Transscleral Cyclophotocoagulation for the Treatment of Uncontrolled Glaucoma in a Boston Keratoprosthesis Type II Patient.

Postoperative endoscopic cyclophotocoagulation (CPC) for the treatment of glaucoma in patients with Boston keratoprosthesis type II (BKPro II) was first described in 2017 by Poon et al. (Endoscopic cyclophotocoagulation for the treatment of glaucoma in Boston keratoprosthesis type ii patient. J Glaucoma. 2017 Apr;26(4):e146-9). As we do not have this device, we present a case of transscleral CPC (TSCPC), in a BKPro II patient who had graft versus host disease and developed uncontrolled glaucoma. We dissected plane by plane to expose the bare sclera and performed the procedure as traditionally described. We concluded that this is a safe, controlled, and effective option in this patient population where the glaucoma treatment options are very limited. To the best of our knowledge, this is the first case report to describe the surgical technique of TSCPC in a BKPro II patient.

Glaucoma After Corneal Trauma or Surgery-A Rapid, Inflammatory, IOP-Independent Pathway.

PURPOSE: To review clinical aspects and cellular and molecular steps in the development of long-term glaucoma after corneal surgery or acute trauma-especially the pivotal role of tumor necrosis factor alpha (TNF-α), the rapidity of the secondary damage to the retinal ganglion cells, and the clinical promise of early antiinflammatory intervention. METHODS: A series of laboratory studies on post-injury and post-surgery glaucoma have been compared to clinical outcome studies on the subject, focusing particularly on the vulnerability of the retinal ganglion cells. Alkali burn to the cornea of mice and rabbits served as the main experimental model. TNF-α titer, ganglion cell apoptosis, and depletion of optic nerve axons have been examined. Anti-TNF-α antibodies or corticosteroids have been used to protect the retinal ganglion cells. Intraocular pressure (IOP) postburn was recorded by manometric methods. RESULTS: In animals with alkali burn to the cornea, damage to the retina can occur within 24 to 72 hours. This is not because of a direct pH change posteriorly-the alkali is effectively buffered at the iris-lens level. Rather, TNF-α (and other inflammatory cytokines), generated anteriorly, rapidly diffuses posteriorly to cause apoptosis of the ganglion cells. During this time, the IOP remains much lower than the reported values required to cause ganglion cell damage. The TNF-α antibody infliximab or corticosteroids, if administered promptly, are markedly protective of the ganglion cells. CONCLUSIONS: A rapidly initiated, inflammatory (TNF-α mediated), IOP-independent pathway to glaucoma, resulting from acute anterior segment trauma or surgery, has been identified in laboratory studies. Prompt prophylactic treatment with antiinflammatory agents has been shown to be markedly neuroprotective of retinal ganglion cells, presumably capable of reducing the risk of late glaucoma.

Comparing capsular bag performance of a hydrophilic and a hydrophobic intraocular lens: A randomised two-centre study.

PURPOSE:: To evaluate the capsular bag performance and posterior capsule opacification development of two intraocular lenses differing in material and design. METHODS:: This study included patients who were scheduled for cataract surgery and compared a hydrophilic intraocular lens (Super flex® intraocular lens; Rayner Surgical, Worthing, UK) with a hydrophobic intraocular lens (AcrySof® SA60AT; Alcon, Fort Worth, TX, USA). Follow-ups were performed 1 month and 2 years after cataract surgery, including a slit lamp examination and retroillumination images. RESULTS:: In total, 80 eyes of 80 patients were recruited. At the 1-month follow-up, 6 of 39 cases had a gap between the posterior lens capsule and intraocular lens (1 case in the hydrophilic intraocular lens group and 5 cases in the hydrophobic intraocular lens group; p = 0.348). Objective and subjective posterior capsule opacification scoring showed no statistically significant difference between both groups (p = 0.123). CONCLUSION:: Both intraocular lens showed a good capsular bag performance and a relatively low posterior capsule opacification development within the first 2 years after surgery.

Chemical Burns of the Eye: The Role of Retinal Injury and New Therapeutic Possibilities.

