Challenges in management of the Boston Keratoprosthesis Type 1.

PURPOSE OF REVIEW: The Boston Keratoprosthesis Type 1 was pioneered by Claes Dohlman several decades ago. Since its inception, the device has undergone multiple revisions to address challenges associated with retroprosthetic membrane formation, retention, extrusion, stromal melt and endophthalmitis. Although visual outcomes and retention rates have improved, challenges, especially glaucoma, remain. RECENT FINDINGS: The Boston Keratoprosthesis Type I device has seen an increase in popularity because of the improvement in rates of retention and visual rehabilitation. Recent outcome studies have allowed clinicians to identify diagnoses and indications that can lead to more favorable results with the Boston Keratoprosthesis Type I device. SUMMARY: The Boston Keratoprosthesis Type I device continues to play a vital role in visual rehabilitation for eyes with very low chance of realistic allograft survival -- such as in eyes where corneal grafting is considered high-risk: eyes with corneal limbal stem cell failure, extensive deep corneal stromal neovascularization, and multiple allograft failures. This review article summarizes the perioperative and postoperative challenges, as well as other considerations associated with the device.

Donor, Recipient, and Operative Factors Associated With Increased Endothelial Cell Loss in the Cornea Preservation Time Study.

Importance: Determining factors associated with endothelial cell loss after Descemet stripping automated endothelial keratoplasty (DSAEK) could improve long-term graft survival. Objective: To evaluate the associations of donor, recipient, and operative factors with endothelial cell density (ECD) 3 years after DSAEK in the Cornea Preservation Time Study. Design, Setting, and Participants: This cohort study was a secondary analysis of data collected in a multicenter, double-masked, randomized clinical trial. Forty US clinical sites with 70 surgeons participated, with donor corneas provided by 23 US eye banks. Individuals undergoing DSAEK for Fuchs dystrophy or pseudophakic/aphakic corneal edema were included. Interventions: The DSAEK procedure, with random assignment of a donor cornea with a preservation time of 0 to 7 days or 8 to 14 days. Main Outcomes and Measures: Endothelial cell density at 3 years as determined by a reading center from eye bank and clinical specular or confocal central endothelial images. Results: The study included 1090 participants (median age, 70 years) with 1330 affected eyes (240 bilateral cases [22.0%]), who underwent DSAEK for Fuchs dystrophy (1255 eyes [94.4%]) or pseudophakic/aphakic corneal edema (PACE) (75 eyes [5.6%]). Of these, 801 eyes (60.2%) belonged to women and 1207 (90.8%) to white individuals. A total of 749 participants (913 eyes; 164 [21.9%] bilateral cases) had functioning grafts with acceptable endothelial images preoperatively and at 3 years postoperatively and were included in this analysis. Factors associated with a lower ECD at 3 years (estimated effect with 99% CI) in the final multivariable model included donors with diabetes (-103 [-196 to -9] cells/mm2), lower screening ECD (-234 [-331 to -137] per 500 cells/mm2), recipient diagnosis of PACE (-257 [-483 to -31] in cells/mm2), and operative complications (-324 [-516 to -133] in cells/mm2). Endothelial cell loss (ECL) from a preoperative measurement to a 3-year postoperative measurement was 47% (99% CI, 42%-52%) for participants receiving tissue from donors with diabetes vs 43% (99% CI, 39%-48%) without diabetes; it was 53% (99% CI, 44%-62%) for participants diagnosed with PACE vs 44% (99% CI, 39%-49%) for those diagnosed with Fuchs dystrophy, and 55% (99% CI, 48%-63%) in participants who experienced operative complications vs 44% (99% CI, 39%-48%) in those who did not. No other donor, recipient, or operative factors were significantly associated with 3-year ECD. Conclusions and Relevance: Donor diabetes, lower screening ECD, a PACE diagnosis in the recipient, and operative complications were associated with lower ECD at 3 years after DSAEK surgery and may be associated with long-term graft success. While causation cannot be inferred, further studies on the association of donor diabetes and PACE in recipients with lower 3-year ECD warrant further study.

Corneal transplantation at Tenwek Hospital, Kenya, East Africa: Analysis of outcomes and associated patient socioeconomic characteristics.

