Maria S. Cortina

Visual outcomes of Boston keratoprosthesis implantation as the primary penetrating corneal procedure.

Purpose: To report the short-term visual outcomes and complications of keratoprosthesis surgery as the primary penetrating corneal procedure for patients at high risk for conventional corneal transplantation. Methods: A retrospective chart review was conducted of 21 eyes of 19 patients who underwent either Boston keratoprosthesis type I or type II as the primary penetrating corneal procedure from February 2007 to March 2011. Results: Nineteen type I (90.5%) and 2 type II (9.5%) Boston keratoprosthesis procedures were performed in 19 patients. Mean follow-up was 14.6 months (range, 6–36.3 mo). Primary indications for surgery included chemical or thermal injury, aniridia, and Stevens–Johnson syndrome. Preoperative best-corrected visual acuity (BCVA) ranged from 20/100 to light perception and was count fingers or worse in 20 eyes (95.2%). At last follow-up for all eyes, 15 eyes (71.4%) achieved BCVA ≥20/200 and 4 eyes (19%) improved to BCVA ≥20/50. No intraoperative complications occurred. Postoperative complications include retroprosthetic membrane formation (47.6%), cystoid macular edema (33.3%), elevated intraocular pressure (23.8%), glaucoma progression (14.3%), and endophthalmitis (4.8%). The initial keratoprosthesis was retained in 19 eyes (90.5%). Conclusion: The Boston keratoprosthesis, based on early follow-up, is a good alternative as a primary penetrating corneal procedure in a select group of patients with very poor prognosis for penetrating keratoplasty. Although complications can occur and require close monitoring, visual acuity significantly improved in the majority of patients.

Neuroprotectin D1 Restores Corneal Nerve Integrity and Function After Damage From Experimental Surgery

PURPOSE To investigate if topical treatment of neuroprotectin D1 (NPD1) increases regeneration of functional nerves after lamellar keratectomy. METHODS An 8-mm stromal dissection was performed in the left eye of each rabbit. The rabbits were treated with NPD1, pigment epithelial-derived factor (PEDF) in combination with docosahexaenoic acid (DHA) or vehicle for 6 weeks, and corneas were obtained at 8 weeks. After fixation, corneal wholemounts were stained with mouse monoclonal anti-βIII-tubulin antibody and double stained with chicken anti-calcitonin gene-related peptide (CGRP) antibody. Corneal sensitivity and tear secretion were measured using the Cochet-Bonnet esthesiometer and the Schirmers test, respectively. Additional rabbits were treated with NPD1, PEDF+DHA, or vehicle, and corneal sections were stained with a rat monoclonal anti-neutrophil antibody. Cultures of trigeminal ganglia from 5-day-old mice were treated with NPD1, PEDF+DHA, lipoxin A4 (LXA4), 12- or 15-hydroxyeicosatetraenoic acid (12[S] or 15[S]-HETE), and nerve growth factor (NGF) as positive control. RESULTS NPD1 increased subepithelial corneal nerve area three times compared with vehicle-treated rabbits. The effect was similar to PEDF+DHA-treated animals. There was recovery of CGRP-positive neurons and an increase in corneal sensitivity and tear secretion in NPD1-treated animals. NPD1 decreased neutrophil infiltration after 2 and 4 days of treatment. In the in vitro cultures, NPD1 and PEDF+DHA induced a 3-fold increase in neurite outgrowth compared with cultures without supplementation. Treatments with LXA4, 12(S)-, and 15(S)- HETE did not stimulate neurite outgrowth. CONCLUSIONS NPD1 has anti-inflammatory and nerve regenerative properties. This study demonstrates that NPD1 may offer an effective treatment for neurotrophic corneas.

Docosahexaenoic acid, protectins and dry eye.