PURPOSE: To propose a new treatment paradigm for chemical burns to the eye - in the acute and chronic phases. METHODS: Recent laboratory and clinical data on the biology and treatment of chemical burns are analyzed. RESULTS: Corneal blindness from chemical burns can now be successfully treated with a keratoprosthesis, on immediate and intermediate bases. Long term outcomes, however, are hampered by early retinal damage causing glaucoma. New data suggest that rapid diffusion of inflammatory cytokines posteriorly (TNF-α, etc) can severely damage the ganglion cells. Prompt anti-TNF-α treatment is markedly neuroprotective. Long term profound reduction of the intraocular pressure is also vital. CONCLUSION: A new regimen, in addition to standard treatment, for severe chemical burns is proposed. This involves tumor necrosis factor alpha (TNF-α) inhibition promptly after the accident (primarily for retinal neuroprotection), prophylactic maximal lowering of the intraocular pressure (starting immediately), and keratoprosthesis implantation in a later quiet state.

Methods for assessing forward and backward light scatter in patients with cataract.

PURPOSE: To compare objective methods for assessing backward and forward light scatter and psychophysical tests in patients with cataracts. SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom. DESIGN: Prospective case series. METHODS: This study included patients scheduled for cataract surgery. Lens opacities were grouped into predominantly nuclear sclerotic, cortical, posterior subcapsular, and mixed cataracts. Backward light scatter was assessed using a rotating Scheimpflug imaging technique (Pentacam HR), forward light scatter using a straylight meter (C-Quant), and straylight using the double-pass method (Optical Quality Analysis System, point-spread function [PSF] meter). The results were correlated with visual acuity under photopic conditions as well as photopic and mesopic contrast sensitivity. RESULTS: The study comprised 56 eyes of 56 patients. The mean age of the 23 men and 33 women was 71 years (range 48 to 84 years). Two patients were excluded. Of the remaining, 15 patients had predominantly nuclear sclerotic cataracts, 13 had cortical cataracts, 11 had posterior subcapsular cataracts, and 15 had mixed cataracts. Correlations between devices were low. The highest correlation was between PSF meter measurements and Scheimpflug measurements (r = 0.32). The best correlation between corrected distance visual acuity was with the PSF meter (r = 0.45). CONCLUSIONS: Forward and backward light-scatter measurements cannot be used interchangeably. Scatter as an aspect of quality of vision was independent of acuity. Measuring forward light scatter with the straylight meter can be a useful additional tool in preoperative decision-making.

Determinants of Ocular Pain Severity in Patients With Dry Eye Disease.

PURPOSE: To quantify the severity of ocular pain in patients with dry eye disease (DED) and evaluate factors associated with pain severity. DESIGN: Cross-sectional study. METHODS: Eighty-four patients with DED were asked to score their severity level of ocular pain using a 10-point scale, with 10 indicating the most severe pain. All patients also had a comprehensive ophthalmic assessment including a detailed history, Ocular Surface Disease Index (OSDI) questionnaire, and ocular surface examination. Regression analysis was used to determine the factors associated with ocular pain severity. RESULTS: The mean OSDI score was 45.6 ± 23.1. At least some degree of ocular pain (score >1) was reported by 88.1% of patients, including mild pain (scores 2-4) in 46.4%, moderate pain (scores 5-7) in 34.5%, and severe pain (scores 8-10) in 7.1% of patients. Ocular pain levels significantly correlated with the OSDI score (rs = 0.49, P < .001). Regression analysis showed that the severity of ocular pain had a significant association with use of antidepressant medications (P = .045) but not with tear breakup time, corneal fluorescein staining, or ocular medications used by patients. In patients without pain, a significant correlation was seen between OSDI and corneal fluorescein staining scores (rs = 0.67, P = .01). However, such a correlation was not observed in those with ocular pain. CONCLUSIONS: A majority of patients with DED report some degree of ocular pain, which correlates only moderately with the OSDI score. Severity of ocular pain correlates with nonocular comorbidities such as use of antidepressant medications rather than with clinical signs of DED.

Patients' Perceived Treatment Effectiveness in Dry Eye Disease.