PURPOSE: To review the graft survival rate, visual outcomes, and patient demographics of primary penetrating keratoplasty performed at Tenwek Hospital, a mission hospital in rural Kenya. METHODS: A retrospective review was performed of the clinical records of patients who underwent primary penetrating keratoplasty for optical purposes from January 2012 to October 2014. The graft survival rates were constructed using the Kaplan-Meier method, and the effect of clinical and socioeconomic characteristics on time to graft failure were examined using Cox regression models. RESULTS: 118 patients met the inclusion criteria. The most common indication for surgery was keratoconus (66.1%), followed by corneal scar (22.0%). Despite all patients giving a verbal commitment to do so, 40 patients (33.9%) failed to make it to followup one year postoperatively. Graft survival at one year, inclusive of all indications, was 85.8%. Of the different indications, keratoconus had the highest one-year graft survival rate of 89.9%. Compared to the preoperative uncorrected visual acuity, 85.3% achieved an improvement at one year. Compared to patients who had completed college or university, the risk of developing graft failure was 4.7 times higher among patients with less education (P = 0.01). CONCLUSIONS: Corneal transplantation at Tenwek Hospital can be performed with a reasonable chance of success at one year, particularly in cases of keratoconus and in patients with higher educational backgrounds. Adherence to followup recommendations proves to be a challenge in this patient population. Additional studies of larger patient populations with longer follow up periods in similar settings may be helpful in informing appropriate patient selection and maximizing successful outcomes of corneal transplantation in low-resource settings.

Outcomes of Repeat Boston Type 1 Keratoprosthesis Implantation.

PURPOSE: To describe the outcomes and prognostic characteristics of patients who had a repeat Boston type 1 keratoprosthesis (KPro) implantation. DESIGN: Retrospective case series. METHODS: setting: Data regarding preoperative clinical and demographic characteristics and postoperative course during initial and repeat KPro placement were collected at multiple centers across the country. PATIENTS: Forty-eight eyes underwent explantation of KPro owing to complications between September 2003 and August 2014 at 5 participating tertiary eye care centers in the United States. Of those, 36 eyes that received a subsequent replacement device were included. MAIN OUTCOME MEASURES: Visual acuity (VA) outcomes and postoperative complications. RESULTS: Ocular surface disease was significantly more common in eyes that required a device explantation, compared to those that retained the device (P < .001). Sixty-seven percent of eyes (24/36) achieved VA ≥ 20/200 vision after the repeat KPro. The probability of these 24 eyes maintaining VA ≥ 20/200 after the repeat KPro was 87% at 1 year and 75% at 2 years. Predictors of the ability to maintain vision ≥ 20/200 following surgery were a better last-recorded vision before explantation (P = .0002) and better vision immediately after repeat KPro (P < .001). CONCLUSION: Ocular surface disease and its complications were associated with more frequent device removal. In these patients, repeat KPro resulted in restoration of vision. A reasonable visual acuity prior to device removal was associated with favorable long-term postoperative visual acuity and retention.

Outcomes After Descemet Stripping Automated Endothelial Keratoplasty in Patients With Glaucoma Drainage Devices.

PURPOSE: To evaluate outcomes after Descemet stripping automated endothelial keratoplasty in eyes with glaucoma drainage devices. METHODS: This is a retrospective review of 24 cases performed by a single surgeon (S.B.H.) on 20 eyes. Data were gathered on demographics, ocular history, surgical details, and postoperative outcomes. Outcome measures included primary graft failure, secondary graft failure, endothelial cell density (ECD), central corneal thickness (CCT), intraocular pressure, and visual acuity. RESULTS: With a mean follow-up of 30.3 ± 19.6 months, there was no occurrence of primary graft failure, and the rate of secondary graft failure was 29%. Survival rates at 1, 2, and 3 years, respectively, were 87% [95% confidence interval (CI): 65%-96%], 80% (95% CI: 55%-92%), and 70% (95% CI: 39%-88%). Compared with ECD of the donor lenticule, endothelial cell loss was 49 ± 16% (n = 21) at postoperative month 3, 59 ± 16% (n = 20) at month 6, 61 ± 20% (n = 16) at month 12, and stabilized at 75 ± 17% (n = 9) by month 18. Compared with CCT during the visit before surgery, CCT decreased to 83 ± 18% (n = 18) at postoperative month 3 and gradually increased to 95 ± 11% (n = 6) at month 24. There were 4 (17%) cases of intraocular pressure elevation above 25 mm Hg. Improved visual acuity occurred in 71% of patients. CONCLUSIONS: Descemet stripping automated endothelial keratoplasty in eyes with corneal edema secondary to endothelial dysfunction in the presence of a previous glaucoma drainage device is a successful procedure. However, intermediate term endothelial cell loss is significant, as is the graft failure rate.

