes of 10 patients (7 men and 3 women) were included. The mean age for DSAEK surgery was 67.2 ± 20.4 years (range, 22-93 years). The mean follow-up after DSAEK surgery was 20.2 ± 10.7 months (range, 3-37 months). Preoperative mean logarithm of the minimum angle of resolution (logMAR)-corrected distance visual acuity was 1.8 ± 0.6 (range, 20/100 to hand motions), and this improved to 0.9 ± 0.8 (range, 20/40 to hand motions) at the final follow-up (P < 0.01). There was no statistical difference in mean pre-DSAEK versus final post-DSAEK intraocular pressure (P = 0.88). Six of 11 eyes (54.5%) had double GDD insertion before DSAEK surgery. GDD tubes were trimmed in 6 eyes (54.5%), and no eyes required further glaucoma surgical intervention after DSAEK surgery. Postoperative complications included early postoperative graft dislocation in 4 eyes (36.4%) that were successfully repositioned. Four eyes (36.4%) had an episode of endothelial rejection, with 2 patients (18.2%) requiring repeat endothelial keratoplasty for endothelial failure. The mean donor endothelial cell count was 2740 cell per square millimeter preoperatively and reduced to 858 cells per square millimeter at the final follow-up, a significant mean reduction of 69%. This was significantly greater than previously reported endothelial cell loss after DSAEK alone at our institution. CONCLUSIONS: Although surgery may be more challenging, the presence of GDD is not a contraindication to DSAEK surgery. In this series, there was a high rate of dislocation that was successfully managed with rebubbling. DSAEK seems to be a reasonable alternative to penetrating keratoplasty for corneal decompensation after GDD.

Outcomes of repeat endothelial keratoplasty in patients with failed deep lamellar endothelial keratoplasty.

PURPOSE: To report the outcomes of repeat endothelial keratoplasty (EK) in patients with previous failed deep lamellar endothelial keratoplasty (DLEK). METHODS: This retrospective interventional case series involved the review of clinical records of patients with failed DLEK surgery who underwent repeat EK surgery. RESULTS: Ten eyes of 9 patients (2 men and 7 women) were included. The mean age at initial DLEK surgery was 71.2 ± 8.0 years (range, 59-80 years), and the duration to repeat EK was 47 ± 14.3 months (range, 16-63 months). Removal of the failed DLEK donor disc was performed in 7 eyes (70%); in 3 eyes (30%), repeat EK was performed without removal of the failed donor disc. The mean follow-up after repeat EK surgery was 21.7 months (range, 3-44 months). Improvements in corneal clarity and visual acuity were obtained in all eyes. Mean preoperative logarithm of the minimum angle of resolution (logMAR) best-corrected visual acuity (BCVA) was 1.46 (20/577; range, 20/100 to counting fingers) and improved to 0.64 (20/87; range, 20/30 to 20/300) at the final follow-up (P = 0.03). Four eyes had limited BCVA secondary to ocular comorbidites, including age-related macular degeneration, cystoid macular edema, and advanced glaucomatous optic neuropathy. No significant postoperative complications were noted after repeat EK surgeries. CONCLUSIONS: Repeat EK in patients with late DLEK failure is effective in improving corneal clarity and is a viable alternative to penetrating keratoplasty (PK). Surgery may be performed with or without removal of the failed donor disc. Visual outcomes may be limited by the existence of ocular comorbidities.

Late-onset Klebsiella oxytoca flap-margin-related corneal ulcer following laser in situ keratomileusis.

A 45-year-old woman developed a spontaneous flap-margin-related corneal ulcer 11 years after the original laser in situ keratomileusis (LASIK) procedure. Two enhancements had been performed; the most recent was 3 years prior to presentation. Cultures were positive for a heavy growth of Klebsiella oxytoca. The ulcer responded clinically to topical treatment with fortified cefazolin. Eighteen days after presentation, the infiltrate had resolved and the cornea had fully epithelialized. To our knowledge, this is the first report of post-LASIK infectious keratitis caused by K oxytoca.

Combined use of subconjunctival and intracorneal bevacizumab injection for corneal neovascularization.

PURPOSE: To report on the safety and clinical use of combined subconjunctival and intracorneal bevacizumab for corneal neovascularization. METHODS: The charts of 12 consecutive patients with corneal neovascularization who received combined subconjunctival and intracorneal injections of bevacizumab (2.5 mg/0.1 mL) were reviewed. Patients received 1 to 3 injections of 2.5 mg of bevacizumab (1.25 mg/0.05 mL subconjunctival and 1.25 mg/0.05 mL intrastromal). Morphological changes were assessed clinically by 1 investigator. RESULTS: Combined subconjunctival and intracorneal injections of bevacizumab were effective and well-tolerated. No significant ocular or systemic adverse events were observed during 6.4 months (range, 0.25-22 months) of follow-up. All patients showed a reduction in the neovascularized area. CONCLUSIONS: Short-term results suggest that combined subconjunctival and intracorneal injections of bevacizumab are an effective method for reducing corneal neovascularization. It may be a useful option or adjunct to other treatments in stabilizing or improving vision.

Hemodialysis graft flow surveillance with prompt corrective interventions improves access long-term patency.

BACKGROUND: Hemodialysis arteriovenous graft (AVG) patency is dependent on favorable flow characteristics. We examined hemodynamic, humoral risk factors, and the effects of stringent flow surveillance coupled with prompt corrective intervention on long-term graft patency. METHODS: Over a 29-month period 92 chronic hemodialysis patients with AVG were evaluated monthly by flow surveillance. Clinical diagnosis of failing graft, which promoted angiography and corrective intervention was based on flow reduction, and patient's unique medical history and hemodynamic parameters. RESULTS: Graft arteriography revealed stenotic lesions in 94.5% of the cases, necessitating endovascular or surgical angioplasty. Low ejection fraction, early postoperative intervention, and low baseline flow were associated with a statistically significant reduction in intervention-free interval (p < 0.05). Mean AVG flow threshold prior to intervention was 463 +/- 154 ml/min, corresponding to a mean flow reduction of 45 +/- 12%. Total graft thrombosis rate was 0.21 thrombotic episodes/patient year. Primary graft patency at 6, 12, and 24 months was 76, 44 and 35%, and secondary patency 99, 97, 88%, respectively. CONCLUSIONS: Stringent flow surveillance policy coupled with prompt intervention has been proven effective in maintaining AVG long-term patency. Patients with decreased ejection fraction, early post-operative intervention, and low baseline AVG flow are prone to graft thrombosis.