PURPOSE: Patients' perceptions of the effectiveness of a treatment, or perceived treatment effectiveness (PTE), play an important role in medicine. This study aimed to evaluate patients' PTE in dry eye disease (DED) and investigate factors contributing to these patients' perceptions. METHODS: This cross-sectional study included 66 patients with DED. At enrollment, all patients had comprehensive ophthalmic assessment. In addition, to evaluate the patient's PTE, they were asked to use a 10-point scale ranging from "strongly disagree (score 1)" to "strongly agree (score 10)" to score their views on whether their DED treatments had been effective. Changes in clinical parameters of DED over time during their care were also evaluated retrospectively and correlated with the patients' PTE. RESULTS: The mean age of patients was 55.7 years; 79% were women. Regarding patients' PTE, 36.4% strongly (score 10) and 53.0% moderately (scores 6-9) believed that their DED treatment had been effective. However, 10.6% thought that their treatment had not been effective (scores 1-5). Less favorable PTE for the DED treatment was significantly associated with a younger age (P < 0.001), current use of antidepressant medications (P = 0.01), and a higher Ocular Surface Disease Index score (P = 0.01) at enrollment. CONCLUSIONS: A majority of patients with DED have positive perceptions regarding the effectiveness of their treatments. Less favorable perceptions are associated with more severe ocular symptoms and nonocular parameters such as younger age and current antidepressant use. In DED management, assessing patients' PTE should be considered as an important part of clinical practice.

Infliximab after Boston Keratoprosthesis in Stevens-Johnson Syndrome: An Update.

PURPOSE: To report our experience using intravenous infliximab for the treatment of tissue melt after Boston keratoprosthesis (B-KPro) types I and II in patients with autoimmune disease. METHODS: Case series. RESULTS: We identified four patients who were treated with intravenous infliximab in the context of tissue melt after B-KPro. Stevens-Johnson syndrome-associated corneal blindness was the primary surgical indication for B-KPro implantation in all patients. Two patients received a B-KPro type I and two patients received a B-KPro type II. The patients received intravenous infliximab for skin retraction around B-KPro type II, melting of the carrier graft or leak. Treatment resulted in a dramatic decrease in inflammation and, in some cases, arrest of the melting process. Cost and patient adherence were limiting factors to pursuing infliximab therapy. In addition, one patient developed infusion reactions. CONCLUSIONS: Intravenous infliximab may be considered as globe- and sight-saving therapy for tissue melt after B-KPro.

The Role of the Back Plate in Angle Anatomy with the Boston Type I Keratoprosthesis.

PURPOSE: To quantitatively evaluate the angle anatomy in eyes with the Boston type I keratoprosthesis (B-KPro) differing in the back plate (BP) material and size using anterior segment optical coherence tomography. METHODS: B-KPro eyes with poly(methyl methacrylate) (PMMA) (7.0 and 8.5 mm) and titanium (7.0, 8.5, and 9.5 mm) BPs were imaged with anterior segment optical coherence tomography. The angle opening distance at 500 µm from the scleral spur (AOD500), trabecular iris surface area at 500 µm from the scleral spur (TISA500), and trabecular iris angle at 500 µm from the scleral spur (TIA500) were measured. Among the visible quadrants, the average, the temporal, the widest, and the narrowest angle of each eye were included in the analysis. Average time between B-KPro implantation and imaging was 7.5 ± 1.4 years for a PMMA BP and 2.4 ± 2.3 years for a titanium BP (P < 0.0001). RESULTS: We analyzed 17 B-KPro eyes with PMMA BPs and 24 B-KPro eyes with titanium BPs. The average AOD500 (394.1 ± 226.9 vs. 454.5 ± 255.6 µm, P = 0.44), average TIA500 (26.2 ± 14.2 vs. 29.8 ± 13.9 degrees, P = 0.43), and average TISA500 (0.15 ± 0.08 vs. 0.17 ± 0.10 µm, P = 0.52) were not statistically different between eyes with PMMA and titanium BPs, nor were the temporal, the narrowest, and the widest angle measurements of each eye (all P > 0.05). Similarly, no significant differences were found between the angle measurements of B-KPro eyes with a titanium BP diameter of 8.5 or 9.5 mm (all P > 0.05). CONCLUSIONS: We successfully visualized the angle anatomy in 66.1% of the imaged eyes, including all BPs studied. Neither the material nor the size of the B-KPro BP had a significant impact on the angle anatomy.

Patients' Perspectives on Their Dry Eye Disease.