Purpose of reviewTo report recent data on the potential role of omega-3 fatty acids, in particular docosahexaenoic acid and its derivatives, in the treatment of dry eye syndrome. Recent findingsDietary supplementation with polyunsaturated fatty acids yields positive results in the improvement of dry eye signs and symptoms. Although several studies have shown this, evidence is still lacking as to which fatty acid or what combination constitutes the most effective treatment. Studies show that treatment with alpha-linoleic acid reduces dry eye-induced inflammation. Eicosapentaenoic acid and docosahexaenoic acid derivatives, particularly resolvin E1 (RvE1) and neuroprotectin D1, appear to be responsible for docosahexaenoic acids anti-inflammatory effect. This is supported in a study in which topical RvE1 resulted in decreased inflammation in a mouse dry eye model. Topical administration of pigment epithelium-derived factor in combination with docosahexaenoic acid accelerates the regeneration of corneal nerves after their damage during corneal surgery, promoting the return of sensitivity and reducing the signs of dry eye. This combined treatment also reduces objective signs of dry eye, such as rose bengal staining. SummaryNo firm recommendations can be made regarding optimal dietary supplementation of essential fatty acids that benefit dry eye patients. On the basis of animal data and preliminary human studies, docosahexaenoic acid and its derivatives appear to be a safe, effective topical treatment for dry eye patients. This may result from their role in the resolution of inflammation and the regeneration of damaged corneal nerves.

Serial Analysis of Anterior Chamber Depth and Angle Status Using Anterior Segment Optical Coherence Tomography After Boston Keratoprosthesis.

Purpose: To analyze iris behavior and angle status using serial anterior segment optical coherence tomography (AS-OCT) after Boston keratoprosthesis (KPro). Methods: A prospective cases series consisted of 11 eyes with implanted type 1 KPro at a tertiary care institution. The patients underwent preoperative and serial postoperative AS-OCT imaging. The main outcome measures included anterior chamber angle (ACA) at representative meridians (0 degrees, 45 degrees, 90 degrees, 135 degrees, 180 degrees, 225 degrees, 270 degrees, and 315 degrees), grading of total ACA as open (>10 degrees), shallow (≥1 degrees and ⩽10 degrees) or closed (<1 degrees), preoperative anterior chamber depth (ACD), postoperative anatomical and functional ACD, and the presence of iris-back plate touch and peripheral anterior synechiae. Results: The mean follow-up with serial AS-OCT was 13.1 months. Preoperatively, 54.5%, 27.3%, and 18.2% of the eyes had open, shallow, and closed angles, respectively. The mean change in the effective ACD decreased postoperatively by 1.61 mm. At 0 degree and 180 degree meridians, the ACA decreased by a mean change of 6.95 degrees and 8.40 degrees, with a mean change of 8.12 degrees for all meridians. Eight (72.7%) eyes had synechiae with 7.3 and 6.7 clock hours of peripheral anterior synechiae and iris-back plate touch. At the last follow-up, 7 (63.6%) eyes had considerable progression of angle closure (change in grading of total angle), and 18.2%, 36.4%, and 45.5% had open, shallow, and closed angles, respectively. Conclusions: KPro implantation induced progressive angle closure, shallowing of the anterior chamber, and synechiae formation that is not visible on clinical examination. Serial AS-OCT plays an important role in the detection and monitoring of progressive angle closure, and clinical correlation is needed to assess the association with glaucoma development or progression.

Anterior Segment Optical Coherence Tomography for the Quantitative Evaluation of the Anterior Segment Following Boston Keratoprosthesis

Objective To quantitatively evaluate the anterior segment using anterior segment optical coherence tomography (AS-OCT) following Boston keratoprosthesis type 1. Methods A retrospective study consisted of AS-OCT imaging at a single time point postoperatively in 52 eyes. Main outcomes measures include anatomical and functional anterior chamber depth (ACD), angle (ACA) and peripheral and proximal synechiae. Results The mean time point of imaging was 19.3 months postoperatively. Average anatomical and functional ACD was 2.0 and 0.21 mm respectively, and mean ACA ranged from 2.5° to 6.14° in representative meridians. An average of 8.7 clock hours of angle closure was observed in the 25 eyes in which all meridians were imaged. The majority of eyes showed peripheral (86.5%) and proximal (67.3%) synechiae. Conclusions AS-OCT is a useful tool for quantitative evaluation of anterior segment and angle after keratoprosthesis, which is otherwise poorly visible. The majority of eyes showed shallow ACD, extensive angle closure and synechiae formation.