Long-term outcomes of boston type 1 keratoprosthesis implantation: a retrospective multicenter cohort.

PURPOSE: To study the long-term outcomes of Boston type 1 keratoprosthesis (KPro) surgery. DESIGN: Retrospective, multicenter case series. PARTICIPANTS: A total of 158 eyes of 150 patients underwent KPro implantation at 5 participating tertiary centers in the United States between January 2003 and December 2006. Of those, 139 eyes of 133 patients were included in the analyses. METHODS: The medical records of consecutive adult patients who received KPro surgery were reviewed. All patients with at least 1 postoperative visit were retained in the outcomes analyses. In eyes in which a repeat KPro procedure was performed, only the outcomes of the initial surgery were analyzed. MAIN OUTCOME MEASURES: Visual acuity (VA) outcomes, postoperative complications, and device retention. RESULTS: The mean follow-up was 46.7 ± 26 months with all but 4 eyes having at least 6 months of follow-up. Preoperatively, only 10.8% of the eyes had VA of ≥ 20/200. Postoperatively, the VA in 70% of eyes improved to ≥ 20/200. The probability of maintaining VA of ≥ 20/200 at 7 years was 50%. The device retention rate was estimated at 67% at 7 years. The 7-year cumulative incidence of complications was 49.7% for retroprosthetic membrane formation, 21.6% for glaucoma surgery, 18.6% for retinal detachment, and 15.5% for endophthalmitis. CONCLUSIONS: Although the risk for complications with longer follow-up seemed to increase, this large multicenter cohort demonstrates favorable outcomes with KPro, with a large number of patients achieving and retaining useful vision over a 7-year period.

Descemet stripping endothelial keratoplasty for the treatment of combined fuchs corneal endothelial dystrophy and keratoconus.

PURPOSE: To report the first case series of patients with Fuchs corneal endothelial dystrophy (FCD) and keratoconus (KCN) who underwent Descemet stripping endothelial keratoplasty (DSEK). METHODS: This is a retrospective case series of 6 eyes of 4 patients with combined FCD and KCN who underwent DSEK at 3 different centers. Clinical information collected included corneal topography measurements, central corneal thickness, and endothelial cell count. Visual outcomes and change in keratometric measurements were evaluated. RESULTS: The follow-up for patients ranged from 10 to 72 months. The best-corrected visual acuity was 20/40 or better in all 6 eyes. The mean keratometric measurements decreased in all cases (range of 0.5-5.8 diopters); however, topography still demonstrated an inferior steepening in each case. CONCLUSIONS: Patients with FCD and KCN have been previously reported as being managed with penetrating keratoplasty. We present 6 eyes of 4 patients who were managed with DSEK for the FCD. Topographically, the characteristic inferior steepening of KCN did not change; however, all patients with DSEK had flatter postoperative keratometric measurements with improved visual acuity. If a DSEK is performed for FCD before apical corneal scarring from KCN, a good visual outcome may be achieved.

Endothelial morphometric measures to predict endothelial graft failure after penetrating keratoplasty.

IMPORTANCE: Endothelial morphometric measures have potential value in predicting graft failure after penetrating keratoplasty. OBJECTIVE: To determine whether preoperative and/or postoperative central morphometric measures (endothelial cell density [ECD], coefficient of variation [CV], and percentage of hexagonality [HEX]) and their postoperative changes are predictive of graft failure caused by endothelial decompensation after penetrating keratoplasty to treat a moderate-risk condition, principally Fuchs dystrophy or pseudophakic corneal edema. DESIGN: In a subset of Cornea Donor Study participants with graft failure, a central reading center determined preoperative and postoperative ECD, CV, and HEX from available central endothelial specular images. SETTING: Cornea Image Analysis Reading Center of the Specular Microscopy Ancillary Study. PARTICIPANTS: Eighteen patients with graft failure due to endothelial decompensation and 54 individuals matched for most donor and recipient measures at baseline whose grafts did not fail. MAIN OUTCOME MEASURE: Change in ECD, CV, and HEX values. RESULTS: Preoperative ECD was not associated with graft failure (P = .43); however, a lower ECD at 6 months was predictive of subsequent failure (P = .004). Coefficient of variation at 6 months was not associated with graft failure in univariate (P = .91) or multivariate (P = .79) analyses. We found a suggestive trend of higher graft failure with lower HEX values at 6 months (P = .02) but not at the established statistical significance (P < .01). The most recent CV or HEX values, as time-dependent variables, were not associated with graft failure (P = .26 and P = .81, respectively). Endothelial cell density values decreased during follow-up, whereas CV and HEX appear to fluctuate without an apparent trend. CONCLUSIONS AND RELEVANCE: Endothelial cell density at 6 months after penetrating keratoplasty is predictive of graft failure, whereas CV and HEX appear to fluctuate postoperatively, possibly indicating an unstable endothelial population in clear and failing grafts. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00006411.