PURPOSE: Although it has been known that patients' perspectives on their disease can significantly affect their level of functional disability as well as disease outcome, limited data are available on patients' perceptions of their dry eye disease (DED). The aim of this questionnaire-based study was to evaluate patients' perspectives on their DED. METHODS: This cross-sectional study included 91 patients with DED. In addition to clinical evaluation, all patients completed a questionnaire to evaluate their perspectives on their DED. This included their satisfaction with understanding DED, their opinion on the easiness of following doctors' advice, their opinion on the effectiveness of the treatment, their satisfaction with the eye care, and their general outlook on DED. RESULTS: This study included 75 (82%) women and 16 men (18%) with a mean age of 57 ± 14 years who had been treated for DED for 5.2 ± 5.4 years. 93% of the patients were satisfied with their understanding of DED, and 76% found it easy to follow their doctors' advice for DED management. Furthermore, 95% thought that the DED treatment had been helpful and 95% were satisfied with their eye care for DED. Forty-eight percent expressed optimism regarding the long-term prospects of their DED. CONCLUSIONS: Although the majority of DED patients have positive perspectives on their disease, close to half report a lack of optimism regarding the long-term outlook for their condition.

Effect of Penetrating Keratoplasty and Keratoprosthesis Implantation on the Posterior Segment of the Eye.

PURPOSE: To compare the effects of post-penetrating keratoplasty (PK) and post-keratoprosthesis (KPro) surgery-related inflammation on the posterior segment of the eye and to assess inhibition of tumor necrosis factor alpha (TNFα) and interleukin-1 beta (IL-1ß) on these effects. METHODS: BALB/C (syngeneic) or C57BL/6 (allogeneic) corneas were transplanted onto BALB/C host beds as part of PK or miniature KPro (m-KPro) implantation. Intraocular pressure (IOP) was measured via an intracameral pressure sensor; tissues were harvested and analyzed 8 weeks after surgery. Expression of TNFα and IL-1ß in the retina was analyzed using real-time quantitative (q)PCR. Optic nerve degeneration (axon count, circularity, and area) was assessed quantitatively using ImageJ software. After m-KPro implantation, mice were treated with saline, anti-TNFα, or anti-IL-1ß antibody, and axonal loss was assessed after 10 weeks. RESULTS: Mean IOP was within normal limits in the operated and fellow eyes in all groups. The mRNA expression of TNFα and IL-1ß was highest in m-KPro groups with either syngeneic or an allogeneic carrier. We observed optic nerve degeneration in both allogeneic PK and m-KPro implanted eyes with an allogeneic carrier. However, TNFα blockade significantly reduced axonal loss by 35%. CONCLUSIONS: Allogeneic PK and m-KPro implants with an allogeneic carrier lead to chronic inflammation in the posterior segment of the eye, resulting in optic nerve degeneration. In addition, blockade of TNFα prevents axonal degeneration in this preclinical model of allogeneic m-KPro (alloKPro) implantation.

Capsular bag performance of a hydrophobic acrylic 1-piece intraocular lens.

PURPOSE: To compare parameters after 1-piece and 3-piece intraocular lens (IOL) implantation. SETTING: Moorfields West End Clinic, London, United Kingdom, and Hanusch Hospital, Vienna, Austria. DESIGN: Prospective randomized controlled trial. METHODS: Each eye of patients having bilateral surgery for age-related cataract was randomized to have implantation of a 1-piece IOL (Tecnis ZCB00) or a 3-piece IOL (Tecnis ZA9003). Changes in visual acuity, refraction, and anterior chamber depth (ACD) were evaluated during a 2-year follow-up. Intraocular lens tilt and decentration were evaluated using a Purkinje meter. Regeneratory posterior capsule opacification (PCO) was analyzed using retroillumination photographs in Automated Quantification of After-Cataract image-analysis software. RESULTS: This study comprised 100 eyes of 50 patients. No statistically significant differences were found in IOL tilt or decentration between groups (P≥.06). Minimal but statistically significant changes were observed in the vertical tilt component 12 months postoperatively in the 3-piece IOL group (P<.01). The tilt and decentration components did not correlate with changes in sphere or the regeneratory PCO score (r = 0.38, P≥.06). The ACD decreased significantly between 1 day and 1 month postoperatively in both groups (P<.01), with no significant changes afterward (P≥.22). The anterior chamber was significantly deeper in the 1-piece group at all follow-up visits (P<.01). CONCLUSIONS: Both the 1-piece IOL and the 3-piece IOL showed excellent positional stability in the capsular bag, resulting in good clinical outcomes. Regeneratory PCO levels were low and comparable between the IOLs. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Idiopathic vitritis in the setting of Boston keratoprosthesis.