Contact lens surveillance cultures in boston type 1 keratoprosthesis patients

Objectives: To describe surveillance cultures of bandage contact lenses (BCL) in patients with a history of Boston type 1 keratoprosthesis (KPro) surgery. Methods: An institutional review board–approved retrospective review of patients with a history of Boston type 1 KPro surgery and BCL cultures between July 2008 and June 2010. Data on demographics, preoperative diagnosis, topical corticosteroid and antibiotic use, duration of BCL wear, clinical diagnosis of microbial keratitis or endophthalmitis, and culture results were recorded. Results: There were 14 patients (15 eyes) who underwent Boston type 1 KPro between July 2008 and June 2010 with BCL culture data. Ten eyes showed positive growth and one eye developed an infection. Thirty-four cultures were performed and 12 were positive. The most common organism cultured was coagulase-negative staphylococcus (CoNS). Positive cultures, colonization by non-CoNS pathogens, and infection occurred more frequently in patients with an ocular history of autoimmune disease or chemical burn. The growth of 15 or more CoNS colonies occurred only in patients not on vancomycin. An antibiotic was added to the regimen in response to positive cultures for three patients. Conclusions: Contact lens surveillance cultures may provide valuable information on the characteristics of microbial colonization, particularly in highlighting inflammatory disease and disuse of vancomycin as possible risk factors. Bandage contact lenses cultures also have the potential to be useful adjuncts in the clinical management of antibiotic therapy.

Contact Lens Use in Patients With Boston Keratoprosthesis Type 1: Fitting, Management, and Complications.

Abstract: The Boston type 1 keratoprosthesis (KPro) is the most commonly used artificial cornea worldwide. Long-term bandage contact lenses are the standard of care for patients with these devices. The goal of bandage contact lenses is to maintain hydration and to protect the corneal tissue that surrounds the anterior plate of the keratoprosthesis which is vulnerable to desiccation, epithelial breakdown, dellen formation, and corneal melt. Contact lenses can also improve comfort, correct refractive errors, and improve the cosmesis of patients with artificial corneas. However, the continuous use of contact lenses places these patients at risk for complications such as lens loss, lens deposits, chronic conjunctivitis, and infection. In addition, obtaining an adequate fit in a patient with a compromised ocular surface and history of multiple surgeries including glaucoma drainage devices can present a challenge. This review discusses the types of contact lenses used, special fitting considerations, and common complications in patients with previous KPro surgery.

Outcomes of pars plana glaucoma drainage implant in Boston type 1 keratoprosthesis surgery.

Purpose:Glaucoma drainage implantation in conjunction with Boston Type 1 Keratoprosthesis placement is a surgical option in controlling postoperative glaucoma. The purpose of this study is to report outcomes of combined pars plana vitrectomy and glaucoma drainage implantation with corneal patch graft in Boston Type 1 Keratoprosthesis patients. Patients and Methods:A retrospective review of patients who underwent pars plana glaucoma drainage implantation in combination with Boston Type 1 Keratoprosthesis was performed. Preoperative and postoperative parameters collected and analyzed included: visual acuity, intraocular pressure, number of glaucoma medications to achieve intraocular pressure control, bandage contact lens fit, and postoperative complications. Results:Twenty eyes of 20 patients were identified; 95% had preoperative diagnosis of glaucoma, utilizing on an average 2.5 medications with an average intraocular pressure of 19.8 mm Hg (±6.3 mm Hg; range, 9 to 32.8 mm Hg). After placement of the pars plana glaucoma drainage implant, an average intraocular pressure of 19 mm Hg (±7.0 mm Hg; range, 8 to 30 mm Hg) by scleral pneumotonometry was achieved and 85% were deemed to have normal pressures by digital palpation. An average of 2.1 intraocular pressure-lowering medications were required on last follow-up. Average follow-up was 31.6 months (±17.4 mo; range, 12.3 to 71.6 mo). Two eyes required glaucoma drainage implant explantation: one eye due to endophthalmitis from a nonhealing corneal ulcer and the other eye due to corneal melt. None of our patients experienced conjunctival erosion over a pars plana positioned glaucoma drainage implant or tube. Conclusions:For the long-term management of glaucoma in keratoprosthesis patients, a posteriorly placed pars plana glaucoma drainage implant with corneal patch graft in conjunction with keratoprosthesis has a low risk of erosion and postoperative complications.