Textural interface opacity after descemet stripping automated endothelial keratoplasty: a report of 30 cases and possible etiology.

PURPOSE: Descemet stripping automated endothelial keratoplasty (DSAEK) has its own set of complications including interface abnormalities. This case series presents the largest number of patients who developed textural interface opacity (TIO) at the graft-host interface after DSAEK. METHODS: This is a retrospective multicenter case series of 30 patients from 7 institutions with the finding of TIO. Clinical information collected included donor preparation details, recipient information, and surgical technique. Clinical outcomes included best-corrected visual acuity and status of TIO appearance at the last follow-up visit. Slit-lamp photographs were analyzed and compared. RESULTS: The majority of the patients (73%) had a best-corrected visual acuity of 20/40 or better. Four of the donor tissues were prepared with a microkeratome blade with the same lot number. Six patients had a central interface space between host and donor stromal surfaces--presumed interface fluid but potentially viscoelastic. A slight majority (57%) of patients had improvement in the severity of TIO, with 20% noted to have a complete resolution of TIO (mean follow-up of 11.9 months). Two clinical types of TIO were seen: an elongated type and a punctate type. CONCLUSIONS: Most patients with TIO after DSAEK obtain good visual outcomes. TIO spontaneously improves or even resolves during follow-up without intervention. The etiology of this condition is unknown, but we propose 2 different mechanisms. The elongated type could be secondary to an irregular cut of the donor with the microkeratome blade. The punctate type may be secondary to retained viscoelastic.

Retrospective review of graft dislocation rate associated with descemet stripping automated endothelial keratoplasty after primary failed penetrating keratoplasty.

PURPOSE: To report the rate of graft dislocation in patients who underwent Descemet stripping automated endothelial keratoplasty (DSAEK) after a previous penetrating keratoplasty (PKP). METHODS: Institutional review board-approved, multicenter, retrospective chart review. Inclusion criteria included: prior failed PKP and subsequent DSAEK. The primary outcomes measured in this study were the presence of a graft dislocation, rate of rebubble, and graft attachment. Additional variables included: presence of a prior glaucoma drainage device, graft-to-host size disparity, number of sutures remaining in PKP, and stripping of the Descemet membrane at the time of DSAEK surgery. RESULTS: Ninety patients (97 eyes) were included in the study. In 31% (30 of 97), the endothelial graft dislocated after surgery. All 30 cases required a rebubble except 1, which reattached spontaneously. Ninety-eight percent (95 of 97) of all grafts remained attached for the duration of the follow-up period. Only 2 eyes (2.2%) required repeat graft. Endothelial grafts dislocated in 67% of patients with glaucoma draining devices. The dislocation rate for grafts larger than the host was 12 of 49 (24%), equal to the host was 3 of 17 (18%), and smaller than the host was 8 of 19 (42%). Dislocations occurred in 5 of 21 (24%) of grafts with sutures remaining and 22 of 76 (29%) of those with all sutures out. Five of 12 (42%) cases of grafts performed without stripping the Descemet had dislocations. CONCLUSIONS: The graft dislocation rate in DSAEK procedures after PKP is comparable to that after primary DSAEK cases. Donor grafts that are smaller than the host PKP and the presence of prior glaucoma drainage devices are risk factors for higher rates of graft dislocation.

Late-onset deep infectious keratitis after descemet stripping endothelial keratoplasty with vent incisions.