PURPOSE: The aim of this study was to revisit the clinical paradigm attributed to Boston keratoprosthesis recipients presenting with idiopathic vitreous inflammation. METHODS: A retrospective chart review was performed of keratoprosthesis recipients at Massachusetts Eye and Ear Infirmary, from January 2000 to August 2013, for demographic data, indication(s) for surgery, timing and presentation of vitreous inflammation, and best-corrected visual acuity at baseline, on presentation, and after resolution of vitritis. RESULTS: Twenty-three (23 eyes) of 346 patients developed idiopathic vitreous inflammation after keratoprosthesis implantation. Six of 23 patients presented with signs and symptoms similar to infectious endophthalmitis but were culture negative. The proportion of patients who fit the previous paradigm of sudden painless loss of vision without external signs of infection ("sterile vitritis") at their first presentation with vitritis was only 4 of 23. Vision decline was variable (median, 9 lines on Snellen chart; range, 0-24), as was time to recovery of best vision (median, 8.9 weeks; range, 0.9-36.7). Nine eyes had repeat bouts (43 episodes in 23 patients). Ten of 43 episodes did not recover to baseline vision. Seventeen of 23 eyes with idiopathic vitritis after keratoprosthesis later developed other complications. CONCLUSIONS: The current paradigm for idiopathic vitritis after keratoprosthesis implantation includes sudden painless loss of vision with full recovery of vision on treatment with periocular corticosteroids. However, idiopathic vitritis after keratoprosthesis can also mimic infectious endophthalmitis with pain and external signs of inflammation. Visual loss can be gradual. Vision may not recover to baseline despite treatment. Vitritis may be a part of a common pathway of chronic inflammation after keratoprosthesis.

Periprosthetic Tissue Loss in Patients With Idiopathic Vitreous Inflammation After the Boston Keratoprosthesis.

PURPOSE: Idiopathic vitritis is a poorly understood complication after Boston keratoprosthesis surgery with unclear etiology. We sought to determine whether an association exists between periprosthetic corneal tissue loss and the development of idiopathic vitritis in keratoprosthesis recipients. METHODS: Thirteen Boston type I keratoprosthesis recipient eyes with a history of idiopathic vitritis and 34 type I keratoprosthesis recipient eyes with no history of idiopathic vitritis underwent anterior segment optical coherence tomography (AS-OCT) at a median time postoperatively of 2.4 years versus 1.9 years (range, 0.5-14.2 vs. 0.1-13.6 years), respectively. Areas of corneal graft tissue loss ("gaps") around the keratoprosthesis stem were identified and analyzed by 2 masked observers. The difference in the presence, number, and size of gaps was compared between cases and controls. RESULTS: A periprosthetic gap was identified more commonly in idiopathic vitritis cases than in controls on AS-OCT (11/13, 86% vs. 11/34, 33.3%, P < 0.001). The number of gaps between cases and controls was also significantly different (2.6 ± 1.6 vs. 0.5 ± 0.8, P < 0.001), but not the estimated gap area (0.056 ± 0.049 mm² vs. 0.039 ± 0.025 mm², P = 0.22). CONCLUSIONS: A significantly higher proportion of keratoprosthesis recipient eyes with idiopathic vitritis had corneal tissue loss around the keratoprosthesis stem than did controls. Tissue loss could serve as an entry point for debris or bacterial components, triggering idiopathic vitritis. Our study underscores the utility of AS-OCT imaging in the postoperative management of keratoprosthesis patients.

Comparison of methods to quantify posterior capsule opacification using forward and backward light scattering.

PURPOSE: To compare forward and backward light scattering measurements to quantify posterior capsule opacification (PCO). SETTING: Vienna Institute for Research in Ocular Surgery, Vienna, Austria. DESIGN: Prospective single-center study. METHODS: This observational study comprised consecutive patients scheduled for neodymium:YAG (Nd:YAG) capsulotomy for regeneratory PCO. The corrected distance visual acuity (CDVA) using Early Treatment of Diabetic Retinopathy Study charts and the contrast sensitivity under mesopic and photopic conditions using Pelli-Robson charts were assessed before an Nd:YAG capsulotomy was performed. Retroillumination images, rotating Scheimpflug scans (Pentacam HR), and straylight meter (C-Quant) and point-spread function (PSF) meter (Optical Quality Analysis System) measurements were performed before and after Nd:YAG capsulotomy. RESULTS: The study enrolled 50 eyes of 50 patients. The mean uncorrected distance visual acuity and CDVA were 0.76 logMAR ± 0.18 (SD) and 0.68 ± 0.2 logMAR, respectively. The mean log contrast sensitivity (logCS) was 1.2 ± 0.15 logCS under photopic conditions and 1.05 ± 0.15 logCS under mesopic conditions. There was a moderate correlation between the Scheimpflug score and the Automated Quantification of After-Cataract score (r(2) = 0.37, P=.03). Furthermore, a moderate and close to significant correlation between the PSF meter and the straylight meter was observed (r(2) = 0.32; P=.07). CONCLUSION: Each of the 4 devices assesses different aspects of a patient's quality of vision. Further developments should focus on methods that measure forward scatter of light in a large visual angle and are not too patient or examiner dependent.