Histopathological and Immunohistochemical Analysis of Melt-Associated Retroprosthetic Membranes in the Boston Type 1 Keratoprosthesis

IMPORTANCE Retroprosthetic membrane (RPM) formation is the most common complication associated with the Boston type 1 keratoprosthesis and has been associated with corneal melt. OBJECTIVE To identify the histological and immunohistochemical characteristics of RPMs associated with corneal melt. DESIGN, SETTING, AND PARTICIPANTS Observational histopathological case series at a tertiary eye care referral center among patients who underwent Boston type 1 keratoprosthesis explantation because of donor corneal melt at the Illinois Eye and Ear Infirmary between January 1, 2011, and January 1, 2012. EXPOSURES Seven RPM specimens from 7 eyes were stained with hematoxylin-eosin, cytokeratin 7, cytokeratin AE1/3, smooth muscle actin, vimentin, and CD34. Light microscopy was used to evaluate specimens for inflammation and epithelial ingrowth. XY-karyotyping using fluorescence in situ hybridization was performed on 4 specimens with known donor-recipient sex mismatch. MAIN OUTCOMES AND MEASURES Histological and immunohistochemical characteristics of RPMs. RESULTS Inflammatory cells were present in 4 of 7 RPMs. In 3 of 4 sex-mismatched specimens, tissue XY-karyotyping of the RPM interphase cells was consistent with the host sex karyotype. The fourth specimen showed a mixture of recipient-type and donor-type cells. CONCLUSIONS AND RELEVANCE Melt-associated RPMs show variable degrees of inflammation. Most membranes seem to originate from a proliferation of host cells, but donor tissue may contribute in some cases.

Safety of femtosecond laser-assisted cataract surgery performed by surgeons in training.

Femtosecond laser-assisted cataract surgery has grown in popularity among ophthalmologists as a novel technique with the potential to reduce phacoemulsification energy requirements.1,2 However, early adoption of femtosecond laser-assisted cataract surgery by experienced cataract surgeons has been associated with a significant learning curve.3 Roberts et al. reported higher complication rates in the first 200 cases of femtosecond laser-assisted cataract surgery compared to 1,300 subsequent cases at a single high-volume practice.3 Given the challenges faced by experienced surgeons adopting femtosecond laser-assisted cataract surgery, it is unclear whether it can be safely performed by residents in training. We describe our experience with incorporating femtosecond laser-assisted cataract surgery in resident and fellow surgical training. After receiving Institutional Review Board approval, we performed a retrospective case–control study of resident and fellow outcomes with femtosecond laserassisted versus manual cataract surgery. All cataract surgeries performed at our institution from June 2012 to September 2013 by third-year residents and fellows with no prior femtosecond laser-assisted cataract surgery experience were identified. Cases performed without a femtosecond laser were included as manual cases. Cases in which wound construction, anterior capsulotomy, and lens fragmentation were performed using the LenSx femtosecond laser platform (Alcon Laboratories, Inc., Fort Worth, TX) were included as femtosecond laser-assisted cases. Cases were excluded if there was no documentation of intraoperative phacoemulsification parameters or if the case was not staffed by a corneal specialist experienced in femtosecond laser-assisted cataract surgery. Complications and phacoemulsification parameters, including phacoemulsification times, cumulative dissipated energy, aspiration time, and irrigation fluid use were compared between femtosecond laser-assisted and manual cases using a t test. In total, 62 femtosecond laser-assisted and 128 manual cataract surgery cases met inclusion criteria. There was no statistical difference in mean age (P = .12) or cataract grade (P = .31) between the two groups. Successful docking was achieved in 96.8% of eyes scheduled for femtosecond laser-assisted cataract surgery. Attending assistance was required in 46.8% of those eyes. Mean irrigation fluid use and cumulative dissipated energy were 22.5% and 38.2% higher, respectively, for manual cases (P ≤ .001). Total ultrasound, phacoemulsification, torsional, and aspiration times were all statistically higher in manual cases (P < .01) (Figure 1). In a sub-analysis excluding fellow cases, cumulative dissipated energy, fluid use, and phacoemulsification and torsional times remained statistically higher in manual cases despite the smaller sample size (P ≤ .03). In total, four posterior capsular tears and one burn wound occurred in the manual group. No posterior capsular tears or burn wounds occurred in the femtosecond laser-assisted group. This pilot study suggests that femtosecond laserassisted cataract surgery can be safely incorporated in resident and fellow surgical training. Given the high success rate (96.8%), docking was not a problem for residents performing femtosecond laser-assisted cataract surgery. Overall, the complication rate for manual cases (7.0%) was consistent with published rates for residents.4-6 However, surprisingly, fewer complica-