PURPOSE: To report the clinical and histopathological findings of 3 cases of late-onset deep infectious keratitis after Descemet stripping endothelial keratoplasty (DSEK) with vent incisions. METHODS: From a retrospective review of 150 consecutive patients who underwent uncomplicated DSEK with vent incisions, 3 patients developed late-onset deep infectious keratitis. RESULTS: In case 1, the patient suffered a Pseudomonas corneal ulcer at the nasal vent incision after a dacryocystorhinostomy with stent, 16 months after DSEK. In case 2, a Streptococcus pneumoniae infection developed at the inferior vent incision from a spastic entropion 3 months after surgery. In case 3, an Enterococcus faecalis corneal ulcer presented as a deep stromal abscess in the nasal vent incision 7 weeks after DSEK. All cases required full-thickness penetrating keratoplasties. Visual acuities at the last follow-up were counting fingers (case 1), 20/80 (case 2), and 20/400 (case 3). CONCLUSIONS: Vent incisions in DSEK may allow bacterial keratitis to penetrate deeply leading to aggressive keratolysis. One must be cautious in using vent incisions in patients with increased bacterial flora and patients with poor ocular surface healing from systemic, local, or mechanical conditions. If vent incisions are performed, a midperipheral oblique incision, parallel to the limbus, with meticulous detail to wound construction is recommended.

Spontaneous reattachment of Descemet stripping automated endothelial keratoplasty lenticles: a case series of 12 patients.

PURPOSE: To review 12 cases of postoperative detachment and spontaneous reattachment of Descemet stripping automated endothelial keratoplasty (DSAEK) lenticles. DESIGN: Retrospective, observational case series. METHODS: This was a review of patients undergoing DSAEK at 7 institutions. Patients who had a significant detachment of their DSAEK lenticle during the postoperative period were identified and divided into 2 groups. Significant detachment was defined as either complete central interface fluid with bare peripheral attachment (group 1) or a free-floating lenticle in the anterior chamber (group 2). Patients who subsequently had a spontaneous reattachment of the lenticle were identified, with data regarding surgical technique and intraoperative and postoperative complications collected for analysis. RESULTS: Our cohort consisted of 12 eyes of 12 patients who met the definition of significant postoperative detachment with subsequent spontaneous reattachment. Four patients had complete central detachment with peripheral attachment (group 1), whereas 8 patients had a free-floating lenticle (group 2). Ten of the 12 patients had a successful outcome as defined as an attached and clear DSAEK lenticle. In our study, reattachment was seen as early as 5 days and as late as 7 months after surgery, with reattachment in 9 of 12 patients by day 25. CONCLUSIONS: Spontaneous reattachment of detached DSAEK lenticles may occur during the postoperative period. The decision of when to bring the patient back for a rebubble ultimately must be made on a case-by-case basis.

Descemetic DALK and predescemetic DALK: outcomes in 236 cases of keratoconus.

PURPOSE: To report the outcomes of our experience with deep anterior lamellar keratoplasty (DALK) in patients with keratoconus. METHODS: A retrospective evaluation of 236 eyes of 198 patients that have undergone DALK between 2000 and 2006 using the Tsubota, Sugita, Melles, or Anwar technique. We analyzed the frequency of true Descemet membrane exposure, which we termed dDALK, and the number of eyes in which a predescemetic plane was achieved, which we termed pdDALK. Pre- and postoperative visual acuity, endothelial cell count, and central corneal thickness were evaluated on 120 eyes followed in our department. RESULTS: A total of 139 of 236 (59%) eyes were classified as dDALK, with the Anwar technique showing the highest incidence of exposure of Descemet's membrane (127 of 164, 77%). Descemet ruptures occurred in 25 of 236 cases (10.5%). Three ruptures were converted to penetrating keratoplasty (PK). There was no difference in visual acuity between the pdDALK and dDALK groups at an average follow-up of 30.4 months, although the eyes in the dDALK group seemed to have faster visual recovery. Best spectacle corrected visual acuity postoperatively was at least 20/30 in 80-85% of eyes at the patient's last visit. Endothelial cell loss was 11-13%, with most of the loss occurring in the first 6 months. CONCLUSIONS: Performing DALK, we had the greatest likelihood of reaching Descemet's membrane with the Anwar Big Bubble technique. The visual outcomes are comparable to standard PK, avoiding the risk of endothelial rejection. Endothelial cell loss was low and the cell count was stable after 6 months.

No pathogenic mutations identified in the COL8A2 gene or four positional candidate genes in patients with posterior polymorphous corneal dystrophy.