Effect of an aspheric intraocular lens on the ocular wave-front adjusted for pupil size and capsulorhexis size.

PURPOSE: To compare the ocular wave-front of eyes with silicone Intraocular lens (IOLs) with aspheric and spherical optics after cataract surgery, taking into account the patient's pupil size under reading conditions and after pupil dilatation. METHODS: In this institutional prospective, randomized, controlled, patient and examiner masked, bilateral trial with intra-individual comparison, 60 eyes of 30 patients with bilateral age-related cataract were included. Each patient received a spherical IOL (CeeOn Edge, 911A, AMO, Santa Ana, CA, USA) in one eye and an aspheric IOL (Tecnis, Z9000, AMO) in the contra-lateral eye. Exclusion criteria were other ocular pathologies, capsular changes or zonular weakness. The main outcome variable was spherical aberration of the ocular wave-front under mesopic pupil conditions measured 2 years after surgery. Additional outcome variables were visual acuity and photopic and mesopic contrast sensitivity. RESULTS: There was no significant difference in visual acuity between the two IOL types under physiological pupil conditions and also not after pupil dilation. However, spherical aberrations were significantly lower with the aspheric IOL (SA: spherical 0.38 µm, SD: 0.11 µm; aspheric 0.10 µm, SD: 0.13 µm; p < 0.01), and there was a significant difference in contrast sensitivity at 12 cycles/degree. CONCLUSIONS: This is the first randomized and masked trial on visual function and ocular wave-front after implantation with this silicone aspheric IOL, taking the patients' own pupil size into account. The effect on visual function was detectable for mesopic contrast sensitivity, but there was no difference in visual acuity. The SA was found to be significantly lower under physiological pupil conditions as well as when recalculated for the rhexis size and under pharmacological dilatation.

Corneal inflammation after miniature keratoprosthesis implantation.

PURPOSE: To compare corneal inflammation after syngeneic and allogeneic penetrating keratoplasty (PK) with miniature Keratoprosthesis (m-KPro) implantation in mice. METHODS: BALB/C (syngeneic) or C57BL/6 (allogeneic) corneas were transplanted onto BALB/C host beds as part of PK or m-KPro implantation. Corneal inflammation was assessed by determining the frequencies of CD45(+) leukocytes, CD4(+) T cells, CD11b(+) cells, and Gr-1(+) granulocytes/monocytes by flow cytometry at 2, 4, and 8 weeks post transplantation. In addition, expression levels of the proinflammatory cytokines TNF-α and IL-1ß were analyzed using real-time qPCR at 8 weeks post transplantation. RESULTS: Cell frequencies in the syngeneic (syn) and allogeneic (allo) m-KPro groups were higher compared with the syngeneic and allogeneic PK groups, respectively, at all time points. However, after week 4, frequencies of all analyzed immune cells were higher in the alloPK group as compared with synKPro group. At 8 weeks, the expression of TNF-α was higher in synKPro, alloPK, and alloKPro groups compared with the naïve and synPK groups. The expression of IL-1ß was significantly higher in both KPro groups as compared with PK groups. CONCLUSIONS: Although the m-KPro device augments the inflammatory response in the cornea after its implantation, allogenicity (of the carrier tissue) is also a significant contributor to corneal inflammation. These data suggest that using syngeneic or decellularized corneal tissue as a Boston-KPro carrier could reduce the postoperative inflammation response.

Correction of moderate corneal astigmatism during cataract surgery: toric intraocular lens versus peripheral corneal relaxing incisions.