PURPOSE: To identify the genetic basis of posterior polymorphous corneal dystrophy (PPCD) through screening of four positional candidate genes and the COL8A2 gene, in which a presumed pathogenic mutation has previously been identified in affected patients. METHODS: DNA extraction, PCR amplification, and direct sequencing of the COL8A2, BFSP1, CST3, MMP9, and SLPI genes were performed in 14 unrelated, affected patients and in unaffected family members. RESULTS: In the COL8A2 gene, the previously identified, presumed pathogenic mutation (Gln455Lys) was not discovered in any of the affected patients. A missense mutation, Thr502Met, was identified in 2 of the 14 affected probands, although it was not considered to be pathogenic, as it has been identified in unaffected individuals. Although several novel and previously identified single nucleotide polymorphisms producing synonymous and missense amino acid substitutions were identified in the COL8A2, BFSP1, CST3, MMP9, and SLPI genes, no presumed pathogenic sequence variants were found. CONCLUSIONS: No pathogenic mutations were identified in the COL8A2 gene or in several positional candidate genes in a series of patients with PPCD, indicating that other genetic factors are involved in the development of this autosomal dominant corneal dystrophy.

Characteristic clinical findings and visual outcomes.

PURPOSE: To describe a potentially serious complication of laser in situ keratomileusis (LASIK) that can masquerade as a persistent epithelial defect. SETTING: Refractive surgery centers in academic institutions. METHODS: Charts of 4 eyes in which epithelial-defect-masquerade syndrome was diagnosed were reviewed to determine the time to diagnosis and the presence of associated features that may have contributed to the delay in diagnosis. Clinical findings and outcomes of medical and surgical intervention were recorded. RESULTS: All eyes developed an epithelial defect involving the edge of the flap during surgery. The diagnosis of epithelial ingrowth was delayed because of the presence of stromal edema (n = 4), diffuse lamellar keratitis (n = 3), and contraction of the flap leading to gutter widening (n = 4). Epithelial ingrowth was diagnosed 5, 7, 15, and 60 days after LASIK. All eyes satisfied the following criteria: convexity of the peripheral epithelium at the edge of the flap associated with light reflections at the end of the flap, fluorescein pooling in the gutter, stromal edema, reduced best spectacle-corrected visual acuity (<20/60 in 3 eyes), and partial healing of the epithelial defect limited to the flap hinge. One eye developed stromal scarring and ulceration that required fortified antibiotics. Surgical repair included epithelial scraping after the flap was lifted and ironing followed by placement of a contact lens after surgery. The epithelial defect healed 5, 7, 21, and 24 days after surgery. The final uncorrected visual acuity ranged from 20/15 to 20/100. CONCLUSIONS: Epithelial ingrowth following LASIK-associated epithelial defects may masquerade as stromal edema associated with a persistent epithelial defect. A high index of suspicion for epithelial ingrowth is essential to avoid a delayed diagnosis, which can result in irreversible visual loss due to stromal melting and infectious keratitis.

Elevated intraocular pressure-induced interlamellar stromal keratitis.

PURPOSE: To describe a series of cases (Elevated Intraocular Pressure Induced Interlamellar Stromal Keratitis (PISK)) that appears to be identical to post-laser in situ keratomileusis (LASIK) diffuse lamellar keratitis (DLK), but was present at a later time frame and was associated with a significant elevation of intraocular pressure (IOP). Unlike DLK, this syndrome is not steroid responsive, but resolves with a lowering of the IOP. DESIGN: Retrospective, noncomparative, small case series. PARTICIPANTS: The medical records of four LASIK patients with IOP-induced interface changes for the 1-year period March 2000 to March 2001 were reviewed retrospectively. MAIN OUTCOME MEASURE: Slit-lamp appearance. RESULTS: In the four cases presented, the slit-lamp findings and visual degradation appeared identical to DLK. All cases, however, presented outside of the first postoperative week and were not associated with any antecedent trauma. All four cases failed to respond to high-dose topical steroids. Significant IOP elevations were noted in all cases, and the interface changes responded dramatically to both a lowering of the IOP and a discontinuation or lowering of the topical steroids. CONCLUSIONS: Elevated IOP-induced post-LASIK interface keratitis (PISK) is a poorly documented phenomena. Because the condition may be caused by or worsened by frequent topical steroids, early recognition is important. Treatment consists primarily of normalizing the IOP.