PURPOSE: To compare the astigmatism-reducing effect of a toric intraocular lens (IOL) and peripheral corneal relaxing incisions (PCRIs). SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom. DESIGN: Prospective masked bilateral randomized study. METHODS: Cataract patients with a preoperative corneal astigmatism of 1.0 to 2.5 diopters (D) were included. All patients received a toric IOL in 1 eye and a nontoric IOL plus a PCRI in the other eye. Postoperative follow-up was at 1 hour, 1 month, and 6 months. The uncorrected distance visual acuity, corrected distance visual acuity, autorefraction (Topcon RM-8800), and subjective refraction were recorded. The IOL axis was assessed using retroillumination photographs. RESULTS: The study enrolled 60 eyes of 30 patients. The mean astigmatism vector reduction was 1.74 D ± 0.64 (SD) in the toric IOL group and 1.27 ± 0.76 D in the PCRI group; the difference was statistically significant (P=.042). The mean absolute rotation of the toric IOL was 2.5 ± 1.8 degrees (maximum 6.3 degrees) in the first 6 postoperative months. Astigmatism increased in the PCRI group between the 1-month and 6-month follow-up (mean 0.38 ± 0.27 D; maximum 1.00 D) (P<.001). CONCLUSION: Toric IOLs and PCRIs both reduced astigmatism; however, toric IOLs reduced astigmatism to a higher extent and they were more predictable.

Glaucoma progression and role of glaucoma surgery in patients with Boston keratoprosthesis.

PURPOSE: The aim of this study was to evaluate glaucoma onset and progression after implantation of Boston Keratoprostheses (B-KPro) and the role of glaucoma surgery. METHODS: Records of patients with B-KPro implantation during 2004 to 2009 were reviewed. Parameters relevant to B-KPro surgery and glaucoma status were recorded. The data were analyzed in 5 groups based on the preoperative diagnosis. RESULTS: One hundred six eyes of 87 patients were included, and the average age was 54 ± 6.7 years. Forty-six percent were female. Eighteen eyes had a B-KPro with a titanium back plate, and the others had a poly(methyl methacrylate) back plate. Thirty-three eyes were pseudophakic, and the rest were left aphakic. The follow-up time was 3.3 ± 1.0 years. Indications for implantation included past infection, congenital glaucoma, trauma, autoimmune diseases, aniridia, burns, and others. Sixty-six percent of the eyes had glaucoma preoperatively, and 26% developed de novo glaucoma afterward. The mean intraocular pressure (by finger palpation) was 16.5 ± 5.7 mm Hg. Reliable visual field tests were only available in 59% of the eyes; hence, the cup-to-disc ratio of the optic nerve head was used as the main outcome measure. In B-KPro-implanted eyes with glaucoma, 65% had undergone glaucoma surgery at some point, and 30% did not show progression. Thirty-one percent of the total cohort had disc pallor with a cup-to-disc ratio of <0.8. CONCLUSIONS: Glaucoma in B-KPro remains a challenge, despite aggressive attempts to slow down its progression. Patients with glaucoma before B-KPro implantation should be considered for glaucoma surgery before or simultaneously with B-KPro implantation. The high number of eyes with disc pallor suggests that additional mechanisms other than elevated intraocular pressure may play a role in optic neuropathy.

A novel murine model for keratoprosthesis.

PURPOSE: To establish a murine model for keratoprosthesis. METHODS: A miniature keratoprosthesis (m-KPro) device was created consisting of a poly[methyl methacrylate] front part and a titanium back plate, designed after the Boston KPro, which is in widespread clinical use. BALB/c mice were used and a 2 mm in diameter donor cornea was punched out. After 2-mm trepanation of the syngeneic recipient cornea, extracapsular crystalline lens extraction was performed. The m-KPro was assembled onto the cornea button in a similar manner to human KPro implantation. The cornea-device complex was secured to the recipient bed with eight interrupted 11-0 sutures. All mice (n = 10) were followed up for 8 weeks postoperatively. RESULTS: All m-KPros were successfully implanted and retained in all 10 animals. There were no critical complications such as endophthalmitis, corneal melting, device extrusions, leakage, extensive inflammation, or weight loss in the animals. We observed mild to moderate donor and host corneal neovascularization in all cases throughout the follow-up period. CONCLUSIONS: We have established a novel murine model of KPro implantation that we anticipate will serve as a good experimental system for evaluating host responses after KPro surgery.